xref: /titanic_41/usr/src/uts/common/inet/udp/udp.c (revision 749f21d359d8fbd020c974a1a5227316221bfc9c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /* Copyright (c) 1990 Mentat Inc. */
27 
28 #pragma ident	"%Z%%M%	%I%	%E% SMI"
29 
30 const char udp_version[] = "%Z%%M%	%I%	%E% SMI";
31 
32 #include <sys/types.h>
33 #include <sys/stream.h>
34 #include <sys/dlpi.h>
35 #include <sys/pattr.h>
36 #include <sys/stropts.h>
37 #include <sys/strlog.h>
38 #include <sys/strsun.h>
39 #define	_SUN_TPI_VERSION 2
40 #include <sys/tihdr.h>
41 #include <sys/timod.h>
42 #include <sys/tiuser.h>
43 #include <sys/ddi.h>
44 #include <sys/sunddi.h>
45 #include <sys/strsubr.h>
46 #include <sys/suntpi.h>
47 #include <sys/xti_inet.h>
48 #include <sys/cmn_err.h>
49 #include <sys/kmem.h>
50 #include <sys/policy.h>
51 #include <sys/ucred.h>
52 #include <sys/zone.h>
53 
54 #include <sys/socket.h>
55 #include <sys/sockio.h>
56 #include <sys/vtrace.h>
57 #include <sys/debug.h>
58 #include <sys/isa_defs.h>
59 #include <sys/random.h>
60 #include <netinet/in.h>
61 #include <netinet/ip6.h>
62 #include <netinet/icmp6.h>
63 #include <netinet/udp.h>
64 #include <net/if.h>
65 #include <net/route.h>
66 
67 #include <inet/common.h>
68 #include <inet/ip.h>
69 #include <inet/ip_impl.h>
70 #include <inet/ip6.h>
71 #include <inet/ip_ire.h>
72 #include <inet/ip_if.h>
73 #include <inet/ip_multi.h>
74 #include <inet/mi.h>
75 #include <inet/mib2.h>
76 #include <inet/nd.h>
77 #include <inet/optcom.h>
78 #include <inet/snmpcom.h>
79 #include <inet/kstatcom.h>
80 #include <inet/udp_impl.h>
81 #include <inet/ipclassifier.h>
82 #include <inet/ipsec_impl.h>
83 #include <inet/ipp_common.h>
84 
85 /*
86  * The ipsec_info.h header file is here since it has the definition for the
87  * M_CTL message types used by IP to convey information to the ULP. The
88  * ipsec_info.h needs the pfkeyv2.h, hence the latters presence.
89  */
90 #include <net/pfkeyv2.h>
91 #include <inet/ipsec_info.h>
92 
93 /*
94  * Synchronization notes:
95  *
96  * UDP uses a combination of its internal perimeter, a global lock and
97  * a set of bind hash locks to protect its data structures.  Please see
98  * the note above udp_mode_assertions for details about the internal
99  * perimeter.
100  *
101  * When a UDP endpoint is bound to a local port, it is inserted into
102  * a bind hash list.  The list consists of an array of udp_fanout_t buckets.
103  * The size of the array is controlled by the udp_bind_fanout_size variable.
104  * This variable can be changed in /etc/system if the default value is
105  * not large enough.  Each bind hash bucket is protected by a per bucket
106  * lock.  It protects the udp_bind_hash and udp_ptpbhn fields in the udp_t
107  * structure.  An UDP endpoint is removed from the bind hash list only
108  * when it is being unbound or being closed.  The per bucket lock also
109  * protects a UDP endpoint's state changes.
110  *
111  * Plumbing notes:
112  *
113  * Both udp and ip are merged, but the streams plumbing is kept unchanged
114  * in that udp is always pushed atop /dev/ip.  This is done to preserve
115  * backwards compatibility for certain applications which rely on such
116  * plumbing geometry to do things such as issuing I_POP on the stream
117  * in order to obtain direct access to /dev/ip, etc.
118  *
119  * All UDP processings happen in the /dev/ip instance; the udp module
120  * instance does not possess any state about the endpoint, and merely
121  * acts as a dummy module whose presence is to keep the streams plumbing
122  * appearance unchanged.  At open time /dev/ip allocates a conn_t that
123  * happens to embed a udp_t.  This stays dormant until the time udp is
124  * pushed, which indicates to /dev/ip that it must convert itself from
125  * an IP to a UDP endpoint.
126  *
127  * We only allow for the following plumbing cases:
128  *
129  * Normal:
130  *	/dev/ip is first opened and later udp is pushed directly on top.
131  *	This is the default action that happens when a udp socket or
132  *	/dev/udp is opened.  The conn_t created by /dev/ip instance is
133  *	now shared and is marked with IPCL_UDP.
134  *
135  * SNMP-only:
136  *	udp is pushed on top of a module other than /dev/ip.  When this
137  *	happens it will support only SNMP semantics.  A new conn_t is
138  *	allocated and marked with IPCL_UDPMOD.
139  *
140  * The above cases imply that we don't support any intermediate module to
141  * reside in between /dev/ip and udp -- in fact, we never supported such
142  * scenario in the past as the inter-layer communication semantics have
143  * always been private.  Also note that the normal case allows for SNMP
144  * requests to be processed in addition to the rest of UDP operations.
145  *
146  * The normal case plumbing is depicted by the following diagram:
147  *
148  *	+---------------+---------------+
149  *	|		|		| udp
150  *	|     udp_wq	|    udp_rq	|
151  *	|		|    UDP_RD	|
152  *	|		|		|
153  *	+---------------+---------------+
154  *		|		^
155  *		v		|
156  *	+---------------+---------------+
157  *	|		|		| /dev/ip
158  *	|     ip_wq	|     ip_rq	| conn_t
159  *	|     UDP_WR	|		|
160  *	|		|		|
161  *	+---------------+---------------+
162  *
163  * Messages arriving at udp_wq from above will end up in ip_wq before
164  * it gets processed, i.e. udp write entry points will advance udp_wq
165  * and use its q_next value as ip_wq in order to use the conn_t that
166  * is stored in its q_ptr.  Likewise, messages generated by ip to the
167  * module above udp will appear as if they are originated from udp_rq,
168  * i.e. putnext() calls to the module above udp is done using the
169  * udp_rq instead of ip_rq in order to avoid udp_rput() which does
170  * nothing more than calling putnext().
171  *
172  * The above implies the following rule of thumb:
173  *
174  *   1. udp_t is obtained from conn_t, which is created by the /dev/ip
175  *	instance and is stored in q_ptr of both ip_wq and ip_rq.  There
176  *	is no direct reference to conn_t from either udp_wq or udp_rq.
177  *
178  *   2. Write-side entry points of udp can obtain the conn_t via the
179  *	Q_TO_CONN() macro, using the queue value obtain from UDP_WR().
180  *
181  *   3. While in /dev/ip context, putnext() to the module above udp can
182  *	be done by supplying the queue value obtained from UDP_RD().
183  *
184  */
185 
186 static queue_t *UDP_WR(queue_t *);
187 static queue_t *UDP_RD(queue_t *);
188 
189 udp_stat_t udp_statistics = {
190 	{ "udp_ip_send",		KSTAT_DATA_UINT64 },
191 	{ "udp_ip_ire_send",		KSTAT_DATA_UINT64 },
192 	{ "udp_ire_null",		KSTAT_DATA_UINT64 },
193 	{ "udp_drain",			KSTAT_DATA_UINT64 },
194 	{ "udp_sock_fallback",		KSTAT_DATA_UINT64 },
195 	{ "udp_rrw_busy",		KSTAT_DATA_UINT64 },
196 	{ "udp_rrw_msgcnt",		KSTAT_DATA_UINT64 },
197 	{ "udp_out_sw_cksum",		KSTAT_DATA_UINT64 },
198 	{ "udp_out_sw_cksum_bytes",	KSTAT_DATA_UINT64 },
199 	{ "udp_out_opt",		KSTAT_DATA_UINT64 },
200 	{ "udp_out_err_notconn",	KSTAT_DATA_UINT64 },
201 	{ "udp_out_err_output",		KSTAT_DATA_UINT64 },
202 	{ "udp_out_err_tudr",		KSTAT_DATA_UINT64 },
203 	{ "udp_in_pktinfo",		KSTAT_DATA_UINT64 },
204 	{ "udp_in_recvdstaddr",		KSTAT_DATA_UINT64 },
205 	{ "udp_in_recvopts",		KSTAT_DATA_UINT64 },
206 	{ "udp_in_recvif",		KSTAT_DATA_UINT64 },
207 	{ "udp_in_recvslla",		KSTAT_DATA_UINT64 },
208 	{ "udp_in_recvucred",		KSTAT_DATA_UINT64 },
209 	{ "udp_in_recvttl",		KSTAT_DATA_UINT64 },
210 	{ "udp_in_recvhopopts",		KSTAT_DATA_UINT64 },
211 	{ "udp_in_recvhoplimit",	KSTAT_DATA_UINT64 },
212 	{ "udp_in_recvdstopts",		KSTAT_DATA_UINT64 },
213 	{ "udp_in_recvrtdstopts",	KSTAT_DATA_UINT64 },
214 	{ "udp_in_recvrthdr",		KSTAT_DATA_UINT64 },
215 	{ "udp_in_recvpktinfo",		KSTAT_DATA_UINT64 },
216 	{ "udp_in_recvtclass",		KSTAT_DATA_UINT64 },
217 #ifdef DEBUG
218 	{ "udp_data_conn",		KSTAT_DATA_UINT64 },
219 	{ "udp_data_notconn",		KSTAT_DATA_UINT64 },
220 #endif
221 };
222 
223 static kstat_t *udp_ksp;
224 struct kmem_cache *udp_cache;
225 
226 /*
227  * Bind hash list size and hash function.  It has to be a power of 2 for
228  * hashing.
229  */
230 #define	UDP_BIND_FANOUT_SIZE	512
231 #define	UDP_BIND_HASH(lport) \
232 	((ntohs((uint16_t)lport)) & (udp_bind_fanout_size - 1))
233 
234 /* UDP bind fanout hash structure. */
235 typedef struct udp_fanout_s {
236 	udp_t *uf_udp;
237 	kmutex_t uf_lock;
238 #if defined(_LP64) || defined(_I32LPx)
239 	char	uf_pad[48];
240 #else
241 	char	uf_pad[56];
242 #endif
243 } udp_fanout_t;
244 
245 uint_t udp_bind_fanout_size = UDP_BIND_FANOUT_SIZE;
246 /* udp_fanout_t *udp_bind_fanout. */
247 static udp_fanout_t *udp_bind_fanout;
248 
249 /*
250  * This controls the rate some ndd info report functions can be used
251  * by non-priviledged users.  It stores the last time such info is
252  * requested.  When those report functions are called again, this
253  * is checked with the current time and compare with the ndd param
254  * udp_ndd_get_info_interval.
255  */
256 static clock_t udp_last_ndd_get_info_time;
257 #define	NDD_TOO_QUICK_MSG \
258 	"ndd get info rate too high for non-priviledged users, try again " \
259 	"later.\n"
260 #define	NDD_OUT_OF_BUF_MSG	"<< Out of buffer >>\n"
261 
262 static void	udp_addr_req(queue_t *q, mblk_t *mp);
263 static void	udp_bind(queue_t *q, mblk_t *mp);
264 static void	udp_bind_hash_insert(udp_fanout_t *uf, udp_t *udp);
265 static void	udp_bind_hash_remove(udp_t *udp, boolean_t caller_holds_lock);
266 static int	udp_build_hdrs(queue_t *q, udp_t *udp);
267 static void	udp_capability_req(queue_t *q, mblk_t *mp);
268 static int	udp_close(queue_t *q);
269 static void	udp_connect(queue_t *q, mblk_t *mp);
270 static void	udp_disconnect(queue_t *q, mblk_t *mp);
271 static void	udp_err_ack(queue_t *q, mblk_t *mp, t_scalar_t t_error,
272 		    int sys_error);
273 static void	udp_err_ack_prim(queue_t *q, mblk_t *mp, int primitive,
274 		    t_scalar_t tlierr, int unixerr);
275 static int	udp_extra_priv_ports_get(queue_t *q, mblk_t *mp, caddr_t cp,
276 		    cred_t *cr);
277 static int	udp_extra_priv_ports_add(queue_t *q, mblk_t *mp,
278 		    char *value, caddr_t cp, cred_t *cr);
279 static int	udp_extra_priv_ports_del(queue_t *q, mblk_t *mp,
280 		    char *value, caddr_t cp, cred_t *cr);
281 static void	udp_icmp_error(queue_t *q, mblk_t *mp);
282 static void	udp_icmp_error_ipv6(queue_t *q, mblk_t *mp);
283 static void	udp_info_req(queue_t *q, mblk_t *mp);
284 static mblk_t	*udp_ip_bind_mp(udp_t *udp, t_scalar_t bind_prim,
285 		    t_scalar_t addr_length);
286 static int	udp_open(queue_t *q, dev_t *devp, int flag, int sflag,
287 		    cred_t *credp);
288 static  int	udp_unitdata_opt_process(queue_t *q, mblk_t *mp,
289 		    int *errorp, void *thisdg_attrs);
290 static boolean_t udp_opt_allow_udr_set(t_scalar_t level, t_scalar_t name);
291 static int	udp_param_get(queue_t *q, mblk_t *mp, caddr_t cp, cred_t *cr);
292 static boolean_t udp_param_register(udpparam_t *udppa, int cnt);
293 static int	udp_param_set(queue_t *q, mblk_t *mp, char *value, caddr_t cp,
294 		    cred_t *cr);
295 static int	udp_pkt_set(uchar_t *invalp, uint_t inlen, boolean_t sticky,
296 		    uchar_t **optbufp, uint_t *optlenp);
297 static void	udp_report_item(mblk_t *mp, udp_t *udp);
298 static void	udp_rput(queue_t *q, mblk_t *mp);
299 static void	udp_rput_other(queue_t *, mblk_t *);
300 static int	udp_rinfop(queue_t *q, infod_t *dp);
301 static int	udp_rrw(queue_t *q, struiod_t *dp);
302 static	void	udp_rput_bind_ack(queue_t *q, mblk_t *mp);
303 static int	udp_status_report(queue_t *q, mblk_t *mp, caddr_t cp,
304 		    cred_t *cr);
305 static void	udp_send_data(udp_t *udp, queue_t *q, mblk_t *mp, ipha_t *ipha);
306 static void	udp_ud_err(queue_t *q, mblk_t *mp, uchar_t *destaddr,
307 		    t_scalar_t destlen, t_scalar_t err);
308 static void	udp_unbind(queue_t *q, mblk_t *mp);
309 static in_port_t udp_update_next_port(in_port_t port, boolean_t random);
310 static void	udp_wput(queue_t *q, mblk_t *mp);
311 static mblk_t	*udp_output_v4(conn_t *, mblk_t *mp, ipaddr_t v4dst,
312 		    uint16_t port, uint_t srcid, int *error);
313 static mblk_t	*udp_output_v6(conn_t *connp, mblk_t *mp, sin6_t *sin6,
314 		    t_scalar_t tudr_optlen, int *error);
315 static void	udp_wput_other(queue_t *q, mblk_t *mp);
316 static void	udp_wput_iocdata(queue_t *q, mblk_t *mp);
317 static void	udp_output(conn_t *connp, mblk_t *mp, struct sockaddr *addr,
318 		    socklen_t addrlen);
319 static size_t	udp_set_rcv_hiwat(udp_t *udp, size_t size);
320 
321 static void	udp_kstat_init(void);
322 static void	udp_kstat_fini(void);
323 static int	udp_kstat_update(kstat_t *kp, int rw);
324 static void	udp_input_wrapper(void *arg, mblk_t *mp, void *arg2);
325 static void	udp_rput_other_wrapper(void *arg, mblk_t *mp, void *arg2);
326 static void	udp_wput_other_wrapper(void *arg, mblk_t *mp, void *arg2);
327 static void	udp_resume_bind_cb(void *arg, mblk_t *mp, void *arg2);
328 
329 static void	udp_rcv_enqueue(queue_t *q, udp_t *udp, mblk_t *mp,
330 		    uint_t pkt_len);
331 static void	udp_rcv_drain(queue_t *q, udp_t *udp, boolean_t closing);
332 static void	udp_enter(conn_t *, mblk_t *, sqproc_t, uint8_t);
333 static void	udp_exit(conn_t *);
334 static void	udp_become_writer(conn_t *, mblk_t *, sqproc_t, uint8_t);
335 #ifdef DEBUG
336 static void	udp_mode_assertions(udp_t *, int);
337 #endif /* DEBUG */
338 
339 major_t UDP6_MAJ;
340 #define	UDP6 "udp6"
341 
342 #define	UDP_RECV_HIWATER	(56 * 1024)
343 #define	UDP_RECV_LOWATER	128
344 #define	UDP_XMIT_HIWATER	(56 * 1024)
345 #define	UDP_XMIT_LOWATER	1024
346 
347 static struct module_info udp_info =  {
348 	UDP_MOD_ID, UDP_MOD_NAME, 1, INFPSZ, UDP_RECV_HIWATER, UDP_RECV_LOWATER
349 };
350 
351 static struct qinit udp_rinit = {
352 	(pfi_t)udp_rput, NULL, udp_open, udp_close, NULL,
353 	&udp_info, NULL, udp_rrw, udp_rinfop, STRUIOT_STANDARD
354 };
355 
356 static struct qinit udp_winit = {
357 	(pfi_t)udp_wput, NULL, NULL, NULL, NULL,
358 	&udp_info, NULL, NULL, NULL, STRUIOT_NONE
359 };
360 
361 static struct qinit winit = {
362 	(pfi_t)putnext, NULL, NULL, NULL, NULL,
363 	&udp_info, NULL, NULL, NULL, STRUIOT_NONE
364 };
365 
366 /* Support for just SNMP if UDP is not pushed directly over device IP */
367 struct qinit udp_snmp_rinit = {
368 	(pfi_t)putnext, NULL, udp_open, ip_snmpmod_close, NULL,
369 	&udp_info, NULL, NULL, NULL, STRUIOT_NONE
370 };
371 
372 struct qinit udp_snmp_winit = {
373 	(pfi_t)ip_snmpmod_wput, NULL, udp_open, ip_snmpmod_close, NULL,
374 	&udp_info, NULL, NULL, NULL, STRUIOT_NONE
375 };
376 
377 struct streamtab udpinfo = {
378 	&udp_rinit, &winit
379 };
380 
381 static	sin_t	sin_null;	/* Zero address for quick clears */
382 static	sin6_t	sin6_null;	/* Zero address for quick clears */
383 
384 /* Hint not protected by any lock */
385 static in_port_t	udp_g_next_port_to_try;
386 
387 /*
388  * Extra privileged ports. In host byte order.
389  */
390 #define	UDP_NUM_EPRIV_PORTS	64
391 static int	udp_g_num_epriv_ports = UDP_NUM_EPRIV_PORTS;
392 static in_port_t udp_g_epriv_ports[UDP_NUM_EPRIV_PORTS] = { 2049, 4045 };
393 
394 /* Only modified during _init and _fini thus no locking is needed. */
395 static IDP	udp_g_nd;	/* Points to table of UDP ND variables. */
396 
397 /* MIB-2 stuff for SNMP */
398 static mib2_udp_t	udp_mib;	/* SNMP fixed size info */
399 static kstat_t		*udp_mibkp;	/* kstat exporting udp_mib data */
400 
401 #define	UDP_MAXPACKET_IPV4 (IP_MAXPACKET - UDPH_SIZE - IP_SIMPLE_HDR_LENGTH)
402 
403 /* Default structure copied into T_INFO_ACK messages */
404 static struct T_info_ack udp_g_t_info_ack_ipv4 = {
405 	T_INFO_ACK,
406 	UDP_MAXPACKET_IPV4,	/* TSDU_size. Excl. headers */
407 	T_INVALID,	/* ETSU_size.  udp does not support expedited data. */
408 	T_INVALID,	/* CDATA_size. udp does not support connect data. */
409 	T_INVALID,	/* DDATA_size. udp does not support disconnect data. */
410 	sizeof (sin_t),	/* ADDR_size. */
411 	0,		/* OPT_size - not initialized here */
412 	UDP_MAXPACKET_IPV4,	/* TIDU_size.  Excl. headers */
413 	T_CLTS,		/* SERV_type.  udp supports connection-less. */
414 	TS_UNBND,	/* CURRENT_state.  This is set from udp_state. */
415 	(XPG4_1|SENDZERO) /* PROVIDER_flag */
416 };
417 
418 #define	UDP_MAXPACKET_IPV6 (IP_MAXPACKET - UDPH_SIZE - IPV6_HDR_LEN)
419 
420 static	struct T_info_ack udp_g_t_info_ack_ipv6 = {
421 	T_INFO_ACK,
422 	UDP_MAXPACKET_IPV6,	/* TSDU_size.  Excl. headers */
423 	T_INVALID,	/* ETSU_size.  udp does not support expedited data. */
424 	T_INVALID,	/* CDATA_size. udp does not support connect data. */
425 	T_INVALID,	/* DDATA_size. udp does not support disconnect data. */
426 	sizeof (sin6_t), /* ADDR_size. */
427 	0,		/* OPT_size - not initialized here */
428 	UDP_MAXPACKET_IPV6,	/* TIDU_size. Excl. headers */
429 	T_CLTS,		/* SERV_type.  udp supports connection-less. */
430 	TS_UNBND,	/* CURRENT_state.  This is set from udp_state. */
431 	(XPG4_1|SENDZERO) /* PROVIDER_flag */
432 };
433 
434 /* largest UDP port number */
435 #define	UDP_MAX_PORT	65535
436 
437 /*
438  * Table of ND variables supported by udp.  These are loaded into udp_g_nd
439  * in udp_open.
440  * All of these are alterable, within the min/max values given, at run time.
441  */
442 /* BEGIN CSTYLED */
443 udpparam_t udp_param_arr[] = {
444  /*min		max		value		name */
445  { 0L,		256,		32,		"udp_wroff_extra" },
446  { 1L,		255,		255,		"udp_ipv4_ttl" },
447  { 0,		IPV6_MAX_HOPS,	IPV6_DEFAULT_HOPS, "udp_ipv6_hoplimit"},
448  { 1024,	(32 * 1024),	1024,		"udp_smallest_nonpriv_port" },
449  { 0,		1,		1,		"udp_do_checksum" },
450  { 1024,	UDP_MAX_PORT,	(32 * 1024),	"udp_smallest_anon_port" },
451  { 1024,	UDP_MAX_PORT,	UDP_MAX_PORT,	"udp_largest_anon_port" },
452  { UDP_XMIT_LOWATER, (1<<30), UDP_XMIT_HIWATER,	"udp_xmit_hiwat"},
453  { 0,		     (1<<30), UDP_XMIT_LOWATER, "udp_xmit_lowat"},
454  { UDP_RECV_LOWATER, (1<<30), UDP_RECV_HIWATER,	"udp_recv_hiwat"},
455  { 65536,	(1<<30),	2*1024*1024,	"udp_max_buf"},
456  { 100,		60000,		1000,		"udp_ndd_get_info_interval"},
457 };
458 /* END CSTYLED */
459 
460 /*
461  * The smallest anonymous port in the priviledged port range which UDP
462  * looks for free port.  Use in the option UDP_ANONPRIVBIND.
463  */
464 static in_port_t udp_min_anonpriv_port = 512;
465 
466 /* If set to 0, pick ephemeral port sequentially; otherwise randomly. */
467 uint32_t udp_random_anon_port = 1;
468 
469 /*
470  * Hook functions to enable cluster networking.
471  * On non-clustered systems these vectors must always be NULL
472  */
473 
474 void (*cl_inet_bind)(uchar_t protocol, sa_family_t addr_family,
475     uint8_t *laddrp, in_port_t lport) = NULL;
476 void (*cl_inet_unbind)(uint8_t protocol, sa_family_t addr_family,
477     uint8_t *laddrp, in_port_t lport) = NULL;
478 
479 typedef union T_primitives *t_primp_t;
480 
481 #define	UDP_ENQUEUE_MP(udp, mp, proc, tag) {			\
482 	ASSERT((mp)->b_prev == NULL && (mp)->b_queue == NULL);	\
483 	ASSERT(MUTEX_HELD(&(udp)->udp_connp->conn_lock));	\
484 	(mp)->b_queue = (queue_t *)((uintptr_t)tag);		\
485 	(mp)->b_prev = (mblk_t *)proc;				\
486 	if ((udp)->udp_mphead == NULL)				\
487 		(udp)->udp_mphead = (mp);			\
488 	else							\
489 		(udp)->udp_mptail->b_next = (mp);		\
490 	(udp)->udp_mptail = (mp);				\
491 	(udp)->udp_mpcount++;					\
492 }
493 
494 #define	UDP_READERS_INCREF(udp) {				\
495 	ASSERT(MUTEX_HELD(&(udp)->udp_connp->conn_lock));	\
496 	(udp)->udp_reader_count++;				\
497 }
498 
499 #define	UDP_READERS_DECREF(udp) {				\
500 	ASSERT(MUTEX_HELD(&(udp)->udp_connp->conn_lock));	\
501 	(udp)->udp_reader_count--;				\
502 	if ((udp)->udp_reader_count == 0)			\
503 		cv_broadcast(&(udp)->udp_connp->conn_cv);	\
504 }
505 
506 #define	UDP_SQUEUE_DECREF(udp) {				\
507 	ASSERT(MUTEX_HELD(&(udp)->udp_connp->conn_lock));	\
508 	(udp)->udp_squeue_count--;				\
509 	if ((udp)->udp_squeue_count == 0)			\
510 		cv_broadcast(&(udp)->udp_connp->conn_cv);	\
511 }
512 
513 /*
514  * Notes on UDP endpoint synchronization:
515  *
516  * UDP needs exclusive operation on a per endpoint basis, when executing
517  * functions that modify the endpoint state.  udp_rput_other() deals with
518  * packets with IP options, and processing these packets end up having
519  * to update the endpoint's option related state.  udp_wput_other() deals
520  * with control operations from the top, e.g. connect() that needs to
521  * update the endpoint state.  These could be synchronized using locks,
522  * but the current version uses squeues for this purpose.  squeues may
523  * give performance improvement for certain cases such as connected UDP
524  * sockets; thus the framework allows for using squeues.
525  *
526  * The perimeter routines are described as follows:
527  *
528  * udp_enter():
529  *	Enter the UDP endpoint perimeter.
530  *
531  * udp_become_writer():
532  *	Become exclusive on the UDP endpoint.  Specifies a function
533  *	that will be called exclusively either immediately or later
534  *	when the perimeter is available exclusively.
535  *
536  * udp_exit():
537  *	Exit the UDP perimeter.
538  *
539  * Entering UDP from the top or from the bottom must be done using
540  * udp_enter().  No lock must be held while attempting to enter the UDP
541  * perimeter.  When finished, udp_exit() must be called to get out of
542  * the perimeter.
543  *
544  * UDP operates in either MT_HOT mode or in SQUEUE mode.  In MT_HOT mode,
545  * multiple threads may enter a UDP endpoint concurrently.  This is used
546  * for sending and/or receiving normal data.  Control operations and other
547  * special cases call udp_become_writer() to become exclusive on a per
548  * endpoint basis and this results in transitioning to SQUEUE mode.  squeue
549  * by definition serializes access to the conn_t.  When there are no more
550  * pending messages on the squeue for the UDP connection, the endpoint
551  * reverts to MT_HOT mode.  During the interregnum when not all MT threads
552  * of an endpoint have finished, messages are queued in the UDP endpoint
553  * and the UDP is in UDP_MT_QUEUED mode or UDP_QUEUED_SQUEUE mode.
554  *
555  * These modes have the following analogs:
556  *
557  *	UDP_MT_HOT/udp_reader_count==0		none
558  *	UDP_MT_HOT/udp_reader_count>0		RW_READ_LOCK
559  *	UDP_MT_QUEUED				RW_WRITE_WANTED
560  *	UDP_SQUEUE or UDP_QUEUED_SQUEUE		RW_WRITE_LOCKED
561  *
562  * Stable modes:	UDP_MT_HOT, UDP_SQUEUE
563  * Transient modes:	UDP_MT_QUEUED, UDP_QUEUED_SQUEUE
564  *
565  * While in stable modes, UDP keeps track of the number of threads
566  * operating on the endpoint.  The udp_reader_count variable represents
567  * the number of threads entering the endpoint as readers while it is
568  * in UDP_MT_HOT mode.  Transitioning to UDP_SQUEUE happens when there
569  * is only a single reader, i.e. when this counter drops to 1.  Likewise,
570  * udp_squeue_count represents the number of threads operating on the
571  * endpoint's squeue while it is in UDP_SQUEUE mode.  The mode transition
572  * to UDP_MT_HOT happens after the last thread exits the endpoint, i.e.
573  * when this counter drops to 0.
574  *
575  * The default mode is set to UDP_MT_HOT and UDP alternates between
576  * UDP_MT_HOT and UDP_SQUEUE as shown in the state transition below.
577  *
578  * Mode transition:
579  * ----------------------------------------------------------------
580  * old mode		Event				New mode
581  * ----------------------------------------------------------------
582  * UDP_MT_HOT		Call to udp_become_writer()	UDP_SQUEUE
583  *			and udp_reader_count == 1
584  *
585  * UDP_MT_HOT		Call to udp_become_writer()	UDP_MT_QUEUED
586  *			and udp_reader_count > 1
587  *
588  * UDP_MT_QUEUED	udp_reader_count drops to zero	UDP_QUEUED_SQUEUE
589  *
590  * UDP_QUEUED_SQUEUE	All messages enqueued on the	UDP_SQUEUE
591  *			internal UDP queue successfully
592  *			moved to squeue AND udp_squeue_count != 0
593  *
594  * UDP_QUEUED_SQUEUE	All messages enqueued on the	UDP_MT_HOT
595  *			internal UDP queue successfully
596  *			moved to squeue AND udp_squeue_count
597  *			drops to zero
598  *
599  * UDP_SQUEUE		udp_squeue_count drops to zero	UDP_MT_HOT
600  * ----------------------------------------------------------------
601  */
602 
603 static queue_t *
604 UDP_WR(queue_t *q)
605 {
606 	ASSERT(q->q_ptr == NULL && _OTHERQ(q)->q_ptr == NULL);
607 	ASSERT(WR(q)->q_next != NULL && WR(q)->q_next->q_ptr != NULL);
608 	ASSERT(IPCL_IS_UDP(Q_TO_CONN(WR(q)->q_next)));
609 
610 	return (_WR(q)->q_next);
611 }
612 
613 static queue_t *
614 UDP_RD(queue_t *q)
615 {
616 	ASSERT(q->q_ptr != NULL && _OTHERQ(q)->q_ptr != NULL);
617 	ASSERT(IPCL_IS_UDP(Q_TO_CONN(q)));
618 	ASSERT(RD(q)->q_next != NULL && RD(q)->q_next->q_ptr == NULL);
619 
620 	return (_RD(q)->q_next);
621 }
622 
623 #ifdef DEBUG
624 #define	UDP_MODE_ASSERTIONS(udp, caller) udp_mode_assertions(udp, caller)
625 #else
626 #define	UDP_MODE_ASSERTIONS(udp, caller)
627 #endif
628 
629 /* Invariants */
630 #ifdef DEBUG
631 
632 uint32_t udp_count[4];
633 
634 /* Context of udp_mode_assertions */
635 #define	UDP_ENTER		1
636 #define	UDP_BECOME_WRITER	2
637 #define	UDP_EXIT		3
638 
639 static void
640 udp_mode_assertions(udp_t *udp, int caller)
641 {
642 	ASSERT(MUTEX_HELD(&udp->udp_connp->conn_lock));
643 
644 	switch (udp->udp_mode) {
645 	case UDP_MT_HOT:
646 		/*
647 		 * Messages have not yet been enqueued on the internal queue,
648 		 * otherwise we would have switched to UDP_MT_QUEUED. Likewise
649 		 * by definition, there can't be any messages enqueued on the
650 		 * squeue. The UDP could be quiescent, so udp_reader_count
651 		 * could be zero at entry.
652 		 */
653 		ASSERT(udp->udp_mphead == NULL && udp->udp_mpcount == 0 &&
654 		    udp->udp_squeue_count == 0);
655 		ASSERT(caller == UDP_ENTER || udp->udp_reader_count != 0);
656 		udp_count[0]++;
657 		break;
658 
659 	case UDP_MT_QUEUED:
660 		/*
661 		 * The last MT thread to exit the udp perimeter empties the
662 		 * internal queue and then switches the UDP to
663 		 * UDP_QUEUED_SQUEUE mode. Since we are still in UDP_MT_QUEUED
664 		 * mode, it means there must be at least 1 MT thread still in
665 		 * the perimeter and at least 1 message on the internal queue.
666 		 */
667 		ASSERT(udp->udp_reader_count >= 1 && udp->udp_mphead != NULL &&
668 		    udp->udp_mpcount != 0 && udp->udp_squeue_count == 0);
669 		udp_count[1]++;
670 		break;
671 
672 	case UDP_QUEUED_SQUEUE:
673 		/*
674 		 * The switch has happened from MT to SQUEUE. So there can't
675 		 * any MT threads. Messages could still pile up on the internal
676 		 * queue until the transition is complete and we move to
677 		 * UDP_SQUEUE mode. We can't assert on nonzero udp_squeue_count
678 		 * since the squeue could drain any time.
679 		 */
680 		ASSERT(udp->udp_reader_count == 0);
681 		udp_count[2]++;
682 		break;
683 
684 	case UDP_SQUEUE:
685 		/*
686 		 * The transition is complete. Thre can't be any messages on
687 		 * the internal queue. The udp could be quiescent or the squeue
688 		 * could drain any time, so we can't assert on nonzero
689 		 * udp_squeue_count during entry. Nor can we assert that
690 		 * udp_reader_count is zero, since, a reader thread could have
691 		 * directly become writer in line by calling udp_become_writer
692 		 * without going through the queued states.
693 		 */
694 		ASSERT(udp->udp_mphead == NULL && udp->udp_mpcount == 0);
695 		ASSERT(caller == UDP_ENTER || udp->udp_squeue_count != 0);
696 		udp_count[3]++;
697 		break;
698 	}
699 }
700 #endif
701 
702 #define	_UDP_ENTER(connp, mp, proc, tag) {				\
703 	udp_t *_udp = (connp)->conn_udp;				\
704 									\
705 	mutex_enter(&(connp)->conn_lock);				\
706 	if ((connp)->conn_state_flags & CONN_CLOSING) {			\
707 		mutex_exit(&(connp)->conn_lock);			\
708 		freemsg(mp);						\
709 	} else {							\
710 		UDP_MODE_ASSERTIONS(_udp, UDP_ENTER);			\
711 									\
712 		switch (_udp->udp_mode) {				\
713 		case UDP_MT_HOT:					\
714 			/* We can execute as reader right away. */	\
715 			UDP_READERS_INCREF(_udp);			\
716 			mutex_exit(&(connp)->conn_lock);		\
717 			(*(proc))(connp, mp, (connp)->conn_sqp);	\
718 			break;						\
719 									\
720 		case UDP_SQUEUE:					\
721 			/*						\
722 			 * We are in squeue mode, send the		\
723 			 * packet to the squeue				\
724 			 */						\
725 			_udp->udp_squeue_count++;			\
726 			CONN_INC_REF_LOCKED(connp);			\
727 			mutex_exit(&(connp)->conn_lock);		\
728 			squeue_enter((connp)->conn_sqp, mp, proc,	\
729 			    connp, tag);				\
730 			break;						\
731 									\
732 		case UDP_MT_QUEUED:					\
733 		case UDP_QUEUED_SQUEUE:					\
734 			/*						\
735 			 * Some messages may have been enqueued		\
736 			 * ahead of us.  Enqueue the new message	\
737 			 * at the tail of the internal queue to		\
738 			 * preserve message ordering.			\
739 			 */						\
740 			UDP_ENQUEUE_MP(_udp, mp, proc, tag);		\
741 			mutex_exit(&(connp)->conn_lock);		\
742 			break;						\
743 		}							\
744 	}								\
745 }
746 
747 static void
748 udp_enter(conn_t *connp, mblk_t *mp, sqproc_t proc, uint8_t tag)
749 {
750 	_UDP_ENTER(connp, mp, proc, tag);
751 }
752 
753 static void
754 udp_become_writer(conn_t *connp, mblk_t *mp, sqproc_t proc, uint8_t tag)
755 {
756 	udp_t	*udp;
757 
758 	udp = connp->conn_udp;
759 
760 	mutex_enter(&connp->conn_lock);
761 
762 	UDP_MODE_ASSERTIONS(udp, UDP_BECOME_WRITER);
763 
764 	switch (udp->udp_mode) {
765 	case UDP_MT_HOT:
766 		if (udp->udp_reader_count == 1) {
767 			/*
768 			 * We are the only MT thread. Switch to squeue mode
769 			 * immediately.
770 			 */
771 			udp->udp_mode = UDP_SQUEUE;
772 			udp->udp_squeue_count = 1;
773 			CONN_INC_REF_LOCKED(connp);
774 			mutex_exit(&connp->conn_lock);
775 			squeue_enter(connp->conn_sqp, mp, proc, connp, tag);
776 			return;
777 		}
778 		/* FALLTHRU */
779 
780 	case UDP_MT_QUEUED:
781 		/* Enqueue the packet internally in UDP */
782 		udp->udp_mode = UDP_MT_QUEUED;
783 		UDP_ENQUEUE_MP(udp, mp, proc, tag);
784 		mutex_exit(&connp->conn_lock);
785 		return;
786 
787 	case UDP_SQUEUE:
788 	case UDP_QUEUED_SQUEUE:
789 		/*
790 		 * We are already exclusive. i.e. we are already
791 		 * writer. Simply call the desired function.
792 		 */
793 		udp->udp_squeue_count++;
794 		mutex_exit(&connp->conn_lock);
795 		(*proc)(connp, mp, connp->conn_sqp);
796 		return;
797 	}
798 }
799 
800 /*
801  * Transition from MT mode to SQUEUE mode, when the last MT thread
802  * is exiting the UDP perimeter. Move all messages from the internal
803  * udp queue to the squeue. A better way would be to move all the
804  * messages in one shot, this needs more support from the squeue framework
805  */
806 static void
807 udp_switch_to_squeue(udp_t *udp)
808 {
809 	mblk_t *mp;
810 	mblk_t	*mp_next;
811 	sqproc_t proc;
812 	uint8_t	tag;
813 	conn_t	*connp = udp->udp_connp;
814 
815 	ASSERT(MUTEX_HELD(&connp->conn_lock));
816 	ASSERT(udp->udp_mode == UDP_MT_QUEUED);
817 	while (udp->udp_mphead != NULL) {
818 		mp = udp->udp_mphead;
819 		udp->udp_mphead = NULL;
820 		udp->udp_mptail = NULL;
821 		udp->udp_mpcount = 0;
822 		udp->udp_mode = UDP_QUEUED_SQUEUE;
823 		mutex_exit(&connp->conn_lock);
824 		/*
825 		 * It is best not to hold any locks across the calls
826 		 * to squeue functions. Since we drop the lock we
827 		 * need to go back and check the udp_mphead once again
828 		 * after the squeue_fill and hence the while loop at
829 		 * the top of this function
830 		 */
831 		for (; mp != NULL; mp = mp_next) {
832 			mp_next = mp->b_next;
833 			proc = (sqproc_t)mp->b_prev;
834 			tag = (uint8_t)((uintptr_t)mp->b_queue);
835 			mp->b_next = NULL;
836 			mp->b_prev = NULL;
837 			mp->b_queue = NULL;
838 			CONN_INC_REF(connp);
839 			udp->udp_squeue_count++;
840 			squeue_fill(connp->conn_sqp, mp, proc, connp,
841 			    tag);
842 		}
843 		mutex_enter(&connp->conn_lock);
844 	}
845 	/*
846 	 * udp_squeue_count of zero implies that the squeue has drained
847 	 * even before we arrived here (i.e. after the squeue_fill above)
848 	 */
849 	udp->udp_mode = (udp->udp_squeue_count != 0) ?
850 	    UDP_SQUEUE : UDP_MT_HOT;
851 }
852 
853 #define	_UDP_EXIT(connp) {						\
854 	udp_t *_udp = (connp)->conn_udp;				\
855 									\
856 	mutex_enter(&(connp)->conn_lock);				\
857 	UDP_MODE_ASSERTIONS(_udp, UDP_EXIT);				\
858 									\
859 	switch (_udp->udp_mode) {					\
860 	case UDP_MT_HOT:						\
861 		UDP_READERS_DECREF(_udp);				\
862 		mutex_exit(&(connp)->conn_lock);			\
863 		break;							\
864 									\
865 	case UDP_SQUEUE:						\
866 		UDP_SQUEUE_DECREF(_udp);				\
867 		if (_udp->udp_squeue_count == 0)			\
868 		    _udp->udp_mode = UDP_MT_HOT;			\
869 		mutex_exit(&(connp)->conn_lock);			\
870 		break;							\
871 									\
872 	case UDP_MT_QUEUED:						\
873 		/*							\
874 		 * If this is the last MT thread, we need to		\
875 		 * switch to squeue mode				\
876 		 */							\
877 		UDP_READERS_DECREF(_udp);				\
878 		if (_udp->udp_reader_count == 0)			\
879 			udp_switch_to_squeue(_udp);			\
880 		mutex_exit(&(connp)->conn_lock);			\
881 		break;							\
882 									\
883 	case UDP_QUEUED_SQUEUE:						\
884 		UDP_SQUEUE_DECREF(_udp);				\
885 		/*							\
886 		 * Even if the udp_squeue_count drops to zero, we	\
887 		 * don't want to change udp_mode to UDP_MT_HOT here.	\
888 		 * The thread in udp_switch_to_squeue will take care	\
889 		 * of the transition to UDP_MT_HOT, after emptying	\
890 		 * any more new messages that have been enqueued in	\
891 		 * udp_mphead.						\
892 		 */							\
893 		mutex_exit(&(connp)->conn_lock);			\
894 		break;							\
895 	}								\
896 }
897 
898 static void
899 udp_exit(conn_t *connp)
900 {
901 	_UDP_EXIT(connp);
902 }
903 
904 /*
905  * Return the next anonymous port in the priviledged port range for
906  * bind checking.
907  */
908 static in_port_t
909 udp_get_next_priv_port(void)
910 {
911 	static in_port_t next_priv_port = IPPORT_RESERVED - 1;
912 
913 	if (next_priv_port < udp_min_anonpriv_port) {
914 		next_priv_port = IPPORT_RESERVED - 1;
915 	}
916 	return (next_priv_port--);
917 }
918 
919 /* UDP bind hash report triggered via the Named Dispatch mechanism. */
920 /* ARGSUSED */
921 static int
922 udp_bind_hash_report(queue_t *q, mblk_t *mp, caddr_t cp, cred_t *cr)
923 {
924 	udp_fanout_t	*udpf;
925 	int		i;
926 	zoneid_t	zoneid;
927 	conn_t		*connp;
928 	udp_t		*udp;
929 
930 	connp = Q_TO_CONN(q);
931 	udp = connp->conn_udp;
932 
933 	/* Refer to comments in udp_status_report(). */
934 	if (cr == NULL || secpolicy_net_config(cr, B_TRUE) != 0) {
935 		if (ddi_get_lbolt() - udp_last_ndd_get_info_time <
936 		    drv_usectohz(udp_ndd_get_info_interval * 1000)) {
937 			(void) mi_mpprintf(mp, NDD_TOO_QUICK_MSG);
938 			return (0);
939 		}
940 	}
941 	if ((mp->b_cont = allocb(ND_MAX_BUF_LEN, BPRI_HI)) == NULL) {
942 		/* The following may work even if we cannot get a large buf. */
943 		(void) mi_mpprintf(mp, NDD_OUT_OF_BUF_MSG);
944 		return (0);
945 	}
946 
947 	(void) mi_mpprintf(mp,
948 	    "UDP     " MI_COL_HDRPAD_STR
949 	/*   12345678[89ABCDEF] */
950 	    " zone lport src addr        dest addr       port  state");
951 	/*    1234 12345 xxx.xxx.xxx.xxx xxx.xxx.xxx.xxx 12345 UNBOUND */
952 
953 	zoneid = connp->conn_zoneid;
954 
955 	for (i = 0; i < udp_bind_fanout_size; i++) {
956 		udpf = &udp_bind_fanout[i];
957 		mutex_enter(&udpf->uf_lock);
958 
959 		/* Print the hash index. */
960 		udp = udpf->uf_udp;
961 		if (zoneid != GLOBAL_ZONEID) {
962 			/* skip to first entry in this zone; might be none */
963 			while (udp != NULL &&
964 			    udp->udp_connp->conn_zoneid != zoneid)
965 				udp = udp->udp_bind_hash;
966 		}
967 		if (udp != NULL) {
968 			uint_t print_len, buf_len;
969 
970 			buf_len = mp->b_cont->b_datap->db_lim -
971 			    mp->b_cont->b_wptr;
972 			print_len = snprintf((char *)mp->b_cont->b_wptr,
973 			    buf_len, "%d\n", i);
974 			if (print_len < buf_len) {
975 				mp->b_cont->b_wptr += print_len;
976 			} else {
977 				mp->b_cont->b_wptr += buf_len;
978 			}
979 			for (; udp != NULL; udp = udp->udp_bind_hash) {
980 				if (zoneid == GLOBAL_ZONEID ||
981 				    zoneid == udp->udp_connp->conn_zoneid)
982 					udp_report_item(mp->b_cont, udp);
983 			}
984 		}
985 		mutex_exit(&udpf->uf_lock);
986 	}
987 	udp_last_ndd_get_info_time = ddi_get_lbolt();
988 	return (0);
989 }
990 
991 /*
992  * Hash list removal routine for udp_t structures.
993  */
994 static void
995 udp_bind_hash_remove(udp_t *udp, boolean_t caller_holds_lock)
996 {
997 	udp_t	*udpnext;
998 	kmutex_t *lockp;
999 
1000 	if (udp->udp_ptpbhn == NULL)
1001 		return;
1002 
1003 	/*
1004 	 * Extract the lock pointer in case there are concurrent
1005 	 * hash_remove's for this instance.
1006 	 */
1007 	ASSERT(udp->udp_port != 0);
1008 	if (!caller_holds_lock) {
1009 		lockp = &udp_bind_fanout[UDP_BIND_HASH(udp->udp_port)].uf_lock;
1010 		ASSERT(lockp != NULL);
1011 		mutex_enter(lockp);
1012 	}
1013 	if (udp->udp_ptpbhn != NULL) {
1014 		udpnext = udp->udp_bind_hash;
1015 		if (udpnext != NULL) {
1016 			udpnext->udp_ptpbhn = udp->udp_ptpbhn;
1017 			udp->udp_bind_hash = NULL;
1018 		}
1019 		*udp->udp_ptpbhn = udpnext;
1020 		udp->udp_ptpbhn = NULL;
1021 	}
1022 	if (!caller_holds_lock) {
1023 		mutex_exit(lockp);
1024 	}
1025 }
1026 
1027 static void
1028 udp_bind_hash_insert(udp_fanout_t *uf, udp_t *udp)
1029 {
1030 	udp_t	**udpp;
1031 	udp_t	*udpnext;
1032 
1033 	ASSERT(MUTEX_HELD(&uf->uf_lock));
1034 	if (udp->udp_ptpbhn != NULL) {
1035 		udp_bind_hash_remove(udp, B_TRUE);
1036 	}
1037 	udpp = &uf->uf_udp;
1038 	udpnext = udpp[0];
1039 	if (udpnext != NULL) {
1040 		/*
1041 		 * If the new udp bound to the INADDR_ANY address
1042 		 * and the first one in the list is not bound to
1043 		 * INADDR_ANY we skip all entries until we find the
1044 		 * first one bound to INADDR_ANY.
1045 		 * This makes sure that applications binding to a
1046 		 * specific address get preference over those binding to
1047 		 * INADDR_ANY.
1048 		 */
1049 		if (V6_OR_V4_INADDR_ANY(udp->udp_bound_v6src) &&
1050 		    !V6_OR_V4_INADDR_ANY(udpnext->udp_bound_v6src)) {
1051 			while ((udpnext = udpp[0]) != NULL &&
1052 			    !V6_OR_V4_INADDR_ANY(
1053 			    udpnext->udp_bound_v6src)) {
1054 				udpp = &(udpnext->udp_bind_hash);
1055 			}
1056 			if (udpnext != NULL)
1057 				udpnext->udp_ptpbhn = &udp->udp_bind_hash;
1058 		} else {
1059 			udpnext->udp_ptpbhn = &udp->udp_bind_hash;
1060 		}
1061 	}
1062 	udp->udp_bind_hash = udpnext;
1063 	udp->udp_ptpbhn = udpp;
1064 	udpp[0] = udp;
1065 }
1066 
1067 /*
1068  * This routine is called to handle each O_T_BIND_REQ/T_BIND_REQ message
1069  * passed to udp_wput.
1070  * It associates a port number and local address with the stream.
1071  * The O_T_BIND_REQ/T_BIND_REQ is passed downstream to ip with the UDP
1072  * protocol type (IPPROTO_UDP) placed in the message following the address.
1073  * A T_BIND_ACK message is passed upstream when ip acknowledges the request.
1074  * (Called as writer.)
1075  *
1076  * Note that UDP over IPv4 and IPv6 sockets can use the same port number
1077  * without setting SO_REUSEADDR. This is needed so that they
1078  * can be viewed as two independent transport protocols.
1079  * However, anonymouns ports are allocated from the same range to avoid
1080  * duplicating the udp_g_next_port_to_try.
1081  */
1082 static void
1083 udp_bind(queue_t *q, mblk_t *mp)
1084 {
1085 	sin_t		*sin;
1086 	sin6_t		*sin6;
1087 	mblk_t		*mp1;
1088 	in_port_t	port;		/* Host byte order */
1089 	in_port_t	requested_port;	/* Host byte order */
1090 	struct T_bind_req *tbr;
1091 	int		count;
1092 	in6_addr_t	v6src;
1093 	boolean_t	bind_to_req_port_only;
1094 	int		loopmax;
1095 	udp_fanout_t	*udpf;
1096 	in_port_t	lport;		/* Network byte order */
1097 	zoneid_t	zoneid;
1098 	conn_t		*connp;
1099 	udp_t		*udp;
1100 
1101 	connp = Q_TO_CONN(q);
1102 	udp = connp->conn_udp;
1103 	if ((mp->b_wptr - mp->b_rptr) < sizeof (*tbr)) {
1104 		(void) mi_strlog(q, 1, SL_ERROR|SL_TRACE,
1105 		    "udp_bind: bad req, len %u",
1106 		    (uint_t)(mp->b_wptr - mp->b_rptr));
1107 		udp_err_ack(q, mp, TPROTO, 0);
1108 		return;
1109 	}
1110 
1111 	if (udp->udp_state != TS_UNBND) {
1112 		(void) mi_strlog(q, 1, SL_ERROR|SL_TRACE,
1113 		    "udp_bind: bad state, %u", udp->udp_state);
1114 		udp_err_ack(q, mp, TOUTSTATE, 0);
1115 		return;
1116 	}
1117 	/*
1118 	 * Reallocate the message to make sure we have enough room for an
1119 	 * address and the protocol type.
1120 	 */
1121 	mp1 = reallocb(mp, sizeof (struct T_bind_ack) + sizeof (sin6_t) + 1, 1);
1122 	if (!mp1) {
1123 		udp_err_ack(q, mp, TSYSERR, ENOMEM);
1124 		return;
1125 	}
1126 
1127 	mp = mp1;
1128 	tbr = (struct T_bind_req *)mp->b_rptr;
1129 	switch (tbr->ADDR_length) {
1130 	case 0:			/* Request for a generic port */
1131 		tbr->ADDR_offset = sizeof (struct T_bind_req);
1132 		if (udp->udp_family == AF_INET) {
1133 			tbr->ADDR_length = sizeof (sin_t);
1134 			sin = (sin_t *)&tbr[1];
1135 			*sin = sin_null;
1136 			sin->sin_family = AF_INET;
1137 			mp->b_wptr = (uchar_t *)&sin[1];
1138 		} else {
1139 			ASSERT(udp->udp_family == AF_INET6);
1140 			tbr->ADDR_length = sizeof (sin6_t);
1141 			sin6 = (sin6_t *)&tbr[1];
1142 			*sin6 = sin6_null;
1143 			sin6->sin6_family = AF_INET6;
1144 			mp->b_wptr = (uchar_t *)&sin6[1];
1145 		}
1146 		port = 0;
1147 		break;
1148 
1149 	case sizeof (sin_t):	/* Complete IPv4 address */
1150 		sin = (sin_t *)mi_offset_param(mp, tbr->ADDR_offset,
1151 		    sizeof (sin_t));
1152 		if (sin == NULL || !OK_32PTR((char *)sin)) {
1153 			udp_err_ack(q, mp, TSYSERR, EINVAL);
1154 			return;
1155 		}
1156 		if (udp->udp_family != AF_INET ||
1157 		    sin->sin_family != AF_INET) {
1158 			udp_err_ack(q, mp, TSYSERR, EAFNOSUPPORT);
1159 			return;
1160 		}
1161 		port = ntohs(sin->sin_port);
1162 		break;
1163 
1164 	case sizeof (sin6_t):	/* complete IPv6 address */
1165 		sin6 = (sin6_t *)mi_offset_param(mp, tbr->ADDR_offset,
1166 		    sizeof (sin6_t));
1167 		if (sin6 == NULL || !OK_32PTR((char *)sin6)) {
1168 			udp_err_ack(q, mp, TSYSERR, EINVAL);
1169 			return;
1170 		}
1171 		if (udp->udp_family != AF_INET6 ||
1172 		    sin6->sin6_family != AF_INET6) {
1173 			udp_err_ack(q, mp, TSYSERR, EAFNOSUPPORT);
1174 			return;
1175 		}
1176 		port = ntohs(sin6->sin6_port);
1177 		break;
1178 
1179 	default:		/* Invalid request */
1180 		(void) mi_strlog(q, 1, SL_ERROR|SL_TRACE,
1181 		    "udp_bind: bad ADDR_length length %u", tbr->ADDR_length);
1182 		udp_err_ack(q, mp, TBADADDR, 0);
1183 		return;
1184 	}
1185 
1186 	requested_port = port;
1187 
1188 	if (requested_port == 0 || tbr->PRIM_type == O_T_BIND_REQ)
1189 		bind_to_req_port_only = B_FALSE;
1190 	else			/* T_BIND_REQ and requested_port != 0 */
1191 		bind_to_req_port_only = B_TRUE;
1192 
1193 	if (requested_port == 0) {
1194 		/*
1195 		 * If the application passed in zero for the port number, it
1196 		 * doesn't care which port number we bind to. Get one in the
1197 		 * valid range.
1198 		 */
1199 		if (udp->udp_anon_priv_bind) {
1200 			port = udp_get_next_priv_port();
1201 		} else {
1202 			port = udp_update_next_port(udp_g_next_port_to_try,
1203 			    B_TRUE);
1204 		}
1205 	} else {
1206 		/*
1207 		 * If the port is in the well-known privileged range,
1208 		 * make sure the caller was privileged.
1209 		 */
1210 		int i;
1211 		boolean_t priv = B_FALSE;
1212 
1213 		if (port < udp_smallest_nonpriv_port) {
1214 			priv = B_TRUE;
1215 		} else {
1216 			for (i = 0; i < udp_g_num_epriv_ports; i++) {
1217 				if (port == udp_g_epriv_ports[i]) {
1218 					priv = B_TRUE;
1219 					break;
1220 				}
1221 			}
1222 		}
1223 
1224 		if (priv) {
1225 			cred_t *cr = DB_CREDDEF(mp, connp->conn_cred);
1226 
1227 			if (secpolicy_net_privaddr(cr, port) != 0) {
1228 				udp_err_ack(q, mp, TACCES, 0);
1229 				return;
1230 			}
1231 		}
1232 	}
1233 
1234 	/*
1235 	 * Copy the source address into our udp structure. This address
1236 	 * may still be zero; if so, IP will fill in the correct address
1237 	 * each time an outbound packet is passed to it.
1238 	 */
1239 	if (udp->udp_family == AF_INET) {
1240 		ASSERT(sin != NULL);
1241 		ASSERT(udp->udp_ipversion == IPV4_VERSION);
1242 		udp->udp_max_hdr_len = IP_SIMPLE_HDR_LENGTH + UDPH_SIZE +
1243 		    udp->udp_ip_snd_options_len;
1244 		IN6_IPADDR_TO_V4MAPPED(sin->sin_addr.s_addr, &v6src);
1245 	} else {
1246 		ASSERT(sin6 != NULL);
1247 		v6src = sin6->sin6_addr;
1248 		if (IN6_IS_ADDR_V4MAPPED(&v6src)) {
1249 			udp->udp_ipversion = IPV4_VERSION;
1250 			udp->udp_max_hdr_len = IP_SIMPLE_HDR_LENGTH +
1251 			    UDPH_SIZE + udp->udp_ip_snd_options_len;
1252 		} else {
1253 			udp->udp_ipversion = IPV6_VERSION;
1254 			udp->udp_max_hdr_len = udp->udp_sticky_hdrs_len;
1255 		}
1256 	}
1257 
1258 	/*
1259 	 * If udp_reuseaddr is not set, then we have to make sure that
1260 	 * the IP address and port number the application requested
1261 	 * (or we selected for the application) is not being used by
1262 	 * another stream.  If another stream is already using the
1263 	 * requested IP address and port, the behavior depends on
1264 	 * "bind_to_req_port_only". If set the bind fails; otherwise we
1265 	 * search for any an unused port to bind to the the stream.
1266 	 *
1267 	 * As per the BSD semantics, as modified by the Deering multicast
1268 	 * changes, if udp_reuseaddr is set, then we allow multiple binds
1269 	 * to the same port independent of the local IP address.
1270 	 *
1271 	 * This is slightly different than in SunOS 4.X which did not
1272 	 * support IP multicast. Note that the change implemented by the
1273 	 * Deering multicast code effects all binds - not only binding
1274 	 * to IP multicast addresses.
1275 	 *
1276 	 * Note that when binding to port zero we ignore SO_REUSEADDR in
1277 	 * order to guarantee a unique port.
1278 	 */
1279 
1280 	count = 0;
1281 	if (udp->udp_anon_priv_bind) {
1282 		/* loopmax = (IPPORT_RESERVED-1) - udp_min_anonpriv_port + 1 */
1283 		loopmax = IPPORT_RESERVED - udp_min_anonpriv_port;
1284 	} else {
1285 		loopmax = udp_largest_anon_port - udp_smallest_anon_port + 1;
1286 	}
1287 
1288 	zoneid = connp->conn_zoneid;
1289 	for (;;) {
1290 		udp_t		*udp1;
1291 		boolean_t	is_inaddr_any;
1292 		boolean_t	found_exclbind = B_FALSE;
1293 
1294 		is_inaddr_any = V6_OR_V4_INADDR_ANY(v6src);
1295 		/*
1296 		 * Walk through the list of udp streams bound to
1297 		 * requested port with the same IP address.
1298 		 */
1299 		lport = htons(port);
1300 		udpf = &udp_bind_fanout[UDP_BIND_HASH(lport)];
1301 		mutex_enter(&udpf->uf_lock);
1302 		for (udp1 = udpf->uf_udp; udp1 != NULL;
1303 		    udp1 = udp1->udp_bind_hash) {
1304 			if (lport != udp1->udp_port ||
1305 			    zoneid != udp1->udp_connp->conn_zoneid)
1306 				continue;
1307 
1308 			/*
1309 			 * If UDP_EXCLBIND is set for either the bound or
1310 			 * binding endpoint, the semantics of bind
1311 			 * is changed according to the following chart.
1312 			 *
1313 			 * spec = specified address (v4 or v6)
1314 			 * unspec = unspecified address (v4 or v6)
1315 			 * A = specified addresses are different for endpoints
1316 			 *
1317 			 * bound	bind to		allowed?
1318 			 * -------------------------------------
1319 			 * unspec	unspec		no
1320 			 * unspec	spec		no
1321 			 * spec		unspec		no
1322 			 * spec		spec		yes if A
1323 			 */
1324 			if (udp1->udp_exclbind || udp->udp_exclbind) {
1325 				if (V6_OR_V4_INADDR_ANY(
1326 				    udp1->udp_bound_v6src) ||
1327 				    is_inaddr_any ||
1328 				    IN6_ARE_ADDR_EQUAL(&udp1->udp_bound_v6src,
1329 				    &v6src)) {
1330 					found_exclbind = B_TRUE;
1331 					break;
1332 				}
1333 				continue;
1334 			}
1335 
1336 			/*
1337 			 * Check ipversion to allow IPv4 and IPv6 sockets to
1338 			 * have disjoint port number spaces.
1339 			 */
1340 			if (udp->udp_ipversion != udp1->udp_ipversion)
1341 				continue;
1342 
1343 			/*
1344 			 * No difference depending on SO_REUSEADDR.
1345 			 *
1346 			 * If existing port is bound to a
1347 			 * non-wildcard IP address and
1348 			 * the requesting stream is bound to
1349 			 * a distinct different IP addresses
1350 			 * (non-wildcard, also), keep going.
1351 			 */
1352 			if (!is_inaddr_any &&
1353 			    !V6_OR_V4_INADDR_ANY(udp1->udp_bound_v6src) &&
1354 			    !IN6_ARE_ADDR_EQUAL(&udp1->udp_bound_v6src,
1355 			    &v6src)) {
1356 				continue;
1357 			}
1358 			break;
1359 		}
1360 
1361 		if (!found_exclbind &&
1362 		    (udp->udp_reuseaddr && requested_port != 0)) {
1363 			break;
1364 		}
1365 
1366 		if (udp1 == NULL) {
1367 			/*
1368 			 * No other stream has this IP address
1369 			 * and port number. We can use it.
1370 			 */
1371 			break;
1372 		}
1373 		mutex_exit(&udpf->uf_lock);
1374 		if (bind_to_req_port_only) {
1375 			/*
1376 			 * We get here only when requested port
1377 			 * is bound (and only first  of the for()
1378 			 * loop iteration).
1379 			 *
1380 			 * The semantics of this bind request
1381 			 * require it to fail so we return from
1382 			 * the routine (and exit the loop).
1383 			 *
1384 			 */
1385 			udp_err_ack(q, mp, TADDRBUSY, 0);
1386 			return;
1387 		}
1388 
1389 		if (udp->udp_anon_priv_bind) {
1390 			port = udp_get_next_priv_port();
1391 		} else {
1392 			if ((count == 0) && (requested_port != 0)) {
1393 				/*
1394 				 * If the application wants us to find
1395 				 * a port, get one to start with. Set
1396 				 * requested_port to 0, so that we will
1397 				 * update udp_g_next_port_to_try below.
1398 				 */
1399 				port = udp_update_next_port(
1400 				    udp_g_next_port_to_try, B_TRUE);
1401 				requested_port = 0;
1402 			} else {
1403 				port = udp_update_next_port(port + 1, B_FALSE);
1404 			}
1405 		}
1406 
1407 		if (++count >= loopmax) {
1408 			/*
1409 			 * We've tried every possible port number and
1410 			 * there are none available, so send an error
1411 			 * to the user.
1412 			 */
1413 			udp_err_ack(q, mp, TNOADDR, 0);
1414 			return;
1415 		}
1416 	}
1417 
1418 	/*
1419 	 * Copy the source address into our udp structure.  This address
1420 	 * may still be zero; if so, ip will fill in the correct address
1421 	 * each time an outbound packet is passed to it.
1422 	 * If we are binding to a broadcast or multicast address udp_rput
1423 	 * will clear the source address when it receives the T_BIND_ACK.
1424 	 */
1425 	udp->udp_v6src = udp->udp_bound_v6src = v6src;
1426 	udp->udp_port = lport;
1427 	/*
1428 	 * Now reset the the next anonymous port if the application requested
1429 	 * an anonymous port, or we handed out the next anonymous port.
1430 	 */
1431 	if ((requested_port == 0) && (!udp->udp_anon_priv_bind)) {
1432 		udp_g_next_port_to_try = port + 1;
1433 	}
1434 
1435 	/* Initialize the O_T_BIND_REQ/T_BIND_REQ for ip. */
1436 	if (udp->udp_family == AF_INET) {
1437 		sin->sin_port = udp->udp_port;
1438 	} else {
1439 		int error;
1440 
1441 		sin6->sin6_port = udp->udp_port;
1442 		/* Rebuild the header template */
1443 		error = udp_build_hdrs(q, udp);
1444 		if (error != 0) {
1445 			mutex_exit(&udpf->uf_lock);
1446 			udp_err_ack(q, mp, TSYSERR, error);
1447 			return;
1448 		}
1449 	}
1450 	udp->udp_state = TS_IDLE;
1451 	udp_bind_hash_insert(udpf, udp);
1452 	mutex_exit(&udpf->uf_lock);
1453 
1454 	if (cl_inet_bind) {
1455 		/*
1456 		 * Running in cluster mode - register bind information
1457 		 */
1458 		if (udp->udp_ipversion == IPV4_VERSION) {
1459 			(*cl_inet_bind)(IPPROTO_UDP, AF_INET,
1460 			    (uint8_t *)(&V4_PART_OF_V6(udp->udp_v6src)),
1461 			    (in_port_t)udp->udp_port);
1462 		} else {
1463 			(*cl_inet_bind)(IPPROTO_UDP, AF_INET6,
1464 			    (uint8_t *)&(udp->udp_v6src),
1465 			    (in_port_t)udp->udp_port);
1466 		}
1467 
1468 	}
1469 
1470 	/* Pass the protocol number in the message following the address. */
1471 	*mp->b_wptr++ = IPPROTO_UDP;
1472 	if (!V6_OR_V4_INADDR_ANY(udp->udp_v6src)) {
1473 		/*
1474 		 * Append a request for an IRE if udp_v6src not
1475 		 * zero (IPv4 - INADDR_ANY, or IPv6 - all-zeroes address).
1476 		 */
1477 		mp->b_cont = allocb(sizeof (ire_t), BPRI_HI);
1478 		if (!mp->b_cont) {
1479 			udp_err_ack(q, mp, TSYSERR, ENOMEM);
1480 			return;
1481 		}
1482 		mp->b_cont->b_wptr += sizeof (ire_t);
1483 		mp->b_cont->b_datap->db_type = IRE_DB_REQ_TYPE;
1484 	}
1485 	if (udp->udp_family == AF_INET6)
1486 		mp = ip_bind_v6(q, mp, connp, NULL);
1487 	else
1488 		mp = ip_bind_v4(q, mp, connp);
1489 
1490 	if (mp != NULL)
1491 		udp_rput_other(_RD(q), mp);
1492 	else
1493 		CONN_INC_REF(connp);
1494 }
1495 
1496 
1497 void
1498 udp_resume_bind(conn_t *connp, mblk_t *mp)
1499 {
1500 	udp_enter(connp, mp, udp_resume_bind_cb, SQTAG_BIND_RETRY);
1501 }
1502 
1503 /*
1504  * This is called from ip_wput_nondata to resume a deferred UDP bind.
1505  */
1506 /* ARGSUSED */
1507 static void
1508 udp_resume_bind_cb(void *arg, mblk_t *mp, void *arg2)
1509 {
1510 	conn_t *connp = arg;
1511 
1512 	ASSERT(connp != NULL && IPCL_IS_UDP(connp));
1513 
1514 	udp_rput_other(connp->conn_rq, mp);
1515 
1516 	CONN_OPER_PENDING_DONE(connp);
1517 	udp_exit(connp);
1518 }
1519 
1520 /*
1521  * This routine handles each T_CONN_REQ message passed to udp.  It
1522  * associates a default destination address with the stream.
1523  *
1524  * This routine sends down a T_BIND_REQ to IP with the following mblks:
1525  *	T_BIND_REQ	- specifying local and remote address/port
1526  *	IRE_DB_REQ_TYPE	- to get an IRE back containing ire_type and src
1527  *	T_OK_ACK	- for the T_CONN_REQ
1528  *	T_CONN_CON	- to keep the TPI user happy
1529  *
1530  * The connect completes in udp_rput.
1531  * When a T_BIND_ACK is received information is extracted from the IRE
1532  * and the two appended messages are sent to the TPI user.
1533  * Should udp_rput receive T_ERROR_ACK for the T_BIND_REQ it will convert
1534  * it to an error ack for the appropriate primitive.
1535  */
1536 static void
1537 udp_connect(queue_t *q, mblk_t *mp)
1538 {
1539 	sin6_t	*sin6;
1540 	sin_t	*sin;
1541 	struct T_conn_req	*tcr;
1542 	in6_addr_t v6dst;
1543 	ipaddr_t v4dst;
1544 	uint16_t dstport;
1545 	uint32_t flowinfo;
1546 	mblk_t	*mp1, *mp2;
1547 	udp_fanout_t	*udpf;
1548 	udp_t	*udp, *udp1;
1549 
1550 	udp = Q_TO_UDP(q);
1551 
1552 	tcr = (struct T_conn_req *)mp->b_rptr;
1553 
1554 	/* A bit of sanity checking */
1555 	if ((mp->b_wptr - mp->b_rptr) < sizeof (struct T_conn_req)) {
1556 		udp_err_ack(q, mp, TPROTO, 0);
1557 		return;
1558 	}
1559 	/*
1560 	 * This UDP must have bound to a port already before doing
1561 	 * a connect.
1562 	 */
1563 	if (udp->udp_state == TS_UNBND) {
1564 		(void) mi_strlog(q, 1, SL_ERROR|SL_TRACE,
1565 		    "udp_connect: bad state, %u", udp->udp_state);
1566 		udp_err_ack(q, mp, TOUTSTATE, 0);
1567 		return;
1568 	}
1569 	ASSERT(udp->udp_port != 0 && udp->udp_ptpbhn != NULL);
1570 
1571 	udpf = &udp_bind_fanout[UDP_BIND_HASH(udp->udp_port)];
1572 
1573 	if (udp->udp_state == TS_DATA_XFER) {
1574 		/* Already connected - clear out state */
1575 		mutex_enter(&udpf->uf_lock);
1576 		udp->udp_v6src = udp->udp_bound_v6src;
1577 		udp->udp_state = TS_IDLE;
1578 		mutex_exit(&udpf->uf_lock);
1579 	}
1580 
1581 	if (tcr->OPT_length != 0) {
1582 		udp_err_ack(q, mp, TBADOPT, 0);
1583 		return;
1584 	}
1585 
1586 	/*
1587 	 * Determine packet type based on type of address passed in
1588 	 * the request should contain an IPv4 or IPv6 address.
1589 	 * Make sure that address family matches the type of
1590 	 * family of the the address passed down
1591 	 */
1592 	switch (tcr->DEST_length) {
1593 	default:
1594 		udp_err_ack(q, mp, TBADADDR, 0);
1595 		return;
1596 
1597 	case sizeof (sin_t):
1598 		sin = (sin_t *)mi_offset_param(mp, tcr->DEST_offset,
1599 		    sizeof (sin_t));
1600 		if (sin == NULL || !OK_32PTR((char *)sin)) {
1601 			udp_err_ack(q, mp, TSYSERR, EINVAL);
1602 			return;
1603 		}
1604 		if (udp->udp_family != AF_INET ||
1605 		    sin->sin_family != AF_INET) {
1606 			udp_err_ack(q, mp, TSYSERR, EAFNOSUPPORT);
1607 			return;
1608 		}
1609 		v4dst = sin->sin_addr.s_addr;
1610 		dstport = sin->sin_port;
1611 		IN6_IPADDR_TO_V4MAPPED(v4dst, &v6dst);
1612 		ASSERT(udp->udp_ipversion == IPV4_VERSION);
1613 		udp->udp_max_hdr_len = IP_SIMPLE_HDR_LENGTH + UDPH_SIZE +
1614 		    udp->udp_ip_snd_options_len;
1615 		break;
1616 
1617 	case sizeof (sin6_t):
1618 		sin6 = (sin6_t *)mi_offset_param(mp, tcr->DEST_offset,
1619 		    sizeof (sin6_t));
1620 		if (sin6 == NULL || !OK_32PTR((char *)sin6)) {
1621 			udp_err_ack(q, mp, TSYSERR, EINVAL);
1622 			return;
1623 		}
1624 		if (udp->udp_family != AF_INET6 ||
1625 		    sin6->sin6_family != AF_INET6) {
1626 			udp_err_ack(q, mp, TSYSERR, EAFNOSUPPORT);
1627 			return;
1628 		}
1629 		v6dst = sin6->sin6_addr;
1630 		if (IN6_IS_ADDR_V4MAPPED(&v6dst)) {
1631 			IN6_V4MAPPED_TO_IPADDR(&v6dst, v4dst);
1632 			udp->udp_ipversion = IPV4_VERSION;
1633 			udp->udp_max_hdr_len = IP_SIMPLE_HDR_LENGTH +
1634 			    UDPH_SIZE + udp->udp_ip_snd_options_len;
1635 			flowinfo = 0;
1636 		} else {
1637 			udp->udp_ipversion = IPV6_VERSION;
1638 			udp->udp_max_hdr_len = udp->udp_sticky_hdrs_len;
1639 			flowinfo = sin6->sin6_flowinfo;
1640 		}
1641 		dstport = sin6->sin6_port;
1642 		break;
1643 	}
1644 	if (dstport == 0) {
1645 		udp_err_ack(q, mp, TBADADDR, 0);
1646 		return;
1647 	}
1648 
1649 	/*
1650 	 * Create a default IP header with no IP options.
1651 	 */
1652 	udp->udp_dstport = dstport;
1653 	if (udp->udp_ipversion == IPV4_VERSION) {
1654 		/*
1655 		 * Interpret a zero destination to mean loopback.
1656 		 * Update the T_CONN_REQ (sin/sin6) since it is used to
1657 		 * generate the T_CONN_CON.
1658 		 */
1659 		if (v4dst == INADDR_ANY) {
1660 			v4dst = htonl(INADDR_LOOPBACK);
1661 			IN6_IPADDR_TO_V4MAPPED(v4dst, &v6dst);
1662 			if (udp->udp_family == AF_INET) {
1663 				sin->sin_addr.s_addr = v4dst;
1664 			} else {
1665 				sin6->sin6_addr = v6dst;
1666 			}
1667 		}
1668 		udp->udp_v6dst = v6dst;
1669 		udp->udp_flowinfo = 0;
1670 
1671 		/*
1672 		 * If the destination address is multicast and
1673 		 * an outgoing multicast interface has been set,
1674 		 * use the address of that interface as our
1675 		 * source address if no source address has been set.
1676 		 */
1677 		if (V4_PART_OF_V6(udp->udp_v6src) == INADDR_ANY &&
1678 		    CLASSD(v4dst) &&
1679 		    udp->udp_multicast_if_addr != INADDR_ANY) {
1680 			IN6_IPADDR_TO_V4MAPPED(udp->udp_multicast_if_addr,
1681 			    &udp->udp_v6src);
1682 		}
1683 	} else {
1684 		ASSERT(udp->udp_ipversion == IPV6_VERSION);
1685 		/*
1686 		 * Interpret a zero destination to mean loopback.
1687 		 * Update the T_CONN_REQ (sin/sin6) since it is used to
1688 		 * generate the T_CONN_CON.
1689 		 */
1690 		if (IN6_IS_ADDR_UNSPECIFIED(&v6dst)) {
1691 			v6dst = ipv6_loopback;
1692 			sin6->sin6_addr = v6dst;
1693 		}
1694 		udp->udp_v6dst = v6dst;
1695 		udp->udp_flowinfo = flowinfo;
1696 		/*
1697 		 * If the destination address is multicast and
1698 		 * an outgoing multicast interface has been set,
1699 		 * then the ip bind logic will pick the correct source
1700 		 * address (i.e. matching the outgoing multicast interface).
1701 		 */
1702 	}
1703 
1704 	/*
1705 	 * Verify that the src/port/dst/port is unique for all
1706 	 * connections in TS_DATA_XFER
1707 	 */
1708 	mutex_enter(&udpf->uf_lock);
1709 	for (udp1 = udpf->uf_udp; udp1 != NULL; udp1 = udp1->udp_bind_hash) {
1710 		if (udp1->udp_state != TS_DATA_XFER)
1711 			continue;
1712 		if (udp->udp_port != udp1->udp_port ||
1713 		    udp->udp_ipversion != udp1->udp_ipversion ||
1714 		    dstport != udp1->udp_dstport ||
1715 		    !IN6_ARE_ADDR_EQUAL(&udp->udp_v6src, &udp1->udp_v6src) ||
1716 		    !IN6_ARE_ADDR_EQUAL(&v6dst, &udp1->udp_v6dst))
1717 			continue;
1718 		mutex_exit(&udpf->uf_lock);
1719 		udp_err_ack(q, mp, TBADADDR, 0);
1720 		return;
1721 	}
1722 	udp->udp_state = TS_DATA_XFER;
1723 	mutex_exit(&udpf->uf_lock);
1724 
1725 	/*
1726 	 * Send down bind to IP to verify that there is a route
1727 	 * and to determine the source address.
1728 	 * This will come back as T_BIND_ACK with an IRE_DB_TYPE in rput.
1729 	 */
1730 	if (udp->udp_family == AF_INET)
1731 		mp1 = udp_ip_bind_mp(udp, O_T_BIND_REQ, sizeof (ipa_conn_t));
1732 	else
1733 		mp1 = udp_ip_bind_mp(udp, O_T_BIND_REQ, sizeof (ipa6_conn_t));
1734 	if (mp1 == NULL) {
1735 		udp_err_ack(q, mp, TSYSERR, ENOMEM);
1736 bind_failed:
1737 		mutex_enter(&udpf->uf_lock);
1738 		udp->udp_state = TS_IDLE;
1739 		mutex_exit(&udpf->uf_lock);
1740 		return;
1741 	}
1742 
1743 	/*
1744 	 * We also have to send a connection confirmation to
1745 	 * keep TLI happy. Prepare it for udp_rput.
1746 	 */
1747 	if (udp->udp_family == AF_INET)
1748 		mp2 = mi_tpi_conn_con(NULL, (char *)sin,
1749 		    sizeof (*sin), NULL, 0);
1750 	else
1751 		mp2 = mi_tpi_conn_con(NULL, (char *)sin6,
1752 		    sizeof (*sin6), NULL, 0);
1753 	if (mp2 == NULL) {
1754 		freemsg(mp1);
1755 		udp_err_ack(q, mp, TSYSERR, ENOMEM);
1756 		goto bind_failed;
1757 	}
1758 
1759 	mp = mi_tpi_ok_ack_alloc(mp);
1760 	if (mp == NULL) {
1761 		/* Unable to reuse the T_CONN_REQ for the ack. */
1762 		freemsg(mp2);
1763 		udp_err_ack_prim(q, mp1, T_CONN_REQ, TSYSERR, ENOMEM);
1764 		goto bind_failed;
1765 	}
1766 
1767 	/* Hang onto the T_OK_ACK and T_CONN_CON for later. */
1768 	linkb(mp1, mp);
1769 	linkb(mp1, mp2);
1770 
1771 	if (udp->udp_family == AF_INET)
1772 		mp1 = ip_bind_v4(q, mp1, udp->udp_connp);
1773 	else
1774 		mp1 = ip_bind_v6(q, mp1, udp->udp_connp, NULL);
1775 
1776 	if (mp1 != NULL)
1777 		udp_rput_other(_RD(q), mp1);
1778 	else
1779 		CONN_INC_REF(udp->udp_connp);
1780 }
1781 
1782 static int
1783 udp_close(queue_t *q)
1784 {
1785 	conn_t	*connp = Q_TO_CONN(UDP_WR(q));
1786 	udp_t	*udp;
1787 	queue_t	*ip_rq = RD(UDP_WR(q));
1788 
1789 	ASSERT(connp != NULL && IPCL_IS_UDP(connp));
1790 	udp = connp->conn_udp;
1791 
1792 	ip_quiesce_conn(connp);
1793 	/*
1794 	 * Disable read-side synchronous stream
1795 	 * interface and drain any queued data.
1796 	 */
1797 	udp_rcv_drain(q, udp, B_TRUE);
1798 	ASSERT(!udp->udp_direct_sockfs);
1799 
1800 	qprocsoff(q);
1801 
1802 	/* restore IP module's high and low water marks to default values */
1803 	ip_rq->q_hiwat = ip_rq->q_qinfo->qi_minfo->mi_hiwat;
1804 	WR(ip_rq)->q_hiwat = WR(ip_rq)->q_qinfo->qi_minfo->mi_hiwat;
1805 	WR(ip_rq)->q_lowat = WR(ip_rq)->q_qinfo->qi_minfo->mi_lowat;
1806 
1807 	ASSERT(udp->udp_rcv_cnt == 0);
1808 	ASSERT(udp->udp_rcv_msgcnt == 0);
1809 	ASSERT(udp->udp_rcv_list_head == NULL);
1810 	ASSERT(udp->udp_rcv_list_tail == NULL);
1811 
1812 	/* connp is now single threaded. */
1813 	udp_close_free(connp);
1814 	/*
1815 	 * Restore connp as an IP endpoint.  We don't need
1816 	 * any locks since we are now single threaded
1817 	 */
1818 	connp->conn_flags &= ~IPCL_UDP;
1819 	connp->conn_state_flags &=
1820 	    ~(CONN_CLOSING | CONN_CONDEMNED | CONN_QUIESCED);
1821 	return (0);
1822 }
1823 
1824 /*
1825  * Called in the close path from IP (ip_quiesce_conn) to quiesce the conn
1826  */
1827 void
1828 udp_quiesce_conn(conn_t *connp)
1829 {
1830 	udp_t	*udp = connp->conn_udp;
1831 
1832 	if (cl_inet_unbind != NULL && udp->udp_state == TS_IDLE) {
1833 		/*
1834 		 * Running in cluster mode - register unbind information
1835 		 */
1836 		if (udp->udp_ipversion == IPV4_VERSION) {
1837 			(*cl_inet_unbind)(IPPROTO_UDP, AF_INET,
1838 			    (uint8_t *)(&(V4_PART_OF_V6(udp->udp_v6src))),
1839 			    (in_port_t)udp->udp_port);
1840 		} else {
1841 			(*cl_inet_unbind)(IPPROTO_UDP, AF_INET6,
1842 			    (uint8_t *)(&(udp->udp_v6src)),
1843 			    (in_port_t)udp->udp_port);
1844 		}
1845 	}
1846 
1847 	udp_bind_hash_remove(udp, B_FALSE);
1848 
1849 	mutex_enter(&connp->conn_lock);
1850 	while (udp->udp_reader_count != 0 || udp->udp_squeue_count != 0 ||
1851 	    udp->udp_mode != UDP_MT_HOT) {
1852 		cv_wait(&connp->conn_cv, &connp->conn_lock);
1853 	}
1854 	mutex_exit(&connp->conn_lock);
1855 }
1856 
1857 void
1858 udp_close_free(conn_t *connp)
1859 {
1860 	udp_t *udp = connp->conn_udp;
1861 
1862 	/* If there are any options associated with the stream, free them. */
1863 	if (udp->udp_ip_snd_options) {
1864 		mi_free((char *)udp->udp_ip_snd_options);
1865 		udp->udp_ip_snd_options = NULL;
1866 	}
1867 
1868 	if (udp->udp_ip_rcv_options) {
1869 		mi_free((char *)udp->udp_ip_rcv_options);
1870 		udp->udp_ip_rcv_options = NULL;
1871 	}
1872 
1873 	/* Free memory associated with sticky options */
1874 	if (udp->udp_sticky_hdrs_len != 0) {
1875 		kmem_free(udp->udp_sticky_hdrs,
1876 		    udp->udp_sticky_hdrs_len);
1877 		udp->udp_sticky_hdrs = NULL;
1878 		udp->udp_sticky_hdrs_len = 0;
1879 	}
1880 
1881 	if (udp->udp_sticky_ipp.ipp_fields & IPPF_HOPOPTS) {
1882 		kmem_free(udp->udp_sticky_ipp.ipp_hopopts,
1883 		    udp->udp_sticky_ipp.ipp_hopoptslen);
1884 		udp->udp_sticky_ipp.ipp_hopopts = NULL;
1885 	}
1886 	if (udp->udp_sticky_ipp.ipp_fields & IPPF_RTDSTOPTS) {
1887 		kmem_free(udp->udp_sticky_ipp.ipp_rtdstopts,
1888 		    udp->udp_sticky_ipp.ipp_rtdstoptslen);
1889 		udp->udp_sticky_ipp.ipp_rtdstopts = NULL;
1890 	}
1891 	if (udp->udp_sticky_ipp.ipp_fields & IPPF_RTHDR) {
1892 		kmem_free(udp->udp_sticky_ipp.ipp_rthdr,
1893 		    udp->udp_sticky_ipp.ipp_rthdrlen);
1894 		udp->udp_sticky_ipp.ipp_rthdr = NULL;
1895 	}
1896 	if (udp->udp_sticky_ipp.ipp_fields & IPPF_DSTOPTS) {
1897 		kmem_free(udp->udp_sticky_ipp.ipp_dstopts,
1898 		    udp->udp_sticky_ipp.ipp_dstoptslen);
1899 		udp->udp_sticky_ipp.ipp_dstopts = NULL;
1900 	}
1901 	udp->udp_sticky_ipp.ipp_fields &=
1902 	    ~(IPPF_HOPOPTS|IPPF_RTDSTOPTS|IPPF_RTHDR|IPPF_DSTOPTS);
1903 
1904 	udp->udp_connp = NULL;
1905 	connp->conn_udp = NULL;
1906 	kmem_cache_free(udp_cache, udp);
1907 }
1908 
1909 /*
1910  * This routine handles each T_DISCON_REQ message passed to udp
1911  * as an indicating that UDP is no longer connected. This results
1912  * in sending a T_BIND_REQ to IP to restore the binding to just
1913  * the local address/port.
1914  *
1915  * This routine sends down a T_BIND_REQ to IP with the following mblks:
1916  *	T_BIND_REQ	- specifying just the local address/port
1917  *	T_OK_ACK	- for the T_DISCON_REQ
1918  *
1919  * The disconnect completes in udp_rput.
1920  * When a T_BIND_ACK is received the appended T_OK_ACK is sent to the TPI user.
1921  * Should udp_rput receive T_ERROR_ACK for the T_BIND_REQ it will convert
1922  * it to an error ack for the appropriate primitive.
1923  */
1924 static void
1925 udp_disconnect(queue_t *q, mblk_t *mp)
1926 {
1927 	udp_t	*udp = Q_TO_UDP(q);
1928 	mblk_t	*mp1;
1929 	udp_fanout_t *udpf;
1930 
1931 	if (udp->udp_state != TS_DATA_XFER) {
1932 		(void) mi_strlog(q, 1, SL_ERROR|SL_TRACE,
1933 		    "udp_disconnect: bad state, %u", udp->udp_state);
1934 		udp_err_ack(q, mp, TOUTSTATE, 0);
1935 		return;
1936 	}
1937 	udpf = &udp_bind_fanout[UDP_BIND_HASH(udp->udp_port)];
1938 	mutex_enter(&udpf->uf_lock);
1939 	udp->udp_v6src = udp->udp_bound_v6src;
1940 	udp->udp_state = TS_IDLE;
1941 	mutex_exit(&udpf->uf_lock);
1942 
1943 	/*
1944 	 * Send down bind to IP to remove the full binding and revert
1945 	 * to the local address binding.
1946 	 */
1947 	if (udp->udp_family == AF_INET)
1948 		mp1 = udp_ip_bind_mp(udp, O_T_BIND_REQ, sizeof (sin_t));
1949 	else
1950 		mp1 = udp_ip_bind_mp(udp, O_T_BIND_REQ, sizeof (sin6_t));
1951 	if (mp1 == NULL) {
1952 		udp_err_ack(q, mp, TSYSERR, ENOMEM);
1953 		return;
1954 	}
1955 	mp = mi_tpi_ok_ack_alloc(mp);
1956 	if (mp == NULL) {
1957 		/* Unable to reuse the T_DISCON_REQ for the ack. */
1958 		udp_err_ack_prim(q, mp1, T_DISCON_REQ, TSYSERR, ENOMEM);
1959 		return;
1960 	}
1961 
1962 	if (udp->udp_family == AF_INET6) {
1963 		int error;
1964 
1965 		/* Rebuild the header template */
1966 		error = udp_build_hdrs(q, udp);
1967 		if (error != 0) {
1968 			udp_err_ack_prim(q, mp, T_DISCON_REQ, TSYSERR, error);
1969 			freemsg(mp1);
1970 			return;
1971 		}
1972 	}
1973 	mutex_enter(&udpf->uf_lock);
1974 	udp->udp_discon_pending = 1;
1975 	mutex_exit(&udpf->uf_lock);
1976 
1977 	/* Append the T_OK_ACK to the T_BIND_REQ for udp_rput */
1978 	linkb(mp1, mp);
1979 
1980 	if (udp->udp_family == AF_INET6)
1981 		mp1 = ip_bind_v6(q, mp1, udp->udp_connp, NULL);
1982 	else
1983 		mp1 = ip_bind_v4(q, mp1, udp->udp_connp);
1984 
1985 	if (mp1 != NULL)
1986 		udp_rput_other(_RD(q), mp1);
1987 	else
1988 		CONN_INC_REF(udp->udp_connp);
1989 }
1990 
1991 /* This routine creates a T_ERROR_ACK message and passes it upstream. */
1992 static void
1993 udp_err_ack(queue_t *q, mblk_t *mp, t_scalar_t t_error, int sys_error)
1994 {
1995 	if ((mp = mi_tpi_err_ack_alloc(mp, t_error, sys_error)) != NULL)
1996 		putnext(UDP_RD(q), mp);
1997 }
1998 
1999 /* Shorthand to generate and send TPI error acks to our client */
2000 static void
2001 udp_err_ack_prim(queue_t *q, mblk_t *mp, int primitive, t_scalar_t t_error,
2002     int sys_error)
2003 {
2004 	struct T_error_ack	*teackp;
2005 
2006 	if ((mp = tpi_ack_alloc(mp, sizeof (struct T_error_ack),
2007 	    M_PCPROTO, T_ERROR_ACK)) != NULL) {
2008 		teackp = (struct T_error_ack *)mp->b_rptr;
2009 		teackp->ERROR_prim = primitive;
2010 		teackp->TLI_error = t_error;
2011 		teackp->UNIX_error = sys_error;
2012 		putnext(UDP_RD(q), mp);
2013 	}
2014 }
2015 
2016 /*ARGSUSED*/
2017 static int
2018 udp_extra_priv_ports_get(queue_t *q, mblk_t *mp, caddr_t cp, cred_t *cr)
2019 {
2020 	int i;
2021 
2022 	for (i = 0; i < udp_g_num_epriv_ports; i++) {
2023 		if (udp_g_epriv_ports[i] != 0)
2024 			(void) mi_mpprintf(mp, "%d ", udp_g_epriv_ports[i]);
2025 	}
2026 	return (0);
2027 }
2028 
2029 /* ARGSUSED */
2030 static int
2031 udp_extra_priv_ports_add(queue_t *q, mblk_t *mp, char *value, caddr_t cp,
2032     cred_t *cr)
2033 {
2034 	long	new_value;
2035 	int	i;
2036 
2037 	/*
2038 	 * Fail the request if the new value does not lie within the
2039 	 * port number limits.
2040 	 */
2041 	if (ddi_strtol(value, NULL, 10, &new_value) != 0 ||
2042 	    new_value <= 0 || new_value >= 65536) {
2043 		return (EINVAL);
2044 	}
2045 
2046 	/* Check if the value is already in the list */
2047 	for (i = 0; i < udp_g_num_epriv_ports; i++) {
2048 		if (new_value == udp_g_epriv_ports[i]) {
2049 			return (EEXIST);
2050 		}
2051 	}
2052 	/* Find an empty slot */
2053 	for (i = 0; i < udp_g_num_epriv_ports; i++) {
2054 		if (udp_g_epriv_ports[i] == 0)
2055 			break;
2056 	}
2057 	if (i == udp_g_num_epriv_ports) {
2058 		return (EOVERFLOW);
2059 	}
2060 
2061 	/* Set the new value */
2062 	udp_g_epriv_ports[i] = (in_port_t)new_value;
2063 	return (0);
2064 }
2065 
2066 /* ARGSUSED */
2067 static int
2068 udp_extra_priv_ports_del(queue_t *q, mblk_t *mp, char *value, caddr_t cp,
2069     cred_t *cr)
2070 {
2071 	long	new_value;
2072 	int	i;
2073 
2074 	/*
2075 	 * Fail the request if the new value does not lie within the
2076 	 * port number limits.
2077 	 */
2078 	if (ddi_strtol(value, NULL, 10, &new_value) != 0 ||
2079 	    new_value <= 0 || new_value >= 65536) {
2080 		return (EINVAL);
2081 	}
2082 
2083 	/* Check that the value is already in the list */
2084 	for (i = 0; i < udp_g_num_epriv_ports; i++) {
2085 		if (udp_g_epriv_ports[i] == new_value)
2086 			break;
2087 	}
2088 	if (i == udp_g_num_epriv_ports) {
2089 		return (ESRCH);
2090 	}
2091 
2092 	/* Clear the value */
2093 	udp_g_epriv_ports[i] = 0;
2094 	return (0);
2095 }
2096 
2097 /* At minimum we need 4 bytes of UDP header */
2098 #define	ICMP_MIN_UDP_HDR	4
2099 
2100 /*
2101  * udp_icmp_error is called by udp_rput to process ICMP msgs. passed up by IP.
2102  * Generates the appropriate T_UDERROR_IND for permanent (non-transient) errors.
2103  * Assumes that IP has pulled up everything up to and including the ICMP header.
2104  * An M_CTL could potentially come here from some other module (i.e. if UDP
2105  * is pushed on some module other than IP). Thus, if we find that the M_CTL
2106  * does not have enough ICMP information , following STREAMS conventions,
2107  * we send it upstream assuming it is an M_CTL we don't understand.
2108  */
2109 static void
2110 udp_icmp_error(queue_t *q, mblk_t *mp)
2111 {
2112 	icmph_t *icmph;
2113 	ipha_t	*ipha;
2114 	int	iph_hdr_length;
2115 	udpha_t	*udpha;
2116 	sin_t	sin;
2117 	sin6_t	sin6;
2118 	mblk_t	*mp1;
2119 	int	error = 0;
2120 	size_t	mp_size = MBLKL(mp);
2121 	udp_t	*udp = Q_TO_UDP(q);
2122 
2123 	/*
2124 	 * Assume IP provides aligned packets - otherwise toss
2125 	 */
2126 	if (!OK_32PTR(mp->b_rptr)) {
2127 		freemsg(mp);
2128 		return;
2129 	}
2130 
2131 	/*
2132 	 * Verify that we have a complete IP header and the application has
2133 	 * asked for errors. If not, send it upstream.
2134 	 */
2135 	if (!udp->udp_dgram_errind || mp_size < sizeof (ipha_t)) {
2136 noticmpv4:
2137 		putnext(UDP_RD(q), mp);
2138 		return;
2139 	}
2140 
2141 	ipha = (ipha_t *)mp->b_rptr;
2142 	/*
2143 	 * Verify IP version. Anything other than IPv4 or IPv6 packet is sent
2144 	 * upstream. ICMPv6  is handled in udp_icmp_error_ipv6.
2145 	 */
2146 	switch (IPH_HDR_VERSION(ipha)) {
2147 	case IPV6_VERSION:
2148 		udp_icmp_error_ipv6(q, mp);
2149 		return;
2150 	case IPV4_VERSION:
2151 		break;
2152 	default:
2153 		goto noticmpv4;
2154 	}
2155 
2156 	/* Skip past the outer IP and ICMP headers */
2157 	iph_hdr_length = IPH_HDR_LENGTH(ipha);
2158 	icmph = (icmph_t *)&mp->b_rptr[iph_hdr_length];
2159 	/*
2160 	 * If we don't have the correct outer IP header length or if the ULP
2161 	 * is not IPPROTO_ICMP or if we don't have a complete inner IP header
2162 	 * send the packet upstream.
2163 	 */
2164 	if (iph_hdr_length < sizeof (ipha_t) ||
2165 	    ipha->ipha_protocol != IPPROTO_ICMP ||
2166 	    (ipha_t *)&icmph[1] + 1 > (ipha_t *)mp->b_wptr) {
2167 		goto noticmpv4;
2168 	}
2169 	ipha = (ipha_t *)&icmph[1];
2170 
2171 	/* Skip past the inner IP and find the ULP header */
2172 	iph_hdr_length = IPH_HDR_LENGTH(ipha);
2173 	udpha = (udpha_t *)((char *)ipha + iph_hdr_length);
2174 	/*
2175 	 * If we don't have the correct inner IP header length or if the ULP
2176 	 * is not IPPROTO_UDP or if we don't have at least ICMP_MIN_UDP_HDR
2177 	 * bytes of UDP header, send it upstream.
2178 	 */
2179 	if (iph_hdr_length < sizeof (ipha_t) ||
2180 	    ipha->ipha_protocol != IPPROTO_UDP ||
2181 	    (uchar_t *)udpha + ICMP_MIN_UDP_HDR > mp->b_wptr) {
2182 		goto noticmpv4;
2183 	}
2184 
2185 	switch (icmph->icmph_type) {
2186 	case ICMP_DEST_UNREACHABLE:
2187 		switch (icmph->icmph_code) {
2188 		case ICMP_FRAGMENTATION_NEEDED:
2189 			/*
2190 			 * IP has already adjusted the path MTU.
2191 			 * XXX Somehow pass MTU indication to application?
2192 			 */
2193 			break;
2194 		case ICMP_PORT_UNREACHABLE:
2195 		case ICMP_PROTOCOL_UNREACHABLE:
2196 			error = ECONNREFUSED;
2197 			break;
2198 		default:
2199 			/* Transient errors */
2200 			break;
2201 		}
2202 		break;
2203 	default:
2204 		/* Transient errors */
2205 		break;
2206 	}
2207 	if (error == 0) {
2208 		freemsg(mp);
2209 		return;
2210 	}
2211 
2212 	switch (udp->udp_family) {
2213 	case AF_INET:
2214 		sin = sin_null;
2215 		sin.sin_family = AF_INET;
2216 		sin.sin_addr.s_addr = ipha->ipha_dst;
2217 		sin.sin_port = udpha->uha_dst_port;
2218 		mp1 = mi_tpi_uderror_ind((char *)&sin, sizeof (sin_t), NULL, 0,
2219 		    error);
2220 		break;
2221 	case AF_INET6:
2222 		sin6 = sin6_null;
2223 		sin6.sin6_family = AF_INET6;
2224 		IN6_IPADDR_TO_V4MAPPED(ipha->ipha_dst, &sin6.sin6_addr);
2225 		sin6.sin6_port = udpha->uha_dst_port;
2226 
2227 		mp1 = mi_tpi_uderror_ind((char *)&sin6, sizeof (sin6_t),
2228 		    NULL, 0, error);
2229 		break;
2230 	}
2231 	if (mp1)
2232 		putnext(UDP_RD(q), mp1);
2233 	freemsg(mp);
2234 }
2235 
2236 /*
2237  * udp_icmp_error_ipv6 is called by udp_icmp_error to process ICMP for IPv6.
2238  * Generates the appropriate T_UDERROR_IND for permanent (non-transient) errors.
2239  * Assumes that IP has pulled up all the extension headers as well as the
2240  * ICMPv6 header.
2241  * An M_CTL could potentially come here from some other module (i.e. if UDP
2242  * is pushed on some module other than IP). Thus, if we find that the M_CTL
2243  * does not have enough ICMP information , following STREAMS conventions,
2244  * we send it upstream assuming it is an M_CTL we don't understand. The reason
2245  * it might get here is if the non-ICMP M_CTL accidently has 6 in the version
2246  * field (when cast to ipha_t in udp_icmp_error).
2247  */
2248 static void
2249 udp_icmp_error_ipv6(queue_t *q, mblk_t *mp)
2250 {
2251 	icmp6_t		*icmp6;
2252 	ip6_t		*ip6h, *outer_ip6h;
2253 	uint16_t	hdr_length;
2254 	uint8_t		*nexthdrp;
2255 	udpha_t		*udpha;
2256 	sin6_t		sin6;
2257 	mblk_t		*mp1;
2258 	int		error = 0;
2259 	size_t		mp_size = MBLKL(mp);
2260 	udp_t		*udp = Q_TO_UDP(q);
2261 
2262 	/*
2263 	 * Verify that we have a complete IP header. If not, send it upstream.
2264 	 */
2265 	if (mp_size < sizeof (ip6_t)) {
2266 noticmpv6:
2267 		putnext(UDP_RD(q), mp);
2268 		return;
2269 	}
2270 
2271 	outer_ip6h = (ip6_t *)mp->b_rptr;
2272 	/*
2273 	 * Verify this is an ICMPV6 packet, else send it upstream
2274 	 */
2275 	if (outer_ip6h->ip6_nxt == IPPROTO_ICMPV6) {
2276 		hdr_length = IPV6_HDR_LEN;
2277 	} else if (!ip_hdr_length_nexthdr_v6(mp, outer_ip6h, &hdr_length,
2278 	    &nexthdrp) ||
2279 	    *nexthdrp != IPPROTO_ICMPV6) {
2280 		goto noticmpv6;
2281 	}
2282 	icmp6 = (icmp6_t *)&mp->b_rptr[hdr_length];
2283 	ip6h = (ip6_t *)&icmp6[1];
2284 	/*
2285 	 * Verify we have a complete ICMP and inner IP header.
2286 	 */
2287 	if ((uchar_t *)&ip6h[1] > mp->b_wptr)
2288 		goto noticmpv6;
2289 
2290 	if (!ip_hdr_length_nexthdr_v6(mp, ip6h, &hdr_length, &nexthdrp))
2291 		goto noticmpv6;
2292 	udpha = (udpha_t *)((char *)ip6h + hdr_length);
2293 	/*
2294 	 * Validate inner header. If the ULP is not IPPROTO_UDP or if we don't
2295 	 * have at least ICMP_MIN_UDP_HDR bytes of  UDP header send the
2296 	 * packet upstream.
2297 	 */
2298 	if ((*nexthdrp != IPPROTO_UDP) ||
2299 	    ((uchar_t *)udpha + ICMP_MIN_UDP_HDR) > mp->b_wptr) {
2300 		goto noticmpv6;
2301 	}
2302 
2303 	switch (icmp6->icmp6_type) {
2304 	case ICMP6_DST_UNREACH:
2305 		switch (icmp6->icmp6_code) {
2306 		case ICMP6_DST_UNREACH_NOPORT:
2307 			error = ECONNREFUSED;
2308 			break;
2309 		case ICMP6_DST_UNREACH_ADMIN:
2310 		case ICMP6_DST_UNREACH_NOROUTE:
2311 		case ICMP6_DST_UNREACH_BEYONDSCOPE:
2312 		case ICMP6_DST_UNREACH_ADDR:
2313 			/* Transient errors */
2314 			break;
2315 		default:
2316 			break;
2317 		}
2318 		break;
2319 	case ICMP6_PACKET_TOO_BIG: {
2320 		struct T_unitdata_ind	*tudi;
2321 		struct T_opthdr		*toh;
2322 		size_t			udi_size;
2323 		mblk_t			*newmp;
2324 		t_scalar_t		opt_length = sizeof (struct T_opthdr) +
2325 		    sizeof (struct ip6_mtuinfo);
2326 		sin6_t			*sin6;
2327 		struct ip6_mtuinfo	*mtuinfo;
2328 
2329 		/*
2330 		 * If the application has requested to receive path mtu
2331 		 * information, send up an empty message containing an
2332 		 * IPV6_PATHMTU ancillary data item.
2333 		 */
2334 		if (!udp->udp_ipv6_recvpathmtu)
2335 			break;
2336 
2337 		udi_size = sizeof (struct T_unitdata_ind) + sizeof (sin6_t) +
2338 		    opt_length;
2339 		if ((newmp = allocb(udi_size, BPRI_MED)) == NULL) {
2340 			BUMP_MIB(&udp_mib, udpInErrors);
2341 			break;
2342 		}
2343 
2344 		/*
2345 		 * newmp->b_cont is left to NULL on purpose.  This is an
2346 		 * empty message containing only ancillary data.
2347 		 */
2348 		newmp->b_datap->db_type = M_PROTO;
2349 		tudi = (struct T_unitdata_ind *)newmp->b_rptr;
2350 		newmp->b_wptr = (uchar_t *)tudi + udi_size;
2351 		tudi->PRIM_type = T_UNITDATA_IND;
2352 		tudi->SRC_length = sizeof (sin6_t);
2353 		tudi->SRC_offset = sizeof (struct T_unitdata_ind);
2354 		tudi->OPT_offset = tudi->SRC_offset + sizeof (sin6_t);
2355 		tudi->OPT_length = opt_length;
2356 
2357 		sin6 = (sin6_t *)&tudi[1];
2358 		bzero(sin6, sizeof (sin6_t));
2359 		sin6->sin6_family = AF_INET6;
2360 		sin6->sin6_addr = udp->udp_v6dst;
2361 
2362 		toh = (struct T_opthdr *)&sin6[1];
2363 		toh->level = IPPROTO_IPV6;
2364 		toh->name = IPV6_PATHMTU;
2365 		toh->len = opt_length;
2366 		toh->status = 0;
2367 
2368 		mtuinfo = (struct ip6_mtuinfo *)&toh[1];
2369 		bzero(mtuinfo, sizeof (struct ip6_mtuinfo));
2370 		mtuinfo->ip6m_addr.sin6_family = AF_INET6;
2371 		mtuinfo->ip6m_addr.sin6_addr = ip6h->ip6_dst;
2372 		mtuinfo->ip6m_mtu = icmp6->icmp6_mtu;
2373 		/*
2374 		 * We've consumed everything we need from the original
2375 		 * message.  Free it, then send our empty message.
2376 		 */
2377 		freemsg(mp);
2378 		putnext(UDP_RD(q), newmp);
2379 		return;
2380 	}
2381 	case ICMP6_TIME_EXCEEDED:
2382 		/* Transient errors */
2383 		break;
2384 	case ICMP6_PARAM_PROB:
2385 		/* If this corresponds to an ICMP_PROTOCOL_UNREACHABLE */
2386 		if (icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER &&
2387 		    (uchar_t *)ip6h + icmp6->icmp6_pptr ==
2388 		    (uchar_t *)nexthdrp) {
2389 			error = ECONNREFUSED;
2390 			break;
2391 		}
2392 		break;
2393 	}
2394 	if (error == 0) {
2395 		freemsg(mp);
2396 		return;
2397 	}
2398 
2399 	sin6 = sin6_null;
2400 	sin6.sin6_family = AF_INET6;
2401 	sin6.sin6_addr = ip6h->ip6_dst;
2402 	sin6.sin6_port = udpha->uha_dst_port;
2403 	sin6.sin6_flowinfo = ip6h->ip6_vcf & ~IPV6_VERS_AND_FLOW_MASK;
2404 
2405 	mp1 = mi_tpi_uderror_ind((char *)&sin6, sizeof (sin6_t), NULL, 0,
2406 	    error);
2407 	if (mp1)
2408 		putnext(UDP_RD(q), mp1);
2409 	freemsg(mp);
2410 }
2411 
2412 /*
2413  * This routine responds to T_ADDR_REQ messages.  It is called by udp_wput.
2414  * The local address is filled in if endpoint is bound. The remote address
2415  * is filled in if remote address has been precified ("connected endpoint")
2416  * (The concept of connected CLTS sockets is alien to published TPI
2417  *  but we support it anyway).
2418  */
2419 static void
2420 udp_addr_req(queue_t *q, mblk_t *mp)
2421 {
2422 	sin_t	*sin;
2423 	sin6_t	*sin6;
2424 	mblk_t	*ackmp;
2425 	struct T_addr_ack *taa;
2426 	udp_t	*udp = Q_TO_UDP(q);
2427 
2428 	/* Make it large enough for worst case */
2429 	ackmp = reallocb(mp, sizeof (struct T_addr_ack) +
2430 	    2 * sizeof (sin6_t), 1);
2431 	if (ackmp == NULL) {
2432 		udp_err_ack(q, mp, TSYSERR, ENOMEM);
2433 		return;
2434 	}
2435 	taa = (struct T_addr_ack *)ackmp->b_rptr;
2436 
2437 	bzero(taa, sizeof (struct T_addr_ack));
2438 	ackmp->b_wptr = (uchar_t *)&taa[1];
2439 
2440 	taa->PRIM_type = T_ADDR_ACK;
2441 	ackmp->b_datap->db_type = M_PCPROTO;
2442 	/*
2443 	 * Note: Following code assumes 32 bit alignment of basic
2444 	 * data structures like sin_t and struct T_addr_ack.
2445 	 */
2446 	if (udp->udp_state != TS_UNBND) {
2447 		/*
2448 		 * Fill in local address first
2449 		 */
2450 		taa->LOCADDR_offset = sizeof (*taa);
2451 		if (udp->udp_family == AF_INET) {
2452 			taa->LOCADDR_length = sizeof (sin_t);
2453 			sin = (sin_t *)&taa[1];
2454 			/* Fill zeroes and then initialize non-zero fields */
2455 			*sin = sin_null;
2456 			sin->sin_family = AF_INET;
2457 			if (!IN6_IS_ADDR_V4MAPPED_ANY(&udp->udp_v6src) &&
2458 			    !IN6_IS_ADDR_UNSPECIFIED(&udp->udp_v6src)) {
2459 				IN6_V4MAPPED_TO_IPADDR(&udp->udp_v6src,
2460 				    sin->sin_addr.s_addr);
2461 			} else {
2462 				/*
2463 				 * INADDR_ANY
2464 				 * udp_v6src is not set, we might be bound to
2465 				 * broadcast/multicast. Use udp_bound_v6src as
2466 				 * local address instead (that could
2467 				 * also still be INADDR_ANY)
2468 				 */
2469 				IN6_V4MAPPED_TO_IPADDR(&udp->udp_bound_v6src,
2470 				    sin->sin_addr.s_addr);
2471 			}
2472 			sin->sin_port = udp->udp_port;
2473 			ackmp->b_wptr = (uchar_t *)&sin[1];
2474 			if (udp->udp_state == TS_DATA_XFER) {
2475 				/*
2476 				 * connected, fill remote address too
2477 				 */
2478 				taa->REMADDR_length = sizeof (sin_t);
2479 				/* assumed 32-bit alignment */
2480 				taa->REMADDR_offset = taa->LOCADDR_offset +
2481 				    taa->LOCADDR_length;
2482 
2483 				sin = (sin_t *)(ackmp->b_rptr +
2484 				    taa->REMADDR_offset);
2485 				/* initialize */
2486 				*sin = sin_null;
2487 				sin->sin_family = AF_INET;
2488 				sin->sin_addr.s_addr =
2489 				    V4_PART_OF_V6(udp->udp_v6dst);
2490 				sin->sin_port = udp->udp_dstport;
2491 				ackmp->b_wptr = (uchar_t *)&sin[1];
2492 			}
2493 		} else {
2494 			taa->LOCADDR_length = sizeof (sin6_t);
2495 			sin6 = (sin6_t *)&taa[1];
2496 			/* Fill zeroes and then initialize non-zero fields */
2497 			*sin6 = sin6_null;
2498 			sin6->sin6_family = AF_INET6;
2499 			if (!IN6_IS_ADDR_UNSPECIFIED(&udp->udp_v6src)) {
2500 				sin6->sin6_addr = udp->udp_v6src;
2501 			} else {
2502 				/*
2503 				 * UNSPECIFIED
2504 				 * udp_v6src is not set, we might be bound to
2505 				 * broadcast/multicast. Use udp_bound_v6src as
2506 				 * local address instead (that could
2507 				 * also still be UNSPECIFIED)
2508 				 */
2509 				sin6->sin6_addr =
2510 				    udp->udp_bound_v6src;
2511 			}
2512 			sin6->sin6_port = udp->udp_port;
2513 			ackmp->b_wptr = (uchar_t *)&sin6[1];
2514 			if (udp->udp_state == TS_DATA_XFER) {
2515 				/*
2516 				 * connected, fill remote address too
2517 				 */
2518 				taa->REMADDR_length = sizeof (sin6_t);
2519 				/* assumed 32-bit alignment */
2520 				taa->REMADDR_offset = taa->LOCADDR_offset +
2521 				    taa->LOCADDR_length;
2522 
2523 				sin6 = (sin6_t *)(ackmp->b_rptr +
2524 				    taa->REMADDR_offset);
2525 				/* initialize */
2526 				*sin6 = sin6_null;
2527 				sin6->sin6_family = AF_INET6;
2528 				sin6->sin6_addr = udp->udp_v6dst;
2529 				sin6->sin6_port =  udp->udp_dstport;
2530 				ackmp->b_wptr = (uchar_t *)&sin6[1];
2531 			}
2532 			ackmp->b_wptr = (uchar_t *)&sin6[1];
2533 		}
2534 	}
2535 	ASSERT(ackmp->b_wptr <= ackmp->b_datap->db_lim);
2536 	putnext(UDP_RD(q), ackmp);
2537 }
2538 
2539 static void
2540 udp_copy_info(struct T_info_ack *tap, udp_t *udp)
2541 {
2542 	if (udp->udp_family == AF_INET) {
2543 		*tap = udp_g_t_info_ack_ipv4;
2544 	} else {
2545 		*tap = udp_g_t_info_ack_ipv6;
2546 	}
2547 	tap->CURRENT_state = udp->udp_state;
2548 	tap->OPT_size = udp_max_optsize;
2549 }
2550 
2551 /*
2552  * This routine responds to T_CAPABILITY_REQ messages.  It is called by
2553  * udp_wput.  Much of the T_CAPABILITY_ACK information is copied from
2554  * udp_g_t_info_ack.  The current state of the stream is copied from
2555  * udp_state.
2556  */
2557 static void
2558 udp_capability_req(queue_t *q, mblk_t *mp)
2559 {
2560 	t_uscalar_t		cap_bits1;
2561 	struct T_capability_ack	*tcap;
2562 	udp_t	*udp = Q_TO_UDP(q);
2563 
2564 	cap_bits1 = ((struct T_capability_req *)mp->b_rptr)->CAP_bits1;
2565 
2566 	mp = tpi_ack_alloc(mp, sizeof (struct T_capability_ack),
2567 	    mp->b_datap->db_type, T_CAPABILITY_ACK);
2568 	if (!mp)
2569 		return;
2570 
2571 	tcap = (struct T_capability_ack *)mp->b_rptr;
2572 	tcap->CAP_bits1 = 0;
2573 
2574 	if (cap_bits1 & TC1_INFO) {
2575 		udp_copy_info(&tcap->INFO_ack, udp);
2576 		tcap->CAP_bits1 |= TC1_INFO;
2577 	}
2578 
2579 	putnext(UDP_RD(q), mp);
2580 }
2581 
2582 /*
2583  * This routine responds to T_INFO_REQ messages.  It is called by udp_wput.
2584  * Most of the T_INFO_ACK information is copied from udp_g_t_info_ack.
2585  * The current state of the stream is copied from udp_state.
2586  */
2587 static void
2588 udp_info_req(queue_t *q, mblk_t *mp)
2589 {
2590 	udp_t *udp = Q_TO_UDP(q);
2591 
2592 	/* Create a T_INFO_ACK message. */
2593 	mp = tpi_ack_alloc(mp, sizeof (struct T_info_ack), M_PCPROTO,
2594 	    T_INFO_ACK);
2595 	if (!mp)
2596 		return;
2597 	udp_copy_info((struct T_info_ack *)mp->b_rptr, udp);
2598 	putnext(UDP_RD(q), mp);
2599 }
2600 
2601 /*
2602  * IP recognizes seven kinds of bind requests:
2603  *
2604  * - A zero-length address binds only to the protocol number.
2605  *
2606  * - A 4-byte address is treated as a request to
2607  * validate that the address is a valid local IPv4
2608  * address, appropriate for an application to bind to.
2609  * IP does the verification, but does not make any note
2610  * of the address at this time.
2611  *
2612  * - A 16-byte address contains is treated as a request
2613  * to validate a local IPv6 address, as the 4-byte
2614  * address case above.
2615  *
2616  * - A 16-byte sockaddr_in to validate the local IPv4 address and also
2617  * use it for the inbound fanout of packets.
2618  *
2619  * - A 24-byte sockaddr_in6 to validate the local IPv6 address and also
2620  * use it for the inbound fanout of packets.
2621  *
2622  * - A 12-byte address (ipa_conn_t) containing complete IPv4 fanout
2623  * information consisting of local and remote addresses
2624  * and ports.  In this case, the addresses are both
2625  * validated as appropriate for this operation, and, if
2626  * so, the information is retained for use in the
2627  * inbound fanout.
2628  *
2629  * - A 36-byte address address (ipa6_conn_t) containing complete IPv6
2630  * fanout information, like the 12-byte case above.
2631  *
2632  * IP will also fill in the IRE request mblk with information
2633  * regarding our peer.  In all cases, we notify IP of our protocol
2634  * type by appending a single protocol byte to the bind request.
2635  */
2636 static mblk_t *
2637 udp_ip_bind_mp(udp_t *udp, t_scalar_t bind_prim, t_scalar_t addr_length)
2638 {
2639 	char	*cp;
2640 	mblk_t	*mp;
2641 	struct T_bind_req *tbr;
2642 	ipa_conn_t	*ac;
2643 	ipa6_conn_t	*ac6;
2644 	sin_t		*sin;
2645 	sin6_t		*sin6;
2646 
2647 	ASSERT(bind_prim == O_T_BIND_REQ || bind_prim == T_BIND_REQ);
2648 
2649 	mp = allocb(sizeof (*tbr) + addr_length + 1, BPRI_HI);
2650 	if (!mp)
2651 		return (mp);
2652 	mp->b_datap->db_type = M_PROTO;
2653 	tbr = (struct T_bind_req *)mp->b_rptr;
2654 	tbr->PRIM_type = bind_prim;
2655 	tbr->ADDR_offset = sizeof (*tbr);
2656 	tbr->CONIND_number = 0;
2657 	tbr->ADDR_length = addr_length;
2658 	cp = (char *)&tbr[1];
2659 	switch (addr_length) {
2660 	case sizeof (ipa_conn_t):
2661 		ASSERT(udp->udp_family == AF_INET);
2662 		/* Append a request for an IRE */
2663 		mp->b_cont = allocb(sizeof (ire_t), BPRI_HI);
2664 		if (!mp->b_cont) {
2665 			freemsg(mp);
2666 			return (NULL);
2667 		}
2668 		mp->b_cont->b_wptr += sizeof (ire_t);
2669 		mp->b_cont->b_datap->db_type = IRE_DB_REQ_TYPE;
2670 
2671 		/* cp known to be 32 bit aligned */
2672 		ac = (ipa_conn_t *)cp;
2673 		ac->ac_laddr = V4_PART_OF_V6(udp->udp_v6src);
2674 		ac->ac_faddr = V4_PART_OF_V6(udp->udp_v6dst);
2675 		ac->ac_fport = udp->udp_dstport;
2676 		ac->ac_lport = udp->udp_port;
2677 		break;
2678 
2679 	case sizeof (ipa6_conn_t):
2680 		ASSERT(udp->udp_family == AF_INET6);
2681 		/* Append a request for an IRE */
2682 		mp->b_cont = allocb(sizeof (ire_t), BPRI_HI);
2683 		if (!mp->b_cont) {
2684 			freemsg(mp);
2685 			return (NULL);
2686 		}
2687 		mp->b_cont->b_wptr += sizeof (ire_t);
2688 		mp->b_cont->b_datap->db_type = IRE_DB_REQ_TYPE;
2689 
2690 		/* cp known to be 32 bit aligned */
2691 		ac6 = (ipa6_conn_t *)cp;
2692 		ac6->ac6_laddr = udp->udp_v6src;
2693 		ac6->ac6_faddr = udp->udp_v6dst;
2694 		ac6->ac6_fport = udp->udp_dstport;
2695 		ac6->ac6_lport = udp->udp_port;
2696 		break;
2697 
2698 	case sizeof (sin_t):
2699 		ASSERT(udp->udp_family == AF_INET);
2700 		/* Append a request for an IRE */
2701 		mp->b_cont = allocb(sizeof (ire_t), BPRI_HI);
2702 		if (!mp->b_cont) {
2703 			freemsg(mp);
2704 			return (NULL);
2705 		}
2706 		mp->b_cont->b_wptr += sizeof (ire_t);
2707 		mp->b_cont->b_datap->db_type = IRE_DB_REQ_TYPE;
2708 
2709 		sin = (sin_t *)cp;
2710 		*sin = sin_null;
2711 		sin->sin_family = AF_INET;
2712 		sin->sin_addr.s_addr = V4_PART_OF_V6(udp->udp_bound_v6src);
2713 		sin->sin_port = udp->udp_port;
2714 		break;
2715 
2716 	case sizeof (sin6_t):
2717 		ASSERT(udp->udp_family == AF_INET6);
2718 		/* Append a request for an IRE */
2719 		mp->b_cont = allocb(sizeof (ire_t), BPRI_HI);
2720 		if (!mp->b_cont) {
2721 			freemsg(mp);
2722 			return (NULL);
2723 		}
2724 		mp->b_cont->b_wptr += sizeof (ire_t);
2725 		mp->b_cont->b_datap->db_type = IRE_DB_REQ_TYPE;
2726 
2727 		sin6 = (sin6_t *)cp;
2728 		*sin6 = sin6_null;
2729 		sin6->sin6_family = AF_INET6;
2730 		sin6->sin6_addr = udp->udp_bound_v6src;
2731 		sin6->sin6_port = udp->udp_port;
2732 		break;
2733 	}
2734 	/* Add protocol number to end */
2735 	cp[addr_length] = (char)IPPROTO_UDP;
2736 	mp->b_wptr = (uchar_t *)&cp[addr_length + 1];
2737 	return (mp);
2738 }
2739 
2740 /*
2741  * This is the open routine for udp.  It allocates a udp_t structure for
2742  * the stream and, on the first open of the module, creates an ND table.
2743  */
2744 /* ARGSUSED */
2745 static int
2746 udp_open(queue_t *q, dev_t *devp, int flag, int sflag, cred_t *credp)
2747 {
2748 	int	err;
2749 	udp_t	*udp;
2750 	conn_t *connp;
2751 	zoneid_t zoneid = getzoneid();
2752 	queue_t	*ip_wq;
2753 	char	*name;
2754 
2755 	TRACE_1(TR_FAC_UDP, TR_UDP_OPEN, "udp_open: q %p", q);
2756 
2757 	/* If the stream is already open, return immediately. */
2758 	if (q->q_ptr != NULL)
2759 		return (0);
2760 
2761 	/* If this is not a push of udp as a module, fail. */
2762 	if (sflag != MODOPEN)
2763 		return (EINVAL);
2764 
2765 	q->q_hiwat = udp_recv_hiwat;
2766 	WR(q)->q_hiwat = udp_xmit_hiwat;
2767 	WR(q)->q_lowat = udp_xmit_lowat;
2768 
2769 	/* Insert ourselves in the stream since we're about to walk q_next */
2770 	qprocson(q);
2771 
2772 	udp = kmem_cache_alloc(udp_cache, KM_SLEEP);
2773 	bzero(udp, sizeof (*udp));
2774 
2775 	/*
2776 	 * UDP is supported only as a module and it has to be pushed directly
2777 	 * above the device instance of IP. If UDP is pushed anywhere else
2778 	 * on a stream, it will support just T_SVR4_OPTMGMT_REQ for the
2779 	 * sake of MIB browsers and fail everything else.
2780 	 */
2781 	ip_wq = WR(q)->q_next;
2782 	if (ip_wq->q_next != NULL ||
2783 	    (name = ip_wq->q_qinfo->qi_minfo->mi_idname) == NULL ||
2784 	    strcmp(name, IP_MOD_NAME) != 0 ||
2785 	    ip_wq->q_qinfo->qi_minfo->mi_idnum != IP_MOD_ID) {
2786 		/* Support just SNMP for MIB browsers */
2787 		connp = ipcl_conn_create(IPCL_IPCCONN, KM_SLEEP);
2788 		connp->conn_rq = q;
2789 		connp->conn_wq = WR(q);
2790 		connp->conn_flags |= IPCL_UDPMOD;
2791 		connp->conn_cred = credp;
2792 		connp->conn_zoneid = zoneid;
2793 		connp->conn_udp = udp;
2794 		udp->udp_connp = connp;
2795 		q->q_ptr = WR(q)->q_ptr = connp;
2796 		crhold(credp);
2797 		q->q_qinfo = &udp_snmp_rinit;
2798 		WR(q)->q_qinfo = &udp_snmp_winit;
2799 		return (0);
2800 	}
2801 
2802 	/*
2803 	 * Initialize the udp_t structure for this stream.
2804 	 */
2805 	q = RD(ip_wq);
2806 	connp = Q_TO_CONN(q);
2807 	mutex_enter(&connp->conn_lock);
2808 	connp->conn_proto = IPPROTO_UDP;
2809 	connp->conn_flags |= IPCL_UDP;
2810 	connp->conn_sqp = IP_SQUEUE_GET(lbolt);
2811 	connp->conn_udp = udp;
2812 
2813 	/* Set the initial state of the stream and the privilege status. */
2814 	udp->udp_connp = connp;
2815 	udp->udp_state = TS_UNBND;
2816 	udp->udp_mode = UDP_MT_HOT;
2817 	if (getmajor(*devp) == (major_t)UDP6_MAJ) {
2818 		udp->udp_family = AF_INET6;
2819 		udp->udp_ipversion = IPV6_VERSION;
2820 		udp->udp_max_hdr_len = IPV6_HDR_LEN + UDPH_SIZE;
2821 		udp->udp_ttl = udp_ipv6_hoplimit;
2822 		connp->conn_af_isv6 = B_TRUE;
2823 		connp->conn_flags |= IPCL_ISV6;
2824 	} else {
2825 		udp->udp_family = AF_INET;
2826 		udp->udp_ipversion = IPV4_VERSION;
2827 		udp->udp_max_hdr_len = IP_SIMPLE_HDR_LENGTH + UDPH_SIZE;
2828 		udp->udp_ttl = udp_ipv4_ttl;
2829 		connp->conn_af_isv6 = B_FALSE;
2830 		connp->conn_flags &= ~IPCL_ISV6;
2831 	}
2832 
2833 	udp->udp_multicast_ttl = IP_DEFAULT_MULTICAST_TTL;
2834 	connp->conn_multicast_loop = IP_DEFAULT_MULTICAST_LOOP;
2835 	connp->conn_zoneid = zoneid;
2836 
2837 	if (connp->conn_flags & IPCL_SOCKET) {
2838 		udp->udp_issocket = B_TRUE;
2839 		udp->udp_direct_sockfs = B_TRUE;
2840 	}
2841 	mutex_exit(&connp->conn_lock);
2842 
2843 	/*
2844 	 * The transmit hiwat/lowat is only looked at on IP's queue.
2845 	 * Store in q_hiwat in order to return on SO_SNDBUF/SO_RCVBUF
2846 	 * getsockopts.
2847 	 */
2848 	q->q_hiwat = udp_recv_hiwat;
2849 	WR(q)->q_hiwat = udp_xmit_hiwat;
2850 	WR(q)->q_lowat = udp_xmit_lowat;
2851 
2852 	if (udp->udp_family == AF_INET6) {
2853 		/* Build initial header template for transmit */
2854 		if ((err = udp_build_hdrs(q, udp)) != 0) {
2855 			qprocsoff(UDP_RD(q));
2856 			udp->udp_connp = NULL;
2857 			connp->conn_udp = NULL;
2858 			kmem_cache_free(udp_cache, udp);
2859 			return (err);
2860 		}
2861 	}
2862 
2863 	/* Set the Stream head write offset and high watermark. */
2864 	(void) mi_set_sth_wroff(UDP_RD(q),
2865 	    udp->udp_max_hdr_len + udp_wroff_extra);
2866 	(void) mi_set_sth_hiwat(UDP_RD(q), udp_set_rcv_hiwat(udp, q->q_hiwat));
2867 
2868 	WR(UDP_RD(q))->q_qinfo = &udp_winit;
2869 
2870 	return (0);
2871 }
2872 
2873 /*
2874  * Which UDP options OK to set through T_UNITDATA_REQ...
2875  */
2876 /* ARGSUSED */
2877 static boolean_t
2878 udp_opt_allow_udr_set(t_scalar_t level, t_scalar_t name)
2879 {
2880 	return (B_TRUE);
2881 }
2882 
2883 /*
2884  * This routine gets default values of certain options whose default
2885  * values are maintained by protcol specific code
2886  */
2887 /* ARGSUSED */
2888 int
2889 udp_opt_default(queue_t	*q, t_scalar_t level, t_scalar_t name, uchar_t *ptr)
2890 {
2891 	int *i1 = (int *)ptr;
2892 
2893 	switch (level) {
2894 	case IPPROTO_IP:
2895 		switch (name) {
2896 		case IP_MULTICAST_TTL:
2897 			*ptr = (uchar_t)IP_DEFAULT_MULTICAST_TTL;
2898 			return (sizeof (uchar_t));
2899 		case IP_MULTICAST_LOOP:
2900 			*ptr = (uchar_t)IP_DEFAULT_MULTICAST_LOOP;
2901 			return (sizeof (uchar_t));
2902 		}
2903 		break;
2904 	case IPPROTO_IPV6:
2905 		switch (name) {
2906 		case IPV6_MULTICAST_HOPS:
2907 			*i1 = IP_DEFAULT_MULTICAST_TTL;
2908 			return (sizeof (int));
2909 		case IPV6_MULTICAST_LOOP:
2910 			*i1 = IP_DEFAULT_MULTICAST_LOOP;
2911 			return (sizeof (int));
2912 		case IPV6_UNICAST_HOPS:
2913 			*i1 = udp_ipv6_hoplimit;
2914 			return (sizeof (int));
2915 		}
2916 		break;
2917 	}
2918 	return (-1);
2919 }
2920 
2921 /*
2922  * This routine retrieves the current status of socket options
2923  * and expects the caller to pass in the queue pointer of the
2924  * upper instance.  It returns the size of the option retrieved.
2925  */
2926 int
2927 udp_opt_get(queue_t *q, t_scalar_t level, t_scalar_t name, uchar_t *ptr)
2928 {
2929 	int	*i1 = (int *)ptr;
2930 	conn_t	*connp;
2931 	udp_t	*udp;
2932 	ip6_pkt_t *ipp;
2933 
2934 	q = UDP_WR(q);
2935 	connp = Q_TO_CONN(q);
2936 	udp = connp->conn_udp;
2937 	ipp = &udp->udp_sticky_ipp;
2938 
2939 	switch (level) {
2940 	case SOL_SOCKET:
2941 		switch (name) {
2942 		case SO_DEBUG:
2943 			*i1 = udp->udp_debug;
2944 			break;	/* goto sizeof (int) option return */
2945 		case SO_REUSEADDR:
2946 			*i1 = udp->udp_reuseaddr;
2947 			break;	/* goto sizeof (int) option return */
2948 		case SO_TYPE:
2949 			*i1 = SOCK_DGRAM;
2950 			break;	/* goto sizeof (int) option return */
2951 
2952 		/*
2953 		 * The following three items are available here,
2954 		 * but are only meaningful to IP.
2955 		 */
2956 		case SO_DONTROUTE:
2957 			*i1 = udp->udp_dontroute;
2958 			break;	/* goto sizeof (int) option return */
2959 		case SO_USELOOPBACK:
2960 			*i1 = udp->udp_useloopback;
2961 			break;	/* goto sizeof (int) option return */
2962 		case SO_BROADCAST:
2963 			*i1 = udp->udp_broadcast;
2964 			break;	/* goto sizeof (int) option return */
2965 
2966 		case SO_SNDBUF:
2967 			*i1 = q->q_hiwat;
2968 			break;	/* goto sizeof (int) option return */
2969 		case SO_RCVBUF:
2970 			*i1 = RD(q)->q_hiwat;
2971 			break;	/* goto sizeof (int) option return */
2972 		case SO_DGRAM_ERRIND:
2973 			*i1 = udp->udp_dgram_errind;
2974 			break;	/* goto sizeof (int) option return */
2975 		case SO_RECVUCRED:
2976 			*i1 = udp->udp_recvucred;
2977 			break;	/* goto sizeof (int) option return */
2978 		default:
2979 			return (-1);
2980 		}
2981 		break;
2982 	case IPPROTO_IP:
2983 		if (udp->udp_family != AF_INET)
2984 			return (-1);
2985 		switch (name) {
2986 		case IP_OPTIONS:
2987 		case T_IP_OPTIONS:
2988 			if (udp->udp_ip_rcv_options_len)
2989 				bcopy(udp->udp_ip_rcv_options, ptr,
2990 				    udp->udp_ip_rcv_options_len);
2991 			return (udp->udp_ip_rcv_options_len);
2992 		case IP_TOS:
2993 		case T_IP_TOS:
2994 			*i1 = (int)udp->udp_type_of_service;
2995 			break;	/* goto sizeof (int) option return */
2996 		case IP_TTL:
2997 			*i1 = (int)udp->udp_ttl;
2998 			break;	/* goto sizeof (int) option return */
2999 		case IP_NEXTHOP:
3000 			/* Handled at IP level */
3001 			return (-EINVAL);
3002 		case IP_MULTICAST_IF:
3003 			/* 0 address if not set */
3004 			*(ipaddr_t *)ptr = udp->udp_multicast_if_addr;
3005 			return (sizeof (ipaddr_t));
3006 		case IP_MULTICAST_TTL:
3007 			*(uchar_t *)ptr = udp->udp_multicast_ttl;
3008 			return (sizeof (uchar_t));
3009 		case IP_MULTICAST_LOOP:
3010 			*ptr = connp->conn_multicast_loop;
3011 			return (sizeof (uint8_t));
3012 		case IP_RECVOPTS:
3013 			*i1 = udp->udp_recvopts;
3014 			break;	/* goto sizeof (int) option return */
3015 		case IP_RECVDSTADDR:
3016 			*i1 = udp->udp_recvdstaddr;
3017 			break;	/* goto sizeof (int) option return */
3018 		case IP_RECVIF:
3019 			*i1 = udp->udp_recvif;
3020 			break;	/* goto sizeof (int) option return */
3021 		case IP_RECVSLLA:
3022 			*i1 = udp->udp_recvslla;
3023 			break;	/* goto sizeof (int) option return */
3024 		case IP_RECVTTL:
3025 			*i1 = udp->udp_recvttl;
3026 			break;	/* goto sizeof (int) option return */
3027 		case IP_ADD_MEMBERSHIP:
3028 		case IP_DROP_MEMBERSHIP:
3029 		case IP_BLOCK_SOURCE:
3030 		case IP_UNBLOCK_SOURCE:
3031 		case IP_ADD_SOURCE_MEMBERSHIP:
3032 		case IP_DROP_SOURCE_MEMBERSHIP:
3033 		case MCAST_JOIN_GROUP:
3034 		case MCAST_LEAVE_GROUP:
3035 		case MCAST_BLOCK_SOURCE:
3036 		case MCAST_UNBLOCK_SOURCE:
3037 		case MCAST_JOIN_SOURCE_GROUP:
3038 		case MCAST_LEAVE_SOURCE_GROUP:
3039 		case IP_DONTFAILOVER_IF:
3040 			/* cannot "get" the value for these */
3041 			return (-1);
3042 		case IP_BOUND_IF:
3043 			/* Zero if not set */
3044 			*i1 = udp->udp_bound_if;
3045 			break;	/* goto sizeof (int) option return */
3046 		case IP_UNSPEC_SRC:
3047 			*i1 = udp->udp_unspec_source;
3048 			break;	/* goto sizeof (int) option return */
3049 		case IP_XMIT_IF:
3050 			*i1 = udp->udp_xmit_if;
3051 			break; /* goto sizeof (int) option return */
3052 		default:
3053 			return (-1);
3054 		}
3055 		break;
3056 	case IPPROTO_IPV6:
3057 		if (udp->udp_family != AF_INET6)
3058 			return (-1);
3059 		switch (name) {
3060 		case IPV6_UNICAST_HOPS:
3061 			*i1 = (unsigned int)udp->udp_ttl;
3062 			break;	/* goto sizeof (int) option return */
3063 		case IPV6_MULTICAST_IF:
3064 			/* 0 index if not set */
3065 			*i1 = udp->udp_multicast_if_index;
3066 			break;	/* goto sizeof (int) option return */
3067 		case IPV6_MULTICAST_HOPS:
3068 			*i1 = udp->udp_multicast_ttl;
3069 			break;	/* goto sizeof (int) option return */
3070 		case IPV6_MULTICAST_LOOP:
3071 			*i1 = connp->conn_multicast_loop;
3072 			break;	/* goto sizeof (int) option return */
3073 		case IPV6_JOIN_GROUP:
3074 		case IPV6_LEAVE_GROUP:
3075 		case MCAST_JOIN_GROUP:
3076 		case MCAST_LEAVE_GROUP:
3077 		case MCAST_BLOCK_SOURCE:
3078 		case MCAST_UNBLOCK_SOURCE:
3079 		case MCAST_JOIN_SOURCE_GROUP:
3080 		case MCAST_LEAVE_SOURCE_GROUP:
3081 			/* cannot "get" the value for these */
3082 			return (-1);
3083 		case IPV6_BOUND_IF:
3084 			/* Zero if not set */
3085 			*i1 = udp->udp_bound_if;
3086 			break;	/* goto sizeof (int) option return */
3087 		case IPV6_UNSPEC_SRC:
3088 			*i1 = udp->udp_unspec_source;
3089 			break;	/* goto sizeof (int) option return */
3090 		case IPV6_RECVPKTINFO:
3091 			*i1 = udp->udp_ipv6_recvpktinfo;
3092 			break;	/* goto sizeof (int) option return */
3093 		case IPV6_RECVTCLASS:
3094 			*i1 = udp->udp_ipv6_recvtclass;
3095 			break;	/* goto sizeof (int) option return */
3096 		case IPV6_RECVPATHMTU:
3097 			*i1 = udp->udp_ipv6_recvpathmtu;
3098 			break;	/* goto sizeof (int) option return */
3099 		case IPV6_RECVHOPLIMIT:
3100 			*i1 = udp->udp_ipv6_recvhoplimit;
3101 			break;	/* goto sizeof (int) option return */
3102 		case IPV6_RECVHOPOPTS:
3103 			*i1 = udp->udp_ipv6_recvhopopts;
3104 			break;	/* goto sizeof (int) option return */
3105 		case IPV6_RECVDSTOPTS:
3106 			*i1 = udp->udp_ipv6_recvdstopts;
3107 			break;	/* goto sizeof (int) option return */
3108 		case _OLD_IPV6_RECVDSTOPTS:
3109 			*i1 = udp->udp_old_ipv6_recvdstopts;
3110 			break;	/* goto sizeof (int) option return */
3111 		case IPV6_RECVRTHDRDSTOPTS:
3112 			*i1 = udp->udp_ipv6_recvrthdrdstopts;
3113 			break;	/* goto sizeof (int) option return */
3114 		case IPV6_RECVRTHDR:
3115 			*i1 = udp->udp_ipv6_recvrthdr;
3116 			break;	/* goto sizeof (int) option return */
3117 		case IPV6_PKTINFO: {
3118 			/* XXX assumes that caller has room for max size! */
3119 			struct in6_pktinfo *pkti;
3120 
3121 			pkti = (struct in6_pktinfo *)ptr;
3122 			if (ipp->ipp_fields & IPPF_IFINDEX)
3123 				pkti->ipi6_ifindex = ipp->ipp_ifindex;
3124 			else
3125 				pkti->ipi6_ifindex = 0;
3126 			if (ipp->ipp_fields & IPPF_ADDR)
3127 				pkti->ipi6_addr = ipp->ipp_addr;
3128 			else
3129 				pkti->ipi6_addr = ipv6_all_zeros;
3130 			return (sizeof (struct in6_pktinfo));
3131 		}
3132 		case IPV6_TCLASS:
3133 			if (ipp->ipp_fields & IPPF_TCLASS)
3134 				*i1 = ipp->ipp_tclass;
3135 			else
3136 				*i1 = IPV6_FLOW_TCLASS(
3137 				    IPV6_DEFAULT_VERS_AND_FLOW);
3138 			break;	/* goto sizeof (int) option return */
3139 		case IPV6_NEXTHOP: {
3140 			sin6_t *sin6 = (sin6_t *)ptr;
3141 
3142 			if (!(ipp->ipp_fields & IPPF_NEXTHOP))
3143 				return (0);
3144 			*sin6 = sin6_null;
3145 			sin6->sin6_family = AF_INET6;
3146 			sin6->sin6_addr = ipp->ipp_nexthop;
3147 			return (sizeof (sin6_t));
3148 		}
3149 		case IPV6_HOPOPTS:
3150 			if (!(ipp->ipp_fields & IPPF_HOPOPTS))
3151 				return (0);
3152 			bcopy(ipp->ipp_hopopts, ptr, ipp->ipp_hopoptslen);
3153 			return (ipp->ipp_hopoptslen);
3154 		case IPV6_RTHDRDSTOPTS:
3155 			if (!(ipp->ipp_fields & IPPF_RTDSTOPTS))
3156 				return (0);
3157 			bcopy(ipp->ipp_rtdstopts, ptr, ipp->ipp_rtdstoptslen);
3158 			return (ipp->ipp_rtdstoptslen);
3159 		case IPV6_RTHDR:
3160 			if (!(ipp->ipp_fields & IPPF_RTHDR))
3161 				return (0);
3162 			bcopy(ipp->ipp_rthdr, ptr, ipp->ipp_rthdrlen);
3163 			return (ipp->ipp_rthdrlen);
3164 		case IPV6_DSTOPTS:
3165 			if (!(ipp->ipp_fields & IPPF_DSTOPTS))
3166 				return (0);
3167 			bcopy(ipp->ipp_dstopts, ptr, ipp->ipp_dstoptslen);
3168 			return (ipp->ipp_dstoptslen);
3169 		case IPV6_PATHMTU:
3170 			return (ip_fill_mtuinfo(&udp->udp_v6dst,
3171 				udp->udp_dstport, (struct ip6_mtuinfo *)ptr));
3172 		default:
3173 			return (-1);
3174 		}
3175 		break;
3176 	case IPPROTO_UDP:
3177 		switch (name) {
3178 		case UDP_ANONPRIVBIND:
3179 			*i1 = udp->udp_anon_priv_bind;
3180 			break;
3181 		case UDP_EXCLBIND:
3182 			*i1 = udp->udp_exclbind ? UDP_EXCLBIND : 0;
3183 			break;
3184 		case UDP_RCVHDR:
3185 			*i1 = udp->udp_rcvhdr ? 1 : 0;
3186 			break;
3187 		default:
3188 			return (-1);
3189 		}
3190 		break;
3191 	default:
3192 		return (-1);
3193 	}
3194 	return (sizeof (int));
3195 }
3196 
3197 /*
3198  * This routine sets socket options; it expects the caller
3199  * to pass in the queue pointer of the upper instance.
3200  */
3201 /* ARGSUSED */
3202 int
3203 udp_opt_set(queue_t *q, uint_t optset_context, int level,
3204     int name, uint_t inlen, uchar_t *invalp, uint_t *outlenp,
3205     uchar_t *outvalp, void *thisdg_attrs, cred_t *cr, mblk_t *mblk)
3206 {
3207 	int	*i1 = (int *)invalp;
3208 	boolean_t onoff = (*i1 == 0) ? 0 : 1;
3209 	boolean_t checkonly;
3210 	int	error;
3211 	conn_t	*connp;
3212 	udp_t	*udp;
3213 
3214 	q = UDP_WR(q);
3215 	connp = Q_TO_CONN(q);
3216 	udp = connp->conn_udp;
3217 
3218 	switch (optset_context) {
3219 	case SETFN_OPTCOM_CHECKONLY:
3220 		checkonly = B_TRUE;
3221 		/*
3222 		 * Note: Implies T_CHECK semantics for T_OPTCOM_REQ
3223 		 * inlen != 0 implies value supplied and
3224 		 * 	we have to "pretend" to set it.
3225 		 * inlen == 0 implies that there is no
3226 		 * 	value part in T_CHECK request and just validation
3227 		 * done elsewhere should be enough, we just return here.
3228 		 */
3229 		if (inlen == 0) {
3230 			*outlenp = 0;
3231 			return (0);
3232 		}
3233 		break;
3234 	case SETFN_OPTCOM_NEGOTIATE:
3235 		checkonly = B_FALSE;
3236 		break;
3237 	case SETFN_UD_NEGOTIATE:
3238 	case SETFN_CONN_NEGOTIATE:
3239 		checkonly = B_FALSE;
3240 		/*
3241 		 * Negotiating local and "association-related" options
3242 		 * through T_UNITDATA_REQ.
3243 		 *
3244 		 * Following routine can filter out ones we do not
3245 		 * want to be "set" this way.
3246 		 */
3247 		if (!udp_opt_allow_udr_set(level, name)) {
3248 			*outlenp = 0;
3249 			return (EINVAL);
3250 		}
3251 		break;
3252 	default:
3253 		/*
3254 		 * We should never get here
3255 		 */
3256 		*outlenp = 0;
3257 		return (EINVAL);
3258 	}
3259 
3260 	ASSERT((optset_context != SETFN_OPTCOM_CHECKONLY) ||
3261 	    (optset_context == SETFN_OPTCOM_CHECKONLY && inlen != 0));
3262 
3263 	/*
3264 	 * For fixed length options, no sanity check
3265 	 * of passed in length is done. It is assumed *_optcom_req()
3266 	 * routines do the right thing.
3267 	 */
3268 
3269 	switch (level) {
3270 	case SOL_SOCKET:
3271 		switch (name) {
3272 		case SO_REUSEADDR:
3273 			if (!checkonly)
3274 				udp->udp_reuseaddr = onoff;
3275 			break;
3276 		case SO_DEBUG:
3277 			if (!checkonly)
3278 				udp->udp_debug = onoff;
3279 			break;
3280 		/*
3281 		 * The following three items are available here,
3282 		 * but are only meaningful to IP.
3283 		 */
3284 		case SO_DONTROUTE:
3285 			if (!checkonly)
3286 				udp->udp_dontroute = onoff;
3287 			break;
3288 		case SO_USELOOPBACK:
3289 			if (!checkonly)
3290 				udp->udp_useloopback = onoff;
3291 			break;
3292 		case SO_BROADCAST:
3293 			if (!checkonly)
3294 				udp->udp_broadcast = onoff;
3295 			break;
3296 
3297 		case SO_SNDBUF:
3298 			if (*i1 > udp_max_buf) {
3299 				*outlenp = 0;
3300 				return (ENOBUFS);
3301 			}
3302 			if (!checkonly) {
3303 				q->q_hiwat = *i1;
3304 				WR(UDP_RD(q))->q_hiwat = *i1;
3305 			}
3306 			break;
3307 		case SO_RCVBUF:
3308 			if (*i1 > udp_max_buf) {
3309 				*outlenp = 0;
3310 				return (ENOBUFS);
3311 			}
3312 			if (!checkonly) {
3313 				RD(q)->q_hiwat = *i1;
3314 				UDP_RD(q)->q_hiwat = *i1;
3315 				(void) mi_set_sth_hiwat(UDP_RD(q),
3316 				    udp_set_rcv_hiwat(udp, *i1));
3317 			}
3318 			break;
3319 		case SO_DGRAM_ERRIND:
3320 			if (!checkonly)
3321 				udp->udp_dgram_errind = onoff;
3322 			break;
3323 		case SO_RECVUCRED:
3324 			if (!checkonly)
3325 				udp->udp_recvucred = onoff;
3326 			break;
3327 		default:
3328 			*outlenp = 0;
3329 			return (EINVAL);
3330 		}
3331 		break;
3332 	case IPPROTO_IP:
3333 		if (udp->udp_family != AF_INET) {
3334 			*outlenp = 0;
3335 			return (ENOPROTOOPT);
3336 		}
3337 		switch (name) {
3338 		case IP_OPTIONS:
3339 		case T_IP_OPTIONS:
3340 			/* Save options for use by IP. */
3341 			if (inlen & 0x3) {
3342 				*outlenp = 0;
3343 				return (EINVAL);
3344 			}
3345 			if (checkonly)
3346 				break;
3347 
3348 			if (udp->udp_ip_snd_options) {
3349 				mi_free((char *)udp->udp_ip_snd_options);
3350 				udp->udp_ip_snd_options_len = 0;
3351 				udp->udp_ip_snd_options = NULL;
3352 			}
3353 			if (inlen) {
3354 				udp->udp_ip_snd_options =
3355 					(uchar_t *)mi_alloc(inlen, BPRI_HI);
3356 				if (udp->udp_ip_snd_options) {
3357 					bcopy(invalp, udp->udp_ip_snd_options,
3358 					    inlen);
3359 					udp->udp_ip_snd_options_len = inlen;
3360 				}
3361 			}
3362 			udp->udp_max_hdr_len = IP_SIMPLE_HDR_LENGTH +
3363 			    UDPH_SIZE + udp->udp_ip_snd_options_len;
3364 			(void) mi_set_sth_wroff(RD(q), udp->udp_max_hdr_len +
3365 			    udp_wroff_extra);
3366 			break;
3367 		case IP_TTL:
3368 			if (!checkonly) {
3369 				udp->udp_ttl = (uchar_t)*i1;
3370 			}
3371 			break;
3372 		case IP_TOS:
3373 		case T_IP_TOS:
3374 			if (!checkonly) {
3375 				udp->udp_type_of_service = (uchar_t)*i1;
3376 			}
3377 			break;
3378 		case IP_MULTICAST_IF: {
3379 			/*
3380 			 * TODO should check OPTMGMT reply and undo this if
3381 			 * there is an error.
3382 			 */
3383 			struct in_addr *inap = (struct in_addr *)invalp;
3384 			if (!checkonly) {
3385 				udp->udp_multicast_if_addr =
3386 				    inap->s_addr;
3387 			}
3388 			break;
3389 		}
3390 		case IP_MULTICAST_TTL:
3391 			if (!checkonly)
3392 				udp->udp_multicast_ttl = *invalp;
3393 			break;
3394 		case IP_MULTICAST_LOOP:
3395 			if (!checkonly)
3396 				connp->conn_multicast_loop = *invalp;
3397 			break;
3398 		case IP_RECVOPTS:
3399 			if (!checkonly)
3400 				udp->udp_recvopts = onoff;
3401 			break;
3402 		case IP_RECVDSTADDR:
3403 			if (!checkonly)
3404 				udp->udp_recvdstaddr = onoff;
3405 			break;
3406 		case IP_RECVIF:
3407 			if (!checkonly)
3408 				udp->udp_recvif = onoff;
3409 			break;
3410 		case IP_RECVSLLA:
3411 			if (!checkonly)
3412 				udp->udp_recvslla = onoff;
3413 			break;
3414 		case IP_RECVTTL:
3415 			if (!checkonly)
3416 				udp->udp_recvttl = onoff;
3417 			break;
3418 		case IP_ADD_MEMBERSHIP:
3419 		case IP_DROP_MEMBERSHIP:
3420 		case IP_BLOCK_SOURCE:
3421 		case IP_UNBLOCK_SOURCE:
3422 		case IP_ADD_SOURCE_MEMBERSHIP:
3423 		case IP_DROP_SOURCE_MEMBERSHIP:
3424 		case MCAST_JOIN_GROUP:
3425 		case MCAST_LEAVE_GROUP:
3426 		case MCAST_BLOCK_SOURCE:
3427 		case MCAST_UNBLOCK_SOURCE:
3428 		case MCAST_JOIN_SOURCE_GROUP:
3429 		case MCAST_LEAVE_SOURCE_GROUP:
3430 		case IP_SEC_OPT:
3431 		case IP_NEXTHOP:
3432 			/*
3433 			 * "soft" error (negative)
3434 			 * option not handled at this level
3435 			 * Do not modify *outlenp.
3436 			 */
3437 			return (-EINVAL);
3438 		case IP_BOUND_IF:
3439 			if (!checkonly)
3440 				udp->udp_bound_if = *i1;
3441 			break;
3442 		case IP_UNSPEC_SRC:
3443 			if (!checkonly)
3444 				udp->udp_unspec_source = onoff;
3445 			break;
3446 		case IP_XMIT_IF:
3447 			if (!checkonly)
3448 				udp->udp_xmit_if = *i1;
3449 			break;
3450 		default:
3451 			*outlenp = 0;
3452 			return (EINVAL);
3453 		}
3454 		break;
3455 	case IPPROTO_IPV6: {
3456 		ip6_pkt_t		*ipp;
3457 		boolean_t		sticky;
3458 
3459 		if (udp->udp_family != AF_INET6) {
3460 			*outlenp = 0;
3461 			return (ENOPROTOOPT);
3462 		}
3463 		/*
3464 		 * Deal with both sticky options and ancillary data
3465 		 */
3466 		if (thisdg_attrs == NULL) {
3467 			/* sticky options, or none */
3468 			ipp = &udp->udp_sticky_ipp;
3469 			sticky = B_TRUE;
3470 		} else {
3471 			/* ancillary data */
3472 			ipp = (ip6_pkt_t *)thisdg_attrs;
3473 			sticky = B_FALSE;
3474 		}
3475 
3476 		switch (name) {
3477 		case IPV6_MULTICAST_IF:
3478 			if (!checkonly)
3479 				udp->udp_multicast_if_index = *i1;
3480 			break;
3481 		case IPV6_UNICAST_HOPS:
3482 			/* -1 means use default */
3483 			if (*i1 < -1 || *i1 > IPV6_MAX_HOPS) {
3484 				*outlenp = 0;
3485 				return (EINVAL);
3486 			}
3487 			if (!checkonly) {
3488 				if (*i1 == -1) {
3489 					udp->udp_ttl = ipp->ipp_unicast_hops =
3490 					    udp_ipv6_hoplimit;
3491 					ipp->ipp_fields &= ~IPPF_UNICAST_HOPS;
3492 					/* Pass modified value to IP. */
3493 					*i1 = udp->udp_ttl;
3494 				} else {
3495 					udp->udp_ttl = ipp->ipp_unicast_hops =
3496 					    (uint8_t)*i1;
3497 					ipp->ipp_fields |= IPPF_UNICAST_HOPS;
3498 				}
3499 				/* Rebuild the header template */
3500 				error = udp_build_hdrs(q, udp);
3501 				if (error != 0) {
3502 					*outlenp = 0;
3503 					return (error);
3504 				}
3505 			}
3506 			break;
3507 		case IPV6_MULTICAST_HOPS:
3508 			/* -1 means use default */
3509 			if (*i1 < -1 || *i1 > IPV6_MAX_HOPS) {
3510 				*outlenp = 0;
3511 				return (EINVAL);
3512 			}
3513 			if (!checkonly) {
3514 				if (*i1 == -1) {
3515 					udp->udp_multicast_ttl =
3516 					    ipp->ipp_multicast_hops =
3517 					    IP_DEFAULT_MULTICAST_TTL;
3518 					ipp->ipp_fields &= ~IPPF_MULTICAST_HOPS;
3519 					/* Pass modified value to IP. */
3520 					*i1 = udp->udp_multicast_ttl;
3521 				} else {
3522 					udp->udp_multicast_ttl =
3523 					    ipp->ipp_multicast_hops =
3524 					    (uint8_t)*i1;
3525 					ipp->ipp_fields |= IPPF_MULTICAST_HOPS;
3526 				}
3527 			}
3528 			break;
3529 		case IPV6_MULTICAST_LOOP:
3530 			if (*i1 != 0 && *i1 != 1) {
3531 				*outlenp = 0;
3532 				return (EINVAL);
3533 			}
3534 			if (!checkonly)
3535 				connp->conn_multicast_loop = *i1;
3536 			break;
3537 		case IPV6_JOIN_GROUP:
3538 		case IPV6_LEAVE_GROUP:
3539 		case MCAST_JOIN_GROUP:
3540 		case MCAST_LEAVE_GROUP:
3541 		case MCAST_BLOCK_SOURCE:
3542 		case MCAST_UNBLOCK_SOURCE:
3543 		case MCAST_JOIN_SOURCE_GROUP:
3544 		case MCAST_LEAVE_SOURCE_GROUP:
3545 			/*
3546 			 * "soft" error (negative)
3547 			 * option not handled at this level
3548 			 * Note: Do not modify *outlenp
3549 			 */
3550 			return (-EINVAL);
3551 		case IPV6_BOUND_IF:
3552 			if (!checkonly)
3553 				udp->udp_bound_if = *i1;
3554 			break;
3555 		case IPV6_UNSPEC_SRC:
3556 			if (!checkonly)
3557 				udp->udp_unspec_source = onoff;
3558 			break;
3559 		/*
3560 		 * Set boolean switches for ancillary data delivery
3561 		 */
3562 		case IPV6_RECVPKTINFO:
3563 			if (!checkonly)
3564 				udp->udp_ipv6_recvpktinfo = onoff;
3565 			break;
3566 		case IPV6_RECVTCLASS:
3567 			if (!checkonly) {
3568 				udp->udp_ipv6_recvtclass = onoff;
3569 			}
3570 			break;
3571 		case IPV6_RECVPATHMTU:
3572 			if (!checkonly) {
3573 				udp->udp_ipv6_recvpathmtu = onoff;
3574 			}
3575 			break;
3576 		case IPV6_RECVHOPLIMIT:
3577 			if (!checkonly)
3578 				udp->udp_ipv6_recvhoplimit = onoff;
3579 			break;
3580 		case IPV6_RECVHOPOPTS:
3581 			if (!checkonly)
3582 				udp->udp_ipv6_recvhopopts = onoff;
3583 			break;
3584 		case IPV6_RECVDSTOPTS:
3585 			if (!checkonly)
3586 				udp->udp_ipv6_recvdstopts = onoff;
3587 			break;
3588 		case _OLD_IPV6_RECVDSTOPTS:
3589 			if (!checkonly)
3590 				udp->udp_old_ipv6_recvdstopts = onoff;
3591 			break;
3592 		case IPV6_RECVRTHDRDSTOPTS:
3593 			if (!checkonly)
3594 				udp->udp_ipv6_recvrthdrdstopts = onoff;
3595 			break;
3596 		case IPV6_RECVRTHDR:
3597 			if (!checkonly)
3598 				udp->udp_ipv6_recvrthdr = onoff;
3599 			break;
3600 		/*
3601 		 * Set sticky options or ancillary data.
3602 		 * If sticky options, (re)build any extension headers
3603 		 * that might be needed as a result.
3604 		 */
3605 		case IPV6_PKTINFO:
3606 			/*
3607 			 * The source address and ifindex are verified
3608 			 * in ip_opt_set(). For ancillary data the
3609 			 * source address is checked in ip_wput_v6.
3610 			 */
3611 			if (inlen != 0 && inlen != sizeof (struct in6_pktinfo))
3612 				return (EINVAL);
3613 			if (checkonly)
3614 				break;
3615 
3616 			if (inlen == 0) {
3617 				ipp->ipp_fields &= ~(IPPF_IFINDEX|IPPF_ADDR);
3618 				ipp->ipp_sticky_ignored |=
3619 				    (IPPF_IFINDEX|IPPF_ADDR);
3620 			} else {
3621 				struct in6_pktinfo *pkti;
3622 
3623 				pkti = (struct in6_pktinfo *)invalp;
3624 				ipp->ipp_ifindex = pkti->ipi6_ifindex;
3625 				ipp->ipp_addr = pkti->ipi6_addr;
3626 				if (ipp->ipp_ifindex != 0)
3627 					ipp->ipp_fields |= IPPF_IFINDEX;
3628 				else
3629 					ipp->ipp_fields &= ~IPPF_IFINDEX;
3630 				if (!IN6_IS_ADDR_UNSPECIFIED(
3631 				    &ipp->ipp_addr))
3632 					ipp->ipp_fields |= IPPF_ADDR;
3633 				else
3634 					ipp->ipp_fields &= ~IPPF_ADDR;
3635 			}
3636 			if (sticky) {
3637 				error = udp_build_hdrs(q, udp);
3638 				if (error != 0)
3639 					return (error);
3640 			}
3641 			break;
3642 		case IPV6_HOPLIMIT:
3643 			if (sticky)
3644 				return (EINVAL);
3645 			if (inlen != 0 && inlen != sizeof (int))
3646 				return (EINVAL);
3647 			if (checkonly)
3648 				break;
3649 
3650 			if (inlen == 0) {
3651 				ipp->ipp_fields &= ~IPPF_HOPLIMIT;
3652 				ipp->ipp_sticky_ignored |= IPPF_HOPLIMIT;
3653 			} else {
3654 				if (*i1 > 255 || *i1 < -1)
3655 					return (EINVAL);
3656 				if (*i1 == -1)
3657 					ipp->ipp_hoplimit = udp_ipv6_hoplimit;
3658 				else
3659 					ipp->ipp_hoplimit = *i1;
3660 				ipp->ipp_fields |= IPPF_HOPLIMIT;
3661 			}
3662 			break;
3663 		case IPV6_TCLASS:
3664 			if (inlen != 0 && inlen != sizeof (int))
3665 				return (EINVAL);
3666 			if (checkonly)
3667 				break;
3668 
3669 			if (inlen == 0) {
3670 				ipp->ipp_fields &= ~IPPF_TCLASS;
3671 				ipp->ipp_sticky_ignored |= IPPF_TCLASS;
3672 			} else {
3673 				if (*i1 > 255 || *i1 < -1)
3674 					return (EINVAL);
3675 				if (*i1 == -1)
3676 					ipp->ipp_tclass = 0;
3677 				else
3678 					ipp->ipp_tclass = *i1;
3679 				ipp->ipp_fields |= IPPF_TCLASS;
3680 			}
3681 			if (sticky) {
3682 				error = udp_build_hdrs(q, udp);
3683 				if (error != 0)
3684 					return (error);
3685 			}
3686 			break;
3687 		case IPV6_NEXTHOP:
3688 			/*
3689 			 * IP will verify that the nexthop is reachable
3690 			 * and fail for sticky options.
3691 			 */
3692 			if (inlen != 0 && inlen != sizeof (sin6_t))
3693 				return (EINVAL);
3694 			if (checkonly)
3695 				break;
3696 
3697 			if (inlen == 0) {
3698 				ipp->ipp_fields &= ~IPPF_NEXTHOP;
3699 				ipp->ipp_sticky_ignored |= IPPF_NEXTHOP;
3700 			} else {
3701 				sin6_t *sin6 = (sin6_t *)invalp;
3702 
3703 				if (sin6->sin6_family != AF_INET6)
3704 					return (EAFNOSUPPORT);
3705 				if (IN6_IS_ADDR_V4MAPPED(
3706 				    &sin6->sin6_addr))
3707 					return (EADDRNOTAVAIL);
3708 				ipp->ipp_nexthop = sin6->sin6_addr;
3709 				if (!IN6_IS_ADDR_UNSPECIFIED(
3710 				    &ipp->ipp_nexthop))
3711 					ipp->ipp_fields |= IPPF_NEXTHOP;
3712 				else
3713 					ipp->ipp_fields &= ~IPPF_NEXTHOP;
3714 			}
3715 			if (sticky) {
3716 				error = udp_build_hdrs(q, udp);
3717 				if (error != 0)
3718 					return (error);
3719 			}
3720 			break;
3721 		case IPV6_HOPOPTS: {
3722 			ip6_hbh_t *hopts = (ip6_hbh_t *)invalp;
3723 			/*
3724 			 * Sanity checks - minimum size, size a multiple of
3725 			 * eight bytes, and matching size passed in.
3726 			 */
3727 			if (inlen != 0 &&
3728 			    inlen != (8 * (hopts->ip6h_len + 1)))
3729 				return (EINVAL);
3730 
3731 			if (checkonly)
3732 				break;
3733 
3734 			if (inlen == 0) {
3735 				if (sticky &&
3736 				    (ipp->ipp_fields & IPPF_HOPOPTS) != 0) {
3737 					kmem_free(ipp->ipp_hopopts,
3738 					    ipp->ipp_hopoptslen);
3739 					ipp->ipp_hopopts = NULL;
3740 					ipp->ipp_hopoptslen = 0;
3741 				}
3742 				ipp->ipp_fields &= ~IPPF_HOPOPTS;
3743 				ipp->ipp_sticky_ignored |= IPPF_HOPOPTS;
3744 			} else {
3745 				error = udp_pkt_set(invalp, inlen, sticky,
3746 				    (uchar_t **)&ipp->ipp_hopopts,
3747 				    &ipp->ipp_hopoptslen);
3748 				if (error != 0)
3749 					return (error);
3750 				ipp->ipp_fields |= IPPF_HOPOPTS;
3751 			}
3752 			if (sticky) {
3753 				error = udp_build_hdrs(q, udp);
3754 				if (error != 0)
3755 					return (error);
3756 			}
3757 			break;
3758 		}
3759 		case IPV6_RTHDRDSTOPTS: {
3760 			ip6_dest_t *dopts = (ip6_dest_t *)invalp;
3761 
3762 			/*
3763 			 * Sanity checks - minimum size, size a multiple of
3764 			 * eight bytes, and matching size passed in.
3765 			 */
3766 			if (inlen != 0 &&
3767 			    inlen != (8 * (dopts->ip6d_len + 1)))
3768 				return (EINVAL);
3769 
3770 			if (checkonly)
3771 				break;
3772 
3773 			if (inlen == 0) {
3774 				if (sticky &&
3775 				    (ipp->ipp_fields & IPPF_RTDSTOPTS) != 0) {
3776 					kmem_free(ipp->ipp_rtdstopts,
3777 					    ipp->ipp_rtdstoptslen);
3778 					ipp->ipp_rtdstopts = NULL;
3779 					ipp->ipp_rtdstoptslen = 0;
3780 				}
3781 
3782 				ipp->ipp_fields &= ~IPPF_RTDSTOPTS;
3783 				ipp->ipp_sticky_ignored |= IPPF_RTDSTOPTS;
3784 			} else {
3785 				error = udp_pkt_set(invalp, inlen, sticky,
3786 				    (uchar_t **)&ipp->ipp_rtdstopts,
3787 				    &ipp->ipp_rtdstoptslen);
3788 				if (error != 0)
3789 					return (error);
3790 				ipp->ipp_fields |= IPPF_RTDSTOPTS;
3791 			}
3792 			if (sticky) {
3793 				error = udp_build_hdrs(q, udp);
3794 				if (error != 0)
3795 					return (error);
3796 			}
3797 			break;
3798 		}
3799 		case IPV6_DSTOPTS: {
3800 			ip6_dest_t *dopts = (ip6_dest_t *)invalp;
3801 
3802 			/*
3803 			 * Sanity checks - minimum size, size a multiple of
3804 			 * eight bytes, and matching size passed in.
3805 			 */
3806 			if (inlen != 0 &&
3807 			    inlen != (8 * (dopts->ip6d_len + 1)))
3808 				return (EINVAL);
3809 
3810 			if (checkonly)
3811 				break;
3812 
3813 			if (inlen == 0) {
3814 				if (sticky &&
3815 				    (ipp->ipp_fields & IPPF_DSTOPTS) != 0) {
3816 					kmem_free(ipp->ipp_dstopts,
3817 					    ipp->ipp_dstoptslen);
3818 					ipp->ipp_dstopts = NULL;
3819 					ipp->ipp_dstoptslen = 0;
3820 				}
3821 				ipp->ipp_fields &= ~IPPF_DSTOPTS;
3822 				ipp->ipp_sticky_ignored |= IPPF_DSTOPTS;
3823 			} else {
3824 				error = udp_pkt_set(invalp, inlen, sticky,
3825 				    (uchar_t **)&ipp->ipp_dstopts,
3826 				    &ipp->ipp_dstoptslen);
3827 				if (error != 0)
3828 					return (error);
3829 				ipp->ipp_fields |= IPPF_DSTOPTS;
3830 			}
3831 			if (sticky) {
3832 				error = udp_build_hdrs(q, udp);
3833 				if (error != 0)
3834 					return (error);
3835 			}
3836 			break;
3837 		}
3838 		case IPV6_RTHDR: {
3839 			ip6_rthdr_t *rt = (ip6_rthdr_t *)invalp;
3840 
3841 			/*
3842 			 * Sanity checks - minimum size, size a multiple of
3843 			 * eight bytes, and matching size passed in.
3844 			 */
3845 			if (inlen != 0 &&
3846 			    inlen != (8 * (rt->ip6r_len + 1)))
3847 				return (EINVAL);
3848 
3849 			if (checkonly)
3850 				break;
3851 
3852 			if (inlen == 0) {
3853 				if (sticky &&
3854 				    (ipp->ipp_fields & IPPF_RTHDR) != 0) {
3855 					kmem_free(ipp->ipp_rthdr,
3856 					    ipp->ipp_rthdrlen);
3857 					ipp->ipp_rthdr = NULL;
3858 					ipp->ipp_rthdrlen = 0;
3859 				}
3860 				ipp->ipp_fields &= ~IPPF_RTHDR;
3861 				ipp->ipp_sticky_ignored |= IPPF_RTHDR;
3862 			} else {
3863 				error = udp_pkt_set(invalp, inlen, sticky,
3864 				    (uchar_t **)&ipp->ipp_rthdr,
3865 				    &ipp->ipp_rthdrlen);
3866 				if (error != 0)
3867 					return (error);
3868 				ipp->ipp_fields |= IPPF_RTHDR;
3869 			}
3870 			if (sticky) {
3871 				error = udp_build_hdrs(q, udp);
3872 				if (error != 0)
3873 					return (error);
3874 			}
3875 			break;
3876 		}
3877 
3878 		case IPV6_DONTFRAG:
3879 			if (checkonly)
3880 				break;
3881 
3882 			if (onoff) {
3883 				ipp->ipp_fields |= IPPF_DONTFRAG;
3884 			} else {
3885 				ipp->ipp_fields &= ~IPPF_DONTFRAG;
3886 			}
3887 			break;
3888 
3889 		case IPV6_USE_MIN_MTU:
3890 			if (inlen != sizeof (int))
3891 				return (EINVAL);
3892 
3893 			if (*i1 < -1 || *i1 > 1)
3894 				return (EINVAL);
3895 
3896 			if (checkonly)
3897 				break;
3898 
3899 			ipp->ipp_fields |= IPPF_USE_MIN_MTU;
3900 			ipp->ipp_use_min_mtu = *i1;
3901 			break;
3902 
3903 		case IPV6_BOUND_PIF:
3904 		case IPV6_SEC_OPT:
3905 		case IPV6_DONTFAILOVER_IF:
3906 		case IPV6_SRC_PREFERENCES:
3907 		case IPV6_V6ONLY:
3908 			/* Handled at the IP level */
3909 			return (-EINVAL);
3910 		default:
3911 			*outlenp = 0;
3912 			return (EINVAL);
3913 		}
3914 		break;
3915 		}		/* end IPPROTO_IPV6 */
3916 	case IPPROTO_UDP:
3917 		switch (name) {
3918 		case UDP_ANONPRIVBIND:
3919 			if ((error = secpolicy_net_privaddr(cr, 0)) != 0) {
3920 				*outlenp = 0;
3921 				return (error);
3922 			}
3923 			if (!checkonly) {
3924 				udp->udp_anon_priv_bind = onoff;
3925 			}
3926 			break;
3927 		case UDP_EXCLBIND:
3928 			if (!checkonly)
3929 				udp->udp_exclbind = onoff;
3930 			break;
3931 		case UDP_RCVHDR:
3932 			if (!checkonly)
3933 				udp->udp_rcvhdr = onoff;
3934 			break;
3935 		default:
3936 			*outlenp = 0;
3937 			return (EINVAL);
3938 		}
3939 		break;
3940 	default:
3941 		*outlenp = 0;
3942 		return (EINVAL);
3943 	}
3944 	/*
3945 	 * Common case of OK return with outval same as inval.
3946 	 */
3947 	if (invalp != outvalp) {
3948 		/* don't trust bcopy for identical src/dst */
3949 		(void) bcopy(invalp, outvalp, inlen);
3950 	}
3951 	*outlenp = inlen;
3952 	return (0);
3953 }
3954 
3955 /*
3956  * Update udp_sticky_hdrs based on udp_sticky_ipp, udp_v6src, and udp_ttl.
3957  * The headers include ip6i_t (if needed), ip6_t, any sticky extension
3958  * headers, and the udp header.
3959  * Returns failure if can't allocate memory.
3960  */
3961 static int
3962 udp_build_hdrs(queue_t *q, udp_t *udp)
3963 {
3964 	uchar_t	*hdrs;
3965 	uint_t	hdrs_len;
3966 	ip6_t	*ip6h;
3967 	ip6i_t	*ip6i;
3968 	udpha_t	*udpha;
3969 	ip6_pkt_t *ipp = &udp->udp_sticky_ipp;
3970 
3971 	hdrs_len = ip_total_hdrs_len_v6(ipp) + UDPH_SIZE;
3972 	ASSERT(hdrs_len != 0);
3973 	if (hdrs_len != udp->udp_sticky_hdrs_len) {
3974 		/* Need to reallocate */
3975 		hdrs = kmem_alloc(hdrs_len, KM_NOSLEEP);
3976 		if (hdrs == NULL)
3977 			return (ENOMEM);
3978 
3979 		if (udp->udp_sticky_hdrs_len != 0) {
3980 			kmem_free(udp->udp_sticky_hdrs,
3981 			    udp->udp_sticky_hdrs_len);
3982 		}
3983 		udp->udp_sticky_hdrs = hdrs;
3984 		udp->udp_sticky_hdrs_len = hdrs_len;
3985 	}
3986 	ip_build_hdrs_v6(udp->udp_sticky_hdrs,
3987 	    udp->udp_sticky_hdrs_len - UDPH_SIZE, ipp, IPPROTO_UDP);
3988 
3989 	/* Set header fields not in ipp */
3990 	if (ipp->ipp_fields & IPPF_HAS_IP6I) {
3991 		ip6i = (ip6i_t *)udp->udp_sticky_hdrs;
3992 		ip6h = (ip6_t *)&ip6i[1];
3993 	} else {
3994 		ip6h = (ip6_t *)udp->udp_sticky_hdrs;
3995 	}
3996 
3997 	if (!(ipp->ipp_fields & IPPF_ADDR))
3998 		ip6h->ip6_src = udp->udp_v6src;
3999 
4000 	udpha = (udpha_t *)(udp->udp_sticky_hdrs + hdrs_len - UDPH_SIZE);
4001 	udpha->uha_src_port = udp->udp_port;
4002 
4003 	/* Try to get everything in a single mblk */
4004 	if (hdrs_len > udp->udp_max_hdr_len) {
4005 		udp->udp_max_hdr_len = hdrs_len;
4006 		(void) mi_set_sth_wroff(RD(q), udp->udp_max_hdr_len +
4007 		    udp_wroff_extra);
4008 	}
4009 	return (0);
4010 }
4011 
4012 /*
4013  * Set optbuf and optlen for the option.
4014  * If sticky is set allocate memory (if not already present).
4015  * Otherwise just point optbuf and optlen at invalp and inlen.
4016  * Returns failure if memory can not be allocated.
4017  */
4018 static int
4019 udp_pkt_set(uchar_t *invalp, uint_t inlen, boolean_t sticky,
4020     uchar_t **optbufp, uint_t *optlenp)
4021 {
4022 	uchar_t *optbuf;
4023 
4024 	if (!sticky) {
4025 		*optbufp = invalp;
4026 		*optlenp = inlen;
4027 		return (0);
4028 	}
4029 	if (inlen == *optlenp) {
4030 		/* Unchanged length - no need to realocate */
4031 		bcopy(invalp, *optbufp, inlen);
4032 		return (0);
4033 	}
4034 	if (inlen != 0) {
4035 		/* Allocate new buffer before free */
4036 		optbuf = kmem_alloc(inlen, KM_NOSLEEP);
4037 		if (optbuf == NULL)
4038 			return (ENOMEM);
4039 	} else {
4040 		optbuf = NULL;
4041 	}
4042 	/* Free old buffer */
4043 	if (*optlenp != 0)
4044 		kmem_free(*optbufp, *optlenp);
4045 
4046 	bcopy(invalp, optbuf, inlen);
4047 	*optbufp = optbuf;
4048 	*optlenp = inlen;
4049 	return (0);
4050 }
4051 
4052 /*
4053  * This routine retrieves the value of an ND variable in a udpparam_t
4054  * structure.  It is called through nd_getset when a user reads the
4055  * variable.
4056  */
4057 /* ARGSUSED */
4058 static int
4059 udp_param_get(queue_t *q, mblk_t *mp, caddr_t cp, cred_t *cr)
4060 {
4061 	udpparam_t *udppa = (udpparam_t *)cp;
4062 
4063 	(void) mi_mpprintf(mp, "%d", udppa->udp_param_value);
4064 	return (0);
4065 }
4066 
4067 /*
4068  * Walk through the param array specified registering each element with the
4069  * named dispatch (ND) handler.
4070  */
4071 static boolean_t
4072 udp_param_register(udpparam_t *udppa, int cnt)
4073 {
4074 	for (; cnt-- > 0; udppa++) {
4075 		if (udppa->udp_param_name && udppa->udp_param_name[0]) {
4076 			if (!nd_load(&udp_g_nd, udppa->udp_param_name,
4077 			    udp_param_get, udp_param_set,
4078 			    (caddr_t)udppa)) {
4079 				nd_free(&udp_g_nd);
4080 				return (B_FALSE);
4081 			}
4082 		}
4083 	}
4084 	if (!nd_load(&udp_g_nd, "udp_extra_priv_ports",
4085 	    udp_extra_priv_ports_get, NULL, NULL)) {
4086 		nd_free(&udp_g_nd);
4087 		return (B_FALSE);
4088 	}
4089 	if (!nd_load(&udp_g_nd, "udp_extra_priv_ports_add",
4090 	    NULL, udp_extra_priv_ports_add, NULL)) {
4091 		nd_free(&udp_g_nd);
4092 		return (B_FALSE);
4093 	}
4094 	if (!nd_load(&udp_g_nd, "udp_extra_priv_ports_del",
4095 	    NULL, udp_extra_priv_ports_del, NULL)) {
4096 		nd_free(&udp_g_nd);
4097 		return (B_FALSE);
4098 	}
4099 	if (!nd_load(&udp_g_nd, "udp_status", udp_status_report, NULL,
4100 	    NULL)) {
4101 		nd_free(&udp_g_nd);
4102 		return (B_FALSE);
4103 	}
4104 	if (!nd_load(&udp_g_nd, "udp_bind_hash", udp_bind_hash_report, NULL,
4105 	    NULL)) {
4106 		nd_free(&udp_g_nd);
4107 		return (B_FALSE);
4108 	}
4109 	return (B_TRUE);
4110 }
4111 
4112 /* This routine sets an ND variable in a udpparam_t structure. */
4113 /* ARGSUSED */
4114 static int
4115 udp_param_set(queue_t *q, mblk_t *mp, char *value, caddr_t cp, cred_t *cr)
4116 {
4117 	long		new_value;
4118 	udpparam_t	*udppa = (udpparam_t *)cp;
4119 
4120 	/*
4121 	 * Fail the request if the new value does not lie within the
4122 	 * required bounds.
4123 	 */
4124 	if (ddi_strtol(value, NULL, 10, &new_value) != 0 ||
4125 	    new_value < udppa->udp_param_min ||
4126 	    new_value > udppa->udp_param_max) {
4127 		return (EINVAL);
4128 	}
4129 
4130 	/* Set the new value */
4131 	udppa->udp_param_value = new_value;
4132 	return (0);
4133 }
4134 
4135 static void
4136 udp_input(conn_t *connp, mblk_t *mp)
4137 {
4138 	struct T_unitdata_ind	*tudi;
4139 	uchar_t			*rptr;		/* Pointer to IP header */
4140 	int			hdr_length;	/* Length of IP+UDP headers */
4141 	int			udi_size;	/* Size of T_unitdata_ind */
4142 	int			mp_len;
4143 	udp_t			*udp;
4144 	udpha_t			*udpha;
4145 	int			ipversion;
4146 	ip6_pkt_t		ipp;
4147 	ip6_t			*ip6h;
4148 	ip6i_t			*ip6i;
4149 	mblk_t			*mp1;
4150 	mblk_t			*options_mp = NULL;
4151 	in_pktinfo_t		*pinfo = NULL;
4152 	cred_t			*cr = NULL;
4153 	queue_t			*q = connp->conn_rq;
4154 	pid_t			cpid;
4155 
4156 	TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_START,
4157 	    "udp_rput_start: q %p mp %p", q, mp);
4158 
4159 	udp = connp->conn_udp;
4160 	rptr = mp->b_rptr;
4161 	ASSERT(DB_TYPE(mp) == M_DATA || DB_TYPE(mp) == M_CTL);
4162 	ASSERT(OK_32PTR(rptr));
4163 
4164 	/*
4165 	 * IP should have prepended the options data in an M_CTL
4166 	 * Check M_CTL "type" to make sure are not here bcos of
4167 	 * a valid ICMP message
4168 	 */
4169 	if (DB_TYPE(mp) == M_CTL) {
4170 		if (MBLKL(mp) == sizeof (in_pktinfo_t) &&
4171 		    ((in_pktinfo_t *)mp->b_rptr)->in_pkt_ulp_type ==
4172 		    IN_PKTINFO) {
4173 			/*
4174 			 * IP_RECVIF or IP_RECVSLLA information has been
4175 			 * appended to the packet by IP. We need to
4176 			 * extract the mblk and adjust the rptr
4177 			 */
4178 			pinfo = (in_pktinfo_t *)mp->b_rptr;
4179 			options_mp = mp;
4180 			mp = mp->b_cont;
4181 			rptr = mp->b_rptr;
4182 			UDP_STAT(udp_in_pktinfo);
4183 		} else {
4184 			/*
4185 			 * ICMP messages.
4186 			 */
4187 			udp_icmp_error(q, mp);
4188 			TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4189 				"udp_rput_end: q %p (%S)", q, "m_ctl");
4190 			return;
4191 		}
4192 	}
4193 
4194 	mp_len = msgdsize(mp);
4195 	/*
4196 	 * This is the inbound data path.
4197 	 * First, we check to make sure the IP version number is correct,
4198 	 * and then pull the IP and UDP headers into the first mblk.
4199 	 * Assume IP provides aligned packets - otherwise toss.
4200 	 * Also, check if we have a complete IP header.
4201 	 */
4202 
4203 	/* Initialize regardless if ipversion is IPv4 or IPv6 */
4204 	ipp.ipp_fields = 0;
4205 
4206 	ipversion = IPH_HDR_VERSION(rptr);
4207 	switch (ipversion) {
4208 	case IPV4_VERSION:
4209 		ASSERT(MBLKL(mp) >= sizeof (ipha_t));
4210 		ASSERT(((ipha_t *)rptr)->ipha_protocol == IPPROTO_UDP);
4211 		hdr_length = IPH_HDR_LENGTH(rptr) + UDPH_SIZE;
4212 		if ((hdr_length > IP_SIMPLE_HDR_LENGTH + UDPH_SIZE) ||
4213 		    (udp->udp_ip_rcv_options_len)) {
4214 			/*
4215 			 * Handle IPv4 packets with options outside of the
4216 			 * main data path. Not needed for AF_INET6 sockets
4217 			 * since they don't support a getsockopt of IP_OPTIONS.
4218 			 */
4219 			if (udp->udp_family == AF_INET6)
4220 				break;
4221 			/*
4222 			 * UDP length check performed for IPv4 packets with
4223 			 * options to check whether UDP length specified in
4224 			 * the header is the same as the physical length of
4225 			 * the packet.
4226 			 */
4227 			udpha = (udpha_t *)(rptr + (hdr_length - UDPH_SIZE));
4228 			if (mp_len != (ntohs(udpha->uha_length) +
4229 			    hdr_length - UDPH_SIZE)) {
4230 				goto tossit;
4231 			}
4232 			/*
4233 			 * Handle the case where the packet has IP options
4234 			 * and the IP_RECVSLLA & IP_RECVIF are set
4235 			 */
4236 			if (pinfo != NULL)
4237 				mp = options_mp;
4238 			udp_become_writer(connp, mp, udp_rput_other_wrapper,
4239 			    SQTAG_UDP_INPUT);
4240 			TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4241 				"udp_rput_end: q %p (%S)", q, "end");
4242 			return;
4243 		}
4244 
4245 		/* Handle IPV6_RECVHOPLIMIT. */
4246 		if ((udp->udp_family == AF_INET6) && (pinfo != NULL) &&
4247 		    udp->udp_ipv6_recvpktinfo) {
4248 			if (pinfo->in_pkt_flags & IPF_RECVIF) {
4249 				ipp.ipp_fields |= IPPF_IFINDEX;
4250 				ipp.ipp_ifindex = pinfo->in_pkt_ifindex;
4251 			}
4252 		}
4253 		break;
4254 	case IPV6_VERSION:
4255 		/*
4256 		 * IPv6 packets can only be received by applications
4257 		 * that are prepared to receive IPv6 addresses.
4258 		 * The IP fanout must ensure this.
4259 		 */
4260 		ASSERT(udp->udp_family == AF_INET6);
4261 
4262 		ip6h = (ip6_t *)rptr;
4263 		ASSERT((uchar_t *)&ip6h[1] <= mp->b_wptr);
4264 
4265 		if (ip6h->ip6_nxt != IPPROTO_UDP) {
4266 			uint8_t nexthdrp;
4267 			/* Look for ifindex information */
4268 			if (ip6h->ip6_nxt == IPPROTO_RAW) {
4269 				ip6i = (ip6i_t *)ip6h;
4270 				if ((uchar_t *)&ip6i[1] > mp->b_wptr)
4271 					goto tossit;
4272 
4273 				if (ip6i->ip6i_flags & IP6I_IFINDEX) {
4274 					ASSERT(ip6i->ip6i_ifindex != 0);
4275 					ipp.ipp_fields |= IPPF_IFINDEX;
4276 					ipp.ipp_ifindex = ip6i->ip6i_ifindex;
4277 				}
4278 				rptr = (uchar_t *)&ip6i[1];
4279 				mp->b_rptr = rptr;
4280 				if (rptr == mp->b_wptr) {
4281 					mp1 = mp->b_cont;
4282 					freeb(mp);
4283 					mp = mp1;
4284 					rptr = mp->b_rptr;
4285 				}
4286 				if (MBLKL(mp) < (IPV6_HDR_LEN + UDPH_SIZE))
4287 					goto tossit;
4288 				ip6h = (ip6_t *)rptr;
4289 				mp_len = msgdsize(mp);
4290 			}
4291 			/*
4292 			 * Find any potentially interesting extension headers
4293 			 * as well as the length of the IPv6 + extension
4294 			 * headers.
4295 			 */
4296 			hdr_length = ip_find_hdr_v6(mp, ip6h, &ipp, &nexthdrp) +
4297 			    UDPH_SIZE;
4298 			ASSERT(nexthdrp == IPPROTO_UDP);
4299 		} else {
4300 			hdr_length = IPV6_HDR_LEN + UDPH_SIZE;
4301 			ip6i = NULL;
4302 		}
4303 		break;
4304 	default:
4305 		ASSERT(0);
4306 	}
4307 
4308 	/*
4309 	 * IP inspected the UDP header thus all of it must be in the mblk.
4310 	 * UDP length check is performed for IPv6 packets and IPv4 packets
4311 	 * without options to check if the size of the packet as specified
4312 	 * by the header is the same as the physical size of the packet.
4313 	 */
4314 	udpha = (udpha_t *)(rptr + (hdr_length - UDPH_SIZE));
4315 	if ((MBLKL(mp) < hdr_length) ||
4316 	    (mp_len != (ntohs(udpha->uha_length) + hdr_length - UDPH_SIZE))) {
4317 		goto tossit;
4318 	}
4319 
4320 	/* Walk past the headers. */
4321 	if (!udp->udp_rcvhdr) {
4322 		mp->b_rptr = rptr + hdr_length;
4323 		mp_len -= hdr_length;
4324 	}
4325 
4326 	/*
4327 	 * This is the inbound data path.  Packets are passed upstream as
4328 	 * T_UNITDATA_IND messages with full IP headers still attached.
4329 	 */
4330 	if (udp->udp_family == AF_INET) {
4331 		sin_t *sin;
4332 
4333 		ASSERT(IPH_HDR_VERSION((ipha_t *)rptr) == IPV4_VERSION);
4334 
4335 		/*
4336 		 * Normally only send up the address.
4337 		 * If IP_RECVDSTADDR is set we include the destination IP
4338 		 * address as an option. With IP_RECVOPTS we include all
4339 		 * the IP options. Only ip_rput_other() handles packets
4340 		 * that contain IP options.
4341 		 */
4342 		udi_size = sizeof (struct T_unitdata_ind) + sizeof (sin_t);
4343 		if (udp->udp_recvdstaddr) {
4344 			udi_size += sizeof (struct T_opthdr) +
4345 			    sizeof (struct in_addr);
4346 			UDP_STAT(udp_in_recvdstaddr);
4347 		}
4348 
4349 		/*
4350 		 * If the IP_RECVSLLA or the IP_RECVIF is set then allocate
4351 		 * space accordingly
4352 		 */
4353 		if (udp->udp_recvif && (pinfo != NULL) &&
4354 		    (pinfo->in_pkt_flags & IPF_RECVIF)) {
4355 			udi_size += sizeof (struct T_opthdr) + sizeof (uint_t);
4356 			UDP_STAT(udp_in_recvif);
4357 		}
4358 
4359 		if (udp->udp_recvslla && (pinfo != NULL) &&
4360 		    (pinfo->in_pkt_flags & IPF_RECVSLLA)) {
4361 			udi_size += sizeof (struct T_opthdr) +
4362 			    sizeof (struct sockaddr_dl);
4363 			UDP_STAT(udp_in_recvslla);
4364 		}
4365 
4366 		if (udp->udp_recvucred && (cr = DB_CRED(mp)) != NULL) {
4367 			udi_size += sizeof (struct T_opthdr) + ucredsize;
4368 			cpid = DB_CPID(mp);
4369 			UDP_STAT(udp_in_recvucred);
4370 		}
4371 		/*
4372 		 * If IP_RECVTTL is set allocate the appropriate sized buffer
4373 		 */
4374 		if (udp->udp_recvttl) {
4375 			udi_size += sizeof (struct T_opthdr) + sizeof (uint8_t);
4376 			UDP_STAT(udp_in_recvttl);
4377 		}
4378 
4379 		ASSERT(IPH_HDR_LENGTH((ipha_t *)rptr) == IP_SIMPLE_HDR_LENGTH);
4380 
4381 		/* Allocate a message block for the T_UNITDATA_IND structure. */
4382 		mp1 = allocb(udi_size, BPRI_MED);
4383 		if (mp1 == NULL) {
4384 			freemsg(mp);
4385 			if (options_mp != NULL)
4386 				freeb(options_mp);
4387 			TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4388 				"udp_rput_end: q %p (%S)", q, "allocbfail");
4389 			BUMP_MIB(&udp_mib, udpInErrors);
4390 			return;
4391 		}
4392 		mp1->b_cont = mp;
4393 		mp = mp1;
4394 		mp->b_datap->db_type = M_PROTO;
4395 		tudi = (struct T_unitdata_ind *)mp->b_rptr;
4396 		mp->b_wptr = (uchar_t *)tudi + udi_size;
4397 		tudi->PRIM_type = T_UNITDATA_IND;
4398 		tudi->SRC_length = sizeof (sin_t);
4399 		tudi->SRC_offset = sizeof (struct T_unitdata_ind);
4400 		tudi->OPT_offset = sizeof (struct T_unitdata_ind) +
4401 		    sizeof (sin_t);
4402 		udi_size -= (sizeof (struct T_unitdata_ind) + sizeof (sin_t));
4403 		tudi->OPT_length = udi_size;
4404 		sin = (sin_t *)&tudi[1];
4405 		sin->sin_addr.s_addr = ((ipha_t *)rptr)->ipha_src;
4406 		sin->sin_port =	udpha->uha_src_port;
4407 		sin->sin_family = udp->udp_family;
4408 		*(uint32_t *)&sin->sin_zero[0] = 0;
4409 		*(uint32_t *)&sin->sin_zero[4] = 0;
4410 
4411 		/*
4412 		 * Add options if IP_RECVDSTADDR, IP_RECVIF, IP_RECVSLLA or
4413 		 * IP_RECVTTL has been set.
4414 		 */
4415 		if (udi_size != 0) {
4416 			/*
4417 			 * Copy in destination address before options to avoid
4418 			 * any padding issues.
4419 			 */
4420 			char *dstopt;
4421 
4422 			dstopt = (char *)&sin[1];
4423 			if (udp->udp_recvdstaddr) {
4424 				struct T_opthdr *toh;
4425 				ipaddr_t *dstptr;
4426 
4427 				toh = (struct T_opthdr *)dstopt;
4428 				toh->level = IPPROTO_IP;
4429 				toh->name = IP_RECVDSTADDR;
4430 				toh->len = sizeof (struct T_opthdr) +
4431 				    sizeof (ipaddr_t);
4432 				toh->status = 0;
4433 				dstopt += sizeof (struct T_opthdr);
4434 				dstptr = (ipaddr_t *)dstopt;
4435 				*dstptr = ((ipha_t *)rptr)->ipha_dst;
4436 				dstopt += sizeof (ipaddr_t);
4437 				udi_size -= toh->len;
4438 			}
4439 
4440 			if (udp->udp_recvslla && (pinfo != NULL) &&
4441 			    (pinfo->in_pkt_flags & IPF_RECVSLLA)) {
4442 
4443 				struct T_opthdr *toh;
4444 				struct sockaddr_dl	*dstptr;
4445 
4446 				toh = (struct T_opthdr *)dstopt;
4447 				toh->level = IPPROTO_IP;
4448 				toh->name = IP_RECVSLLA;
4449 				toh->len = sizeof (struct T_opthdr) +
4450 					sizeof (struct sockaddr_dl);
4451 				toh->status = 0;
4452 				dstopt += sizeof (struct T_opthdr);
4453 				dstptr = (struct sockaddr_dl *)dstopt;
4454 				bcopy(&pinfo->in_pkt_slla, dstptr,
4455 				    sizeof (struct sockaddr_dl));
4456 				dstopt += sizeof (struct sockaddr_dl);
4457 				udi_size -= toh->len;
4458 			}
4459 
4460 			if (udp->udp_recvif && (pinfo != NULL) &&
4461 			    (pinfo->in_pkt_flags & IPF_RECVIF)) {
4462 
4463 				struct T_opthdr *toh;
4464 				uint_t		*dstptr;
4465 
4466 				toh = (struct T_opthdr *)dstopt;
4467 				toh->level = IPPROTO_IP;
4468 				toh->name = IP_RECVIF;
4469 				toh->len = sizeof (struct T_opthdr) +
4470 					sizeof (uint_t);
4471 				toh->status = 0;
4472 				dstopt += sizeof (struct T_opthdr);
4473 				dstptr = (uint_t *)dstopt;
4474 				*dstptr = pinfo->in_pkt_ifindex;
4475 				dstopt += sizeof (uint_t);
4476 				udi_size -= toh->len;
4477 			}
4478 
4479 			if (cr != NULL) {
4480 				struct T_opthdr *toh;
4481 
4482 				toh = (struct T_opthdr *)dstopt;
4483 				toh->level = SOL_SOCKET;
4484 				toh->name = SCM_UCRED;
4485 				toh->len = sizeof (struct T_opthdr) + ucredsize;
4486 				toh->status = 0;
4487 				(void) cred2ucred(cr, cpid, &toh[1]);
4488 				dstopt += toh->len;
4489 				udi_size -= toh->len;
4490 			}
4491 
4492 			if (udp->udp_recvttl) {
4493 				struct	T_opthdr *toh;
4494 				uint8_t	*dstptr;
4495 
4496 				toh = (struct T_opthdr *)dstopt;
4497 				toh->level = IPPROTO_IP;
4498 				toh->name = IP_RECVTTL;
4499 				toh->len = sizeof (struct T_opthdr) +
4500 				    sizeof (uint8_t);
4501 				toh->status = 0;
4502 				dstopt += sizeof (struct T_opthdr);
4503 				dstptr = (uint8_t *)dstopt;
4504 				*dstptr = ((ipha_t *)rptr)->ipha_ttl;
4505 				dstopt += sizeof (uint8_t);
4506 				udi_size -= toh->len;
4507 			}
4508 
4509 			/* Consumed all of allocated space */
4510 			ASSERT(udi_size == 0);
4511 		}
4512 	} else {
4513 		sin6_t *sin6;
4514 
4515 		/*
4516 		 * Handle both IPv4 and IPv6 packets for IPv6 sockets.
4517 		 *
4518 		 * Normally we only send up the address. If receiving of any
4519 		 * optional receive side information is enabled, we also send
4520 		 * that up as options.
4521 		 * [ Only udp_rput_other() handles packets that contain IP
4522 		 * options so code to account for does not appear immediately
4523 		 * below but elsewhere ]
4524 		 */
4525 		udi_size = sizeof (struct T_unitdata_ind) + sizeof (sin6_t);
4526 
4527 		if (ipp.ipp_fields & (IPPF_HOPOPTS|IPPF_DSTOPTS|IPPF_RTDSTOPTS|
4528 		    IPPF_RTHDR|IPPF_IFINDEX)) {
4529 			if (udp->udp_ipv6_recvhopopts &&
4530 			    (ipp.ipp_fields & IPPF_HOPOPTS)) {
4531 				udi_size += sizeof (struct T_opthdr) +
4532 				    ipp.ipp_hopoptslen;
4533 				UDP_STAT(udp_in_recvhopopts);
4534 			}
4535 			if ((udp->udp_ipv6_recvdstopts ||
4536 				udp->udp_old_ipv6_recvdstopts) &&
4537 			    (ipp.ipp_fields & IPPF_DSTOPTS)) {
4538 				udi_size += sizeof (struct T_opthdr) +
4539 				    ipp.ipp_dstoptslen;
4540 				UDP_STAT(udp_in_recvdstopts);
4541 			}
4542 			if (((udp->udp_ipv6_recvdstopts &&
4543 			    udp->udp_ipv6_recvrthdr &&
4544 			    (ipp.ipp_fields & IPPF_RTHDR)) ||
4545 			    udp->udp_ipv6_recvrthdrdstopts) &&
4546 			    (ipp.ipp_fields & IPPF_RTDSTOPTS)) {
4547 				udi_size += sizeof (struct T_opthdr) +
4548 				    ipp.ipp_rtdstoptslen;
4549 				UDP_STAT(udp_in_recvrtdstopts);
4550 			}
4551 			if (udp->udp_ipv6_recvrthdr &&
4552 			    (ipp.ipp_fields & IPPF_RTHDR)) {
4553 				udi_size += sizeof (struct T_opthdr) +
4554 				    ipp.ipp_rthdrlen;
4555 				UDP_STAT(udp_in_recvrthdr);
4556 			}
4557 			if (udp->udp_ipv6_recvpktinfo &&
4558 			    (ipp.ipp_fields & IPPF_IFINDEX)) {
4559 				udi_size += sizeof (struct T_opthdr) +
4560 				    sizeof (struct in6_pktinfo);
4561 				UDP_STAT(udp_in_recvpktinfo);
4562 			}
4563 
4564 		}
4565 		if (udp->udp_recvucred && (cr = DB_CRED(mp)) != NULL) {
4566 			udi_size += sizeof (struct T_opthdr) + ucredsize;
4567 			cpid = DB_CPID(mp);
4568 			UDP_STAT(udp_in_recvucred);
4569 		}
4570 
4571 		if (udp->udp_ipv6_recvhoplimit) {
4572 			udi_size += sizeof (struct T_opthdr) + sizeof (int);
4573 			UDP_STAT(udp_in_recvhoplimit);
4574 		}
4575 
4576 		if (udp->udp_ipv6_recvtclass) {
4577 			udi_size += sizeof (struct T_opthdr) + sizeof (int);
4578 			UDP_STAT(udp_in_recvtclass);
4579 		}
4580 
4581 		mp1 = allocb(udi_size, BPRI_MED);
4582 		if (mp1 == NULL) {
4583 			freemsg(mp);
4584 			if (options_mp != NULL)
4585 				freeb(options_mp);
4586 			TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4587 				"udp_rput_end: q %p (%S)", q, "allocbfail");
4588 			BUMP_MIB(&udp_mib, udpInErrors);
4589 			return;
4590 		}
4591 		mp1->b_cont = mp;
4592 		mp = mp1;
4593 		mp->b_datap->db_type = M_PROTO;
4594 		tudi = (struct T_unitdata_ind *)mp->b_rptr;
4595 		mp->b_wptr = (uchar_t *)tudi + udi_size;
4596 		tudi->PRIM_type = T_UNITDATA_IND;
4597 		tudi->SRC_length = sizeof (sin6_t);
4598 		tudi->SRC_offset = sizeof (struct T_unitdata_ind);
4599 		tudi->OPT_offset = sizeof (struct T_unitdata_ind) +
4600 		    sizeof (sin6_t);
4601 		udi_size -= (sizeof (struct T_unitdata_ind) + sizeof (sin6_t));
4602 		tudi->OPT_length = udi_size;
4603 		sin6 = (sin6_t *)&tudi[1];
4604 		if (ipversion == IPV4_VERSION) {
4605 			in6_addr_t v6dst;
4606 
4607 			IN6_IPADDR_TO_V4MAPPED(((ipha_t *)rptr)->ipha_src,
4608 			    &sin6->sin6_addr);
4609 			IN6_IPADDR_TO_V4MAPPED(((ipha_t *)rptr)->ipha_dst,
4610 			    &v6dst);
4611 			sin6->sin6_flowinfo = 0;
4612 			sin6->sin6_scope_id = 0;
4613 			sin6->__sin6_src_id = ip_srcid_find_addr(&v6dst,
4614 			    connp->conn_zoneid);
4615 		} else {
4616 			sin6->sin6_addr = ip6h->ip6_src;
4617 			/* No sin6_flowinfo per API */
4618 			sin6->sin6_flowinfo = 0;
4619 			/* For link-scope source pass up scope id */
4620 			if ((ipp.ipp_fields & IPPF_IFINDEX) &&
4621 			    IN6_IS_ADDR_LINKSCOPE(&ip6h->ip6_src))
4622 				sin6->sin6_scope_id = ipp.ipp_ifindex;
4623 			else
4624 				sin6->sin6_scope_id = 0;
4625 			sin6->__sin6_src_id = ip_srcid_find_addr(
4626 			    &ip6h->ip6_dst, connp->conn_zoneid);
4627 		}
4628 		sin6->sin6_port = udpha->uha_src_port;
4629 		sin6->sin6_family = udp->udp_family;
4630 
4631 		if (udi_size != 0) {
4632 			uchar_t *dstopt;
4633 
4634 			dstopt = (uchar_t *)&sin6[1];
4635 			if (udp->udp_ipv6_recvpktinfo &&
4636 			    (ipp.ipp_fields & IPPF_IFINDEX)) {
4637 				struct T_opthdr *toh;
4638 				struct in6_pktinfo *pkti;
4639 
4640 				toh = (struct T_opthdr *)dstopt;
4641 				toh->level = IPPROTO_IPV6;
4642 				toh->name = IPV6_PKTINFO;
4643 				toh->len = sizeof (struct T_opthdr) +
4644 				    sizeof (*pkti);
4645 				toh->status = 0;
4646 				dstopt += sizeof (struct T_opthdr);
4647 				pkti = (struct in6_pktinfo *)dstopt;
4648 				if (ipversion == IPV6_VERSION)
4649 					pkti->ipi6_addr = ip6h->ip6_dst;
4650 				else
4651 					IN6_IPADDR_TO_V4MAPPED(
4652 						((ipha_t *)rptr)->ipha_dst,
4653 						    &pkti->ipi6_addr);
4654 				pkti->ipi6_ifindex = ipp.ipp_ifindex;
4655 				dstopt += sizeof (*pkti);
4656 				udi_size -= toh->len;
4657 			}
4658 			if (udp->udp_ipv6_recvhoplimit) {
4659 				struct T_opthdr *toh;
4660 
4661 				toh = (struct T_opthdr *)dstopt;
4662 				toh->level = IPPROTO_IPV6;
4663 				toh->name = IPV6_HOPLIMIT;
4664 				toh->len = sizeof (struct T_opthdr) +
4665 				    sizeof (uint_t);
4666 				toh->status = 0;
4667 				dstopt += sizeof (struct T_opthdr);
4668 				if (ipversion == IPV6_VERSION)
4669 					*(uint_t *)dstopt = ip6h->ip6_hops;
4670 				else
4671 					*(uint_t *)dstopt =
4672 					    ((ipha_t *)rptr)->ipha_ttl;
4673 				dstopt += sizeof (uint_t);
4674 				udi_size -= toh->len;
4675 			}
4676 			if (udp->udp_ipv6_recvtclass) {
4677 				struct T_opthdr *toh;
4678 
4679 				toh = (struct T_opthdr *)dstopt;
4680 				toh->level = IPPROTO_IPV6;
4681 				toh->name = IPV6_TCLASS;
4682 				toh->len = sizeof (struct T_opthdr) +
4683 				    sizeof (uint_t);
4684 				toh->status = 0;
4685 				dstopt += sizeof (struct T_opthdr);
4686 				if (ipversion == IPV6_VERSION) {
4687 					*(uint_t *)dstopt =
4688 					IPV6_FLOW_TCLASS(ip6h->ip6_flow);
4689 				} else {
4690 					ipha_t *ipha = (ipha_t *)rptr;
4691 					*(uint_t *)dstopt =
4692 					    ipha->ipha_type_of_service;
4693 				}
4694 				dstopt += sizeof (uint_t);
4695 				udi_size -= toh->len;
4696 			}
4697 			if (udp->udp_ipv6_recvhopopts &&
4698 			    (ipp.ipp_fields & IPPF_HOPOPTS)) {
4699 				struct T_opthdr *toh;
4700 
4701 				toh = (struct T_opthdr *)dstopt;
4702 				toh->level = IPPROTO_IPV6;
4703 				toh->name = IPV6_HOPOPTS;
4704 				toh->len = sizeof (struct T_opthdr) +
4705 				    ipp.ipp_hopoptslen;
4706 				toh->status = 0;
4707 				dstopt += sizeof (struct T_opthdr);
4708 				bcopy(ipp.ipp_hopopts, dstopt,
4709 				    ipp.ipp_hopoptslen);
4710 				dstopt += ipp.ipp_hopoptslen;
4711 				udi_size -= toh->len;
4712 			}
4713 			if (udp->udp_ipv6_recvdstopts &&
4714 			    udp->udp_ipv6_recvrthdr &&
4715 			    (ipp.ipp_fields & IPPF_RTHDR) &&
4716 			    (ipp.ipp_fields & IPPF_RTDSTOPTS)) {
4717 				struct T_opthdr *toh;
4718 
4719 				toh = (struct T_opthdr *)dstopt;
4720 				toh->level = IPPROTO_IPV6;
4721 				toh->name = IPV6_DSTOPTS;
4722 				toh->len = sizeof (struct T_opthdr) +
4723 				    ipp.ipp_rtdstoptslen;
4724 				toh->status = 0;
4725 				dstopt += sizeof (struct T_opthdr);
4726 				bcopy(ipp.ipp_rtdstopts, dstopt,
4727 				    ipp.ipp_rtdstoptslen);
4728 				dstopt += ipp.ipp_rtdstoptslen;
4729 				udi_size -= toh->len;
4730 			}
4731 			if (udp->udp_ipv6_recvrthdr &&
4732 			    (ipp.ipp_fields & IPPF_RTHDR)) {
4733 				struct T_opthdr *toh;
4734 
4735 				toh = (struct T_opthdr *)dstopt;
4736 				toh->level = IPPROTO_IPV6;
4737 				toh->name = IPV6_RTHDR;
4738 				toh->len = sizeof (struct T_opthdr) +
4739 				    ipp.ipp_rthdrlen;
4740 				toh->status = 0;
4741 				dstopt += sizeof (struct T_opthdr);
4742 				bcopy(ipp.ipp_rthdr, dstopt, ipp.ipp_rthdrlen);
4743 				dstopt += ipp.ipp_rthdrlen;
4744 				udi_size -= toh->len;
4745 			}
4746 			if (udp->udp_ipv6_recvdstopts &&
4747 			    (ipp.ipp_fields & IPPF_DSTOPTS)) {
4748 				struct T_opthdr *toh;
4749 
4750 				toh = (struct T_opthdr *)dstopt;
4751 				toh->level = IPPROTO_IPV6;
4752 				toh->name = IPV6_DSTOPTS;
4753 				toh->len = sizeof (struct T_opthdr) +
4754 				    ipp.ipp_dstoptslen;
4755 				toh->status = 0;
4756 				dstopt += sizeof (struct T_opthdr);
4757 				bcopy(ipp.ipp_dstopts, dstopt,
4758 				    ipp.ipp_dstoptslen);
4759 				dstopt += ipp.ipp_dstoptslen;
4760 				udi_size -= toh->len;
4761 			}
4762 
4763 			if (cr != NULL) {
4764 				struct T_opthdr *toh;
4765 
4766 				toh = (struct T_opthdr *)dstopt;
4767 				toh->level = SOL_SOCKET;
4768 				toh->name = SCM_UCRED;
4769 				toh->len = sizeof (struct T_opthdr) + ucredsize;
4770 				toh->status = 0;
4771 				(void) cred2ucred(cr, cpid, &toh[1]);
4772 				dstopt += toh->len;
4773 				udi_size -= toh->len;
4774 			}
4775 			/* Consumed all of allocated space */
4776 			ASSERT(udi_size == 0);
4777 		}
4778 #undef	sin6
4779 		/* No IP_RECVDSTADDR for IPv6. */
4780 	}
4781 
4782 	BUMP_MIB(&udp_mib, udpInDatagrams);
4783 	TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4784 		"udp_rput_end: q %p (%S)", q, "end");
4785 	if (options_mp != NULL)
4786 		freeb(options_mp);
4787 
4788 	if (udp->udp_direct_sockfs) {
4789 		/*
4790 		 * There is nothing above us except for the stream head;
4791 		 * use the read-side synchronous stream interface in
4792 		 * order to reduce the time spent in interrupt thread.
4793 		 */
4794 		ASSERT(udp->udp_issocket);
4795 		udp_rcv_enqueue(UDP_RD(q), udp, mp, mp_len);
4796 	} else {
4797 		/*
4798 		 * Use regular STREAMS interface to pass data upstream
4799 		 * if this is not a socket endpoint, or if we have
4800 		 * switched over to the slow mode due to sockmod being
4801 		 * popped or a module being pushed on top of us.
4802 		 */
4803 		putnext(UDP_RD(q), mp);
4804 	}
4805 	return;
4806 
4807 tossit:
4808 	freemsg(mp);
4809 	if (options_mp != NULL)
4810 		freeb(options_mp);
4811 	BUMP_MIB(&udp_mib, udpInErrors);
4812 }
4813 
4814 void
4815 udp_conn_recv(conn_t *connp, mblk_t *mp)
4816 {
4817 	_UDP_ENTER(connp, mp, udp_input_wrapper, SQTAG_UDP_FANOUT);
4818 }
4819 
4820 /* ARGSUSED */
4821 static void
4822 udp_input_wrapper(void *arg, mblk_t *mp, void *arg2)
4823 {
4824 	udp_input((conn_t *)arg, mp);
4825 	_UDP_EXIT((conn_t *)arg);
4826 }
4827 
4828 /*
4829  * Process non-M_DATA messages as well as M_DATA messages that requires
4830  * modifications to udp_ip_rcv_options i.e. IPv4 packets with IP options.
4831  */
4832 static void
4833 udp_rput_other(queue_t *q, mblk_t *mp)
4834 {
4835 	struct T_unitdata_ind	*tudi;
4836 	mblk_t			*mp1;
4837 	uchar_t			*rptr;
4838 	uchar_t			*new_rptr;
4839 	int			hdr_length;
4840 	int			udi_size;	/* Size of T_unitdata_ind */
4841 	int			opt_len;	/* Length of IP options */
4842 	sin_t			*sin;
4843 	struct T_error_ack	*tea;
4844 	mblk_t			*options_mp = NULL;
4845 	in_pktinfo_t		*pinfo;
4846 	boolean_t		recv_on = B_FALSE;
4847 	cred_t			*cr = NULL;
4848 	udp_t			*udp = Q_TO_UDP(q);
4849 	pid_t			cpid;
4850 
4851 	TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_START,
4852 	    "udp_rput_other: q %p mp %p", q, mp);
4853 
4854 	ASSERT(OK_32PTR(mp->b_rptr));
4855 	rptr = mp->b_rptr;
4856 
4857 	switch (mp->b_datap->db_type) {
4858 	case M_CTL:
4859 		/*
4860 		 * We are here only if IP_RECVSLLA and/or IP_RECVIF are set
4861 		 */
4862 		recv_on = B_TRUE;
4863 		options_mp = mp;
4864 		pinfo = (in_pktinfo_t *)options_mp->b_rptr;
4865 
4866 		/*
4867 		 * The actual data is in mp->b_cont
4868 		 */
4869 		mp = mp->b_cont;
4870 		ASSERT(OK_32PTR(mp->b_rptr));
4871 		rptr = mp->b_rptr;
4872 		break;
4873 	case M_DATA:
4874 		/*
4875 		 * M_DATA messages contain IPv4 datagrams.  They are handled
4876 		 * after this switch.
4877 		 */
4878 		break;
4879 	case M_PROTO:
4880 	case M_PCPROTO:
4881 		/* M_PROTO messages contain some type of TPI message. */
4882 		ASSERT((uintptr_t)(mp->b_wptr - rptr) <= (uintptr_t)INT_MAX);
4883 		if (mp->b_wptr - rptr < sizeof (t_scalar_t)) {
4884 			freemsg(mp);
4885 			TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4886 			    "udp_rput_other_end: q %p (%S)", q, "protoshort");
4887 			return;
4888 		}
4889 		tea = (struct T_error_ack *)rptr;
4890 
4891 		switch (tea->PRIM_type) {
4892 		case T_ERROR_ACK:
4893 			switch (tea->ERROR_prim) {
4894 			case O_T_BIND_REQ:
4895 			case T_BIND_REQ: {
4896 				/*
4897 				 * If our O_T_BIND_REQ/T_BIND_REQ fails,
4898 				 * clear out the associated port and source
4899 				 * address before passing the message
4900 				 * upstream. If this was caused by a T_CONN_REQ
4901 				 * revert back to bound state.
4902 				 */
4903 				udp_fanout_t	*udpf;
4904 
4905 				udpf = &udp_bind_fanout[
4906 				    UDP_BIND_HASH(udp->udp_port)];
4907 				mutex_enter(&udpf->uf_lock);
4908 				if (udp->udp_state == TS_DATA_XFER) {
4909 					/* Connect failed */
4910 					tea->ERROR_prim = T_CONN_REQ;
4911 					/* Revert back to the bound source */
4912 					udp->udp_v6src = udp->udp_bound_v6src;
4913 					udp->udp_state = TS_IDLE;
4914 					mutex_exit(&udpf->uf_lock);
4915 					if (udp->udp_family == AF_INET6)
4916 						(void) udp_build_hdrs(q, udp);
4917 					break;
4918 				}
4919 
4920 				if (udp->udp_discon_pending) {
4921 					tea->ERROR_prim = T_DISCON_REQ;
4922 					udp->udp_discon_pending = 0;
4923 				}
4924 				V6_SET_ZERO(udp->udp_v6src);
4925 				V6_SET_ZERO(udp->udp_bound_v6src);
4926 				udp->udp_state = TS_UNBND;
4927 				udp_bind_hash_remove(udp, B_TRUE);
4928 				udp->udp_port = 0;
4929 				mutex_exit(&udpf->uf_lock);
4930 				if (udp->udp_family == AF_INET6)
4931 					(void) udp_build_hdrs(q, udp);
4932 				break;
4933 			}
4934 			default:
4935 				break;
4936 			}
4937 			break;
4938 		case T_BIND_ACK:
4939 			udp_rput_bind_ack(q, mp);
4940 			return;
4941 
4942 		case T_OPTMGMT_ACK:
4943 		case T_OK_ACK:
4944 			break;
4945 		default:
4946 			freemsg(mp);
4947 			return;
4948 		}
4949 		putnext(UDP_RD(q), mp);
4950 		return;
4951 	}
4952 
4953 	/*
4954 	 * This is the inbound data path.
4955 	 * First, we make sure the data contains both IP and UDP headers.
4956 	 *
4957 	 * This handle IPv4 packets for only AF_INET sockets.
4958 	 * AF_INET6 sockets can never access udp_ip_rcv_options thus there
4959 	 * is no need saving the options.
4960 	 */
4961 	ASSERT(IPH_HDR_VERSION((ipha_t *)rptr) == IPV4_VERSION);
4962 	hdr_length = IPH_HDR_LENGTH(rptr) + UDPH_SIZE;
4963 	if (mp->b_wptr - rptr < hdr_length) {
4964 		if (!pullupmsg(mp, hdr_length)) {
4965 			freemsg(mp);
4966 			if (options_mp != NULL)
4967 				freeb(options_mp);
4968 			BUMP_MIB(&udp_mib, udpInErrors);
4969 			TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
4970 			    "udp_rput_other_end: q %p (%S)", q, "hdrshort");
4971 			BUMP_MIB(&udp_mib, udpInErrors);
4972 			return;
4973 		}
4974 		rptr = mp->b_rptr;
4975 	}
4976 	/* Walk past the headers. */
4977 	new_rptr = rptr + hdr_length;
4978 	if (!udp->udp_rcvhdr)
4979 		mp->b_rptr = new_rptr;
4980 
4981 	/* Save the options if any */
4982 	opt_len = hdr_length - (IP_SIMPLE_HDR_LENGTH + UDPH_SIZE);
4983 	if (opt_len > 0) {
4984 		if (opt_len > udp->udp_ip_rcv_options_len) {
4985 			if (udp->udp_ip_rcv_options_len)
4986 				mi_free((char *)udp->udp_ip_rcv_options);
4987 			udp->udp_ip_rcv_options_len = 0;
4988 			udp->udp_ip_rcv_options =
4989 			    (uchar_t *)mi_alloc(opt_len, BPRI_HI);
4990 			if (udp->udp_ip_rcv_options)
4991 				udp->udp_ip_rcv_options_len = opt_len;
4992 		}
4993 		if (udp->udp_ip_rcv_options_len) {
4994 			bcopy(rptr + IP_SIMPLE_HDR_LENGTH,
4995 			    udp->udp_ip_rcv_options, opt_len);
4996 			/* Adjust length if we are resusing the space */
4997 			udp->udp_ip_rcv_options_len = opt_len;
4998 		}
4999 	} else if (udp->udp_ip_rcv_options_len) {
5000 		mi_free((char *)udp->udp_ip_rcv_options);
5001 		udp->udp_ip_rcv_options = NULL;
5002 		udp->udp_ip_rcv_options_len = 0;
5003 	}
5004 
5005 	/*
5006 	 * Normally only send up the address.
5007 	 * If IP_RECVDSTADDR is set we include the destination IP
5008 	 * address as an option. With IP_RECVOPTS we include all
5009 	 * the IP options.
5010 	 */
5011 	udi_size = sizeof (struct T_unitdata_ind) + sizeof (sin_t);
5012 	if (udp->udp_recvdstaddr) {
5013 		udi_size += sizeof (struct T_opthdr) + sizeof (struct in_addr);
5014 		UDP_STAT(udp_in_recvdstaddr);
5015 	}
5016 	if (udp->udp_recvopts && opt_len > 0) {
5017 		udi_size += sizeof (struct T_opthdr) + opt_len;
5018 		UDP_STAT(udp_in_recvopts);
5019 	}
5020 
5021 	/*
5022 	 * If the IP_RECVSLLA or the IP_RECVIF is set then allocate
5023 	 * space accordingly
5024 	 */
5025 	if (udp->udp_recvif && recv_on &&
5026 	    (pinfo->in_pkt_flags & IPF_RECVIF)) {
5027 		udi_size += sizeof (struct T_opthdr) + sizeof (uint_t);
5028 		UDP_STAT(udp_in_recvif);
5029 	}
5030 
5031 	if (udp->udp_recvslla && recv_on &&
5032 	    (pinfo->in_pkt_flags & IPF_RECVSLLA)) {
5033 		udi_size += sizeof (struct T_opthdr) +
5034 		    sizeof (struct sockaddr_dl);
5035 		UDP_STAT(udp_in_recvslla);
5036 	}
5037 
5038 	if (udp->udp_recvucred && (cr = DB_CRED(mp)) != NULL) {
5039 		udi_size += sizeof (struct T_opthdr) + ucredsize;
5040 		cpid = DB_CPID(mp);
5041 		UDP_STAT(udp_in_recvucred);
5042 	}
5043 	/*
5044 	 * If IP_RECVTTL is set allocate the appropriate sized buffer
5045 	 */
5046 	if (udp->udp_recvttl) {
5047 		udi_size += sizeof (struct T_opthdr) + sizeof (uint8_t);
5048 		UDP_STAT(udp_in_recvttl);
5049 	}
5050 
5051 	/* Allocate a message block for the T_UNITDATA_IND structure. */
5052 	mp1 = allocb(udi_size, BPRI_MED);
5053 	if (mp1 == NULL) {
5054 		freemsg(mp);
5055 		if (options_mp != NULL)
5056 			freeb(options_mp);
5057 		TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
5058 			"udp_rput_other_end: q %p (%S)", q, "allocbfail");
5059 		BUMP_MIB(&udp_mib, udpInErrors);
5060 		return;
5061 	}
5062 	mp1->b_cont = mp;
5063 	mp = mp1;
5064 	mp->b_datap->db_type = M_PROTO;
5065 	tudi = (struct T_unitdata_ind *)mp->b_rptr;
5066 	mp->b_wptr = (uchar_t *)tudi + udi_size;
5067 	tudi->PRIM_type = T_UNITDATA_IND;
5068 	tudi->SRC_length = sizeof (sin_t);
5069 	tudi->SRC_offset = sizeof (struct T_unitdata_ind);
5070 	tudi->OPT_offset = sizeof (struct T_unitdata_ind) + sizeof (sin_t);
5071 	udi_size -= (sizeof (struct T_unitdata_ind) + sizeof (sin_t));
5072 	tudi->OPT_length = udi_size;
5073 
5074 	sin = (sin_t *)&tudi[1];
5075 	sin->sin_addr.s_addr = ((ipha_t *)rptr)->ipha_src;
5076 	sin->sin_port =	((in_port_t *)
5077 	    new_rptr)[-(UDPH_SIZE/sizeof (in_port_t))];
5078 	sin->sin_family = AF_INET;
5079 	*(uint32_t *)&sin->sin_zero[0] = 0;
5080 	*(uint32_t *)&sin->sin_zero[4] = 0;
5081 
5082 	/*
5083 	 * Add options if IP_RECVDSTADDR, IP_RECVIF, IP_RECVSLLA or
5084 	 * IP_RECVTTL has been set.
5085 	 */
5086 	if (udi_size != 0) {
5087 		/*
5088 		 * Copy in destination address before options to avoid any
5089 		 * padding issues.
5090 		 */
5091 		char *dstopt;
5092 
5093 		dstopt = (char *)&sin[1];
5094 		if (udp->udp_recvdstaddr) {
5095 			struct T_opthdr *toh;
5096 			ipaddr_t *dstptr;
5097 
5098 			toh = (struct T_opthdr *)dstopt;
5099 			toh->level = IPPROTO_IP;
5100 			toh->name = IP_RECVDSTADDR;
5101 			toh->len = sizeof (struct T_opthdr) + sizeof (ipaddr_t);
5102 			toh->status = 0;
5103 			dstopt += sizeof (struct T_opthdr);
5104 			dstptr = (ipaddr_t *)dstopt;
5105 			*dstptr = (((ipaddr_t *)rptr)[4]);
5106 			dstopt += sizeof (ipaddr_t);
5107 			udi_size -= toh->len;
5108 		}
5109 		if (udp->udp_recvopts && udi_size != 0) {
5110 			struct T_opthdr *toh;
5111 
5112 			toh = (struct T_opthdr *)dstopt;
5113 			toh->level = IPPROTO_IP;
5114 			toh->name = IP_RECVOPTS;
5115 			toh->len = sizeof (struct T_opthdr) + opt_len;
5116 			toh->status = 0;
5117 			dstopt += sizeof (struct T_opthdr);
5118 			bcopy(rptr + IP_SIMPLE_HDR_LENGTH, dstopt, opt_len);
5119 			dstopt += opt_len;
5120 			udi_size -= toh->len;
5121 		}
5122 
5123 		if (udp->udp_recvslla && recv_on &&
5124 		    (pinfo->in_pkt_flags & IPF_RECVSLLA)) {
5125 
5126 			struct T_opthdr *toh;
5127 			struct sockaddr_dl	*dstptr;
5128 
5129 			toh = (struct T_opthdr *)dstopt;
5130 			toh->level = IPPROTO_IP;
5131 			toh->name = IP_RECVSLLA;
5132 			toh->len = sizeof (struct T_opthdr) +
5133 			    sizeof (struct sockaddr_dl);
5134 			toh->status = 0;
5135 			dstopt += sizeof (struct T_opthdr);
5136 			dstptr = (struct sockaddr_dl *)dstopt;
5137 			bcopy(&pinfo->in_pkt_slla, dstptr,
5138 			    sizeof (struct sockaddr_dl));
5139 			dstopt += sizeof (struct sockaddr_dl);
5140 			udi_size -= toh->len;
5141 		}
5142 
5143 		if (udp->udp_recvif && recv_on &&
5144 		    (pinfo->in_pkt_flags & IPF_RECVIF)) {
5145 
5146 			struct T_opthdr *toh;
5147 			uint_t		*dstptr;
5148 
5149 			toh = (struct T_opthdr *)dstopt;
5150 			toh->level = IPPROTO_IP;
5151 			toh->name = IP_RECVIF;
5152 			toh->len = sizeof (struct T_opthdr) +
5153 			    sizeof (uint_t);
5154 			toh->status = 0;
5155 			dstopt += sizeof (struct T_opthdr);
5156 			dstptr = (uint_t *)dstopt;
5157 			*dstptr = pinfo->in_pkt_ifindex;
5158 			dstopt += sizeof (uint_t);
5159 			udi_size -= toh->len;
5160 		}
5161 
5162 		if (cr != NULL) {
5163 			struct T_opthdr *toh;
5164 
5165 			toh = (struct T_opthdr *)dstopt;
5166 			toh->level = SOL_SOCKET;
5167 			toh->name = SCM_UCRED;
5168 			toh->len = sizeof (struct T_opthdr) + ucredsize;
5169 			toh->status = 0;
5170 			(void) cred2ucred(cr, cpid, &toh[1]);
5171 			dstopt += toh->len;
5172 			udi_size -= toh->len;
5173 		}
5174 
5175 		if (udp->udp_recvttl) {
5176 			struct	T_opthdr *toh;
5177 			uint8_t	*dstptr;
5178 
5179 			toh = (struct T_opthdr *)dstopt;
5180 			toh->level = IPPROTO_IP;
5181 			toh->name = IP_RECVTTL;
5182 			toh->len = sizeof (struct T_opthdr) +
5183 			    sizeof (uint8_t);
5184 			toh->status = 0;
5185 			dstopt += sizeof (struct T_opthdr);
5186 			dstptr = (uint8_t *)dstopt;
5187 			*dstptr = ((ipha_t *)rptr)->ipha_ttl;
5188 			dstopt += sizeof (uint8_t);
5189 			udi_size -= toh->len;
5190 		}
5191 
5192 		ASSERT(udi_size == 0);	/* "Consumed" all of allocated space */
5193 	}
5194 	BUMP_MIB(&udp_mib, udpInDatagrams);
5195 	TRACE_2(TR_FAC_UDP, TR_UDP_RPUT_END,
5196 	    "udp_rput_other_end: q %p (%S)", q, "end");
5197 	if (options_mp != NULL)
5198 		freeb(options_mp);
5199 
5200 	if (udp->udp_direct_sockfs) {
5201 		/*
5202 		 * There is nothing above us except for the stream head;
5203 		 * use the read-side synchronous stream interface in
5204 		 * order to reduce the time spent in interrupt thread.
5205 		 */
5206 		ASSERT(udp->udp_issocket);
5207 		udp_rcv_enqueue(UDP_RD(q), udp, mp, msgdsize(mp));
5208 	} else {
5209 		/*
5210 		 * Use regular STREAMS interface to pass data upstream
5211 		 * if this is not a socket endpoint, or if we have
5212 		 * switched over to the slow mode due to sockmod being
5213 		 * popped or a module being pushed on top of us.
5214 		 */
5215 		putnext(UDP_RD(q), mp);
5216 	}
5217 }
5218 
5219 /* ARGSUSED */
5220 static void
5221 udp_rput_other_wrapper(void *arg, mblk_t *mp, void *arg2)
5222 {
5223 	conn_t *connp = arg;
5224 
5225 	udp_rput_other(connp->conn_rq, mp);
5226 	udp_exit(connp);
5227 }
5228 
5229 /*
5230  * Process a T_BIND_ACK
5231  */
5232 static void
5233 udp_rput_bind_ack(queue_t *q, mblk_t *mp)
5234 {
5235 	udp_t	*udp = Q_TO_UDP(q);
5236 	mblk_t	*mp1;
5237 	ire_t	*ire;
5238 	struct T_bind_ack *tba;
5239 	uchar_t *addrp;
5240 	ipa_conn_t	*ac;
5241 	ipa6_conn_t	*ac6;
5242 
5243 	if (udp->udp_discon_pending)
5244 		udp->udp_discon_pending = 0;
5245 
5246 	/*
5247 	 * If a broadcast/multicast address was bound set
5248 	 * the source address to 0.
5249 	 * This ensures no datagrams with broadcast address
5250 	 * as source address are emitted (which would violate
5251 	 * RFC1122 - Hosts requirements)
5252 	 *
5253 	 * Note that when connecting the returned IRE is
5254 	 * for the destination address and we only perform
5255 	 * the broadcast check for the source address (it
5256 	 * is OK to connect to a broadcast/multicast address.)
5257 	 */
5258 	mp1 = mp->b_cont;
5259 	if (mp1 != NULL && mp1->b_datap->db_type == IRE_DB_TYPE) {
5260 		ire = (ire_t *)mp1->b_rptr;
5261 
5262 		/*
5263 		 * Note: we get IRE_BROADCAST for IPv6 to "mark" a multicast
5264 		 * local address.
5265 		 */
5266 		if (ire->ire_type == IRE_BROADCAST &&
5267 		    udp->udp_state != TS_DATA_XFER) {
5268 			/* This was just a local bind to a broadcast addr */
5269 			V6_SET_ZERO(udp->udp_v6src);
5270 			if (udp->udp_family == AF_INET6)
5271 				(void) udp_build_hdrs(q, udp);
5272 		} else if (V6_OR_V4_INADDR_ANY(udp->udp_v6src)) {
5273 			/*
5274 			 * Local address not yet set - pick it from the
5275 			 * T_bind_ack
5276 			 */
5277 			tba = (struct T_bind_ack *)mp->b_rptr;
5278 			addrp = &mp->b_rptr[tba->ADDR_offset];
5279 			switch (udp->udp_family) {
5280 			case AF_INET:
5281 				if (tba->ADDR_length == sizeof (ipa_conn_t)) {
5282 					ac = (ipa_conn_t *)addrp;
5283 				} else {
5284 					ASSERT(tba->ADDR_length ==
5285 					    sizeof (ipa_conn_x_t));
5286 					ac = &((ipa_conn_x_t *)addrp)->acx_conn;
5287 				}
5288 				IN6_IPADDR_TO_V4MAPPED(ac->ac_laddr,
5289 				    &udp->udp_v6src);
5290 				break;
5291 			case AF_INET6:
5292 				if (tba->ADDR_length == sizeof (ipa6_conn_t)) {
5293 					ac6 = (ipa6_conn_t *)addrp;
5294 				} else {
5295 					ASSERT(tba->ADDR_length ==
5296 					    sizeof (ipa6_conn_x_t));
5297 					ac6 = &((ipa6_conn_x_t *)
5298 					    addrp)->ac6x_conn;
5299 				}
5300 				udp->udp_v6src = ac6->ac6_laddr;
5301 				(void) udp_build_hdrs(q, udp);
5302 				break;
5303 			}
5304 		}
5305 		mp1 = mp1->b_cont;
5306 	}
5307 	/*
5308 	 * Look for one or more appended ACK message added by
5309 	 * udp_connect or udp_disconnect.
5310 	 * If none found just send up the T_BIND_ACK.
5311 	 * udp_connect has appended a T_OK_ACK and a T_CONN_CON.
5312 	 * udp_disconnect has appended a T_OK_ACK.
5313 	 */
5314 	if (mp1 != NULL) {
5315 		if (mp->b_cont == mp1)
5316 			mp->b_cont = NULL;
5317 		else {
5318 			ASSERT(mp->b_cont->b_cont == mp1);
5319 			mp->b_cont->b_cont = NULL;
5320 		}
5321 		freemsg(mp);
5322 		mp = mp1;
5323 		while (mp != NULL) {
5324 			mp1 = mp->b_cont;
5325 			mp->b_cont = NULL;
5326 			putnext(UDP_RD(q), mp);
5327 			mp = mp1;
5328 		}
5329 		return;
5330 	}
5331 	freemsg(mp->b_cont);
5332 	mp->b_cont = NULL;
5333 	putnext(UDP_RD(q), mp);
5334 }
5335 
5336 /*
5337  * return SNMP stuff in buffer in mpdata
5338  */
5339 int
5340 udp_snmp_get(queue_t *q, mblk_t *mpctl)
5341 {
5342 	mblk_t			*mpdata;
5343 	mblk_t			*mp_conn_ctl;
5344 	mblk_t			*mp6_conn_ctl;
5345 	mblk_t			*mp_conn_data;
5346 	mblk_t			*mp6_conn_data;
5347 	mblk_t			*mp_conn_tail = NULL;
5348 	mblk_t			*mp6_conn_tail = NULL;
5349 	struct opthdr		*optp;
5350 	mib2_udpEntry_t		ude;
5351 	mib2_udp6Entry_t	ude6;
5352 	int			state;
5353 	zoneid_t		zoneid;
5354 	int			i;
5355 	connf_t			*connfp;
5356 	conn_t			*connp = Q_TO_CONN(q);
5357 	udp_t			*udp = connp->conn_udp;
5358 
5359 	if (mpctl == NULL ||
5360 	    (mpdata = mpctl->b_cont) == NULL ||
5361 	    (mp_conn_ctl = copymsg(mpctl)) == NULL ||
5362 	    (mp6_conn_ctl = copymsg(mpctl)) == NULL) {
5363 		freemsg(mp_conn_ctl);
5364 		return (0);
5365 	}
5366 
5367 	mp_conn_data = mp_conn_ctl->b_cont;
5368 	mp6_conn_data = mp6_conn_ctl->b_cont;
5369 
5370 	zoneid = connp->conn_zoneid;
5371 
5372 	/* fixed length structure for IPv4 and IPv6 counters */
5373 	SET_MIB(udp_mib.udpEntrySize, sizeof (mib2_udpEntry_t));
5374 	SET_MIB(udp_mib.udp6EntrySize, sizeof (mib2_udp6Entry_t));
5375 	optp = (struct opthdr *)&mpctl->b_rptr[sizeof (struct T_optmgmt_ack)];
5376 	optp->level = MIB2_UDP;
5377 	optp->name = 0;
5378 	(void) snmp_append_data(mpdata, (char *)&udp_mib, sizeof (udp_mib));
5379 	optp->len = msgdsize(mpdata);
5380 	qreply(q, mpctl);
5381 
5382 	for (i = 0; i < CONN_G_HASH_SIZE; i++) {
5383 		connfp = &ipcl_globalhash_fanout[i];
5384 		connp = NULL;
5385 
5386 		while ((connp = ipcl_get_next_conn(connfp, connp,
5387 		    IPCL_UDP))) {
5388 			udp = connp->conn_udp;
5389 			if (zoneid != connp->conn_zoneid)
5390 				continue;
5391 
5392 			/*
5393 			 * Note that the port numbers are sent in
5394 			 * host byte order
5395 			 */
5396 
5397 			if (udp->udp_state == TS_UNBND)
5398 				state = MIB2_UDP_unbound;
5399 			else if (udp->udp_state == TS_IDLE)
5400 				state = MIB2_UDP_idle;
5401 			else if (udp->udp_state == TS_DATA_XFER)
5402 				state = MIB2_UDP_connected;
5403 			else
5404 				state = MIB2_UDP_unknown;
5405 
5406 			/*
5407 			 * Create an IPv4 table entry for IPv4 entries and also
5408 			 * any IPv6 entries which are bound to in6addr_any
5409 			 * (i.e. anything a IPv4 peer could connect/send to).
5410 			 */
5411 			if (udp->udp_ipversion == IPV4_VERSION ||
5412 			    (udp->udp_state <= TS_IDLE &&
5413 			    IN6_IS_ADDR_UNSPECIFIED(&udp->udp_v6src))) {
5414 				ude.udpEntryInfo.ue_state = state;
5415 				/*
5416 				 * If in6addr_any this will set it to
5417 				 * INADDR_ANY
5418 				 */
5419 				ude.udpLocalAddress =
5420 				    V4_PART_OF_V6(udp->udp_v6src);
5421 				ude.udpLocalPort = ntohs(udp->udp_port);
5422 				if (udp->udp_state == TS_DATA_XFER) {
5423 					/*
5424 					 * Can potentially get here for
5425 					 * v6 socket if another process
5426 					 * (say, ping) has just done a
5427 					 * sendto(), changing the state
5428 					 * from the TS_IDLE above to
5429 					 * TS_DATA_XFER by the time we hit
5430 					 * this part of the code.
5431 					 */
5432 					ude.udpEntryInfo.ue_RemoteAddress =
5433 					    V4_PART_OF_V6(udp->udp_v6dst);
5434 					ude.udpEntryInfo.ue_RemotePort =
5435 					    ntohs(udp->udp_dstport);
5436 				} else {
5437 					ude.udpEntryInfo.ue_RemoteAddress = 0;
5438 					ude.udpEntryInfo.ue_RemotePort = 0;
5439 				}
5440 				(void) snmp_append_data2(mp_conn_data,
5441 				    &mp_conn_tail, (char *)&ude, sizeof (ude));
5442 			}
5443 			if (udp->udp_ipversion == IPV6_VERSION) {
5444 				ude6.udp6EntryInfo.ue_state  = state;
5445 				ude6.udp6LocalAddress = udp->udp_v6src;
5446 				ude6.udp6LocalPort = ntohs(udp->udp_port);
5447 				ude6.udp6IfIndex = udp->udp_bound_if;
5448 				if (udp->udp_state == TS_DATA_XFER) {
5449 					ude6.udp6EntryInfo.ue_RemoteAddress =
5450 					    udp->udp_v6dst;
5451 					ude6.udp6EntryInfo.ue_RemotePort =
5452 					    ntohs(udp->udp_dstport);
5453 				} else {
5454 					ude6.udp6EntryInfo.ue_RemoteAddress =
5455 					    sin6_null.sin6_addr;
5456 					ude6.udp6EntryInfo.ue_RemotePort = 0;
5457 				}
5458 				(void) snmp_append_data2(mp6_conn_data,
5459 				    &mp6_conn_tail, (char *)&ude6,
5460 				    sizeof (ude6));
5461 			}
5462 		}
5463 	}
5464 
5465 	/* IPv4 UDP endpoints */
5466 	optp = (struct opthdr *)&mp_conn_ctl->b_rptr[
5467 	    sizeof (struct T_optmgmt_ack)];
5468 	optp->level = MIB2_UDP;
5469 	optp->name = MIB2_UDP_ENTRY;
5470 	optp->len = msgdsize(mp_conn_data);
5471 	qreply(q, mp_conn_ctl);
5472 
5473 	/* IPv6 UDP endpoints */
5474 	optp = (struct opthdr *)&mp6_conn_ctl->b_rptr[
5475 	    sizeof (struct T_optmgmt_ack)];
5476 	optp->level = MIB2_UDP6;
5477 	optp->name = MIB2_UDP6_ENTRY;
5478 	optp->len = msgdsize(mp6_conn_data);
5479 	qreply(q, mp6_conn_ctl);
5480 
5481 	return (1);
5482 }
5483 
5484 /*
5485  * Return 0 if invalid set request, 1 otherwise, including non-udp requests.
5486  * NOTE: Per MIB-II, UDP has no writable data.
5487  * TODO:  If this ever actually tries to set anything, it needs to be
5488  * to do the appropriate locking.
5489  */
5490 /* ARGSUSED */
5491 int
5492 udp_snmp_set(queue_t *q, t_scalar_t level, t_scalar_t name,
5493     uchar_t *ptr, int len)
5494 {
5495 	switch (level) {
5496 	case MIB2_UDP:
5497 		return (0);
5498 	default:
5499 		return (1);
5500 	}
5501 }
5502 
5503 static void
5504 udp_report_item(mblk_t *mp, udp_t *udp)
5505 {
5506 	char *state;
5507 	char addrbuf1[INET6_ADDRSTRLEN];
5508 	char addrbuf2[INET6_ADDRSTRLEN];
5509 	uint_t print_len, buf_len;
5510 
5511 	buf_len = mp->b_datap->db_lim - mp->b_wptr;
5512 	ASSERT(buf_len >= 0);
5513 	if (buf_len == 0)
5514 		return;
5515 
5516 	if (udp->udp_state == TS_UNBND)
5517 		state = "UNBOUND";
5518 	else if (udp->udp_state == TS_IDLE)
5519 		state = "IDLE";
5520 	else if (udp->udp_state == TS_DATA_XFER)
5521 		state = "CONNECTED";
5522 	else
5523 		state = "UnkState";
5524 	print_len = snprintf((char *)mp->b_wptr, buf_len,
5525 	    MI_COL_PTRFMT_STR "%4d %5u %s %s %5u %s\n",
5526 	    (void *)udp, udp->udp_connp->conn_zoneid, ntohs(udp->udp_port),
5527 	    inet_ntop(AF_INET6, &udp->udp_v6src,
5528 		addrbuf1, sizeof (addrbuf1)),
5529 	    inet_ntop(AF_INET6, &udp->udp_v6dst,
5530 		addrbuf2, sizeof (addrbuf2)),
5531 	    ntohs(udp->udp_dstport), state);
5532 	if (print_len < buf_len) {
5533 		mp->b_wptr += print_len;
5534 	} else {
5535 		mp->b_wptr += buf_len;
5536 	}
5537 }
5538 
5539 /* Report for ndd "udp_status" */
5540 /* ARGSUSED */
5541 static int
5542 udp_status_report(queue_t *q, mblk_t *mp, caddr_t cp, cred_t *cr)
5543 {
5544 	zoneid_t zoneid;
5545 	connf_t	*connfp;
5546 	conn_t	*connp = Q_TO_CONN(q);
5547 	udp_t	*udp = connp->conn_udp;
5548 	int	i;
5549 
5550 	/*
5551 	 * Because of the ndd constraint, at most we can have 64K buffer
5552 	 * to put in all UDP info.  So to be more efficient, just
5553 	 * allocate a 64K buffer here, assuming we need that large buffer.
5554 	 * This may be a problem as any user can read udp_status.  Therefore
5555 	 * we limit the rate of doing this using udp_ndd_get_info_interval.
5556 	 * This should be OK as normal users should not do this too often.
5557 	 */
5558 	if (cr == NULL || secpolicy_net_config(cr, B_TRUE) != 0) {
5559 		if (ddi_get_lbolt() - udp_last_ndd_get_info_time <
5560 		    drv_usectohz(udp_ndd_get_info_interval * 1000)) {
5561 			(void) mi_mpprintf(mp, NDD_TOO_QUICK_MSG);
5562 			return (0);
5563 		}
5564 	}
5565 	if ((mp->b_cont = allocb(ND_MAX_BUF_LEN, BPRI_HI)) == NULL) {
5566 		/* The following may work even if we cannot get a large buf. */
5567 		(void) mi_mpprintf(mp, NDD_OUT_OF_BUF_MSG);
5568 		return (0);
5569 	}
5570 	(void) mi_mpprintf(mp,
5571 	    "UDP     " MI_COL_HDRPAD_STR
5572 	/*   12345678[89ABCDEF] */
5573 	    " zone lport src addr        dest addr       port  state");
5574 	/*    1234 12345 xxx.xxx.xxx.xxx xxx.xxx.xxx.xxx 12345 UNBOUND */
5575 
5576 	zoneid = connp->conn_zoneid;
5577 
5578 	for (i = 0; i < CONN_G_HASH_SIZE; i++) {
5579 		connfp = &ipcl_globalhash_fanout[i];
5580 		connp = NULL;
5581 
5582 		while ((connp = ipcl_get_next_conn(connfp, connp,
5583 		    IPCL_UDP))) {
5584 			udp = connp->conn_udp;
5585 			if (zoneid != GLOBAL_ZONEID &&
5586 			    zoneid != connp->conn_zoneid)
5587 				continue;
5588 
5589 			udp_report_item(mp->b_cont, udp);
5590 		}
5591 	}
5592 	udp_last_ndd_get_info_time = ddi_get_lbolt();
5593 	return (0);
5594 }
5595 
5596 /*
5597  * This routine creates a T_UDERROR_IND message and passes it upstream.
5598  * The address and options are copied from the T_UNITDATA_REQ message
5599  * passed in mp.  This message is freed.
5600  */
5601 static void
5602 udp_ud_err(queue_t *q, mblk_t *mp, uchar_t *destaddr, t_scalar_t destlen,
5603     t_scalar_t err)
5604 {
5605 	struct T_unitdata_req *tudr;
5606 	mblk_t	*mp1;
5607 	uchar_t	*optaddr;
5608 	t_scalar_t optlen;
5609 
5610 	if (DB_TYPE(mp) == M_DATA) {
5611 		ASSERT(destaddr != NULL && destlen != 0);
5612 		optaddr = NULL;
5613 		optlen = 0;
5614 	} else {
5615 		if ((mp->b_wptr < mp->b_rptr) ||
5616 		    (MBLKL(mp)) < sizeof (struct T_unitdata_req)) {
5617 			goto done;
5618 		}
5619 		tudr = (struct T_unitdata_req *)mp->b_rptr;
5620 		destaddr = mp->b_rptr + tudr->DEST_offset;
5621 		if (destaddr < mp->b_rptr || destaddr >= mp->b_wptr ||
5622 		    destaddr + tudr->DEST_length < mp->b_rptr ||
5623 		    destaddr + tudr->DEST_length > mp->b_wptr) {
5624 			goto done;
5625 		}
5626 		optaddr = mp->b_rptr + tudr->OPT_offset;
5627 		if (optaddr < mp->b_rptr || optaddr >= mp->b_wptr ||
5628 		    optaddr + tudr->OPT_length < mp->b_rptr ||
5629 		    optaddr + tudr->OPT_length > mp->b_wptr) {
5630 			goto done;
5631 		}
5632 		destlen = tudr->DEST_length;
5633 		optlen = tudr->OPT_length;
5634 	}
5635 
5636 	mp1 = mi_tpi_uderror_ind((char *)destaddr, destlen,
5637 	    (char *)optaddr, optlen, err);
5638 	if (mp1 != NULL)
5639 		putnext(UDP_RD(q), mp1);
5640 
5641 done:
5642 	freemsg(mp);
5643 }
5644 
5645 /*
5646  * This routine removes a port number association from a stream.  It
5647  * is called by udp_wput to handle T_UNBIND_REQ messages.
5648  */
5649 static void
5650 udp_unbind(queue_t *q, mblk_t *mp)
5651 {
5652 	udp_t *udp = Q_TO_UDP(q);
5653 
5654 	/* If a bind has not been done, we can't unbind. */
5655 	if (udp->udp_state == TS_UNBND) {
5656 		udp_err_ack(q, mp, TOUTSTATE, 0);
5657 		return;
5658 	}
5659 	if (cl_inet_unbind != NULL) {
5660 		/*
5661 		 * Running in cluster mode - register unbind information
5662 		 */
5663 		if (udp->udp_ipversion == IPV4_VERSION) {
5664 			(*cl_inet_unbind)(IPPROTO_UDP, AF_INET,
5665 			    (uint8_t *)(&V4_PART_OF_V6(udp->udp_v6src)),
5666 			    (in_port_t)udp->udp_port);
5667 		} else {
5668 			(*cl_inet_unbind)(IPPROTO_UDP, AF_INET6,
5669 			    (uint8_t *)&(udp->udp_v6src),
5670 			    (in_port_t)udp->udp_port);
5671 		}
5672 	}
5673 
5674 	udp_bind_hash_remove(udp, B_FALSE);
5675 	V6_SET_ZERO(udp->udp_v6src);
5676 	V6_SET_ZERO(udp->udp_bound_v6src);
5677 	udp->udp_port = 0;
5678 	udp->udp_state = TS_UNBND;
5679 
5680 	if (udp->udp_family == AF_INET6) {
5681 		int error;
5682 
5683 		/* Rebuild the header template */
5684 		error = udp_build_hdrs(q, udp);
5685 		if (error != 0) {
5686 			udp_err_ack(q, mp, TSYSERR, error);
5687 			return;
5688 		}
5689 	}
5690 	/*
5691 	 * Pass the unbind to IP; T_UNBIND_REQ is larger than T_OK_ACK
5692 	 * and therefore ip_unbind must never return NULL.
5693 	 */
5694 	mp = ip_unbind(q, mp);
5695 	ASSERT(mp != NULL);
5696 	putnext(UDP_RD(q), mp);
5697 }
5698 
5699 /*
5700  * Don't let port fall into the privileged range.
5701  * Since the extra priviledged ports can be arbitrary we also
5702  * ensure that we exclude those from consideration.
5703  * udp_g_epriv_ports is not sorted thus we loop over it until
5704  * there are no changes.
5705  */
5706 static in_port_t
5707 udp_update_next_port(in_port_t port, boolean_t random)
5708 {
5709 	int i;
5710 
5711 	if (random && udp_random_anon_port != 0) {
5712 		(void) random_get_pseudo_bytes((uint8_t *)&port,
5713 		    sizeof (in_port_t));
5714 		/*
5715 		 * Unless changed by a sys admin, the smallest anon port
5716 		 * is 32768 and the largest anon port is 65535.  It is
5717 		 * very likely (50%) for the random port to be smaller
5718 		 * than the smallest anon port.  When that happens,
5719 		 * add port % (anon port range) to the smallest anon
5720 		 * port to get the random port.  It should fall into the
5721 		 * valid anon port range.
5722 		 */
5723 		if (port < udp_smallest_anon_port) {
5724 			port = udp_smallest_anon_port +
5725 			    port % (udp_largest_anon_port -
5726 			    udp_smallest_anon_port);
5727 		}
5728 	}
5729 
5730 retry:
5731 	if (port < udp_smallest_anon_port || port > udp_largest_anon_port)
5732 		port = udp_smallest_anon_port;
5733 
5734 	if (port < udp_smallest_nonpriv_port)
5735 		port = udp_smallest_nonpriv_port;
5736 
5737 	for (i = 0; i < udp_g_num_epriv_ports; i++) {
5738 		if (port == udp_g_epriv_ports[i]) {
5739 			port++;
5740 			/*
5741 			 * Make sure that the port is in the
5742 			 * valid range.
5743 			 */
5744 			goto retry;
5745 		}
5746 	}
5747 	return (port);
5748 }
5749 
5750 static mblk_t *
5751 udp_output_v4(conn_t *connp, mblk_t *mp, ipaddr_t v4dst, uint16_t port,
5752     uint_t srcid, int *error)
5753 {
5754 	udp_t	*udp = connp->conn_udp;
5755 	queue_t	*q = connp->conn_wq;
5756 	mblk_t	*mp1 = (DB_TYPE(mp) == M_DATA ? mp : mp->b_cont);
5757 	mblk_t	*mp2;
5758 	ipha_t	*ipha;
5759 	int	ip_hdr_length;
5760 	uint32_t ip_len;
5761 	udpha_t	*udpha;
5762 
5763 	*error = 0;
5764 
5765 	/* mp1 points to the M_DATA mblk carrying the packet */
5766 	ASSERT(mp1 != NULL && DB_TYPE(mp1) == M_DATA);
5767 
5768 	/* Add an IP header */
5769 	ip_hdr_length = IP_SIMPLE_HDR_LENGTH + UDPH_SIZE +
5770 	    udp->udp_ip_snd_options_len;
5771 	ipha = (ipha_t *)&mp1->b_rptr[-ip_hdr_length];
5772 	if (DB_REF(mp1) != 1 || (uchar_t *)ipha < DB_BASE(mp1) ||
5773 	    !OK_32PTR(ipha)) {
5774 		mp2 = allocb(ip_hdr_length + udp_wroff_extra, BPRI_LO);
5775 		if (mp2 == NULL) {
5776 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
5777 			    "udp_wput_end: q %p (%S)", q, "allocbfail2");
5778 			*error = ENOMEM;
5779 			goto done;
5780 		}
5781 		mp2->b_wptr = DB_LIM(mp2);
5782 		mp2->b_cont = mp1;
5783 		mp1 = mp2;
5784 		if (DB_TYPE(mp) != M_DATA)
5785 			mp->b_cont = mp1;
5786 		else
5787 			mp = mp1;
5788 
5789 		ipha = (ipha_t *)(mp1->b_wptr - ip_hdr_length);
5790 	}
5791 	ip_hdr_length -= UDPH_SIZE;
5792 #ifdef	_BIG_ENDIAN
5793 	/* Set version, header length, and tos */
5794 	*(uint16_t *)&ipha->ipha_version_and_hdr_length =
5795 	    ((((IP_VERSION << 4) | (ip_hdr_length>>2)) << 8) |
5796 		udp->udp_type_of_service);
5797 	/* Set ttl and protocol */
5798 	*(uint16_t *)&ipha->ipha_ttl = (udp->udp_ttl << 8) | IPPROTO_UDP;
5799 #else
5800 	/* Set version, header length, and tos */
5801 	*(uint16_t *)&ipha->ipha_version_and_hdr_length =
5802 		((udp->udp_type_of_service << 8) |
5803 		    ((IP_VERSION << 4) | (ip_hdr_length>>2)));
5804 	/* Set ttl and protocol */
5805 	*(uint16_t *)&ipha->ipha_ttl = (IPPROTO_UDP << 8) | udp->udp_ttl;
5806 #endif
5807 	/*
5808 	 * Copy our address into the packet.  If this is zero,
5809 	 * first look at __sin6_src_id for a hint. If we leave the source
5810 	 * as INADDR_ANY then ip will fill in the real source address.
5811 	 */
5812 	IN6_V4MAPPED_TO_IPADDR(&udp->udp_v6src, ipha->ipha_src);
5813 	if (srcid != 0 && ipha->ipha_src == INADDR_ANY) {
5814 		in6_addr_t v6src;
5815 
5816 		ip_srcid_find_id(srcid, &v6src, connp->conn_zoneid);
5817 		IN6_V4MAPPED_TO_IPADDR(&v6src, ipha->ipha_src);
5818 	}
5819 
5820 	ipha->ipha_fragment_offset_and_flags = 0;
5821 	ipha->ipha_ident = 0;
5822 
5823 	mp1->b_rptr = (uchar_t *)ipha;
5824 
5825 	ASSERT((uintptr_t)(mp1->b_wptr - (uchar_t *)ipha) <=
5826 	    (uintptr_t)UINT_MAX);
5827 
5828 	/* Determine length of packet */
5829 	ip_len = (uint32_t)(mp1->b_wptr - (uchar_t *)ipha);
5830 	if ((mp2 = mp1->b_cont) != NULL) {
5831 		do {
5832 			ASSERT((uintptr_t)MBLKL(mp2) <= (uintptr_t)UINT_MAX);
5833 			ip_len += (uint32_t)MBLKL(mp2);
5834 		} while ((mp2 = mp2->b_cont) != NULL);
5835 	}
5836 	/*
5837 	 * If the size of the packet is greater than the maximum allowed by
5838 	 * ip, return an error. Passing this down could cause panics because
5839 	 * the size will have wrapped and be inconsistent with the msg size.
5840 	 */
5841 	if (ip_len > IP_MAXPACKET) {
5842 		TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
5843 		    "udp_wput_end: q %p (%S)", q, "IP length exceeded");
5844 		*error = EMSGSIZE;
5845 		goto done;
5846 	}
5847 	ipha->ipha_length = htons((uint16_t)ip_len);
5848 	ip_len -= ip_hdr_length;
5849 	ip_len = htons((uint16_t)ip_len);
5850 	udpha = (udpha_t *)(((uchar_t *)ipha) + ip_hdr_length);
5851 
5852 	/*
5853 	 * Copy in the destination address
5854 	 */
5855 	if (v4dst == INADDR_ANY)
5856 		ipha->ipha_dst = htonl(INADDR_LOOPBACK);
5857 	else
5858 		ipha->ipha_dst = v4dst;
5859 
5860 	/*
5861 	 * Set ttl based on IP_MULTICAST_TTL to match IPv6 logic.
5862 	 */
5863 	if (CLASSD(v4dst))
5864 		ipha->ipha_ttl = udp->udp_multicast_ttl;
5865 
5866 	udpha->uha_dst_port = port;
5867 	udpha->uha_src_port = udp->udp_port;
5868 
5869 	if (ip_hdr_length > IP_SIMPLE_HDR_LENGTH) {
5870 		uint32_t	cksum;
5871 
5872 		bcopy(udp->udp_ip_snd_options, &ipha[1],
5873 		    udp->udp_ip_snd_options_len);
5874 		/*
5875 		 * Massage source route putting first source route in ipha_dst.
5876 		 * Ignore the destination in T_unitdata_req.
5877 		 * Create a checksum adjustment for a source route, if any.
5878 		 */
5879 		cksum = ip_massage_options(ipha);
5880 		cksum = (cksum & 0xFFFF) + (cksum >> 16);
5881 		cksum -= ((ipha->ipha_dst >> 16) & 0xFFFF) +
5882 		    (ipha->ipha_dst & 0xFFFF);
5883 		if ((int)cksum < 0)
5884 			cksum--;
5885 		cksum = (cksum & 0xFFFF) + (cksum >> 16);
5886 		/*
5887 		 * IP does the checksum if uha_checksum is non-zero,
5888 		 * We make it easy for IP to include our pseudo header
5889 		 * by putting our length in uha_checksum.
5890 		 */
5891 		cksum += ip_len;
5892 		cksum = (cksum & 0xFFFF) + (cksum >> 16);
5893 		/* There might be a carry. */
5894 		cksum = (cksum & 0xFFFF) + (cksum >> 16);
5895 #ifdef _LITTLE_ENDIAN
5896 		if (udp_do_checksum)
5897 			ip_len = (cksum << 16) | ip_len;
5898 #else
5899 		if (udp_do_checksum)
5900 			ip_len = (ip_len << 16) | cksum;
5901 		else
5902 			ip_len <<= 16;
5903 #endif
5904 	} else {
5905 		/*
5906 		 * IP does the checksum if uha_checksum is non-zero,
5907 		 * We make it easy for IP to include our pseudo header
5908 		 * by putting our length in uha_checksum.
5909 		 */
5910 		if (udp_do_checksum)
5911 			ip_len |= (ip_len << 16);
5912 #ifndef _LITTLE_ENDIAN
5913 		else
5914 			ip_len <<= 16;
5915 #endif
5916 	}
5917 	/* Set UDP length and checksum */
5918 	*((uint32_t *)&udpha->uha_length) = ip_len;
5919 
5920 	if (DB_TYPE(mp) != M_DATA) {
5921 		ASSERT(mp != mp1);
5922 		freeb(mp);
5923 	}
5924 
5925 	/* mp has been consumed and we'll return success */
5926 	ASSERT(*error == 0);
5927 	mp = NULL;
5928 
5929 	/* We're done.  Pass the packet to ip. */
5930 	BUMP_MIB(&udp_mib, udpOutDatagrams);
5931 	TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
5932 		"udp_wput_end: q %p (%S)", q, "end");
5933 
5934 	if ((connp->conn_flags & IPCL_CHECK_POLICY) != 0 ||
5935 	    CONN_OUTBOUND_POLICY_PRESENT(connp) ||
5936 	    connp->conn_dontroute || connp->conn_xmit_if_ill != NULL ||
5937 	    connp->conn_nofailover_ill != NULL ||
5938 	    connp->conn_outgoing_ill != NULL ||
5939 	    ipha->ipha_version_and_hdr_length != IP_SIMPLE_HDR_VERSION ||
5940 	    IPP_ENABLED(IPP_LOCAL_OUT) || ip_g_mrouter != NULL) {
5941 		UDP_STAT(udp_ip_send);
5942 		ip_output(connp, mp1, connp->conn_wq, IP_WPUT);
5943 	} else {
5944 		udp_send_data(udp, connp->conn_wq, mp1, ipha);
5945 	}
5946 
5947 done:
5948 	if (*error != 0) {
5949 		ASSERT(mp != NULL);
5950 		BUMP_MIB(&udp_mib, udpOutErrors);
5951 	}
5952 	return (mp);
5953 }
5954 
5955 static void
5956 udp_send_data(udp_t *udp, queue_t *q, mblk_t *mp, ipha_t *ipha)
5957 {
5958 	conn_t	*connp = udp->udp_connp;
5959 	ipaddr_t src, dst;
5960 	ill_t	*ill;
5961 	ire_t	*ire;
5962 	ipif_t	*ipif = NULL;
5963 	mblk_t	*ire_fp_mp;
5964 	uint_t	ire_fp_mp_len;
5965 	uint16_t *up;
5966 	uint32_t cksum, hcksum_txflags;
5967 	queue_t	*dev_q;
5968 	boolean_t retry_caching;
5969 
5970 	dst = ipha->ipha_dst;
5971 	src = ipha->ipha_src;
5972 	ASSERT(ipha->ipha_ident == 0);
5973 
5974 	if (CLASSD(dst)) {
5975 		int err;
5976 
5977 		ipif = conn_get_held_ipif(connp,
5978 		    &connp->conn_multicast_ipif, &err);
5979 
5980 		if (ipif == NULL || ipif->ipif_isv6 ||
5981 		    (ipif->ipif_ill->ill_phyint->phyint_flags &
5982 		    PHYI_LOOPBACK)) {
5983 			if (ipif != NULL)
5984 				ipif_refrele(ipif);
5985 			UDP_STAT(udp_ip_send);
5986 			ip_output(connp, mp, q, IP_WPUT);
5987 			return;
5988 		}
5989 	}
5990 
5991 	retry_caching = B_FALSE;
5992 	mutex_enter(&connp->conn_lock);
5993 	ire = connp->conn_ire_cache;
5994 	ASSERT(!(connp->conn_state_flags & CONN_INCIPIENT));
5995 
5996 	if (ire == NULL || ire->ire_addr != dst ||
5997 	    (ire->ire_marks & IRE_MARK_CONDEMNED)) {
5998 		retry_caching = B_TRUE;
5999 	} else if (CLASSD(dst) && (ire->ire_type & IRE_CACHE)) {
6000 		ill_t *stq_ill = (ill_t *)ire->ire_stq->q_ptr;
6001 
6002 		ASSERT(ipif != NULL);
6003 		if (stq_ill != ipif->ipif_ill && (stq_ill->ill_group == NULL ||
6004 		    stq_ill->ill_group != ipif->ipif_ill->ill_group))
6005 			retry_caching = B_TRUE;
6006 	}
6007 
6008 	if (!retry_caching) {
6009 		ASSERT(ire != NULL);
6010 		IRE_REFHOLD(ire);
6011 		mutex_exit(&connp->conn_lock);
6012 	} else {
6013 		boolean_t cached = B_FALSE;
6014 
6015 		connp->conn_ire_cache = NULL;
6016 		mutex_exit(&connp->conn_lock);
6017 
6018 		/* Release the old ire */
6019 		if (ire != NULL) {
6020 			IRE_REFRELE_NOTR(ire);
6021 			ire = NULL;
6022 		}
6023 
6024 		if (CLASSD(dst)) {
6025 			ASSERT(ipif != NULL);
6026 			ire = ire_ctable_lookup(dst, 0, 0, ipif,
6027 			    connp->conn_zoneid, MATCH_IRE_ILL_GROUP);
6028 		} else {
6029 			ASSERT(ipif == NULL);
6030 			ire = ire_cache_lookup(dst, connp->conn_zoneid);
6031 		}
6032 
6033 		if (ire == NULL) {
6034 			if (ipif != NULL)
6035 				ipif_refrele(ipif);
6036 			UDP_STAT(udp_ire_null);
6037 			ip_output(connp, mp, q, IP_WPUT);
6038 			return;
6039 		}
6040 		IRE_REFHOLD_NOTR(ire);
6041 
6042 		mutex_enter(&connp->conn_lock);
6043 		if (!(connp->conn_state_flags & CONN_CLOSING) &&
6044 		    connp->conn_ire_cache == NULL) {
6045 			rw_enter(&ire->ire_bucket->irb_lock, RW_READER);
6046 			if (!(ire->ire_marks & IRE_MARK_CONDEMNED)) {
6047 				connp->conn_ire_cache = ire;
6048 				cached = B_TRUE;
6049 			}
6050 			rw_exit(&ire->ire_bucket->irb_lock);
6051 		}
6052 		mutex_exit(&connp->conn_lock);
6053 
6054 		/*
6055 		 * We can continue to use the ire but since it was not
6056 		 * cached, we should drop the extra reference.
6057 		 */
6058 		if (!cached)
6059 			IRE_REFRELE_NOTR(ire);
6060 	}
6061 	ASSERT(ire != NULL && ire->ire_ipversion == IPV4_VERSION);
6062 	ASSERT(!CLASSD(dst) || ipif != NULL);
6063 
6064 	if ((ire->ire_type & (IRE_BROADCAST|IRE_LOCAL|IRE_LOOPBACK)) ||
6065 	    (ire->ire_flags & RTF_MULTIRT) || ire->ire_stq == NULL ||
6066 	    ire->ire_max_frag < ntohs(ipha->ipha_length) ||
6067 	    (ire_fp_mp = ire->ire_fp_mp) == NULL ||
6068 	    (connp->conn_nexthop_set) ||
6069 	    (ire_fp_mp_len = MBLKL(ire_fp_mp)) > MBLKHEAD(mp)) {
6070 		if (ipif != NULL)
6071 			ipif_refrele(ipif);
6072 		UDP_STAT(udp_ip_ire_send);
6073 		IRE_REFRELE(ire);
6074 		ip_output(connp, mp, q, IP_WPUT);
6075 		return;
6076 	}
6077 
6078 	BUMP_MIB(&ip_mib, ipOutRequests);
6079 
6080 	ill = ire_to_ill(ire);
6081 	ASSERT(ill != NULL);
6082 
6083 	dev_q = ire->ire_stq->q_next;
6084 	ASSERT(dev_q != NULL);
6085 	/*
6086 	 * If the service thread is already running, or if the driver
6087 	 * queue is currently flow-controlled, queue this packet.
6088 	 */
6089 	if ((q->q_first != NULL || connp->conn_draining) ||
6090 	    ((dev_q->q_next || dev_q->q_first) && !canput(dev_q))) {
6091 		if (ip_output_queue) {
6092 			(void) putq(q, mp);
6093 		} else {
6094 			BUMP_MIB(&ip_mib, ipOutDiscards);
6095 			freemsg(mp);
6096 		}
6097 		if (ipif != NULL)
6098 			ipif_refrele(ipif);
6099 		IRE_REFRELE(ire);
6100 		return;
6101 	}
6102 
6103 	ipha->ipha_ident = (uint16_t)atomic_add_32_nv(&ire->ire_ident, 1);
6104 #ifndef _BIG_ENDIAN
6105 	ipha->ipha_ident = (ipha->ipha_ident << 8) | (ipha->ipha_ident >> 8);
6106 #endif
6107 
6108 	if (src == INADDR_ANY && !connp->conn_unspec_src) {
6109 		if (CLASSD(dst) && !(ire->ire_flags & RTF_SETSRC))
6110 			src = ipha->ipha_src = ipif->ipif_src_addr;
6111 		else
6112 			src = ipha->ipha_src = ire->ire_src_addr;
6113 	}
6114 
6115 	if (ILL_HCKSUM_CAPABLE(ill) && dohwcksum) {
6116 		ASSERT(ill->ill_hcksum_capab != NULL);
6117 		hcksum_txflags = ill->ill_hcksum_capab->ill_hcksum_txflags;
6118 	} else {
6119 		hcksum_txflags = 0;
6120 	}
6121 
6122 	/* pseudo-header checksum (do it in parts for IP header checksum) */
6123 	cksum = (dst >> 16) + (dst & 0xFFFF) + (src >> 16) + (src & 0xFFFF);
6124 
6125 	ASSERT(ipha->ipha_version_and_hdr_length == IP_SIMPLE_HDR_VERSION);
6126 	up = IPH_UDPH_CHECKSUMP(ipha, IP_SIMPLE_HDR_LENGTH);
6127 	if (*up != 0) {
6128 		IP_CKSUM_XMIT_FAST(ire->ire_ipversion, hcksum_txflags,
6129 		    mp, ipha, up, IPPROTO_UDP, IP_SIMPLE_HDR_LENGTH,
6130 		    ntohs(ipha->ipha_length), cksum);
6131 
6132 		/* Software checksum? */
6133 		if (DB_CKSUMFLAGS(mp) == 0) {
6134 			UDP_STAT(udp_out_sw_cksum);
6135 			UDP_STAT_UPDATE(udp_out_sw_cksum_bytes,
6136 			    ntohs(ipha->ipha_length) - IP_SIMPLE_HDR_LENGTH);
6137 		}
6138 	}
6139 
6140 	ipha->ipha_fragment_offset_and_flags |=
6141 	    (uint32_t)htons(ire->ire_frag_flag);
6142 
6143 	/* Calculate IP header checksum if hardware isn't capable */
6144 	if (!(DB_CKSUMFLAGS(mp) & HCK_IPV4_HDRCKSUM)) {
6145 		IP_HDR_CKSUM(ipha, cksum, ((uint32_t *)ipha)[0],
6146 		    ((uint16_t *)ipha)[4]);
6147 	}
6148 
6149 	if (CLASSD(dst)) {
6150 		ilm_t *ilm;
6151 
6152 		ILM_WALKER_HOLD(ill);
6153 		ilm = ilm_lookup_ill(ill, dst, ALL_ZONES);
6154 		ILM_WALKER_RELE(ill);
6155 		if (ilm != NULL) {
6156 			ip_multicast_loopback(q, ill, mp,
6157 			    connp->conn_multicast_loop ? 0 :
6158 			    IP_FF_NO_MCAST_LOOP, connp->conn_zoneid);
6159 		}
6160 
6161 		/* If multicast TTL is 0 then we are done */
6162 		if (ipha->ipha_ttl == 0) {
6163 			if (ipif != NULL)
6164 				ipif_refrele(ipif);
6165 			freemsg(mp);
6166 			IRE_REFRELE(ire);
6167 			return;
6168 		}
6169 	}
6170 
6171 	ASSERT(DB_TYPE(ire_fp_mp) == M_DATA);
6172 	mp->b_rptr = (uchar_t *)ipha - ire_fp_mp_len;
6173 	bcopy(ire_fp_mp->b_rptr, mp->b_rptr, ire_fp_mp_len);
6174 
6175 	UPDATE_OB_PKT_COUNT(ire);
6176 	ire->ire_last_used_time = lbolt;
6177 
6178 	if (ILL_DLS_CAPABLE(ill)) {
6179 		/*
6180 		 * Send the packet directly to DLD, where it may be queued
6181 		 * depending on the availability of transmit resources at
6182 		 * the media layer.
6183 		 */
6184 		IP_DLS_ILL_TX(ill, mp);
6185 	} else {
6186 		putnext(ire->ire_stq, mp);
6187 	}
6188 
6189 	if (ipif != NULL)
6190 		ipif_refrele(ipif);
6191 	IRE_REFRELE(ire);
6192 }
6193 
6194 /*
6195  * This routine handles all messages passed downstream.  It either
6196  * consumes the message or passes it downstream; it never queues a
6197  * a message.
6198  */
6199 static void
6200 udp_output(conn_t *connp, mblk_t *mp, struct sockaddr *addr, socklen_t addrlen)
6201 {
6202 	sin6_t		*sin6;
6203 	sin_t		*sin;
6204 	ipaddr_t	v4dst;
6205 	uint16_t	port;
6206 	uint_t		srcid;
6207 	queue_t		*q = connp->conn_wq;
6208 	udp_t		*udp = connp->conn_udp;
6209 	t_scalar_t	optlen;
6210 	int		error = 0;
6211 	struct sockaddr_storage ss;
6212 
6213 	TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_START,
6214 	    "udp_wput_start: connp %p mp %p", connp, mp);
6215 
6216 	/*
6217 	 * We directly handle several cases here: T_UNITDATA_REQ message
6218 	 * coming down as M_PROTO/M_PCPROTO and M_DATA messages for both
6219 	 * connected and non-connected socket.  The latter carries the
6220 	 * address structure along when this routine gets called.
6221 	 */
6222 	switch (DB_TYPE(mp)) {
6223 	case M_DATA:
6224 		if (!udp->udp_direct_sockfs || udp->udp_state != TS_DATA_XFER) {
6225 			if (!udp->udp_direct_sockfs ||
6226 			    addr == NULL || addrlen == 0) {
6227 				/* Not connected; address is required */
6228 				BUMP_MIB(&udp_mib, udpOutErrors);
6229 				UDP_STAT(udp_out_err_notconn);
6230 				freemsg(mp);
6231 				TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6232 				    "udp_wput_end: connp %p (%S)", connp,
6233 				    "not-connected; address required");
6234 				return;
6235 			}
6236 			ASSERT(udp->udp_issocket);
6237 			UDP_DBGSTAT(udp_data_notconn);
6238 			/* Not connected; do some more checks below */
6239 			optlen = 0;
6240 			break;
6241 		}
6242 		/* M_DATA for connected socket */
6243 		UDP_DBGSTAT(udp_data_conn);
6244 		IN6_V4MAPPED_TO_IPADDR(&udp->udp_v6dst, v4dst);
6245 
6246 		/* Initialize addr and addrlen as if they're passed in */
6247 		if (udp->udp_family == AF_INET) {
6248 			sin = (sin_t *)&ss;
6249 			sin->sin_family = AF_INET;
6250 			sin->sin_port = udp->udp_dstport;
6251 			sin->sin_addr.s_addr = v4dst;
6252 			addr = (struct sockaddr *)sin;
6253 			addrlen = sizeof (*sin);
6254 		} else {
6255 			sin6 = (sin6_t *)&ss;
6256 			sin6->sin6_family = AF_INET6;
6257 			sin6->sin6_port = udp->udp_dstport;
6258 			sin6->sin6_flowinfo = udp->udp_flowinfo;
6259 			sin6->sin6_addr = udp->udp_v6dst;
6260 			sin6->sin6_scope_id = 0;
6261 			sin6->__sin6_src_id = 0;
6262 			addr = (struct sockaddr *)sin6;
6263 			addrlen = sizeof (*sin6);
6264 		}
6265 
6266 		if (udp->udp_family == AF_INET ||
6267 		    IN6_IS_ADDR_V4MAPPED(&udp->udp_v6dst)) {
6268 			/*
6269 			 * Handle both AF_INET and AF_INET6; the latter
6270 			 * for IPV4 mapped destination addresses.  Note
6271 			 * here that both addr and addrlen point to the
6272 			 * corresponding struct depending on the address
6273 			 * family of the socket.
6274 			 */
6275 			mp = udp_output_v4(connp, mp, v4dst,
6276 			    udp->udp_dstport, 0, &error);
6277 		} else {
6278 			mp = udp_output_v6(connp, mp, sin6, 0, &error);
6279 		}
6280 		if (error != 0) {
6281 			ASSERT(addr != NULL && addrlen != 0);
6282 			goto ud_error;
6283 		}
6284 		return;
6285 	case M_PROTO:
6286 	case M_PCPROTO: {
6287 		struct T_unitdata_req *tudr;
6288 
6289 		ASSERT((uintptr_t)MBLKL(mp) <= (uintptr_t)INT_MAX);
6290 		tudr = (struct T_unitdata_req *)mp->b_rptr;
6291 
6292 		/* Handle valid T_UNITDATA_REQ here */
6293 		if (MBLKL(mp) >= sizeof (*tudr) &&
6294 		    ((t_primp_t)mp->b_rptr)->type == T_UNITDATA_REQ) {
6295 			if (mp->b_cont == NULL) {
6296 				TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6297 				    "udp_wput_end: q %p (%S)", q, "badaddr");
6298 				error = EPROTO;
6299 				goto ud_error;
6300 			}
6301 
6302 			if (!MBLKIN(mp, 0, tudr->DEST_offset +
6303 			    tudr->DEST_length)) {
6304 				TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6305 				    "udp_wput_end: q %p (%S)", q, "badaddr");
6306 				error = EADDRNOTAVAIL;
6307 				goto ud_error;
6308 			}
6309 			/*
6310 			 * If a port has not been bound to the stream, fail.
6311 			 * This is not a problem when sockfs is directly
6312 			 * above us, because it will ensure that the socket
6313 			 * is first bound before allowing data to be sent.
6314 			 */
6315 			if (udp->udp_state == TS_UNBND) {
6316 				TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6317 				    "udp_wput_end: q %p (%S)", q, "outstate");
6318 				error = EPROTO;
6319 				goto ud_error;
6320 			}
6321 			addr = (struct sockaddr *)
6322 			    &mp->b_rptr[tudr->DEST_offset];
6323 			addrlen = tudr->DEST_length;
6324 			optlen = tudr->OPT_length;
6325 			if (optlen != 0)
6326 				UDP_STAT(udp_out_opt);
6327 			break;
6328 		}
6329 		/* FALLTHRU */
6330 	}
6331 	default:
6332 		udp_become_writer(connp, mp, udp_wput_other_wrapper,
6333 		    SQTAG_UDP_OUTPUT);
6334 		return;
6335 	}
6336 	ASSERT(addr != NULL);
6337 
6338 	switch (udp->udp_family) {
6339 	case AF_INET6:
6340 		sin6 = (sin6_t *)addr;
6341 		if (!OK_32PTR((char *)sin6) || addrlen != sizeof (sin6_t) ||
6342 		    sin6->sin6_family != AF_INET6) {
6343 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6344 			    "udp_wput_end: q %p (%S)", q, "badaddr");
6345 			error = EADDRNOTAVAIL;
6346 			goto ud_error;
6347 		}
6348 
6349 		if (!IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr)) {
6350 			/*
6351 			 * Destination is a non-IPv4-compatible IPv6 address.
6352 			 * Send out an IPv6 format packet.
6353 			 */
6354 			mp = udp_output_v6(connp, mp, sin6, optlen, &error);
6355 			if (error != 0)
6356 				goto ud_error;
6357 
6358 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6359 			    "udp_wput_end: q %p (%S)", q, "udp_output_v6");
6360 			return;
6361 		}
6362 		/*
6363 		 * If the local address is not zero or a mapped address
6364 		 * return an error.  It would be possible to send an IPv4
6365 		 * packet but the response would never make it back to the
6366 		 * application since it is bound to a non-mapped address.
6367 		 */
6368 		if (!IN6_IS_ADDR_V4MAPPED(&udp->udp_v6src) &&
6369 		    !IN6_IS_ADDR_UNSPECIFIED(&udp->udp_v6src)) {
6370 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6371 			    "udp_wput_end: q %p (%S)", q, "badaddr");
6372 			error = EADDRNOTAVAIL;
6373 			goto ud_error;
6374 		}
6375 		/* Send IPv4 packet without modifying udp_ipversion */
6376 		/* Extract port and ipaddr */
6377 		port = sin6->sin6_port;
6378 		IN6_V4MAPPED_TO_IPADDR(&sin6->sin6_addr, v4dst);
6379 		srcid = sin6->__sin6_src_id;
6380 		break;
6381 
6382 	case AF_INET:
6383 		sin = (sin_t *)addr;
6384 		if (!OK_32PTR((char *)sin) || addrlen != sizeof (sin_t) ||
6385 		    sin->sin_family != AF_INET) {
6386 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6387 			    "udp_wput_end: q %p (%S)", q, "badaddr");
6388 			error = EADDRNOTAVAIL;
6389 			goto ud_error;
6390 		}
6391 		/* Extract port and ipaddr */
6392 		port = sin->sin_port;
6393 		v4dst = sin->sin_addr.s_addr;
6394 		srcid = 0;
6395 		break;
6396 	}
6397 
6398 	/*
6399 	 * If options passed in, feed it for verification and handling
6400 	 */
6401 	if (optlen != 0) {
6402 		ASSERT(DB_TYPE(mp) != M_DATA);
6403 		if (udp_unitdata_opt_process(q, mp, &error, NULL) < 0) {
6404 			/* failure */
6405 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_END,
6406 			    "udp_wput_end: q %p (%S)", q,
6407 			    "udp_unitdata_opt_process");
6408 			goto ud_error;
6409 		}
6410 		/*
6411 		 * Note: success in processing options.
6412 		 * mp option buffer represented by
6413 		 * OPT_length/offset now potentially modified
6414 		 * and contain option setting results
6415 		 */
6416 	}
6417 	ASSERT(error == 0);
6418 	mp = udp_output_v4(connp, mp, v4dst, port, srcid, &error);
6419 	if (error != 0) {
6420 ud_error:
6421 		UDP_STAT(udp_out_err_output);
6422 		ASSERT(mp != NULL);
6423 		/* mp is freed by the following routine */
6424 		udp_ud_err(q, mp, (uchar_t *)addr, (t_scalar_t)addrlen,
6425 		    (t_scalar_t)error);
6426 	}
6427 }
6428 
6429 /* ARGSUSED */
6430 static void
6431 udp_output_wrapper(void *arg, mblk_t *mp, void *arg2)
6432 {
6433 	udp_output((conn_t *)arg, mp, NULL, 0);
6434 	_UDP_EXIT((conn_t *)arg);
6435 }
6436 
6437 static void
6438 udp_wput(queue_t *q, mblk_t *mp)
6439 {
6440 	_UDP_ENTER(Q_TO_CONN(UDP_WR(q)), mp, udp_output_wrapper,
6441 	    SQTAG_UDP_WPUT);
6442 }
6443 
6444 /*
6445  * Allocate and prepare a T_UNITDATA_REQ message.
6446  */
6447 static mblk_t *
6448 udp_tudr_alloc(struct sockaddr *addr, socklen_t addrlen)
6449 {
6450 	struct T_unitdata_req *tudr;
6451 	mblk_t *mp;
6452 
6453 	mp = allocb(sizeof (*tudr) + addrlen, BPRI_MED);
6454 	if (mp != NULL) {
6455 		mp->b_wptr += sizeof (*tudr) + addrlen;
6456 		DB_TYPE(mp) = M_PROTO;
6457 
6458 		tudr = (struct T_unitdata_req *)mp->b_rptr;
6459 		tudr->PRIM_type = T_UNITDATA_REQ;
6460 		tudr->DEST_length = addrlen;
6461 		tudr->DEST_offset = (t_scalar_t)sizeof (*tudr);
6462 		tudr->OPT_length = 0;
6463 		tudr->OPT_offset = 0;
6464 		bcopy(addr, tudr+1, addrlen);
6465 	}
6466 	return (mp);
6467 }
6468 
6469 /*
6470  * Entry point for sockfs when udp is in "direct sockfs" mode.  This mode
6471  * is valid when we are directly beneath the stream head, and thus sockfs
6472  * is able to bypass STREAMS and directly call us, passing along the sockaddr
6473  * structure without the cumbersome T_UNITDATA_REQ interface.  Note that
6474  * this is done for both connected and non-connected endpoint.
6475  */
6476 void
6477 udp_wput_data(queue_t *q, mblk_t *mp, struct sockaddr *addr, socklen_t addrlen)
6478 {
6479 	conn_t	*connp;
6480 	udp_t	*udp;
6481 
6482 	q = UDP_WR(q);
6483 	connp = Q_TO_CONN(q);
6484 	udp = connp->conn_udp;
6485 
6486 	/* udpsockfs should only send down M_DATA for this entry point */
6487 	ASSERT(DB_TYPE(mp) == M_DATA);
6488 
6489 	mutex_enter(&connp->conn_lock);
6490 	UDP_MODE_ASSERTIONS(udp, UDP_ENTER);
6491 
6492 	if (udp->udp_mode != UDP_MT_HOT) {
6493 		/*
6494 		 * We can't enter this conn right away because another
6495 		 * thread is currently executing as writer; therefore we
6496 		 * need to deposit the message into the squeue to be
6497 		 * drained later.  If a socket address is present, we
6498 		 * need to create a T_UNITDATA_REQ message as placeholder.
6499 		 */
6500 		if (addr != NULL && addrlen != 0) {
6501 			mblk_t *tudr_mp = udp_tudr_alloc(addr, addrlen);
6502 
6503 			if (tudr_mp == NULL) {
6504 				mutex_exit(&connp->conn_lock);
6505 				BUMP_MIB(&udp_mib, udpOutErrors);
6506 				UDP_STAT(udp_out_err_tudr);
6507 				freemsg(mp);
6508 				return;
6509 			}
6510 			/* Tag the packet with T_UNITDATA_REQ */
6511 			tudr_mp->b_cont = mp;
6512 			mp = tudr_mp;
6513 		}
6514 		mutex_exit(&connp->conn_lock);
6515 		udp_enter(connp, mp, udp_output_wrapper, SQTAG_UDP_WPUT);
6516 		return;
6517 	}
6518 
6519 	/* We can execute as reader right away. */
6520 	UDP_READERS_INCREF(udp);
6521 	mutex_exit(&connp->conn_lock);
6522 
6523 	udp_output(connp, mp, addr, addrlen);
6524 
6525 	mutex_enter(&connp->conn_lock);
6526 	UDP_MODE_ASSERTIONS(udp, UDP_EXIT);
6527 	UDP_READERS_DECREF(udp);
6528 	mutex_exit(&connp->conn_lock);
6529 }
6530 
6531 /*
6532  * udp_output_v6():
6533  * Assumes that udp_wput did some sanity checking on the destination
6534  * address.
6535  */
6536 static mblk_t *
6537 udp_output_v6(conn_t *connp, mblk_t *mp, sin6_t *sin6, t_scalar_t tudr_optlen,
6538     int *error)
6539 {
6540 	ip6_t		*ip6h;
6541 	ip6i_t		*ip6i;	/* mp1->b_rptr even if no ip6i_t */
6542 	mblk_t		*mp1 = (DB_TYPE(mp) == M_DATA ? mp : mp->b_cont);
6543 	mblk_t		*mp2;
6544 	int		udp_ip_hdr_len = IPV6_HDR_LEN + UDPH_SIZE;
6545 	size_t		ip_len;
6546 	udpha_t		*udph;
6547 	udp_t		*udp = connp->conn_udp;
6548 	queue_t		*q = connp->conn_wq;
6549 	ip6_pkt_t	ipp_s;	/* For ancillary data options */
6550 	ip6_pkt_t	*ipp = &ipp_s;
6551 	ip6_pkt_t	*tipp;	/* temporary ipp */
6552 	uint32_t	csum = 0;
6553 	uint_t		ignore = 0;
6554 	uint_t		option_exists = 0, is_sticky = 0;
6555 	uint8_t		*cp;
6556 	uint8_t		*nxthdr_ptr;
6557 
6558 	*error = 0;
6559 
6560 	/* mp1 points to the M_DATA mblk carrying the packet */
6561 	ASSERT(mp1 != NULL && DB_TYPE(mp1) == M_DATA);
6562 	ASSERT(tudr_optlen == 0 || DB_TYPE(mp) != M_DATA);
6563 
6564 	/*
6565 	 * If the local address is a mapped address return
6566 	 * an error.
6567 	 * It would be possible to send an IPv6 packet but the
6568 	 * response would never make it back to the application
6569 	 * since it is bound to a mapped address.
6570 	 */
6571 	if (IN6_IS_ADDR_V4MAPPED(&udp->udp_v6src)) {
6572 		*error = EADDRNOTAVAIL;
6573 		goto done;
6574 	}
6575 
6576 	ipp->ipp_fields = 0;
6577 	ipp->ipp_sticky_ignored = 0;
6578 
6579 	/*
6580 	 * If TPI options passed in, feed it for verification and handling
6581 	 */
6582 	if (tudr_optlen != 0) {
6583 		if (udp_unitdata_opt_process(q, mp, error, (void *)ipp) < 0) {
6584 			/* failure */
6585 			goto done;
6586 		}
6587 		ignore = ipp->ipp_sticky_ignored;
6588 		ASSERT(*error == 0);
6589 	}
6590 
6591 	if (sin6->sin6_scope_id != 0 &&
6592 	    IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
6593 		/*
6594 		 * IPPF_SCOPE_ID is special.  It's neither a sticky
6595 		 * option nor ancillary data.  It needs to be
6596 		 * explicitly set in options_exists.
6597 		 */
6598 		option_exists |= IPPF_SCOPE_ID;
6599 	}
6600 
6601 	if ((udp->udp_sticky_ipp.ipp_fields == 0) && (ipp->ipp_fields == 0)) {
6602 		/* No sticky options nor ancillary data. */
6603 		goto no_options;
6604 	}
6605 
6606 	/*
6607 	 * Go through the options figuring out where each is going to
6608 	 * come from and build two masks.  The first mask indicates if
6609 	 * the option exists at all.  The second mask indicates if the
6610 	 * option is sticky or ancillary.
6611 	 */
6612 	if (!(ignore & IPPF_HOPOPTS)) {
6613 		if (ipp->ipp_fields & IPPF_HOPOPTS) {
6614 			option_exists |= IPPF_HOPOPTS;
6615 			udp_ip_hdr_len += ipp->ipp_hopoptslen;
6616 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_HOPOPTS) {
6617 			option_exists |= IPPF_HOPOPTS;
6618 			is_sticky |= IPPF_HOPOPTS;
6619 			udp_ip_hdr_len += udp->udp_sticky_ipp.ipp_hopoptslen;
6620 		}
6621 	}
6622 
6623 	if (!(ignore & IPPF_RTHDR)) {
6624 		if (ipp->ipp_fields & IPPF_RTHDR) {
6625 			option_exists |= IPPF_RTHDR;
6626 			udp_ip_hdr_len += ipp->ipp_rthdrlen;
6627 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_RTHDR) {
6628 			option_exists |= IPPF_RTHDR;
6629 			is_sticky |= IPPF_RTHDR;
6630 			udp_ip_hdr_len += udp->udp_sticky_ipp.ipp_rthdrlen;
6631 		}
6632 	}
6633 
6634 	if (!(ignore & IPPF_RTDSTOPTS) && (option_exists & IPPF_RTHDR)) {
6635 		if (ipp->ipp_fields & IPPF_RTDSTOPTS) {
6636 			option_exists |= IPPF_RTDSTOPTS;
6637 			udp_ip_hdr_len += ipp->ipp_rtdstoptslen;
6638 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_RTDSTOPTS) {
6639 			option_exists |= IPPF_RTDSTOPTS;
6640 			is_sticky |= IPPF_RTDSTOPTS;
6641 			udp_ip_hdr_len += udp->udp_sticky_ipp.ipp_rtdstoptslen;
6642 		}
6643 	}
6644 
6645 	if (!(ignore & IPPF_DSTOPTS)) {
6646 		if (ipp->ipp_fields & IPPF_DSTOPTS) {
6647 			option_exists |= IPPF_DSTOPTS;
6648 			udp_ip_hdr_len += ipp->ipp_dstoptslen;
6649 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_DSTOPTS) {
6650 			option_exists |= IPPF_DSTOPTS;
6651 			is_sticky |= IPPF_DSTOPTS;
6652 			udp_ip_hdr_len += udp->udp_sticky_ipp.ipp_dstoptslen;
6653 		}
6654 	}
6655 
6656 	if (!(ignore & IPPF_IFINDEX)) {
6657 		if (ipp->ipp_fields & IPPF_IFINDEX) {
6658 			option_exists |= IPPF_IFINDEX;
6659 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_IFINDEX) {
6660 			option_exists |= IPPF_IFINDEX;
6661 			is_sticky |= IPPF_IFINDEX;
6662 		}
6663 	}
6664 
6665 	if (!(ignore & IPPF_ADDR)) {
6666 		if (ipp->ipp_fields & IPPF_ADDR) {
6667 			option_exists |= IPPF_ADDR;
6668 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_ADDR) {
6669 			option_exists |= IPPF_ADDR;
6670 			is_sticky |= IPPF_ADDR;
6671 		}
6672 	}
6673 
6674 	if (!(ignore & IPPF_DONTFRAG)) {
6675 		if (ipp->ipp_fields & IPPF_DONTFRAG) {
6676 			option_exists |= IPPF_DONTFRAG;
6677 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_DONTFRAG) {
6678 			option_exists |= IPPF_DONTFRAG;
6679 			is_sticky |= IPPF_DONTFRAG;
6680 		}
6681 	}
6682 
6683 	if (!(ignore & IPPF_USE_MIN_MTU)) {
6684 		if (ipp->ipp_fields & IPPF_USE_MIN_MTU) {
6685 			option_exists |= IPPF_USE_MIN_MTU;
6686 		} else if (udp->udp_sticky_ipp.ipp_fields &
6687 		    IPPF_USE_MIN_MTU) {
6688 			option_exists |= IPPF_USE_MIN_MTU;
6689 			is_sticky |= IPPF_USE_MIN_MTU;
6690 		}
6691 	}
6692 
6693 	if (!(ignore & IPPF_HOPLIMIT) && (ipp->ipp_fields & IPPF_HOPLIMIT))
6694 		option_exists |= IPPF_HOPLIMIT;
6695 	/* IPV6_HOPLIMIT can never be sticky */
6696 	ASSERT(!(udp->udp_sticky_ipp.ipp_fields & IPPF_HOPLIMIT));
6697 
6698 	if (!(ignore & IPPF_UNICAST_HOPS) &&
6699 	    (udp->udp_sticky_ipp.ipp_fields & IPPF_UNICAST_HOPS)) {
6700 		option_exists |= IPPF_UNICAST_HOPS;
6701 		is_sticky |= IPPF_UNICAST_HOPS;
6702 	}
6703 
6704 	if (!(ignore & IPPF_MULTICAST_HOPS) &&
6705 	    (udp->udp_sticky_ipp.ipp_fields & IPPF_MULTICAST_HOPS)) {
6706 		option_exists |= IPPF_MULTICAST_HOPS;
6707 		is_sticky |= IPPF_MULTICAST_HOPS;
6708 	}
6709 
6710 	if (!(ignore & IPPF_TCLASS)) {
6711 		if (ipp->ipp_fields & IPPF_TCLASS) {
6712 			option_exists |= IPPF_TCLASS;
6713 		} else if (udp->udp_sticky_ipp.ipp_fields & IPPF_TCLASS) {
6714 			option_exists |= IPPF_TCLASS;
6715 			is_sticky |= IPPF_TCLASS;
6716 		}
6717 	}
6718 
6719 no_options:
6720 
6721 	/*
6722 	 * If any options carried in the ip6i_t were specified, we
6723 	 * need to account for the ip6i_t in the data we'll be sending
6724 	 * down.
6725 	 */
6726 	if (option_exists & IPPF_HAS_IP6I)
6727 		udp_ip_hdr_len += sizeof (ip6i_t);
6728 
6729 	/* check/fix buffer config, setup pointers into it */
6730 	ip6h = (ip6_t *)&mp1->b_rptr[-udp_ip_hdr_len];
6731 	if (DB_REF(mp1) != 1 || ((unsigned char *)ip6h < DB_BASE(mp1)) ||
6732 	    !OK_32PTR(ip6h)) {
6733 		/* Try to get everything in a single mblk next time */
6734 		if (udp_ip_hdr_len > udp->udp_max_hdr_len) {
6735 			udp->udp_max_hdr_len = udp_ip_hdr_len;
6736 			(void) mi_set_sth_wroff(UDP_RD(q),
6737 			    udp->udp_max_hdr_len + udp_wroff_extra);
6738 		}
6739 		mp2 = allocb(udp_ip_hdr_len + udp_wroff_extra, BPRI_LO);
6740 		if (mp2 == NULL) {
6741 			*error = ENOMEM;
6742 			goto done;
6743 		}
6744 		mp2->b_wptr = DB_LIM(mp2);
6745 		mp2->b_cont = mp1;
6746 		mp1 = mp2;
6747 		if (DB_TYPE(mp) != M_DATA)
6748 			mp->b_cont = mp1;
6749 		else
6750 			mp = mp1;
6751 
6752 		ip6h = (ip6_t *)(mp1->b_wptr - udp_ip_hdr_len);
6753 	}
6754 	mp1->b_rptr = (unsigned char *)ip6h;
6755 	ip6i = (ip6i_t *)ip6h;
6756 
6757 #define	ANCIL_OR_STICKY_PTR(f) ((is_sticky & f) ? &udp->udp_sticky_ipp : ipp)
6758 	if (option_exists & IPPF_HAS_IP6I) {
6759 		ip6h = (ip6_t *)&ip6i[1];
6760 		ip6i->ip6i_flags = 0;
6761 		ip6i->ip6i_vcf = IPV6_DEFAULT_VERS_AND_FLOW;
6762 
6763 		/* sin6_scope_id takes precendence over IPPF_IFINDEX */
6764 		if (option_exists & IPPF_SCOPE_ID) {
6765 			ip6i->ip6i_flags |= IP6I_IFINDEX;
6766 			ip6i->ip6i_ifindex = sin6->sin6_scope_id;
6767 		} else if (option_exists & IPPF_IFINDEX) {
6768 			tipp = ANCIL_OR_STICKY_PTR(IPPF_IFINDEX);
6769 			ASSERT(tipp->ipp_ifindex != 0);
6770 			ip6i->ip6i_flags |= IP6I_IFINDEX;
6771 			ip6i->ip6i_ifindex = tipp->ipp_ifindex;
6772 		}
6773 
6774 		if (option_exists & IPPF_ADDR) {
6775 			/*
6776 			 * Enable per-packet source address verification if
6777 			 * IPV6_PKTINFO specified the source address.
6778 			 * ip6_src is set in the transport's _wput function.
6779 			 */
6780 			ip6i->ip6i_flags |= IP6I_VERIFY_SRC;
6781 		}
6782 
6783 		if (option_exists & IPPF_DONTFRAG) {
6784 			ip6i->ip6i_flags |= IP6I_DONTFRAG;
6785 		}
6786 
6787 		if (option_exists & IPPF_USE_MIN_MTU) {
6788 			ip6i->ip6i_flags = IP6I_API_USE_MIN_MTU(
6789 			    ip6i->ip6i_flags, ipp->ipp_use_min_mtu);
6790 		}
6791 
6792 		if (option_exists & IPPF_NEXTHOP) {
6793 			tipp = ANCIL_OR_STICKY_PTR(IPPF_NEXTHOP);
6794 			ASSERT(!IN6_IS_ADDR_UNSPECIFIED(&tipp->ipp_nexthop));
6795 			ip6i->ip6i_flags |= IP6I_NEXTHOP;
6796 			ip6i->ip6i_nexthop = tipp->ipp_nexthop;
6797 		}
6798 
6799 		/*
6800 		 * tell IP this is an ip6i_t private header
6801 		 */
6802 		ip6i->ip6i_nxt = IPPROTO_RAW;
6803 	}
6804 
6805 	/* Initialize IPv6 header */
6806 	ip6h->ip6_vcf = IPV6_DEFAULT_VERS_AND_FLOW;
6807 	bzero(&ip6h->ip6_src, sizeof (ip6h->ip6_src));
6808 
6809 	/* Set the hoplimit of the outgoing packet. */
6810 	if (option_exists & IPPF_HOPLIMIT) {
6811 		/* IPV6_HOPLIMIT ancillary data overrides all other settings. */
6812 		ip6h->ip6_hops = ipp->ipp_hoplimit;
6813 		ip6i->ip6i_flags |= IP6I_HOPLIMIT;
6814 	} else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr)) {
6815 		ip6h->ip6_hops = udp->udp_multicast_ttl;
6816 		if (option_exists & IPPF_MULTICAST_HOPS)
6817 			ip6i->ip6i_flags |= IP6I_HOPLIMIT;
6818 	} else {
6819 		ip6h->ip6_hops = udp->udp_ttl;
6820 		if (option_exists & IPPF_UNICAST_HOPS)
6821 			ip6i->ip6i_flags |= IP6I_HOPLIMIT;
6822 	}
6823 
6824 	if (option_exists & IPPF_ADDR) {
6825 		tipp = ANCIL_OR_STICKY_PTR(IPPF_ADDR);
6826 		ASSERT(!IN6_IS_ADDR_UNSPECIFIED(&tipp->ipp_addr));
6827 		ip6h->ip6_src = tipp->ipp_addr;
6828 	} else {
6829 		/*
6830 		 * The source address was not set using IPV6_PKTINFO.
6831 		 * First look at the bound source.
6832 		 * If unspecified fallback to __sin6_src_id.
6833 		 */
6834 		ip6h->ip6_src = udp->udp_v6src;
6835 		if (sin6->__sin6_src_id != 0 &&
6836 		    IN6_IS_ADDR_UNSPECIFIED(&ip6h->ip6_src)) {
6837 			ip_srcid_find_id(sin6->__sin6_src_id,
6838 			    &ip6h->ip6_src, connp->conn_zoneid);
6839 		}
6840 	}
6841 
6842 	nxthdr_ptr = (uint8_t *)&ip6h->ip6_nxt;
6843 	cp = (uint8_t *)&ip6h[1];
6844 
6845 	/*
6846 	 * Here's where we have to start stringing together
6847 	 * any extension headers in the right order:
6848 	 * Hop-by-hop, destination, routing, and final destination opts.
6849 	 */
6850 	if (option_exists & IPPF_HOPOPTS) {
6851 		/* Hop-by-hop options */
6852 		ip6_hbh_t *hbh = (ip6_hbh_t *)cp;
6853 		tipp = ANCIL_OR_STICKY_PTR(IPPF_HOPOPTS);
6854 
6855 		*nxthdr_ptr = IPPROTO_HOPOPTS;
6856 		nxthdr_ptr = &hbh->ip6h_nxt;
6857 
6858 		bcopy(tipp->ipp_hopopts, cp, tipp->ipp_hopoptslen);
6859 		cp += tipp->ipp_hopoptslen;
6860 	}
6861 	/*
6862 	 * En-route destination options
6863 	 * Only do them if there's a routing header as well
6864 	 */
6865 	if (option_exists & IPPF_RTDSTOPTS) {
6866 		ip6_dest_t *dst = (ip6_dest_t *)cp;
6867 		tipp = ANCIL_OR_STICKY_PTR(IPPF_RTDSTOPTS);
6868 
6869 		*nxthdr_ptr = IPPROTO_DSTOPTS;
6870 		nxthdr_ptr = &dst->ip6d_nxt;
6871 
6872 		bcopy(tipp->ipp_rtdstopts, cp, tipp->ipp_rtdstoptslen);
6873 		cp += tipp->ipp_rtdstoptslen;
6874 	}
6875 	/*
6876 	 * Routing header next
6877 	 */
6878 	if (option_exists & IPPF_RTHDR) {
6879 		ip6_rthdr_t *rt = (ip6_rthdr_t *)cp;
6880 		tipp = ANCIL_OR_STICKY_PTR(IPPF_RTHDR);
6881 
6882 		*nxthdr_ptr = IPPROTO_ROUTING;
6883 		nxthdr_ptr = &rt->ip6r_nxt;
6884 
6885 		bcopy(tipp->ipp_rthdr, cp, tipp->ipp_rthdrlen);
6886 		cp += tipp->ipp_rthdrlen;
6887 	}
6888 	/*
6889 	 * Do ultimate destination options
6890 	 */
6891 	if (option_exists & IPPF_DSTOPTS) {
6892 		ip6_dest_t *dest = (ip6_dest_t *)cp;
6893 		tipp = ANCIL_OR_STICKY_PTR(IPPF_DSTOPTS);
6894 
6895 		*nxthdr_ptr = IPPROTO_DSTOPTS;
6896 		nxthdr_ptr = &dest->ip6d_nxt;
6897 
6898 		bcopy(tipp->ipp_dstopts, cp, tipp->ipp_dstoptslen);
6899 		cp += tipp->ipp_dstoptslen;
6900 	}
6901 	/*
6902 	 * Now set the last header pointer to the proto passed in
6903 	 */
6904 	ASSERT((int)(cp - (uint8_t *)ip6i) == (udp_ip_hdr_len - UDPH_SIZE));
6905 	*nxthdr_ptr = IPPROTO_UDP;
6906 
6907 	/* Update UDP header */
6908 	udph = (udpha_t *)((uchar_t *)ip6i + udp_ip_hdr_len - UDPH_SIZE);
6909 	udph->uha_dst_port = sin6->sin6_port;
6910 	udph->uha_src_port = udp->udp_port;
6911 
6912 	/*
6913 	 * Copy in the destination address
6914 	 */
6915 	if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
6916 		ip6h->ip6_dst = ipv6_loopback;
6917 	else
6918 		ip6h->ip6_dst = sin6->sin6_addr;
6919 
6920 	ip6h->ip6_vcf =
6921 	    (IPV6_DEFAULT_VERS_AND_FLOW & IPV6_VERS_AND_FLOW_MASK) |
6922 	    (sin6->sin6_flowinfo & ~IPV6_VERS_AND_FLOW_MASK);
6923 
6924 	if (option_exists & IPPF_TCLASS) {
6925 		tipp = ANCIL_OR_STICKY_PTR(IPPF_TCLASS);
6926 		ip6h->ip6_vcf = IPV6_TCLASS_FLOW(ip6h->ip6_vcf,
6927 		    tipp->ipp_tclass);
6928 	}
6929 
6930 	if (option_exists & IPPF_RTHDR) {
6931 		ip6_rthdr_t	*rth;
6932 
6933 		/*
6934 		 * Perform any processing needed for source routing.
6935 		 * We know that all extension headers will be in the same mblk
6936 		 * as the IPv6 header.
6937 		 */
6938 		rth = ip_find_rthdr_v6(ip6h, mp1->b_wptr);
6939 		if (rth != NULL && rth->ip6r_segleft != 0) {
6940 			if (rth->ip6r_type != IPV6_RTHDR_TYPE_0) {
6941 				/*
6942 				 * Drop packet - only support Type 0 routing.
6943 				 * Notify the application as well.
6944 				 */
6945 				*error = EPROTO;
6946 				goto done;
6947 			}
6948 
6949 			/*
6950 			 * rth->ip6r_len is twice the number of
6951 			 * addresses in the header. Thus it must be even.
6952 			 */
6953 			if (rth->ip6r_len & 0x1) {
6954 				*error = EPROTO;
6955 				goto done;
6956 			}
6957 			/*
6958 			 * Shuffle the routing header and ip6_dst
6959 			 * addresses, and get the checksum difference
6960 			 * between the first hop (in ip6_dst) and
6961 			 * the destination (in the last routing hdr entry).
6962 			 */
6963 			csum = ip_massage_options_v6(ip6h, rth);
6964 			/*
6965 			 * Verify that the first hop isn't a mapped address.
6966 			 * Routers along the path need to do this verification
6967 			 * for subsequent hops.
6968 			 */
6969 			if (IN6_IS_ADDR_V4MAPPED(&ip6h->ip6_dst)) {
6970 				*error = EADDRNOTAVAIL;
6971 				goto done;
6972 			}
6973 
6974 			cp += (rth->ip6r_len + 1)*8;
6975 		}
6976 	}
6977 
6978 	/* count up length of UDP packet */
6979 	ip_len = (mp1->b_wptr - (unsigned char *)ip6h) - IPV6_HDR_LEN;
6980 	if ((mp2 = mp1->b_cont) != NULL) {
6981 		do {
6982 			ASSERT((uintptr_t)MBLKL(mp2) <= (uintptr_t)UINT_MAX);
6983 			ip_len += (uint32_t)MBLKL(mp2);
6984 		} while ((mp2 = mp2->b_cont) != NULL);
6985 	}
6986 
6987 	/*
6988 	 * If the size of the packet is greater than the maximum allowed by
6989 	 * ip, return an error. Passing this down could cause panics because
6990 	 * the size will have wrapped and be inconsistent with the msg size.
6991 	 */
6992 	if (ip_len > IP_MAXPACKET) {
6993 		*error = EMSGSIZE;
6994 		goto done;
6995 	}
6996 
6997 	/* Store the UDP length. Subtract length of extension hdrs */
6998 	udph->uha_length = htons(ip_len + IPV6_HDR_LEN -
6999 	    (int)((uchar_t *)udph - (uchar_t *)ip6h));
7000 
7001 	/*
7002 	 * We make it easy for IP to include our pseudo header
7003 	 * by putting our length in uh_checksum, modified (if
7004 	 * we have a routing header) by the checksum difference
7005 	 * between the ultimate destination and first hop addresses.
7006 	 * Note: UDP over IPv6 must always checksum the packet.
7007 	 */
7008 	csum += udph->uha_length;
7009 	csum = (csum & 0xFFFF) + (csum >> 16);
7010 	udph->uha_checksum = (uint16_t)csum;
7011 
7012 #ifdef _LITTLE_ENDIAN
7013 	ip_len = htons(ip_len);
7014 #endif
7015 	ip6h->ip6_plen = ip_len;
7016 
7017 	if (DB_TYPE(mp) != M_DATA) {
7018 		ASSERT(mp != mp1);
7019 		freeb(mp);
7020 	}
7021 
7022 	/* mp has been consumed and we'll return success */
7023 	ASSERT(*error == 0);
7024 	mp = NULL;
7025 
7026 	/* We're done. Pass the packet to IP */
7027 	BUMP_MIB(&udp_mib, udpOutDatagrams);
7028 	ip_output_v6(connp, mp1, q, IP_WPUT);
7029 
7030 done:
7031 	if (*error != 0) {
7032 		ASSERT(mp != NULL);
7033 		BUMP_MIB(&udp_mib, udpOutErrors);
7034 	}
7035 	return (mp);
7036 }
7037 
7038 static void
7039 udp_wput_other(queue_t *q, mblk_t *mp)
7040 {
7041 	uchar_t	*rptr = mp->b_rptr;
7042 	struct datab *db;
7043 	struct iocblk *iocp;
7044 	cred_t	*cr;
7045 	conn_t	*connp = Q_TO_CONN(q);
7046 	udp_t	*udp = connp->conn_udp;
7047 
7048 	TRACE_1(TR_FAC_UDP, TR_UDP_WPUT_OTHER_START,
7049 		"udp_wput_other_start: q %p", q);
7050 
7051 	db = mp->b_datap;
7052 
7053 	cr = DB_CREDDEF(mp, connp->conn_cred);
7054 
7055 	switch (db->db_type) {
7056 	case M_PROTO:
7057 	case M_PCPROTO:
7058 		if (mp->b_wptr - rptr < sizeof (t_scalar_t)) {
7059 			freemsg(mp);
7060 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7061 				"udp_wput_other_end: q %p (%S)",
7062 				q, "protoshort");
7063 			return;
7064 		}
7065 		switch (((t_primp_t)rptr)->type) {
7066 		case T_ADDR_REQ:
7067 			udp_addr_req(q, mp);
7068 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7069 				"udp_wput_other_end: q %p (%S)", q, "addrreq");
7070 			return;
7071 		case O_T_BIND_REQ:
7072 		case T_BIND_REQ:
7073 			udp_bind(q, mp);
7074 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7075 				"udp_wput_other_end: q %p (%S)", q, "bindreq");
7076 			return;
7077 		case T_CONN_REQ:
7078 			udp_connect(q, mp);
7079 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7080 				"udp_wput_other_end: q %p (%S)", q, "connreq");
7081 			return;
7082 		case T_CAPABILITY_REQ:
7083 			udp_capability_req(q, mp);
7084 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7085 				"udp_wput_other_end: q %p (%S)", q, "capabreq");
7086 			return;
7087 		case T_INFO_REQ:
7088 			udp_info_req(q, mp);
7089 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7090 				"udp_wput_other_end: q %p (%S)", q, "inforeq");
7091 			return;
7092 		case T_UNITDATA_REQ:
7093 			/*
7094 			 * If a T_UNITDATA_REQ gets here, the address must
7095 			 * be bad.  Valid T_UNITDATA_REQs are handled
7096 			 * in udp_wput.
7097 			 */
7098 			udp_ud_err(q, mp, NULL, 0, EADDRNOTAVAIL);
7099 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7100 				"udp_wput_other_end: q %p (%S)",
7101 				q, "unitdatareq");
7102 			return;
7103 		case T_UNBIND_REQ:
7104 			udp_unbind(q, mp);
7105 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7106 			    "udp_wput_other_end: q %p (%S)", q, "unbindreq");
7107 			return;
7108 		case T_SVR4_OPTMGMT_REQ:
7109 			if (!snmpcom_req(q, mp, udp_snmp_set, udp_snmp_get, cr))
7110 				/*
7111 				 * Use upper queue for option processing in
7112 				 * case the request is not handled at this
7113 				 * level and needs to be passed down to IP.
7114 				 */
7115 				(void) svr4_optcom_req(_WR(UDP_RD(q)),
7116 				    mp, cr, &udp_opt_obj);
7117 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7118 			    "udp_wput_other_end: q %p (%S)",
7119 			    q, "optmgmtreq");
7120 			return;
7121 
7122 		case T_OPTMGMT_REQ:
7123 			/*
7124 			 * Use upper queue for option processing in
7125 			 * case the request is not handled at this
7126 			 * level and needs to be passed down to IP.
7127 			 */
7128 			(void) tpi_optcom_req(_WR(UDP_RD(q)),
7129 			    mp, cr, &udp_opt_obj);
7130 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7131 				"udp_wput_other_end: q %p (%S)",
7132 				q, "optmgmtreq");
7133 			return;
7134 
7135 		case T_DISCON_REQ:
7136 			udp_disconnect(q, mp);
7137 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7138 				"udp_wput_other_end: q %p (%S)",
7139 				q, "disconreq");
7140 			return;
7141 
7142 		/* The following TPI message is not supported by udp. */
7143 		case O_T_CONN_RES:
7144 		case T_CONN_RES:
7145 			udp_err_ack(q, mp, TNOTSUPPORT, 0);
7146 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7147 				"udp_wput_other_end: q %p (%S)",
7148 				q, "connres/disconreq");
7149 			return;
7150 
7151 		/* The following 3 TPI messages are illegal for udp. */
7152 		case T_DATA_REQ:
7153 		case T_EXDATA_REQ:
7154 		case T_ORDREL_REQ:
7155 			udp_err_ack(q, mp, TNOTSUPPORT, 0);
7156 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7157 				"udp_wput_other_end: q %p (%S)",
7158 				q, "data/exdata/ordrel");
7159 			return;
7160 		default:
7161 			break;
7162 		}
7163 		break;
7164 	case M_FLUSH:
7165 		if (*rptr & FLUSHW)
7166 			flushq(q, FLUSHDATA);
7167 		break;
7168 	case M_IOCTL:
7169 		iocp = (struct iocblk *)mp->b_rptr;
7170 		switch (iocp->ioc_cmd) {
7171 		case TI_GETPEERNAME:
7172 			if (udp->udp_state != TS_DATA_XFER) {
7173 				/*
7174 				 * If a default destination address has not
7175 				 * been associated with the stream, then we
7176 				 * don't know the peer's name.
7177 				 */
7178 				iocp->ioc_error = ENOTCONN;
7179 				iocp->ioc_count = 0;
7180 				mp->b_datap->db_type = M_IOCACK;
7181 				putnext(UDP_RD(q), mp);
7182 				TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7183 					"udp_wput_other_end: q %p (%S)",
7184 					q, "getpeername");
7185 				return;
7186 			}
7187 			/* FALLTHRU */
7188 		case TI_GETMYNAME: {
7189 			/*
7190 			 * For TI_GETPEERNAME and TI_GETMYNAME, we first
7191 			 * need to copyin the user's strbuf structure.
7192 			 * Processing will continue in the M_IOCDATA case
7193 			 * below.
7194 			 */
7195 			mi_copyin(q, mp, NULL,
7196 			    SIZEOF_STRUCT(strbuf, iocp->ioc_flag));
7197 			TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7198 				"udp_wput_other_end: q %p (%S)",
7199 				q, "getmyname");
7200 			return;
7201 			}
7202 		case ND_SET:
7203 			/* nd_getset performs the necessary checking */
7204 		case ND_GET:
7205 			if (nd_getset(q, udp_g_nd, mp)) {
7206 				putnext(UDP_RD(q), mp);
7207 				TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7208 					"udp_wput_other_end: q %p (%S)",
7209 					q, "get");
7210 				return;
7211 			}
7212 			break;
7213 		case _SIOCSOCKFALLBACK:
7214 			/*
7215 			 * Either sockmod is about to be popped and the
7216 			 * socket would now be treated as a plain stream,
7217 			 * or a module is about to be pushed so we could
7218 			 * no longer use read-side synchronous stream.
7219 			 * Drain any queued data and disable direct sockfs
7220 			 * interface from now on.
7221 			 */
7222 			if (!udp->udp_issocket) {
7223 				DB_TYPE(mp) = M_IOCNAK;
7224 				iocp->ioc_error = EINVAL;
7225 			} else {
7226 				udp->udp_issocket = B_FALSE;
7227 				if (udp->udp_direct_sockfs) {
7228 					/*
7229 					 * Disable read-side synchronous
7230 					 * stream interface and drain any
7231 					 * queued data.
7232 					 */
7233 					udp_rcv_drain(UDP_RD(q), udp,
7234 					    B_FALSE);
7235 					ASSERT(!udp->udp_direct_sockfs);
7236 					UDP_STAT(udp_sock_fallback);
7237 				}
7238 				DB_TYPE(mp) = M_IOCACK;
7239 				iocp->ioc_error = 0;
7240 			}
7241 			iocp->ioc_count = 0;
7242 			iocp->ioc_rval = 0;
7243 			putnext(UDP_RD(q), mp);
7244 			return;
7245 		default:
7246 			break;
7247 		}
7248 		break;
7249 	case M_IOCDATA:
7250 		udp_wput_iocdata(q, mp);
7251 		TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7252 			"udp_wput_other_end: q %p (%S)", q, "iocdata");
7253 		return;
7254 	default:
7255 		/* Unrecognized messages are passed through without change. */
7256 		break;
7257 	}
7258 	TRACE_2(TR_FAC_UDP, TR_UDP_WPUT_OTHER_END,
7259 		"udp_wput_other_end: q %p (%S)", q, "end");
7260 	ip_output(connp, mp, q, IP_WPUT);
7261 }
7262 
7263 /* ARGSUSED */
7264 static void
7265 udp_wput_other_wrapper(void *arg, mblk_t *mp, void *arg2)
7266 {
7267 	udp_wput_other(((conn_t *)arg)->conn_wq, mp);
7268 	udp_exit((conn_t *)arg);
7269 }
7270 
7271 /*
7272  * udp_wput_iocdata is called by udp_wput_other to handle all M_IOCDATA
7273  * messages.
7274  */
7275 static void
7276 udp_wput_iocdata(queue_t *q, mblk_t *mp)
7277 {
7278 	mblk_t	*mp1;
7279 	STRUCT_HANDLE(strbuf, sb);
7280 	uint16_t port;
7281 	in6_addr_t	v6addr;
7282 	ipaddr_t	v4addr;
7283 	uint32_t	flowinfo = 0;
7284 	int		addrlen;
7285 	udp_t		*udp = Q_TO_UDP(q);
7286 
7287 	/* Make sure it is one of ours. */
7288 	switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
7289 	case TI_GETMYNAME:
7290 	case TI_GETPEERNAME:
7291 		break;
7292 	default:
7293 		ip_output(Q_TO_CONN(q), mp, q, IP_WPUT);
7294 		return;
7295 	}
7296 
7297 	q = WR(UDP_RD(q));
7298 	switch (mi_copy_state(q, mp, &mp1)) {
7299 	case -1:
7300 		return;
7301 	case MI_COPY_CASE(MI_COPY_IN, 1):
7302 		break;
7303 	case MI_COPY_CASE(MI_COPY_OUT, 1):
7304 		/*
7305 		 * The address has been copied out, so now
7306 		 * copyout the strbuf.
7307 		 */
7308 		mi_copyout(q, mp);
7309 		return;
7310 	case MI_COPY_CASE(MI_COPY_OUT, 2):
7311 		/*
7312 		 * The address and strbuf have been copied out.
7313 		 * We're done, so just acknowledge the original
7314 		 * M_IOCTL.
7315 		 */
7316 		mi_copy_done(q, mp, 0);
7317 		return;
7318 	default:
7319 		/*
7320 		 * Something strange has happened, so acknowledge
7321 		 * the original M_IOCTL with an EPROTO error.
7322 		 */
7323 		mi_copy_done(q, mp, EPROTO);
7324 		return;
7325 	}
7326 
7327 	/*
7328 	 * Now we have the strbuf structure for TI_GETMYNAME
7329 	 * and TI_GETPEERNAME.  Next we copyout the requested
7330 	 * address and then we'll copyout the strbuf.
7331 	 */
7332 	STRUCT_SET_HANDLE(sb, ((struct iocblk *)mp->b_rptr)->ioc_flag,
7333 	    (void *)mp1->b_rptr);
7334 	if (udp->udp_family == AF_INET)
7335 		addrlen = sizeof (sin_t);
7336 	else
7337 		addrlen = sizeof (sin6_t);
7338 
7339 	if (STRUCT_FGET(sb, maxlen) < addrlen) {
7340 		mi_copy_done(q, mp, EINVAL);
7341 		return;
7342 	}
7343 	switch (((struct iocblk *)mp->b_rptr)->ioc_cmd) {
7344 	case TI_GETMYNAME:
7345 		if (udp->udp_family == AF_INET) {
7346 			ASSERT(udp->udp_ipversion == IPV4_VERSION);
7347 			if (!IN6_IS_ADDR_V4MAPPED_ANY(&udp->udp_v6src) &&
7348 			    !IN6_IS_ADDR_UNSPECIFIED(&udp->udp_v6src)) {
7349 				v4addr = V4_PART_OF_V6(udp->udp_v6src);
7350 			} else {
7351 				/*
7352 				 * INADDR_ANY
7353 				 * udp_v6src is not set, we might be bound to
7354 				 * broadcast/multicast. Use udp_bound_v6src as
7355 				 * local address instead (that could
7356 				 * also still be INADDR_ANY)
7357 				 */
7358 				v4addr = V4_PART_OF_V6(udp->udp_bound_v6src);
7359 			}
7360 		} else {
7361 			/* udp->udp_family == AF_INET6 */
7362 			if (!IN6_IS_ADDR_UNSPECIFIED(&udp->udp_v6src)) {
7363 				v6addr = udp->udp_v6src;
7364 			} else {
7365 				/*
7366 				 * UNSPECIFIED
7367 				 * udp_v6src is not set, we might be bound to
7368 				 * broadcast/multicast. Use udp_bound_v6src as
7369 				 * local address instead (that could
7370 				 * also still be UNSPECIFIED)
7371 				 */
7372 				v6addr = udp->udp_bound_v6src;
7373 			}
7374 		}
7375 		port = udp->udp_port;
7376 		break;
7377 	case TI_GETPEERNAME:
7378 		if (udp->udp_state != TS_DATA_XFER) {
7379 			mi_copy_done(q, mp, ENOTCONN);
7380 			return;
7381 		}
7382 		if (udp->udp_family == AF_INET) {
7383 			ASSERT(udp->udp_ipversion == IPV4_VERSION);
7384 			v4addr = V4_PART_OF_V6(udp->udp_v6dst);
7385 		} else {
7386 			/* udp->udp_family == AF_INET6) */
7387 			v6addr = udp->udp_v6dst;
7388 			flowinfo = udp->udp_flowinfo;
7389 		}
7390 		port = udp->udp_dstport;
7391 		break;
7392 	default:
7393 		mi_copy_done(q, mp, EPROTO);
7394 		return;
7395 	}
7396 	mp1 = mi_copyout_alloc(q, mp, STRUCT_FGETP(sb, buf), addrlen, B_TRUE);
7397 	if (!mp1)
7398 		return;
7399 
7400 	if (udp->udp_family == AF_INET) {
7401 		sin_t *sin;
7402 
7403 		STRUCT_FSET(sb, len, (int)sizeof (sin_t));
7404 		sin = (sin_t *)mp1->b_rptr;
7405 		mp1->b_wptr = (uchar_t *)&sin[1];
7406 		*sin = sin_null;
7407 		sin->sin_family = AF_INET;
7408 		sin->sin_addr.s_addr = v4addr;
7409 		sin->sin_port = port;
7410 	} else {
7411 		/* udp->udp_family == AF_INET6 */
7412 		sin6_t *sin6;
7413 
7414 		STRUCT_FSET(sb, len, (int)sizeof (sin6_t));
7415 		sin6 = (sin6_t *)mp1->b_rptr;
7416 		mp1->b_wptr = (uchar_t *)&sin6[1];
7417 		*sin6 = sin6_null;
7418 		sin6->sin6_family = AF_INET6;
7419 		sin6->sin6_flowinfo = flowinfo;
7420 		sin6->sin6_addr = v6addr;
7421 		sin6->sin6_port = port;
7422 	}
7423 	/* Copy out the address */
7424 	mi_copyout(q, mp);
7425 }
7426 
7427 
7428 static int
7429 udp_unitdata_opt_process(queue_t *q, mblk_t *mp, int *errorp,
7430     void *thisdg_attrs)
7431 {
7432 	struct T_unitdata_req *udreqp;
7433 	int is_absreq_failure;
7434 	cred_t *cr;
7435 	conn_t	*connp = Q_TO_CONN(q);
7436 
7437 	ASSERT(((t_primp_t)mp->b_rptr)->type);
7438 
7439 	cr = DB_CREDDEF(mp, connp->conn_cred);
7440 
7441 	udreqp = (struct T_unitdata_req *)mp->b_rptr;
7442 	*errorp = 0;
7443 
7444 	/*
7445 	 * Use upper queue for option processing since the callback
7446 	 * routines expect to be called in UDP instance instead of IP.
7447 	 */
7448 	*errorp = tpi_optcom_buf(_WR(UDP_RD(q)), mp, &udreqp->OPT_length,
7449 	    udreqp->OPT_offset, cr, &udp_opt_obj,
7450 	    thisdg_attrs, &is_absreq_failure);
7451 
7452 	if (*errorp != 0) {
7453 		/*
7454 		 * Note: No special action needed in this
7455 		 * module for "is_absreq_failure"
7456 		 */
7457 		return (-1);		/* failure */
7458 	}
7459 	ASSERT(is_absreq_failure == 0);
7460 	return (0);	/* success */
7461 }
7462 
7463 void
7464 udp_ddi_init(void)
7465 {
7466 	int i;
7467 
7468 	UDP6_MAJ = ddi_name_to_major(UDP6);
7469 
7470 	udp_max_optsize = optcom_max_optsize(udp_opt_obj.odb_opt_des_arr,
7471 	    udp_opt_obj.odb_opt_arr_cnt);
7472 
7473 	if (udp_bind_fanout_size & (udp_bind_fanout_size - 1)) {
7474 		/* Not a power of two. Round up to nearest power of two */
7475 		for (i = 0; i < 31; i++) {
7476 			if (udp_bind_fanout_size < (1 << i))
7477 				break;
7478 		}
7479 		udp_bind_fanout_size = 1 << i;
7480 	}
7481 	udp_bind_fanout = kmem_zalloc(udp_bind_fanout_size *
7482 	    sizeof (udp_fanout_t), KM_SLEEP);
7483 	for (i = 0; i < udp_bind_fanout_size; i++) {
7484 		mutex_init(&udp_bind_fanout[i].uf_lock, NULL, MUTEX_DEFAULT,
7485 		    NULL);
7486 	}
7487 	(void) udp_param_register(udp_param_arr, A_CNT(udp_param_arr));
7488 
7489 	udp_kstat_init();
7490 
7491 	udp_cache = kmem_cache_create("udp_cache", sizeof (udp_t),
7492 	    CACHE_ALIGN_SIZE, NULL, NULL, NULL, NULL, NULL, 0);
7493 }
7494 
7495 void
7496 udp_ddi_destroy(void)
7497 {
7498 	int i;
7499 
7500 	nd_free(&udp_g_nd);
7501 
7502 	for (i = 0; i < udp_bind_fanout_size; i++) {
7503 		mutex_destroy(&udp_bind_fanout[i].uf_lock);
7504 	}
7505 
7506 	kmem_free(udp_bind_fanout, udp_bind_fanout_size *
7507 	    sizeof (udp_fanout_t));
7508 
7509 	udp_kstat_fini();
7510 
7511 	kmem_cache_destroy(udp_cache);
7512 }
7513 
7514 static void
7515 udp_kstat_init(void)
7516 {
7517 	udp_named_kstat_t template = {
7518 		{ "inDatagrams",	KSTAT_DATA_UINT32, 0 },
7519 		{ "inErrors",		KSTAT_DATA_UINT32, 0 },
7520 		{ "outDatagrams",	KSTAT_DATA_UINT32, 0 },
7521 		{ "entrySize",		KSTAT_DATA_INT32, 0 },
7522 		{ "entry6Size",		KSTAT_DATA_INT32, 0 },
7523 		{ "outErrors",		KSTAT_DATA_UINT32, 0 },
7524 	};
7525 
7526 	udp_mibkp = kstat_create(UDP_MOD_NAME, 0, UDP_MOD_NAME,
7527 	    "mib2", KSTAT_TYPE_NAMED, NUM_OF_FIELDS(udp_named_kstat_t), 0);
7528 
7529 	if (udp_mibkp == NULL)
7530 		return;
7531 
7532 	template.entrySize.value.ui32 = sizeof (mib2_udpEntry_t);
7533 	template.entry6Size.value.ui32 = sizeof (mib2_udp6Entry_t);
7534 
7535 	bcopy(&template, udp_mibkp->ks_data, sizeof (template));
7536 
7537 	udp_mibkp->ks_update = udp_kstat_update;
7538 
7539 	kstat_install(udp_mibkp);
7540 
7541 	if ((udp_ksp = kstat_create(UDP_MOD_NAME, 0, "udpstat",
7542 	    "net", KSTAT_TYPE_NAMED,
7543 	    sizeof (udp_statistics) / sizeof (kstat_named_t),
7544 	    KSTAT_FLAG_VIRTUAL)) != NULL) {
7545 		udp_ksp->ks_data = &udp_statistics;
7546 		kstat_install(udp_ksp);
7547 	}
7548 }
7549 
7550 static void
7551 udp_kstat_fini(void)
7552 {
7553 	if (udp_ksp != NULL) {
7554 		kstat_delete(udp_ksp);
7555 		udp_ksp = NULL;
7556 	}
7557 	if (udp_mibkp != NULL) {
7558 		kstat_delete(udp_mibkp);
7559 		udp_mibkp = NULL;
7560 	}
7561 }
7562 
7563 static int
7564 udp_kstat_update(kstat_t *kp, int rw)
7565 {
7566 	udp_named_kstat_t *udpkp;
7567 
7568 	if ((kp == NULL) || (kp->ks_data == NULL))
7569 		return (EIO);
7570 
7571 	if (rw == KSTAT_WRITE)
7572 		return (EACCES);
7573 
7574 	udpkp = (udp_named_kstat_t *)kp->ks_data;
7575 
7576 	udpkp->inDatagrams.value.ui32 =	udp_mib.udpInDatagrams;
7577 	udpkp->inErrors.value.ui32 =	udp_mib.udpInErrors;
7578 	udpkp->outDatagrams.value.ui32 = udp_mib.udpOutDatagrams;
7579 	udpkp->outErrors.value.ui32 =	udp_mib.udpOutErrors;
7580 
7581 	return (0);
7582 }
7583 
7584 /* ARGSUSED */
7585 static void
7586 udp_rput(queue_t *q, mblk_t *mp)
7587 {
7588 	/*
7589 	 * We get here whenever we do qreply() from IP,
7590 	 * i.e as part of handlings ioctls, etc.
7591 	 */
7592 	putnext(q, mp);
7593 }
7594 
7595 /*
7596  * Read-side synchronous stream info entry point, called as a
7597  * result of handling certain STREAMS ioctl operations.
7598  */
7599 static int
7600 udp_rinfop(queue_t *q, infod_t *dp)
7601 {
7602 	mblk_t	*mp;
7603 	uint_t	cmd = dp->d_cmd;
7604 	int	res = 0;
7605 	int	error = 0;
7606 	udp_t	*udp = Q_TO_UDP(RD(UDP_WR(q)));
7607 	struct stdata *stp = STREAM(q);
7608 
7609 	mutex_enter(&udp->udp_drain_lock);
7610 	/* If shutdown on read has happened, return nothing */
7611 	mutex_enter(&stp->sd_lock);
7612 	if (stp->sd_flag & STREOF) {
7613 		mutex_exit(&stp->sd_lock);
7614 		goto done;
7615 	}
7616 	mutex_exit(&stp->sd_lock);
7617 
7618 	if ((mp = udp->udp_rcv_list_head) == NULL)
7619 		goto done;
7620 
7621 	ASSERT(DB_TYPE(mp) != M_DATA && mp->b_cont != NULL);
7622 
7623 	if (cmd & INFOD_COUNT) {
7624 		/*
7625 		 * Return the number of messages.
7626 		 */
7627 		dp->d_count += udp->udp_rcv_msgcnt;
7628 		res |= INFOD_COUNT;
7629 	}
7630 	if (cmd & INFOD_BYTES) {
7631 		/*
7632 		 * Return size of all data messages.
7633 		 */
7634 		dp->d_bytes += udp->udp_rcv_cnt;
7635 		res |= INFOD_BYTES;
7636 	}
7637 	if (cmd & INFOD_FIRSTBYTES) {
7638 		/*
7639 		 * Return size of first data message.
7640 		 */
7641 		dp->d_bytes = msgdsize(mp);
7642 		res |= INFOD_FIRSTBYTES;
7643 		dp->d_cmd &= ~INFOD_FIRSTBYTES;
7644 	}
7645 	if (cmd & INFOD_COPYOUT) {
7646 		mblk_t *mp1 = mp->b_cont;
7647 		int n;
7648 		/*
7649 		 * Return data contents of first message.
7650 		 */
7651 		ASSERT(DB_TYPE(mp1) == M_DATA);
7652 		while (mp1 != NULL && dp->d_uiop->uio_resid > 0) {
7653 			n = MIN(dp->d_uiop->uio_resid, MBLKL(mp1));
7654 			if (n != 0 && (error = uiomove((char *)mp1->b_rptr, n,
7655 			    UIO_READ, dp->d_uiop)) != 0) {
7656 				goto done;
7657 			}
7658 			mp1 = mp1->b_cont;
7659 		}
7660 		res |= INFOD_COPYOUT;
7661 		dp->d_cmd &= ~INFOD_COPYOUT;
7662 	}
7663 done:
7664 	mutex_exit(&udp->udp_drain_lock);
7665 
7666 	dp->d_res |= res;
7667 
7668 	return (error);
7669 }
7670 
7671 /*
7672  * Read-side synchronous stream entry point.  This is called as a result
7673  * of recv/read operation done at sockfs, and is guaranteed to execute
7674  * outside of the interrupt thread context.  It returns a single datagram
7675  * (b_cont chain of T_UNITDATA_IND plus data) to the upper layer.
7676  */
7677 static int
7678 udp_rrw(queue_t *q, struiod_t *dp)
7679 {
7680 	mblk_t	*mp;
7681 	udp_t	*udp = Q_TO_UDP(_RD(UDP_WR(q)));
7682 
7683 	/* We should never get here when we're in SNMP mode */
7684 	ASSERT(!(udp->udp_connp->conn_flags & IPCL_UDPMOD));
7685 
7686 	/*
7687 	 * Dequeue datagram from the head of the list and return
7688 	 * it to caller; also ensure that RSLEEP sd_wakeq flag is
7689 	 * set/cleared depending on whether or not there's data
7690 	 * remaining in the list.
7691 	 */
7692 	mutex_enter(&udp->udp_drain_lock);
7693 	if (!udp->udp_direct_sockfs) {
7694 		mutex_exit(&udp->udp_drain_lock);
7695 		UDP_STAT(udp_rrw_busy);
7696 		return (EBUSY);
7697 	}
7698 	if ((mp = udp->udp_rcv_list_head) != NULL) {
7699 		uint_t size = msgdsize(mp);
7700 
7701 		/* Last datagram in the list? */
7702 		if ((udp->udp_rcv_list_head = mp->b_next) == NULL)
7703 			udp->udp_rcv_list_tail = NULL;
7704 		mp->b_next = NULL;
7705 
7706 		udp->udp_rcv_cnt -= size;
7707 		udp->udp_rcv_msgcnt--;
7708 		UDP_STAT(udp_rrw_msgcnt);
7709 
7710 		/* No longer flow-controlling? */
7711 		if (udp->udp_rcv_cnt < udp->udp_rcv_hiwat &&
7712 		    udp->udp_rcv_msgcnt < udp->udp_rcv_hiwat)
7713 			udp->udp_drain_qfull = B_FALSE;
7714 	}
7715 	if (udp->udp_rcv_list_head == NULL) {
7716 		/*
7717 		 * Either we just dequeued the last datagram or
7718 		 * we get here from sockfs and have nothing to
7719 		 * return; in this case clear RSLEEP.
7720 		 */
7721 		ASSERT(udp->udp_rcv_cnt == 0);
7722 		ASSERT(udp->udp_rcv_msgcnt == 0);
7723 		ASSERT(udp->udp_rcv_list_tail == NULL);
7724 		STR_WAKEUP_CLEAR(STREAM(q));
7725 	} else {
7726 		/*
7727 		 * More data follows; we need udp_rrw() to be
7728 		 * called in future to pick up the rest.
7729 		 */
7730 		STR_WAKEUP_SET(STREAM(q));
7731 	}
7732 	mutex_exit(&udp->udp_drain_lock);
7733 	dp->d_mp = mp;
7734 	return (0);
7735 }
7736 
7737 /*
7738  * Enqueue a completely-built T_UNITDATA_IND message into the receive
7739  * list; this is typically executed within the interrupt thread context
7740  * and so we do things as quickly as possible.
7741  */
7742 static void
7743 udp_rcv_enqueue(queue_t *q, udp_t *udp, mblk_t *mp, uint_t pkt_len)
7744 {
7745 	ASSERT(q == RD(q));
7746 	ASSERT(pkt_len == msgdsize(mp));
7747 	ASSERT(mp->b_next == NULL && mp->b_cont != NULL);
7748 	ASSERT(DB_TYPE(mp) == M_PROTO && DB_TYPE(mp->b_cont) == M_DATA);
7749 	ASSERT(MBLKL(mp) >= sizeof (struct T_unitdata_ind));
7750 
7751 	mutex_enter(&udp->udp_drain_lock);
7752 	/*
7753 	 * Wake up and signal the receiving app; it is okay to do this
7754 	 * before enqueueing the mp because we are holding the drain lock.
7755 	 * One of the advantages of synchronous stream is the ability for
7756 	 * us to find out when the application performs a read on the
7757 	 * socket by way of udp_rrw() entry point being called.  We need
7758 	 * to generate SIGPOLL/SIGIO for each received data in the case
7759 	 * of asynchronous socket just as in the strrput() case.  However,
7760 	 * we only wake the application up when necessary, i.e. during the
7761 	 * first enqueue.  When udp_rrw() is called, we send up a single
7762 	 * datagram upstream and call STR_WAKEUP_SET() again when there
7763 	 * are still data remaining in our receive queue.
7764 	 */
7765 	if (udp->udp_rcv_list_head == NULL) {
7766 		STR_WAKEUP_SET(STREAM(q));
7767 		udp->udp_rcv_list_head = mp;
7768 	} else {
7769 		udp->udp_rcv_list_tail->b_next = mp;
7770 	}
7771 	udp->udp_rcv_list_tail = mp;
7772 	udp->udp_rcv_cnt += pkt_len;
7773 	udp->udp_rcv_msgcnt++;
7774 
7775 	/* Need to flow-control? */
7776 	if (udp->udp_rcv_cnt >= udp->udp_rcv_hiwat ||
7777 	    udp->udp_rcv_msgcnt >= udp->udp_rcv_hiwat)
7778 		udp->udp_drain_qfull = B_TRUE;
7779 
7780 	/* Update poll events and send SIGPOLL/SIGIO if necessary */
7781 	STR_SENDSIG(STREAM(q));
7782 	mutex_exit(&udp->udp_drain_lock);
7783 }
7784 
7785 /*
7786  * Drain the contents of receive list to the module upstream; we do
7787  * this during close or when we fallback to the slow mode due to
7788  * sockmod being popped or a module being pushed on top of us.
7789  */
7790 static void
7791 udp_rcv_drain(queue_t *q, udp_t *udp, boolean_t closing)
7792 {
7793 	mblk_t *mp;
7794 
7795 	ASSERT(q == RD(q));
7796 
7797 	mutex_enter(&udp->udp_drain_lock);
7798 	/*
7799 	 * There is no race with a concurrent udp_input() sending
7800 	 * up packets using putnext() after we have cleared the
7801 	 * udp_direct_sockfs flag but before we have completed
7802 	 * sending up the packets in udp_rcv_list, since we are
7803 	 * either a writer or we have quiesced the conn.
7804 	 */
7805 	udp->udp_direct_sockfs = B_FALSE;
7806 	mutex_exit(&udp->udp_drain_lock);
7807 
7808 	if (udp->udp_rcv_list_head != NULL)
7809 		UDP_STAT(udp_drain);
7810 
7811 	/*
7812 	 * Send up everything via putnext(); note here that we
7813 	 * don't need the udp_drain_lock to protect us since
7814 	 * nothing can enter udp_rrw() and that we currently
7815 	 * have exclusive access to this udp.
7816 	 */
7817 	while ((mp = udp->udp_rcv_list_head) != NULL) {
7818 		udp->udp_rcv_list_head = mp->b_next;
7819 		mp->b_next = NULL;
7820 		udp->udp_rcv_cnt -= msgdsize(mp);
7821 		udp->udp_rcv_msgcnt--;
7822 		if (closing) {
7823 			freemsg(mp);
7824 		} else {
7825 			putnext(q, mp);
7826 		}
7827 	}
7828 	ASSERT(udp->udp_rcv_cnt == 0);
7829 	ASSERT(udp->udp_rcv_msgcnt == 0);
7830 	ASSERT(udp->udp_rcv_list_head == NULL);
7831 	udp->udp_rcv_list_tail = NULL;
7832 	udp->udp_drain_qfull = B_FALSE;
7833 }
7834 
7835 static size_t
7836 udp_set_rcv_hiwat(udp_t *udp, size_t size)
7837 {
7838 	/* We add a bit of extra buffering */
7839 	size += size >> 1;
7840 	if (size > udp_max_buf)
7841 		size = udp_max_buf;
7842 
7843 	udp->udp_rcv_hiwat = size;
7844 	return (size);
7845 }
7846 
7847 /*
7848  * Little helper for IPsec's NAT-T processing.
7849  */
7850 boolean_t
7851 udp_compute_checksum(void)
7852 {
7853 	return (udp_do_checksum);
7854 }
7855