xref: /illumos-gate/usr/src/uts/common/inet/ip_ndp.h (revision b1e2e3fb17324e9ddf43db264a0c64da7756d9e6)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef	_INET_IP_NDP_H
27 #define	_INET_IP_NDP_H
28 
29 #include <sys/mutex.h>
30 #include <sys/stream.h>
31 #include <netinet/in.h>
32 #include <netinet/icmp6.h>
33 #include <inet/ip.h>
34 #include <inet/ip2mac.h>
35 
36 /*
37  * Internal definitions for the kernel implementation of the IPv6
38  * Neighbor Discovery Protocol (NDP) and Address Resolution Protocol (ARP).
39  */
40 
41 #ifdef	__cplusplus
42 extern "C" {
43 #endif
44 
45 #ifdef _KERNEL
46 #define	NCE_TABLE_SIZE	256
47 /*
48  * callbacks set up with ip2mac interface, waiting for result
49  * of neighbor resolution.
50  */
51 typedef struct ncec_cb_s {
52 	list_node_t		ncec_cb_node;	/* next entry in list */
53 	void			*ncec_cb_id;
54 	uint32_t		ncec_cb_flags;
55 	ip2mac_callback_t	*ncec_cb_func;
56 	void			*ncec_cb_arg;
57 } ncec_cb_t;
58 
59 #define	NCE_CB_DISPATCHED	0x00000001
60 
61 /*
62  * Core information tracking Neighbor Reachability is tracked in the
63  * ncec_s/ncec_t. The information contained in the ncec_t does not contain
64  * any link-specific details other than the pointer to the ill_t itself.
65  * The link-specific information is tracked in the nce_t structure.
66  */
67 struct ncec_s {
68 	struct	ncec_s	*ncec_next;	/* Hash chain next pointer */
69 	struct	ncec_s	**ncec_ptpn;	/* Pointer to previous next */
70 	struct	ill_s	*ncec_ill;	/* Associated ill */
71 	uint16_t	ncec_flags;	/* See below */
72 	uint16_t	ncec_state;	/* See reachability states in if.h */
73 	int16_t		ncec_pcnt;	/* Probe counter */
74 	uint16_t	ncec_rcnt;	/* Retransmit counter */
75 	in6_addr_t	ncec_addr;	/* address of the nighbor */
76 	uchar_t		*ncec_lladdr;
77 	mblk_t		*ncec_qd_mp;	/* Head outgoing queued packets */
78 	uint64_t	ncec_last;	/* Time last reachable in msec */
79 	uint32_t	ncec_refcnt;	/* ncec active usage count */
80 	kmutex_t	ncec_lock;	/* See comments on top for what */
81 					/* this field protects */
82 	int		ncec_unsolicit_count; /* Unsolicited Adv count */
83 	timeout_id_t	ncec_timeout_id;
84 	uchar_t		ncec_ipversion;	/* IPv4(ARP)/IPv6(NDP) version */
85 	uint_t		ncec_defense_count;	/* number of NDP conflicts */
86 	uint_t		ncec_last_time_defended; /* last time defended (secs) */
87 	uint64_t	ncec_init_time; /* time when it was set to ND_INITIAL */
88 	boolean_t	ncec_trace_disable;	/* True when alloc fails */
89 	/*
90 	 * interval to keep track of DAD probes.
91 	 */
92 	clock_t		ncec_xmit_interval;
93 	ip_stack_t	*ncec_ipst;	/* Does not have a netstack_hold */
94 	list_t		ncec_cb;	/* callbacks waiting for resolution */
95 	uint_t		ncec_cb_walker_cnt;
96 	uint_t		ncec_nprobes;
97 	uint_t		ncec_lladdr_length;
98 };
99 
100 /*
101  * The nce_t list hangs off the ill_s and tracks information that depends
102  * on the underlying physical link. Thus when the ill goes down,
103  * the nce_t list has to be flushed. This is  done as part of ill_delete()
104  *
105  * When the fastpath ack comes back in ill_fastpath_ack we call
106  * nce_fastpath_update to update the nce_t. We never actually
107  * flush the fastpath list, which is kept as an index into the
108  * ncec_t structures.
109  *
110  * when we ndp_delete, we remove the nce entries pointing
111  * at the dying ncec from the ill_fastpath_list chain.
112  *
113  */
114 struct nce_s	{
115 	list_node_t	nce_node;
116 	ill_t		*nce_ill;
117 	boolean_t	nce_is_condemned;
118 	in6_addr_t	nce_addr;
119 	/*
120 	 * link-layer specific fields below
121 	 */
122 	mblk_t		*nce_dlur_mp;	/* DL_UNITDATA_REQ mp */
123 	mblk_t		*nce_fp_mp;	/* fast path mp */
124 	struct ncec_s	*nce_common;
125 	kmutex_t	nce_lock;
126 	uint32_t	nce_refcnt;
127 	uint_t		nce_ipif_cnt;	/* number of ipifs with the nce_addr */
128 					/* as their local address */
129 };
130 
131 /*
132  * The ndp_g_t structure contains protocol specific information needed
133  * to synchronize and manage neighbor cache entries for IPv4 and IPv6.
134  * There are 2 such structures, ips_ndp4 and ips_ndp6.
135  * ips_ndp6 contains the data structures needed for IPv6 Neighbor Discovery.
136  * ips_ndp4 contains the data structures for IPv4 ARP.
137  *
138  * Locking notes:
139  * ndp_g_lock protects neighbor cache tables access and
140  * insertion/removal of cache entries into/from these tables. The ncec_lock
141  * and nce_lock protect fields in the ncec_t and nce_t structures.
142  * Should there be a need to obtain nce[c]_lock and ndp_g_lock, ndp_g_lock is
143  * acquired first.
144  */
145 typedef	struct ndp_g_s {
146 	kmutex_t	ndp_g_lock;	/* Lock protecting  cache hash table */
147 	ncec_t		*nce_hash_tbl[NCE_TABLE_SIZE];
148 	int		ndp_g_walker; /* # of active thread walking hash list */
149 	boolean_t	ndp_g_walker_cleanup; /* true implies defer deletion. */
150 } ndp_g_t;
151 
152 /* ncec_flags  */
153 #define	NCE_F_MYADDR		0x1	/* ipif exists for the ncec_addr */
154 #define	NCE_F_UNVERIFIED	0x2	/* DAD in progress. */
155 #define	NCE_F_ISROUTER		0x4
156 #define	NCE_F_FAST		0x8
157 
158 /*
159  * NCE_F_NONUD is used to disable IPv6 Neighbor Unreachability Detection or
160  * IPv4 aging and maps to the ATF_PERM flag for arp(1m)
161  */
162 #define	NCE_F_NONUD		0x10
163 
164 #define	NCE_F_ANYCAST		0x20
165 #define	NCE_F_CONDEMNED		0x40
166 #define	NCE_F_UNSOL_ADV		0x80
167 #define	NCE_F_BCAST		0x100
168 #define	NCE_F_MCAST		0x200
169 
170 /*
171  * NCE_F_PUBLISH is set for all ARP/ND entries that we announce. This
172  * includes locally configured addresses as well as those that we proxy for.
173  */
174 #define	NCE_F_PUBLISH		0x400
175 
176 /*
177  * NCE_F_AUTHORITY is set for any address that we have authoritatitve
178  * information for. This includes locally configured addresses as well
179  * as statically configured arp entries that are set up using the "permanent"
180  * option described in arp(1m). The NCE_F_AUTHORITY asserts that we would
181  * reject any updates for that nce's (host, link-layer-address) information
182  */
183 #define	NCE_F_AUTHORITY		0x800
184 
185 #define	NCE_F_DELAYED		0x1000 /* rescheduled on dad_defend_rate */
186 #define	NCE_F_STATIC		0x2000
187 
188 /* State REACHABLE, STALE, DELAY or PROBE */
189 #define	NCE_ISREACHABLE(ncec)			\
190 	(((((ncec)->ncec_state) >= ND_REACHABLE) &&	\
191 	((ncec)->ncec_state) <= ND_PROBE))
192 
193 #define	NCE_ISCONDEMNED(ncec)	((ncec)->ncec_flags & NCE_F_CONDEMNED)
194 
195 /* NDP flags set in SOL/ADV requests */
196 #define	NDP_UNICAST		0x1
197 #define	NDP_ISROUTER		0x2
198 #define	NDP_SOLICITED		0x4
199 #define	NDP_ORIDE		0x8
200 #define	NDP_PROBE		0x10
201 
202 /* Number of packets queued in NDP for a neighbor */
203 #define	ND_MAX_Q		4
204 
205 /*
206  * Structure for nce_update_hw_changed;
207  */
208 typedef struct {
209 	ipaddr_t hwm_addr;	/* IPv4 address */
210 	uint_t	hwm_hwlen;	/* Length of hardware address (may be 0) */
211 	uchar_t *hwm_hwaddr;	/* Pointer to new hardware address, if any */
212 	int	hwm_flags;
213 } nce_hw_map_t;
214 
215 /* When SAP is greater than zero address appears before SAP */
216 #define	NCE_LL_ADDR_OFFSET(ill)	(((ill)->ill_sap_length) < 0 ? \
217 	(sizeof (dl_unitdata_req_t)) : \
218 	((sizeof (dl_unitdata_req_t)) + (ABS((ill)->ill_sap_length))))
219 
220 #define	NCE_LL_SAP_OFFSET(ill) (((ill)->ill_sap_length) < 0 ? \
221 	((sizeof (dl_unitdata_req_t)) + ((ill)->ill_phys_addr_length)) : \
222 	(sizeof (dl_unitdata_req_t)))
223 
224 #define	NCE_MYADDR(ncec)	(((ncec)->ncec_flags & NCE_F_MYADDR) != 0)
225 
226 /*
227  * NCE_PUBLISH() identifies the addresses that we are publishing. This
228  * includes locally configured address (NCE_MYADDR()) as well as those that
229  * we are proxying.
230  */
231 #define	NCE_PUBLISH(ncec) ((ncec->ncec_flags & NCE_F_PUBLISH) != 0)
232 
233 #ifdef _BIG_ENDIAN
234 #define	NCE_LL_SAP_COPY(ill, mp) \
235 	{ \
236 	size_t abs_sap_len = ABS((ill)->ill_sap_length); \
237 	if (abs_sap_len > 0) { \
238 		ASSERT(abs_sap_len <= sizeof (uint32_t)); \
239 		ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \
240 		    abs_sap_len <= ((mp)->b_wptr)); \
241 		bcopy((uint8_t *)&(ill)->ill_sap + sizeof (ill->ill_sap) - \
242 		    abs_sap_len, \
243 		    ((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \
244 		    abs_sap_len); \
245 	} \
246 	}
247 #else
248 #define	NCE_LL_SAP_COPY(ill, mp) \
249 	{ \
250 	size_t abs_sap_len = ABS((ill)->ill_sap_length); \
251 	if (abs_sap_len > 0) { \
252 		uint32_t abs_sap_len = ABS((ill)->ill_sap_length); \
253 		ASSERT(abs_sap_len <= sizeof (uint32_t)); \
254 		ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \
255 		    abs_sap_len <= ((mp)->b_wptr)); \
256 		bcopy(&((ill)->ill_sap), \
257 		((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \
258 		abs_sap_len); \
259 	} \
260 	}
261 #endif
262 
263 /*
264  * Exclusive-or the 6 bytes that are likely to contain the MAC
265  * address. Assumes table_size does not exceed 256.
266  * Assumes EUI-64 format for good hashing.
267  */
268 #define	NCE_ADDR_HASH_V6(addr, table_size)				\
269 	(((addr).s6_addr8[8] ^ (addr).s6_addr8[9] ^			\
270 	(addr).s6_addr8[10] ^ (addr).s6_addr8[13] ^			\
271 	(addr).s6_addr8[14] ^ (addr).s6_addr8[15]) % (table_size))
272 
273 /* NDP Cache Entry Hash Table */
274 #define	NCE_TABLE_SIZE	256
275 
276 typedef void (*ncec_walk_cb_t)(ncec_t *, void *);
277 
278 extern	void	ip_nce_reclaim(void *);
279 extern	void	ncec_delete(ncec_t *);
280 extern	void	ncec_delete_per_ill(ncec_t *, void *);
281 extern	void	nce_fastpath_update(ill_t *, mblk_t  *);
282 extern	nd_opt_hdr_t *ndp_get_option(nd_opt_hdr_t *, int, int);
283 extern	void	ncec_inactive(ncec_t *);
284 extern	void	ndp_input(mblk_t *, ip_recv_attr_t *);
285 extern	ncec_t	*ncec_lookup_illgrp_v6(ill_t *, const in6_addr_t *);
286 extern	ncec_t	*ncec_lookup_illgrp_v4(ill_t *, const in_addr_t *);
287 extern	nce_t	*nce_lookup_v4(ill_t *, const in_addr_t *);
288 extern	nce_t	*nce_lookup_v6(ill_t *, const in6_addr_t *);
289 extern	void	nce_make_unreachable(ncec_t *);
290 extern	mblk_t	*ndp_mcastreq(ill_t *, const in6_addr_t *, uint32_t, uint32_t,
291     mblk_t *);
292 extern  nce_t	*ndp_nce_init(ill_t *, const in6_addr_t *, int);
293 extern  void	nce_process(ncec_t *, uchar_t *, uint32_t, boolean_t);
294 extern	int	ndp_query(ill_t *, lif_nd_req_t *);
295 extern	int	ndp_sioc_update(ill_t *, lif_nd_req_t *);
296 extern	boolean_t	ndp_verify_optlen(nd_opt_hdr_t *, int);
297 extern	void	nce_timer(void *);
298 extern	void	ncec_walk(ill_t *, ncec_walk_cb_t, void *, ip_stack_t *);
299 extern	void	ncec_walk_common(ndp_g_t *, ill_t *, ncec_walk_cb_t,
300     void *, boolean_t);
301 extern	boolean_t	nce_restart_dad(ncec_t *);
302 extern	void	ndp_resolv_failed(ncec_t *);
303 extern	void	arp_resolv_failed(ncec_t *);
304 extern	void	nce_fastpath_list_delete(ill_t *, ncec_t *, list_t *);
305 extern	void	nce_queue_mp(ncec_t *, mblk_t *, boolean_t);
306 extern	void	nce_update_hw_changed(ncec_t *, void *);
307 extern	int	nce_lookup_then_add_v6(ill_t *, uchar_t *, uint_t,
308     const in6_addr_t *, uint16_t, uint16_t, nce_t **);
309 extern	int	nce_lookup_then_add_v4(ill_t *, uchar_t *, uint_t,
310     const in_addr_t *, uint16_t, uint16_t, nce_t **);
311 extern boolean_t nce_cmp_ll_addr(const ncec_t *, const uchar_t *, uint32_t);
312 extern void	nce_update(ncec_t *, uint16_t, uchar_t *);
313 extern nce_t   *nce_lookup_mapping(ill_t *, const in6_addr_t *);
314 
315 extern void	nce_restart_timer(ncec_t *, uint_t);
316 extern void	ncec_refrele(ncec_t *);
317 extern void	ncec_refhold(ncec_t *);
318 extern void	ncec_refrele_notr(ncec_t *);
319 extern void	ncec_refhold_notr(ncec_t *);
320 extern void	nce_resolv_ok(ncec_t *);
321 extern uint32_t	ndp_solicit(ncec_t *, in6_addr_t, ill_t *);
322 extern boolean_t ip_nce_conflict(mblk_t *, ip_recv_attr_t *, ncec_t *);
323 extern boolean_t ndp_announce(ncec_t *);
324 extern void	ip_nce_lookup_and_update(ipaddr_t *, ipif_t *, ip_stack_t *,
325     uchar_t *, int, int);
326 extern void	nce_refrele(nce_t *);
327 extern void	nce_refhold(nce_t *);
328 extern void	nce_delete(nce_t *);
329 extern void	nce_flush(ill_t *, boolean_t);
330 extern void	nce_walk(ill_t *, pfi_t, void *);
331 extern void	ip_ndp_resolve(struct ncec_s *);
332 extern void	ip_addr_recover(ipsq_t *, queue_t *, mblk_t *, void *);
333 
334 #ifdef DEBUG
335 extern	void	nce_trace_ref(ncec_t *);
336 extern	void	nce_untrace_ref(ncec_t *);
337 #endif
338 
339 #endif	/* _KERNEL */
340 
341 #ifdef	__cplusplus
342 }
343 #endif
344 
345 #endif	/* _INET_IP_NDP_H */
346