xref: /illumos-gate/usr/src/uts/common/inet/ip_ndp.h (revision 4de2612967d06c4fdbf524a62556a1e8118a006f)
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 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #ifndef	_INET_IP_NDP_H
28 #define	_INET_IP_NDP_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*
33  * Internal definitions for the kernel implementation of the IPv6
34  * Neighbor Discovery Protocol (NDP).
35  */
36 
37 #ifdef	__cplusplus
38 extern "C" {
39 #endif
40 
41 #ifdef _KERNEL
42 /*
43  * ndp_g_lock protects neighbor cache tables access and
44  * insertion/removal of cache entries into/from these tables.
45  * nce_lock protects nce_pcnt, nce_rcnt, nce_qd_mp nce_state,
46  * nce_res_mp, nce_refcnt and nce_last.
47  * nce_refcnt is incremented for every ire pointing to this nce and
48  * every time ndp_lookup() finds an nce.
49  * Should there be a need to obtain nce_lock and ndp_g_lock, ndp_g_lock is
50  * acquired first.
51  * To avoid becoming exclusive when deleting NCEs, ndp_walk() routine holds
52  * the ndp_g_lock (i.e global lock) and marks NCEs to be deleted with
53  * NCE_F_CONDEMNED.  When all active users of such NCEs are gone the walk
54  * routine passes a list for deletion to nce_ire_delete_list().
55  */
56 kmutex_t	ndp_g_lock; /* Lock protecting nighbor cache hash table */
57 /* NDP Cache Entry */
58 typedef struct nce_s {
59 	struct	nce_s	*nce_next;	/* Hash chain next pointer */
60 	struct	nce_s	**nce_ptpn;	/* Pointer to previous next */
61 	struct 	ill_s	*nce_ill;	/* Associated ill */
62 	uint16_t	nce_flags;	/* See below */
63 	uint16_t	nce_state;	/* See reachability states in if.h */
64 	int16_t		nce_pcnt;	/* Probe counter */
65 	uint16_t	nce_rcnt;	/* Retransmit counter */
66 	in6_addr_t	nce_addr;	/* address of the nighbor */
67 	in6_addr_t	nce_mask;	/* If not all ones, mask allows an */
68 	    /* entry  to respond to requests for a group of addresses, for */
69 	    /* instantance multicast addresses				   */
70 	in6_addr_t	nce_extract_mask; /* For mappings */
71 	uint32_t	nce_ll_extract_start;	/* For mappings */
72 #define	nce_first_mp_to_free	nce_fp_mp
73 	mblk_t		*nce_fp_mp;	/* link layer fast path mp */
74 	mblk_t		*nce_res_mp;	/* DL_UNITDATA_REQ or link layer mp */
75 	mblk_t		*nce_qd_mp;	/* Head outgoing queued packets */
76 #define	nce_last_mp_to_free	nce_qd_mp
77 	mblk_t		*nce_timer_mp;	/* NDP timer mblk */
78 	mblk_t		*nce_mp;	/* mblk we are in, last to be freed */
79 	uint64_t	nce_last;	/* Time last reachable in msec */
80 	uint32_t	nce_refcnt;	/* nce active usage count */
81 	kmutex_t	nce_lock;	/* See comments on top for what */
82 					/* this field protects */
83 	int		nce_unsolicit_count; /* Unsolicited Adv count */
84 	struct nce_s	*nce_fastpath;	/* for fastpath list */
85 	timeout_id_t	nce_timeout_id;
86 #ifdef NCE_DEBUG
87 	th_trace_t	*nce_trace[IP_TR_HASH_MAX];
88 	boolean_t	nce_trace_disable;	/* True when alloc fails */
89 #endif
90 } nce_t;
91 
92 /* nce_flags  */
93 #define	NCE_F_PERMANENT		0x1
94 #define	NCE_F_MAPPING		0x2
95 #define	NCE_F_ISROUTER		0x4
96 #define	NCE_F_PROXY		0x8
97 #define	NCE_F_NONUD		0x10
98 #define	NCE_F_ANYCAST		0x20
99 #define	NCE_F_CONDEMNED		0x40
100 #define	NCE_F_UNSOL_ADV		0x80
101 
102 #define	NCE_EXTERNAL_FLAGS_MASK \
103 	(NCE_F_PERMANENT | NCE_F_MAPPING | NCE_F_ISROUTER | NCE_F_NONUD | \
104 	NCE_F_ANYCAST | NCE_F_UNSOL_ADV)
105 
106 /* State REACHABLE, STALE, DELAY or PROBE */
107 #define	NCE_ISREACHABLE(nce)			\
108 	(((((nce)->nce_state) >= ND_REACHABLE) &&	\
109 	((nce)->nce_state) <= ND_PROBE))
110 
111 /* NDP flags set in SOL/ADV requests */
112 #define	NDP_UNICAST		0x1
113 #define	NDP_ISROUTER		0x2
114 #define	NDP_SOLICITED		0x4
115 #define	NDP_ORIDE		0x8
116 
117 /* Number of packets queued in NDP for a neighbor */
118 #define	ND_MAX_Q		4
119 
120 
121 #ifdef NCE_DEBUG
122 #define	NCE_TRACE_REF(nce)		nce_trace_ref(nce)
123 #define	NCE_UNTRACE_REF(nce)		nce_untrace_ref(nce)
124 #else
125 #define	NCE_TRACE_REF(nce)
126 #define	NCE_UNTRACE_REF(nce)
127 #endif
128 
129 #define	NCE_REFHOLD(nce) {		\
130 	mutex_enter(&(nce)->nce_lock);	\
131 	(nce)->nce_refcnt++;		\
132 	ASSERT((nce)->nce_refcnt != 0);	\
133 	NCE_TRACE_REF(nce);		\
134 	mutex_exit(&(nce)->nce_lock);	\
135 }
136 
137 #define	NCE_REFHOLD_NOTR(nce) {		\
138 	mutex_enter(&(nce)->nce_lock);	\
139 	(nce)->nce_refcnt++;		\
140 	ASSERT((nce)->nce_refcnt != 0);	\
141 	mutex_exit(&(nce)->nce_lock);	\
142 }
143 
144 #define	NCE_REFHOLD_LOCKED(nce) {		\
145 	ASSERT(MUTEX_HELD(&(nce)->nce_lock));	\
146 	(nce)->nce_refcnt++;			\
147 	NCE_TRACE_REF(nce);			\
148 }
149 
150 /* nce_inactive destroys the mutex thus no mutex_exit is needed */
151 #define	NCE_REFRELE(nce) {		\
152 	mutex_enter(&(nce)->nce_lock);	\
153 	NCE_UNTRACE_REF(nce);		\
154 	ASSERT((nce)->nce_refcnt != 0);	\
155 	if (--(nce)->nce_refcnt == 0)	\
156 		ndp_inactive(nce);	\
157 	else {				\
158 		mutex_exit(&(nce)->nce_lock);\
159 	}				\
160 }
161 
162 #define	NCE_REFRELE_NOTR(nce) {		\
163 	mutex_enter(&(nce)->nce_lock);	\
164 	ASSERT((nce)->nce_refcnt != 0);	\
165 	if (--(nce)->nce_refcnt == 0)	\
166 		ndp_inactive(nce);	\
167 	else {				\
168 		mutex_exit(&(nce)->nce_lock);\
169 	}				\
170 }
171 
172 #define	NDP_RESTART_TIMER(nce, ms) {	\
173 	ASSERT(!MUTEX_HELD(&(nce)->nce_lock));				\
174 	if ((nce)->nce_timeout_id != 0) {				\
175 		/* Ok to untimeout bad id. we don't hold a lock. */	\
176 		(void) untimeout((nce)->nce_timeout_id);		\
177 	}								\
178 	mutex_enter(&(nce)->nce_lock);					\
179 	/* Don't start the timer if the nce has been deleted */		\
180 	if (!((nce)->nce_flags & NCE_F_CONDEMNED)) 			\
181 		nce->nce_timeout_id = timeout(ndp_timer, nce, 		\
182 		    MSEC_TO_TICK(ms) == 0 ? 1 : MSEC_TO_TICK(ms));	\
183 	mutex_exit(&(nce)->nce_lock);					\
184 }
185 
186 /* Structure for ndp_cache_count() */
187 typedef struct {
188 	int	ncc_total;	/* Total number of NCEs */
189 	int	ncc_host;	/* NCE entries without R bit set */
190 } ncc_cache_count_t;
191 
192 /*
193  * Structure of ndp_cache_reclaim().  Each field is a fraction i.e. 1 means
194  * reclaim all, N means reclaim 1/Nth of all entries, 0 means reclaim none.
195  */
196 typedef struct {
197 	int	ncr_host;	/* Fraction for host entries */
198 } nce_cache_reclaim_t;
199 
200 /* When SAP is greater than zero address appears before SAP */
201 #define	NCE_LL_ADDR_OFFSET(ill)	(((ill)->ill_sap_length) < 0 ? \
202 	(sizeof (dl_unitdata_req_t)) : \
203 	((sizeof (dl_unitdata_req_t)) + (ABS((ill)->ill_sap_length))))
204 
205 #define	NCE_LL_SAP_OFFSET(ill) (((ill)->ill_sap_length) < 0 ? \
206 	((sizeof (dl_unitdata_req_t)) + ((ill)->ill_phys_addr_length)) : \
207 	(sizeof (dl_unitdata_req_t)))
208 
209 #ifdef _BIG_ENDIAN
210 #define	NCE_LL_SAP_COPY(ill, mp) \
211 	{ \
212 	size_t abs_sap_len = ABS((ill)->ill_sap_length); \
213 	if (abs_sap_len > 0) { \
214 		ASSERT(abs_sap_len <= sizeof (uint32_t)); \
215 		ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \
216 		    abs_sap_len <= ((mp)->b_wptr)); \
217 		bcopy((uint8_t *)&(ill)->ill_sap + sizeof (ill->ill_sap) - \
218 		    abs_sap_len, \
219 		    ((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \
220 		    abs_sap_len); \
221 	} \
222 	}
223 #else
224 #define	NCE_LL_SAP_COPY(ill, mp) \
225 	{ \
226 	size_t abs_sap_len = ABS((ill)->ill_sap_length); \
227 	if (abs_sap_len > 0) { \
228 		uint32_t abs_sap_len = ABS((ill)->ill_sap_length); \
229 		ASSERT(abs_sap_len <= sizeof (uint32_t)); \
230 		ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \
231 		    abs_sap_len <= ((mp)->b_wptr)); \
232 		bcopy(&((ill)->ill_sap), \
233 		((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \
234 		abs_sap_len); \
235 	} \
236 	}
237 #endif
238 
239 /*
240  * Exclusive-or the 6 bytes that are likely to contain the MAC
241  * address. Assumes table_size does not exceed 256.
242  * Assumes EUI-64 format for good hashing.
243  */
244 #define	NCE_ADDR_HASH_V6(addr, table_size)				\
245 	(((addr).s6_addr8[8] ^ (addr).s6_addr8[9] ^			\
246 	(addr).s6_addr8[10] ^ (addr).s6_addr8[13] ^			\
247 	(addr).s6_addr8[14] ^ (addr).s6_addr8[15]) % (table_size))
248 
249 extern	void	ndp_cache_count(nce_t *, char *);
250 extern	void	ndp_cache_reclaim(nce_t *, char *);
251 extern	void	ndp_delete(nce_t *);
252 extern	void	ndp_delete_per_ill(nce_t *, uchar_t *);
253 extern	void	ndp_fastpath_flush(nce_t *, char  *);
254 extern	boolean_t ndp_fastpath_update(nce_t *, void  *);
255 extern	nd_opt_hdr_t *ndp_get_option(nd_opt_hdr_t *, int, int);
256 extern	void	ndp_inactive(nce_t *);
257 extern	void	ndp_input(ill_t *, mblk_t *);
258 extern	nce_t	*ndp_lookup(ill_t *, const in6_addr_t *, boolean_t);
259 extern	int	ndp_lookup_then_add(ill_t *, uchar_t *, const in6_addr_t *,
260     const in6_addr_t *, const in6_addr_t *, uint32_t, uint16_t,
261     uint16_t, nce_t **);
262 extern	int	ndp_mcastreq(ill_t *, const in6_addr_t *, uint32_t, uint32_t,
263     mblk_t *);
264 extern	int	ndp_noresolver(ill_t *, const in6_addr_t *);
265 extern	void	ndp_process(nce_t *, uchar_t *, uint32_t, boolean_t);
266 extern	int	ndp_query(ill_t *, lif_nd_req_t *);
267 extern	int	ndp_report(queue_t *, mblk_t *, caddr_t, cred_t *);
268 extern	int	ndp_resolver(ill_t *, const in6_addr_t *, mblk_t *, zoneid_t);
269 extern	int	ndp_sioc_update(ill_t *, lif_nd_req_t *);
270 extern	boolean_t	ndp_verify_optlen(nd_opt_hdr_t *, int);
271 extern	void	ndp_timer(void *);
272 extern	void	ndp_walk(ill_t *, pfi_t, uchar_t *);
273 extern	void	ndp_walk_impl(ill_t *, pfi_t, uchar_t *, boolean_t);
274 extern	int	ndp_add(ill_t *, uchar_t *, const in6_addr_t *,
275 		    const in6_addr_t *, const in6_addr_t *,
276 		    uint32_t, uint16_t, uint16_t, nce_t **);
277 extern	void	nce_resolv_failed(nce_t *);
278 extern	void	nce_fastpath_list_add(nce_t *);
279 extern	void	nce_fastpath_list_delete(nce_t *);
280 extern	void	nce_fastpath_list_dispatch(ill_t *,
281     boolean_t (*)(nce_t *, void  *), void *);
282 #ifdef NCE_DEBUG
283 extern	void	nce_trace_inactive(nce_t *);
284 extern	void	nce_trace_ref(nce_t *);
285 extern	void	nce_untrace_ref(nce_t *);
286 extern	int	nce_thread_exit(nce_t *, caddr_t);
287 #endif
288 
289 #endif	/* _KERNEL */
290 
291 #ifdef	__cplusplus
292 }
293 #endif
294 
295 #endif	/* _INET_IP_NDP_H */
296