xref: /illumos-gate/usr/src/uts/common/inet/ip_ndp.h (revision bbf21555)
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 /*
27  * Copyright 2019 Joyent, Inc.
28  */
29 
30 #ifndef	_INET_IP_NDP_H
31 #define	_INET_IP_NDP_H
32 
33 #include <sys/mutex.h>
34 #include <sys/stream.h>
35 #include <netinet/in.h>
36 #include <netinet/icmp6.h>
37 #include <inet/ip.h>
38 #include <inet/ip2mac.h>
39 
40 /*
41  * Internal definitions for the kernel implementation of the IPv6
42  * Neighbor Discovery Protocol (NDP) and Address Resolution Protocol (ARP).
43  */
44 
45 #ifdef	__cplusplus
46 extern "C" {
47 #endif
48 
49 #ifdef _KERNEL
50 #define	NCE_TABLE_SIZE	256
51 /*
52  * callbacks set up with ip2mac interface, waiting for result
53  * of neighbor resolution.
54  */
55 typedef struct ncec_cb_s {
56 	list_node_t		ncec_cb_node;	/* next entry in list */
57 	void			*ncec_cb_id;
58 	uint32_t		ncec_cb_flags;
59 	ip2mac_callback_t	*ncec_cb_func;
60 	void			*ncec_cb_arg;
61 } ncec_cb_t;
62 
63 #define	NCE_CB_DISPATCHED	0x00000001
64 
65 /*
66  * Core information tracking Neighbor Reachability is tracked in the
67  * ncec_s/ncec_t. The information contained in the ncec_t does not contain
68  * any link-specific details other than the pointer to the ill_t itself.
69  * The link-specific information is tracked in the nce_t structure.
70  */
71 struct ncec_s {
72 	struct	ncec_s	*ncec_next;	/* Hash chain next pointer */
73 	struct	ncec_s	**ncec_ptpn;	/* Pointer to previous next */
74 	struct	ill_s	*ncec_ill;	/* Associated ill */
75 	uint16_t	ncec_flags;	/* See below */
76 	uint16_t	ncec_state;	/* See reachability states in if.h */
77 	int16_t		ncec_pcnt;	/* Probe counter */
78 	uint16_t	ncec_rcnt;	/* Retransmit counter */
79 	in6_addr_t	ncec_addr;	/* address of the nighbor */
80 	uchar_t		*ncec_lladdr;
81 	mblk_t		*ncec_qd_mp;	/* Head outgoing queued packets */
82 	uint64_t	ncec_last;	/* Time last reachable in msec */
83 	uint32_t	ncec_refcnt;	/* ncec active usage count */
84 	kmutex_t	ncec_lock;	/* See comments on top for what */
85 					/* this field protects */
86 	int		ncec_unsolicit_count; /* Unsolicited Adv count */
87 	timeout_id_t	ncec_timeout_id;
88 	uchar_t		ncec_ipversion;	/* IPv4(ARP)/IPv6(NDP) version */
89 	uint_t		ncec_defense_count;	/* number of NDP conflicts */
90 	clock_t		ncec_last_time_defended; /* defended last (ticks) */
91 	uint64_t	ncec_init_time; /* time when it was set to ND_INITIAL */
92 	boolean_t	ncec_trace_disable;	/* True when alloc fails */
93 	/*
94 	 * interval to keep track of DAD probes.
95 	 */
96 	clock_t		ncec_xmit_interval;
97 	ip_stack_t	*ncec_ipst;	/* Does not have a netstack_hold */
98 	list_t		ncec_cb;	/* callbacks waiting for resolution */
99 	uint_t		ncec_cb_walker_cnt;
100 	uint_t		ncec_nprobes;
101 	uint_t		ncec_lladdr_length;
102 };
103 
104 /*
105  * The nce_t list hangs off the ill_s and tracks information that depends
106  * on the underlying physical link. Thus when the ill goes down,
107  * the nce_t list has to be flushed. This is  done as part of ill_delete()
108  *
109  * When the fastpath ack comes back in ill_fastpath_ack we call
110  * nce_fastpath_update to update the nce_t. We never actually
111  * flush the fastpath list, which is kept as an index into the
112  * ncec_t structures.
113  *
114  * when we ndp_delete, we remove the nce entries pointing
115  * at the dying ncec from the ill_fastpath_list chain.
116  *
117  */
118 struct nce_s	{
119 	list_node_t	nce_node;
120 	ill_t		*nce_ill;
121 	boolean_t	nce_is_condemned;
122 	in6_addr_t	nce_addr;
123 	/*
124 	 * link-layer specific fields below
125 	 */
126 	mblk_t		*nce_dlur_mp;	/* DL_UNITDATA_REQ mp */
127 	mblk_t		*nce_fp_mp;	/* fast path mp */
128 	struct ncec_s	*nce_common;
129 	kmutex_t	nce_lock;
130 	uint32_t	nce_refcnt;
131 	uint_t		nce_ipif_cnt;	/* number of ipifs with the nce_addr */
132 					/* as their local address */
133 };
134 
135 /*
136  * The ndp_g_t structure contains protocol specific information needed
137  * to synchronize and manage neighbor cache entries for IPv4 and IPv6.
138  * There are 2 such structures, ips_ndp4 and ips_ndp6.
139  * ips_ndp6 contains the data structures needed for IPv6 Neighbor Discovery.
140  * ips_ndp4 contains the data structures for IPv4 ARP.
141  *
142  * Locking notes:
143  * ndp_g_lock protects neighbor cache tables access and
144  * insertion/removal of cache entries into/from these tables. The ncec_lock
145  * and nce_lock protect fields in the ncec_t and nce_t structures.
146  * Should there be a need to obtain nce[c]_lock and ndp_g_lock, ndp_g_lock is
147  * acquired first.
148  */
149 typedef	struct ndp_g_s {
150 	kmutex_t	ndp_g_lock;	/* Lock protecting  cache hash table */
151 	ncec_t		*nce_hash_tbl[NCE_TABLE_SIZE];
152 	int		ndp_g_walker; /* # of active thread walking hash list */
153 	boolean_t	ndp_g_walker_cleanup; /* true implies defer deletion. */
154 } ndp_g_t;
155 
156 /* ncec_flags  */
157 #define	NCE_F_MYADDR		0x1	/* ipif exists for the ncec_addr */
158 #define	NCE_F_UNVERIFIED	0x2	/* DAD in progress. */
159 #define	NCE_F_ISROUTER		0x4
160 #define	NCE_F_FAST		0x8
161 
162 /*
163  * NCE_F_NONUD is used to disable IPv6 Neighbor Unreachability Detection or
164  * IPv4 aging and maps to the ATF_PERM flag for arp(8)
165  */
166 #define	NCE_F_NONUD		0x10
167 
168 #define	NCE_F_ANYCAST		0x20
169 #define	NCE_F_CONDEMNED		0x40
170 #define	NCE_F_UNSOL_ADV		0x80
171 #define	NCE_F_BCAST		0x100
172 #define	NCE_F_MCAST		0x200
173 
174 /*
175  * NCE_F_PUBLISH is set for all ARP/ND entries that we announce. This
176  * includes locally configured addresses as well as those that we proxy for.
177  */
178 #define	NCE_F_PUBLISH		0x400
179 
180 /*
181  * NCE_F_AUTHORITY is set for any address that we have authoritatitve
182  * information for. This includes locally configured addresses as well
183  * as statically configured arp entries that are set up using the "permanent"
184  * option described in arp(8). The NCE_F_AUTHORITY asserts that we would
185  * reject any updates for that nce's (host, link-layer-address) information
186  */
187 #define	NCE_F_AUTHORITY		0x800
188 
189 #define	NCE_F_DELAYED		0x1000 /* rescheduled on dad_defend_rate */
190 #define	NCE_F_STATIC		0x2000
191 
192 /* State REACHABLE, STALE, DELAY or PROBE */
193 #define	NCE_ISREACHABLE(ncec)			\
194 	(((((ncec)->ncec_state) >= ND_REACHABLE) &&	\
195 	((ncec)->ncec_state) <= ND_PROBE))
196 
197 #define	NCE_ISCONDEMNED(ncec)	((ncec)->ncec_flags & NCE_F_CONDEMNED)
198 
199 /* NDP flags set in SOL/ADV requests */
200 #define	NDP_UNICAST		0x1
201 #define	NDP_ISROUTER		0x2
202 #define	NDP_SOLICITED		0x4
203 #define	NDP_ORIDE		0x8
204 #define	NDP_PROBE		0x10
205 
206 /* Number of packets queued in NDP for a neighbor */
207 #define	ND_MAX_Q		4
208 
209 /*
210  * Structure for nce_update_hw_changed;
211  */
212 typedef struct {
213 	ipaddr_t hwm_addr;	/* IPv4 address */
214 	uint_t	hwm_hwlen;	/* Length of hardware address (may be 0) */
215 	uchar_t *hwm_hwaddr;	/* Pointer to new hardware address, if any */
216 	int	hwm_flags;
217 } nce_hw_map_t;
218 
219 /* When SAP is greater than zero address appears before SAP */
220 #define	NCE_LL_ADDR_OFFSET(ill)	(((ill)->ill_sap_length) < 0 ? \
221 	(sizeof (dl_unitdata_req_t)) : \
222 	((sizeof (dl_unitdata_req_t)) + (ABS((ill)->ill_sap_length))))
223 
224 #define	NCE_LL_SAP_OFFSET(ill) (((ill)->ill_sap_length) < 0 ? \
225 	((sizeof (dl_unitdata_req_t)) + ((ill)->ill_phys_addr_length)) : \
226 	(sizeof (dl_unitdata_req_t)))
227 
228 #define	NCE_MYADDR(ncec)	(((ncec)->ncec_flags & NCE_F_MYADDR) != 0)
229 
230 /*
231  * NCE_PUBLISH() identifies the addresses that we are publishing. This
232  * includes locally configured address (NCE_MYADDR()) as well as those that
233  * we are proxying.
234  */
235 #define	NCE_PUBLISH(ncec) ((ncec->ncec_flags & NCE_F_PUBLISH) != 0)
236 
237 #ifdef _BIG_ENDIAN
238 #define	NCE_LL_SAP_COPY(ill, mp) \
239 	{ \
240 	size_t abs_sap_len = ABS((ill)->ill_sap_length); \
241 	if (abs_sap_len > 0) { \
242 		ASSERT(abs_sap_len <= sizeof (uint32_t)); \
243 		ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \
244 		    abs_sap_len <= ((mp)->b_wptr)); \
245 		bcopy((uint8_t *)&(ill)->ill_sap + sizeof (ill->ill_sap) - \
246 		    abs_sap_len, \
247 		    ((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \
248 		    abs_sap_len); \
249 	} \
250 	}
251 #else
252 #define	NCE_LL_SAP_COPY(ill, mp) \
253 	{ \
254 	size_t abs_sap_len = ABS((ill)->ill_sap_length); \
255 	if (abs_sap_len > 0) { \
256 		uint32_t abs_sap_len = ABS((ill)->ill_sap_length); \
257 		ASSERT(abs_sap_len <= sizeof (uint32_t)); \
258 		ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \
259 		    abs_sap_len <= ((mp)->b_wptr)); \
260 		bcopy(&((ill)->ill_sap), \
261 		((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \
262 		abs_sap_len); \
263 	} \
264 	}
265 #endif
266 
267 /*
268  * Exclusive-or the 6 bytes that are likely to contain the MAC
269  * address. Assumes table_size does not exceed 256.
270  * Assumes EUI-64 format for good hashing.
271  */
272 #define	NCE_ADDR_HASH_V6(addr, table_size)				\
273 	(((addr).s6_addr8[8] ^ (addr).s6_addr8[9] ^			\
274 	(addr).s6_addr8[10] ^ (addr).s6_addr8[13] ^			\
275 	(addr).s6_addr8[14] ^ (addr).s6_addr8[15]) % (table_size))
276 
277 /* NDP Cache Entry Hash Table */
278 #define	NCE_TABLE_SIZE	256
279 
280 typedef void (*ncec_walk_cb_t)(ncec_t *, void *);
281 
282 extern	void	ip_nce_reclaim(void *);
283 extern	void	ncec_delete(ncec_t *);
284 extern	void	ncec_delete_per_ill(ncec_t *, void *);
285 extern	void	nce_fastpath_update(ill_t *, mblk_t  *);
286 extern	nd_opt_hdr_t *ndp_get_option(nd_opt_hdr_t *, int, int);
287 extern	void	ncec_inactive(ncec_t *);
288 extern	void	ndp_input(mblk_t *, ip_recv_attr_t *);
289 extern	ncec_t	*ncec_lookup_illgrp_v6(ill_t *, const in6_addr_t *);
290 extern	ncec_t	*ncec_lookup_illgrp_v4(ill_t *, const in_addr_t *);
291 extern	nce_t	*nce_lookup_v4(ill_t *, const in_addr_t *);
292 extern	nce_t	*nce_lookup_v6(ill_t *, const in6_addr_t *);
293 extern	void	nce_make_unreachable(ncec_t *);
294 extern	mblk_t	*ndp_mcastreq(ill_t *, const in6_addr_t *, uint32_t, uint32_t,
295     mblk_t *);
296 extern  nce_t	*ndp_nce_init(ill_t *, const in6_addr_t *, int);
297 extern  void	nce_process(ncec_t *, uchar_t *, uint32_t, boolean_t);
298 extern	int	ndp_query(ill_t *, lif_nd_req_t *);
299 extern	int	ndp_sioc_update(ill_t *, lif_nd_req_t *);
300 extern	boolean_t	ndp_verify_optlen(nd_opt_hdr_t *, int);
301 extern	void	nce_timer(void *);
302 extern	void	ncec_walk(ill_t *, ncec_walk_cb_t, void *, ip_stack_t *);
303 extern	void	ncec_walk_common(ndp_g_t *, ill_t *, ncec_walk_cb_t,
304     void *, boolean_t);
305 extern	boolean_t	nce_restart_dad(ncec_t *);
306 extern	void	ndp_resolv_failed(ncec_t *);
307 extern	void	arp_resolv_failed(ncec_t *);
308 extern	void	nce_fastpath_list_delete(ill_t *, ncec_t *, list_t *);
309 extern	void	nce_queue_mp(ncec_t *, mblk_t *, boolean_t);
310 extern	void	nce_update_hw_changed(ncec_t *, void *);
311 extern	int	nce_lookup_then_add_v6(ill_t *, uchar_t *, uint_t,
312     const in6_addr_t *, uint16_t, uint16_t, nce_t **);
313 extern	int	nce_lookup_then_add_v4(ill_t *, uchar_t *, uint_t,
314     const in_addr_t *, uint16_t, uint16_t, nce_t **);
315 extern boolean_t nce_cmp_ll_addr(const ncec_t *, const uchar_t *, uint32_t);
316 extern void	nce_update(ncec_t *, uint16_t, uchar_t *);
317 extern nce_t   *nce_lookup_mapping(ill_t *, const in6_addr_t *);
318 
319 extern void	nce_restart_timer(ncec_t *, uint_t);
320 extern void	ncec_refrele(ncec_t *);
321 extern void	ncec_refhold(ncec_t *);
322 extern void	ncec_refrele_notr(ncec_t *);
323 extern void	ncec_refhold_notr(ncec_t *);
324 extern void	nce_resolv_ok(ncec_t *);
325 extern uint32_t	ndp_solicit(ncec_t *, in6_addr_t, ill_t *);
326 extern boolean_t ip_nce_conflict(mblk_t *, ip_recv_attr_t *, ncec_t *);
327 extern boolean_t ndp_announce(ncec_t *);
328 extern void	ip_nce_lookup_and_update(ipaddr_t *, ipif_t *, ip_stack_t *,
329     uchar_t *, int, int);
330 extern void	nce_refrele(nce_t *);
331 extern void	nce_refhold(nce_t *);
332 extern void	nce_delete(nce_t *);
333 extern void	nce_flush(ill_t *, boolean_t);
334 extern void	nce_walk(ill_t *, pfi_t, void *);
335 extern void	ip_ndp_resolve(struct ncec_s *);
336 extern void	ip_addr_recover(ipsq_t *, queue_t *, mblk_t *, void *);
337 
338 #ifdef DEBUG
339 extern	void	nce_trace_ref(ncec_t *);
340 extern	void	nce_untrace_ref(ncec_t *);
341 #endif
342 
343 #endif	/* _KERNEL */
344 
345 #ifdef	__cplusplus
346 }
347 #endif
348 
349 #endif	/* _INET_IP_NDP_H */
350