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 2008 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 #pragma ident "%Z%%M% %I% %E% SMI" 30 31 #include <sys/mutex.h> 32 #include <sys/stream.h> 33 #include <netinet/in.h> 34 #include <netinet/icmp6.h> 35 #include <inet/ip.h> 36 37 /* 38 * Internal definitions for the kernel implementation of the IPv6 39 * Neighbor Discovery Protocol (NDP). 40 */ 41 42 #ifdef __cplusplus 43 extern "C" { 44 #endif 45 46 #ifdef _KERNEL 47 #define NCE_TABLE_SIZE 256 48 /* NDP Cache Entry */ 49 typedef struct nce_s { 50 struct nce_s *nce_next; /* Hash chain next pointer */ 51 struct nce_s **nce_ptpn; /* Pointer to previous next */ 52 struct ill_s *nce_ill; /* Associated ill */ 53 uint16_t nce_flags; /* See below */ 54 uint16_t nce_state; /* See reachability states in if.h */ 55 int16_t nce_pcnt; /* Probe counter */ 56 uint16_t nce_rcnt; /* Retransmit counter */ 57 in6_addr_t nce_addr; /* address of the nighbor */ 58 in6_addr_t nce_mask; /* If not all ones, mask allows an */ 59 /* entry to respond to requests for a group of addresses, for */ 60 /* instantance multicast addresses */ 61 in6_addr_t nce_extract_mask; /* For mappings */ 62 uint32_t nce_ll_extract_start; /* For mappings */ 63 #define nce_first_mp_to_free nce_fp_mp 64 mblk_t *nce_fp_mp; /* link layer fast path mp */ 65 mblk_t *nce_res_mp; /* DL_UNITDATA_REQ */ 66 mblk_t *nce_qd_mp; /* Head outgoing queued packets */ 67 #define nce_last_mp_to_free nce_qd_mp 68 mblk_t *nce_timer_mp; /* NDP timer mblk */ 69 mblk_t *nce_mp; /* mblk we are in, last to be freed */ 70 uint64_t nce_last; /* Time last reachable in msec */ 71 uint32_t nce_refcnt; /* nce active usage count */ 72 kmutex_t nce_lock; /* See comments on top for what */ 73 /* this field protects */ 74 int nce_unsolicit_count; /* Unsolicited Adv count */ 75 struct nce_s *nce_fastpath; /* for fastpath list */ 76 timeout_id_t nce_timeout_id; 77 uchar_t nce_ipversion; /* IPv4(ARP)/IPv6(NDP) version */ 78 uint_t nce_defense_count; /* number of NDP conflicts */ 79 uint_t nce_defense_time; /* last time defended (secs) */ 80 uint64_t nce_init_time; /* time when it was set to ND_INITIAL */ 81 boolean_t nce_trace_disable; /* True when alloc fails */ 82 } nce_t; 83 84 /* 85 * The ndp_g_t structure contains protocol specific information needed 86 * to synchronize and manage neighbor cache entries for IPv4 and IPv6. 87 * There are 2 such structures, ips_ndp4 and ips_ndp6. 88 * ips_ndp6 contains the data structures needed for IPv6 Neighbor Discovery. 89 * ips_ndp4 has IPv4 link layer info in its nce_t structures 90 * Note that the nce_t is not currently used as the arp cache itself; 91 * it is used for the following purposes: 92 * - queue packets in nce_qd_mp while waiting for arp resolution to complete 93 * - nce_{res, fp}_mp are used to track DL_UNITDATA request/responses. 94 * - track state of ARP resolution in the nce_state; 95 * 96 * Locking notes: 97 * ndp_g_lock protects neighbor cache tables access and 98 * insertion/removal of cache entries into/from these tables. 99 * nce_lock protects nce_pcnt, nce_rcnt, nce_qd_mp nce_state, 100 * nce_res_mp, nce_refcnt and nce_last. 101 * nce_refcnt is incremented for every ire pointing to this nce and 102 * every time ndp_lookup() finds an nce. 103 * Should there be a need to obtain nce_lock and ndp_g_lock, ndp_g_lock is 104 * acquired first. 105 * To avoid becoming exclusive when deleting NCEs, ndp_walk() routine holds 106 * the ndp_g_lock (i.e global lock) and marks NCEs to be deleted with 107 * NCE_F_CONDEMNED. When all active users of such NCEs are gone the walk 108 * routine passes a list for deletion to nce_ire_delete_list(). 109 * 110 * When the link-layer address of some onlink host changes, ARP will send 111 * an AR_CN_ANNOUNCE message to ip so that stale neighbor-cache 112 * information will not get used. This message is processed in ip_arp_news() 113 * by walking the nce list, and updating as appropriate. The ndp_g_hw_change 114 * flag is set by ip_arp_news() to notify nce_t users that ip_arp_news() is 115 * in progress. 116 */ 117 typedef struct ndp_g_s { 118 kmutex_t ndp_g_lock; /* Lock protecting cache hash table */ 119 nce_t *nce_mask_entries; /* mask not all ones */ 120 nce_t *nce_hash_tbl[NCE_TABLE_SIZE]; 121 int ndp_g_walker; /* # of active thread walking hash list */ 122 boolean_t ndp_g_walker_cleanup; /* true implies defer deletion. */ 123 int ndp_g_hw_change; /* non-zero if nce flush in progress */ 124 } ndp_g_t; 125 126 #define NDP_HW_CHANGE_INCR(ndp) { \ 127 mutex_enter(&(ndp)->ndp_g_lock); \ 128 (ndp)->ndp_g_hw_change++; \ 129 mutex_exit(&(ndp)->ndp_g_lock); \ 130 } 131 132 #define NDP_HW_CHANGE_DECR(ndp) { \ 133 mutex_enter(&(ndp)->ndp_g_lock); \ 134 (ndp)->ndp_g_hw_change--; \ 135 mutex_exit(&(ndp)->ndp_g_lock); \ 136 } 137 138 /* nce_flags */ 139 #define NCE_F_PERMANENT 0x1 140 #define NCE_F_MAPPING 0x2 141 #define NCE_F_ISROUTER 0x4 142 /* unused 0x8 */ 143 #define NCE_F_NONUD 0x10 144 #define NCE_F_ANYCAST 0x20 145 #define NCE_F_CONDEMNED 0x40 146 #define NCE_F_UNSOL_ADV 0x80 147 #define NCE_F_BCAST 0x100 148 149 #define NCE_EXTERNAL_FLAGS_MASK \ 150 (NCE_F_PERMANENT | NCE_F_MAPPING | NCE_F_ISROUTER | NCE_F_NONUD | \ 151 NCE_F_ANYCAST | NCE_F_UNSOL_ADV) 152 153 /* State REACHABLE, STALE, DELAY or PROBE */ 154 #define NCE_ISREACHABLE(nce) \ 155 (((((nce)->nce_state) >= ND_REACHABLE) && \ 156 ((nce)->nce_state) <= ND_PROBE)) 157 158 /* NDP flags set in SOL/ADV requests */ 159 #define NDP_UNICAST 0x1 160 #define NDP_ISROUTER 0x2 161 #define NDP_SOLICITED 0x4 162 #define NDP_ORIDE 0x8 163 #define NDP_PROBE 0x10 164 165 /* Number of packets queued in NDP for a neighbor */ 166 #define ND_MAX_Q 4 167 168 169 #ifdef DEBUG 170 #define NCE_TRACE_REF(nce) nce_trace_ref(nce) 171 #define NCE_UNTRACE_REF(nce) nce_untrace_ref(nce) 172 #else 173 #define NCE_TRACE_REF(nce) 174 #define NCE_UNTRACE_REF(nce) 175 #endif 176 177 #define NCE_REFHOLD(nce) { \ 178 mutex_enter(&(nce)->nce_lock); \ 179 (nce)->nce_refcnt++; \ 180 ASSERT((nce)->nce_refcnt != 0); \ 181 NCE_TRACE_REF(nce); \ 182 mutex_exit(&(nce)->nce_lock); \ 183 } 184 185 #define NCE_REFHOLD_NOTR(nce) { \ 186 mutex_enter(&(nce)->nce_lock); \ 187 (nce)->nce_refcnt++; \ 188 ASSERT((nce)->nce_refcnt != 0); \ 189 mutex_exit(&(nce)->nce_lock); \ 190 } 191 192 #define NCE_REFHOLD_LOCKED(nce) { \ 193 ASSERT(MUTEX_HELD(&(nce)->nce_lock)); \ 194 (nce)->nce_refcnt++; \ 195 NCE_TRACE_REF(nce); \ 196 } 197 198 /* nce_inactive destroys the mutex thus no mutex_exit is needed */ 199 #define NCE_REFRELE(nce) { \ 200 mutex_enter(&(nce)->nce_lock); \ 201 NCE_UNTRACE_REF(nce); \ 202 ASSERT((nce)->nce_refcnt != 0); \ 203 if (--(nce)->nce_refcnt == 0) \ 204 ndp_inactive(nce); \ 205 else { \ 206 mutex_exit(&(nce)->nce_lock);\ 207 } \ 208 } 209 210 #define NCE_REFRELE_NOTR(nce) { \ 211 mutex_enter(&(nce)->nce_lock); \ 212 ASSERT((nce)->nce_refcnt != 0); \ 213 if (--(nce)->nce_refcnt == 0) \ 214 ndp_inactive(nce); \ 215 else { \ 216 mutex_exit(&(nce)->nce_lock);\ 217 } \ 218 } 219 220 #define NDP_RESTART_TIMER(nce, ms) { \ 221 ASSERT(!MUTEX_HELD(&(nce)->nce_lock)); \ 222 if ((nce)->nce_timeout_id != 0) { \ 223 /* Ok to untimeout bad id. we don't hold a lock. */ \ 224 (void) untimeout((nce)->nce_timeout_id); \ 225 } \ 226 mutex_enter(&(nce)->nce_lock); \ 227 /* Don't start the timer if the nce has been deleted */ \ 228 if (!((nce)->nce_flags & NCE_F_CONDEMNED)) \ 229 nce->nce_timeout_id = timeout(ndp_timer, nce, \ 230 MSEC_TO_TICK(ms) == 0 ? 1 : MSEC_TO_TICK(ms)); \ 231 mutex_exit(&(nce)->nce_lock); \ 232 } 233 234 /* Structure for ndp_cache_count() */ 235 typedef struct { 236 int ncc_total; /* Total number of NCEs */ 237 int ncc_host; /* NCE entries without R bit set */ 238 } ncc_cache_count_t; 239 240 /* 241 * Structure of ndp_cache_reclaim(). Each field is a fraction i.e. 1 means 242 * reclaim all, N means reclaim 1/Nth of all entries, 0 means reclaim none. 243 */ 244 typedef struct { 245 int ncr_host; /* Fraction for host entries */ 246 } nce_cache_reclaim_t; 247 248 /* 249 * Structure for nce_delete_hw_changed; specifies an IPv4 address to link-layer 250 * address mapping. Any route that has a cached copy of a mapping for that 251 * IPv4 address that doesn't match the given mapping must be purged. 252 */ 253 typedef struct { 254 ipaddr_t hwm_addr; /* IPv4 address */ 255 uint_t hwm_hwlen; /* Length of hardware address (may be 0) */ 256 uchar_t *hwm_hwaddr; /* Pointer to new hardware address, if any */ 257 } nce_hw_map_t; 258 259 /* When SAP is greater than zero address appears before SAP */ 260 #define NCE_LL_ADDR_OFFSET(ill) (((ill)->ill_sap_length) < 0 ? \ 261 (sizeof (dl_unitdata_req_t)) : \ 262 ((sizeof (dl_unitdata_req_t)) + (ABS((ill)->ill_sap_length)))) 263 264 #define NCE_LL_SAP_OFFSET(ill) (((ill)->ill_sap_length) < 0 ? \ 265 ((sizeof (dl_unitdata_req_t)) + ((ill)->ill_phys_addr_length)) : \ 266 (sizeof (dl_unitdata_req_t))) 267 268 #ifdef _BIG_ENDIAN 269 #define NCE_LL_SAP_COPY(ill, mp) \ 270 { \ 271 size_t abs_sap_len = ABS((ill)->ill_sap_length); \ 272 if (abs_sap_len > 0) { \ 273 ASSERT(abs_sap_len <= sizeof (uint32_t)); \ 274 ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \ 275 abs_sap_len <= ((mp)->b_wptr)); \ 276 bcopy((uint8_t *)&(ill)->ill_sap + sizeof (ill->ill_sap) - \ 277 abs_sap_len, \ 278 ((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \ 279 abs_sap_len); \ 280 } \ 281 } 282 #else 283 #define NCE_LL_SAP_COPY(ill, mp) \ 284 { \ 285 size_t abs_sap_len = ABS((ill)->ill_sap_length); \ 286 if (abs_sap_len > 0) { \ 287 uint32_t abs_sap_len = ABS((ill)->ill_sap_length); \ 288 ASSERT(abs_sap_len <= sizeof (uint32_t)); \ 289 ASSERT((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill) + \ 290 abs_sap_len <= ((mp)->b_wptr)); \ 291 bcopy(&((ill)->ill_sap), \ 292 ((mp)->b_rptr + NCE_LL_SAP_OFFSET(ill)), \ 293 abs_sap_len); \ 294 } \ 295 } 296 #endif 297 298 /* 299 * Exclusive-or the 6 bytes that are likely to contain the MAC 300 * address. Assumes table_size does not exceed 256. 301 * Assumes EUI-64 format for good hashing. 302 */ 303 #define NCE_ADDR_HASH_V6(addr, table_size) \ 304 (((addr).s6_addr8[8] ^ (addr).s6_addr8[9] ^ \ 305 (addr).s6_addr8[10] ^ (addr).s6_addr8[13] ^ \ 306 (addr).s6_addr8[14] ^ (addr).s6_addr8[15]) % (table_size)) 307 308 /* NDP Cache Entry Hash Table */ 309 #define NCE_TABLE_SIZE 256 310 311 extern void ndp_cache_count(nce_t *, char *); 312 extern void ndp_cache_reclaim(nce_t *, char *); 313 extern void ndp_delete(nce_t *); 314 extern void ndp_delete_per_ill(nce_t *, uchar_t *); 315 extern void ndp_fastpath_flush(nce_t *, char *); 316 extern boolean_t ndp_fastpath_update(nce_t *, void *); 317 extern nd_opt_hdr_t *ndp_get_option(nd_opt_hdr_t *, int, int); 318 extern void ndp_inactive(nce_t *); 319 extern void ndp_input(ill_t *, mblk_t *, mblk_t *); 320 extern boolean_t ndp_lookup_ipaddr(in_addr_t, netstack_t *); 321 extern nce_t *ndp_lookup_v6(ill_t *, const in6_addr_t *, boolean_t); 322 extern nce_t *ndp_lookup_v4(ill_t *, const in_addr_t *, boolean_t); 323 extern int ndp_mcastreq(ill_t *, const in6_addr_t *, uint32_t, uint32_t, 324 mblk_t *); 325 extern int ndp_noresolver(ill_t *, const in6_addr_t *); 326 extern void ndp_process(nce_t *, uchar_t *, uint32_t, boolean_t); 327 extern int ndp_query(ill_t *, lif_nd_req_t *); 328 extern int ndp_resolver(ill_t *, const in6_addr_t *, mblk_t *, zoneid_t); 329 extern int ndp_sioc_update(ill_t *, lif_nd_req_t *); 330 extern boolean_t ndp_verify_optlen(nd_opt_hdr_t *, int); 331 extern void ndp_timer(void *); 332 extern void ndp_walk(ill_t *, pfi_t, void *, ip_stack_t *); 333 extern void ndp_walk_common(ndp_g_t *, ill_t *, pfi_t, 334 void *, boolean_t); 335 extern boolean_t ndp_restart_dad(nce_t *); 336 extern void ndp_do_recovery(ipif_t *); 337 extern void nce_resolv_failed(nce_t *); 338 extern void arp_resolv_failed(nce_t *); 339 extern void nce_fastpath_list_add(nce_t *); 340 extern void nce_fastpath_list_delete(nce_t *); 341 extern void nce_fastpath_list_dispatch(ill_t *, 342 boolean_t (*)(nce_t *, void *), void *); 343 extern void nce_queue_mp_common(nce_t *, mblk_t *, boolean_t); 344 extern void ndp_flush_qd_mp(nce_t *); 345 extern void nce_delete_hw_changed(nce_t *, void *); 346 extern void nce_fastpath(nce_t *); 347 extern int ndp_add_v6(ill_t *, uchar_t *, const in6_addr_t *, 348 const in6_addr_t *, const in6_addr_t *, uint32_t, uint16_t, uint16_t, 349 nce_t **); 350 extern int ndp_lookup_then_add_v6(ill_t *, uchar_t *, 351 const in6_addr_t *, const in6_addr_t *, const in6_addr_t *, uint32_t, 352 uint16_t, uint16_t, nce_t **); 353 extern int ndp_lookup_then_add_v4(ill_t *, 354 const in_addr_t *, uint16_t, nce_t **, nce_t *); 355 356 #ifdef DEBUG 357 extern void nce_trace_ref(nce_t *); 358 extern void nce_untrace_ref(nce_t *); 359 #endif 360 361 #endif /* _KERNEL */ 362 363 #ifdef __cplusplus 364 } 365 #endif 366 367 #endif /* _INET_IP_NDP_H */ 368