1 /*- 2 * Copyright (c) 2015 3 * Alexander V. Chernikov <melifaro@FreeBSD.org> 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 #include "opt_inet.h" 32 #include "opt_inet6.h" 33 #include "opt_route.h" 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/lock.h> 38 #include <sys/rmlock.h> 39 #include <sys/malloc.h> 40 #include <sys/mbuf.h> 41 #include <sys/socket.h> 42 #include <sys/sysctl.h> 43 #include <sys/kernel.h> 44 45 #include <net/if.h> 46 #include <net/if_var.h> 47 #include <net/if_dl.h> 48 #include <net/if_private.h> 49 #include <net/route.h> 50 #include <net/route/route_ctl.h> 51 #include <net/route/route_var.h> 52 #include <net/route/fib_algo.h> 53 #include <net/route/nhop.h> 54 #include <net/toeplitz.h> 55 #include <net/vnet.h> 56 57 #include <netinet/in.h> 58 #include <netinet/in_var.h> 59 #include <netinet/ip_mroute.h> 60 #include <netinet/ip6.h> 61 #include <netinet6/in6_fib.h> 62 #include <netinet6/in6_var.h> 63 #include <netinet6/nd6.h> 64 #include <netinet6/scope6_var.h> 65 66 #include <net/if_types.h> 67 68 #ifdef INET6 69 70 CHK_STRUCT_ROUTE_COMPAT(struct route_in6, ro_dst); 71 72 #ifdef FIB_ALGO 73 VNET_DEFINE(struct fib_dp *, inet6_dp); 74 #endif 75 76 #ifdef ROUTE_MPATH 77 struct _hash_5tuple_ipv6 { 78 struct in6_addr src; 79 struct in6_addr dst; 80 unsigned short src_port; 81 unsigned short dst_port; 82 char proto; 83 char spare[3]; 84 }; 85 _Static_assert(sizeof(struct _hash_5tuple_ipv6) == 40, 86 "_hash_5tuple_ipv6 size is wrong"); 87 88 uint32_t 89 fib6_calc_software_hash(const struct in6_addr *src, const struct in6_addr *dst, 90 unsigned short src_port, unsigned short dst_port, char proto, 91 uint32_t *phashtype) 92 { 93 struct _hash_5tuple_ipv6 data; 94 95 data.src = *src; 96 data.dst = *dst; 97 data.src_port = src_port; 98 data.dst_port = dst_port; 99 data.proto = proto; 100 data.spare[0] = data.spare[1] = data.spare[2] = 0; 101 102 *phashtype = M_HASHTYPE_OPAQUE_HASH; 103 104 return (toeplitz_hash(MPATH_ENTROPY_KEY_LEN, mpath_entropy_key, 105 sizeof(data), (uint8_t *)&data)); 106 } 107 #endif 108 109 /* 110 * Looks up path in fib @fibnum specified by @dst. 111 * Assumes scope is deembedded and provided in @scopeid. 112 * 113 * Returns path nexthop on success. Nexthop is safe to use 114 * within the current network epoch. If longer lifetime is required, 115 * one needs to pass NHR_REF as a flag. This will return referenced 116 * nexthop. 117 */ 118 #ifdef FIB_ALGO 119 struct nhop_object * 120 fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6, 121 uint32_t scopeid, uint32_t flags, uint32_t flowid) 122 { 123 struct nhop_object *nh; 124 struct fib_dp *dp = &V_inet6_dp[fibnum]; 125 struct flm_lookup_key key = {.addr6 = dst6 }; 126 127 nh = dp->f(dp->arg, key, scopeid); 128 if (nh != NULL) { 129 nh = nhop_select(nh, flowid); 130 /* Ensure route & ifp is UP */ 131 if (RT_LINK_IS_UP(nh->nh_ifp)) { 132 if (flags & NHR_REF) 133 nhop_ref_object(nh); 134 return (nh); 135 } 136 } 137 RTSTAT_INC(rts_unreach); 138 return (NULL); 139 } 140 #else 141 struct nhop_object * 142 fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6, 143 uint32_t scopeid, uint32_t flags, uint32_t flowid) 144 { 145 RIB_RLOCK_TRACKER; 146 struct rib_head *rh; 147 struct radix_node *rn; 148 struct nhop_object *nh; 149 150 KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum")); 151 rh = rt_tables_get_rnh(fibnum, AF_INET6); 152 if (rh == NULL) 153 return (NULL); 154 155 struct sockaddr_in6 sin6 = { 156 .sin6_len = sizeof(struct sockaddr_in6), 157 .sin6_addr = *dst6, 158 }; 159 160 /* Assume scopeid is valid and embed it directly */ 161 if (IN6_IS_SCOPE_LINKLOCAL(dst6)) 162 sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff); 163 164 RIB_RLOCK(rh); 165 rn = rh->rnh_matchaddr((void *)&sin6, &rh->head); 166 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 167 nh = nhop_select((RNTORT(rn))->rt_nhop, flowid); 168 /* Ensure route & ifp is UP */ 169 if (RT_LINK_IS_UP(nh->nh_ifp)) { 170 if (flags & NHR_REF) 171 nhop_ref_object(nh); 172 RIB_RUNLOCK(rh); 173 return (nh); 174 } 175 } 176 RIB_RUNLOCK(rh); 177 178 RTSTAT_INC(rts_unreach); 179 return (NULL); 180 } 181 #endif 182 183 inline static int 184 check_urpf_nhop(const struct nhop_object *nh, uint32_t flags, 185 const struct ifnet *src_if) 186 { 187 188 if (src_if != NULL && nh->nh_aifp == src_if) { 189 return (1); 190 } 191 if (src_if == NULL) { 192 if ((flags & NHR_NODEFAULT) == 0) 193 return (1); 194 else if ((nh->nh_flags & NHF_DEFAULT) == 0) 195 return (1); 196 } 197 198 return (0); 199 } 200 201 static int 202 check_urpf(struct nhop_object *nh, uint32_t flags, 203 const struct ifnet *src_if) 204 { 205 #ifdef ROUTE_MPATH 206 if (NH_IS_NHGRP(nh)) { 207 const struct weightened_nhop *wn; 208 uint32_t num_nhops; 209 wn = nhgrp_get_nhops((struct nhgrp_object *)nh, &num_nhops); 210 for (int i = 0; i < num_nhops; i++) { 211 if (check_urpf_nhop(wn[i].nh, flags, src_if) != 0) 212 return (1); 213 } 214 return (0); 215 } else 216 #endif 217 return (check_urpf_nhop(nh, flags, src_if)); 218 } 219 220 #ifndef FIB_ALGO 221 static struct nhop_object * 222 lookup_nhop(uint32_t fibnum, const struct in6_addr *dst6, 223 uint32_t scopeid) 224 { 225 RIB_RLOCK_TRACKER; 226 struct rib_head *rh; 227 struct radix_node *rn; 228 struct nhop_object *nh; 229 230 KASSERT((fibnum < rt_numfibs), ("fib6_check_urpf: bad fibnum")); 231 rh = rt_tables_get_rnh(fibnum, AF_INET6); 232 if (rh == NULL) 233 return (NULL); 234 235 /* Prepare lookup key */ 236 struct sockaddr_in6 sin6 = { 237 .sin6_len = sizeof(struct sockaddr_in6), 238 .sin6_addr = *dst6, 239 }; 240 241 /* Assume scopeid is valid and embed it directly */ 242 if (IN6_IS_SCOPE_LINKLOCAL(dst6)) 243 sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff); 244 245 nh = NULL; 246 RIB_RLOCK(rh); 247 rn = rh->rnh_matchaddr((void *)&sin6, &rh->head); 248 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) 249 nh = RNTORT(rn)->rt_nhop; 250 RIB_RUNLOCK(rh); 251 252 return (nh); 253 } 254 #endif 255 256 /* 257 * Performs reverse path forwarding lookup. 258 * If @src_if is non-zero, verifies that at least 1 path goes via 259 * this interface. 260 * If @src_if is zero, verifies that route exist. 261 * if @flags contains NHR_NOTDEFAULT, do not consider default route. 262 * 263 * Returns 1 if route matching conditions is found, 0 otherwise. 264 */ 265 int 266 fib6_check_urpf(uint32_t fibnum, const struct in6_addr *dst6, 267 uint32_t scopeid, uint32_t flags, const struct ifnet *src_if) 268 { 269 struct nhop_object *nh; 270 #ifdef FIB_ALGO 271 struct fib_dp *dp = &V_inet6_dp[fibnum]; 272 struct flm_lookup_key key = {.addr6 = dst6 }; 273 274 nh = dp->f(dp->arg, key, scopeid); 275 #else 276 nh = lookup_nhop(fibnum, dst6, scopeid); 277 #endif 278 if (nh != NULL) 279 return (check_urpf(nh, flags, src_if)); 280 return (0); 281 } 282 283 /* 284 * Function returning prefix match data along with the nexthop data. 285 * Intended to be used by the control plane code. 286 * Supported flags: 287 * NHR_UNLOCKED: do not lock radix during lookup. 288 * Returns pointer to rtentry and raw nexthop in @rnd. Both rtentry 289 * and nexthop are safe to use within current epoch. Note: 290 * Note: rnd_nhop can actually be the nexthop group. 291 */ 292 struct rtentry * 293 fib6_lookup_rt(uint32_t fibnum, const struct in6_addr *dst6, 294 uint32_t scopeid, uint32_t flags, struct route_nhop_data *rnd) 295 { 296 RIB_RLOCK_TRACKER; 297 struct rib_head *rh; 298 struct radix_node *rn; 299 struct rtentry *rt; 300 301 KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum")); 302 rh = rt_tables_get_rnh(fibnum, AF_INET6); 303 if (rh == NULL) 304 return (NULL); 305 306 struct sockaddr_in6 sin6 = { 307 .sin6_len = sizeof(struct sockaddr_in6), 308 .sin6_addr = *dst6, 309 }; 310 311 /* Assume scopeid is valid and embed it directly */ 312 if (IN6_IS_SCOPE_LINKLOCAL(dst6)) 313 sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff); 314 315 rt = NULL; 316 if (!(flags & NHR_UNLOCKED)) 317 RIB_RLOCK(rh); 318 rn = rh->rnh_matchaddr((void *)&sin6, &rh->head); 319 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 320 rt = (struct rtentry *)rn; 321 rnd->rnd_nhop = rt->rt_nhop; 322 rnd->rnd_weight = rt->rt_weight; 323 } 324 if (!(flags & NHR_UNLOCKED)) 325 RIB_RUNLOCK(rh); 326 327 return (rt); 328 } 329 330 struct nhop_object * 331 fib6_lookup_debugnet(uint32_t fibnum, const struct in6_addr *dst6, 332 uint32_t scopeid, uint32_t flags) 333 { 334 struct rtentry *rt; 335 struct route_nhop_data rnd; 336 337 rt = fib6_lookup_rt(fibnum, dst6, scopeid, NHR_UNLOCKED, &rnd); 338 if (rt != NULL) { 339 struct nhop_object *nh = nhop_select(rnd.rnd_nhop, 0); 340 /* Ensure route & ifp is UP */ 341 if (RT_LINK_IS_UP(nh->nh_ifp)) 342 return (nh); 343 } 344 345 return (NULL); 346 } 347 348 #endif 349