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 __FBSDID("$FreeBSD$"); 32 33 #include "opt_inet.h" 34 #include "opt_inet6.h" 35 #include "opt_route.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/lock.h> 40 #include <sys/rmlock.h> 41 #include <sys/malloc.h> 42 #include <sys/mbuf.h> 43 #include <sys/socket.h> 44 #include <sys/sysctl.h> 45 #include <sys/kernel.h> 46 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <net/if_dl.h> 50 #include <net/if_private.h> 51 #include <net/route.h> 52 #include <net/route/route_ctl.h> 53 #include <net/route/route_var.h> 54 #include <net/route/fib_algo.h> 55 #include <net/route/nhop.h> 56 #include <net/toeplitz.h> 57 #include <net/vnet.h> 58 59 #include <netinet/in.h> 60 #include <netinet/in_var.h> 61 #include <netinet/ip_mroute.h> 62 #include <netinet/ip6.h> 63 #include <netinet6/in6_fib.h> 64 #include <netinet6/in6_var.h> 65 #include <netinet6/nd6.h> 66 #include <netinet6/scope6_var.h> 67 68 #include <net/if_types.h> 69 70 #ifdef INET6 71 72 CHK_STRUCT_ROUTE_COMPAT(struct route_in6, ro_dst); 73 74 #ifdef FIB_ALGO 75 VNET_DEFINE(struct fib_dp *, inet6_dp); 76 #endif 77 78 #ifdef ROUTE_MPATH 79 struct _hash_5tuple_ipv6 { 80 struct in6_addr src; 81 struct in6_addr dst; 82 unsigned short src_port; 83 unsigned short dst_port; 84 char proto; 85 char spare[3]; 86 }; 87 _Static_assert(sizeof(struct _hash_5tuple_ipv6) == 40, 88 "_hash_5tuple_ipv6 size is wrong"); 89 90 uint32_t 91 fib6_calc_software_hash(const struct in6_addr *src, const struct in6_addr *dst, 92 unsigned short src_port, unsigned short dst_port, char proto, 93 uint32_t *phashtype) 94 { 95 struct _hash_5tuple_ipv6 data; 96 97 data.src = *src; 98 data.dst = *dst; 99 data.src_port = src_port; 100 data.dst_port = dst_port; 101 data.proto = proto; 102 data.spare[0] = data.spare[1] = data.spare[2] = 0; 103 104 *phashtype = M_HASHTYPE_OPAQUE_HASH; 105 106 return (toeplitz_hash(MPATH_ENTROPY_KEY_LEN, mpath_entropy_key, 107 sizeof(data), (uint8_t *)&data)); 108 } 109 #endif 110 111 /* 112 * Looks up path in fib @fibnum specified by @dst. 113 * Assumes scope is deembedded and provided in @scopeid. 114 * 115 * Returns path nexthop on success. Nexthop is safe to use 116 * within the current network epoch. If longer lifetime is required, 117 * one needs to pass NHR_REF as a flag. This will return referenced 118 * nexthop. 119 */ 120 #ifdef FIB_ALGO 121 struct nhop_object * 122 fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6, 123 uint32_t scopeid, uint32_t flags, uint32_t flowid) 124 { 125 struct nhop_object *nh; 126 struct fib_dp *dp = &V_inet6_dp[fibnum]; 127 struct flm_lookup_key key = {.addr6 = dst6 }; 128 129 nh = dp->f(dp->arg, key, scopeid); 130 if (nh != NULL) { 131 nh = nhop_select(nh, flowid); 132 /* Ensure route & ifp is UP */ 133 if (RT_LINK_IS_UP(nh->nh_ifp)) { 134 if (flags & NHR_REF) 135 nhop_ref_object(nh); 136 return (nh); 137 } 138 } 139 RTSTAT_INC(rts_unreach); 140 return (NULL); 141 } 142 #else 143 struct nhop_object * 144 fib6_lookup(uint32_t fibnum, const struct in6_addr *dst6, 145 uint32_t scopeid, uint32_t flags, uint32_t flowid) 146 { 147 RIB_RLOCK_TRACKER; 148 struct rib_head *rh; 149 struct radix_node *rn; 150 struct nhop_object *nh; 151 152 KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum")); 153 rh = rt_tables_get_rnh(fibnum, AF_INET6); 154 if (rh == NULL) 155 return (NULL); 156 157 struct sockaddr_in6 sin6 = { 158 .sin6_len = sizeof(struct sockaddr_in6), 159 .sin6_addr = *dst6, 160 }; 161 162 /* Assume scopeid is valid and embed it directly */ 163 if (IN6_IS_SCOPE_LINKLOCAL(dst6)) 164 sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff); 165 166 RIB_RLOCK(rh); 167 rn = rh->rnh_matchaddr((void *)&sin6, &rh->head); 168 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 169 nh = nhop_select((RNTORT(rn))->rt_nhop, flowid); 170 /* Ensure route & ifp is UP */ 171 if (RT_LINK_IS_UP(nh->nh_ifp)) { 172 if (flags & NHR_REF) 173 nhop_ref_object(nh); 174 RIB_RUNLOCK(rh); 175 return (nh); 176 } 177 } 178 RIB_RUNLOCK(rh); 179 180 RTSTAT_INC(rts_unreach); 181 return (NULL); 182 } 183 #endif 184 185 inline static int 186 check_urpf_nhop(const struct nhop_object *nh, uint32_t flags, 187 const struct ifnet *src_if) 188 { 189 190 if (src_if != NULL && nh->nh_aifp == src_if) { 191 return (1); 192 } 193 if (src_if == NULL) { 194 if ((flags & NHR_NODEFAULT) == 0) 195 return (1); 196 else if ((nh->nh_flags & NHF_DEFAULT) == 0) 197 return (1); 198 } 199 200 return (0); 201 } 202 203 static int 204 check_urpf(struct nhop_object *nh, uint32_t flags, 205 const struct ifnet *src_if) 206 { 207 #ifdef ROUTE_MPATH 208 if (NH_IS_NHGRP(nh)) { 209 const struct weightened_nhop *wn; 210 uint32_t num_nhops; 211 wn = nhgrp_get_nhops((struct nhgrp_object *)nh, &num_nhops); 212 for (int i = 0; i < num_nhops; i++) { 213 if (check_urpf_nhop(wn[i].nh, flags, src_if) != 0) 214 return (1); 215 } 216 return (0); 217 } else 218 #endif 219 return (check_urpf_nhop(nh, flags, src_if)); 220 } 221 222 #ifndef FIB_ALGO 223 static struct nhop_object * 224 lookup_nhop(uint32_t fibnum, const struct in6_addr *dst6, 225 uint32_t scopeid) 226 { 227 RIB_RLOCK_TRACKER; 228 struct rib_head *rh; 229 struct radix_node *rn; 230 struct nhop_object *nh; 231 232 KASSERT((fibnum < rt_numfibs), ("fib6_check_urpf: bad fibnum")); 233 rh = rt_tables_get_rnh(fibnum, AF_INET6); 234 if (rh == NULL) 235 return (NULL); 236 237 /* Prepare lookup key */ 238 struct sockaddr_in6 sin6 = { 239 .sin6_len = sizeof(struct sockaddr_in6), 240 .sin6_addr = *dst6, 241 }; 242 243 /* Assume scopeid is valid and embed it directly */ 244 if (IN6_IS_SCOPE_LINKLOCAL(dst6)) 245 sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff); 246 247 nh = NULL; 248 RIB_RLOCK(rh); 249 rn = rh->rnh_matchaddr((void *)&sin6, &rh->head); 250 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) 251 nh = RNTORT(rn)->rt_nhop; 252 RIB_RUNLOCK(rh); 253 254 return (nh); 255 } 256 #endif 257 258 /* 259 * Performs reverse path forwarding lookup. 260 * If @src_if is non-zero, verifies that at least 1 path goes via 261 * this interface. 262 * If @src_if is zero, verifies that route exist. 263 * if @flags contains NHR_NOTDEFAULT, do not consider default route. 264 * 265 * Returns 1 if route matching conditions is found, 0 otherwise. 266 */ 267 int 268 fib6_check_urpf(uint32_t fibnum, const struct in6_addr *dst6, 269 uint32_t scopeid, uint32_t flags, const struct ifnet *src_if) 270 { 271 struct nhop_object *nh; 272 #ifdef FIB_ALGO 273 struct fib_dp *dp = &V_inet6_dp[fibnum]; 274 struct flm_lookup_key key = {.addr6 = dst6 }; 275 276 nh = dp->f(dp->arg, key, scopeid); 277 #else 278 nh = lookup_nhop(fibnum, dst6, scopeid); 279 #endif 280 if (nh != NULL) 281 return (check_urpf(nh, flags, src_if)); 282 return (0); 283 } 284 285 /* 286 * Function returning prefix match data along with the nexthop data. 287 * Intended to be used by the control plane code. 288 * Supported flags: 289 * NHR_UNLOCKED: do not lock radix during lookup. 290 * Returns pointer to rtentry and raw nexthop in @rnd. Both rtentry 291 * and nexthop are safe to use within current epoch. Note: 292 * Note: rnd_nhop can actually be the nexthop group. 293 */ 294 struct rtentry * 295 fib6_lookup_rt(uint32_t fibnum, const struct in6_addr *dst6, 296 uint32_t scopeid, uint32_t flags, struct route_nhop_data *rnd) 297 { 298 RIB_RLOCK_TRACKER; 299 struct rib_head *rh; 300 struct radix_node *rn; 301 struct rtentry *rt; 302 303 KASSERT((fibnum < rt_numfibs), ("fib6_lookup: bad fibnum")); 304 rh = rt_tables_get_rnh(fibnum, AF_INET6); 305 if (rh == NULL) 306 return (NULL); 307 308 struct sockaddr_in6 sin6 = { 309 .sin6_len = sizeof(struct sockaddr_in6), 310 .sin6_addr = *dst6, 311 }; 312 313 /* Assume scopeid is valid and embed it directly */ 314 if (IN6_IS_SCOPE_LINKLOCAL(dst6)) 315 sin6.sin6_addr.s6_addr16[1] = htons(scopeid & 0xffff); 316 317 rt = NULL; 318 if (!(flags & NHR_UNLOCKED)) 319 RIB_RLOCK(rh); 320 rn = rh->rnh_matchaddr((void *)&sin6, &rh->head); 321 if (rn != NULL && ((rn->rn_flags & RNF_ROOT) == 0)) { 322 rt = (struct rtentry *)rn; 323 rnd->rnd_nhop = rt->rt_nhop; 324 rnd->rnd_weight = rt->rt_weight; 325 } 326 if (!(flags & NHR_UNLOCKED)) 327 RIB_RUNLOCK(rh); 328 329 return (rt); 330 } 331 332 struct nhop_object * 333 fib6_lookup_debugnet(uint32_t fibnum, const struct in6_addr *dst6, 334 uint32_t scopeid, uint32_t flags) 335 { 336 struct rtentry *rt; 337 struct route_nhop_data rnd; 338 339 rt = fib6_lookup_rt(fibnum, dst6, scopeid, NHR_UNLOCKED, &rnd); 340 if (rt != NULL) { 341 struct nhop_object *nh = nhop_select(rnd.rnd_nhop, 0); 342 /* Ensure route & ifp is UP */ 343 if (RT_LINK_IS_UP(nh->nh_ifp)) 344 return (nh); 345 } 346 347 return (NULL); 348 } 349 350 #endif 351