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