1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2021 Ng Peng Nam Sean 5 * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 #include "opt_inet.h" 31 #include "opt_inet6.h" 32 #include "opt_route.h" 33 #include <sys/types.h> 34 #include <sys/malloc.h> 35 #include <sys/rmlock.h> 36 #include <sys/socket.h> 37 38 #include <net/if.h> 39 #include <net/route.h> 40 #include <net/route/nhop.h> 41 #include <net/route/route_ctl.h> 42 #include <net/route/route_var.h> 43 #include <netinet6/scope6_var.h> 44 #include <netlink/netlink.h> 45 #include <netlink/netlink_ctl.h> 46 #include <netlink/netlink_route.h> 47 #include <netlink/route/route_var.h> 48 49 #define DEBUG_MOD_NAME nl_route 50 #define DEBUG_MAX_LEVEL LOG_DEBUG3 51 #include <netlink/netlink_debug.h> 52 _DECLARE_DEBUG(LOG_INFO); 53 54 static unsigned char 55 get_rtm_type(const struct nhop_object *nh) 56 { 57 int nh_flags = nh->nh_flags; 58 59 /* Use the fact that nhg runtime flags are only NHF_MULTIPATH */ 60 if (nh_flags & NHF_BLACKHOLE) 61 return (RTN_BLACKHOLE); 62 else if (nh_flags & NHF_REJECT) 63 return (RTN_PROHIBIT); 64 return (RTN_UNICAST); 65 } 66 67 static uint8_t 68 nl_get_rtm_protocol(const struct nhop_object *nh) 69 { 70 #ifdef ROUTE_MPATH 71 if (NH_IS_NHGRP(nh)) { 72 const struct nhgrp_object *nhg = (const struct nhgrp_object *)nh; 73 uint8_t origin = nhgrp_get_origin(nhg); 74 if (origin != RTPROT_UNSPEC) 75 return (origin); 76 nh = nhg->nhops[0]; 77 } 78 #endif 79 uint8_t origin = nhop_get_origin(nh); 80 if (origin != RTPROT_UNSPEC) 81 return (origin); 82 /* TODO: remove guesswork once all kernel users fill in origin */ 83 int rt_flags = nhop_get_rtflags(nh); 84 if (rt_flags & RTF_PROTO1) 85 return (RTPROT_ZEBRA); 86 if (rt_flags & RTF_STATIC) 87 return (RTPROT_STATIC); 88 return (RTPROT_KERNEL); 89 } 90 91 static int 92 get_rtmsg_type_from_rtsock(int cmd) 93 { 94 switch (cmd) { 95 case RTM_ADD: 96 case RTM_CHANGE: 97 case RTM_GET: 98 return NL_RTM_NEWROUTE; 99 case RTM_DELETE: 100 return NL_RTM_DELROUTE; 101 } 102 103 return (0); 104 } 105 106 /* 107 * fibnum heuristics 108 * 109 * if (dump && rtm_table == 0 && !rta_table) RT_ALL_FIBS 110 * msg rtm_table RTA_TABLE result 111 * RTM_GETROUTE/dump 0 - RT_ALL_FIBS 112 * RTM_GETROUTE/dump 1 - 1 113 * RTM_GETROUTE/get 0 - 0 114 * 115 */ 116 117 static struct nhop_object * 118 rc_get_nhop(const struct rib_cmd_info *rc) 119 { 120 return ((rc->rc_cmd == RTM_DELETE) ? rc->rc_nh_old : rc->rc_nh_new); 121 } 122 123 static void 124 dump_rc_nhop_gw(struct nl_writer *nw, const struct nhop_object *nh) 125 { 126 #ifdef INET6 127 int upper_family; 128 #endif 129 130 switch (nhop_get_neigh_family(nh)) { 131 case AF_LINK: 132 /* onlink prefix, skip */ 133 break; 134 case AF_INET: 135 nlattr_add(nw, NL_RTA_GATEWAY, 4, &nh->gw4_sa.sin_addr); 136 break; 137 #ifdef INET6 138 case AF_INET6: 139 upper_family = nhop_get_upper_family(nh); 140 if (upper_family == AF_INET6) { 141 struct in6_addr gw6 = nh->gw6_sa.sin6_addr; 142 in6_clearscope(&gw6); 143 144 nlattr_add(nw, NL_RTA_GATEWAY, 16, &gw6); 145 } else if (upper_family == AF_INET) { 146 /* IPv4 over IPv6 */ 147 struct in6_addr gw6 = nh->gw6_sa.sin6_addr; 148 in6_clearscope(&gw6); 149 150 char buf[20]; 151 struct rtvia *via = (struct rtvia *)&buf[0]; 152 via->rtvia_family = AF_INET6; 153 memcpy(via->rtvia_addr, &gw6, 16); 154 nlattr_add(nw, NL_RTA_VIA, 17, via); 155 } 156 break; 157 #endif 158 } 159 } 160 161 static void 162 dump_rc_nhop_mtu(struct nl_writer *nw, const struct nhop_object *nh) 163 { 164 int nla_len = sizeof(struct nlattr) * 2 + sizeof(uint32_t); 165 struct nlattr *nla = nlmsg_reserve_data(nw, nla_len, struct nlattr); 166 167 if (nla == NULL) 168 return; 169 nla->nla_type = NL_RTA_METRICS; 170 nla->nla_len = nla_len; 171 nla++; 172 nla->nla_type = NL_RTAX_MTU; 173 nla->nla_len = sizeof(struct nlattr) + sizeof(uint32_t); 174 *((uint32_t *)(nla + 1)) = nh->nh_mtu; 175 } 176 177 #ifdef ROUTE_MPATH 178 static void 179 dump_rc_nhg(struct nl_writer *nw, const struct nhgrp_object *nhg, struct rtmsg *rtm) 180 { 181 uint32_t uidx = nhgrp_get_uidx(nhg); 182 uint32_t num_nhops; 183 const struct weightened_nhop *wn = nhgrp_get_nhops(nhg, &num_nhops); 184 uint32_t base_rtflags = nhop_get_rtflags(wn[0].nh); 185 186 if (uidx != 0) 187 nlattr_add_u32(nw, NL_RTA_NH_ID, uidx); 188 nlattr_add_u32(nw, NL_RTA_KNH_ID, nhgrp_get_idx(nhg)); 189 190 nlattr_add_u32(nw, NL_RTA_RTFLAGS, base_rtflags); 191 int off = nlattr_add_nested(nw, NL_RTA_MULTIPATH); 192 if (off == 0) 193 return; 194 195 for (int i = 0; i < num_nhops; i++) { 196 int nh_off = nlattr_save_offset(nw); 197 struct rtnexthop *rtnh = nlmsg_reserve_object(nw, struct rtnexthop); 198 if (rtnh == NULL) 199 return; 200 rtnh->rtnh_flags = 0; 201 rtnh->rtnh_ifindex = if_getindex(wn[i].nh->nh_ifp); 202 rtnh->rtnh_hops = wn[i].weight; 203 dump_rc_nhop_gw(nw, wn[i].nh); 204 uint32_t rtflags = nhop_get_rtflags(wn[i].nh); 205 if (rtflags != base_rtflags) 206 nlattr_add_u32(nw, NL_RTA_RTFLAGS, rtflags); 207 if (rtflags & RTF_FIXEDMTU) 208 dump_rc_nhop_mtu(nw, wn[i].nh); 209 rtnh = nlattr_restore_offset(nw, nh_off, struct rtnexthop); 210 /* 211 * nlattr_add() allocates 4-byte aligned storage, no need to aligh 212 * length here 213 * */ 214 rtnh->rtnh_len = nlattr_save_offset(nw) - nh_off; 215 } 216 nlattr_set_len(nw, off); 217 } 218 #endif 219 220 static void 221 dump_rc_nhop(struct nl_writer *nw, const struct route_nhop_data *rnd, struct rtmsg *rtm) 222 { 223 #ifdef ROUTE_MPATH 224 if (NH_IS_NHGRP(rnd->rnd_nhop)) { 225 dump_rc_nhg(nw, rnd->rnd_nhgrp, rtm); 226 return; 227 } 228 #endif 229 const struct nhop_object *nh = rnd->rnd_nhop; 230 uint32_t rtflags = nhop_get_rtflags(nh); 231 232 /* 233 * IPv4 over IPv6 234 * ('RTA_VIA', {'family': 10, 'addr': 'fe80::20c:29ff:fe67:2dd'}), ('RTA_OIF', 2), 235 * IPv4 w/ gw 236 * ('RTA_GATEWAY', '172.16.107.131'), ('RTA_OIF', 2)], 237 * Direct route: 238 * ('RTA_OIF', 2) 239 */ 240 if (nh->nh_flags & NHF_GATEWAY) 241 dump_rc_nhop_gw(nw, nh); 242 243 uint32_t uidx = nhop_get_uidx(nh); 244 if (uidx != 0) 245 nlattr_add_u32(nw, NL_RTA_NH_ID, uidx); 246 nlattr_add_u32(nw, NL_RTA_KNH_ID, nhop_get_idx(nh)); 247 nlattr_add_u32(nw, NL_RTA_RTFLAGS, rtflags); 248 249 if (rtflags & RTF_FIXEDMTU) 250 dump_rc_nhop_mtu(nw, nh); 251 uint32_t nh_expire = nhop_get_expire(nh); 252 if (nh_expire > 0) 253 nlattr_add_u32(nw, NL_RTA_EXPIRES, nh_expire - time_uptime); 254 255 /* In any case, fill outgoing interface */ 256 nlattr_add_u32(nw, NL_RTA_OIF, if_getindex(nh->nh_ifp)); 257 258 if (rnd->rnd_weight != RT_DEFAULT_WEIGHT) 259 nlattr_add_u32(nw, NL_RTA_WEIGHT, rnd->rnd_weight); 260 } 261 262 /* 263 * Dumps output from a rib command into an rtmsg 264 */ 265 266 static int 267 dump_px(uint32_t fibnum, const struct nlmsghdr *hdr, 268 const struct rtentry *rt, struct route_nhop_data *rnd, 269 struct nl_writer *nw) 270 { 271 struct rtmsg *rtm; 272 int error = 0; 273 274 NET_EPOCH_ASSERT(); 275 276 if (!nlmsg_reply(nw, hdr, sizeof(struct rtmsg))) 277 goto enomem; 278 279 int family = rt_get_family(rt); 280 int rtm_off = nlattr_save_offset(nw); 281 rtm = nlmsg_reserve_object(nw, struct rtmsg); 282 rtm->rtm_family = family; 283 rtm->rtm_dst_len = 0; 284 rtm->rtm_src_len = 0; 285 rtm->rtm_tos = 0; 286 if (fibnum < 255) 287 rtm->rtm_table = (unsigned char)fibnum; 288 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 289 rtm->rtm_protocol = nl_get_rtm_protocol(rnd->rnd_nhop); 290 rtm->rtm_type = get_rtm_type(rnd->rnd_nhop); 291 292 nlattr_add_u32(nw, NL_RTA_TABLE, fibnum); 293 294 int plen = 0; 295 #if defined(INET) || defined(INET6) 296 uint32_t scopeid; 297 #endif 298 switch (family) { 299 #ifdef INET 300 case AF_INET: 301 { 302 struct in_addr addr; 303 rt_get_inet_prefix_plen(rt, &addr, &plen, &scopeid); 304 nlattr_add(nw, NL_RTA_DST, 4, &addr); 305 break; 306 } 307 #endif 308 #ifdef INET6 309 case AF_INET6: 310 { 311 struct in6_addr addr; 312 rt_get_inet6_prefix_plen(rt, &addr, &plen, &scopeid); 313 nlattr_add(nw, NL_RTA_DST, 16, &addr); 314 break; 315 } 316 #endif 317 default: 318 FIB_LOG(LOG_NOTICE, fibnum, family, "unsupported rt family: %d", family); 319 error = EAFNOSUPPORT; 320 goto flush; 321 } 322 323 rtm = nlattr_restore_offset(nw, rtm_off, struct rtmsg); 324 if (plen > 0) 325 rtm->rtm_dst_len = plen; 326 dump_rc_nhop(nw, rnd, rtm); 327 328 if (nlmsg_end(nw)) 329 return (0); 330 enomem: 331 error = ENOMEM; 332 flush: 333 nlmsg_abort(nw); 334 return (error); 335 } 336 337 static int 338 family_to_group(int family) 339 { 340 switch (family) { 341 case AF_INET: 342 return (RTNLGRP_IPV4_ROUTE); 343 case AF_INET6: 344 return (RTNLGRP_IPV6_ROUTE); 345 } 346 return (0); 347 } 348 349 static void 350 report_operation(uint32_t fibnum, struct rib_cmd_info *rc, 351 struct nlpcb *nlp, struct nlmsghdr *hdr) 352 { 353 struct nl_writer nw = {}; 354 uint32_t group_id = family_to_group(rt_get_family(rc->rc_rt)); 355 356 if (nlmsg_get_group_writer(&nw, NLMSG_SMALL, NETLINK_ROUTE, group_id)) { 357 struct route_nhop_data rnd = { 358 .rnd_nhop = rc_get_nhop(rc), 359 .rnd_weight = rc->rc_nh_weight, 360 }; 361 hdr->nlmsg_flags &= ~(NLM_F_REPLACE | NLM_F_CREATE); 362 hdr->nlmsg_flags &= ~(NLM_F_EXCL | NLM_F_APPEND); 363 switch (rc->rc_cmd) { 364 case RTM_ADD: 365 hdr->nlmsg_type = NL_RTM_NEWROUTE; 366 hdr->nlmsg_flags |= NLM_F_CREATE | NLM_F_EXCL; 367 break; 368 case RTM_CHANGE: 369 hdr->nlmsg_type = NL_RTM_NEWROUTE; 370 hdr->nlmsg_flags |= NLM_F_REPLACE; 371 break; 372 case RTM_DELETE: 373 hdr->nlmsg_type = NL_RTM_DELROUTE; 374 break; 375 } 376 dump_px(fibnum, hdr, rc->rc_rt, &rnd, &nw); 377 nlmsg_flush(&nw); 378 } 379 380 rtsock_callback_p->route_f(fibnum, rc); 381 } 382 383 static void 384 set_scope6(struct sockaddr *sa, struct ifnet *ifp) 385 { 386 #ifdef INET6 387 if (sa != NULL && sa->sa_family == AF_INET6 && ifp != NULL) { 388 struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *)sa; 389 390 if (IN6_IS_ADDR_LINKLOCAL(&sa6->sin6_addr)) 391 in6_set_unicast_scopeid(&sa6->sin6_addr, if_getindex(ifp)); 392 } 393 #endif 394 } 395 396 struct rta_mpath_nh { 397 struct sockaddr *gw; 398 struct ifnet *ifp; 399 uint8_t rtnh_flags; 400 uint8_t rtnh_weight; 401 }; 402 403 #define _IN(_field) offsetof(struct rtnexthop, _field) 404 #define _OUT(_field) offsetof(struct rta_mpath_nh, _field) 405 const static struct nlattr_parser nla_p_rtnh[] = { 406 { .type = NL_RTA_GATEWAY, .off = _OUT(gw), .cb = nlattr_get_ip }, 407 { .type = NL_RTA_VIA, .off = _OUT(gw), .cb = nlattr_get_ipvia }, 408 }; 409 const static struct nlfield_parser nlf_p_rtnh[] = { 410 { .off_in = _IN(rtnh_flags), .off_out = _OUT(rtnh_flags), .cb = nlf_get_u8 }, 411 { .off_in = _IN(rtnh_hops), .off_out = _OUT(rtnh_weight), .cb = nlf_get_u8 }, 412 { .off_in = _IN(rtnh_ifindex), .off_out = _OUT(ifp), .cb = nlf_get_ifpz }, 413 }; 414 #undef _IN 415 #undef _OUT 416 417 static bool 418 post_p_rtnh(void *_attrs, struct nl_pstate *npt __unused) 419 { 420 struct rta_mpath_nh *attrs = (struct rta_mpath_nh *)_attrs; 421 422 set_scope6(attrs->gw, attrs->ifp); 423 return (true); 424 } 425 NL_DECLARE_PARSER_EXT(mpath_parser, struct rtnexthop, NULL, nlf_p_rtnh, nla_p_rtnh, post_p_rtnh); 426 427 struct rta_mpath { 428 int num_nhops; 429 struct rta_mpath_nh nhops[0]; 430 }; 431 432 static int 433 nlattr_get_multipath(struct nlattr *nla, struct nl_pstate *npt, const void *arg, void *target) 434 { 435 int data_len = nla->nla_len - sizeof(struct nlattr); 436 struct rtnexthop *rtnh; 437 438 int max_nhops = data_len / sizeof(struct rtnexthop); 439 440 struct rta_mpath *mp = npt_alloc(npt, (max_nhops + 2) * sizeof(struct rta_mpath_nh)); 441 mp->num_nhops = 0; 442 443 for (rtnh = (struct rtnexthop *)(nla + 1); data_len > 0; ) { 444 struct rta_mpath_nh *mpnh = &mp->nhops[mp->num_nhops++]; 445 446 int error = nl_parse_header(rtnh, rtnh->rtnh_len, &mpath_parser, 447 npt, mpnh); 448 if (error != 0) { 449 NLMSG_REPORT_ERR_MSG(npt, "RTA_MULTIPATH: nexhop %d: parse failed", 450 mp->num_nhops - 1); 451 return (error); 452 } 453 454 int len = NL_ITEM_ALIGN(rtnh->rtnh_len); 455 data_len -= len; 456 rtnh = (struct rtnexthop *)((char *)rtnh + len); 457 } 458 if (data_len != 0 || mp->num_nhops == 0) { 459 NLMSG_REPORT_ERR_MSG(npt, "invalid RTA_MULTIPATH attr"); 460 return (EINVAL); 461 } 462 463 *((struct rta_mpath **)target) = mp; 464 return (0); 465 } 466 467 468 struct nl_parsed_route { 469 struct sockaddr *rta_dst; 470 struct sockaddr *rta_gw; 471 struct ifnet *rta_oif; 472 struct rta_mpath *rta_multipath; 473 uint32_t rta_table; 474 uint32_t rta_rtflags; 475 uint32_t rta_nh_id; 476 uint32_t rta_weight; 477 uint32_t rtax_mtu; 478 uint8_t rtm_family; 479 uint8_t rtm_dst_len; 480 uint8_t rtm_protocol; 481 uint8_t rtm_type; 482 uint32_t rtm_flags; 483 }; 484 485 #define _IN(_field) offsetof(struct rtmsg, _field) 486 #define _OUT(_field) offsetof(struct nl_parsed_route, _field) 487 static struct nlattr_parser nla_p_rtmetrics[] = { 488 { .type = NL_RTAX_MTU, .off = _OUT(rtax_mtu), .cb = nlattr_get_uint32 }, 489 }; 490 NL_DECLARE_ATTR_PARSER(metrics_parser, nla_p_rtmetrics); 491 492 static const struct nlattr_parser nla_p_rtmsg[] = { 493 { .type = NL_RTA_DST, .off = _OUT(rta_dst), .cb = nlattr_get_ip }, 494 { .type = NL_RTA_OIF, .off = _OUT(rta_oif), .cb = nlattr_get_ifp }, 495 { .type = NL_RTA_GATEWAY, .off = _OUT(rta_gw), .cb = nlattr_get_ip }, 496 { .type = NL_RTA_METRICS, .arg = &metrics_parser, .cb = nlattr_get_nested }, 497 { .type = NL_RTA_MULTIPATH, .off = _OUT(rta_multipath), .cb = nlattr_get_multipath }, 498 { .type = NL_RTA_WEIGHT, .off = _OUT(rta_weight), .cb = nlattr_get_uint32 }, 499 { .type = NL_RTA_RTFLAGS, .off = _OUT(rta_rtflags), .cb = nlattr_get_uint32 }, 500 { .type = NL_RTA_TABLE, .off = _OUT(rta_table), .cb = nlattr_get_uint32 }, 501 { .type = NL_RTA_VIA, .off = _OUT(rta_gw), .cb = nlattr_get_ipvia }, 502 { .type = NL_RTA_NH_ID, .off = _OUT(rta_nh_id), .cb = nlattr_get_uint32 }, 503 }; 504 505 static const struct nlfield_parser nlf_p_rtmsg[] = { 506 { .off_in = _IN(rtm_family), .off_out = _OUT(rtm_family), .cb = nlf_get_u8 }, 507 { .off_in = _IN(rtm_dst_len), .off_out = _OUT(rtm_dst_len), .cb = nlf_get_u8 }, 508 { .off_in = _IN(rtm_protocol), .off_out = _OUT(rtm_protocol), .cb = nlf_get_u8 }, 509 { .off_in = _IN(rtm_type), .off_out = _OUT(rtm_type), .cb = nlf_get_u8 }, 510 { .off_in = _IN(rtm_flags), .off_out = _OUT(rtm_flags), .cb = nlf_get_u32 }, 511 }; 512 #undef _IN 513 #undef _OUT 514 515 static bool 516 post_p_rtmsg(void *_attrs, struct nl_pstate *npt __unused) 517 { 518 struct nl_parsed_route *attrs = (struct nl_parsed_route *)_attrs; 519 520 set_scope6(attrs->rta_dst, attrs->rta_oif); 521 set_scope6(attrs->rta_gw, attrs->rta_oif); 522 return (true); 523 } 524 NL_DECLARE_PARSER_EXT(rtm_parser, struct rtmsg, NULL, nlf_p_rtmsg, nla_p_rtmsg, post_p_rtmsg); 525 526 struct netlink_walkargs { 527 struct nl_writer *nw; 528 struct route_nhop_data rnd; 529 struct nlmsghdr hdr; 530 struct nlpcb *nlp; 531 uint32_t fibnum; 532 int family; 533 int error; 534 int count; 535 int dumped; 536 int dumped_tables; 537 }; 538 539 static int 540 dump_rtentry(struct rtentry *rt, void *_arg) 541 { 542 struct netlink_walkargs *wa = (struct netlink_walkargs *)_arg; 543 int error; 544 545 wa->count++; 546 if (wa->error != 0) 547 return (0); 548 if (!rt_is_exportable(rt, nlp_get_cred(wa->nlp))) 549 return (0); 550 wa->dumped++; 551 552 rt_get_rnd(rt, &wa->rnd); 553 554 error = dump_px(wa->fibnum, &wa->hdr, rt, &wa->rnd, wa->nw); 555 556 IF_DEBUG_LEVEL(LOG_DEBUG3) { 557 char rtbuf[INET6_ADDRSTRLEN + 5]; 558 FIB_LOG(LOG_DEBUG3, wa->fibnum, wa->family, 559 "Dump %s, error %d", 560 rt_print_buf(rt, rtbuf, sizeof(rtbuf)), error); 561 } 562 wa->error = error; 563 564 return (0); 565 } 566 567 static void 568 dump_rtable_one(struct netlink_walkargs *wa, uint32_t fibnum, int family) 569 { 570 FIB_LOG(LOG_DEBUG2, fibnum, family, "Start dump"); 571 wa->count = 0; 572 wa->dumped = 0; 573 574 rib_walk(fibnum, family, false, dump_rtentry, wa); 575 576 wa->dumped_tables++; 577 578 FIB_LOG(LOG_DEBUG2, fibnum, family, "End dump, iterated %d dumped %d", 579 wa->count, wa->dumped); 580 } 581 582 static int 583 dump_rtable_fib(struct netlink_walkargs *wa, uint32_t fibnum, int family) 584 { 585 wa->fibnum = fibnum; 586 587 if (family == AF_UNSPEC) { 588 for (int i = 0; i < AF_MAX; i++) { 589 if (rt_tables_get_rnh(fibnum, i) != 0) { 590 wa->family = i; 591 dump_rtable_one(wa, fibnum, i); 592 if (wa->error != 0) 593 break; 594 } 595 } 596 } else { 597 if (rt_tables_get_rnh(fibnum, family) != 0) { 598 wa->family = family; 599 dump_rtable_one(wa, fibnum, family); 600 } 601 } 602 603 return (wa->error); 604 } 605 606 static int 607 handle_rtm_getroute(struct nlpcb *nlp, struct nl_parsed_route *attrs, 608 struct nlmsghdr *hdr, struct nl_pstate *npt) 609 { 610 RIB_RLOCK_TRACKER; 611 struct rib_head *rnh; 612 const struct rtentry *rt; 613 struct route_nhop_data rnd; 614 uint32_t fibnum = attrs->rta_table; 615 sa_family_t family = attrs->rtm_family; 616 617 if (attrs->rta_dst == NULL) { 618 NLMSG_REPORT_ERR_MSG(npt, "No RTA_DST supplied"); 619 return (EINVAL); 620 } 621 622 rnh = rt_tables_get_rnh(fibnum, family); 623 if (rnh == NULL) 624 return (EAFNOSUPPORT); 625 626 RIB_RLOCK(rnh); 627 628 struct sockaddr *dst = attrs->rta_dst; 629 630 if (attrs->rtm_flags & RTM_F_PREFIX) 631 rt = rib_lookup_prefix_plen(rnh, dst, attrs->rtm_dst_len, &rnd); 632 else 633 rt = (const struct rtentry *)rnh->rnh_matchaddr(dst, &rnh->head); 634 if (rt == NULL) { 635 RIB_RUNLOCK(rnh); 636 return (ESRCH); 637 } 638 639 rt_get_rnd(rt, &rnd); 640 rnd.rnd_nhop = nhop_select_func(rnd.rnd_nhop, 0); 641 642 RIB_RUNLOCK(rnh); 643 644 if (!rt_is_exportable(rt, nlp_get_cred(nlp))) 645 return (ESRCH); 646 647 IF_DEBUG_LEVEL(LOG_DEBUG2) { 648 char rtbuf[NHOP_PRINT_BUFSIZE] __unused, nhbuf[NHOP_PRINT_BUFSIZE] __unused; 649 FIB_LOG(LOG_DEBUG2, fibnum, family, "getroute completed: got %s for %s", 650 nhop_print_buf_any(rnd.rnd_nhop, nhbuf, sizeof(nhbuf)), 651 rt_print_buf(rt, rtbuf, sizeof(rtbuf))); 652 } 653 654 hdr->nlmsg_type = NL_RTM_NEWROUTE; 655 dump_px(fibnum, hdr, rt, &rnd, npt->nw); 656 657 return (0); 658 } 659 660 static int 661 handle_rtm_dump(struct nlpcb *nlp, uint32_t fibnum, int family, 662 struct nlmsghdr *hdr, struct nl_writer *nw) 663 { 664 struct netlink_walkargs wa = { 665 .nlp = nlp, 666 .nw = nw, 667 .hdr.nlmsg_pid = hdr->nlmsg_pid, 668 .hdr.nlmsg_seq = hdr->nlmsg_seq, 669 .hdr.nlmsg_type = NL_RTM_NEWROUTE, 670 .hdr.nlmsg_flags = hdr->nlmsg_flags | NLM_F_MULTI, 671 }; 672 673 if (fibnum == RT_TABLE_UNSPEC) { 674 for (int i = 0; i < V_rt_numfibs; i++) { 675 dump_rtable_fib(&wa, fibnum, family); 676 if (wa.error != 0) 677 break; 678 } 679 } else 680 dump_rtable_fib(&wa, fibnum, family); 681 682 if (wa.error == 0 && wa.dumped_tables == 0) { 683 FIB_LOG(LOG_DEBUG, fibnum, family, "incorrect fibnum/family"); 684 wa.error = ESRCH; 685 // How do we propagate it? 686 } 687 688 if (!nlmsg_end_dump(wa.nw, wa.error, &wa.hdr)) { 689 NL_LOG(LOG_DEBUG, "Unable to finalize the dump"); 690 return (ENOMEM); 691 } 692 693 return (wa.error); 694 } 695 696 static struct nhop_object * 697 finalize_nhop(struct nhop_object *nh, const struct sockaddr *dst, int *perror) 698 { 699 /* 700 * The following MUST be filled: 701 * nh_ifp, nh_ifa, nh_gw 702 */ 703 if (nh->gw_sa.sa_family == 0) { 704 /* 705 * Empty gateway. Can be direct route with RTA_OIF set. 706 */ 707 if (nh->nh_ifp != NULL) 708 nhop_set_direct_gw(nh, nh->nh_ifp); 709 else { 710 NL_LOG(LOG_DEBUG, "empty gateway and interface, skipping"); 711 *perror = EINVAL; 712 return (NULL); 713 } 714 /* Both nh_ifp and gateway are set */ 715 } else { 716 /* Gateway is set up, we can derive ifp if not set */ 717 if (nh->nh_ifp == NULL) { 718 uint32_t fibnum = nhop_get_fibnum(nh); 719 uint32_t flags = 0; 720 721 if (nh->nh_flags & NHF_GATEWAY) 722 flags = RTF_GATEWAY; 723 else if (nh->nh_flags & NHF_HOST) 724 flags = RTF_HOST; 725 726 struct ifaddr *ifa = ifa_ifwithroute(flags, dst, &nh->gw_sa, fibnum); 727 if (ifa == NULL) { 728 NL_LOG(LOG_DEBUG, "Unable to determine ifp, skipping"); 729 *perror = EINVAL; 730 return (NULL); 731 } 732 nhop_set_transmit_ifp(nh, ifa->ifa_ifp); 733 } 734 } 735 /* Both nh_ifp and gateway are set */ 736 if (nh->nh_ifa == NULL) { 737 const struct sockaddr *gw_sa = &nh->gw_sa; 738 739 if (gw_sa->sa_family != dst->sa_family) { 740 /* 741 * Use dst as the target for determining the default 742 * preferred ifa IF 743 * 1) the gateway is link-level (e.g. direct route) 744 * 2) the gateway family is different (e.g. IPv4 over IPv6). 745 */ 746 gw_sa = dst; 747 } 748 749 struct ifaddr *ifa = ifaof_ifpforaddr(gw_sa, nh->nh_ifp); 750 if (ifa == NULL) { 751 /* Try link-level ifa. */ 752 gw_sa = &nh->gw_sa; 753 ifa = ifaof_ifpforaddr(gw_sa, nh->nh_ifp); 754 if (ifa == NULL) { 755 NL_LOG(LOG_DEBUG, "Unable to determine ifa, skipping"); 756 *perror = EINVAL; 757 return (NULL); 758 } 759 } 760 nhop_set_src(nh, ifa); 761 } 762 763 return (nhop_get_nhop(nh, perror)); 764 } 765 766 static int 767 get_pxflag(const struct nl_parsed_route *attrs) 768 { 769 int pxflag = 0; 770 switch (attrs->rtm_family) { 771 case AF_INET: 772 if (attrs->rtm_dst_len == 32) 773 pxflag = NHF_HOST; 774 else if (attrs->rtm_dst_len == 0) 775 pxflag = NHF_DEFAULT; 776 break; 777 case AF_INET6: 778 if (attrs->rtm_dst_len == 128) 779 pxflag = NHF_HOST; 780 else if (attrs->rtm_dst_len == 0) 781 pxflag = NHF_DEFAULT; 782 break; 783 } 784 785 return (pxflag); 786 } 787 788 static int 789 get_op_flags(int nlm_flags) 790 { 791 int op_flags = 0; 792 793 op_flags |= (nlm_flags & NLM_F_REPLACE) ? RTM_F_REPLACE : 0; 794 op_flags |= (nlm_flags & NLM_F_EXCL) ? RTM_F_EXCL : 0; 795 op_flags |= (nlm_flags & NLM_F_CREATE) ? RTM_F_CREATE : 0; 796 op_flags |= (nlm_flags & NLM_F_APPEND) ? RTM_F_APPEND : 0; 797 798 return (op_flags); 799 } 800 801 #ifdef ROUTE_MPATH 802 static int 803 create_nexthop_one(struct nl_parsed_route *attrs, struct rta_mpath_nh *mpnh, 804 struct nl_pstate *npt, struct nhop_object **pnh) 805 { 806 int error; 807 808 if (mpnh->gw == NULL) 809 return (EINVAL); 810 811 struct nhop_object *nh = nhop_alloc(attrs->rta_table, attrs->rtm_family); 812 if (nh == NULL) 813 return (ENOMEM); 814 815 error = nl_set_nexthop_gw(nh, mpnh->gw, mpnh->ifp, npt); 816 if (error != 0) { 817 nhop_free(nh); 818 return (error); 819 } 820 if (mpnh->ifp != NULL) 821 nhop_set_transmit_ifp(nh, mpnh->ifp); 822 nhop_set_pxtype_flag(nh, get_pxflag(attrs)); 823 nhop_set_rtflags(nh, attrs->rta_rtflags); 824 if (attrs->rtm_protocol > RTPROT_STATIC) 825 nhop_set_origin(nh, attrs->rtm_protocol); 826 827 *pnh = finalize_nhop(nh, attrs->rta_dst, &error); 828 829 return (error); 830 } 831 #endif 832 833 static struct nhop_object * 834 create_nexthop_from_attrs(struct nl_parsed_route *attrs, 835 struct nl_pstate *npt, int *perror) 836 { 837 struct nhop_object *nh = NULL; 838 int error = 0; 839 840 if (attrs->rta_multipath != NULL) { 841 #ifdef ROUTE_MPATH 842 /* Multipath w/o explicit nexthops */ 843 int num_nhops = attrs->rta_multipath->num_nhops; 844 struct weightened_nhop *wn = npt_alloc(npt, sizeof(*wn) * num_nhops); 845 846 for (int i = 0; i < num_nhops; i++) { 847 struct rta_mpath_nh *mpnh = &attrs->rta_multipath->nhops[i]; 848 849 error = create_nexthop_one(attrs, mpnh, npt, &wn[i].nh); 850 if (error != 0) { 851 for (int j = 0; j < i; j++) 852 nhop_free(wn[j].nh); 853 break; 854 } 855 wn[i].weight = mpnh->rtnh_weight > 0 ? mpnh->rtnh_weight : 1; 856 } 857 if (error == 0) { 858 struct rib_head *rh = nhop_get_rh(wn[0].nh); 859 struct nhgrp_object *nhg; 860 861 nhg = nhgrp_alloc(rh->rib_fibnum, rh->rib_family, 862 wn, num_nhops, perror); 863 if (nhg != NULL) { 864 if (attrs->rtm_protocol > RTPROT_STATIC) 865 nhgrp_set_origin(nhg, attrs->rtm_protocol); 866 nhg = nhgrp_get_nhgrp(nhg, perror); 867 } 868 for (int i = 0; i < num_nhops; i++) 869 nhop_free(wn[i].nh); 870 if (nhg != NULL) 871 return ((struct nhop_object *)nhg); 872 error = *perror; 873 } 874 #else 875 error = ENOTSUP; 876 #endif 877 *perror = error; 878 } else { 879 nh = nhop_alloc(attrs->rta_table, attrs->rtm_family); 880 if (nh == NULL) { 881 *perror = ENOMEM; 882 return (NULL); 883 } 884 if (attrs->rta_gw != NULL) { 885 *perror = nl_set_nexthop_gw(nh, attrs->rta_gw, attrs->rta_oif, npt); 886 if (*perror != 0) { 887 nhop_free(nh); 888 return (NULL); 889 } 890 } 891 if (attrs->rta_oif != NULL) 892 nhop_set_transmit_ifp(nh, attrs->rta_oif); 893 if (attrs->rtax_mtu != 0) 894 nhop_set_mtu(nh, attrs->rtax_mtu, true); 895 if (attrs->rta_rtflags & RTF_BROADCAST) 896 nhop_set_broadcast(nh, true); 897 if (attrs->rtm_protocol > RTPROT_STATIC) 898 nhop_set_origin(nh, attrs->rtm_protocol); 899 nhop_set_pxtype_flag(nh, get_pxflag(attrs)); 900 nhop_set_rtflags(nh, attrs->rta_rtflags); 901 902 switch (attrs->rtm_type) { 903 case RTN_UNICAST: 904 break; 905 case RTN_BLACKHOLE: 906 nhop_set_blackhole(nh, RTF_BLACKHOLE); 907 break; 908 case RTN_PROHIBIT: 909 case RTN_UNREACHABLE: 910 nhop_set_blackhole(nh, RTF_REJECT); 911 break; 912 /* TODO: return ENOTSUP for other types if strict option is set */ 913 } 914 915 nh = finalize_nhop(nh, attrs->rta_dst, perror); 916 } 917 918 return (nh); 919 } 920 921 static int 922 rtnl_handle_newroute(struct nlmsghdr *hdr, struct nlpcb *nlp, 923 struct nl_pstate *npt) 924 { 925 struct rib_cmd_info rc = {}; 926 struct nhop_object *nh = NULL; 927 int error; 928 929 struct nl_parsed_route attrs = {}; 930 error = nl_parse_nlmsg(hdr, &rtm_parser, npt, &attrs); 931 if (error != 0) 932 return (error); 933 934 /* Check if we have enough data */ 935 if (attrs.rta_dst == NULL) { 936 NL_LOG(LOG_DEBUG, "missing RTA_DST"); 937 return (EINVAL); 938 } 939 940 if (attrs.rta_table >= V_rt_numfibs) { 941 NLMSG_REPORT_ERR_MSG(npt, "invalid fib"); 942 return (EINVAL); 943 } 944 945 if (attrs.rta_nh_id != 0) { 946 /* Referenced uindex */ 947 int pxflag = get_pxflag(&attrs); 948 nh = nl_find_nhop(attrs.rta_table, attrs.rtm_family, attrs.rta_nh_id, 949 pxflag, &error); 950 if (error != 0) 951 return (error); 952 } else { 953 nh = create_nexthop_from_attrs(&attrs, npt, &error); 954 if (error != 0) { 955 NL_LOG(LOG_DEBUG, "Error creating nexthop"); 956 return (error); 957 } 958 } 959 960 if (!NH_IS_NHGRP(nh) && attrs.rta_weight == 0) 961 attrs.rta_weight = RT_DEFAULT_WEIGHT; 962 struct route_nhop_data rnd = { .rnd_nhop = nh, .rnd_weight = attrs.rta_weight }; 963 int op_flags = get_op_flags(hdr->nlmsg_flags); 964 965 error = rib_add_route_px(attrs.rta_table, attrs.rta_dst, attrs.rtm_dst_len, 966 &rnd, op_flags, &rc); 967 if (error == 0) 968 report_operation(attrs.rta_table, &rc, nlp, hdr); 969 return (error); 970 } 971 972 static int 973 path_match_func(const struct rtentry *rt, const struct nhop_object *nh, void *_data) 974 { 975 struct nl_parsed_route *attrs = (struct nl_parsed_route *)_data; 976 977 if ((attrs->rta_gw != NULL) && !rib_match_gw(rt, nh, attrs->rta_gw)) 978 return (0); 979 980 if ((attrs->rta_oif != NULL) && (attrs->rta_oif != nh->nh_ifp)) 981 return (0); 982 983 return (1); 984 } 985 986 static int 987 rtnl_handle_delroute(struct nlmsghdr *hdr, struct nlpcb *nlp, 988 struct nl_pstate *npt) 989 { 990 struct rib_cmd_info rc; 991 int error; 992 993 struct nl_parsed_route attrs = {}; 994 error = nl_parse_nlmsg(hdr, &rtm_parser, npt, &attrs); 995 if (error != 0) 996 return (error); 997 998 if (attrs.rta_dst == NULL) { 999 NLMSG_REPORT_ERR_MSG(npt, "RTA_DST is not set"); 1000 return (ESRCH); 1001 } 1002 1003 if (attrs.rta_table >= V_rt_numfibs) { 1004 NLMSG_REPORT_ERR_MSG(npt, "invalid fib"); 1005 return (EINVAL); 1006 } 1007 1008 error = rib_del_route_px(attrs.rta_table, attrs.rta_dst, 1009 attrs.rtm_dst_len, path_match_func, &attrs, 0, &rc); 1010 if (error == 0) 1011 report_operation(attrs.rta_table, &rc, nlp, hdr); 1012 return (error); 1013 } 1014 1015 static int 1016 rtnl_handle_getroute(struct nlmsghdr *hdr, struct nlpcb *nlp, struct nl_pstate *npt) 1017 { 1018 int error; 1019 1020 struct nl_parsed_route attrs = {}; 1021 error = nl_parse_nlmsg(hdr, &rtm_parser, npt, &attrs); 1022 if (error != 0) 1023 return (error); 1024 1025 if (attrs.rta_table >= V_rt_numfibs) { 1026 NLMSG_REPORT_ERR_MSG(npt, "invalid fib"); 1027 return (EINVAL); 1028 } 1029 1030 if (hdr->nlmsg_flags & NLM_F_DUMP) 1031 error = handle_rtm_dump(nlp, attrs.rta_table, attrs.rtm_family, hdr, npt->nw); 1032 else 1033 error = handle_rtm_getroute(nlp, &attrs, hdr, npt); 1034 1035 return (error); 1036 } 1037 1038 void 1039 rtnl_handle_route_event(uint32_t fibnum, const struct rib_cmd_info *rc) 1040 { 1041 struct nl_writer nw = {}; 1042 int family, nlm_flags = 0; 1043 1044 family = rt_get_family(rc->rc_rt); 1045 1046 /* XXX: check if there are active listeners first */ 1047 1048 /* TODO: consider passing PID/type/seq */ 1049 switch (rc->rc_cmd) { 1050 case RTM_ADD: 1051 nlm_flags = NLM_F_EXCL | NLM_F_CREATE; 1052 break; 1053 case RTM_CHANGE: 1054 nlm_flags = NLM_F_REPLACE; 1055 break; 1056 case RTM_DELETE: 1057 nlm_flags = 0; 1058 break; 1059 } 1060 IF_DEBUG_LEVEL(LOG_DEBUG2) { 1061 char rtbuf[NHOP_PRINT_BUFSIZE] __unused; 1062 FIB_LOG(LOG_DEBUG2, fibnum, family, 1063 "received event %s for %s / nlm_flags=%X", 1064 rib_print_cmd(rc->rc_cmd), 1065 rt_print_buf(rc->rc_rt, rtbuf, sizeof(rtbuf)), 1066 nlm_flags); 1067 } 1068 1069 struct nlmsghdr hdr = { 1070 .nlmsg_flags = nlm_flags, 1071 .nlmsg_type = get_rtmsg_type_from_rtsock(rc->rc_cmd), 1072 }; 1073 1074 struct route_nhop_data rnd = { 1075 .rnd_nhop = rc_get_nhop(rc), 1076 .rnd_weight = rc->rc_nh_weight, 1077 }; 1078 1079 uint32_t group_id = family_to_group(family); 1080 if (!nlmsg_get_group_writer(&nw, NLMSG_SMALL, NETLINK_ROUTE, group_id)) { 1081 NL_LOG(LOG_DEBUG, "error allocating event buffer"); 1082 return; 1083 } 1084 1085 dump_px(fibnum, &hdr, rc->rc_rt, &rnd, &nw); 1086 nlmsg_flush(&nw); 1087 } 1088 1089 static const struct rtnl_cmd_handler cmd_handlers[] = { 1090 { 1091 .cmd = NL_RTM_GETROUTE, 1092 .name = "RTM_GETROUTE", 1093 .cb = &rtnl_handle_getroute, 1094 .flags = RTNL_F_ALLOW_NONVNET_JAIL, 1095 }, 1096 { 1097 .cmd = NL_RTM_DELROUTE, 1098 .name = "RTM_DELROUTE", 1099 .cb = &rtnl_handle_delroute, 1100 .priv = PRIV_NET_ROUTE, 1101 }, 1102 { 1103 .cmd = NL_RTM_NEWROUTE, 1104 .name = "RTM_NEWROUTE", 1105 .cb = &rtnl_handle_newroute, 1106 .priv = PRIV_NET_ROUTE, 1107 } 1108 }; 1109 1110 static const struct nlhdr_parser *all_parsers[] = {&mpath_parser, &metrics_parser, &rtm_parser}; 1111 1112 void 1113 rtnl_routes_init(void) 1114 { 1115 NL_VERIFY_PARSERS(all_parsers); 1116 rtnl_register_messages(cmd_handlers, NL_ARRAY_LEN(cmd_handlers)); 1117 } 1118