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