bgpd.c revision 1.77
1/* $OpenBSD: bgpd.c,v 1.77 2004/02/09 01:38:55 henning Exp $ */ 2 3/* 4 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19#include <sys/types.h> 20#include <sys/socket.h> 21#include <sys/wait.h> 22#include <netinet/in.h> 23#include <arpa/inet.h> 24#include <err.h> 25#include <errno.h> 26#include <fcntl.h> 27#include <poll.h> 28#include <pwd.h> 29#include <signal.h> 30#include <stdio.h> 31#include <stdlib.h> 32#include <string.h> 33#include <unistd.h> 34 35#include "mrt.h" 36#include "bgpd.h" 37#include "session.h" 38 39void sighdlr(int); 40void usage(void); 41int main(int, char *[]); 42int check_child(pid_t, const char *); 43int reconfigure(char *, struct bgpd_config *, struct mrt_head *, 44 struct peer **, struct filter_head *); 45int dispatch_imsg(struct imsgbuf *, int, struct mrt_head *); 46 47int rfd = -1; 48volatile sig_atomic_t mrtdump = 0; 49volatile sig_atomic_t quit = 0; 50volatile sig_atomic_t reconfig = 0; 51volatile sig_atomic_t sigchld = 0; 52struct imsgbuf ibuf_se; 53struct imsgbuf ibuf_rde; 54 55void 56sighdlr(int sig) 57{ 58 switch (sig) { 59 case SIGTERM: 60 case SIGINT: 61 quit = 1; 62 break; 63 case SIGCHLD: 64 sigchld = 1; 65 break; 66 case SIGHUP: 67 reconfig = 1; 68 break; 69 case SIGALRM: 70 case SIGUSR1: 71 mrtdump = 1; 72 break; 73 } 74} 75 76void 77usage(void) 78{ 79 extern char *__progname; 80 81 fprintf(stderr, "usage: %s [-dnv] ", __progname); 82 fprintf(stderr, "[-D macro=value] [-f file]\n"); 83 exit(1); 84} 85 86#define POLL_MAX 8 87#define PFD_PIPE_SESSION 0 88#define PFD_PIPE_ROUTE 1 89#define PFD_SOCK_ROUTE 2 90#define PFD_MRT_START 3 91 92int 93main(int argc, char *argv[]) 94{ 95 struct bgpd_config conf; 96 struct peer *peer_l; 97 struct mrt_head mrt_l; 98 struct network_head net_l; 99 struct filter_head *rules_l; 100 struct network *net; 101 struct filter_rule *r; 102 struct mrt *(mrt[POLL_MAX]); 103 struct pollfd pfd[POLL_MAX]; 104 pid_t io_pid = 0, rde_pid = 0, pid; 105 char *conffile; 106 int debug = 0; 107 int ch, csock, i, j, n, nfds, timeout; 108 int pipe_m2s[2]; 109 int pipe_m2r[2]; 110 int pipe_s2r[2]; 111 112 conffile = CONFFILE; 113 bgpd_process = PROC_MAIN; 114 115 log_init(1); /* log to stderr until daemonized */ 116 117 if ((rules_l = calloc(1, sizeof(struct filter_head))) == NULL) 118 err(1, NULL); 119 120 bzero(&conf, sizeof(conf)); 121 LIST_INIT(&mrt_l); 122 TAILQ_INIT(&net_l); 123 TAILQ_INIT(rules_l); 124 peer_l = NULL; 125 126 while ((ch = getopt(argc, argv, "dD:f:nv")) != -1) { 127 switch (ch) { 128 case 'd': 129 debug = 1; 130 break; 131 case 'D': 132 if (cmdline_symset(optarg) < 0) 133 log_warnx("could not parse macro definition %s", 134 optarg); 135 break; 136 case 'f': 137 conffile = optarg; 138 break; 139 case 'n': 140 conf.opts |= BGPD_OPT_NOACTION; 141 break; 142 case 'v': 143 if (conf.opts & BGPD_OPT_VERBOSE) 144 conf.opts |= BGPD_OPT_VERBOSE2; 145 conf.opts |= BGPD_OPT_VERBOSE; 146 break; 147 default: 148 usage(); 149 /* NOTREACHED */ 150 } 151 } 152 153 if (parse_config(conffile, &conf, &mrt_l, &peer_l, &net_l, rules_l)) 154 exit(1); 155 156 if (conf.opts & BGPD_OPT_NOACTION) { 157 if (conf.opts & BGPD_OPT_VERBOSE) 158 print_config(&conf, peer_l, rules_l); 159 else 160 fprintf(stderr, "configuration OK\n"); 161 exit(0); 162 } 163 164 if (geteuid()) 165 errx(1, "need root privileges"); 166 167 if (getpwnam(BGPD_USER) == NULL) 168 errx(1, "unknown user %s", BGPD_USER); 169 endpwent(); 170 171 log_init(debug); 172 173 if (!debug) 174 daemon(1, 0); 175 176 log_info("startup"); 177 178 if (pipe(pipe_m2s) == -1) 179 fatal("pipe"); 180 if (fcntl(pipe_m2s[0], F_SETFL, O_NONBLOCK) == -1 || 181 fcntl(pipe_m2s[1], F_SETFL, O_NONBLOCK) == -1) 182 fatal("fcntl"); 183 if (pipe(pipe_m2r) == -1) 184 fatal("pipe"); 185 if (fcntl(pipe_m2r[0], F_SETFL, O_NONBLOCK) == -1 || 186 fcntl(pipe_m2r[1], F_SETFL, O_NONBLOCK) == -1) 187 fatal("fcntl"); 188 if (pipe(pipe_s2r) == -1) 189 fatal("pipe"); 190 if (fcntl(pipe_s2r[0], F_SETFL, O_NONBLOCK) == -1 || 191 fcntl(pipe_s2r[1], F_SETFL, O_NONBLOCK) == -1) 192 fatal("fcntl"); 193 194 if ((csock = control_init()) == -1) 195 fatalx("control socket setup failed"); 196 197 /* fork children */ 198 rde_pid = rde_main(&conf, peer_l, &net_l, rules_l, pipe_m2r, pipe_s2r); 199 io_pid = session_main(&conf, peer_l, pipe_m2s, pipe_s2r); 200 201 setproctitle("parent"); 202 203 signal(SIGTERM, sighdlr); 204 signal(SIGINT, sighdlr); 205 signal(SIGCHLD, sighdlr); 206 signal(SIGHUP, sighdlr); 207 signal(SIGALRM, sighdlr); 208 signal(SIGUSR1, sighdlr); 209 210 close(pipe_m2s[1]); 211 close(pipe_m2r[1]); 212 close(pipe_s2r[0]); 213 close(pipe_s2r[1]); 214 close(csock); 215 216 imsg_init(&ibuf_se, pipe_m2s[0]); 217 imsg_init(&ibuf_rde, pipe_m2r[0]); 218 mrt_init(&ibuf_rde, &ibuf_se); 219 if ((rfd = kr_init(!(conf.flags & BGPD_FLAG_NO_FIB_UPDATE))) == -1) 220 quit = 1; 221 222 for (net = TAILQ_FIRST(&net_l); net != TAILQ_END(&net_l); 223 net = TAILQ_FIRST(&net_l)) { 224 TAILQ_REMOVE(&net_l, net, network_l); 225 free(net); 226 } 227 228 while ((r = TAILQ_FIRST(rules_l)) != NULL) { 229 TAILQ_REMOVE(rules_l, r, entries); 230 free(r); 231 } 232 233 while (quit == 0) { 234 pfd[PFD_PIPE_SESSION].fd = ibuf_se.sock; 235 pfd[PFD_PIPE_SESSION].events = POLLIN; 236 if (ibuf_se.w.queued) 237 pfd[PFD_PIPE_SESSION].events |= POLLOUT; 238 pfd[PFD_PIPE_ROUTE].fd = ibuf_rde.sock; 239 pfd[PFD_PIPE_ROUTE].events = POLLIN; 240 if (ibuf_rde.w.queued) 241 pfd[PFD_PIPE_ROUTE].events |= POLLOUT; 242 pfd[PFD_SOCK_ROUTE].fd = rfd; 243 pfd[PFD_SOCK_ROUTE].events = POLLIN; 244 i = PFD_MRT_START; 245 i = mrt_select(&mrt_l, pfd, mrt, i, POLL_MAX, &timeout); 246 247 if ((nfds = poll(pfd, i, INFTIM)) == -1) 248 if (errno != EINTR) { 249 log_warn("poll error"); 250 quit = 1; 251 } 252 253 if (nfds > 0 && (pfd[PFD_PIPE_SESSION].revents & POLLOUT)) 254 if ((n = msgbuf_write(&ibuf_se.w)) < 0) { 255 log_warn("pipe write error (to SE)"); 256 quit = 1; 257 } 258 259 if (nfds > 0 && (pfd[PFD_PIPE_ROUTE].revents & POLLOUT)) 260 if ((n = msgbuf_write(&ibuf_rde.w)) < 0) { 261 log_warn("pipe write error (to RDE)"); 262 quit = 1; 263 } 264 265 if (nfds > 0 && pfd[PFD_PIPE_SESSION].revents & POLLIN) { 266 nfds--; 267 if (dispatch_imsg(&ibuf_se, PFD_PIPE_SESSION, 268 &mrt_l) == -1) 269 quit = 1; 270 } 271 272 if (nfds > 0 && pfd[PFD_PIPE_ROUTE].revents & POLLIN) { 273 nfds--; 274 if (dispatch_imsg(&ibuf_rde, PFD_PIPE_ROUTE, 275 &mrt_l) == -1) 276 quit = 1; 277 } 278 279 if (nfds > 0 && pfd[PFD_SOCK_ROUTE].revents & POLLIN) { 280 nfds--; 281 if (kr_dispatch_msg() == -1) 282 quit = 1; 283 } 284 285 for (j = PFD_MRT_START; j < i && nfds > 0 ; j++) { 286 if (pfd[j].revents & POLLOUT) { 287 if ((n = mrt_write(mrt[j])) < 0) { 288 log_warn("mrt write error"); 289 } 290 } 291 } 292 293 if (reconfig) { 294 log_info("rereading config"); 295 reconfigure(conffile, &conf, &mrt_l, &peer_l, rules_l); 296 reconfig = 0; 297 } 298 299 if (sigchld) { 300 if (check_child(io_pid, "session engine")) 301 quit = 1; 302 if (check_child(rde_pid, "route decision engine")) 303 quit = 1; 304 sigchld = 0; 305 } 306 307 if (mrtdump == 1) { 308 mrt_handler(&mrt_l); 309 mrtdump = 0; 310 } 311 } 312 313 signal(SIGCHLD, SIG_IGN); 314 315 if (io_pid) 316 kill(io_pid, SIGTERM); 317 318 if (rde_pid) 319 kill(rde_pid, SIGTERM); 320 321 do { 322 pid = waitpid(-1, NULL, WNOHANG); 323 } while (pid > 0 || (pid == -1 && errno == EINTR)); 324 325 free(rules_l); 326 control_cleanup(); 327 kr_shutdown(); 328 329 log_info("Terminating"); 330 return (0); 331} 332 333int 334check_child(pid_t pid, const char *pname) 335{ 336 int status; 337 338 if (waitpid(pid, &status, WNOHANG) > 0) { 339 if (WIFEXITED(status)) { 340 log_warnx("Lost child: %s exited", pname); 341 return (1); 342 } 343 if (WIFSIGNALED(status)) { 344 log_warnx("Lost child: %s terminated; signal %d", 345 pname, WTERMSIG(status)); 346 return (1); 347 } 348 } 349 350 return (0); 351} 352 353int 354reconfigure(char *conffile, struct bgpd_config *conf, struct mrt_head *mrt_l, 355 struct peer **peer_l, struct filter_head *rules_l) 356{ 357 struct network_head net_l; 358 struct network *n; 359 struct peer *p; 360 struct filter_rule *r; 361 362 if (parse_config(conffile, conf, mrt_l, peer_l, &net_l, rules_l)) { 363 log_warnx("config file %s has errors, not reloading", 364 conffile); 365 return (-1); 366 } 367 368 if (imsg_compose(&ibuf_se, IMSG_RECONF_CONF, 0, 369 conf, sizeof(struct bgpd_config)) == -1) 370 return (-1); 371 if (imsg_compose(&ibuf_rde, IMSG_RECONF_CONF, 0, 372 conf, sizeof(struct bgpd_config)) == -1) 373 return (-1); 374 for (p = *peer_l; p != NULL; p = p->next) { 375 if (imsg_compose(&ibuf_se, IMSG_RECONF_PEER, p->conf.id, 376 &p->conf, sizeof(struct peer_config)) == -1) 377 return (-1); 378 if (imsg_compose(&ibuf_rde, IMSG_RECONF_PEER, p->conf.id, 379 &p->conf, sizeof(struct peer_config)) == -1) 380 return (-1); 381 } 382 for (n = TAILQ_FIRST(&net_l); n != TAILQ_END(&net_l); 383 n = TAILQ_FIRST(&net_l)) { 384 if (imsg_compose(&ibuf_rde, IMSG_RECONF_NETWORK, 0, 385 &n->net, sizeof(struct network_config)) == -1) 386 return (-1); 387 TAILQ_REMOVE(&net_l, n, network_l); 388 free(n); 389 } 390 for (r = TAILQ_FIRST(rules_l); r != NULL; r = TAILQ_FIRST(rules_l)) { 391 if (imsg_compose(&ibuf_rde, IMSG_RECONF_FILTER, 0, 392 r, sizeof(struct filter_rule)) == -1) 393 return (-1); 394 TAILQ_REMOVE(rules_l, r, entries); 395 free(r); 396 } 397 if (imsg_compose(&ibuf_se, IMSG_RECONF_DONE, 0, NULL, 0) == -1 || 398 imsg_compose(&ibuf_rde, IMSG_RECONF_DONE, 0, NULL, 0) == -1) 399 return (-1); 400 401 return (0); 402} 403 404int 405dispatch_imsg(struct imsgbuf *ibuf, int idx, struct mrt_head *mrt_l) 406{ 407 struct imsg imsg; 408 int n; 409 410 if ((n = imsg_read(ibuf)) == -1) 411 return (-1); 412 413 if (n == 0) { /* connection closed */ 414 log_warnx("dispatch_imsg in main: pipe closed"); 415 return (-1); 416 } 417 418 for (;;) { 419 if ((n = imsg_get(ibuf, &imsg)) == -1) 420 return (-1); 421 422 if (n == 0) 423 break; 424 425 switch (imsg.hdr.type) { 426 case IMSG_MRT_MSG: 427 case IMSG_MRT_END: 428 if (mrt_queue(mrt_l, &imsg) == -1) 429 log_warnx("mrt_queue failed."); 430 break; 431 case IMSG_KROUTE_CHANGE: 432 if (idx != PFD_PIPE_ROUTE) 433 log_warnx("route request not from RDE"); 434 else if (kr_change(imsg.data)) 435 return (-1); 436 break; 437 case IMSG_KROUTE_DELETE: 438 if (idx != PFD_PIPE_ROUTE) 439 log_warnx("route request not from RDE"); 440 else if (kr_delete(imsg.data)) 441 return (-1); 442 break; 443 case IMSG_NEXTHOP_ADD: 444 if (idx != PFD_PIPE_ROUTE) 445 log_warnx("nexthop request not from RDE"); 446 else 447 if (imsg.hdr.len != IMSG_HEADER_SIZE + 448 sizeof(struct bgpd_addr)) 449 log_warnx("wrong imsg len"); 450 else if (kr_nexthop_add(imsg.data) == -1) 451 return (-1); 452 break; 453 case IMSG_NEXTHOP_REMOVE: 454 if (idx != PFD_PIPE_ROUTE) 455 log_warnx("nexthop request not from RDE"); 456 else 457 if (imsg.hdr.len != IMSG_HEADER_SIZE + 458 sizeof(struct bgpd_addr)) 459 log_warnx("wrong imsg len"); 460 else kr_nexthop_delete(imsg.data); 461 break; 462 case IMSG_CTL_RELOAD: 463 if (idx != PFD_PIPE_SESSION) 464 log_warnx("reload request not from SE"); 465 else 466 reconfig = 1; 467 break; 468 case IMSG_CTL_FIB_COUPLE: 469 if (idx != PFD_PIPE_SESSION) 470 log_warnx("couple request not from SE"); 471 else 472 kr_fib_couple(); 473 break; 474 case IMSG_CTL_FIB_DECOUPLE: 475 if (idx != PFD_PIPE_SESSION) 476 log_warnx("decouple request not from SE"); 477 else 478 kr_fib_decouple(); 479 break; 480 case IMSG_CTL_KROUTE: 481 case IMSG_CTL_KROUTE_ADDR: 482 case IMSG_CTL_SHOW_NEXTHOP: 483 case IMSG_CTL_SHOW_INTERFACE: 484 if (idx != PFD_PIPE_SESSION) 485 log_warnx("kroute request not from SE"); 486 else 487 kr_show_route(&imsg); 488 break; 489 default: 490 break; 491 } 492 imsg_free(&imsg); 493 } 494 return (0); 495} 496 497void 498send_nexthop_update(struct kroute_nexthop *msg) 499{ 500 char *gw = NULL; 501 502 if (msg->gateway.af) 503 if (asprintf(&gw, ": via %s", 504 log_addr(&msg->gateway)) == -1) { 505 log_warn("send_nexthop_update"); 506 quit = 1; 507 } 508 509 log_info("nexthop %s now %s%s%s", log_addr(&msg->nexthop), 510 msg->valid ? "valid" : "invalid", 511 msg->connected ? ": directly connected" : "", 512 msg->gateway.af ? gw : ""); 513 514 free(gw); 515 516 if (imsg_compose(&ibuf_rde, IMSG_NEXTHOP_UPDATE, 0, 517 msg, sizeof(struct kroute_nexthop)) == -1) 518 quit = 1; 519} 520 521void 522send_imsg_session(int type, pid_t pid, void *data, u_int16_t datalen) 523{ 524 imsg_compose_pid(&ibuf_se, type, pid, data, datalen); 525} 526 527 528