1 /* $OpenBSD: control.c,v 1.117 2024/04/22 09:36:04 claudio 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/stat.h> 21 #include <sys/socket.h> 22 #include <sys/un.h> 23 #include <errno.h> 24 #include <stdlib.h> 25 #include <string.h> 26 #include <unistd.h> 27 28 #include "bgpd.h" 29 #include "session.h" 30 #include "log.h" 31 32 TAILQ_HEAD(ctl_conns, ctl_conn) ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns); 33 34 #define CONTROL_BACKLOG 5 35 36 struct ctl_conn *control_connbyfd(int); 37 struct ctl_conn *control_connbypid(pid_t); 38 int control_close(struct ctl_conn *); 39 void control_result(struct ctl_conn *, u_int); 40 ssize_t imsg_read_nofd(struct imsgbuf *); 41 42 int 43 control_check(char *path) 44 { 45 struct sockaddr_un sa_un; 46 int fd; 47 48 memset(&sa_un, 0, sizeof(sa_un)); 49 sa_un.sun_family = AF_UNIX; 50 strlcpy(sa_un.sun_path, path, sizeof(sa_un.sun_path)); 51 52 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0)) == -1) { 53 log_warn("%s: socket", __func__); 54 return (-1); 55 } 56 57 if (connect(fd, (struct sockaddr *)&sa_un, sizeof(sa_un)) == 0) { 58 log_warnx("control socket %s already in use", path); 59 close(fd); 60 return (-1); 61 } 62 63 close(fd); 64 65 return (0); 66 } 67 68 int 69 control_init(int restricted, char *path) 70 { 71 struct sockaddr_un sa_un; 72 int fd; 73 mode_t old_umask, mode; 74 75 if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK, 76 0)) == -1) { 77 log_warn("control_init: socket"); 78 return (-1); 79 } 80 81 memset(&sa_un, 0, sizeof(sa_un)); 82 sa_un.sun_family = AF_UNIX; 83 if (strlcpy(sa_un.sun_path, path, sizeof(sa_un.sun_path)) >= 84 sizeof(sa_un.sun_path)) { 85 log_warn("control_init: socket name too long"); 86 close(fd); 87 return (-1); 88 } 89 90 if (unlink(path) == -1) 91 if (errno != ENOENT) { 92 log_warn("control_init: unlink %s", path); 93 close(fd); 94 return (-1); 95 } 96 97 if (restricted) { 98 old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH); 99 mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH; 100 } else { 101 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 102 mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP; 103 } 104 105 if (bind(fd, (struct sockaddr *)&sa_un, sizeof(sa_un)) == -1) { 106 log_warn("control_init: bind: %s", path); 107 close(fd); 108 umask(old_umask); 109 return (-1); 110 } 111 112 umask(old_umask); 113 114 if (chmod(path, mode) == -1) { 115 log_warn("control_init: chmod: %s", path); 116 close(fd); 117 unlink(path); 118 return (-1); 119 } 120 121 return (fd); 122 } 123 124 int 125 control_listen(int fd) 126 { 127 if (fd != -1 && listen(fd, CONTROL_BACKLOG) == -1) { 128 log_warn("control_listen: listen"); 129 return (-1); 130 } 131 132 return (0); 133 } 134 135 void 136 control_shutdown(int fd) 137 { 138 close(fd); 139 } 140 141 size_t 142 control_fill_pfds(struct pollfd *pfd, size_t size) 143 { 144 struct ctl_conn *ctl_conn; 145 size_t i = 0; 146 147 TAILQ_FOREACH(ctl_conn, &ctl_conns, entry) { 148 pfd[i].fd = ctl_conn->imsgbuf.fd; 149 pfd[i].events = POLLIN; 150 if (ctl_conn->imsgbuf.w.queued > 0) 151 pfd[i].events |= POLLOUT; 152 i++; 153 } 154 return i; 155 } 156 157 unsigned int 158 control_accept(int listenfd, int restricted) 159 { 160 int connfd; 161 socklen_t len; 162 struct sockaddr_un sa_un; 163 struct ctl_conn *ctl_conn; 164 165 len = sizeof(sa_un); 166 if ((connfd = accept4(listenfd, 167 (struct sockaddr *)&sa_un, &len, 168 SOCK_NONBLOCK | SOCK_CLOEXEC)) == -1) { 169 if (errno == ENFILE || errno == EMFILE) { 170 pauseaccept = getmonotime(); 171 return (0); 172 } else if (errno != EWOULDBLOCK && errno != EINTR && 173 errno != ECONNABORTED) 174 log_warn("control_accept: accept"); 175 return (0); 176 } 177 178 if ((ctl_conn = calloc(1, sizeof(struct ctl_conn))) == NULL) { 179 log_warn("control_accept"); 180 close(connfd); 181 return (0); 182 } 183 184 imsg_init(&ctl_conn->imsgbuf, connfd); 185 ctl_conn->restricted = restricted; 186 187 TAILQ_INSERT_TAIL(&ctl_conns, ctl_conn, entry); 188 189 return (1); 190 } 191 192 struct ctl_conn * 193 control_connbyfd(int fd) 194 { 195 struct ctl_conn *c; 196 197 TAILQ_FOREACH(c, &ctl_conns, entry) { 198 if (c->imsgbuf.fd == fd) 199 break; 200 } 201 202 return (c); 203 } 204 205 struct ctl_conn * 206 control_connbypid(pid_t pid) 207 { 208 struct ctl_conn *c; 209 210 TAILQ_FOREACH(c, &ctl_conns, entry) { 211 if (c->imsgbuf.pid == pid) 212 break; 213 } 214 215 return (c); 216 } 217 218 int 219 control_close(struct ctl_conn *c) 220 { 221 if (c->terminate && c->imsgbuf.pid) 222 imsg_ctl_rde_msg(IMSG_CTL_TERMINATE, 0, c->imsgbuf.pid); 223 224 msgbuf_clear(&c->imsgbuf.w); 225 TAILQ_REMOVE(&ctl_conns, c, entry); 226 227 close(c->imsgbuf.fd); 228 free(c); 229 pauseaccept = 0; 230 return (1); 231 } 232 233 int 234 control_dispatch_msg(struct pollfd *pfd, struct peer_head *peers) 235 { 236 struct imsg imsg; 237 struct ctl_neighbor neighbor; 238 struct ctl_show_rib_request ribreq; 239 struct ctl_conn *c; 240 struct peer *p; 241 ssize_t n; 242 uint32_t type; 243 pid_t pid; 244 int verbose, matched; 245 246 if ((c = control_connbyfd(pfd->fd)) == NULL) { 247 log_warn("control_dispatch_msg: fd %d: not found", pfd->fd); 248 return (0); 249 } 250 251 if (pfd->revents & POLLOUT) { 252 if (msgbuf_write(&c->imsgbuf.w) <= 0 && errno != EAGAIN) 253 return control_close(c); 254 if (c->throttled && c->imsgbuf.w.queued < CTL_MSG_LOW_MARK) { 255 if (imsg_ctl_rde_msg(IMSG_XON, 0, c->imsgbuf.pid) != -1) 256 c->throttled = 0; 257 } 258 } 259 260 if (!(pfd->revents & POLLIN)) 261 return (0); 262 263 if (((n = imsg_read_nofd(&c->imsgbuf)) == -1 && errno != EAGAIN) || 264 n == 0) 265 return control_close(c); 266 267 for (;;) { 268 if ((n = imsg_get(&c->imsgbuf, &imsg)) == -1) 269 return control_close(c); 270 271 if (n == 0) 272 break; 273 274 type = imsg_get_type(&imsg); 275 pid = imsg_get_pid(&imsg); 276 if (c->restricted) { 277 switch (type) { 278 case IMSG_CTL_SHOW_NEIGHBOR: 279 case IMSG_CTL_SHOW_NEXTHOP: 280 case IMSG_CTL_SHOW_INTERFACE: 281 case IMSG_CTL_SHOW_RIB_MEM: 282 case IMSG_CTL_SHOW_TERSE: 283 case IMSG_CTL_SHOW_TIMER: 284 case IMSG_CTL_SHOW_NETWORK: 285 case IMSG_CTL_SHOW_FLOWSPEC: 286 case IMSG_CTL_SHOW_RIB: 287 case IMSG_CTL_SHOW_RIB_PREFIX: 288 case IMSG_CTL_SHOW_SET: 289 case IMSG_CTL_SHOW_RTR: 290 break; 291 default: 292 /* clear imsg type to prevent processing */ 293 type = IMSG_NONE; 294 control_result(c, CTL_RES_DENIED); 295 break; 296 } 297 } 298 299 /* 300 * TODO: this is wrong and shoud work the other way around. 301 * The imsg.hdr.pid is from the remote end and should not 302 * be trusted. 303 */ 304 c->imsgbuf.pid = pid; 305 switch (type) { 306 case IMSG_NONE: 307 /* message was filtered out, nothing to do */ 308 break; 309 case IMSG_CTL_FIB_COUPLE: 310 case IMSG_CTL_FIB_DECOUPLE: 311 imsg_ctl_parent(&imsg); 312 break; 313 case IMSG_CTL_SHOW_TERSE: 314 RB_FOREACH(p, peer_head, peers) 315 imsg_compose(&c->imsgbuf, 316 IMSG_CTL_SHOW_NEIGHBOR, 0, 0, -1, 317 p, sizeof(struct peer)); 318 imsg_compose(&c->imsgbuf, IMSG_CTL_END, 0, 0, -1, 319 NULL, 0); 320 break; 321 case IMSG_CTL_SHOW_NEIGHBOR: 322 if (imsg_get_data(&imsg, &neighbor, 323 sizeof(neighbor)) == -1) 324 memset(&neighbor, 0, sizeof(neighbor)); 325 326 matched = 0; 327 RB_FOREACH(p, peer_head, peers) { 328 if (!peer_matched(p, &neighbor)) 329 continue; 330 331 matched = 1; 332 if (!neighbor.show_timers) { 333 imsg_ctl_rde_msg(type, 334 p->conf.id, pid); 335 } else { 336 u_int i; 337 time_t d; 338 struct ctl_timer ct; 339 340 imsg_compose(&c->imsgbuf, 341 IMSG_CTL_SHOW_NEIGHBOR, 342 0, 0, -1, p, sizeof(*p)); 343 for (i = 1; i < Timer_Max; i++) { 344 if (!timer_running(&p->timers, 345 i, &d)) 346 continue; 347 ct.type = i; 348 ct.val = d; 349 imsg_compose(&c->imsgbuf, 350 IMSG_CTL_SHOW_TIMER, 351 0, 0, -1, &ct, sizeof(ct)); 352 } 353 } 354 } 355 if (!matched && RB_EMPTY(peers)) { 356 control_result(c, CTL_RES_NOSUCHPEER); 357 } else if (!neighbor.show_timers) { 358 imsg_ctl_rde_msg(IMSG_CTL_END, 0, pid); 359 } else { 360 imsg_compose(&c->imsgbuf, IMSG_CTL_END, 0, 0, 361 -1, NULL, 0); 362 } 363 break; 364 case IMSG_CTL_NEIGHBOR_UP: 365 case IMSG_CTL_NEIGHBOR_DOWN: 366 case IMSG_CTL_NEIGHBOR_CLEAR: 367 case IMSG_CTL_NEIGHBOR_RREFRESH: 368 case IMSG_CTL_NEIGHBOR_DESTROY: 369 if (imsg_get_data(&imsg, &neighbor, 370 sizeof(neighbor)) == -1) { 371 log_warnx("got IMSG_CTL_NEIGHBOR_ with " 372 "wrong length"); 373 break; 374 } 375 376 matched = 0; 377 RB_FOREACH(p, peer_head, peers) { 378 if (!peer_matched(p, &neighbor)) 379 continue; 380 381 matched = 1; 382 383 switch (type) { 384 case IMSG_CTL_NEIGHBOR_UP: 385 bgp_fsm(p, EVNT_START); 386 p->conf.down = 0; 387 p->conf.reason[0] = '\0'; 388 p->IdleHoldTime = 389 INTERVAL_IDLE_HOLD_INITIAL; 390 p->errcnt = 0; 391 control_result(c, CTL_RES_OK); 392 break; 393 case IMSG_CTL_NEIGHBOR_DOWN: 394 neighbor.reason[ 395 sizeof(neighbor.reason) - 1] = '\0'; 396 p->conf.down = 1; 397 session_stop(p, ERR_CEASE_ADMIN_DOWN, 398 neighbor.reason); 399 control_result(c, CTL_RES_OK); 400 break; 401 case IMSG_CTL_NEIGHBOR_CLEAR: 402 neighbor.reason[ 403 sizeof(neighbor.reason) - 1] = '\0'; 404 p->IdleHoldTime = 405 INTERVAL_IDLE_HOLD_INITIAL; 406 p->errcnt = 0; 407 if (!p->conf.down) { 408 session_stop(p, 409 ERR_CEASE_ADMIN_RESET, 410 neighbor.reason); 411 timer_set(&p->timers, 412 Timer_IdleHold, 413 SESSION_CLEAR_DELAY); 414 } else { 415 session_stop(p, 416 ERR_CEASE_ADMIN_DOWN, 417 neighbor.reason); 418 } 419 control_result(c, CTL_RES_OK); 420 break; 421 case IMSG_CTL_NEIGHBOR_RREFRESH: 422 if (session_neighbor_rrefresh(p)) 423 control_result(c, 424 CTL_RES_NOCAP); 425 else 426 control_result(c, CTL_RES_OK); 427 break; 428 case IMSG_CTL_NEIGHBOR_DESTROY: 429 if (!p->template) 430 control_result(c, 431 CTL_RES_BADPEER); 432 else if (p->state != STATE_IDLE) 433 control_result(c, 434 CTL_RES_BADSTATE); 435 else { 436 /* 437 * Mark as deleted, will be 438 * collected on next poll loop. 439 */ 440 p->reconf_action = 441 RECONF_DELETE; 442 control_result(c, CTL_RES_OK); 443 } 444 break; 445 default: 446 fatal("king bula wants more humppa"); 447 } 448 } 449 if (!matched) 450 control_result(c, CTL_RES_NOSUCHPEER); 451 break; 452 case IMSG_CTL_RELOAD: 453 case IMSG_CTL_SHOW_INTERFACE: 454 case IMSG_CTL_SHOW_FIB_TABLES: 455 case IMSG_CTL_SHOW_RTR: 456 imsg_ctl_parent(&imsg); 457 break; 458 case IMSG_CTL_KROUTE: 459 case IMSG_CTL_KROUTE_ADDR: 460 case IMSG_CTL_SHOW_NEXTHOP: 461 imsg_ctl_parent(&imsg); 462 break; 463 case IMSG_CTL_SHOW_RIB: 464 case IMSG_CTL_SHOW_RIB_PREFIX: 465 if (imsg_get_data(&imsg, &ribreq, sizeof(ribreq)) == 466 -1) { 467 log_warnx("got IMSG_CTL_SHOW_RIB with " 468 "wrong length"); 469 break; 470 } 471 472 /* check if at least one neighbor exists */ 473 RB_FOREACH(p, peer_head, peers) 474 if (peer_matched(p, &ribreq.neighbor)) 475 break; 476 if (p == NULL && RB_EMPTY(peers)) { 477 control_result(c, CTL_RES_NOSUCHPEER); 478 break; 479 } 480 481 if (type == IMSG_CTL_SHOW_RIB_PREFIX && 482 ribreq.prefix.aid == AID_UNSPEC) { 483 /* malformed request, must specify af */ 484 control_result(c, CTL_RES_PARSE_ERROR); 485 break; 486 } 487 488 c->terminate = 1; 489 imsg_ctl_rde(&imsg); 490 break; 491 case IMSG_CTL_SHOW_NETWORK: 492 case IMSG_CTL_SHOW_FLOWSPEC: 493 c->terminate = 1; 494 /* FALLTHROUGH */ 495 case IMSG_CTL_SHOW_RIB_MEM: 496 case IMSG_CTL_SHOW_SET: 497 imsg_ctl_rde(&imsg); 498 break; 499 case IMSG_NETWORK_ADD: 500 case IMSG_NETWORK_ASPATH: 501 case IMSG_NETWORK_ATTR: 502 case IMSG_NETWORK_REMOVE: 503 case IMSG_NETWORK_FLUSH: 504 case IMSG_NETWORK_DONE: 505 case IMSG_FLOWSPEC_ADD: 506 case IMSG_FLOWSPEC_REMOVE: 507 case IMSG_FLOWSPEC_DONE: 508 case IMSG_FLOWSPEC_FLUSH: 509 case IMSG_FILTER_SET: 510 imsg_ctl_rde(&imsg); 511 break; 512 case IMSG_CTL_LOG_VERBOSE: 513 if (imsg_get_data(&imsg, &verbose, sizeof(verbose)) == 514 -1) 515 break; 516 517 /* forward to other processes */ 518 imsg_ctl_parent(&imsg); 519 imsg_ctl_rde(&imsg); 520 log_setverbose(verbose); 521 break; 522 default: 523 break; 524 } 525 imsg_free(&imsg); 526 } 527 528 return (0); 529 } 530 531 int 532 control_imsg_relay(struct imsg *imsg, struct peer *p) 533 { 534 struct ctl_conn *c; 535 uint32_t type; 536 pid_t pid; 537 538 type = imsg_get_type(imsg); 539 pid = imsg_get_pid(imsg); 540 541 if ((c = control_connbypid(pid)) == NULL) 542 return (0); 543 544 /* special handling for peers since only the stats are sent from RDE */ 545 if (type == IMSG_CTL_SHOW_NEIGHBOR) { 546 struct rde_peer_stats stats; 547 548 if (p == NULL) { 549 log_warnx("%s: no such peer: id=%u", __func__, 550 imsg_get_id(imsg)); 551 return (0); 552 } 553 if (imsg_get_data(imsg, &stats, sizeof(stats)) == -1) { 554 log_warnx("%s: imsg_get_data", __func__); 555 return (0); 556 } 557 p->stats.prefix_cnt = stats.prefix_cnt; 558 p->stats.prefix_out_cnt = stats.prefix_out_cnt; 559 p->stats.prefix_rcvd_update = stats.prefix_rcvd_update; 560 p->stats.prefix_rcvd_withdraw = stats.prefix_rcvd_withdraw; 561 p->stats.prefix_rcvd_eor = stats.prefix_rcvd_eor; 562 p->stats.prefix_sent_update = stats.prefix_sent_update; 563 p->stats.prefix_sent_withdraw = stats.prefix_sent_withdraw; 564 p->stats.prefix_sent_eor = stats.prefix_sent_eor; 565 p->stats.pending_update = stats.pending_update; 566 p->stats.pending_withdraw = stats.pending_withdraw; 567 568 return imsg_compose(&c->imsgbuf, type, 0, pid, -1, 569 p, sizeof(*p)); 570 } 571 572 /* if command finished no need to send exit message */ 573 if (type == IMSG_CTL_END || type == IMSG_CTL_RESULT) 574 c->terminate = 0; 575 576 if (!c->throttled && c->imsgbuf.w.queued > CTL_MSG_HIGH_MARK) { 577 if (imsg_ctl_rde_msg(IMSG_XOFF, 0, pid) != -1) 578 c->throttled = 1; 579 } 580 581 return (imsg_forward(&c->imsgbuf, imsg)); 582 } 583 584 void 585 control_result(struct ctl_conn *c, u_int code) 586 { 587 imsg_compose(&c->imsgbuf, IMSG_CTL_RESULT, 0, c->imsgbuf.pid, -1, 588 &code, sizeof(code)); 589 } 590 591 /* This should go into libutil, from smtpd/mproc.c */ 592 ssize_t 593 imsg_read_nofd(struct imsgbuf *imsgbuf) 594 { 595 ssize_t n; 596 char *buf; 597 size_t len; 598 599 buf = imsgbuf->r.buf + imsgbuf->r.wpos; 600 len = sizeof(imsgbuf->r.buf) - imsgbuf->r.wpos; 601 602 while ((n = recv(imsgbuf->fd, buf, len, 0)) == -1) { 603 if (errno != EINTR) 604 return (n); 605 } 606 607 imsgbuf->r.wpos += n; 608 return (n); 609 } 610