1 /* $OpenBSD: hce.c,v 1.53 2009/06/05 23:39:51 pyr Exp $ */ 2 3 /* 4 * Copyright (c) 2006 Pierre-Yves Ritschard <pyr@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/param.h> 20 #include <sys/queue.h> 21 #include <sys/time.h> 22 #include <sys/stat.h> 23 #include <sys/socket.h> 24 #include <sys/un.h> 25 26 #include <net/if.h> 27 #include <netinet/in_systm.h> 28 #include <netinet/in.h> 29 #include <netinet/ip.h> 30 31 #include <errno.h> 32 #include <event.h> 33 #include <fcntl.h> 34 #include <stdlib.h> 35 #include <string.h> 36 #include <unistd.h> 37 #include <err.h> 38 #include <pwd.h> 39 40 #include <openssl/ssl.h> 41 42 #include "relayd.h" 43 44 __dead void hce_shutdown(void); 45 void hce_sig_handler(int sig, short, void *); 46 void hce_dispatch_imsg(int, short, void *); 47 void hce_dispatch_parent(int, short, void *); 48 void hce_launch_checks(int, short, void *); 49 void hce_setup_events(void); 50 void hce_disable_events(void); 51 52 static struct relayd *env = NULL; 53 struct imsgev *iev_pfe; 54 struct imsgev *iev_main; 55 int running = 0; 56 57 void 58 hce_sig_handler(int sig, short event, void *arg) 59 { 60 switch (sig) { 61 case SIGINT: 62 case SIGTERM: 63 hce_shutdown(); 64 break; 65 default: 66 fatalx("hce_sig_handler: unexpected signal"); 67 } 68 } 69 70 pid_t 71 hce(struct relayd *x_env, int pipe_parent2pfe[2], int pipe_parent2hce[2], 72 int pipe_parent2relay[RELAY_MAXPROC][2], int pipe_pfe2hce[2], 73 int pipe_pfe2relay[RELAY_MAXPROC][2]) 74 { 75 pid_t pid; 76 struct passwd *pw; 77 int i; 78 struct event ev_sigint; 79 struct event ev_sigterm; 80 81 switch (pid = fork()) { 82 case -1: 83 fatal("hce: cannot fork"); 84 case 0: 85 break; 86 default: 87 return (pid); 88 } 89 90 env = x_env; 91 purge_config(env, PURGE_RDRS|PURGE_RELAYS|PURGE_PROTOS); 92 93 if ((pw = getpwnam(RELAYD_USER)) == NULL) 94 fatal("hce: getpwnam"); 95 96 #ifndef DEBUG 97 if (chroot(pw->pw_dir) == -1) 98 fatal("hce: chroot"); 99 if (chdir("/") == -1) 100 fatal("hce: chdir(\"/\")"); 101 #else 102 #warning disabling privilege revocation and chroot in DEBUG mode 103 #endif 104 105 setproctitle("host check engine"); 106 relayd_process = PROC_HCE; 107 108 /* this is needed for icmp tests */ 109 icmp_init(env); 110 111 #ifndef DEBUG 112 if (setgroups(1, &pw->pw_gid) || 113 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) || 114 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid)) 115 fatal("hce: can't drop privileges"); 116 #endif 117 118 event_init(); 119 120 if ((iev_pfe = calloc(1, sizeof(struct imsgev))) == NULL || 121 (iev_main = calloc(1, sizeof(struct imsgev))) == NULL) 122 fatal("hce"); 123 imsg_init(&iev_pfe->ibuf, pipe_pfe2hce[0]); 124 iev_pfe->handler = hce_dispatch_imsg; 125 imsg_init(&iev_main->ibuf, pipe_parent2hce[1]); 126 iev_main->handler = hce_dispatch_parent; 127 128 iev_pfe->events = EV_READ; 129 event_set(&iev_pfe->ev, iev_pfe->ibuf.fd, iev_pfe->events, 130 iev_pfe->handler, iev_pfe); 131 event_add(&iev_pfe->ev, NULL); 132 133 iev_main->events = EV_READ; 134 event_set(&iev_main->ev, iev_main->ibuf.fd, iev_main->events, 135 iev_main->handler, iev_main); 136 event_add(&iev_main->ev, NULL); 137 138 signal_set(&ev_sigint, SIGINT, hce_sig_handler, NULL); 139 signal_set(&ev_sigterm, SIGTERM, hce_sig_handler, NULL); 140 signal_add(&ev_sigint, NULL); 141 signal_add(&ev_sigterm, NULL); 142 signal(SIGPIPE, SIG_IGN); 143 signal(SIGHUP, SIG_IGN); 144 145 /* setup pipes */ 146 close(pipe_pfe2hce[1]); 147 close(pipe_parent2hce[0]); 148 close(pipe_parent2pfe[0]); 149 close(pipe_parent2pfe[1]); 150 for (i = 0; i < env->sc_prefork_relay; i++) { 151 close(pipe_parent2relay[i][0]); 152 close(pipe_parent2relay[i][1]); 153 close(pipe_pfe2relay[i][0]); 154 close(pipe_pfe2relay[i][1]); 155 } 156 157 hce_setup_events(); 158 event_dispatch(); 159 hce_shutdown(); 160 161 return (0); 162 } 163 164 void 165 hce_setup_events(void) 166 { 167 struct timeval tv; 168 struct table *table; 169 170 snmp_init(env, iev_main); 171 172 if (!TAILQ_EMPTY(env->sc_tables)) { 173 evtimer_set(&env->sc_ev, hce_launch_checks, env); 174 bzero(&tv, sizeof(tv)); 175 evtimer_add(&env->sc_ev, &tv); 176 } 177 178 if (env->sc_flags & F_SSL) { 179 ssl_init(env); 180 TAILQ_FOREACH(table, env->sc_tables, entry) { 181 if (!(table->conf.flags & F_SSL)) 182 continue; 183 table->ssl_ctx = ssl_ctx_create(env); 184 } 185 } 186 } 187 188 void 189 hce_disable_events(void) 190 { 191 struct table *table; 192 struct host *host; 193 194 evtimer_del(&env->sc_ev); 195 TAILQ_FOREACH(table, env->sc_tables, entry) { 196 TAILQ_FOREACH(host, &table->hosts, entry) { 197 host->he = HCE_ABORT; 198 event_del(&host->cte.ev); 199 close(host->cte.s); 200 } 201 } 202 if (env->sc_has_icmp) { 203 event_del(&env->sc_icmp_send.ev); 204 event_del(&env->sc_icmp_recv.ev); 205 } 206 if (env->sc_has_icmp6) { 207 event_del(&env->sc_icmp6_send.ev); 208 event_del(&env->sc_icmp6_recv.ev); 209 } 210 } 211 212 void 213 hce_launch_checks(int fd, short event, void *arg) 214 { 215 struct host *host; 216 struct table *table; 217 struct timeval tv; 218 219 /* 220 * notify pfe checks are done and schedule next check 221 */ 222 imsg_compose_event(iev_pfe, IMSG_SYNC, 0, 0, -1, NULL, 0); 223 TAILQ_FOREACH(table, env->sc_tables, entry) { 224 TAILQ_FOREACH(host, &table->hosts, entry) { 225 if ((host->flags & F_CHECK_DONE) == 0) 226 host->he = HCE_INTERVAL_TIMEOUT; 227 host->flags &= ~(F_CHECK_SENT|F_CHECK_DONE); 228 event_del(&host->cte.ev); 229 } 230 } 231 232 if (gettimeofday(&tv, NULL) == -1) 233 fatal("hce_launch_checks: gettimeofday"); 234 235 TAILQ_FOREACH(table, env->sc_tables, entry) { 236 if (table->conf.flags & F_DISABLE) 237 continue; 238 if (table->conf.skip_cnt) { 239 if (table->skipped++ > table->conf.skip_cnt) 240 table->skipped = 0; 241 if (table->skipped != 1) 242 continue; 243 } 244 if (table->conf.check == CHECK_NOCHECK) 245 fatalx("hce_launch_checks: unknown check type"); 246 247 TAILQ_FOREACH(host, &table->hosts, entry) { 248 if (host->flags & F_DISABLE || host->conf.parentid) 249 continue; 250 switch (table->conf.check) { 251 case CHECK_ICMP: 252 schedule_icmp(env, host); 253 break; 254 case CHECK_SCRIPT: 255 check_script(host); 256 break; 257 default: 258 /* Any other TCP-style checks */ 259 host->last_up = host->up; 260 host->cte.host = host; 261 host->cte.table = table; 262 bcopy(&tv, &host->cte.tv_start, 263 sizeof(host->cte.tv_start)); 264 check_tcp(&host->cte); 265 break; 266 } 267 } 268 } 269 check_icmp(env, &tv); 270 271 bcopy(&env->sc_interval, &tv, sizeof(tv)); 272 evtimer_add(&env->sc_ev, &tv); 273 } 274 275 void 276 hce_notify_done(struct host *host, enum host_error he) 277 { 278 struct table *table; 279 struct ctl_status st; 280 struct timeval tv_now, tv_dur; 281 u_long duration; 282 u_int logopt; 283 struct host *h; 284 int hostup; 285 const char *msg; 286 287 hostup = host->up; 288 host->he = he; 289 290 if (host->up == HOST_DOWN && host->retry_cnt) { 291 log_debug("hce_notify_done: host %s retry %d", 292 host->conf.name, host->retry_cnt); 293 host->up = host->last_up; 294 host->retry_cnt--; 295 } else 296 host->retry_cnt = host->conf.retry; 297 if (host->up != HOST_UNKNOWN) { 298 host->check_cnt++; 299 if (host->up == HOST_UP) 300 host->up_cnt++; 301 } 302 st.id = host->conf.id; 303 st.up = host->up; 304 st.check_cnt = host->check_cnt; 305 st.retry_cnt = host->retry_cnt; 306 st.he = he; 307 host->flags |= (F_CHECK_SENT|F_CHECK_DONE); 308 msg = host_error(he); 309 if (msg) 310 log_debug("hce_notify_done: %s (%s)", host->conf.name, msg); 311 312 imsg_compose_event(iev_pfe, IMSG_HOST_STATUS, 313 0, 0, -1, &st, sizeof(st)); 314 if (host->up != host->last_up) 315 logopt = RELAYD_OPT_LOGUPDATE; 316 else 317 logopt = RELAYD_OPT_LOGNOTIFY; 318 319 if (gettimeofday(&tv_now, NULL) == -1) 320 fatal("hce_notify_done: gettimeofday"); 321 timersub(&tv_now, &host->cte.tv_start, &tv_dur); 322 if (timercmp(&host->cte.tv_start, &tv_dur, >)) 323 duration = (tv_dur.tv_sec * 1000) + (tv_dur.tv_usec / 1000.0); 324 else 325 duration = 0; 326 327 if ((table = table_find(env, host->conf.tableid)) == NULL) 328 fatalx("hce_notify_done: invalid table id"); 329 330 if (env->sc_opts & logopt) { 331 log_info("host %s, check %s%s (%lums), state %s -> %s, " 332 "availability %s", 333 host->conf.name, table_check(table->conf.check), 334 (table->conf.flags & F_SSL) ? " use ssl" : "", duration, 335 host_status(host->last_up), host_status(host->up), 336 print_availability(host->check_cnt, host->up_cnt)); 337 } 338 339 if (host->last_up != host->up) 340 snmp_hosttrap(table, host); 341 342 host->last_up = host->up; 343 344 if (SLIST_EMPTY(&host->children)) 345 return; 346 347 /* Notify for all other hosts that inherit the state from this one */ 348 SLIST_FOREACH(h, &host->children, child) { 349 h->up = hostup; 350 hce_notify_done(h, he); 351 } 352 } 353 354 void 355 hce_shutdown(void) 356 { 357 log_info("host check engine exiting"); 358 _exit(0); 359 } 360 361 void 362 hce_dispatch_imsg(int fd, short event, void *ptr) 363 { 364 struct imsgev *iev; 365 struct imsgbuf *ibuf; 366 struct imsg imsg; 367 ssize_t n; 368 objid_t id; 369 struct host *host; 370 struct table *table; 371 372 iev = ptr; 373 ibuf = &iev->ibuf; 374 375 if (event & EV_READ) { 376 if ((n = imsg_read(ibuf)) == -1) 377 fatal("hce_dispatch_imsg: imsg_read_error"); 378 if (n == 0) { 379 /* this pipe is dead, so remove the event handler */ 380 event_del(&iev->ev); 381 event_loopexit(NULL); 382 return; 383 } 384 } 385 386 if (event & EV_WRITE) { 387 if (msgbuf_write(&ibuf->w) == -1) 388 fatal("hce_dispatch_imsg: msgbuf_write"); 389 } 390 391 for (;;) { 392 if ((n = imsg_get(ibuf, &imsg)) == -1) 393 fatal("hce_dispatch_imsg: imsg_read error"); 394 if (n == 0) 395 break; 396 397 switch (imsg.hdr.type) { 398 case IMSG_HOST_DISABLE: 399 memcpy(&id, imsg.data, sizeof(id)); 400 if ((host = host_find(env, id)) == NULL) 401 fatalx("hce_dispatch_imsg: desynchronized"); 402 host->flags |= F_DISABLE; 403 host->up = HOST_UNKNOWN; 404 host->check_cnt = 0; 405 host->up_cnt = 0; 406 host->he = HCE_NONE; 407 break; 408 case IMSG_HOST_ENABLE: 409 memcpy(&id, imsg.data, sizeof(id)); 410 if ((host = host_find(env, id)) == NULL) 411 fatalx("hce_dispatch_imsg: desynchronized"); 412 host->flags &= ~(F_DISABLE); 413 host->up = HOST_UNKNOWN; 414 host->he = HCE_NONE; 415 break; 416 case IMSG_TABLE_DISABLE: 417 memcpy(&id, imsg.data, sizeof(id)); 418 if ((table = table_find(env, id)) == NULL) 419 fatalx("hce_dispatch_imsg: desynchronized"); 420 table->conf.flags |= F_DISABLE; 421 TAILQ_FOREACH(host, &table->hosts, entry) 422 host->up = HOST_UNKNOWN; 423 break; 424 case IMSG_TABLE_ENABLE: 425 memcpy(&id, imsg.data, sizeof(id)); 426 if ((table = table_find(env, id)) == NULL) 427 fatalx("hce_dispatch_imsg: desynchronized"); 428 table->conf.flags &= ~(F_DISABLE); 429 TAILQ_FOREACH(host, &table->hosts, entry) 430 host->up = HOST_UNKNOWN; 431 break; 432 case IMSG_CTL_POLL: 433 evtimer_del(&env->sc_ev); 434 TAILQ_FOREACH(table, env->sc_tables, entry) 435 table->skipped = 0; 436 hce_launch_checks(-1, EV_TIMEOUT, env); 437 break; 438 default: 439 log_debug("hce_dispatch_msg: unexpected imsg %d", 440 imsg.hdr.type); 441 break; 442 } 443 imsg_free(&imsg); 444 } 445 imsg_event_add(iev); 446 } 447 448 void 449 hce_dispatch_parent(int fd, short event, void * ptr) 450 { 451 struct imsgev *iev; 452 struct imsgbuf *ibuf; 453 struct imsg imsg; 454 struct ctl_script scr; 455 ssize_t n; 456 size_t len; 457 static struct table *table = NULL; 458 struct host *host, *parent; 459 460 iev = ptr; 461 ibuf = &iev->ibuf; 462 463 if (event & EV_READ) { 464 if ((n = imsg_read(ibuf)) == -1) 465 fatal("hce_dispatch_parent: imsg_read error"); 466 if (n == 0) { 467 /* this pipe is dead, so remove the event handler */ 468 event_del(&iev->ev); 469 event_loopexit(NULL); 470 return; 471 } 472 } 473 474 if (event & EV_WRITE) { 475 if (msgbuf_write(&ibuf->w) == -1) 476 fatal("hce_dispatch_parent: msgbuf_write"); 477 } 478 479 for (;;) { 480 if ((n = imsg_get(ibuf, &imsg)) == -1) 481 fatal("hce_dispatch_parent: imsg_read error"); 482 if (n == 0) 483 break; 484 485 switch (imsg.hdr.type) { 486 case IMSG_SCRIPT: 487 if (imsg.hdr.len - IMSG_HEADER_SIZE != 488 sizeof(scr)) 489 fatalx("hce_dispatch_parent: " 490 "invalid size of script request"); 491 bcopy(imsg.data, &scr, sizeof(scr)); 492 script_done(env, &scr); 493 break; 494 case IMSG_RECONF: 495 log_debug("hce: reloading configuration"); 496 if (imsg.hdr.len != 497 sizeof(struct relayd) + IMSG_HEADER_SIZE) 498 fatalx("corrupted reload data"); 499 hce_disable_events(); 500 purge_config(env, PURGE_TABLES); 501 merge_config(env, (struct relayd *)imsg.data); 502 503 env->sc_tables = calloc(1, sizeof(*env->sc_tables)); 504 if (env->sc_tables == NULL) 505 fatal(NULL); 506 507 TAILQ_INIT(env->sc_tables); 508 break; 509 case IMSG_RECONF_TABLE: 510 if ((table = calloc(1, sizeof(*table))) == NULL) 511 fatal(NULL); 512 memcpy(&table->conf, imsg.data, sizeof(table->conf)); 513 TAILQ_INIT(&table->hosts); 514 TAILQ_INSERT_TAIL(env->sc_tables, table, entry); 515 break; 516 case IMSG_RECONF_SENDBUF: 517 len = imsg.hdr.len - IMSG_HEADER_SIZE; 518 table->sendbuf = calloc(1, len); 519 (void)strlcpy(table->sendbuf, (char *)imsg.data, len); 520 break; 521 case IMSG_RECONF_HOST: 522 if ((host = calloc(1, sizeof(*host))) == NULL) 523 fatal(NULL); 524 memcpy(&host->conf, imsg.data, sizeof(host->conf)); 525 host->tablename = table->conf.name; 526 TAILQ_INSERT_TAIL(&table->hosts, host, entry); 527 if (host->conf.parentid) { 528 parent = host_find(env, host->conf.parentid); 529 SLIST_INSERT_HEAD(&parent->children, 530 host, child); 531 } 532 break; 533 case IMSG_RECONF_END: 534 log_warnx("hce: configuration reloaded"); 535 hce_setup_events(); 536 break; 537 default: 538 log_debug("hce_dispatch_parent: unexpected imsg %d", 539 imsg.hdr.type); 540 break; 541 } 542 imsg_free(&imsg); 543 } 544 imsg_event_add(iev); 545 } 546