1 /* $OpenBSD: control.c,v 1.43 2012/04/19 14:48:44 deraadt 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/queue.h> 20 #include <sys/param.h> 21 #include <sys/stat.h> 22 #include <sys/socket.h> 23 #include <sys/un.h> 24 25 #include <net/if.h> 26 27 #include <errno.h> 28 #include <event.h> 29 #include <fcntl.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 #include <signal.h> 34 35 #include <openssl/ssl.h> 36 37 #include "relayd.h" 38 39 #define CONTROL_BACKLOG 5 40 41 struct ctl_connlist ctl_conns; 42 43 void control_accept(int, short, void *); 44 void control_close(int, struct control_sock *); 45 46 int 47 control_init(struct privsep *ps, struct control_sock *cs) 48 { 49 struct relayd *env = ps->ps_env; 50 struct sockaddr_un sun; 51 int fd; 52 mode_t old_umask, mode; 53 54 if (cs->cs_name == NULL) 55 return (0); 56 57 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) { 58 log_warn("%s: socket", __func__); 59 return (-1); 60 } 61 62 sun.sun_family = AF_UNIX; 63 if (strlcpy(sun.sun_path, cs->cs_name, 64 sizeof(sun.sun_path)) >= sizeof(sun.sun_path)) { 65 log_warn("%s: %s name too long", __func__, cs->cs_name); 66 close(fd); 67 return (-1); 68 } 69 70 if (unlink(cs->cs_name) == -1) 71 if (errno != ENOENT) { 72 log_warn("%s: unlink %s", __func__, cs->cs_name); 73 close(fd); 74 return (-1); 75 } 76 77 if (cs->cs_restricted) { 78 old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH); 79 mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH; 80 } else { 81 old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH); 82 mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP; 83 } 84 85 if (bind(fd, (struct sockaddr *)&sun, sizeof(sun)) == -1) { 86 log_warn("%s: bind: %s", __func__, cs->cs_name); 87 close(fd); 88 (void)umask(old_umask); 89 return (-1); 90 } 91 (void)umask(old_umask); 92 93 if (chmod(cs->cs_name, mode) == -1) { 94 log_warn("%s: chmod", __func__); 95 close(fd); 96 (void)unlink(cs->cs_name); 97 return (-1); 98 } 99 100 socket_set_blockmode(fd, BM_NONBLOCK); 101 cs->cs_fd = fd; 102 cs->cs_env = env; 103 104 return (0); 105 } 106 107 int 108 control_listen(struct control_sock *cs) 109 { 110 if (cs->cs_name == NULL) 111 return (0); 112 113 if (listen(cs->cs_fd, CONTROL_BACKLOG) == -1) { 114 log_warn("%s: listen", __func__); 115 return (-1); 116 } 117 118 event_set(&cs->cs_ev, cs->cs_fd, EV_READ, 119 control_accept, cs); 120 event_add(&cs->cs_ev, NULL); 121 evtimer_set(&cs->cs_evt, control_accept, cs); 122 123 return (0); 124 } 125 126 void 127 control_cleanup(struct control_sock *cs) 128 { 129 if (cs->cs_name == NULL) 130 return; 131 event_del(&cs->cs_ev); 132 event_del(&cs->cs_evt); 133 (void)unlink(cs->cs_name); 134 } 135 136 /* ARGSUSED */ 137 void 138 control_accept(int listenfd, short event, void *arg) 139 { 140 int connfd; 141 socklen_t len; 142 struct sockaddr_un sun; 143 struct ctl_conn *c; 144 struct control_sock *cs = arg; 145 146 event_add(&cs->cs_ev, NULL); 147 if ((event & EV_TIMEOUT)) 148 return; 149 150 len = sizeof(sun); 151 if ((connfd = accept(listenfd, 152 (struct sockaddr *)&sun, &len)) == -1) { 153 /* 154 * Pause accept if we are out of file descriptors, or 155 * libevent will haunt us here too. 156 */ 157 if (errno == ENFILE || errno == EMFILE) { 158 struct timeval evtpause = { 1, 0 }; 159 160 event_del(&cs->cs_ev); 161 evtimer_add(&cs->cs_evt, &evtpause); 162 } else if (errno != EWOULDBLOCK && errno != EINTR) 163 log_warn("%s: accept", __func__); 164 return; 165 } 166 167 socket_set_blockmode(connfd, BM_NONBLOCK); 168 169 if ((c = calloc(1, sizeof(struct ctl_conn))) == NULL) { 170 close(connfd); 171 log_warn("%s: calloc", __func__); 172 return; 173 } 174 175 imsg_init(&c->iev.ibuf, connfd); 176 c->iev.handler = control_dispatch_imsg; 177 c->iev.events = EV_READ; 178 c->iev.data = cs; /* proc.c cheats (reuses the handler) */ 179 event_set(&c->iev.ev, c->iev.ibuf.fd, c->iev.events, 180 c->iev.handler, cs); 181 event_add(&c->iev.ev, NULL); 182 183 TAILQ_INSERT_TAIL(&ctl_conns, c, entry); 184 } 185 186 struct ctl_conn * 187 control_connbyfd(int fd) 188 { 189 struct ctl_conn *c; 190 191 for (c = TAILQ_FIRST(&ctl_conns); c != NULL && c->iev.ibuf.fd != fd; 192 c = TAILQ_NEXT(c, entry)) 193 ; /* nothing */ 194 195 return (c); 196 } 197 198 void 199 control_close(int fd, struct control_sock *cs) 200 { 201 struct ctl_conn *c; 202 203 if ((c = control_connbyfd(fd)) == NULL) { 204 log_warn("%s: fd %d not found", __func__, fd); 205 return; 206 } 207 208 msgbuf_clear(&c->iev.ibuf.w); 209 TAILQ_REMOVE(&ctl_conns, c, entry); 210 211 event_del(&c->iev.ev); 212 close(c->iev.ibuf.fd); 213 214 /* Some file descriptors are available again. */ 215 if (evtimer_pending(&cs->cs_evt, NULL)) { 216 evtimer_del(&cs->cs_evt); 217 event_add(&cs->cs_ev, NULL); 218 } 219 220 free(c); 221 } 222 223 /* ARGSUSED */ 224 void 225 control_dispatch_imsg(int fd, short event, void *arg) 226 { 227 struct control_sock *cs = arg; 228 struct ctl_conn *c; 229 struct imsg imsg; 230 struct ctl_id id; 231 int n; 232 int verbose; 233 struct relayd *env = cs->cs_env; 234 235 if ((c = control_connbyfd(fd)) == NULL) { 236 log_warn("%s: fd %d not found", __func__, fd); 237 return; 238 } 239 240 if (event & EV_READ) { 241 if ((n = imsg_read(&c->iev.ibuf)) == -1 || n == 0) { 242 control_close(fd, cs); 243 return; 244 } 245 } 246 247 if (event & EV_WRITE) { 248 if (msgbuf_write(&c->iev.ibuf.w) < 0) { 249 control_close(fd, cs); 250 return; 251 } 252 } 253 254 for (;;) { 255 if ((n = imsg_get(&c->iev.ibuf, &imsg)) == -1) { 256 control_close(fd, cs); 257 return; 258 } 259 260 if (n == 0) 261 break; 262 263 if (c->waiting) { 264 log_debug("%s: unexpected imsg %d", 265 __func__, imsg.hdr.type); 266 imsg_free(&imsg); 267 control_close(fd, cs); 268 return; 269 } 270 271 switch (imsg.hdr.type) { 272 case IMSG_CTL_SHOW_SUM: 273 show(c); 274 break; 275 case IMSG_CTL_SESSION: 276 show_sessions(c); 277 break; 278 case IMSG_CTL_RDR_DISABLE: 279 if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(id)) 280 fatalx("invalid imsg header len"); 281 memcpy(&id, imsg.data, sizeof(id)); 282 if (disable_rdr(c, &id)) 283 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 284 0, 0, -1, NULL, 0); 285 else { 286 memcpy(imsg.data, &id, sizeof(id)); 287 control_imsg_forward(&imsg); 288 imsg_compose_event(&c->iev, IMSG_CTL_OK, 289 0, 0, -1, NULL, 0); 290 } 291 break; 292 case IMSG_CTL_RDR_ENABLE: 293 if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(id)) 294 fatalx("invalid imsg header len"); 295 memcpy(&id, imsg.data, sizeof(id)); 296 if (enable_rdr(c, &id)) 297 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 298 0, 0, -1, NULL, 0); 299 else { 300 memcpy(imsg.data, &id, sizeof(id)); 301 control_imsg_forward(&imsg); 302 imsg_compose_event(&c->iev, IMSG_CTL_OK, 303 0, 0, -1, NULL, 0); 304 } 305 break; 306 case IMSG_CTL_TABLE_DISABLE: 307 if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(id)) 308 fatalx("invalid imsg header len"); 309 memcpy(&id, imsg.data, sizeof(id)); 310 if (disable_table(c, &id)) 311 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 312 0, 0, -1, NULL, 0); 313 else { 314 memcpy(imsg.data, &id, sizeof(id)); 315 control_imsg_forward(&imsg); 316 imsg_compose_event(&c->iev, IMSG_CTL_OK, 317 0, 0, -1, NULL, 0); 318 } 319 break; 320 case IMSG_CTL_TABLE_ENABLE: 321 if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(id)) 322 fatalx("invalid imsg header len"); 323 memcpy(&id, imsg.data, sizeof(id)); 324 if (enable_table(c, &id)) 325 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 326 0, 0, -1, NULL, 0); 327 else { 328 memcpy(imsg.data, &id, sizeof(id)); 329 control_imsg_forward(&imsg); 330 imsg_compose_event(&c->iev, IMSG_CTL_OK, 331 0, 0, -1, NULL, 0); 332 } 333 break; 334 case IMSG_CTL_HOST_DISABLE: 335 if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(id)) 336 fatalx("invalid imsg header len"); 337 memcpy(&id, imsg.data, sizeof(id)); 338 if (disable_host(c, &id, NULL)) 339 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 340 0, 0, -1, NULL, 0); 341 else { 342 memcpy(imsg.data, &id, sizeof(id)); 343 control_imsg_forward(&imsg); 344 imsg_compose_event(&c->iev, IMSG_CTL_OK, 345 0, 0, -1, NULL, 0); 346 } 347 break; 348 case IMSG_CTL_HOST_ENABLE: 349 if (imsg.hdr.len != IMSG_HEADER_SIZE + sizeof(id)) 350 fatalx("invalid imsg header len"); 351 memcpy(&id, imsg.data, sizeof(id)); 352 if (enable_host(c, &id, NULL)) 353 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 354 0, 0, -1, NULL, 0); 355 else { 356 memcpy(imsg.data, &id, sizeof(id)); 357 control_imsg_forward(&imsg); 358 imsg_compose_event(&c->iev, IMSG_CTL_OK, 359 0, 0, -1, NULL, 0); 360 } 361 break; 362 case IMSG_CTL_SHUTDOWN: 363 case IMSG_CTL_RELOAD: 364 proc_forward_imsg(env->sc_ps, &imsg, PROC_PARENT, -1); 365 break; 366 case IMSG_CTL_POLL: 367 proc_compose_imsg(env->sc_ps, PROC_HCE, -1, 368 IMSG_CTL_POLL, -1, NULL, 0); 369 imsg_compose_event(&c->iev, IMSG_CTL_OK, 370 0, 0, -1, NULL, 0); 371 break; 372 case IMSG_CTL_NOTIFY: 373 if (c->flags & CTL_CONN_NOTIFY) { 374 log_debug("%s: " 375 "client requested notify more than once", 376 __func__); 377 imsg_compose_event(&c->iev, IMSG_CTL_FAIL, 378 0, 0, -1, NULL, 0); 379 break; 380 } 381 c->flags |= CTL_CONN_NOTIFY; 382 break; 383 case IMSG_CTL_VERBOSE: 384 IMSG_SIZE_CHECK(&imsg, &verbose); 385 386 memcpy(&verbose, imsg.data, sizeof(verbose)); 387 388 proc_forward_imsg(env->sc_ps, &imsg, PROC_PARENT, -1); 389 proc_forward_imsg(env->sc_ps, &imsg, PROC_HCE, -1); 390 proc_forward_imsg(env->sc_ps, &imsg, PROC_RELAY, -1); 391 392 memcpy(imsg.data, &verbose, sizeof(verbose)); 393 control_imsg_forward(&imsg); 394 log_verbose(verbose); 395 break; 396 default: 397 log_debug("%s: error handling imsg %d", 398 __func__, imsg.hdr.type); 399 break; 400 } 401 imsg_free(&imsg); 402 } 403 404 imsg_event_add(&c->iev); 405 } 406 407 void 408 control_imsg_forward(struct imsg *imsg) 409 { 410 struct ctl_conn *c; 411 412 TAILQ_FOREACH(c, &ctl_conns, entry) 413 if (c->flags & CTL_CONN_NOTIFY) 414 imsg_compose_event(&c->iev, imsg->hdr.type, 415 0, imsg->hdr.pid, -1, imsg->data, 416 imsg->hdr.len - IMSG_HEADER_SIZE); 417 } 418 419 void 420 socket_set_blockmode(int fd, enum blockmodes bm) 421 { 422 int flags; 423 424 if ((flags = fcntl(fd, F_GETFL, 0)) == -1) 425 fatal("fcntl F_GETFL"); 426 427 if (bm == BM_NONBLOCK) 428 flags |= O_NONBLOCK; 429 else 430 flags &= ~O_NONBLOCK; 431 432 if ((flags = fcntl(fd, F_SETFL, flags)) == -1) 433 fatal("fcntl F_SETFL"); 434 } 435