1 /* $OpenBSD$ */ 2 3 /* 4 * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com> 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 MIND, USE, DATA OR PROFITS, WHETHER 15 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING 16 * OUT OF 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/uio.h> 22 #include <sys/un.h> 23 #include <sys/wait.h> 24 #include <sys/file.h> 25 26 #include <errno.h> 27 #include <fcntl.h> 28 #include <signal.h> 29 #include <stdlib.h> 30 #include <string.h> 31 #include <unistd.h> 32 33 #include "tmux.h" 34 35 static struct tmuxproc *client_proc; 36 static struct tmuxpeer *client_peer; 37 static uint64_t client_flags; 38 static int client_suspended; 39 static enum { 40 CLIENT_EXIT_NONE, 41 CLIENT_EXIT_DETACHED, 42 CLIENT_EXIT_DETACHED_HUP, 43 CLIENT_EXIT_LOST_TTY, 44 CLIENT_EXIT_TERMINATED, 45 CLIENT_EXIT_LOST_SERVER, 46 CLIENT_EXIT_EXITED, 47 CLIENT_EXIT_SERVER_EXITED, 48 CLIENT_EXIT_MESSAGE_PROVIDED 49 } client_exitreason = CLIENT_EXIT_NONE; 50 static int client_exitflag; 51 static int client_exitval; 52 static enum msgtype client_exittype; 53 static const char *client_exitsession; 54 static char *client_exitmessage; 55 static const char *client_execshell; 56 static const char *client_execcmd; 57 static int client_attached; 58 static struct client_files client_files = RB_INITIALIZER(&client_files); 59 60 static __dead void client_exec(const char *,const char *); 61 static int client_get_lock(char *); 62 static int client_connect(struct event_base *, const char *, 63 uint64_t); 64 static void client_send_identify(const char *, const char *, 65 char **, u_int, const char *, int); 66 static void client_signal(int); 67 static void client_dispatch(struct imsg *, void *); 68 static void client_dispatch_attached(struct imsg *); 69 static void client_dispatch_wait(struct imsg *); 70 static const char *client_exit_message(void); 71 72 /* 73 * Get server create lock. If already held then server start is happening in 74 * another client, so block until the lock is released and return -2 to 75 * retry. Return -1 on failure to continue and start the server anyway. 76 */ 77 static int 78 client_get_lock(char *lockfile) 79 { 80 int lockfd; 81 82 log_debug("lock file is %s", lockfile); 83 84 if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1) { 85 log_debug("open failed: %s", strerror(errno)); 86 return (-1); 87 } 88 89 if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) { 90 log_debug("flock failed: %s", strerror(errno)); 91 if (errno != EAGAIN) 92 return (lockfd); 93 while (flock(lockfd, LOCK_EX) == -1 && errno == EINTR) 94 /* nothing */; 95 close(lockfd); 96 return (-2); 97 } 98 log_debug("flock succeeded"); 99 100 return (lockfd); 101 } 102 103 /* Connect client to server. */ 104 static int 105 client_connect(struct event_base *base, const char *path, uint64_t flags) 106 { 107 struct sockaddr_un sa; 108 size_t size; 109 int fd, lockfd = -1, locked = 0; 110 char *lockfile = NULL; 111 112 memset(&sa, 0, sizeof sa); 113 sa.sun_family = AF_UNIX; 114 size = strlcpy(sa.sun_path, path, sizeof sa.sun_path); 115 if (size >= sizeof sa.sun_path) { 116 errno = ENAMETOOLONG; 117 return (-1); 118 } 119 log_debug("socket is %s", path); 120 121 retry: 122 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) 123 return (-1); 124 125 log_debug("trying connect"); 126 if (connect(fd, (struct sockaddr *)&sa, sizeof sa) == -1) { 127 log_debug("connect failed: %s", strerror(errno)); 128 if (errno != ECONNREFUSED && errno != ENOENT) 129 goto failed; 130 if (flags & CLIENT_NOSTARTSERVER) 131 goto failed; 132 if (~flags & CLIENT_STARTSERVER) 133 goto failed; 134 close(fd); 135 136 if (!locked) { 137 xasprintf(&lockfile, "%s.lock", path); 138 if ((lockfd = client_get_lock(lockfile)) < 0) { 139 log_debug("didn't get lock (%d)", lockfd); 140 141 free(lockfile); 142 lockfile = NULL; 143 144 if (lockfd == -2) 145 goto retry; 146 } 147 log_debug("got lock (%d)", lockfd); 148 149 /* 150 * Always retry at least once, even if we got the lock, 151 * because another client could have taken the lock, 152 * started the server and released the lock between our 153 * connect() and flock(). 154 */ 155 locked = 1; 156 goto retry; 157 } 158 159 if (lockfd >= 0 && unlink(path) != 0 && errno != ENOENT) { 160 free(lockfile); 161 close(lockfd); 162 return (-1); 163 } 164 fd = server_start(client_proc, flags, base, lockfd, lockfile); 165 } 166 167 if (locked && lockfd >= 0) { 168 free(lockfile); 169 close(lockfd); 170 } 171 setblocking(fd, 0); 172 return (fd); 173 174 failed: 175 if (locked) { 176 free(lockfile); 177 close(lockfd); 178 } 179 close(fd); 180 return (-1); 181 } 182 183 /* Get exit string from reason number. */ 184 const char * 185 client_exit_message(void) 186 { 187 static char msg[256]; 188 189 switch (client_exitreason) { 190 case CLIENT_EXIT_NONE: 191 break; 192 case CLIENT_EXIT_DETACHED: 193 if (client_exitsession != NULL) { 194 xsnprintf(msg, sizeof msg, "detached " 195 "(from session %s)", client_exitsession); 196 return (msg); 197 } 198 return ("detached"); 199 case CLIENT_EXIT_DETACHED_HUP: 200 if (client_exitsession != NULL) { 201 xsnprintf(msg, sizeof msg, "detached and SIGHUP " 202 "(from session %s)", client_exitsession); 203 return (msg); 204 } 205 return ("detached and SIGHUP"); 206 case CLIENT_EXIT_LOST_TTY: 207 return ("lost tty"); 208 case CLIENT_EXIT_TERMINATED: 209 return ("terminated"); 210 case CLIENT_EXIT_LOST_SERVER: 211 return ("server exited unexpectedly"); 212 case CLIENT_EXIT_EXITED: 213 return ("exited"); 214 case CLIENT_EXIT_SERVER_EXITED: 215 return ("server exited"); 216 case CLIENT_EXIT_MESSAGE_PROVIDED: 217 return (client_exitmessage); 218 } 219 return ("unknown reason"); 220 } 221 222 /* Exit if all streams flushed. */ 223 static void 224 client_exit(void) 225 { 226 if (!file_write_left(&client_files)) 227 proc_exit(client_proc); 228 } 229 230 /* Client main loop. */ 231 int 232 client_main(struct event_base *base, int argc, char **argv, uint64_t flags, 233 int feat) 234 { 235 struct cmd_parse_result *pr; 236 struct msg_command *data; 237 int fd, i; 238 const char *ttynam, *termname, *cwd; 239 pid_t ppid; 240 enum msgtype msg; 241 struct termios tio, saved_tio; 242 size_t size, linesize = 0; 243 ssize_t linelen; 244 char *line = NULL, **caps = NULL, *cause; 245 u_int ncaps = 0; 246 247 /* Ignore SIGCHLD now or daemon() in the server will leave a zombie. */ 248 signal(SIGCHLD, SIG_IGN); 249 250 /* Set up the initial command. */ 251 if (shell_command != NULL) { 252 msg = MSG_SHELL; 253 flags |= CLIENT_STARTSERVER; 254 } else if (argc == 0) { 255 msg = MSG_COMMAND; 256 flags |= CLIENT_STARTSERVER; 257 } else { 258 msg = MSG_COMMAND; 259 260 /* 261 * It sucks parsing the command string twice (in client and 262 * later in server) but it is necessary to get the start server 263 * flag. 264 */ 265 pr = cmd_parse_from_arguments(argc, argv, NULL); 266 if (pr->status == CMD_PARSE_SUCCESS) { 267 if (cmd_list_any_have(pr->cmdlist, CMD_STARTSERVER)) 268 flags |= CLIENT_STARTSERVER; 269 cmd_list_free(pr->cmdlist); 270 } else 271 free(pr->error); 272 } 273 274 /* Create client process structure (starts logging). */ 275 client_proc = proc_start("client"); 276 proc_set_signals(client_proc, client_signal); 277 278 /* Save the flags. */ 279 client_flags = flags; 280 log_debug("flags are %#llx", (unsigned long long)client_flags); 281 282 /* Initialize the client socket and start the server. */ 283 fd = client_connect(base, socket_path, client_flags); 284 if (fd == -1) { 285 if (errno == ECONNREFUSED) { 286 fprintf(stderr, "no server running on %s\n", 287 socket_path); 288 } else { 289 fprintf(stderr, "error connecting to %s (%s)\n", 290 socket_path, strerror(errno)); 291 } 292 return (1); 293 } 294 client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL); 295 296 /* Save these before pledge(). */ 297 if ((cwd = find_cwd()) == NULL && (cwd = find_home()) == NULL) 298 cwd = "/"; 299 if ((ttynam = ttyname(STDIN_FILENO)) == NULL) 300 ttynam = ""; 301 if ((termname = getenv("TERM")) == NULL) 302 termname = ""; 303 304 /* 305 * Drop privileges for client. "proc exec" is needed for -c and for 306 * locking (which uses system(3)). 307 * 308 * "tty" is needed to restore termios(4) and also for some reason -CC 309 * does not work properly without it (input is not recognised). 310 * 311 * "sendfd" is dropped later in client_dispatch_wait(). 312 */ 313 if (pledge( 314 "stdio rpath wpath cpath unix sendfd proc exec tty", 315 NULL) != 0) 316 fatal("pledge failed"); 317 318 /* Load terminfo entry if any. */ 319 if (isatty(STDIN_FILENO) && 320 *termname != '\0' && 321 tty_term_read_list(termname, STDIN_FILENO, &caps, &ncaps, 322 &cause) != 0) { 323 fprintf(stderr, "%s\n", cause); 324 free(cause); 325 return (1); 326 } 327 328 /* Free stuff that is not used in the client. */ 329 if (ptm_fd != -1) 330 close(ptm_fd); 331 options_free(global_options); 332 options_free(global_s_options); 333 options_free(global_w_options); 334 environ_free(global_environ); 335 336 /* Set up control mode. */ 337 if (client_flags & CLIENT_CONTROLCONTROL) { 338 if (tcgetattr(STDIN_FILENO, &saved_tio) != 0) { 339 fprintf(stderr, "tcgetattr failed: %s\n", 340 strerror(errno)); 341 return (1); 342 } 343 cfmakeraw(&tio); 344 tio.c_iflag = ICRNL|IXANY; 345 tio.c_oflag = OPOST|ONLCR; 346 #ifdef NOKERNINFO 347 tio.c_lflag = NOKERNINFO; 348 #endif 349 tio.c_cflag = CREAD|CS8|HUPCL; 350 tio.c_cc[VMIN] = 1; 351 tio.c_cc[VTIME] = 0; 352 cfsetispeed(&tio, cfgetispeed(&saved_tio)); 353 cfsetospeed(&tio, cfgetospeed(&saved_tio)); 354 tcsetattr(STDIN_FILENO, TCSANOW, &tio); 355 } 356 357 /* Send identify messages. */ 358 client_send_identify(ttynam, termname, caps, ncaps, cwd, feat); 359 tty_term_free_list(caps, ncaps); 360 361 /* Send first command. */ 362 if (msg == MSG_COMMAND) { 363 /* How big is the command? */ 364 size = 0; 365 for (i = 0; i < argc; i++) 366 size += strlen(argv[i]) + 1; 367 if (size > MAX_IMSGSIZE - (sizeof *data)) { 368 fprintf(stderr, "command too long\n"); 369 return (1); 370 } 371 data = xmalloc((sizeof *data) + size); 372 373 /* Prepare command for server. */ 374 data->argc = argc; 375 if (cmd_pack_argv(argc, argv, (char *)(data + 1), size) != 0) { 376 fprintf(stderr, "command too long\n"); 377 free(data); 378 return (1); 379 } 380 size += sizeof *data; 381 382 /* Send the command. */ 383 if (proc_send(client_peer, msg, -1, data, size) != 0) { 384 fprintf(stderr, "failed to send command\n"); 385 free(data); 386 return (1); 387 } 388 free(data); 389 } else if (msg == MSG_SHELL) 390 proc_send(client_peer, msg, -1, NULL, 0); 391 392 /* Start main loop. */ 393 proc_loop(client_proc, NULL); 394 395 /* Run command if user requested exec, instead of exiting. */ 396 if (client_exittype == MSG_EXEC) { 397 if (client_flags & CLIENT_CONTROLCONTROL) 398 tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio); 399 client_exec(client_execshell, client_execcmd); 400 } 401 402 /* Restore streams to blocking. */ 403 setblocking(STDIN_FILENO, 1); 404 setblocking(STDOUT_FILENO, 1); 405 setblocking(STDERR_FILENO, 1); 406 407 /* Print the exit message, if any, and exit. */ 408 if (client_attached) { 409 if (client_exitreason != CLIENT_EXIT_NONE) 410 printf("[%s]\n", client_exit_message()); 411 412 ppid = getppid(); 413 if (client_exittype == MSG_DETACHKILL && ppid > 1) 414 kill(ppid, SIGHUP); 415 } else if (client_flags & CLIENT_CONTROL) { 416 if (client_exitreason != CLIENT_EXIT_NONE) 417 printf("%%exit %s\n", client_exit_message()); 418 else 419 printf("%%exit\n"); 420 fflush(stdout); 421 if (client_flags & CLIENT_CONTROL_WAITEXIT) { 422 setvbuf(stdin, NULL, _IOLBF, 0); 423 for (;;) { 424 linelen = getline(&line, &linesize, stdin); 425 if (linelen <= 1) 426 break; 427 } 428 free(line); 429 } 430 if (client_flags & CLIENT_CONTROLCONTROL) { 431 printf("\033\\"); 432 fflush(stdout); 433 tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio); 434 } 435 } else if (client_exitreason != CLIENT_EXIT_NONE) 436 fprintf(stderr, "%s\n", client_exit_message()); 437 return (client_exitval); 438 } 439 440 /* Send identify messages to server. */ 441 static void 442 client_send_identify(const char *ttynam, const char *termname, char **caps, 443 u_int ncaps, const char *cwd, int feat) 444 { 445 char **ss; 446 size_t sslen; 447 int fd, flags = client_flags; 448 pid_t pid; 449 u_int i; 450 451 proc_send(client_peer, MSG_IDENTIFY_FLAGS, -1, &flags, sizeof flags); 452 proc_send(client_peer, MSG_IDENTIFY_LONGFLAGS, -1, &client_flags, 453 sizeof client_flags); 454 455 proc_send(client_peer, MSG_IDENTIFY_TERM, -1, termname, 456 strlen(termname) + 1); 457 proc_send(client_peer, MSG_IDENTIFY_FEATURES, -1, &feat, sizeof feat); 458 459 proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam, 460 strlen(ttynam) + 1); 461 proc_send(client_peer, MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1); 462 463 for (i = 0; i < ncaps; i++) { 464 proc_send(client_peer, MSG_IDENTIFY_TERMINFO, -1, 465 caps[i], strlen(caps[i]) + 1); 466 } 467 468 if ((fd = dup(STDIN_FILENO)) == -1) 469 fatal("dup failed"); 470 proc_send(client_peer, MSG_IDENTIFY_STDIN, fd, NULL, 0); 471 if ((fd = dup(STDOUT_FILENO)) == -1) 472 fatal("dup failed"); 473 proc_send(client_peer, MSG_IDENTIFY_STDOUT, fd, NULL, 0); 474 475 pid = getpid(); 476 proc_send(client_peer, MSG_IDENTIFY_CLIENTPID, -1, &pid, sizeof pid); 477 478 for (ss = environ; *ss != NULL; ss++) { 479 sslen = strlen(*ss) + 1; 480 if (sslen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) 481 continue; 482 proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen); 483 } 484 485 proc_send(client_peer, MSG_IDENTIFY_DONE, -1, NULL, 0); 486 } 487 488 /* Run command in shell; used for -c. */ 489 static __dead void 490 client_exec(const char *shell, const char *shellcmd) 491 { 492 const char *name, *ptr; 493 char *argv0; 494 495 log_debug("shell %s, command %s", shell, shellcmd); 496 497 ptr = strrchr(shell, '/'); 498 if (ptr != NULL && *(ptr + 1) != '\0') 499 name = ptr + 1; 500 else 501 name = shell; 502 if (client_flags & CLIENT_LOGIN) 503 xasprintf(&argv0, "-%s", name); 504 else 505 xasprintf(&argv0, "%s", name); 506 setenv("SHELL", shell, 1); 507 508 proc_clear_signals(client_proc, 1); 509 510 setblocking(STDIN_FILENO, 1); 511 setblocking(STDOUT_FILENO, 1); 512 setblocking(STDERR_FILENO, 1); 513 closefrom(STDERR_FILENO + 1); 514 515 execl(shell, argv0, "-c", shellcmd, (char *) NULL); 516 fatal("execl failed"); 517 } 518 519 /* Callback to handle signals in the client. */ 520 static void 521 client_signal(int sig) 522 { 523 struct sigaction sigact; 524 int status; 525 526 log_debug("%s: %s", __func__, strsignal(sig)); 527 if (sig == SIGCHLD) 528 waitpid(WAIT_ANY, &status, WNOHANG); 529 else if (!client_attached) { 530 if (sig == SIGTERM) 531 proc_exit(client_proc); 532 } else { 533 switch (sig) { 534 case SIGHUP: 535 client_exitreason = CLIENT_EXIT_LOST_TTY; 536 client_exitval = 1; 537 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 538 break; 539 case SIGTERM: 540 if (!client_suspended) 541 client_exitreason = CLIENT_EXIT_TERMINATED; 542 client_exitval = 1; 543 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 544 break; 545 case SIGWINCH: 546 proc_send(client_peer, MSG_RESIZE, -1, NULL, 0); 547 break; 548 case SIGCONT: 549 memset(&sigact, 0, sizeof sigact); 550 sigemptyset(&sigact.sa_mask); 551 sigact.sa_flags = SA_RESTART; 552 sigact.sa_handler = SIG_IGN; 553 if (sigaction(SIGTSTP, &sigact, NULL) != 0) 554 fatal("sigaction failed"); 555 proc_send(client_peer, MSG_WAKEUP, -1, NULL, 0); 556 client_suspended = 0; 557 break; 558 } 559 } 560 } 561 562 /* Callback for file write error or close. */ 563 static void 564 client_file_check_cb(__unused struct client *c, __unused const char *path, 565 __unused int error, __unused int closed, __unused struct evbuffer *buffer, 566 __unused void *data) 567 { 568 if (client_exitflag) 569 client_exit(); 570 } 571 572 /* Callback for client read events. */ 573 static void 574 client_dispatch(struct imsg *imsg, __unused void *arg) 575 { 576 if (imsg == NULL) { 577 if (!client_exitflag) { 578 client_exitreason = CLIENT_EXIT_LOST_SERVER; 579 client_exitval = 1; 580 } 581 proc_exit(client_proc); 582 return; 583 } 584 585 if (client_attached) 586 client_dispatch_attached(imsg); 587 else 588 client_dispatch_wait(imsg); 589 } 590 591 /* Process an exit message. */ 592 static void 593 client_dispatch_exit_message(char *data, size_t datalen) 594 { 595 int retval; 596 597 if (datalen < sizeof retval && datalen != 0) 598 fatalx("bad MSG_EXIT size"); 599 600 if (datalen >= sizeof retval) { 601 memcpy(&retval, data, sizeof retval); 602 client_exitval = retval; 603 } 604 605 if (datalen > sizeof retval) { 606 datalen -= sizeof retval; 607 data += sizeof retval; 608 609 client_exitmessage = xmalloc(datalen); 610 memcpy(client_exitmessage, data, datalen); 611 client_exitmessage[datalen - 1] = '\0'; 612 613 client_exitreason = CLIENT_EXIT_MESSAGE_PROVIDED; 614 } 615 } 616 617 /* Dispatch imsgs when in wait state (before MSG_READY). */ 618 static void 619 client_dispatch_wait(struct imsg *imsg) 620 { 621 char *data; 622 ssize_t datalen; 623 static int pledge_applied; 624 625 /* 626 * "sendfd" is no longer required once all of the identify messages 627 * have been sent. We know the server won't send us anything until that 628 * point (because we don't ask it to), so we can drop "sendfd" once we 629 * get the first message from the server. 630 */ 631 if (!pledge_applied) { 632 if (pledge( 633 "stdio rpath wpath cpath unix proc exec tty", 634 NULL) != 0) 635 fatal("pledge failed"); 636 pledge_applied = 1; 637 } 638 639 data = imsg->data; 640 datalen = imsg->hdr.len - IMSG_HEADER_SIZE; 641 642 switch (imsg->hdr.type) { 643 case MSG_EXIT: 644 case MSG_SHUTDOWN: 645 client_dispatch_exit_message(data, datalen); 646 client_exitflag = 1; 647 client_exit(); 648 break; 649 case MSG_READY: 650 if (datalen != 0) 651 fatalx("bad MSG_READY size"); 652 653 client_attached = 1; 654 proc_send(client_peer, MSG_RESIZE, -1, NULL, 0); 655 break; 656 case MSG_VERSION: 657 if (datalen != 0) 658 fatalx("bad MSG_VERSION size"); 659 660 fprintf(stderr, "protocol version mismatch " 661 "(client %d, server %u)\n", PROTOCOL_VERSION, 662 imsg->hdr.peerid & 0xff); 663 client_exitval = 1; 664 proc_exit(client_proc); 665 break; 666 case MSG_FLAGS: 667 if (datalen != sizeof client_flags) 668 fatalx("bad MSG_FLAGS string"); 669 670 memcpy(&client_flags, data, sizeof client_flags); 671 log_debug("new flags are %#llx", 672 (unsigned long long)client_flags); 673 break; 674 case MSG_SHELL: 675 if (datalen == 0 || data[datalen - 1] != '\0') 676 fatalx("bad MSG_SHELL string"); 677 678 client_exec(data, shell_command); 679 /* NOTREACHED */ 680 case MSG_DETACH: 681 case MSG_DETACHKILL: 682 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 683 break; 684 case MSG_EXITED: 685 proc_exit(client_proc); 686 break; 687 case MSG_READ_OPEN: 688 file_read_open(&client_files, client_peer, imsg, 1, 689 !(client_flags & CLIENT_CONTROL), client_file_check_cb, 690 NULL); 691 break; 692 case MSG_WRITE_OPEN: 693 file_write_open(&client_files, client_peer, imsg, 1, 694 !(client_flags & CLIENT_CONTROL), client_file_check_cb, 695 NULL); 696 break; 697 case MSG_WRITE: 698 file_write_data(&client_files, imsg); 699 break; 700 case MSG_WRITE_CLOSE: 701 file_write_close(&client_files, imsg); 702 break; 703 case MSG_OLDSTDERR: 704 case MSG_OLDSTDIN: 705 case MSG_OLDSTDOUT: 706 fprintf(stderr, "server version is too old for client\n"); 707 proc_exit(client_proc); 708 break; 709 } 710 } 711 712 /* Dispatch imsgs in attached state (after MSG_READY). */ 713 static void 714 client_dispatch_attached(struct imsg *imsg) 715 { 716 struct sigaction sigact; 717 char *data; 718 ssize_t datalen; 719 720 data = imsg->data; 721 datalen = imsg->hdr.len - IMSG_HEADER_SIZE; 722 723 switch (imsg->hdr.type) { 724 case MSG_FLAGS: 725 if (datalen != sizeof client_flags) 726 fatalx("bad MSG_FLAGS string"); 727 728 memcpy(&client_flags, data, sizeof client_flags); 729 log_debug("new flags are %#llx", 730 (unsigned long long)client_flags); 731 break; 732 case MSG_DETACH: 733 case MSG_DETACHKILL: 734 if (datalen == 0 || data[datalen - 1] != '\0') 735 fatalx("bad MSG_DETACH string"); 736 737 client_exitsession = xstrdup(data); 738 client_exittype = imsg->hdr.type; 739 if (imsg->hdr.type == MSG_DETACHKILL) 740 client_exitreason = CLIENT_EXIT_DETACHED_HUP; 741 else 742 client_exitreason = CLIENT_EXIT_DETACHED; 743 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 744 break; 745 case MSG_EXEC: 746 if (datalen == 0 || data[datalen - 1] != '\0' || 747 strlen(data) + 1 == (size_t)datalen) 748 fatalx("bad MSG_EXEC string"); 749 client_execcmd = xstrdup(data); 750 client_execshell = xstrdup(data + strlen(data) + 1); 751 752 client_exittype = imsg->hdr.type; 753 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 754 break; 755 case MSG_EXIT: 756 client_dispatch_exit_message(data, datalen); 757 if (client_exitreason == CLIENT_EXIT_NONE) 758 client_exitreason = CLIENT_EXIT_EXITED; 759 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 760 break; 761 case MSG_EXITED: 762 if (datalen != 0) 763 fatalx("bad MSG_EXITED size"); 764 765 proc_exit(client_proc); 766 break; 767 case MSG_SHUTDOWN: 768 if (datalen != 0) 769 fatalx("bad MSG_SHUTDOWN size"); 770 771 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 772 client_exitreason = CLIENT_EXIT_SERVER_EXITED; 773 client_exitval = 1; 774 break; 775 case MSG_SUSPEND: 776 if (datalen != 0) 777 fatalx("bad MSG_SUSPEND size"); 778 779 memset(&sigact, 0, sizeof sigact); 780 sigemptyset(&sigact.sa_mask); 781 sigact.sa_flags = SA_RESTART; 782 sigact.sa_handler = SIG_DFL; 783 if (sigaction(SIGTSTP, &sigact, NULL) != 0) 784 fatal("sigaction failed"); 785 client_suspended = 1; 786 kill(getpid(), SIGTSTP); 787 break; 788 case MSG_LOCK: 789 if (datalen == 0 || data[datalen - 1] != '\0') 790 fatalx("bad MSG_LOCK string"); 791 792 system(data); 793 proc_send(client_peer, MSG_UNLOCK, -1, NULL, 0); 794 break; 795 } 796 } 797