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 struct args_value *values; 247 248 /* Ignore SIGCHLD now or daemon() in the server will leave a zombie. */ 249 signal(SIGCHLD, SIG_IGN); 250 251 /* Set up the initial command. */ 252 if (shell_command != NULL) { 253 msg = MSG_SHELL; 254 flags |= CLIENT_STARTSERVER; 255 } else if (argc == 0) { 256 msg = MSG_COMMAND; 257 flags |= CLIENT_STARTSERVER; 258 } else { 259 msg = MSG_COMMAND; 260 261 /* 262 * It's annoying parsing the command string twice (in client 263 * and later in server) but it is necessary to get the start 264 * server flag. 265 */ 266 values = args_from_vector(argc, argv); 267 pr = cmd_parse_from_arguments(values, argc, NULL); 268 if (pr->status == CMD_PARSE_SUCCESS) { 269 if (cmd_list_any_have(pr->cmdlist, CMD_STARTSERVER)) 270 flags |= CLIENT_STARTSERVER; 271 cmd_list_free(pr->cmdlist); 272 } else 273 free(pr->error); 274 args_free_values(values, argc); 275 free(values); 276 } 277 278 /* Create client process structure (starts logging). */ 279 client_proc = proc_start("client"); 280 proc_set_signals(client_proc, client_signal); 281 282 /* Save the flags. */ 283 client_flags = flags; 284 log_debug("flags are %#llx", (unsigned long long)client_flags); 285 286 /* Initialize the client socket and start the server. */ 287 fd = client_connect(base, socket_path, client_flags); 288 if (fd == -1) { 289 if (errno == ECONNREFUSED) { 290 fprintf(stderr, "no server running on %s\n", 291 socket_path); 292 } else { 293 fprintf(stderr, "error connecting to %s (%s)\n", 294 socket_path, strerror(errno)); 295 } 296 return (1); 297 } 298 client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL); 299 300 /* Save these before pledge(). */ 301 if ((cwd = find_cwd()) == NULL && (cwd = find_home()) == NULL) 302 cwd = "/"; 303 if ((ttynam = ttyname(STDIN_FILENO)) == NULL) 304 ttynam = ""; 305 if ((termname = getenv("TERM")) == NULL) 306 termname = ""; 307 308 /* 309 * Drop privileges for client. "proc exec" is needed for -c and for 310 * locking (which uses system(3)). 311 * 312 * "tty" is needed to restore termios(4) and also for some reason -CC 313 * does not work properly without it (input is not recognised). 314 * 315 * "sendfd" is dropped later in client_dispatch_wait(). 316 */ 317 if (pledge( 318 "stdio rpath wpath cpath unix sendfd proc exec tty", 319 NULL) != 0) 320 fatal("pledge failed"); 321 322 /* Load terminfo entry if any. */ 323 if (isatty(STDIN_FILENO) && 324 *termname != '\0' && 325 tty_term_read_list(termname, STDIN_FILENO, &caps, &ncaps, 326 &cause) != 0) { 327 fprintf(stderr, "%s\n", cause); 328 free(cause); 329 return (1); 330 } 331 332 /* Free stuff that is not used in the client. */ 333 if (ptm_fd != -1) 334 close(ptm_fd); 335 options_free(global_options); 336 options_free(global_s_options); 337 options_free(global_w_options); 338 environ_free(global_environ); 339 340 /* Set up control mode. */ 341 if (client_flags & CLIENT_CONTROLCONTROL) { 342 if (tcgetattr(STDIN_FILENO, &saved_tio) != 0) { 343 fprintf(stderr, "tcgetattr failed: %s\n", 344 strerror(errno)); 345 return (1); 346 } 347 cfmakeraw(&tio); 348 tio.c_iflag = ICRNL|IXANY; 349 tio.c_oflag = OPOST|ONLCR; 350 #ifdef NOKERNINFO 351 tio.c_lflag = NOKERNINFO; 352 #endif 353 tio.c_cflag = CREAD|CS8|HUPCL; 354 tio.c_cc[VMIN] = 1; 355 tio.c_cc[VTIME] = 0; 356 cfsetispeed(&tio, cfgetispeed(&saved_tio)); 357 cfsetospeed(&tio, cfgetospeed(&saved_tio)); 358 tcsetattr(STDIN_FILENO, TCSANOW, &tio); 359 } 360 361 /* Send identify messages. */ 362 client_send_identify(ttynam, termname, caps, ncaps, cwd, feat); 363 tty_term_free_list(caps, ncaps); 364 proc_flush_peer(client_peer); 365 366 /* Send first command. */ 367 if (msg == MSG_COMMAND) { 368 /* How big is the command? */ 369 size = 0; 370 for (i = 0; i < argc; i++) 371 size += strlen(argv[i]) + 1; 372 if (size > MAX_IMSGSIZE - (sizeof *data)) { 373 fprintf(stderr, "command too long\n"); 374 return (1); 375 } 376 data = xmalloc((sizeof *data) + size); 377 378 /* Prepare command for server. */ 379 data->argc = argc; 380 if (cmd_pack_argv(argc, argv, (char *)(data + 1), size) != 0) { 381 fprintf(stderr, "command too long\n"); 382 free(data); 383 return (1); 384 } 385 size += sizeof *data; 386 387 /* Send the command. */ 388 if (proc_send(client_peer, msg, -1, data, size) != 0) { 389 fprintf(stderr, "failed to send command\n"); 390 free(data); 391 return (1); 392 } 393 free(data); 394 } else if (msg == MSG_SHELL) 395 proc_send(client_peer, msg, -1, NULL, 0); 396 397 /* Start main loop. */ 398 proc_loop(client_proc, NULL); 399 400 /* Run command if user requested exec, instead of exiting. */ 401 if (client_exittype == MSG_EXEC) { 402 if (client_flags & CLIENT_CONTROLCONTROL) 403 tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio); 404 client_exec(client_execshell, client_execcmd); 405 } 406 407 /* Restore streams to blocking. */ 408 setblocking(STDIN_FILENO, 1); 409 setblocking(STDOUT_FILENO, 1); 410 setblocking(STDERR_FILENO, 1); 411 412 /* Print the exit message, if any, and exit. */ 413 if (client_attached) { 414 if (client_exitreason != CLIENT_EXIT_NONE) 415 printf("[%s]\n", client_exit_message()); 416 417 ppid = getppid(); 418 if (client_exittype == MSG_DETACHKILL && ppid > 1) 419 kill(ppid, SIGHUP); 420 } else if (client_flags & CLIENT_CONTROL) { 421 if (client_exitreason != CLIENT_EXIT_NONE) 422 printf("%%exit %s\n", client_exit_message()); 423 else 424 printf("%%exit\n"); 425 fflush(stdout); 426 if (client_flags & CLIENT_CONTROL_WAITEXIT) { 427 setvbuf(stdin, NULL, _IOLBF, 0); 428 for (;;) { 429 linelen = getline(&line, &linesize, stdin); 430 if (linelen <= 1) 431 break; 432 } 433 free(line); 434 } 435 if (client_flags & CLIENT_CONTROLCONTROL) { 436 printf("\033\\"); 437 fflush(stdout); 438 tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio); 439 } 440 } else if (client_exitreason != CLIENT_EXIT_NONE) 441 fprintf(stderr, "%s\n", client_exit_message()); 442 return (client_exitval); 443 } 444 445 /* Send identify messages to server. */ 446 static void 447 client_send_identify(const char *ttynam, const char *termname, char **caps, 448 u_int ncaps, const char *cwd, int feat) 449 { 450 char **ss; 451 size_t sslen; 452 int fd, flags = client_flags; 453 pid_t pid; 454 u_int i; 455 456 proc_send(client_peer, MSG_IDENTIFY_FLAGS, -1, &flags, sizeof flags); 457 proc_send(client_peer, MSG_IDENTIFY_LONGFLAGS, -1, &client_flags, 458 sizeof client_flags); 459 460 proc_send(client_peer, MSG_IDENTIFY_TERM, -1, termname, 461 strlen(termname) + 1); 462 proc_send(client_peer, MSG_IDENTIFY_FEATURES, -1, &feat, sizeof feat); 463 464 proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam, 465 strlen(ttynam) + 1); 466 proc_send(client_peer, MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1); 467 468 for (i = 0; i < ncaps; i++) { 469 proc_send(client_peer, MSG_IDENTIFY_TERMINFO, -1, 470 caps[i], strlen(caps[i]) + 1); 471 } 472 473 if ((fd = dup(STDIN_FILENO)) == -1) 474 fatal("dup failed"); 475 proc_send(client_peer, MSG_IDENTIFY_STDIN, fd, NULL, 0); 476 if ((fd = dup(STDOUT_FILENO)) == -1) 477 fatal("dup failed"); 478 proc_send(client_peer, MSG_IDENTIFY_STDOUT, fd, NULL, 0); 479 480 pid = getpid(); 481 proc_send(client_peer, MSG_IDENTIFY_CLIENTPID, -1, &pid, sizeof pid); 482 483 for (ss = environ; *ss != NULL; ss++) { 484 sslen = strlen(*ss) + 1; 485 if (sslen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) 486 continue; 487 proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen); 488 } 489 490 proc_send(client_peer, MSG_IDENTIFY_DONE, -1, NULL, 0); 491 } 492 493 /* Run command in shell; used for -c. */ 494 static __dead void 495 client_exec(const char *shell, const char *shellcmd) 496 { 497 const char *name, *ptr; 498 char *argv0; 499 500 log_debug("shell %s, command %s", shell, shellcmd); 501 502 ptr = strrchr(shell, '/'); 503 if (ptr != NULL && *(ptr + 1) != '\0') 504 name = ptr + 1; 505 else 506 name = shell; 507 if (client_flags & CLIENT_LOGIN) 508 xasprintf(&argv0, "-%s", name); 509 else 510 xasprintf(&argv0, "%s", name); 511 setenv("SHELL", shell, 1); 512 513 proc_clear_signals(client_proc, 1); 514 515 setblocking(STDIN_FILENO, 1); 516 setblocking(STDOUT_FILENO, 1); 517 setblocking(STDERR_FILENO, 1); 518 closefrom(STDERR_FILENO + 1); 519 520 execl(shell, argv0, "-c", shellcmd, (char *) NULL); 521 fatal("execl failed"); 522 } 523 524 /* Callback to handle signals in the client. */ 525 static void 526 client_signal(int sig) 527 { 528 struct sigaction sigact; 529 int status; 530 531 log_debug("%s: %s", __func__, strsignal(sig)); 532 if (sig == SIGCHLD) 533 waitpid(WAIT_ANY, &status, WNOHANG); 534 else if (!client_attached) { 535 if (sig == SIGTERM || sig == SIGHUP) 536 proc_exit(client_proc); 537 } else { 538 switch (sig) { 539 case SIGHUP: 540 client_exitreason = CLIENT_EXIT_LOST_TTY; 541 client_exitval = 1; 542 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 543 break; 544 case SIGTERM: 545 if (!client_suspended) 546 client_exitreason = CLIENT_EXIT_TERMINATED; 547 client_exitval = 1; 548 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 549 break; 550 case SIGWINCH: 551 proc_send(client_peer, MSG_RESIZE, -1, NULL, 0); 552 break; 553 case SIGCONT: 554 memset(&sigact, 0, sizeof sigact); 555 sigemptyset(&sigact.sa_mask); 556 sigact.sa_flags = SA_RESTART; 557 sigact.sa_handler = SIG_IGN; 558 if (sigaction(SIGTSTP, &sigact, NULL) != 0) 559 fatal("sigaction failed"); 560 proc_send(client_peer, MSG_WAKEUP, -1, NULL, 0); 561 client_suspended = 0; 562 break; 563 } 564 } 565 } 566 567 /* Callback for file write error or close. */ 568 static void 569 client_file_check_cb(__unused struct client *c, __unused const char *path, 570 __unused int error, __unused int closed, __unused struct evbuffer *buffer, 571 __unused void *data) 572 { 573 if (client_exitflag) 574 client_exit(); 575 } 576 577 /* Callback for client read events. */ 578 static void 579 client_dispatch(struct imsg *imsg, __unused void *arg) 580 { 581 if (imsg == NULL) { 582 if (!client_exitflag) { 583 client_exitreason = CLIENT_EXIT_LOST_SERVER; 584 client_exitval = 1; 585 } 586 proc_exit(client_proc); 587 return; 588 } 589 590 if (client_attached) 591 client_dispatch_attached(imsg); 592 else 593 client_dispatch_wait(imsg); 594 } 595 596 /* Process an exit message. */ 597 static void 598 client_dispatch_exit_message(char *data, size_t datalen) 599 { 600 int retval; 601 602 if (datalen < sizeof retval && datalen != 0) 603 fatalx("bad MSG_EXIT size"); 604 605 if (datalen >= sizeof retval) { 606 memcpy(&retval, data, sizeof retval); 607 client_exitval = retval; 608 } 609 610 if (datalen > sizeof retval) { 611 datalen -= sizeof retval; 612 data += sizeof retval; 613 614 client_exitmessage = xmalloc(datalen); 615 memcpy(client_exitmessage, data, datalen); 616 client_exitmessage[datalen - 1] = '\0'; 617 618 client_exitreason = CLIENT_EXIT_MESSAGE_PROVIDED; 619 } 620 } 621 622 /* Dispatch imsgs when in wait state (before MSG_READY). */ 623 static void 624 client_dispatch_wait(struct imsg *imsg) 625 { 626 char *data; 627 ssize_t datalen; 628 static int pledge_applied; 629 630 /* 631 * "sendfd" is no longer required once all of the identify messages 632 * have been sent. We know the server won't send us anything until that 633 * point (because we don't ask it to), so we can drop "sendfd" once we 634 * get the first message from the server. 635 */ 636 if (!pledge_applied) { 637 if (pledge( 638 "stdio rpath wpath cpath unix proc exec tty", 639 NULL) != 0) 640 fatal("pledge failed"); 641 pledge_applied = 1; 642 } 643 644 data = imsg->data; 645 datalen = imsg->hdr.len - IMSG_HEADER_SIZE; 646 647 switch (imsg->hdr.type) { 648 case MSG_EXIT: 649 case MSG_SHUTDOWN: 650 client_dispatch_exit_message(data, datalen); 651 client_exitflag = 1; 652 client_exit(); 653 break; 654 case MSG_READY: 655 if (datalen != 0) 656 fatalx("bad MSG_READY size"); 657 658 client_attached = 1; 659 proc_send(client_peer, MSG_RESIZE, -1, NULL, 0); 660 break; 661 case MSG_VERSION: 662 if (datalen != 0) 663 fatalx("bad MSG_VERSION size"); 664 665 fprintf(stderr, "protocol version mismatch " 666 "(client %d, server %u)\n", PROTOCOL_VERSION, 667 imsg->hdr.peerid & 0xff); 668 client_exitval = 1; 669 proc_exit(client_proc); 670 break; 671 case MSG_FLAGS: 672 if (datalen != sizeof client_flags) 673 fatalx("bad MSG_FLAGS string"); 674 675 memcpy(&client_flags, data, sizeof client_flags); 676 log_debug("new flags are %#llx", 677 (unsigned long long)client_flags); 678 break; 679 case MSG_SHELL: 680 if (datalen == 0 || data[datalen - 1] != '\0') 681 fatalx("bad MSG_SHELL string"); 682 683 client_exec(data, shell_command); 684 /* NOTREACHED */ 685 case MSG_DETACH: 686 case MSG_DETACHKILL: 687 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 688 break; 689 case MSG_EXITED: 690 proc_exit(client_proc); 691 break; 692 case MSG_READ_OPEN: 693 file_read_open(&client_files, client_peer, imsg, 1, 694 !(client_flags & CLIENT_CONTROL), client_file_check_cb, 695 NULL); 696 break; 697 case MSG_WRITE_OPEN: 698 file_write_open(&client_files, client_peer, imsg, 1, 699 !(client_flags & CLIENT_CONTROL), client_file_check_cb, 700 NULL); 701 break; 702 case MSG_WRITE: 703 file_write_data(&client_files, imsg); 704 break; 705 case MSG_WRITE_CLOSE: 706 file_write_close(&client_files, imsg); 707 break; 708 case MSG_OLDSTDERR: 709 case MSG_OLDSTDIN: 710 case MSG_OLDSTDOUT: 711 fprintf(stderr, "server version is too old for client\n"); 712 proc_exit(client_proc); 713 break; 714 } 715 } 716 717 /* Dispatch imsgs in attached state (after MSG_READY). */ 718 static void 719 client_dispatch_attached(struct imsg *imsg) 720 { 721 struct sigaction sigact; 722 char *data; 723 ssize_t datalen; 724 725 data = imsg->data; 726 datalen = imsg->hdr.len - IMSG_HEADER_SIZE; 727 728 switch (imsg->hdr.type) { 729 case MSG_FLAGS: 730 if (datalen != sizeof client_flags) 731 fatalx("bad MSG_FLAGS string"); 732 733 memcpy(&client_flags, data, sizeof client_flags); 734 log_debug("new flags are %#llx", 735 (unsigned long long)client_flags); 736 break; 737 case MSG_DETACH: 738 case MSG_DETACHKILL: 739 if (datalen == 0 || data[datalen - 1] != '\0') 740 fatalx("bad MSG_DETACH string"); 741 742 client_exitsession = xstrdup(data); 743 client_exittype = imsg->hdr.type; 744 if (imsg->hdr.type == MSG_DETACHKILL) 745 client_exitreason = CLIENT_EXIT_DETACHED_HUP; 746 else 747 client_exitreason = CLIENT_EXIT_DETACHED; 748 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 749 break; 750 case MSG_EXEC: 751 if (datalen == 0 || data[datalen - 1] != '\0' || 752 strlen(data) + 1 == (size_t)datalen) 753 fatalx("bad MSG_EXEC string"); 754 client_execcmd = xstrdup(data); 755 client_execshell = xstrdup(data + strlen(data) + 1); 756 757 client_exittype = imsg->hdr.type; 758 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 759 break; 760 case MSG_EXIT: 761 client_dispatch_exit_message(data, datalen); 762 if (client_exitreason == CLIENT_EXIT_NONE) 763 client_exitreason = CLIENT_EXIT_EXITED; 764 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 765 break; 766 case MSG_EXITED: 767 if (datalen != 0) 768 fatalx("bad MSG_EXITED size"); 769 770 proc_exit(client_proc); 771 break; 772 case MSG_SHUTDOWN: 773 if (datalen != 0) 774 fatalx("bad MSG_SHUTDOWN size"); 775 776 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 777 client_exitreason = CLIENT_EXIT_SERVER_EXITED; 778 client_exitval = 1; 779 break; 780 case MSG_SUSPEND: 781 if (datalen != 0) 782 fatalx("bad MSG_SUSPEND size"); 783 784 memset(&sigact, 0, sizeof sigact); 785 sigemptyset(&sigact.sa_mask); 786 sigact.sa_flags = SA_RESTART; 787 sigact.sa_handler = SIG_DFL; 788 if (sigaction(SIGTSTP, &sigact, NULL) != 0) 789 fatal("sigaction failed"); 790 client_suspended = 1; 791 kill(getpid(), SIGTSTP); 792 break; 793 case MSG_LOCK: 794 if (datalen == 0 || data[datalen - 1] != '\0') 795 fatalx("bad MSG_LOCK string"); 796 797 system(data); 798 proc_send(client_peer, MSG_UNLOCK, -1, NULL, 0); 799 break; 800 } 801 } 802