1 /* $OpenBSD: client.c,v 1.161 2023/07/10 12:00:08 nicm Exp $ */ 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 25 #include <errno.h> 26 #include <event.h> 27 #include <fcntl.h> 28 #include <imsg.h> 29 #include <signal.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <unistd.h> 33 34 #include "tmux.h" 35 36 static struct tmuxproc *client_proc; 37 static struct tmuxpeer *client_peer; 38 static uint64_t client_flags; 39 static int client_suspended; 40 static enum { 41 CLIENT_EXIT_NONE, 42 CLIENT_EXIT_DETACHED, 43 CLIENT_EXIT_DETACHED_HUP, 44 CLIENT_EXIT_LOST_TTY, 45 CLIENT_EXIT_TERMINATED, 46 CLIENT_EXIT_LOST_SERVER, 47 CLIENT_EXIT_EXITED, 48 CLIENT_EXIT_SERVER_EXITED, 49 CLIENT_EXIT_MESSAGE_PROVIDED 50 } client_exitreason = CLIENT_EXIT_NONE; 51 static int client_exitflag; 52 static int client_exitval; 53 static enum msgtype client_exittype; 54 static const char *client_exitsession; 55 static char *client_exitmessage; 56 static const char *client_execshell; 57 static const char *client_execcmd; 58 static int client_attached; 59 static struct client_files client_files = RB_INITIALIZER(&client_files); 60 61 static __dead void client_exec(const char *,const char *); 62 static int client_get_lock(char *); 63 static int client_connect(struct event_base *, const char *, 64 uint64_t); 65 static void client_send_identify(const char *, const char *, 66 char **, u_int, const char *, int); 67 static void client_signal(int); 68 static void client_dispatch(struct imsg *, void *); 69 static void client_dispatch_attached(struct imsg *); 70 static void client_dispatch_wait(struct imsg *); 71 static const char *client_exit_message(void); 72 73 /* 74 * Get server create lock. If already held then server start is happening in 75 * another client, so block until the lock is released and return -2 to 76 * retry. Return -1 on failure to continue and start the server anyway. 77 */ 78 static int 79 client_get_lock(char *lockfile) 80 { 81 int lockfd; 82 83 log_debug("lock file is %s", lockfile); 84 85 if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1) { 86 log_debug("open failed: %s", strerror(errno)); 87 return (-1); 88 } 89 90 if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) { 91 log_debug("flock failed: %s", strerror(errno)); 92 if (errno != EAGAIN) 93 return (lockfd); 94 while (flock(lockfd, LOCK_EX) == -1 && errno == EINTR) 95 /* nothing */; 96 close(lockfd); 97 return (-2); 98 } 99 log_debug("flock succeeded"); 100 101 return (lockfd); 102 } 103 104 /* Connect client to server. */ 105 static int 106 client_connect(struct event_base *base, const char *path, uint64_t flags) 107 { 108 struct sockaddr_un sa; 109 size_t size; 110 int fd, lockfd = -1, locked = 0; 111 char *lockfile = NULL; 112 113 memset(&sa, 0, sizeof sa); 114 sa.sun_family = AF_UNIX; 115 size = strlcpy(sa.sun_path, path, sizeof sa.sun_path); 116 if (size >= sizeof sa.sun_path) { 117 errno = ENAMETOOLONG; 118 return (-1); 119 } 120 log_debug("socket is %s", path); 121 122 retry: 123 if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1) 124 return (-1); 125 126 log_debug("trying connect"); 127 if (connect(fd, (struct sockaddr *)&sa, sizeof sa) == -1) { 128 log_debug("connect failed: %s", strerror(errno)); 129 if (errno != ECONNREFUSED && errno != ENOENT) 130 goto failed; 131 if (flags & CLIENT_NOSTARTSERVER) 132 goto failed; 133 if (~flags & CLIENT_STARTSERVER) 134 goto failed; 135 close(fd); 136 137 if (!locked) { 138 xasprintf(&lockfile, "%s.lock", path); 139 if ((lockfd = client_get_lock(lockfile)) < 0) { 140 log_debug("didn't get lock (%d)", lockfd); 141 142 free(lockfile); 143 lockfile = NULL; 144 145 if (lockfd == -2) 146 goto retry; 147 } 148 log_debug("got lock (%d)", lockfd); 149 150 /* 151 * Always retry at least once, even if we got the lock, 152 * because another client could have taken the lock, 153 * started the server and released the lock between our 154 * connect() and flock(). 155 */ 156 locked = 1; 157 goto retry; 158 } 159 160 if (lockfd >= 0 && unlink(path) != 0 && errno != ENOENT) { 161 free(lockfile); 162 close(lockfd); 163 return (-1); 164 } 165 fd = server_start(client_proc, flags, base, lockfd, lockfile); 166 } 167 168 if (locked && lockfd >= 0) { 169 free(lockfile); 170 close(lockfd); 171 } 172 setblocking(fd, 0); 173 return (fd); 174 175 failed: 176 if (locked) { 177 free(lockfile); 178 close(lockfd); 179 } 180 close(fd); 181 return (-1); 182 } 183 184 /* Get exit string from reason number. */ 185 const char * 186 client_exit_message(void) 187 { 188 static char msg[256]; 189 190 switch (client_exitreason) { 191 case CLIENT_EXIT_NONE: 192 break; 193 case CLIENT_EXIT_DETACHED: 194 if (client_exitsession != NULL) { 195 xsnprintf(msg, sizeof msg, "detached " 196 "(from session %s)", client_exitsession); 197 return (msg); 198 } 199 return ("detached"); 200 case CLIENT_EXIT_DETACHED_HUP: 201 if (client_exitsession != NULL) { 202 xsnprintf(msg, sizeof msg, "detached and SIGHUP " 203 "(from session %s)", client_exitsession); 204 return (msg); 205 } 206 return ("detached and SIGHUP"); 207 case CLIENT_EXIT_LOST_TTY: 208 return ("lost tty"); 209 case CLIENT_EXIT_TERMINATED: 210 return ("terminated"); 211 case CLIENT_EXIT_LOST_SERVER: 212 return ("server exited unexpectedly"); 213 case CLIENT_EXIT_EXITED: 214 return ("exited"); 215 case CLIENT_EXIT_SERVER_EXITED: 216 return ("server exited"); 217 case CLIENT_EXIT_MESSAGE_PROVIDED: 218 return (client_exitmessage); 219 } 220 return ("unknown reason"); 221 } 222 223 /* Exit if all streams flushed. */ 224 static void 225 client_exit(void) 226 { 227 if (!file_write_left(&client_files)) 228 proc_exit(client_proc); 229 } 230 231 /* Client main loop. */ 232 int 233 client_main(struct event_base *base, int argc, char **argv, uint64_t flags, 234 int feat) 235 { 236 struct cmd_parse_result *pr; 237 struct msg_command *data; 238 int fd, i; 239 const char *ttynam, *termname, *cwd; 240 pid_t ppid; 241 enum msgtype msg; 242 struct termios tio, saved_tio; 243 size_t size, linesize = 0; 244 ssize_t linelen; 245 char *line = NULL, **caps = NULL, *cause; 246 u_int ncaps = 0; 247 struct args_value *values; 248 249 /* Set up the initial command. */ 250 if (shell_command != NULL) { 251 msg = MSG_SHELL; 252 flags |= CLIENT_STARTSERVER; 253 } else if (argc == 0) { 254 msg = MSG_COMMAND; 255 flags |= CLIENT_STARTSERVER; 256 } else { 257 msg = MSG_COMMAND; 258 259 /* 260 * It's annoying parsing the command string twice (in client 261 * and later in server) but it is necessary to get the start 262 * server flag. 263 */ 264 values = args_from_vector(argc, argv); 265 pr = cmd_parse_from_arguments(values, argc, 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 args_free_values(values, argc); 273 free(values); 274 } 275 276 /* Create client process structure (starts logging). */ 277 client_proc = proc_start("client"); 278 proc_set_signals(client_proc, client_signal); 279 280 /* Save the flags. */ 281 client_flags = flags; 282 log_debug("flags are %#llx", (unsigned long long)client_flags); 283 284 /* Initialize the client socket and start the server. */ 285 fd = client_connect(base, socket_path, client_flags); 286 if (fd == -1) { 287 if (errno == ECONNREFUSED) { 288 fprintf(stderr, "no server running on %s\n", 289 socket_path); 290 } else { 291 fprintf(stderr, "error connecting to %s (%s)\n", 292 socket_path, strerror(errno)); 293 } 294 return (1); 295 } 296 client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL); 297 298 /* Save these before pledge(). */ 299 if ((cwd = find_cwd()) == NULL && (cwd = find_home()) == NULL) 300 cwd = "/"; 301 if ((ttynam = ttyname(STDIN_FILENO)) == NULL) 302 ttynam = ""; 303 if ((termname = getenv("TERM")) == NULL) 304 termname = ""; 305 306 /* 307 * Drop privileges for client. "proc exec" is needed for -c and for 308 * locking (which uses system(3)). 309 * 310 * "tty" is needed to restore termios(4) and also for some reason -CC 311 * does not work properly without it (input is not recognised). 312 * 313 * "sendfd" is dropped later in client_dispatch_wait(). 314 */ 315 if (pledge( 316 "stdio rpath wpath cpath unix sendfd proc exec tty", 317 NULL) != 0) 318 fatal("pledge failed"); 319 320 /* Load terminfo entry if any. */ 321 if (isatty(STDIN_FILENO) && 322 *termname != '\0' && 323 tty_term_read_list(termname, STDIN_FILENO, &caps, &ncaps, 324 &cause) != 0) { 325 fprintf(stderr, "%s\n", cause); 326 free(cause); 327 return (1); 328 } 329 330 /* Free stuff that is not used in the client. */ 331 if (ptm_fd != -1) 332 close(ptm_fd); 333 options_free(global_options); 334 options_free(global_s_options); 335 options_free(global_w_options); 336 environ_free(global_environ); 337 338 /* Set up control mode. */ 339 if (client_flags & CLIENT_CONTROLCONTROL) { 340 if (tcgetattr(STDIN_FILENO, &saved_tio) != 0) { 341 fprintf(stderr, "tcgetattr failed: %s\n", 342 strerror(errno)); 343 return (1); 344 } 345 cfmakeraw(&tio); 346 tio.c_iflag = ICRNL|IXANY; 347 tio.c_oflag = OPOST|ONLCR; 348 tio.c_lflag = NOKERNINFO; 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 proc_flush_peer(client_peer); 361 362 /* Send first command. */ 363 if (msg == MSG_COMMAND) { 364 /* How big is the command? */ 365 size = 0; 366 for (i = 0; i < argc; i++) 367 size += strlen(argv[i]) + 1; 368 if (size > MAX_IMSGSIZE - (sizeof *data)) { 369 fprintf(stderr, "command too long\n"); 370 return (1); 371 } 372 data = xmalloc((sizeof *data) + size); 373 374 /* Prepare command for server. */ 375 data->argc = argc; 376 if (cmd_pack_argv(argc, argv, (char *)(data + 1), size) != 0) { 377 fprintf(stderr, "command too long\n"); 378 free(data); 379 return (1); 380 } 381 size += sizeof *data; 382 383 /* Send the command. */ 384 if (proc_send(client_peer, msg, -1, data, size) != 0) { 385 fprintf(stderr, "failed to send command\n"); 386 free(data); 387 return (1); 388 } 389 free(data); 390 } else if (msg == MSG_SHELL) 391 proc_send(client_peer, msg, -1, NULL, 0); 392 393 /* Start main loop. */ 394 proc_loop(client_proc, NULL); 395 396 /* Run command if user requested exec, instead of exiting. */ 397 if (client_exittype == MSG_EXEC) { 398 if (client_flags & CLIENT_CONTROLCONTROL) 399 tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio); 400 client_exec(client_execshell, client_execcmd); 401 } 402 403 /* Restore streams to blocking. */ 404 setblocking(STDIN_FILENO, 1); 405 setblocking(STDOUT_FILENO, 1); 406 setblocking(STDERR_FILENO, 1); 407 408 /* Print the exit message, if any, and exit. */ 409 if (client_attached) { 410 if (client_exitreason != CLIENT_EXIT_NONE) 411 printf("[%s]\n", client_exit_message()); 412 413 ppid = getppid(); 414 if (client_exittype == MSG_DETACHKILL && ppid > 1) 415 kill(ppid, SIGHUP); 416 } else if (client_flags & CLIENT_CONTROL) { 417 if (client_exitreason != CLIENT_EXIT_NONE) 418 printf("%%exit %s\n", client_exit_message()); 419 else 420 printf("%%exit\n"); 421 fflush(stdout); 422 if (client_flags & CLIENT_CONTROL_WAITEXIT) { 423 setvbuf(stdin, NULL, _IOLBF, 0); 424 for (;;) { 425 linelen = getline(&line, &linesize, stdin); 426 if (linelen <= 1) 427 break; 428 } 429 free(line); 430 } 431 if (client_flags & CLIENT_CONTROLCONTROL) { 432 printf("\033\\"); 433 fflush(stdout); 434 tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio); 435 } 436 } else if (client_exitreason != CLIENT_EXIT_NONE) 437 fprintf(stderr, "%s\n", client_exit_message()); 438 return (client_exitval); 439 } 440 441 /* Send identify messages to server. */ 442 static void 443 client_send_identify(const char *ttynam, const char *termname, char **caps, 444 u_int ncaps, const char *cwd, int feat) 445 { 446 char **ss; 447 size_t sslen; 448 int fd, flags = client_flags; 449 pid_t pid; 450 u_int i; 451 452 proc_send(client_peer, MSG_IDENTIFY_FLAGS, -1, &flags, sizeof flags); 453 proc_send(client_peer, MSG_IDENTIFY_LONGFLAGS, -1, &client_flags, 454 sizeof client_flags); 455 456 proc_send(client_peer, MSG_IDENTIFY_TERM, -1, termname, 457 strlen(termname) + 1); 458 proc_send(client_peer, MSG_IDENTIFY_FEATURES, -1, &feat, sizeof feat); 459 460 proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam, 461 strlen(ttynam) + 1); 462 proc_send(client_peer, MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1); 463 464 for (i = 0; i < ncaps; i++) { 465 proc_send(client_peer, MSG_IDENTIFY_TERMINFO, -1, 466 caps[i], strlen(caps[i]) + 1); 467 } 468 469 if ((fd = dup(STDIN_FILENO)) == -1) 470 fatal("dup failed"); 471 proc_send(client_peer, MSG_IDENTIFY_STDIN, fd, NULL, 0); 472 if ((fd = dup(STDOUT_FILENO)) == -1) 473 fatal("dup failed"); 474 proc_send(client_peer, MSG_IDENTIFY_STDOUT, fd, NULL, 0); 475 476 pid = getpid(); 477 proc_send(client_peer, MSG_IDENTIFY_CLIENTPID, -1, &pid, sizeof pid); 478 479 for (ss = environ; *ss != NULL; ss++) { 480 sslen = strlen(*ss) + 1; 481 if (sslen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) 482 continue; 483 proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen); 484 } 485 486 proc_send(client_peer, MSG_IDENTIFY_DONE, -1, NULL, 0); 487 } 488 489 /* Run command in shell; used for -c. */ 490 static __dead void 491 client_exec(const char *shell, const char *shellcmd) 492 { 493 const char *name, *ptr; 494 char *argv0; 495 496 log_debug("shell %s, command %s", shell, shellcmd); 497 498 ptr = strrchr(shell, '/'); 499 if (ptr != NULL && *(ptr + 1) != '\0') 500 name = ptr + 1; 501 else 502 name = shell; 503 if (client_flags & CLIENT_LOGIN) 504 xasprintf(&argv0, "-%s", name); 505 else 506 xasprintf(&argv0, "%s", name); 507 setenv("SHELL", shell, 1); 508 509 proc_clear_signals(client_proc, 1); 510 511 setblocking(STDIN_FILENO, 1); 512 setblocking(STDOUT_FILENO, 1); 513 setblocking(STDERR_FILENO, 1); 514 closefrom(STDERR_FILENO + 1); 515 516 execl(shell, argv0, "-c", shellcmd, (char *) NULL); 517 fatal("execl failed"); 518 } 519 520 /* Callback to handle signals in the client. */ 521 static void 522 client_signal(int sig) 523 { 524 struct sigaction sigact; 525 int status; 526 pid_t pid; 527 528 log_debug("%s: %s", __func__, strsignal(sig)); 529 if (sig == SIGCHLD) { 530 for (;;) { 531 pid = waitpid(WAIT_ANY, &status, WNOHANG); 532 if (pid == 0) 533 break; 534 if (pid == -1) { 535 if (errno == ECHILD) 536 break; 537 log_debug("waitpid failed: %s", 538 strerror(errno)); 539 } 540 } 541 } else if (!client_attached) { 542 if (sig == SIGTERM || sig == SIGHUP) 543 proc_exit(client_proc); 544 } else { 545 switch (sig) { 546 case SIGHUP: 547 client_exitreason = CLIENT_EXIT_LOST_TTY; 548 client_exitval = 1; 549 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 550 break; 551 case SIGTERM: 552 if (!client_suspended) 553 client_exitreason = CLIENT_EXIT_TERMINATED; 554 client_exitval = 1; 555 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 556 break; 557 case SIGWINCH: 558 proc_send(client_peer, MSG_RESIZE, -1, NULL, 0); 559 break; 560 case SIGCONT: 561 memset(&sigact, 0, sizeof sigact); 562 sigemptyset(&sigact.sa_mask); 563 sigact.sa_flags = SA_RESTART; 564 sigact.sa_handler = SIG_IGN; 565 if (sigaction(SIGTSTP, &sigact, NULL) != 0) 566 fatal("sigaction failed"); 567 proc_send(client_peer, MSG_WAKEUP, -1, NULL, 0); 568 client_suspended = 0; 569 break; 570 } 571 } 572 } 573 574 /* Callback for file write error or close. */ 575 static void 576 client_file_check_cb(__unused struct client *c, __unused const char *path, 577 __unused int error, __unused int closed, __unused struct evbuffer *buffer, 578 __unused void *data) 579 { 580 if (client_exitflag) 581 client_exit(); 582 } 583 584 /* Callback for client read events. */ 585 static void 586 client_dispatch(struct imsg *imsg, __unused void *arg) 587 { 588 if (imsg == NULL) { 589 if (!client_exitflag) { 590 client_exitreason = CLIENT_EXIT_LOST_SERVER; 591 client_exitval = 1; 592 } 593 proc_exit(client_proc); 594 return; 595 } 596 597 if (client_attached) 598 client_dispatch_attached(imsg); 599 else 600 client_dispatch_wait(imsg); 601 } 602 603 /* Process an exit message. */ 604 static void 605 client_dispatch_exit_message(char *data, size_t datalen) 606 { 607 int retval; 608 609 if (datalen < sizeof retval && datalen != 0) 610 fatalx("bad MSG_EXIT size"); 611 612 if (datalen >= sizeof retval) { 613 memcpy(&retval, data, sizeof retval); 614 client_exitval = retval; 615 } 616 617 if (datalen > sizeof retval) { 618 datalen -= sizeof retval; 619 data += sizeof retval; 620 621 client_exitmessage = xmalloc(datalen); 622 memcpy(client_exitmessage, data, datalen); 623 client_exitmessage[datalen - 1] = '\0'; 624 625 client_exitreason = CLIENT_EXIT_MESSAGE_PROVIDED; 626 } 627 } 628 629 /* Dispatch imsgs when in wait state (before MSG_READY). */ 630 static void 631 client_dispatch_wait(struct imsg *imsg) 632 { 633 char *data; 634 ssize_t datalen; 635 static int pledge_applied; 636 637 /* 638 * "sendfd" is no longer required once all of the identify messages 639 * have been sent. We know the server won't send us anything until that 640 * point (because we don't ask it to), so we can drop "sendfd" once we 641 * get the first message from the server. 642 */ 643 if (!pledge_applied) { 644 if (pledge( 645 "stdio rpath wpath cpath unix proc exec tty", 646 NULL) != 0) 647 fatal("pledge failed"); 648 pledge_applied = 1; 649 } 650 651 data = imsg->data; 652 datalen = imsg->hdr.len - IMSG_HEADER_SIZE; 653 654 switch (imsg->hdr.type) { 655 case MSG_EXIT: 656 case MSG_SHUTDOWN: 657 client_dispatch_exit_message(data, datalen); 658 client_exitflag = 1; 659 client_exit(); 660 break; 661 case MSG_READY: 662 if (datalen != 0) 663 fatalx("bad MSG_READY size"); 664 665 client_attached = 1; 666 proc_send(client_peer, MSG_RESIZE, -1, NULL, 0); 667 break; 668 case MSG_VERSION: 669 if (datalen != 0) 670 fatalx("bad MSG_VERSION size"); 671 672 fprintf(stderr, "protocol version mismatch " 673 "(client %d, server %u)\n", PROTOCOL_VERSION, 674 imsg->hdr.peerid & 0xff); 675 client_exitval = 1; 676 proc_exit(client_proc); 677 break; 678 case MSG_FLAGS: 679 if (datalen != sizeof client_flags) 680 fatalx("bad MSG_FLAGS string"); 681 682 memcpy(&client_flags, data, sizeof client_flags); 683 log_debug("new flags are %#llx", 684 (unsigned long long)client_flags); 685 break; 686 case MSG_SHELL: 687 if (datalen == 0 || data[datalen - 1] != '\0') 688 fatalx("bad MSG_SHELL string"); 689 690 client_exec(data, shell_command); 691 /* NOTREACHED */ 692 case MSG_DETACH: 693 case MSG_DETACHKILL: 694 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 695 break; 696 case MSG_EXITED: 697 proc_exit(client_proc); 698 break; 699 case MSG_READ_OPEN: 700 file_read_open(&client_files, client_peer, imsg, 1, 701 !(client_flags & CLIENT_CONTROL), client_file_check_cb, 702 NULL); 703 break; 704 case MSG_READ_CANCEL: 705 file_read_cancel(&client_files, imsg); 706 break; 707 case MSG_WRITE_OPEN: 708 file_write_open(&client_files, client_peer, imsg, 1, 709 !(client_flags & CLIENT_CONTROL), client_file_check_cb, 710 NULL); 711 break; 712 case MSG_WRITE: 713 file_write_data(&client_files, imsg); 714 break; 715 case MSG_WRITE_CLOSE: 716 file_write_close(&client_files, imsg); 717 break; 718 case MSG_OLDSTDERR: 719 case MSG_OLDSTDIN: 720 case MSG_OLDSTDOUT: 721 fprintf(stderr, "server version is too old for client\n"); 722 proc_exit(client_proc); 723 break; 724 } 725 } 726 727 /* Dispatch imsgs in attached state (after MSG_READY). */ 728 static void 729 client_dispatch_attached(struct imsg *imsg) 730 { 731 struct sigaction sigact; 732 char *data; 733 ssize_t datalen; 734 735 data = imsg->data; 736 datalen = imsg->hdr.len - IMSG_HEADER_SIZE; 737 738 switch (imsg->hdr.type) { 739 case MSG_FLAGS: 740 if (datalen != sizeof client_flags) 741 fatalx("bad MSG_FLAGS string"); 742 743 memcpy(&client_flags, data, sizeof client_flags); 744 log_debug("new flags are %#llx", 745 (unsigned long long)client_flags); 746 break; 747 case MSG_DETACH: 748 case MSG_DETACHKILL: 749 if (datalen == 0 || data[datalen - 1] != '\0') 750 fatalx("bad MSG_DETACH string"); 751 752 client_exitsession = xstrdup(data); 753 client_exittype = imsg->hdr.type; 754 if (imsg->hdr.type == MSG_DETACHKILL) 755 client_exitreason = CLIENT_EXIT_DETACHED_HUP; 756 else 757 client_exitreason = CLIENT_EXIT_DETACHED; 758 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 759 break; 760 case MSG_EXEC: 761 if (datalen == 0 || data[datalen - 1] != '\0' || 762 strlen(data) + 1 == (size_t)datalen) 763 fatalx("bad MSG_EXEC string"); 764 client_execcmd = xstrdup(data); 765 client_execshell = xstrdup(data + strlen(data) + 1); 766 767 client_exittype = imsg->hdr.type; 768 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 769 break; 770 case MSG_EXIT: 771 client_dispatch_exit_message(data, datalen); 772 if (client_exitreason == CLIENT_EXIT_NONE) 773 client_exitreason = CLIENT_EXIT_EXITED; 774 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 775 break; 776 case MSG_EXITED: 777 if (datalen != 0) 778 fatalx("bad MSG_EXITED size"); 779 780 proc_exit(client_proc); 781 break; 782 case MSG_SHUTDOWN: 783 if (datalen != 0) 784 fatalx("bad MSG_SHUTDOWN size"); 785 786 proc_send(client_peer, MSG_EXITING, -1, NULL, 0); 787 client_exitreason = CLIENT_EXIT_SERVER_EXITED; 788 client_exitval = 1; 789 break; 790 case MSG_SUSPEND: 791 if (datalen != 0) 792 fatalx("bad MSG_SUSPEND size"); 793 794 memset(&sigact, 0, sizeof sigact); 795 sigemptyset(&sigact.sa_mask); 796 sigact.sa_flags = SA_RESTART; 797 sigact.sa_handler = SIG_DFL; 798 if (sigaction(SIGTSTP, &sigact, NULL) != 0) 799 fatal("sigaction failed"); 800 client_suspended = 1; 801 kill(getpid(), SIGTSTP); 802 break; 803 case MSG_LOCK: 804 if (datalen == 0 || data[datalen - 1] != '\0') 805 fatalx("bad MSG_LOCK string"); 806 807 system(data); 808 proc_send(client_peer, MSG_UNLOCK, -1, NULL, 0); 809 break; 810 } 811 } 812