Annotation of src/usr.bin/tmux/client.c, Revision 1.140
1.140 ! nicm 1: /* $OpenBSD: client.c,v 1.139 2020/03/30 15:49:23 nicm Exp $ */
1.1 nicm 2:
3: /*
1.113 nicm 4: * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
1.1 nicm 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/un.h>
22: #include <sys/wait.h>
23:
24: #include <errno.h>
1.30 nicm 25: #include <event.h>
1.80 nicm 26: #include <fcntl.h>
1.99 nicm 27: #include <imsg.h>
1.85 nicm 28: #include <signal.h>
1.1 nicm 29: #include <stdlib.h>
30: #include <string.h>
31: #include <unistd.h>
32:
33: #include "tmux.h"
34:
1.114 nicm 35: static struct tmuxproc *client_proc;
36: static struct tmuxpeer *client_peer;
37: static int client_flags;
38: static enum {
1.52 nicm 39: CLIENT_EXIT_NONE,
40: CLIENT_EXIT_DETACHED,
41: CLIENT_EXIT_DETACHED_HUP,
42: CLIENT_EXIT_LOST_TTY,
43: CLIENT_EXIT_TERMINATED,
44: CLIENT_EXIT_LOST_SERVER,
45: CLIENT_EXIT_EXITED,
46: CLIENT_EXIT_SERVER_EXITED,
47: } client_exitreason = CLIENT_EXIT_NONE;
1.133 nicm 48: static int client_exitflag;
1.114 nicm 49: static int client_exitval;
50: static enum msgtype client_exittype;
51: static const char *client_exitsession;
1.115 nicm 52: static const char *client_execshell;
53: static const char *client_execcmd;
1.114 nicm 54: static int client_attached;
1.132 nicm 55: static struct client_files client_files = RB_INITIALIZER(&client_files);
1.114 nicm 56:
57: static __dead void client_exec(const char *,const char *);
58: static int client_get_lock(char *);
59: static int client_connect(struct event_base *, const char *, int);
60: static void client_send_identify(const char *, const char *);
61: static void client_signal(int);
62: static void client_dispatch(struct imsg *, void *);
63: static void client_dispatch_attached(struct imsg *);
1.121 nicm 64: static void client_dispatch_wait(struct imsg *);
1.114 nicm 65: static const char *client_exit_message(void);
1.25 nicm 66:
1.49 nicm 67: /*
68: * Get server create lock. If already held then server start is happening in
1.110 nicm 69: * another client, so block until the lock is released and return -2 to
70: * retry. Return -1 on failure to continue and start the server anyway.
1.49 nicm 71: */
1.114 nicm 72: static int
1.49 nicm 73: client_get_lock(char *lockfile)
74: {
75: int lockfd;
76:
1.110 nicm 77: log_debug("lock file is %s", lockfile);
78:
1.109 nicm 79: if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1) {
1.110 nicm 80: log_debug("open failed: %s", strerror(errno));
81: return (-1);
1.109 nicm 82: }
1.49 nicm 83:
1.82 nicm 84: if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) {
85: log_debug("flock failed: %s", strerror(errno));
86: if (errno != EAGAIN)
87: return (lockfd);
88: while (flock(lockfd, LOCK_EX) == -1 && errno == EINTR)
1.49 nicm 89: /* nothing */;
90: close(lockfd);
1.110 nicm 91: return (-2);
1.49 nicm 92: }
1.82 nicm 93: log_debug("flock succeeded");
1.49 nicm 94:
95: return (lockfd);
96: }
97:
1.46 nicm 98: /* Connect client to server. */
1.114 nicm 99: static int
1.138 nicm 100: client_connect(struct event_base *base, const char *path, int flags)
1.1 nicm 101: {
1.26 nicm 102: struct sockaddr_un sa;
103: size_t size;
1.82 nicm 104: int fd, lockfd = -1, locked = 0;
105: char *lockfile = NULL;
1.1 nicm 106:
107: memset(&sa, 0, sizeof sa);
108: sa.sun_family = AF_UNIX;
109: size = strlcpy(sa.sun_path, path, sizeof sa.sun_path);
110: if (size >= sizeof sa.sun_path) {
111: errno = ENAMETOOLONG;
1.46 nicm 112: return (-1);
1.1 nicm 113: }
1.82 nicm 114: log_debug("socket is %s", path);
1.1 nicm 115:
1.49 nicm 116: retry:
1.10 nicm 117: if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
1.109 nicm 118: return (-1);
1.1 nicm 119:
1.82 nicm 120: log_debug("trying connect");
1.109 nicm 121: if (connect(fd, (struct sockaddr *)&sa, sizeof sa) == -1) {
1.82 nicm 122: log_debug("connect failed: %s", strerror(errno));
1.49 nicm 123: if (errno != ECONNREFUSED && errno != ENOENT)
124: goto failed;
1.138 nicm 125: if (~flags & CLIENT_STARTSERVER)
1.46 nicm 126: goto failed;
1.49 nicm 127: close(fd);
128:
1.82 nicm 129: if (!locked) {
130: xasprintf(&lockfile, "%s.lock", path);
1.110 nicm 131: if ((lockfd = client_get_lock(lockfile)) < 0) {
132: log_debug("didn't get lock (%d)", lockfd);
133:
1.82 nicm 134: free(lockfile);
1.110 nicm 135: lockfile = NULL;
136:
137: if (lockfd == -2)
138: goto retry;
1.82 nicm 139: }
1.110 nicm 140: log_debug("got lock (%d)", lockfd);
1.82 nicm 141:
142: /*
143: * Always retry at least once, even if we got the lock,
144: * because another client could have taken the lock,
145: * started the server and released the lock between our
146: * connect() and flock().
147: */
148: locked = 1;
1.49 nicm 149: goto retry;
1.78 nicm 150: }
1.82 nicm 151:
1.110 nicm 152: if (lockfd >= 0 && unlink(path) != 0 && errno != ENOENT) {
1.78 nicm 153: free(lockfile);
154: close(lockfd);
1.49 nicm 155: return (-1);
1.78 nicm 156: }
1.138 nicm 157: fd = server_start(client_proc, flags, base, lockfd, lockfile);
1.82 nicm 158: }
1.95 nicm 159:
1.110 nicm 160: if (locked && lockfd >= 0) {
1.58 nicm 161: free(lockfile);
1.49 nicm 162: close(lockfd);
1.1 nicm 163: }
1.47 nicm 164: setblocking(fd, 0);
1.46 nicm 165: return (fd);
166:
167: failed:
1.95 nicm 168: if (locked) {
169: free(lockfile);
170: close(lockfd);
171: }
1.46 nicm 172: close(fd);
173: return (-1);
174: }
175:
1.52 nicm 176: /* Get exit string from reason number. */
177: const char *
178: client_exit_message(void)
179: {
1.73 nicm 180: static char msg[256];
181:
1.52 nicm 182: switch (client_exitreason) {
183: case CLIENT_EXIT_NONE:
184: break;
185: case CLIENT_EXIT_DETACHED:
1.73 nicm 186: if (client_exitsession != NULL) {
187: xsnprintf(msg, sizeof msg, "detached "
188: "(from session %s)", client_exitsession);
189: return (msg);
190: }
1.52 nicm 191: return ("detached");
192: case CLIENT_EXIT_DETACHED_HUP:
1.73 nicm 193: if (client_exitsession != NULL) {
194: xsnprintf(msg, sizeof msg, "detached and SIGHUP "
195: "(from session %s)", client_exitsession);
196: return (msg);
197: }
1.52 nicm 198: return ("detached and SIGHUP");
199: case CLIENT_EXIT_LOST_TTY:
200: return ("lost tty");
201: case CLIENT_EXIT_TERMINATED:
202: return ("terminated");
203: case CLIENT_EXIT_LOST_SERVER:
1.131 nicm 204: return ("server exited unexpectedly");
1.52 nicm 205: case CLIENT_EXIT_EXITED:
206: return ("exited");
207: case CLIENT_EXIT_SERVER_EXITED:
208: return ("server exited");
209: }
210: return ("unknown reason");
211: }
212:
1.133 nicm 213: /* Exit if all streams flushed. */
214: static void
215: client_exit(void)
216: {
217: struct client_file *cf;
218: size_t left;
219: int waiting = 0;
220:
221: RB_FOREACH (cf, client_files, &client_files) {
222: if (cf->event == NULL)
223: continue;
224: left = EVBUFFER_LENGTH(cf->event->output);
225: if (left != 0) {
226: waiting++;
227: log_debug("file %u %zu bytes left", cf->stream, left);
228: }
229: }
230: if (waiting == 0)
231: proc_exit(client_proc);
232: }
233:
1.46 nicm 234: /* Client main loop. */
235: int
1.121 nicm 236: client_main(struct event_base *base, int argc, char **argv, int flags)
1.46 nicm 237: {
1.129 nicm 238: struct cmd_parse_result *pr;
1.46 nicm 239: struct cmd *cmd;
1.132 nicm 240: struct msg_command *data;
1.138 nicm 241: int fd, i;
1.98 nicm 242: const char *ttynam, *cwd;
1.48 nicm 243: pid_t ppid;
1.46 nicm 244: enum msgtype msg;
1.56 nicm 245: struct termios tio, saved_tio;
1.70 nicm 246: size_t size;
1.46 nicm 247:
1.99 nicm 248: /* Ignore SIGCHLD now or daemon() in the server will leave a zombie. */
249: signal(SIGCHLD, SIG_IGN);
250:
1.46 nicm 251: /* Set up the initial command. */
1.121 nicm 252: if (shell_command != NULL) {
1.46 nicm 253: msg = MSG_SHELL;
1.139 nicm 254: flags |= CLIENT_STARTSERVER;
1.46 nicm 255: } else if (argc == 0) {
256: msg = MSG_COMMAND;
1.138 nicm 257: flags |= CLIENT_STARTSERVER;
1.46 nicm 258: } else {
259: msg = MSG_COMMAND;
260:
261: /*
262: * It sucks parsing the command string twice (in client and
263: * later in server) but it is necessary to get the start server
264: * flag.
265: */
1.129 nicm 266: pr = cmd_parse_from_arguments(argc, argv, NULL);
267: if (pr->status == CMD_PARSE_SUCCESS) {
268: TAILQ_FOREACH(cmd, &pr->cmdlist->list, qentry) {
1.120 nicm 269: if (cmd->entry->flags & CMD_STARTSERVER)
1.138 nicm 270: flags |= CLIENT_STARTSERVER;
1.120 nicm 271: }
1.129 nicm 272: cmd_list_free(pr->cmdlist);
273: } else
274: free(pr->error);
1.46 nicm 275: }
276:
1.138 nicm 277: /* Save the flags. */
278: client_flags = flags;
279:
1.109 nicm 280: /* Create client process structure (starts logging). */
1.122 nicm 281: client_proc = proc_start("client");
282: proc_set_signals(client_proc, client_signal);
1.109 nicm 283:
1.82 nicm 284: /* Initialize the client socket and start the server. */
1.138 nicm 285: fd = client_connect(base, socket_path, client_flags);
1.46 nicm 286: if (fd == -1) {
1.87 nicm 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: }
1.46 nicm 294: return (1);
295: }
1.121 nicm 296: client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL);
1.99 nicm 297:
1.97 nicm 298: /* Save these before pledge(). */
1.128 nicm 299: if ((cwd = find_cwd()) == NULL && (cwd = find_home()) == NULL)
1.126 nicm 300: cwd = "/";
1.97 nicm 301: if ((ttynam = ttyname(STDIN_FILENO)) == NULL)
302: ttynam = "";
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: */
1.132 nicm 313: if (pledge(
314: "stdio rpath wpath cpath unix sendfd proc exec tty",
315: NULL) != 0)
1.97 nicm 316: fatal("pledge failed");
317:
318: /* Free stuff that is not used in the client. */
1.119 nicm 319: if (ptm_fd != -1)
320: close(ptm_fd);
1.100 nicm 321: options_free(global_options);
322: options_free(global_s_options);
323: options_free(global_w_options);
1.101 nicm 324: environ_free(global_environ);
1.46 nicm 325:
1.132 nicm 326: /* Set up control mode. */
1.93 nicm 327: if (client_flags & CLIENT_CONTROLCONTROL) {
1.118 nicm 328: if (tcgetattr(STDIN_FILENO, &saved_tio) != 0) {
329: fprintf(stderr, "tcgetattr failed: %s\n",
330: strerror(errno));
331: return (1);
332: }
1.56 nicm 333: cfmakeraw(&tio);
334: tio.c_iflag = ICRNL|IXANY;
335: tio.c_oflag = OPOST|ONLCR;
336: tio.c_lflag = NOKERNINFO;
337: tio.c_cflag = CREAD|CS8|HUPCL;
338: tio.c_cc[VMIN] = 1;
339: tio.c_cc[VTIME] = 0;
340: cfsetispeed(&tio, cfgetispeed(&saved_tio));
341: cfsetospeed(&tio, cfgetospeed(&saved_tio));
342: tcsetattr(STDIN_FILENO, TCSANOW, &tio);
343: }
1.1 nicm 344:
1.71 nicm 345: /* Send identify messages. */
1.98 nicm 346: client_send_identify(ttynam, cwd);
1.1 nicm 347:
1.46 nicm 348: /* Send first command. */
349: if (msg == MSG_COMMAND) {
1.70 nicm 350: /* How big is the command? */
351: size = 0;
352: for (i = 0; i < argc; i++)
353: size += strlen(argv[i]) + 1;
1.124 nicm 354: if (size > MAX_IMSGSIZE - (sizeof *data)) {
355: fprintf(stderr, "command too long\n");
356: return (1);
357: }
1.70 nicm 358: data = xmalloc((sizeof *data) + size);
1.46 nicm 359:
360: /* Prepare command for server. */
1.70 nicm 361: data->argc = argc;
1.83 nicm 362: if (cmd_pack_argv(argc, argv, (char *)(data + 1), size) != 0) {
1.55 nicm 363: fprintf(stderr, "command too long\n");
1.70 nicm 364: free(data);
1.46 nicm 365: return (1);
366: }
1.70 nicm 367: size += sizeof *data;
1.46 nicm 368:
1.70 nicm 369: /* Send the command. */
1.99 nicm 370: if (proc_send(client_peer, msg, -1, data, size) != 0) {
1.70 nicm 371: fprintf(stderr, "failed to send command\n");
372: free(data);
373: return (1);
374: }
375: free(data);
1.46 nicm 376: } else if (msg == MSG_SHELL)
1.99 nicm 377: proc_send(client_peer, msg, -1, NULL, 0);
1.1 nicm 378:
1.99 nicm 379: /* Start main loop. */
380: proc_loop(client_proc, NULL);
1.46 nicm 381:
1.115 nicm 382: /* Run command if user requested exec, instead of exiting. */
383: if (client_exittype == MSG_EXEC) {
384: if (client_flags & CLIENT_CONTROLCONTROL)
385: tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio);
386: client_exec(client_execshell, client_execcmd);
387: }
388:
1.46 nicm 389: /* Print the exit message, if any, and exit. */
1.48 nicm 390: if (client_attached) {
1.93 nicm 391: if (client_exitreason != CLIENT_EXIT_NONE)
1.52 nicm 392: printf("[%s]\n", client_exit_message());
1.48 nicm 393:
394: ppid = getppid();
395: if (client_exittype == MSG_DETACHKILL && ppid > 1)
396: kill(ppid, SIGHUP);
1.93 nicm 397: } else if (client_flags & CLIENT_CONTROLCONTROL) {
1.68 nicm 398: if (client_exitreason != CLIENT_EXIT_NONE)
399: printf("%%exit %s\n", client_exit_message());
400: else
401: printf("%%exit\n");
402: printf("\033\\");
1.56 nicm 403: tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio);
1.112 nicm 404: } else if (client_exitreason != CLIENT_EXIT_NONE)
1.109 nicm 405: fprintf(stderr, "%s\n", client_exit_message());
1.54 nicm 406: setblocking(STDIN_FILENO, 1);
1.46 nicm 407: return (client_exitval);
1.1 nicm 408: }
409:
1.71 nicm 410: /* Send identify messages to server. */
1.114 nicm 411: static void
1.98 nicm 412: client_send_identify(const char *ttynam, const char *cwd)
1.26 nicm 413: {
1.90 nicm 414: const char *s;
1.71 nicm 415: char **ss;
1.91 nicm 416: size_t sslen;
1.93 nicm 417: int fd, flags = client_flags;
1.90 nicm 418: pid_t pid;
1.71 nicm 419:
1.99 nicm 420: proc_send(client_peer, MSG_IDENTIFY_FLAGS, -1, &flags, sizeof flags);
1.71 nicm 421:
422: if ((s = getenv("TERM")) == NULL)
423: s = "";
1.99 nicm 424: proc_send(client_peer, MSG_IDENTIFY_TERM, -1, s, strlen(s) + 1);
1.71 nicm 425:
1.107 nicm 426: proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam,
427: strlen(ttynam) + 1);
1.99 nicm 428: proc_send(client_peer, MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1);
1.26 nicm 429:
1.50 nicm 430: if ((fd = dup(STDIN_FILENO)) == -1)
431: fatal("dup failed");
1.99 nicm 432: proc_send(client_peer, MSG_IDENTIFY_STDIN, fd, NULL, 0);
1.90 nicm 433:
434: pid = getpid();
1.99 nicm 435: proc_send(client_peer, MSG_IDENTIFY_CLIENTPID, -1, &pid, sizeof pid);
1.26 nicm 436:
1.91 nicm 437: for (ss = environ; *ss != NULL; ss++) {
438: sslen = strlen(*ss) + 1;
1.107 nicm 439: if (sslen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
440: continue;
441: proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen);
1.91 nicm 442: }
1.75 nicm 443:
1.99 nicm 444: proc_send(client_peer, MSG_IDENTIFY_DONE, -1, NULL, 0);
1.30 nicm 445: }
446:
1.132 nicm 447: /* File write error callback. */
1.114 nicm 448: static void
1.132 nicm 449: client_write_error_callback(__unused struct bufferevent *bev,
450: __unused short what, void *arg)
1.54 nicm 451: {
1.132 nicm 452: struct client_file *cf = arg;
1.54 nicm 453:
1.132 nicm 454: log_debug("write error file %d", cf->stream);
455:
456: bufferevent_free(cf->event);
457: cf->event = NULL;
458:
459: close(cf->fd);
460: cf->fd = -1;
1.134 nicm 461:
462: if (client_exitflag)
463: client_exit();
1.132 nicm 464: }
465:
466: /* File write callback. */
467: static void
468: client_write_callback(__unused struct bufferevent *bev, void *arg)
469: {
470: struct client_file *cf = arg;
471:
472: if (cf->closed && EVBUFFER_LENGTH(cf->event->output) == 0) {
473: bufferevent_free(cf->event);
474: close(cf->fd);
475: RB_REMOVE(client_files, &client_files, cf);
476: file_free(cf);
477: }
1.133 nicm 478:
479: if (client_exitflag)
480: client_exit();
1.132 nicm 481: }
482:
483: /* Open write file. */
484: static void
485: client_write_open(void *data, size_t datalen)
486: {
487: struct msg_write_open *msg = data;
1.135 nicm 488: const char *path;
1.132 nicm 489: struct msg_write_ready reply;
490: struct client_file find, *cf;
491: const int flags = O_NONBLOCK|O_WRONLY|O_CREAT;
492: int error = 0;
493:
1.135 nicm 494: if (datalen < sizeof *msg)
1.132 nicm 495: fatalx("bad MSG_WRITE_OPEN size");
1.135 nicm 496: if (datalen == sizeof *msg)
497: path = "-";
498: else
499: path = (const char *)(msg + 1);
500: log_debug("open write file %d %s", msg->stream, path);
1.132 nicm 501:
502: find.stream = msg->stream;
503: if ((cf = RB_FIND(client_files, &client_files, &find)) == NULL) {
504: cf = file_create(NULL, msg->stream, NULL, NULL);
505: RB_INSERT(client_files, &client_files, cf);
506: } else {
507: error = EBADF;
508: goto reply;
509: }
510: if (cf->closed) {
511: error = EBADF;
512: goto reply;
513: }
514:
515: cf->fd = -1;
516: if (msg->fd == -1)
1.135 nicm 517: cf->fd = open(path, msg->flags|flags, 0644);
1.132 nicm 518: else {
519: if (msg->fd != STDOUT_FILENO && msg->fd != STDERR_FILENO)
520: errno = EBADF;
521: else {
522: cf->fd = dup(msg->fd);
523: if (client_flags & CLIENT_CONTROL)
524: close(msg->fd); /* can only be used once */
525: }
526: }
527: if (cf->fd == -1) {
528: error = errno;
529: goto reply;
530: }
531:
532: cf->event = bufferevent_new(cf->fd, NULL, client_write_callback,
533: client_write_error_callback, cf);
534: bufferevent_enable(cf->event, EV_WRITE);
535: goto reply;
536:
537: reply:
538: reply.stream = msg->stream;
539: reply.error = error;
540: proc_send(client_peer, MSG_WRITE_READY, -1, &reply, sizeof reply);
541: }
542:
543: /* Write to client file. */
544: static void
545: client_write_data(void *data, size_t datalen)
546: {
547: struct msg_write_data *msg = data;
548: struct client_file find, *cf;
1.135 nicm 549: size_t size = datalen - sizeof *msg;
1.132 nicm 550:
1.135 nicm 551: if (datalen < sizeof *msg)
1.132 nicm 552: fatalx("bad MSG_WRITE size");
553: find.stream = msg->stream;
554: if ((cf = RB_FIND(client_files, &client_files, &find)) == NULL)
555: fatalx("unknown stream number");
1.135 nicm 556: log_debug("write %zu to file %d", size, cf->stream);
1.132 nicm 557:
558: if (cf->event != NULL)
1.135 nicm 559: bufferevent_write(cf->event, msg + 1, size);
1.132 nicm 560: }
561:
562: /* Close client file. */
563: static void
564: client_write_close(void *data, size_t datalen)
565: {
566: struct msg_write_close *msg = data;
567: struct client_file find, *cf;
1.54 nicm 568:
1.132 nicm 569: if (datalen != sizeof *msg)
570: fatalx("bad MSG_WRITE_CLOSE size");
571: find.stream = msg->stream;
572: if ((cf = RB_FIND(client_files, &client_files, &find)) == NULL)
573: fatalx("unknown stream number");
574: log_debug("close file %d", cf->stream);
575:
576: if (cf->event == NULL || EVBUFFER_LENGTH(cf->event->output) == 0) {
577: if (cf->event != NULL)
578: bufferevent_free(cf->event);
579: if (cf->fd != -1)
580: close(cf->fd);
581: RB_REMOVE(client_files, &client_files, cf);
582: file_free(cf);
583: }
1.54 nicm 584: }
585:
1.132 nicm 586: /* File read callback. */
1.114 nicm 587: static void
1.132 nicm 588: client_read_callback(__unused struct bufferevent *bev, void *arg)
1.57 nicm 589: {
1.132 nicm 590: struct client_file *cf = arg;
591: void *bdata;
592: size_t bsize;
1.135 nicm 593: struct msg_read_data *msg;
594: size_t msglen;
1.132 nicm 595:
1.135 nicm 596: msg = xmalloc(sizeof *msg);
1.132 nicm 597: for (;;) {
598: bdata = EVBUFFER_DATA(cf->event->input);
599: bsize = EVBUFFER_LENGTH(cf->event->input);
1.57 nicm 600:
1.132 nicm 601: if (bsize == 0)
1.57 nicm 602: break;
1.136 nicm 603: if (bsize > MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof *msg)
604: bsize = MAX_IMSGSIZE - IMSG_HEADER_SIZE - sizeof *msg;
1.132 nicm 605: log_debug("read %zu from file %d", bsize, cf->stream);
606:
1.135 nicm 607: msglen = (sizeof *msg) + bsize;
608: msg = xrealloc(msg, msglen);
609: msg->stream = cf->stream;
610: memcpy(msg + 1, bdata, bsize);
611: proc_send(client_peer, MSG_READ, -1, msg, msglen);
1.132 nicm 612:
613: evbuffer_drain(cf->event->input, bsize);
614: }
1.135 nicm 615: free(msg);
1.132 nicm 616: }
617:
618: /* File read error callback. */
619: static void
620: client_read_error_callback(__unused struct bufferevent *bev,
621: __unused short what, void *arg)
622: {
623: struct client_file *cf = arg;
624: struct msg_read_done msg;
625:
626: log_debug("read error file %d", cf->stream);
627:
628: msg.stream = cf->stream;
629: msg.error = 0;
630: proc_send(client_peer, MSG_READ_DONE, -1, &msg, sizeof msg);
631:
632: bufferevent_free(cf->event);
633: close(cf->fd);
634: RB_REMOVE(client_files, &client_files, cf);
635: file_free(cf);
636: }
637:
638: /* Open read file. */
639: static void
640: client_read_open(void *data, size_t datalen)
641: {
642: struct msg_read_open *msg = data;
1.135 nicm 643: const char *path;
1.132 nicm 644: struct msg_read_done reply;
645: struct client_file find, *cf;
646: const int flags = O_NONBLOCK|O_RDONLY;
1.140 ! nicm 647: int error;
1.132 nicm 648:
1.135 nicm 649: if (datalen < sizeof *msg)
1.132 nicm 650: fatalx("bad MSG_READ_OPEN size");
1.135 nicm 651: if (datalen == sizeof *msg)
652: path = "-";
653: else
654: path = (const char *)(msg + 1);
655: log_debug("open read file %d %s", msg->stream, path);
1.132 nicm 656:
657: find.stream = msg->stream;
658: if ((cf = RB_FIND(client_files, &client_files, &find)) == NULL) {
659: cf = file_create(NULL, msg->stream, NULL, NULL);
660: RB_INSERT(client_files, &client_files, cf);
661: } else {
662: error = EBADF;
663: goto reply;
1.57 nicm 664: }
1.132 nicm 665: if (cf->closed) {
666: error = EBADF;
667: goto reply;
668: }
669:
670: cf->fd = -1;
671: if (msg->fd == -1)
1.135 nicm 672: cf->fd = open(path, flags);
1.132 nicm 673: else {
674: if (msg->fd != STDIN_FILENO)
675: errno = EBADF;
676: else {
677: cf->fd = dup(msg->fd);
678: close(msg->fd); /* can only be used once */
679: }
680: }
681: if (cf->fd == -1) {
682: error = errno;
683: goto reply;
684: }
685:
686: cf->event = bufferevent_new(cf->fd, client_read_callback, NULL,
687: client_read_error_callback, cf);
688: bufferevent_enable(cf->event, EV_READ);
689: return;
690:
691: reply:
692: reply.stream = msg->stream;
693: reply.error = error;
694: proc_send(client_peer, MSG_READ_DONE, -1, &reply, sizeof reply);
1.57 nicm 695: }
696:
1.93 nicm 697: /* Run command in shell; used for -c. */
1.114 nicm 698: static __dead void
1.111 nicm 699: client_exec(const char *shell, const char *shellcmd)
1.93 nicm 700: {
701: const char *name, *ptr;
702: char *argv0;
703:
1.111 nicm 704: log_debug("shell %s, command %s", shell, shellcmd);
1.93 nicm 705:
706: ptr = strrchr(shell, '/');
707: if (ptr != NULL && *(ptr + 1) != '\0')
708: name = ptr + 1;
709: else
710: name = shell;
711: if (client_flags & CLIENT_LOGIN)
712: xasprintf(&argv0, "-%s", name);
713: else
714: xasprintf(&argv0, "%s", name);
715: setenv("SHELL", shell, 1);
716:
1.123 nicm 717: proc_clear_signals(client_proc, 1);
718:
1.93 nicm 719: setblocking(STDIN_FILENO, 1);
720: setblocking(STDOUT_FILENO, 1);
721: setblocking(STDERR_FILENO, 1);
722: closefrom(STDERR_FILENO + 1);
723:
1.111 nicm 724: execl(shell, argv0, "-c", shellcmd, (char *) NULL);
1.93 nicm 725: fatal("execl failed");
726: }
727:
1.99 nicm 728: /* Callback to handle signals in the client. */
1.114 nicm 729: static void
1.99 nicm 730: client_signal(int sig)
731: {
732: struct sigaction sigact;
733: int status;
734:
735: if (sig == SIGCHLD)
736: waitpid(WAIT_ANY, &status, WNOHANG);
737: else if (!client_attached) {
738: if (sig == SIGTERM)
739: proc_exit(client_proc);
740: } else {
741: switch (sig) {
742: case SIGHUP:
743: client_exitreason = CLIENT_EXIT_LOST_TTY;
744: client_exitval = 1;
745: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
746: break;
747: case SIGTERM:
748: client_exitreason = CLIENT_EXIT_TERMINATED;
749: client_exitval = 1;
750: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
751: break;
752: case SIGWINCH:
753: proc_send(client_peer, MSG_RESIZE, -1, NULL, 0);
754: break;
755: case SIGCONT:
756: memset(&sigact, 0, sizeof sigact);
757: sigemptyset(&sigact.sa_mask);
758: sigact.sa_flags = SA_RESTART;
759: sigact.sa_handler = SIG_IGN;
760: if (sigaction(SIGTSTP, &sigact, NULL) != 0)
761: fatal("sigaction failed");
762: proc_send(client_peer, MSG_WAKEUP, -1, NULL, 0);
763: break;
764: }
765: }
766: }
767:
768: /* Callback for client read events. */
1.114 nicm 769: static void
1.121 nicm 770: client_dispatch(struct imsg *imsg, __unused void *arg)
1.99 nicm 771: {
772: if (imsg == NULL) {
773: client_exitreason = CLIENT_EXIT_LOST_SERVER;
774: client_exitval = 1;
1.109 nicm 775: proc_exit(client_proc);
776: return;
777: }
778:
779: if (client_attached)
1.99 nicm 780: client_dispatch_attached(imsg);
781: else
1.121 nicm 782: client_dispatch_wait(imsg);
1.99 nicm 783: }
784:
1.46 nicm 785: /* Dispatch imsgs when in wait state (before MSG_READY). */
1.114 nicm 786: static void
1.121 nicm 787: client_dispatch_wait(struct imsg *imsg)
1.46 nicm 788: {
1.132 nicm 789: char *data;
790: ssize_t datalen;
791: int retval;
792: static int pledge_applied;
1.97 nicm 793:
794: /*
795: * "sendfd" is no longer required once all of the identify messages
796: * have been sent. We know the server won't send us anything until that
797: * point (because we don't ask it to), so we can drop "sendfd" once we
798: * get the first message from the server.
799: */
800: if (!pledge_applied) {
1.132 nicm 801: if (pledge(
802: "stdio rpath wpath cpath unix proc exec tty",
803: NULL) != 0)
1.97 nicm 804: fatal("pledge failed");
805: pledge_applied = 1;
1.132 nicm 806: }
1.46 nicm 807:
1.99 nicm 808: data = imsg->data;
809: datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1.60 nicm 810:
1.99 nicm 811: switch (imsg->hdr.type) {
812: case MSG_EXIT:
813: case MSG_SHUTDOWN:
814: if (datalen != sizeof retval && datalen != 0)
815: fatalx("bad MSG_EXIT size");
816: if (datalen == sizeof retval) {
817: memcpy(&retval, data, sizeof retval);
818: client_exitval = retval;
819: }
1.133 nicm 820: client_exitflag = 1;
821: client_exit();
1.99 nicm 822: break;
823: case MSG_READY:
824: if (datalen != 0)
825: fatalx("bad MSG_READY size");
1.54 nicm 826:
1.99 nicm 827: client_attached = 1;
828: proc_send(client_peer, MSG_RESIZE, -1, NULL, 0);
829: break;
830: case MSG_VERSION:
831: if (datalen != 0)
832: fatalx("bad MSG_VERSION size");
833:
834: fprintf(stderr, "protocol version mismatch "
835: "(client %d, server %u)\n", PROTOCOL_VERSION,
1.103 nicm 836: imsg->hdr.peerid & 0xff);
1.99 nicm 837: client_exitval = 1;
838: proc_exit(client_proc);
839: break;
840: case MSG_SHELL:
841: if (datalen == 0 || data[datalen - 1] != '\0')
842: fatalx("bad MSG_SHELL string");
843:
1.121 nicm 844: client_exec(data, shell_command);
1.99 nicm 845: /* NOTREACHED */
846: case MSG_DETACH:
847: case MSG_DETACHKILL:
848: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
849: break;
850: case MSG_EXITED:
851: proc_exit(client_proc);
1.132 nicm 852: break;
853: case MSG_READ_OPEN:
854: client_read_open(data, datalen);
855: break;
856: case MSG_WRITE_OPEN:
857: client_write_open(data, datalen);
858: break;
859: case MSG_WRITE:
860: client_write_data(data, datalen);
861: break;
862: case MSG_WRITE_CLOSE:
863: client_write_close(data, datalen);
1.137 nicm 864: break;
865: case MSG_OLDSTDERR:
866: case MSG_OLDSTDIN:
867: case MSG_OLDSTDOUT:
868: fprintf(stderr, "server version is too old for client\n");
869: proc_exit(client_proc);
1.99 nicm 870: break;
1.46 nicm 871: }
872: }
873:
874: /* Dispatch imsgs in attached state (after MSG_READY). */
1.114 nicm 875: static void
1.99 nicm 876: client_dispatch_attached(struct imsg *imsg)
1.9 nicm 877: {
1.69 nicm 878: struct sigaction sigact;
879: char *data;
1.99 nicm 880: ssize_t datalen;
1.9 nicm 881:
1.99 nicm 882: data = imsg->data;
883: datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1.12 nicm 884:
1.99 nicm 885: switch (imsg->hdr.type) {
886: case MSG_DETACH:
887: case MSG_DETACHKILL:
888: if (datalen == 0 || data[datalen - 1] != '\0')
889: fatalx("bad MSG_DETACH string");
890:
891: client_exitsession = xstrdup(data);
892: client_exittype = imsg->hdr.type;
893: if (imsg->hdr.type == MSG_DETACHKILL)
894: client_exitreason = CLIENT_EXIT_DETACHED_HUP;
895: else
896: client_exitreason = CLIENT_EXIT_DETACHED;
1.115 nicm 897: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
898: break;
899: case MSG_EXEC:
900: if (datalen == 0 || data[datalen - 1] != '\0' ||
901: strlen(data) + 1 == (size_t)datalen)
902: fatalx("bad MSG_EXEC string");
903: client_execcmd = xstrdup(data);
904: client_execshell = xstrdup(data + strlen(data) + 1);
905:
906: client_exittype = imsg->hdr.type;
1.99 nicm 907: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
908: break;
909: case MSG_EXIT:
910: if (datalen != 0 && datalen != sizeof (int))
911: fatalx("bad MSG_EXIT size");
1.9 nicm 912:
1.99 nicm 913: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
914: client_exitreason = CLIENT_EXIT_EXITED;
915: break;
916: case MSG_EXITED:
917: if (datalen != 0)
918: fatalx("bad MSG_EXITED size");
1.9 nicm 919:
1.99 nicm 920: proc_exit(client_proc);
921: break;
922: case MSG_SHUTDOWN:
923: if (datalen != 0)
924: fatalx("bad MSG_SHUTDOWN size");
925:
926: proc_send(client_peer, MSG_EXITING, -1, NULL, 0);
927: client_exitreason = CLIENT_EXIT_SERVER_EXITED;
928: client_exitval = 1;
929: break;
930: case MSG_SUSPEND:
931: if (datalen != 0)
932: fatalx("bad MSG_SUSPEND size");
933:
934: memset(&sigact, 0, sizeof sigact);
935: sigemptyset(&sigact.sa_mask);
936: sigact.sa_flags = SA_RESTART;
937: sigact.sa_handler = SIG_DFL;
938: if (sigaction(SIGTSTP, &sigact, NULL) != 0)
939: fatal("sigaction failed");
940: kill(getpid(), SIGTSTP);
941: break;
942: case MSG_LOCK:
943: if (datalen == 0 || data[datalen - 1] != '\0')
944: fatalx("bad MSG_LOCK string");
1.9 nicm 945:
1.99 nicm 946: system(data);
947: proc_send(client_peer, MSG_UNLOCK, -1, NULL, 0);
948: break;
1.9 nicm 949: }
1.1 nicm 950: }
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