tmux.c revision 1.42
1/* $OpenBSD: tmux.c,v 1.42 2009/09/04 15:15:24 nicm Exp $ */
2
3/*
4 * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
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/stat.h>
21
22#include <errno.h>
23#include <paths.h>
24#include <pwd.h>
25#include <signal.h>
26#include <stdlib.h>
27#include <string.h>
28#include <syslog.h>
29#include <unistd.h>
30
31#include "tmux.h"
32
33#ifdef DEBUG
34const char	*malloc_options = "AFGJPX";
35#endif
36
37volatile sig_atomic_t sigwinch;
38volatile sig_atomic_t sigterm;
39volatile sig_atomic_t sigcont;
40volatile sig_atomic_t sigchld;
41volatile sig_atomic_t sigusr1;
42volatile sig_atomic_t sigusr2;
43
44char		*cfg_file;
45struct options	 global_s_options;	/* session options */
46struct options	 global_w_options;	/* window options */
47struct environ	 global_environ;
48
49int		 server_locked;
50struct passwd	*server_locked_pw;
51u_int		 password_failures;
52time_t		 password_backoff;
53char		*server_password;
54time_t		 server_activity;
55
56int		 debug_level;
57int		 be_quiet;
58time_t		 start_time;
59char		*socket_path;
60int		 login_shell;
61
62__dead void	 usage(void);
63char 		*makesockpath(const char *);
64int		 prepare_unlock(enum msgtype *, void **, size_t *, int);
65int		 prepare_cmd(enum msgtype *, void **, size_t *, int, char **);
66int		 dispatch_imsg(struct client_ctx *, int *);
67
68__dead void
69usage(void)
70{
71	fprintf(stderr,
72	    "usage: %s [-28dlqUuv] [-f file] [-L socket-name]\n"
73	    "            [-S socket-path] [command [flags]]\n",
74	    __progname);
75	exit(1);
76}
77
78void
79logfile(const char *name)
80{
81	char	*path;
82
83	log_close();
84	if (debug_level > 0) {
85		xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
86		log_open_file(debug_level, path);
87		xfree(path);
88	}
89}
90
91void
92sighandler(int sig)
93{
94	int	saved_errno;
95
96	saved_errno = errno;
97	switch (sig) {
98	case SIGWINCH:
99		sigwinch = 1;
100		break;
101	case SIGTERM:
102		sigterm = 1;
103		break;
104	case SIGCHLD:
105		sigchld = 1;
106		break;
107	case SIGCONT:
108		sigcont = 1;
109		break;
110	case SIGUSR1:
111		sigusr1 = 1;
112		break;
113	case SIGUSR2:
114		sigusr2 = 1;
115		break;
116	}
117	errno = saved_errno;
118}
119
120void
121siginit(void)
122{
123	struct sigaction	 act;
124
125	memset(&act, 0, sizeof act);
126	sigemptyset(&act.sa_mask);
127	act.sa_flags = SA_RESTART;
128
129	act.sa_handler = SIG_IGN;
130	if (sigaction(SIGPIPE, &act, NULL) != 0)
131		fatal("sigaction failed");
132	if (sigaction(SIGINT, &act, NULL) != 0)
133		fatal("sigaction failed");
134	if (sigaction(SIGTSTP, &act, NULL) != 0)
135		fatal("sigaction failed");
136	if (sigaction(SIGQUIT, &act, NULL) != 0)
137		fatal("sigaction failed");
138
139	act.sa_handler = sighandler;
140	if (sigaction(SIGWINCH, &act, NULL) != 0)
141		fatal("sigaction failed");
142	if (sigaction(SIGTERM, &act, NULL) != 0)
143		fatal("sigaction failed");
144	if (sigaction(SIGCHLD, &act, NULL) != 0)
145		fatal("sigaction failed");
146	if (sigaction(SIGUSR1, &act, NULL) != 0)
147		fatal("sigaction failed");
148	if (sigaction(SIGUSR2, &act, NULL) != 0)
149		fatal("sigaction failed");
150}
151
152void
153sigreset(void)
154{
155	struct sigaction act;
156
157	memset(&act, 0, sizeof act);
158	sigemptyset(&act.sa_mask);
159
160	act.sa_handler = SIG_DFL;
161	if (sigaction(SIGPIPE, &act, NULL) != 0)
162		fatal("sigaction failed");
163	if (sigaction(SIGUSR1, &act, NULL) != 0)
164		fatal("sigaction failed");
165	if (sigaction(SIGUSR2, &act, NULL) != 0)
166		fatal("sigaction failed");
167	if (sigaction(SIGINT, &act, NULL) != 0)
168		fatal("sigaction failed");
169	if (sigaction(SIGTSTP, &act, NULL) != 0)
170		fatal("sigaction failed");
171	if (sigaction(SIGQUIT, &act, NULL) != 0)
172		fatal("sigaction failed");
173	if (sigaction(SIGWINCH, &act, NULL) != 0)
174		fatal("sigaction failed");
175	if (sigaction(SIGTERM, &act, NULL) != 0)
176		fatal("sigaction failed");
177	if (sigaction(SIGCHLD, &act, NULL) != 0)
178		fatal("sigaction failed");
179}
180
181const char *
182getshell(void)
183{
184	struct passwd	*pw;
185	const char	*shell;
186
187	shell = getenv("SHELL");
188	if (checkshell(shell))
189		return (shell);
190
191	pw = getpwuid(getuid());
192	if (pw != NULL && checkshell(pw->pw_shell))
193		return (pw->pw_shell);
194
195	return (_PATH_BSHELL);
196}
197
198int
199checkshell(const char *shell)
200{
201	if (shell == NULL || *shell == '\0' || areshell(shell))
202		return (0);
203	if (access(shell, X_OK) != 0)
204		return (0);
205	return (1);
206}
207
208int
209areshell(const char *shell)
210{
211	const char	*progname, *ptr;
212
213	if ((ptr = strrchr(shell, '/')) != NULL)
214		ptr++;
215	else
216		ptr = shell;
217	progname = __progname;
218	if (*progname == '-')
219		progname++;
220	if (strcmp(ptr, progname) == 0)
221		return (1);
222	return (0);
223}
224
225char *
226makesockpath(const char *label)
227{
228	char		base[MAXPATHLEN], *path;
229	struct stat	sb;
230	u_int		uid;
231
232	uid = getuid();
233	xsnprintf(base, MAXPATHLEN, "%s/tmux-%d", _PATH_TMP, uid);
234
235	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
236		return (NULL);
237
238	if (lstat(base, &sb) != 0)
239		return (NULL);
240	if (!S_ISDIR(sb.st_mode)) {
241		errno = ENOTDIR;
242		return (NULL);
243	}
244	if (sb.st_uid != uid || (sb.st_mode & (S_IRWXG|S_IRWXO)) != 0) {
245		errno = EACCES;
246		return (NULL);
247	}
248
249	xasprintf(&path, "%s/%s", base, label);
250	return (path);
251}
252
253int
254prepare_unlock(enum msgtype *msg, void **buf, size_t *len, int argc)
255{
256	static struct msg_unlock_data	 unlockdata;
257	char				*pass;
258
259	if (argc != 0) {
260		log_warnx("can't specify a command when unlocking");
261		return (-1);
262	}
263
264	if ((pass = getpass("Password:")) == NULL)
265		return (-1);
266
267	if (strlen(pass) >= sizeof unlockdata.pass) {
268		log_warnx("password too long");
269		return (-1);
270	}
271
272	strlcpy(unlockdata.pass, pass, sizeof unlockdata.pass);
273	memset(pass, 0, strlen(pass));
274
275	*buf = &unlockdata;
276	*len = sizeof unlockdata;
277
278	*msg = MSG_UNLOCK;
279	return (0);
280}
281
282int
283prepare_cmd(enum msgtype *msg, void **buf, size_t *len, int argc, char **argv)
284{
285	static struct msg_command_data	 cmddata;
286
287	client_fill_session(&cmddata);
288
289	cmddata.argc = argc;
290	if (cmd_pack_argv(argc, argv, cmddata.argv, sizeof cmddata.argv) != 0) {
291		log_warnx("command too long");
292		return (-1);
293	}
294
295	*buf = &cmddata;
296	*len = sizeof cmddata;
297
298	*msg = MSG_COMMAND;
299	return (0);
300}
301
302int
303main(int argc, char **argv)
304{
305	struct client_ctx	 cctx;
306	struct cmd_list		*cmdlist;
307 	struct cmd		*cmd;
308	struct pollfd	 	 pfd;
309	enum msgtype		 msg;
310	struct passwd		*pw;
311	struct options		*so, *wo;
312	char			*s, *path, *label, *home, *cause, **var;
313	char			 cwd[MAXPATHLEN];
314	void			*buf;
315	size_t			 len;
316	int	 		 retcode, opt, flags, unlock, cmdflags = 0;
317	int			 nfds;
318
319	unlock = flags = 0;
320	label = path = NULL;
321	login_shell = (**argv == '-');
322	while ((opt = getopt(argc, argv, "28df:lL:qS:uUv")) != -1) {
323		switch (opt) {
324		case '2':
325			flags |= IDENTIFY_256COLOURS;
326			flags &= ~IDENTIFY_88COLOURS;
327			break;
328		case '8':
329			flags |= IDENTIFY_88COLOURS;
330			flags &= ~IDENTIFY_256COLOURS;
331			break;
332		case 'd':
333			flags |= IDENTIFY_HASDEFAULTS;
334			break;
335		case 'f':
336			if (cfg_file != NULL)
337				xfree(cfg_file);
338			cfg_file = xstrdup(optarg);
339			break;
340		case 'l':
341			login_shell = 1;
342			break;
343		case 'L':
344			if (label != NULL)
345				xfree(label);
346			label = xstrdup(optarg);
347			break;
348		case 'q':
349			be_quiet = 1;
350			break;
351		case 'S':
352			if (path != NULL)
353				xfree(path);
354			path = xstrdup(optarg);
355			break;
356		case 'u':
357			flags |= IDENTIFY_UTF8;
358			break;
359		case 'U':
360			unlock = 1;
361			break;
362		case 'v':
363			debug_level++;
364			break;
365                default:
366			usage();
367                }
368        }
369	argc -= optind;
370	argv += optind;
371
372	log_open_tty(debug_level);
373	siginit();
374
375	if (!(flags & IDENTIFY_UTF8)) {
376		/*
377		 * If the user has set whichever of LC_ALL, LC_CTYPE or LANG
378		 * exist (in that order) to contain UTF-8, it is a safe
379		 * assumption that either they are using a UTF-8 terminal, or
380		 * if not they know that output from UTF-8-capable programs may
381		 * be wrong.
382		 */
383		if ((s = getenv("LC_ALL")) == NULL) {
384			if ((s = getenv("LC_CTYPE")) == NULL)
385				s = getenv("LANG");
386		}
387		if (s != NULL && (strcasestr(s, "UTF-8") != NULL ||
388		    strcasestr(s, "UTF8") != NULL))
389			flags |= IDENTIFY_UTF8;
390	}
391
392	environ_init(&global_environ);
393 	for (var = environ; *var != NULL; var++)
394		environ_put(&global_environ, *var);
395
396	options_init(&global_s_options, NULL);
397	so = &global_s_options;
398	options_set_number(so, "base-index", 0);
399	options_set_number(so, "bell-action", BELL_ANY);
400	options_set_number(so, "buffer-limit", 9);
401	options_set_string(so, "default-command", "%s", "");
402	options_set_string(so, "default-shell", "%s", getshell());
403	options_set_string(so, "default-terminal", "screen");
404	options_set_number(so, "display-panes-colour", 4);
405	options_set_number(so, "display-panes-time", 1000);
406	options_set_number(so, "display-time", 750);
407	options_set_number(so, "history-limit", 2000);
408	options_set_number(so, "lock-after-time", 0);
409	options_set_number(so, "message-attr", 0);
410	options_set_number(so, "message-bg", 3);
411	options_set_number(so, "message-fg", 0);
412	options_set_number(so, "prefix", '\002');
413	options_set_number(so, "repeat-time", 500);
414	options_set_number(so, "set-remain-on-exit", 0);
415	options_set_number(so, "set-titles", 0);
416	options_set_number(so, "status", 1);
417	options_set_number(so, "status-attr", 0);
418	options_set_number(so, "status-bg", 2);
419	options_set_number(so, "status-fg", 0);
420	options_set_number(so, "status-interval", 15);
421	options_set_number(so, "status-justify", 0);
422	options_set_number(so, "status-keys", MODEKEY_EMACS);
423	options_set_string(so, "status-left", "[#S]");
424	options_set_number(so, "status-left-attr", 0);
425	options_set_number(so, "status-left-bg", 8);
426	options_set_number(so, "status-left-fg", 8);
427	options_set_number(so, "status-left-length", 10);
428	options_set_string(so, "status-right", "\"#22T\" %%H:%%M %%d-%%b-%%y");
429	options_set_number(so, "status-right-attr", 0);
430	options_set_number(so, "status-right-bg", 8);
431	options_set_number(so, "status-right-fg", 8);
432	options_set_number(so, "status-right-length", 40);
433	options_set_string(so, "terminal-overrides",
434	    "*88col*:colors=88,*256col*:colors=256");
435	options_set_string(so, "update-environment", "DISPLAY "
436	    "WINDOWID SSH_ASKPASS SSH_AUTH_SOCK SSH_AGENT_PID SSH_CONNECTION");
437	options_set_number(so, "visual-activity", 0);
438	options_set_number(so, "visual-bell", 0);
439	options_set_number(so, "visual-content", 0);
440
441	options_init(&global_w_options, NULL);
442	wo = &global_w_options;
443	options_set_number(wo, "aggressive-resize", 0);
444	options_set_number(wo, "automatic-rename", 1);
445	options_set_number(wo, "clock-mode-colour", 4);
446	options_set_number(wo, "clock-mode-style", 1);
447	options_set_number(wo, "force-height", 0);
448	options_set_number(wo, "force-width", 0);
449	options_set_number(wo, "main-pane-height", 24);
450	options_set_number(wo, "main-pane-width", 81);
451	options_set_number(wo, "mode-attr", 0);
452	options_set_number(wo, "mode-bg", 3);
453	options_set_number(wo, "mode-fg", 0);
454	options_set_number(wo, "mode-keys", MODEKEY_EMACS);
455	options_set_number(wo, "mode-mouse", 0);
456	options_set_number(wo, "monitor-activity", 0);
457	options_set_string(wo, "monitor-content", "%s", "");
458	options_set_number(wo, "window-status-attr", 0);
459	options_set_number(wo, "window-status-bg", 8);
460	options_set_number(wo, "window-status-current-attr", 0);
461	options_set_number(wo, "window-status-current-bg", 8);
462	options_set_number(wo, "window-status-current-fg", 8);
463	options_set_number(wo, "window-status-fg", 8);
464	options_set_number(wo, "xterm-keys", 0);
465 	options_set_number(wo, "remain-on-exit", 0);
466
467 	if (flags & IDENTIFY_UTF8) {
468		options_set_number(so, "status-utf8", 1);
469		options_set_number(wo, "utf8", 1);
470	} else {
471		options_set_number(so, "status-utf8", 0);
472		options_set_number(wo, "utf8", 0);
473	}
474
475	if (getcwd(cwd, sizeof cwd) == NULL) {
476		pw = getpwuid(getuid());
477		if (pw->pw_dir != NULL && *pw->pw_dir != '\0')
478			strlcpy(cwd, pw->pw_dir, sizeof cwd);
479		else
480			strlcpy(cwd, "/", sizeof cwd);
481	}
482	options_set_string(so, "default-path", "%s", cwd);
483
484	if (cfg_file == NULL) {
485		home = getenv("HOME");
486		if (home == NULL || *home == '\0') {
487			pw = getpwuid(getuid());
488			if (pw != NULL)
489				home = pw->pw_dir;
490		}
491		xasprintf(&cfg_file, "%s/%s", home, DEFAULT_CFG);
492		if (access(cfg_file, R_OK) != 0) {
493			xfree(cfg_file);
494			cfg_file = NULL;
495		}
496	} else {
497		if (access(cfg_file, R_OK) != 0) {
498			log_warn("%s", cfg_file);
499			exit(1);
500		}
501	}
502
503	if (label == NULL)
504		label = xstrdup("default");
505	if (path == NULL && (path = makesockpath(label)) == NULL) {
506		log_warn("can't create socket");
507		exit(1);
508	}
509	xfree(label);
510
511	if (unlock) {
512		if (prepare_unlock(&msg, &buf, &len, argc) != 0)
513			exit(1);
514	} else {
515		if (prepare_cmd(&msg, &buf, &len, argc, argv) != 0)
516			exit(1);
517	}
518
519	if (unlock)
520		cmdflags &= ~CMD_STARTSERVER;
521	else if (argc == 0)	/* new-session is the default */
522		cmdflags |= CMD_STARTSERVER|CMD_SENDENVIRON;
523	else {
524		/*
525		 * It sucks parsing the command string twice (in client and
526		 * later in server) but it is necessary to get the start server
527		 * flag.
528		 */
529		if ((cmdlist = cmd_list_parse(argc, argv, &cause)) == NULL) {
530			log_warnx("%s", cause);
531			exit(1);
532		}
533		cmdflags &= ~CMD_STARTSERVER;
534		TAILQ_FOREACH(cmd, cmdlist, qentry) {
535			if (cmd->entry->flags & CMD_STARTSERVER)
536				cmdflags |= CMD_STARTSERVER;
537			if (cmd->entry->flags & CMD_SENDENVIRON)
538				cmdflags |= CMD_SENDENVIRON;
539		}
540		cmd_list_free(cmdlist);
541	}
542
543 	memset(&cctx, 0, sizeof cctx);
544	if (client_init(path, &cctx, cmdflags, flags) != 0)
545		exit(1);
546	xfree(path);
547
548	client_write_server(&cctx, msg, buf, len);
549	memset(buf, 0, len);
550
551	retcode = 0;
552	for (;;) {
553		pfd.fd = cctx.ibuf.fd;
554		pfd.events = POLLIN;
555		if (cctx.ibuf.w.queued != 0)
556			pfd.events |= POLLOUT;
557
558		if ((nfds = poll(&pfd, 1, INFTIM)) == -1) {
559			if (errno == EAGAIN || errno == EINTR)
560				continue;
561			fatal("poll failed");
562		}
563		if (nfds == 0)
564			continue;
565
566		if (pfd.revents & (POLLERR|POLLHUP|POLLNVAL))
567			fatalx("socket error");
568
569                if (pfd.revents & POLLIN) {
570			if (dispatch_imsg(&cctx, &retcode) != 0)
571				break;
572		}
573
574		if (pfd.revents & POLLOUT) {
575			if (msgbuf_write(&cctx.ibuf.w) < 0)
576				fatalx("msgbuf_write failed");
577		}
578	}
579
580	options_free(&global_s_options);
581	options_free(&global_w_options);
582
583	return (retcode);
584}
585
586int
587dispatch_imsg(struct client_ctx *cctx, int *retcode)
588{
589	struct imsg		imsg;
590	ssize_t			n, datalen;
591	struct msg_print_data	printdata;
592
593        if ((n = imsg_read(&cctx->ibuf)) == -1 || n == 0)
594		fatalx("imsg_read failed");
595
596	for (;;) {
597		if ((n = imsg_get(&cctx->ibuf, &imsg)) == -1)
598			fatalx("imsg_get failed");
599		if (n == 0)
600			return (0);
601		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
602
603		switch (imsg.hdr.type) {
604		case MSG_EXIT:
605		case MSG_SHUTDOWN:
606			if (datalen != 0)
607				fatalx("bad MSG_EXIT size");
608
609			return (-1);
610		case MSG_ERROR:
611			*retcode = 1;
612			/* FALLTHROUGH */
613		case MSG_PRINT:
614			if (datalen != sizeof printdata)
615				fatalx("bad MSG_PRINT size");
616			memcpy(&printdata, imsg.data, sizeof printdata);
617			printdata.msg[(sizeof printdata.msg) - 1] = '\0';
618
619			log_info("%s", printdata.msg);
620			break;
621		case MSG_READY:
622			if (datalen != 0)
623				fatalx("bad MSG_READY size");
624
625			*retcode = client_main(cctx);
626			return (-1);
627		case MSG_VERSION:
628			if (datalen != 0)
629				fatalx("bad MSG_VERSION size");
630
631			log_warnx("protocol version mismatch (client %u, "
632			    "server %u)", PROTOCOL_VERSION, imsg.hdr.peerid);
633			*retcode = 1;
634			return (-1);
635		default:
636			fatalx("unexpected message");
637		}
638
639		imsg_free(&imsg);
640	}
641}
642