1 /* $OpenBSD: tmux.c,v 1.188 2019/04/26 11:38:51 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/stat.h> 21 22 #include <err.h> 23 #include <errno.h> 24 #include <event.h> 25 #include <fcntl.h> 26 #include <langinfo.h> 27 #include <locale.h> 28 #include <paths.h> 29 #include <pwd.h> 30 #include <stdlib.h> 31 #include <string.h> 32 #include <time.h> 33 #include <unistd.h> 34 #include <util.h> 35 36 #include "tmux.h" 37 38 struct options *global_options; /* server options */ 39 struct options *global_s_options; /* session options */ 40 struct options *global_w_options; /* window options */ 41 struct environ *global_environ; 42 43 struct timeval start_time; 44 const char *socket_path; 45 int ptm_fd = -1; 46 const char *shell_command; 47 48 static __dead void usage(void); 49 static char *make_label(const char *, char **); 50 51 static const char *getshell(void); 52 static int checkshell(const char *); 53 54 static __dead void 55 usage(void) 56 { 57 fprintf(stderr, 58 "usage: %s [-2Cluv] [-c shell-command] [-f file] [-L socket-name]\n" 59 " [-S socket-path] [command [flags]]\n", 60 getprogname()); 61 exit(1); 62 } 63 64 static const char * 65 getshell(void) 66 { 67 struct passwd *pw; 68 const char *shell; 69 70 shell = getenv("SHELL"); 71 if (checkshell(shell)) 72 return (shell); 73 74 pw = getpwuid(getuid()); 75 if (pw != NULL && checkshell(pw->pw_shell)) 76 return (pw->pw_shell); 77 78 return (_PATH_BSHELL); 79 } 80 81 static int 82 checkshell(const char *shell) 83 { 84 if (shell == NULL || *shell != '/') 85 return (0); 86 if (areshell(shell)) 87 return (0); 88 if (access(shell, X_OK) != 0) 89 return (0); 90 return (1); 91 } 92 93 int 94 areshell(const char *shell) 95 { 96 const char *progname, *ptr; 97 98 if ((ptr = strrchr(shell, '/')) != NULL) 99 ptr++; 100 else 101 ptr = shell; 102 progname = getprogname(); 103 if (*progname == '-') 104 progname++; 105 if (strcmp(ptr, progname) == 0) 106 return (1); 107 return (0); 108 } 109 110 static char * 111 make_label(const char *label, char **cause) 112 { 113 char *base, resolved[PATH_MAX], *path, *s; 114 struct stat sb; 115 uid_t uid; 116 117 *cause = NULL; 118 119 if (label == NULL) 120 label = "default"; 121 uid = getuid(); 122 123 if ((s = getenv("TMUX_TMPDIR")) != NULL && *s != '\0') 124 xasprintf(&base, "%s/tmux-%ld", s, (long)uid); 125 else 126 xasprintf(&base, "%s/tmux-%ld", _PATH_TMP, (long)uid); 127 if (realpath(base, resolved) == NULL && 128 strlcpy(resolved, base, sizeof resolved) >= sizeof resolved) { 129 errno = ERANGE; 130 free(base); 131 goto fail; 132 } 133 134 if (mkdir(resolved, S_IRWXU) != 0 && errno != EEXIST) 135 goto fail; 136 if (lstat(resolved, &sb) != 0) 137 goto fail; 138 if (!S_ISDIR(sb.st_mode)) { 139 errno = ENOTDIR; 140 goto fail; 141 } 142 if (sb.st_uid != uid || (sb.st_mode & S_IRWXO) != 0) { 143 errno = EACCES; 144 goto fail; 145 } 146 xasprintf(&path, "%s/%s", resolved, label); 147 return (path); 148 149 fail: 150 xasprintf(cause, "error creating %s (%s)", resolved, strerror(errno)); 151 return (NULL); 152 } 153 154 void 155 setblocking(int fd, int state) 156 { 157 int mode; 158 159 if ((mode = fcntl(fd, F_GETFL)) != -1) { 160 if (!state) 161 mode |= O_NONBLOCK; 162 else 163 mode &= ~O_NONBLOCK; 164 fcntl(fd, F_SETFL, mode); 165 } 166 } 167 168 const char * 169 find_cwd(void) 170 { 171 char resolved1[PATH_MAX], resolved2[PATH_MAX]; 172 static char cwd[PATH_MAX]; 173 const char *pwd; 174 175 if (getcwd(cwd, sizeof cwd) == NULL) 176 return (NULL); 177 if ((pwd = getenv("PWD")) == NULL || *pwd == '\0') 178 return (cwd); 179 180 /* 181 * We want to use PWD so that symbolic links are maintained, 182 * but only if it matches the actual working directory. 183 */ 184 if (realpath(pwd, resolved1) == NULL) 185 return (cwd); 186 if (realpath(cwd, resolved2) == NULL) 187 return (cwd); 188 if (strcmp(resolved1, resolved2) != 0) 189 return (cwd); 190 return (pwd); 191 } 192 193 const char * 194 find_home(void) 195 { 196 struct passwd *pw; 197 static const char *home; 198 199 if (home != NULL) 200 return (home); 201 202 home = getenv("HOME"); 203 if (home == NULL || *home == '\0') { 204 pw = getpwuid(getuid()); 205 if (pw != NULL) 206 home = pw->pw_dir; 207 else 208 home = NULL; 209 } 210 211 return (home); 212 } 213 214 int 215 main(int argc, char **argv) 216 { 217 char *path, *label, *cause, **var; 218 const char *s, *shell, *cwd; 219 int opt, flags, keys; 220 const struct options_table_entry *oe; 221 222 if (setlocale(LC_CTYPE, "en_US.UTF-8") == NULL && 223 setlocale(LC_CTYPE, "C.UTF-8") == NULL) { 224 if (setlocale(LC_CTYPE, "") == NULL) 225 errx(1, "invalid LC_ALL, LC_CTYPE or LANG"); 226 s = nl_langinfo(CODESET); 227 if (strcasecmp(s, "UTF-8") != 0 && strcasecmp(s, "UTF8") != 0) 228 errx(1, "need UTF-8 locale (LC_CTYPE) but have %s", s); 229 } 230 231 setlocale(LC_TIME, ""); 232 tzset(); 233 234 if (**argv == '-') 235 flags = CLIENT_LOGIN; 236 else 237 flags = 0; 238 239 label = path = NULL; 240 while ((opt = getopt(argc, argv, "2c:Cdf:lL:qS:uUv")) != -1) { 241 switch (opt) { 242 case '2': 243 flags |= CLIENT_256COLOURS; 244 break; 245 case 'c': 246 shell_command = optarg; 247 break; 248 case 'C': 249 if (flags & CLIENT_CONTROL) 250 flags |= CLIENT_CONTROLCONTROL; 251 else 252 flags |= CLIENT_CONTROL; 253 break; 254 case 'f': 255 set_cfg_file(optarg); 256 break; 257 case 'l': 258 flags |= CLIENT_LOGIN; 259 break; 260 case 'L': 261 free(label); 262 label = xstrdup(optarg); 263 break; 264 case 'q': 265 break; 266 case 'S': 267 free(path); 268 path = xstrdup(optarg); 269 break; 270 case 'u': 271 flags |= CLIENT_UTF8; 272 break; 273 case 'v': 274 log_add_level(); 275 break; 276 default: 277 usage(); 278 } 279 } 280 argc -= optind; 281 argv += optind; 282 283 if (shell_command != NULL && argc != 0) 284 usage(); 285 286 if ((ptm_fd = getptmfd()) == -1) 287 err(1, "getptmfd"); 288 if (pledge("stdio rpath wpath cpath flock fattr unix getpw sendfd " 289 "recvfd proc exec tty ps", NULL) != 0) 290 err(1, "pledge"); 291 292 /* 293 * tmux is a UTF-8 terminal, so if TMUX is set, assume UTF-8. 294 * Otherwise, if the user has set LC_ALL, LC_CTYPE or LANG to contain 295 * UTF-8, it is a safe assumption that either they are using a UTF-8 296 * terminal, or if not they know that output from UTF-8-capable 297 * programs may be wrong. 298 */ 299 if (getenv("TMUX") != NULL) 300 flags |= CLIENT_UTF8; 301 else { 302 s = getenv("LC_ALL"); 303 if (s == NULL || *s == '\0') 304 s = getenv("LC_CTYPE"); 305 if (s == NULL || *s == '\0') 306 s = getenv("LANG"); 307 if (s == NULL || *s == '\0') 308 s = ""; 309 if (strcasestr(s, "UTF-8") != NULL || 310 strcasestr(s, "UTF8") != NULL) 311 flags |= CLIENT_UTF8; 312 } 313 314 global_environ = environ_create(); 315 for (var = environ; *var != NULL; var++) 316 environ_put(global_environ, *var); 317 if ((cwd = find_cwd()) != NULL) 318 environ_set(global_environ, "PWD", "%s", cwd); 319 320 global_options = options_create(NULL); 321 global_s_options = options_create(NULL); 322 global_w_options = options_create(NULL); 323 for (oe = options_table; oe->name != NULL; oe++) { 324 if (oe->scope == OPTIONS_TABLE_SERVER) 325 options_default(global_options, oe); 326 if (oe->scope == OPTIONS_TABLE_SESSION) 327 options_default(global_s_options, oe); 328 if (oe->scope == OPTIONS_TABLE_WINDOW) 329 options_default(global_w_options, oe); 330 } 331 332 /* 333 * The default shell comes from SHELL or from the user's passwd entry 334 * if available. 335 */ 336 shell = getshell(); 337 options_set_string(global_s_options, "default-shell", 0, "%s", shell); 338 339 /* Override keys to vi if VISUAL or EDITOR are set. */ 340 if ((s = getenv("VISUAL")) != NULL || (s = getenv("EDITOR")) != NULL) { 341 if (strrchr(s, '/') != NULL) 342 s = strrchr(s, '/') + 1; 343 if (strstr(s, "vi") != NULL) 344 keys = MODEKEY_VI; 345 else 346 keys = MODEKEY_EMACS; 347 options_set_number(global_s_options, "status-keys", keys); 348 options_set_number(global_w_options, "mode-keys", keys); 349 } 350 351 /* 352 * If socket is specified on the command-line with -S or -L, it is 353 * used. Otherwise, $TMUX is checked and if that fails "default" is 354 * used. 355 */ 356 if (path == NULL && label == NULL) { 357 s = getenv("TMUX"); 358 if (s != NULL && *s != '\0' && *s != ',') { 359 path = xstrdup(s); 360 path[strcspn(path, ",")] = '\0'; 361 } 362 } 363 if (path == NULL && (path = make_label(label, &cause)) == NULL) { 364 if (cause != NULL) { 365 fprintf(stderr, "%s\n", cause); 366 free(cause); 367 } 368 exit(1); 369 } 370 socket_path = path; 371 free(label); 372 373 /* Pass control to the client. */ 374 exit(client_main(event_init(), argc, argv, flags)); 375 } 376