28d00fe4 |
1 | /* |
2 | * Pseudo-tty backend for pterm. |
3 | * |
4 | * Unlike the other backends, data for this one is not neatly |
5 | * encapsulated into a data structure, because it wouldn't make |
6 | * sense to do so - the utmp stuff has to be done before a backend |
7 | * is initialised, and starting a second pterm from the same |
8 | * process would therefore be infeasible because privileges would |
9 | * already have been dropped. Hence, I haven't bothered to keep the |
10 | * data dynamically allocated: instead, the backend handle is just |
11 | * a null pointer and ignored everywhere. |
12 | */ |
13 | |
054d8535 |
14 | #define _XOPEN_SOURCE |
88e6b9ca |
15 | #define _XOPEN_SOURCE_EXTENDED |
74aca06d |
16 | #define _GNU_SOURCE |
054d8535 |
17 | |
1709795f |
18 | #include <stdio.h> |
19 | #include <stdlib.h> |
054d8535 |
20 | #include <string.h> |
21 | #include <unistd.h> |
a0e16eb1 |
22 | #include <signal.h> |
054d8535 |
23 | #include <fcntl.h> |
88e6b9ca |
24 | #include <termios.h> |
be4f86de |
25 | #include <grp.h> |
755a6d84 |
26 | #include <utmp.h> |
27 | #include <pwd.h> |
28 | #include <time.h> |
a0e16eb1 |
29 | #include <sys/types.h> |
d4e1d591 |
30 | #include <sys/stat.h> |
a0e16eb1 |
31 | #include <sys/wait.h> |
88e6b9ca |
32 | #include <sys/ioctl.h> |
0f33f9d1 |
33 | #include <errno.h> |
1709795f |
34 | |
35 | #include "putty.h" |
36 | |
37 | #ifndef FALSE |
38 | #define FALSE 0 |
39 | #endif |
40 | #ifndef TRUE |
41 | #define TRUE 1 |
42 | #endif |
43 | |
755a6d84 |
44 | #ifndef UTMP_FILE |
45 | #define UTMP_FILE "/var/run/utmp" |
46 | #endif |
47 | #ifndef WTMP_FILE |
48 | #define WTMP_FILE "/var/log/wtmp" |
49 | #endif |
50 | #ifndef LASTLOG_FILE |
51 | #ifdef _PATH_LASTLOG |
52 | #define LASTLOG_FILE _PATH_LASTLOG |
53 | #else |
54 | #define LASTLOG_FILE "/var/log/lastlog" |
55 | #endif |
56 | #endif |
57 | |
f51dc031 |
58 | /* |
59 | * Set up a default for vaguely sane systems. The idea is that if |
60 | * OMIT_UTMP is not defined, then at least one of the symbols which |
61 | * enable particular forms of utmp processing should be, if only so |
62 | * that a link error can warn you that you should have defined |
63 | * OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is |
64 | * the only such symbol. |
65 | */ |
66 | #ifndef OMIT_UTMP |
67 | #if !defined HAVE_PUTUTLINE |
68 | #define HAVE_PUTUTLINE |
69 | #endif |
70 | #endif |
71 | |
74aca06d |
72 | static Config pty_cfg; |
73 | static int pty_master_fd; |
a8327734 |
74 | static void *pty_frontend; |
95c47834 |
75 | static char pty_name[FILENAME_MAX]; |
74aca06d |
76 | static int pty_signal_pipe[2]; |
a0e16eb1 |
77 | static int pty_child_pid; |
f278d6f8 |
78 | static int pty_term_width, pty_term_height; |
74aca06d |
79 | static int pty_child_dead, pty_finished; |
80 | static int pty_exit_code; |
6169c758 |
81 | char **pty_argv; |
1d009ae7 |
82 | int use_pty_argv = TRUE; |
054d8535 |
83 | |
74aca06d |
84 | static void pty_close(void); |
85 | |
d4e1d591 |
86 | #ifndef OMIT_UTMP |
87 | static int pty_utmp_helper_pid, pty_utmp_helper_pipe; |
88 | static int pty_stamped_utmp = 0; |
89 | static struct utmp utmp_entry; |
90 | |
95c47834 |
91 | static void setup_utmp(char *ttyname, char *location) |
755a6d84 |
92 | { |
755a6d84 |
93 | #ifdef HAVE_LASTLOG |
94 | struct lastlog lastlog_entry; |
95 | FILE *lastlog; |
96 | #endif |
97 | struct passwd *pw; |
755a6d84 |
98 | FILE *wtmp; |
4764563f |
99 | time_t uttime; |
755a6d84 |
100 | |
101 | pw = getpwuid(getuid()); |
102 | memset(&utmp_entry, 0, sizeof(utmp_entry)); |
103 | utmp_entry.ut_type = USER_PROCESS; |
104 | utmp_entry.ut_pid = getpid(); |
105 | strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line)); |
106 | strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id)); |
107 | strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user)); |
108 | strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host)); |
4764563f |
109 | /* Apparently there are some architectures where (struct utmp).ut_time |
110 | * is not essentially time_t (e.g. Linux amd64). Hence the temporary. */ |
111 | time(&uttime); |
112 | utmp_entry.ut_time = uttime; /* may truncate */ |
755a6d84 |
113 | |
114 | #if defined HAVE_PUTUTLINE |
115 | utmpname(UTMP_FILE); |
116 | setutent(); |
117 | pututline(&utmp_entry); |
118 | endutent(); |
119 | #endif |
120 | |
121 | if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) { |
122 | fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp); |
123 | fclose(wtmp); |
124 | } |
125 | |
126 | #ifdef HAVE_LASTLOG |
127 | memset(&lastlog_entry, 0, sizeof(lastlog_entry)); |
128 | strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line)); |
129 | strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host)); |
130 | time(&lastlog_entry.ll_time); |
131 | if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) { |
132 | fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET); |
133 | fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog); |
134 | fclose(lastlog); |
135 | } |
136 | #endif |
137 | |
f51dc031 |
138 | pty_stamped_utmp = 1; |
139 | |
755a6d84 |
140 | } |
141 | |
142 | static void cleanup_utmp(void) |
143 | { |
755a6d84 |
144 | FILE *wtmp; |
4764563f |
145 | time_t uttime; |
755a6d84 |
146 | |
95c47834 |
147 | if (!pty_stamped_utmp) |
f51dc031 |
148 | return; |
149 | |
755a6d84 |
150 | utmp_entry.ut_type = DEAD_PROCESS; |
151 | memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user)); |
4764563f |
152 | time(&uttime); |
153 | utmp_entry.ut_time = uttime; |
755a6d84 |
154 | |
155 | if ((wtmp = fopen(WTMP_FILE, "a")) != NULL) { |
156 | fwrite(&utmp_entry, 1, sizeof(utmp_entry), wtmp); |
157 | fclose(wtmp); |
158 | } |
159 | |
160 | memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line)); |
161 | utmp_entry.ut_time = 0; |
162 | |
163 | #if defined HAVE_PUTUTLINE |
164 | utmpname(UTMP_FILE); |
165 | setutent(); |
166 | pututline(&utmp_entry); |
167 | endutent(); |
168 | #endif |
169 | |
f51dc031 |
170 | pty_stamped_utmp = 0; /* ensure we never double-cleanup */ |
755a6d84 |
171 | } |
d4e1d591 |
172 | #endif |
755a6d84 |
173 | |
a0e16eb1 |
174 | static void sigchld_handler(int signum) |
175 | { |
74aca06d |
176 | write(pty_signal_pipe[1], "x", 1); |
a0e16eb1 |
177 | } |
178 | |
d4e1d591 |
179 | #ifndef OMIT_UTMP |
755a6d84 |
180 | static void fatal_sig_handler(int signum) |
181 | { |
0f33f9d1 |
182 | putty_signal(signum, SIG_DFL); |
755a6d84 |
183 | cleanup_utmp(); |
184 | setuid(getuid()); |
185 | raise(signum); |
186 | } |
d4e1d591 |
187 | #endif |
755a6d84 |
188 | |
95c47834 |
189 | static void pty_open_master(void) |
1709795f |
190 | { |
be4f86de |
191 | #ifdef BSD_PTYS |
95c47834 |
192 | const char chars1[] = "pqrstuvwxyz"; |
193 | const char chars2[] = "0123456789abcdef"; |
194 | const char *p1, *p2; |
195 | char master_name[20]; |
196 | struct group *gp; |
197 | |
198 | for (p1 = chars1; *p1; p1++) |
199 | for (p2 = chars2; *p2; p2++) { |
200 | sprintf(master_name, "/dev/pty%c%c", *p1, *p2); |
201 | pty_master_fd = open(master_name, O_RDWR); |
202 | if (pty_master_fd >= 0) { |
203 | if (geteuid() == 0 || |
204 | access(master_name, R_OK | W_OK) == 0) |
205 | goto got_one; |
206 | close(pty_master_fd); |
be4f86de |
207 | } |
95c47834 |
208 | } |
be4f86de |
209 | |
95c47834 |
210 | /* If we get here, we couldn't get a tty at all. */ |
211 | fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n"); |
212 | exit(1); |
be4f86de |
213 | |
95c47834 |
214 | got_one: |
215 | strcpy(pty_name, master_name); |
216 | pty_name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */ |
217 | |
218 | /* We need to chown/chmod the /dev/ttyXX device. */ |
219 | gp = getgrnam("tty"); |
220 | chown(pty_name, getuid(), gp ? gp->gr_gid : -1); |
221 | chmod(pty_name, 0600); |
be4f86de |
222 | #else |
054d8535 |
223 | pty_master_fd = open("/dev/ptmx", O_RDWR); |
224 | |
225 | if (pty_master_fd < 0) { |
226 | perror("/dev/ptmx: open"); |
227 | exit(1); |
228 | } |
229 | |
230 | if (grantpt(pty_master_fd) < 0) { |
231 | perror("grantpt"); |
232 | exit(1); |
233 | } |
234 | |
235 | if (unlockpt(pty_master_fd) < 0) { |
236 | perror("unlockpt"); |
237 | exit(1); |
238 | } |
239 | |
95c47834 |
240 | pty_name[FILENAME_MAX-1] = '\0'; |
241 | strncpy(pty_name, ptsname(pty_master_fd), FILENAME_MAX-1); |
be4f86de |
242 | #endif |
95c47834 |
243 | } |
054d8535 |
244 | |
95c47834 |
245 | /* |
246 | * Pre-initialisation. This is here to get around the fact that GTK |
247 | * doesn't like being run in setuid/setgid programs (probably |
248 | * sensibly). So before we initialise GTK - and therefore before we |
249 | * even process the command line - we check to see if we're running |
250 | * set[ug]id. If so, we open our pty master _now_, chown it as |
251 | * necessary, and drop privileges. We can always close it again |
252 | * later. If we're potentially going to be doing utmp as well, we |
253 | * also fork off a utmp helper process and communicate with it by |
254 | * means of a pipe; the utmp helper will keep privileges in order |
255 | * to clean up utmp when we exit (i.e. when its end of our pipe |
256 | * closes). |
257 | */ |
258 | void pty_pre_init(void) |
259 | { |
d4e1d591 |
260 | #ifndef OMIT_UTMP |
95c47834 |
261 | pid_t pid; |
262 | int pipefd[2]; |
d4e1d591 |
263 | #endif |
95c47834 |
264 | |
0f33f9d1 |
265 | /* set the child signal handler straight away; it needs to be set |
266 | * before we ever fork. */ |
267 | putty_signal(SIGCHLD, sigchld_handler); |
95c47834 |
268 | pty_master_fd = -1; |
269 | |
270 | if (geteuid() != getuid() || getegid() != getgid()) { |
271 | pty_open_master(); |
39baeaa4 |
272 | } |
273 | |
95c47834 |
274 | #ifndef OMIT_UTMP |
39baeaa4 |
275 | /* |
95c47834 |
276 | * Fork off the utmp helper. |
755a6d84 |
277 | */ |
95c47834 |
278 | if (pipe(pipefd) < 0) { |
279 | perror("pterm: pipe"); |
280 | exit(1); |
281 | } |
282 | pid = fork(); |
283 | if (pid < 0) { |
284 | perror("pterm: fork"); |
285 | exit(1); |
286 | } else if (pid == 0) { |
287 | char display[128], buffer[128]; |
288 | int dlen, ret; |
289 | |
290 | close(pipefd[1]); |
291 | /* |
292 | * Now sit here until we receive a display name from the |
293 | * other end of the pipe, and then stamp utmp. Unstamp utmp |
294 | * again, and exit, when the pipe closes. |
295 | */ |
296 | |
297 | dlen = 0; |
298 | while (1) { |
299 | |
300 | ret = read(pipefd[0], buffer, lenof(buffer)); |
301 | if (ret <= 0) { |
302 | cleanup_utmp(); |
0f33f9d1 |
303 | _exit(0); |
95c47834 |
304 | } else if (!pty_stamped_utmp) { |
305 | if (dlen < lenof(display)) |
306 | memcpy(display+dlen, buffer, |
307 | min(ret, lenof(display)-dlen)); |
308 | if (buffer[ret-1] == '\0') { |
309 | /* |
310 | * Now we have a display name. NUL-terminate |
311 | * it, and stamp utmp. |
312 | */ |
313 | display[lenof(display)-1] = '\0'; |
314 | /* |
315 | * Trap as many fatal signals as we can in the |
316 | * hope of having the best possible chance to |
317 | * clean up utmp before termination. We are |
318 | * unfortunately unprotected against SIGKILL, |
319 | * but that's life. |
320 | */ |
0f33f9d1 |
321 | putty_signal(SIGHUP, fatal_sig_handler); |
322 | putty_signal(SIGINT, fatal_sig_handler); |
323 | putty_signal(SIGQUIT, fatal_sig_handler); |
324 | putty_signal(SIGILL, fatal_sig_handler); |
325 | putty_signal(SIGABRT, fatal_sig_handler); |
326 | putty_signal(SIGFPE, fatal_sig_handler); |
327 | putty_signal(SIGPIPE, fatal_sig_handler); |
328 | putty_signal(SIGALRM, fatal_sig_handler); |
329 | putty_signal(SIGTERM, fatal_sig_handler); |
330 | putty_signal(SIGSEGV, fatal_sig_handler); |
331 | putty_signal(SIGUSR1, fatal_sig_handler); |
332 | putty_signal(SIGUSR2, fatal_sig_handler); |
755a6d84 |
333 | #ifdef SIGBUS |
0f33f9d1 |
334 | putty_signal(SIGBUS, fatal_sig_handler); |
755a6d84 |
335 | #endif |
336 | #ifdef SIGPOLL |
0f33f9d1 |
337 | putty_signal(SIGPOLL, fatal_sig_handler); |
755a6d84 |
338 | #endif |
339 | #ifdef SIGPROF |
0f33f9d1 |
340 | putty_signal(SIGPROF, fatal_sig_handler); |
755a6d84 |
341 | #endif |
342 | #ifdef SIGSYS |
0f33f9d1 |
343 | putty_signal(SIGSYS, fatal_sig_handler); |
755a6d84 |
344 | #endif |
345 | #ifdef SIGTRAP |
0f33f9d1 |
346 | putty_signal(SIGTRAP, fatal_sig_handler); |
755a6d84 |
347 | #endif |
348 | #ifdef SIGVTALRM |
0f33f9d1 |
349 | putty_signal(SIGVTALRM, fatal_sig_handler); |
755a6d84 |
350 | #endif |
351 | #ifdef SIGXCPU |
0f33f9d1 |
352 | putty_signal(SIGXCPU, fatal_sig_handler); |
755a6d84 |
353 | #endif |
354 | #ifdef SIGXFSZ |
0f33f9d1 |
355 | putty_signal(SIGXFSZ, fatal_sig_handler); |
755a6d84 |
356 | #endif |
357 | #ifdef SIGIO |
0f33f9d1 |
358 | putty_signal(SIGIO, fatal_sig_handler); |
95c47834 |
359 | #endif |
95c47834 |
360 | setup_utmp(pty_name, display); |
361 | } |
362 | } |
363 | } |
364 | } else { |
365 | close(pipefd[0]); |
366 | pty_utmp_helper_pid = pid; |
367 | pty_utmp_helper_pipe = pipefd[1]; |
368 | } |
755a6d84 |
369 | #endif |
95c47834 |
370 | |
371 | /* Drop privs. */ |
372 | { |
95c47834 |
373 | #ifndef HAVE_NO_SETRESUID |
d4e1d591 |
374 | int gid = getgid(), uid = getuid(); |
95c47834 |
375 | int setresgid(gid_t, gid_t, gid_t); |
376 | int setresuid(uid_t, uid_t, uid_t); |
377 | setresgid(gid, gid, gid); |
378 | setresuid(uid, uid, uid); |
379 | #else |
380 | setgid(getgid()); |
381 | setuid(getuid()); |
382 | #endif |
383 | } |
384 | } |
385 | |
74aca06d |
386 | int pty_select_result(int fd, int event) |
387 | { |
388 | char buf[4096]; |
389 | int ret; |
390 | int finished = FALSE; |
391 | |
392 | if (fd == pty_master_fd && event == 1) { |
393 | |
394 | ret = read(pty_master_fd, buf, sizeof(buf)); |
395 | |
396 | /* |
397 | * Clean termination condition is that either ret == 0, or ret |
398 | * < 0 and errno == EIO. Not sure why the latter, but it seems |
399 | * to happen. Boo. |
400 | */ |
401 | if (ret == 0 || (ret < 0 && errno == EIO)) { |
402 | /* |
403 | * We assume a clean exit if the pty has closed but the |
404 | * actual child process hasn't. The only way I can |
405 | * imagine this happening is if it detaches itself from |
406 | * the pty and goes daemonic - in which case the |
407 | * expected usage model would precisely _not_ be for |
408 | * the pterm window to hang around! |
409 | */ |
410 | finished = TRUE; |
411 | if (!pty_child_dead) |
412 | pty_exit_code = 0; |
413 | } else if (ret < 0) { |
414 | perror("read pty master"); |
415 | exit(1); |
416 | } else if (ret > 0) { |
417 | from_backend(pty_frontend, 0, buf, ret); |
418 | } |
419 | } else if (fd == pty_signal_pipe[0]) { |
420 | pid_t pid; |
421 | int status; |
422 | char c[1]; |
423 | |
424 | read(pty_signal_pipe[0], c, 1); /* ignore its value; it'll be `x' */ |
425 | |
426 | do { |
427 | pid = waitpid(-1, &status, WNOHANG); |
428 | if (pid == pty_child_pid && |
429 | (WIFEXITED(status) || WIFSIGNALED(status))) { |
430 | /* |
431 | * The primary child process died. We could keep |
432 | * the terminal open for remaining subprocesses to |
433 | * output to, but conventional wisdom seems to feel |
434 | * that that's the Wrong Thing for an xterm-alike, |
435 | * so we bail out now (though we don't necessarily |
436 | * _close_ the window, depending on the state of |
437 | * Close On Exit). This would be easy enough to |
438 | * change or make configurable if necessary. |
439 | */ |
440 | pty_exit_code = status; |
441 | pty_child_dead = TRUE; |
442 | finished = TRUE; |
443 | } |
444 | } while(pid > 0); |
445 | } |
446 | |
447 | if (finished && !pty_finished) { |
448 | uxsel_del(pty_master_fd); |
449 | pty_close(); |
450 | pty_master_fd = -1; |
451 | |
452 | pty_finished = TRUE; |
453 | |
454 | /* |
455 | * This is a slight layering-violation sort of hack: only |
456 | * if we're not closing on exit (COE is set to Never, or to |
457 | * Only On Clean and it wasn't a clean exit) do we output a |
458 | * `terminated' message. |
459 | */ |
460 | if (pty_cfg.close_on_exit == FORCE_OFF || |
461 | (pty_cfg.close_on_exit == AUTO && pty_exit_code != 0)) { |
462 | char message[512]; |
463 | if (WIFEXITED(pty_exit_code)) |
464 | sprintf(message, "\r\n[pterm: process terminated with exit" |
465 | " code %d]\r\n", WEXITSTATUS(pty_exit_code)); |
466 | else if (WIFSIGNALED(pty_exit_code)) |
467 | #ifdef HAVE_NO_STRSIGNAL |
468 | sprintf(message, "\r\n[pterm: process terminated on signal" |
469 | " %d]\r\n", WTERMSIG(pty_exit_code)); |
470 | #else |
471 | sprintf(message, "\r\n[pterm: process terminated on signal" |
472 | " %d (%.400s)]\r\n", WTERMSIG(pty_exit_code), |
473 | strsignal(WTERMSIG(pty_exit_code))); |
474 | #endif |
475 | from_backend(pty_frontend, 0, message, strlen(message)); |
476 | } |
39934deb |
477 | |
478 | notify_remote_exit(pty_frontend); |
74aca06d |
479 | } |
480 | return !finished; |
481 | } |
482 | |
483 | static void pty_uxsel_setup(void) |
484 | { |
485 | uxsel_set(pty_master_fd, 1, pty_select_result); |
486 | uxsel_set(pty_signal_pipe[0], 1, pty_select_result); |
487 | } |
488 | |
95c47834 |
489 | /* |
490 | * Called to set up the pty. |
491 | * |
492 | * Returns an error message, or NULL on success. |
493 | * |
494 | * Also places the canonical host name into `realhost'. It must be |
495 | * freed by the caller. |
496 | */ |
cbe2d68f |
497 | static const char *pty_init(void *frontend, void **backend_handle, Config *cfg, |
79bf227b |
498 | char *host, int port, char **realhost, int nodelay, |
499 | int keepalive) |
95c47834 |
500 | { |
501 | int slavefd; |
502 | pid_t pid, pgrp; |
7af753e6 |
503 | long windowid; |
95c47834 |
504 | |
a8327734 |
505 | pty_frontend = frontend; |
28d00fe4 |
506 | *backend_handle = NULL; /* we can't sensibly use this, sadly */ |
507 | |
74aca06d |
508 | pty_cfg = *cfg; /* structure copy */ |
86916870 |
509 | pty_term_width = cfg->width; |
510 | pty_term_height = cfg->height; |
f278d6f8 |
511 | |
95c47834 |
512 | if (pty_master_fd < 0) |
513 | pty_open_master(); |
514 | |
515 | /* |
516 | * Set the backspace character to be whichever of ^H and ^? is |
517 | * specified by bksp_is_delete. |
518 | */ |
519 | { |
520 | struct termios attrs; |
521 | tcgetattr(pty_master_fd, &attrs); |
86916870 |
522 | attrs.c_cc[VERASE] = cfg->bksp_is_delete ? '\177' : '\010'; |
95c47834 |
523 | tcsetattr(pty_master_fd, TCSANOW, &attrs); |
524 | } |
525 | |
d4e1d591 |
526 | #ifndef OMIT_UTMP |
95c47834 |
527 | /* |
528 | * Stamp utmp (that is, tell the utmp helper process to do so), |
529 | * or not. |
530 | */ |
58dcb876 |
531 | if (!cfg->stamp_utmp) { |
95c47834 |
532 | close(pty_utmp_helper_pipe); /* just let the child process die */ |
58dcb876 |
533 | pty_utmp_helper_pipe = -1; |
534 | } else { |
a8327734 |
535 | char *location = get_x_display(pty_frontend); |
95c47834 |
536 | int len = strlen(location)+1, pos = 0; /* +1 to include NUL */ |
537 | while (pos < len) { |
538 | int ret = write(pty_utmp_helper_pipe, location+pos, len - pos); |
539 | if (ret < 0) { |
540 | perror("pterm: writing to utmp helper process"); |
541 | close(pty_utmp_helper_pipe); /* arrgh, just give up */ |
58dcb876 |
542 | pty_utmp_helper_pipe = -1; |
95c47834 |
543 | break; |
544 | } |
545 | pos += ret; |
546 | } |
547 | } |
d4e1d591 |
548 | #endif |
755a6d84 |
549 | |
7af753e6 |
550 | windowid = get_windowid(pty_frontend); |
551 | |
755a6d84 |
552 | /* |
054d8535 |
553 | * Fork and execute the command. |
554 | */ |
555 | pid = fork(); |
556 | if (pid < 0) { |
557 | perror("fork"); |
88e6b9ca |
558 | exit(1); |
054d8535 |
559 | } |
560 | |
561 | if (pid == 0) { |
562 | int i; |
563 | /* |
564 | * We are the child. |
565 | */ |
d37c2d81 |
566 | |
95c47834 |
567 | slavefd = open(pty_name, O_RDWR); |
d37c2d81 |
568 | if (slavefd < 0) { |
569 | perror("slave pty: open"); |
0f33f9d1 |
570 | _exit(1); |
d37c2d81 |
571 | } |
572 | |
054d8535 |
573 | close(pty_master_fd); |
054d8535 |
574 | fcntl(slavefd, F_SETFD, 0); /* don't close on exec */ |
575 | dup2(slavefd, 0); |
576 | dup2(slavefd, 1); |
577 | dup2(slavefd, 2); |
578 | setsid(); |
d37c2d81 |
579 | ioctl(slavefd, TIOCSCTTY, 1); |
580 | pgrp = getpid(); |
581 | tcsetpgrp(slavefd, pgrp); |
ea0716c6 |
582 | setpgid(pgrp, pgrp); |
95c47834 |
583 | close(open(pty_name, O_WRONLY, 0)); |
ea0716c6 |
584 | setpgid(pgrp, pgrp); |
054d8535 |
585 | /* Close everything _else_, for tidiness. */ |
586 | for (i = 3; i < 1024; i++) |
587 | close(i); |
fe9548aa |
588 | { |
86916870 |
589 | char term_env_var[10 + sizeof(cfg->termtype)]; |
590 | sprintf(term_env_var, "TERM=%s", cfg->termtype); |
fe9548aa |
591 | putenv(term_env_var); |
592 | } |
7af753e6 |
593 | { |
594 | char windowid_env_var[40]; |
595 | sprintf(windowid_env_var, "WINDOWID=%ld", windowid); |
596 | putenv(windowid_env_var); |
597 | } |
73feed4f |
598 | { |
599 | char *e = cfg->environmt; |
600 | char *var, *varend, *val, *varval; |
601 | while (*e) { |
602 | var = e; |
603 | while (*e && *e != '\t') e++; |
604 | varend = e; |
605 | if (*e == '\t') e++; |
606 | val = e; |
607 | while (*e) e++; |
608 | e++; |
609 | |
610 | varval = dupprintf("%.*s=%s", varend-var, var, val); |
611 | putenv(varval); |
612 | /* |
613 | * We must not free varval, since putenv links it |
614 | * into the environment _in place_. Weird, but |
615 | * there we go. Memory usage will be rationalised |
616 | * as soon as we exec anyway. |
617 | */ |
618 | } |
619 | } |
620 | |
8bf5c419 |
621 | /* |
622 | * SIGINT and SIGQUIT may have been set to ignored by our |
623 | * parent, particularly by things like sh -c 'pterm &' and |
3be6dd89 |
624 | * some window managers. SIGCHLD, meanwhile, has been |
625 | * tinkered with by the watchdog process. Reverse all this |
626 | * for our child process. |
8bf5c419 |
627 | */ |
0f33f9d1 |
628 | putty_signal(SIGINT, SIG_DFL); |
629 | putty_signal(SIGQUIT, SIG_DFL); |
3be6dd89 |
630 | { |
631 | sigset_t set; |
632 | sigemptyset(&set); |
633 | sigaddset(&set, SIGCHLD); |
634 | sigprocmask(SIG_UNBLOCK, &set, NULL); |
635 | } |
6169c758 |
636 | if (pty_argv) |
637 | execvp(pty_argv[0], pty_argv); |
c8ee61b9 |
638 | else { |
639 | char *shell = getenv("SHELL"); |
640 | char *shellname; |
86916870 |
641 | if (cfg->login_shell) { |
c8ee61b9 |
642 | char *p = strrchr(shell, '/'); |
3d88e64d |
643 | shellname = snewn(2+strlen(shell), char); |
c8ee61b9 |
644 | p = p ? p+1 : shell; |
645 | sprintf(shellname, "-%s", p); |
646 | } else |
647 | shellname = shell; |
648 | execl(getenv("SHELL"), shellname, NULL); |
649 | } |
650 | |
054d8535 |
651 | /* |
652 | * If we're here, exec has gone badly foom. |
653 | */ |
654 | perror("exec"); |
0f33f9d1 |
655 | _exit(127); |
054d8535 |
656 | } else { |
a0e16eb1 |
657 | pty_child_pid = pid; |
658 | pty_child_dead = FALSE; |
74aca06d |
659 | pty_finished = FALSE; |
0f33f9d1 |
660 | } |
054d8535 |
661 | |
74aca06d |
662 | if (pipe(pty_signal_pipe) < 0) { |
663 | perror("pipe"); |
664 | exit(1); |
665 | } |
666 | pty_uxsel_setup(); |
667 | |
1709795f |
668 | return NULL; |
669 | } |
670 | |
86916870 |
671 | static void pty_reconfig(void *handle, Config *cfg) |
672 | { |
6b0eeb4e |
673 | /* |
674 | * We don't have much need to reconfigure this backend, but |
675 | * unfortunately we do need to pick up the setting of Close On |
676 | * Exit so we know whether to give a `terminated' message. |
677 | */ |
678 | pty_cfg = *cfg; /* structure copy */ |
86916870 |
679 | } |
680 | |
681 | /* |
6b0eeb4e |
682 | * Stub routine (never called in pterm). |
cb60dcb3 |
683 | */ |
684 | static void pty_free(void *handle) |
685 | { |
686 | } |
687 | |
cb60dcb3 |
688 | /* |
1709795f |
689 | * Called to send data down the pty. |
690 | */ |
28d00fe4 |
691 | static int pty_send(void *handle, char *buf, int len) |
1709795f |
692 | { |
90cfd8f4 |
693 | if (pty_master_fd < 0) |
694 | return 0; /* ignore all writes if fd closed */ |
695 | |
054d8535 |
696 | while (len > 0) { |
697 | int ret = write(pty_master_fd, buf, len); |
698 | if (ret < 0) { |
699 | perror("write pty master"); |
700 | exit(1); |
701 | } |
702 | buf += ret; |
703 | len -= ret; |
704 | } |
1709795f |
705 | return 0; |
706 | } |
707 | |
74aca06d |
708 | static void pty_close(void) |
90cfd8f4 |
709 | { |
710 | if (pty_master_fd >= 0) { |
711 | close(pty_master_fd); |
712 | pty_master_fd = -1; |
713 | } |
d4e1d591 |
714 | #ifndef OMIT_UTMP |
58dcb876 |
715 | if (pty_utmp_helper_pipe >= 0) { |
716 | close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */ |
717 | pty_utmp_helper_pipe = -1; |
718 | } |
d4e1d591 |
719 | #endif |
90cfd8f4 |
720 | } |
721 | |
1709795f |
722 | /* |
723 | * Called to query the current socket sendability status. |
724 | */ |
28d00fe4 |
725 | static int pty_sendbuffer(void *handle) |
1709795f |
726 | { |
727 | return 0; |
728 | } |
729 | |
730 | /* |
731 | * Called to set the size of the window |
732 | */ |
28d00fe4 |
733 | static void pty_size(void *handle, int width, int height) |
1709795f |
734 | { |
88e6b9ca |
735 | struct winsize size; |
736 | |
f278d6f8 |
737 | pty_term_width = width; |
738 | pty_term_height = height; |
739 | |
740 | size.ws_row = (unsigned short)pty_term_height; |
741 | size.ws_col = (unsigned short)pty_term_width; |
a8327734 |
742 | size.ws_xpixel = (unsigned short) pty_term_width * |
743 | font_dimension(pty_frontend, 0); |
744 | size.ws_ypixel = (unsigned short) pty_term_height * |
745 | font_dimension(pty_frontend, 1); |
88e6b9ca |
746 | ioctl(pty_master_fd, TIOCSWINSZ, (void *)&size); |
1709795f |
747 | return; |
748 | } |
749 | |
750 | /* |
751 | * Send special codes. |
752 | */ |
28d00fe4 |
753 | static void pty_special(void *handle, Telnet_Special code) |
1709795f |
754 | { |
755 | /* Do nothing! */ |
756 | return; |
757 | } |
758 | |
125105d1 |
759 | /* |
760 | * Return a list of the special codes that make sense in this |
761 | * protocol. |
762 | */ |
763 | static const struct telnet_special *pty_get_specials(void *handle) |
764 | { |
765 | /* |
766 | * Hmm. When I get round to having this actually usable, it |
767 | * might be quite nice to have the ability to deliver a few |
768 | * well chosen signals to the child process - SIGINT, SIGTERM, |
769 | * SIGKILL at least. |
770 | */ |
771 | return NULL; |
772 | } |
773 | |
28d00fe4 |
774 | static Socket pty_socket(void *handle) |
1709795f |
775 | { |
776 | return NULL; /* shouldn't ever be needed */ |
777 | } |
778 | |
28d00fe4 |
779 | static int pty_sendok(void *handle) |
1709795f |
780 | { |
781 | return 1; |
782 | } |
783 | |
28d00fe4 |
784 | static void pty_unthrottle(void *handle, int backlog) |
1709795f |
785 | { |
786 | /* do nothing */ |
787 | } |
788 | |
28d00fe4 |
789 | static int pty_ldisc(void *handle, int option) |
1709795f |
790 | { |
791 | return 0; /* neither editing nor echoing */ |
792 | } |
793 | |
b9d7bcad |
794 | static void pty_provide_ldisc(void *handle, void *ldisc) |
795 | { |
796 | /* This is a stub. */ |
797 | } |
798 | |
a8327734 |
799 | static void pty_provide_logctx(void *handle, void *logctx) |
800 | { |
801 | /* This is a stub. */ |
802 | } |
803 | |
28d00fe4 |
804 | static int pty_exitcode(void *handle) |
1709795f |
805 | { |
74aca06d |
806 | if (!pty_finished) |
90cfd8f4 |
807 | return -1; /* not dead yet */ |
808 | else |
809 | return pty_exit_code; |
1709795f |
810 | } |
811 | |
812 | Backend pty_backend = { |
813 | pty_init, |
cb60dcb3 |
814 | pty_free, |
86916870 |
815 | pty_reconfig, |
1709795f |
816 | pty_send, |
817 | pty_sendbuffer, |
818 | pty_size, |
819 | pty_special, |
125105d1 |
820 | pty_get_specials, |
1709795f |
821 | pty_socket, |
822 | pty_exitcode, |
823 | pty_sendok, |
824 | pty_ldisc, |
b9d7bcad |
825 | pty_provide_ldisc, |
a8327734 |
826 | pty_provide_logctx, |
1709795f |
827 | pty_unthrottle, |
828 | 1 |
829 | }; |