28d00fe4 |
1 | /* |
2 | * Pseudo-tty backend for pterm. |
28d00fe4 |
3 | */ |
4 | |
74aca06d |
5 | #define _GNU_SOURCE |
054d8535 |
6 | |
1709795f |
7 | #include <stdio.h> |
8 | #include <stdlib.h> |
054d8535 |
9 | #include <string.h> |
10 | #include <unistd.h> |
a0e16eb1 |
11 | #include <signal.h> |
054d8535 |
12 | #include <fcntl.h> |
88e6b9ca |
13 | #include <termios.h> |
be4f86de |
14 | #include <grp.h> |
755a6d84 |
15 | #include <utmp.h> |
16 | #include <pwd.h> |
17 | #include <time.h> |
a0e16eb1 |
18 | #include <sys/types.h> |
d4e1d591 |
19 | #include <sys/stat.h> |
a0e16eb1 |
20 | #include <sys/wait.h> |
88e6b9ca |
21 | #include <sys/ioctl.h> |
0f33f9d1 |
22 | #include <errno.h> |
1709795f |
23 | |
24 | #include "putty.h" |
d6fa1947 |
25 | #include "tree234.h" |
1709795f |
26 | |
0b1df797 |
27 | #ifndef OMIT_UTMP |
bea25c48 |
28 | #include <utmpx.h> |
29 | #endif |
30 | |
1709795f |
31 | #ifndef FALSE |
32 | #define FALSE 0 |
33 | #endif |
34 | #ifndef TRUE |
35 | #define TRUE 1 |
36 | #endif |
37 | |
bea25c48 |
38 | /* updwtmpx() needs the name of the wtmp file. Try to find it. */ |
39 | #ifndef WTMPX_FILE |
40 | #ifdef _PATH_WTMPX |
41 | #define WTMPX_FILE _PATH_WTMPX |
42 | #else |
43 | #define WTMPX_FILE "/var/log/wtmpx" |
755a6d84 |
44 | #endif |
755a6d84 |
45 | #endif |
bea25c48 |
46 | |
755a6d84 |
47 | #ifndef LASTLOG_FILE |
48 | #ifdef _PATH_LASTLOG |
49 | #define LASTLOG_FILE _PATH_LASTLOG |
50 | #else |
51 | #define LASTLOG_FILE "/var/log/lastlog" |
52 | #endif |
53 | #endif |
54 | |
f51dc031 |
55 | /* |
56 | * Set up a default for vaguely sane systems. The idea is that if |
57 | * OMIT_UTMP is not defined, then at least one of the symbols which |
58 | * enable particular forms of utmp processing should be, if only so |
59 | * that a link error can warn you that you should have defined |
60 | * OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is |
61 | * the only such symbol. |
62 | */ |
63 | #ifndef OMIT_UTMP |
64 | #if !defined HAVE_PUTUTLINE |
65 | #define HAVE_PUTUTLINE |
66 | #endif |
67 | #endif |
68 | |
d6fa1947 |
69 | typedef struct pty_tag *Pty; |
70 | |
71 | /* |
72 | * The pty_signal_pipe, along with the SIGCHLD handler, must be |
73 | * process-global rather than session-specific. |
74 | */ |
75 | static int pty_signal_pipe[2] = { -1, -1 }; /* obviously bogus initial val */ |
76 | |
77 | struct pty_tag { |
78 | Config cfg; |
79 | int master_fd, slave_fd; |
80 | void *frontend; |
81 | char name[FILENAME_MAX]; |
82 | int child_pid; |
83 | int term_width, term_height; |
84 | int child_dead, finished; |
85 | int exit_code; |
86 | }; |
87 | |
88 | /* |
89 | * We store our pty backends in a tree sorted by master fd, so that |
90 | * when we get an uxsel notification we know which backend instance |
91 | * is the owner of the pty that caused it. |
92 | */ |
93 | static int pty_compare_by_fd(void *av, void *bv) |
94 | { |
95 | Pty a = (Pty)av; |
96 | Pty b = (Pty)bv; |
97 | |
98 | if (a->master_fd < b->master_fd) |
99 | return -1; |
100 | else if (a->master_fd > b->master_fd) |
101 | return +1; |
102 | return 0; |
103 | } |
104 | |
105 | static int pty_find_by_fd(void *av, void *bv) |
106 | { |
107 | int a = *(int *)av; |
108 | Pty b = (Pty)bv; |
109 | |
110 | if (a < b->master_fd) |
111 | return -1; |
112 | else if (a > b->master_fd) |
113 | return +1; |
114 | return 0; |
115 | } |
054d8535 |
116 | |
d6fa1947 |
117 | static tree234 *ptys_by_fd = NULL; |
118 | |
119 | /* |
120 | * We also have a tree sorted by child pid, so that when we wait() |
121 | * in response to the signal we know which backend instance is the |
122 | * owner of the process that caused the signal. |
123 | */ |
124 | static int pty_compare_by_pid(void *av, void *bv) |
125 | { |
126 | Pty a = (Pty)av; |
127 | Pty b = (Pty)bv; |
128 | |
129 | if (a->child_pid < b->child_pid) |
130 | return -1; |
131 | else if (a->child_pid > b->child_pid) |
132 | return +1; |
133 | return 0; |
134 | } |
135 | |
136 | static int pty_find_by_pid(void *av, void *bv) |
137 | { |
138 | int a = *(int *)av; |
139 | Pty b = (Pty)bv; |
140 | |
141 | if (a < b->child_pid) |
142 | return -1; |
143 | else if (a > b->child_pid) |
144 | return +1; |
145 | return 0; |
146 | } |
147 | |
148 | static tree234 *ptys_by_pid = NULL; |
149 | |
150 | /* |
151 | * If we are using pty_pre_init(), it will need to have already |
152 | * allocated a pty structure, which we must then return from |
153 | * pty_init() rather than allocating a new one. Here we store that |
154 | * structure between allocation and use. |
155 | * |
156 | * Note that although most of this module is entirely capable of |
157 | * handling multiple ptys in a single process, pty_pre_init() is |
158 | * fundamentally _dependent_ on there being at most one pty per |
159 | * process, so the normal static-data constraints don't apply. |
160 | * |
161 | * Likewise, since utmp is only used via pty_pre_init, it too must |
162 | * be single-instance, so we can declare utmp-related variables |
163 | * here. |
164 | */ |
165 | static Pty single_pty = NULL; |
74aca06d |
166 | |
d4e1d591 |
167 | #ifndef OMIT_UTMP |
168 | static int pty_utmp_helper_pid, pty_utmp_helper_pipe; |
d6fa1947 |
169 | static int pty_stamped_utmp; |
bea25c48 |
170 | static struct utmpx utmp_entry; |
d6fa1947 |
171 | #endif |
172 | |
173 | /* |
174 | * pty_argv is a grievous hack to allow a proper argv to be passed |
175 | * through from the Unix command line. Again, it doesn't really |
176 | * make sense outside a one-pty-per-process setup. |
177 | */ |
178 | char **pty_argv; |
d6fa1947 |
179 | |
180 | static void pty_close(Pty pty); |
d4e1d591 |
181 | |
d6fa1947 |
182 | #ifndef OMIT_UTMP |
95c47834 |
183 | static void setup_utmp(char *ttyname, char *location) |
755a6d84 |
184 | { |
755a6d84 |
185 | #ifdef HAVE_LASTLOG |
186 | struct lastlog lastlog_entry; |
187 | FILE *lastlog; |
188 | #endif |
189 | struct passwd *pw; |
bea25c48 |
190 | struct timeval tv; |
755a6d84 |
191 | |
192 | pw = getpwuid(getuid()); |
193 | memset(&utmp_entry, 0, sizeof(utmp_entry)); |
194 | utmp_entry.ut_type = USER_PROCESS; |
195 | utmp_entry.ut_pid = getpid(); |
196 | strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line)); |
197 | strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id)); |
198 | strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user)); |
199 | strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host)); |
bea25c48 |
200 | /* |
201 | * Apparently there are some architectures where (struct |
202 | * utmpx).ut_tv is not essentially struct timeval (e.g. Linux |
203 | * amd64). Hence the temporary. |
204 | */ |
205 | gettimeofday(&tv, NULL); |
206 | utmp_entry.ut_tv.tv_sec = tv.tv_sec; |
207 | utmp_entry.ut_tv.tv_usec = tv.tv_usec; |
755a6d84 |
208 | |
bea25c48 |
209 | setutxent(); |
210 | pututxline(&utmp_entry); |
211 | endutxent(); |
212 | |
213 | updwtmpx(WTMPX_FILE, &utmp_entry); |
755a6d84 |
214 | |
215 | #ifdef HAVE_LASTLOG |
216 | memset(&lastlog_entry, 0, sizeof(lastlog_entry)); |
217 | strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line)); |
218 | strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host)); |
219 | time(&lastlog_entry.ll_time); |
220 | if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) { |
221 | fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET); |
222 | fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog); |
223 | fclose(lastlog); |
224 | } |
225 | #endif |
226 | |
f51dc031 |
227 | pty_stamped_utmp = 1; |
228 | |
755a6d84 |
229 | } |
230 | |
231 | static void cleanup_utmp(void) |
232 | { |
bea25c48 |
233 | struct timeval tv; |
755a6d84 |
234 | |
95c47834 |
235 | if (!pty_stamped_utmp) |
f51dc031 |
236 | return; |
237 | |
755a6d84 |
238 | utmp_entry.ut_type = DEAD_PROCESS; |
239 | memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user)); |
bea25c48 |
240 | gettimeofday(&tv, NULL); |
241 | utmp_entry.ut_tv.tv_sec = tv.tv_sec; |
242 | utmp_entry.ut_tv.tv_usec = tv.tv_usec; |
755a6d84 |
243 | |
bea25c48 |
244 | updwtmpx(WTMPX_FILE, &utmp_entry); |
755a6d84 |
245 | |
246 | memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line)); |
bea25c48 |
247 | utmp_entry.ut_tv.tv_sec = 0; |
248 | utmp_entry.ut_tv.tv_usec = 0; |
755a6d84 |
249 | |
bea25c48 |
250 | setutxent(); |
251 | pututxline(&utmp_entry); |
252 | endutxent(); |
755a6d84 |
253 | |
f51dc031 |
254 | pty_stamped_utmp = 0; /* ensure we never double-cleanup */ |
755a6d84 |
255 | } |
d4e1d591 |
256 | #endif |
755a6d84 |
257 | |
a0e16eb1 |
258 | static void sigchld_handler(int signum) |
259 | { |
74aca06d |
260 | write(pty_signal_pipe[1], "x", 1); |
a0e16eb1 |
261 | } |
262 | |
d4e1d591 |
263 | #ifndef OMIT_UTMP |
755a6d84 |
264 | static void fatal_sig_handler(int signum) |
265 | { |
0f33f9d1 |
266 | putty_signal(signum, SIG_DFL); |
755a6d84 |
267 | cleanup_utmp(); |
268 | setuid(getuid()); |
269 | raise(signum); |
270 | } |
d4e1d591 |
271 | #endif |
755a6d84 |
272 | |
d6fa1947 |
273 | static int pty_open_slave(Pty pty) |
270d2e8d |
274 | { |
d6fa1947 |
275 | if (pty->slave_fd < 0) |
276 | pty->slave_fd = open(pty->name, O_RDWR); |
270d2e8d |
277 | |
d6fa1947 |
278 | return pty->slave_fd; |
270d2e8d |
279 | } |
280 | |
d6fa1947 |
281 | static void pty_open_master(Pty pty) |
1709795f |
282 | { |
be4f86de |
283 | #ifdef BSD_PTYS |
95c47834 |
284 | const char chars1[] = "pqrstuvwxyz"; |
285 | const char chars2[] = "0123456789abcdef"; |
286 | const char *p1, *p2; |
287 | char master_name[20]; |
288 | struct group *gp; |
289 | |
290 | for (p1 = chars1; *p1; p1++) |
291 | for (p2 = chars2; *p2; p2++) { |
292 | sprintf(master_name, "/dev/pty%c%c", *p1, *p2); |
d6fa1947 |
293 | pty->master_fd = open(master_name, O_RDWR); |
294 | if (pty->master_fd >= 0) { |
95c47834 |
295 | if (geteuid() == 0 || |
270d2e8d |
296 | access(master_name, R_OK | W_OK) == 0) { |
297 | /* |
298 | * We must also check at this point that we are |
299 | * able to open the slave side of the pty. We |
300 | * wouldn't want to allocate the wrong master, |
301 | * get all the way down to forking, and _then_ |
302 | * find we're unable to open the slave. |
303 | */ |
d6fa1947 |
304 | strcpy(pty->name, master_name); |
305 | pty->name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */ |
270d2e8d |
306 | |
d6fa1947 |
307 | if (pty_open_slave(pty) >= 0 && |
308 | access(pty->name, R_OK | W_OK) == 0) |
270d2e8d |
309 | goto got_one; |
d6fa1947 |
310 | if (pty->slave_fd > 0) |
311 | close(pty->slave_fd); |
312 | pty->slave_fd = -1; |
270d2e8d |
313 | } |
d6fa1947 |
314 | close(pty->master_fd); |
be4f86de |
315 | } |
95c47834 |
316 | } |
be4f86de |
317 | |
95c47834 |
318 | /* If we get here, we couldn't get a tty at all. */ |
319 | fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n"); |
320 | exit(1); |
be4f86de |
321 | |
95c47834 |
322 | got_one: |
95c47834 |
323 | |
324 | /* We need to chown/chmod the /dev/ttyXX device. */ |
325 | gp = getgrnam("tty"); |
d6fa1947 |
326 | chown(pty->name, getuid(), gp ? gp->gr_gid : -1); |
327 | chmod(pty->name, 0600); |
be4f86de |
328 | #else |
d6fa1947 |
329 | pty->master_fd = open("/dev/ptmx", O_RDWR); |
054d8535 |
330 | |
d6fa1947 |
331 | if (pty->master_fd < 0) { |
054d8535 |
332 | perror("/dev/ptmx: open"); |
333 | exit(1); |
334 | } |
335 | |
d6fa1947 |
336 | if (grantpt(pty->master_fd) < 0) { |
054d8535 |
337 | perror("grantpt"); |
338 | exit(1); |
339 | } |
340 | |
d6fa1947 |
341 | if (unlockpt(pty->master_fd) < 0) { |
054d8535 |
342 | perror("unlockpt"); |
343 | exit(1); |
344 | } |
345 | |
d6fa1947 |
346 | pty->name[FILENAME_MAX-1] = '\0'; |
347 | strncpy(pty->name, ptsname(pty->master_fd), FILENAME_MAX-1); |
be4f86de |
348 | #endif |
d6fa1947 |
349 | |
350 | if (!ptys_by_fd) |
351 | ptys_by_fd = newtree234(pty_compare_by_fd); |
352 | add234(ptys_by_fd, pty); |
95c47834 |
353 | } |
054d8535 |
354 | |
95c47834 |
355 | /* |
356 | * Pre-initialisation. This is here to get around the fact that GTK |
357 | * doesn't like being run in setuid/setgid programs (probably |
358 | * sensibly). So before we initialise GTK - and therefore before we |
359 | * even process the command line - we check to see if we're running |
360 | * set[ug]id. If so, we open our pty master _now_, chown it as |
361 | * necessary, and drop privileges. We can always close it again |
362 | * later. If we're potentially going to be doing utmp as well, we |
363 | * also fork off a utmp helper process and communicate with it by |
364 | * means of a pipe; the utmp helper will keep privileges in order |
365 | * to clean up utmp when we exit (i.e. when its end of our pipe |
366 | * closes). |
367 | */ |
368 | void pty_pre_init(void) |
369 | { |
d6fa1947 |
370 | Pty pty; |
371 | |
d4e1d591 |
372 | #ifndef OMIT_UTMP |
95c47834 |
373 | pid_t pid; |
374 | int pipefd[2]; |
d4e1d591 |
375 | #endif |
95c47834 |
376 | |
d6fa1947 |
377 | pty = single_pty = snew(struct pty_tag); |
378 | |
0f33f9d1 |
379 | /* set the child signal handler straight away; it needs to be set |
380 | * before we ever fork. */ |
381 | putty_signal(SIGCHLD, sigchld_handler); |
d6fa1947 |
382 | pty->master_fd = pty->slave_fd = -1; |
383 | #ifndef OMIT_UTMP |
384 | pty_stamped_utmp = FALSE; |
385 | #endif |
95c47834 |
386 | |
387 | if (geteuid() != getuid() || getegid() != getgid()) { |
d6fa1947 |
388 | pty_open_master(pty); |
39baeaa4 |
389 | } |
390 | |
95c47834 |
391 | #ifndef OMIT_UTMP |
39baeaa4 |
392 | /* |
95c47834 |
393 | * Fork off the utmp helper. |
755a6d84 |
394 | */ |
95c47834 |
395 | if (pipe(pipefd) < 0) { |
396 | perror("pterm: pipe"); |
397 | exit(1); |
398 | } |
399 | pid = fork(); |
400 | if (pid < 0) { |
401 | perror("pterm: fork"); |
402 | exit(1); |
403 | } else if (pid == 0) { |
404 | char display[128], buffer[128]; |
405 | int dlen, ret; |
406 | |
407 | close(pipefd[1]); |
408 | /* |
409 | * Now sit here until we receive a display name from the |
410 | * other end of the pipe, and then stamp utmp. Unstamp utmp |
411 | * again, and exit, when the pipe closes. |
412 | */ |
413 | |
414 | dlen = 0; |
415 | while (1) { |
416 | |
417 | ret = read(pipefd[0], buffer, lenof(buffer)); |
418 | if (ret <= 0) { |
419 | cleanup_utmp(); |
0f33f9d1 |
420 | _exit(0); |
95c47834 |
421 | } else if (!pty_stamped_utmp) { |
422 | if (dlen < lenof(display)) |
423 | memcpy(display+dlen, buffer, |
424 | min(ret, lenof(display)-dlen)); |
425 | if (buffer[ret-1] == '\0') { |
426 | /* |
427 | * Now we have a display name. NUL-terminate |
428 | * it, and stamp utmp. |
429 | */ |
430 | display[lenof(display)-1] = '\0'; |
431 | /* |
432 | * Trap as many fatal signals as we can in the |
433 | * hope of having the best possible chance to |
434 | * clean up utmp before termination. We are |
435 | * unfortunately unprotected against SIGKILL, |
436 | * but that's life. |
437 | */ |
0f33f9d1 |
438 | putty_signal(SIGHUP, fatal_sig_handler); |
439 | putty_signal(SIGINT, fatal_sig_handler); |
440 | putty_signal(SIGQUIT, fatal_sig_handler); |
441 | putty_signal(SIGILL, fatal_sig_handler); |
442 | putty_signal(SIGABRT, fatal_sig_handler); |
443 | putty_signal(SIGFPE, fatal_sig_handler); |
444 | putty_signal(SIGPIPE, fatal_sig_handler); |
445 | putty_signal(SIGALRM, fatal_sig_handler); |
446 | putty_signal(SIGTERM, fatal_sig_handler); |
447 | putty_signal(SIGSEGV, fatal_sig_handler); |
448 | putty_signal(SIGUSR1, fatal_sig_handler); |
449 | putty_signal(SIGUSR2, fatal_sig_handler); |
755a6d84 |
450 | #ifdef SIGBUS |
0f33f9d1 |
451 | putty_signal(SIGBUS, fatal_sig_handler); |
755a6d84 |
452 | #endif |
453 | #ifdef SIGPOLL |
0f33f9d1 |
454 | putty_signal(SIGPOLL, fatal_sig_handler); |
755a6d84 |
455 | #endif |
456 | #ifdef SIGPROF |
0f33f9d1 |
457 | putty_signal(SIGPROF, fatal_sig_handler); |
755a6d84 |
458 | #endif |
459 | #ifdef SIGSYS |
0f33f9d1 |
460 | putty_signal(SIGSYS, fatal_sig_handler); |
755a6d84 |
461 | #endif |
462 | #ifdef SIGTRAP |
0f33f9d1 |
463 | putty_signal(SIGTRAP, fatal_sig_handler); |
755a6d84 |
464 | #endif |
465 | #ifdef SIGVTALRM |
0f33f9d1 |
466 | putty_signal(SIGVTALRM, fatal_sig_handler); |
755a6d84 |
467 | #endif |
468 | #ifdef SIGXCPU |
0f33f9d1 |
469 | putty_signal(SIGXCPU, fatal_sig_handler); |
755a6d84 |
470 | #endif |
471 | #ifdef SIGXFSZ |
0f33f9d1 |
472 | putty_signal(SIGXFSZ, fatal_sig_handler); |
755a6d84 |
473 | #endif |
474 | #ifdef SIGIO |
0f33f9d1 |
475 | putty_signal(SIGIO, fatal_sig_handler); |
95c47834 |
476 | #endif |
d6fa1947 |
477 | setup_utmp(pty->name, display); |
95c47834 |
478 | } |
479 | } |
480 | } |
481 | } else { |
482 | close(pipefd[0]); |
483 | pty_utmp_helper_pid = pid; |
484 | pty_utmp_helper_pipe = pipefd[1]; |
485 | } |
755a6d84 |
486 | #endif |
95c47834 |
487 | |
488 | /* Drop privs. */ |
489 | { |
95c47834 |
490 | #ifndef HAVE_NO_SETRESUID |
d4e1d591 |
491 | int gid = getgid(), uid = getuid(); |
95c47834 |
492 | int setresgid(gid_t, gid_t, gid_t); |
493 | int setresuid(uid_t, uid_t, uid_t); |
494 | setresgid(gid, gid, gid); |
495 | setresuid(uid, uid, uid); |
496 | #else |
497 | setgid(getgid()); |
498 | setuid(getuid()); |
499 | #endif |
500 | } |
501 | } |
502 | |
d6fa1947 |
503 | int pty_real_select_result(Pty pty, int event, int status) |
74aca06d |
504 | { |
505 | char buf[4096]; |
506 | int ret; |
507 | int finished = FALSE; |
508 | |
d6fa1947 |
509 | if (event < 0) { |
74aca06d |
510 | /* |
d6fa1947 |
511 | * We've been called because our child process did |
512 | * something. `status' tells us what. |
74aca06d |
513 | */ |
d6fa1947 |
514 | if ((WIFEXITED(status) || WIFSIGNALED(status))) { |
74aca06d |
515 | /* |
d6fa1947 |
516 | * The primary child process died. We could keep |
517 | * the terminal open for remaining subprocesses to |
518 | * output to, but conventional wisdom seems to feel |
519 | * that that's the Wrong Thing for an xterm-alike, |
520 | * so we bail out now (though we don't necessarily |
521 | * _close_ the window, depending on the state of |
522 | * Close On Exit). This would be easy enough to |
523 | * change or make configurable if necessary. |
74aca06d |
524 | */ |
d6fa1947 |
525 | pty->exit_code = status; |
526 | pty->child_dead = TRUE; |
527 | del234(ptys_by_pid, pty); |
74aca06d |
528 | finished = TRUE; |
74aca06d |
529 | } |
d6fa1947 |
530 | } else { |
531 | if (event == 1) { |
74aca06d |
532 | |
d6fa1947 |
533 | ret = read(pty->master_fd, buf, sizeof(buf)); |
74aca06d |
534 | |
d6fa1947 |
535 | /* |
536 | * Clean termination condition is that either ret == 0, or ret |
537 | * < 0 and errno == EIO. Not sure why the latter, but it seems |
538 | * to happen. Boo. |
539 | */ |
540 | if (ret == 0 || (ret < 0 && errno == EIO)) { |
74aca06d |
541 | /* |
d6fa1947 |
542 | * We assume a clean exit if the pty has closed but the |
543 | * actual child process hasn't. The only way I can |
544 | * imagine this happening is if it detaches itself from |
545 | * the pty and goes daemonic - in which case the |
546 | * expected usage model would precisely _not_ be for |
547 | * the pterm window to hang around! |
74aca06d |
548 | */ |
74aca06d |
549 | finished = TRUE; |
d6fa1947 |
550 | if (!pty->child_dead) |
551 | pty->exit_code = 0; |
552 | } else if (ret < 0) { |
553 | perror("read pty master"); |
554 | exit(1); |
555 | } else if (ret > 0) { |
556 | from_backend(pty->frontend, 0, buf, ret); |
74aca06d |
557 | } |
d6fa1947 |
558 | } |
74aca06d |
559 | } |
560 | |
d6fa1947 |
561 | if (finished && !pty->finished) { |
562 | uxsel_del(pty->master_fd); |
563 | pty_close(pty); |
564 | pty->master_fd = -1; |
74aca06d |
565 | |
d6fa1947 |
566 | pty->finished = TRUE; |
74aca06d |
567 | |
568 | /* |
569 | * This is a slight layering-violation sort of hack: only |
570 | * if we're not closing on exit (COE is set to Never, or to |
571 | * Only On Clean and it wasn't a clean exit) do we output a |
572 | * `terminated' message. |
573 | */ |
d6fa1947 |
574 | if (pty->cfg.close_on_exit == FORCE_OFF || |
575 | (pty->cfg.close_on_exit == AUTO && pty->exit_code != 0)) { |
74aca06d |
576 | char message[512]; |
d6fa1947 |
577 | if (WIFEXITED(pty->exit_code)) |
74aca06d |
578 | sprintf(message, "\r\n[pterm: process terminated with exit" |
d6fa1947 |
579 | " code %d]\r\n", WEXITSTATUS(pty->exit_code)); |
580 | else if (WIFSIGNALED(pty->exit_code)) |
74aca06d |
581 | #ifdef HAVE_NO_STRSIGNAL |
582 | sprintf(message, "\r\n[pterm: process terminated on signal" |
d6fa1947 |
583 | " %d]\r\n", WTERMSIG(pty->exit_code)); |
74aca06d |
584 | #else |
585 | sprintf(message, "\r\n[pterm: process terminated on signal" |
d6fa1947 |
586 | " %d (%.400s)]\r\n", WTERMSIG(pty->exit_code), |
587 | strsignal(WTERMSIG(pty->exit_code))); |
74aca06d |
588 | #endif |
d6fa1947 |
589 | from_backend(pty->frontend, 0, message, strlen(message)); |
74aca06d |
590 | } |
39934deb |
591 | |
d6fa1947 |
592 | notify_remote_exit(pty->frontend); |
74aca06d |
593 | } |
d6fa1947 |
594 | |
74aca06d |
595 | return !finished; |
596 | } |
597 | |
d6fa1947 |
598 | int pty_select_result(int fd, int event) |
74aca06d |
599 | { |
d6fa1947 |
600 | int ret = TRUE; |
601 | Pty pty; |
602 | |
603 | if (fd == pty_signal_pipe[0]) { |
604 | pid_t pid; |
605 | int ipid; |
606 | int status; |
607 | char c[1]; |
608 | |
609 | read(pty_signal_pipe[0], c, 1); /* ignore its value; it'll be `x' */ |
610 | |
611 | do { |
612 | pid = waitpid(-1, &status, WNOHANG); |
613 | |
614 | ipid = pid; |
615 | pty = find234(ptys_by_pid, &pid, pty_find_by_pid); |
616 | |
617 | if (pty) |
618 | ret = ret && pty_real_select_result(pty, -1, status); |
619 | } while (pid > 0); |
620 | } else { |
621 | pty = find234(ptys_by_fd, &fd, pty_find_by_fd); |
622 | |
623 | if (pty) |
624 | ret = ret && pty_real_select_result(pty, event, 0); |
625 | } |
626 | |
627 | return ret; |
628 | } |
629 | |
630 | static void pty_uxsel_setup(Pty pty) |
631 | { |
632 | uxsel_set(pty->master_fd, 1, pty_select_result); |
633 | |
634 | /* |
635 | * In principle this only needs calling once for all pty |
636 | * backend instances, but it's simplest just to call it every |
637 | * time; uxsel won't mind. |
638 | */ |
74aca06d |
639 | uxsel_set(pty_signal_pipe[0], 1, pty_select_result); |
640 | } |
641 | |
95c47834 |
642 | /* |
643 | * Called to set up the pty. |
644 | * |
645 | * Returns an error message, or NULL on success. |
646 | * |
647 | * Also places the canonical host name into `realhost'. It must be |
648 | * freed by the caller. |
649 | */ |
cbe2d68f |
650 | static const char *pty_init(void *frontend, void **backend_handle, Config *cfg, |
79bf227b |
651 | char *host, int port, char **realhost, int nodelay, |
652 | int keepalive) |
95c47834 |
653 | { |
654 | int slavefd; |
655 | pid_t pid, pgrp; |
c13772b1 |
656 | #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */ |
7af753e6 |
657 | long windowid; |
c13772b1 |
658 | #endif |
d6fa1947 |
659 | Pty pty; |
95c47834 |
660 | |
d6fa1947 |
661 | if (single_pty) { |
662 | pty = single_pty; |
663 | } else { |
664 | pty = snew(struct pty_tag); |
665 | pty->master_fd = pty->slave_fd = -1; |
666 | #ifndef OMIT_UTMP |
667 | pty_stamped_utmp = FALSE; |
668 | #endif |
669 | } |
670 | |
671 | pty->frontend = frontend; |
28d00fe4 |
672 | *backend_handle = NULL; /* we can't sensibly use this, sadly */ |
673 | |
d6fa1947 |
674 | pty->cfg = *cfg; /* structure copy */ |
675 | pty->term_width = cfg->width; |
676 | pty->term_height = cfg->height; |
f278d6f8 |
677 | |
d6fa1947 |
678 | if (pty->master_fd < 0) |
679 | pty_open_master(pty); |
95c47834 |
680 | |
681 | /* |
682 | * Set the backspace character to be whichever of ^H and ^? is |
683 | * specified by bksp_is_delete. |
684 | */ |
685 | { |
686 | struct termios attrs; |
d6fa1947 |
687 | tcgetattr(pty->master_fd, &attrs); |
86916870 |
688 | attrs.c_cc[VERASE] = cfg->bksp_is_delete ? '\177' : '\010'; |
d6fa1947 |
689 | tcsetattr(pty->master_fd, TCSANOW, &attrs); |
95c47834 |
690 | } |
691 | |
d4e1d591 |
692 | #ifndef OMIT_UTMP |
95c47834 |
693 | /* |
694 | * Stamp utmp (that is, tell the utmp helper process to do so), |
695 | * or not. |
696 | */ |
58dcb876 |
697 | if (!cfg->stamp_utmp) { |
95c47834 |
698 | close(pty_utmp_helper_pipe); /* just let the child process die */ |
58dcb876 |
699 | pty_utmp_helper_pipe = -1; |
700 | } else { |
d6fa1947 |
701 | char *location = get_x_display(pty->frontend); |
95c47834 |
702 | int len = strlen(location)+1, pos = 0; /* +1 to include NUL */ |
703 | while (pos < len) { |
704 | int ret = write(pty_utmp_helper_pipe, location+pos, len - pos); |
705 | if (ret < 0) { |
706 | perror("pterm: writing to utmp helper process"); |
707 | close(pty_utmp_helper_pipe); /* arrgh, just give up */ |
58dcb876 |
708 | pty_utmp_helper_pipe = -1; |
95c47834 |
709 | break; |
710 | } |
711 | pos += ret; |
712 | } |
713 | } |
d4e1d591 |
714 | #endif |
755a6d84 |
715 | |
c13772b1 |
716 | #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */ |
d6fa1947 |
717 | windowid = get_windowid(pty->frontend); |
c13772b1 |
718 | #endif |
7af753e6 |
719 | |
755a6d84 |
720 | /* |
054d8535 |
721 | * Fork and execute the command. |
722 | */ |
723 | pid = fork(); |
724 | if (pid < 0) { |
725 | perror("fork"); |
88e6b9ca |
726 | exit(1); |
054d8535 |
727 | } |
728 | |
729 | if (pid == 0) { |
730 | int i; |
731 | /* |
732 | * We are the child. |
733 | */ |
d37c2d81 |
734 | |
d6fa1947 |
735 | slavefd = pty_open_slave(pty); |
d37c2d81 |
736 | if (slavefd < 0) { |
737 | perror("slave pty: open"); |
0f33f9d1 |
738 | _exit(1); |
d37c2d81 |
739 | } |
740 | |
d6fa1947 |
741 | close(pty->master_fd); |
054d8535 |
742 | fcntl(slavefd, F_SETFD, 0); /* don't close on exec */ |
743 | dup2(slavefd, 0); |
744 | dup2(slavefd, 1); |
745 | dup2(slavefd, 2); |
746 | setsid(); |
bbaa7993 |
747 | #ifdef TIOCSCTTY |
d37c2d81 |
748 | ioctl(slavefd, TIOCSCTTY, 1); |
bbaa7993 |
749 | #endif |
d37c2d81 |
750 | pgrp = getpid(); |
751 | tcsetpgrp(slavefd, pgrp); |
ea0716c6 |
752 | setpgid(pgrp, pgrp); |
d6fa1947 |
753 | close(open(pty->name, O_WRONLY, 0)); |
ea0716c6 |
754 | setpgid(pgrp, pgrp); |
054d8535 |
755 | /* Close everything _else_, for tidiness. */ |
756 | for (i = 3; i < 1024; i++) |
757 | close(i); |
fe9548aa |
758 | { |
30d1257c |
759 | char *term_env_var = dupprintf("TERM=%s", cfg->termtype); |
fe9548aa |
760 | putenv(term_env_var); |
30d1257c |
761 | /* We mustn't free term_env_var, as putenv links it into the |
762 | * environment in place. |
763 | */ |
fe9548aa |
764 | } |
c13772b1 |
765 | #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */ |
7af753e6 |
766 | { |
30d1257c |
767 | char *windowid_env_var = dupprintf("WINDOWID=%ld", windowid); |
7af753e6 |
768 | putenv(windowid_env_var); |
30d1257c |
769 | /* We mustn't free windowid_env_var, as putenv links it into the |
770 | * environment in place. |
771 | */ |
7af753e6 |
772 | } |
c13772b1 |
773 | #endif |
73feed4f |
774 | { |
775 | char *e = cfg->environmt; |
776 | char *var, *varend, *val, *varval; |
777 | while (*e) { |
778 | var = e; |
779 | while (*e && *e != '\t') e++; |
780 | varend = e; |
781 | if (*e == '\t') e++; |
782 | val = e; |
783 | while (*e) e++; |
784 | e++; |
785 | |
786 | varval = dupprintf("%.*s=%s", varend-var, var, val); |
787 | putenv(varval); |
788 | /* |
789 | * We must not free varval, since putenv links it |
790 | * into the environment _in place_. Weird, but |
791 | * there we go. Memory usage will be rationalised |
792 | * as soon as we exec anyway. |
793 | */ |
794 | } |
795 | } |
796 | |
8bf5c419 |
797 | /* |
798 | * SIGINT and SIGQUIT may have been set to ignored by our |
799 | * parent, particularly by things like sh -c 'pterm &' and |
15b5d988 |
800 | * some window managers. SIGCHLD, meanwhile, was blocked |
801 | * during pt_main() startup. Reverse all this for our child |
802 | * process. |
8bf5c419 |
803 | */ |
0f33f9d1 |
804 | putty_signal(SIGINT, SIG_DFL); |
805 | putty_signal(SIGQUIT, SIG_DFL); |
15b5d988 |
806 | block_signal(SIGCHLD, 0); |
6169c758 |
807 | if (pty_argv) |
808 | execvp(pty_argv[0], pty_argv); |
c8ee61b9 |
809 | else { |
810 | char *shell = getenv("SHELL"); |
811 | char *shellname; |
86916870 |
812 | if (cfg->login_shell) { |
c8ee61b9 |
813 | char *p = strrchr(shell, '/'); |
3d88e64d |
814 | shellname = snewn(2+strlen(shell), char); |
c8ee61b9 |
815 | p = p ? p+1 : shell; |
816 | sprintf(shellname, "-%s", p); |
817 | } else |
818 | shellname = shell; |
30264db9 |
819 | execl(getenv("SHELL"), shellname, (void *)NULL); |
c8ee61b9 |
820 | } |
821 | |
054d8535 |
822 | /* |
823 | * If we're here, exec has gone badly foom. |
824 | */ |
825 | perror("exec"); |
0f33f9d1 |
826 | _exit(127); |
054d8535 |
827 | } else { |
d6fa1947 |
828 | pty->child_pid = pid; |
829 | pty->child_dead = FALSE; |
830 | pty->finished = FALSE; |
831 | if (pty->slave_fd > 0) |
832 | close(pty->slave_fd); |
833 | if (!ptys_by_pid) |
834 | ptys_by_pid = newtree234(pty_compare_by_pid); |
835 | add234(ptys_by_pid, pty); |
270d2e8d |
836 | } |
054d8535 |
837 | |
d6fa1947 |
838 | if (pty_signal_pipe[0] < 0 && pipe(pty_signal_pipe) < 0) { |
74aca06d |
839 | perror("pipe"); |
840 | exit(1); |
841 | } |
d6fa1947 |
842 | pty_uxsel_setup(pty); |
843 | |
844 | *backend_handle = pty; |
74aca06d |
845 | |
1709795f |
846 | return NULL; |
847 | } |
848 | |
86916870 |
849 | static void pty_reconfig(void *handle, Config *cfg) |
850 | { |
d6fa1947 |
851 | Pty pty = (Pty)handle; |
6b0eeb4e |
852 | /* |
853 | * We don't have much need to reconfigure this backend, but |
854 | * unfortunately we do need to pick up the setting of Close On |
855 | * Exit so we know whether to give a `terminated' message. |
856 | */ |
d6fa1947 |
857 | pty->cfg = *cfg; /* structure copy */ |
86916870 |
858 | } |
859 | |
860 | /* |
6b0eeb4e |
861 | * Stub routine (never called in pterm). |
cb60dcb3 |
862 | */ |
863 | static void pty_free(void *handle) |
864 | { |
d6fa1947 |
865 | Pty pty = (Pty)handle; |
866 | |
867 | /* Either of these may fail `not found'. That's fine with us. */ |
868 | del234(ptys_by_pid, pty); |
869 | del234(ptys_by_fd, pty); |
870 | |
871 | sfree(pty); |
cb60dcb3 |
872 | } |
873 | |
cb60dcb3 |
874 | /* |
1709795f |
875 | * Called to send data down the pty. |
876 | */ |
28d00fe4 |
877 | static int pty_send(void *handle, char *buf, int len) |
1709795f |
878 | { |
d6fa1947 |
879 | Pty pty = (Pty)handle; |
880 | |
881 | if (pty->master_fd < 0) |
90cfd8f4 |
882 | return 0; /* ignore all writes if fd closed */ |
883 | |
054d8535 |
884 | while (len > 0) { |
d6fa1947 |
885 | int ret = write(pty->master_fd, buf, len); |
054d8535 |
886 | if (ret < 0) { |
887 | perror("write pty master"); |
888 | exit(1); |
889 | } |
890 | buf += ret; |
891 | len -= ret; |
892 | } |
1709795f |
893 | return 0; |
894 | } |
895 | |
d6fa1947 |
896 | static void pty_close(Pty pty) |
90cfd8f4 |
897 | { |
d6fa1947 |
898 | if (pty->master_fd >= 0) { |
899 | close(pty->master_fd); |
900 | pty->master_fd = -1; |
90cfd8f4 |
901 | } |
d4e1d591 |
902 | #ifndef OMIT_UTMP |
58dcb876 |
903 | if (pty_utmp_helper_pipe >= 0) { |
904 | close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */ |
905 | pty_utmp_helper_pipe = -1; |
906 | } |
d4e1d591 |
907 | #endif |
90cfd8f4 |
908 | } |
909 | |
1709795f |
910 | /* |
911 | * Called to query the current socket sendability status. |
912 | */ |
28d00fe4 |
913 | static int pty_sendbuffer(void *handle) |
1709795f |
914 | { |
d6fa1947 |
915 | /* Pty pty = (Pty)handle; */ |
1709795f |
916 | return 0; |
917 | } |
918 | |
919 | /* |
920 | * Called to set the size of the window |
921 | */ |
28d00fe4 |
922 | static void pty_size(void *handle, int width, int height) |
1709795f |
923 | { |
d6fa1947 |
924 | Pty pty = (Pty)handle; |
88e6b9ca |
925 | struct winsize size; |
926 | |
d6fa1947 |
927 | pty->term_width = width; |
928 | pty->term_height = height; |
f278d6f8 |
929 | |
d6fa1947 |
930 | size.ws_row = (unsigned short)pty->term_height; |
931 | size.ws_col = (unsigned short)pty->term_width; |
932 | size.ws_xpixel = (unsigned short) pty->term_width * |
933 | font_dimension(pty->frontend, 0); |
934 | size.ws_ypixel = (unsigned short) pty->term_height * |
935 | font_dimension(pty->frontend, 1); |
936 | ioctl(pty->master_fd, TIOCSWINSZ, (void *)&size); |
1709795f |
937 | return; |
938 | } |
939 | |
940 | /* |
941 | * Send special codes. |
942 | */ |
28d00fe4 |
943 | static void pty_special(void *handle, Telnet_Special code) |
1709795f |
944 | { |
d6fa1947 |
945 | /* Pty pty = (Pty)handle; */ |
1709795f |
946 | /* Do nothing! */ |
947 | return; |
948 | } |
949 | |
125105d1 |
950 | /* |
951 | * Return a list of the special codes that make sense in this |
952 | * protocol. |
953 | */ |
954 | static const struct telnet_special *pty_get_specials(void *handle) |
955 | { |
d6fa1947 |
956 | /* Pty pty = (Pty)handle; */ |
125105d1 |
957 | /* |
958 | * Hmm. When I get round to having this actually usable, it |
959 | * might be quite nice to have the ability to deliver a few |
960 | * well chosen signals to the child process - SIGINT, SIGTERM, |
961 | * SIGKILL at least. |
962 | */ |
963 | return NULL; |
964 | } |
965 | |
28d00fe4 |
966 | static Socket pty_socket(void *handle) |
1709795f |
967 | { |
d6fa1947 |
968 | /* Pty pty = (Pty)handle; */ |
1709795f |
969 | return NULL; /* shouldn't ever be needed */ |
970 | } |
971 | |
28d00fe4 |
972 | static int pty_sendok(void *handle) |
1709795f |
973 | { |
d6fa1947 |
974 | /* Pty pty = (Pty)handle; */ |
1709795f |
975 | return 1; |
976 | } |
977 | |
28d00fe4 |
978 | static void pty_unthrottle(void *handle, int backlog) |
1709795f |
979 | { |
d6fa1947 |
980 | /* Pty pty = (Pty)handle; */ |
1709795f |
981 | /* do nothing */ |
982 | } |
983 | |
28d00fe4 |
984 | static int pty_ldisc(void *handle, int option) |
1709795f |
985 | { |
d6fa1947 |
986 | /* Pty pty = (Pty)handle; */ |
1709795f |
987 | return 0; /* neither editing nor echoing */ |
988 | } |
989 | |
b9d7bcad |
990 | static void pty_provide_ldisc(void *handle, void *ldisc) |
991 | { |
d6fa1947 |
992 | /* Pty pty = (Pty)handle; */ |
b9d7bcad |
993 | /* This is a stub. */ |
994 | } |
995 | |
a8327734 |
996 | static void pty_provide_logctx(void *handle, void *logctx) |
997 | { |
d6fa1947 |
998 | /* Pty pty = (Pty)handle; */ |
a8327734 |
999 | /* This is a stub. */ |
1000 | } |
1001 | |
28d00fe4 |
1002 | static int pty_exitcode(void *handle) |
1709795f |
1003 | { |
d6fa1947 |
1004 | Pty pty = (Pty)handle; |
1005 | if (!pty->finished) |
90cfd8f4 |
1006 | return -1; /* not dead yet */ |
1007 | else |
d6fa1947 |
1008 | return pty->exit_code; |
1709795f |
1009 | } |
1010 | |
f89c3294 |
1011 | static int pty_cfg_info(void *handle) |
1012 | { |
d6fa1947 |
1013 | /* Pty pty = (Pty)handle; */ |
f89c3294 |
1014 | return 0; |
1015 | } |
1016 | |
1709795f |
1017 | Backend pty_backend = { |
1018 | pty_init, |
cb60dcb3 |
1019 | pty_free, |
86916870 |
1020 | pty_reconfig, |
1709795f |
1021 | pty_send, |
1022 | pty_sendbuffer, |
1023 | pty_size, |
1024 | pty_special, |
125105d1 |
1025 | pty_get_specials, |
1709795f |
1026 | pty_socket, |
1027 | pty_exitcode, |
1028 | pty_sendok, |
1029 | pty_ldisc, |
b9d7bcad |
1030 | pty_provide_ldisc, |
a8327734 |
1031 | pty_provide_logctx, |
1709795f |
1032 | pty_unthrottle, |
f89c3294 |
1033 | pty_cfg_info, |
1709795f |
1034 | 1 |
1035 | }; |