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> |
2916fa14 |
12 | #include <assert.h> |
054d8535 |
13 | #include <fcntl.h> |
88e6b9ca |
14 | #include <termios.h> |
be4f86de |
15 | #include <grp.h> |
755a6d84 |
16 | #include <utmp.h> |
17 | #include <pwd.h> |
18 | #include <time.h> |
a0e16eb1 |
19 | #include <sys/types.h> |
d4e1d591 |
20 | #include <sys/stat.h> |
a0e16eb1 |
21 | #include <sys/wait.h> |
88e6b9ca |
22 | #include <sys/ioctl.h> |
0f33f9d1 |
23 | #include <errno.h> |
1709795f |
24 | |
25 | #include "putty.h" |
d6fa1947 |
26 | #include "tree234.h" |
1709795f |
27 | |
0b1df797 |
28 | #ifndef OMIT_UTMP |
bea25c48 |
29 | #include <utmpx.h> |
30 | #endif |
31 | |
1709795f |
32 | #ifndef FALSE |
33 | #define FALSE 0 |
34 | #endif |
35 | #ifndef TRUE |
36 | #define TRUE 1 |
37 | #endif |
38 | |
bea25c48 |
39 | /* updwtmpx() needs the name of the wtmp file. Try to find it. */ |
40 | #ifndef WTMPX_FILE |
41 | #ifdef _PATH_WTMPX |
42 | #define WTMPX_FILE _PATH_WTMPX |
43 | #else |
44 | #define WTMPX_FILE "/var/log/wtmpx" |
755a6d84 |
45 | #endif |
755a6d84 |
46 | #endif |
bea25c48 |
47 | |
755a6d84 |
48 | #ifndef LASTLOG_FILE |
49 | #ifdef _PATH_LASTLOG |
50 | #define LASTLOG_FILE _PATH_LASTLOG |
51 | #else |
52 | #define LASTLOG_FILE "/var/log/lastlog" |
53 | #endif |
54 | #endif |
55 | |
f51dc031 |
56 | /* |
57 | * Set up a default for vaguely sane systems. The idea is that if |
58 | * OMIT_UTMP is not defined, then at least one of the symbols which |
59 | * enable particular forms of utmp processing should be, if only so |
60 | * that a link error can warn you that you should have defined |
61 | * OMIT_UTMP if you didn't want any. Currently HAVE_PUTUTLINE is |
62 | * the only such symbol. |
63 | */ |
64 | #ifndef OMIT_UTMP |
65 | #if !defined HAVE_PUTUTLINE |
66 | #define HAVE_PUTUTLINE |
67 | #endif |
68 | #endif |
69 | |
d6fa1947 |
70 | typedef struct pty_tag *Pty; |
71 | |
72 | /* |
73 | * The pty_signal_pipe, along with the SIGCHLD handler, must be |
74 | * process-global rather than session-specific. |
75 | */ |
76 | static int pty_signal_pipe[2] = { -1, -1 }; /* obviously bogus initial val */ |
77 | |
78 | struct pty_tag { |
79 | Config cfg; |
80 | int master_fd, slave_fd; |
81 | void *frontend; |
82 | char name[FILENAME_MAX]; |
83 | int child_pid; |
84 | int term_width, term_height; |
85 | int child_dead, finished; |
86 | int exit_code; |
2916fa14 |
87 | bufchain output_data; |
d6fa1947 |
88 | }; |
89 | |
90 | /* |
91 | * We store our pty backends in a tree sorted by master fd, so that |
92 | * when we get an uxsel notification we know which backend instance |
93 | * is the owner of the pty that caused it. |
94 | */ |
95 | static int pty_compare_by_fd(void *av, void *bv) |
96 | { |
97 | Pty a = (Pty)av; |
98 | Pty b = (Pty)bv; |
99 | |
100 | if (a->master_fd < b->master_fd) |
101 | return -1; |
102 | else if (a->master_fd > b->master_fd) |
103 | return +1; |
104 | return 0; |
105 | } |
106 | |
107 | static int pty_find_by_fd(void *av, void *bv) |
108 | { |
109 | int a = *(int *)av; |
110 | Pty b = (Pty)bv; |
111 | |
112 | if (a < b->master_fd) |
113 | return -1; |
114 | else if (a > b->master_fd) |
115 | return +1; |
116 | return 0; |
117 | } |
054d8535 |
118 | |
d6fa1947 |
119 | static tree234 *ptys_by_fd = NULL; |
120 | |
121 | /* |
122 | * We also have a tree sorted by child pid, so that when we wait() |
123 | * in response to the signal we know which backend instance is the |
124 | * owner of the process that caused the signal. |
125 | */ |
126 | static int pty_compare_by_pid(void *av, void *bv) |
127 | { |
128 | Pty a = (Pty)av; |
129 | Pty b = (Pty)bv; |
130 | |
131 | if (a->child_pid < b->child_pid) |
132 | return -1; |
133 | else if (a->child_pid > b->child_pid) |
134 | return +1; |
135 | return 0; |
136 | } |
137 | |
138 | static int pty_find_by_pid(void *av, void *bv) |
139 | { |
140 | int a = *(int *)av; |
141 | Pty b = (Pty)bv; |
142 | |
143 | if (a < b->child_pid) |
144 | return -1; |
145 | else if (a > b->child_pid) |
146 | return +1; |
147 | return 0; |
148 | } |
149 | |
150 | static tree234 *ptys_by_pid = NULL; |
151 | |
152 | /* |
153 | * If we are using pty_pre_init(), it will need to have already |
154 | * allocated a pty structure, which we must then return from |
155 | * pty_init() rather than allocating a new one. Here we store that |
156 | * structure between allocation and use. |
157 | * |
158 | * Note that although most of this module is entirely capable of |
159 | * handling multiple ptys in a single process, pty_pre_init() is |
160 | * fundamentally _dependent_ on there being at most one pty per |
161 | * process, so the normal static-data constraints don't apply. |
162 | * |
163 | * Likewise, since utmp is only used via pty_pre_init, it too must |
164 | * be single-instance, so we can declare utmp-related variables |
165 | * here. |
166 | */ |
167 | static Pty single_pty = NULL; |
74aca06d |
168 | |
d4e1d591 |
169 | #ifndef OMIT_UTMP |
170 | static int pty_utmp_helper_pid, pty_utmp_helper_pipe; |
d6fa1947 |
171 | static int pty_stamped_utmp; |
bea25c48 |
172 | static struct utmpx utmp_entry; |
d6fa1947 |
173 | #endif |
174 | |
175 | /* |
176 | * pty_argv is a grievous hack to allow a proper argv to be passed |
177 | * through from the Unix command line. Again, it doesn't really |
178 | * make sense outside a one-pty-per-process setup. |
179 | */ |
180 | char **pty_argv; |
d6fa1947 |
181 | |
182 | static void pty_close(Pty pty); |
2916fa14 |
183 | static void pty_try_write(Pty pty); |
d4e1d591 |
184 | |
d6fa1947 |
185 | #ifndef OMIT_UTMP |
95c47834 |
186 | static void setup_utmp(char *ttyname, char *location) |
755a6d84 |
187 | { |
755a6d84 |
188 | #ifdef HAVE_LASTLOG |
189 | struct lastlog lastlog_entry; |
190 | FILE *lastlog; |
191 | #endif |
192 | struct passwd *pw; |
bea25c48 |
193 | struct timeval tv; |
755a6d84 |
194 | |
195 | pw = getpwuid(getuid()); |
196 | memset(&utmp_entry, 0, sizeof(utmp_entry)); |
197 | utmp_entry.ut_type = USER_PROCESS; |
198 | utmp_entry.ut_pid = getpid(); |
199 | strncpy(utmp_entry.ut_line, ttyname+5, lenof(utmp_entry.ut_line)); |
200 | strncpy(utmp_entry.ut_id, ttyname+8, lenof(utmp_entry.ut_id)); |
201 | strncpy(utmp_entry.ut_user, pw->pw_name, lenof(utmp_entry.ut_user)); |
202 | strncpy(utmp_entry.ut_host, location, lenof(utmp_entry.ut_host)); |
bea25c48 |
203 | /* |
204 | * Apparently there are some architectures where (struct |
205 | * utmpx).ut_tv is not essentially struct timeval (e.g. Linux |
206 | * amd64). Hence the temporary. |
207 | */ |
208 | gettimeofday(&tv, NULL); |
209 | utmp_entry.ut_tv.tv_sec = tv.tv_sec; |
210 | utmp_entry.ut_tv.tv_usec = tv.tv_usec; |
755a6d84 |
211 | |
bea25c48 |
212 | setutxent(); |
213 | pututxline(&utmp_entry); |
214 | endutxent(); |
215 | |
216 | updwtmpx(WTMPX_FILE, &utmp_entry); |
755a6d84 |
217 | |
218 | #ifdef HAVE_LASTLOG |
219 | memset(&lastlog_entry, 0, sizeof(lastlog_entry)); |
220 | strncpy(lastlog_entry.ll_line, ttyname+5, lenof(lastlog_entry.ll_line)); |
221 | strncpy(lastlog_entry.ll_host, location, lenof(lastlog_entry.ll_host)); |
222 | time(&lastlog_entry.ll_time); |
223 | if ((lastlog = fopen(LASTLOG_FILE, "r+")) != NULL) { |
224 | fseek(lastlog, sizeof(lastlog_entry) * getuid(), SEEK_SET); |
225 | fwrite(&lastlog_entry, 1, sizeof(lastlog_entry), lastlog); |
226 | fclose(lastlog); |
227 | } |
228 | #endif |
229 | |
f51dc031 |
230 | pty_stamped_utmp = 1; |
231 | |
755a6d84 |
232 | } |
233 | |
234 | static void cleanup_utmp(void) |
235 | { |
bea25c48 |
236 | struct timeval tv; |
755a6d84 |
237 | |
95c47834 |
238 | if (!pty_stamped_utmp) |
f51dc031 |
239 | return; |
240 | |
755a6d84 |
241 | utmp_entry.ut_type = DEAD_PROCESS; |
242 | memset(utmp_entry.ut_user, 0, lenof(utmp_entry.ut_user)); |
bea25c48 |
243 | gettimeofday(&tv, NULL); |
244 | utmp_entry.ut_tv.tv_sec = tv.tv_sec; |
245 | utmp_entry.ut_tv.tv_usec = tv.tv_usec; |
755a6d84 |
246 | |
bea25c48 |
247 | updwtmpx(WTMPX_FILE, &utmp_entry); |
755a6d84 |
248 | |
249 | memset(utmp_entry.ut_line, 0, lenof(utmp_entry.ut_line)); |
bea25c48 |
250 | utmp_entry.ut_tv.tv_sec = 0; |
251 | utmp_entry.ut_tv.tv_usec = 0; |
755a6d84 |
252 | |
bea25c48 |
253 | setutxent(); |
254 | pututxline(&utmp_entry); |
255 | endutxent(); |
755a6d84 |
256 | |
f51dc031 |
257 | pty_stamped_utmp = 0; /* ensure we never double-cleanup */ |
755a6d84 |
258 | } |
d4e1d591 |
259 | #endif |
755a6d84 |
260 | |
a0e16eb1 |
261 | static void sigchld_handler(int signum) |
262 | { |
74aca06d |
263 | write(pty_signal_pipe[1], "x", 1); |
a0e16eb1 |
264 | } |
265 | |
d4e1d591 |
266 | #ifndef OMIT_UTMP |
755a6d84 |
267 | static void fatal_sig_handler(int signum) |
268 | { |
0f33f9d1 |
269 | putty_signal(signum, SIG_DFL); |
755a6d84 |
270 | cleanup_utmp(); |
271 | setuid(getuid()); |
272 | raise(signum); |
273 | } |
d4e1d591 |
274 | #endif |
755a6d84 |
275 | |
d6fa1947 |
276 | static int pty_open_slave(Pty pty) |
270d2e8d |
277 | { |
89e97516 |
278 | if (pty->slave_fd < 0) { |
d6fa1947 |
279 | pty->slave_fd = open(pty->name, O_RDWR); |
db9b7dce |
280 | cloexec(pty->slave_fd); |
89e97516 |
281 | } |
270d2e8d |
282 | |
d6fa1947 |
283 | return pty->slave_fd; |
270d2e8d |
284 | } |
285 | |
d6fa1947 |
286 | static void pty_open_master(Pty pty) |
1709795f |
287 | { |
be4f86de |
288 | #ifdef BSD_PTYS |
95c47834 |
289 | const char chars1[] = "pqrstuvwxyz"; |
290 | const char chars2[] = "0123456789abcdef"; |
291 | const char *p1, *p2; |
292 | char master_name[20]; |
293 | struct group *gp; |
294 | |
295 | for (p1 = chars1; *p1; p1++) |
296 | for (p2 = chars2; *p2; p2++) { |
297 | sprintf(master_name, "/dev/pty%c%c", *p1, *p2); |
d6fa1947 |
298 | pty->master_fd = open(master_name, O_RDWR); |
299 | if (pty->master_fd >= 0) { |
95c47834 |
300 | if (geteuid() == 0 || |
270d2e8d |
301 | access(master_name, R_OK | W_OK) == 0) { |
302 | /* |
303 | * We must also check at this point that we are |
304 | * able to open the slave side of the pty. We |
305 | * wouldn't want to allocate the wrong master, |
306 | * get all the way down to forking, and _then_ |
307 | * find we're unable to open the slave. |
308 | */ |
d6fa1947 |
309 | strcpy(pty->name, master_name); |
310 | pty->name[5] = 't'; /* /dev/ptyXX -> /dev/ttyXX */ |
270d2e8d |
311 | |
db9b7dce |
312 | cloexec(pty->master_fd); |
89e97516 |
313 | |
d6fa1947 |
314 | if (pty_open_slave(pty) >= 0 && |
315 | access(pty->name, R_OK | W_OK) == 0) |
270d2e8d |
316 | goto got_one; |
d6fa1947 |
317 | if (pty->slave_fd > 0) |
318 | close(pty->slave_fd); |
319 | pty->slave_fd = -1; |
270d2e8d |
320 | } |
d6fa1947 |
321 | close(pty->master_fd); |
be4f86de |
322 | } |
95c47834 |
323 | } |
be4f86de |
324 | |
95c47834 |
325 | /* If we get here, we couldn't get a tty at all. */ |
326 | fprintf(stderr, "pterm: unable to open a pseudo-terminal device\n"); |
327 | exit(1); |
be4f86de |
328 | |
95c47834 |
329 | got_one: |
95c47834 |
330 | |
331 | /* We need to chown/chmod the /dev/ttyXX device. */ |
332 | gp = getgrnam("tty"); |
d6fa1947 |
333 | chown(pty->name, getuid(), gp ? gp->gr_gid : -1); |
334 | chmod(pty->name, 0600); |
be4f86de |
335 | #else |
d6fa1947 |
336 | pty->master_fd = open("/dev/ptmx", O_RDWR); |
054d8535 |
337 | |
d6fa1947 |
338 | if (pty->master_fd < 0) { |
054d8535 |
339 | perror("/dev/ptmx: open"); |
340 | exit(1); |
341 | } |
342 | |
d6fa1947 |
343 | if (grantpt(pty->master_fd) < 0) { |
054d8535 |
344 | perror("grantpt"); |
345 | exit(1); |
346 | } |
347 | |
d6fa1947 |
348 | if (unlockpt(pty->master_fd) < 0) { |
054d8535 |
349 | perror("unlockpt"); |
350 | exit(1); |
351 | } |
352 | |
db9b7dce |
353 | cloexec(pty->master_fd); |
89e97516 |
354 | |
d6fa1947 |
355 | pty->name[FILENAME_MAX-1] = '\0'; |
356 | strncpy(pty->name, ptsname(pty->master_fd), FILENAME_MAX-1); |
be4f86de |
357 | #endif |
d6fa1947 |
358 | |
2916fa14 |
359 | { |
360 | /* |
361 | * Set the pty master into non-blocking mode. |
362 | */ |
363 | int i = 1; |
364 | ioctl(pty->master_fd, FIONBIO, &i); |
365 | } |
366 | |
d6fa1947 |
367 | if (!ptys_by_fd) |
368 | ptys_by_fd = newtree234(pty_compare_by_fd); |
369 | add234(ptys_by_fd, pty); |
95c47834 |
370 | } |
054d8535 |
371 | |
95c47834 |
372 | /* |
373 | * Pre-initialisation. This is here to get around the fact that GTK |
374 | * doesn't like being run in setuid/setgid programs (probably |
375 | * sensibly). So before we initialise GTK - and therefore before we |
376 | * even process the command line - we check to see if we're running |
377 | * set[ug]id. If so, we open our pty master _now_, chown it as |
378 | * necessary, and drop privileges. We can always close it again |
379 | * later. If we're potentially going to be doing utmp as well, we |
380 | * also fork off a utmp helper process and communicate with it by |
381 | * means of a pipe; the utmp helper will keep privileges in order |
382 | * to clean up utmp when we exit (i.e. when its end of our pipe |
383 | * closes). |
384 | */ |
385 | void pty_pre_init(void) |
386 | { |
d6fa1947 |
387 | Pty pty; |
388 | |
d4e1d591 |
389 | #ifndef OMIT_UTMP |
95c47834 |
390 | pid_t pid; |
391 | int pipefd[2]; |
d4e1d591 |
392 | #endif |
95c47834 |
393 | |
d6fa1947 |
394 | pty = single_pty = snew(struct pty_tag); |
2916fa14 |
395 | bufchain_init(&pty->output_data); |
d6fa1947 |
396 | |
0f33f9d1 |
397 | /* set the child signal handler straight away; it needs to be set |
398 | * before we ever fork. */ |
399 | putty_signal(SIGCHLD, sigchld_handler); |
d6fa1947 |
400 | pty->master_fd = pty->slave_fd = -1; |
401 | #ifndef OMIT_UTMP |
402 | pty_stamped_utmp = FALSE; |
403 | #endif |
95c47834 |
404 | |
405 | if (geteuid() != getuid() || getegid() != getgid()) { |
d6fa1947 |
406 | pty_open_master(pty); |
39baeaa4 |
407 | } |
408 | |
95c47834 |
409 | #ifndef OMIT_UTMP |
39baeaa4 |
410 | /* |
95c47834 |
411 | * Fork off the utmp helper. |
755a6d84 |
412 | */ |
95c47834 |
413 | if (pipe(pipefd) < 0) { |
414 | perror("pterm: pipe"); |
415 | exit(1); |
416 | } |
417 | pid = fork(); |
418 | if (pid < 0) { |
419 | perror("pterm: fork"); |
420 | exit(1); |
421 | } else if (pid == 0) { |
422 | char display[128], buffer[128]; |
423 | int dlen, ret; |
424 | |
425 | close(pipefd[1]); |
426 | /* |
427 | * Now sit here until we receive a display name from the |
428 | * other end of the pipe, and then stamp utmp. Unstamp utmp |
429 | * again, and exit, when the pipe closes. |
430 | */ |
431 | |
432 | dlen = 0; |
433 | while (1) { |
434 | |
435 | ret = read(pipefd[0], buffer, lenof(buffer)); |
436 | if (ret <= 0) { |
437 | cleanup_utmp(); |
0f33f9d1 |
438 | _exit(0); |
95c47834 |
439 | } else if (!pty_stamped_utmp) { |
440 | if (dlen < lenof(display)) |
441 | memcpy(display+dlen, buffer, |
442 | min(ret, lenof(display)-dlen)); |
443 | if (buffer[ret-1] == '\0') { |
444 | /* |
445 | * Now we have a display name. NUL-terminate |
446 | * it, and stamp utmp. |
447 | */ |
448 | display[lenof(display)-1] = '\0'; |
449 | /* |
450 | * Trap as many fatal signals as we can in the |
451 | * hope of having the best possible chance to |
452 | * clean up utmp before termination. We are |
453 | * unfortunately unprotected against SIGKILL, |
454 | * but that's life. |
455 | */ |
0f33f9d1 |
456 | putty_signal(SIGHUP, fatal_sig_handler); |
457 | putty_signal(SIGINT, fatal_sig_handler); |
458 | putty_signal(SIGQUIT, fatal_sig_handler); |
459 | putty_signal(SIGILL, fatal_sig_handler); |
460 | putty_signal(SIGABRT, fatal_sig_handler); |
461 | putty_signal(SIGFPE, fatal_sig_handler); |
462 | putty_signal(SIGPIPE, fatal_sig_handler); |
463 | putty_signal(SIGALRM, fatal_sig_handler); |
464 | putty_signal(SIGTERM, fatal_sig_handler); |
465 | putty_signal(SIGSEGV, fatal_sig_handler); |
466 | putty_signal(SIGUSR1, fatal_sig_handler); |
467 | putty_signal(SIGUSR2, fatal_sig_handler); |
755a6d84 |
468 | #ifdef SIGBUS |
0f33f9d1 |
469 | putty_signal(SIGBUS, fatal_sig_handler); |
755a6d84 |
470 | #endif |
471 | #ifdef SIGPOLL |
0f33f9d1 |
472 | putty_signal(SIGPOLL, fatal_sig_handler); |
755a6d84 |
473 | #endif |
474 | #ifdef SIGPROF |
0f33f9d1 |
475 | putty_signal(SIGPROF, fatal_sig_handler); |
755a6d84 |
476 | #endif |
477 | #ifdef SIGSYS |
0f33f9d1 |
478 | putty_signal(SIGSYS, fatal_sig_handler); |
755a6d84 |
479 | #endif |
480 | #ifdef SIGTRAP |
0f33f9d1 |
481 | putty_signal(SIGTRAP, fatal_sig_handler); |
755a6d84 |
482 | #endif |
483 | #ifdef SIGVTALRM |
0f33f9d1 |
484 | putty_signal(SIGVTALRM, fatal_sig_handler); |
755a6d84 |
485 | #endif |
486 | #ifdef SIGXCPU |
0f33f9d1 |
487 | putty_signal(SIGXCPU, fatal_sig_handler); |
755a6d84 |
488 | #endif |
489 | #ifdef SIGXFSZ |
0f33f9d1 |
490 | putty_signal(SIGXFSZ, fatal_sig_handler); |
755a6d84 |
491 | #endif |
492 | #ifdef SIGIO |
0f33f9d1 |
493 | putty_signal(SIGIO, fatal_sig_handler); |
95c47834 |
494 | #endif |
d6fa1947 |
495 | setup_utmp(pty->name, display); |
95c47834 |
496 | } |
497 | } |
498 | } |
499 | } else { |
500 | close(pipefd[0]); |
501 | pty_utmp_helper_pid = pid; |
502 | pty_utmp_helper_pipe = pipefd[1]; |
503 | } |
755a6d84 |
504 | #endif |
95c47834 |
505 | |
506 | /* Drop privs. */ |
507 | { |
95c47834 |
508 | #ifndef HAVE_NO_SETRESUID |
d4e1d591 |
509 | int gid = getgid(), uid = getuid(); |
95c47834 |
510 | int setresgid(gid_t, gid_t, gid_t); |
511 | int setresuid(uid_t, uid_t, uid_t); |
512 | setresgid(gid, gid, gid); |
513 | setresuid(uid, uid, uid); |
514 | #else |
515 | setgid(getgid()); |
516 | setuid(getuid()); |
517 | #endif |
518 | } |
519 | } |
520 | |
d6fa1947 |
521 | int pty_real_select_result(Pty pty, int event, int status) |
74aca06d |
522 | { |
523 | char buf[4096]; |
524 | int ret; |
525 | int finished = FALSE; |
526 | |
d6fa1947 |
527 | if (event < 0) { |
74aca06d |
528 | /* |
d6fa1947 |
529 | * We've been called because our child process did |
530 | * something. `status' tells us what. |
74aca06d |
531 | */ |
d6fa1947 |
532 | if ((WIFEXITED(status) || WIFSIGNALED(status))) { |
74aca06d |
533 | /* |
d6fa1947 |
534 | * The primary child process died. We could keep |
535 | * the terminal open for remaining subprocesses to |
536 | * output to, but conventional wisdom seems to feel |
537 | * that that's the Wrong Thing for an xterm-alike, |
538 | * so we bail out now (though we don't necessarily |
539 | * _close_ the window, depending on the state of |
540 | * Close On Exit). This would be easy enough to |
541 | * change or make configurable if necessary. |
74aca06d |
542 | */ |
d6fa1947 |
543 | pty->exit_code = status; |
544 | pty->child_dead = TRUE; |
545 | del234(ptys_by_pid, pty); |
74aca06d |
546 | finished = TRUE; |
74aca06d |
547 | } |
d6fa1947 |
548 | } else { |
549 | if (event == 1) { |
74aca06d |
550 | |
d6fa1947 |
551 | ret = read(pty->master_fd, buf, sizeof(buf)); |
74aca06d |
552 | |
d6fa1947 |
553 | /* |
554 | * Clean termination condition is that either ret == 0, or ret |
555 | * < 0 and errno == EIO. Not sure why the latter, but it seems |
556 | * to happen. Boo. |
557 | */ |
558 | if (ret == 0 || (ret < 0 && errno == EIO)) { |
74aca06d |
559 | /* |
d6fa1947 |
560 | * We assume a clean exit if the pty has closed but the |
561 | * actual child process hasn't. The only way I can |
562 | * imagine this happening is if it detaches itself from |
563 | * the pty and goes daemonic - in which case the |
564 | * expected usage model would precisely _not_ be for |
565 | * the pterm window to hang around! |
74aca06d |
566 | */ |
74aca06d |
567 | finished = TRUE; |
d6fa1947 |
568 | if (!pty->child_dead) |
569 | pty->exit_code = 0; |
570 | } else if (ret < 0) { |
571 | perror("read pty master"); |
572 | exit(1); |
573 | } else if (ret > 0) { |
574 | from_backend(pty->frontend, 0, buf, ret); |
74aca06d |
575 | } |
2916fa14 |
576 | } else if (event == 2) { |
577 | /* |
578 | * Attempt to send data down the pty. |
579 | */ |
580 | pty_try_write(pty); |
581 | } |
74aca06d |
582 | } |
583 | |
d6fa1947 |
584 | if (finished && !pty->finished) { |
585 | uxsel_del(pty->master_fd); |
586 | pty_close(pty); |
587 | pty->master_fd = -1; |
74aca06d |
588 | |
d6fa1947 |
589 | pty->finished = TRUE; |
74aca06d |
590 | |
591 | /* |
592 | * This is a slight layering-violation sort of hack: only |
593 | * if we're not closing on exit (COE is set to Never, or to |
594 | * Only On Clean and it wasn't a clean exit) do we output a |
595 | * `terminated' message. |
596 | */ |
d6fa1947 |
597 | if (pty->cfg.close_on_exit == FORCE_OFF || |
598 | (pty->cfg.close_on_exit == AUTO && pty->exit_code != 0)) { |
74aca06d |
599 | char message[512]; |
d6fa1947 |
600 | if (WIFEXITED(pty->exit_code)) |
74aca06d |
601 | sprintf(message, "\r\n[pterm: process terminated with exit" |
d6fa1947 |
602 | " code %d]\r\n", WEXITSTATUS(pty->exit_code)); |
603 | else if (WIFSIGNALED(pty->exit_code)) |
74aca06d |
604 | #ifdef HAVE_NO_STRSIGNAL |
605 | sprintf(message, "\r\n[pterm: process terminated on signal" |
d6fa1947 |
606 | " %d]\r\n", WTERMSIG(pty->exit_code)); |
74aca06d |
607 | #else |
608 | sprintf(message, "\r\n[pterm: process terminated on signal" |
d6fa1947 |
609 | " %d (%.400s)]\r\n", WTERMSIG(pty->exit_code), |
610 | strsignal(WTERMSIG(pty->exit_code))); |
74aca06d |
611 | #endif |
d6fa1947 |
612 | from_backend(pty->frontend, 0, message, strlen(message)); |
74aca06d |
613 | } |
39934deb |
614 | |
d6fa1947 |
615 | notify_remote_exit(pty->frontend); |
74aca06d |
616 | } |
d6fa1947 |
617 | |
74aca06d |
618 | return !finished; |
619 | } |
620 | |
d6fa1947 |
621 | int pty_select_result(int fd, int event) |
74aca06d |
622 | { |
d6fa1947 |
623 | int ret = TRUE; |
624 | Pty pty; |
625 | |
626 | if (fd == pty_signal_pipe[0]) { |
627 | pid_t pid; |
628 | int ipid; |
629 | int status; |
630 | char c[1]; |
631 | |
632 | read(pty_signal_pipe[0], c, 1); /* ignore its value; it'll be `x' */ |
633 | |
634 | do { |
635 | pid = waitpid(-1, &status, WNOHANG); |
636 | |
637 | ipid = pid; |
638 | pty = find234(ptys_by_pid, &pid, pty_find_by_pid); |
639 | |
640 | if (pty) |
641 | ret = ret && pty_real_select_result(pty, -1, status); |
642 | } while (pid > 0); |
643 | } else { |
644 | pty = find234(ptys_by_fd, &fd, pty_find_by_fd); |
645 | |
646 | if (pty) |
647 | ret = ret && pty_real_select_result(pty, event, 0); |
648 | } |
649 | |
650 | return ret; |
651 | } |
652 | |
653 | static void pty_uxsel_setup(Pty pty) |
654 | { |
2916fa14 |
655 | int rwx; |
656 | |
657 | rwx = 1; /* always want to read from pty */ |
658 | if (bufchain_size(&pty->output_data)) |
659 | rwx |= 2; /* might also want to write to it */ |
660 | uxsel_set(pty->master_fd, rwx, pty_select_result); |
d6fa1947 |
661 | |
662 | /* |
663 | * In principle this only needs calling once for all pty |
664 | * backend instances, but it's simplest just to call it every |
665 | * time; uxsel won't mind. |
666 | */ |
74aca06d |
667 | uxsel_set(pty_signal_pipe[0], 1, pty_select_result); |
668 | } |
669 | |
95c47834 |
670 | /* |
671 | * Called to set up the pty. |
672 | * |
673 | * Returns an error message, or NULL on success. |
674 | * |
675 | * Also places the canonical host name into `realhost'. It must be |
676 | * freed by the caller. |
677 | */ |
cbe2d68f |
678 | static const char *pty_init(void *frontend, void **backend_handle, Config *cfg, |
79bf227b |
679 | char *host, int port, char **realhost, int nodelay, |
680 | int keepalive) |
95c47834 |
681 | { |
682 | int slavefd; |
683 | pid_t pid, pgrp; |
c13772b1 |
684 | #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */ |
7af753e6 |
685 | long windowid; |
c13772b1 |
686 | #endif |
d6fa1947 |
687 | Pty pty; |
95c47834 |
688 | |
d6fa1947 |
689 | if (single_pty) { |
690 | pty = single_pty; |
691 | } else { |
692 | pty = snew(struct pty_tag); |
693 | pty->master_fd = pty->slave_fd = -1; |
694 | #ifndef OMIT_UTMP |
695 | pty_stamped_utmp = FALSE; |
696 | #endif |
697 | } |
698 | |
699 | pty->frontend = frontend; |
28d00fe4 |
700 | *backend_handle = NULL; /* we can't sensibly use this, sadly */ |
701 | |
d6fa1947 |
702 | pty->cfg = *cfg; /* structure copy */ |
703 | pty->term_width = cfg->width; |
704 | pty->term_height = cfg->height; |
f278d6f8 |
705 | |
d6fa1947 |
706 | if (pty->master_fd < 0) |
707 | pty_open_master(pty); |
95c47834 |
708 | |
709 | /* |
710 | * Set the backspace character to be whichever of ^H and ^? is |
711 | * specified by bksp_is_delete. |
712 | */ |
713 | { |
714 | struct termios attrs; |
d6fa1947 |
715 | tcgetattr(pty->master_fd, &attrs); |
86916870 |
716 | attrs.c_cc[VERASE] = cfg->bksp_is_delete ? '\177' : '\010'; |
d6fa1947 |
717 | tcsetattr(pty->master_fd, TCSANOW, &attrs); |
95c47834 |
718 | } |
719 | |
d4e1d591 |
720 | #ifndef OMIT_UTMP |
95c47834 |
721 | /* |
722 | * Stamp utmp (that is, tell the utmp helper process to do so), |
723 | * or not. |
724 | */ |
58dcb876 |
725 | if (!cfg->stamp_utmp) { |
95c47834 |
726 | close(pty_utmp_helper_pipe); /* just let the child process die */ |
58dcb876 |
727 | pty_utmp_helper_pipe = -1; |
728 | } else { |
d6fa1947 |
729 | char *location = get_x_display(pty->frontend); |
95c47834 |
730 | int len = strlen(location)+1, pos = 0; /* +1 to include NUL */ |
731 | while (pos < len) { |
732 | int ret = write(pty_utmp_helper_pipe, location+pos, len - pos); |
733 | if (ret < 0) { |
734 | perror("pterm: writing to utmp helper process"); |
735 | close(pty_utmp_helper_pipe); /* arrgh, just give up */ |
58dcb876 |
736 | pty_utmp_helper_pipe = -1; |
95c47834 |
737 | break; |
738 | } |
739 | pos += ret; |
740 | } |
741 | } |
d4e1d591 |
742 | #endif |
755a6d84 |
743 | |
c13772b1 |
744 | #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */ |
d6fa1947 |
745 | windowid = get_windowid(pty->frontend); |
c13772b1 |
746 | #endif |
7af753e6 |
747 | |
755a6d84 |
748 | /* |
054d8535 |
749 | * Fork and execute the command. |
750 | */ |
751 | pid = fork(); |
752 | if (pid < 0) { |
753 | perror("fork"); |
88e6b9ca |
754 | exit(1); |
054d8535 |
755 | } |
756 | |
757 | if (pid == 0) { |
758 | int i; |
759 | /* |
760 | * We are the child. |
761 | */ |
d37c2d81 |
762 | |
d6fa1947 |
763 | slavefd = pty_open_slave(pty); |
d37c2d81 |
764 | if (slavefd < 0) { |
765 | perror("slave pty: open"); |
0f33f9d1 |
766 | _exit(1); |
d37c2d81 |
767 | } |
768 | |
d6fa1947 |
769 | close(pty->master_fd); |
054d8535 |
770 | fcntl(slavefd, F_SETFD, 0); /* don't close on exec */ |
771 | dup2(slavefd, 0); |
772 | dup2(slavefd, 1); |
773 | dup2(slavefd, 2); |
774 | setsid(); |
bbaa7993 |
775 | #ifdef TIOCSCTTY |
d37c2d81 |
776 | ioctl(slavefd, TIOCSCTTY, 1); |
bbaa7993 |
777 | #endif |
d37c2d81 |
778 | pgrp = getpid(); |
779 | tcsetpgrp(slavefd, pgrp); |
ea0716c6 |
780 | setpgid(pgrp, pgrp); |
d6fa1947 |
781 | close(open(pty->name, O_WRONLY, 0)); |
ea0716c6 |
782 | setpgid(pgrp, pgrp); |
054d8535 |
783 | /* Close everything _else_, for tidiness. */ |
784 | for (i = 3; i < 1024; i++) |
785 | close(i); |
fe9548aa |
786 | { |
30d1257c |
787 | char *term_env_var = dupprintf("TERM=%s", cfg->termtype); |
fe9548aa |
788 | putenv(term_env_var); |
30d1257c |
789 | /* We mustn't free term_env_var, as putenv links it into the |
790 | * environment in place. |
791 | */ |
fe9548aa |
792 | } |
c13772b1 |
793 | #ifndef NOT_X_WINDOWS /* for Mac OS X native compilation */ |
7af753e6 |
794 | { |
30d1257c |
795 | char *windowid_env_var = dupprintf("WINDOWID=%ld", windowid); |
7af753e6 |
796 | putenv(windowid_env_var); |
30d1257c |
797 | /* We mustn't free windowid_env_var, as putenv links it into the |
798 | * environment in place. |
799 | */ |
7af753e6 |
800 | } |
c13772b1 |
801 | #endif |
73feed4f |
802 | { |
803 | char *e = cfg->environmt; |
804 | char *var, *varend, *val, *varval; |
805 | while (*e) { |
806 | var = e; |
807 | while (*e && *e != '\t') e++; |
808 | varend = e; |
809 | if (*e == '\t') e++; |
810 | val = e; |
811 | while (*e) e++; |
812 | e++; |
813 | |
814 | varval = dupprintf("%.*s=%s", varend-var, var, val); |
815 | putenv(varval); |
816 | /* |
817 | * We must not free varval, since putenv links it |
818 | * into the environment _in place_. Weird, but |
819 | * there we go. Memory usage will be rationalised |
820 | * as soon as we exec anyway. |
821 | */ |
822 | } |
823 | } |
824 | |
8bf5c419 |
825 | /* |
826 | * SIGINT and SIGQUIT may have been set to ignored by our |
827 | * parent, particularly by things like sh -c 'pterm &' and |
15b5d988 |
828 | * some window managers. SIGCHLD, meanwhile, was blocked |
829 | * during pt_main() startup. Reverse all this for our child |
830 | * process. |
8bf5c419 |
831 | */ |
0f33f9d1 |
832 | putty_signal(SIGINT, SIG_DFL); |
833 | putty_signal(SIGQUIT, SIG_DFL); |
15b5d988 |
834 | block_signal(SIGCHLD, 0); |
6169c758 |
835 | if (pty_argv) |
836 | execvp(pty_argv[0], pty_argv); |
c8ee61b9 |
837 | else { |
838 | char *shell = getenv("SHELL"); |
839 | char *shellname; |
86916870 |
840 | if (cfg->login_shell) { |
c8ee61b9 |
841 | char *p = strrchr(shell, '/'); |
3d88e64d |
842 | shellname = snewn(2+strlen(shell), char); |
c8ee61b9 |
843 | p = p ? p+1 : shell; |
844 | sprintf(shellname, "-%s", p); |
845 | } else |
846 | shellname = shell; |
30264db9 |
847 | execl(getenv("SHELL"), shellname, (void *)NULL); |
c8ee61b9 |
848 | } |
849 | |
054d8535 |
850 | /* |
851 | * If we're here, exec has gone badly foom. |
852 | */ |
853 | perror("exec"); |
0f33f9d1 |
854 | _exit(127); |
054d8535 |
855 | } else { |
d6fa1947 |
856 | pty->child_pid = pid; |
857 | pty->child_dead = FALSE; |
858 | pty->finished = FALSE; |
859 | if (pty->slave_fd > 0) |
860 | close(pty->slave_fd); |
861 | if (!ptys_by_pid) |
862 | ptys_by_pid = newtree234(pty_compare_by_pid); |
863 | add234(ptys_by_pid, pty); |
270d2e8d |
864 | } |
054d8535 |
865 | |
d6fa1947 |
866 | if (pty_signal_pipe[0] < 0 && pipe(pty_signal_pipe) < 0) { |
74aca06d |
867 | perror("pipe"); |
868 | exit(1); |
869 | } |
d6fa1947 |
870 | pty_uxsel_setup(pty); |
871 | |
872 | *backend_handle = pty; |
74aca06d |
873 | |
5617c1e6 |
874 | *realhost = dupprintf("\0"); |
875 | |
1709795f |
876 | return NULL; |
877 | } |
878 | |
86916870 |
879 | static void pty_reconfig(void *handle, Config *cfg) |
880 | { |
d6fa1947 |
881 | Pty pty = (Pty)handle; |
6b0eeb4e |
882 | /* |
883 | * We don't have much need to reconfigure this backend, but |
884 | * unfortunately we do need to pick up the setting of Close On |
885 | * Exit so we know whether to give a `terminated' message. |
886 | */ |
d6fa1947 |
887 | pty->cfg = *cfg; /* structure copy */ |
86916870 |
888 | } |
889 | |
890 | /* |
6b0eeb4e |
891 | * Stub routine (never called in pterm). |
cb60dcb3 |
892 | */ |
893 | static void pty_free(void *handle) |
894 | { |
d6fa1947 |
895 | Pty pty = (Pty)handle; |
896 | |
897 | /* Either of these may fail `not found'. That's fine with us. */ |
898 | del234(ptys_by_pid, pty); |
899 | del234(ptys_by_fd, pty); |
900 | |
901 | sfree(pty); |
cb60dcb3 |
902 | } |
903 | |
2916fa14 |
904 | static void pty_try_write(Pty pty) |
905 | { |
906 | void *data; |
907 | int len, ret; |
908 | |
909 | assert(pty->master_fd >= 0); |
910 | |
911 | while (bufchain_size(&pty->output_data) > 0) { |
912 | bufchain_prefix(&pty->output_data, &data, &len); |
913 | ret = write(pty->master_fd, data, len); |
914 | |
915 | if (ret < 0 && (errno == EWOULDBLOCK)) { |
916 | /* |
917 | * We've sent all we can for the moment. |
918 | */ |
919 | break; |
920 | } |
921 | if (ret < 0) { |
922 | perror("write pty master"); |
923 | exit(1); |
924 | } |
925 | bufchain_consume(&pty->output_data, ret); |
926 | } |
927 | |
928 | pty_uxsel_setup(pty); |
929 | } |
930 | |
cb60dcb3 |
931 | /* |
1709795f |
932 | * Called to send data down the pty. |
933 | */ |
28d00fe4 |
934 | static int pty_send(void *handle, char *buf, int len) |
1709795f |
935 | { |
d6fa1947 |
936 | Pty pty = (Pty)handle; |
937 | |
938 | if (pty->master_fd < 0) |
2916fa14 |
939 | return 0; /* ignore all writes if fd closed */ |
90cfd8f4 |
940 | |
2916fa14 |
941 | bufchain_add(&pty->output_data, buf, len); |
942 | pty_try_write(pty); |
943 | |
944 | return bufchain_size(&pty->output_data); |
1709795f |
945 | } |
946 | |
d6fa1947 |
947 | static void pty_close(Pty pty) |
90cfd8f4 |
948 | { |
d6fa1947 |
949 | if (pty->master_fd >= 0) { |
950 | close(pty->master_fd); |
951 | pty->master_fd = -1; |
90cfd8f4 |
952 | } |
d4e1d591 |
953 | #ifndef OMIT_UTMP |
58dcb876 |
954 | if (pty_utmp_helper_pipe >= 0) { |
955 | close(pty_utmp_helper_pipe); /* this causes utmp to be cleaned up */ |
956 | pty_utmp_helper_pipe = -1; |
957 | } |
d4e1d591 |
958 | #endif |
90cfd8f4 |
959 | } |
960 | |
1709795f |
961 | /* |
962 | * Called to query the current socket sendability status. |
963 | */ |
28d00fe4 |
964 | static int pty_sendbuffer(void *handle) |
1709795f |
965 | { |
d6fa1947 |
966 | /* Pty pty = (Pty)handle; */ |
1709795f |
967 | return 0; |
968 | } |
969 | |
970 | /* |
971 | * Called to set the size of the window |
972 | */ |
28d00fe4 |
973 | static void pty_size(void *handle, int width, int height) |
1709795f |
974 | { |
d6fa1947 |
975 | Pty pty = (Pty)handle; |
88e6b9ca |
976 | struct winsize size; |
977 | |
d6fa1947 |
978 | pty->term_width = width; |
979 | pty->term_height = height; |
f278d6f8 |
980 | |
d6fa1947 |
981 | size.ws_row = (unsigned short)pty->term_height; |
982 | size.ws_col = (unsigned short)pty->term_width; |
983 | size.ws_xpixel = (unsigned short) pty->term_width * |
984 | font_dimension(pty->frontend, 0); |
985 | size.ws_ypixel = (unsigned short) pty->term_height * |
986 | font_dimension(pty->frontend, 1); |
987 | ioctl(pty->master_fd, TIOCSWINSZ, (void *)&size); |
1709795f |
988 | return; |
989 | } |
990 | |
991 | /* |
992 | * Send special codes. |
993 | */ |
28d00fe4 |
994 | static void pty_special(void *handle, Telnet_Special code) |
1709795f |
995 | { |
d6fa1947 |
996 | /* Pty pty = (Pty)handle; */ |
1709795f |
997 | /* Do nothing! */ |
998 | return; |
999 | } |
1000 | |
125105d1 |
1001 | /* |
1002 | * Return a list of the special codes that make sense in this |
1003 | * protocol. |
1004 | */ |
1005 | static const struct telnet_special *pty_get_specials(void *handle) |
1006 | { |
d6fa1947 |
1007 | /* Pty pty = (Pty)handle; */ |
125105d1 |
1008 | /* |
1009 | * Hmm. When I get round to having this actually usable, it |
1010 | * might be quite nice to have the ability to deliver a few |
1011 | * well chosen signals to the child process - SIGINT, SIGTERM, |
1012 | * SIGKILL at least. |
1013 | */ |
1014 | return NULL; |
1015 | } |
1016 | |
6226c939 |
1017 | static int pty_connected(void *handle) |
1709795f |
1018 | { |
d6fa1947 |
1019 | /* Pty pty = (Pty)handle; */ |
6226c939 |
1020 | return TRUE; |
1709795f |
1021 | } |
1022 | |
28d00fe4 |
1023 | static int pty_sendok(void *handle) |
1709795f |
1024 | { |
d6fa1947 |
1025 | /* Pty pty = (Pty)handle; */ |
1709795f |
1026 | return 1; |
1027 | } |
1028 | |
28d00fe4 |
1029 | static void pty_unthrottle(void *handle, int backlog) |
1709795f |
1030 | { |
d6fa1947 |
1031 | /* Pty pty = (Pty)handle; */ |
1709795f |
1032 | /* do nothing */ |
1033 | } |
1034 | |
28d00fe4 |
1035 | static int pty_ldisc(void *handle, int option) |
1709795f |
1036 | { |
d6fa1947 |
1037 | /* Pty pty = (Pty)handle; */ |
1709795f |
1038 | return 0; /* neither editing nor echoing */ |
1039 | } |
1040 | |
b9d7bcad |
1041 | static void pty_provide_ldisc(void *handle, void *ldisc) |
1042 | { |
d6fa1947 |
1043 | /* Pty pty = (Pty)handle; */ |
b9d7bcad |
1044 | /* This is a stub. */ |
1045 | } |
1046 | |
a8327734 |
1047 | static void pty_provide_logctx(void *handle, void *logctx) |
1048 | { |
d6fa1947 |
1049 | /* Pty pty = (Pty)handle; */ |
a8327734 |
1050 | /* This is a stub. */ |
1051 | } |
1052 | |
28d00fe4 |
1053 | static int pty_exitcode(void *handle) |
1709795f |
1054 | { |
d6fa1947 |
1055 | Pty pty = (Pty)handle; |
1056 | if (!pty->finished) |
90cfd8f4 |
1057 | return -1; /* not dead yet */ |
1058 | else |
d6fa1947 |
1059 | return pty->exit_code; |
1709795f |
1060 | } |
1061 | |
f89c3294 |
1062 | static int pty_cfg_info(void *handle) |
1063 | { |
d6fa1947 |
1064 | /* Pty pty = (Pty)handle; */ |
f89c3294 |
1065 | return 0; |
1066 | } |
1067 | |
1709795f |
1068 | Backend pty_backend = { |
1069 | pty_init, |
cb60dcb3 |
1070 | pty_free, |
86916870 |
1071 | pty_reconfig, |
1709795f |
1072 | pty_send, |
1073 | pty_sendbuffer, |
1074 | pty_size, |
1075 | pty_special, |
125105d1 |
1076 | pty_get_specials, |
6226c939 |
1077 | pty_connected, |
1709795f |
1078 | pty_exitcode, |
1079 | pty_sendok, |
1080 | pty_ldisc, |
b9d7bcad |
1081 | pty_provide_ldisc, |
a8327734 |
1082 | pty_provide_logctx, |
1709795f |
1083 | pty_unthrottle, |
f89c3294 |
1084 | pty_cfg_info, |
1709795f |
1085 | 1 |
1086 | }; |