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- Committer: Teddy Hogeborn
- Date: 2008-08-16 03:29:08 UTC
- Revision ID: teddy@fukt.bsnet.se-20080816032908-ihw7c05r2mnyk389
Add feature to specify custom environment variables for plugins.
* plugin-runner.c (plugin): New members "environ" and "envc" to
contain possible custom environment.
(getplugin): Return NULL on failure instead of doing exit(); all
callers changed.
(add_to_char_array): New helper function for "add_argument" and
"add_environment".
(addargument): Renamed to "add_argument". Return bool. Call
"add_to_char_array" to actually do things.
(add_environment): New; analogous to "add_argument".
(addcustomargument): Renamed to "add_to_argv" to avoid confusion
with "add_argument".
(main): New options "--global-envs" and "--envs-for" to specify
custom environment for plugins. Print environment for
plugins in debug mode. Use asprintf instead of strcpy and
strcat. Use execve() for plugins with custom environments.
Free environment for plugin when freeing plugin list.
* plugin-runner.c (plugin): New members "environ" and "envc" to
contain possible custom environment.
(getplugin): Return NULL on failure instead of doing exit(); all
callers changed.
(add_to_char_array): New helper function for "add_argument" and
"add_environment".
(addargument): Renamed to "add_argument". Return bool. Call
"add_to_char_array" to actually do things.
(add_environment): New; analogous to "add_argument".
(addcustomargument): Renamed to "add_to_argv" to avoid confusion
with "add_argument".
(main): New options "--global-envs" and "--envs-for" to specify
custom environment for plugins. Print environment for
plugins in debug mode. Use asprintf instead of strcpy and
strcat. Use execve() for plugins with custom environments.
Free environment for plugin when freeing plugin list.
- files added:
- network-protocol.txt
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/upstream
- network-hooks.d
- plugin-helpers
- files renamed:
- plugins.d/mandos-client.c => plugins.d/password-request.c
- plugins.d/mandos-client.xml => plugins.d/password-request.xml
- files modified:
- Makefile
added
removed
plugins.d/usplash.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Usplash - Read a password from usplash and output it
4
*
5
* Copyright © 2008-2017 Teddy Hogeborn
6
* Copyright © 2008-2017 Björn Påhlsson
7
*
8
* This file is part of Mandos.
9
*
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
14
*
15
* Mandos is distributed in the hope that it will be useful, but
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
* General Public License for more details.
19
*
20
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
22
*
23
* Contact the authors at <mandos@recompile.se>.
24
*/
25
26
#define _GNU_SOURCE /* asprintf(), TEMP_FAILURE_RETRY() */
27
#include <signal.h> /* sig_atomic_t, struct sigaction,
28
sigemptyset(), sigaddset(), SIGINT,
29
SIGHUP, SIGTERM, sigaction(),
30
SIG_IGN, kill(), SIGKILL */
31
#include <stdbool.h> /* bool, false, true */
32
#include <fcntl.h> /* open(), O_WRONLY, O_RDONLY */
33
#include <iso646.h> /* and, or, not*/
34
#include <errno.h> /* errno, EINTR */
35
#include <error.h>
36
#include <sys/types.h> /* size_t, ssize_t, pid_t, DIR, struct
37
dirent */
38
#include <stddef.h> /* NULL */
39
#include <string.h> /* strlen(), memcmp(), strerror() */
40
#include <stdio.h> /* asprintf(), vasprintf(), vprintf(),
41
fprintf() */
42
#include <unistd.h> /* close(), write(), readlink(),
43
read(), STDOUT_FILENO, sleep(),
44
fork(), setuid(), geteuid(),
45
setsid(), chdir(), dup2(),
46
STDERR_FILENO, execv() */
47
#include <stdlib.h> /* free(), EXIT_FAILURE, realloc(),
48
EXIT_SUCCESS, malloc(), _exit(),
49
getenv() */
50
#include <dirent.h> /* opendir(), readdir(), closedir() */
51
#include <inttypes.h> /* intmax_t, strtoimax() */
52
#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
53
#include <sysexits.h> /* EX_OSERR, EX_UNAVAILABLE */
54
#include <argz.h> /* argz_count(), argz_extract() */
55
#include <stdarg.h> /* va_list, va_start(), ... */
56
57
sig_atomic_t interrupted_by_signal = 0;
58
int signal_received;
59
const char usplash_name[] = "/sbin/usplash";
60
61
/* Function to use when printing errors */
62
__attribute__((format (gnu_printf, 3, 4)))
63
void error_plus(int status, int errnum, const char *formatstring,
64
...){
65
va_list ap;
66
char *text;
67
int ret;
68
69
va_start(ap, formatstring);
70
ret = vasprintf(&text, formatstring, ap);
71
if(ret == -1){
72
fprintf(stderr, "Mandos plugin %s: ",
73
program_invocation_short_name);
74
vfprintf(stderr, formatstring, ap);
75
fprintf(stderr, ": ");
76
fprintf(stderr, "%s\n", strerror(errnum));
77
error(status, errno, "vasprintf while printing error");
78
return;
79
}
80
fprintf(stderr, "Mandos plugin ");
81
error(status, errnum, "%s", text);
82
free(text);
83
}
84
85
static void termination_handler(int signum){
86
if(interrupted_by_signal){
87
return;
88
}
89
interrupted_by_signal = 1;
90
signal_received = signum;
91
}
92
93
static bool usplash_write(int *fifo_fd_r,
94
const char *cmd, const char *arg){
95
/*
96
* usplash_write(&fd, "TIMEOUT", "15") will write "TIMEOUT 15\0"
97
* usplash_write(&fd, "PULSATE", NULL) will write "PULSATE\0"
98
* SEE ALSO
99
* usplash_write(8)
100
*/
101
int ret;
102
if(*fifo_fd_r == -1){
103
ret = open("/dev/.initramfs/usplash_fifo", O_WRONLY);
104
if(ret == -1){
105
return false;
106
}
107
*fifo_fd_r = ret;
108
}
109
110
const char *cmd_line;
111
size_t cmd_line_len;
112
char *cmd_line_alloc = NULL;
113
if(arg == NULL){
114
cmd_line = cmd;
115
cmd_line_len = strlen(cmd) + 1;
116
} else {
117
do {
118
ret = asprintf(&cmd_line_alloc, "%s %s", cmd, arg);
119
if(ret == -1){
120
int e = errno;
121
close(*fifo_fd_r);
122
errno = e;
123
return false;
124
}
125
} while(ret == -1);
126
cmd_line = cmd_line_alloc;
127
cmd_line_len = (size_t)ret + 1;
128
}
129
130
size_t written = 0;
131
ssize_t sret = 0;
132
while(written < cmd_line_len){
133
sret = write(*fifo_fd_r, cmd_line + written,
134
cmd_line_len - written);
135
if(sret == -1){
136
int e = errno;
137
close(*fifo_fd_r);
138
free(cmd_line_alloc);
139
errno = e;
140
return false;
141
}
142
written += (size_t)sret;
143
}
144
free(cmd_line_alloc);
145
146
return true;
147
}
148
149
/* Create prompt string */
150
char *makeprompt(void){
151
int ret = 0;
152
char *prompt;
153
const char *const cryptsource = getenv("cryptsource");
154
const char *const crypttarget = getenv("crypttarget");
155
const char prompt_start[] = "Enter passphrase to unlock the disk";
156
157
if(cryptsource == NULL){
158
if(crypttarget == NULL){
159
ret = asprintf(&prompt, "%s: ", prompt_start);
160
} else {
161
ret = asprintf(&prompt, "%s (%s): ", prompt_start,
162
crypttarget);
163
}
164
} else {
165
if(crypttarget == NULL){
166
ret = asprintf(&prompt, "%s %s: ", prompt_start, cryptsource);
167
} else {
168
ret = asprintf(&prompt, "%s %s (%s): ", prompt_start,
169
cryptsource, crypttarget);
170
}
171
}
172
if(ret == -1){
173
return NULL;
174
}
175
return prompt;
176
}
177
178
pid_t find_usplash(char **cmdline_r, size_t *cmdline_len_r){
179
int ret = 0;
180
ssize_t sret = 0;
181
char *cmdline = NULL;
182
size_t cmdline_len = 0;
183
DIR *proc_dir = opendir("/proc");
184
if(proc_dir == NULL){
185
error_plus(0, errno, "opendir");
186
return -1;
187
}
188
errno = 0;
189
for(struct dirent *proc_ent = readdir(proc_dir);
190
proc_ent != NULL;
191
proc_ent = readdir(proc_dir)){
192
pid_t pid;
193
{
194
intmax_t tmpmax;
195
char *tmp;
196
tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
197
if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
198
or tmpmax != (pid_t)tmpmax){
199
/* Not a process */
200
errno = 0;
201
continue;
202
}
203
pid = (pid_t)tmpmax;
204
}
205
/* Find the executable name by doing readlink() on the
206
/proc/<pid>/exe link */
207
char exe_target[sizeof(usplash_name)];
208
{
209
/* create file name string */
210
char *exe_link;
211
ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
212
if(ret == -1){
213
error_plus(0, errno, "asprintf");
214
goto fail_find_usplash;
215
}
216
217
/* Check that it refers to a symlink owned by root:root */
218
struct stat exe_stat;
219
ret = lstat(exe_link, &exe_stat);
220
if(ret == -1){
221
if(errno == ENOENT){
222
free(exe_link);
223
continue;
224
}
225
error_plus(0, errno, "lstat");
226
free(exe_link);
227
goto fail_find_usplash;
228
}
229
if(not S_ISLNK(exe_stat.st_mode)
230
or exe_stat.st_uid != 0
231
or exe_stat.st_gid != 0){
232
free(exe_link);
233
continue;
234
}
235
236
sret = readlink(exe_link, exe_target, sizeof(exe_target));
237
free(exe_link);
238
}
239
/* Compare executable name */
240
if((sret != ((ssize_t)sizeof(exe_target)-1))
241
or (memcmp(usplash_name, exe_target,
242
sizeof(exe_target)-1) != 0)){
243
/* Not it */
244
continue;
245
}
246
/* Found usplash */
247
/* Read and save the command line of usplash in "cmdline" */
248
{
249
/* Open /proc/<pid>/cmdline */
250
int cl_fd;
251
{
252
char *cmdline_filename;
253
ret = asprintf(&cmdline_filename, "/proc/%s/cmdline",
254
proc_ent->d_name);
255
if(ret == -1){
256
error_plus(0, errno, "asprintf");
257
goto fail_find_usplash;
258
}
259
cl_fd = open(cmdline_filename, O_RDONLY);
260
free(cmdline_filename);
261
if(cl_fd == -1){
262
error_plus(0, errno, "open");
263
goto fail_find_usplash;
264
}
265
}
266
size_t cmdline_allocated = 0;
267
char *tmp;
268
const size_t blocksize = 1024;
269
do {
270
/* Allocate more space? */
271
if(cmdline_len + blocksize > cmdline_allocated){
272
tmp = realloc(cmdline, cmdline_allocated + blocksize);
273
if(tmp == NULL){
274
error_plus(0, errno, "realloc");
275
close(cl_fd);
276
goto fail_find_usplash;
277
}
278
cmdline = tmp;
279
cmdline_allocated += blocksize;
280
}
281
/* Read data */
282
sret = read(cl_fd, cmdline + cmdline_len,
283
cmdline_allocated - cmdline_len);
284
if(sret == -1){
285
error_plus(0, errno, "read");
286
close(cl_fd);
287
goto fail_find_usplash;
288
}
289
cmdline_len += (size_t)sret;
290
} while(sret != 0);
291
ret = close(cl_fd);
292
if(ret == -1){
293
error_plus(0, errno, "close");
294
goto fail_find_usplash;
295
}
296
}
297
/* Close directory */
298
ret = closedir(proc_dir);
299
if(ret == -1){
300
error_plus(0, errno, "closedir");
301
goto fail_find_usplash;
302
}
303
/* Success */
304
*cmdline_r = cmdline;
305
*cmdline_len_r = cmdline_len;
306
return pid;
307
}
308
309
fail_find_usplash:
310
311
free(cmdline);
312
if(proc_dir != NULL){
313
int e = errno;
314
closedir(proc_dir);
315
errno = e;
316
}
317
return 0;
318
}
319
320
int main(__attribute__((unused))int argc,
321
__attribute__((unused))char **argv){
322
int ret = 0;
323
ssize_t sret;
324
int fifo_fd = -1;
325
int outfifo_fd = -1;
326
char *buf = NULL;
327
size_t buf_len = 0;
328
pid_t usplash_pid = -1;
329
bool usplash_accessed = false;
330
int status = EXIT_FAILURE; /* Default failure exit status */
331
332
char *prompt = makeprompt();
333
if(prompt == NULL){
334
status = EX_OSERR;
335
goto failure;
336
}
337
338
/* Find usplash process */
339
char *cmdline = NULL;
340
size_t cmdline_len = 0;
341
usplash_pid = find_usplash(&cmdline, &cmdline_len);
342
if(usplash_pid == 0){
343
status = EX_UNAVAILABLE;
344
goto failure;
345
}
346
347
/* Set up the signal handler */
348
{
349
struct sigaction old_action,
350
new_action = { .sa_handler = termination_handler,
351
.sa_flags = 0 };
352
sigemptyset(&new_action.sa_mask);
353
ret = sigaddset(&new_action.sa_mask, SIGINT);
354
if(ret == -1){
355
error_plus(0, errno, "sigaddset");
356
status = EX_OSERR;
357
goto failure;
358
}
359
ret = sigaddset(&new_action.sa_mask, SIGHUP);
360
if(ret == -1){
361
error_plus(0, errno, "sigaddset");
362
status = EX_OSERR;
363
goto failure;
364
}
365
ret = sigaddset(&new_action.sa_mask, SIGTERM);
366
if(ret == -1){
367
error_plus(0, errno, "sigaddset");
368
status = EX_OSERR;
369
goto failure;
370
}
371
ret = sigaction(SIGINT, NULL, &old_action);
372
if(ret == -1){
373
if(errno != EINTR){
374
error_plus(0, errno, "sigaction");
375
status = EX_OSERR;
376
}
377
goto failure;
378
}
379
if(old_action.sa_handler != SIG_IGN){
380
ret = sigaction(SIGINT, &new_action, NULL);
381
if(ret == -1){
382
if(errno != EINTR){
383
error_plus(0, errno, "sigaction");
384
status = EX_OSERR;
385
}
386
goto failure;
387
}
388
}
389
ret = sigaction(SIGHUP, NULL, &old_action);
390
if(ret == -1){
391
if(errno != EINTR){
392
error_plus(0, errno, "sigaction");
393
status = EX_OSERR;
394
}
395
goto failure;
396
}
397
if(old_action.sa_handler != SIG_IGN){
398
ret = sigaction(SIGHUP, &new_action, NULL);
399
if(ret == -1){
400
if(errno != EINTR){
401
error_plus(0, errno, "sigaction");
402
status = EX_OSERR;
403
}
404
goto failure;
405
}
406
}
407
ret = sigaction(SIGTERM, NULL, &old_action);
408
if(ret == -1){
409
if(errno != EINTR){
410
error_plus(0, errno, "sigaction");
411
status = EX_OSERR;
412
}
413
goto failure;
414
}
415
if(old_action.sa_handler != SIG_IGN){
416
ret = sigaction(SIGTERM, &new_action, NULL);
417
if(ret == -1){
418
if(errno != EINTR){
419
error_plus(0, errno, "sigaction");
420
status = EX_OSERR;
421
}
422
goto failure;
423
}
424
}
425
}
426
427
usplash_accessed = true;
428
/* Write command to FIFO */
429
if(not usplash_write(&fifo_fd, "TIMEOUT", "0")){
430
if(errno != EINTR){
431
error_plus(0, errno, "usplash_write");
432
status = EX_OSERR;
433
}
434
goto failure;
435
}
436
437
if(interrupted_by_signal){
438
goto failure;
439
}
440
441
if(not usplash_write(&fifo_fd, "INPUTQUIET", prompt)){
442
if(errno != EINTR){
443
error_plus(0, errno, "usplash_write");
444
status = EX_OSERR;
445
}
446
goto failure;
447
}
448
449
if(interrupted_by_signal){
450
goto failure;
451
}
452
453
free(prompt);
454
prompt = NULL;
455
456
/* Read reply from usplash */
457
/* Open FIFO */
458
outfifo_fd = open("/dev/.initramfs/usplash_outfifo", O_RDONLY);
459
if(outfifo_fd == -1){
460
if(errno != EINTR){
461
error_plus(0, errno, "open");
462
status = EX_OSERR;
463
}
464
goto failure;
465
}
466
467
if(interrupted_by_signal){
468
goto failure;
469
}
470
471
/* Read from FIFO */
472
size_t buf_allocated = 0;
473
const size_t blocksize = 1024;
474
do {
475
/* Allocate more space */
476
if(buf_len + blocksize > buf_allocated){
477
char *tmp = realloc(buf, buf_allocated + blocksize);
478
if(tmp == NULL){
479
if(errno != EINTR){
480
error_plus(0, errno, "realloc");
481
status = EX_OSERR;
482
}
483
goto failure;
484
}
485
buf = tmp;
486
buf_allocated += blocksize;
487
}
488
sret = read(outfifo_fd, buf + buf_len,
489
buf_allocated - buf_len);
490
if(sret == -1){
491
if(errno != EINTR){
492
error_plus(0, errno, "read");
493
status = EX_OSERR;
494
}
495
close(outfifo_fd);
496
goto failure;
497
}
498
if(interrupted_by_signal){
499
break;
500
}
501
502
buf_len += (size_t)sret;
503
} while(sret != 0);
504
ret = close(outfifo_fd);
505
if(ret == -1){
506
if(errno != EINTR){
507
error_plus(0, errno, "close");
508
status = EX_OSERR;
509
}
510
goto failure;
511
}
512
outfifo_fd = -1;
513
514
if(interrupted_by_signal){
515
goto failure;
516
}
517
518
if(not usplash_write(&fifo_fd, "TIMEOUT", "15")){
519
if(errno != EINTR){
520
error_plus(0, errno, "usplash_write");
521
status = EX_OSERR;
522
}
523
goto failure;
524
}
525
526
if(interrupted_by_signal){
527
goto failure;
528
}
529
530
ret = close(fifo_fd);
531
if(ret == -1){
532
if(errno != EINTR){
533
error_plus(0, errno, "close");
534
status = EX_OSERR;
535
}
536
goto failure;
537
}
538
fifo_fd = -1;
539
540
/* Print password to stdout */
541
size_t written = 0;
542
while(written < buf_len){
543
do {
544
sret = write(STDOUT_FILENO, buf + written, buf_len - written);
545
if(sret == -1){
546
if(errno != EINTR){
547
error_plus(0, errno, "write");
548
status = EX_OSERR;
549
}
550
goto failure;
551
}
552
} while(sret == -1);
553
554
if(interrupted_by_signal){
555
goto failure;
556
}
557
written += (size_t)sret;
558
}
559
free(buf);
560
buf = NULL;
561
562
if(interrupted_by_signal){
563
goto failure;
564
}
565
566
free(cmdline);
567
return EXIT_SUCCESS;
568
569
failure:
570
571
free(buf);
572
573
free(prompt);
574
575
/* If usplash was never accessed, we can stop now */
576
if(not usplash_accessed){
577
return status;
578
}
579
580
/* Close FIFO */
581
if(fifo_fd != -1){
582
ret = close(fifo_fd);
583
if(ret == -1 and errno != EINTR){
584
error_plus(0, errno, "close");
585
}
586
fifo_fd = -1;
587
}
588
589
/* Close output FIFO */
590
if(outfifo_fd != -1){
591
ret = close(outfifo_fd);
592
if(ret == -1){
593
error_plus(0, errno, "close");
594
}
595
}
596
597
/* Create argv for new usplash*/
598
char **cmdline_argv = malloc((argz_count(cmdline, cmdline_len) + 1)
599
* sizeof(char *)); /* Count args */
600
if(cmdline_argv == NULL){
601
error_plus(0, errno, "malloc");
602
return status;
603
}
604
argz_extract(cmdline, cmdline_len, cmdline_argv); /* Create argv */
605
606
/* Kill old usplash */
607
kill(usplash_pid, SIGTERM);
608
sleep(2);
609
while(kill(usplash_pid, 0) == 0){
610
kill(usplash_pid, SIGKILL);
611
sleep(1);
612
}
613
614
pid_t new_usplash_pid = fork();
615
if(new_usplash_pid == 0){
616
/* Child; will become new usplash process */
617
618
/* Make the effective user ID (root) the only user ID instead of
619
the real user ID (_mandos) */
620
ret = setuid(geteuid());
621
if(ret == -1){
622
error_plus(0, errno, "setuid");
623
}
624
625
setsid();
626
ret = chdir("/");
627
if(ret == -1){
628
error_plus(0, errno, "chdir");
629
_exit(EX_OSERR);
630
}
631
/* if(fork() != 0){ */
632
/* _exit(EXIT_SUCCESS); */
633
/* } */
634
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
635
if(ret == -1){
636
error_plus(0, errno, "dup2");
637
_exit(EX_OSERR);
638
}
639
640
execv(usplash_name, cmdline_argv);
641
if(not interrupted_by_signal){
642
error_plus(0, errno, "execv");
643
}
644
free(cmdline);
645
free(cmdline_argv);
646
_exit(EX_OSERR);
647
}
648
free(cmdline);
649
free(cmdline_argv);
650
sleep(2);
651
if(not usplash_write(&fifo_fd, "PULSATE", NULL)){
652
if(errno != EINTR){
653
error_plus(0, errno, "usplash_write");
654
}
655
}
656
657
/* Close FIFO (again) */
658
if(fifo_fd != -1){
659
ret = close(fifo_fd);
660
if(ret == -1 and errno != EINTR){
661
error_plus(0, errno, "close");
662
}
663
fifo_fd = -1;
664
}
665
666
if(interrupted_by_signal){
667
struct sigaction signal_action = { .sa_handler = SIG_DFL };
668
sigemptyset(&signal_action.sa_mask);
669
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
670
&signal_action, NULL));
671
if(ret == -1){
672
error_plus(0, errno, "sigaction");
673
}
674
do {
675
ret = raise(signal_received);
676
} while(ret != 0 and errno == EINTR);
677
if(ret != 0){
678
error_plus(0, errno, "raise");
679
abort();
680
}
681
TEMP_FAILURE_RETRY(pause());
682
}
683
684
return status;
685
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0