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- Committer: Teddy Hogeborn
- Date: 2009-09-07 07:48:59 UTC
- mto: (24.1.140 mandos) (237.12.2 mandos-persistent) (299.1.1 release) (300.1.1 release) (301.1.1 release)
- mto: This revision was merged to the branch mainline in revision 264.
- Revision ID: teddy@fukt.bsnet.se-20090907074859-nv2nni1wwib5hi10
* plugin-runner.c: Minor stylistic changes.
* plugins.d/askpass-fifo.c: Changed contact information and did minor
stylistic changes.
* plugins.d/mandos-client.c: Minor stylistic changes.
* plugins.d/password-prompt.c: Changed contact information.
* plugins.d/splashy.c: Changed contact information.
(main): Changed error handling design. Bug fix: Will now be much
more tolerant against signals. Bug fix: Will now re-raise
signal received.
* plugins.d/usplash.c: Changed contact information and did minor
stylistic changes.
* plugins.d/askpass-fifo.c: Changed contact information and did minor
stylistic changes.
* plugins.d/mandos-client.c: Minor stylistic changes.
* plugins.d/password-prompt.c: Changed contact information.
* plugins.d/splashy.c: Changed contact information.
(main): Changed error handling design. Bug fix: Will now be much
more tolerant against signals. Bug fix: Will now re-raise
signal received.
* plugins.d/usplash.c: Changed contact information and did minor
stylistic changes.
- files added:
- .bzr-builddeb
- debian
- debian/po
- plugins.d
- files removed:
- bad-ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- files modified:
- Makefile
added
removed
plugin-runner.c
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
7
*
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
12
*
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
*
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf() */
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
EXIT_SUCCESS, realloc() */
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
36
uid_t, gid_t, getuid(), getgid(),
37
dirfd() */
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
FD_SET(), FD_ISSET(), FD_CLR */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
42
WCOREDUMP() */
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, opendir(),
46
readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
50
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
53
close() */
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
FD_CLOEXEC */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal() */
58
#include <errno.h> /* errno */
59
#include <argp.h> /* struct argp_option, struct
60
argp_state, struct argp,
61
argp_parse(), ARGP_ERR_UNKNOWN,
62
ARGP_KEY_END, ARGP_KEY_ARG,
63
error_t */
64
#include <signal.h> /* struct sigaction, sigemptyset(),
65
sigaddset(), sigaction(),
66
sigprocmask(), SIG_BLOCK, SIGCHLD,
67
SIG_UNBLOCK, kill(), sig_atomic_t
68
*/
69
#include <errno.h> /* errno, EBADF */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
71
72
#define BUFFER_SIZE 256
73
74
#define PDIR "/lib/mandos/plugins.d"
75
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
76
77
const char *argp_program_version = "plugin-runner " VERSION;
78
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
79
80
typedef struct plugin{
81
char *name; /* can be NULL or any plugin name */
82
char **argv;
83
int argc;
84
char **environ;
85
int envc;
86
bool disabled;
87
88
/* Variables used for running processes*/
89
pid_t pid;
90
int fd;
91
char *buffer;
92
size_t buffer_size;
93
size_t buffer_length;
94
bool eof;
95
volatile sig_atomic_t completed;
96
int status;
97
struct plugin *next;
98
} plugin;
99
100
static plugin *plugin_list = NULL;
101
102
/* Gets an existing plugin based on name,
103
or if none is found, creates a new one */
104
static plugin *getplugin(char *name){
105
/* Check for exiting plugin with that name */
106
for(plugin *p = plugin_list; p != NULL; p = p->next){
107
if((p->name == name)
108
or (p->name and name and (strcmp(p->name, name) == 0))){
109
return p;
110
}
111
}
112
/* Create a new plugin */
113
plugin *new_plugin = NULL;
114
do {
115
new_plugin = malloc(sizeof(plugin));
116
} while(new_plugin == NULL and errno == EINTR);
117
if(new_plugin == NULL){
118
return NULL;
119
}
120
char *copy_name = NULL;
121
if(name != NULL){
122
do {
123
copy_name = strdup(name);
124
} while(copy_name == NULL and errno == EINTR);
125
if(copy_name == NULL){
126
free(new_plugin);
127
return NULL;
128
}
129
}
130
131
*new_plugin = (plugin){ .name = copy_name,
132
.argc = 1,
133
.disabled = false,
134
.next = plugin_list };
135
136
do {
137
new_plugin->argv = malloc(sizeof(char *) * 2);
138
} while(new_plugin->argv == NULL and errno == EINTR);
139
if(new_plugin->argv == NULL){
140
free(copy_name);
141
free(new_plugin);
142
return NULL;
143
}
144
new_plugin->argv[0] = copy_name;
145
new_plugin->argv[1] = NULL;
146
147
do {
148
new_plugin->environ = malloc(sizeof(char *));
149
} while(new_plugin->environ == NULL and errno == EINTR);
150
if(new_plugin->environ == NULL){
151
free(copy_name);
152
free(new_plugin->argv);
153
free(new_plugin);
154
return NULL;
155
}
156
new_plugin->environ[0] = NULL;
157
158
/* Append the new plugin to the list */
159
plugin_list = new_plugin;
160
return new_plugin;
161
}
162
163
/* Helper function for add_argument and add_environment */
164
static bool add_to_char_array(const char *new, char ***array,
165
int *len){
166
/* Resize the pointed-to array to hold one more pointer */
167
do {
168
*array = realloc(*array, sizeof(char *)
169
* (size_t) ((*len) + 2));
170
} while(*array == NULL and errno == EINTR);
171
/* Malloc check */
172
if(*array == NULL){
173
return false;
174
}
175
/* Make a copy of the new string */
176
char *copy;
177
do {
178
copy = strdup(new);
179
} while(copy == NULL and errno == EINTR);
180
if(copy == NULL){
181
return false;
182
}
183
/* Insert the copy */
184
(*array)[*len] = copy;
185
(*len)++;
186
/* Add a new terminating NULL pointer to the last element */
187
(*array)[*len] = NULL;
188
return true;
189
}
190
191
/* Add to a plugin's argument vector */
192
static bool add_argument(plugin *p, const char *arg){
193
if(p == NULL){
194
return false;
195
}
196
return add_to_char_array(arg, &(p->argv), &(p->argc));
197
}
198
199
/* Add to a plugin's environment */
200
static bool add_environment(plugin *p, const char *def, bool replace){
201
if(p == NULL){
202
return false;
203
}
204
/* namelen = length of name of environment variable */
205
size_t namelen = (size_t)(strchrnul(def, '=') - def);
206
/* Search for this environment variable */
207
for(char **e = p->environ; *e != NULL; e++){
208
if(strncmp(*e, def, namelen + 1) == 0){
209
/* It already exists */
210
if(replace){
211
char *new;
212
do {
213
new = realloc(*e, strlen(def) + 1);
214
} while(new == NULL and errno == EINTR);
215
if(new == NULL){
216
return false;
217
}
218
*e = new;
219
strcpy(*e, def);
220
}
221
return true;
222
}
223
}
224
return add_to_char_array(def, &(p->environ), &(p->envc));
225
}
226
227
/*
228
* Based on the example in the GNU LibC manual chapter 13.13 "File
229
* Descriptor Flags".
230
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
231
*/
232
static int set_cloexec_flag(int fd){
233
int ret = TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
234
/* If reading the flags failed, return error indication now. */
235
if(ret < 0){
236
return ret;
237
}
238
/* Store modified flag word in the descriptor. */
239
return TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD, ret | FD_CLOEXEC));
240
}
241
242
243
/* Mark processes as completed when they exit, and save their exit
244
status. */
245
static void handle_sigchld(__attribute__((unused)) int sig){
246
int old_errno = errno;
247
while(true){
248
plugin *proc = plugin_list;
249
int status;
250
pid_t pid = waitpid(-1, &status, WNOHANG);
251
if(pid == 0){
252
/* Only still running child processes */
253
break;
254
}
255
if(pid == -1){
256
if(errno == ECHILD){
257
/* No child processes */
258
break;
259
}
260
perror("waitpid");
261
}
262
263
/* A child exited, find it in process_list */
264
while(proc != NULL and proc->pid != pid){
265
proc = proc->next;
266
}
267
if(proc == NULL){
268
/* Process not found in process list */
269
continue;
270
}
271
proc->status = status;
272
proc->completed = 1;
273
}
274
errno = old_errno;
275
}
276
277
/* Prints out a password to stdout */
278
static bool print_out_password(const char *buffer, size_t length){
279
ssize_t ret;
280
for(size_t written = 0; written < length; written += (size_t)ret){
281
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
282
length - written));
283
if(ret < 0){
284
return false;
285
}
286
}
287
return true;
288
}
289
290
/* Removes and free a plugin from the plugin list */
291
static void free_plugin(plugin *plugin_node){
292
293
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
294
free(*arg);
295
}
296
free(plugin_node->argv);
297
for(char **env = plugin_node->environ; *env != NULL; env++){
298
free(*env);
299
}
300
free(plugin_node->environ);
301
free(plugin_node->buffer);
302
303
/* Removes the plugin from the singly-linked list */
304
if(plugin_node == plugin_list){
305
/* First one - simple */
306
plugin_list = plugin_list->next;
307
} else {
308
/* Second one or later */
309
for(plugin *p = plugin_list; p != NULL; p = p->next){
310
if(p->next == plugin_node){
311
p->next = plugin_node->next;
312
break;
313
}
314
}
315
}
316
317
free(plugin_node);
318
}
319
320
static void free_plugin_list(void){
321
while(plugin_list != NULL){
322
free_plugin(plugin_list);
323
}
324
}
325
326
int main(int argc, char *argv[]){
327
char *plugindir = NULL;
328
char *argfile = NULL;
329
FILE *conffp;
330
size_t d_name_len;
331
DIR *dir = NULL;
332
struct dirent *dirst;
333
struct stat st;
334
fd_set rfds_all;
335
int ret, maxfd = 0;
336
ssize_t sret;
337
uid_t uid = 65534;
338
gid_t gid = 65534;
339
bool debug = false;
340
int exitstatus = EXIT_SUCCESS;
341
struct sigaction old_sigchld_action;
342
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
343
.sa_flags = SA_NOCLDSTOP };
344
char **custom_argv = NULL;
345
int custom_argc = 0;
346
347
/* Establish a signal handler */
348
sigemptyset(&sigchld_action.sa_mask);
349
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
350
if(ret == -1){
351
perror("sigaddset");
352
exitstatus = EXIT_FAILURE;
353
goto fallback;
354
}
355
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
356
if(ret == -1){
357
perror("sigaction");
358
exitstatus = EXIT_FAILURE;
359
goto fallback;
360
}
361
362
/* The options we understand. */
363
struct argp_option options[] = {
364
{ .name = "global-options", .key = 'g',
365
.arg = "OPTION[,OPTION[,...]]",
366
.doc = "Options passed to all plugins" },
367
{ .name = "global-env", .key = 'G',
368
.arg = "VAR=value",
369
.doc = "Environment variable passed to all plugins" },
370
{ .name = "options-for", .key = 'o',
371
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
372
.doc = "Options passed only to specified plugin" },
373
{ .name = "env-for", .key = 'E',
374
.arg = "PLUGIN:ENV=value",
375
.doc = "Environment variable passed to specified plugin" },
376
{ .name = "disable", .key = 'd',
377
.arg = "PLUGIN",
378
.doc = "Disable a specific plugin", .group = 1 },
379
{ .name = "enable", .key = 'e',
380
.arg = "PLUGIN",
381
.doc = "Enable a specific plugin", .group = 1 },
382
{ .name = "plugin-dir", .key = 128,
383
.arg = "DIRECTORY",
384
.doc = "Specify a different plugin directory", .group = 2 },
385
{ .name = "config-file", .key = 129,
386
.arg = "FILE",
387
.doc = "Specify a different configuration file", .group = 2 },
388
{ .name = "userid", .key = 130,
389
.arg = "ID", .flags = 0,
390
.doc = "User ID the plugins will run as", .group = 3 },
391
{ .name = "groupid", .key = 131,
392
.arg = "ID", .flags = 0,
393
.doc = "Group ID the plugins will run as", .group = 3 },
394
{ .name = "debug", .key = 132,
395
.doc = "Debug mode", .group = 4 },
396
{ .name = NULL }
397
};
398
399
error_t parse_opt(int key, char *arg, __attribute__((unused))
400
struct argp_state *state){
401
switch(key){
402
char *tmp;
403
intmax_t tmpmax;
404
case 'g': /* --global-options */
405
if(arg != NULL){
406
char *plugin_option;
407
while((plugin_option = strsep(&arg, ",")) != NULL){
408
if(plugin_option[0] == '\0'){
409
continue;
410
}
411
if(not add_argument(getplugin(NULL), plugin_option)){
412
perror("add_argument");
413
return ARGP_ERR_UNKNOWN;
414
}
415
}
416
}
417
break;
418
case 'G': /* --global-env */
419
if(arg == NULL){
420
break;
421
}
422
if(not add_environment(getplugin(NULL), arg, true)){
423
perror("add_environment");
424
}
425
break;
426
case 'o': /* --options-for */
427
if(arg != NULL){
428
char *plugin_name = strsep(&arg, ":");
429
if(plugin_name[0] == '\0'){
430
break;
431
}
432
char *plugin_option;
433
while((plugin_option = strsep(&arg, ",")) != NULL){
434
if(not add_argument(getplugin(plugin_name), plugin_option)){
435
perror("add_argument");
436
return ARGP_ERR_UNKNOWN;
437
}
438
}
439
}
440
break;
441
case 'E': /* --env-for */
442
if(arg == NULL){
443
break;
444
}
445
{
446
char *envdef = strchr(arg, ':');
447
if(envdef == NULL){
448
break;
449
}
450
*envdef = '\0';
451
if(not add_environment(getplugin(arg), envdef+1, true)){
452
perror("add_environment");
453
}
454
}
455
break;
456
case 'd': /* --disable */
457
if(arg != NULL){
458
plugin *p = getplugin(arg);
459
if(p == NULL){
460
return ARGP_ERR_UNKNOWN;
461
}
462
p->disabled = true;
463
}
464
break;
465
case 'e': /* --enable */
466
if(arg != NULL){
467
plugin *p = getplugin(arg);
468
if(p == NULL){
469
return ARGP_ERR_UNKNOWN;
470
}
471
p->disabled = false;
472
}
473
break;
474
case 128: /* --plugin-dir */
475
free(plugindir);
476
plugindir = strdup(arg);
477
if(plugindir == NULL){
478
perror("strdup");
479
}
480
break;
481
case 129: /* --config-file */
482
/* This is already done by parse_opt_config_file() */
483
break;
484
case 130: /* --userid */
485
errno = 0;
486
tmpmax = strtoimax(arg, &tmp, 10);
487
if(errno != 0 or tmp == arg or *tmp != '\0'
488
or tmpmax != (uid_t)tmpmax){
489
fprintf(stderr, "Bad user ID number: \"%s\", using %"
490
PRIdMAX "\n", arg, (intmax_t)uid);
491
} else {
492
uid = (uid_t)tmpmax;
493
}
494
break;
495
case 131: /* --groupid */
496
errno = 0;
497
tmpmax = strtoimax(arg, &tmp, 10);
498
if(errno != 0 or tmp == arg or *tmp != '\0'
499
or tmpmax != (gid_t)tmpmax){
500
fprintf(stderr, "Bad group ID number: \"%s\", using %"
501
PRIdMAX "\n", arg, (intmax_t)gid);
502
} else {
503
gid = (gid_t)tmpmax;
504
}
505
break;
506
case 132: /* --debug */
507
debug = true;
508
break;
509
/*
510
* When adding more options before this line, remember to also add a
511
* "case" to the "parse_opt_config_file" function below.
512
*/
513
case ARGP_KEY_ARG:
514
/* Cryptsetup always passes an argument, which is an empty
515
string if "none" was specified in /etc/crypttab. So if
516
argument was empty, we ignore it silently. */
517
if(arg[0] != '\0'){
518
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
519
}
520
break;
521
case ARGP_KEY_END:
522
break;
523
default:
524
return ARGP_ERR_UNKNOWN;
525
}
526
return 0;
527
}
528
529
/* This option parser is the same as parse_opt() above, except it
530
ignores everything but the --config-file option. */
531
error_t parse_opt_config_file(int key, char *arg,
532
__attribute__((unused))
533
struct argp_state *state){
534
switch(key){
535
case 'g': /* --global-options */
536
case 'G': /* --global-env */
537
case 'o': /* --options-for */
538
case 'E': /* --env-for */
539
case 'd': /* --disable */
540
case 'e': /* --enable */
541
case 128: /* --plugin-dir */
542
break;
543
case 129: /* --config-file */
544
free(argfile);
545
argfile = strdup(arg);
546
if(argfile == NULL){
547
perror("strdup");
548
}
549
break;
550
case 130: /* --userid */
551
case 131: /* --groupid */
552
case 132: /* --debug */
553
case ARGP_KEY_ARG:
554
case ARGP_KEY_END:
555
break;
556
default:
557
return ARGP_ERR_UNKNOWN;
558
}
559
return 0;
560
}
561
562
struct argp argp = { .options = options,
563
.parser = parse_opt_config_file,
564
.args_doc = "",
565
.doc = "Mandos plugin runner -- Run plugins" };
566
567
/* Parse using parse_opt_config_file() in order to get the custom
568
config file location, if any. */
569
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
570
if(ret == ARGP_ERR_UNKNOWN){
571
fprintf(stderr, "Unknown error while parsing arguments\n");
572
exitstatus = EXIT_FAILURE;
573
goto fallback;
574
}
575
576
/* Reset to the normal argument parser */
577
argp.parser = parse_opt;
578
579
/* Open the configfile if available */
580
if(argfile == NULL){
581
conffp = fopen(AFILE, "r");
582
} else {
583
conffp = fopen(argfile, "r");
584
}
585
if(conffp != NULL){
586
char *org_line = NULL;
587
char *p, *arg, *new_arg, *line;
588
size_t size = 0;
589
const char whitespace_delims[] = " \r\t\f\v\n";
590
const char comment_delim[] = "#";
591
592
custom_argc = 1;
593
custom_argv = malloc(sizeof(char*) * 2);
594
if(custom_argv == NULL){
595
perror("malloc");
596
exitstatus = EXIT_FAILURE;
597
goto fallback;
598
}
599
custom_argv[0] = argv[0];
600
custom_argv[1] = NULL;
601
602
/* for each line in the config file, strip whitespace and ignore
603
commented text */
604
while(true){
605
sret = getline(&org_line, &size, conffp);
606
if(sret == -1){
607
break;
608
}
609
610
line = org_line;
611
arg = strsep(&line, comment_delim);
612
while((p = strsep(&arg, whitespace_delims)) != NULL){
613
if(p[0] == '\0'){
614
continue;
615
}
616
new_arg = strdup(p);
617
if(new_arg == NULL){
618
perror("strdup");
619
exitstatus = EXIT_FAILURE;
620
free(org_line);
621
goto fallback;
622
}
623
624
custom_argc += 1;
625
custom_argv = realloc(custom_argv, sizeof(char *)
626
* ((unsigned int) custom_argc + 1));
627
if(custom_argv == NULL){
628
perror("realloc");
629
exitstatus = EXIT_FAILURE;
630
free(org_line);
631
goto fallback;
632
}
633
custom_argv[custom_argc-1] = new_arg;
634
custom_argv[custom_argc] = NULL;
635
}
636
}
637
do {
638
ret = fclose(conffp);
639
} while(ret == EOF and errno == EINTR);
640
if(ret == EOF){
641
perror("fclose");
642
exitstatus = EXIT_FAILURE;
643
goto fallback;
644
}
645
free(org_line);
646
} else {
647
/* Check for harmful errors and go to fallback. Other errors might
648
not affect opening plugins */
649
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
650
perror("fopen");
651
exitstatus = EXIT_FAILURE;
652
goto fallback;
653
}
654
}
655
/* If there was any arguments from configuration file,
656
pass them to parser as command arguments */
657
if(custom_argv != NULL){
658
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
659
0, NULL);
660
if(ret == ARGP_ERR_UNKNOWN){
661
fprintf(stderr, "Unknown error while parsing arguments\n");
662
exitstatus = EXIT_FAILURE;
663
goto fallback;
664
}
665
}
666
667
/* Parse actual command line arguments, to let them override the
668
config file */
669
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
670
if(ret == ARGP_ERR_UNKNOWN){
671
fprintf(stderr, "Unknown error while parsing arguments\n");
672
exitstatus = EXIT_FAILURE;
673
goto fallback;
674
}
675
676
if(debug){
677
for(plugin *p = plugin_list; p != NULL; p=p->next){
678
fprintf(stderr, "Plugin: %s has %d arguments\n",
679
p->name ? p->name : "Global", p->argc - 1);
680
for(char **a = p->argv; *a != NULL; a++){
681
fprintf(stderr, "\tArg: %s\n", *a);
682
}
683
fprintf(stderr, "...and %d environment variables\n", p->envc);
684
for(char **a = p->environ; *a != NULL; a++){
685
fprintf(stderr, "\t%s\n", *a);
686
}
687
}
688
}
689
690
/* Strip permissions down to nobody */
691
setgid(gid);
692
if(ret == -1){
693
perror("setgid");
694
}
695
ret = setuid(uid);
696
if(ret == -1){
697
perror("setuid");
698
}
699
700
if(plugindir == NULL){
701
dir = opendir(PDIR);
702
} else {
703
dir = opendir(plugindir);
704
}
705
706
if(dir == NULL){
707
perror("Could not open plugin dir");
708
exitstatus = EXIT_FAILURE;
709
goto fallback;
710
}
711
712
/* Set the FD_CLOEXEC flag on the directory, if possible */
713
{
714
int dir_fd = dirfd(dir);
715
if(dir_fd >= 0){
716
ret = set_cloexec_flag(dir_fd);
717
if(ret < 0){
718
perror("set_cloexec_flag");
719
exitstatus = EXIT_FAILURE;
720
goto fallback;
721
}
722
}
723
}
724
725
FD_ZERO(&rfds_all);
726
727
/* Read and execute any executable in the plugin directory*/
728
while(true){
729
do {
730
dirst = readdir(dir);
731
} while(dirst == NULL and errno == EINTR);
732
733
/* All directory entries have been processed */
734
if(dirst == NULL){
735
if(errno == EBADF){
736
perror("readdir");
737
exitstatus = EXIT_FAILURE;
738
goto fallback;
739
}
740
break;
741
}
742
743
d_name_len = strlen(dirst->d_name);
744
745
/* Ignore dotfiles, backup files and other junk */
746
{
747
bool bad_name = false;
748
749
const char const *bad_prefixes[] = { ".", "#", NULL };
750
751
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
752
".dpkg-old",
753
".dpkg-bak",
754
".dpkg-divert", NULL };
755
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
756
size_t pre_len = strlen(*pre);
757
if((d_name_len >= pre_len)
758
and strncmp((dirst->d_name), *pre, pre_len) == 0){
759
if(debug){
760
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
761
" with bad prefix %s\n", dirst->d_name, *pre);
762
}
763
bad_name = true;
764
break;
765
}
766
}
767
if(bad_name){
768
continue;
769
}
770
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
771
size_t suf_len = strlen(*suf);
772
if((d_name_len >= suf_len)
773
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
774
== 0)){
775
if(debug){
776
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
777
" with bad suffix %s\n", dirst->d_name, *suf);
778
}
779
bad_name = true;
780
break;
781
}
782
}
783
784
if(bad_name){
785
continue;
786
}
787
}
788
789
char *filename;
790
if(plugindir == NULL){
791
ret = TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
792
dirst->d_name));
793
} else {
794
ret = TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s", plugindir,
795
dirst->d_name));
796
}
797
if(ret < 0){
798
perror("asprintf");
799
continue;
800
}
801
802
ret = TEMP_FAILURE_RETRY(stat(filename, &st));
803
if(ret == -1){
804
perror("stat");
805
free(filename);
806
continue;
807
}
808
809
/* Ignore non-executable files */
810
if(not S_ISREG(st.st_mode)
811
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
812
if(debug){
813
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
814
" with bad type or mode\n", filename);
815
}
816
free(filename);
817
continue;
818
}
819
820
plugin *p = getplugin(dirst->d_name);
821
if(p == NULL){
822
perror("getplugin");
823
free(filename);
824
continue;
825
}
826
if(p->disabled){
827
if(debug){
828
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
829
dirst->d_name);
830
}
831
free(filename);
832
continue;
833
}
834
{
835
/* Add global arguments to argument list for this plugin */
836
plugin *g = getplugin(NULL);
837
if(g != NULL){
838
for(char **a = g->argv + 1; *a != NULL; a++){
839
if(not add_argument(p, *a)){
840
perror("add_argument");
841
}
842
}
843
/* Add global environment variables */
844
for(char **e = g->environ; *e != NULL; e++){
845
if(not add_environment(p, *e, false)){
846
perror("add_environment");
847
}
848
}
849
}
850
}
851
/* If this plugin has any environment variables, we will call
852
using execve and need to duplicate the environment from this
853
process, too. */
854
if(p->environ[0] != NULL){
855
for(char **e = environ; *e != NULL; e++){
856
if(not add_environment(p, *e, false)){
857
perror("add_environment");
858
}
859
}
860
}
861
862
int pipefd[2];
863
ret = TEMP_FAILURE_RETRY(pipe(pipefd));
864
if(ret == -1){
865
perror("pipe");
866
exitstatus = EXIT_FAILURE;
867
goto fallback;
868
}
869
/* Ask OS to automatic close the pipe on exec */
870
ret = set_cloexec_flag(pipefd[0]);
871
if(ret < 0){
872
perror("set_cloexec_flag");
873
exitstatus = EXIT_FAILURE;
874
goto fallback;
875
}
876
ret = set_cloexec_flag(pipefd[1]);
877
if(ret < 0){
878
perror("set_cloexec_flag");
879
exitstatus = EXIT_FAILURE;
880
goto fallback;
881
}
882
/* Block SIGCHLD until process is safely in process list */
883
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
884
&sigchld_action.sa_mask,
885
NULL));
886
if(ret < 0){
887
perror("sigprocmask");
888
exitstatus = EXIT_FAILURE;
889
goto fallback;
890
}
891
/* Starting a new process to be watched */
892
pid_t pid;
893
do {
894
pid = fork();
895
} while(pid == -1 and errno == EINTR);
896
if(pid == -1){
897
perror("fork");
898
exitstatus = EXIT_FAILURE;
899
goto fallback;
900
}
901
if(pid == 0){
902
/* this is the child process */
903
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
904
if(ret < 0){
905
perror("sigaction");
906
_exit(EXIT_FAILURE);
907
}
908
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
909
if(ret < 0){
910
perror("sigprocmask");
911
_exit(EXIT_FAILURE);
912
}
913
914
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
915
if(ret == -1){
916
perror("dup2");
917
_exit(EXIT_FAILURE);
918
}
919
920
if(dirfd(dir) < 0){
921
/* If dir has no file descriptor, we could not set FD_CLOEXEC
922
above and must now close it manually here. */
923
closedir(dir);
924
}
925
if(p->environ[0] == NULL){
926
if(execv(filename, p->argv) < 0){
927
perror("execv");
928
_exit(EXIT_FAILURE);
929
}
930
} else {
931
if(execve(filename, p->argv, p->environ) < 0){
932
perror("execve");
933
_exit(EXIT_FAILURE);
934
}
935
}
936
/* no return */
937
}
938
/* Parent process */
939
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
940
pipe */
941
free(filename);
942
plugin *new_plugin = getplugin(dirst->d_name);
943
if(new_plugin == NULL){
944
perror("getplugin");
945
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
946
&sigchld_action.sa_mask,
947
NULL));
948
if(ret < 0){
949
perror("sigprocmask");
950
}
951
exitstatus = EXIT_FAILURE;
952
goto fallback;
953
}
954
955
new_plugin->pid = pid;
956
new_plugin->fd = pipefd[0];
957
958
/* Unblock SIGCHLD so signal handler can be run if this process
959
has already completed */
960
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
961
&sigchld_action.sa_mask,
962
NULL));
963
if(ret < 0){
964
perror("sigprocmask");
965
exitstatus = EXIT_FAILURE;
966
goto fallback;
967
}
968
969
FD_SET(new_plugin->fd, &rfds_all);
970
971
if(maxfd < new_plugin->fd){
972
maxfd = new_plugin->fd;
973
}
974
}
975
976
TEMP_FAILURE_RETRY(closedir(dir));
977
dir = NULL;
978
free_plugin(getplugin(NULL));
979
980
for(plugin *p = plugin_list; p != NULL; p = p->next){
981
if(p->pid != 0){
982
break;
983
}
984
if(p->next == NULL){
985
fprintf(stderr, "No plugin processes started. Incorrect plugin"
986
" directory?\n");
987
free_plugin_list();
988
}
989
}
990
991
/* Main loop while running plugins exist */
992
while(plugin_list){
993
fd_set rfds = rfds_all;
994
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
995
if(select_ret == -1 and errno != EINTR){
996
perror("select");
997
exitstatus = EXIT_FAILURE;
998
goto fallback;
999
}
1000
/* OK, now either a process completed, or something can be read
1001
from one of them */
1002
for(plugin *proc = plugin_list; proc != NULL;){
1003
/* Is this process completely done? */
1004
if(proc->completed and proc->eof){
1005
/* Only accept the plugin output if it exited cleanly */
1006
if(not WIFEXITED(proc->status)
1007
or WEXITSTATUS(proc->status) != 0){
1008
/* Bad exit by plugin */
1009
1010
if(debug){
1011
if(WIFEXITED(proc->status)){
1012
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1013
" status %d\n", proc->name,
1014
(intmax_t) (proc->pid),
1015
WEXITSTATUS(proc->status));
1016
} else if(WIFSIGNALED(proc->status)){
1017
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1018
" signal %d: %s\n", proc->name,
1019
(intmax_t) (proc->pid),
1020
WTERMSIG(proc->status),
1021
strsignal(WTERMSIG(proc->status)));
1022
} else if(WCOREDUMP(proc->status)){
1023
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1024
" core\n", proc->name, (intmax_t) (proc->pid));
1025
}
1026
}
1027
1028
/* Remove the plugin */
1029
FD_CLR(proc->fd, &rfds_all);
1030
1031
/* Block signal while modifying process_list */
1032
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1033
&sigchld_action.sa_mask,
1034
NULL));
1035
if(ret < 0){
1036
perror("sigprocmask");
1037
exitstatus = EXIT_FAILURE;
1038
goto fallback;
1039
}
1040
1041
plugin *next_plugin = proc->next;
1042
free_plugin(proc);
1043
proc = next_plugin;
1044
1045
/* We are done modifying process list, so unblock signal */
1046
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1047
&sigchld_action.sa_mask,
1048
NULL));
1049
if(ret < 0){
1050
perror("sigprocmask");
1051
exitstatus = EXIT_FAILURE;
1052
goto fallback;
1053
}
1054
1055
if(plugin_list == NULL){
1056
break;
1057
}
1058
1059
continue;
1060
}
1061
1062
/* This process exited nicely, so print its buffer */
1063
1064
bool bret = print_out_password(proc->buffer,
1065
proc->buffer_length);
1066
if(not bret){
1067
perror("print_out_password");
1068
exitstatus = EXIT_FAILURE;
1069
}
1070
goto fallback;
1071
}
1072
1073
/* This process has not completed. Does it have any output? */
1074
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1075
/* This process had nothing to say at this time */
1076
proc = proc->next;
1077
continue;
1078
}
1079
/* Before reading, make the process' data buffer large enough */
1080
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1081
proc->buffer = realloc(proc->buffer, proc->buffer_size
1082
+ (size_t) BUFFER_SIZE);
1083
if(proc->buffer == NULL){
1084
perror("malloc");
1085
exitstatus = EXIT_FAILURE;
1086
goto fallback;
1087
}
1088
proc->buffer_size += BUFFER_SIZE;
1089
}
1090
/* Read from the process */
1091
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1092
proc->buffer
1093
+ proc->buffer_length,
1094
BUFFER_SIZE));
1095
if(sret < 0){
1096
/* Read error from this process; ignore the error */
1097
proc = proc->next;
1098
continue;
1099
}
1100
if(sret == 0){
1101
/* got EOF */
1102
proc->eof = true;
1103
} else {
1104
proc->buffer_length += (size_t) sret;
1105
}
1106
}
1107
}
1108
1109
1110
fallback:
1111
1112
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1113
/* Fallback if all plugins failed, none are found or an error
1114
occured */
1115
bool bret;
1116
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1117
char *passwordbuffer = getpass("Password: ");
1118
size_t len = strlen(passwordbuffer);
1119
/* Strip trailing newline */
1120
if(len > 0 and passwordbuffer[len-1] == '\n'){
1121
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1122
len--;
1123
}
1124
bret = print_out_password(passwordbuffer, len);
1125
if(not bret){
1126
perror("print_out_password");
1127
exitstatus = EXIT_FAILURE;
1128
}
1129
}
1130
1131
/* Restore old signal handler */
1132
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1133
if(ret == -1){
1134
perror("sigaction");
1135
exitstatus = EXIT_FAILURE;
1136
}
1137
1138
if(custom_argv != NULL){
1139
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1140
free(*arg);
1141
}
1142
free(custom_argv);
1143
}
1144
1145
if(dir != NULL){
1146
closedir(dir);
1147
}
1148
1149
/* Kill the processes */
1150
for(plugin *p = plugin_list; p != NULL; p = p->next){
1151
if(p->pid != 0){
1152
close(p->fd);
1153
ret = kill(p->pid, SIGTERM);
1154
if(ret == -1 and errno != ESRCH){
1155
/* Set-uid proccesses might not get closed */
1156
perror("kill");
1157
}
1158
}
1159
}
1160
1161
/* Wait for any remaining child processes to terminate */
1162
do {
1163
ret = wait(NULL);
1164
} while(ret >= 0);
1165
if(errno != ECHILD){
1166
perror("wait");
1167
}
1168
1169
free_plugin_list();
1170
1171
free(plugindir);
1172
free(argfile);
1173
1174
return exitstatus;
1175
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0