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- Committer: Björn Påhlsson
- Date: 2007-10-20 21:38:25 UTC
- Revision ID: belorn@tower-20071020213825-abf6f0d1c33ee961
First working version with: IPv6, GnuTLS, X.509 certificates, DN
retrieval.
retrieval.
- files added:
- bad-ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- plugins.d
- 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(), O_CLOEXEC */
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
29
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, fdopendir(), 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, fdopendir(),
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
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
72
EX_CONFIG, EX_UNAVAILABLE, EX_OK */
73
74
#define BUFFER_SIZE 256
75
76
#define PDIR "/lib/mandos/plugins.d"
77
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
78
79
const char *argp_program_version = "plugin-runner " VERSION;
80
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
81
82
typedef struct plugin{
83
char *name; /* can be NULL or any plugin name */
84
char **argv;
85
int argc;
86
char **environ;
87
int envc;
88
bool disabled;
89
90
/* Variables used for running processes*/
91
pid_t pid;
92
int fd;
93
char *buffer;
94
size_t buffer_size;
95
size_t buffer_length;
96
bool eof;
97
volatile sig_atomic_t completed;
98
int status;
99
struct plugin *next;
100
} plugin;
101
102
static plugin *plugin_list = NULL;
103
104
/* Gets an existing plugin based on name,
105
or if none is found, creates a new one */
106
static plugin *getplugin(char *name){
107
/* Check for existing plugin with that name */
108
for(plugin *p = plugin_list; p != NULL; p = p->next){
109
if((p->name == name)
110
or (p->name and name and (strcmp(p->name, name) == 0))){
111
return p;
112
}
113
}
114
/* Create a new plugin */
115
plugin *new_plugin = NULL;
116
do {
117
new_plugin = malloc(sizeof(plugin));
118
} while(new_plugin == NULL and errno == EINTR);
119
if(new_plugin == NULL){
120
return NULL;
121
}
122
char *copy_name = NULL;
123
if(name != NULL){
124
do {
125
copy_name = strdup(name);
126
} while(copy_name == NULL and errno == EINTR);
127
if(copy_name == NULL){
128
int e = errno;
129
free(new_plugin);
130
errno = e;
131
return NULL;
132
}
133
}
134
135
*new_plugin = (plugin){ .name = copy_name,
136
.argc = 1,
137
.disabled = false,
138
.next = plugin_list };
139
140
do {
141
new_plugin->argv = malloc(sizeof(char *) * 2);
142
} while(new_plugin->argv == NULL and errno == EINTR);
143
if(new_plugin->argv == NULL){
144
int e = errno;
145
free(copy_name);
146
free(new_plugin);
147
errno = e;
148
return NULL;
149
}
150
new_plugin->argv[0] = copy_name;
151
new_plugin->argv[1] = NULL;
152
153
do {
154
new_plugin->environ = malloc(sizeof(char *));
155
} while(new_plugin->environ == NULL and errno == EINTR);
156
if(new_plugin->environ == NULL){
157
int e = errno;
158
free(copy_name);
159
free(new_plugin->argv);
160
free(new_plugin);
161
errno = e;
162
return NULL;
163
}
164
new_plugin->environ[0] = NULL;
165
166
/* Append the new plugin to the list */
167
plugin_list = new_plugin;
168
return new_plugin;
169
}
170
171
/* Helper function for add_argument and add_environment */
172
static bool add_to_char_array(const char *new, char ***array,
173
int *len){
174
/* Resize the pointed-to array to hold one more pointer */
175
do {
176
*array = realloc(*array, sizeof(char *)
177
* (size_t) ((*len) + 2));
178
} while(*array == NULL and errno == EINTR);
179
/* Malloc check */
180
if(*array == NULL){
181
return false;
182
}
183
/* Make a copy of the new string */
184
char *copy;
185
do {
186
copy = strdup(new);
187
} while(copy == NULL and errno == EINTR);
188
if(copy == NULL){
189
return false;
190
}
191
/* Insert the copy */
192
(*array)[*len] = copy;
193
(*len)++;
194
/* Add a new terminating NULL pointer to the last element */
195
(*array)[*len] = NULL;
196
return true;
197
}
198
199
/* Add to a plugin's argument vector */
200
static bool add_argument(plugin *p, const char *arg){
201
if(p == NULL){
202
return false;
203
}
204
return add_to_char_array(arg, &(p->argv), &(p->argc));
205
}
206
207
/* Add to a plugin's environment */
208
static bool add_environment(plugin *p, const char *def, bool replace){
209
if(p == NULL){
210
return false;
211
}
212
/* namelen = length of name of environment variable */
213
size_t namelen = (size_t)(strchrnul(def, '=') - def);
214
/* Search for this environment variable */
215
for(char **e = p->environ; *e != NULL; e++){
216
if(strncmp(*e, def, namelen + 1) == 0){
217
/* It already exists */
218
if(replace){
219
char *new;
220
do {
221
new = realloc(*e, strlen(def) + 1);
222
} while(new == NULL and errno == EINTR);
223
if(new == NULL){
224
return false;
225
}
226
*e = new;
227
strcpy(*e, def);
228
}
229
return true;
230
}
231
}
232
return add_to_char_array(def, &(p->environ), &(p->envc));
233
}
234
235
/*
236
* Based on the example in the GNU LibC manual chapter 13.13 "File
237
* Descriptor Flags".
238
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
239
*/
240
static int set_cloexec_flag(int fd){
241
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
242
/* If reading the flags failed, return error indication now. */
243
if(ret < 0){
244
return ret;
245
}
246
/* Store modified flag word in the descriptor. */
247
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
248
ret | FD_CLOEXEC));
249
}
250
251
252
/* Mark processes as completed when they exit, and save their exit
253
status. */
254
static void handle_sigchld(__attribute__((unused)) int sig){
255
int old_errno = errno;
256
while(true){
257
plugin *proc = plugin_list;
258
int status;
259
pid_t pid = waitpid(-1, &status, WNOHANG);
260
if(pid == 0){
261
/* Only still running child processes */
262
break;
263
}
264
if(pid == -1){
265
if(errno == ECHILD){
266
/* No child processes */
267
break;
268
}
269
perror("waitpid");
270
}
271
272
/* A child exited, find it in process_list */
273
while(proc != NULL and proc->pid != pid){
274
proc = proc->next;
275
}
276
if(proc == NULL){
277
/* Process not found in process list */
278
continue;
279
}
280
proc->status = status;
281
proc->completed = 1;
282
}
283
errno = old_errno;
284
}
285
286
/* Prints out a password to stdout */
287
static bool print_out_password(const char *buffer, size_t length){
288
ssize_t ret;
289
for(size_t written = 0; written < length; written += (size_t)ret){
290
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
291
length - written));
292
if(ret < 0){
293
return false;
294
}
295
}
296
return true;
297
}
298
299
/* Removes and free a plugin from the plugin list */
300
static void free_plugin(plugin *plugin_node){
301
302
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
303
free(*arg);
304
}
305
free(plugin_node->argv);
306
for(char **env = plugin_node->environ; *env != NULL; env++){
307
free(*env);
308
}
309
free(plugin_node->environ);
310
free(plugin_node->buffer);
311
312
/* Removes the plugin from the singly-linked list */
313
if(plugin_node == plugin_list){
314
/* First one - simple */
315
plugin_list = plugin_list->next;
316
} else {
317
/* Second one or later */
318
for(plugin *p = plugin_list; p != NULL; p = p->next){
319
if(p->next == plugin_node){
320
p->next = plugin_node->next;
321
break;
322
}
323
}
324
}
325
326
free(plugin_node);
327
}
328
329
static void free_plugin_list(void){
330
while(plugin_list != NULL){
331
free_plugin(plugin_list);
332
}
333
}
334
335
int main(int argc, char *argv[]){
336
char *plugindir = NULL;
337
char *argfile = NULL;
338
FILE *conffp;
339
size_t d_name_len;
340
DIR *dir = NULL;
341
struct dirent *dirst;
342
struct stat st;
343
fd_set rfds_all;
344
int ret, maxfd = 0;
345
ssize_t sret;
346
uid_t uid = 65534;
347
gid_t gid = 65534;
348
bool debug = false;
349
int exitstatus = EXIT_SUCCESS;
350
struct sigaction old_sigchld_action;
351
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
352
.sa_flags = SA_NOCLDSTOP };
353
char **custom_argv = NULL;
354
int custom_argc = 0;
355
356
/* Establish a signal handler */
357
sigemptyset(&sigchld_action.sa_mask);
358
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
359
if(ret == -1){
360
perror("sigaddset");
361
exitstatus = EX_OSERR;
362
goto fallback;
363
}
364
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
365
if(ret == -1){
366
perror("sigaction");
367
exitstatus = EX_OSERR;
368
goto fallback;
369
}
370
371
/* The options we understand. */
372
struct argp_option options[] = {
373
{ .name = "global-options", .key = 'g',
374
.arg = "OPTION[,OPTION[,...]]",
375
.doc = "Options passed to all plugins" },
376
{ .name = "global-env", .key = 'G',
377
.arg = "VAR=value",
378
.doc = "Environment variable passed to all plugins" },
379
{ .name = "options-for", .key = 'o',
380
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
381
.doc = "Options passed only to specified plugin" },
382
{ .name = "env-for", .key = 'E',
383
.arg = "PLUGIN:ENV=value",
384
.doc = "Environment variable passed to specified plugin" },
385
{ .name = "disable", .key = 'd',
386
.arg = "PLUGIN",
387
.doc = "Disable a specific plugin", .group = 1 },
388
{ .name = "enable", .key = 'e',
389
.arg = "PLUGIN",
390
.doc = "Enable a specific plugin", .group = 1 },
391
{ .name = "plugin-dir", .key = 128,
392
.arg = "DIRECTORY",
393
.doc = "Specify a different plugin directory", .group = 2 },
394
{ .name = "config-file", .key = 129,
395
.arg = "FILE",
396
.doc = "Specify a different configuration file", .group = 2 },
397
{ .name = "userid", .key = 130,
398
.arg = "ID", .flags = 0,
399
.doc = "User ID the plugins will run as", .group = 3 },
400
{ .name = "groupid", .key = 131,
401
.arg = "ID", .flags = 0,
402
.doc = "Group ID the plugins will run as", .group = 3 },
403
{ .name = "debug", .key = 132,
404
.doc = "Debug mode", .group = 4 },
405
/*
406
* These reproduce what we would get without ARGP_NO_HELP
407
*/
408
{ .name = "help", .key = '?',
409
.doc = "Give this help list", .group = -1 },
410
{ .name = "usage", .key = -3,
411
.doc = "Give a short usage message", .group = -1 },
412
{ .name = "version", .key = 'V',
413
.doc = "Print program version", .group = -1 },
414
{ .name = NULL }
415
};
416
417
error_t parse_opt(int key, char *arg, struct argp_state *state){
418
errno = 0;
419
switch(key){
420
char *tmp;
421
intmax_t tmpmax;
422
case 'g': /* --global-options */
423
{
424
char *plugin_option;
425
while((plugin_option = strsep(&arg, ",")) != NULL){
426
if(not add_argument(getplugin(NULL), plugin_option)){
427
break;
428
}
429
}
430
}
431
break;
432
case 'G': /* --global-env */
433
add_environment(getplugin(NULL), arg, true);
434
break;
435
case 'o': /* --options-for */
436
{
437
char *option_list = strchr(arg, ':');
438
if(option_list == NULL){
439
argp_error(state, "No colon in \"%s\"", arg);
440
errno = EINVAL;
441
break;
442
}
443
*option_list = '\0';
444
option_list++;
445
if(arg[0] == '\0'){
446
argp_error(state, "Empty plugin name");
447
errno = EINVAL;
448
break;
449
}
450
char *option;
451
while((option = strsep(&option_list, ",")) != NULL){
452
if(not add_argument(getplugin(arg), option)){
453
break;
454
}
455
}
456
}
457
break;
458
case 'E': /* --env-for */
459
{
460
char *envdef = strchr(arg, ':');
461
if(envdef == NULL){
462
argp_error(state, "No colon in \"%s\"", arg);
463
errno = EINVAL;
464
break;
465
}
466
*envdef = '\0';
467
envdef++;
468
if(arg[0] == '\0'){
469
argp_error(state, "Empty plugin name");
470
errno = EINVAL;
471
break;
472
}
473
add_environment(getplugin(arg), envdef, true);
474
}
475
break;
476
case 'd': /* --disable */
477
{
478
plugin *p = getplugin(arg);
479
if(p != NULL){
480
p->disabled = true;
481
}
482
}
483
break;
484
case 'e': /* --enable */
485
{
486
plugin *p = getplugin(arg);
487
if(p != NULL){
488
p->disabled = false;
489
}
490
}
491
break;
492
case 128: /* --plugin-dir */
493
free(plugindir);
494
plugindir = strdup(arg);
495
break;
496
case 129: /* --config-file */
497
/* This is already done by parse_opt_config_file() */
498
break;
499
case 130: /* --userid */
500
tmpmax = strtoimax(arg, &tmp, 10);
501
if(errno != 0 or tmp == arg or *tmp != '\0'
502
or tmpmax != (uid_t)tmpmax){
503
argp_error(state, "Bad user ID number: \"%s\", using %"
504
PRIdMAX, arg, (intmax_t)uid);
505
break;
506
}
507
uid = (uid_t)tmpmax;
508
break;
509
case 131: /* --groupid */
510
tmpmax = strtoimax(arg, &tmp, 10);
511
if(errno != 0 or tmp == arg or *tmp != '\0'
512
or tmpmax != (gid_t)tmpmax){
513
argp_error(state, "Bad group ID number: \"%s\", using %"
514
PRIdMAX, arg, (intmax_t)gid);
515
break;
516
}
517
gid = (gid_t)tmpmax;
518
break;
519
case 132: /* --debug */
520
debug = true;
521
break;
522
/*
523
* These reproduce what we would get without ARGP_NO_HELP
524
*/
525
case '?': /* --help */
526
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
527
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
528
case -3: /* --usage */
529
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
530
argp_state_help(state, state->out_stream,
531
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
532
case 'V': /* --version */
533
fprintf(state->out_stream, "%s\n", argp_program_version);
534
exit(EXIT_SUCCESS);
535
break;
536
/*
537
* When adding more options before this line, remember to also add a
538
* "case" to the "parse_opt_config_file" function below.
539
*/
540
case ARGP_KEY_ARG:
541
/* Cryptsetup always passes an argument, which is an empty
542
string if "none" was specified in /etc/crypttab. So if
543
argument was empty, we ignore it silently. */
544
if(arg[0] == '\0'){
545
break;
546
}
547
default:
548
return ARGP_ERR_UNKNOWN;
549
}
550
return errno; /* Set to 0 at start */
551
}
552
553
/* This option parser is the same as parse_opt() above, except it
554
ignores everything but the --config-file option. */
555
error_t parse_opt_config_file(int key, char *arg,
556
__attribute__((unused))
557
struct argp_state *state){
558
errno = 0;
559
switch(key){
560
case 'g': /* --global-options */
561
case 'G': /* --global-env */
562
case 'o': /* --options-for */
563
case 'E': /* --env-for */
564
case 'd': /* --disable */
565
case 'e': /* --enable */
566
case 128: /* --plugin-dir */
567
break;
568
case 129: /* --config-file */
569
free(argfile);
570
argfile = strdup(arg);
571
break;
572
case 130: /* --userid */
573
case 131: /* --groupid */
574
case 132: /* --debug */
575
case '?': /* --help */
576
case -3: /* --usage */
577
case 'V': /* --version */
578
case ARGP_KEY_ARG:
579
break;
580
default:
581
return ARGP_ERR_UNKNOWN;
582
}
583
return errno;
584
}
585
586
struct argp argp = { .options = options,
587
.parser = parse_opt_config_file,
588
.args_doc = "",
589
.doc = "Mandos plugin runner -- Run plugins" };
590
591
/* Parse using parse_opt_config_file() in order to get the custom
592
config file location, if any. */
593
ret = argp_parse(&argp, argc, argv,
594
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
595
NULL, NULL);
596
switch(ret){
597
case 0:
598
break;
599
case ENOMEM:
600
default:
601
errno = ret;
602
perror("argp_parse");
603
exitstatus = EX_OSERR;
604
goto fallback;
605
case EINVAL:
606
exitstatus = EX_USAGE;
607
goto fallback;
608
}
609
610
/* Reset to the normal argument parser */
611
argp.parser = parse_opt;
612
613
/* Open the configfile if available */
614
if(argfile == NULL){
615
conffp = fopen(AFILE, "r");
616
} else {
617
conffp = fopen(argfile, "r");
618
}
619
if(conffp != NULL){
620
char *org_line = NULL;
621
char *p, *arg, *new_arg, *line;
622
size_t size = 0;
623
const char whitespace_delims[] = " \r\t\f\v\n";
624
const char comment_delim[] = "#";
625
626
custom_argc = 1;
627
custom_argv = malloc(sizeof(char*) * 2);
628
if(custom_argv == NULL){
629
perror("malloc");
630
exitstatus = EX_OSERR;
631
goto fallback;
632
}
633
custom_argv[0] = argv[0];
634
custom_argv[1] = NULL;
635
636
/* for each line in the config file, strip whitespace and ignore
637
commented text */
638
while(true){
639
sret = getline(&org_line, &size, conffp);
640
if(sret == -1){
641
break;
642
}
643
644
line = org_line;
645
arg = strsep(&line, comment_delim);
646
while((p = strsep(&arg, whitespace_delims)) != NULL){
647
if(p[0] == '\0'){
648
continue;
649
}
650
new_arg = strdup(p);
651
if(new_arg == NULL){
652
perror("strdup");
653
exitstatus = EX_OSERR;
654
free(org_line);
655
goto fallback;
656
}
657
658
custom_argc += 1;
659
custom_argv = realloc(custom_argv, sizeof(char *)
660
* ((unsigned int) custom_argc + 1));
661
if(custom_argv == NULL){
662
perror("realloc");
663
exitstatus = EX_OSERR;
664
free(org_line);
665
goto fallback;
666
}
667
custom_argv[custom_argc-1] = new_arg;
668
custom_argv[custom_argc] = NULL;
669
}
670
}
671
do {
672
ret = fclose(conffp);
673
} while(ret == EOF and errno == EINTR);
674
if(ret == EOF){
675
perror("fclose");
676
exitstatus = EX_IOERR;
677
goto fallback;
678
}
679
free(org_line);
680
} else {
681
/* Check for harmful errors and go to fallback. Other errors might
682
not affect opening plugins */
683
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
684
perror("fopen");
685
exitstatus = EX_IOERR;
686
goto fallback;
687
}
688
}
689
/* If there were any arguments from the configuration file, pass
690
them to parser as command line arguments */
691
if(custom_argv != NULL){
692
ret = argp_parse(&argp, custom_argc, custom_argv,
693
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
694
NULL, NULL);
695
switch(ret){
696
case 0:
697
break;
698
case ENOMEM:
699
default:
700
errno = ret;
701
perror("argp_parse");
702
exitstatus = EX_OSERR;
703
goto fallback;
704
case EINVAL:
705
exitstatus = EX_CONFIG;
706
goto fallback;
707
}
708
}
709
710
/* Parse actual command line arguments, to let them override the
711
config file */
712
ret = argp_parse(&argp, argc, argv,
713
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
714
NULL, NULL);
715
switch(ret){
716
case 0:
717
break;
718
case ENOMEM:
719
default:
720
errno = ret;
721
perror("argp_parse");
722
exitstatus = EX_OSERR;
723
goto fallback;
724
case EINVAL:
725
exitstatus = EX_USAGE;
726
goto fallback;
727
}
728
729
if(debug){
730
for(plugin *p = plugin_list; p != NULL; p=p->next){
731
fprintf(stderr, "Plugin: %s has %d arguments\n",
732
p->name ? p->name : "Global", p->argc - 1);
733
for(char **a = p->argv; *a != NULL; a++){
734
fprintf(stderr, "\tArg: %s\n", *a);
735
}
736
fprintf(stderr, "...and %d environment variables\n", p->envc);
737
for(char **a = p->environ; *a != NULL; a++){
738
fprintf(stderr, "\t%s\n", *a);
739
}
740
}
741
}
742
743
/* Strip permissions down to nobody */
744
setgid(gid);
745
if(ret == -1){
746
perror("setgid");
747
}
748
ret = setuid(uid);
749
if(ret == -1){
750
perror("setuid");
751
}
752
753
/* Open plugin directory with close_on_exec flag */
754
{
755
int dir_fd = -1;
756
if(plugindir == NULL){
757
dir_fd = open(PDIR, O_RDONLY |
758
#ifdef O_CLOEXEC
759
O_CLOEXEC
760
#else /* not O_CLOEXEC */
761
0
762
#endif /* not O_CLOEXEC */
763
);
764
} else {
765
dir_fd = open(plugindir, O_RDONLY |
766
#ifdef O_CLOEXEC
767
O_CLOEXEC
768
#else /* not O_CLOEXEC */
769
0
770
#endif /* not O_CLOEXEC */
771
);
772
}
773
if(dir_fd == -1){
774
perror("Could not open plugin dir");
775
exitstatus = EX_UNAVAILABLE;
776
goto fallback;
777
}
778
779
#ifndef O_CLOEXEC
780
/* Set the FD_CLOEXEC flag on the directory */
781
ret = set_cloexec_flag(dir_fd);
782
if(ret < 0){
783
perror("set_cloexec_flag");
784
TEMP_FAILURE_RETRY(close(dir_fd));
785
exitstatus = EX_OSERR;
786
goto fallback;
787
}
788
#endif /* O_CLOEXEC */
789
790
dir = fdopendir(dir_fd);
791
if(dir == NULL){
792
perror("Could not open plugin dir");
793
TEMP_FAILURE_RETRY(close(dir_fd));
794
exitstatus = EX_OSERR;
795
goto fallback;
796
}
797
}
798
799
FD_ZERO(&rfds_all);
800
801
/* Read and execute any executable in the plugin directory*/
802
while(true){
803
do {
804
dirst = readdir(dir);
805
} while(dirst == NULL and errno == EINTR);
806
807
/* All directory entries have been processed */
808
if(dirst == NULL){
809
if(errno == EBADF){
810
perror("readdir");
811
exitstatus = EX_IOERR;
812
goto fallback;
813
}
814
break;
815
}
816
817
d_name_len = strlen(dirst->d_name);
818
819
/* Ignore dotfiles, backup files and other junk */
820
{
821
bool bad_name = false;
822
823
const char const *bad_prefixes[] = { ".", "#", NULL };
824
825
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
826
".dpkg-old",
827
".dpkg-bak",
828
".dpkg-divert", NULL };
829
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
830
size_t pre_len = strlen(*pre);
831
if((d_name_len >= pre_len)
832
and strncmp((dirst->d_name), *pre, pre_len) == 0){
833
if(debug){
834
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
835
" with bad prefix %s\n", dirst->d_name, *pre);
836
}
837
bad_name = true;
838
break;
839
}
840
}
841
if(bad_name){
842
continue;
843
}
844
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
845
size_t suf_len = strlen(*suf);
846
if((d_name_len >= suf_len)
847
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
848
== 0)){
849
if(debug){
850
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
851
" with bad suffix %s\n", dirst->d_name, *suf);
852
}
853
bad_name = true;
854
break;
855
}
856
}
857
858
if(bad_name){
859
continue;
860
}
861
}
862
863
char *filename;
864
if(plugindir == NULL){
865
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
866
dirst->d_name));
867
} else {
868
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
869
plugindir,
870
dirst->d_name));
871
}
872
if(ret < 0){
873
perror("asprintf");
874
continue;
875
}
876
877
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
878
if(ret == -1){
879
perror("stat");
880
free(filename);
881
continue;
882
}
883
884
/* Ignore non-executable files */
885
if(not S_ISREG(st.st_mode)
886
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
887
if(debug){
888
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
889
" with bad type or mode\n", filename);
890
}
891
free(filename);
892
continue;
893
}
894
895
plugin *p = getplugin(dirst->d_name);
896
if(p == NULL){
897
perror("getplugin");
898
free(filename);
899
continue;
900
}
901
if(p->disabled){
902
if(debug){
903
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
904
dirst->d_name);
905
}
906
free(filename);
907
continue;
908
}
909
{
910
/* Add global arguments to argument list for this plugin */
911
plugin *g = getplugin(NULL);
912
if(g != NULL){
913
for(char **a = g->argv + 1; *a != NULL; a++){
914
if(not add_argument(p, *a)){
915
perror("add_argument");
916
}
917
}
918
/* Add global environment variables */
919
for(char **e = g->environ; *e != NULL; e++){
920
if(not add_environment(p, *e, false)){
921
perror("add_environment");
922
}
923
}
924
}
925
}
926
/* If this plugin has any environment variables, we will call
927
using execve and need to duplicate the environment from this
928
process, too. */
929
if(p->environ[0] != NULL){
930
for(char **e = environ; *e != NULL; e++){
931
if(not add_environment(p, *e, false)){
932
perror("add_environment");
933
}
934
}
935
}
936
937
int pipefd[2];
938
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
939
if(ret == -1){
940
perror("pipe");
941
exitstatus = EX_OSERR;
942
goto fallback;
943
}
944
/* Ask OS to automatic close the pipe on exec */
945
ret = set_cloexec_flag(pipefd[0]);
946
if(ret < 0){
947
perror("set_cloexec_flag");
948
exitstatus = EX_OSERR;
949
goto fallback;
950
}
951
ret = set_cloexec_flag(pipefd[1]);
952
if(ret < 0){
953
perror("set_cloexec_flag");
954
exitstatus = EX_OSERR;
955
goto fallback;
956
}
957
/* Block SIGCHLD until process is safely in process list */
958
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
959
&sigchld_action.sa_mask,
960
NULL));
961
if(ret < 0){
962
perror("sigprocmask");
963
exitstatus = EX_OSERR;
964
goto fallback;
965
}
966
/* Starting a new process to be watched */
967
pid_t pid;
968
do {
969
pid = fork();
970
} while(pid == -1 and errno == EINTR);
971
if(pid == -1){
972
perror("fork");
973
exitstatus = EX_OSERR;
974
goto fallback;
975
}
976
if(pid == 0){
977
/* this is the child process */
978
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
979
if(ret < 0){
980
perror("sigaction");
981
_exit(EX_OSERR);
982
}
983
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
984
if(ret < 0){
985
perror("sigprocmask");
986
_exit(EX_OSERR);
987
}
988
989
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
990
if(ret == -1){
991
perror("dup2");
992
_exit(EX_OSERR);
993
}
994
995
if(dirfd(dir) < 0){
996
/* If dir has no file descriptor, we could not set FD_CLOEXEC
997
above and must now close it manually here. */
998
closedir(dir);
999
}
1000
if(p->environ[0] == NULL){
1001
if(execv(filename, p->argv) < 0){
1002
perror("execv");
1003
_exit(EX_OSERR);
1004
}
1005
} else {
1006
if(execve(filename, p->argv, p->environ) < 0){
1007
perror("execve");
1008
_exit(EX_OSERR);
1009
}
1010
}
1011
/* no return */
1012
}
1013
/* Parent process */
1014
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1015
pipe */
1016
free(filename);
1017
plugin *new_plugin = getplugin(dirst->d_name);
1018
if(new_plugin == NULL){
1019
perror("getplugin");
1020
ret = (int)(TEMP_FAILURE_RETRY
1021
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1022
NULL)));
1023
if(ret < 0){
1024
perror("sigprocmask");
1025
}
1026
exitstatus = EX_OSERR;
1027
goto fallback;
1028
}
1029
1030
new_plugin->pid = pid;
1031
new_plugin->fd = pipefd[0];
1032
1033
/* Unblock SIGCHLD so signal handler can be run if this process
1034
has already completed */
1035
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1036
&sigchld_action.sa_mask,
1037
NULL));
1038
if(ret < 0){
1039
perror("sigprocmask");
1040
exitstatus = EX_OSERR;
1041
goto fallback;
1042
}
1043
1044
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1045
-Wconversion */
1046
1047
if(maxfd < new_plugin->fd){
1048
maxfd = new_plugin->fd;
1049
}
1050
}
1051
1052
TEMP_FAILURE_RETRY(closedir(dir));
1053
dir = NULL;
1054
free_plugin(getplugin(NULL));
1055
1056
for(plugin *p = plugin_list; p != NULL; p = p->next){
1057
if(p->pid != 0){
1058
break;
1059
}
1060
if(p->next == NULL){
1061
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1062
" directory?\n");
1063
free_plugin_list();
1064
}
1065
}
1066
1067
/* Main loop while running plugins exist */
1068
while(plugin_list){
1069
fd_set rfds = rfds_all;
1070
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1071
if(select_ret == -1 and errno != EINTR){
1072
perror("select");
1073
exitstatus = EX_OSERR;
1074
goto fallback;
1075
}
1076
/* OK, now either a process completed, or something can be read
1077
from one of them */
1078
for(plugin *proc = plugin_list; proc != NULL;){
1079
/* Is this process completely done? */
1080
if(proc->completed and proc->eof){
1081
/* Only accept the plugin output if it exited cleanly */
1082
if(not WIFEXITED(proc->status)
1083
or WEXITSTATUS(proc->status) != 0){
1084
/* Bad exit by plugin */
1085
1086
if(debug){
1087
if(WIFEXITED(proc->status)){
1088
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1089
" status %d\n", proc->name,
1090
(intmax_t) (proc->pid),
1091
WEXITSTATUS(proc->status));
1092
} else if(WIFSIGNALED(proc->status)){
1093
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1094
" signal %d: %s\n", proc->name,
1095
(intmax_t) (proc->pid),
1096
WTERMSIG(proc->status),
1097
strsignal(WTERMSIG(proc->status)));
1098
} else if(WCOREDUMP(proc->status)){
1099
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1100
" core\n", proc->name, (intmax_t) (proc->pid));
1101
}
1102
}
1103
1104
/* Remove the plugin */
1105
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1106
-Wconversion */
1107
1108
/* Block signal while modifying process_list */
1109
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1110
(SIG_BLOCK,
1111
&sigchld_action.sa_mask,
1112
NULL));
1113
if(ret < 0){
1114
perror("sigprocmask");
1115
exitstatus = EX_OSERR;
1116
goto fallback;
1117
}
1118
1119
plugin *next_plugin = proc->next;
1120
free_plugin(proc);
1121
proc = next_plugin;
1122
1123
/* We are done modifying process list, so unblock signal */
1124
ret = (int)(TEMP_FAILURE_RETRY
1125
(sigprocmask(SIG_UNBLOCK,
1126
&sigchld_action.sa_mask, NULL)));
1127
if(ret < 0){
1128
perror("sigprocmask");
1129
exitstatus = EX_OSERR;
1130
goto fallback;
1131
}
1132
1133
if(plugin_list == NULL){
1134
break;
1135
}
1136
1137
continue;
1138
}
1139
1140
/* This process exited nicely, so print its buffer */
1141
1142
bool bret = print_out_password(proc->buffer,
1143
proc->buffer_length);
1144
if(not bret){
1145
perror("print_out_password");
1146
exitstatus = EX_IOERR;
1147
}
1148
goto fallback;
1149
}
1150
1151
/* This process has not completed. Does it have any output? */
1152
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1153
warning from
1154
-Wconversion */
1155
/* This process had nothing to say at this time */
1156
proc = proc->next;
1157
continue;
1158
}
1159
/* Before reading, make the process' data buffer large enough */
1160
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1161
proc->buffer = realloc(proc->buffer, proc->buffer_size
1162
+ (size_t) BUFFER_SIZE);
1163
if(proc->buffer == NULL){
1164
perror("malloc");
1165
exitstatus = EX_OSERR;
1166
goto fallback;
1167
}
1168
proc->buffer_size += BUFFER_SIZE;
1169
}
1170
/* Read from the process */
1171
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1172
proc->buffer
1173
+ proc->buffer_length,
1174
BUFFER_SIZE));
1175
if(sret < 0){
1176
/* Read error from this process; ignore the error */
1177
proc = proc->next;
1178
continue;
1179
}
1180
if(sret == 0){
1181
/* got EOF */
1182
proc->eof = true;
1183
} else {
1184
proc->buffer_length += (size_t) sret;
1185
}
1186
}
1187
}
1188
1189
1190
fallback:
1191
1192
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1193
and exitstatus != EX_OK)){
1194
/* Fallback if all plugins failed, none are found or an error
1195
occured */
1196
bool bret;
1197
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1198
char *passwordbuffer = getpass("Password: ");
1199
size_t len = strlen(passwordbuffer);
1200
/* Strip trailing newline */
1201
if(len > 0 and passwordbuffer[len-1] == '\n'){
1202
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1203
len--;
1204
}
1205
bret = print_out_password(passwordbuffer, len);
1206
if(not bret){
1207
perror("print_out_password");
1208
exitstatus = EX_IOERR;
1209
}
1210
}
1211
1212
/* Restore old signal handler */
1213
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1214
if(ret == -1){
1215
perror("sigaction");
1216
exitstatus = EX_OSERR;
1217
}
1218
1219
if(custom_argv != NULL){
1220
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1221
free(*arg);
1222
}
1223
free(custom_argv);
1224
}
1225
1226
if(dir != NULL){
1227
closedir(dir);
1228
}
1229
1230
/* Kill the processes */
1231
for(plugin *p = plugin_list; p != NULL; p = p->next){
1232
if(p->pid != 0){
1233
close(p->fd);
1234
ret = kill(p->pid, SIGTERM);
1235
if(ret == -1 and errno != ESRCH){
1236
/* Set-uid proccesses might not get closed */
1237
perror("kill");
1238
}
1239
}
1240
}
1241
1242
/* Wait for any remaining child processes to terminate */
1243
do {
1244
ret = wait(NULL);
1245
} while(ret >= 0);
1246
if(errno != ECHILD){
1247
perror("wait");
1248
}
1249
1250
free_plugin_list();
1251
1252
free(plugindir);
1253
free(argfile);
1254
1255
return exitstatus;
1256
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0