To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/release
« back to all changes in this revision
Viewing changes to plugin-runner.c
- browse files at revision 265
- compare with another revision
- download diff
- download tarball
- view history from revision 265
- Committer: Teddy Hogeborn
- Date: 2009-09-17 13:18:08 UTC
- Revision ID: teddy@fukt.bsnet.se-20090917131808-wdn07kozk4wgnt4m
Tags: version-1.0.12-1
* Makefile (version): Changed to "1.0.12".
* NEWS (Version 1.0.12): New entry.
* debian/changelog (1.0.12-1): - '' -
* NEWS (Version 1.0.12): New entry.
* debian/changelog (1.0.12-1): - '' -
- files added:
- .bzr-builddeb
- debian
- debian/po
- plugins.d
- files removed:
- 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 = (int)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 (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
240
ret | FD_CLOEXEC));
241
}
242
243
244
/* Mark processes as completed when they exit, and save their exit
245
status. */
246
static void handle_sigchld(__attribute__((unused)) int sig){
247
int old_errno = errno;
248
while(true){
249
plugin *proc = plugin_list;
250
int status;
251
pid_t pid = waitpid(-1, &status, WNOHANG);
252
if(pid == 0){
253
/* Only still running child processes */
254
break;
255
}
256
if(pid == -1){
257
if(errno == ECHILD){
258
/* No child processes */
259
break;
260
}
261
perror("waitpid");
262
}
263
264
/* A child exited, find it in process_list */
265
while(proc != NULL and proc->pid != pid){
266
proc = proc->next;
267
}
268
if(proc == NULL){
269
/* Process not found in process list */
270
continue;
271
}
272
proc->status = status;
273
proc->completed = 1;
274
}
275
errno = old_errno;
276
}
277
278
/* Prints out a password to stdout */
279
static bool print_out_password(const char *buffer, size_t length){
280
ssize_t ret;
281
for(size_t written = 0; written < length; written += (size_t)ret){
282
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
283
length - written));
284
if(ret < 0){
285
return false;
286
}
287
}
288
return true;
289
}
290
291
/* Removes and free a plugin from the plugin list */
292
static void free_plugin(plugin *plugin_node){
293
294
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
295
free(*arg);
296
}
297
free(plugin_node->argv);
298
for(char **env = plugin_node->environ; *env != NULL; env++){
299
free(*env);
300
}
301
free(plugin_node->environ);
302
free(plugin_node->buffer);
303
304
/* Removes the plugin from the singly-linked list */
305
if(plugin_node == plugin_list){
306
/* First one - simple */
307
plugin_list = plugin_list->next;
308
} else {
309
/* Second one or later */
310
for(plugin *p = plugin_list; p != NULL; p = p->next){
311
if(p->next == plugin_node){
312
p->next = plugin_node->next;
313
break;
314
}
315
}
316
}
317
318
free(plugin_node);
319
}
320
321
static void free_plugin_list(void){
322
while(plugin_list != NULL){
323
free_plugin(plugin_list);
324
}
325
}
326
327
int main(int argc, char *argv[]){
328
char *plugindir = NULL;
329
char *argfile = NULL;
330
FILE *conffp;
331
size_t d_name_len;
332
DIR *dir = NULL;
333
struct dirent *dirst;
334
struct stat st;
335
fd_set rfds_all;
336
int ret, maxfd = 0;
337
ssize_t sret;
338
uid_t uid = 65534;
339
gid_t gid = 65534;
340
bool debug = false;
341
int exitstatus = EXIT_SUCCESS;
342
struct sigaction old_sigchld_action;
343
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
344
.sa_flags = SA_NOCLDSTOP };
345
char **custom_argv = NULL;
346
int custom_argc = 0;
347
348
/* Establish a signal handler */
349
sigemptyset(&sigchld_action.sa_mask);
350
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
351
if(ret == -1){
352
perror("sigaddset");
353
exitstatus = EXIT_FAILURE;
354
goto fallback;
355
}
356
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
357
if(ret == -1){
358
perror("sigaction");
359
exitstatus = EXIT_FAILURE;
360
goto fallback;
361
}
362
363
/* The options we understand. */
364
struct argp_option options[] = {
365
{ .name = "global-options", .key = 'g',
366
.arg = "OPTION[,OPTION[,...]]",
367
.doc = "Options passed to all plugins" },
368
{ .name = "global-env", .key = 'G',
369
.arg = "VAR=value",
370
.doc = "Environment variable passed to all plugins" },
371
{ .name = "options-for", .key = 'o',
372
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
373
.doc = "Options passed only to specified plugin" },
374
{ .name = "env-for", .key = 'E',
375
.arg = "PLUGIN:ENV=value",
376
.doc = "Environment variable passed to specified plugin" },
377
{ .name = "disable", .key = 'd',
378
.arg = "PLUGIN",
379
.doc = "Disable a specific plugin", .group = 1 },
380
{ .name = "enable", .key = 'e',
381
.arg = "PLUGIN",
382
.doc = "Enable a specific plugin", .group = 1 },
383
{ .name = "plugin-dir", .key = 128,
384
.arg = "DIRECTORY",
385
.doc = "Specify a different plugin directory", .group = 2 },
386
{ .name = "config-file", .key = 129,
387
.arg = "FILE",
388
.doc = "Specify a different configuration file", .group = 2 },
389
{ .name = "userid", .key = 130,
390
.arg = "ID", .flags = 0,
391
.doc = "User ID the plugins will run as", .group = 3 },
392
{ .name = "groupid", .key = 131,
393
.arg = "ID", .flags = 0,
394
.doc = "Group ID the plugins will run as", .group = 3 },
395
{ .name = "debug", .key = 132,
396
.doc = "Debug mode", .group = 4 },
397
{ .name = NULL }
398
};
399
400
error_t parse_opt(int key, char *arg, __attribute__((unused))
401
struct argp_state *state){
402
switch(key){
403
char *tmp;
404
intmax_t tmpmax;
405
case 'g': /* --global-options */
406
if(arg != NULL){
407
char *plugin_option;
408
while((plugin_option = strsep(&arg, ",")) != NULL){
409
if(plugin_option[0] == '\0'){
410
continue;
411
}
412
if(not add_argument(getplugin(NULL), plugin_option)){
413
perror("add_argument");
414
return ARGP_ERR_UNKNOWN;
415
}
416
}
417
}
418
break;
419
case 'G': /* --global-env */
420
if(arg == NULL){
421
break;
422
}
423
if(not add_environment(getplugin(NULL), arg, true)){
424
perror("add_environment");
425
}
426
break;
427
case 'o': /* --options-for */
428
if(arg != NULL){
429
char *plugin_name = strsep(&arg, ":");
430
if(plugin_name[0] == '\0'){
431
break;
432
}
433
char *plugin_option;
434
while((plugin_option = strsep(&arg, ",")) != NULL){
435
if(not add_argument(getplugin(plugin_name), plugin_option)){
436
perror("add_argument");
437
return ARGP_ERR_UNKNOWN;
438
}
439
}
440
}
441
break;
442
case 'E': /* --env-for */
443
if(arg == NULL){
444
break;
445
}
446
{
447
char *envdef = strchr(arg, ':');
448
if(envdef == NULL){
449
break;
450
}
451
*envdef = '\0';
452
if(not add_environment(getplugin(arg), envdef+1, true)){
453
perror("add_environment");
454
}
455
}
456
break;
457
case 'd': /* --disable */
458
if(arg != NULL){
459
plugin *p = getplugin(arg);
460
if(p == NULL){
461
return ARGP_ERR_UNKNOWN;
462
}
463
p->disabled = true;
464
}
465
break;
466
case 'e': /* --enable */
467
if(arg != NULL){
468
plugin *p = getplugin(arg);
469
if(p == NULL){
470
return ARGP_ERR_UNKNOWN;
471
}
472
p->disabled = false;
473
}
474
break;
475
case 128: /* --plugin-dir */
476
free(plugindir);
477
plugindir = strdup(arg);
478
if(plugindir == NULL){
479
perror("strdup");
480
}
481
break;
482
case 129: /* --config-file */
483
/* This is already done by parse_opt_config_file() */
484
break;
485
case 130: /* --userid */
486
errno = 0;
487
tmpmax = strtoimax(arg, &tmp, 10);
488
if(errno != 0 or tmp == arg or *tmp != '\0'
489
or tmpmax != (uid_t)tmpmax){
490
fprintf(stderr, "Bad user ID number: \"%s\", using %"
491
PRIdMAX "\n", arg, (intmax_t)uid);
492
} else {
493
uid = (uid_t)tmpmax;
494
}
495
break;
496
case 131: /* --groupid */
497
errno = 0;
498
tmpmax = strtoimax(arg, &tmp, 10);
499
if(errno != 0 or tmp == arg or *tmp != '\0'
500
or tmpmax != (gid_t)tmpmax){
501
fprintf(stderr, "Bad group ID number: \"%s\", using %"
502
PRIdMAX "\n", arg, (intmax_t)gid);
503
} else {
504
gid = (gid_t)tmpmax;
505
}
506
break;
507
case 132: /* --debug */
508
debug = true;
509
break;
510
/*
511
* When adding more options before this line, remember to also add a
512
* "case" to the "parse_opt_config_file" function below.
513
*/
514
case ARGP_KEY_ARG:
515
/* Cryptsetup always passes an argument, which is an empty
516
string if "none" was specified in /etc/crypttab. So if
517
argument was empty, we ignore it silently. */
518
if(arg[0] != '\0'){
519
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
520
}
521
break;
522
case ARGP_KEY_END:
523
break;
524
default:
525
return ARGP_ERR_UNKNOWN;
526
}
527
return 0;
528
}
529
530
/* This option parser is the same as parse_opt() above, except it
531
ignores everything but the --config-file option. */
532
error_t parse_opt_config_file(int key, char *arg,
533
__attribute__((unused))
534
struct argp_state *state){
535
switch(key){
536
case 'g': /* --global-options */
537
case 'G': /* --global-env */
538
case 'o': /* --options-for */
539
case 'E': /* --env-for */
540
case 'd': /* --disable */
541
case 'e': /* --enable */
542
case 128: /* --plugin-dir */
543
break;
544
case 129: /* --config-file */
545
free(argfile);
546
argfile = strdup(arg);
547
if(argfile == NULL){
548
perror("strdup");
549
}
550
break;
551
case 130: /* --userid */
552
case 131: /* --groupid */
553
case 132: /* --debug */
554
case ARGP_KEY_ARG:
555
case ARGP_KEY_END:
556
break;
557
default:
558
return ARGP_ERR_UNKNOWN;
559
}
560
return 0;
561
}
562
563
struct argp argp = { .options = options,
564
.parser = parse_opt_config_file,
565
.args_doc = "",
566
.doc = "Mandos plugin runner -- Run plugins" };
567
568
/* Parse using parse_opt_config_file() in order to get the custom
569
config file location, if any. */
570
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
571
if(ret == ARGP_ERR_UNKNOWN){
572
fprintf(stderr, "Unknown error while parsing arguments\n");
573
exitstatus = EXIT_FAILURE;
574
goto fallback;
575
}
576
577
/* Reset to the normal argument parser */
578
argp.parser = parse_opt;
579
580
/* Open the configfile if available */
581
if(argfile == NULL){
582
conffp = fopen(AFILE, "r");
583
} else {
584
conffp = fopen(argfile, "r");
585
}
586
if(conffp != NULL){
587
char *org_line = NULL;
588
char *p, *arg, *new_arg, *line;
589
size_t size = 0;
590
const char whitespace_delims[] = " \r\t\f\v\n";
591
const char comment_delim[] = "#";
592
593
custom_argc = 1;
594
custom_argv = malloc(sizeof(char*) * 2);
595
if(custom_argv == NULL){
596
perror("malloc");
597
exitstatus = EXIT_FAILURE;
598
goto fallback;
599
}
600
custom_argv[0] = argv[0];
601
custom_argv[1] = NULL;
602
603
/* for each line in the config file, strip whitespace and ignore
604
commented text */
605
while(true){
606
sret = getline(&org_line, &size, conffp);
607
if(sret == -1){
608
break;
609
}
610
611
line = org_line;
612
arg = strsep(&line, comment_delim);
613
while((p = strsep(&arg, whitespace_delims)) != NULL){
614
if(p[0] == '\0'){
615
continue;
616
}
617
new_arg = strdup(p);
618
if(new_arg == NULL){
619
perror("strdup");
620
exitstatus = EXIT_FAILURE;
621
free(org_line);
622
goto fallback;
623
}
624
625
custom_argc += 1;
626
custom_argv = realloc(custom_argv, sizeof(char *)
627
* ((unsigned int) custom_argc + 1));
628
if(custom_argv == NULL){
629
perror("realloc");
630
exitstatus = EXIT_FAILURE;
631
free(org_line);
632
goto fallback;
633
}
634
custom_argv[custom_argc-1] = new_arg;
635
custom_argv[custom_argc] = NULL;
636
}
637
}
638
do {
639
ret = fclose(conffp);
640
} while(ret == EOF and errno == EINTR);
641
if(ret == EOF){
642
perror("fclose");
643
exitstatus = EXIT_FAILURE;
644
goto fallback;
645
}
646
free(org_line);
647
} else {
648
/* Check for harmful errors and go to fallback. Other errors might
649
not affect opening plugins */
650
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
651
perror("fopen");
652
exitstatus = EXIT_FAILURE;
653
goto fallback;
654
}
655
}
656
/* If there was any arguments from configuration file,
657
pass them to parser as command arguments */
658
if(custom_argv != NULL){
659
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
660
0, NULL);
661
if(ret == ARGP_ERR_UNKNOWN){
662
fprintf(stderr, "Unknown error while parsing arguments\n");
663
exitstatus = EXIT_FAILURE;
664
goto fallback;
665
}
666
}
667
668
/* Parse actual command line arguments, to let them override the
669
config file */
670
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
671
if(ret == ARGP_ERR_UNKNOWN){
672
fprintf(stderr, "Unknown error while parsing arguments\n");
673
exitstatus = EXIT_FAILURE;
674
goto fallback;
675
}
676
677
if(debug){
678
for(plugin *p = plugin_list; p != NULL; p=p->next){
679
fprintf(stderr, "Plugin: %s has %d arguments\n",
680
p->name ? p->name : "Global", p->argc - 1);
681
for(char **a = p->argv; *a != NULL; a++){
682
fprintf(stderr, "\tArg: %s\n", *a);
683
}
684
fprintf(stderr, "...and %d environment variables\n", p->envc);
685
for(char **a = p->environ; *a != NULL; a++){
686
fprintf(stderr, "\t%s\n", *a);
687
}
688
}
689
}
690
691
/* Strip permissions down to nobody */
692
setgid(gid);
693
if(ret == -1){
694
perror("setgid");
695
}
696
ret = setuid(uid);
697
if(ret == -1){
698
perror("setuid");
699
}
700
701
if(plugindir == NULL){
702
dir = opendir(PDIR);
703
} else {
704
dir = opendir(plugindir);
705
}
706
707
if(dir == NULL){
708
perror("Could not open plugin dir");
709
exitstatus = EXIT_FAILURE;
710
goto fallback;
711
}
712
713
/* Set the FD_CLOEXEC flag on the directory, if possible */
714
{
715
int dir_fd = dirfd(dir);
716
if(dir_fd >= 0){
717
ret = set_cloexec_flag(dir_fd);
718
if(ret < 0){
719
perror("set_cloexec_flag");
720
exitstatus = EXIT_FAILURE;
721
goto fallback;
722
}
723
}
724
}
725
726
FD_ZERO(&rfds_all);
727
728
/* Read and execute any executable in the plugin directory*/
729
while(true){
730
do {
731
dirst = readdir(dir);
732
} while(dirst == NULL and errno == EINTR);
733
734
/* All directory entries have been processed */
735
if(dirst == NULL){
736
if(errno == EBADF){
737
perror("readdir");
738
exitstatus = EXIT_FAILURE;
739
goto fallback;
740
}
741
break;
742
}
743
744
d_name_len = strlen(dirst->d_name);
745
746
/* Ignore dotfiles, backup files and other junk */
747
{
748
bool bad_name = false;
749
750
const char const *bad_prefixes[] = { ".", "#", NULL };
751
752
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
753
".dpkg-old",
754
".dpkg-bak",
755
".dpkg-divert", NULL };
756
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
757
size_t pre_len = strlen(*pre);
758
if((d_name_len >= pre_len)
759
and strncmp((dirst->d_name), *pre, pre_len) == 0){
760
if(debug){
761
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
762
" with bad prefix %s\n", dirst->d_name, *pre);
763
}
764
bad_name = true;
765
break;
766
}
767
}
768
if(bad_name){
769
continue;
770
}
771
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
772
size_t suf_len = strlen(*suf);
773
if((d_name_len >= suf_len)
774
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
775
== 0)){
776
if(debug){
777
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
778
" with bad suffix %s\n", dirst->d_name, *suf);
779
}
780
bad_name = true;
781
break;
782
}
783
}
784
785
if(bad_name){
786
continue;
787
}
788
}
789
790
char *filename;
791
if(plugindir == NULL){
792
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
793
dirst->d_name));
794
} else {
795
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
796
plugindir,
797
dirst->d_name));
798
}
799
if(ret < 0){
800
perror("asprintf");
801
continue;
802
}
803
804
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
805
if(ret == -1){
806
perror("stat");
807
free(filename);
808
continue;
809
}
810
811
/* Ignore non-executable files */
812
if(not S_ISREG(st.st_mode)
813
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
814
if(debug){
815
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
816
" with bad type or mode\n", filename);
817
}
818
free(filename);
819
continue;
820
}
821
822
plugin *p = getplugin(dirst->d_name);
823
if(p == NULL){
824
perror("getplugin");
825
free(filename);
826
continue;
827
}
828
if(p->disabled){
829
if(debug){
830
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
831
dirst->d_name);
832
}
833
free(filename);
834
continue;
835
}
836
{
837
/* Add global arguments to argument list for this plugin */
838
plugin *g = getplugin(NULL);
839
if(g != NULL){
840
for(char **a = g->argv + 1; *a != NULL; a++){
841
if(not add_argument(p, *a)){
842
perror("add_argument");
843
}
844
}
845
/* Add global environment variables */
846
for(char **e = g->environ; *e != NULL; e++){
847
if(not add_environment(p, *e, false)){
848
perror("add_environment");
849
}
850
}
851
}
852
}
853
/* If this plugin has any environment variables, we will call
854
using execve and need to duplicate the environment from this
855
process, too. */
856
if(p->environ[0] != NULL){
857
for(char **e = environ; *e != NULL; e++){
858
if(not add_environment(p, *e, false)){
859
perror("add_environment");
860
}
861
}
862
}
863
864
int pipefd[2];
865
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
866
if(ret == -1){
867
perror("pipe");
868
exitstatus = EXIT_FAILURE;
869
goto fallback;
870
}
871
/* Ask OS to automatic close the pipe on exec */
872
ret = set_cloexec_flag(pipefd[0]);
873
if(ret < 0){
874
perror("set_cloexec_flag");
875
exitstatus = EXIT_FAILURE;
876
goto fallback;
877
}
878
ret = set_cloexec_flag(pipefd[1]);
879
if(ret < 0){
880
perror("set_cloexec_flag");
881
exitstatus = EXIT_FAILURE;
882
goto fallback;
883
}
884
/* Block SIGCHLD until process is safely in process list */
885
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
886
&sigchld_action.sa_mask,
887
NULL));
888
if(ret < 0){
889
perror("sigprocmask");
890
exitstatus = EXIT_FAILURE;
891
goto fallback;
892
}
893
/* Starting a new process to be watched */
894
pid_t pid;
895
do {
896
pid = fork();
897
} while(pid == -1 and errno == EINTR);
898
if(pid == -1){
899
perror("fork");
900
exitstatus = EXIT_FAILURE;
901
goto fallback;
902
}
903
if(pid == 0){
904
/* this is the child process */
905
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
906
if(ret < 0){
907
perror("sigaction");
908
_exit(EXIT_FAILURE);
909
}
910
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
911
if(ret < 0){
912
perror("sigprocmask");
913
_exit(EXIT_FAILURE);
914
}
915
916
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
917
if(ret == -1){
918
perror("dup2");
919
_exit(EXIT_FAILURE);
920
}
921
922
if(dirfd(dir) < 0){
923
/* If dir has no file descriptor, we could not set FD_CLOEXEC
924
above and must now close it manually here. */
925
closedir(dir);
926
}
927
if(p->environ[0] == NULL){
928
if(execv(filename, p->argv) < 0){
929
perror("execv");
930
_exit(EXIT_FAILURE);
931
}
932
} else {
933
if(execve(filename, p->argv, p->environ) < 0){
934
perror("execve");
935
_exit(EXIT_FAILURE);
936
}
937
}
938
/* no return */
939
}
940
/* Parent process */
941
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
942
pipe */
943
free(filename);
944
plugin *new_plugin = getplugin(dirst->d_name);
945
if(new_plugin == NULL){
946
perror("getplugin");
947
ret = (int)(TEMP_FAILURE_RETRY
948
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
949
NULL)));
950
if(ret < 0){
951
perror("sigprocmask");
952
}
953
exitstatus = EXIT_FAILURE;
954
goto fallback;
955
}
956
957
new_plugin->pid = pid;
958
new_plugin->fd = pipefd[0];
959
960
/* Unblock SIGCHLD so signal handler can be run if this process
961
has already completed */
962
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
963
&sigchld_action.sa_mask,
964
NULL));
965
if(ret < 0){
966
perror("sigprocmask");
967
exitstatus = EXIT_FAILURE;
968
goto fallback;
969
}
970
971
FD_SET(new_plugin->fd, &rfds_all);
972
973
if(maxfd < new_plugin->fd){
974
maxfd = new_plugin->fd;
975
}
976
}
977
978
TEMP_FAILURE_RETRY(closedir(dir));
979
dir = NULL;
980
free_plugin(getplugin(NULL));
981
982
for(plugin *p = plugin_list; p != NULL; p = p->next){
983
if(p->pid != 0){
984
break;
985
}
986
if(p->next == NULL){
987
fprintf(stderr, "No plugin processes started. Incorrect plugin"
988
" directory?\n");
989
free_plugin_list();
990
}
991
}
992
993
/* Main loop while running plugins exist */
994
while(plugin_list){
995
fd_set rfds = rfds_all;
996
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
997
if(select_ret == -1 and errno != EINTR){
998
perror("select");
999
exitstatus = EXIT_FAILURE;
1000
goto fallback;
1001
}
1002
/* OK, now either a process completed, or something can be read
1003
from one of them */
1004
for(plugin *proc = plugin_list; proc != NULL;){
1005
/* Is this process completely done? */
1006
if(proc->completed and proc->eof){
1007
/* Only accept the plugin output if it exited cleanly */
1008
if(not WIFEXITED(proc->status)
1009
or WEXITSTATUS(proc->status) != 0){
1010
/* Bad exit by plugin */
1011
1012
if(debug){
1013
if(WIFEXITED(proc->status)){
1014
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1015
" status %d\n", proc->name,
1016
(intmax_t) (proc->pid),
1017
WEXITSTATUS(proc->status));
1018
} else if(WIFSIGNALED(proc->status)){
1019
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1020
" signal %d: %s\n", proc->name,
1021
(intmax_t) (proc->pid),
1022
WTERMSIG(proc->status),
1023
strsignal(WTERMSIG(proc->status)));
1024
} else if(WCOREDUMP(proc->status)){
1025
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1026
" core\n", proc->name, (intmax_t) (proc->pid));
1027
}
1028
}
1029
1030
/* Remove the plugin */
1031
FD_CLR(proc->fd, &rfds_all);
1032
1033
/* Block signal while modifying process_list */
1034
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1035
(SIG_BLOCK,
1036
&sigchld_action.sa_mask,
1037
NULL));
1038
if(ret < 0){
1039
perror("sigprocmask");
1040
exitstatus = EXIT_FAILURE;
1041
goto fallback;
1042
}
1043
1044
plugin *next_plugin = proc->next;
1045
free_plugin(proc);
1046
proc = next_plugin;
1047
1048
/* We are done modifying process list, so unblock signal */
1049
ret = (int)(TEMP_FAILURE_RETRY
1050
(sigprocmask(SIG_UNBLOCK,
1051
&sigchld_action.sa_mask, NULL)));
1052
if(ret < 0){
1053
perror("sigprocmask");
1054
exitstatus = EXIT_FAILURE;
1055
goto fallback;
1056
}
1057
1058
if(plugin_list == NULL){
1059
break;
1060
}
1061
1062
continue;
1063
}
1064
1065
/* This process exited nicely, so print its buffer */
1066
1067
bool bret = print_out_password(proc->buffer,
1068
proc->buffer_length);
1069
if(not bret){
1070
perror("print_out_password");
1071
exitstatus = EXIT_FAILURE;
1072
}
1073
goto fallback;
1074
}
1075
1076
/* This process has not completed. Does it have any output? */
1077
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1078
/* This process had nothing to say at this time */
1079
proc = proc->next;
1080
continue;
1081
}
1082
/* Before reading, make the process' data buffer large enough */
1083
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1084
proc->buffer = realloc(proc->buffer, proc->buffer_size
1085
+ (size_t) BUFFER_SIZE);
1086
if(proc->buffer == NULL){
1087
perror("malloc");
1088
exitstatus = EXIT_FAILURE;
1089
goto fallback;
1090
}
1091
proc->buffer_size += BUFFER_SIZE;
1092
}
1093
/* Read from the process */
1094
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1095
proc->buffer
1096
+ proc->buffer_length,
1097
BUFFER_SIZE));
1098
if(sret < 0){
1099
/* Read error from this process; ignore the error */
1100
proc = proc->next;
1101
continue;
1102
}
1103
if(sret == 0){
1104
/* got EOF */
1105
proc->eof = true;
1106
} else {
1107
proc->buffer_length += (size_t) sret;
1108
}
1109
}
1110
}
1111
1112
1113
fallback:
1114
1115
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1116
/* Fallback if all plugins failed, none are found or an error
1117
occured */
1118
bool bret;
1119
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1120
char *passwordbuffer = getpass("Password: ");
1121
size_t len = strlen(passwordbuffer);
1122
/* Strip trailing newline */
1123
if(len > 0 and passwordbuffer[len-1] == '\n'){
1124
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1125
len--;
1126
}
1127
bret = print_out_password(passwordbuffer, len);
1128
if(not bret){
1129
perror("print_out_password");
1130
exitstatus = EXIT_FAILURE;
1131
}
1132
}
1133
1134
/* Restore old signal handler */
1135
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1136
if(ret == -1){
1137
perror("sigaction");
1138
exitstatus = EXIT_FAILURE;
1139
}
1140
1141
if(custom_argv != NULL){
1142
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1143
free(*arg);
1144
}
1145
free(custom_argv);
1146
}
1147
1148
if(dir != NULL){
1149
closedir(dir);
1150
}
1151
1152
/* Kill the processes */
1153
for(plugin *p = plugin_list; p != NULL; p = p->next){
1154
if(p->pid != 0){
1155
close(p->fd);
1156
ret = kill(p->pid, SIGTERM);
1157
if(ret == -1 and errno != ESRCH){
1158
/* Set-uid proccesses might not get closed */
1159
perror("kill");
1160
}
1161
}
1162
}
1163
1164
/* Wait for any remaining child processes to terminate */
1165
do {
1166
ret = wait(NULL);
1167
} while(ret >= 0);
1168
if(errno != ECHILD){
1169
perror("wait");
1170
}
1171
1172
free_plugin_list();
1173
1174
free(plugindir);
1175
free(argfile);
1176
1177
return exitstatus;
1178
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0