To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/trunk
« back to all changes in this revision
Viewing changes to plugin-runner.c
- browse files at revision 232
- compare with another revision
- download diff
- download tarball
- view history from revision 232
- Committer: Teddy Hogeborn
- Date: 2008-10-17 18:56:25 UTC
- Revision ID: teddy@fukt.bsnet.se-20081017185625-xrfv8oevzm7lyvl6
Tags: version-1.0.2-1
* Makefile (version): Changed to "1.0.2".
* NEWS (Version 1.0.2): New entry.
* debian/changelog (1.0.2-1): New entry.
* NEWS (Version 1.0.2): New entry.
* debian/changelog (1.0.2-1): New entry.
- files added:
- .bzr-builddeb
- debian
- debian/po
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- plugbasedclient.c => plugin-runner.c
- plugins.d/mandosclient.c => plugins.d/mandos-client.c
- plugins.d/passprompt.c => plugins.d/password-prompt.c
- files modified:
- Makefile
added
removed
plugin-runner.c
1
#include <stdio.h> /* popen, fileno */
2
#include <iso646.h> /* and, or, not */
3
#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
4
WIFEXITED, WEXITSTATUS, wait */
5
#include <sys/wait.h> /* wait */
6
#include <dirent.h> /* DIR, opendir */
7
#include <sys/stat.h> /* stat, struct stat */
8
#include <unistd.h> /* stat, struct stat, chdir */
9
#include <stdlib.h> /* EXIT_FAILURE */
10
#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET, FD_ISSET */
11
#include <string.h> /* strlen, strcpy, strcat */
12
#include <stdbool.h> /* true */
13
#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
14
#include <errno.h> /* errno */
15
16
struct process;
17
18
typedef struct process{
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2008 Teddy Hogeborn & Björn Påhlsson
6
*
7
* This program is free software: you can redistribute it and/or
8
* modify it under the terms of the GNU General Public License as
9
* published by the Free Software Foundation, either version 3 of the
10
* License, or (at your option) any later version.
11
*
12
* This program is distributed in the hope that it will be useful, but
13
* WITHOUT ANY WARRANTY; without even the implied warranty of
14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15
* General Public License for more details.
16
*
17
* You should have received a copy of the GNU General Public License
18
* along with this program. If not, see
19
* <http://www.gnu.org/licenses/>.
20
*
21
* Contact the authors at <mandos@fukt.bsnet.se>.
22
*/
23
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
25
asprintf() */
26
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, fileno(), fprintf(),
31
stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
stat, waitpid(), WIFEXITED(),
34
WEXITSTATUS(), wait(), pid_t,
35
uid_t, gid_t, getuid(), getgid(),
36
dirfd() */
37
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
FD_SET(), FD_ISSET(), FD_CLR */
39
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
40
WEXITSTATUS() */
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
44
readdir(), closedir(), dirfd() */
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
46
fcntl(), setuid(), setgid(),
47
F_GETFD, F_SETFD, FD_CLOEXEC,
48
access(), pipe(), fork(), close()
49
dup2(), STDOUT_FILENO, _exit(),
50
execv(), write(), read(),
51
close() */
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC */
54
#include <string.h> /* strsep, strlen(), asprintf() */
55
#include <errno.h> /* errno */
56
#include <argp.h> /* struct argp_option, struct
57
argp_state, struct argp,
58
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG,
60
error_t */
61
#include <signal.h> /* struct sigaction, sigemptyset(),
62
sigaddset(), sigaction(),
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
#include <errno.h> /* errno, EBADF */
66
67
#define BUFFER_SIZE 256
68
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
71
72
const char *argp_program_version = "plugin-runner " VERSION;
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
75
typedef struct plugin{
76
char *name; /* can be NULL or any plugin name */
77
char **argv;
78
int argc;
79
char **environ;
80
int envc;
81
bool disabled;
82
83
/* Variables used for running processes*/
19
84
pid_t pid;
20
85
int fd;
21
86
char *buffer;
22
int buffer_size;
23
int buffer_length;
24
struct process *next;
25
} process;
26
27
#define BUFFER_SIZE 256
87
size_t buffer_size;
88
size_t buffer_length;
89
bool eof;
90
volatile bool completed;
91
volatile int status;
92
struct plugin *next;
93
} plugin;
94
95
static plugin *plugin_list = NULL;
96
97
/* Gets an existing plugin based on name,
98
or if none is found, creates a new one */
99
static plugin *getplugin(char *name){
100
/* Check for exiting plugin with that name */
101
for (plugin *p = plugin_list; p != NULL; p = p->next){
102
if ((p->name == name)
103
or (p->name and name and (strcmp(p->name, name) == 0))){
104
return p;
105
}
106
}
107
/* Create a new plugin */
108
plugin *new_plugin = malloc(sizeof(plugin));
109
if (new_plugin == NULL){
110
return NULL;
111
}
112
char *copy_name = NULL;
113
if(name != NULL){
114
copy_name = strdup(name);
115
if(copy_name == NULL){
116
return NULL;
117
}
118
}
119
120
*new_plugin = (plugin) { .name = copy_name,
121
.argc = 1,
122
.disabled = false,
123
.next = plugin_list };
124
125
new_plugin->argv = malloc(sizeof(char *) * 2);
126
if (new_plugin->argv == NULL){
127
free(copy_name);
128
free(new_plugin);
129
return NULL;
130
}
131
new_plugin->argv[0] = copy_name;
132
new_plugin->argv[1] = NULL;
133
134
new_plugin->environ = malloc(sizeof(char *));
135
if(new_plugin->environ == NULL){
136
free(copy_name);
137
free(new_plugin->argv);
138
free(new_plugin);
139
return NULL;
140
}
141
new_plugin->environ[0] = NULL;
142
143
/* Append the new plugin to the list */
144
plugin_list = new_plugin;
145
return new_plugin;
146
}
147
148
/* Helper function for add_argument and add_environment */
149
static bool add_to_char_array(const char *new, char ***array,
150
int *len){
151
/* Resize the pointed-to array to hold one more pointer */
152
*array = realloc(*array, sizeof(char *)
153
* (size_t) ((*len) + 2));
154
/* Malloc check */
155
if(*array == NULL){
156
return false;
157
}
158
/* Make a copy of the new string */
159
char *copy = strdup(new);
160
if(copy == NULL){
161
return false;
162
}
163
/* Insert the copy */
164
(*array)[*len] = copy;
165
(*len)++;
166
/* Add a new terminating NULL pointer to the last element */
167
(*array)[*len] = NULL;
168
return true;
169
}
170
171
/* Add to a plugin's argument vector */
172
static bool add_argument(plugin *p, const char *arg){
173
if(p == NULL){
174
return false;
175
}
176
return add_to_char_array(arg, &(p->argv), &(p->argc));
177
}
178
179
/* Add to a plugin's environment */
180
static bool add_environment(plugin *p, const char *def, bool replace){
181
if(p == NULL){
182
return false;
183
}
184
/* namelen = length of name of environment variable */
185
size_t namelen = (size_t)(strchrnul(def, '=') - def);
186
/* Search for this environment variable */
187
for(char **e = p->environ; *e != NULL; e++){
188
if(strncmp(*e, def, namelen + 1) == 0){
189
/* It already exists */
190
if(replace){
191
char *new = realloc(*e, strlen(def) + 1);
192
if(new == NULL){
193
return false;
194
}
195
*e = new;
196
strcpy(*e, def);
197
}
198
return true;
199
}
200
}
201
return add_to_char_array(def, &(p->environ), &(p->envc));
202
}
203
204
/*
205
* Based on the example in the GNU LibC manual chapter 13.13 "File
206
* Descriptor Flags".
207
* *Note File Descriptor Flags:(libc)Descriptor Flags.
208
*/
209
static int set_cloexec_flag(int fd){
210
int ret = fcntl(fd, F_GETFD, 0);
211
/* If reading the flags failed, return error indication now. */
212
if(ret < 0){
213
return ret;
214
}
215
/* Store modified flag word in the descriptor. */
216
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
217
}
218
219
220
/* Mark processes as completed when they exit, and save their exit
221
status. */
222
static void handle_sigchld(__attribute__((unused)) int sig){
223
while(true){
224
plugin *proc = plugin_list;
225
int status;
226
pid_t pid = waitpid(-1, &status, WNOHANG);
227
if(pid == 0){
228
/* Only still running child processes */
229
break;
230
}
231
if(pid == -1){
232
if (errno != ECHILD){
233
perror("waitpid");
234
}
235
/* No child processes */
236
break;
237
}
238
239
/* A child exited, find it in process_list */
240
while(proc != NULL and proc->pid != pid){
241
proc = proc->next;
242
}
243
if(proc == NULL){
244
/* Process not found in process list */
245
continue;
246
}
247
proc->status = status;
248
proc->completed = true;
249
}
250
}
251
252
/* Prints out a password to stdout */
253
static bool print_out_password(const char *buffer, size_t length){
254
ssize_t ret;
255
for(size_t written = 0; written < length; written += (size_t)ret){
256
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
257
length - written));
258
if(ret < 0){
259
return false;
260
}
261
}
262
return true;
263
}
264
265
/* Removes and free a plugin from the plugin list */
266
static void free_plugin(plugin *plugin_node){
267
268
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
269
free(*arg);
270
}
271
free(plugin_node->argv);
272
for(char **env = plugin_node->environ; *env != NULL; env++){
273
free(*env);
274
}
275
free(plugin_node->environ);
276
free(plugin_node->buffer);
277
278
/* Removes the plugin from the singly-linked list */
279
if(plugin_node == plugin_list){
280
/* First one - simple */
281
plugin_list = plugin_list->next;
282
} else {
283
/* Second one or later */
284
for(plugin *p = plugin_list; p != NULL; p = p->next){
285
if(p->next == plugin_node){
286
p->next = plugin_node->next;
287
break;
288
}
289
}
290
}
291
292
free(plugin_node);
293
}
294
295
static void free_plugin_list(void){
296
while(plugin_list != NULL){
297
free_plugin(plugin_list);
298
}
299
}
28
300
29
301
int main(int argc, char *argv[]){
30
char plugindir[] = "plugins.d";
31
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
32
DIR *dir;
302
char *plugindir = NULL;
303
char *argfile = NULL;
304
FILE *conffp;
305
size_t d_name_len;
306
DIR *dir = NULL;
33
307
struct dirent *dirst;
34
308
struct stat st;
35
fd_set rfds_orig;
309
fd_set rfds_all;
36
310
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
311
uid_t uid = 65534;
312
gid_t gid = 65534;
313
bool debug = false;
314
int exitstatus = EXIT_SUCCESS;
315
struct sigaction old_sigchld_action;
316
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
317
.sa_flags = SA_NOCLDSTOP };
318
char **custom_argv = NULL;
319
int custom_argc = 0;
320
321
/* Establish a signal handler */
322
sigemptyset(&sigchld_action.sa_mask);
323
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
324
if(ret == -1){
325
perror("sigaddset");
326
exitstatus = EXIT_FAILURE;
327
goto fallback;
328
}
329
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
330
if(ret == -1){
331
perror("sigaction");
332
exitstatus = EXIT_FAILURE;
333
goto fallback;
334
}
335
336
/* The options we understand. */
337
struct argp_option options[] = {
338
{ .name = "global-options", .key = 'g',
339
.arg = "OPTION[,OPTION[,...]]",
340
.doc = "Options passed to all plugins" },
341
{ .name = "global-env", .key = 'G',
342
.arg = "VAR=value",
343
.doc = "Environment variable passed to all plugins" },
344
{ .name = "options-for", .key = 'o',
345
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
346
.doc = "Options passed only to specified plugin" },
347
{ .name = "env-for", .key = 'E',
348
.arg = "PLUGIN:ENV=value",
349
.doc = "Environment variable passed to specified plugin" },
350
{ .name = "disable", .key = 'd',
351
.arg = "PLUGIN",
352
.doc = "Disable a specific plugin", .group = 1 },
353
{ .name = "enable", .key = 'e',
354
.arg = "PLUGIN",
355
.doc = "Enable a specific plugin", .group = 1 },
356
{ .name = "plugin-dir", .key = 128,
357
.arg = "DIRECTORY",
358
.doc = "Specify a different plugin directory", .group = 2 },
359
{ .name = "config-file", .key = 129,
360
.arg = "FILE",
361
.doc = "Specify a different configuration file", .group = 2 },
362
{ .name = "userid", .key = 130,
363
.arg = "ID", .flags = 0,
364
.doc = "User ID the plugins will run as", .group = 3 },
365
{ .name = "groupid", .key = 131,
366
.arg = "ID", .flags = 0,
367
.doc = "Group ID the plugins will run as", .group = 3 },
368
{ .name = "debug", .key = 132,
369
.doc = "Debug mode", .group = 4 },
370
{ .name = NULL }
371
};
372
373
error_t parse_opt (int key, char *arg, __attribute__((unused))
374
struct argp_state *state) {
375
switch (key) {
376
case 'g': /* --global-options */
377
if (arg != NULL){
378
char *p;
379
while((p = strsep(&arg, ",")) != NULL){
380
if(p[0] == '\0'){
381
continue;
382
}
383
if(not add_argument(getplugin(NULL), p)){
384
perror("add_argument");
385
return ARGP_ERR_UNKNOWN;
386
}
387
}
388
}
389
break;
390
case 'G': /* --global-env */
391
if(arg == NULL){
392
break;
393
}
394
if(not add_environment(getplugin(NULL), arg, true)){
395
perror("add_environment");
396
}
397
break;
398
case 'o': /* --options-for */
399
if (arg != NULL){
400
char *p_name = strsep(&arg, ":");
401
if(p_name[0] == '\0' or arg == NULL){
402
break;
403
}
404
char *opt = strsep(&arg, ":");
405
if(opt[0] == '\0' or opt == NULL){
406
break;
407
}
408
char *p;
409
while((p = strsep(&opt, ",")) != NULL){
410
if(p[0] == '\0'){
411
continue;
412
}
413
if(not add_argument(getplugin(p_name), p)){
414
perror("add_argument");
415
return ARGP_ERR_UNKNOWN;
416
}
417
}
418
}
419
break;
420
case 'E': /* --env-for */
421
if(arg == NULL){
422
break;
423
}
424
{
425
char *envdef = strchr(arg, ':');
426
if(envdef == NULL){
427
break;
428
}
429
*envdef = '\0';
430
if(not add_environment(getplugin(arg), envdef+1, true)){
431
perror("add_environment");
432
}
433
}
434
break;
435
case 'd': /* --disable */
436
if (arg != NULL){
437
plugin *p = getplugin(arg);
438
if(p == NULL){
439
return ARGP_ERR_UNKNOWN;
440
}
441
p->disabled = true;
442
}
443
break;
444
case 'e': /* --enable */
445
if (arg != NULL){
446
plugin *p = getplugin(arg);
447
if(p == NULL){
448
return ARGP_ERR_UNKNOWN;
449
}
450
p->disabled = false;
451
}
452
break;
453
case 128: /* --plugin-dir */
454
free(plugindir);
455
plugindir = strdup(arg);
456
if(plugindir == NULL){
457
perror("strdup");
458
}
459
break;
460
case 129: /* --config-file */
461
/* This is already done by parse_opt_config_file() */
462
break;
463
case 130: /* --userid */
464
uid = (uid_t)strtol(arg, NULL, 10);
465
break;
466
case 131: /* --groupid */
467
gid = (gid_t)strtol(arg, NULL, 10);
468
break;
469
case 132: /* --debug */
470
debug = true;
471
break;
472
case ARGP_KEY_ARG:
473
/* Cryptsetup always passes an argument, which is an empty
474
string if "none" was specified in /etc/crypttab. So if
475
argument was empty, we ignore it silently. */
476
if(arg[0] != '\0'){
477
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
478
}
479
break;
480
case ARGP_KEY_END:
481
break;
482
default:
483
return ARGP_ERR_UNKNOWN;
484
}
485
return 0;
486
}
487
488
/* This option parser is the same as parse_opt() above, except it
489
ignores everything but the --config-file option. */
490
error_t parse_opt_config_file (int key, char *arg,
491
__attribute__((unused))
492
struct argp_state *state) {
493
switch (key) {
494
case 'g': /* --global-options */
495
case 'G': /* --global-env */
496
case 'o': /* --options-for */
497
case 'E': /* --env-for */
498
case 'd': /* --disable */
499
case 'e': /* --enable */
500
case 128: /* --plugin-dir */
501
break;
502
case 129: /* --config-file */
503
free(argfile);
504
argfile = strdup(arg);
505
if(argfile == NULL){
506
perror("strdup");
507
}
508
break;
509
case 130: /* --userid */
510
case 131: /* --groupid */
511
case 132: /* --debug */
512
case ARGP_KEY_ARG:
513
case ARGP_KEY_END:
514
break;
515
default:
516
return ARGP_ERR_UNKNOWN;
517
}
518
return 0;
519
}
520
521
struct argp argp = { .options = options,
522
.parser = parse_opt_config_file,
523
.args_doc = "",
524
.doc = "Mandos plugin runner -- Run plugins" };
525
526
/* Parse using the parse_opt_config_file in order to get the custom
527
config file location, if any. */
528
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
529
if (ret == ARGP_ERR_UNKNOWN){
530
fprintf(stderr, "Unknown error while parsing arguments\n");
531
exitstatus = EXIT_FAILURE;
532
goto fallback;
533
}
534
535
/* Reset to the normal argument parser */
536
argp.parser = parse_opt;
537
538
/* Open the configfile if available */
539
if (argfile == NULL){
540
conffp = fopen(AFILE, "r");
541
} else {
542
conffp = fopen(argfile, "r");
543
}
544
if(conffp != NULL){
545
char *org_line = NULL;
546
char *p, *arg, *new_arg, *line;
547
size_t size = 0;
548
ssize_t sret;
549
const char whitespace_delims[] = " \r\t\f\v\n";
550
const char comment_delim[] = "#";
551
552
custom_argc = 1;
553
custom_argv = malloc(sizeof(char*) * 2);
554
if(custom_argv == NULL){
555
perror("malloc");
556
exitstatus = EXIT_FAILURE;
557
goto fallback;
558
}
559
custom_argv[0] = argv[0];
560
custom_argv[1] = NULL;
561
562
/* for each line in the config file, strip whitespace and ignore
563
commented text */
564
while(true){
565
sret = getline(&org_line, &size, conffp);
566
if(sret == -1){
567
break;
568
}
569
570
line = org_line;
571
arg = strsep(&line, comment_delim);
572
while((p = strsep(&arg, whitespace_delims)) != NULL){
573
if(p[0] == '\0'){
574
continue;
575
}
576
new_arg = strdup(p);
577
if(new_arg == NULL){
578
perror("strdup");
579
exitstatus = EXIT_FAILURE;
580
free(org_line);
581
goto fallback;
582
}
583
584
custom_argc += 1;
585
custom_argv = realloc(custom_argv, sizeof(char *)
586
* ((unsigned int) custom_argc + 1));
587
if(custom_argv == NULL){
588
perror("realloc");
589
exitstatus = EXIT_FAILURE;
590
free(org_line);
591
goto fallback;
592
}
593
custom_argv[custom_argc-1] = new_arg;
594
custom_argv[custom_argc] = NULL;
595
}
596
}
597
free(org_line);
598
} else {
599
/* Check for harmful errors and go to fallback. Other errors might
600
not affect opening plugins */
601
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
602
perror("fopen");
603
exitstatus = EXIT_FAILURE;
604
goto fallback;
605
}
606
}
607
/* If there was any arguments from configuration file,
608
pass them to parser as command arguments */
609
if(custom_argv != NULL){
610
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
611
0, NULL);
612
if (ret == ARGP_ERR_UNKNOWN){
613
fprintf(stderr, "Unknown error while parsing arguments\n");
614
exitstatus = EXIT_FAILURE;
615
goto fallback;
616
}
617
}
618
619
/* Parse actual command line arguments, to let them override the
620
config file */
621
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
622
if (ret == ARGP_ERR_UNKNOWN){
623
fprintf(stderr, "Unknown error while parsing arguments\n");
624
exitstatus = EXIT_FAILURE;
625
goto fallback;
626
}
627
628
if(debug){
629
for(plugin *p = plugin_list; p != NULL; p=p->next){
630
fprintf(stderr, "Plugin: %s has %d arguments\n",
631
p->name ? p->name : "Global", p->argc - 1);
632
for(char **a = p->argv; *a != NULL; a++){
633
fprintf(stderr, "\tArg: %s\n", *a);
634
}
635
fprintf(stderr, "...and %u environment variables\n", p->envc);
636
for(char **a = p->environ; *a != NULL; a++){
637
fprintf(stderr, "\t%s\n", *a);
638
}
639
}
640
}
641
642
/* Strip permissions down to nobody */
643
ret = setuid(uid);
644
if (ret == -1){
645
perror("setuid");
646
}
647
setgid(gid);
648
if (ret == -1){
649
perror("setgid");
650
}
651
652
if (plugindir == NULL){
653
dir = opendir(PDIR);
654
} else {
655
dir = opendir(plugindir);
656
}
657
41
658
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
659
perror("Could not open plugin dir");
660
exitstatus = EXIT_FAILURE;
661
goto fallback;
662
}
663
664
/* Set the FD_CLOEXEC flag on the directory, if possible */
665
{
666
int dir_fd = dirfd(dir);
667
if(dir_fd >= 0){
668
ret = set_cloexec_flag(dir_fd);
669
if(ret < 0){
670
perror("set_cloexec_flag");
671
exitstatus = EXIT_FAILURE;
672
goto fallback;
673
}
674
}
675
}
676
677
FD_ZERO(&rfds_all);
678
679
/* Read and execute any executable in the plugin directory*/
48
680
while(true){
49
681
dirst = readdir(dir);
50
682
51
// All directory entries have been processed
683
/* All directory entries have been processed */
52
684
if(dirst == NULL){
685
if (errno == EBADF){
686
perror("readdir");
687
exitstatus = EXIT_FAILURE;
688
goto fallback;
689
}
53
690
break;
54
691
}
55
692
56
693
d_name_len = strlen(dirst->d_name);
57
694
58
// Ignore dotfiles and backup files
59
if (dirst->d_name[0] == '.'
60
or dirst->d_name[d_name_len - 1] == '~'){
61
continue;
62
}
63
64
char *filename = malloc(d_name_len + plugindir_len + 2);
65
strcpy(filename, plugindir);
66
strcat(filename, "/");
67
strcat(filename, dirst->d_name);
68
69
stat(filename, &st);
70
71
if (S_ISREG(st.st_mode) and (access(filename, X_OK) == 0)){
72
// Starting a new process to be watched
73
process *new_process = malloc(sizeof(process));
74
int pipefd[2];
75
pipe(pipefd);
76
new_process->pid = fork();
77
if(new_process->pid == 0){
78
/* this is the child process */
695
/* Ignore dotfiles, backup files and other junk */
696
{
697
bool bad_name = false;
698
699
const char const *bad_prefixes[] = { ".", "#", NULL };
700
701
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
702
".dpkg-old",
703
".dpkg-divert", NULL };
704
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
705
size_t pre_len = strlen(*pre);
706
if((d_name_len >= pre_len)
707
and strncmp((dirst->d_name), *pre, pre_len) == 0){
708
if(debug){
709
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
710
" with bad prefix %s\n", dirst->d_name, *pre);
711
}
712
bad_name = true;
713
break;
714
}
715
}
716
if(bad_name){
717
continue;
718
}
719
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
720
size_t suf_len = strlen(*suf);
721
if((d_name_len >= suf_len)
722
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
723
== 0)){
724
if(debug){
725
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
726
" with bad suffix %s\n", dirst->d_name, *suf);
727
}
728
bad_name = true;
729
break;
730
}
731
}
732
733
if(bad_name){
734
continue;
735
}
736
}
737
738
char *filename;
739
if(plugindir == NULL){
740
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
741
} else {
742
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
743
}
744
if(ret < 0){
745
perror("asprintf");
746
continue;
747
}
748
749
ret = stat(filename, &st);
750
if (ret == -1){
751
perror("stat");
752
free(filename);
753
continue;
754
}
755
756
/* Ignore non-executable files */
757
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
758
if(debug){
759
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
760
" with bad type or mode\n", filename);
761
}
762
free(filename);
763
continue;
764
}
765
766
plugin *p = getplugin(dirst->d_name);
767
if(p == NULL){
768
perror("getplugin");
769
free(filename);
770
continue;
771
}
772
if(p->disabled){
773
if(debug){
774
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
775
dirst->d_name);
776
}
777
free(filename);
778
continue;
779
}
780
{
781
/* Add global arguments to argument list for this plugin */
782
plugin *g = getplugin(NULL);
783
if(g != NULL){
784
for(char **a = g->argv + 1; *a != NULL; a++){
785
if(not add_argument(p, *a)){
786
perror("add_argument");
787
}
788
}
789
/* Add global environment variables */
790
for(char **e = g->environ; *e != NULL; e++){
791
if(not add_environment(p, *e, false)){
792
perror("add_environment");
793
}
794
}
795
}
796
}
797
/* If this plugin has any environment variables, we will call
798
using execve and need to duplicate the environment from this
799
process, too. */
800
if(p->environ[0] != NULL){
801
for(char **e = environ; *e != NULL; e++){
802
if(not add_environment(p, *e, false)){
803
perror("add_environment");
804
}
805
}
806
}
807
808
int pipefd[2];
809
ret = pipe(pipefd);
810
if (ret == -1){
811
perror("pipe");
812
exitstatus = EXIT_FAILURE;
813
goto fallback;
814
}
815
/* Ask OS to automatic close the pipe on exec */
816
ret = set_cloexec_flag(pipefd[0]);
817
if(ret < 0){
818
perror("set_cloexec_flag");
819
exitstatus = EXIT_FAILURE;
820
goto fallback;
821
}
822
ret = set_cloexec_flag(pipefd[1]);
823
if(ret < 0){
824
perror("set_cloexec_flag");
825
exitstatus = EXIT_FAILURE;
826
goto fallback;
827
}
828
/* Block SIGCHLD until process is safely in process list */
829
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
830
if(ret < 0){
831
perror("sigprocmask");
832
exitstatus = EXIT_FAILURE;
833
goto fallback;
834
}
835
/* Starting a new process to be watched */
836
pid_t pid = fork();
837
if(pid == -1){
838
perror("fork");
839
exitstatus = EXIT_FAILURE;
840
goto fallback;
841
}
842
if(pid == 0){
843
/* this is the child process */
844
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
845
if(ret < 0){
846
perror("sigaction");
847
_exit(EXIT_FAILURE);
848
}
849
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
850
if(ret < 0){
851
perror("sigprocmask");
852
_exit(EXIT_FAILURE);
853
}
854
855
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
856
if(ret == -1){
857
perror("dup2");
858
_exit(EXIT_FAILURE);
859
}
860
861
if(dirfd(dir) < 0){
862
/* If dir has no file descriptor, we could not set FD_CLOEXEC
863
above and must now close it manually here. */
79
864
closedir(dir);
80
close(pipefd[0]); /* close unused read end of pipe */
81
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
82
/* create a new modified argument list */
83
char **new_argv = malloc(sizeof(char *) * (argc + 1));
84
new_argv[0] = filename;
85
for(int i = 1; i < argc; i++){
86
new_argv[i] = argv[i];
87
}
88
new_argv[argc] = NULL;
89
if(execv(filename, new_argv) < 0){
90
perror(argv[0]);
91
close(pipefd[1]);
92
exit(EXIT_FAILURE);
93
}
94
/* no return */
95
}
96
close(pipefd[1]); /* close unused write end of pipe */
97
new_process->fd = pipefd[0];
98
new_process->buffer = malloc(BUFFER_SIZE);
99
if (new_process->buffer == NULL){
100
perror(argv[0]);
101
goto end;
102
}
103
new_process->buffer_size = BUFFER_SIZE;
104
new_process->buffer_length = 0;
105
FD_SET(new_process->fd, &rfds_orig);
106
107
if (maxfd < new_process->fd){
108
maxfd = new_process->fd;
109
}
110
111
//List handling
112
new_process->next = process_list;
113
process_list = new_process;
865
}
866
if(p->environ[0] == NULL){
867
if(execv(filename, p->argv) < 0){
868
perror("execv");
869
_exit(EXIT_FAILURE);
870
}
871
} else {
872
if(execve(filename, p->argv, p->environ) < 0){
873
perror("execve");
874
_exit(EXIT_FAILURE);
875
}
876
}
877
/* no return */
878
}
879
/* Parent process */
880
close(pipefd[1]); /* Close unused write end of pipe */
881
free(filename);
882
plugin *new_plugin = getplugin(dirst->d_name);
883
if (new_plugin == NULL){
884
perror("getplugin");
885
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
886
if(ret < 0){
887
perror("sigprocmask");
888
}
889
exitstatus = EXIT_FAILURE;
890
goto fallback;
891
}
892
893
new_plugin->pid = pid;
894
new_plugin->fd = pipefd[0];
895
896
/* Unblock SIGCHLD so signal handler can be run if this process
897
has already completed */
898
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
899
if(ret < 0){
900
perror("sigprocmask");
901
exitstatus = EXIT_FAILURE;
902
goto fallback;
903
}
904
905
FD_SET(new_plugin->fd, &rfds_all);
906
907
if (maxfd < new_plugin->fd){
908
maxfd = new_plugin->fd;
114
909
}
115
910
}
116
911
117
912
closedir(dir);
118
119
if (process_list != NULL){
120
while(true){
121
fd_set rfds = rfds_orig;
122
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
123
if (select_ret == -1){
124
perror(argv[0]);
125
goto end;
126
}else{
127
for(process *process_itr = process_list; process_itr != NULL;
128
process_itr = process_itr->next){
129
if(FD_ISSET(process_itr->fd, &rfds)){
130
if(process_itr->buffer_length + BUFFER_SIZE
131
> process_itr->buffer_size){
132
process_itr->buffer = realloc(process_itr->buffer,
133
process_itr->buffer_size
134
+ BUFFER_SIZE);
135
if (process_itr->buffer == NULL){
136
perror(argv[0]);
137
goto end;
138
}
139
process_itr->buffer_size += BUFFER_SIZE;
140
}
141
ret = read(process_itr->fd, process_itr->buffer
142
+ process_itr->buffer_length, BUFFER_SIZE);
143
process_itr->buffer_length+=ret;
144
if(ret == 0){
145
/* got EOF */
146
/* wait for process exit */
147
int status;
148
waitpid(process_itr->pid, &status, 0);
149
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
150
write(STDOUT_FILENO, process_itr->buffer,
151
process_itr->buffer_length);
152
goto end;
153
} else {
154
FD_CLR(process_itr->fd, &rfds_orig);
155
}
156
}
157
}
158
}
159
}
160
}
161
}
162
163
end:
164
for(process *process_itr = process_list; process_itr != NULL;
165
process_itr = process_itr->next){
166
close(process_itr->fd);
167
kill(process_itr->pid, SIGTERM);
168
free(process_itr->buffer);
169
}
170
171
while(true){
172
int status;
173
ret = wait(&status);
174
if (ret == -1){
175
if(errno != ECHILD){
176
perror("wait");
177
}
913
dir = NULL;
914
915
for(plugin *p = plugin_list; p != NULL; p = p->next){
916
if(p->pid != 0){
178
917
break;
179
918
}
180
}
181
return EXIT_SUCCESS;
919
if(p->next == NULL){
920
fprintf(stderr, "No plugin processes started. Incorrect plugin"
921
" directory?\n");
922
free_plugin_list();
923
}
924
}
925
926
/* Main loop while running plugins exist */
927
while(plugin_list){
928
fd_set rfds = rfds_all;
929
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
930
if (select_ret == -1){
931
perror("select");
932
exitstatus = EXIT_FAILURE;
933
goto fallback;
934
}
935
/* OK, now either a process completed, or something can be read
936
from one of them */
937
for(plugin *proc = plugin_list; proc != NULL;){
938
/* Is this process completely done? */
939
if(proc->eof and proc->completed){
940
/* Only accept the plugin output if it exited cleanly */
941
if(not WIFEXITED(proc->status)
942
or WEXITSTATUS(proc->status) != 0){
943
/* Bad exit by plugin */
944
945
if(debug){
946
if(WIFEXITED(proc->status)){
947
fprintf(stderr, "Plugin %u exited with status %d\n",
948
(unsigned int) (proc->pid),
949
WEXITSTATUS(proc->status));
950
} else if(WIFSIGNALED(proc->status)) {
951
fprintf(stderr, "Plugin %u killed by signal %d\n",
952
(unsigned int) (proc->pid),
953
WTERMSIG(proc->status));
954
} else if(WCOREDUMP(proc->status)){
955
fprintf(stderr, "Plugin %d dumped core\n",
956
(unsigned int) (proc->pid));
957
}
958
}
959
960
/* Remove the plugin */
961
FD_CLR(proc->fd, &rfds_all);
962
963
/* Block signal while modifying process_list */
964
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
965
if(ret < 0){
966
perror("sigprocmask");
967
exitstatus = EXIT_FAILURE;
968
goto fallback;
969
}
970
971
plugin *next_plugin = proc->next;
972
free_plugin(proc);
973
proc = next_plugin;
974
975
/* We are done modifying process list, so unblock signal */
976
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
977
NULL);
978
if(ret < 0){
979
perror("sigprocmask");
980
exitstatus = EXIT_FAILURE;
981
goto fallback;
982
}
983
984
if(plugin_list == NULL){
985
break;
986
}
987
988
continue;
989
}
990
991
/* This process exited nicely, so print its buffer */
992
993
bool bret = print_out_password(proc->buffer,
994
proc->buffer_length);
995
if(not bret){
996
perror("print_out_password");
997
exitstatus = EXIT_FAILURE;
998
}
999
goto fallback;
1000
}
1001
1002
/* This process has not completed. Does it have any output? */
1003
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1004
/* This process had nothing to say at this time */
1005
proc = proc->next;
1006
continue;
1007
}
1008
/* Before reading, make the process' data buffer large enough */
1009
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1010
proc->buffer = realloc(proc->buffer, proc->buffer_size
1011
+ (size_t) BUFFER_SIZE);
1012
if (proc->buffer == NULL){
1013
perror("malloc");
1014
exitstatus = EXIT_FAILURE;
1015
goto fallback;
1016
}
1017
proc->buffer_size += BUFFER_SIZE;
1018
}
1019
/* Read from the process */
1020
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1021
BUFFER_SIZE);
1022
if(ret < 0){
1023
/* Read error from this process; ignore the error */
1024
proc = proc->next;
1025
continue;
1026
}
1027
if(ret == 0){
1028
/* got EOF */
1029
proc->eof = true;
1030
} else {
1031
proc->buffer_length += (size_t) ret;
1032
}
1033
}
1034
}
1035
1036
1037
fallback:
1038
1039
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1040
/* Fallback if all plugins failed, none are found or an error
1041
occured */
1042
bool bret;
1043
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1044
char *passwordbuffer = getpass("Password: ");
1045
size_t len = strlen(passwordbuffer);
1046
/* Strip trailing newline */
1047
if(len > 0 and passwordbuffer[len-1] == '\n'){
1048
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1049
len--;
1050
}
1051
bret = print_out_password(passwordbuffer, len);
1052
if(not bret){
1053
perror("print_out_password");
1054
exitstatus = EXIT_FAILURE;
1055
}
1056
}
1057
1058
/* Restore old signal handler */
1059
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1060
if(ret == -1){
1061
perror("sigaction");
1062
exitstatus = EXIT_FAILURE;
1063
}
1064
1065
if(custom_argv != NULL){
1066
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1067
free(*arg);
1068
}
1069
free(custom_argv);
1070
}
1071
1072
if(dir != NULL){
1073
closedir(dir);
1074
}
1075
1076
/* Kill the processes */
1077
for(plugin *p = plugin_list; p != NULL; p = p->next){
1078
if(p->pid != 0){
1079
close(p->fd);
1080
ret = kill(p->pid, SIGTERM);
1081
if(ret == -1 and errno != ESRCH){
1082
/* Set-uid proccesses might not get closed */
1083
perror("kill");
1084
}
1085
}
1086
}
1087
1088
/* Wait for any remaining child processes to terminate */
1089
do{
1090
ret = wait(NULL);
1091
} while(ret >= 0);
1092
if(errno != ECHILD){
1093
perror("wait");
1094
}
1095
1096
free_plugin_list();
1097
1098
free(plugindir);
1099
free(argfile);
1100
1101
return exitstatus;
182
1102
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0