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 287
- compare with another revision
- download diff
- download tarball
- view history from revision 287
- Committer: Teddy Hogeborn
- Date: 2009-01-27 00:07:26 UTC
- Revision ID: teddy@fukt.bsnet.se-20090127000726-4cafcfy35g8kh2b8
* INSTALL (Prerequisites/Mandos Server): Added "PyGObject".
- 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 © 2008,2009 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() */
42
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
readdir(), closedir(), dirfd() */
46
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
47
fcntl(), setuid(), setgid(),
48
F_GETFD, F_SETFD, FD_CLOEXEC,
49
access(), pipe(), fork(), close()
50
dup2(), STDOUT_FILENO, _exit(),
51
execv(), write(), read(),
52
close() */
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
FD_CLOEXEC */
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <errno.h> /* errno */
57
#include <argp.h> /* struct argp_option, struct
58
argp_state, struct argp,
59
argp_parse(), ARGP_ERR_UNKNOWN,
60
ARGP_KEY_END, ARGP_KEY_ARG,
61
error_t */
62
#include <signal.h> /* struct sigaction, sigemptyset(),
63
sigaddset(), sigaction(),
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
65
SIG_UNBLOCK, kill() */
66
#include <errno.h> /* errno, EBADF */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
68
69
#define BUFFER_SIZE 256
70
71
#define PDIR "/lib/mandos/plugins.d"
72
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
73
74
const char *argp_program_version = "plugin-runner " VERSION;
75
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
76
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
79
char **argv;
80
int argc;
81
char **environ;
82
int envc;
83
bool disabled;
84
85
/* Variables used for running processes*/
19
86
pid_t pid;
20
87
int fd;
21
88
char *buffer;
22
int buffer_size;
23
int buffer_length;
24
struct process *next;
25
} process;
26
27
#define BUFFER_SIZE 256
89
size_t buffer_size;
90
size_t buffer_length;
91
bool eof;
92
volatile bool completed;
93
volatile int status;
94
struct plugin *next;
95
} plugin;
96
97
static plugin *plugin_list = NULL;
98
99
/* Gets an existing plugin based on name,
100
or if none is found, creates a new one */
101
static plugin *getplugin(char *name){
102
/* Check for exiting plugin with that name */
103
for(plugin *p = plugin_list; p != NULL; p = p->next){
104
if((p->name == name)
105
or (p->name and name and (strcmp(p->name, name) == 0))){
106
return p;
107
}
108
}
109
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if(new_plugin == NULL){
112
return NULL;
113
}
114
char *copy_name = NULL;
115
if(name != NULL){
116
copy_name = strdup(name);
117
if(copy_name == NULL){
118
free(new_plugin);
119
return NULL;
120
}
121
}
122
123
*new_plugin = (plugin) { .name = copy_name,
124
.argc = 1,
125
.disabled = false,
126
.next = plugin_list };
127
128
new_plugin->argv = malloc(sizeof(char *) * 2);
129
if(new_plugin->argv == NULL){
130
free(copy_name);
131
free(new_plugin);
132
return NULL;
133
}
134
new_plugin->argv[0] = copy_name;
135
new_plugin->argv[1] = NULL;
136
137
new_plugin->environ = malloc(sizeof(char *));
138
if(new_plugin->environ == NULL){
139
free(copy_name);
140
free(new_plugin->argv);
141
free(new_plugin);
142
return NULL;
143
}
144
new_plugin->environ[0] = NULL;
145
146
/* Append the new plugin to the list */
147
plugin_list = new_plugin;
148
return new_plugin;
149
}
150
151
/* Helper function for add_argument and add_environment */
152
static bool add_to_char_array(const char *new, char ***array,
153
int *len){
154
/* Resize the pointed-to array to hold one more pointer */
155
*array = realloc(*array, sizeof(char *)
156
* (size_t) ((*len) + 2));
157
/* Malloc check */
158
if(*array == NULL){
159
return false;
160
}
161
/* Make a copy of the new string */
162
char *copy = strdup(new);
163
if(copy == NULL){
164
return false;
165
}
166
/* Insert the copy */
167
(*array)[*len] = copy;
168
(*len)++;
169
/* Add a new terminating NULL pointer to the last element */
170
(*array)[*len] = NULL;
171
return true;
172
}
173
174
/* Add to a plugin's argument vector */
175
static bool add_argument(plugin *p, const char *arg){
176
if(p == NULL){
177
return false;
178
}
179
return add_to_char_array(arg, &(p->argv), &(p->argc));
180
}
181
182
/* Add to a plugin's environment */
183
static bool add_environment(plugin *p, const char *def, bool replace){
184
if(p == NULL){
185
return false;
186
}
187
/* namelen = length of name of environment variable */
188
size_t namelen = (size_t)(strchrnul(def, '=') - def);
189
/* Search for this environment variable */
190
for(char **e = p->environ; *e != NULL; e++){
191
if(strncmp(*e, def, namelen + 1) == 0){
192
/* It already exists */
193
if(replace){
194
char *new = realloc(*e, strlen(def) + 1);
195
if(new == NULL){
196
return false;
197
}
198
*e = new;
199
strcpy(*e, def);
200
}
201
return true;
202
}
203
}
204
return add_to_char_array(def, &(p->environ), &(p->envc));
205
}
206
207
/*
208
* Based on the example in the GNU LibC manual chapter 13.13 "File
209
* Descriptor Flags".
210
* *Note File Descriptor Flags:(libc)Descriptor Flags.
211
*/
212
static int set_cloexec_flag(int fd){
213
int ret = fcntl(fd, F_GETFD, 0);
214
/* If reading the flags failed, return error indication now. */
215
if(ret < 0){
216
return ret;
217
}
218
/* Store modified flag word in the descriptor. */
219
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
220
}
221
222
223
/* Mark processes as completed when they exit, and save their exit
224
status. */
225
static void handle_sigchld(__attribute__((unused)) int sig){
226
while(true){
227
plugin *proc = plugin_list;
228
int status;
229
pid_t pid = waitpid(-1, &status, WNOHANG);
230
if(pid == 0){
231
/* Only still running child processes */
232
break;
233
}
234
if(pid == -1){
235
if(errno != ECHILD){
236
perror("waitpid");
237
}
238
/* No child processes */
239
break;
240
}
241
242
/* A child exited, find it in process_list */
243
while(proc != NULL and proc->pid != pid){
244
proc = proc->next;
245
}
246
if(proc == NULL){
247
/* Process not found in process list */
248
continue;
249
}
250
proc->status = status;
251
proc->completed = true;
252
}
253
}
254
255
/* Prints out a password to stdout */
256
static bool print_out_password(const char *buffer, size_t length){
257
ssize_t ret;
258
for(size_t written = 0; written < length; written += (size_t)ret){
259
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
260
length - written));
261
if(ret < 0){
262
return false;
263
}
264
}
265
return true;
266
}
267
268
/* Removes and free a plugin from the plugin list */
269
static void free_plugin(plugin *plugin_node){
270
271
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
272
free(*arg);
273
}
274
free(plugin_node->argv);
275
for(char **env = plugin_node->environ; *env != NULL; env++){
276
free(*env);
277
}
278
free(plugin_node->environ);
279
free(plugin_node->buffer);
280
281
/* Removes the plugin from the singly-linked list */
282
if(plugin_node == plugin_list){
283
/* First one - simple */
284
plugin_list = plugin_list->next;
285
} else {
286
/* Second one or later */
287
for(plugin *p = plugin_list; p != NULL; p = p->next){
288
if(p->next == plugin_node){
289
p->next = plugin_node->next;
290
break;
291
}
292
}
293
}
294
295
free(plugin_node);
296
}
297
298
static void free_plugin_list(void){
299
while(plugin_list != NULL){
300
free_plugin(plugin_list);
301
}
302
}
28
303
29
304
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;
305
char *plugindir = NULL;
306
char *argfile = NULL;
307
FILE *conffp;
308
size_t d_name_len;
309
DIR *dir = NULL;
33
310
struct dirent *dirst;
34
311
struct stat st;
35
fd_set rfds_orig;
36
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
312
fd_set rfds_all;
313
int ret, numchars, maxfd = 0;
314
ssize_t sret;
315
intmax_t tmpmax;
316
uid_t uid = 65534;
317
gid_t gid = 65534;
318
bool debug = false;
319
int exitstatus = EXIT_SUCCESS;
320
struct sigaction old_sigchld_action;
321
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
322
.sa_flags = SA_NOCLDSTOP };
323
char **custom_argv = NULL;
324
int custom_argc = 0;
325
326
/* Establish a signal handler */
327
sigemptyset(&sigchld_action.sa_mask);
328
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
329
if(ret == -1){
330
perror("sigaddset");
331
exitstatus = EXIT_FAILURE;
332
goto fallback;
333
}
334
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
335
if(ret == -1){
336
perror("sigaction");
337
exitstatus = EXIT_FAILURE;
338
goto fallback;
339
}
340
341
/* The options we understand. */
342
struct argp_option options[] = {
343
{ .name = "global-options", .key = 'g',
344
.arg = "OPTION[,OPTION[,...]]",
345
.doc = "Options passed to all plugins" },
346
{ .name = "global-env", .key = 'G',
347
.arg = "VAR=value",
348
.doc = "Environment variable passed to all plugins" },
349
{ .name = "options-for", .key = 'o',
350
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
351
.doc = "Options passed only to specified plugin" },
352
{ .name = "env-for", .key = 'E',
353
.arg = "PLUGIN:ENV=value",
354
.doc = "Environment variable passed to specified plugin" },
355
{ .name = "disable", .key = 'd',
356
.arg = "PLUGIN",
357
.doc = "Disable a specific plugin", .group = 1 },
358
{ .name = "enable", .key = 'e',
359
.arg = "PLUGIN",
360
.doc = "Enable a specific plugin", .group = 1 },
361
{ .name = "plugin-dir", .key = 128,
362
.arg = "DIRECTORY",
363
.doc = "Specify a different plugin directory", .group = 2 },
364
{ .name = "config-file", .key = 129,
365
.arg = "FILE",
366
.doc = "Specify a different configuration file", .group = 2 },
367
{ .name = "userid", .key = 130,
368
.arg = "ID", .flags = 0,
369
.doc = "User ID the plugins will run as", .group = 3 },
370
{ .name = "groupid", .key = 131,
371
.arg = "ID", .flags = 0,
372
.doc = "Group ID the plugins will run as", .group = 3 },
373
{ .name = "debug", .key = 132,
374
.doc = "Debug mode", .group = 4 },
375
{ .name = NULL }
376
};
377
378
error_t parse_opt(int key, char *arg, __attribute__((unused))
379
struct argp_state *state) {
380
switch(key) {
381
case 'g': /* --global-options */
382
if(arg != NULL){
383
char *p;
384
while((p = strsep(&arg, ",")) != NULL){
385
if(p[0] == '\0'){
386
continue;
387
}
388
if(not add_argument(getplugin(NULL), p)){
389
perror("add_argument");
390
return ARGP_ERR_UNKNOWN;
391
}
392
}
393
}
394
break;
395
case 'G': /* --global-env */
396
if(arg == NULL){
397
break;
398
}
399
if(not add_environment(getplugin(NULL), arg, true)){
400
perror("add_environment");
401
}
402
break;
403
case 'o': /* --options-for */
404
if(arg != NULL){
405
char *p_name = strsep(&arg, ":");
406
if(p_name[0] == '\0' or arg == NULL){
407
break;
408
}
409
char *opt = strsep(&arg, ":");
410
if(opt[0] == '\0' or opt == NULL){
411
break;
412
}
413
char *p;
414
while((p = strsep(&opt, ",")) != NULL){
415
if(p[0] == '\0'){
416
continue;
417
}
418
if(not add_argument(getplugin(p_name), p)){
419
perror("add_argument");
420
return ARGP_ERR_UNKNOWN;
421
}
422
}
423
}
424
break;
425
case 'E': /* --env-for */
426
if(arg == NULL){
427
break;
428
}
429
{
430
char *envdef = strchr(arg, ':');
431
if(envdef == NULL){
432
break;
433
}
434
*envdef = '\0';
435
if(not add_environment(getplugin(arg), envdef+1, true)){
436
perror("add_environment");
437
}
438
}
439
break;
440
case 'd': /* --disable */
441
if(arg != NULL){
442
plugin *p = getplugin(arg);
443
if(p == NULL){
444
return ARGP_ERR_UNKNOWN;
445
}
446
p->disabled = true;
447
}
448
break;
449
case 'e': /* --enable */
450
if(arg != NULL){
451
plugin *p = getplugin(arg);
452
if(p == NULL){
453
return ARGP_ERR_UNKNOWN;
454
}
455
p->disabled = false;
456
}
457
break;
458
case 128: /* --plugin-dir */
459
free(plugindir);
460
plugindir = strdup(arg);
461
if(plugindir == NULL){
462
perror("strdup");
463
}
464
break;
465
case 129: /* --config-file */
466
/* This is already done by parse_opt_config_file() */
467
break;
468
case 130: /* --userid */
469
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
470
if(ret < 1 or tmpmax != (uid_t)tmpmax
471
or arg[numchars] != '\0'){
472
fprintf(stderr, "Bad user ID number: \"%s\", using %"
473
PRIdMAX "\n", arg, (intmax_t)uid);
474
} else {
475
uid = (uid_t)tmpmax;
476
}
477
break;
478
case 131: /* --groupid */
479
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
480
if(ret < 1 or tmpmax != (gid_t)tmpmax
481
or arg[numchars] != '\0'){
482
fprintf(stderr, "Bad group ID number: \"%s\", using %"
483
PRIdMAX "\n", arg, (intmax_t)gid);
484
} else {
485
gid = (gid_t)tmpmax;
486
}
487
break;
488
case 132: /* --debug */
489
debug = true;
490
break;
491
/*
492
* When adding more options before this line, remember to also add a
493
* "case" to the "parse_opt_config_file" function below.
494
*/
495
case ARGP_KEY_ARG:
496
/* Cryptsetup always passes an argument, which is an empty
497
string if "none" was specified in /etc/crypttab. So if
498
argument was empty, we ignore it silently. */
499
if(arg[0] != '\0'){
500
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
501
}
502
break;
503
case ARGP_KEY_END:
504
break;
505
default:
506
return ARGP_ERR_UNKNOWN;
507
}
508
return 0;
509
}
510
511
/* This option parser is the same as parse_opt() above, except it
512
ignores everything but the --config-file option. */
513
error_t parse_opt_config_file(int key, char *arg,
514
__attribute__((unused))
515
struct argp_state *state) {
516
switch(key) {
517
case 'g': /* --global-options */
518
case 'G': /* --global-env */
519
case 'o': /* --options-for */
520
case 'E': /* --env-for */
521
case 'd': /* --disable */
522
case 'e': /* --enable */
523
case 128: /* --plugin-dir */
524
break;
525
case 129: /* --config-file */
526
free(argfile);
527
argfile = strdup(arg);
528
if(argfile == NULL){
529
perror("strdup");
530
}
531
break;
532
case 130: /* --userid */
533
case 131: /* --groupid */
534
case 132: /* --debug */
535
case ARGP_KEY_ARG:
536
case ARGP_KEY_END:
537
break;
538
default:
539
return ARGP_ERR_UNKNOWN;
540
}
541
return 0;
542
}
543
544
struct argp argp = { .options = options,
545
.parser = parse_opt_config_file,
546
.args_doc = "",
547
.doc = "Mandos plugin runner -- Run plugins" };
548
549
/* Parse using parse_opt_config_file() in order to get the custom
550
config file location, if any. */
551
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
552
if(ret == ARGP_ERR_UNKNOWN){
553
fprintf(stderr, "Unknown error while parsing arguments\n");
554
exitstatus = EXIT_FAILURE;
555
goto fallback;
556
}
557
558
/* Reset to the normal argument parser */
559
argp.parser = parse_opt;
560
561
/* Open the configfile if available */
562
if(argfile == NULL){
563
conffp = fopen(AFILE, "r");
564
} else {
565
conffp = fopen(argfile, "r");
566
}
567
if(conffp != NULL){
568
char *org_line = NULL;
569
char *p, *arg, *new_arg, *line;
570
size_t size = 0;
571
const char whitespace_delims[] = " \r\t\f\v\n";
572
const char comment_delim[] = "#";
573
574
custom_argc = 1;
575
custom_argv = malloc(sizeof(char*) * 2);
576
if(custom_argv == NULL){
577
perror("malloc");
578
exitstatus = EXIT_FAILURE;
579
goto fallback;
580
}
581
custom_argv[0] = argv[0];
582
custom_argv[1] = NULL;
583
584
/* for each line in the config file, strip whitespace and ignore
585
commented text */
586
while(true){
587
sret = getline(&org_line, &size, conffp);
588
if(sret == -1){
589
break;
590
}
591
592
line = org_line;
593
arg = strsep(&line, comment_delim);
594
while((p = strsep(&arg, whitespace_delims)) != NULL){
595
if(p[0] == '\0'){
596
continue;
597
}
598
new_arg = strdup(p);
599
if(new_arg == NULL){
600
perror("strdup");
601
exitstatus = EXIT_FAILURE;
602
free(org_line);
603
goto fallback;
604
}
605
606
custom_argc += 1;
607
custom_argv = realloc(custom_argv, sizeof(char *)
608
* ((unsigned int) custom_argc + 1));
609
if(custom_argv == NULL){
610
perror("realloc");
611
exitstatus = EXIT_FAILURE;
612
free(org_line);
613
goto fallback;
614
}
615
custom_argv[custom_argc-1] = new_arg;
616
custom_argv[custom_argc] = NULL;
617
}
618
}
619
free(org_line);
620
} else {
621
/* Check for harmful errors and go to fallback. Other errors might
622
not affect opening plugins */
623
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
624
perror("fopen");
625
exitstatus = EXIT_FAILURE;
626
goto fallback;
627
}
628
}
629
/* If there was any arguments from configuration file,
630
pass them to parser as command arguments */
631
if(custom_argv != NULL){
632
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
633
0, NULL);
634
if(ret == ARGP_ERR_UNKNOWN){
635
fprintf(stderr, "Unknown error while parsing arguments\n");
636
exitstatus = EXIT_FAILURE;
637
goto fallback;
638
}
639
}
640
641
/* Parse actual command line arguments, to let them override the
642
config file */
643
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
644
if(ret == ARGP_ERR_UNKNOWN){
645
fprintf(stderr, "Unknown error while parsing arguments\n");
646
exitstatus = EXIT_FAILURE;
647
goto fallback;
648
}
649
650
if(debug){
651
for(plugin *p = plugin_list; p != NULL; p=p->next){
652
fprintf(stderr, "Plugin: %s has %d arguments\n",
653
p->name ? p->name : "Global", p->argc - 1);
654
for(char **a = p->argv; *a != NULL; a++){
655
fprintf(stderr, "\tArg: %s\n", *a);
656
}
657
fprintf(stderr, "...and %d environment variables\n", p->envc);
658
for(char **a = p->environ; *a != NULL; a++){
659
fprintf(stderr, "\t%s\n", *a);
660
}
661
}
662
}
663
664
/* Strip permissions down to nobody */
665
ret = setuid(uid);
666
if(ret == -1){
667
perror("setuid");
668
}
669
setgid(gid);
670
if(ret == -1){
671
perror("setgid");
672
}
673
674
if(plugindir == NULL){
675
dir = opendir(PDIR);
676
} else {
677
dir = opendir(plugindir);
678
}
679
41
680
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
681
perror("Could not open plugin dir");
682
exitstatus = EXIT_FAILURE;
683
goto fallback;
684
}
685
686
/* Set the FD_CLOEXEC flag on the directory, if possible */
687
{
688
int dir_fd = dirfd(dir);
689
if(dir_fd >= 0){
690
ret = set_cloexec_flag(dir_fd);
691
if(ret < 0){
692
perror("set_cloexec_flag");
693
exitstatus = EXIT_FAILURE;
694
goto fallback;
695
}
696
}
697
}
698
699
FD_ZERO(&rfds_all);
700
701
/* Read and execute any executable in the plugin directory*/
48
702
while(true){
49
703
dirst = readdir(dir);
50
704
51
// All directory entries have been processed
705
/* All directory entries have been processed */
52
706
if(dirst == NULL){
707
if(errno == EBADF){
708
perror("readdir");
709
exitstatus = EXIT_FAILURE;
710
goto fallback;
711
}
53
712
break;
54
713
}
55
714
56
715
d_name_len = strlen(dirst->d_name);
57
716
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 */
717
/* Ignore dotfiles, backup files and other junk */
718
{
719
bool bad_name = false;
720
721
const char const *bad_prefixes[] = { ".", "#", NULL };
722
723
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
724
".dpkg-old",
725
".dpkg-bak",
726
".dpkg-divert", NULL };
727
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
728
size_t pre_len = strlen(*pre);
729
if((d_name_len >= pre_len)
730
and strncmp((dirst->d_name), *pre, pre_len) == 0){
731
if(debug){
732
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
733
" with bad prefix %s\n", dirst->d_name, *pre);
734
}
735
bad_name = true;
736
break;
737
}
738
}
739
if(bad_name){
740
continue;
741
}
742
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
743
size_t suf_len = strlen(*suf);
744
if((d_name_len >= suf_len)
745
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
746
== 0)){
747
if(debug){
748
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
749
" with bad suffix %s\n", dirst->d_name, *suf);
750
}
751
bad_name = true;
752
break;
753
}
754
}
755
756
if(bad_name){
757
continue;
758
}
759
}
760
761
char *filename;
762
if(plugindir == NULL){
763
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
764
} else {
765
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
766
}
767
if(ret < 0){
768
perror("asprintf");
769
continue;
770
}
771
772
ret = stat(filename, &st);
773
if(ret == -1){
774
perror("stat");
775
free(filename);
776
continue;
777
}
778
779
/* Ignore non-executable files */
780
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
781
if(debug){
782
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
783
" with bad type or mode\n", filename);
784
}
785
free(filename);
786
continue;
787
}
788
789
plugin *p = getplugin(dirst->d_name);
790
if(p == NULL){
791
perror("getplugin");
792
free(filename);
793
continue;
794
}
795
if(p->disabled){
796
if(debug){
797
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
798
dirst->d_name);
799
}
800
free(filename);
801
continue;
802
}
803
{
804
/* Add global arguments to argument list for this plugin */
805
plugin *g = getplugin(NULL);
806
if(g != NULL){
807
for(char **a = g->argv + 1; *a != NULL; a++){
808
if(not add_argument(p, *a)){
809
perror("add_argument");
810
}
811
}
812
/* Add global environment variables */
813
for(char **e = g->environ; *e != NULL; e++){
814
if(not add_environment(p, *e, false)){
815
perror("add_environment");
816
}
817
}
818
}
819
}
820
/* If this plugin has any environment variables, we will call
821
using execve and need to duplicate the environment from this
822
process, too. */
823
if(p->environ[0] != NULL){
824
for(char **e = environ; *e != NULL; e++){
825
if(not add_environment(p, *e, false)){
826
perror("add_environment");
827
}
828
}
829
}
830
831
int pipefd[2];
832
ret = pipe(pipefd);
833
if(ret == -1){
834
perror("pipe");
835
exitstatus = EXIT_FAILURE;
836
goto fallback;
837
}
838
/* Ask OS to automatic close the pipe on exec */
839
ret = set_cloexec_flag(pipefd[0]);
840
if(ret < 0){
841
perror("set_cloexec_flag");
842
exitstatus = EXIT_FAILURE;
843
goto fallback;
844
}
845
ret = set_cloexec_flag(pipefd[1]);
846
if(ret < 0){
847
perror("set_cloexec_flag");
848
exitstatus = EXIT_FAILURE;
849
goto fallback;
850
}
851
/* Block SIGCHLD until process is safely in process list */
852
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
853
if(ret < 0){
854
perror("sigprocmask");
855
exitstatus = EXIT_FAILURE;
856
goto fallback;
857
}
858
/* Starting a new process to be watched */
859
pid_t pid = fork();
860
if(pid == -1){
861
perror("fork");
862
exitstatus = EXIT_FAILURE;
863
goto fallback;
864
}
865
if(pid == 0){
866
/* this is the child process */
867
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
868
if(ret < 0){
869
perror("sigaction");
870
_exit(EXIT_FAILURE);
871
}
872
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
873
if(ret < 0){
874
perror("sigprocmask");
875
_exit(EXIT_FAILURE);
876
}
877
878
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
879
if(ret == -1){
880
perror("dup2");
881
_exit(EXIT_FAILURE);
882
}
883
884
if(dirfd(dir) < 0){
885
/* If dir has no file descriptor, we could not set FD_CLOEXEC
886
above and must now close it manually here. */
79
887
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;
888
}
889
if(p->environ[0] == NULL){
890
if(execv(filename, p->argv) < 0){
891
perror("execv");
892
_exit(EXIT_FAILURE);
893
}
894
} else {
895
if(execve(filename, p->argv, p->environ) < 0){
896
perror("execve");
897
_exit(EXIT_FAILURE);
898
}
899
}
900
/* no return */
901
}
902
/* Parent process */
903
close(pipefd[1]); /* Close unused write end of pipe */
904
free(filename);
905
plugin *new_plugin = getplugin(dirst->d_name);
906
if(new_plugin == NULL){
907
perror("getplugin");
908
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
909
if(ret < 0){
910
perror("sigprocmask");
911
}
912
exitstatus = EXIT_FAILURE;
913
goto fallback;
914
}
915
916
new_plugin->pid = pid;
917
new_plugin->fd = pipefd[0];
918
919
/* Unblock SIGCHLD so signal handler can be run if this process
920
has already completed */
921
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
922
if(ret < 0){
923
perror("sigprocmask");
924
exitstatus = EXIT_FAILURE;
925
goto fallback;
926
}
927
928
FD_SET(new_plugin->fd, &rfds_all);
929
930
if(maxfd < new_plugin->fd){
931
maxfd = new_plugin->fd;
114
932
}
115
933
}
116
934
117
935
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
}
936
dir = NULL;
937
938
for(plugin *p = plugin_list; p != NULL; p = p->next){
939
if(p->pid != 0){
178
940
break;
179
941
}
180
}
181
return EXIT_SUCCESS;
942
if(p->next == NULL){
943
fprintf(stderr, "No plugin processes started. Incorrect plugin"
944
" directory?\n");
945
free_plugin_list();
946
}
947
}
948
949
/* Main loop while running plugins exist */
950
while(plugin_list){
951
fd_set rfds = rfds_all;
952
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
953
if(select_ret == -1){
954
perror("select");
955
exitstatus = EXIT_FAILURE;
956
goto fallback;
957
}
958
/* OK, now either a process completed, or something can be read
959
from one of them */
960
for(plugin *proc = plugin_list; proc != NULL;){
961
/* Is this process completely done? */
962
if(proc->eof and proc->completed){
963
/* Only accept the plugin output if it exited cleanly */
964
if(not WIFEXITED(proc->status)
965
or WEXITSTATUS(proc->status) != 0){
966
/* Bad exit by plugin */
967
968
if(debug){
969
if(WIFEXITED(proc->status)){
970
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
971
" %d\n", (intmax_t) (proc->pid),
972
WEXITSTATUS(proc->status));
973
} else if(WIFSIGNALED(proc->status)) {
974
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
975
" %d\n", (intmax_t) (proc->pid),
976
WTERMSIG(proc->status));
977
} else if(WCOREDUMP(proc->status)){
978
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
979
(intmax_t) (proc->pid));
980
}
981
}
982
983
/* Remove the plugin */
984
FD_CLR(proc->fd, &rfds_all);
985
986
/* Block signal while modifying process_list */
987
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
988
if(ret < 0){
989
perror("sigprocmask");
990
exitstatus = EXIT_FAILURE;
991
goto fallback;
992
}
993
994
plugin *next_plugin = proc->next;
995
free_plugin(proc);
996
proc = next_plugin;
997
998
/* We are done modifying process list, so unblock signal */
999
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1000
NULL);
1001
if(ret < 0){
1002
perror("sigprocmask");
1003
exitstatus = EXIT_FAILURE;
1004
goto fallback;
1005
}
1006
1007
if(plugin_list == NULL){
1008
break;
1009
}
1010
1011
continue;
1012
}
1013
1014
/* This process exited nicely, so print its buffer */
1015
1016
bool bret = print_out_password(proc->buffer,
1017
proc->buffer_length);
1018
if(not bret){
1019
perror("print_out_password");
1020
exitstatus = EXIT_FAILURE;
1021
}
1022
goto fallback;
1023
}
1024
1025
/* This process has not completed. Does it have any output? */
1026
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1027
/* This process had nothing to say at this time */
1028
proc = proc->next;
1029
continue;
1030
}
1031
/* Before reading, make the process' data buffer large enough */
1032
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1033
proc->buffer = realloc(proc->buffer, proc->buffer_size
1034
+ (size_t) BUFFER_SIZE);
1035
if(proc->buffer == NULL){
1036
perror("malloc");
1037
exitstatus = EXIT_FAILURE;
1038
goto fallback;
1039
}
1040
proc->buffer_size += BUFFER_SIZE;
1041
}
1042
/* Read from the process */
1043
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1044
BUFFER_SIZE);
1045
if(sret < 0){
1046
/* Read error from this process; ignore the error */
1047
proc = proc->next;
1048
continue;
1049
}
1050
if(sret == 0){
1051
/* got EOF */
1052
proc->eof = true;
1053
} else {
1054
proc->buffer_length += (size_t) sret;
1055
}
1056
}
1057
}
1058
1059
1060
fallback:
1061
1062
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1063
/* Fallback if all plugins failed, none are found or an error
1064
occured */
1065
bool bret;
1066
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1067
char *passwordbuffer = getpass("Password: ");
1068
size_t len = strlen(passwordbuffer);
1069
/* Strip trailing newline */
1070
if(len > 0 and passwordbuffer[len-1] == '\n'){
1071
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1072
len--;
1073
}
1074
bret = print_out_password(passwordbuffer, len);
1075
if(not bret){
1076
perror("print_out_password");
1077
exitstatus = EXIT_FAILURE;
1078
}
1079
}
1080
1081
/* Restore old signal handler */
1082
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1083
if(ret == -1){
1084
perror("sigaction");
1085
exitstatus = EXIT_FAILURE;
1086
}
1087
1088
if(custom_argv != NULL){
1089
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1090
free(*arg);
1091
}
1092
free(custom_argv);
1093
}
1094
1095
if(dir != NULL){
1096
closedir(dir);
1097
}
1098
1099
/* Kill the processes */
1100
for(plugin *p = plugin_list; p != NULL; p = p->next){
1101
if(p->pid != 0){
1102
close(p->fd);
1103
ret = kill(p->pid, SIGTERM);
1104
if(ret == -1 and errno != ESRCH){
1105
/* Set-uid proccesses might not get closed */
1106
perror("kill");
1107
}
1108
}
1109
}
1110
1111
/* Wait for any remaining child processes to terminate */
1112
do{
1113
ret = wait(NULL);
1114
} while(ret >= 0);
1115
if(errno != ECHILD){
1116
perror("wait");
1117
}
1118
1119
free_plugin_list();
1120
1121
free(plugindir);
1122
free(argfile);
1123
1124
return exitstatus;
182
1125
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0