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 342
- compare with another revision
- download diff
- download tarball
- view history from revision 342
- Committer: Teddy Hogeborn
- Date: 2009-04-17 08:26:17 UTC
- Revision ID: teddy@fukt.bsnet.se-20090417082617-eltetak5lzjyz55o
* initramfs-tools-hook: Bug fix: Add "--userid" and "--groupid" to
start of "plugin-runner.conf" file instead of
appending, to allow any preexisting options to
override.
* plugin-runner.conf: Improved wording.
start of "plugin-runner.conf" file instead of
appending, to allow any preexisting options to
override.
* plugin-runner.conf: Improved wording.
- 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(), sig_atomic_t
66
*/
67
#include <errno.h> /* errno, EBADF */
68
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
69
70
#define BUFFER_SIZE 256
71
72
#define PDIR "/lib/mandos/plugins.d"
73
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
74
75
const char *argp_program_version = "plugin-runner " VERSION;
76
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
77
78
typedef struct plugin{
79
char *name; /* can be NULL or any plugin name */
80
char **argv;
81
int argc;
82
char **environ;
83
int envc;
84
bool disabled;
85
86
/* Variables used for running processes*/
19
87
pid_t pid;
20
88
int fd;
21
89
char *buffer;
22
int buffer_size;
23
int buffer_length;
24
struct process *next;
25
} process;
26
27
#define BUFFER_SIZE 256
90
size_t buffer_size;
91
size_t buffer_length;
92
bool eof;
93
volatile sig_atomic_t completed;
94
int status;
95
struct plugin *next;
96
} plugin;
97
98
static plugin *plugin_list = NULL;
99
100
/* Gets an existing plugin based on name,
101
or if none is found, creates a new one */
102
static plugin *getplugin(char *name){
103
/* Check for exiting plugin with that name */
104
for(plugin *p = plugin_list; p != NULL; p = p->next){
105
if((p->name == name)
106
or (p->name and name and (strcmp(p->name, name) == 0))){
107
return p;
108
}
109
}
110
/* Create a new plugin */
111
plugin *new_plugin = malloc(sizeof(plugin));
112
if(new_plugin == NULL){
113
return NULL;
114
}
115
char *copy_name = NULL;
116
if(name != NULL){
117
copy_name = strdup(name);
118
if(copy_name == NULL){
119
free(new_plugin);
120
return NULL;
121
}
122
}
123
124
*new_plugin = (plugin){ .name = copy_name,
125
.argc = 1,
126
.disabled = false,
127
.next = plugin_list };
128
129
new_plugin->argv = malloc(sizeof(char *) * 2);
130
if(new_plugin->argv == NULL){
131
free(copy_name);
132
free(new_plugin);
133
return NULL;
134
}
135
new_plugin->argv[0] = copy_name;
136
new_plugin->argv[1] = NULL;
137
138
new_plugin->environ = malloc(sizeof(char *));
139
if(new_plugin->environ == NULL){
140
free(copy_name);
141
free(new_plugin->argv);
142
free(new_plugin);
143
return NULL;
144
}
145
new_plugin->environ[0] = NULL;
146
147
/* Append the new plugin to the list */
148
plugin_list = new_plugin;
149
return new_plugin;
150
}
151
152
/* Helper function for add_argument and add_environment */
153
static bool add_to_char_array(const char *new, char ***array,
154
int *len){
155
/* Resize the pointed-to array to hold one more pointer */
156
*array = realloc(*array, sizeof(char *)
157
* (size_t) ((*len) + 2));
158
/* Malloc check */
159
if(*array == NULL){
160
return false;
161
}
162
/* Make a copy of the new string */
163
char *copy = strdup(new);
164
if(copy == NULL){
165
return false;
166
}
167
/* Insert the copy */
168
(*array)[*len] = copy;
169
(*len)++;
170
/* Add a new terminating NULL pointer to the last element */
171
(*array)[*len] = NULL;
172
return true;
173
}
174
175
/* Add to a plugin's argument vector */
176
static bool add_argument(plugin *p, const char *arg){
177
if(p == NULL){
178
return false;
179
}
180
return add_to_char_array(arg, &(p->argv), &(p->argc));
181
}
182
183
/* Add to a plugin's environment */
184
static bool add_environment(plugin *p, const char *def, bool replace){
185
if(p == NULL){
186
return false;
187
}
188
/* namelen = length of name of environment variable */
189
size_t namelen = (size_t)(strchrnul(def, '=') - def);
190
/* Search for this environment variable */
191
for(char **e = p->environ; *e != NULL; e++){
192
if(strncmp(*e, def, namelen + 1) == 0){
193
/* It already exists */
194
if(replace){
195
char *new = realloc(*e, strlen(def) + 1);
196
if(new == NULL){
197
return false;
198
}
199
*e = new;
200
strcpy(*e, def);
201
}
202
return true;
203
}
204
}
205
return add_to_char_array(def, &(p->environ), &(p->envc));
206
}
207
208
/*
209
* Based on the example in the GNU LibC manual chapter 13.13 "File
210
* Descriptor Flags".
211
* *Note File Descriptor Flags:(libc)Descriptor Flags.
212
*/
213
static int set_cloexec_flag(int fd){
214
int ret = fcntl(fd, F_GETFD, 0);
215
/* If reading the flags failed, return error indication now. */
216
if(ret < 0){
217
return ret;
218
}
219
/* Store modified flag word in the descriptor. */
220
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
221
}
222
223
224
/* Mark processes as completed when they exit, and save their exit
225
status. */
226
static void handle_sigchld(__attribute__((unused)) int sig){
227
int old_errno = errno;
228
while(true){
229
plugin *proc = plugin_list;
230
int status;
231
pid_t pid = waitpid(-1, &status, WNOHANG);
232
if(pid == 0){
233
/* Only still running child processes */
234
break;
235
}
236
if(pid == -1){
237
if(errno == ECHILD){
238
/* No child processes */
239
break;
240
}
241
perror("waitpid");
242
}
243
244
/* A child exited, find it in process_list */
245
while(proc != NULL and proc->pid != pid){
246
proc = proc->next;
247
}
248
if(proc == NULL){
249
/* Process not found in process list */
250
continue;
251
}
252
proc->status = status;
253
proc->completed = 1;
254
}
255
errno = old_errno;
256
}
257
258
/* Prints out a password to stdout */
259
static bool print_out_password(const char *buffer, size_t length){
260
ssize_t ret;
261
for(size_t written = 0; written < length; written += (size_t)ret){
262
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
263
length - written));
264
if(ret < 0){
265
return false;
266
}
267
}
268
return true;
269
}
270
271
/* Removes and free a plugin from the plugin list */
272
static void free_plugin(plugin *plugin_node){
273
274
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
275
free(*arg);
276
}
277
free(plugin_node->argv);
278
for(char **env = plugin_node->environ; *env != NULL; env++){
279
free(*env);
280
}
281
free(plugin_node->environ);
282
free(plugin_node->buffer);
283
284
/* Removes the plugin from the singly-linked list */
285
if(plugin_node == plugin_list){
286
/* First one - simple */
287
plugin_list = plugin_list->next;
288
} else {
289
/* Second one or later */
290
for(plugin *p = plugin_list; p != NULL; p = p->next){
291
if(p->next == plugin_node){
292
p->next = plugin_node->next;
293
break;
294
}
295
}
296
}
297
298
free(plugin_node);
299
}
300
301
static void free_plugin_list(void){
302
while(plugin_list != NULL){
303
free_plugin(plugin_list);
304
}
305
}
28
306
29
307
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;
308
char *plugindir = NULL;
309
char *argfile = NULL;
310
FILE *conffp;
311
size_t d_name_len;
312
DIR *dir = NULL;
33
313
struct dirent *dirst;
34
314
struct stat st;
35
fd_set rfds_orig;
315
fd_set rfds_all;
36
316
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
317
ssize_t sret;
318
intmax_t tmpmax;
319
uid_t uid = 65534;
320
gid_t gid = 65534;
321
bool debug = false;
322
int exitstatus = EXIT_SUCCESS;
323
struct sigaction old_sigchld_action;
324
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
325
.sa_flags = SA_NOCLDSTOP };
326
char **custom_argv = NULL;
327
int custom_argc = 0;
328
329
/* Establish a signal handler */
330
sigemptyset(&sigchld_action.sa_mask);
331
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
332
if(ret == -1){
333
perror("sigaddset");
334
exitstatus = EXIT_FAILURE;
335
goto fallback;
336
}
337
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
338
if(ret == -1){
339
perror("sigaction");
340
exitstatus = EXIT_FAILURE;
341
goto fallback;
342
}
343
344
/* The options we understand. */
345
struct argp_option options[] = {
346
{ .name = "global-options", .key = 'g',
347
.arg = "OPTION[,OPTION[,...]]",
348
.doc = "Options passed to all plugins" },
349
{ .name = "global-env", .key = 'G',
350
.arg = "VAR=value",
351
.doc = "Environment variable passed to all plugins" },
352
{ .name = "options-for", .key = 'o',
353
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
354
.doc = "Options passed only to specified plugin" },
355
{ .name = "env-for", .key = 'E',
356
.arg = "PLUGIN:ENV=value",
357
.doc = "Environment variable passed to specified plugin" },
358
{ .name = "disable", .key = 'd',
359
.arg = "PLUGIN",
360
.doc = "Disable a specific plugin", .group = 1 },
361
{ .name = "enable", .key = 'e',
362
.arg = "PLUGIN",
363
.doc = "Enable a specific plugin", .group = 1 },
364
{ .name = "plugin-dir", .key = 128,
365
.arg = "DIRECTORY",
366
.doc = "Specify a different plugin directory", .group = 2 },
367
{ .name = "config-file", .key = 129,
368
.arg = "FILE",
369
.doc = "Specify a different configuration file", .group = 2 },
370
{ .name = "userid", .key = 130,
371
.arg = "ID", .flags = 0,
372
.doc = "User ID the plugins will run as", .group = 3 },
373
{ .name = "groupid", .key = 131,
374
.arg = "ID", .flags = 0,
375
.doc = "Group ID the plugins will run as", .group = 3 },
376
{ .name = "debug", .key = 132,
377
.doc = "Debug mode", .group = 4 },
378
{ .name = NULL }
379
};
380
381
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
struct argp_state *state){
383
char *tmp;
384
switch(key){
385
case 'g': /* --global-options */
386
if(arg != NULL){
387
char *plugin_option;
388
while((plugin_option = strsep(&arg, ",")) != NULL){
389
if(plugin_option[0] == '\0'){
390
continue;
391
}
392
if(not add_argument(getplugin(NULL), plugin_option)){
393
perror("add_argument");
394
return ARGP_ERR_UNKNOWN;
395
}
396
}
397
}
398
break;
399
case 'G': /* --global-env */
400
if(arg == NULL){
401
break;
402
}
403
if(not add_environment(getplugin(NULL), arg, true)){
404
perror("add_environment");
405
}
406
break;
407
case 'o': /* --options-for */
408
if(arg != NULL){
409
char *plugin_name = strsep(&arg, ":");
410
if(plugin_name[0] == '\0'){
411
break;
412
}
413
char *plugin_option;
414
while((plugin_option = strsep(&arg, ",")) != NULL){
415
if(not add_argument(getplugin(plugin_name), plugin_option)){
416
perror("add_argument");
417
return ARGP_ERR_UNKNOWN;
418
}
419
}
420
}
421
break;
422
case 'E': /* --env-for */
423
if(arg == NULL){
424
break;
425
}
426
{
427
char *envdef = strchr(arg, ':');
428
if(envdef == NULL){
429
break;
430
}
431
*envdef = '\0';
432
if(not add_environment(getplugin(arg), envdef+1, true)){
433
perror("add_environment");
434
}
435
}
436
break;
437
case 'd': /* --disable */
438
if(arg != NULL){
439
plugin *p = getplugin(arg);
440
if(p == NULL){
441
return ARGP_ERR_UNKNOWN;
442
}
443
p->disabled = true;
444
}
445
break;
446
case 'e': /* --enable */
447
if(arg != NULL){
448
plugin *p = getplugin(arg);
449
if(p == NULL){
450
return ARGP_ERR_UNKNOWN;
451
}
452
p->disabled = false;
453
}
454
break;
455
case 128: /* --plugin-dir */
456
free(plugindir);
457
plugindir = strdup(arg);
458
if(plugindir == NULL){
459
perror("strdup");
460
}
461
break;
462
case 129: /* --config-file */
463
/* This is already done by parse_opt_config_file() */
464
break;
465
case 130: /* --userid */
466
errno = 0;
467
tmpmax = strtoimax(arg, &tmp, 10);
468
if(errno != 0 or tmp == arg or *tmp != '\0'
469
or tmpmax != (uid_t)tmpmax){
470
fprintf(stderr, "Bad user ID number: \"%s\", using %"
471
PRIdMAX "\n", arg, (intmax_t)uid);
472
} else {
473
uid = (uid_t)tmpmax;
474
}
475
break;
476
case 131: /* --groupid */
477
errno = 0;
478
tmpmax = strtoimax(arg, &tmp, 10);
479
if(errno != 0 or tmp == arg or *tmp != '\0'
480
or tmpmax != (gid_t)tmpmax){
481
fprintf(stderr, "Bad group ID number: \"%s\", using %"
482
PRIdMAX "\n", arg, (intmax_t)gid);
483
} else {
484
gid = (gid_t)tmpmax;
485
}
486
break;
487
case 132: /* --debug */
488
debug = true;
489
break;
490
/*
491
* When adding more options before this line, remember to also add a
492
* "case" to the "parse_opt_config_file" function below.
493
*/
494
case ARGP_KEY_ARG:
495
/* Cryptsetup always passes an argument, which is an empty
496
string if "none" was specified in /etc/crypttab. So if
497
argument was empty, we ignore it silently. */
498
if(arg[0] != '\0'){
499
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
500
}
501
break;
502
case ARGP_KEY_END:
503
break;
504
default:
505
return ARGP_ERR_UNKNOWN;
506
}
507
return 0;
508
}
509
510
/* This option parser is the same as parse_opt() above, except it
511
ignores everything but the --config-file option. */
512
error_t parse_opt_config_file(int key, char *arg,
513
__attribute__((unused))
514
struct argp_state *state){
515
switch(key){
516
case 'g': /* --global-options */
517
case 'G': /* --global-env */
518
case 'o': /* --options-for */
519
case 'E': /* --env-for */
520
case 'd': /* --disable */
521
case 'e': /* --enable */
522
case 128: /* --plugin-dir */
523
break;
524
case 129: /* --config-file */
525
free(argfile);
526
argfile = strdup(arg);
527
if(argfile == NULL){
528
perror("strdup");
529
}
530
break;
531
case 130: /* --userid */
532
case 131: /* --groupid */
533
case 132: /* --debug */
534
case ARGP_KEY_ARG:
535
case ARGP_KEY_END:
536
break;
537
default:
538
return ARGP_ERR_UNKNOWN;
539
}
540
return 0;
541
}
542
543
struct argp argp = { .options = options,
544
.parser = parse_opt_config_file,
545
.args_doc = "",
546
.doc = "Mandos plugin runner -- Run plugins" };
547
548
/* Parse using parse_opt_config_file() in order to get the custom
549
config file location, if any. */
550
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
551
if(ret == ARGP_ERR_UNKNOWN){
552
fprintf(stderr, "Unknown error while parsing arguments\n");
553
exitstatus = EXIT_FAILURE;
554
goto fallback;
555
}
556
557
/* Reset to the normal argument parser */
558
argp.parser = parse_opt;
559
560
/* Open the configfile if available */
561
if(argfile == NULL){
562
conffp = fopen(AFILE, "r");
563
} else {
564
conffp = fopen(argfile, "r");
565
}
566
if(conffp != NULL){
567
char *org_line = NULL;
568
char *p, *arg, *new_arg, *line;
569
size_t size = 0;
570
const char whitespace_delims[] = " \r\t\f\v\n";
571
const char comment_delim[] = "#";
572
573
custom_argc = 1;
574
custom_argv = malloc(sizeof(char*) * 2);
575
if(custom_argv == NULL){
576
perror("malloc");
577
exitstatus = EXIT_FAILURE;
578
goto fallback;
579
}
580
custom_argv[0] = argv[0];
581
custom_argv[1] = NULL;
582
583
/* for each line in the config file, strip whitespace and ignore
584
commented text */
585
while(true){
586
sret = getline(&org_line, &size, conffp);
587
if(sret == -1){
588
break;
589
}
590
591
line = org_line;
592
arg = strsep(&line, comment_delim);
593
while((p = strsep(&arg, whitespace_delims)) != NULL){
594
if(p[0] == '\0'){
595
continue;
596
}
597
new_arg = strdup(p);
598
if(new_arg == NULL){
599
perror("strdup");
600
exitstatus = EXIT_FAILURE;
601
free(org_line);
602
goto fallback;
603
}
604
605
custom_argc += 1;
606
custom_argv = realloc(custom_argv, sizeof(char *)
607
* ((unsigned int) custom_argc + 1));
608
if(custom_argv == NULL){
609
perror("realloc");
610
exitstatus = EXIT_FAILURE;
611
free(org_line);
612
goto fallback;
613
}
614
custom_argv[custom_argc-1] = new_arg;
615
custom_argv[custom_argc] = NULL;
616
}
617
}
618
free(org_line);
619
} else {
620
/* Check for harmful errors and go to fallback. Other errors might
621
not affect opening plugins */
622
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
623
perror("fopen");
624
exitstatus = EXIT_FAILURE;
625
goto fallback;
626
}
627
}
628
/* If there was any arguments from configuration file,
629
pass them to parser as command arguments */
630
if(custom_argv != NULL){
631
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
632
0, NULL);
633
if(ret == ARGP_ERR_UNKNOWN){
634
fprintf(stderr, "Unknown error while parsing arguments\n");
635
exitstatus = EXIT_FAILURE;
636
goto fallback;
637
}
638
}
639
640
/* Parse actual command line arguments, to let them override the
641
config file */
642
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
643
if(ret == ARGP_ERR_UNKNOWN){
644
fprintf(stderr, "Unknown error while parsing arguments\n");
645
exitstatus = EXIT_FAILURE;
646
goto fallback;
647
}
648
649
if(debug){
650
for(plugin *p = plugin_list; p != NULL; p=p->next){
651
fprintf(stderr, "Plugin: %s has %d arguments\n",
652
p->name ? p->name : "Global", p->argc - 1);
653
for(char **a = p->argv; *a != NULL; a++){
654
fprintf(stderr, "\tArg: %s\n", *a);
655
}
656
fprintf(stderr, "...and %d environment variables\n", p->envc);
657
for(char **a = p->environ; *a != NULL; a++){
658
fprintf(stderr, "\t%s\n", *a);
659
}
660
}
661
}
662
663
/* Strip permissions down to nobody */
664
setgid(gid);
665
if(ret == -1){
666
perror("setgid");
667
}
668
ret = setuid(uid);
669
if(ret == -1){
670
perror("setuid");
671
}
672
673
if(plugindir == NULL){
674
dir = opendir(PDIR);
675
} else {
676
dir = opendir(plugindir);
677
}
678
41
679
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
680
perror("Could not open plugin dir");
681
exitstatus = EXIT_FAILURE;
682
goto fallback;
683
}
684
685
/* Set the FD_CLOEXEC flag on the directory, if possible */
686
{
687
int dir_fd = dirfd(dir);
688
if(dir_fd >= 0){
689
ret = set_cloexec_flag(dir_fd);
690
if(ret < 0){
691
perror("set_cloexec_flag");
692
exitstatus = EXIT_FAILURE;
693
goto fallback;
694
}
695
}
696
}
697
698
FD_ZERO(&rfds_all);
699
700
/* Read and execute any executable in the plugin directory*/
48
701
while(true){
49
702
dirst = readdir(dir);
50
703
51
// All directory entries have been processed
704
/* All directory entries have been processed */
52
705
if(dirst == NULL){
706
if(errno == EBADF){
707
perror("readdir");
708
exitstatus = EXIT_FAILURE;
709
goto fallback;
710
}
53
711
break;
54
712
}
55
713
56
714
d_name_len = strlen(dirst->d_name);
57
715
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 + 1);
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 */
716
/* Ignore dotfiles, backup files and other junk */
717
{
718
bool bad_name = false;
719
720
const char const *bad_prefixes[] = { ".", "#", NULL };
721
722
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
723
".dpkg-old",
724
".dpkg-bak",
725
".dpkg-divert", NULL };
726
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
727
size_t pre_len = strlen(*pre);
728
if((d_name_len >= pre_len)
729
and strncmp((dirst->d_name), *pre, pre_len) == 0){
730
if(debug){
731
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
732
" with bad prefix %s\n", dirst->d_name, *pre);
733
}
734
bad_name = true;
735
break;
736
}
737
}
738
if(bad_name){
739
continue;
740
}
741
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
742
size_t suf_len = strlen(*suf);
743
if((d_name_len >= suf_len)
744
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
745
== 0)){
746
if(debug){
747
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
748
" with bad suffix %s\n", dirst->d_name, *suf);
749
}
750
bad_name = true;
751
break;
752
}
753
}
754
755
if(bad_name){
756
continue;
757
}
758
}
759
760
char *filename;
761
if(plugindir == NULL){
762
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
763
} else {
764
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
765
}
766
if(ret < 0){
767
perror("asprintf");
768
continue;
769
}
770
771
ret = stat(filename, &st);
772
if(ret == -1){
773
perror("stat");
774
free(filename);
775
continue;
776
}
777
778
/* Ignore non-executable files */
779
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
780
if(debug){
781
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
782
" with bad type or mode\n", filename);
783
}
784
free(filename);
785
continue;
786
}
787
788
plugin *p = getplugin(dirst->d_name);
789
if(p == NULL){
790
perror("getplugin");
791
free(filename);
792
continue;
793
}
794
if(p->disabled){
795
if(debug){
796
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
797
dirst->d_name);
798
}
799
free(filename);
800
continue;
801
}
802
{
803
/* Add global arguments to argument list for this plugin */
804
plugin *g = getplugin(NULL);
805
if(g != NULL){
806
for(char **a = g->argv + 1; *a != NULL; a++){
807
if(not add_argument(p, *a)){
808
perror("add_argument");
809
}
810
}
811
/* Add global environment variables */
812
for(char **e = g->environ; *e != NULL; e++){
813
if(not add_environment(p, *e, false)){
814
perror("add_environment");
815
}
816
}
817
}
818
}
819
/* If this plugin has any environment variables, we will call
820
using execve and need to duplicate the environment from this
821
process, too. */
822
if(p->environ[0] != NULL){
823
for(char **e = environ; *e != NULL; e++){
824
if(not add_environment(p, *e, false)){
825
perror("add_environment");
826
}
827
}
828
}
829
830
int pipefd[2];
831
ret = pipe(pipefd);
832
if(ret == -1){
833
perror("pipe");
834
exitstatus = EXIT_FAILURE;
835
goto fallback;
836
}
837
/* Ask OS to automatic close the pipe on exec */
838
ret = set_cloexec_flag(pipefd[0]);
839
if(ret < 0){
840
perror("set_cloexec_flag");
841
exitstatus = EXIT_FAILURE;
842
goto fallback;
843
}
844
ret = set_cloexec_flag(pipefd[1]);
845
if(ret < 0){
846
perror("set_cloexec_flag");
847
exitstatus = EXIT_FAILURE;
848
goto fallback;
849
}
850
/* Block SIGCHLD until process is safely in process list */
851
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
852
if(ret < 0){
853
perror("sigprocmask");
854
exitstatus = EXIT_FAILURE;
855
goto fallback;
856
}
857
/* Starting a new process to be watched */
858
pid_t pid = fork();
859
if(pid == -1){
860
perror("fork");
861
exitstatus = EXIT_FAILURE;
862
goto fallback;
863
}
864
if(pid == 0){
865
/* this is the child process */
866
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
867
if(ret < 0){
868
perror("sigaction");
869
_exit(EXIT_FAILURE);
870
}
871
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
872
if(ret < 0){
873
perror("sigprocmask");
874
_exit(EXIT_FAILURE);
875
}
876
877
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
878
if(ret == -1){
879
perror("dup2");
880
_exit(EXIT_FAILURE);
881
}
882
883
if(dirfd(dir) < 0){
884
/* If dir has no file descriptor, we could not set FD_CLOEXEC
885
above and must now close it manually here. */
79
886
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;
887
}
888
if(p->environ[0] == NULL){
889
if(execv(filename, p->argv) < 0){
890
perror("execv");
891
_exit(EXIT_FAILURE);
892
}
893
} else {
894
if(execve(filename, p->argv, p->environ) < 0){
895
perror("execve");
896
_exit(EXIT_FAILURE);
897
}
898
}
899
/* no return */
900
}
901
/* Parent process */
902
close(pipefd[1]); /* Close unused write end of pipe */
903
free(filename);
904
plugin *new_plugin = getplugin(dirst->d_name);
905
if(new_plugin == NULL){
906
perror("getplugin");
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
908
if(ret < 0){
909
perror("sigprocmask");
910
}
911
exitstatus = EXIT_FAILURE;
912
goto fallback;
913
}
914
915
new_plugin->pid = pid;
916
new_plugin->fd = pipefd[0];
917
918
/* Unblock SIGCHLD so signal handler can be run if this process
919
has already completed */
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
921
if(ret < 0){
922
perror("sigprocmask");
923
exitstatus = EXIT_FAILURE;
924
goto fallback;
925
}
926
927
FD_SET(new_plugin->fd, &rfds_all);
928
929
if(maxfd < new_plugin->fd){
930
maxfd = new_plugin->fd;
114
931
}
115
932
}
116
933
117
934
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
}
935
dir = NULL;
936
free_plugin(getplugin(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->completed and proc->eof){
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 %s [%" PRIdMAX "] exited with"
971
" status %d\n", proc->name,
972
(intmax_t) (proc->pid),
973
WEXITSTATUS(proc->status));
974
} else if(WIFSIGNALED(proc->status)){
975
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
976
" signal %d\n", proc->name,
977
(intmax_t) (proc->pid),
978
WTERMSIG(proc->status));
979
} else if(WCOREDUMP(proc->status)){
980
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
981
" core\n", proc->name, (intmax_t) (proc->pid));
982
}
983
}
984
985
/* Remove the plugin */
986
FD_CLR(proc->fd, &rfds_all);
987
988
/* Block signal while modifying process_list */
989
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
990
if(ret < 0){
991
perror("sigprocmask");
992
exitstatus = EXIT_FAILURE;
993
goto fallback;
994
}
995
996
plugin *next_plugin = proc->next;
997
free_plugin(proc);
998
proc = next_plugin;
999
1000
/* We are done modifying process list, so unblock signal */
1001
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1002
NULL);
1003
if(ret < 0){
1004
perror("sigprocmask");
1005
exitstatus = EXIT_FAILURE;
1006
goto fallback;
1007
}
1008
1009
if(plugin_list == NULL){
1010
break;
1011
}
1012
1013
continue;
1014
}
1015
1016
/* This process exited nicely, so print its buffer */
1017
1018
bool bret = print_out_password(proc->buffer,
1019
proc->buffer_length);
1020
if(not bret){
1021
perror("print_out_password");
1022
exitstatus = EXIT_FAILURE;
1023
}
1024
goto fallback;
1025
}
1026
1027
/* This process has not completed. Does it have any output? */
1028
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1029
/* This process had nothing to say at this time */
1030
proc = proc->next;
1031
continue;
1032
}
1033
/* Before reading, make the process' data buffer large enough */
1034
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1035
proc->buffer = realloc(proc->buffer, proc->buffer_size
1036
+ (size_t) BUFFER_SIZE);
1037
if(proc->buffer == NULL){
1038
perror("malloc");
1039
exitstatus = EXIT_FAILURE;
1040
goto fallback;
1041
}
1042
proc->buffer_size += BUFFER_SIZE;
1043
}
1044
/* Read from the process */
1045
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1046
BUFFER_SIZE);
1047
if(sret < 0){
1048
/* Read error from this process; ignore the error */
1049
proc = proc->next;
1050
continue;
1051
}
1052
if(sret == 0){
1053
/* got EOF */
1054
proc->eof = true;
1055
} else {
1056
proc->buffer_length += (size_t) sret;
1057
}
1058
}
1059
}
1060
1061
1062
fallback:
1063
1064
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1065
/* Fallback if all plugins failed, none are found or an error
1066
occured */
1067
bool bret;
1068
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1069
char *passwordbuffer = getpass("Password: ");
1070
size_t len = strlen(passwordbuffer);
1071
/* Strip trailing newline */
1072
if(len > 0 and passwordbuffer[len-1] == '\n'){
1073
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1074
len--;
1075
}
1076
bret = print_out_password(passwordbuffer, len);
1077
if(not bret){
1078
perror("print_out_password");
1079
exitstatus = EXIT_FAILURE;
1080
}
1081
}
1082
1083
/* Restore old signal handler */
1084
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1085
if(ret == -1){
1086
perror("sigaction");
1087
exitstatus = EXIT_FAILURE;
1088
}
1089
1090
if(custom_argv != NULL){
1091
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1092
free(*arg);
1093
}
1094
free(custom_argv);
1095
}
1096
1097
if(dir != NULL){
1098
closedir(dir);
1099
}
1100
1101
/* Kill the processes */
1102
for(plugin *p = plugin_list; p != NULL; p = p->next){
1103
if(p->pid != 0){
1104
close(p->fd);
1105
ret = kill(p->pid, SIGTERM);
1106
if(ret == -1 and errno != ESRCH){
1107
/* Set-uid proccesses might not get closed */
1108
perror("kill");
1109
}
1110
}
1111
}
1112
1113
/* Wait for any remaining child processes to terminate */
1114
do{
1115
ret = wait(NULL);
1116
} while(ret >= 0);
1117
if(errno != ECHILD){
1118
perror("wait");
1119
}
1120
1121
free_plugin_list();
1122
1123
free(plugindir);
1124
free(argfile);
1125
1126
return exitstatus;
182
1127
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0