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- Committer: Björn Påhlsson
- Date: 2008-07-20 02:52:20 UTC
- Revision ID: belorn@braxen-20080720025220-r5u0388uy9iu23h6
Added following support:
Pluginbased client handler
rewritten Mandos client
Avahi instead of udp server discovery
openpgp encrypted key support
Passprompt stand alone application for direct console input
Added logging for Mandos server
Pluginbased client handler
rewritten Mandos client
Avahi instead of udp server discovery
openpgp encrypted key support
Passprompt stand alone application for direct console input
Added logging for Mandos server
- files added:
- ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- files renamed:
- clients.conf => mandos-clients.conf
- plugin-runner.c => plugbasedclient.c
- plugins.d/mandos-client.c => plugins.d/mandosclient.c
- plugins.d/password-prompt.c => plugins.d/passprompt.c
- mandos => server.py
- files modified:
- Makefile
added
removed
plugbasedclient.c
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
7
*
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
12
*
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
*
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf() */
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
EXIT_SUCCESS, realloc() */
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
36
uid_t, gid_t, getuid(), getgid(),
37
dirfd() */
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
FD_SET(), FD_ISSET(), FD_CLR */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
42
WCOREDUMP() */
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
#include <iso646.h> /* and, or, not */
45
#include <dirent.h> /* DIR, struct dirent, opendir(),
46
readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
50
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
53
close() */
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
FD_CLOEXEC */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal() */
58
#include <errno.h> /* errno */
59
#include <argp.h> /* struct argp_option, struct
60
argp_state, struct argp,
61
argp_parse(), ARGP_ERR_UNKNOWN,
62
ARGP_KEY_END, ARGP_KEY_ARG,
63
error_t */
64
#include <signal.h> /* struct sigaction, sigemptyset(),
65
sigaddset(), sigaction(),
66
sigprocmask(), SIG_BLOCK, SIGCHLD,
67
SIG_UNBLOCK, kill(), sig_atomic_t
68
*/
69
#include <errno.h> /* errno, EBADF */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
71
72
#define BUFFER_SIZE 256
73
74
#define PDIR "/lib/mandos/plugins.d"
75
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
76
77
const char *argp_program_version = "plugin-runner " VERSION;
78
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
79
80
typedef struct plugin{
81
char *name; /* can be NULL or any plugin name */
82
char **argv;
83
int argc;
84
char **environ;
85
int envc;
86
bool disabled;
87
88
/* Variables used for running processes*/
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{
89
19
pid_t pid;
90
20
int fd;
91
21
char *buffer;
92
size_t buffer_size;
93
size_t buffer_length;
94
bool eof;
95
volatile sig_atomic_t completed;
96
int status;
97
struct plugin *next;
98
} plugin;
99
100
static plugin *plugin_list = NULL;
101
102
/* Gets an existing plugin based on name,
103
or if none is found, creates a new one */
104
static plugin *getplugin(char *name){
105
/* Check for exiting plugin with that name */
106
for(plugin *p = plugin_list; p != NULL; p = p->next){
107
if((p->name == name)
108
or (p->name and name and (strcmp(p->name, name) == 0))){
109
return p;
110
}
111
}
112
/* Create a new plugin */
113
plugin *new_plugin = NULL;
114
do {
115
new_plugin = malloc(sizeof(plugin));
116
} while(new_plugin == NULL and errno == EINTR);
117
if(new_plugin == NULL){
118
return NULL;
119
}
120
char *copy_name = NULL;
121
if(name != NULL){
122
do {
123
copy_name = strdup(name);
124
} while(copy_name == NULL and errno == EINTR);
125
if(copy_name == NULL){
126
free(new_plugin);
127
return NULL;
128
}
129
}
130
131
*new_plugin = (plugin){ .name = copy_name,
132
.argc = 1,
133
.disabled = false,
134
.next = plugin_list };
135
136
do {
137
new_plugin->argv = malloc(sizeof(char *) * 2);
138
} while(new_plugin->argv == NULL and errno == EINTR);
139
if(new_plugin->argv == NULL){
140
free(copy_name);
141
free(new_plugin);
142
return NULL;
143
}
144
new_plugin->argv[0] = copy_name;
145
new_plugin->argv[1] = NULL;
146
147
do {
148
new_plugin->environ = malloc(sizeof(char *));
149
} while(new_plugin->environ == NULL and errno == EINTR);
150
if(new_plugin->environ == NULL){
151
free(copy_name);
152
free(new_plugin->argv);
153
free(new_plugin);
154
return NULL;
155
}
156
new_plugin->environ[0] = NULL;
157
158
/* Append the new plugin to the list */
159
plugin_list = new_plugin;
160
return new_plugin;
161
}
162
163
/* Helper function for add_argument and add_environment */
164
static bool add_to_char_array(const char *new, char ***array,
165
int *len){
166
/* Resize the pointed-to array to hold one more pointer */
167
do {
168
*array = realloc(*array, sizeof(char *)
169
* (size_t) ((*len) + 2));
170
} while(*array == NULL and errno == EINTR);
171
/* Malloc check */
172
if(*array == NULL){
173
return false;
174
}
175
/* Make a copy of the new string */
176
char *copy;
177
do {
178
copy = strdup(new);
179
} while(copy == NULL and errno == EINTR);
180
if(copy == NULL){
181
return false;
182
}
183
/* Insert the copy */
184
(*array)[*len] = copy;
185
(*len)++;
186
/* Add a new terminating NULL pointer to the last element */
187
(*array)[*len] = NULL;
188
return true;
189
}
190
191
/* Add to a plugin's argument vector */
192
static bool add_argument(plugin *p, const char *arg){
193
if(p == NULL){
194
return false;
195
}
196
return add_to_char_array(arg, &(p->argv), &(p->argc));
197
}
198
199
/* Add to a plugin's environment */
200
static bool add_environment(plugin *p, const char *def, bool replace){
201
if(p == NULL){
202
return false;
203
}
204
/* namelen = length of name of environment variable */
205
size_t namelen = (size_t)(strchrnul(def, '=') - def);
206
/* Search for this environment variable */
207
for(char **e = p->environ; *e != NULL; e++){
208
if(strncmp(*e, def, namelen + 1) == 0){
209
/* It already exists */
210
if(replace){
211
char *new;
212
do {
213
new = realloc(*e, strlen(def) + 1);
214
} while(new == NULL and errno == EINTR);
215
if(new == NULL){
216
return false;
217
}
218
*e = new;
219
strcpy(*e, def);
220
}
221
return true;
222
}
223
}
224
return add_to_char_array(def, &(p->environ), &(p->envc));
225
}
226
227
/*
228
* Based on the example in the GNU LibC manual chapter 13.13 "File
229
* Descriptor Flags".
230
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
231
*/
232
static int set_cloexec_flag(int fd){
233
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
234
/* If reading the flags failed, return error indication now. */
235
if(ret < 0){
236
return ret;
237
}
238
/* Store modified flag word in the descriptor. */
239
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
240
ret | FD_CLOEXEC));
241
}
242
243
244
/* Mark processes as completed when they exit, and save their exit
245
status. */
246
static void handle_sigchld(__attribute__((unused)) int sig){
247
int old_errno = errno;
248
while(true){
249
plugin *proc = plugin_list;
250
int status;
251
pid_t pid = waitpid(-1, &status, WNOHANG);
252
if(pid == 0){
253
/* Only still running child processes */
254
break;
255
}
256
if(pid == -1){
257
if(errno == ECHILD){
258
/* No child processes */
259
break;
260
}
261
perror("waitpid");
262
}
263
264
/* A child exited, find it in process_list */
265
while(proc != NULL and proc->pid != pid){
266
proc = proc->next;
267
}
268
if(proc == NULL){
269
/* Process not found in process list */
270
continue;
271
}
272
proc->status = status;
273
proc->completed = 1;
274
}
275
errno = old_errno;
276
}
277
278
/* Prints out a password to stdout */
279
static bool print_out_password(const char *buffer, size_t length){
280
ssize_t ret;
281
for(size_t written = 0; written < length; written += (size_t)ret){
282
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
283
length - written));
284
if(ret < 0){
285
return false;
286
}
287
}
288
return true;
289
}
290
291
/* Removes and free a plugin from the plugin list */
292
static void free_plugin(plugin *plugin_node){
293
294
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
295
free(*arg);
296
}
297
free(plugin_node->argv);
298
for(char **env = plugin_node->environ; *env != NULL; env++){
299
free(*env);
300
}
301
free(plugin_node->environ);
302
free(plugin_node->buffer);
303
304
/* Removes the plugin from the singly-linked list */
305
if(plugin_node == plugin_list){
306
/* First one - simple */
307
plugin_list = plugin_list->next;
308
} else {
309
/* Second one or later */
310
for(plugin *p = plugin_list; p != NULL; p = p->next){
311
if(p->next == plugin_node){
312
p->next = plugin_node->next;
313
break;
314
}
315
}
316
}
317
318
free(plugin_node);
319
}
320
321
static void free_plugin_list(void){
322
while(plugin_list != NULL){
323
free_plugin(plugin_list);
324
}
325
}
22
int buffer_size;
23
int buffer_length;
24
struct process *next;
25
} process;
26
27
#define BUFFER_SIZE 256
326
28
327
29
int main(int argc, char *argv[]){
328
char *plugindir = NULL;
329
char *argfile = NULL;
330
FILE *conffp;
331
size_t d_name_len;
332
DIR *dir = NULL;
30
char plugindir[] = "plugins.d";
31
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
32
DIR *dir;
333
33
struct dirent *dirst;
334
34
struct stat st;
335
fd_set rfds_all;
35
fd_set rfds_orig;
336
36
int ret, maxfd = 0;
337
ssize_t sret;
338
uid_t uid = 65534;
339
gid_t gid = 65534;
340
bool debug = false;
341
int exitstatus = EXIT_SUCCESS;
342
struct sigaction old_sigchld_action;
343
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
344
.sa_flags = SA_NOCLDSTOP };
345
char **custom_argv = NULL;
346
int custom_argc = 0;
347
348
/* Establish a signal handler */
349
sigemptyset(&sigchld_action.sa_mask);
350
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
351
if(ret == -1){
352
perror("sigaddset");
353
exitstatus = EXIT_FAILURE;
354
goto fallback;
355
}
356
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
357
if(ret == -1){
358
perror("sigaction");
359
exitstatus = EXIT_FAILURE;
360
goto fallback;
361
}
362
363
/* The options we understand. */
364
struct argp_option options[] = {
365
{ .name = "global-options", .key = 'g',
366
.arg = "OPTION[,OPTION[,...]]",
367
.doc = "Options passed to all plugins" },
368
{ .name = "global-env", .key = 'G',
369
.arg = "VAR=value",
370
.doc = "Environment variable passed to all plugins" },
371
{ .name = "options-for", .key = 'o',
372
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
373
.doc = "Options passed only to specified plugin" },
374
{ .name = "env-for", .key = 'E',
375
.arg = "PLUGIN:ENV=value",
376
.doc = "Environment variable passed to specified plugin" },
377
{ .name = "disable", .key = 'd',
378
.arg = "PLUGIN",
379
.doc = "Disable a specific plugin", .group = 1 },
380
{ .name = "enable", .key = 'e',
381
.arg = "PLUGIN",
382
.doc = "Enable a specific plugin", .group = 1 },
383
{ .name = "plugin-dir", .key = 128,
384
.arg = "DIRECTORY",
385
.doc = "Specify a different plugin directory", .group = 2 },
386
{ .name = "config-file", .key = 129,
387
.arg = "FILE",
388
.doc = "Specify a different configuration file", .group = 2 },
389
{ .name = "userid", .key = 130,
390
.arg = "ID", .flags = 0,
391
.doc = "User ID the plugins will run as", .group = 3 },
392
{ .name = "groupid", .key = 131,
393
.arg = "ID", .flags = 0,
394
.doc = "Group ID the plugins will run as", .group = 3 },
395
{ .name = "debug", .key = 132,
396
.doc = "Debug mode", .group = 4 },
397
{ .name = NULL }
398
};
399
400
error_t parse_opt(int key, char *arg, __attribute__((unused))
401
struct argp_state *state){
402
switch(key){
403
char *tmp;
404
intmax_t tmpmax;
405
case 'g': /* --global-options */
406
if(arg != NULL){
407
char *plugin_option;
408
while((plugin_option = strsep(&arg, ",")) != NULL){
409
if(plugin_option[0] == '\0'){
410
continue;
411
}
412
if(not add_argument(getplugin(NULL), plugin_option)){
413
perror("add_argument");
414
return ARGP_ERR_UNKNOWN;
415
}
416
}
417
}
418
break;
419
case 'G': /* --global-env */
420
if(arg == NULL){
421
break;
422
}
423
if(not add_environment(getplugin(NULL), arg, true)){
424
perror("add_environment");
425
}
426
break;
427
case 'o': /* --options-for */
428
if(arg != NULL){
429
char *plugin_name = strsep(&arg, ":");
430
if(plugin_name[0] == '\0'){
431
break;
432
}
433
char *plugin_option;
434
while((plugin_option = strsep(&arg, ",")) != NULL){
435
if(not add_argument(getplugin(plugin_name), plugin_option)){
436
perror("add_argument");
437
return ARGP_ERR_UNKNOWN;
438
}
439
}
440
}
441
break;
442
case 'E': /* --env-for */
443
if(arg == NULL){
444
break;
445
}
446
{
447
char *envdef = strchr(arg, ':');
448
if(envdef == NULL){
449
break;
450
}
451
*envdef = '\0';
452
if(not add_environment(getplugin(arg), envdef+1, true)){
453
perror("add_environment");
454
}
455
}
456
break;
457
case 'd': /* --disable */
458
if(arg != NULL){
459
plugin *p = getplugin(arg);
460
if(p == NULL){
461
return ARGP_ERR_UNKNOWN;
462
}
463
p->disabled = true;
464
}
465
break;
466
case 'e': /* --enable */
467
if(arg != NULL){
468
plugin *p = getplugin(arg);
469
if(p == NULL){
470
return ARGP_ERR_UNKNOWN;
471
}
472
p->disabled = false;
473
}
474
break;
475
case 128: /* --plugin-dir */
476
free(plugindir);
477
plugindir = strdup(arg);
478
if(plugindir == NULL){
479
perror("strdup");
480
}
481
break;
482
case 129: /* --config-file */
483
/* This is already done by parse_opt_config_file() */
484
break;
485
case 130: /* --userid */
486
errno = 0;
487
tmpmax = strtoimax(arg, &tmp, 10);
488
if(errno != 0 or tmp == arg or *tmp != '\0'
489
or tmpmax != (uid_t)tmpmax){
490
fprintf(stderr, "Bad user ID number: \"%s\", using %"
491
PRIdMAX "\n", arg, (intmax_t)uid);
492
} else {
493
uid = (uid_t)tmpmax;
494
}
495
break;
496
case 131: /* --groupid */
497
errno = 0;
498
tmpmax = strtoimax(arg, &tmp, 10);
499
if(errno != 0 or tmp == arg or *tmp != '\0'
500
or tmpmax != (gid_t)tmpmax){
501
fprintf(stderr, "Bad group ID number: \"%s\", using %"
502
PRIdMAX "\n", arg, (intmax_t)gid);
503
} else {
504
gid = (gid_t)tmpmax;
505
}
506
break;
507
case 132: /* --debug */
508
debug = true;
509
break;
510
/*
511
* When adding more options before this line, remember to also add a
512
* "case" to the "parse_opt_config_file" function below.
513
*/
514
case ARGP_KEY_ARG:
515
/* Cryptsetup always passes an argument, which is an empty
516
string if "none" was specified in /etc/crypttab. So if
517
argument was empty, we ignore it silently. */
518
if(arg[0] != '\0'){
519
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
520
}
521
break;
522
case ARGP_KEY_END:
523
break;
524
default:
525
return ARGP_ERR_UNKNOWN;
526
}
527
return 0;
528
}
529
530
/* This option parser is the same as parse_opt() above, except it
531
ignores everything but the --config-file option. */
532
error_t parse_opt_config_file(int key, char *arg,
533
__attribute__((unused))
534
struct argp_state *state){
535
switch(key){
536
case 'g': /* --global-options */
537
case 'G': /* --global-env */
538
case 'o': /* --options-for */
539
case 'E': /* --env-for */
540
case 'd': /* --disable */
541
case 'e': /* --enable */
542
case 128: /* --plugin-dir */
543
break;
544
case 129: /* --config-file */
545
free(argfile);
546
argfile = strdup(arg);
547
if(argfile == NULL){
548
perror("strdup");
549
}
550
break;
551
case 130: /* --userid */
552
case 131: /* --groupid */
553
case 132: /* --debug */
554
case ARGP_KEY_ARG:
555
case ARGP_KEY_END:
556
break;
557
default:
558
return ARGP_ERR_UNKNOWN;
559
}
560
return 0;
561
}
562
563
struct argp argp = { .options = options,
564
.parser = parse_opt_config_file,
565
.args_doc = "",
566
.doc = "Mandos plugin runner -- Run plugins" };
567
568
/* Parse using parse_opt_config_file() in order to get the custom
569
config file location, if any. */
570
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
571
if(ret == ARGP_ERR_UNKNOWN){
572
fprintf(stderr, "Unknown error while parsing arguments\n");
573
exitstatus = EXIT_FAILURE;
574
goto fallback;
575
}
576
577
/* Reset to the normal argument parser */
578
argp.parser = parse_opt;
579
580
/* Open the configfile if available */
581
if(argfile == NULL){
582
conffp = fopen(AFILE, "r");
583
} else {
584
conffp = fopen(argfile, "r");
585
}
586
if(conffp != NULL){
587
char *org_line = NULL;
588
char *p, *arg, *new_arg, *line;
589
size_t size = 0;
590
const char whitespace_delims[] = " \r\t\f\v\n";
591
const char comment_delim[] = "#";
592
593
custom_argc = 1;
594
custom_argv = malloc(sizeof(char*) * 2);
595
if(custom_argv == NULL){
596
perror("malloc");
597
exitstatus = EXIT_FAILURE;
598
goto fallback;
599
}
600
custom_argv[0] = argv[0];
601
custom_argv[1] = NULL;
602
603
/* for each line in the config file, strip whitespace and ignore
604
commented text */
605
while(true){
606
sret = getline(&org_line, &size, conffp);
607
if(sret == -1){
608
break;
609
}
610
611
line = org_line;
612
arg = strsep(&line, comment_delim);
613
while((p = strsep(&arg, whitespace_delims)) != NULL){
614
if(p[0] == '\0'){
615
continue;
616
}
617
new_arg = strdup(p);
618
if(new_arg == NULL){
619
perror("strdup");
620
exitstatus = EXIT_FAILURE;
621
free(org_line);
622
goto fallback;
623
}
624
625
custom_argc += 1;
626
custom_argv = realloc(custom_argv, sizeof(char *)
627
* ((unsigned int) custom_argc + 1));
628
if(custom_argv == NULL){
629
perror("realloc");
630
exitstatus = EXIT_FAILURE;
631
free(org_line);
632
goto fallback;
633
}
634
custom_argv[custom_argc-1] = new_arg;
635
custom_argv[custom_argc] = NULL;
636
}
637
}
638
do {
639
ret = fclose(conffp);
640
} while(ret == EOF and errno == EINTR);
641
if(ret == EOF){
642
perror("fclose");
643
exitstatus = EXIT_FAILURE;
644
goto fallback;
645
}
646
free(org_line);
647
} else {
648
/* Check for harmful errors and go to fallback. Other errors might
649
not affect opening plugins */
650
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
651
perror("fopen");
652
exitstatus = EXIT_FAILURE;
653
goto fallback;
654
}
655
}
656
/* If there was any arguments from configuration file,
657
pass them to parser as command arguments */
658
if(custom_argv != NULL){
659
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
660
0, NULL);
661
if(ret == ARGP_ERR_UNKNOWN){
662
fprintf(stderr, "Unknown error while parsing arguments\n");
663
exitstatus = EXIT_FAILURE;
664
goto fallback;
665
}
666
}
667
668
/* Parse actual command line arguments, to let them override the
669
config file */
670
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
671
if(ret == ARGP_ERR_UNKNOWN){
672
fprintf(stderr, "Unknown error while parsing arguments\n");
673
exitstatus = EXIT_FAILURE;
674
goto fallback;
675
}
676
677
if(debug){
678
for(plugin *p = plugin_list; p != NULL; p=p->next){
679
fprintf(stderr, "Plugin: %s has %d arguments\n",
680
p->name ? p->name : "Global", p->argc - 1);
681
for(char **a = p->argv; *a != NULL; a++){
682
fprintf(stderr, "\tArg: %s\n", *a);
683
}
684
fprintf(stderr, "...and %d environment variables\n", p->envc);
685
for(char **a = p->environ; *a != NULL; a++){
686
fprintf(stderr, "\t%s\n", *a);
687
}
688
}
689
}
690
691
/* Strip permissions down to nobody */
692
setgid(gid);
693
if(ret == -1){
694
perror("setgid");
695
}
696
ret = setuid(uid);
697
if(ret == -1){
698
perror("setuid");
699
}
700
701
if(plugindir == NULL){
702
dir = opendir(PDIR);
703
} else {
704
dir = opendir(plugindir);
705
}
706
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
707
41
if(dir == NULL){
708
perror("Could not open plugin dir");
709
exitstatus = EXIT_FAILURE;
710
goto fallback;
711
}
712
713
/* Set the FD_CLOEXEC flag on the directory, if possible */
714
{
715
int dir_fd = dirfd(dir);
716
if(dir_fd >= 0){
717
ret = set_cloexec_flag(dir_fd);
718
if(ret < 0){
719
perror("set_cloexec_flag");
720
exitstatus = EXIT_FAILURE;
721
goto fallback;
722
}
723
}
724
}
725
726
FD_ZERO(&rfds_all);
727
728
/* Read and execute any executable in the plugin directory*/
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
729
48
while(true){
730
do {
731
dirst = readdir(dir);
732
} while(dirst == NULL and errno == EINTR);
49
dirst = readdir(dir);
733
50
734
/* All directory entries have been processed */
51
// All directory entries have been processed
735
52
if(dirst == NULL){
736
if(errno == EBADF){
737
perror("readdir");
738
exitstatus = EXIT_FAILURE;
739
goto fallback;
740
}
741
53
break;
742
54
}
743
55
744
56
d_name_len = strlen(dirst->d_name);
745
57
746
/* Ignore dotfiles, backup files and other junk */
747
{
748
bool bad_name = false;
749
750
const char const *bad_prefixes[] = { ".", "#", NULL };
751
752
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
753
".dpkg-old",
754
".dpkg-bak",
755
".dpkg-divert", NULL };
756
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
757
size_t pre_len = strlen(*pre);
758
if((d_name_len >= pre_len)
759
and strncmp((dirst->d_name), *pre, pre_len) == 0){
760
if(debug){
761
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
762
" with bad prefix %s\n", dirst->d_name, *pre);
763
}
764
bad_name = true;
765
break;
766
}
767
}
768
if(bad_name){
769
continue;
770
}
771
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
772
size_t suf_len = strlen(*suf);
773
if((d_name_len >= suf_len)
774
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
775
== 0)){
776
if(debug){
777
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
778
" with bad suffix %s\n", dirst->d_name, *suf);
779
}
780
bad_name = true;
781
break;
782
}
783
}
784
785
if(bad_name){
786
continue;
787
}
788
}
789
790
char *filename;
791
if(plugindir == NULL){
792
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
793
dirst->d_name));
794
} else {
795
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
796
plugindir,
797
dirst->d_name));
798
}
799
if(ret < 0){
800
perror("asprintf");
801
continue;
802
}
803
804
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
805
if(ret == -1){
806
perror("stat");
807
free(filename);
808
continue;
809
}
810
811
/* Ignore non-executable files */
812
if(not S_ISREG(st.st_mode)
813
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
814
if(debug){
815
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
816
" with bad type or mode\n", filename);
817
}
818
free(filename);
819
continue;
820
}
821
822
plugin *p = getplugin(dirst->d_name);
823
if(p == NULL){
824
perror("getplugin");
825
free(filename);
826
continue;
827
}
828
if(p->disabled){
829
if(debug){
830
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
831
dirst->d_name);
832
}
833
free(filename);
834
continue;
835
}
836
{
837
/* Add global arguments to argument list for this plugin */
838
plugin *g = getplugin(NULL);
839
if(g != NULL){
840
for(char **a = g->argv + 1; *a != NULL; a++){
841
if(not add_argument(p, *a)){
842
perror("add_argument");
843
}
844
}
845
/* Add global environment variables */
846
for(char **e = g->environ; *e != NULL; e++){
847
if(not add_environment(p, *e, false)){
848
perror("add_environment");
849
}
850
}
851
}
852
}
853
/* If this plugin has any environment variables, we will call
854
using execve and need to duplicate the environment from this
855
process, too. */
856
if(p->environ[0] != NULL){
857
for(char **e = environ; *e != NULL; e++){
858
if(not add_environment(p, *e, false)){
859
perror("add_environment");
860
}
861
}
862
}
863
864
int pipefd[2];
865
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
866
if(ret == -1){
867
perror("pipe");
868
exitstatus = EXIT_FAILURE;
869
goto fallback;
870
}
871
/* Ask OS to automatic close the pipe on exec */
872
ret = set_cloexec_flag(pipefd[0]);
873
if(ret < 0){
874
perror("set_cloexec_flag");
875
exitstatus = EXIT_FAILURE;
876
goto fallback;
877
}
878
ret = set_cloexec_flag(pipefd[1]);
879
if(ret < 0){
880
perror("set_cloexec_flag");
881
exitstatus = EXIT_FAILURE;
882
goto fallback;
883
}
884
/* Block SIGCHLD until process is safely in process list */
885
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
886
&sigchld_action.sa_mask,
887
NULL));
888
if(ret < 0){
889
perror("sigprocmask");
890
exitstatus = EXIT_FAILURE;
891
goto fallback;
892
}
893
/* Starting a new process to be watched */
894
pid_t pid;
895
do {
896
pid = fork();
897
} while(pid == -1 and errno == EINTR);
898
if(pid == -1){
899
perror("fork");
900
exitstatus = EXIT_FAILURE;
901
goto fallback;
902
}
903
if(pid == 0){
904
/* this is the child process */
905
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
906
if(ret < 0){
907
perror("sigaction");
908
_exit(EXIT_FAILURE);
909
}
910
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
911
if(ret < 0){
912
perror("sigprocmask");
913
_exit(EXIT_FAILURE);
914
}
915
916
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
917
if(ret == -1){
918
perror("dup2");
919
_exit(EXIT_FAILURE);
920
}
921
922
if(dirfd(dir) < 0){
923
/* If dir has no file descriptor, we could not set FD_CLOEXEC
924
above and must now close it manually here. */
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 */
925
79
closedir(dir);
926
}
927
if(p->environ[0] == NULL){
928
if(execv(filename, p->argv) < 0){
929
perror("execv");
930
_exit(EXIT_FAILURE);
931
}
932
} else {
933
if(execve(filename, p->argv, p->environ) < 0){
934
perror("execve");
935
_exit(EXIT_FAILURE);
936
}
937
}
938
/* no return */
939
}
940
/* Parent process */
941
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
942
pipe */
943
free(filename);
944
plugin *new_plugin = getplugin(dirst->d_name);
945
if(new_plugin == NULL){
946
perror("getplugin");
947
ret = (int)(TEMP_FAILURE_RETRY
948
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
949
NULL)));
950
if(ret < 0){
951
perror("sigprocmask");
952
}
953
exitstatus = EXIT_FAILURE;
954
goto fallback;
955
}
956
957
new_plugin->pid = pid;
958
new_plugin->fd = pipefd[0];
959
960
/* Unblock SIGCHLD so signal handler can be run if this process
961
has already completed */
962
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
963
&sigchld_action.sa_mask,
964
NULL));
965
if(ret < 0){
966
perror("sigprocmask");
967
exitstatus = EXIT_FAILURE;
968
goto fallback;
969
}
970
971
FD_SET(new_plugin->fd, &rfds_all);
972
973
if(maxfd < new_plugin->fd){
974
maxfd = new_plugin->fd;
975
}
976
}
977
978
TEMP_FAILURE_RETRY(closedir(dir));
979
dir = NULL;
980
free_plugin(getplugin(NULL));
981
982
for(plugin *p = plugin_list; p != NULL; p = p->next){
983
if(p->pid != 0){
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;
114
}
115
}
116
117
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
}
984
178
break;
985
179
}
986
if(p->next == NULL){
987
fprintf(stderr, "No plugin processes started. Incorrect plugin"
988
" directory?\n");
989
free_plugin_list();
990
}
991
}
992
993
/* Main loop while running plugins exist */
994
while(plugin_list){
995
fd_set rfds = rfds_all;
996
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
997
if(select_ret == -1 and errno != EINTR){
998
perror("select");
999
exitstatus = EXIT_FAILURE;
1000
goto fallback;
1001
}
1002
/* OK, now either a process completed, or something can be read
1003
from one of them */
1004
for(plugin *proc = plugin_list; proc != NULL;){
1005
/* Is this process completely done? */
1006
if(proc->completed and proc->eof){
1007
/* Only accept the plugin output if it exited cleanly */
1008
if(not WIFEXITED(proc->status)
1009
or WEXITSTATUS(proc->status) != 0){
1010
/* Bad exit by plugin */
1011
1012
if(debug){
1013
if(WIFEXITED(proc->status)){
1014
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1015
" status %d\n", proc->name,
1016
(intmax_t) (proc->pid),
1017
WEXITSTATUS(proc->status));
1018
} else if(WIFSIGNALED(proc->status)){
1019
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1020
" signal %d: %s\n", proc->name,
1021
(intmax_t) (proc->pid),
1022
WTERMSIG(proc->status),
1023
strsignal(WTERMSIG(proc->status)));
1024
} else if(WCOREDUMP(proc->status)){
1025
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1026
" core\n", proc->name, (intmax_t) (proc->pid));
1027
}
1028
}
1029
1030
/* Remove the plugin */
1031
FD_CLR(proc->fd, &rfds_all);
1032
1033
/* Block signal while modifying process_list */
1034
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1035
(SIG_BLOCK,
1036
&sigchld_action.sa_mask,
1037
NULL));
1038
if(ret < 0){
1039
perror("sigprocmask");
1040
exitstatus = EXIT_FAILURE;
1041
goto fallback;
1042
}
1043
1044
plugin *next_plugin = proc->next;
1045
free_plugin(proc);
1046
proc = next_plugin;
1047
1048
/* We are done modifying process list, so unblock signal */
1049
ret = (int)(TEMP_FAILURE_RETRY
1050
(sigprocmask(SIG_UNBLOCK,
1051
&sigchld_action.sa_mask, NULL)));
1052
if(ret < 0){
1053
perror("sigprocmask");
1054
exitstatus = EXIT_FAILURE;
1055
goto fallback;
1056
}
1057
1058
if(plugin_list == NULL){
1059
break;
1060
}
1061
1062
continue;
1063
}
1064
1065
/* This process exited nicely, so print its buffer */
1066
1067
bool bret = print_out_password(proc->buffer,
1068
proc->buffer_length);
1069
if(not bret){
1070
perror("print_out_password");
1071
exitstatus = EXIT_FAILURE;
1072
}
1073
goto fallback;
1074
}
1075
1076
/* This process has not completed. Does it have any output? */
1077
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1078
/* This process had nothing to say at this time */
1079
proc = proc->next;
1080
continue;
1081
}
1082
/* Before reading, make the process' data buffer large enough */
1083
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1084
proc->buffer = realloc(proc->buffer, proc->buffer_size
1085
+ (size_t) BUFFER_SIZE);
1086
if(proc->buffer == NULL){
1087
perror("malloc");
1088
exitstatus = EXIT_FAILURE;
1089
goto fallback;
1090
}
1091
proc->buffer_size += BUFFER_SIZE;
1092
}
1093
/* Read from the process */
1094
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1095
proc->buffer
1096
+ proc->buffer_length,
1097
BUFFER_SIZE));
1098
if(sret < 0){
1099
/* Read error from this process; ignore the error */
1100
proc = proc->next;
1101
continue;
1102
}
1103
if(sret == 0){
1104
/* got EOF */
1105
proc->eof = true;
1106
} else {
1107
proc->buffer_length += (size_t) sret;
1108
}
1109
}
1110
}
1111
1112
1113
fallback:
1114
1115
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1116
/* Fallback if all plugins failed, none are found or an error
1117
occured */
1118
bool bret;
1119
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1120
char *passwordbuffer = getpass("Password: ");
1121
size_t len = strlen(passwordbuffer);
1122
/* Strip trailing newline */
1123
if(len > 0 and passwordbuffer[len-1] == '\n'){
1124
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1125
len--;
1126
}
1127
bret = print_out_password(passwordbuffer, len);
1128
if(not bret){
1129
perror("print_out_password");
1130
exitstatus = EXIT_FAILURE;
1131
}
1132
}
1133
1134
/* Restore old signal handler */
1135
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1136
if(ret == -1){
1137
perror("sigaction");
1138
exitstatus = EXIT_FAILURE;
1139
}
1140
1141
if(custom_argv != NULL){
1142
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1143
free(*arg);
1144
}
1145
free(custom_argv);
1146
}
1147
1148
if(dir != NULL){
1149
closedir(dir);
1150
}
1151
1152
/* Kill the processes */
1153
for(plugin *p = plugin_list; p != NULL; p = p->next){
1154
if(p->pid != 0){
1155
close(p->fd);
1156
ret = kill(p->pid, SIGTERM);
1157
if(ret == -1 and errno != ESRCH){
1158
/* Set-uid proccesses might not get closed */
1159
perror("kill");
1160
}
1161
}
1162
}
1163
1164
/* Wait for any remaining child processes to terminate */
1165
do {
1166
ret = wait(NULL);
1167
} while(ret >= 0);
1168
if(errno != ECHILD){
1169
perror("wait");
1170
}
1171
1172
free_plugin_list();
1173
1174
free(plugindir);
1175
free(argfile);
1176
1177
return exitstatus;
180
}
181
return EXIT_SUCCESS;
1178
182
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0