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- Committer: Teddy Hogeborn
- Date: 2008-09-07 01:20:43 UTC
- Revision ID: teddy@fukt.bsnet.se-20080907012043-w05a7qh6258eqh27
* Makefile: Clearly separate "local" install variable settings from
"package" variable settings.
(INITRAMFSTOOLS): New variable.
(install-server): Use $(DESTDIR) to install init script and
/etc/default file.
(install-client): Use $(INITRAMFSTOOLS).
(uninstall-client): - '' -
(purge-server): Use $(DESTDIR).
"package" variable settings.
(INITRAMFSTOOLS): New variable.
(install-server): Use $(DESTDIR) to install init script and
/etc/default file.
(install-client): Use $(INITRAMFSTOOLS).
(uninstall-client): - '' -
(purge-server): Use $(DESTDIR).
- files added:
- .bzrignore
- 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 © 2007-2008 Teddy Hogeborn & Björn Påhlsson
6
*
7
* This program is free software: you can redistribute it and/or
8
* modify it under the terms of the GNU General Public License as
9
* published by the Free Software Foundation, either version 3 of the
10
* License, or (at your option) any later version.
11
*
12
* This program is distributed in the hope that it will be useful, but
13
* WITHOUT ANY WARRANTY; without even the implied warranty of
14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15
* General Public License for more details.
16
*
17
* You should have received a copy of the GNU General Public License
18
* along with this program. If not, see
19
* <http://www.gnu.org/licenses/>.
20
*
21
* Contact the authors at <mandos@fukt.bsnet.se>.
22
*/
23
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
25
asprintf() */
26
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
stat, waitpid(), WIFEXITED(),
34
WEXITSTATUS(), wait(), pid_t,
35
uid_t, gid_t, getuid(), getgid(),
36
dirfd() */
37
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
FD_SET(), FD_ISSET(), FD_CLR */
39
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
40
WEXITSTATUS() */
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
44
readdir(), closedir(), dirfd() */
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
46
fcntl(), setuid(), setgid(),
47
F_GETFD, F_SETFD, FD_CLOEXEC,
48
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
50
execv(), write(), read(),
51
close() */
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC */
54
#include <string.h> /* strsep, strlen(), asprintf() */
55
#include <errno.h> /* errno */
56
#include <argp.h> /* struct argp_option, struct
57
argp_state, struct argp,
58
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG,
60
error_t */
61
#include <signal.h> /* struct sigaction, sigemptyset(),
62
sigaddset(), sigaction(),
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
#include <errno.h> /* errno, EBADF */
66
67
#define BUFFER_SIZE 256
68
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
71
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
75
struct plugin;
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
return NULL;
119
}
120
}
121
122
*new_plugin = (plugin) { .name = copy_name,
123
.argc = 1,
124
.disabled = false,
125
.next = plugin_list };
126
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
129
free(copy_name);
130
free(new_plugin);
131
return NULL;
132
}
133
new_plugin->argv[0] = copy_name;
134
new_plugin->argv[1] = NULL;
135
136
new_plugin->environ = malloc(sizeof(char *));
137
if(new_plugin->environ == NULL){
138
free(copy_name);
139
free(new_plugin->argv);
140
free(new_plugin);
141
return NULL;
142
}
143
new_plugin->environ[0] = NULL;
144
145
/* Append the new plugin to the list */
146
plugin_list = new_plugin;
147
return new_plugin;
148
}
149
150
/* Helper function for add_argument and add_environment */
151
static bool add_to_char_array(const char *new, char ***array,
152
int *len){
153
/* Resize the pointed-to array to hold one more pointer */
154
*array = realloc(*array, sizeof(char *)
155
* (size_t) ((*len) + 2));
156
/* Malloc check */
157
if(*array == NULL){
158
return false;
159
}
160
/* Make a copy of the new string */
161
char *copy = strdup(new);
162
if(copy == NULL){
163
return false;
164
}
165
/* Insert the copy */
166
(*array)[*len] = copy;
167
(*len)++;
168
/* Add a new terminating NULL pointer to the last element */
169
(*array)[*len] = NULL;
170
return true;
171
}
172
173
/* Add to a plugin's argument vector */
174
static bool add_argument(plugin *p, const char *arg){
175
if(p == NULL){
176
return false;
177
}
178
return add_to_char_array(arg, &(p->argv), &(p->argc));
179
}
180
181
/* Add to a plugin's environment */
182
static bool add_environment(plugin *p, const char *def, bool replace){
183
if(p == NULL){
184
return false;
185
}
186
/* namelen = length of name of environment variable */
187
size_t namelen = (size_t)(strchrnul(def, '=') - def);
188
/* Search for this environment variable */
189
for(char **e = p->environ; *e != NULL; e++){
190
if(strncmp(*e, def, namelen + 1) == 0){
191
/* It already exists */
192
if(replace){
193
char *new = realloc(*e, strlen(def) + 1);
194
if(new == NULL){
195
return false;
196
}
197
*e = new;
198
strcpy(*e, def);
199
}
200
return true;
201
}
202
}
203
return add_to_char_array(def, &(p->environ), &(p->envc));
204
}
205
206
/*
207
* Based on the example in the GNU LibC manual chapter 13.13 "File
208
* Descriptor Flags".
209
* *Note File Descriptor Flags:(libc)Descriptor Flags.
210
*/
211
static int set_cloexec_flag(int fd)
212
{
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
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
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;
312
fd_set rfds_all;
36
313
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
314
uid_t uid = 65534;
315
gid_t gid = 65534;
316
bool debug = false;
317
int exitstatus = EXIT_SUCCESS;
318
struct sigaction old_sigchld_action;
319
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
320
.sa_flags = SA_NOCLDSTOP };
321
char **custom_argv = NULL;
322
int custom_argc = 0;
323
324
/* Establish a signal handler */
325
sigemptyset(&sigchld_action.sa_mask);
326
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
327
if(ret == -1){
328
perror("sigaddset");
329
exitstatus = EXIT_FAILURE;
330
goto fallback;
331
}
332
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
333
if(ret == -1){
334
perror("sigaction");
335
exitstatus = EXIT_FAILURE;
336
goto fallback;
337
}
338
339
/* The options we understand. */
340
struct argp_option options[] = {
341
{ .name = "global-options", .key = 'g',
342
.arg = "OPTION[,OPTION[,...]]",
343
.doc = "Options passed to all plugins" },
344
{ .name = "global-env", .key = 'G',
345
.arg = "VAR=value",
346
.doc = "Environment variable passed to all plugins" },
347
{ .name = "options-for", .key = 'o',
348
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
349
.doc = "Options passed only to specified plugin" },
350
{ .name = "env-for", .key = 'E',
351
.arg = "PLUGIN:ENV=value",
352
.doc = "Environment variable passed to specified plugin" },
353
{ .name = "disable", .key = 'd',
354
.arg = "PLUGIN",
355
.doc = "Disable a specific plugin", .group = 1 },
356
{ .name = "enable", .key = 'e',
357
.arg = "PLUGIN",
358
.doc = "Enable a specific plugin", .group = 1 },
359
{ .name = "plugin-dir", .key = 128,
360
.arg = "DIRECTORY",
361
.doc = "Specify a different plugin directory", .group = 2 },
362
{ .name = "config-file", .key = 129,
363
.arg = "FILE",
364
.doc = "Specify a different configuration file", .group = 2 },
365
{ .name = "userid", .key = 130,
366
.arg = "ID", .flags = 0,
367
.doc = "User ID the plugins will run as", .group = 3 },
368
{ .name = "groupid", .key = 131,
369
.arg = "ID", .flags = 0,
370
.doc = "Group ID the plugins will run as", .group = 3 },
371
{ .name = "debug", .key = 132,
372
.doc = "Debug mode", .group = 4 },
373
{ .name = NULL }
374
};
375
376
error_t parse_opt (int key, char *arg, __attribute__((unused))
377
struct argp_state *state) {
378
switch (key) {
379
case 'g': /* --global-options */
380
if (arg != NULL){
381
char *p;
382
while((p = strsep(&arg, ",")) != NULL){
383
if(p[0] == '\0'){
384
continue;
385
}
386
if(not add_argument(getplugin(NULL), p)){
387
perror("add_argument");
388
return ARGP_ERR_UNKNOWN;
389
}
390
}
391
}
392
break;
393
case 'G': /* --global-env */
394
if(arg == NULL){
395
break;
396
}
397
{
398
char *envdef = strdup(arg);
399
if(envdef == NULL){
400
break;
401
}
402
if(not add_environment(getplugin(NULL), envdef, true)){
403
perror("add_environment");
404
}
405
}
406
break;
407
case 'o': /* --options-for */
408
if (arg != NULL){
409
char *p_name = strsep(&arg, ":");
410
if(p_name[0] == '\0' or arg == NULL){
411
break;
412
}
413
char *opt = strsep(&arg, ":");
414
if(opt[0] == '\0' or opt == NULL){
415
break;
416
}
417
char *p;
418
while((p = strsep(&opt, ",")) != NULL){
419
if(p[0] == '\0'){
420
continue;
421
}
422
if(not add_argument(getplugin(p_name), p)){
423
perror("add_argument");
424
return ARGP_ERR_UNKNOWN;
425
}
426
}
427
}
428
break;
429
case 'E': /* --env-for */
430
if(arg == NULL){
431
break;
432
}
433
{
434
char *envdef = strchr(arg, ':');
435
if(envdef == NULL){
436
break;
437
}
438
char *p_name = strndup(arg, (size_t) (envdef-arg));
439
if(p_name == NULL){
440
break;
441
}
442
envdef++;
443
if(not add_environment(getplugin(p_name), envdef, true)){
444
perror("add_environment");
445
}
446
}
447
break;
448
case 'd': /* --disable */
449
if (arg != NULL){
450
plugin *p = getplugin(arg);
451
if(p == NULL){
452
return ARGP_ERR_UNKNOWN;
453
}
454
p->disabled = true;
455
}
456
break;
457
case 'e': /* --enable */
458
if (arg != NULL){
459
plugin *p = getplugin(arg);
460
if(p == NULL){
461
return ARGP_ERR_UNKNOWN;
462
}
463
p->disabled = false;
464
}
465
break;
466
case 128: /* --plugin-dir */
467
plugindir = strdup(arg);
468
if(plugindir == NULL){
469
perror("strdup");
470
}
471
break;
472
case 129: /* --config-file */
473
/* This is already done by parse_opt_config_file() */
474
break;
475
case 130: /* --userid */
476
uid = (uid_t)strtol(arg, NULL, 10);
477
break;
478
case 131: /* --groupid */
479
gid = (gid_t)strtol(arg, NULL, 10);
480
break;
481
case 132: /* --debug */
482
debug = true;
483
break;
484
case ARGP_KEY_ARG:
485
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
486
break;
487
case ARGP_KEY_END:
488
break;
489
default:
490
return ARGP_ERR_UNKNOWN;
491
}
492
return 0;
493
}
494
495
/* This option parser is the same as parse_opt() above, except it
496
ignores everything but the --config-file option. */
497
error_t parse_opt_config_file (int key, char *arg,
498
__attribute__((unused))
499
struct argp_state *state) {
500
switch (key) {
501
case 'g': /* --global-options */
502
case 'G': /* --global-env */
503
case 'o': /* --options-for */
504
case 'E': /* --env-for */
505
case 'd': /* --disable */
506
case 'e': /* --enable */
507
case 128: /* --plugin-dir */
508
break;
509
case 129: /* --config-file */
510
argfile = strdup(arg);
511
if(argfile == NULL){
512
perror("strdup");
513
}
514
break;
515
case 130: /* --userid */
516
case 131: /* --groupid */
517
case 132: /* --debug */
518
case ARGP_KEY_ARG:
519
case ARGP_KEY_END:
520
break;
521
default:
522
return ARGP_ERR_UNKNOWN;
523
}
524
return 0;
525
}
526
527
struct argp argp = { .options = options,
528
.parser = parse_opt_config_file,
529
.args_doc = "",
530
.doc = "Mandos plugin runner -- Run plugins" };
531
532
/* Parse using the parse_opt_config_file in order to get the custom
533
config file location, if any. */
534
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
535
if (ret == ARGP_ERR_UNKNOWN){
536
fprintf(stderr, "Unknown error while parsing arguments\n");
537
exitstatus = EXIT_FAILURE;
538
goto fallback;
539
}
540
541
/* Reset to the normal argument parser */
542
argp.parser = parse_opt;
543
544
/* Open the configfile if available */
545
if (argfile == NULL){
546
conffp = fopen(AFILE, "r");
547
} else {
548
conffp = fopen(argfile, "r");
549
}
550
if(conffp != NULL){
551
char *org_line = NULL;
552
char *p, *arg, *new_arg, *line;
553
size_t size = 0;
554
ssize_t sret;
555
const char whitespace_delims[] = " \r\t\f\v\n";
556
const char comment_delim[] = "#";
557
558
custom_argc = 1;
559
custom_argv = malloc(sizeof(char*) * 2);
560
if(custom_argv == NULL){
561
perror("malloc");
562
exitstatus = EXIT_FAILURE;
563
goto fallback;
564
}
565
custom_argv[0] = argv[0];
566
custom_argv[1] = NULL;
567
568
/* for each line in the config file, strip whitespace and ignore
569
commented text */
570
while(true){
571
sret = getline(&org_line, &size, conffp);
572
if(sret == -1){
573
break;
574
}
575
576
line = org_line;
577
arg = strsep(&line, comment_delim);
578
while((p = strsep(&arg, whitespace_delims)) != NULL){
579
if(p[0] == '\0'){
580
continue;
581
}
582
new_arg = strdup(p);
583
if(new_arg == NULL){
584
perror("strdup");
585
exitstatus = EXIT_FAILURE;
586
free(org_line);
587
goto fallback;
588
}
589
590
custom_argc += 1;
591
custom_argv = realloc(custom_argv, sizeof(char *)
592
* ((unsigned int) custom_argc + 1));
593
if(custom_argv == NULL){
594
perror("realloc");
595
exitstatus = EXIT_FAILURE;
596
free(org_line);
597
goto fallback;
598
}
599
custom_argv[custom_argc-1] = new_arg;
600
custom_argv[custom_argc] = NULL;
601
}
602
}
603
free(org_line);
604
} else {
605
/* Check for harmful errors and go to fallback. Other errors might
606
not affect opening plugins */
607
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
608
perror("fopen");
609
exitstatus = EXIT_FAILURE;
610
goto fallback;
611
}
612
}
613
/* If there was any arguments from configuration file,
614
pass them to parser as command arguments */
615
if(custom_argv != NULL){
616
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
617
0, NULL);
618
if (ret == ARGP_ERR_UNKNOWN){
619
fprintf(stderr, "Unknown error while parsing arguments\n");
620
exitstatus = EXIT_FAILURE;
621
goto fallback;
622
}
623
}
624
625
/* Parse actual command line arguments, to let them override the
626
config file */
627
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
628
if (ret == ARGP_ERR_UNKNOWN){
629
fprintf(stderr, "Unknown error while parsing arguments\n");
630
exitstatus = EXIT_FAILURE;
631
goto fallback;
632
}
633
634
if(debug){
635
for(plugin *p = plugin_list; p != NULL; p=p->next){
636
fprintf(stderr, "Plugin: %s has %d arguments\n",
637
p->name ? p->name : "Global", p->argc - 1);
638
for(char **a = p->argv; *a != NULL; a++){
639
fprintf(stderr, "\tArg: %s\n", *a);
640
}
641
fprintf(stderr, "...and %u environment variables\n", p->envc);
642
for(char **a = p->environ; *a != NULL; a++){
643
fprintf(stderr, "\t%s\n", *a);
644
}
645
}
646
}
647
648
/* Strip permissions down to nobody */
649
ret = setuid(uid);
650
if (ret == -1){
651
perror("setuid");
652
}
653
setgid(gid);
654
if (ret == -1){
655
perror("setgid");
656
}
657
658
if (plugindir == NULL){
659
dir = opendir(PDIR);
660
} else {
661
dir = opendir(plugindir);
662
}
663
41
664
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
665
perror("Could not open plugin dir");
666
exitstatus = EXIT_FAILURE;
667
goto fallback;
668
}
669
670
/* Set the FD_CLOEXEC flag on the directory, if possible */
671
{
672
int dir_fd = dirfd(dir);
673
if(dir_fd >= 0){
674
ret = set_cloexec_flag(dir_fd);
675
if(ret < 0){
676
perror("set_cloexec_flag");
677
exitstatus = EXIT_FAILURE;
678
goto fallback;
679
}
680
}
681
}
682
683
FD_ZERO(&rfds_all);
684
685
/* Read and execute any executable in the plugin directory*/
48
686
while(true){
49
687
dirst = readdir(dir);
50
688
51
// All directory entries have been processed
689
/* All directory entries have been processed */
52
690
if(dirst == NULL){
691
if (errno == EBADF){
692
perror("readdir");
693
exitstatus = EXIT_FAILURE;
694
goto fallback;
695
}
53
696
break;
54
697
}
55
698
56
699
d_name_len = strlen(dirst->d_name);
57
700
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 */
701
/* Ignore dotfiles, backup files and other junk */
702
{
703
bool bad_name = false;
704
705
const char const *bad_prefixes[] = { ".", "#", NULL };
706
707
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
708
".dpkg-old",
709
".dpkg-divert", NULL };
710
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
711
size_t pre_len = strlen(*pre);
712
if((d_name_len >= pre_len)
713
and strncmp((dirst->d_name), *pre, pre_len) == 0){
714
if(debug){
715
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
716
" with bad prefix %s\n", dirst->d_name, *pre);
717
}
718
bad_name = true;
719
break;
720
}
721
}
722
if(bad_name){
723
continue;
724
}
725
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
726
size_t suf_len = strlen(*suf);
727
if((d_name_len >= suf_len)
728
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
729
== 0)){
730
if(debug){
731
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
732
" with bad suffix %s\n", dirst->d_name, *suf);
733
}
734
bad_name = true;
735
break;
736
}
737
}
738
739
if(bad_name){
740
continue;
741
}
742
}
743
744
char *filename;
745
if(plugindir == NULL){
746
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
747
} else {
748
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
749
}
750
if(ret < 0){
751
perror("asprintf");
752
continue;
753
}
754
755
ret = stat(filename, &st);
756
if (ret == -1){
757
perror("stat");
758
free(filename);
759
continue;
760
}
761
762
/* Ignore non-executable files */
763
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
764
if(debug){
765
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
766
" with bad type or mode\n", filename);
767
}
768
free(filename);
769
continue;
770
}
771
772
plugin *p = getplugin(dirst->d_name);
773
if(p == NULL){
774
perror("getplugin");
775
free(filename);
776
continue;
777
}
778
if(p->disabled){
779
if(debug){
780
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
781
dirst->d_name);
782
}
783
free(filename);
784
continue;
785
}
786
{
787
/* Add global arguments to argument list for this plugin */
788
plugin *g = getplugin(NULL);
789
if(g != NULL){
790
for(char **a = g->argv + 1; *a != NULL; a++){
791
if(not add_argument(p, *a)){
792
perror("add_argument");
793
}
794
}
795
/* Add global environment variables */
796
for(char **e = g->environ; *e != NULL; e++){
797
if(not add_environment(p, *e, false)){
798
perror("add_environment");
799
}
800
}
801
}
802
}
803
/* If this plugin has any environment variables, we will call
804
using execve and need to duplicate the environment from this
805
process, too. */
806
if(p->environ[0] != NULL){
807
for(char **e = environ; *e != NULL; e++){
808
if(not add_environment(p, *e, false)){
809
perror("add_environment");
810
}
811
}
812
}
813
814
int pipefd[2];
815
ret = pipe(pipefd);
816
if (ret == -1){
817
perror("pipe");
818
exitstatus = EXIT_FAILURE;
819
goto fallback;
820
}
821
/* Ask OS to automatic close the pipe on exec */
822
ret = set_cloexec_flag(pipefd[0]);
823
if(ret < 0){
824
perror("set_cloexec_flag");
825
exitstatus = EXIT_FAILURE;
826
goto fallback;
827
}
828
ret = set_cloexec_flag(pipefd[1]);
829
if(ret < 0){
830
perror("set_cloexec_flag");
831
exitstatus = EXIT_FAILURE;
832
goto fallback;
833
}
834
/* Block SIGCHLD until process is safely in process list */
835
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
836
if(ret < 0){
837
perror("sigprocmask");
838
exitstatus = EXIT_FAILURE;
839
goto fallback;
840
}
841
/* Starting a new process to be watched */
842
pid_t pid = fork();
843
if(pid == -1){
844
perror("fork");
845
exitstatus = EXIT_FAILURE;
846
goto fallback;
847
}
848
if(pid == 0){
849
/* this is the child process */
850
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
851
if(ret < 0){
852
perror("sigaction");
853
_exit(EXIT_FAILURE);
854
}
855
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
856
if(ret < 0){
857
perror("sigprocmask");
858
_exit(EXIT_FAILURE);
859
}
860
861
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
862
if(ret == -1){
863
perror("dup2");
864
_exit(EXIT_FAILURE);
865
}
866
867
if(dirfd(dir) < 0){
868
/* If dir has no file descriptor, we could not set FD_CLOEXEC
869
above and must now close it manually here. */
79
870
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;
114
}
871
}
872
if(p->environ[0] == NULL){
873
if(execv(filename, p->argv) < 0){
874
perror("execv");
875
_exit(EXIT_FAILURE);
876
}
877
} else {
878
if(execve(filename, p->argv, p->environ) < 0){
879
perror("execve");
880
_exit(EXIT_FAILURE);
881
}
882
}
883
/* no return */
884
}
885
/* Parent process */
886
close(pipefd[1]); /* Close unused write end of pipe */
887
free(filename);
888
plugin *new_plugin = getplugin(dirst->d_name);
889
if (new_plugin == NULL){
890
perror("getplugin");
891
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
892
if(ret < 0){
893
perror("sigprocmask");
894
}
895
exitstatus = EXIT_FAILURE;
896
goto fallback;
897
}
898
899
new_plugin->pid = pid;
900
new_plugin->fd = pipefd[0];
901
902
/* Unblock SIGCHLD so signal handler can be run if this process
903
has already completed */
904
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
905
if(ret < 0){
906
perror("sigprocmask");
907
exitstatus = EXIT_FAILURE;
908
goto fallback;
909
}
910
911
FD_SET(new_plugin->fd, &rfds_all);
912
913
if (maxfd < new_plugin->fd){
914
maxfd = new_plugin->fd;
915
}
916
115
917
}
116
918
117
919
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
}
920
dir = NULL;
921
922
for(plugin *p = plugin_list; p != NULL; p = p->next){
923
if(p->pid != 0){
178
924
break;
179
925
}
180
}
181
return EXIT_SUCCESS;
926
if(p->next == NULL){
927
fprintf(stderr, "No plugin processes started. Incorrect plugin"
928
" directory?\n");
929
free_plugin_list();
930
}
931
}
932
933
/* Main loop while running plugins exist */
934
while(plugin_list){
935
fd_set rfds = rfds_all;
936
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
937
if (select_ret == -1){
938
perror("select");
939
exitstatus = EXIT_FAILURE;
940
goto fallback;
941
}
942
/* OK, now either a process completed, or something can be read
943
from one of them */
944
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
945
/* Is this process completely done? */
946
if(proc->eof and proc->completed){
947
/* Only accept the plugin output if it exited cleanly */
948
if(not WIFEXITED(proc->status)
949
or WEXITSTATUS(proc->status) != 0){
950
/* Bad exit by plugin */
951
952
if(debug){
953
if(WIFEXITED(proc->status)){
954
fprintf(stderr, "Plugin %u exited with status %d\n",
955
(unsigned int) (proc->pid),
956
WEXITSTATUS(proc->status));
957
} else if(WIFSIGNALED(proc->status)) {
958
fprintf(stderr, "Plugin %u killed by signal %d\n",
959
(unsigned int) (proc->pid),
960
WTERMSIG(proc->status));
961
} else if(WCOREDUMP(proc->status)){
962
fprintf(stderr, "Plugin %d dumped core\n",
963
(unsigned int) (proc->pid));
964
}
965
}
966
967
/* Remove the plugin */
968
FD_CLR(proc->fd, &rfds_all);
969
970
/* Block signal while modifying process_list */
971
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
972
if(ret < 0){
973
perror("sigprocmask");
974
exitstatus = EXIT_FAILURE;
975
goto fallback;
976
}
977
free_plugin(proc);
978
/* We are done modifying process list, so unblock signal */
979
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
980
NULL);
981
if(ret < 0){
982
perror("sigprocmask");
983
exitstatus = EXIT_FAILURE;
984
goto fallback;
985
}
986
987
if(plugin_list == NULL){
988
break;
989
}
990
continue;
991
}
992
993
/* This process exited nicely, so print its buffer */
994
995
bool bret = print_out_password(proc->buffer,
996
proc->buffer_length);
997
if(not bret){
998
perror("print_out_password");
999
exitstatus = EXIT_FAILURE;
1000
}
1001
goto fallback;
1002
}
1003
1004
/* This process has not completed. Does it have any output? */
1005
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1006
/* This process had nothing to say at this time */
1007
continue;
1008
}
1009
/* Before reading, make the process' data buffer large enough */
1010
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1011
proc->buffer = realloc(proc->buffer, proc->buffer_size
1012
+ (size_t) BUFFER_SIZE);
1013
if (proc->buffer == NULL){
1014
perror("malloc");
1015
exitstatus = EXIT_FAILURE;
1016
goto fallback;
1017
}
1018
proc->buffer_size += BUFFER_SIZE;
1019
}
1020
/* Read from the process */
1021
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1022
BUFFER_SIZE);
1023
if(ret < 0){
1024
/* Read error from this process; ignore the error */
1025
continue;
1026
}
1027
if(ret == 0){
1028
/* got EOF */
1029
proc->eof = true;
1030
} else {
1031
proc->buffer_length += (size_t) ret;
1032
}
1033
}
1034
}
1035
1036
1037
fallback:
1038
1039
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1040
/* Fallback if all plugins failed, none are found or an error
1041
occured */
1042
bool bret;
1043
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1044
char *passwordbuffer = getpass("Password: ");
1045
size_t len = strlen(passwordbuffer);
1046
/* Strip trailing newline */
1047
if(len > 0 and passwordbuffer[len-1] == '\n'){
1048
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1049
len--;
1050
}
1051
bret = print_out_password(passwordbuffer, len);
1052
if(not bret){
1053
perror("print_out_password");
1054
exitstatus = EXIT_FAILURE;
1055
}
1056
}
1057
1058
/* Restore old signal handler */
1059
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1060
if(ret == -1){
1061
perror("sigaction");
1062
exitstatus = EXIT_FAILURE;
1063
}
1064
1065
if(custom_argv != NULL){
1066
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1067
free(*arg);
1068
}
1069
free(custom_argv);
1070
}
1071
1072
if(dir != NULL){
1073
closedir(dir);
1074
}
1075
1076
/* Free the process list and kill the processes */
1077
for(plugin *p = plugin_list; p != NULL; p = p->next){
1078
if(p->pid != 0){
1079
close(p->fd);
1080
ret = kill(p->pid, SIGTERM);
1081
if(ret == -1 and errno != ESRCH){
1082
/* Set-uid proccesses might not get closed */
1083
perror("kill");
1084
}
1085
}
1086
}
1087
1088
/* Wait for any remaining child processes to terminate */
1089
do{
1090
ret = wait(NULL);
1091
} while(ret >= 0);
1092
if(errno != ECHILD){
1093
perror("wait");
1094
}
1095
1096
free_plugin_list();
1097
1098
free(plugindir);
1099
free(argfile);
1100
1101
return exitstatus;
182
1102
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0