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- Committer: Teddy Hogeborn
- Date: 2009-10-22 00:05:01 UTC
- Revision ID: teddy@fukt.bsnet.se-20091022000501-g792e99q5g1wkyet
Merge from release branch.
- 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
/* -*- coding: utf-8 -*- */
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
2
2
/*
3
3
* Mandos plugin runner - Run Mandos plugins
4
4
*
5
* Copyright © 2007-2008 Teddy Hogeborn and Björn Påhlsson.
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
6
7
*
7
8
* This program is free software: you can redistribute it and/or
8
9
* modify it under the terms of the GNU General Public License as
18
19
* along with this program. If not, see
19
20
* <http://www.gnu.org/licenses/>.
20
21
*
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
23
*/
24
24
25
#define _FORTIFY_SOURCE 2
26
27
#include <stdio.h> /* popen, fileno */
28
#include <iso646.h> /* and, or, not */
29
#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
30
WIFEXITED, WEXITSTATUS, wait */
31
#include <sys/wait.h> /* wait */
32
#include <dirent.h> /* DIR, opendir */
33
#include <sys/stat.h> /* stat, struct stat */
34
#include <unistd.h> /* stat, struct stat, chdir */
35
#include <stdlib.h> /* EXIT_FAILURE */
36
#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET,
37
FD_ISSET */
38
#include <string.h> /* strlen, strcpy, strcat */
39
#include <stdbool.h> /* true */
40
#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
41
#include <errno.h> /* errno */
42
43
struct process;
44
45
typedef struct process{
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
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, fdopendir(), 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, fdopendir(),
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*/
46
89
pid_t pid;
47
90
int fd;
48
91
char *buffer;
49
92
size_t buffer_size;
50
93
size_t buffer_length;
51
struct process *next;
52
} process;
53
54
#define BUFFER_SIZE 256
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
}
55
326
56
327
int main(int argc, char *argv[]){
57
char plugindir[] = "plugins.d";
58
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
59
DIR *dir;
328
char *plugindir = NULL;
329
char *argfile = NULL;
330
FILE *conffp;
331
size_t d_name_len;
332
DIR *dir = NULL;
60
333
struct dirent *dirst;
61
334
struct stat st;
62
fd_set rfds_orig;
335
fd_set rfds_all;
63
336
int ret, maxfd = 0;
64
process *process_list = NULL;
65
66
dir = opendir(plugindir);
67
68
if(dir == NULL){
69
fprintf(stderr, "Can not open directory\n");
70
return EXIT_FAILURE;
71
}
72
73
FD_ZERO(&rfds_orig);
74
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
/* Open plugin directory with close_on_exec flag */
702
{
703
int dir_fd = -1;
704
if(plugindir == NULL){
705
dir_fd = open(PDIR, O_RDONLY |
706
#ifdef O_CLOEXEC
707
O_CLOEXEC
708
#else /* not O_CLOEXEC */
709
0
710
#endif /* not O_CLOEXEC */
711
);
712
} else {
713
dir_fd = open(plugindir, O_RDONLY |
714
#ifdef O_CLOEXEC
715
O_CLOEXEC
716
#else /* not O_CLOEXEC */
717
0
718
#endif /* not O_CLOEXEC */
719
);
720
}
721
if(dir_fd == -1){
722
perror("Could not open plugin dir");
723
exitstatus = EXIT_FAILURE;
724
goto fallback;
725
}
726
727
#ifndef O_CLOEXEC
728
/* Set the FD_CLOEXEC flag on the directory */
729
ret = set_cloexec_flag(dir_fd);
730
if(ret < 0){
731
perror("set_cloexec_flag");
732
TEMP_FAILURE_RETRY(close(dir_fd));
733
exitstatus = EXIT_FAILURE;
734
goto fallback;
735
}
736
#endif /* O_CLOEXEC */
737
738
dir = fdopendir(dir_fd);
739
if(dir == NULL){
740
perror("Could not open plugin dir");
741
TEMP_FAILURE_RETRY(close(dir_fd));
742
exitstatus = EXIT_FAILURE;
743
goto fallback;
744
}
745
}
746
747
FD_ZERO(&rfds_all);
748
749
/* Read and execute any executable in the plugin directory*/
75
750
while(true){
76
dirst = readdir(dir);
751
do {
752
dirst = readdir(dir);
753
} while(dirst == NULL and errno == EINTR);
77
754
78
// All directory entries have been processed
755
/* All directory entries have been processed */
79
756
if(dirst == NULL){
757
if(errno == EBADF){
758
perror("readdir");
759
exitstatus = EXIT_FAILURE;
760
goto fallback;
761
}
80
762
break;
81
763
}
82
764
83
765
d_name_len = strlen(dirst->d_name);
84
766
85
// Ignore dotfiles and backup files
86
if (dirst->d_name[0] == '.'
87
or dirst->d_name[d_name_len - 1] == '~'){
88
continue;
89
}
90
91
char *filename = malloc(d_name_len + plugindir_len + 2);
92
strcpy(filename, plugindir);
93
strcat(filename, "/");
94
strcat(filename, dirst->d_name);
95
96
stat(filename, &st);
97
98
if (S_ISREG(st.st_mode) and (access(filename, X_OK) == 0)){
99
// Starting a new process to be watched
100
process *new_process = malloc(sizeof(process));
101
int pipefd[2];
102
pipe(pipefd);
103
new_process->pid = fork();
104
if(new_process->pid == 0){
105
/* this is the child process */
767
/* Ignore dotfiles, backup files and other junk */
768
{
769
bool bad_name = false;
770
771
const char const *bad_prefixes[] = { ".", "#", NULL };
772
773
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
774
".dpkg-old",
775
".dpkg-bak",
776
".dpkg-divert", NULL };
777
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
778
size_t pre_len = strlen(*pre);
779
if((d_name_len >= pre_len)
780
and strncmp((dirst->d_name), *pre, pre_len) == 0){
781
if(debug){
782
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
783
" with bad prefix %s\n", dirst->d_name, *pre);
784
}
785
bad_name = true;
786
break;
787
}
788
}
789
if(bad_name){
790
continue;
791
}
792
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
793
size_t suf_len = strlen(*suf);
794
if((d_name_len >= suf_len)
795
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
796
== 0)){
797
if(debug){
798
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
799
" with bad suffix %s\n", dirst->d_name, *suf);
800
}
801
bad_name = true;
802
break;
803
}
804
}
805
806
if(bad_name){
807
continue;
808
}
809
}
810
811
char *filename;
812
if(plugindir == NULL){
813
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
814
dirst->d_name));
815
} else {
816
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
817
plugindir,
818
dirst->d_name));
819
}
820
if(ret < 0){
821
perror("asprintf");
822
continue;
823
}
824
825
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
826
if(ret == -1){
827
perror("stat");
828
free(filename);
829
continue;
830
}
831
832
/* Ignore non-executable files */
833
if(not S_ISREG(st.st_mode)
834
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
835
if(debug){
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
837
" with bad type or mode\n", filename);
838
}
839
free(filename);
840
continue;
841
}
842
843
plugin *p = getplugin(dirst->d_name);
844
if(p == NULL){
845
perror("getplugin");
846
free(filename);
847
continue;
848
}
849
if(p->disabled){
850
if(debug){
851
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
852
dirst->d_name);
853
}
854
free(filename);
855
continue;
856
}
857
{
858
/* Add global arguments to argument list for this plugin */
859
plugin *g = getplugin(NULL);
860
if(g != NULL){
861
for(char **a = g->argv + 1; *a != NULL; a++){
862
if(not add_argument(p, *a)){
863
perror("add_argument");
864
}
865
}
866
/* Add global environment variables */
867
for(char **e = g->environ; *e != NULL; e++){
868
if(not add_environment(p, *e, false)){
869
perror("add_environment");
870
}
871
}
872
}
873
}
874
/* If this plugin has any environment variables, we will call
875
using execve and need to duplicate the environment from this
876
process, too. */
877
if(p->environ[0] != NULL){
878
for(char **e = environ; *e != NULL; e++){
879
if(not add_environment(p, *e, false)){
880
perror("add_environment");
881
}
882
}
883
}
884
885
int pipefd[2];
886
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
887
if(ret == -1){
888
perror("pipe");
889
exitstatus = EXIT_FAILURE;
890
goto fallback;
891
}
892
/* Ask OS to automatic close the pipe on exec */
893
ret = set_cloexec_flag(pipefd[0]);
894
if(ret < 0){
895
perror("set_cloexec_flag");
896
exitstatus = EXIT_FAILURE;
897
goto fallback;
898
}
899
ret = set_cloexec_flag(pipefd[1]);
900
if(ret < 0){
901
perror("set_cloexec_flag");
902
exitstatus = EXIT_FAILURE;
903
goto fallback;
904
}
905
/* Block SIGCHLD until process is safely in process list */
906
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
907
&sigchld_action.sa_mask,
908
NULL));
909
if(ret < 0){
910
perror("sigprocmask");
911
exitstatus = EXIT_FAILURE;
912
goto fallback;
913
}
914
/* Starting a new process to be watched */
915
pid_t pid;
916
do {
917
pid = fork();
918
} while(pid == -1 and errno == EINTR);
919
if(pid == -1){
920
perror("fork");
921
exitstatus = EXIT_FAILURE;
922
goto fallback;
923
}
924
if(pid == 0){
925
/* this is the child process */
926
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
927
if(ret < 0){
928
perror("sigaction");
929
_exit(EXIT_FAILURE);
930
}
931
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
932
if(ret < 0){
933
perror("sigprocmask");
934
_exit(EXIT_FAILURE);
935
}
936
937
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
938
if(ret == -1){
939
perror("dup2");
940
_exit(EXIT_FAILURE);
941
}
942
943
if(dirfd(dir) < 0){
944
/* If dir has no file descriptor, we could not set FD_CLOEXEC
945
above and must now close it manually here. */
106
946
closedir(dir);
107
close(pipefd[0]); /* close unused read end of pipe */
108
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
109
/* create a new modified argument list */
110
char **new_argv = malloc(sizeof(char *)
111
* ((unsigned int) argc + 1));
112
new_argv[0] = filename;
113
for(int i = 1; i < argc; i++){
114
new_argv[i] = argv[i];
115
}
116
new_argv[argc] = NULL;
117
if(execv(filename, new_argv) < 0){
118
perror(argv[0]);
119
close(pipefd[1]);
120
exit(EXIT_FAILURE);
121
}
122
/* no return */
123
}
124
close(pipefd[1]); /* close unused write end of pipe */
125
new_process->fd = pipefd[0];
126
new_process->buffer = malloc(BUFFER_SIZE);
127
if (new_process->buffer == NULL){
128
perror(argv[0]);
129
goto end;
130
}
131
new_process->buffer_size = BUFFER_SIZE;
132
new_process->buffer_length = 0;
133
FD_SET(new_process->fd, &rfds_orig);
134
135
if (maxfd < new_process->fd){
136
maxfd = new_process->fd;
137
}
138
139
//List handling
140
new_process->next = process_list;
141
process_list = new_process;
142
}
143
}
144
145
closedir(dir);
146
147
if (process_list != NULL){
148
while(true){
149
fd_set rfds = rfds_orig;
150
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
151
if (select_ret == -1){
152
perror(argv[0]);
153
goto end;
154
}else{
155
for(process *process_itr = process_list; process_itr != NULL;
156
process_itr = process_itr->next){
157
if(FD_ISSET(process_itr->fd, &rfds)){
158
if(process_itr->buffer_length + BUFFER_SIZE
159
> process_itr->buffer_size){
160
process_itr->buffer = realloc(process_itr->buffer,
161
process_itr->buffer_size
162
+ (size_t) BUFFER_SIZE);
163
if (process_itr->buffer == NULL){
164
perror(argv[0]);
165
goto end;
166
}
167
process_itr->buffer_size += BUFFER_SIZE;
168
}
169
ret = read(process_itr->fd, process_itr->buffer
170
+ process_itr->buffer_length, BUFFER_SIZE);
171
if(ret < 0){
172
/* Read error from this process; ignore it */
173
continue;
174
}
175
process_itr->buffer_length += (size_t) ret;
176
if(ret == 0){
177
/* got EOF */
178
/* wait for process exit */
179
int status;
180
waitpid(process_itr->pid, &status, 0);
181
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
182
write(STDOUT_FILENO, process_itr->buffer,
183
process_itr->buffer_length);
184
goto end;
185
} else {
186
FD_CLR(process_itr->fd, &rfds_orig);
187
}
188
}
189
}
190
}
191
}
192
}
193
}
194
195
end:
196
for(process *process_itr = process_list; process_itr != NULL;
197
process_itr = process_itr->next){
198
close(process_itr->fd);
199
kill(process_itr->pid, SIGTERM);
200
free(process_itr->buffer);
201
}
202
203
while(true){
204
int status;
205
ret = wait(&status);
206
if (ret == -1){
207
if(errno != ECHILD){
208
perror("wait");
209
}
947
}
948
if(p->environ[0] == NULL){
949
if(execv(filename, p->argv) < 0){
950
perror("execv");
951
_exit(EXIT_FAILURE);
952
}
953
} else {
954
if(execve(filename, p->argv, p->environ) < 0){
955
perror("execve");
956
_exit(EXIT_FAILURE);
957
}
958
}
959
/* no return */
960
}
961
/* Parent process */
962
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
963
pipe */
964
free(filename);
965
plugin *new_plugin = getplugin(dirst->d_name);
966
if(new_plugin == NULL){
967
perror("getplugin");
968
ret = (int)(TEMP_FAILURE_RETRY
969
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
970
NULL)));
971
if(ret < 0){
972
perror("sigprocmask");
973
}
974
exitstatus = EXIT_FAILURE;
975
goto fallback;
976
}
977
978
new_plugin->pid = pid;
979
new_plugin->fd = pipefd[0];
980
981
/* Unblock SIGCHLD so signal handler can be run if this process
982
has already completed */
983
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
984
&sigchld_action.sa_mask,
985
NULL));
986
if(ret < 0){
987
perror("sigprocmask");
988
exitstatus = EXIT_FAILURE;
989
goto fallback;
990
}
991
992
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
993
-Wconversion */
994
995
if(maxfd < new_plugin->fd){
996
maxfd = new_plugin->fd;
997
}
998
}
999
1000
TEMP_FAILURE_RETRY(closedir(dir));
1001
dir = NULL;
1002
free_plugin(getplugin(NULL));
1003
1004
for(plugin *p = plugin_list; p != NULL; p = p->next){
1005
if(p->pid != 0){
210
1006
break;
211
1007
}
212
}
213
return EXIT_SUCCESS;
1008
if(p->next == NULL){
1009
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1010
" directory?\n");
1011
free_plugin_list();
1012
}
1013
}
1014
1015
/* Main loop while running plugins exist */
1016
while(plugin_list){
1017
fd_set rfds = rfds_all;
1018
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1019
if(select_ret == -1 and errno != EINTR){
1020
perror("select");
1021
exitstatus = EXIT_FAILURE;
1022
goto fallback;
1023
}
1024
/* OK, now either a process completed, or something can be read
1025
from one of them */
1026
for(plugin *proc = plugin_list; proc != NULL;){
1027
/* Is this process completely done? */
1028
if(proc->completed and proc->eof){
1029
/* Only accept the plugin output if it exited cleanly */
1030
if(not WIFEXITED(proc->status)
1031
or WEXITSTATUS(proc->status) != 0){
1032
/* Bad exit by plugin */
1033
1034
if(debug){
1035
if(WIFEXITED(proc->status)){
1036
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1037
" status %d\n", proc->name,
1038
(intmax_t) (proc->pid),
1039
WEXITSTATUS(proc->status));
1040
} else if(WIFSIGNALED(proc->status)){
1041
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1042
" signal %d: %s\n", proc->name,
1043
(intmax_t) (proc->pid),
1044
WTERMSIG(proc->status),
1045
strsignal(WTERMSIG(proc->status)));
1046
} else if(WCOREDUMP(proc->status)){
1047
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1048
" core\n", proc->name, (intmax_t) (proc->pid));
1049
}
1050
}
1051
1052
/* Remove the plugin */
1053
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1054
-Wconversion */
1055
1056
/* Block signal while modifying process_list */
1057
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1058
(SIG_BLOCK,
1059
&sigchld_action.sa_mask,
1060
NULL));
1061
if(ret < 0){
1062
perror("sigprocmask");
1063
exitstatus = EXIT_FAILURE;
1064
goto fallback;
1065
}
1066
1067
plugin *next_plugin = proc->next;
1068
free_plugin(proc);
1069
proc = next_plugin;
1070
1071
/* We are done modifying process list, so unblock signal */
1072
ret = (int)(TEMP_FAILURE_RETRY
1073
(sigprocmask(SIG_UNBLOCK,
1074
&sigchld_action.sa_mask, NULL)));
1075
if(ret < 0){
1076
perror("sigprocmask");
1077
exitstatus = EXIT_FAILURE;
1078
goto fallback;
1079
}
1080
1081
if(plugin_list == NULL){
1082
break;
1083
}
1084
1085
continue;
1086
}
1087
1088
/* This process exited nicely, so print its buffer */
1089
1090
bool bret = print_out_password(proc->buffer,
1091
proc->buffer_length);
1092
if(not bret){
1093
perror("print_out_password");
1094
exitstatus = EXIT_FAILURE;
1095
}
1096
goto fallback;
1097
}
1098
1099
/* This process has not completed. Does it have any output? */
1100
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1101
warning from
1102
-Wconversion */
1103
/* This process had nothing to say at this time */
1104
proc = proc->next;
1105
continue;
1106
}
1107
/* Before reading, make the process' data buffer large enough */
1108
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1109
proc->buffer = realloc(proc->buffer, proc->buffer_size
1110
+ (size_t) BUFFER_SIZE);
1111
if(proc->buffer == NULL){
1112
perror("malloc");
1113
exitstatus = EXIT_FAILURE;
1114
goto fallback;
1115
}
1116
proc->buffer_size += BUFFER_SIZE;
1117
}
1118
/* Read from the process */
1119
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1120
proc->buffer
1121
+ proc->buffer_length,
1122
BUFFER_SIZE));
1123
if(sret < 0){
1124
/* Read error from this process; ignore the error */
1125
proc = proc->next;
1126
continue;
1127
}
1128
if(sret == 0){
1129
/* got EOF */
1130
proc->eof = true;
1131
} else {
1132
proc->buffer_length += (size_t) sret;
1133
}
1134
}
1135
}
1136
1137
1138
fallback:
1139
1140
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1141
/* Fallback if all plugins failed, none are found or an error
1142
occured */
1143
bool bret;
1144
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1145
char *passwordbuffer = getpass("Password: ");
1146
size_t len = strlen(passwordbuffer);
1147
/* Strip trailing newline */
1148
if(len > 0 and passwordbuffer[len-1] == '\n'){
1149
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1150
len--;
1151
}
1152
bret = print_out_password(passwordbuffer, len);
1153
if(not bret){
1154
perror("print_out_password");
1155
exitstatus = EXIT_FAILURE;
1156
}
1157
}
1158
1159
/* Restore old signal handler */
1160
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1161
if(ret == -1){
1162
perror("sigaction");
1163
exitstatus = EXIT_FAILURE;
1164
}
1165
1166
if(custom_argv != NULL){
1167
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1168
free(*arg);
1169
}
1170
free(custom_argv);
1171
}
1172
1173
if(dir != NULL){
1174
closedir(dir);
1175
}
1176
1177
/* Kill the processes */
1178
for(plugin *p = plugin_list; p != NULL; p = p->next){
1179
if(p->pid != 0){
1180
close(p->fd);
1181
ret = kill(p->pid, SIGTERM);
1182
if(ret == -1 and errno != ESRCH){
1183
/* Set-uid proccesses might not get closed */
1184
perror("kill");
1185
}
1186
}
1187
}
1188
1189
/* Wait for any remaining child processes to terminate */
1190
do {
1191
ret = wait(NULL);
1192
} while(ret >= 0);
1193
if(errno != ECHILD){
1194
perror("wait");
1195
}
1196
1197
free_plugin_list();
1198
1199
free(plugindir);
1200
free(argfile);
1201
1202
return exitstatus;
214
1203
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0