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