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