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- Committer: Teddy Hogeborn
- Date: 2008-09-01 08:29:23 UTC
- Revision ID: teddy@fukt.bsnet.se-20080901082923-i2liq6t7warmu9xe
* mandos.xml: Enclose "RAM" with <acronym>.
* overview.xml: - '' -
* plugin-runner.xml (DESCRIPTION): Improved wording.
(PURPOSE): New section.
(OPTIONS): Improved wording.
(OVERVIEW, PLUGINS): New section.
(FALLBACK): New empty placeholder section.
* plugins.d/password-prompt.xml: Enclose "RAM" with <acronym>.
* overview.xml: - '' -
* plugin-runner.xml (DESCRIPTION): Improved wording.
(PURPOSE): New section.
(OPTIONS): Improved wording.
(OVERVIEW, PLUGINS): New section.
(FALLBACK): New empty placeholder section.
* plugins.d/password-prompt.xml: Enclose "RAM" with <acronym>.
- files added:
- .bzrignore
- plugins.d
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- files modified:
- Makefile
added
removed
plugin-runner.c
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
6
*
7
* This program is free software: you can redistribute it and/or
8
* modify it under the terms of the GNU General Public License as
9
* published by the Free Software Foundation, either version 3 of the
10
* License, or (at your option) any later version.
11
*
12
* This program is distributed in the hope that it will be useful, but
13
* WITHOUT ANY WARRANTY; without even the implied warranty of
14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15
* General Public License for more details.
16
*
17
* You should have received a copy of the GNU General Public License
18
* along with this program. If not, see
19
* <http://www.gnu.org/licenses/>.
20
*
21
* Contact the authors at <mandos@fukt.bsnet.se>.
22
*/
23
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
25
asprintf() */
26
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
stat, waitpid(), WIFEXITED(),
34
WEXITSTATUS(), wait(), pid_t,
35
uid_t, gid_t, getuid(), getgid(),
36
dirfd() */
37
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
FD_SET(), FD_ISSET(), FD_CLR */
39
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
40
WEXITSTATUS() */
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
44
readdir(), closedir(), dirfd() */
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
46
fcntl(), setuid(), setgid(),
47
F_GETFD, F_SETFD, FD_CLOEXEC,
48
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
50
execv(), write(), read(),
51
close() */
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC */
54
#include <string.h> /* strsep, strlen(), asprintf() */
55
#include <errno.h> /* errno */
56
#include <argp.h> /* struct argp_option, struct
57
argp_state, struct argp,
58
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG,
60
error_t */
61
#include <signal.h> /* struct sigaction, sigemptyset(),
62
sigaddset(), sigaction(),
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
#include <errno.h> /* errno, EBADF */
66
67
#define BUFFER_SIZE 256
68
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
71
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
75
struct plugin;
76
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
79
char **argv;
80
int argc;
81
char **environ;
82
int envc;
83
bool disabled;
84
85
/* Variables used for running processes*/
86
pid_t pid;
87
int fd;
88
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 a existing plugin based on name,
100
or if none is found, creates a new one */
101
static plugin *getplugin(char *name){
102
/* Check for exiting plugin with that name */
103
for (plugin *p = plugin_list; p != NULL; p = p->next){
104
if ((p->name == name)
105
or (p->name and name and (strcmp(p->name, name) == 0))){
106
return p;
107
}
108
}
109
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if (new_plugin == NULL){
112
return NULL;
113
}
114
char *copy_name = NULL;
115
if(name != NULL){
116
copy_name = strdup(name);
117
if(copy_name == NULL){
118
return NULL;
119
}
120
}
121
122
*new_plugin = (plugin) { .name = copy_name,
123
.argc = 1,
124
.disabled = false,
125
.next = plugin_list };
126
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
129
free(copy_name);
130
free(new_plugin);
131
return NULL;
132
}
133
new_plugin->argv[0] = copy_name;
134
new_plugin->argv[1] = NULL;
135
136
new_plugin->environ = malloc(sizeof(char *));
137
if(new_plugin->environ == NULL){
138
free(copy_name);
139
free(new_plugin->argv);
140
free(new_plugin);
141
return NULL;
142
}
143
new_plugin->environ[0] = NULL;
144
145
/* Append the new plugin to the list */
146
plugin_list = new_plugin;
147
return new_plugin;
148
}
149
150
/* Helper function for add_argument and add_environment */
151
static bool add_to_char_array(const char *new, char ***array,
152
int *len){
153
/* Resize the pointed-to array to hold one more pointer */
154
*array = realloc(*array, sizeof(char *)
155
* (size_t) ((*len) + 2));
156
/* Malloc check */
157
if(*array == NULL){
158
return false;
159
}
160
/* Make a copy of the new string */
161
char *copy = strdup(new);
162
if(copy == NULL){
163
return false;
164
}
165
/* Insert the copy */
166
(*array)[*len] = copy;
167
(*len)++;
168
/* Add a new terminating NULL pointer to the last element */
169
(*array)[*len] = NULL;
170
return true;
171
}
172
173
/* Add to a plugin's argument vector */
174
static bool add_argument(plugin *p, const char *arg){
175
if(p == NULL){
176
return false;
177
}
178
return add_to_char_array(arg, &(p->argv), &(p->argc));
179
}
180
181
/* Add to a plugin's environment */
182
static bool add_environment(plugin *p, const char *def){
183
if(p == NULL){
184
return false;
185
}
186
return add_to_char_array(def, &(p->environ), &(p->envc));
187
}
188
189
/*
190
* Based on the example in the GNU LibC manual chapter 13.13 "File
191
* Descriptor Flags".
192
* *Note File Descriptor Flags:(libc)Descriptor Flags.
193
*/
194
static int set_cloexec_flag(int fd)
195
{
196
int ret = fcntl(fd, F_GETFD, 0);
197
/* If reading the flags failed, return error indication now. */
198
if(ret < 0){
199
return ret;
200
}
201
/* Store modified flag word in the descriptor. */
202
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
203
}
204
205
206
/* Mark processes as completed when they exit, and save their exit
207
status. */
208
void handle_sigchld(__attribute__((unused)) int sig){
209
while(true){
210
plugin *proc = plugin_list;
211
int status;
212
pid_t pid = waitpid(-1, &status, WNOHANG);
213
if(pid == 0){
214
/* Only still running child processes */
215
break;
216
}
217
if(pid == -1){
218
if (errno != ECHILD){
219
perror("waitpid");
220
}
221
/* No child processes */
222
break;
223
}
224
225
/* A child exited, find it in process_list */
226
while(proc != NULL and proc->pid != pid){
227
proc = proc->next;
228
}
229
if(proc == NULL){
230
/* Process not found in process list */
231
continue;
232
}
233
proc->status = status;
234
proc->completed = true;
235
}
236
}
237
238
/* Prints out a password to stdout */
239
bool print_out_password(const char *buffer, size_t length){
240
ssize_t ret;
241
if(length>0 and buffer[length-1] == '\n'){
242
length--;
243
}
244
for(size_t written = 0; written < length; written += (size_t)ret){
245
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
246
length - written));
247
if(ret < 0){
248
return false;
249
}
250
}
251
return true;
252
}
253
254
/* Removes and free a plugin from the plugin list */
255
static void free_plugin(plugin *plugin_node){
256
257
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
258
free(*arg);
259
}
260
free(plugin_node->argv);
261
for(char **env = plugin_node->environ; *env != NULL; env++){
262
free(*env);
263
}
264
free(plugin_node->environ);
265
free(plugin_node->buffer);
266
267
/* Removes the plugin from the singly-linked list */
268
if(plugin_node == plugin_list){
269
/* First one - simple */
270
plugin_list = plugin_list->next;
271
} else {
272
/* Second one or later */
273
for(plugin *p = plugin_list; p != NULL; p = p->next){
274
if(p->next == plugin_node){
275
p->next = plugin_node->next;
276
break;
277
}
278
}
279
}
280
281
free(plugin_node);
282
}
283
284
static void free_plugin_list(void){
285
while(plugin_list != NULL){
286
free_plugin(plugin_list);
287
}
288
}
289
290
int main(int argc, char *argv[]){
291
char *plugindir = NULL;
292
char *argfile = NULL;
293
FILE *conffp;
294
size_t d_name_len;
295
DIR *dir = NULL;
296
struct dirent *dirst;
297
struct stat st;
298
fd_set rfds_all;
299
int ret, maxfd = 0;
300
uid_t uid = 65534;
301
gid_t gid = 65534;
302
bool debug = false;
303
int exitstatus = EXIT_SUCCESS;
304
struct sigaction old_sigchld_action;
305
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
306
.sa_flags = SA_NOCLDSTOP };
307
char **custom_argv = NULL;
308
int custom_argc = 0;
309
310
/* Establish a signal handler */
311
sigemptyset(&sigchld_action.sa_mask);
312
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
313
if(ret == -1){
314
perror("sigaddset");
315
exitstatus = EXIT_FAILURE;
316
goto fallback;
317
}
318
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
319
if(ret == -1){
320
perror("sigaction");
321
exitstatus = EXIT_FAILURE;
322
goto fallback;
323
}
324
325
/* The options we understand. */
326
struct argp_option options[] = {
327
{ .name = "global-options", .key = 'g',
328
.arg = "OPTION[,OPTION[,...]]",
329
.doc = "Options passed to all plugins" },
330
{ .name = "global-envs", .key = 'e',
331
.arg = "VAR=value",
332
.doc = "Environment variable passed to all plugins" },
333
{ .name = "options-for", .key = 'o',
334
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
335
.doc = "Options passed only to specified plugin" },
336
{ .name = "envs-for", .key = 'f',
337
.arg = "PLUGIN:ENV=value",
338
.doc = "Environment variable passed to specified plugin" },
339
{ .name = "disable", .key = 'd',
340
.arg = "PLUGIN",
341
.doc = "Disable a specific plugin", .group = 1 },
342
{ .name = "plugin-dir", .key = 128,
343
.arg = "DIRECTORY",
344
.doc = "Specify a different plugin directory", .group = 2 },
345
{ .name = "config-file", .key = 129,
346
.arg = "FILE",
347
.doc = "Specify a different configuration file", .group = 2 },
348
{ .name = "userid", .key = 130,
349
.arg = "ID", .flags = 0,
350
.doc = "User ID the plugins will run as", .group = 3 },
351
{ .name = "groupid", .key = 131,
352
.arg = "ID", .flags = 0,
353
.doc = "Group ID the plugins will run as", .group = 3 },
354
{ .name = "debug", .key = 132,
355
.doc = "Debug mode", .group = 4 },
356
{ .name = NULL }
357
};
358
359
error_t parse_opt (int key, char *arg, __attribute__((unused))
360
struct argp_state *state) {
361
/* Get the INPUT argument from `argp_parse', which we know is a
362
pointer to our plugin list pointer. */
363
switch (key) {
364
case 'g': /* --global-options */
365
if (arg != NULL){
366
char *p;
367
while((p = strsep(&arg, ",")) != NULL){
368
if(p[0] == '\0'){
369
continue;
370
}
371
if(not add_argument(getplugin(NULL), p)){
372
perror("add_argument");
373
return ARGP_ERR_UNKNOWN;
374
}
375
}
376
}
377
break;
378
case 'e': /* --global-envs */
379
if(arg == NULL){
380
break;
381
}
382
{
383
char *envdef = strdup(arg);
384
if(envdef == NULL){
385
break;
386
}
387
if(not add_environment(getplugin(NULL), envdef)){
388
perror("add_environment");
389
}
390
}
391
break;
392
case 'o': /* --options-for */
393
if (arg != NULL){
394
char *p_name = strsep(&arg, ":");
395
if(p_name[0] == '\0'){
396
break;
397
}
398
char *opt = strsep(&arg, ":");
399
if(opt[0] == '\0'){
400
break;
401
}
402
if(opt != NULL){
403
char *p;
404
while((p = strsep(&opt, ",")) != NULL){
405
if(p[0] == '\0'){
406
continue;
407
}
408
if(not add_argument(getplugin(p_name), p)){
409
perror("add_argument");
410
return ARGP_ERR_UNKNOWN;
411
}
412
}
413
}
414
}
415
break;
416
case 'f': /* --envs-for */
417
if(arg == NULL){
418
break;
419
}
420
{
421
char *envdef = strchr(arg, ':');
422
if(envdef == NULL){
423
break;
424
}
425
char *p_name = strndup(arg, (size_t) (envdef-arg));
426
if(p_name == NULL){
427
break;
428
}
429
envdef++;
430
if(not add_environment(getplugin(p_name), envdef)){
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 128: /* --plugin-dir */
445
plugindir = strdup(arg);
446
if(plugindir == NULL){
447
perror("strdup");
448
}
449
break;
450
case 129: /* --config-file */
451
argfile = strdup(arg);
452
if(argfile == NULL){
453
perror("strdup");
454
}
455
break;
456
case 130: /* --userid */
457
uid = (uid_t)strtol(arg, NULL, 10);
458
break;
459
case 131: /* --groupid */
460
gid = (gid_t)strtol(arg, NULL, 10);
461
break;
462
case 132: /* --debug */
463
debug = true;
464
break;
465
case ARGP_KEY_ARG:
466
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
467
break;
468
case ARGP_KEY_END:
469
break;
470
default:
471
return ARGP_ERR_UNKNOWN;
472
}
473
return 0;
474
}
475
476
struct argp argp = { .options = options, .parser = parse_opt,
477
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
478
.doc = "Mandos plugin runner -- Run plugins" };
479
480
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
481
if (ret == ARGP_ERR_UNKNOWN){
482
fprintf(stderr, "Unknown error while parsing arguments\n");
483
exitstatus = EXIT_FAILURE;
484
goto fallback;
485
}
486
487
/* Opens the configfile if aviable */
488
if (argfile == NULL){
489
conffp = fopen(AFILE, "r");
490
} else {
491
conffp = fopen(argfile, "r");
492
}
493
if(conffp != NULL){
494
char *org_line = NULL;
495
char *p, *arg, *new_arg, *line;
496
size_t size = 0;
497
ssize_t sret;
498
const char whitespace_delims[] = " \r\t\f\v\n";
499
const char comment_delim[] = "#";
500
501
custom_argc = 1;
502
custom_argv = malloc(sizeof(char*) * 2);
503
if(custom_argv == NULL){
504
perror("malloc");
505
exitstatus = EXIT_FAILURE;
506
goto fallback;
507
}
508
custom_argv[0] = argv[0];
509
custom_argv[1] = NULL;
510
511
/* for each line in the config file, strip whitespace and ignore
512
commented text */
513
while(true){
514
sret = getline(&org_line, &size, conffp);
515
if(sret == -1){
516
break;
517
}
518
519
line = org_line;
520
arg = strsep(&line, comment_delim);
521
while((p = strsep(&arg, whitespace_delims)) != NULL){
522
if(p[0] == '\0'){
523
continue;
524
}
525
new_arg = strdup(p);
526
if(new_arg == NULL){
527
perror("strdup");
528
exitstatus = EXIT_FAILURE;
529
free(org_line);
530
goto fallback;
531
}
532
533
custom_argc += 1;
534
custom_argv = realloc(custom_argv, sizeof(char *)
535
* ((unsigned int) custom_argc + 1));
536
if(custom_argv == NULL){
537
perror("realloc");
538
exitstatus = EXIT_FAILURE;
539
free(org_line);
540
goto fallback;
541
}
542
custom_argv[custom_argc-1] = new_arg;
543
custom_argv[custom_argc] = NULL;
544
}
545
}
546
free(org_line);
547
} else{
548
/* Check for harmful errors and go to fallback. Other errors might
549
not affect opening plugins */
550
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
551
perror("fopen");
552
exitstatus = EXIT_FAILURE;
553
goto fallback;
554
}
555
}
556
/* If there was any arguments from configuration file,
557
pass them to parser as command arguments */
558
if(custom_argv != NULL){
559
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, NULL);
560
if (ret == ARGP_ERR_UNKNOWN){
561
fprintf(stderr, "Unknown error while parsing arguments\n");
562
exitstatus = EXIT_FAILURE;
563
goto fallback;
564
}
565
}
566
567
if(debug){
568
for(plugin *p = plugin_list; p != NULL; p=p->next){
569
fprintf(stderr, "Plugin: %s has %d arguments\n",
570
p->name ? p->name : "Global", p->argc - 1);
571
for(char **a = p->argv; *a != NULL; a++){
572
fprintf(stderr, "\tArg: %s\n", *a);
573
}
574
fprintf(stderr, "...and %u environment variables\n", p->envc);
575
for(char **a = p->environ; *a != NULL; a++){
576
fprintf(stderr, "\t%s\n", *a);
577
}
578
}
579
}
580
581
/* Strip permissions down to nobody */
582
ret = setuid(uid);
583
if (ret == -1){
584
perror("setuid");
585
}
586
setgid(gid);
587
if (ret == -1){
588
perror("setgid");
589
}
590
591
if (plugindir == NULL){
592
dir = opendir(PDIR);
593
} else {
594
dir = opendir(plugindir);
595
}
596
597
if(dir == NULL){
598
perror("Could not open plugin dir");
599
exitstatus = EXIT_FAILURE;
600
goto fallback;
601
}
602
603
/* Set the FD_CLOEXEC flag on the directory, if possible */
604
{
605
int dir_fd = dirfd(dir);
606
if(dir_fd >= 0){
607
ret = set_cloexec_flag(dir_fd);
608
if(ret < 0){
609
perror("set_cloexec_flag");
610
exitstatus = EXIT_FAILURE;
611
goto fallback;
612
}
613
}
614
}
615
616
FD_ZERO(&rfds_all);
617
618
/* Read and execute any executable in the plugin directory*/
619
while(true){
620
dirst = readdir(dir);
621
622
// All directory entries have been processed
623
if(dirst == NULL){
624
if (errno == EBADF){
625
perror("readdir");
626
exitstatus = EXIT_FAILURE;
627
goto fallback;
628
}
629
break;
630
}
631
632
d_name_len = strlen(dirst->d_name);
633
634
// Ignore dotfiles, backup files and other junk
635
{
636
bool bad_name = false;
637
638
const char const *bad_prefixes[] = { ".", "#", NULL };
639
640
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
641
".dpkg-old",
642
".dpkg-divert", NULL };
643
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
644
size_t pre_len = strlen(*pre);
645
if((d_name_len >= pre_len)
646
and strncmp((dirst->d_name), *pre, pre_len) == 0){
647
if(debug){
648
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
649
" with bad prefix %s\n", dirst->d_name, *pre);
650
}
651
bad_name = true;
652
break;
653
}
654
}
655
if(bad_name){
656
continue;
657
}
658
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
659
size_t suf_len = strlen(*suf);
660
if((d_name_len >= suf_len)
661
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
662
== 0)){
663
if(debug){
664
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
665
" with bad suffix %s\n", dirst->d_name, *suf);
666
}
667
bad_name = true;
668
break;
669
}
670
}
671
672
if(bad_name){
673
continue;
674
}
675
}
676
677
char *filename;
678
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
679
if(ret < 0){
680
perror("asprintf");
681
continue;
682
}
683
684
ret = stat(filename, &st);
685
if (ret == -1){
686
perror("stat");
687
free(filename);
688
continue;
689
}
690
691
/* Ignore non-executable files */
692
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
693
if(debug){
694
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
695
" with bad type or mode\n", filename);
696
}
697
free(filename);
698
continue;
699
}
700
701
plugin *p = getplugin(dirst->d_name);
702
if(p == NULL){
703
perror("getplugin");
704
free(filename);
705
continue;
706
}
707
if(p->disabled){
708
if(debug){
709
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
710
dirst->d_name);
711
}
712
free(filename);
713
continue;
714
}
715
{
716
/* Add global arguments to argument list for this plugin */
717
plugin *g = getplugin(NULL);
718
if(g != NULL){
719
for(char **a = g->argv + 1; *a != NULL; a++){
720
if(not add_argument(p, *a)){
721
perror("add_argument");
722
}
723
}
724
/* Add global environment variables */
725
for(char **e = g->environ; *e != NULL; e++){
726
if(not add_environment(p, *e)){
727
perror("add_environment");
728
}
729
}
730
}
731
}
732
/* If this plugin has any environment variables, we will call
733
using execve and need to duplicate the environment from this
734
process, too. */
735
if(p->environ[0] != NULL){
736
for(char **e = environ; *e != NULL; e++){
737
char *copy = strdup(*e);
738
if(copy == NULL){
739
perror("strdup");
740
continue;
741
}
742
if(not add_environment(p, copy)){
743
perror("add_environment");
744
}
745
}
746
}
747
748
int pipefd[2];
749
ret = pipe(pipefd);
750
if (ret == -1){
751
perror("pipe");
752
exitstatus = EXIT_FAILURE;
753
goto fallback;
754
}
755
/* Ask OS to automatic close the pipe on exec */
756
ret = set_cloexec_flag(pipefd[0]);
757
if(ret < 0){
758
perror("set_cloexec_flag");
759
exitstatus = EXIT_FAILURE;
760
goto fallback;
761
}
762
ret = set_cloexec_flag(pipefd[1]);
763
if(ret < 0){
764
perror("set_cloexec_flag");
765
exitstatus = EXIT_FAILURE;
766
goto fallback;
767
}
768
/* Block SIGCHLD until process is safely in process list */
769
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
770
if(ret < 0){
771
perror("sigprocmask");
772
exitstatus = EXIT_FAILURE;
773
goto fallback;
774
}
775
// Starting a new process to be watched
776
pid_t pid = fork();
777
if(pid == -1){
778
perror("fork");
779
exitstatus = EXIT_FAILURE;
780
goto fallback;
781
}
782
if(pid == 0){
783
/* this is the child process */
784
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
785
if(ret < 0){
786
perror("sigaction");
787
_exit(EXIT_FAILURE);
788
}
789
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
790
if(ret < 0){
791
perror("sigprocmask");
792
_exit(EXIT_FAILURE);
793
}
794
795
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
796
if(ret == -1){
797
perror("dup2");
798
_exit(EXIT_FAILURE);
799
}
800
801
if(dirfd(dir) < 0){
802
/* If dir has no file descriptor, we could not set FD_CLOEXEC
803
above and must now close it manually here. */
804
closedir(dir);
805
}
806
if(p->environ[0] == NULL){
807
if(execv(filename, p->argv) < 0){
808
perror("execv");
809
_exit(EXIT_FAILURE);
810
}
811
} else {
812
if(execve(filename, p->argv, p->environ) < 0){
813
perror("execve");
814
_exit(EXIT_FAILURE);
815
}
816
}
817
/* no return */
818
}
819
/* Parent process */
820
close(pipefd[1]); /* Close unused write end of pipe */
821
free(filename);
822
plugin *new_plugin = getplugin(dirst->d_name);
823
if (new_plugin == NULL){
824
perror("getplugin");
825
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
826
if(ret < 0){
827
perror("sigprocmask");
828
}
829
exitstatus = EXIT_FAILURE;
830
goto fallback;
831
}
832
833
new_plugin->pid = pid;
834
new_plugin->fd = pipefd[0];
835
836
/* Unblock SIGCHLD so signal handler can be run if this process
837
has already completed */
838
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
839
if(ret < 0){
840
perror("sigprocmask");
841
exitstatus = EXIT_FAILURE;
842
goto fallback;
843
}
844
845
FD_SET(new_plugin->fd, &rfds_all);
846
847
if (maxfd < new_plugin->fd){
848
maxfd = new_plugin->fd;
849
}
850
851
}
852
853
closedir(dir);
854
dir = NULL;
855
856
for(plugin *p = plugin_list; p != NULL; p = p->next){
857
if(p->pid != 0){
858
break;
859
}
860
if(p->next == NULL){
861
fprintf(stderr, "No plugin processes started. Incorrect plugin"
862
" directory?\n");
863
free_plugin_list();
864
}
865
}
866
867
/* Main loop while running plugins exist */
868
while(plugin_list){
869
fd_set rfds = rfds_all;
870
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
871
if (select_ret == -1){
872
perror("select");
873
exitstatus = EXIT_FAILURE;
874
goto fallback;
875
}
876
/* OK, now either a process completed, or something can be read
877
from one of them */
878
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
879
/* Is this process completely done? */
880
if(proc->eof and proc->completed){
881
/* Only accept the plugin output if it exited cleanly */
882
if(not WIFEXITED(proc->status)
883
or WEXITSTATUS(proc->status) != 0){
884
/* Bad exit by plugin */
885
886
if(debug){
887
if(WIFEXITED(proc->status)){
888
fprintf(stderr, "Plugin %u exited with status %d\n",
889
(unsigned int) (proc->pid),
890
WEXITSTATUS(proc->status));
891
} else if(WIFSIGNALED(proc->status)) {
892
fprintf(stderr, "Plugin %u killed by signal %d\n",
893
(unsigned int) (proc->pid),
894
WTERMSIG(proc->status));
895
} else if(WCOREDUMP(proc->status)){
896
fprintf(stderr, "Plugin %d dumped core\n",
897
(unsigned int) (proc->pid));
898
}
899
}
900
901
/* Remove the plugin */
902
FD_CLR(proc->fd, &rfds_all);
903
904
/* Block signal while modifying process_list */
905
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
906
if(ret < 0){
907
perror("sigprocmask");
908
exitstatus = EXIT_FAILURE;
909
goto fallback;
910
}
911
free_plugin(proc);
912
/* We are done modifying process list, so unblock signal */
913
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
914
NULL);
915
if(ret < 0){
916
perror("sigprocmask");
917
exitstatus = EXIT_FAILURE;
918
goto fallback;
919
}
920
921
if(plugin_list == NULL){
922
break;
923
}
924
continue;
925
}
926
927
/* This process exited nicely, so print its buffer */
928
929
bool bret = print_out_password(proc->buffer,
930
proc->buffer_length);
931
if(not bret){
932
perror("print_out_password");
933
exitstatus = EXIT_FAILURE;
934
}
935
goto fallback;
936
}
937
938
/* This process has not completed. Does it have any output? */
939
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
940
/* This process had nothing to say at this time */
941
continue;
942
}
943
/* Before reading, make the process' data buffer large enough */
944
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
945
proc->buffer = realloc(proc->buffer, proc->buffer_size
946
+ (size_t) BUFFER_SIZE);
947
if (proc->buffer == NULL){
948
perror("malloc");
949
exitstatus = EXIT_FAILURE;
950
goto fallback;
951
}
952
proc->buffer_size += BUFFER_SIZE;
953
}
954
/* Read from the process */
955
ret = read(proc->fd, proc->buffer + proc->buffer_length,
956
BUFFER_SIZE);
957
if(ret < 0){
958
/* Read error from this process; ignore the error */
959
continue;
960
}
961
if(ret == 0){
962
/* got EOF */
963
proc->eof = true;
964
} else {
965
proc->buffer_length += (size_t) ret;
966
}
967
}
968
}
969
970
971
fallback:
972
973
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
974
/* Fallback if all plugins failed, none are found or an error
975
occured */
976
bool bret;
977
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
978
char *passwordbuffer = getpass("Password: ");
979
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
980
if(not bret){
981
perror("print_out_password");
982
exitstatus = EXIT_FAILURE;
983
}
984
}
985
986
/* Restore old signal handler */
987
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
988
if(ret == -1){
989
perror("sigaction");
990
exitstatus = EXIT_FAILURE;
991
}
992
993
if(custom_argv != NULL){
994
for(char **arg = custom_argv+1; *arg != NULL; arg++){
995
free(*arg);
996
}
997
free(custom_argv);
998
}
999
1000
if(dir != NULL){
1001
closedir(dir);
1002
}
1003
1004
/* Free the process list and kill the processes */
1005
for(plugin *p = plugin_list; p != NULL; p = p->next){
1006
if(p->pid != 0){
1007
close(p->fd);
1008
ret = kill(p->pid, SIGTERM);
1009
if(ret == -1 and errno != ESRCH){
1010
/* Set-uid proccesses might not get closed */
1011
perror("kill");
1012
}
1013
}
1014
}
1015
1016
/* Wait for any remaining child processes to terminate */
1017
do{
1018
ret = wait(NULL);
1019
} while(ret >= 0);
1020
if(errno != ECHILD){
1021
perror("wait");
1022
}
1023
1024
free_plugin_list();
1025
1026
free(plugindir);
1027
free(argfile);
1028
1029
return exitstatus;
1030
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0