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- Committer: Teddy Hogeborn
- Date: 2008-08-19 13:25:14 UTC
- Revision ID: teddy@fukt.bsnet.se-20080819132514-wawrvgmfjovg9poj
* Makefile (DOCBOOKTOMAN): Added "--xinclude".
* mandos-options.xml: New file; moved mandos(8) option descriptions
here.
* mandos.conf.xml: Add XInclude namespace.
(OPTIONS): New separate section with options from old "DESCRIPTION"
section. Changed all options to include a synopsis and
include its paragraph from "mandos-options.xml".
(FILES): Moved to before "EXAMPLES".
(BUGS): New section.
(EXAMPLES): Renamed to "EXAMPLE", as per man-pages(7). Unindented
example text.
* mandos.xml: Removed OVERVIEW entity. Add XInclude namespace.
(OPTIONS): Moved all descriptive paragraphs to "mandos-options.xml"
and just <xi:include/> them from here.
(OVERVIEW): Changed to do <xi:include/>.
* overview.xml: Added DOCTYPE; reportedly needed for XInclude to work.
* mandos-options.xml: New file; moved mandos(8) option descriptions
here.
* mandos.conf.xml: Add XInclude namespace.
(OPTIONS): New separate section with options from old "DESCRIPTION"
section. Changed all options to include a synopsis and
include its paragraph from "mandos-options.xml".
(FILES): Moved to before "EXAMPLES".
(BUGS): New section.
(EXAMPLES): Renamed to "EXAMPLE", as per man-pages(7). Unindented
example text.
* mandos.xml: Removed OVERVIEW entity. Add XInclude namespace.
(OPTIONS): Moved all descriptive paragraphs to "mandos-options.xml"
and just <xi:include/> them from here.
(OVERVIEW): Changed to do <xi:include/>.
* overview.xml: Added DOCTYPE; reportedly needed for XInclude to work.
- files added:
- COPYING
- 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, error_t */
60
#include <signal.h> /* struct sigaction, sigemptyset(),
61
sigaddset(), sigaction(),
62
sigprocmask(), SIG_BLOCK, SIGCHLD,
63
SIG_UNBLOCK, kill() */
64
#include <errno.h> /* errno, EBADF */
65
66
#define BUFFER_SIZE 256
67
#define ARGFILE "/conf/conf.d/mandos/plugin-runner.conf"
68
69
const char *argp_program_version = "plugin-runner 1.0";
70
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
71
72
struct process;
73
74
typedef struct process{
75
pid_t pid;
76
int fd;
77
char *buffer;
78
size_t buffer_size;
79
size_t buffer_length;
80
bool eof;
81
bool completed;
82
int status;
83
struct process *next;
84
} process;
85
86
typedef struct plugin{
87
char *name; /* can be NULL or any plugin name */
88
char **argv;
89
int argc;
90
char **environ;
91
int envc;
92
bool disabled;
93
struct plugin *next;
94
} plugin;
95
96
static plugin *getplugin(char *name, plugin **plugin_list){
97
for (plugin *p = *plugin_list; p != NULL; p = p->next){
98
if ((p->name == name)
99
or (p->name and name and (strcmp(p->name, name) == 0))){
100
return p;
101
}
102
}
103
/* Create a new plugin */
104
plugin *new_plugin = malloc(sizeof(plugin));
105
if (new_plugin == NULL){
106
return NULL;
107
}
108
char *copy_name = strdup(name);
109
if(copy_name == NULL){
110
return NULL;
111
}
112
113
*new_plugin = (plugin) { .name = copy_name,
114
.argc = 1,
115
.envc = 0,
116
.disabled = false,
117
.next = *plugin_list };
118
119
new_plugin->argv = malloc(sizeof(char *) * 2);
120
if (new_plugin->argv == NULL){
121
free(new_plugin);
122
return NULL;
123
}
124
new_plugin->argv[0] = copy_name;
125
new_plugin->argv[1] = NULL;
126
127
new_plugin->environ = malloc(sizeof(char *));
128
if(new_plugin->environ == NULL){
129
free(new_plugin->argv);
130
free(new_plugin);
131
return NULL;
132
}
133
new_plugin->environ[0] = NULL;
134
/* Append the new plugin to the list */
135
*plugin_list = new_plugin;
136
return new_plugin;
137
}
138
139
/* Helper function for add_argument and add_environment */
140
static bool add_to_char_array(const char *new, char ***array,
141
int *len){
142
/* Resize the pointed-to array to hold one more pointer */
143
*array = realloc(*array, sizeof(char *)
144
* (size_t) ((*len) + 2));
145
/* Malloc check */
146
if(*array == NULL){
147
return false;
148
}
149
/* Make a copy of the new string */
150
char *copy = strdup(new);
151
if(copy == NULL){
152
return false;
153
}
154
/* Insert the copy */
155
(*array)[*len] = copy;
156
(*len)++;
157
/* Add a new terminating NULL pointer to the last element */
158
(*array)[*len] = NULL;
159
return true;
160
}
161
162
/* Add to a plugin's argument vector */
163
static bool add_argument(plugin *p, const char *arg){
164
if(p == NULL){
165
return false;
166
}
167
return add_to_char_array(arg, &(p->argv), &(p->argc));
168
}
169
170
/* Add to a plugin's environment */
171
static bool add_environment(plugin *p, const char *def){
172
if(p == NULL){
173
return false;
174
}
175
return add_to_char_array(def, &(p->environ), &(p->envc));
176
}
177
178
179
/*
180
* Based on the example in the GNU LibC manual chapter 13.13 "File
181
* Descriptor Flags".
182
* *Note File Descriptor Flags:(libc)Descriptor Flags.
183
*/
184
static int set_cloexec_flag(int fd)
185
{
186
int ret = fcntl(fd, F_GETFD, 0);
187
/* If reading the flags failed, return error indication now. */
188
if(ret < 0){
189
return ret;
190
}
191
/* Store modified flag word in the descriptor. */
192
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
193
}
194
195
process *process_list = NULL;
196
197
/* Mark a process as completed when it exits, and save its exit
198
status. */
199
void handle_sigchld(__attribute__((unused)) int sig){
200
process *proc = process_list;
201
int status;
202
pid_t pid = wait(&status);
203
if(pid == -1){
204
perror("wait");
205
return;
206
}
207
while(proc != NULL and proc->pid != pid){
208
proc = proc->next;
209
}
210
if(proc == NULL){
211
/* Process not found in process list */
212
return;
213
}
214
proc->status = status;
215
proc->completed = true;
216
}
217
218
bool print_out_password(const char *buffer, size_t length){
219
ssize_t ret;
220
if(length>0 and buffer[length-1] == '\n'){
221
length--;
222
}
223
for(size_t written = 0; written < length; written += (size_t)ret){
224
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
225
length - written));
226
if(ret < 0){
227
return false;
228
}
229
}
230
return true;
231
}
232
233
char **add_to_argv(char **argv, int *argc, char *arg){
234
if (argv == NULL){
235
*argc = 1;
236
argv = malloc(sizeof(char*) * 2);
237
if(argv == NULL){
238
return NULL;
239
}
240
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
241
argv[1] = NULL;
242
}
243
*argc += 1;
244
argv = realloc(argv, sizeof(char *)
245
* ((unsigned int) *argc + 1));
246
if(argv == NULL){
247
return NULL;
248
}
249
argv[*argc-1] = arg;
250
argv[*argc] = NULL;
251
return argv;
252
}
253
254
static void free_plugin_list(plugin *plugin_list){
255
for(plugin *next = plugin_list; plugin_list != NULL; plugin_list = next){
256
next = plugin_list->next;
257
free(plugin_list->name);
258
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
259
free(*arg);
260
}
261
free(plugin_list->argv);
262
for(char **env = plugin_list->environ; *env != NULL; env++){
263
free(*env);
264
}
265
free(plugin_list->environ);
266
free(plugin_list);
267
}
268
}
269
270
int main(int argc, char *argv[]){
271
const char *plugindir = "/lib/mandos/plugins.d";
272
const char *argfile = ARGFILE;
273
FILE *conffp;
274
size_t d_name_len;
275
DIR *dir = NULL;
276
struct dirent *dirst;
277
struct stat st;
278
fd_set rfds_all;
279
int ret, maxfd = 0;
280
uid_t uid = 65534;
281
gid_t gid = 65534;
282
bool debug = false;
283
int exitstatus = EXIT_SUCCESS;
284
struct sigaction old_sigchld_action;
285
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
286
.sa_flags = SA_NOCLDSTOP };
287
char **custom_argv = NULL;
288
int custom_argc = 0;
289
290
/* Establish a signal handler */
291
sigemptyset(&sigchld_action.sa_mask);
292
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
293
if(ret == -1){
294
perror("sigaddset");
295
exitstatus = EXIT_FAILURE;
296
goto fallback;
297
}
298
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
299
if(ret == -1){
300
perror("sigaction");
301
exitstatus = EXIT_FAILURE;
302
goto fallback;
303
}
304
305
/* The options we understand. */
306
struct argp_option options[] = {
307
{ .name = "global-options", .key = 'g',
308
.arg = "OPTION[,OPTION[,...]]",
309
.doc = "Options passed to all plugins" },
310
{ .name = "global-envs", .key = 'e',
311
.arg = "VAR=value",
312
.doc = "Environment variable passed to all plugins" },
313
{ .name = "options-for", .key = 'o',
314
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
315
.doc = "Options passed only to specified plugin" },
316
{ .name = "envs-for", .key = 'f',
317
.arg = "PLUGIN:ENV=value",
318
.doc = "Environment variable passed to specified plugin" },
319
{ .name = "disable", .key = 'd',
320
.arg = "PLUGIN",
321
.doc = "Disable a specific plugin", .group = 1 },
322
{ .name = "plugin-dir", .key = 128,
323
.arg = "DIRECTORY",
324
.doc = "Specify a different plugin directory", .group = 2 },
325
{ .name = "userid", .key = 129,
326
.arg = "ID", .flags = 0,
327
.doc = "User ID the plugins will run as", .group = 2 },
328
{ .name = "groupid", .key = 130,
329
.arg = "ID", .flags = 0,
330
.doc = "Group ID the plugins will run as", .group = 2 },
331
{ .name = "debug", .key = 131,
332
.doc = "Debug mode", .group = 3 },
333
{ .name = NULL }
334
};
335
336
error_t parse_opt (int key, char *arg, struct argp_state *state) {
337
/* Get the INPUT argument from `argp_parse', which we know is a
338
pointer to our plugin list pointer. */
339
plugin **plugins = state->input;
340
switch (key) {
341
case 'g':
342
if (arg != NULL){
343
char *p;
344
while((p = strsep(&arg, ",")) != NULL){
345
if(p[0] == '\0'){
346
continue;
347
}
348
if(not add_argument(getplugin(NULL, plugins), p)){
349
perror("add_argument");
350
return ARGP_ERR_UNKNOWN;
351
}
352
}
353
}
354
break;
355
case 'e':
356
if(arg == NULL){
357
break;
358
}
359
{
360
char *envdef = strdup(arg);
361
if(envdef == NULL){
362
break;
363
}
364
if(not add_environment(getplugin(NULL, plugins), envdef)){
365
perror("add_environment");
366
}
367
}
368
break;
369
case 'o':
370
if (arg != NULL){
371
char *p_name = strsep(&arg, ":");
372
if(p_name[0] == '\0'){
373
break;
374
}
375
char *opt = strsep(&arg, ":");
376
if(opt[0] == '\0'){
377
break;
378
}
379
if(opt != NULL){
380
char *p;
381
while((p = strsep(&opt, ",")) != NULL){
382
if(p[0] == '\0'){
383
continue;
384
}
385
if(not add_argument(getplugin(p_name, plugins), p)){
386
perror("add_argument");
387
return ARGP_ERR_UNKNOWN;
388
}
389
}
390
}
391
}
392
break;
393
case 'f':
394
if(arg == NULL){
395
break;
396
}
397
{
398
char *envdef = strchr(arg, ':');
399
if(envdef == NULL){
400
break;
401
}
402
char *p_name = strndup(arg, (size_t) (envdef-arg));
403
if(p_name == NULL){
404
break;
405
}
406
envdef++;
407
if(not add_environment(getplugin(p_name, plugins), envdef)){
408
perror("add_environment");
409
}
410
}
411
break;
412
case 'd':
413
if (arg != NULL){
414
plugin *p = getplugin(arg, plugins);
415
if(p == NULL){
416
return ARGP_ERR_UNKNOWN;
417
}
418
p->disabled = true;
419
}
420
break;
421
case 128:
422
plugindir = arg;
423
break;
424
case 129:
425
uid = (uid_t)strtol(arg, NULL, 10);
426
break;
427
case 130:
428
gid = (gid_t)strtol(arg, NULL, 10);
429
break;
430
case 131:
431
debug = true;
432
break;
433
case ARGP_KEY_ARG:
434
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
435
break;
436
case ARGP_KEY_END:
437
break;
438
default:
439
return ARGP_ERR_UNKNOWN;
440
}
441
return 0;
442
}
443
444
plugin *plugin_list = NULL;
445
446
struct argp argp = { .options = options, .parser = parse_opt,
447
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
448
.doc = "Mandos plugin runner -- Run plugins" };
449
450
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
451
if (ret == ARGP_ERR_UNKNOWN){
452
fprintf(stderr, "Unknown error while parsing arguments\n");
453
exitstatus = EXIT_FAILURE;
454
goto fallback;
455
}
456
457
conffp = fopen(argfile, "r");
458
if(conffp != NULL){
459
char *org_line = NULL;
460
char *p, *arg, *new_arg, *line;
461
size_t size = 0;
462
ssize_t sret;
463
const char whitespace_delims[] = " \r\t\f\v\n";
464
const char comment_delim[] = "#";
465
466
while(true){
467
sret = getline(&org_line, &size, conffp);
468
if(sret == -1){
469
break;
470
}
471
472
line = org_line;
473
arg = strsep(&line, comment_delim);
474
while((p = strsep(&arg, whitespace_delims)) != NULL){
475
if(p[0] == '\0'){
476
continue;
477
}
478
new_arg = strdup(p);
479
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
480
if (custom_argv == NULL){
481
perror("add_to_argv");
482
exitstatus = EXIT_FAILURE;
483
goto fallback;
484
}
485
}
486
}
487
free(org_line);
488
} else{
489
/* Check for harmful errors and go to fallback. Other errors might
490
not affect opening plugins */
491
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
492
perror("fopen");
493
exitstatus = EXIT_FAILURE;
494
goto fallback;
495
}
496
}
497
498
if(custom_argv != NULL){
499
custom_argv[0] = argv[0];
500
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
501
if (ret == ARGP_ERR_UNKNOWN){
502
fprintf(stderr, "Unknown error while parsing arguments\n");
503
exitstatus = EXIT_FAILURE;
504
goto fallback;
505
}
506
}
507
508
if(debug){
509
for(plugin *p = plugin_list; p != NULL; p=p->next){
510
fprintf(stderr, "Plugin: %s has %d arguments\n",
511
p->name ? p->name : "Global", p->argc - 1);
512
for(char **a = p->argv; *a != NULL; a++){
513
fprintf(stderr, "\tArg: %s\n", *a);
514
}
515
fprintf(stderr, "...and %u environment variables\n", p->envc);
516
for(char **a = p->environ; *a != NULL; a++){
517
fprintf(stderr, "\t%s\n", *a);
518
}
519
}
520
}
521
522
ret = setuid(uid);
523
if (ret == -1){
524
perror("setuid");
525
}
526
527
setgid(gid);
528
if (ret == -1){
529
perror("setgid");
530
}
531
532
dir = opendir(plugindir);
533
if(dir == NULL){
534
perror("Could not open plugin dir");
535
exitstatus = EXIT_FAILURE;
536
goto fallback;
537
}
538
539
/* Set the FD_CLOEXEC flag on the directory, if possible */
540
{
541
int dir_fd = dirfd(dir);
542
if(dir_fd >= 0){
543
ret = set_cloexec_flag(dir_fd);
544
if(ret < 0){
545
perror("set_cloexec_flag");
546
exitstatus = EXIT_FAILURE;
547
goto fallback;
548
}
549
}
550
}
551
552
FD_ZERO(&rfds_all);
553
554
while(true){
555
dirst = readdir(dir);
556
557
// All directory entries have been processed
558
if(dirst == NULL){
559
if (errno == EBADF){
560
perror("readdir");
561
exitstatus = EXIT_FAILURE;
562
goto fallback;
563
}
564
break;
565
}
566
567
d_name_len = strlen(dirst->d_name);
568
569
// Ignore dotfiles, backup files and other junk
570
{
571
bool bad_name = false;
572
573
const char const *bad_prefixes[] = { ".", "#", NULL };
574
575
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
576
".dpkg-old",
577
".dpkg-divert", NULL };
578
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
579
size_t pre_len = strlen(*pre);
580
if((d_name_len >= pre_len)
581
and strncmp((dirst->d_name), *pre, pre_len) == 0){
582
if(debug){
583
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
584
" with bad prefix %s\n", dirst->d_name, *pre);
585
}
586
bad_name = true;
587
break;
588
}
589
}
590
591
if(bad_name){
592
continue;
593
}
594
595
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
596
size_t suf_len = strlen(*suf);
597
if((d_name_len >= suf_len)
598
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
599
== 0)){
600
if(debug){
601
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
602
" with bad suffix %s\n", dirst->d_name, *suf);
603
}
604
bad_name = true;
605
break;
606
}
607
}
608
609
if(bad_name){
610
continue;
611
}
612
}
613
614
char *filename;
615
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
616
if(ret < 0){
617
perror("asprintf");
618
continue;
619
}
620
621
ret = stat(filename, &st);
622
if (ret == -1){
623
perror("stat");
624
free(filename);
625
continue;
626
}
627
628
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
629
if(debug){
630
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
631
" with bad type or mode\n", filename);
632
}
633
free(filename);
634
continue;
635
}
636
plugin *p = getplugin(dirst->d_name, &plugin_list);
637
if(p == NULL){
638
perror("getplugin");
639
free(filename);
640
continue;
641
}
642
if(p->disabled){
643
if(debug){
644
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
645
dirst->d_name);
646
}
647
free(filename);
648
continue;
649
}
650
{
651
/* Add global arguments to argument list for this plugin */
652
plugin *g = getplugin(NULL, &plugin_list);
653
if(g != NULL){
654
for(char **a = g->argv + 1; *a != NULL; a++){
655
if(not add_argument(p, *a)){
656
perror("add_argument");
657
}
658
}
659
/* Add global environment variables */
660
for(char **e = g->environ; *e != NULL; e++){
661
if(not add_environment(p, *e)){
662
perror("add_environment");
663
}
664
}
665
}
666
}
667
/* If this plugin has any environment variables, we will call
668
using execve and need to duplicate the environment from this
669
process, too. */
670
if(p->environ[0] != NULL){
671
for(char **e = environ; *e != NULL; e++){
672
char *copy = strdup(*e);
673
if(copy == NULL){
674
perror("strdup");
675
continue;
676
}
677
if(not add_environment(p, copy)){
678
perror("add_environment");
679
}
680
}
681
}
682
683
int pipefd[2];
684
ret = pipe(pipefd);
685
if (ret == -1){
686
perror("pipe");
687
exitstatus = EXIT_FAILURE;
688
goto fallback;
689
}
690
ret = set_cloexec_flag(pipefd[0]);
691
if(ret < 0){
692
perror("set_cloexec_flag");
693
exitstatus = EXIT_FAILURE;
694
goto fallback;
695
}
696
ret = set_cloexec_flag(pipefd[1]);
697
if(ret < 0){
698
perror("set_cloexec_flag");
699
exitstatus = EXIT_FAILURE;
700
goto fallback;
701
}
702
/* Block SIGCHLD until process is safely in process list */
703
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
704
if(ret < 0){
705
perror("sigprocmask");
706
exitstatus = EXIT_FAILURE;
707
goto fallback;
708
}
709
// Starting a new process to be watched
710
pid_t pid = fork();
711
if(pid == -1){
712
perror("fork");
713
exitstatus = EXIT_FAILURE;
714
goto fallback;
715
}
716
if(pid == 0){
717
/* this is the child process */
718
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
719
if(ret < 0){
720
perror("sigaction");
721
_exit(EXIT_FAILURE);
722
}
723
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
724
if(ret < 0){
725
perror("sigprocmask");
726
_exit(EXIT_FAILURE);
727
}
728
729
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
730
if(ret == -1){
731
perror("dup2");
732
_exit(EXIT_FAILURE);
733
}
734
735
if(dirfd(dir) < 0){
736
/* If dir has no file descriptor, we could not set FD_CLOEXEC
737
above and must now close it manually here. */
738
closedir(dir);
739
}
740
if(p->environ[0] == NULL){
741
if(execv(filename, p->argv) < 0){
742
perror("execv");
743
_exit(EXIT_FAILURE);
744
}
745
} else {
746
if(execve(filename, p->argv, p->environ) < 0){
747
perror("execve");
748
_exit(EXIT_FAILURE);
749
}
750
}
751
/* no return */
752
}
753
/* parent process */
754
free(filename);
755
close(pipefd[1]); /* close unused write end of pipe */
756
process *new_process = malloc(sizeof(process));
757
if (new_process == NULL){
758
perror("malloc");
759
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
760
if(ret < 0){
761
perror("sigprocmask");
762
}
763
exitstatus = EXIT_FAILURE;
764
goto fallback;
765
}
766
767
*new_process = (struct process){ .pid = pid,
768
.fd = pipefd[0],
769
.next = process_list };
770
// List handling
771
process_list = new_process;
772
/* Unblock SIGCHLD so signal handler can be run if this process
773
has already completed */
774
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
775
if(ret < 0){
776
perror("sigprocmask");
777
exitstatus = EXIT_FAILURE;
778
goto fallback;
779
}
780
781
FD_SET(new_process->fd, &rfds_all);
782
783
if (maxfd < new_process->fd){
784
maxfd = new_process->fd;
785
}
786
787
}
788
789
free_plugin_list(plugin_list);
790
791
closedir(dir);
792
dir = NULL;
793
794
if (process_list == NULL){
795
fprintf(stderr, "No plugin processes started. Incorrect plugin"
796
" directory?\n");
797
process_list = NULL;
798
}
799
while(process_list){
800
fd_set rfds = rfds_all;
801
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
802
if (select_ret == -1){
803
perror("select");
804
exitstatus = EXIT_FAILURE;
805
goto fallback;
806
}
807
/* OK, now either a process completed, or something can be read
808
from one of them */
809
for(process *proc = process_list; proc ; proc = proc->next){
810
/* Is this process completely done? */
811
if(proc->eof and proc->completed){
812
/* Only accept the plugin output if it exited cleanly */
813
if(not WIFEXITED(proc->status)
814
or WEXITSTATUS(proc->status) != 0){
815
/* Bad exit by plugin */
816
if(debug){
817
if(WIFEXITED(proc->status)){
818
fprintf(stderr, "Plugin %u exited with status %d\n",
819
(unsigned int) (proc->pid),
820
WEXITSTATUS(proc->status));
821
} else if(WIFSIGNALED(proc->status)) {
822
fprintf(stderr, "Plugin %u killed by signal %d\n",
823
(unsigned int) (proc->pid),
824
WTERMSIG(proc->status));
825
} else if(WCOREDUMP(proc->status)){
826
fprintf(stderr, "Plugin %d dumped core\n",
827
(unsigned int) (proc->pid));
828
}
829
}
830
/* Remove the plugin */
831
FD_CLR(proc->fd, &rfds_all);
832
/* Block signal while modifying process_list */
833
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
834
if(ret < 0){
835
perror("sigprocmask");
836
exitstatus = EXIT_FAILURE;
837
goto fallback;
838
}
839
/* Delete this process entry from the list */
840
if(process_list == proc){
841
/* First one - simple */
842
process_list = proc->next;
843
} else {
844
/* Second one or later */
845
for(process *p = process_list; p != NULL; p = p->next){
846
if(p->next == proc){
847
p->next = proc->next;
848
break;
849
}
850
}
851
}
852
/* We are done modifying process list, so unblock signal */
853
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
854
NULL);
855
if(ret < 0){
856
perror("sigprocmask");
857
}
858
free(proc->buffer);
859
free(proc);
860
/* We deleted this process from the list, so we can't go
861
proc->next. Therefore, start over from the beginning of
862
the process list */
863
break;
864
}
865
/* This process exited nicely, so print its buffer */
866
867
bool bret = print_out_password(proc->buffer, proc->buffer_length);
868
if(not bret){
869
perror("print_out_password");
870
exitstatus = EXIT_FAILURE;
871
}
872
goto fallback;
873
}
874
/* This process has not completed. Does it have any output? */
875
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
876
/* This process had nothing to say at this time */
877
continue;
878
}
879
/* Before reading, make the process' data buffer large enough */
880
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
881
proc->buffer = realloc(proc->buffer, proc->buffer_size
882
+ (size_t) BUFFER_SIZE);
883
if (proc->buffer == NULL){
884
perror("malloc");
885
exitstatus = EXIT_FAILURE;
886
goto fallback;
887
}
888
proc->buffer_size += BUFFER_SIZE;
889
}
890
/* Read from the process */
891
ret = read(proc->fd, proc->buffer + proc->buffer_length,
892
BUFFER_SIZE);
893
if(ret < 0){
894
/* Read error from this process; ignore the error */
895
continue;
896
}
897
if(ret == 0){
898
/* got EOF */
899
proc->eof = true;
900
} else {
901
proc->buffer_length += (size_t) ret;
902
}
903
}
904
}
905
906
907
fallback:
908
909
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
910
/* Fallback if all plugins failed, none are found or an error occured */
911
bool bret;
912
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
913
char *passwordbuffer = getpass("Password: ");
914
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
915
if(not bret){
916
perror("print_out_password");
917
exitstatus = EXIT_FAILURE;
918
}
919
}
920
921
/* Restore old signal handler */
922
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
923
if(ret == -1){
924
perror("sigaction");
925
exitstatus = EXIT_FAILURE;
926
}
927
928
if(custom_argv != NULL){
929
for(char **arg = custom_argv; *arg != NULL; arg++){
930
free(*arg);
931
}
932
free(custom_argv);
933
}
934
free_plugin_list(plugin_list);
935
936
if(dir != NULL){
937
closedir(dir);
938
}
939
940
/* Free the process list and kill the processes */
941
for(process *next; process_list != NULL; process_list = next){
942
next = process_list->next;
943
close(process_list->fd);
944
ret = kill(process_list->pid, SIGTERM);
945
if(ret == -1 and errno != ESRCH){
946
/* set-uid proccesses migth not get closed */
947
perror("kill");
948
}
949
free(process_list->buffer);
950
free(process_list);
951
}
952
953
/* Wait for any remaining child processes to terminate */
954
do{
955
ret = wait(NULL);
956
} while(ret >= 0);
957
if(errno != ECHILD){
958
perror("wait");
959
}
960
961
return exitstatus;
962
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0