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- Committer: Teddy Hogeborn
- Date: 2008-01-18 21:23:46 UTC
- mfrom: (2.1.1 Project)
- Revision ID: teddy@fukt.bsnet.se-20080118212346-qo103d6o8r7xs4za
Merged from Björn.
- files added:
- ca.pem
- files removed:
- COPYING
- plugins.d
- files renamed:
- clients.conf => mandos-clients.conf
- mandos => server.py
- 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 = NULL;
109
if(name != NULL){
110
copy_name = strdup(name);
111
}
112
if(copy_name == NULL){
113
return NULL;
114
}
115
116
*new_plugin = (plugin) { .name = copy_name,
117
.argc = 1,
118
.envc = 0,
119
.disabled = false,
120
.next = *plugin_list };
121
122
new_plugin->argv = malloc(sizeof(char *) * 2);
123
if (new_plugin->argv == NULL){
124
free(copy_name);
125
free(new_plugin);
126
return NULL;
127
}
128
new_plugin->argv[0] = copy_name;
129
new_plugin->argv[1] = NULL;
130
131
new_plugin->environ = malloc(sizeof(char *));
132
if(new_plugin->environ == NULL){
133
free(copy_name);
134
free(new_plugin->argv);
135
free(new_plugin);
136
return NULL;
137
}
138
new_plugin->environ[0] = NULL;
139
/* Append the new plugin to the list */
140
*plugin_list = new_plugin;
141
return new_plugin;
142
}
143
144
/* Helper function for add_argument and add_environment */
145
static bool add_to_char_array(const char *new, char ***array,
146
int *len){
147
/* Resize the pointed-to array to hold one more pointer */
148
*array = realloc(*array, sizeof(char *)
149
* (size_t) ((*len) + 2));
150
/* Malloc check */
151
if(*array == NULL){
152
return false;
153
}
154
/* Make a copy of the new string */
155
char *copy = strdup(new);
156
if(copy == NULL){
157
return false;
158
}
159
/* Insert the copy */
160
(*array)[*len] = copy;
161
(*len)++;
162
/* Add a new terminating NULL pointer to the last element */
163
(*array)[*len] = NULL;
164
return true;
165
}
166
167
/* Add to a plugin's argument vector */
168
static bool add_argument(plugin *p, const char *arg){
169
if(p == NULL){
170
return false;
171
}
172
return add_to_char_array(arg, &(p->argv), &(p->argc));
173
}
174
175
/* Add to a plugin's environment */
176
static bool add_environment(plugin *p, const char *def){
177
if(p == NULL){
178
return false;
179
}
180
return add_to_char_array(def, &(p->environ), &(p->envc));
181
}
182
183
184
/*
185
* Based on the example in the GNU LibC manual chapter 13.13 "File
186
* Descriptor Flags".
187
* *Note File Descriptor Flags:(libc)Descriptor Flags.
188
*/
189
static int set_cloexec_flag(int fd)
190
{
191
int ret = fcntl(fd, F_GETFD, 0);
192
/* If reading the flags failed, return error indication now. */
193
if(ret < 0){
194
return ret;
195
}
196
/* Store modified flag word in the descriptor. */
197
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
198
}
199
200
process *process_list = NULL;
201
202
/* Mark a process as completed when it exits, and save its exit
203
status. */
204
void handle_sigchld(__attribute__((unused)) int sig){
205
process *proc = process_list;
206
int status;
207
pid_t pid = wait(&status);
208
if(pid == -1){
209
perror("wait");
210
return;
211
}
212
while(proc != NULL and proc->pid != pid){
213
proc = proc->next;
214
}
215
if(proc == NULL){
216
/* Process not found in process list */
217
return;
218
}
219
proc->status = status;
220
proc->completed = true;
221
}
222
223
bool print_out_password(const char *buffer, size_t length){
224
ssize_t ret;
225
if(length>0 and buffer[length-1] == '\n'){
226
length--;
227
}
228
for(size_t written = 0; written < length; written += (size_t)ret){
229
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
230
length - written));
231
if(ret < 0){
232
return false;
233
}
234
}
235
return true;
236
}
237
238
char **add_to_argv(char **argv, int *argc, char *arg){
239
if (argv == NULL){
240
*argc = 1;
241
argv = malloc(sizeof(char*) * 2);
242
if(argv == NULL){
243
return NULL;
244
}
245
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
246
argv[1] = NULL;
247
}
248
*argc += 1;
249
argv = realloc(argv, sizeof(char *)
250
* ((unsigned int) *argc + 1));
251
if(argv == NULL){
252
return NULL;
253
}
254
argv[*argc-1] = arg;
255
argv[*argc] = NULL;
256
return argv;
257
}
258
259
static void free_plugin_list(plugin *plugin_list){
260
for(plugin *next = plugin_list; plugin_list != NULL; plugin_list = next){
261
next = plugin_list->next;
262
free(plugin_list->name);
263
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
264
free(*arg);
265
}
266
free(plugin_list->argv);
267
for(char **env = plugin_list->environ; *env != NULL; env++){
268
free(*env);
269
}
270
free(plugin_list->environ);
271
free(plugin_list);
272
}
273
}
274
275
int main(int argc, char *argv[]){
276
const char *plugindir = "/lib/mandos/plugins.d";
277
const char *argfile = ARGFILE;
278
FILE *conffp;
279
size_t d_name_len;
280
DIR *dir = NULL;
281
struct dirent *dirst;
282
struct stat st;
283
fd_set rfds_all;
284
int ret, maxfd = 0;
285
uid_t uid = 65534;
286
gid_t gid = 65534;
287
bool debug = false;
288
int exitstatus = EXIT_SUCCESS;
289
struct sigaction old_sigchld_action;
290
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
291
.sa_flags = SA_NOCLDSTOP };
292
char **custom_argv = NULL;
293
int custom_argc = 0;
294
295
/* Establish a signal handler */
296
sigemptyset(&sigchld_action.sa_mask);
297
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
298
if(ret == -1){
299
perror("sigaddset");
300
exitstatus = EXIT_FAILURE;
301
goto fallback;
302
}
303
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
304
if(ret == -1){
305
perror("sigaction");
306
exitstatus = EXIT_FAILURE;
307
goto fallback;
308
}
309
310
/* The options we understand. */
311
struct argp_option options[] = {
312
{ .name = "global-options", .key = 'g',
313
.arg = "OPTION[,OPTION[,...]]",
314
.doc = "Options passed to all plugins" },
315
{ .name = "global-envs", .key = 'e',
316
.arg = "VAR=value",
317
.doc = "Environment variable passed to all plugins" },
318
{ .name = "options-for", .key = 'o',
319
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
320
.doc = "Options passed only to specified plugin" },
321
{ .name = "envs-for", .key = 'f',
322
.arg = "PLUGIN:ENV=value",
323
.doc = "Environment variable passed to specified plugin" },
324
{ .name = "disable", .key = 'd',
325
.arg = "PLUGIN",
326
.doc = "Disable a specific plugin", .group = 1 },
327
{ .name = "plugin-dir", .key = 128,
328
.arg = "DIRECTORY",
329
.doc = "Specify a different plugin directory", .group = 2 },
330
{ .name = "userid", .key = 129,
331
.arg = "ID", .flags = 0,
332
.doc = "User ID the plugins will run as", .group = 2 },
333
{ .name = "groupid", .key = 130,
334
.arg = "ID", .flags = 0,
335
.doc = "Group ID the plugins will run as", .group = 2 },
336
{ .name = "debug", .key = 131,
337
.doc = "Debug mode", .group = 3 },
338
{ .name = NULL }
339
};
340
341
error_t parse_opt (int key, char *arg, struct argp_state *state) {
342
/* Get the INPUT argument from `argp_parse', which we know is a
343
pointer to our plugin list pointer. */
344
plugin **plugins = state->input;
345
switch (key) {
346
case 'g':
347
if (arg != NULL){
348
char *p;
349
while((p = strsep(&arg, ",")) != NULL){
350
if(p[0] == '\0'){
351
continue;
352
}
353
if(not add_argument(getplugin(NULL, plugins), p)){
354
perror("add_argument");
355
return ARGP_ERR_UNKNOWN;
356
}
357
}
358
}
359
break;
360
case 'e':
361
if(arg == NULL){
362
break;
363
}
364
{
365
char *envdef = strdup(arg);
366
if(envdef == NULL){
367
break;
368
}
369
if(not add_environment(getplugin(NULL, plugins), envdef)){
370
perror("add_environment");
371
}
372
}
373
break;
374
case 'o':
375
if (arg != NULL){
376
char *p_name = strsep(&arg, ":");
377
if(p_name[0] == '\0'){
378
break;
379
}
380
char *opt = strsep(&arg, ":");
381
if(opt[0] == '\0'){
382
break;
383
}
384
if(opt != NULL){
385
char *p;
386
while((p = strsep(&opt, ",")) != NULL){
387
if(p[0] == '\0'){
388
continue;
389
}
390
if(not add_argument(getplugin(p_name, plugins), p)){
391
perror("add_argument");
392
return ARGP_ERR_UNKNOWN;
393
}
394
}
395
}
396
}
397
break;
398
case 'f':
399
if(arg == NULL){
400
break;
401
}
402
{
403
char *envdef = strchr(arg, ':');
404
if(envdef == NULL){
405
break;
406
}
407
char *p_name = strndup(arg, (size_t) (envdef-arg));
408
if(p_name == NULL){
409
break;
410
}
411
envdef++;
412
if(not add_environment(getplugin(p_name, plugins), envdef)){
413
perror("add_environment");
414
}
415
}
416
break;
417
case 'd':
418
if (arg != NULL){
419
plugin *p = getplugin(arg, plugins);
420
if(p == NULL){
421
return ARGP_ERR_UNKNOWN;
422
}
423
p->disabled = true;
424
}
425
break;
426
case 128:
427
plugindir = arg;
428
break;
429
case 129:
430
uid = (uid_t)strtol(arg, NULL, 10);
431
break;
432
case 130:
433
gid = (gid_t)strtol(arg, NULL, 10);
434
break;
435
case 131:
436
debug = true;
437
break;
438
case ARGP_KEY_ARG:
439
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
440
break;
441
case ARGP_KEY_END:
442
break;
443
default:
444
return ARGP_ERR_UNKNOWN;
445
}
446
return 0;
447
}
448
449
plugin *plugin_list = NULL;
450
451
struct argp argp = { .options = options, .parser = parse_opt,
452
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
453
.doc = "Mandos plugin runner -- Run plugins" };
454
455
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
456
if (ret == ARGP_ERR_UNKNOWN){
457
fprintf(stderr, "Unknown error while parsing arguments\n");
458
exitstatus = EXIT_FAILURE;
459
goto fallback;
460
}
461
462
conffp = fopen(argfile, "r");
463
if(conffp != NULL){
464
char *org_line = NULL;
465
char *p, *arg, *new_arg, *line;
466
size_t size = 0;
467
ssize_t sret;
468
const char whitespace_delims[] = " \r\t\f\v\n";
469
const char comment_delim[] = "#";
470
471
while(true){
472
sret = getline(&org_line, &size, conffp);
473
if(sret == -1){
474
break;
475
}
476
477
line = org_line;
478
arg = strsep(&line, comment_delim);
479
while((p = strsep(&arg, whitespace_delims)) != NULL){
480
if(p[0] == '\0'){
481
continue;
482
}
483
new_arg = strdup(p);
484
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
485
if (custom_argv == NULL){
486
perror("add_to_argv");
487
exitstatus = EXIT_FAILURE;
488
goto fallback;
489
}
490
}
491
}
492
free(org_line);
493
} else{
494
/* Check for harmful errors and go to fallback. Other errors might
495
not affect opening plugins */
496
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
497
perror("fopen");
498
exitstatus = EXIT_FAILURE;
499
goto fallback;
500
}
501
}
502
503
if(custom_argv != NULL){
504
custom_argv[0] = argv[0];
505
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
506
if (ret == ARGP_ERR_UNKNOWN){
507
fprintf(stderr, "Unknown error while parsing arguments\n");
508
exitstatus = EXIT_FAILURE;
509
goto fallback;
510
}
511
}
512
513
if(debug){
514
for(plugin *p = plugin_list; p != NULL; p=p->next){
515
fprintf(stderr, "Plugin: %s has %d arguments\n",
516
p->name ? p->name : "Global", p->argc - 1);
517
for(char **a = p->argv; *a != NULL; a++){
518
fprintf(stderr, "\tArg: %s\n", *a);
519
}
520
fprintf(stderr, "...and %u environment variables\n", p->envc);
521
for(char **a = p->environ; *a != NULL; a++){
522
fprintf(stderr, "\t%s\n", *a);
523
}
524
}
525
}
526
527
ret = setuid(uid);
528
if (ret == -1){
529
perror("setuid");
530
}
531
532
setgid(gid);
533
if (ret == -1){
534
perror("setgid");
535
}
536
537
dir = opendir(plugindir);
538
if(dir == NULL){
539
perror("Could not open plugin dir");
540
exitstatus = EXIT_FAILURE;
541
goto fallback;
542
}
543
544
/* Set the FD_CLOEXEC flag on the directory, if possible */
545
{
546
int dir_fd = dirfd(dir);
547
if(dir_fd >= 0){
548
ret = set_cloexec_flag(dir_fd);
549
if(ret < 0){
550
perror("set_cloexec_flag");
551
exitstatus = EXIT_FAILURE;
552
goto fallback;
553
}
554
}
555
}
556
557
FD_ZERO(&rfds_all);
558
559
while(true){
560
dirst = readdir(dir);
561
562
// All directory entries have been processed
563
if(dirst == NULL){
564
if (errno == EBADF){
565
perror("readdir");
566
exitstatus = EXIT_FAILURE;
567
goto fallback;
568
}
569
break;
570
}
571
572
d_name_len = strlen(dirst->d_name);
573
574
// Ignore dotfiles, backup files and other junk
575
{
576
bool bad_name = false;
577
578
const char const *bad_prefixes[] = { ".", "#", NULL };
579
580
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
581
".dpkg-old",
582
".dpkg-divert", NULL };
583
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
584
size_t pre_len = strlen(*pre);
585
if((d_name_len >= pre_len)
586
and strncmp((dirst->d_name), *pre, pre_len) == 0){
587
if(debug){
588
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
589
" with bad prefix %s\n", dirst->d_name, *pre);
590
}
591
bad_name = true;
592
break;
593
}
594
}
595
596
if(bad_name){
597
continue;
598
}
599
600
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
601
size_t suf_len = strlen(*suf);
602
if((d_name_len >= suf_len)
603
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
604
== 0)){
605
if(debug){
606
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
607
" with bad suffix %s\n", dirst->d_name, *suf);
608
}
609
bad_name = true;
610
break;
611
}
612
}
613
614
if(bad_name){
615
continue;
616
}
617
}
618
619
char *filename;
620
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
621
if(ret < 0){
622
perror("asprintf");
623
continue;
624
}
625
626
ret = stat(filename, &st);
627
if (ret == -1){
628
perror("stat");
629
free(filename);
630
continue;
631
}
632
633
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
634
if(debug){
635
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
636
" with bad type or mode\n", filename);
637
}
638
free(filename);
639
continue;
640
}
641
plugin *p = getplugin(dirst->d_name, &plugin_list);
642
if(p == NULL){
643
perror("getplugin");
644
free(filename);
645
continue;
646
}
647
if(p->disabled){
648
if(debug){
649
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
650
dirst->d_name);
651
}
652
free(filename);
653
continue;
654
}
655
{
656
/* Add global arguments to argument list for this plugin */
657
plugin *g = getplugin(NULL, &plugin_list);
658
if(g != NULL){
659
for(char **a = g->argv + 1; *a != NULL; a++){
660
if(not add_argument(p, *a)){
661
perror("add_argument");
662
}
663
}
664
/* Add global environment variables */
665
for(char **e = g->environ; *e != NULL; e++){
666
if(not add_environment(p, *e)){
667
perror("add_environment");
668
}
669
}
670
}
671
}
672
/* If this plugin has any environment variables, we will call
673
using execve and need to duplicate the environment from this
674
process, too. */
675
if(p->environ[0] != NULL){
676
for(char **e = environ; *e != NULL; e++){
677
char *copy = strdup(*e);
678
if(copy == NULL){
679
perror("strdup");
680
continue;
681
}
682
if(not add_environment(p, copy)){
683
perror("add_environment");
684
}
685
}
686
}
687
688
int pipefd[2];
689
ret = pipe(pipefd);
690
if (ret == -1){
691
perror("pipe");
692
exitstatus = EXIT_FAILURE;
693
goto fallback;
694
}
695
ret = set_cloexec_flag(pipefd[0]);
696
if(ret < 0){
697
perror("set_cloexec_flag");
698
exitstatus = EXIT_FAILURE;
699
goto fallback;
700
}
701
ret = set_cloexec_flag(pipefd[1]);
702
if(ret < 0){
703
perror("set_cloexec_flag");
704
exitstatus = EXIT_FAILURE;
705
goto fallback;
706
}
707
/* Block SIGCHLD until process is safely in process list */
708
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
709
if(ret < 0){
710
perror("sigprocmask");
711
exitstatus = EXIT_FAILURE;
712
goto fallback;
713
}
714
// Starting a new process to be watched
715
pid_t pid = fork();
716
if(pid == -1){
717
perror("fork");
718
exitstatus = EXIT_FAILURE;
719
goto fallback;
720
}
721
if(pid == 0){
722
/* this is the child process */
723
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
724
if(ret < 0){
725
perror("sigaction");
726
_exit(EXIT_FAILURE);
727
}
728
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
729
if(ret < 0){
730
perror("sigprocmask");
731
_exit(EXIT_FAILURE);
732
}
733
734
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
735
if(ret == -1){
736
perror("dup2");
737
_exit(EXIT_FAILURE);
738
}
739
740
if(dirfd(dir) < 0){
741
/* If dir has no file descriptor, we could not set FD_CLOEXEC
742
above and must now close it manually here. */
743
closedir(dir);
744
}
745
if(p->environ[0] == NULL){
746
if(execv(filename, p->argv) < 0){
747
perror("execv");
748
_exit(EXIT_FAILURE);
749
}
750
} else {
751
if(execve(filename, p->argv, p->environ) < 0){
752
perror("execve");
753
_exit(EXIT_FAILURE);
754
}
755
}
756
/* no return */
757
}
758
/* parent process */
759
free(filename);
760
close(pipefd[1]); /* close unused write end of pipe */
761
process *new_process = malloc(sizeof(process));
762
if (new_process == NULL){
763
perror("malloc");
764
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
765
if(ret < 0){
766
perror("sigprocmask");
767
}
768
exitstatus = EXIT_FAILURE;
769
goto fallback;
770
}
771
772
*new_process = (struct process){ .pid = pid,
773
.fd = pipefd[0],
774
.next = process_list };
775
// List handling
776
process_list = new_process;
777
/* Unblock SIGCHLD so signal handler can be run if this process
778
has already completed */
779
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
780
if(ret < 0){
781
perror("sigprocmask");
782
exitstatus = EXIT_FAILURE;
783
goto fallback;
784
}
785
786
FD_SET(new_process->fd, &rfds_all);
787
788
if (maxfd < new_process->fd){
789
maxfd = new_process->fd;
790
}
791
792
}
793
794
free_plugin_list(plugin_list);
795
796
closedir(dir);
797
dir = NULL;
798
799
if (process_list == NULL){
800
fprintf(stderr, "No plugin processes started. Incorrect plugin"
801
" directory?\n");
802
process_list = NULL;
803
}
804
while(process_list){
805
fd_set rfds = rfds_all;
806
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
807
if (select_ret == -1){
808
perror("select");
809
exitstatus = EXIT_FAILURE;
810
goto fallback;
811
}
812
/* OK, now either a process completed, or something can be read
813
from one of them */
814
for(process *proc = process_list; proc ; proc = proc->next){
815
/* Is this process completely done? */
816
if(proc->eof and proc->completed){
817
/* Only accept the plugin output if it exited cleanly */
818
if(not WIFEXITED(proc->status)
819
or WEXITSTATUS(proc->status) != 0){
820
/* Bad exit by plugin */
821
if(debug){
822
if(WIFEXITED(proc->status)){
823
fprintf(stderr, "Plugin %u exited with status %d\n",
824
(unsigned int) (proc->pid),
825
WEXITSTATUS(proc->status));
826
} else if(WIFSIGNALED(proc->status)) {
827
fprintf(stderr, "Plugin %u killed by signal %d\n",
828
(unsigned int) (proc->pid),
829
WTERMSIG(proc->status));
830
} else if(WCOREDUMP(proc->status)){
831
fprintf(stderr, "Plugin %d dumped core\n",
832
(unsigned int) (proc->pid));
833
}
834
}
835
/* Remove the plugin */
836
FD_CLR(proc->fd, &rfds_all);
837
/* Block signal while modifying process_list */
838
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
839
if(ret < 0){
840
perror("sigprocmask");
841
exitstatus = EXIT_FAILURE;
842
goto fallback;
843
}
844
/* Delete this process entry from the list */
845
if(process_list == proc){
846
/* First one - simple */
847
process_list = proc->next;
848
} else {
849
/* Second one or later */
850
for(process *p = process_list; p != NULL; p = p->next){
851
if(p->next == proc){
852
p->next = proc->next;
853
break;
854
}
855
}
856
}
857
/* We are done modifying process list, so unblock signal */
858
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
859
NULL);
860
if(ret < 0){
861
perror("sigprocmask");
862
}
863
free(proc->buffer);
864
free(proc);
865
/* We deleted this process from the list, so we can't go
866
proc->next. Therefore, start over from the beginning of
867
the process list */
868
break;
869
}
870
/* This process exited nicely, so print its buffer */
871
872
bool bret = print_out_password(proc->buffer, proc->buffer_length);
873
if(not bret){
874
perror("print_out_password");
875
exitstatus = EXIT_FAILURE;
876
}
877
goto fallback;
878
}
879
/* This process has not completed. Does it have any output? */
880
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
881
/* This process had nothing to say at this time */
882
continue;
883
}
884
/* Before reading, make the process' data buffer large enough */
885
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
886
proc->buffer = realloc(proc->buffer, proc->buffer_size
887
+ (size_t) BUFFER_SIZE);
888
if (proc->buffer == NULL){
889
perror("malloc");
890
exitstatus = EXIT_FAILURE;
891
goto fallback;
892
}
893
proc->buffer_size += BUFFER_SIZE;
894
}
895
/* Read from the process */
896
ret = read(proc->fd, proc->buffer + proc->buffer_length,
897
BUFFER_SIZE);
898
if(ret < 0){
899
/* Read error from this process; ignore the error */
900
continue;
901
}
902
if(ret == 0){
903
/* got EOF */
904
proc->eof = true;
905
} else {
906
proc->buffer_length += (size_t) ret;
907
}
908
}
909
}
910
911
912
fallback:
913
914
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
915
/* Fallback if all plugins failed, none are found or an error occured */
916
bool bret;
917
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
918
char *passwordbuffer = getpass("Password: ");
919
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
920
if(not bret){
921
perror("print_out_password");
922
exitstatus = EXIT_FAILURE;
923
}
924
}
925
926
/* Restore old signal handler */
927
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
928
if(ret == -1){
929
perror("sigaction");
930
exitstatus = EXIT_FAILURE;
931
}
932
933
if(custom_argv != NULL){
934
for(char **arg = custom_argv; *arg != NULL; arg++){
935
free(*arg);
936
}
937
free(custom_argv);
938
}
939
free_plugin_list(plugin_list);
940
941
if(dir != NULL){
942
closedir(dir);
943
}
944
945
/* Free the process list and kill the processes */
946
for(process *next; process_list != NULL; process_list = next){
947
next = process_list->next;
948
close(process_list->fd);
949
ret = kill(process_list->pid, SIGTERM);
950
if(ret == -1 and errno != ESRCH){
951
/* set-uid proccesses migth not get closed */
952
perror("kill");
953
}
954
free(process_list->buffer);
955
free(process_list);
956
}
957
958
/* Wait for any remaining child processes to terminate */
959
do{
960
ret = wait(NULL);
961
} while(ret >= 0);
962
if(errno != ECHILD){
963
perror("wait");
964
}
965
966
return exitstatus;
967
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0