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- Committer: Teddy Hogeborn
- Date: 2008-08-16 03:29:08 UTC
- Revision ID: teddy@fukt.bsnet.se-20080816032908-ihw7c05r2mnyk389
Add feature to specify custom environment variables for plugins.
* plugin-runner.c (plugin): New members "environ" and "envc" to
contain possible custom environment.
(getplugin): Return NULL on failure instead of doing exit(); all
callers changed.
(add_to_char_array): New helper function for "add_argument" and
"add_environment".
(addargument): Renamed to "add_argument". Return bool. Call
"add_to_char_array" to actually do things.
(add_environment): New; analogous to "add_argument".
(addcustomargument): Renamed to "add_to_argv" to avoid confusion
with "add_argument".
(main): New options "--global-envs" and "--envs-for" to specify
custom environment for plugins. Print environment for
plugins in debug mode. Use asprintf instead of strcpy and
strcat. Use execve() for plugins with custom environments.
Free environment for plugin when freeing plugin list.
* plugin-runner.c (plugin): New members "environ" and "envc" to
contain possible custom environment.
(getplugin): Return NULL on failure instead of doing exit(); all
callers changed.
(add_to_char_array): New helper function for "add_argument" and
"add_environment".
(addargument): Renamed to "add_argument". Return bool. Call
"add_to_char_array" to actually do things.
(add_environment): New; analogous to "add_argument".
(addcustomargument): Renamed to "add_to_argv" to avoid confusion
with "add_argument".
(main): New options "--global-envs" and "--envs-for" to specify
custom environment for plugins. Print environment for
plugins in debug mode. Use asprintf instead of strcpy and
strcat. Use execve() for plugins with custom environments.
Free environment for plugin when freeing plugin list.
- files added:
- COPYING
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- plugbasedclient.c => plugin-runner.c
- plugins.d/passprompt.c => plugins.d/password-prompt.c
- plugins.d/mandosclient.c => plugins.d/password-request.c
- files modified:
- Makefile
added
removed
plugin-runner.c
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 */
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>";
15
71
16
72
struct process;
17
73
19
75
pid_t pid;
20
76
int fd;
21
77
char *buffer;
22
int buffer_size;
23
int buffer_length;
78
size_t buffer_size;
79
size_t buffer_length;
80
bool eof;
81
bool completed;
82
int status;
24
83
struct process *next;
25
84
} process;
26
85
27
#define BUFFER_SIZE 256
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
*new_plugin = (plugin) { .name = name,
109
.argc = 1,
110
.envc = 0,
111
.disabled = false,
112
.next = *plugin_list };
113
114
new_plugin->argv = malloc(sizeof(char *) * 2);
115
if (new_plugin->argv == NULL){
116
free(new_plugin);
117
return NULL;
118
}
119
new_plugin->argv[0] = name;
120
new_plugin->argv[1] = NULL;
121
122
new_plugin->environ = malloc(sizeof(char *));
123
if(new_plugin->environ == NULL){
124
free(new_plugin->argv);
125
free(new_plugin);
126
return NULL;
127
}
128
new_plugin->environ[0] = NULL;
129
/* Append the new plugin to the list */
130
*plugin_list = new_plugin;
131
return new_plugin;
132
}
133
134
/* Helper function for add_argument and add_environment */
135
static bool add_to_char_array(const char *new, char ***array,
136
int *len){
137
/* Resize the pointed-to array to hold one more pointer */
138
*array = realloc(*array, sizeof(char *)
139
* (size_t) ((*len) + 2));
140
/* Malloc check */
141
if(*array == NULL){
142
return false;
143
}
144
/* Make a copy of the new string */
145
char *copy = strdup(new);
146
if(copy == NULL){
147
return false;
148
}
149
/* Insert the copy */
150
(*array)[*len] = copy;
151
(*len)++;
152
/* Add a new terminating NULL pointer to the last element */
153
(*array)[*len] = NULL;
154
return true;
155
}
156
157
/* Add to a plugin's argument vector */
158
static bool add_argument(plugin *p, const char *arg){
159
if(p == NULL){
160
return false;
161
}
162
return add_to_char_array(arg, &(p->argv), &(p->argc));
163
}
164
165
/* Add to a plugin's environment */
166
static bool add_environment(plugin *p, const char *def){
167
if(p == NULL){
168
return false;
169
}
170
return add_to_char_array(def, &(p->environ), &(p->envc));
171
}
172
173
174
/*
175
* Based on the example in the GNU LibC manual chapter 13.13 "File
176
* Descriptor Flags".
177
* *Note File Descriptor Flags:(libc)Descriptor Flags.
178
*/
179
static int set_cloexec_flag(int fd)
180
{
181
int ret = fcntl(fd, F_GETFD, 0);
182
/* If reading the flags failed, return error indication now. */
183
if(ret < 0){
184
return ret;
185
}
186
/* Store modified flag word in the descriptor. */
187
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
188
}
189
190
process *process_list = NULL;
191
192
/* Mark a process as completed when it exits, and save its exit
193
status. */
194
void handle_sigchld(__attribute__((unused)) int sig){
195
process *proc = process_list;
196
int status;
197
pid_t pid = wait(&status);
198
if(pid == -1){
199
perror("wait");
200
return;
201
}
202
while(proc != NULL and proc->pid != pid){
203
proc = proc->next;
204
}
205
if(proc == NULL){
206
/* Process not found in process list */
207
return;
208
}
209
proc->status = status;
210
proc->completed = true;
211
}
212
213
bool print_out_password(const char *buffer, size_t length){
214
ssize_t ret;
215
if(length>0 and buffer[length-1] == '\n'){
216
length--;
217
}
218
for(size_t written = 0; written < length; written += (size_t)ret){
219
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
220
length - written));
221
if(ret < 0){
222
return false;
223
}
224
}
225
return true;
226
}
227
228
char **add_to_argv(char **argv, int *argc, char *arg){
229
if (argv == NULL){
230
*argc = 1;
231
argv = malloc(sizeof(char*) * 2);
232
if(argv == NULL){
233
return NULL;
234
}
235
argv[0] = NULL; /* Will be set to argv[0] in main before parsing */
236
argv[1] = NULL;
237
}
238
*argc += 1;
239
argv = realloc(argv, sizeof(char *)
240
* ((unsigned int) *argc + 1));
241
if(argv == NULL){
242
return NULL;
243
}
244
argv[*argc-1] = arg;
245
argv[*argc] = NULL;
246
return argv;
247
}
28
248
29
249
int main(int argc, char *argv[]){
30
char plugindir[] = "plugins.d";
31
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
32
DIR *dir;
250
const char *plugindir = "/lib/mandos/plugins.d";
251
const char *argfile = ARGFILE;
252
FILE *conffp;
253
size_t d_name_len;
254
DIR *dir = NULL;
33
255
struct dirent *dirst;
34
256
struct stat st;
35
fd_set rfds_orig;
257
fd_set rfds_all;
36
258
int ret, maxfd = 0;
37
process *process_list = NULL;
259
uid_t uid = 65534;
260
gid_t gid = 65534;
261
bool debug = false;
262
int exitstatus = EXIT_SUCCESS;
263
struct sigaction old_sigchld_action;
264
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
265
.sa_flags = SA_NOCLDSTOP };
266
char **custom_argv = NULL;
267
int custom_argc = 0;
268
269
/* Establish a signal handler */
270
sigemptyset(&sigchld_action.sa_mask);
271
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
272
if(ret < 0){
273
perror("sigaddset");
274
exit(EXIT_FAILURE);
275
}
276
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
277
if(ret < 0){
278
perror("sigaction");
279
exit(EXIT_FAILURE);
280
}
281
282
/* The options we understand. */
283
struct argp_option options[] = {
284
{ .name = "global-options", .key = 'g',
285
.arg = "OPTION[,OPTION[,...]]",
286
.doc = "Options passed to all plugins" },
287
{ .name = "global-envs", .key = 'e',
288
.arg = "VAR=value",
289
.doc = "Environment variable passed to all plugins" },
290
{ .name = "options-for", .key = 'o',
291
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
292
.doc = "Options passed only to specified plugin" },
293
{ .name = "envs-for", .key = 'f',
294
.arg = "PLUGIN:ENV=value",
295
.doc = "Environment variable passed to specified plugin" },
296
{ .name = "disable", .key = 'd',
297
.arg = "PLUGIN",
298
.doc = "Disable a specific plugin", .group = 1 },
299
{ .name = "plugin-dir", .key = 128,
300
.arg = "DIRECTORY",
301
.doc = "Specify a different plugin directory", .group = 2 },
302
{ .name = "userid", .key = 129,
303
.arg = "ID", .flags = 0,
304
.doc = "User ID the plugins will run as", .group = 2 },
305
{ .name = "groupid", .key = 130,
306
.arg = "ID", .flags = 0,
307
.doc = "Group ID the plugins will run as", .group = 2 },
308
{ .name = "debug", .key = 131,
309
.doc = "Debug mode", .group = 3 },
310
{ .name = NULL }
311
};
312
313
error_t parse_opt (int key, char *arg, struct argp_state *state) {
314
/* Get the INPUT argument from `argp_parse', which we know is a
315
pointer to our plugin list pointer. */
316
plugin **plugins = state->input;
317
switch (key) {
318
case 'g':
319
if (arg != NULL){
320
char *p;
321
while((p = strsep(&arg, ",")) != NULL){
322
if(p[0] == '\0'){
323
continue;
324
}
325
if(not add_argument(getplugin(NULL, plugins), p)){
326
perror("add_argument");
327
return ARGP_ERR_UNKNOWN;
328
}
329
}
330
}
331
break;
332
case 'e':
333
if(arg == NULL){
334
break;
335
}
336
{
337
char *envdef = strdup(arg);
338
if(envdef == NULL){
339
break;
340
}
341
if(not add_environment(getplugin(NULL, plugins), envdef)){
342
perror("add_environment");
343
}
344
}
345
break;
346
case 'o':
347
if (arg != NULL){
348
char *p_name = strsep(&arg, ":");
349
if(p_name[0] == '\0'){
350
break;
351
}
352
char *opt = strsep(&arg, ":");
353
if(opt[0] == '\0'){
354
break;
355
}
356
if(opt != NULL){
357
char *p;
358
while((p = strsep(&opt, ",")) != NULL){
359
if(p[0] == '\0'){
360
continue;
361
}
362
if(not add_argument(getplugin(p_name, plugins), p)){
363
perror("add_argument");
364
return ARGP_ERR_UNKNOWN;
365
}
366
}
367
}
368
}
369
break;
370
case 'f':
371
if(arg == NULL){
372
break;
373
}
374
{
375
char *envdef = strchr(arg, ':');
376
if(envdef == NULL){
377
break;
378
}
379
char *p_name = strndup(arg, (size_t) (envdef-arg));
380
if(p_name == NULL){
381
break;
382
}
383
envdef++;
384
if(not add_environment(getplugin(p_name, plugins), envdef)){
385
perror("add_environment");
386
}
387
}
388
break;
389
case 'd':
390
if (arg != NULL){
391
plugin *p = getplugin(arg, plugins);
392
if(p == NULL){
393
return ARGP_ERR_UNKNOWN;
394
}
395
p->disabled = true;
396
}
397
break;
398
case 128:
399
plugindir = arg;
400
break;
401
case 129:
402
uid = (uid_t)strtol(arg, NULL, 10);
403
break;
404
case 130:
405
gid = (gid_t)strtol(arg, NULL, 10);
406
break;
407
case 131:
408
debug = true;
409
break;
410
case ARGP_KEY_ARG:
411
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
412
break;
413
case ARGP_KEY_END:
414
break;
415
default:
416
return ARGP_ERR_UNKNOWN;
417
}
418
return 0;
419
}
420
421
plugin *plugin_list = NULL;
422
423
struct argp argp = { .options = options, .parser = parse_opt,
424
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
425
.doc = "Mandos plugin runner -- Run plugins" };
426
427
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
428
if (ret == ARGP_ERR_UNKNOWN){
429
fprintf(stderr, "Unknown error while parsing arguments\n");
430
exitstatus = EXIT_FAILURE;
431
goto end;
432
}
433
434
conffp = fopen(argfile, "r");
435
if(conffp != NULL){
436
char *org_line = NULL;
437
size_t size = 0;
438
ssize_t sret;
439
char *p, *arg, *new_arg, *line;
440
const char whitespace_delims[] = " \r\t\f\v\n";
441
const char comment_delim[] = "#";
442
443
while(true){
444
sret = getline(&org_line, &size, conffp);
445
if(sret == -1){
446
break;
447
}
448
449
line = org_line;
450
arg = strsep(&line, comment_delim);
451
while((p = strsep(&arg, whitespace_delims)) != NULL){
452
if(p[0] == '\0'){
453
continue;
454
}
455
new_arg = strdup(p);
456
custom_argv = add_to_argv(custom_argv, &custom_argc, new_arg);
457
if (custom_argv == NULL){
458
perror("add_to_argv");
459
exitstatus = EXIT_FAILURE;
460
goto end;
461
}
462
}
463
}
464
free(org_line);
465
} else{
466
/* Check for harmful errors and go to fallback. Other errors might
467
not affect opening plugins */
468
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
469
perror("fopen");
470
exitstatus = EXIT_FAILURE;
471
goto end;
472
}
473
}
474
475
if(custom_argv != NULL){
476
custom_argv[0] = argv[0];
477
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
478
if (ret == ARGP_ERR_UNKNOWN){
479
fprintf(stderr, "Unknown error while parsing arguments\n");
480
exitstatus = EXIT_FAILURE;
481
goto end;
482
}
483
}
484
485
if(debug){
486
for(plugin *p = plugin_list; p != NULL; p=p->next){
487
fprintf(stderr, "Plugin: %s has %d arguments\n",
488
p->name ? p->name : "Global", p->argc - 1);
489
for(char **a = p->argv; *a != NULL; a++){
490
fprintf(stderr, "\tArg: %s\n", *a);
491
}
492
fprintf(stderr, "...and %u environment variables\n", p->envc);
493
for(char **a = p->environ; *a != NULL; a++){
494
fprintf(stderr, "\t%s\n", *a);
495
}
496
}
497
}
498
499
ret = setuid(uid);
500
if (ret == -1){
501
perror("setuid");
502
}
503
504
setgid(gid);
505
if (ret == -1){
506
perror("setgid");
507
}
38
508
39
509
dir = opendir(plugindir);
40
41
510
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
511
perror("Could not open plugin dir");
512
exitstatus = EXIT_FAILURE;
513
goto end;
514
}
515
516
/* Set the FD_CLOEXEC flag on the directory, if possible */
517
{
518
int dir_fd = dirfd(dir);
519
if(dir_fd >= 0){
520
ret = set_cloexec_flag(dir_fd);
521
if(ret < 0){
522
perror("set_cloexec_flag");
523
exitstatus = EXIT_FAILURE;
524
goto end;
525
}
526
}
527
}
528
529
FD_ZERO(&rfds_all);
47
530
48
531
while(true){
49
532
dirst = readdir(dir);
50
533
51
534
// All directory entries have been processed
52
535
if(dirst == NULL){
536
if (errno == EBADF){
537
perror("readdir");
538
exitstatus = EXIT_FAILURE;
539
goto end;
540
}
53
541
break;
54
542
}
55
543
56
544
d_name_len = strlen(dirst->d_name);
57
545
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 */
546
// Ignore dotfiles, backup files and other junk
547
{
548
bool bad_name = false;
549
550
const char const *bad_prefixes[] = { ".", "#", NULL };
551
552
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
553
".dpkg-old",
554
".dpkg-divert", NULL };
555
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
556
size_t pre_len = strlen(*pre);
557
if((d_name_len >= pre_len)
558
and strncmp((dirst->d_name), *pre, pre_len) == 0){
559
if(debug){
560
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
561
" with bad prefix %s\n", dirst->d_name, *pre);
562
}
563
bad_name = true;
564
break;
565
}
566
}
567
568
if(bad_name){
569
continue;
570
}
571
572
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
573
size_t suf_len = strlen(*suf);
574
if((d_name_len >= suf_len)
575
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
576
== 0)){
577
if(debug){
578
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
579
" with bad suffix %s\n", dirst->d_name, *suf);
580
}
581
bad_name = true;
582
break;
583
}
584
}
585
586
if(bad_name){
587
continue;
588
}
589
}
590
591
char *filename;
592
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
593
if(ret < 0){
594
perror("asprintf");
595
continue;
596
}
597
598
ret = stat(filename, &st);
599
if (ret == -1){
600
perror("stat");
601
free(filename);
602
continue;
603
}
604
605
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
606
if(debug){
607
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
608
" with bad type or mode\n", filename);
609
}
610
free(filename);
611
continue;
612
}
613
plugin *p = getplugin(dirst->d_name, &plugin_list);
614
if(p == NULL){
615
perror("getplugin");
616
free(filename);
617
continue;
618
}
619
if(p->disabled){
620
if(debug){
621
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
622
dirst->d_name);
623
}
624
free(filename);
625
continue;
626
}
627
{
628
/* Add global arguments to argument list for this plugin */
629
plugin *g = getplugin(NULL, &plugin_list);
630
if(g != NULL){
631
for(char **a = g->argv + 1; *a != NULL; a++){
632
if(not add_argument(p, *a)){
633
perror("add_argument");
634
}
635
}
636
/* Add global environment variables */
637
for(char **e = g->environ; *e != NULL; e++){
638
if(not add_environment(p, *e)){
639
perror("add_environment");
640
}
641
}
642
}
643
}
644
/* If this plugin has any environment variables, we will call
645
using execve and need to duplicate the environment from this
646
process, too. */
647
if(p->environ[0] != NULL){
648
for(char **e = environ; *e != NULL; e++){
649
char *copy = strdup(*e);
650
if(copy == NULL){
651
perror("strdup");
652
continue;
653
}
654
if(not add_environment(p, copy)){
655
perror("add_environment");
656
}
657
}
658
}
659
660
int pipefd[2];
661
ret = pipe(pipefd);
662
if (ret == -1){
663
perror("pipe");
664
exitstatus = EXIT_FAILURE;
665
goto end;
666
}
667
ret = set_cloexec_flag(pipefd[0]);
668
if(ret < 0){
669
perror("set_cloexec_flag");
670
exitstatus = EXIT_FAILURE;
671
goto end;
672
}
673
ret = set_cloexec_flag(pipefd[1]);
674
if(ret < 0){
675
perror("set_cloexec_flag");
676
exitstatus = EXIT_FAILURE;
677
goto end;
678
}
679
/* Block SIGCHLD until process is safely in process list */
680
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
681
if(ret < 0){
682
perror("sigprocmask");
683
exitstatus = EXIT_FAILURE;
684
goto end;
685
}
686
// Starting a new process to be watched
687
pid_t pid = fork();
688
if(pid == -1){
689
perror("fork");
690
exitstatus = EXIT_FAILURE;
691
goto end;
692
}
693
if(pid == 0){
694
/* this is the child process */
695
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
696
if(ret < 0){
697
perror("sigaction");
698
_exit(EXIT_FAILURE);
699
}
700
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
701
if(ret < 0){
702
perror("sigprocmask");
703
_exit(EXIT_FAILURE);
704
}
705
706
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
707
if(ret == -1){
708
perror("dup2");
709
_exit(EXIT_FAILURE);
710
}
711
712
if(dirfd(dir) < 0){
713
/* If dir has no file descriptor, we could not set FD_CLOEXEC
714
above and must now close it manually here. */
79
715
closedir(dir);
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;
114
}
716
}
717
if(p->environ[0] == NULL){
718
if(execv(filename, p->argv) < 0){
719
perror("execv");
720
_exit(EXIT_FAILURE);
721
}
722
} else {
723
if(execve(filename, p->argv, p->environ) < 0){
724
perror("execve");
725
_exit(EXIT_FAILURE);
726
}
727
}
728
/* no return */
729
}
730
/* parent process */
731
free(filename);
732
close(pipefd[1]); /* close unused write end of pipe */
733
process *new_process = malloc(sizeof(process));
734
if (new_process == NULL){
735
perror("malloc");
736
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
737
if(ret < 0){
738
perror("sigprocmask");
739
}
740
exitstatus = EXIT_FAILURE;
741
goto end;
742
}
743
744
*new_process = (struct process){ .pid = pid,
745
.fd = pipefd[0],
746
.next = process_list };
747
// List handling
748
process_list = new_process;
749
/* Unblock SIGCHLD so signal handler can be run if this process
750
has already completed */
751
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
752
if(ret < 0){
753
perror("sigprocmask");
754
exitstatus = EXIT_FAILURE;
755
goto end;
756
}
757
758
FD_SET(new_process->fd, &rfds_all);
759
760
if (maxfd < new_process->fd){
761
maxfd = new_process->fd;
762
}
763
764
}
765
766
/* Free the plugin list */
767
for(plugin *next; plugin_list != NULL; plugin_list = next){
768
next = plugin_list->next;
769
free(plugin_list->argv);
770
if(plugin_list->environ[0] != NULL){
771
for(char **e = plugin_list->environ; *e != NULL; e++){
772
free(*e);
773
}
774
}
775
free(plugin_list);
115
776
}
116
777
117
778
closedir(dir);
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;
779
dir = NULL;
780
781
if (process_list == NULL){
782
fprintf(stderr, "No plugin processes started. Incorrect plugin"
783
" directory?\n");
784
process_list = NULL;
785
}
786
while(process_list){
787
fd_set rfds = rfds_all;
788
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
789
if (select_ret == -1){
790
perror("select");
791
exitstatus = EXIT_FAILURE;
792
goto end;
793
}
794
/* OK, now either a process completed, or something can be read
795
from one of them */
796
for(process *proc = process_list; proc ; proc = proc->next){
797
/* Is this process completely done? */
798
if(proc->eof and proc->completed){
799
/* Only accept the plugin output if it exited cleanly */
800
if(not WIFEXITED(proc->status)
801
or WEXITSTATUS(proc->status) != 0){
802
/* Bad exit by plugin */
803
if(debug){
804
if(WIFEXITED(proc->status)){
805
fprintf(stderr, "Plugin %u exited with status %d\n",
806
(unsigned int) (proc->pid),
807
WEXITSTATUS(proc->status));
808
} else if(WIFSIGNALED(proc->status)) {
809
fprintf(stderr, "Plugin %u killed by signal %d\n",
810
(unsigned int) (proc->pid),
811
WTERMSIG(proc->status));
812
} else if(WCOREDUMP(proc->status)){
813
fprintf(stderr, "Plugin %d dumped core\n",
814
(unsigned int) (proc->pid));
140
815
}
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);
816
}
817
/* Remove the plugin */
818
FD_CLR(proc->fd, &rfds_all);
819
/* Block signal while modifying process_list */
820
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
821
if(ret < 0){
822
perror("sigprocmask");
823
exitstatus = EXIT_FAILURE;
824
goto end;
825
}
826
/* Delete this process entry from the list */
827
if(process_list == proc){
828
/* First one - simple */
829
process_list = proc->next;
830
} else {
831
/* Second one or later */
832
for(process *p = process_list; p != NULL; p = p->next){
833
if(p->next == proc){
834
p->next = proc->next;
835
break;
155
836
}
156
837
}
157
838
}
158
}
839
/* We are done modifying process list, so unblock signal */
840
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
841
NULL);
842
if(ret < 0){
843
perror("sigprocmask");
844
}
845
free(proc->buffer);
846
free(proc);
847
/* We deleted this process from the list, so we can't go
848
proc->next. Therefore, start over from the beginning of
849
the process list */
850
break;
851
}
852
/* This process exited nicely, so print its buffer */
853
854
bool bret = print_out_password(proc->buffer, proc->buffer_length);
855
if(not bret){
856
perror("print_out_password");
857
exitstatus = EXIT_FAILURE;
858
}
859
goto end;
860
}
861
/* This process has not completed. Does it have any output? */
862
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
863
/* This process had nothing to say at this time */
864
continue;
865
}
866
/* Before reading, make the process' data buffer large enough */
867
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
868
proc->buffer = realloc(proc->buffer, proc->buffer_size
869
+ (size_t) BUFFER_SIZE);
870
if (proc->buffer == NULL){
871
perror("malloc");
872
exitstatus = EXIT_FAILURE;
873
goto end;
874
}
875
proc->buffer_size += BUFFER_SIZE;
876
}
877
/* Read from the process */
878
ret = read(proc->fd, proc->buffer + proc->buffer_length,
879
BUFFER_SIZE);
880
if(ret < 0){
881
/* Read error from this process; ignore the error */
882
continue;
883
}
884
if(ret == 0){
885
/* got EOF */
886
proc->eof = true;
887
} else {
888
proc->buffer_length += (size_t) ret;
159
889
}
160
890
}
161
891
}
162
892
893
163
894
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);
895
896
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
897
/* Fallback if all plugins failed, none are found or an error occured */
898
bool bret;
899
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
900
char *passwordbuffer = getpass("Password: ");
901
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
902
if(not bret){
903
perror("print_out_password");
904
exitstatus = EXIT_FAILURE;
905
goto end;
906
}
169
907
}
170
908
171
while(true){
172
int status;
173
ret = wait(&status);
174
if (ret == -1){
175
if(errno != ECHILD){
176
perror("wait");
909
/* Restore old signal handler */
910
sigaction(SIGCHLD, &old_sigchld_action, NULL);
911
912
free(custom_argv);
913
914
/* Free the plugin list */
915
for(plugin *next; plugin_list != NULL; plugin_list = next){
916
next = plugin_list->next;
917
free(plugin_list->argv);
918
if(plugin_list->environ[0] != NULL){
919
for(char **e = plugin_list->environ; *e != NULL; e++){
920
free(*e);
177
921
}
178
break;
179
}
180
}
181
return EXIT_SUCCESS;
922
}
923
free(plugin_list->environ);
924
free(plugin_list);
925
}
926
927
if(dir != NULL){
928
closedir(dir);
929
}
930
931
/* Free the process list and kill the processes */
932
for(process *next; process_list != NULL; process_list = next){
933
next = process_list->next;
934
close(process_list->fd);
935
ret = kill(process_list->pid, SIGTERM);
936
if(ret == -1 and errno != ESRCH){
937
/* set-uid proccesses migth not get closed */
938
perror("kill");
939
}
940
free(process_list->buffer);
941
free(process_list);
942
}
943
944
/* Wait for any remaining child processes to terminate */
945
do{
946
ret = wait(NULL);
947
} while(ret >= 0);
948
if(errno != ECHILD){
949
perror("wait");
950
}
951
952
return exitstatus;
182
953
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0