To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/release
« back to all changes in this revision
Viewing changes to plugin-runner.c
- browse files at revision 163
- compare with another revision
- download diff
- download tarball
- view history from revision 163
- Committer: Teddy Hogeborn
- Date: 2008-09-05 16:24:33 UTC
- Revision ID: teddy@fukt.bsnet.se-20080905162433-58fgx91ae9foxlh1
* Makefile (PIDDIR, USER, GROUP): Removed.
(install-server): Do not create $(PIDDIR).
(uninstall-server): Do not remove $(PIDDIR).
* init.d-mandos (PIDFILE): Changed to "/var/run/$NAME.pid".
* mandos (IPv6_TCPServer.enabled): New attribute.
(IPv6_TCPServer.server_activate): Only call method of superclass if
"self.enabled".
(IPv6_TCPServer.enable): Set "self.enabled" to True.
(main): Create client Set() early. Create IPv6_TCPServer object
early. Switch to user and group "mandos", "nobody" or
65534, if possible. Enable IPv6_TCPServer *after* switching
user.
* mandos-keygen (KEYDIR): Changed to "/etc/keys/mandos".
* mandos.xml (FILES): Changed PID file.
(SECURITY): The server does need to be privileged, but switches to a
non-privileged user.
* plugin-runner.xml (EXAMPLE): Changed long example to something more
realistic.
(install-server): Do not create $(PIDDIR).
(uninstall-server): Do not remove $(PIDDIR).
* init.d-mandos (PIDFILE): Changed to "/var/run/$NAME.pid".
* mandos (IPv6_TCPServer.enabled): New attribute.
(IPv6_TCPServer.server_activate): Only call method of superclass if
"self.enabled".
(IPv6_TCPServer.enable): Set "self.enabled" to True.
(main): Create client Set() early. Create IPv6_TCPServer object
early. Switch to user and group "mandos", "nobody" or
65534, if possible. Enable IPv6_TCPServer *after* switching
user.
* mandos-keygen (KEYDIR): Changed to "/etc/keys/mandos".
* mandos.xml (FILES): Changed PID file.
(SECURITY): The server does need to be privileged, but switches to a
non-privileged user.
* plugin-runner.xml (EXAMPLE): Changed long example to something more
realistic.
- files added:
- .bzrignore
- 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 */
15
16
struct process;
17
18
typedef struct process{
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*/
19
86
pid_t pid;
20
87
int fd;
21
88
char *buffer;
22
int buffer_size;
23
int buffer_length;
24
struct process *next;
25
} process;
26
27
#define BUFFER_SIZE 256
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, bool replace){
183
if(p == NULL){
184
return false;
185
}
186
/* namelen = length of name of environment variable */
187
size_t namelen = (size_t)(strchrnul(def, '=') - def);
188
/* Search for this environment variable */
189
for(char **e = p->environ; *e != NULL; e++){
190
if(strncmp(*e, def, namelen+1) == 0){
191
/* It already exists */
192
if(replace){
193
char *new = realloc(*e, strlen(def));
194
if(new == NULL){
195
return false;
196
}
197
*e = new;
198
strcpy(*e, def);
199
}
200
return true;
201
}
202
}
203
return add_to_char_array(def, &(p->environ), &(p->envc));
204
}
205
206
/*
207
* Based on the example in the GNU LibC manual chapter 13.13 "File
208
* Descriptor Flags".
209
* *Note File Descriptor Flags:(libc)Descriptor Flags.
210
*/
211
static int set_cloexec_flag(int fd)
212
{
213
int ret = fcntl(fd, F_GETFD, 0);
214
/* If reading the flags failed, return error indication now. */
215
if(ret < 0){
216
return ret;
217
}
218
/* Store modified flag word in the descriptor. */
219
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
220
}
221
222
223
/* Mark processes as completed when they exit, and save their exit
224
status. */
225
void handle_sigchld(__attribute__((unused)) int sig){
226
while(true){
227
plugin *proc = plugin_list;
228
int status;
229
pid_t pid = waitpid(-1, &status, WNOHANG);
230
if(pid == 0){
231
/* Only still running child processes */
232
break;
233
}
234
if(pid == -1){
235
if (errno != ECHILD){
236
perror("waitpid");
237
}
238
/* No child processes */
239
break;
240
}
241
242
/* A child exited, find it in process_list */
243
while(proc != NULL and proc->pid != pid){
244
proc = proc->next;
245
}
246
if(proc == NULL){
247
/* Process not found in process list */
248
continue;
249
}
250
proc->status = status;
251
proc->completed = true;
252
}
253
}
254
255
/* Prints out a password to stdout */
256
bool print_out_password(const char *buffer, size_t length){
257
ssize_t ret;
258
if(length>0 and buffer[length-1] == '\n'){
259
length--;
260
}
261
for(size_t written = 0; written < length; written += (size_t)ret){
262
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
263
length - written));
264
if(ret < 0){
265
return false;
266
}
267
}
268
return true;
269
}
270
271
/* Removes and free a plugin from the plugin list */
272
static void free_plugin(plugin *plugin_node){
273
274
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
275
free(*arg);
276
}
277
free(plugin_node->argv);
278
for(char **env = plugin_node->environ; *env != NULL; env++){
279
free(*env);
280
}
281
free(plugin_node->environ);
282
free(plugin_node->buffer);
283
284
/* Removes the plugin from the singly-linked list */
285
if(plugin_node == plugin_list){
286
/* First one - simple */
287
plugin_list = plugin_list->next;
288
} else {
289
/* Second one or later */
290
for(plugin *p = plugin_list; p != NULL; p = p->next){
291
if(p->next == plugin_node){
292
p->next = plugin_node->next;
293
break;
294
}
295
}
296
}
297
298
free(plugin_node);
299
}
300
301
static void free_plugin_list(void){
302
while(plugin_list != NULL){
303
free_plugin(plugin_list);
304
}
305
}
28
306
29
307
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;
308
char *plugindir = NULL;
309
char *argfile = NULL;
310
FILE *conffp;
311
size_t d_name_len;
312
DIR *dir = NULL;
33
313
struct dirent *dirst;
34
314
struct stat st;
35
fd_set rfds_orig;
315
fd_set rfds_all;
36
316
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
317
uid_t uid = 65534;
318
gid_t gid = 65534;
319
bool debug = false;
320
int exitstatus = EXIT_SUCCESS;
321
struct sigaction old_sigchld_action;
322
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
323
.sa_flags = SA_NOCLDSTOP };
324
char **custom_argv = NULL;
325
int custom_argc = 0;
326
327
/* Establish a signal handler */
328
sigemptyset(&sigchld_action.sa_mask);
329
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
330
if(ret == -1){
331
perror("sigaddset");
332
exitstatus = EXIT_FAILURE;
333
goto fallback;
334
}
335
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
336
if(ret == -1){
337
perror("sigaction");
338
exitstatus = EXIT_FAILURE;
339
goto fallback;
340
}
341
342
/* The options we understand. */
343
struct argp_option options[] = {
344
{ .name = "global-options", .key = 'g',
345
.arg = "OPTION[,OPTION[,...]]",
346
.doc = "Options passed to all plugins" },
347
{ .name = "global-env", .key = 'G',
348
.arg = "VAR=value",
349
.doc = "Environment variable passed to all plugins" },
350
{ .name = "options-for", .key = 'o',
351
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
352
.doc = "Options passed only to specified plugin" },
353
{ .name = "env-for", .key = 'E',
354
.arg = "PLUGIN:ENV=value",
355
.doc = "Environment variable passed to specified plugin" },
356
{ .name = "disable", .key = 'd',
357
.arg = "PLUGIN",
358
.doc = "Disable a specific plugin", .group = 1 },
359
{ .name = "enable", .key = 'e',
360
.arg = "PLUGIN",
361
.doc = "Enable a specific plugin", .group = 1 },
362
{ .name = "plugin-dir", .key = 128,
363
.arg = "DIRECTORY",
364
.doc = "Specify a different plugin directory", .group = 2 },
365
{ .name = "config-file", .key = 129,
366
.arg = "FILE",
367
.doc = "Specify a different configuration file", .group = 2 },
368
{ .name = "userid", .key = 130,
369
.arg = "ID", .flags = 0,
370
.doc = "User ID the plugins will run as", .group = 3 },
371
{ .name = "groupid", .key = 131,
372
.arg = "ID", .flags = 0,
373
.doc = "Group ID the plugins will run as", .group = 3 },
374
{ .name = "debug", .key = 132,
375
.doc = "Debug mode", .group = 4 },
376
{ .name = NULL }
377
};
378
379
error_t parse_opt (int key, char *arg, __attribute__((unused))
380
struct argp_state *state) {
381
switch (key) {
382
case 'g': /* --global-options */
383
if (arg != NULL){
384
char *p;
385
while((p = strsep(&arg, ",")) != NULL){
386
if(p[0] == '\0'){
387
continue;
388
}
389
if(not add_argument(getplugin(NULL), p)){
390
perror("add_argument");
391
return ARGP_ERR_UNKNOWN;
392
}
393
}
394
}
395
break;
396
case 'G': /* --global-env */
397
if(arg == NULL){
398
break;
399
}
400
{
401
char *envdef = strdup(arg);
402
if(envdef == NULL){
403
break;
404
}
405
if(not add_environment(getplugin(NULL), envdef, true)){
406
perror("add_environment");
407
}
408
}
409
break;
410
case 'o': /* --options-for */
411
if (arg != NULL){
412
char *p_name = strsep(&arg, ":");
413
if(p_name[0] == '\0'){
414
break;
415
}
416
char *opt = strsep(&arg, ":");
417
if(opt[0] == '\0'){
418
break;
419
}
420
if(opt != NULL){
421
char *p;
422
while((p = strsep(&opt, ",")) != NULL){
423
if(p[0] == '\0'){
424
continue;
425
}
426
if(not add_argument(getplugin(p_name), p)){
427
perror("add_argument");
428
return ARGP_ERR_UNKNOWN;
429
}
430
}
431
}
432
}
433
break;
434
case 'E': /* --env-for */
435
if(arg == NULL){
436
break;
437
}
438
{
439
char *envdef = strchr(arg, ':');
440
if(envdef == NULL){
441
break;
442
}
443
char *p_name = strndup(arg, (size_t) (envdef-arg));
444
if(p_name == NULL){
445
break;
446
}
447
envdef++;
448
if(not add_environment(getplugin(p_name), envdef, true)){
449
perror("add_environment");
450
}
451
}
452
break;
453
case 'd': /* --disable */
454
if (arg != NULL){
455
plugin *p = getplugin(arg);
456
if(p == NULL){
457
return ARGP_ERR_UNKNOWN;
458
}
459
p->disabled = true;
460
}
461
break;
462
case 'e': /* --enable */
463
if (arg != NULL){
464
plugin *p = getplugin(arg);
465
if(p == NULL){
466
return ARGP_ERR_UNKNOWN;
467
}
468
p->disabled = false;
469
}
470
break;
471
case 128: /* --plugin-dir */
472
plugindir = strdup(arg);
473
if(plugindir == NULL){
474
perror("strdup");
475
}
476
break;
477
case 129: /* --config-file */
478
/* This is already done by parse_opt_config_file() */
479
break;
480
case 130: /* --userid */
481
uid = (uid_t)strtol(arg, NULL, 10);
482
break;
483
case 131: /* --groupid */
484
gid = (gid_t)strtol(arg, NULL, 10);
485
break;
486
case 132: /* --debug */
487
debug = true;
488
break;
489
case ARGP_KEY_ARG:
490
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
491
break;
492
case ARGP_KEY_END:
493
break;
494
default:
495
return ARGP_ERR_UNKNOWN;
496
}
497
return 0;
498
}
499
500
/* This option parser is the same as parse_opt() above, except it
501
ignores everything but the --config-file option. */
502
error_t parse_opt_config_file (int key, char *arg,
503
__attribute__((unused))
504
struct argp_state *state) {
505
switch (key) {
506
case 'g': /* --global-options */
507
case 'G': /* --global-env */
508
case 'o': /* --options-for */
509
case 'E': /* --env-for */
510
case 'd': /* --disable */
511
case 'e': /* --enable */
512
case 128: /* --plugin-dir */
513
break;
514
case 129: /* --config-file */
515
argfile = strdup(arg);
516
if(argfile == NULL){
517
perror("strdup");
518
}
519
break;
520
case 130: /* --userid */
521
case 131: /* --groupid */
522
case 132: /* --debug */
523
case ARGP_KEY_ARG:
524
case ARGP_KEY_END:
525
break;
526
default:
527
return ARGP_ERR_UNKNOWN;
528
}
529
return 0;
530
}
531
532
struct argp argp = { .options = options,
533
.parser = parse_opt_config_file,
534
.args_doc = "",
535
.doc = "Mandos plugin runner -- Run plugins" };
536
537
/* Parse using the parse_opt_config_file in order to get the custom
538
config file location, if any. */
539
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
540
if (ret == ARGP_ERR_UNKNOWN){
541
fprintf(stderr, "Unknown error while parsing arguments\n");
542
exitstatus = EXIT_FAILURE;
543
goto fallback;
544
}
545
546
/* Reset to the normal argument parser */
547
argp.parser = parse_opt;
548
549
/* Open the configfile if available */
550
if (argfile == NULL){
551
conffp = fopen(AFILE, "r");
552
} else {
553
conffp = fopen(argfile, "r");
554
}
555
if(conffp != NULL){
556
char *org_line = NULL;
557
char *p, *arg, *new_arg, *line;
558
size_t size = 0;
559
ssize_t sret;
560
const char whitespace_delims[] = " \r\t\f\v\n";
561
const char comment_delim[] = "#";
562
563
custom_argc = 1;
564
custom_argv = malloc(sizeof(char*) * 2);
565
if(custom_argv == NULL){
566
perror("malloc");
567
exitstatus = EXIT_FAILURE;
568
goto fallback;
569
}
570
custom_argv[0] = argv[0];
571
custom_argv[1] = NULL;
572
573
/* for each line in the config file, strip whitespace and ignore
574
commented text */
575
while(true){
576
sret = getline(&org_line, &size, conffp);
577
if(sret == -1){
578
break;
579
}
580
581
line = org_line;
582
arg = strsep(&line, comment_delim);
583
while((p = strsep(&arg, whitespace_delims)) != NULL){
584
if(p[0] == '\0'){
585
continue;
586
}
587
new_arg = strdup(p);
588
if(new_arg == NULL){
589
perror("strdup");
590
exitstatus = EXIT_FAILURE;
591
free(org_line);
592
goto fallback;
593
}
594
595
custom_argc += 1;
596
custom_argv = realloc(custom_argv, sizeof(char *)
597
* ((unsigned int) custom_argc + 1));
598
if(custom_argv == NULL){
599
perror("realloc");
600
exitstatus = EXIT_FAILURE;
601
free(org_line);
602
goto fallback;
603
}
604
custom_argv[custom_argc-1] = new_arg;
605
custom_argv[custom_argc] = NULL;
606
}
607
}
608
free(org_line);
609
} else {
610
/* Check for harmful errors and go to fallback. Other errors might
611
not affect opening plugins */
612
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
613
perror("fopen");
614
exitstatus = EXIT_FAILURE;
615
goto fallback;
616
}
617
}
618
/* If there was any arguments from configuration file,
619
pass them to parser as command arguments */
620
if(custom_argv != NULL){
621
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
622
0, NULL);
623
if (ret == ARGP_ERR_UNKNOWN){
624
fprintf(stderr, "Unknown error while parsing arguments\n");
625
exitstatus = EXIT_FAILURE;
626
goto fallback;
627
}
628
}
629
630
/* Parse actual command line arguments, to let them override the
631
config file */
632
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
633
if (ret == ARGP_ERR_UNKNOWN){
634
fprintf(stderr, "Unknown error while parsing arguments\n");
635
exitstatus = EXIT_FAILURE;
636
goto fallback;
637
}
638
639
if(debug){
640
for(plugin *p = plugin_list; p != NULL; p=p->next){
641
fprintf(stderr, "Plugin: %s has %d arguments\n",
642
p->name ? p->name : "Global", p->argc - 1);
643
for(char **a = p->argv; *a != NULL; a++){
644
fprintf(stderr, "\tArg: %s\n", *a);
645
}
646
fprintf(stderr, "...and %u environment variables\n", p->envc);
647
for(char **a = p->environ; *a != NULL; a++){
648
fprintf(stderr, "\t%s\n", *a);
649
}
650
}
651
}
652
653
/* Strip permissions down to nobody */
654
ret = setuid(uid);
655
if (ret == -1){
656
perror("setuid");
657
}
658
setgid(gid);
659
if (ret == -1){
660
perror("setgid");
661
}
662
663
if (plugindir == NULL){
664
dir = opendir(PDIR);
665
} else {
666
dir = opendir(plugindir);
667
}
668
41
669
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
670
perror("Could not open plugin dir");
671
exitstatus = EXIT_FAILURE;
672
goto fallback;
673
}
674
675
/* Set the FD_CLOEXEC flag on the directory, if possible */
676
{
677
int dir_fd = dirfd(dir);
678
if(dir_fd >= 0){
679
ret = set_cloexec_flag(dir_fd);
680
if(ret < 0){
681
perror("set_cloexec_flag");
682
exitstatus = EXIT_FAILURE;
683
goto fallback;
684
}
685
}
686
}
687
688
FD_ZERO(&rfds_all);
689
690
/* Read and execute any executable in the plugin directory*/
48
691
while(true){
49
692
dirst = readdir(dir);
50
693
51
// All directory entries have been processed
694
/* All directory entries have been processed */
52
695
if(dirst == NULL){
696
if (errno == EBADF){
697
perror("readdir");
698
exitstatus = EXIT_FAILURE;
699
goto fallback;
700
}
53
701
break;
54
702
}
55
703
56
704
d_name_len = strlen(dirst->d_name);
57
705
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 */
706
/* Ignore dotfiles, backup files and other junk */
707
{
708
bool bad_name = false;
709
710
const char const *bad_prefixes[] = { ".", "#", NULL };
711
712
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
713
".dpkg-old",
714
".dpkg-divert", NULL };
715
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
716
size_t pre_len = strlen(*pre);
717
if((d_name_len >= pre_len)
718
and strncmp((dirst->d_name), *pre, pre_len) == 0){
719
if(debug){
720
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
721
" with bad prefix %s\n", dirst->d_name, *pre);
722
}
723
bad_name = true;
724
break;
725
}
726
}
727
if(bad_name){
728
continue;
729
}
730
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
731
size_t suf_len = strlen(*suf);
732
if((d_name_len >= suf_len)
733
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
734
== 0)){
735
if(debug){
736
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
737
" with bad suffix %s\n", dirst->d_name, *suf);
738
}
739
bad_name = true;
740
break;
741
}
742
}
743
744
if(bad_name){
745
continue;
746
}
747
}
748
749
char *filename;
750
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
751
if(ret < 0){
752
perror("asprintf");
753
continue;
754
}
755
756
ret = stat(filename, &st);
757
if (ret == -1){
758
perror("stat");
759
free(filename);
760
continue;
761
}
762
763
/* Ignore non-executable files */
764
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
765
if(debug){
766
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
767
" with bad type or mode\n", filename);
768
}
769
free(filename);
770
continue;
771
}
772
773
plugin *p = getplugin(dirst->d_name);
774
if(p == NULL){
775
perror("getplugin");
776
free(filename);
777
continue;
778
}
779
if(p->disabled){
780
if(debug){
781
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
782
dirst->d_name);
783
}
784
free(filename);
785
continue;
786
}
787
{
788
/* Add global arguments to argument list for this plugin */
789
plugin *g = getplugin(NULL);
790
if(g != NULL){
791
for(char **a = g->argv + 1; *a != NULL; a++){
792
if(not add_argument(p, *a)){
793
perror("add_argument");
794
}
795
}
796
/* Add global environment variables */
797
for(char **e = g->environ; *e != NULL; e++){
798
if(not add_environment(p, *e, false)){
799
perror("add_environment");
800
}
801
}
802
}
803
}
804
/* If this plugin has any environment variables, we will call
805
using execve and need to duplicate the environment from this
806
process, too. */
807
if(p->environ[0] != NULL){
808
for(char **e = environ; *e != NULL; e++){
809
if(not add_environment(p, *e, false)){
810
perror("add_environment");
811
}
812
}
813
}
814
815
int pipefd[2];
816
ret = pipe(pipefd);
817
if (ret == -1){
818
perror("pipe");
819
exitstatus = EXIT_FAILURE;
820
goto fallback;
821
}
822
/* Ask OS to automatic close the pipe on exec */
823
ret = set_cloexec_flag(pipefd[0]);
824
if(ret < 0){
825
perror("set_cloexec_flag");
826
exitstatus = EXIT_FAILURE;
827
goto fallback;
828
}
829
ret = set_cloexec_flag(pipefd[1]);
830
if(ret < 0){
831
perror("set_cloexec_flag");
832
exitstatus = EXIT_FAILURE;
833
goto fallback;
834
}
835
/* Block SIGCHLD until process is safely in process list */
836
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
837
if(ret < 0){
838
perror("sigprocmask");
839
exitstatus = EXIT_FAILURE;
840
goto fallback;
841
}
842
/* Starting a new process to be watched */
843
pid_t pid = fork();
844
if(pid == -1){
845
perror("fork");
846
exitstatus = EXIT_FAILURE;
847
goto fallback;
848
}
849
if(pid == 0){
850
/* this is the child process */
851
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
852
if(ret < 0){
853
perror("sigaction");
854
_exit(EXIT_FAILURE);
855
}
856
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
857
if(ret < 0){
858
perror("sigprocmask");
859
_exit(EXIT_FAILURE);
860
}
861
862
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
863
if(ret == -1){
864
perror("dup2");
865
_exit(EXIT_FAILURE);
866
}
867
868
if(dirfd(dir) < 0){
869
/* If dir has no file descriptor, we could not set FD_CLOEXEC
870
above and must now close it manually here. */
79
871
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
}
872
}
873
if(p->environ[0] == NULL){
874
if(execv(filename, p->argv) < 0){
875
perror("execv");
876
_exit(EXIT_FAILURE);
877
}
878
} else {
879
if(execve(filename, p->argv, p->environ) < 0){
880
perror("execve");
881
_exit(EXIT_FAILURE);
882
}
883
}
884
/* no return */
885
}
886
/* Parent process */
887
close(pipefd[1]); /* Close unused write end of pipe */
888
free(filename);
889
plugin *new_plugin = getplugin(dirst->d_name);
890
if (new_plugin == NULL){
891
perror("getplugin");
892
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
893
if(ret < 0){
894
perror("sigprocmask");
895
}
896
exitstatus = EXIT_FAILURE;
897
goto fallback;
898
}
899
900
new_plugin->pid = pid;
901
new_plugin->fd = pipefd[0];
902
903
/* Unblock SIGCHLD so signal handler can be run if this process
904
has already completed */
905
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
906
if(ret < 0){
907
perror("sigprocmask");
908
exitstatus = EXIT_FAILURE;
909
goto fallback;
910
}
911
912
FD_SET(new_plugin->fd, &rfds_all);
913
914
if (maxfd < new_plugin->fd){
915
maxfd = new_plugin->fd;
916
}
917
115
918
}
116
919
117
920
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;
140
}
141
ret = read(process_itr->fd, process_itr->buffer
142
+ process_itr->buffer_length, BUFFER_SIZE);
143
process_itr->buffer_length+=ret;
144
if(ret == 0){
145
/* got EOF */
146
/* wait for process exit */
147
int status;
148
waitpid(process_itr->pid, &status, 0);
149
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
150
write(STDOUT_FILENO, process_itr->buffer,
151
process_itr->buffer_length);
152
goto end;
153
} else {
154
FD_CLR(process_itr->fd, &rfds_orig);
155
}
156
}
157
}
158
}
159
}
160
}
161
}
162
163
end:
164
for(process *process_itr = process_list; process_itr != NULL;
165
process_itr = process_itr->next){
166
close(process_itr->fd);
167
kill(process_itr->pid, SIGTERM);
168
free(process_itr->buffer);
169
}
170
171
while(true){
172
int status;
173
ret = wait(&status);
174
if (ret == -1){
175
if(errno != ECHILD){
176
perror("wait");
177
}
921
dir = NULL;
922
923
for(plugin *p = plugin_list; p != NULL; p = p->next){
924
if(p->pid != 0){
178
925
break;
179
926
}
180
}
181
return EXIT_SUCCESS;
927
if(p->next == NULL){
928
fprintf(stderr, "No plugin processes started. Incorrect plugin"
929
" directory?\n");
930
free_plugin_list();
931
}
932
}
933
934
/* Main loop while running plugins exist */
935
while(plugin_list){
936
fd_set rfds = rfds_all;
937
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
938
if (select_ret == -1){
939
perror("select");
940
exitstatus = EXIT_FAILURE;
941
goto fallback;
942
}
943
/* OK, now either a process completed, or something can be read
944
from one of them */
945
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
946
/* Is this process completely done? */
947
if(proc->eof and proc->completed){
948
/* Only accept the plugin output if it exited cleanly */
949
if(not WIFEXITED(proc->status)
950
or WEXITSTATUS(proc->status) != 0){
951
/* Bad exit by plugin */
952
953
if(debug){
954
if(WIFEXITED(proc->status)){
955
fprintf(stderr, "Plugin %u exited with status %d\n",
956
(unsigned int) (proc->pid),
957
WEXITSTATUS(proc->status));
958
} else if(WIFSIGNALED(proc->status)) {
959
fprintf(stderr, "Plugin %u killed by signal %d\n",
960
(unsigned int) (proc->pid),
961
WTERMSIG(proc->status));
962
} else if(WCOREDUMP(proc->status)){
963
fprintf(stderr, "Plugin %d dumped core\n",
964
(unsigned int) (proc->pid));
965
}
966
}
967
968
/* Remove the plugin */
969
FD_CLR(proc->fd, &rfds_all);
970
971
/* Block signal while modifying process_list */
972
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
973
if(ret < 0){
974
perror("sigprocmask");
975
exitstatus = EXIT_FAILURE;
976
goto fallback;
977
}
978
free_plugin(proc);
979
/* We are done modifying process list, so unblock signal */
980
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
981
NULL);
982
if(ret < 0){
983
perror("sigprocmask");
984
exitstatus = EXIT_FAILURE;
985
goto fallback;
986
}
987
988
if(plugin_list == NULL){
989
break;
990
}
991
continue;
992
}
993
994
/* This process exited nicely, so print its buffer */
995
996
bool bret = print_out_password(proc->buffer,
997
proc->buffer_length);
998
if(not bret){
999
perror("print_out_password");
1000
exitstatus = EXIT_FAILURE;
1001
}
1002
goto fallback;
1003
}
1004
1005
/* This process has not completed. Does it have any output? */
1006
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1007
/* This process had nothing to say at this time */
1008
continue;
1009
}
1010
/* Before reading, make the process' data buffer large enough */
1011
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1012
proc->buffer = realloc(proc->buffer, proc->buffer_size
1013
+ (size_t) BUFFER_SIZE);
1014
if (proc->buffer == NULL){
1015
perror("malloc");
1016
exitstatus = EXIT_FAILURE;
1017
goto fallback;
1018
}
1019
proc->buffer_size += BUFFER_SIZE;
1020
}
1021
/* Read from the process */
1022
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1023
BUFFER_SIZE);
1024
if(ret < 0){
1025
/* Read error from this process; ignore the error */
1026
continue;
1027
}
1028
if(ret == 0){
1029
/* got EOF */
1030
proc->eof = true;
1031
} else {
1032
proc->buffer_length += (size_t) ret;
1033
}
1034
}
1035
}
1036
1037
1038
fallback:
1039
1040
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1041
/* Fallback if all plugins failed, none are found or an error
1042
occured */
1043
bool bret;
1044
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1045
char *passwordbuffer = getpass("Password: ");
1046
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1047
if(not bret){
1048
perror("print_out_password");
1049
exitstatus = EXIT_FAILURE;
1050
}
1051
}
1052
1053
/* Restore old signal handler */
1054
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1055
if(ret == -1){
1056
perror("sigaction");
1057
exitstatus = EXIT_FAILURE;
1058
}
1059
1060
if(custom_argv != NULL){
1061
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1062
free(*arg);
1063
}
1064
free(custom_argv);
1065
}
1066
1067
if(dir != NULL){
1068
closedir(dir);
1069
}
1070
1071
/* Free the process list and kill the processes */
1072
for(plugin *p = plugin_list; p != NULL; p = p->next){
1073
if(p->pid != 0){
1074
close(p->fd);
1075
ret = kill(p->pid, SIGTERM);
1076
if(ret == -1 and errno != ESRCH){
1077
/* Set-uid proccesses might not get closed */
1078
perror("kill");
1079
}
1080
}
1081
}
1082
1083
/* Wait for any remaining child processes to terminate */
1084
do{
1085
ret = wait(NULL);
1086
} while(ret >= 0);
1087
if(errno != ECHILD){
1088
perror("wait");
1089
}
1090
1091
free_plugin_list();
1092
1093
free(plugindir);
1094
free(argfile);
1095
1096
return exitstatus;
182
1097
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0