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- Committer: Björn Påhlsson
- Date: 2009-02-09 18:15:18 UTC
- mto: (24.1.154 mandos) (237.4.3 mandos-release)
- mto: This revision was merged to the branch mainline in revision 309.
- Revision ID: belorn@braxen-20090209181518-powtql91qv3wu51d
Earlier signal handling
- files added:
- .bzr-builddeb
- debian
- debian/po
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- plugbasedclient.c => plugin-runner.c
- plugins.d/mandosclient.c => plugins.d/mandos-client.c
- plugins.d/passprompt.c => plugins.d/password-prompt.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 © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
7
*
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
12
*
13
* This program is distributed in the hope that it will be useful, but
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16
* General Public License for more details.
17
*
18
* You should have received a copy of the GNU General Public License
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
21
*
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
*/
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf() */
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
EXIT_SUCCESS, realloc() */
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
36
uid_t, gid_t, getuid(), getgid(),
37
dirfd() */
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
FD_SET(), FD_ISSET(), FD_CLR */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS() */
42
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
readdir(), closedir(), dirfd() */
46
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
47
fcntl(), setuid(), setgid(),
48
F_GETFD, F_SETFD, FD_CLOEXEC,
49
access(), pipe(), fork(), close()
50
dup2(), STDOUT_FILENO, _exit(),
51
execv(), write(), read(),
52
close() */
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
FD_CLOEXEC */
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <errno.h> /* errno */
57
#include <argp.h> /* struct argp_option, struct
58
argp_state, struct argp,
59
argp_parse(), ARGP_ERR_UNKNOWN,
60
ARGP_KEY_END, ARGP_KEY_ARG,
61
error_t */
62
#include <signal.h> /* struct sigaction, sigemptyset(),
63
sigaddset(), sigaction(),
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
65
SIG_UNBLOCK, kill() */
66
#include <errno.h> /* errno, EBADF */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
68
69
#define BUFFER_SIZE 256
70
71
#define PDIR "/lib/mandos/plugins.d"
72
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
73
74
const char *argp_program_version = "plugin-runner " VERSION;
75
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
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 sig_atomic_t completed;
93
int status;
94
struct plugin *next;
95
} plugin;
96
97
static plugin *plugin_list = NULL;
98
99
/* Gets an 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
free(new_plugin);
119
return NULL;
120
}
121
}
122
123
*new_plugin = (plugin){ .name = copy_name,
124
.argc = 1,
125
.disabled = false,
126
.next = plugin_list };
127
128
new_plugin->argv = malloc(sizeof(char *) * 2);
129
if(new_plugin->argv == NULL){
130
free(copy_name);
131
free(new_plugin);
132
return NULL;
133
}
134
new_plugin->argv[0] = copy_name;
135
new_plugin->argv[1] = NULL;
136
137
new_plugin->environ = malloc(sizeof(char *));
138
if(new_plugin->environ == NULL){
139
free(copy_name);
140
free(new_plugin->argv);
141
free(new_plugin);
142
return NULL;
143
}
144
new_plugin->environ[0] = NULL;
145
146
/* Append the new plugin to the list */
147
plugin_list = new_plugin;
148
return new_plugin;
149
}
150
151
/* Helper function for add_argument and add_environment */
152
static bool add_to_char_array(const char *new, char ***array,
153
int *len){
154
/* Resize the pointed-to array to hold one more pointer */
155
*array = realloc(*array, sizeof(char *)
156
* (size_t) ((*len) + 2));
157
/* Malloc check */
158
if(*array == NULL){
159
return false;
160
}
161
/* Make a copy of the new string */
162
char *copy = strdup(new);
163
if(copy == NULL){
164
return false;
165
}
166
/* Insert the copy */
167
(*array)[*len] = copy;
168
(*len)++;
169
/* Add a new terminating NULL pointer to the last element */
170
(*array)[*len] = NULL;
171
return true;
172
}
173
174
/* Add to a plugin's argument vector */
175
static bool add_argument(plugin *p, const char *arg){
176
if(p == NULL){
177
return false;
178
}
179
return add_to_char_array(arg, &(p->argv), &(p->argc));
180
}
181
182
/* Add to a plugin's environment */
183
static bool add_environment(plugin *p, const char *def, bool replace){
184
if(p == NULL){
185
return false;
186
}
187
/* namelen = length of name of environment variable */
188
size_t namelen = (size_t)(strchrnul(def, '=') - def);
189
/* Search for this environment variable */
190
for(char **e = p->environ; *e != NULL; e++){
191
if(strncmp(*e, def, namelen + 1) == 0){
192
/* It already exists */
193
if(replace){
194
char *new = realloc(*e, strlen(def) + 1);
195
if(new == NULL){
196
return false;
197
}
198
*e = new;
199
strcpy(*e, def);
200
}
201
return true;
202
}
203
}
204
return add_to_char_array(def, &(p->environ), &(p->envc));
205
}
206
207
/*
208
* Based on the example in the GNU LibC manual chapter 13.13 "File
209
* Descriptor Flags".
210
* *Note File Descriptor Flags:(libc)Descriptor Flags.
211
*/
212
static int set_cloexec_flag(int fd){
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
static void handle_sigchld(__attribute__((unused)) int sig){
226
int old_errno = errno;
227
while(true){
228
plugin *proc = plugin_list;
229
int status;
230
pid_t pid = waitpid(-1, &status, WNOHANG);
231
if(pid == 0){
232
/* Only still running child processes */
233
break;
234
}
235
if(pid == -1){
236
if(errno == ECHILD){
237
/* No child processes */
238
break;
239
}
240
perror("waitpid");
241
}
242
243
/* A child exited, find it in process_list */
244
while(proc != NULL and proc->pid != pid){
245
proc = proc->next;
246
}
247
if(proc == NULL){
248
/* Process not found in process list */
249
continue;
250
}
251
proc->status = status;
252
proc->completed = 1;
253
}
254
errno = old_errno;
255
}
256
257
/* Prints out a password to stdout */
258
static bool print_out_password(const char *buffer, size_t length){
259
ssize_t ret;
260
for(size_t written = 0; written < length; written += (size_t)ret){
261
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
262
length - written));
263
if(ret < 0){
264
return false;
265
}
266
}
267
return true;
268
}
269
270
/* Removes and free a plugin from the plugin list */
271
static void free_plugin(plugin *plugin_node){
272
273
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
274
free(*arg);
275
}
276
free(plugin_node->argv);
277
for(char **env = plugin_node->environ; *env != NULL; env++){
278
free(*env);
279
}
280
free(plugin_node->environ);
281
free(plugin_node->buffer);
282
283
/* Removes the plugin from the singly-linked list */
284
if(plugin_node == plugin_list){
285
/* First one - simple */
286
plugin_list = plugin_list->next;
287
} else {
288
/* Second one or later */
289
for(plugin *p = plugin_list; p != NULL; p = p->next){
290
if(p->next == plugin_node){
291
p->next = plugin_node->next;
292
break;
293
}
294
}
295
}
296
297
free(plugin_node);
298
}
299
300
static void free_plugin_list(void){
301
while(plugin_list != NULL){
302
free_plugin(plugin_list);
303
}
304
}
28
305
29
306
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;
307
char *plugindir = NULL;
308
char *argfile = NULL;
309
FILE *conffp;
310
size_t d_name_len;
311
DIR *dir = NULL;
33
312
struct dirent *dirst;
34
313
struct stat st;
35
fd_set rfds_orig;
36
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
314
fd_set rfds_all;
315
int ret, numchars, maxfd = 0;
316
ssize_t sret;
317
intmax_t tmpmax;
318
uid_t uid = 65534;
319
gid_t gid = 65534;
320
bool debug = false;
321
int exitstatus = EXIT_SUCCESS;
322
struct sigaction old_sigchld_action;
323
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
324
.sa_flags = SA_NOCLDSTOP };
325
char **custom_argv = NULL;
326
int custom_argc = 0;
327
328
/* Establish a signal handler */
329
sigemptyset(&sigchld_action.sa_mask);
330
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
331
if(ret == -1){
332
perror("sigaddset");
333
exitstatus = EXIT_FAILURE;
334
goto fallback;
335
}
336
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
337
if(ret == -1){
338
perror("sigaction");
339
exitstatus = EXIT_FAILURE;
340
goto fallback;
341
}
342
343
/* The options we understand. */
344
struct argp_option options[] = {
345
{ .name = "global-options", .key = 'g',
346
.arg = "OPTION[,OPTION[,...]]",
347
.doc = "Options passed to all plugins" },
348
{ .name = "global-env", .key = 'G',
349
.arg = "VAR=value",
350
.doc = "Environment variable passed to all plugins" },
351
{ .name = "options-for", .key = 'o',
352
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
353
.doc = "Options passed only to specified plugin" },
354
{ .name = "env-for", .key = 'E',
355
.arg = "PLUGIN:ENV=value",
356
.doc = "Environment variable passed to specified plugin" },
357
{ .name = "disable", .key = 'd',
358
.arg = "PLUGIN",
359
.doc = "Disable a specific plugin", .group = 1 },
360
{ .name = "enable", .key = 'e',
361
.arg = "PLUGIN",
362
.doc = "Enable a specific plugin", .group = 1 },
363
{ .name = "plugin-dir", .key = 128,
364
.arg = "DIRECTORY",
365
.doc = "Specify a different plugin directory", .group = 2 },
366
{ .name = "config-file", .key = 129,
367
.arg = "FILE",
368
.doc = "Specify a different configuration file", .group = 2 },
369
{ .name = "userid", .key = 130,
370
.arg = "ID", .flags = 0,
371
.doc = "User ID the plugins will run as", .group = 3 },
372
{ .name = "groupid", .key = 131,
373
.arg = "ID", .flags = 0,
374
.doc = "Group ID the plugins will run as", .group = 3 },
375
{ .name = "debug", .key = 132,
376
.doc = "Debug mode", .group = 4 },
377
{ .name = NULL }
378
};
379
380
error_t parse_opt(int key, char *arg, __attribute__((unused))
381
struct argp_state *state){
382
switch(key){
383
case 'g': /* --global-options */
384
if(arg != NULL){
385
char *plugin_option;
386
while((plugin_option = strsep(&arg, ",")) != NULL){
387
if(plugin_option[0] == '\0'){
388
continue;
389
}
390
if(not add_argument(getplugin(NULL), plugin_option)){
391
perror("add_argument");
392
return ARGP_ERR_UNKNOWN;
393
}
394
}
395
}
396
break;
397
case 'G': /* --global-env */
398
if(arg == NULL){
399
break;
400
}
401
if(not add_environment(getplugin(NULL), arg, true)){
402
perror("add_environment");
403
}
404
break;
405
case 'o': /* --options-for */
406
if(arg != NULL){
407
char *plugin_name = strsep(&arg, ":");
408
if(plugin_name[0] == '\0'){
409
break;
410
}
411
char *plugin_option;
412
while((plugin_option = strsep(&arg, ",")) != NULL){
413
if(not add_argument(getplugin(plugin_name), plugin_option)){
414
perror("add_argument");
415
return ARGP_ERR_UNKNOWN;
416
}
417
}
418
}
419
break;
420
case 'E': /* --env-for */
421
if(arg == NULL){
422
break;
423
}
424
{
425
char *envdef = strchr(arg, ':');
426
if(envdef == NULL){
427
break;
428
}
429
*envdef = '\0';
430
if(not add_environment(getplugin(arg), envdef+1, true)){
431
perror("add_environment");
432
}
433
}
434
break;
435
case 'd': /* --disable */
436
if(arg != NULL){
437
plugin *p = getplugin(arg);
438
if(p == NULL){
439
return ARGP_ERR_UNKNOWN;
440
}
441
p->disabled = true;
442
}
443
break;
444
case 'e': /* --enable */
445
if(arg != NULL){
446
plugin *p = getplugin(arg);
447
if(p == NULL){
448
return ARGP_ERR_UNKNOWN;
449
}
450
p->disabled = false;
451
}
452
break;
453
case 128: /* --plugin-dir */
454
free(plugindir);
455
plugindir = strdup(arg);
456
if(plugindir == NULL){
457
perror("strdup");
458
}
459
break;
460
case 129: /* --config-file */
461
/* This is already done by parse_opt_config_file() */
462
break;
463
case 130: /* --userid */
464
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
465
if(ret < 1 or tmpmax != (uid_t)tmpmax
466
or arg[numchars] != '\0'){
467
fprintf(stderr, "Bad user ID number: \"%s\", using %"
468
PRIdMAX "\n", arg, (intmax_t)uid);
469
} else {
470
uid = (uid_t)tmpmax;
471
}
472
break;
473
case 131: /* --groupid */
474
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
475
if(ret < 1 or tmpmax != (gid_t)tmpmax
476
or arg[numchars] != '\0'){
477
fprintf(stderr, "Bad group ID number: \"%s\", using %"
478
PRIdMAX "\n", arg, (intmax_t)gid);
479
} else {
480
gid = (gid_t)tmpmax;
481
}
482
break;
483
case 132: /* --debug */
484
debug = true;
485
break;
486
/*
487
* When adding more options before this line, remember to also add a
488
* "case" to the "parse_opt_config_file" function below.
489
*/
490
case ARGP_KEY_ARG:
491
/* Cryptsetup always passes an argument, which is an empty
492
string if "none" was specified in /etc/crypttab. So if
493
argument was empty, we ignore it silently. */
494
if(arg[0] != '\0'){
495
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
496
}
497
break;
498
case ARGP_KEY_END:
499
break;
500
default:
501
return ARGP_ERR_UNKNOWN;
502
}
503
return 0;
504
}
505
506
/* This option parser is the same as parse_opt() above, except it
507
ignores everything but the --config-file option. */
508
error_t parse_opt_config_file(int key, char *arg,
509
__attribute__((unused))
510
struct argp_state *state){
511
switch(key){
512
case 'g': /* --global-options */
513
case 'G': /* --global-env */
514
case 'o': /* --options-for */
515
case 'E': /* --env-for */
516
case 'd': /* --disable */
517
case 'e': /* --enable */
518
case 128: /* --plugin-dir */
519
break;
520
case 129: /* --config-file */
521
free(argfile);
522
argfile = strdup(arg);
523
if(argfile == NULL){
524
perror("strdup");
525
}
526
break;
527
case 130: /* --userid */
528
case 131: /* --groupid */
529
case 132: /* --debug */
530
case ARGP_KEY_ARG:
531
case ARGP_KEY_END:
532
break;
533
default:
534
return ARGP_ERR_UNKNOWN;
535
}
536
return 0;
537
}
538
539
struct argp argp = { .options = options,
540
.parser = parse_opt_config_file,
541
.args_doc = "",
542
.doc = "Mandos plugin runner -- Run plugins" };
543
544
/* Parse using parse_opt_config_file() in order to get the custom
545
config file location, if any. */
546
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
547
if(ret == ARGP_ERR_UNKNOWN){
548
fprintf(stderr, "Unknown error while parsing arguments\n");
549
exitstatus = EXIT_FAILURE;
550
goto fallback;
551
}
552
553
/* Reset to the normal argument parser */
554
argp.parser = parse_opt;
555
556
/* Open the configfile if available */
557
if(argfile == NULL){
558
conffp = fopen(AFILE, "r");
559
} else {
560
conffp = fopen(argfile, "r");
561
}
562
if(conffp != NULL){
563
char *org_line = NULL;
564
char *p, *arg, *new_arg, *line;
565
size_t size = 0;
566
const char whitespace_delims[] = " \r\t\f\v\n";
567
const char comment_delim[] = "#";
568
569
custom_argc = 1;
570
custom_argv = malloc(sizeof(char*) * 2);
571
if(custom_argv == NULL){
572
perror("malloc");
573
exitstatus = EXIT_FAILURE;
574
goto fallback;
575
}
576
custom_argv[0] = argv[0];
577
custom_argv[1] = NULL;
578
579
/* for each line in the config file, strip whitespace and ignore
580
commented text */
581
while(true){
582
sret = getline(&org_line, &size, conffp);
583
if(sret == -1){
584
break;
585
}
586
587
line = org_line;
588
arg = strsep(&line, comment_delim);
589
while((p = strsep(&arg, whitespace_delims)) != NULL){
590
if(p[0] == '\0'){
591
continue;
592
}
593
new_arg = strdup(p);
594
if(new_arg == NULL){
595
perror("strdup");
596
exitstatus = EXIT_FAILURE;
597
free(org_line);
598
goto fallback;
599
}
600
601
custom_argc += 1;
602
custom_argv = realloc(custom_argv, sizeof(char *)
603
* ((unsigned int) custom_argc + 1));
604
if(custom_argv == NULL){
605
perror("realloc");
606
exitstatus = EXIT_FAILURE;
607
free(org_line);
608
goto fallback;
609
}
610
custom_argv[custom_argc-1] = new_arg;
611
custom_argv[custom_argc] = NULL;
612
}
613
}
614
free(org_line);
615
} else {
616
/* Check for harmful errors and go to fallback. Other errors might
617
not affect opening plugins */
618
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
619
perror("fopen");
620
exitstatus = EXIT_FAILURE;
621
goto fallback;
622
}
623
}
624
/* If there was any arguments from configuration file,
625
pass them to parser as command arguments */
626
if(custom_argv != NULL){
627
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
628
0, NULL);
629
if(ret == ARGP_ERR_UNKNOWN){
630
fprintf(stderr, "Unknown error while parsing arguments\n");
631
exitstatus = EXIT_FAILURE;
632
goto fallback;
633
}
634
}
635
636
/* Parse actual command line arguments, to let them override the
637
config file */
638
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
639
if(ret == ARGP_ERR_UNKNOWN){
640
fprintf(stderr, "Unknown error while parsing arguments\n");
641
exitstatus = EXIT_FAILURE;
642
goto fallback;
643
}
644
645
if(debug){
646
for(plugin *p = plugin_list; p != NULL; p=p->next){
647
fprintf(stderr, "Plugin: %s has %d arguments\n",
648
p->name ? p->name : "Global", p->argc - 1);
649
for(char **a = p->argv; *a != NULL; a++){
650
fprintf(stderr, "\tArg: %s\n", *a);
651
}
652
fprintf(stderr, "...and %d environment variables\n", p->envc);
653
for(char **a = p->environ; *a != NULL; a++){
654
fprintf(stderr, "\t%s\n", *a);
655
}
656
}
657
}
658
659
/* Strip permissions down to nobody */
660
setgid(gid);
661
if(ret == -1){
662
perror("setgid");
663
}
664
ret = setuid(uid);
665
if(ret == -1){
666
perror("setuid");
667
}
668
669
if(plugindir == NULL){
670
dir = opendir(PDIR);
671
} else {
672
dir = opendir(plugindir);
673
}
674
41
675
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
676
perror("Could not open plugin dir");
677
exitstatus = EXIT_FAILURE;
678
goto fallback;
679
}
680
681
/* Set the FD_CLOEXEC flag on the directory, if possible */
682
{
683
int dir_fd = dirfd(dir);
684
if(dir_fd >= 0){
685
ret = set_cloexec_flag(dir_fd);
686
if(ret < 0){
687
perror("set_cloexec_flag");
688
exitstatus = EXIT_FAILURE;
689
goto fallback;
690
}
691
}
692
}
693
694
FD_ZERO(&rfds_all);
695
696
/* Read and execute any executable in the plugin directory*/
48
697
while(true){
49
698
dirst = readdir(dir);
50
699
51
// All directory entries have been processed
700
/* All directory entries have been processed */
52
701
if(dirst == NULL){
702
if(errno == EBADF){
703
perror("readdir");
704
exitstatus = EXIT_FAILURE;
705
goto fallback;
706
}
53
707
break;
54
708
}
55
709
56
710
d_name_len = strlen(dirst->d_name);
57
711
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 + 2);
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 */
712
/* Ignore dotfiles, backup files and other junk */
713
{
714
bool bad_name = false;
715
716
const char const *bad_prefixes[] = { ".", "#", NULL };
717
718
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
719
".dpkg-old",
720
".dpkg-bak",
721
".dpkg-divert", NULL };
722
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
723
size_t pre_len = strlen(*pre);
724
if((d_name_len >= pre_len)
725
and strncmp((dirst->d_name), *pre, pre_len) == 0){
726
if(debug){
727
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
728
" with bad prefix %s\n", dirst->d_name, *pre);
729
}
730
bad_name = true;
731
break;
732
}
733
}
734
if(bad_name){
735
continue;
736
}
737
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
738
size_t suf_len = strlen(*suf);
739
if((d_name_len >= suf_len)
740
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
741
== 0)){
742
if(debug){
743
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
744
" with bad suffix %s\n", dirst->d_name, *suf);
745
}
746
bad_name = true;
747
break;
748
}
749
}
750
751
if(bad_name){
752
continue;
753
}
754
}
755
756
char *filename;
757
if(plugindir == NULL){
758
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
759
} else {
760
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
761
}
762
if(ret < 0){
763
perror("asprintf");
764
continue;
765
}
766
767
ret = stat(filename, &st);
768
if(ret == -1){
769
perror("stat");
770
free(filename);
771
continue;
772
}
773
774
/* Ignore non-executable files */
775
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
776
if(debug){
777
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
778
" with bad type or mode\n", filename);
779
}
780
free(filename);
781
continue;
782
}
783
784
plugin *p = getplugin(dirst->d_name);
785
if(p == NULL){
786
perror("getplugin");
787
free(filename);
788
continue;
789
}
790
if(p->disabled){
791
if(debug){
792
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
793
dirst->d_name);
794
}
795
free(filename);
796
continue;
797
}
798
{
799
/* Add global arguments to argument list for this plugin */
800
plugin *g = getplugin(NULL);
801
if(g != NULL){
802
for(char **a = g->argv + 1; *a != NULL; a++){
803
if(not add_argument(p, *a)){
804
perror("add_argument");
805
}
806
}
807
/* Add global environment variables */
808
for(char **e = g->environ; *e != NULL; e++){
809
if(not add_environment(p, *e, false)){
810
perror("add_environment");
811
}
812
}
813
}
814
}
815
/* If this plugin has any environment variables, we will call
816
using execve and need to duplicate the environment from this
817
process, too. */
818
if(p->environ[0] != NULL){
819
for(char **e = environ; *e != NULL; e++){
820
if(not add_environment(p, *e, false)){
821
perror("add_environment");
822
}
823
}
824
}
825
826
int pipefd[2];
827
ret = pipe(pipefd);
828
if(ret == -1){
829
perror("pipe");
830
exitstatus = EXIT_FAILURE;
831
goto fallback;
832
}
833
/* Ask OS to automatic close the pipe on exec */
834
ret = set_cloexec_flag(pipefd[0]);
835
if(ret < 0){
836
perror("set_cloexec_flag");
837
exitstatus = EXIT_FAILURE;
838
goto fallback;
839
}
840
ret = set_cloexec_flag(pipefd[1]);
841
if(ret < 0){
842
perror("set_cloexec_flag");
843
exitstatus = EXIT_FAILURE;
844
goto fallback;
845
}
846
/* Block SIGCHLD until process is safely in process list */
847
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
848
if(ret < 0){
849
perror("sigprocmask");
850
exitstatus = EXIT_FAILURE;
851
goto fallback;
852
}
853
/* Starting a new process to be watched */
854
pid_t pid = fork();
855
if(pid == -1){
856
perror("fork");
857
exitstatus = EXIT_FAILURE;
858
goto fallback;
859
}
860
if(pid == 0){
861
/* this is the child process */
862
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
863
if(ret < 0){
864
perror("sigaction");
865
_exit(EXIT_FAILURE);
866
}
867
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
868
if(ret < 0){
869
perror("sigprocmask");
870
_exit(EXIT_FAILURE);
871
}
872
873
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
874
if(ret == -1){
875
perror("dup2");
876
_exit(EXIT_FAILURE);
877
}
878
879
if(dirfd(dir) < 0){
880
/* If dir has no file descriptor, we could not set FD_CLOEXEC
881
above and must now close it manually here. */
79
882
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;
883
}
884
if(p->environ[0] == NULL){
885
if(execv(filename, p->argv) < 0){
886
perror("execv");
887
_exit(EXIT_FAILURE);
888
}
889
} else {
890
if(execve(filename, p->argv, p->environ) < 0){
891
perror("execve");
892
_exit(EXIT_FAILURE);
893
}
894
}
895
/* no return */
896
}
897
/* Parent process */
898
close(pipefd[1]); /* Close unused write end of pipe */
899
free(filename);
900
plugin *new_plugin = getplugin(dirst->d_name);
901
if(new_plugin == NULL){
902
perror("getplugin");
903
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
904
if(ret < 0){
905
perror("sigprocmask");
906
}
907
exitstatus = EXIT_FAILURE;
908
goto fallback;
909
}
910
911
new_plugin->pid = pid;
912
new_plugin->fd = pipefd[0];
913
914
/* Unblock SIGCHLD so signal handler can be run if this process
915
has already completed */
916
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
917
if(ret < 0){
918
perror("sigprocmask");
919
exitstatus = EXIT_FAILURE;
920
goto fallback;
921
}
922
923
FD_SET(new_plugin->fd, &rfds_all);
924
925
if(maxfd < new_plugin->fd){
926
maxfd = new_plugin->fd;
114
927
}
115
928
}
116
929
117
930
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
}
931
dir = NULL;
932
free_plugin(getplugin(NULL));
933
934
for(plugin *p = plugin_list; p != NULL; p = p->next){
935
if(p->pid != 0){
178
936
break;
179
937
}
180
}
181
return EXIT_SUCCESS;
938
if(p->next == NULL){
939
fprintf(stderr, "No plugin processes started. Incorrect plugin"
940
" directory?\n");
941
free_plugin_list();
942
}
943
}
944
945
/* Main loop while running plugins exist */
946
while(plugin_list){
947
fd_set rfds = rfds_all;
948
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
949
if(select_ret == -1){
950
perror("select");
951
exitstatus = EXIT_FAILURE;
952
goto fallback;
953
}
954
/* OK, now either a process completed, or something can be read
955
from one of them */
956
for(plugin *proc = plugin_list; proc != NULL;){
957
/* Is this process completely done? */
958
if(proc->completed and proc->eof){
959
/* Only accept the plugin output if it exited cleanly */
960
if(not WIFEXITED(proc->status)
961
or WEXITSTATUS(proc->status) != 0){
962
/* Bad exit by plugin */
963
964
if(debug){
965
if(WIFEXITED(proc->status)){
966
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
967
" status %d\n", proc->name,
968
(intmax_t) (proc->pid),
969
WEXITSTATUS(proc->status));
970
} else if(WIFSIGNALED(proc->status)){
971
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
972
" signal %d\n", proc->name,
973
(intmax_t) (proc->pid),
974
WTERMSIG(proc->status));
975
} else if(WCOREDUMP(proc->status)){
976
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
977
" core\n", proc->name, (intmax_t) (proc->pid));
978
}
979
}
980
981
/* Remove the plugin */
982
FD_CLR(proc->fd, &rfds_all);
983
984
/* Block signal while modifying process_list */
985
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
986
if(ret < 0){
987
perror("sigprocmask");
988
exitstatus = EXIT_FAILURE;
989
goto fallback;
990
}
991
992
plugin *next_plugin = proc->next;
993
free_plugin(proc);
994
proc = next_plugin;
995
996
/* We are done modifying process list, so unblock signal */
997
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
998
NULL);
999
if(ret < 0){
1000
perror("sigprocmask");
1001
exitstatus = EXIT_FAILURE;
1002
goto fallback;
1003
}
1004
1005
if(plugin_list == NULL){
1006
break;
1007
}
1008
1009
continue;
1010
}
1011
1012
/* This process exited nicely, so print its buffer */
1013
1014
bool bret = print_out_password(proc->buffer,
1015
proc->buffer_length);
1016
if(not bret){
1017
perror("print_out_password");
1018
exitstatus = EXIT_FAILURE;
1019
}
1020
goto fallback;
1021
}
1022
1023
/* This process has not completed. Does it have any output? */
1024
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1025
/* This process had nothing to say at this time */
1026
proc = proc->next;
1027
continue;
1028
}
1029
/* Before reading, make the process' data buffer large enough */
1030
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1031
proc->buffer = realloc(proc->buffer, proc->buffer_size
1032
+ (size_t) BUFFER_SIZE);
1033
if(proc->buffer == NULL){
1034
perror("malloc");
1035
exitstatus = EXIT_FAILURE;
1036
goto fallback;
1037
}
1038
proc->buffer_size += BUFFER_SIZE;
1039
}
1040
/* Read from the process */
1041
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1042
BUFFER_SIZE);
1043
if(sret < 0){
1044
/* Read error from this process; ignore the error */
1045
proc = proc->next;
1046
continue;
1047
}
1048
if(sret == 0){
1049
/* got EOF */
1050
proc->eof = true;
1051
} else {
1052
proc->buffer_length += (size_t) sret;
1053
}
1054
}
1055
}
1056
1057
1058
fallback:
1059
1060
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1061
/* Fallback if all plugins failed, none are found or an error
1062
occured */
1063
bool bret;
1064
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1065
char *passwordbuffer = getpass("Password: ");
1066
size_t len = strlen(passwordbuffer);
1067
/* Strip trailing newline */
1068
if(len > 0 and passwordbuffer[len-1] == '\n'){
1069
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1070
len--;
1071
}
1072
bret = print_out_password(passwordbuffer, len);
1073
if(not bret){
1074
perror("print_out_password");
1075
exitstatus = EXIT_FAILURE;
1076
}
1077
}
1078
1079
/* Restore old signal handler */
1080
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1081
if(ret == -1){
1082
perror("sigaction");
1083
exitstatus = EXIT_FAILURE;
1084
}
1085
1086
if(custom_argv != NULL){
1087
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1088
free(*arg);
1089
}
1090
free(custom_argv);
1091
}
1092
1093
if(dir != NULL){
1094
closedir(dir);
1095
}
1096
1097
/* Kill the processes */
1098
for(plugin *p = plugin_list; p != NULL; p = p->next){
1099
if(p->pid != 0){
1100
close(p->fd);
1101
ret = kill(p->pid, SIGTERM);
1102
if(ret == -1 and errno != ESRCH){
1103
/* Set-uid proccesses might not get closed */
1104
perror("kill");
1105
}
1106
}
1107
}
1108
1109
/* Wait for any remaining child processes to terminate */
1110
do{
1111
ret = wait(NULL);
1112
} while(ret >= 0);
1113
if(errno != ECHILD){
1114
perror("wait");
1115
}
1116
1117
free_plugin_list();
1118
1119
free(plugindir);
1120
free(argfile);
1121
1122
return exitstatus;
182
1123
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0