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- Committer: Teddy Hogeborn
- Date: 2009-02-07 04:50:39 UTC
- Revision ID: teddy@fukt.bsnet.se-20090207045039-xkr6b80vtqwqrq8l
* Makefile (install-client-nokey): Move "initramfs-tools-script" from
"/scripts/local-top/mandos" to
"/scripts/init-premount/mandos".
(uninstall-client): - '' -
* debian/mandos-client.dirs: - '' -
* initramfs-tools-script (PREREQ): Added "udev".
"/scripts/local-top/mandos" to
"/scripts/init-premount/mandos".
(uninstall-client): - '' -
* debian/mandos-client.dirs: - '' -
* initramfs-tools-script (PREREQ): Added "udev".
- 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
2
2
/*
3
3
* Mandos plugin runner - Run Mandos plugins
4
4
*
5
* Copyright © 2007-2008 Teddy Hogeborn and Björn Påhlsson.
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
6
7
*
7
8
* This program is free software: you can redistribute it and/or
8
9
* modify it under the terms of the GNU General Public License as
18
19
* along with this program. If not, see
19
20
* <http://www.gnu.org/licenses/>.
20
21
*
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
23
23
*/
24
24
25
#define _FORTIFY_SOURCE 2
26
27
#include <stdio.h> /* popen, fileno */
28
#include <iso646.h> /* and, or, not */
29
#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
30
WIFEXITED, WEXITSTATUS, wait */
31
#include <sys/wait.h> /* wait */
32
#include <dirent.h> /* DIR, opendir */
33
#include <sys/stat.h> /* stat, struct stat */
34
#include <unistd.h> /* stat, struct stat, chdir */
35
#include <stdlib.h> /* EXIT_FAILURE */
36
#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET,
37
FD_ISSET */
38
#include <string.h> /* strlen, strcpy, strcat */
39
#include <stdbool.h> /* true */
40
#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
41
#include <errno.h> /* errno */
42
43
struct process;
44
45
typedef struct process{
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*/
46
86
pid_t pid;
47
87
int fd;
48
88
char *buffer;
49
89
size_t buffer_size;
50
90
size_t buffer_length;
51
struct process *next;
52
} process;
53
54
#define BUFFER_SIZE 256
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
}
55
305
56
306
int main(int argc, char *argv[]){
57
char plugindir[] = "plugins.d";
58
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
59
DIR *dir;
307
char *plugindir = NULL;
308
char *argfile = NULL;
309
FILE *conffp;
310
size_t d_name_len;
311
DIR *dir = NULL;
60
312
struct dirent *dirst;
61
313
struct stat st;
62
fd_set rfds_orig;
63
int ret, maxfd = 0;
64
process *process_list = NULL;
65
66
dir = opendir(plugindir);
67
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 *p;
386
while((p = strsep(&arg, ",")) != NULL){
387
if(p[0] == '\0'){
388
continue;
389
}
390
if(not add_argument(getplugin(NULL), p)){
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 *p_name = strsep(&arg, ":");
408
if(p_name[0] == '\0' or arg == NULL){
409
break;
410
}
411
char *opt = strsep(&arg, ":");
412
if(opt[0] == '\0' or opt == NULL){
413
break;
414
}
415
char *p;
416
while((p = strsep(&opt, ",")) != NULL){
417
if(p[0] == '\0'){
418
continue;
419
}
420
if(not add_argument(getplugin(p_name), p)){
421
perror("add_argument");
422
return ARGP_ERR_UNKNOWN;
423
}
424
}
425
}
426
break;
427
case 'E': /* --env-for */
428
if(arg == NULL){
429
break;
430
}
431
{
432
char *envdef = strchr(arg, ':');
433
if(envdef == NULL){
434
break;
435
}
436
*envdef = '\0';
437
if(not add_environment(getplugin(arg), envdef+1, true)){
438
perror("add_environment");
439
}
440
}
441
break;
442
case 'd': /* --disable */
443
if(arg != NULL){
444
plugin *p = getplugin(arg);
445
if(p == NULL){
446
return ARGP_ERR_UNKNOWN;
447
}
448
p->disabled = true;
449
}
450
break;
451
case 'e': /* --enable */
452
if(arg != NULL){
453
plugin *p = getplugin(arg);
454
if(p == NULL){
455
return ARGP_ERR_UNKNOWN;
456
}
457
p->disabled = false;
458
}
459
break;
460
case 128: /* --plugin-dir */
461
free(plugindir);
462
plugindir = strdup(arg);
463
if(plugindir == NULL){
464
perror("strdup");
465
}
466
break;
467
case 129: /* --config-file */
468
/* This is already done by parse_opt_config_file() */
469
break;
470
case 130: /* --userid */
471
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
472
if(ret < 1 or tmpmax != (uid_t)tmpmax
473
or arg[numchars] != '\0'){
474
fprintf(stderr, "Bad user ID number: \"%s\", using %"
475
PRIdMAX "\n", arg, (intmax_t)uid);
476
} else {
477
uid = (uid_t)tmpmax;
478
}
479
break;
480
case 131: /* --groupid */
481
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
482
if(ret < 1 or tmpmax != (gid_t)tmpmax
483
or arg[numchars] != '\0'){
484
fprintf(stderr, "Bad group ID number: \"%s\", using %"
485
PRIdMAX "\n", arg, (intmax_t)gid);
486
} else {
487
gid = (gid_t)tmpmax;
488
}
489
break;
490
case 132: /* --debug */
491
debug = true;
492
break;
493
/*
494
* When adding more options before this line, remember to also add a
495
* "case" to the "parse_opt_config_file" function below.
496
*/
497
case ARGP_KEY_ARG:
498
/* Cryptsetup always passes an argument, which is an empty
499
string if "none" was specified in /etc/crypttab. So if
500
argument was empty, we ignore it silently. */
501
if(arg[0] != '\0'){
502
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
503
}
504
break;
505
case ARGP_KEY_END:
506
break;
507
default:
508
return ARGP_ERR_UNKNOWN;
509
}
510
return 0;
511
}
512
513
/* This option parser is the same as parse_opt() above, except it
514
ignores everything but the --config-file option. */
515
error_t parse_opt_config_file(int key, char *arg,
516
__attribute__((unused))
517
struct argp_state *state){
518
switch(key){
519
case 'g': /* --global-options */
520
case 'G': /* --global-env */
521
case 'o': /* --options-for */
522
case 'E': /* --env-for */
523
case 'd': /* --disable */
524
case 'e': /* --enable */
525
case 128: /* --plugin-dir */
526
break;
527
case 129: /* --config-file */
528
free(argfile);
529
argfile = strdup(arg);
530
if(argfile == NULL){
531
perror("strdup");
532
}
533
break;
534
case 130: /* --userid */
535
case 131: /* --groupid */
536
case 132: /* --debug */
537
case ARGP_KEY_ARG:
538
case ARGP_KEY_END:
539
break;
540
default:
541
return ARGP_ERR_UNKNOWN;
542
}
543
return 0;
544
}
545
546
struct argp argp = { .options = options,
547
.parser = parse_opt_config_file,
548
.args_doc = "",
549
.doc = "Mandos plugin runner -- Run plugins" };
550
551
/* Parse using parse_opt_config_file() in order to get the custom
552
config file location, if any. */
553
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
554
if(ret == ARGP_ERR_UNKNOWN){
555
fprintf(stderr, "Unknown error while parsing arguments\n");
556
exitstatus = EXIT_FAILURE;
557
goto fallback;
558
}
559
560
/* Reset to the normal argument parser */
561
argp.parser = parse_opt;
562
563
/* Open the configfile if available */
564
if(argfile == NULL){
565
conffp = fopen(AFILE, "r");
566
} else {
567
conffp = fopen(argfile, "r");
568
}
569
if(conffp != NULL){
570
char *org_line = NULL;
571
char *p, *arg, *new_arg, *line;
572
size_t size = 0;
573
const char whitespace_delims[] = " \r\t\f\v\n";
574
const char comment_delim[] = "#";
575
576
custom_argc = 1;
577
custom_argv = malloc(sizeof(char*) * 2);
578
if(custom_argv == NULL){
579
perror("malloc");
580
exitstatus = EXIT_FAILURE;
581
goto fallback;
582
}
583
custom_argv[0] = argv[0];
584
custom_argv[1] = NULL;
585
586
/* for each line in the config file, strip whitespace and ignore
587
commented text */
588
while(true){
589
sret = getline(&org_line, &size, conffp);
590
if(sret == -1){
591
break;
592
}
593
594
line = org_line;
595
arg = strsep(&line, comment_delim);
596
while((p = strsep(&arg, whitespace_delims)) != NULL){
597
if(p[0] == '\0'){
598
continue;
599
}
600
new_arg = strdup(p);
601
if(new_arg == NULL){
602
perror("strdup");
603
exitstatus = EXIT_FAILURE;
604
free(org_line);
605
goto fallback;
606
}
607
608
custom_argc += 1;
609
custom_argv = realloc(custom_argv, sizeof(char *)
610
* ((unsigned int) custom_argc + 1));
611
if(custom_argv == NULL){
612
perror("realloc");
613
exitstatus = EXIT_FAILURE;
614
free(org_line);
615
goto fallback;
616
}
617
custom_argv[custom_argc-1] = new_arg;
618
custom_argv[custom_argc] = NULL;
619
}
620
}
621
free(org_line);
622
} else {
623
/* Check for harmful errors and go to fallback. Other errors might
624
not affect opening plugins */
625
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
626
perror("fopen");
627
exitstatus = EXIT_FAILURE;
628
goto fallback;
629
}
630
}
631
/* If there was any arguments from configuration file,
632
pass them to parser as command arguments */
633
if(custom_argv != NULL){
634
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
635
0, NULL);
636
if(ret == ARGP_ERR_UNKNOWN){
637
fprintf(stderr, "Unknown error while parsing arguments\n");
638
exitstatus = EXIT_FAILURE;
639
goto fallback;
640
}
641
}
642
643
/* Parse actual command line arguments, to let them override the
644
config file */
645
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
646
if(ret == ARGP_ERR_UNKNOWN){
647
fprintf(stderr, "Unknown error while parsing arguments\n");
648
exitstatus = EXIT_FAILURE;
649
goto fallback;
650
}
651
652
if(debug){
653
for(plugin *p = plugin_list; p != NULL; p=p->next){
654
fprintf(stderr, "Plugin: %s has %d arguments\n",
655
p->name ? p->name : "Global", p->argc - 1);
656
for(char **a = p->argv; *a != NULL; a++){
657
fprintf(stderr, "\tArg: %s\n", *a);
658
}
659
fprintf(stderr, "...and %d environment variables\n", p->envc);
660
for(char **a = p->environ; *a != NULL; a++){
661
fprintf(stderr, "\t%s\n", *a);
662
}
663
}
664
}
665
666
/* Strip permissions down to nobody */
667
setgid(gid);
668
if(ret == -1){
669
perror("setgid");
670
}
671
ret = setuid(uid);
672
if(ret == -1){
673
perror("setuid");
674
}
675
676
if(plugindir == NULL){
677
dir = opendir(PDIR);
678
} else {
679
dir = opendir(plugindir);
680
}
681
68
682
if(dir == NULL){
69
fprintf(stderr, "Can not open directory\n");
70
return EXIT_FAILURE;
71
}
72
73
FD_ZERO(&rfds_orig);
74
683
perror("Could not open plugin dir");
684
exitstatus = EXIT_FAILURE;
685
goto fallback;
686
}
687
688
/* Set the FD_CLOEXEC flag on the directory, if possible */
689
{
690
int dir_fd = dirfd(dir);
691
if(dir_fd >= 0){
692
ret = set_cloexec_flag(dir_fd);
693
if(ret < 0){
694
perror("set_cloexec_flag");
695
exitstatus = EXIT_FAILURE;
696
goto fallback;
697
}
698
}
699
}
700
701
FD_ZERO(&rfds_all);
702
703
/* Read and execute any executable in the plugin directory*/
75
704
while(true){
76
705
dirst = readdir(dir);
77
706
78
// All directory entries have been processed
707
/* All directory entries have been processed */
79
708
if(dirst == NULL){
709
if(errno == EBADF){
710
perror("readdir");
711
exitstatus = EXIT_FAILURE;
712
goto fallback;
713
}
80
714
break;
81
715
}
82
716
83
717
d_name_len = strlen(dirst->d_name);
84
718
85
// Ignore dotfiles and backup files
86
if (dirst->d_name[0] == '.'
87
or dirst->d_name[d_name_len - 1] == '~'){
88
continue;
89
}
90
91
char *filename = malloc(d_name_len + plugindir_len + 2);
92
strcpy(filename, plugindir);
93
strcat(filename, "/");
94
strcat(filename, dirst->d_name);
95
96
stat(filename, &st);
97
98
if (S_ISREG(st.st_mode) and (access(filename, X_OK) == 0)){
99
// Starting a new process to be watched
100
process *new_process = malloc(sizeof(process));
101
int pipefd[2];
102
pipe(pipefd);
103
new_process->pid = fork();
104
if(new_process->pid == 0){
105
/* this is the child process */
719
/* Ignore dotfiles, backup files and other junk */
720
{
721
bool bad_name = false;
722
723
const char const *bad_prefixes[] = { ".", "#", NULL };
724
725
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
726
".dpkg-old",
727
".dpkg-bak",
728
".dpkg-divert", NULL };
729
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
730
size_t pre_len = strlen(*pre);
731
if((d_name_len >= pre_len)
732
and strncmp((dirst->d_name), *pre, pre_len) == 0){
733
if(debug){
734
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
735
" with bad prefix %s\n", dirst->d_name, *pre);
736
}
737
bad_name = true;
738
break;
739
}
740
}
741
if(bad_name){
742
continue;
743
}
744
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
745
size_t suf_len = strlen(*suf);
746
if((d_name_len >= suf_len)
747
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
748
== 0)){
749
if(debug){
750
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
751
" with bad suffix %s\n", dirst->d_name, *suf);
752
}
753
bad_name = true;
754
break;
755
}
756
}
757
758
if(bad_name){
759
continue;
760
}
761
}
762
763
char *filename;
764
if(plugindir == NULL){
765
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
766
} else {
767
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
768
}
769
if(ret < 0){
770
perror("asprintf");
771
continue;
772
}
773
774
ret = stat(filename, &st);
775
if(ret == -1){
776
perror("stat");
777
free(filename);
778
continue;
779
}
780
781
/* Ignore non-executable files */
782
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
783
if(debug){
784
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
785
" with bad type or mode\n", filename);
786
}
787
free(filename);
788
continue;
789
}
790
791
plugin *p = getplugin(dirst->d_name);
792
if(p == NULL){
793
perror("getplugin");
794
free(filename);
795
continue;
796
}
797
if(p->disabled){
798
if(debug){
799
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
800
dirst->d_name);
801
}
802
free(filename);
803
continue;
804
}
805
{
806
/* Add global arguments to argument list for this plugin */
807
plugin *g = getplugin(NULL);
808
if(g != NULL){
809
for(char **a = g->argv + 1; *a != NULL; a++){
810
if(not add_argument(p, *a)){
811
perror("add_argument");
812
}
813
}
814
/* Add global environment variables */
815
for(char **e = g->environ; *e != NULL; e++){
816
if(not add_environment(p, *e, false)){
817
perror("add_environment");
818
}
819
}
820
}
821
}
822
/* If this plugin has any environment variables, we will call
823
using execve and need to duplicate the environment from this
824
process, too. */
825
if(p->environ[0] != NULL){
826
for(char **e = environ; *e != NULL; e++){
827
if(not add_environment(p, *e, false)){
828
perror("add_environment");
829
}
830
}
831
}
832
833
int pipefd[2];
834
ret = pipe(pipefd);
835
if(ret == -1){
836
perror("pipe");
837
exitstatus = EXIT_FAILURE;
838
goto fallback;
839
}
840
/* Ask OS to automatic close the pipe on exec */
841
ret = set_cloexec_flag(pipefd[0]);
842
if(ret < 0){
843
perror("set_cloexec_flag");
844
exitstatus = EXIT_FAILURE;
845
goto fallback;
846
}
847
ret = set_cloexec_flag(pipefd[1]);
848
if(ret < 0){
849
perror("set_cloexec_flag");
850
exitstatus = EXIT_FAILURE;
851
goto fallback;
852
}
853
/* Block SIGCHLD until process is safely in process list */
854
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
855
if(ret < 0){
856
perror("sigprocmask");
857
exitstatus = EXIT_FAILURE;
858
goto fallback;
859
}
860
/* Starting a new process to be watched */
861
pid_t pid = fork();
862
if(pid == -1){
863
perror("fork");
864
exitstatus = EXIT_FAILURE;
865
goto fallback;
866
}
867
if(pid == 0){
868
/* this is the child process */
869
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
870
if(ret < 0){
871
perror("sigaction");
872
_exit(EXIT_FAILURE);
873
}
874
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
875
if(ret < 0){
876
perror("sigprocmask");
877
_exit(EXIT_FAILURE);
878
}
879
880
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
881
if(ret == -1){
882
perror("dup2");
883
_exit(EXIT_FAILURE);
884
}
885
886
if(dirfd(dir) < 0){
887
/* If dir has no file descriptor, we could not set FD_CLOEXEC
888
above and must now close it manually here. */
106
889
closedir(dir);
107
close(pipefd[0]); /* close unused read end of pipe */
108
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
109
/* create a new modified argument list */
110
char **new_argv = malloc(sizeof(char *)
111
* ((unsigned int) argc + 1));
112
new_argv[0] = filename;
113
for(int i = 1; i < argc; i++){
114
new_argv[i] = argv[i];
115
}
116
new_argv[argc] = NULL;
117
if(execv(filename, new_argv) < 0){
118
perror(argv[0]);
119
close(pipefd[1]);
120
exit(EXIT_FAILURE);
121
}
122
/* no return */
123
}
124
close(pipefd[1]); /* close unused write end of pipe */
125
new_process->fd = pipefd[0];
126
new_process->buffer = malloc(BUFFER_SIZE);
127
if (new_process->buffer == NULL){
128
perror(argv[0]);
129
goto end;
130
}
131
new_process->buffer_size = BUFFER_SIZE;
132
new_process->buffer_length = 0;
133
FD_SET(new_process->fd, &rfds_orig);
134
135
if (maxfd < new_process->fd){
136
maxfd = new_process->fd;
137
}
138
139
//List handling
140
new_process->next = process_list;
141
process_list = new_process;
890
}
891
if(p->environ[0] == NULL){
892
if(execv(filename, p->argv) < 0){
893
perror("execv");
894
_exit(EXIT_FAILURE);
895
}
896
} else {
897
if(execve(filename, p->argv, p->environ) < 0){
898
perror("execve");
899
_exit(EXIT_FAILURE);
900
}
901
}
902
/* no return */
903
}
904
/* Parent process */
905
close(pipefd[1]); /* Close unused write end of pipe */
906
free(filename);
907
plugin *new_plugin = getplugin(dirst->d_name);
908
if(new_plugin == NULL){
909
perror("getplugin");
910
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
911
if(ret < 0){
912
perror("sigprocmask");
913
}
914
exitstatus = EXIT_FAILURE;
915
goto fallback;
916
}
917
918
new_plugin->pid = pid;
919
new_plugin->fd = pipefd[0];
920
921
/* Unblock SIGCHLD so signal handler can be run if this process
922
has already completed */
923
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
924
if(ret < 0){
925
perror("sigprocmask");
926
exitstatus = EXIT_FAILURE;
927
goto fallback;
928
}
929
930
FD_SET(new_plugin->fd, &rfds_all);
931
932
if(maxfd < new_plugin->fd){
933
maxfd = new_plugin->fd;
142
934
}
143
935
}
144
936
145
937
closedir(dir);
146
147
if (process_list != NULL){
148
while(true){
149
fd_set rfds = rfds_orig;
150
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
151
if (select_ret == -1){
152
perror(argv[0]);
153
goto end;
154
}else{
155
for(process *process_itr = process_list; process_itr != NULL;
156
process_itr = process_itr->next){
157
if(FD_ISSET(process_itr->fd, &rfds)){
158
if(process_itr->buffer_length + BUFFER_SIZE
159
> process_itr->buffer_size){
160
process_itr->buffer = realloc(process_itr->buffer,
161
process_itr->buffer_size
162
+ (size_t) BUFFER_SIZE);
163
if (process_itr->buffer == NULL){
164
perror(argv[0]);
165
goto end;
166
}
167
process_itr->buffer_size += BUFFER_SIZE;
168
}
169
ret = read(process_itr->fd, process_itr->buffer
170
+ process_itr->buffer_length, BUFFER_SIZE);
171
if(ret < 0){
172
/* Read error from this process; ignore it */
173
continue;
174
}
175
process_itr->buffer_length += (size_t) ret;
176
if(ret == 0){
177
/* got EOF */
178
/* wait for process exit */
179
int status;
180
waitpid(process_itr->pid, &status, 0);
181
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
182
write(STDOUT_FILENO, process_itr->buffer,
183
process_itr->buffer_length);
184
goto end;
185
} else {
186
FD_CLR(process_itr->fd, &rfds_orig);
187
}
188
}
189
}
190
}
191
}
192
}
193
}
194
195
end:
196
for(process *process_itr = process_list; process_itr != NULL;
197
process_itr = process_itr->next){
198
close(process_itr->fd);
199
kill(process_itr->pid, SIGTERM);
200
free(process_itr->buffer);
201
}
202
203
while(true){
204
int status;
205
ret = wait(&status);
206
if (ret == -1){
207
if(errno != ECHILD){
208
perror("wait");
209
}
938
dir = NULL;
939
940
for(plugin *p = plugin_list; p != NULL; p = p->next){
941
if(p->pid != 0){
210
942
break;
211
943
}
212
}
213
return EXIT_SUCCESS;
944
if(p->next == NULL){
945
fprintf(stderr, "No plugin processes started. Incorrect plugin"
946
" directory?\n");
947
free_plugin_list();
948
}
949
}
950
951
/* Main loop while running plugins exist */
952
while(plugin_list){
953
fd_set rfds = rfds_all;
954
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
955
if(select_ret == -1){
956
perror("select");
957
exitstatus = EXIT_FAILURE;
958
goto fallback;
959
}
960
/* OK, now either a process completed, or something can be read
961
from one of them */
962
for(plugin *proc = plugin_list; proc != NULL;){
963
/* Is this process completely done? */
964
if(proc->completed and proc->eof){
965
/* Only accept the plugin output if it exited cleanly */
966
if(not WIFEXITED(proc->status)
967
or WEXITSTATUS(proc->status) != 0){
968
/* Bad exit by plugin */
969
970
if(debug){
971
if(WIFEXITED(proc->status)){
972
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
973
" status %d\n", proc->name,
974
(intmax_t) (proc->pid),
975
WEXITSTATUS(proc->status));
976
} else if(WIFSIGNALED(proc->status)){
977
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
978
" signal %d\n", proc->name,
979
(intmax_t) (proc->pid),
980
WTERMSIG(proc->status));
981
} else if(WCOREDUMP(proc->status)){
982
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
983
" core\n", proc->name, (intmax_t) (proc->pid));
984
}
985
}
986
987
/* Remove the plugin */
988
FD_CLR(proc->fd, &rfds_all);
989
990
/* Block signal while modifying process_list */
991
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
992
if(ret < 0){
993
perror("sigprocmask");
994
exitstatus = EXIT_FAILURE;
995
goto fallback;
996
}
997
998
plugin *next_plugin = proc->next;
999
free_plugin(proc);
1000
proc = next_plugin;
1001
1002
/* We are done modifying process list, so unblock signal */
1003
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1004
NULL);
1005
if(ret < 0){
1006
perror("sigprocmask");
1007
exitstatus = EXIT_FAILURE;
1008
goto fallback;
1009
}
1010
1011
if(plugin_list == NULL){
1012
break;
1013
}
1014
1015
continue;
1016
}
1017
1018
/* This process exited nicely, so print its buffer */
1019
1020
bool bret = print_out_password(proc->buffer,
1021
proc->buffer_length);
1022
if(not bret){
1023
perror("print_out_password");
1024
exitstatus = EXIT_FAILURE;
1025
}
1026
goto fallback;
1027
}
1028
1029
/* This process has not completed. Does it have any output? */
1030
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1031
/* This process had nothing to say at this time */
1032
proc = proc->next;
1033
continue;
1034
}
1035
/* Before reading, make the process' data buffer large enough */
1036
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1037
proc->buffer = realloc(proc->buffer, proc->buffer_size
1038
+ (size_t) BUFFER_SIZE);
1039
if(proc->buffer == NULL){
1040
perror("malloc");
1041
exitstatus = EXIT_FAILURE;
1042
goto fallback;
1043
}
1044
proc->buffer_size += BUFFER_SIZE;
1045
}
1046
/* Read from the process */
1047
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1048
BUFFER_SIZE);
1049
if(sret < 0){
1050
/* Read error from this process; ignore the error */
1051
proc = proc->next;
1052
continue;
1053
}
1054
if(sret == 0){
1055
/* got EOF */
1056
proc->eof = true;
1057
} else {
1058
proc->buffer_length += (size_t) sret;
1059
}
1060
}
1061
}
1062
1063
1064
fallback:
1065
1066
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1067
/* Fallback if all plugins failed, none are found or an error
1068
occured */
1069
bool bret;
1070
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1071
char *passwordbuffer = getpass("Password: ");
1072
size_t len = strlen(passwordbuffer);
1073
/* Strip trailing newline */
1074
if(len > 0 and passwordbuffer[len-1] == '\n'){
1075
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1076
len--;
1077
}
1078
bret = print_out_password(passwordbuffer, len);
1079
if(not bret){
1080
perror("print_out_password");
1081
exitstatus = EXIT_FAILURE;
1082
}
1083
}
1084
1085
/* Restore old signal handler */
1086
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1087
if(ret == -1){
1088
perror("sigaction");
1089
exitstatus = EXIT_FAILURE;
1090
}
1091
1092
if(custom_argv != NULL){
1093
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1094
free(*arg);
1095
}
1096
free(custom_argv);
1097
}
1098
1099
if(dir != NULL){
1100
closedir(dir);
1101
}
1102
1103
/* Kill the processes */
1104
for(plugin *p = plugin_list; p != NULL; p = p->next){
1105
if(p->pid != 0){
1106
close(p->fd);
1107
ret = kill(p->pid, SIGTERM);
1108
if(ret == -1 and errno != ESRCH){
1109
/* Set-uid proccesses might not get closed */
1110
perror("kill");
1111
}
1112
}
1113
}
1114
1115
/* Wait for any remaining child processes to terminate */
1116
do{
1117
ret = wait(NULL);
1118
} while(ret >= 0);
1119
if(errno != ECHILD){
1120
perror("wait");
1121
}
1122
1123
free_plugin_list();
1124
1125
free(plugindir);
1126
free(argfile);
1127
1128
return exitstatus;
214
1129
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0