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- Committer: Björn Påhlsson
- Date: 2007-10-28 17:59:38 UTC
- Revision ID: belorn@tower-20071028175938-26b85eaa85b84771
Working client and server and password system
- files added:
- bad-ca.pem
- files removed:
- .bzr-builddeb
- debian
- debian/po
- debian/source
- debian/tests
- debian/upstream
- dracut-module
- network-hooks.d
- plugin-helpers
- plugins.d
- files modified:
- Makefile
added
removed
plugin-runner.c
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2008-2022 Teddy Hogeborn
6
* Copyright © 2008-2022 Björn Påhlsson
7
*
8
* This file is part of Mandos.
9
*
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
14
*
15
* Mandos is distributed in the hope that it will be useful, but
16
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
* General Public License for more details.
19
*
20
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
22
*
23
* Contact the authors at <mandos@recompile.se>.
24
*/
25
26
#define _GNU_SOURCE /* strchrnul(), TEMP_FAILURE_RETRY(),
27
getline(), asprintf(), O_CLOEXEC,
28
scandirat(), pipe2() */
29
#include <argp.h> /* argp_program_version,
30
argp_program_bug_address,
31
struct argp_option,
32
struct argp_state, argp_error(),
33
ARGP_NO_EXIT, argp_state_help,
34
ARGP_HELP_STD_HELP,
35
ARGP_HELP_USAGE, ARGP_HELP_EXIT_OK,
36
ARGP_KEY_ARG, ARGP_ERR_UNKNOWN,
37
struct argp, argp_parse(),
38
ARGP_IN_ORDER, ARGP_NO_HELP */
39
#include <stdbool.h> /* bool, false, true */
40
#include <sys/types.h> /* pid_t, sig_atomic_t, uid_t, gid_t,
41
getuid(), setgid(), setuid() */
42
#include <stddef.h> /* size_t, NULL */
43
#include <iso646.h> /* or, and, not */
44
#include <string.h> /* strcmp(), strdup(), strchrnul(),
45
strncmp(), strlen(), strcpy(),
46
strsep(), strchr(), strsignal() */
47
#include <stdlib.h> /* malloc(), free(), reallocarray(),
48
realloc(), EXIT_SUCCESS */
49
#include <errno.h> /* errno, EINTR, ENOMEM, ECHILD,
50
error_t, EINVAL, EMFILE, ENFILE,
51
ENOENT, ESRCH */
52
#include <stdint.h> /* SIZE_MAX */
53
#define _GNU_SOURCE /* strchrnul(), TEMP_FAILURE_RETRY(),
54
getline(), asprintf(), O_CLOEXEC,
55
scandirat(), pipe2() */
56
#include <unistd.h> /* TEMP_FAILURE_RETRY(), ssize_t,
57
write(), STDOUT_FILENO, uid_t,
58
gid_t, getuid(), fchown(), close(),
59
symlink(), setgid(), setuid(),
60
faccessat(), X_OK, pipe(), pipe2(),
61
fork(), _exit(), dup2(), fexecve(),
62
read(), getpass() */
63
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
64
FD_CLOEXEC, open(), O_RDONLY,
65
O_CLOEXEC, openat() */
66
#include <sys/wait.h> /* waitpid(), WNOHANG, WIFEXITED(),
67
WEXITSTATUS(), WIFSIGNALED(),
68
WTERMSIG(), wait() */
69
#include <error.h> /* error() */
70
#include <stdio.h> /* FILE, fprintf(), fopen(),
71
getline(), fclose(), EOF,
72
asprintf(), stderr */
73
#include <dirent.h> /* struct dirent, scandirat(),
74
alphasort() */
75
#include <sys/stat.h> /* struct stat, fstat(), S_ISDIR(),
76
lstat(), S_ISREG() */
77
#include <sys/select.h> /* fd_set, FD_ZERO(), FD_SETSIZE,
78
FD_SET(), select(), FD_CLR(),
79
FD_ISSET() */
80
#include <signal.h> /* struct sigaction, SA_NOCLDSTOP,
81
sigemptyset(), sigaddset(),
82
SIGCHLD, sigprocmask(), SIG_BLOCK,
83
SIG_UNBLOCK, kill(), SIGTERM */
84
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
85
EX_CONFIG, EX_UNAVAILABLE, EX_OK */
86
#include <inttypes.h> /* intmax_t, strtoimax(), PRIdMAX */
87
#include <fnmatch.h> /* fnmatch(), FNM_FILE_NAME,
88
FNM_PERIOD, FNM_NOMATCH */
89
90
#define BUFFER_SIZE 256
91
92
#define PDIR "/lib/mandos/plugins.d"
93
#define PHDIR "/lib/mandos/plugin-helpers"
94
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
95
96
const char *argp_program_version = "plugin-runner " VERSION;
97
const char *argp_program_bug_address = "<mandos@recompile.se>";
98
99
typedef struct plugin{
100
char *name; /* can be NULL or any plugin name */
101
char **argv;
102
int argc;
103
char **environ;
104
int envc;
105
bool disabled;
106
107
/* Variables used for running processes*/
108
pid_t pid;
109
int fd;
110
char *buffer;
111
size_t buffer_size;
112
size_t buffer_length;
113
bool eof;
114
volatile sig_atomic_t completed;
115
int status;
116
struct plugin *next;
117
} plugin;
118
119
static plugin *plugin_list = NULL;
120
121
/* Gets an existing plugin based on name,
122
or if none is found, creates a new one */
123
__attribute__((warn_unused_result))
124
static plugin *getplugin(char *name){
125
/* Check for existing plugin with that name */
126
for(plugin *p = plugin_list; p != NULL; p = p->next){
127
if((p->name == name)
128
or (p->name and name and (strcmp(p->name, name) == 0))){
129
return p;
130
}
131
}
132
/* Create a new plugin */
133
plugin *new_plugin = NULL;
134
do {
135
new_plugin = malloc(sizeof(plugin));
136
} while(new_plugin == NULL and errno == EINTR);
137
if(new_plugin == NULL){
138
return NULL;
139
}
140
char *copy_name = NULL;
141
if(name != NULL){
142
do {
143
copy_name = strdup(name);
144
} while(copy_name == NULL and errno == EINTR);
145
if(copy_name == NULL){
146
int e = errno;
147
free(new_plugin);
148
errno = e;
149
return NULL;
150
}
151
}
152
153
*new_plugin = (plugin){ .name = copy_name,
154
.argc = 1,
155
.disabled = false,
156
.next = plugin_list };
157
158
do {
159
new_plugin->argv = malloc(sizeof(char *) * 2);
160
} while(new_plugin->argv == NULL and errno == EINTR);
161
if(new_plugin->argv == NULL){
162
int e = errno;
163
free(copy_name);
164
free(new_plugin);
165
errno = e;
166
return NULL;
167
}
168
new_plugin->argv[0] = copy_name;
169
new_plugin->argv[1] = NULL;
170
171
do {
172
new_plugin->environ = malloc(sizeof(char *));
173
} while(new_plugin->environ == NULL and errno == EINTR);
174
if(new_plugin->environ == NULL){
175
int e = errno;
176
free(copy_name);
177
free(new_plugin->argv);
178
free(new_plugin);
179
errno = e;
180
return NULL;
181
}
182
new_plugin->environ[0] = NULL;
183
184
/* Append the new plugin to the list */
185
plugin_list = new_plugin;
186
return new_plugin;
187
}
188
189
/* Helper function for add_argument and add_environment */
190
__attribute__((nonnull, warn_unused_result))
191
static bool add_to_char_array(const char *new, char ***array,
192
int *len){
193
/* Resize the pointed-to array to hold one more pointer */
194
char **new_array = NULL;
195
do {
196
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
197
new_array = reallocarray(*array, (size_t)((*len) + 2),
198
sizeof(char *));
199
#else
200
if(((size_t)((*len) + 2)) > (SIZE_MAX / sizeof(char *))){
201
/* overflow */
202
new_array = NULL;
203
errno = ENOMEM;
204
} else {
205
new_array = realloc(*array, (size_t)((*len) + 2)
206
* sizeof(char *));
207
}
208
#endif
209
} while(new_array == NULL and errno == EINTR);
210
/* Malloc check */
211
if(new_array == NULL){
212
return false;
213
}
214
*array = new_array;
215
/* Make a copy of the new string */
216
char *copy;
217
do {
218
copy = strdup(new);
219
} while(copy == NULL and errno == EINTR);
220
if(copy == NULL){
221
return false;
222
}
223
/* Insert the copy */
224
(*array)[*len] = copy;
225
(*len)++;
226
/* Add a new terminating NULL pointer to the last element */
227
(*array)[*len] = NULL;
228
return true;
229
}
230
231
/* Add to a plugin's argument vector */
232
__attribute__((nonnull(2), warn_unused_result))
233
static bool add_argument(plugin *p, const char *arg){
234
if(p == NULL){
235
return false;
236
}
237
return add_to_char_array(arg, &(p->argv), &(p->argc));
238
}
239
240
/* Add to a plugin's environment */
241
__attribute__((nonnull(2), warn_unused_result))
242
static bool add_environment(plugin *p, const char *def, bool replace){
243
if(p == NULL){
244
return false;
245
}
246
/* namelen = length of name of environment variable */
247
size_t namelen = (size_t)(strchrnul(def, '=') - def);
248
/* Search for this environment variable */
249
for(char **envdef = p->environ; *envdef != NULL; envdef++){
250
if(strncmp(*envdef, def, namelen + 1) == 0){
251
/* It already exists */
252
if(replace){
253
char *new_envdef;
254
do {
255
new_envdef = realloc(*envdef, strlen(def) + 1);
256
} while(new_envdef == NULL and errno == EINTR);
257
if(new_envdef == NULL){
258
return false;
259
}
260
*envdef = new_envdef;
261
strcpy(*envdef, def);
262
}
263
return true;
264
}
265
}
266
return add_to_char_array(def, &(p->environ), &(p->envc));
267
}
268
269
#ifndef O_CLOEXEC
270
/*
271
* Based on the example in the GNU LibC manual chapter 13.13 "File
272
* Descriptor Flags".
273
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
274
*/
275
__attribute__((warn_unused_result))
276
static int set_cloexec_flag(int fd){
277
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
278
/* If reading the flags failed, return error indication now. */
279
if(ret < 0){
280
return ret;
281
}
282
/* Store modified flag word in the descriptor. */
283
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
284
ret | FD_CLOEXEC));
285
}
286
#endif /* not O_CLOEXEC */
287
288
289
/* Mark processes as completed when they exit, and save their exit
290
status. */
291
static void handle_sigchld(__attribute__((unused)) int sig){
292
int old_errno = errno;
293
while(true){
294
plugin *proc = plugin_list;
295
int status;
296
pid_t pid = waitpid(-1, &status, WNOHANG);
297
if(pid == 0){
298
/* Only still running child processes */
299
break;
300
}
301
if(pid == -1){
302
if(errno == ECHILD){
303
/* No child processes */
304
break;
305
}
306
error(0, errno, "waitpid");
307
}
308
309
/* A child exited, find it in process_list */
310
while(proc != NULL and proc->pid != pid){
311
proc = proc->next;
312
}
313
if(proc == NULL){
314
/* Process not found in process list */
315
continue;
316
}
317
proc->status = status;
318
proc->completed = 1;
319
}
320
errno = old_errno;
321
}
322
323
/* Prints out a password to stdout */
324
__attribute__((nonnull, warn_unused_result))
325
static bool print_out_password(const char *buffer, size_t length){
326
ssize_t ret;
327
for(size_t written = 0; written < length; written += (size_t)ret){
328
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
329
length - written));
330
if(ret < 0){
331
return false;
332
}
333
}
334
return true;
335
}
336
337
/* Removes and free a plugin from the plugin list */
338
__attribute__((nonnull))
339
static void free_plugin(plugin *plugin_node){
340
341
for(char **arg = (plugin_node->argv)+1; *arg != NULL; arg++){
342
free(*arg);
343
}
344
free(plugin_node->name);
345
free(plugin_node->argv);
346
for(char **env = plugin_node->environ; *env != NULL; env++){
347
free(*env);
348
}
349
free(plugin_node->environ);
350
free(plugin_node->buffer);
351
352
/* Removes the plugin from the singly-linked list */
353
if(plugin_node == plugin_list){
354
/* First one - simple */
355
plugin_list = plugin_list->next;
356
} else {
357
/* Second one or later */
358
for(plugin *p = plugin_list; p != NULL; p = p->next){
359
if(p->next == plugin_node){
360
p->next = plugin_node->next;
361
break;
362
}
363
}
364
}
365
366
free(plugin_node);
367
}
368
369
static void free_plugin_list(void){
370
while(plugin_list != NULL){
371
free_plugin(plugin_list);
372
}
373
}
374
375
int main(int argc, char *argv[]){
376
char *plugindir = NULL;
377
char *pluginhelperdir = NULL;
378
char *argfile = NULL;
379
FILE *conffp;
380
struct dirent **direntries = NULL;
381
struct stat st;
382
fd_set rfds_all;
383
int ret, maxfd = 0;
384
ssize_t sret;
385
uid_t uid = 65534;
386
gid_t gid = 65534;
387
bool debug = false;
388
int exitstatus = EXIT_SUCCESS;
389
struct sigaction old_sigchld_action;
390
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
391
.sa_flags = SA_NOCLDSTOP };
392
char **custom_argv = NULL;
393
int custom_argc = 0;
394
int dir_fd = -1;
395
396
/* Establish a signal handler */
397
sigemptyset(&sigchld_action.sa_mask);
398
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
399
if(ret == -1){
400
error(0, errno, "sigaddset");
401
exitstatus = EX_OSERR;
402
goto fallback;
403
}
404
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
405
if(ret == -1){
406
error(0, errno, "sigaction");
407
exitstatus = EX_OSERR;
408
goto fallback;
409
}
410
411
/* The options we understand. */
412
struct argp_option options[] = {
413
{ .name = "global-options", .key = 'g',
414
.arg = "OPTION[,OPTION[,...]]",
415
.doc = "Options passed to all plugins" },
416
{ .name = "global-env", .key = 'G',
417
.arg = "VAR=value",
418
.doc = "Environment variable passed to all plugins" },
419
{ .name = "options-for", .key = 'o',
420
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
421
.doc = "Options passed only to specified plugin" },
422
{ .name = "env-for", .key = 'E',
423
.arg = "PLUGIN:ENV=value",
424
.doc = "Environment variable passed to specified plugin" },
425
{ .name = "disable", .key = 'd',
426
.arg = "PLUGIN",
427
.doc = "Disable a specific plugin", .group = 1 },
428
{ .name = "enable", .key = 'e',
429
.arg = "PLUGIN",
430
.doc = "Enable a specific plugin", .group = 1 },
431
{ .name = "plugin-dir", .key = 128,
432
.arg = "DIRECTORY",
433
.doc = "Specify a different plugin directory", .group = 2 },
434
{ .name = "config-file", .key = 129,
435
.arg = "FILE",
436
.doc = "Specify a different configuration file", .group = 2 },
437
{ .name = "userid", .key = 130,
438
.arg = "ID", .flags = 0,
439
.doc = "User ID the plugins will run as", .group = 3 },
440
{ .name = "groupid", .key = 131,
441
.arg = "ID", .flags = 0,
442
.doc = "Group ID the plugins will run as", .group = 3 },
443
{ .name = "debug", .key = 132,
444
.doc = "Debug mode", .group = 4 },
445
{ .name = "plugin-helper-dir", .key = 133,
446
.arg = "DIRECTORY",
447
.doc = "Specify a different plugin helper directory",
448
.group = 2 },
449
/*
450
* These reproduce what we would get without ARGP_NO_HELP
451
*/
452
{ .name = "help", .key = '?',
453
.doc = "Give this help list", .group = -1 },
454
{ .name = "usage", .key = -3,
455
.doc = "Give a short usage message", .group = -1 },
456
{ .name = "version", .key = 'V',
457
.doc = "Print program version", .group = -1 },
458
{ .name = NULL }
459
};
460
461
__attribute__((nonnull(3)))
462
error_t parse_opt(int key, char *arg, struct argp_state *state){
463
errno = 0;
464
switch(key){
465
char *tmp;
466
intmax_t tmp_id;
467
case 'g': /* --global-options */
468
{
469
char *plugin_option;
470
while((plugin_option = strsep(&arg, ",")) != NULL){
471
if(not add_argument(getplugin(NULL), plugin_option)){
472
break;
473
}
474
}
475
errno = 0;
476
}
477
break;
478
case 'G': /* --global-env */
479
if(add_environment(getplugin(NULL), arg, true)){
480
errno = 0;
481
}
482
break;
483
case 'o': /* --options-for */
484
{
485
char *option_list = strchr(arg, ':');
486
if(option_list == NULL){
487
argp_error(state, "No colon in \"%s\"", arg);
488
errno = EINVAL;
489
break;
490
}
491
*option_list = '\0';
492
option_list++;
493
if(arg[0] == '\0'){
494
argp_error(state, "Empty plugin name");
495
errno = EINVAL;
496
break;
497
}
498
char *option;
499
while((option = strsep(&option_list, ",")) != NULL){
500
if(not add_argument(getplugin(arg), option)){
501
break;
502
}
503
}
504
errno = 0;
505
}
506
break;
507
case 'E': /* --env-for */
508
{
509
char *envdef = strchr(arg, ':');
510
if(envdef == NULL){
511
argp_error(state, "No colon in \"%s\"", arg);
512
errno = EINVAL;
513
break;
514
}
515
*envdef = '\0';
516
envdef++;
517
if(arg[0] == '\0'){
518
argp_error(state, "Empty plugin name");
519
errno = EINVAL;
520
break;
521
}
522
if(add_environment(getplugin(arg), envdef, true)){
523
errno = 0;
524
}
525
}
526
break;
527
case 'd': /* --disable */
528
{
529
plugin *p = getplugin(arg);
530
if(p != NULL){
531
p->disabled = true;
532
errno = 0;
533
}
534
}
535
break;
536
case 'e': /* --enable */
537
{
538
plugin *p = getplugin(arg);
539
if(p != NULL){
540
p->disabled = false;
541
errno = 0;
542
}
543
}
544
break;
545
case 128: /* --plugin-dir */
546
free(plugindir);
547
plugindir = strdup(arg);
548
if(plugindir != NULL){
549
errno = 0;
550
}
551
break;
552
case 129: /* --config-file */
553
/* This is already done by parse_opt_config_file() */
554
break;
555
case 130: /* --userid */
556
tmp_id = strtoimax(arg, &tmp, 10);
557
if(errno != 0 or tmp == arg or *tmp != '\0'
558
or tmp_id != (uid_t)tmp_id){
559
argp_error(state, "Bad user ID number: \"%s\", using %"
560
PRIdMAX, arg, (intmax_t)uid);
561
break;
562
}
563
uid = (uid_t)tmp_id;
564
errno = 0;
565
break;
566
case 131: /* --groupid */
567
tmp_id = strtoimax(arg, &tmp, 10);
568
if(errno != 0 or tmp == arg or *tmp != '\0'
569
or tmp_id != (gid_t)tmp_id){
570
argp_error(state, "Bad group ID number: \"%s\", using %"
571
PRIdMAX, arg, (intmax_t)gid);
572
break;
573
}
574
gid = (gid_t)tmp_id;
575
errno = 0;
576
break;
577
case 132: /* --debug */
578
debug = true;
579
break;
580
case 133: /* --plugin-helper-dir */
581
free(pluginhelperdir);
582
pluginhelperdir = strdup(arg);
583
if(pluginhelperdir != NULL){
584
errno = 0;
585
}
586
break;
587
/*
588
* These reproduce what we would get without ARGP_NO_HELP
589
*/
590
case '?': /* --help */
591
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
592
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
593
__builtin_unreachable();
594
case -3: /* --usage */
595
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
596
argp_state_help(state, state->out_stream,
597
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
598
__builtin_unreachable();
599
case 'V': /* --version */
600
fprintf(state->out_stream, "%s\n", argp_program_version);
601
exit(EXIT_SUCCESS);
602
break;
603
/*
604
* When adding more options before this line, remember to also add a
605
* "case" to the "parse_opt_config_file" function below.
606
*/
607
case ARGP_KEY_ARG:
608
/* Cryptsetup always passes an argument, which is an empty
609
string if "none" was specified in /etc/crypttab. So if
610
argument was empty, we ignore it silently. */
611
if(arg[0] == '\0'){
612
break;
613
}
614
#if __GNUC__ >= 7
615
__attribute__((fallthrough));
616
#else
617
/* FALLTHROUGH */
618
#endif
619
default:
620
return ARGP_ERR_UNKNOWN;
621
}
622
return errno; /* Set to 0 at start */
623
}
624
625
/* This option parser is the same as parse_opt() above, except it
626
ignores everything but the --config-file option. */
627
error_t parse_opt_config_file(int key, char *arg,
628
__attribute__((unused))
629
struct argp_state *state){
630
errno = 0;
631
switch(key){
632
case 'g': /* --global-options */
633
case 'G': /* --global-env */
634
case 'o': /* --options-for */
635
case 'E': /* --env-for */
636
case 'd': /* --disable */
637
case 'e': /* --enable */
638
case 128: /* --plugin-dir */
639
break;
640
case 129: /* --config-file */
641
free(argfile);
642
argfile = strdup(arg);
643
if(argfile != NULL){
644
errno = 0;
645
}
646
break;
647
case 130: /* --userid */
648
case 131: /* --groupid */
649
case 132: /* --debug */
650
case 133: /* --plugin-helper-dir */
651
case '?': /* --help */
652
case -3: /* --usage */
653
case 'V': /* --version */
654
case ARGP_KEY_ARG:
655
break;
656
default:
657
return ARGP_ERR_UNKNOWN;
658
}
659
return errno;
660
}
661
662
struct argp argp = { .options = options,
663
.parser = parse_opt_config_file,
664
.args_doc = "",
665
.doc = "Mandos plugin runner -- Run plugins" };
666
667
/* Parse using parse_opt_config_file() in order to get the custom
668
config file location, if any. */
669
ret = argp_parse(&argp, argc, argv,
670
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
671
NULL, NULL);
672
switch(ret){
673
case 0:
674
break;
675
case ENOMEM:
676
default:
677
errno = ret;
678
error(0, errno, "argp_parse");
679
exitstatus = EX_OSERR;
680
goto fallback;
681
case EINVAL:
682
exitstatus = EX_USAGE;
683
goto fallback;
684
}
685
686
/* Reset to the normal argument parser */
687
argp.parser = parse_opt;
688
689
/* Open the configfile if available */
690
if(argfile == NULL){
691
conffp = fopen(AFILE, "r");
692
} else {
693
conffp = fopen(argfile, "r");
694
}
695
if(conffp != NULL){
696
char *org_line = NULL;
697
char *p, *arg, *new_arg, *line;
698
size_t size = 0;
699
const char whitespace_delims[] = " \r\t\f\v\n";
700
const char comment_delim[] = "#";
701
702
custom_argc = 1;
703
custom_argv = malloc(sizeof(char*) * 2);
704
if(custom_argv == NULL){
705
error(0, errno, "malloc");
706
exitstatus = EX_OSERR;
707
goto fallback;
708
}
709
custom_argv[0] = argv[0];
710
custom_argv[1] = NULL;
711
712
/* for each line in the config file, strip whitespace and ignore
713
commented text */
714
while(true){
715
sret = getline(&org_line, &size, conffp);
716
if(sret == -1){
717
break;
718
}
719
720
line = org_line;
721
arg = strsep(&line, comment_delim);
722
while((p = strsep(&arg, whitespace_delims)) != NULL){
723
if(p[0] == '\0'){
724
continue;
725
}
726
new_arg = strdup(p);
727
if(new_arg == NULL){
728
error(0, errno, "strdup");
729
exitstatus = EX_OSERR;
730
free(org_line);
731
goto fallback;
732
}
733
734
custom_argc += 1;
735
{
736
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
737
char **new_argv = reallocarray(custom_argv,
738
(size_t)custom_argc + 1,
739
sizeof(char *));
740
#else
741
char **new_argv = NULL;
742
if(((size_t)custom_argc + 1) > (SIZE_MAX / sizeof(char *))){
743
/* overflow */
744
errno = ENOMEM;
745
} else {
746
new_argv = realloc(custom_argv, ((size_t)custom_argc + 1)
747
* sizeof(char *));
748
}
749
#endif
750
if(new_argv == NULL){
751
error(0, errno, "reallocarray");
752
exitstatus = EX_OSERR;
753
free(new_arg);
754
free(org_line);
755
goto fallback;
756
} else {
757
custom_argv = new_argv;
758
}
759
}
760
custom_argv[custom_argc-1] = new_arg;
761
custom_argv[custom_argc] = NULL;
762
}
763
}
764
do {
765
ret = fclose(conffp);
766
} while(ret == EOF and errno == EINTR);
767
if(ret == EOF){
768
error(0, errno, "fclose");
769
exitstatus = EX_IOERR;
770
goto fallback;
771
}
772
free(org_line);
773
} else {
774
/* Check for harmful errors and go to fallback. Other errors might
775
not affect opening plugins */
776
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
777
error(0, errno, "fopen");
778
exitstatus = EX_OSERR;
779
goto fallback;
780
}
781
}
782
/* If there were any arguments from the configuration file, pass
783
them to parser as command line arguments */
784
if(custom_argv != NULL){
785
ret = argp_parse(&argp, custom_argc, custom_argv,
786
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
787
NULL, NULL);
788
switch(ret){
789
case 0:
790
break;
791
case ENOMEM:
792
default:
793
errno = ret;
794
error(0, errno, "argp_parse");
795
exitstatus = EX_OSERR;
796
goto fallback;
797
case EINVAL:
798
exitstatus = EX_CONFIG;
799
goto fallback;
800
}
801
}
802
803
/* Parse actual command line arguments, to let them override the
804
config file */
805
ret = argp_parse(&argp, argc, argv,
806
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
807
NULL, NULL);
808
switch(ret){
809
case 0:
810
break;
811
case ENOMEM:
812
default:
813
errno = ret;
814
error(0, errno, "argp_parse");
815
exitstatus = EX_OSERR;
816
goto fallback;
817
case EINVAL:
818
exitstatus = EX_USAGE;
819
goto fallback;
820
}
821
822
{
823
char *pluginhelperenv;
824
bool bret = true;
825
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
826
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
827
if(ret != -1){
828
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
829
}
830
if(ret == -1 or not bret){
831
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
832
" environment variable to \"%s\" for all plugins\n",
833
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
834
}
835
if(ret != -1){
836
free(pluginhelperenv);
837
}
838
}
839
840
if(debug){
841
for(plugin *p = plugin_list; p != NULL; p = p->next){
842
fprintf(stderr, "Plugin: %s has %d arguments\n",
843
p->name ? p->name : "Global", p->argc - 1);
844
for(char **a = p->argv; *a != NULL; a++){
845
fprintf(stderr, "\tArg: %s\n", *a);
846
}
847
fprintf(stderr, "...and %d environment variables\n", p->envc);
848
for(char **a = p->environ; *a != NULL; a++){
849
fprintf(stderr, "\t%s\n", *a);
850
}
851
}
852
}
853
854
if(getuid() == 0){
855
/* Work around Debian bug #633582:
856
<https://bugs.debian.org/633582> */
857
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
858
if(plugindir_fd == -1){
859
if(errno != ENOENT){
860
error(0, errno, "open(\"" PDIR "\")");
861
}
862
} else {
863
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
864
if(ret == -1){
865
error(0, errno, "fstat");
866
} else {
867
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
868
ret = fchown(plugindir_fd, uid, gid);
869
if(ret == -1){
870
error(0, errno, "fchown");
871
}
872
}
873
}
874
close(plugindir_fd);
875
}
876
877
/* Work around Debian bug #981302
878
<https://bugs.debian.org/981302> */
879
if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){
880
ret = symlink("/proc/self/fd", "/dev/fd");
881
if(ret == -1){
882
error(0, errno, "Failed to create /dev/fd symlink");
883
}
884
}
885
}
886
887
/* Lower permissions */
888
ret = setgid(gid);
889
if(ret == -1){
890
error(0, errno, "setgid");
891
}
892
ret = setuid(uid);
893
if(ret == -1){
894
error(0, errno, "setuid");
895
}
896
897
/* Open plugin directory with close_on_exec flag */
898
{
899
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
900
#ifdef O_CLOEXEC
901
O_CLOEXEC
902
#else /* not O_CLOEXEC */
903
0
904
#endif /* not O_CLOEXEC */
905
);
906
if(dir_fd == -1){
907
error(0, errno, "Could not open plugin dir");
908
exitstatus = EX_UNAVAILABLE;
909
goto fallback;
910
}
911
912
#ifndef O_CLOEXEC
913
/* Set the FD_CLOEXEC flag on the directory */
914
ret = set_cloexec_flag(dir_fd);
915
if(ret < 0){
916
error(0, errno, "set_cloexec_flag");
917
exitstatus = EX_OSERR;
918
goto fallback;
919
}
920
#endif /* O_CLOEXEC */
921
}
922
923
int good_name(const struct dirent * const dirent){
924
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
925
"*.dpkg-old", "*.dpkg-bak",
926
"*.dpkg-divert", NULL };
927
#ifdef __GNUC__
928
#pragma GCC diagnostic push
929
#pragma GCC diagnostic ignored "-Wcast-qual"
930
#endif
931
for(const char **pat = (const char **)patterns;
932
*pat != NULL; pat++){
933
#ifdef __GNUC__
934
#pragma GCC diagnostic pop
935
#endif
936
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
937
!= FNM_NOMATCH){
938
if(debug){
939
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
940
" matching pattern %s\n", dirent->d_name, *pat);
941
}
942
return 0;
943
}
944
}
945
return 1;
946
}
947
948
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
949
alphasort);
950
if(numplugins == -1){
951
error(0, errno, "Could not scan plugin dir");
952
direntries = NULL;
953
exitstatus = EX_OSERR;
954
goto fallback;
955
}
956
957
FD_ZERO(&rfds_all);
958
959
/* Read and execute any executable in the plugin directory*/
960
for(int i = 0; i < numplugins; i++){
961
962
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
963
if(plugin_fd == -1){
964
error(0, errno, "Could not open plugin");
965
free(direntries[i]);
966
continue;
967
}
968
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
969
if(ret == -1){
970
error(0, errno, "stat");
971
close(plugin_fd);
972
free(direntries[i]);
973
continue;
974
}
975
976
/* Ignore non-executable files */
977
if(not S_ISREG(st.st_mode)
978
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
979
X_OK, 0)) != 0)){
980
if(debug){
981
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
982
" with bad type or mode\n",
983
plugindir != NULL ? plugindir : PDIR,
984
direntries[i]->d_name);
985
}
986
close(plugin_fd);
987
free(direntries[i]);
988
continue;
989
}
990
991
plugin *p = getplugin(direntries[i]->d_name);
992
if(p == NULL){
993
error(0, errno, "getplugin");
994
close(plugin_fd);
995
free(direntries[i]);
996
continue;
997
}
998
if(p->disabled){
999
if(debug){
1000
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
1001
direntries[i]->d_name);
1002
}
1003
close(plugin_fd);
1004
free(direntries[i]);
1005
continue;
1006
}
1007
{
1008
/* Add global arguments to argument list for this plugin */
1009
plugin *g = getplugin(NULL);
1010
if(g != NULL){
1011
for(char **a = g->argv + 1; *a != NULL; a++){
1012
if(not add_argument(p, *a)){
1013
error(0, errno, "add_argument");
1014
}
1015
}
1016
/* Add global environment variables */
1017
for(char **e = g->environ; *e != NULL; e++){
1018
if(not add_environment(p, *e, false)){
1019
error(0, errno, "add_environment");
1020
}
1021
}
1022
}
1023
}
1024
/* If this plugin has any environment variables, we need to
1025
duplicate the environment from this process, too. */
1026
if(p->environ[0] != NULL){
1027
for(char **e = environ; *e != NULL; e++){
1028
if(not add_environment(p, *e, false)){
1029
error(0, errno, "add_environment");
1030
}
1031
}
1032
}
1033
1034
int pipefd[2];
1035
#ifndef O_CLOEXEC
1036
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1037
#else /* O_CLOEXEC */
1038
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
1039
#endif /* O_CLOEXEC */
1040
if(ret == -1){
1041
error(0, errno, "pipe");
1042
exitstatus = EX_OSERR;
1043
free(direntries[i]);
1044
goto fallback;
1045
}
1046
if(pipefd[0] >= FD_SETSIZE){
1047
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1048
FD_SETSIZE);
1049
close(pipefd[0]);
1050
close(pipefd[1]);
1051
exitstatus = EX_OSERR;
1052
free(direntries[i]);
1053
goto fallback;
1054
}
1055
#ifndef O_CLOEXEC
1056
/* Ask OS to automatic close the pipe on exec */
1057
ret = set_cloexec_flag(pipefd[0]);
1058
if(ret < 0){
1059
error(0, errno, "set_cloexec_flag");
1060
close(pipefd[0]);
1061
close(pipefd[1]);
1062
exitstatus = EX_OSERR;
1063
free(direntries[i]);
1064
goto fallback;
1065
}
1066
ret = set_cloexec_flag(pipefd[1]);
1067
if(ret < 0){
1068
error(0, errno, "set_cloexec_flag");
1069
close(pipefd[0]);
1070
close(pipefd[1]);
1071
exitstatus = EX_OSERR;
1072
free(direntries[i]);
1073
goto fallback;
1074
}
1075
#endif /* not O_CLOEXEC */
1076
/* Block SIGCHLD until process is safely in process list */
1077
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1078
&sigchld_action.sa_mask,
1079
NULL));
1080
if(ret < 0){
1081
error(0, errno, "sigprocmask");
1082
exitstatus = EX_OSERR;
1083
free(direntries[i]);
1084
goto fallback;
1085
}
1086
/* Starting a new process to be watched */
1087
pid_t pid;
1088
do {
1089
pid = fork();
1090
} while(pid == -1 and errno == EINTR);
1091
if(pid == -1){
1092
error(0, errno, "fork");
1093
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1094
&sigchld_action.sa_mask, NULL));
1095
close(pipefd[0]);
1096
close(pipefd[1]);
1097
exitstatus = EX_OSERR;
1098
free(direntries[i]);
1099
goto fallback;
1100
}
1101
if(pid == 0){
1102
/* this is the child process */
1103
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1104
if(ret < 0){
1105
error(0, errno, "sigaction");
1106
_exit(EX_OSERR);
1107
}
1108
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1109
if(ret < 0){
1110
error(0, errno, "sigprocmask");
1111
_exit(EX_OSERR);
1112
}
1113
1114
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1115
if(ret == -1){
1116
error(0, errno, "dup2");
1117
_exit(EX_OSERR);
1118
}
1119
1120
if(fexecve(plugin_fd, p->argv,
1121
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1122
error(0, errno, "fexecve for %s/%s",
1123
plugindir != NULL ? plugindir : PDIR,
1124
direntries[i]->d_name);
1125
_exit(EX_OSERR);
1126
}
1127
/* no return */
1128
}
1129
/* Parent process */
1130
close(pipefd[1]); /* Close unused write end of pipe */
1131
close(plugin_fd);
1132
plugin *new_plugin = getplugin(direntries[i]->d_name);
1133
if(new_plugin == NULL){
1134
error(0, errno, "getplugin");
1135
ret = (int)(TEMP_FAILURE_RETRY
1136
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1137
NULL)));
1138
if(ret < 0){
1139
error(0, errno, "sigprocmask");
1140
}
1141
exitstatus = EX_OSERR;
1142
free(direntries[i]);
1143
goto fallback;
1144
}
1145
free(direntries[i]);
1146
1147
new_plugin->pid = pid;
1148
new_plugin->fd = pipefd[0];
1149
1150
if(debug){
1151
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1152
new_plugin->name, (intmax_t) (new_plugin->pid));
1153
}
1154
1155
/* Unblock SIGCHLD so signal handler can be run if this process
1156
has already completed */
1157
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1158
&sigchld_action.sa_mask,
1159
NULL));
1160
if(ret < 0){
1161
error(0, errno, "sigprocmask");
1162
exitstatus = EX_OSERR;
1163
goto fallback;
1164
}
1165
1166
FD_SET(new_plugin->fd, &rfds_all);
1167
1168
if(maxfd < new_plugin->fd){
1169
maxfd = new_plugin->fd;
1170
}
1171
}
1172
1173
free(direntries);
1174
direntries = NULL;
1175
close(dir_fd);
1176
dir_fd = -1;
1177
free_plugin(getplugin(NULL));
1178
1179
for(plugin *p = plugin_list; p != NULL; p = p->next){
1180
if(p->pid != 0){
1181
break;
1182
}
1183
if(p->next == NULL){
1184
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1185
" directory?\n");
1186
free_plugin_list();
1187
}
1188
}
1189
1190
/* Main loop while running plugins exist */
1191
while(plugin_list){
1192
fd_set rfds = rfds_all;
1193
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1194
if(select_ret == -1 and errno != EINTR){
1195
error(0, errno, "select");
1196
exitstatus = EX_OSERR;
1197
goto fallback;
1198
}
1199
/* OK, now either a process completed, or something can be read
1200
from one of them */
1201
for(plugin *proc = plugin_list; proc != NULL;){
1202
/* Is this process completely done? */
1203
if(proc->completed and proc->eof){
1204
/* Only accept the plugin output if it exited cleanly */
1205
if(not WIFEXITED(proc->status)
1206
or WEXITSTATUS(proc->status) != 0){
1207
/* Bad exit by plugin */
1208
1209
if(debug){
1210
if(WIFEXITED(proc->status)){
1211
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1212
" status %d\n", proc->name,
1213
(intmax_t) (proc->pid),
1214
WEXITSTATUS(proc->status));
1215
} else if(WIFSIGNALED(proc->status)){
1216
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1217
" signal %d: %s\n", proc->name,
1218
(intmax_t) (proc->pid),
1219
WTERMSIG(proc->status),
1220
strsignal(WTERMSIG(proc->status)));
1221
}
1222
}
1223
1224
/* Remove the plugin */
1225
FD_CLR(proc->fd, &rfds_all);
1226
1227
/* Block signal while modifying process_list */
1228
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1229
(SIG_BLOCK,
1230
&sigchld_action.sa_mask,
1231
NULL));
1232
if(ret < 0){
1233
error(0, errno, "sigprocmask");
1234
exitstatus = EX_OSERR;
1235
goto fallback;
1236
}
1237
1238
plugin *next_plugin = proc->next;
1239
free_plugin(proc);
1240
proc = next_plugin;
1241
1242
/* We are done modifying process list, so unblock signal */
1243
ret = (int)(TEMP_FAILURE_RETRY
1244
(sigprocmask(SIG_UNBLOCK,
1245
&sigchld_action.sa_mask, NULL)));
1246
if(ret < 0){
1247
error(0, errno, "sigprocmask");
1248
exitstatus = EX_OSERR;
1249
goto fallback;
1250
}
1251
1252
if(plugin_list == NULL){
1253
break;
1254
}
1255
1256
continue;
1257
}
1258
1259
/* This process exited nicely, so print its buffer */
1260
1261
bool bret = print_out_password(proc->buffer,
1262
proc->buffer_length);
1263
if(not bret){
1264
error(0, errno, "print_out_password");
1265
exitstatus = EX_IOERR;
1266
}
1267
goto fallback;
1268
}
1269
1270
/* This process has not completed. Does it have any output? */
1271
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1272
/* This process had nothing to say at this time */
1273
proc = proc->next;
1274
continue;
1275
}
1276
/* Before reading, make the process' data buffer large enough */
1277
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1278
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1279
+ (size_t) BUFFER_SIZE);
1280
if(new_buffer == NULL){
1281
error(0, errno, "malloc");
1282
exitstatus = EX_OSERR;
1283
goto fallback;
1284
}
1285
proc->buffer = new_buffer;
1286
proc->buffer_size += BUFFER_SIZE;
1287
}
1288
/* Read from the process */
1289
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1290
proc->buffer
1291
+ proc->buffer_length,
1292
BUFFER_SIZE));
1293
if(sret < 0){
1294
/* Read error from this process; ignore the error */
1295
proc = proc->next;
1296
continue;
1297
}
1298
if(sret == 0){
1299
/* got EOF */
1300
proc->eof = true;
1301
} else {
1302
proc->buffer_length += (size_t) sret;
1303
}
1304
}
1305
}
1306
1307
1308
fallback:
1309
1310
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1311
and exitstatus != EX_OK)){
1312
/* Fallback if all plugins failed, none are found or an error
1313
occured */
1314
bool bret;
1315
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1316
char *passwordbuffer = getpass("Password: ");
1317
size_t len = strlen(passwordbuffer);
1318
/* Strip trailing newline */
1319
if(len > 0 and passwordbuffer[len-1] == '\n'){
1320
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1321
len--;
1322
}
1323
bret = print_out_password(passwordbuffer, len);
1324
if(not bret){
1325
error(0, errno, "print_out_password");
1326
exitstatus = EX_IOERR;
1327
}
1328
}
1329
1330
/* Restore old signal handler */
1331
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1332
if(ret == -1){
1333
error(0, errno, "sigaction");
1334
exitstatus = EX_OSERR;
1335
}
1336
1337
if(custom_argv != NULL){
1338
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1339
free(*arg);
1340
}
1341
free(custom_argv);
1342
}
1343
1344
free(direntries);
1345
1346
if(dir_fd != -1){
1347
close(dir_fd);
1348
}
1349
1350
/* Kill the processes */
1351
for(plugin *p = plugin_list; p != NULL; p = p->next){
1352
if(p->pid != 0){
1353
close(p->fd);
1354
ret = kill(p->pid, SIGTERM);
1355
if(ret == -1 and errno != ESRCH){
1356
/* Set-uid proccesses might not get closed */
1357
error(0, errno, "kill");
1358
}
1359
}
1360
}
1361
1362
/* Wait for any remaining child processes to terminate */
1363
do {
1364
ret = wait(NULL);
1365
} while(ret >= 0);
1366
if(errno != ECHILD){
1367
error(0, errno, "wait");
1368
}
1369
1370
free_plugin_list();
1371
1372
free(plugindir);
1373
free(pluginhelperdir);
1374
free(argfile);
1375
1376
return exitstatus;
1377
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0