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- Committer: Teddy Hogeborn
- Date: 2008-09-01 16:19:32 UTC
- Revision ID: teddy@fukt.bsnet.se-20080901161932-ostp7tulh9aijulh
* plugin-runner.c (add_environment): Never insert existing environment
variables.
(main): Rename "--global-envs" to "--global-env" and "--envs-for" to
"--env-for".
* plugin-runner.xml (SYNOPSIS): Rename "--global-envs" to
"--global-env" and "--envs-for" to
"--env-for".
(OPTIONS): Added "--global-env" and "--env-for".
(FALLBACK): Add id attribute.
(EXIT STATUS): Add text.
(ENVIRONMENT): New section.
(FILES): Document configuration file.
variables.
(main): Rename "--global-envs" to "--global-env" and "--envs-for" to
"--env-for".
* plugin-runner.xml (SYNOPSIS): Rename "--global-envs" to
"--global-env" and "--envs-for" to
"--env-for".
(OPTIONS): Added "--global-env" and "--env-for".
(FALLBACK): Add id attribute.
(EXIT STATUS): Add text.
(ENVIRONMENT): New section.
(FILES): Document configuration file.
- files added:
- .bzrignore
- files removed:
- ca.pem
- files renamed:
- mandos-clients.conf => clients.conf
- server.py => mandos
- plugbasedclient.c => plugin-runner.c
- plugins.d/passprompt.c => plugins.d/password-prompt.c
- plugins.d/mandosclient.c => plugins.d/password-request.c
- files modified:
- Makefile
added
removed
plugin-runner.c
1
#include <stdio.h> /* popen, fileno */
2
#include <iso646.h> /* and, or, not */
3
#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
4
WIFEXITED, WEXITSTATUS, wait */
5
#include <sys/wait.h> /* wait */
6
#include <dirent.h> /* DIR, opendir */
7
#include <sys/stat.h> /* stat, struct stat */
8
#include <unistd.h> /* stat, struct stat, chdir */
9
#include <stdlib.h> /* EXIT_FAILURE */
10
#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET, FD_ISSET */
11
#include <string.h> /* strlen, strcpy, strcat */
12
#include <stdbool.h> /* true */
13
#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
14
#include <errno.h> /* errno */
15
16
struct process;
17
18
typedef struct process{
1
/* -*- coding: utf-8 -*- */
2
/*
3
* Mandos plugin runner - Run Mandos plugins
4
*
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
6
*
7
* This program is free software: you can redistribute it and/or
8
* modify it under the terms of the GNU General Public License as
9
* published by the Free Software Foundation, either version 3 of the
10
* License, or (at your option) any later version.
11
*
12
* This program is distributed in the hope that it will be useful, but
13
* WITHOUT ANY WARRANTY; without even the implied warranty of
14
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15
* General Public License for more details.
16
*
17
* You should have received a copy of the GNU General Public License
18
* along with this program. If not, see
19
* <http://www.gnu.org/licenses/>.
20
*
21
* Contact the authors at <mandos@fukt.bsnet.se>.
22
*/
23
24
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
25
asprintf() */
26
#include <stddef.h> /* size_t, NULL */
27
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
EXIT_SUCCESS, realloc() */
29
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
stat, waitpid(), WIFEXITED(),
34
WEXITSTATUS(), wait(), pid_t,
35
uid_t, gid_t, getuid(), getgid(),
36
dirfd() */
37
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
FD_SET(), FD_ISSET(), FD_CLR */
39
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
40
WEXITSTATUS() */
41
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
44
readdir(), closedir(), dirfd() */
45
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
46
fcntl(), setuid(), setgid(),
47
F_GETFD, F_SETFD, FD_CLOEXEC,
48
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
50
execv(), write(), read(),
51
close() */
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC */
54
#include <string.h> /* strsep, strlen(), asprintf() */
55
#include <errno.h> /* errno */
56
#include <argp.h> /* struct argp_option, struct
57
argp_state, struct argp,
58
argp_parse(), ARGP_ERR_UNKNOWN,
59
ARGP_KEY_END, ARGP_KEY_ARG,
60
error_t */
61
#include <signal.h> /* struct sigaction, sigemptyset(),
62
sigaddset(), sigaction(),
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
#include <errno.h> /* errno, EBADF */
66
67
#define BUFFER_SIZE 256
68
69
#define PDIR "/lib/mandos/plugins.d"
70
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
71
72
const char *argp_program_version = "plugin-runner 1.0";
73
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
74
75
struct plugin;
76
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
79
char **argv;
80
int argc;
81
char **environ;
82
int envc;
83
bool disabled;
84
85
/* Variables used for running processes*/
19
86
pid_t pid;
20
87
int fd;
21
88
char *buffer;
22
int buffer_size;
23
int buffer_length;
24
struct process *next;
25
} process;
26
27
#define BUFFER_SIZE 256
89
size_t buffer_size;
90
size_t buffer_length;
91
bool eof;
92
volatile bool completed;
93
volatile int status;
94
struct plugin *next;
95
} plugin;
96
97
static plugin *plugin_list = NULL;
98
99
/* Gets a existing plugin based on name,
100
or if none is found, creates a new one */
101
static plugin *getplugin(char *name){
102
/* Check for exiting plugin with that name */
103
for (plugin *p = plugin_list; p != NULL; p = p->next){
104
if ((p->name == name)
105
or (p->name and name and (strcmp(p->name, name) == 0))){
106
return p;
107
}
108
}
109
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if (new_plugin == NULL){
112
return NULL;
113
}
114
char *copy_name = NULL;
115
if(name != NULL){
116
copy_name = strdup(name);
117
if(copy_name == NULL){
118
return NULL;
119
}
120
}
121
122
*new_plugin = (plugin) { .name = copy_name,
123
.argc = 1,
124
.disabled = false,
125
.next = plugin_list };
126
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
129
free(copy_name);
130
free(new_plugin);
131
return NULL;
132
}
133
new_plugin->argv[0] = copy_name;
134
new_plugin->argv[1] = NULL;
135
136
new_plugin->environ = malloc(sizeof(char *));
137
if(new_plugin->environ == NULL){
138
free(copy_name);
139
free(new_plugin->argv);
140
free(new_plugin);
141
return NULL;
142
}
143
new_plugin->environ[0] = NULL;
144
145
/* Append the new plugin to the list */
146
plugin_list = new_plugin;
147
return new_plugin;
148
}
149
150
/* Helper function for add_argument and add_environment */
151
static bool add_to_char_array(const char *new, char ***array,
152
int *len){
153
/* Resize the pointed-to array to hold one more pointer */
154
*array = realloc(*array, sizeof(char *)
155
* (size_t) ((*len) + 2));
156
/* Malloc check */
157
if(*array == NULL){
158
return false;
159
}
160
/* Make a copy of the new string */
161
char *copy = strdup(new);
162
if(copy == NULL){
163
return false;
164
}
165
/* Insert the copy */
166
(*array)[*len] = copy;
167
(*len)++;
168
/* Add a new terminating NULL pointer to the last element */
169
(*array)[*len] = NULL;
170
return true;
171
}
172
173
/* Add to a plugin's argument vector */
174
static bool add_argument(plugin *p, const char *arg){
175
if(p == NULL){
176
return false;
177
}
178
return add_to_char_array(arg, &(p->argv), &(p->argc));
179
}
180
181
/* Add to a plugin's environment */
182
static bool add_environment(plugin *p, const char *def){
183
if(p == NULL){
184
return false;
185
}
186
/* namelen = length of name of environment variable */
187
size_t namelen = (size_t)(strchrnul(def, '=') - def);
188
/* Search for this environment variable */
189
for(char **e = p->environ; *e != NULL; e++){
190
if(strncmp(*e, def, namelen+1) == 0){
191
/* Refuse to add an existing variable */
192
return true;
193
}
194
}
195
return add_to_char_array(def, &(p->environ), &(p->envc));
196
}
197
198
/*
199
* Based on the example in the GNU LibC manual chapter 13.13 "File
200
* Descriptor Flags".
201
* *Note File Descriptor Flags:(libc)Descriptor Flags.
202
*/
203
static int set_cloexec_flag(int fd)
204
{
205
int ret = fcntl(fd, F_GETFD, 0);
206
/* If reading the flags failed, return error indication now. */
207
if(ret < 0){
208
return ret;
209
}
210
/* Store modified flag word in the descriptor. */
211
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
212
}
213
214
215
/* Mark processes as completed when they exit, and save their exit
216
status. */
217
void handle_sigchld(__attribute__((unused)) int sig){
218
while(true){
219
plugin *proc = plugin_list;
220
int status;
221
pid_t pid = waitpid(-1, &status, WNOHANG);
222
if(pid == 0){
223
/* Only still running child processes */
224
break;
225
}
226
if(pid == -1){
227
if (errno != ECHILD){
228
perror("waitpid");
229
}
230
/* No child processes */
231
break;
232
}
233
234
/* A child exited, find it in process_list */
235
while(proc != NULL and proc->pid != pid){
236
proc = proc->next;
237
}
238
if(proc == NULL){
239
/* Process not found in process list */
240
continue;
241
}
242
proc->status = status;
243
proc->completed = true;
244
}
245
}
246
247
/* Prints out a password to stdout */
248
bool print_out_password(const char *buffer, size_t length){
249
ssize_t ret;
250
if(length>0 and buffer[length-1] == '\n'){
251
length--;
252
}
253
for(size_t written = 0; written < length; written += (size_t)ret){
254
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
255
length - written));
256
if(ret < 0){
257
return false;
258
}
259
}
260
return true;
261
}
262
263
/* Removes and free a plugin from the plugin list */
264
static void free_plugin(plugin *plugin_node){
265
266
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
267
free(*arg);
268
}
269
free(plugin_node->argv);
270
for(char **env = plugin_node->environ; *env != NULL; env++){
271
free(*env);
272
}
273
free(plugin_node->environ);
274
free(plugin_node->buffer);
275
276
/* Removes the plugin from the singly-linked list */
277
if(plugin_node == plugin_list){
278
/* First one - simple */
279
plugin_list = plugin_list->next;
280
} else {
281
/* Second one or later */
282
for(plugin *p = plugin_list; p != NULL; p = p->next){
283
if(p->next == plugin_node){
284
p->next = plugin_node->next;
285
break;
286
}
287
}
288
}
289
290
free(plugin_node);
291
}
292
293
static void free_plugin_list(void){
294
while(plugin_list != NULL){
295
free_plugin(plugin_list);
296
}
297
}
28
298
29
299
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;
300
char *plugindir = NULL;
301
char *argfile = NULL;
302
FILE *conffp;
303
size_t d_name_len;
304
DIR *dir = NULL;
33
305
struct dirent *dirst;
34
306
struct stat st;
35
fd_set rfds_orig;
307
fd_set rfds_all;
36
308
int ret, maxfd = 0;
37
process *process_list = NULL;
38
39
dir = opendir(plugindir);
40
309
uid_t uid = 65534;
310
gid_t gid = 65534;
311
bool debug = false;
312
int exitstatus = EXIT_SUCCESS;
313
struct sigaction old_sigchld_action;
314
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
315
.sa_flags = SA_NOCLDSTOP };
316
char **custom_argv = NULL;
317
int custom_argc = 0;
318
319
/* Establish a signal handler */
320
sigemptyset(&sigchld_action.sa_mask);
321
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
322
if(ret == -1){
323
perror("sigaddset");
324
exitstatus = EXIT_FAILURE;
325
goto fallback;
326
}
327
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
328
if(ret == -1){
329
perror("sigaction");
330
exitstatus = EXIT_FAILURE;
331
goto fallback;
332
}
333
334
/* The options we understand. */
335
struct argp_option options[] = {
336
{ .name = "global-options", .key = 'g',
337
.arg = "OPTION[,OPTION[,...]]",
338
.doc = "Options passed to all plugins" },
339
{ .name = "global-env", .key = 'e',
340
.arg = "VAR=value",
341
.doc = "Environment variable passed to all plugins" },
342
{ .name = "options-for", .key = 'o',
343
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
344
.doc = "Options passed only to specified plugin" },
345
{ .name = "env-for", .key = 'f',
346
.arg = "PLUGIN:ENV=value",
347
.doc = "Environment variable passed to specified plugin" },
348
{ .name = "disable", .key = 'd',
349
.arg = "PLUGIN",
350
.doc = "Disable a specific plugin", .group = 1 },
351
{ .name = "plugin-dir", .key = 128,
352
.arg = "DIRECTORY",
353
.doc = "Specify a different plugin directory", .group = 2 },
354
{ .name = "config-file", .key = 129,
355
.arg = "FILE",
356
.doc = "Specify a different configuration file", .group = 2 },
357
{ .name = "userid", .key = 130,
358
.arg = "ID", .flags = 0,
359
.doc = "User ID the plugins will run as", .group = 3 },
360
{ .name = "groupid", .key = 131,
361
.arg = "ID", .flags = 0,
362
.doc = "Group ID the plugins will run as", .group = 3 },
363
{ .name = "debug", .key = 132,
364
.doc = "Debug mode", .group = 4 },
365
{ .name = NULL }
366
};
367
368
error_t parse_opt (int key, char *arg, __attribute__((unused))
369
struct argp_state *state) {
370
/* Get the INPUT argument from `argp_parse', which we know is a
371
pointer to our plugin list pointer. */
372
switch (key) {
373
case 'g': /* --global-options */
374
if (arg != NULL){
375
char *p;
376
while((p = strsep(&arg, ",")) != NULL){
377
if(p[0] == '\0'){
378
continue;
379
}
380
if(not add_argument(getplugin(NULL), p)){
381
perror("add_argument");
382
return ARGP_ERR_UNKNOWN;
383
}
384
}
385
}
386
break;
387
case 'e': /* --global-env */
388
if(arg == NULL){
389
break;
390
}
391
{
392
char *envdef = strdup(arg);
393
if(envdef == NULL){
394
break;
395
}
396
if(not add_environment(getplugin(NULL), envdef)){
397
perror("add_environment");
398
}
399
}
400
break;
401
case 'o': /* --options-for */
402
if (arg != NULL){
403
char *p_name = strsep(&arg, ":");
404
if(p_name[0] == '\0'){
405
break;
406
}
407
char *opt = strsep(&arg, ":");
408
if(opt[0] == '\0'){
409
break;
410
}
411
if(opt != NULL){
412
char *p;
413
while((p = strsep(&opt, ",")) != NULL){
414
if(p[0] == '\0'){
415
continue;
416
}
417
if(not add_argument(getplugin(p_name), p)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
420
}
421
}
422
}
423
}
424
break;
425
case 'f': /* --env-for */
426
if(arg == NULL){
427
break;
428
}
429
{
430
char *envdef = strchr(arg, ':');
431
if(envdef == NULL){
432
break;
433
}
434
char *p_name = strndup(arg, (size_t) (envdef-arg));
435
if(p_name == NULL){
436
break;
437
}
438
envdef++;
439
if(not add_environment(getplugin(p_name), envdef)){
440
perror("add_environment");
441
}
442
}
443
break;
444
case 'd': /* --disable */
445
if (arg != NULL){
446
plugin *p = getplugin(arg);
447
if(p == NULL){
448
return ARGP_ERR_UNKNOWN;
449
}
450
p->disabled = true;
451
}
452
break;
453
case 128: /* --plugin-dir */
454
plugindir = strdup(arg);
455
if(plugindir == NULL){
456
perror("strdup");
457
}
458
break;
459
case 129: /* --config-file */
460
argfile = strdup(arg);
461
if(argfile == NULL){
462
perror("strdup");
463
}
464
break;
465
case 130: /* --userid */
466
uid = (uid_t)strtol(arg, NULL, 10);
467
break;
468
case 131: /* --groupid */
469
gid = (gid_t)strtol(arg, NULL, 10);
470
break;
471
case 132: /* --debug */
472
debug = true;
473
break;
474
case ARGP_KEY_ARG:
475
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
476
break;
477
case ARGP_KEY_END:
478
break;
479
default:
480
return ARGP_ERR_UNKNOWN;
481
}
482
return 0;
483
}
484
485
struct argp argp = { .options = options, .parser = parse_opt,
486
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
487
.doc = "Mandos plugin runner -- Run plugins" };
488
489
ret = argp_parse (&argp, argc, argv, 0, 0, NULL);
490
if (ret == ARGP_ERR_UNKNOWN){
491
fprintf(stderr, "Unknown error while parsing arguments\n");
492
exitstatus = EXIT_FAILURE;
493
goto fallback;
494
}
495
496
/* Opens the configfile if aviable */
497
if (argfile == NULL){
498
conffp = fopen(AFILE, "r");
499
} else {
500
conffp = fopen(argfile, "r");
501
}
502
if(conffp != NULL){
503
char *org_line = NULL;
504
char *p, *arg, *new_arg, *line;
505
size_t size = 0;
506
ssize_t sret;
507
const char whitespace_delims[] = " \r\t\f\v\n";
508
const char comment_delim[] = "#";
509
510
custom_argc = 1;
511
custom_argv = malloc(sizeof(char*) * 2);
512
if(custom_argv == NULL){
513
perror("malloc");
514
exitstatus = EXIT_FAILURE;
515
goto fallback;
516
}
517
custom_argv[0] = argv[0];
518
custom_argv[1] = NULL;
519
520
/* for each line in the config file, strip whitespace and ignore
521
commented text */
522
while(true){
523
sret = getline(&org_line, &size, conffp);
524
if(sret == -1){
525
break;
526
}
527
528
line = org_line;
529
arg = strsep(&line, comment_delim);
530
while((p = strsep(&arg, whitespace_delims)) != NULL){
531
if(p[0] == '\0'){
532
continue;
533
}
534
new_arg = strdup(p);
535
if(new_arg == NULL){
536
perror("strdup");
537
exitstatus = EXIT_FAILURE;
538
free(org_line);
539
goto fallback;
540
}
541
542
custom_argc += 1;
543
custom_argv = realloc(custom_argv, sizeof(char *)
544
* ((unsigned int) custom_argc + 1));
545
if(custom_argv == NULL){
546
perror("realloc");
547
exitstatus = EXIT_FAILURE;
548
free(org_line);
549
goto fallback;
550
}
551
custom_argv[custom_argc-1] = new_arg;
552
custom_argv[custom_argc] = NULL;
553
}
554
}
555
free(org_line);
556
} else{
557
/* Check for harmful errors and go to fallback. Other errors might
558
not affect opening plugins */
559
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
560
perror("fopen");
561
exitstatus = EXIT_FAILURE;
562
goto fallback;
563
}
564
}
565
/* If there was any arguments from configuration file,
566
pass them to parser as command arguments */
567
if(custom_argv != NULL){
568
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, NULL);
569
if (ret == ARGP_ERR_UNKNOWN){
570
fprintf(stderr, "Unknown error while parsing arguments\n");
571
exitstatus = EXIT_FAILURE;
572
goto fallback;
573
}
574
}
575
576
if(debug){
577
for(plugin *p = plugin_list; p != NULL; p=p->next){
578
fprintf(stderr, "Plugin: %s has %d arguments\n",
579
p->name ? p->name : "Global", p->argc - 1);
580
for(char **a = p->argv; *a != NULL; a++){
581
fprintf(stderr, "\tArg: %s\n", *a);
582
}
583
fprintf(stderr, "...and %u environment variables\n", p->envc);
584
for(char **a = p->environ; *a != NULL; a++){
585
fprintf(stderr, "\t%s\n", *a);
586
}
587
}
588
}
589
590
/* Strip permissions down to nobody */
591
ret = setuid(uid);
592
if (ret == -1){
593
perror("setuid");
594
}
595
setgid(gid);
596
if (ret == -1){
597
perror("setgid");
598
}
599
600
if (plugindir == NULL){
601
dir = opendir(PDIR);
602
} else {
603
dir = opendir(plugindir);
604
}
605
41
606
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
47
607
perror("Could not open plugin dir");
608
exitstatus = EXIT_FAILURE;
609
goto fallback;
610
}
611
612
/* Set the FD_CLOEXEC flag on the directory, if possible */
613
{
614
int dir_fd = dirfd(dir);
615
if(dir_fd >= 0){
616
ret = set_cloexec_flag(dir_fd);
617
if(ret < 0){
618
perror("set_cloexec_flag");
619
exitstatus = EXIT_FAILURE;
620
goto fallback;
621
}
622
}
623
}
624
625
FD_ZERO(&rfds_all);
626
627
/* Read and execute any executable in the plugin directory*/
48
628
while(true){
49
629
dirst = readdir(dir);
50
630
51
631
// All directory entries have been processed
52
632
if(dirst == NULL){
633
if (errno == EBADF){
634
perror("readdir");
635
exitstatus = EXIT_FAILURE;
636
goto fallback;
637
}
53
638
break;
54
639
}
55
640
56
641
d_name_len = strlen(dirst->d_name);
57
642
58
// Ignore dotfiles and backup files
59
if (dirst->d_name[0] == '.'
60
or dirst->d_name[d_name_len - 1] == '~'){
61
continue;
62
}
63
64
char *filename = malloc(d_name_len + plugindir_len + 1);
65
strcpy(filename, plugindir);
66
strcat(filename, "/");
67
strcat(filename, dirst->d_name);
68
69
stat(filename, &st);
70
71
if (S_ISREG(st.st_mode) and (access(filename, X_OK) == 0)){
72
// Starting a new process to be watched
73
process *new_process = malloc(sizeof(process));
74
int pipefd[2];
75
pipe(pipefd);
76
new_process->pid = fork();
77
if(new_process->pid == 0){
78
/* this is the child process */
643
// Ignore dotfiles, backup files and other junk
644
{
645
bool bad_name = false;
646
647
const char const *bad_prefixes[] = { ".", "#", NULL };
648
649
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
650
".dpkg-old",
651
".dpkg-divert", NULL };
652
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
653
size_t pre_len = strlen(*pre);
654
if((d_name_len >= pre_len)
655
and strncmp((dirst->d_name), *pre, pre_len) == 0){
656
if(debug){
657
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
658
" with bad prefix %s\n", dirst->d_name, *pre);
659
}
660
bad_name = true;
661
break;
662
}
663
}
664
if(bad_name){
665
continue;
666
}
667
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
668
size_t suf_len = strlen(*suf);
669
if((d_name_len >= suf_len)
670
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
671
== 0)){
672
if(debug){
673
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
674
" with bad suffix %s\n", dirst->d_name, *suf);
675
}
676
bad_name = true;
677
break;
678
}
679
}
680
681
if(bad_name){
682
continue;
683
}
684
}
685
686
char *filename;
687
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
688
if(ret < 0){
689
perror("asprintf");
690
continue;
691
}
692
693
ret = stat(filename, &st);
694
if (ret == -1){
695
perror("stat");
696
free(filename);
697
continue;
698
}
699
700
/* Ignore non-executable files */
701
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
702
if(debug){
703
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
704
" with bad type or mode\n", filename);
705
}
706
free(filename);
707
continue;
708
}
709
710
plugin *p = getplugin(dirst->d_name);
711
if(p == NULL){
712
perror("getplugin");
713
free(filename);
714
continue;
715
}
716
if(p->disabled){
717
if(debug){
718
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
719
dirst->d_name);
720
}
721
free(filename);
722
continue;
723
}
724
{
725
/* Add global arguments to argument list for this plugin */
726
plugin *g = getplugin(NULL);
727
if(g != NULL){
728
for(char **a = g->argv + 1; *a != NULL; a++){
729
if(not add_argument(p, *a)){
730
perror("add_argument");
731
}
732
}
733
/* Add global environment variables */
734
for(char **e = g->environ; *e != NULL; e++){
735
if(not add_environment(p, *e)){
736
perror("add_environment");
737
}
738
}
739
}
740
}
741
/* If this plugin has any environment variables, we will call
742
using execve and need to duplicate the environment from this
743
process, too. */
744
if(p->environ[0] != NULL){
745
for(char **e = environ; *e != NULL; e++){
746
char *copy = strdup(*e);
747
if(copy == NULL){
748
perror("strdup");
749
continue;
750
}
751
if(not add_environment(p, copy)){
752
perror("add_environment");
753
}
754
}
755
}
756
757
int pipefd[2];
758
ret = pipe(pipefd);
759
if (ret == -1){
760
perror("pipe");
761
exitstatus = EXIT_FAILURE;
762
goto fallback;
763
}
764
/* Ask OS to automatic close the pipe on exec */
765
ret = set_cloexec_flag(pipefd[0]);
766
if(ret < 0){
767
perror("set_cloexec_flag");
768
exitstatus = EXIT_FAILURE;
769
goto fallback;
770
}
771
ret = set_cloexec_flag(pipefd[1]);
772
if(ret < 0){
773
perror("set_cloexec_flag");
774
exitstatus = EXIT_FAILURE;
775
goto fallback;
776
}
777
/* Block SIGCHLD until process is safely in process list */
778
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
779
if(ret < 0){
780
perror("sigprocmask");
781
exitstatus = EXIT_FAILURE;
782
goto fallback;
783
}
784
// Starting a new process to be watched
785
pid_t pid = fork();
786
if(pid == -1){
787
perror("fork");
788
exitstatus = EXIT_FAILURE;
789
goto fallback;
790
}
791
if(pid == 0){
792
/* this is the child process */
793
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
794
if(ret < 0){
795
perror("sigaction");
796
_exit(EXIT_FAILURE);
797
}
798
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
799
if(ret < 0){
800
perror("sigprocmask");
801
_exit(EXIT_FAILURE);
802
}
803
804
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
805
if(ret == -1){
806
perror("dup2");
807
_exit(EXIT_FAILURE);
808
}
809
810
if(dirfd(dir) < 0){
811
/* If dir has no file descriptor, we could not set FD_CLOEXEC
812
above and must now close it manually here. */
79
813
closedir(dir);
80
close(pipefd[0]); /* close unused read end of pipe */
81
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
82
/* create a new modified argument list */
83
char **new_argv = malloc(sizeof(char *) * argc + 1);
84
new_argv[0] = filename;
85
for(int i = 1; i < argc; i++){
86
new_argv[i] = argv[i];
87
}
88
new_argv[argc] = NULL;
89
if(execv(filename, new_argv) < 0){
90
perror(argv[0]);
91
close(pipefd[1]);
92
exit(EXIT_FAILURE);
93
}
94
/* no return */
95
}
96
close(pipefd[1]); /* close unused write end of pipe */
97
new_process->fd = pipefd[0];
98
new_process->buffer = malloc(BUFFER_SIZE);
99
if (new_process->buffer == NULL){
100
perror(argv[0]);
101
goto end;
102
}
103
new_process->buffer_size = BUFFER_SIZE;
104
new_process->buffer_length = 0;
105
FD_SET(new_process->fd, &rfds_orig);
106
107
if (maxfd < new_process->fd){
108
maxfd = new_process->fd;
109
}
110
111
//List handling
112
new_process->next = process_list;
113
process_list = new_process;
114
}
814
}
815
if(p->environ[0] == NULL){
816
if(execv(filename, p->argv) < 0){
817
perror("execv");
818
_exit(EXIT_FAILURE);
819
}
820
} else {
821
if(execve(filename, p->argv, p->environ) < 0){
822
perror("execve");
823
_exit(EXIT_FAILURE);
824
}
825
}
826
/* no return */
827
}
828
/* Parent process */
829
close(pipefd[1]); /* Close unused write end of pipe */
830
free(filename);
831
plugin *new_plugin = getplugin(dirst->d_name);
832
if (new_plugin == NULL){
833
perror("getplugin");
834
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
835
if(ret < 0){
836
perror("sigprocmask");
837
}
838
exitstatus = EXIT_FAILURE;
839
goto fallback;
840
}
841
842
new_plugin->pid = pid;
843
new_plugin->fd = pipefd[0];
844
845
/* Unblock SIGCHLD so signal handler can be run if this process
846
has already completed */
847
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
848
if(ret < 0){
849
perror("sigprocmask");
850
exitstatus = EXIT_FAILURE;
851
goto fallback;
852
}
853
854
FD_SET(new_plugin->fd, &rfds_all);
855
856
if (maxfd < new_plugin->fd){
857
maxfd = new_plugin->fd;
858
}
859
115
860
}
116
861
117
862
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
}
863
dir = NULL;
864
865
for(plugin *p = plugin_list; p != NULL; p = p->next){
866
if(p->pid != 0){
178
867
break;
179
868
}
180
}
181
return EXIT_SUCCESS;
869
if(p->next == NULL){
870
fprintf(stderr, "No plugin processes started. Incorrect plugin"
871
" directory?\n");
872
free_plugin_list();
873
}
874
}
875
876
/* Main loop while running plugins exist */
877
while(plugin_list){
878
fd_set rfds = rfds_all;
879
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
880
if (select_ret == -1){
881
perror("select");
882
exitstatus = EXIT_FAILURE;
883
goto fallback;
884
}
885
/* OK, now either a process completed, or something can be read
886
from one of them */
887
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
888
/* Is this process completely done? */
889
if(proc->eof and proc->completed){
890
/* Only accept the plugin output if it exited cleanly */
891
if(not WIFEXITED(proc->status)
892
or WEXITSTATUS(proc->status) != 0){
893
/* Bad exit by plugin */
894
895
if(debug){
896
if(WIFEXITED(proc->status)){
897
fprintf(stderr, "Plugin %u exited with status %d\n",
898
(unsigned int) (proc->pid),
899
WEXITSTATUS(proc->status));
900
} else if(WIFSIGNALED(proc->status)) {
901
fprintf(stderr, "Plugin %u killed by signal %d\n",
902
(unsigned int) (proc->pid),
903
WTERMSIG(proc->status));
904
} else if(WCOREDUMP(proc->status)){
905
fprintf(stderr, "Plugin %d dumped core\n",
906
(unsigned int) (proc->pid));
907
}
908
}
909
910
/* Remove the plugin */
911
FD_CLR(proc->fd, &rfds_all);
912
913
/* Block signal while modifying process_list */
914
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
915
if(ret < 0){
916
perror("sigprocmask");
917
exitstatus = EXIT_FAILURE;
918
goto fallback;
919
}
920
free_plugin(proc);
921
/* We are done modifying process list, so unblock signal */
922
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
923
NULL);
924
if(ret < 0){
925
perror("sigprocmask");
926
exitstatus = EXIT_FAILURE;
927
goto fallback;
928
}
929
930
if(plugin_list == NULL){
931
break;
932
}
933
continue;
934
}
935
936
/* This process exited nicely, so print its buffer */
937
938
bool bret = print_out_password(proc->buffer,
939
proc->buffer_length);
940
if(not bret){
941
perror("print_out_password");
942
exitstatus = EXIT_FAILURE;
943
}
944
goto fallback;
945
}
946
947
/* This process has not completed. Does it have any output? */
948
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
949
/* This process had nothing to say at this time */
950
continue;
951
}
952
/* Before reading, make the process' data buffer large enough */
953
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
954
proc->buffer = realloc(proc->buffer, proc->buffer_size
955
+ (size_t) BUFFER_SIZE);
956
if (proc->buffer == NULL){
957
perror("malloc");
958
exitstatus = EXIT_FAILURE;
959
goto fallback;
960
}
961
proc->buffer_size += BUFFER_SIZE;
962
}
963
/* Read from the process */
964
ret = read(proc->fd, proc->buffer + proc->buffer_length,
965
BUFFER_SIZE);
966
if(ret < 0){
967
/* Read error from this process; ignore the error */
968
continue;
969
}
970
if(ret == 0){
971
/* got EOF */
972
proc->eof = true;
973
} else {
974
proc->buffer_length += (size_t) ret;
975
}
976
}
977
}
978
979
980
fallback:
981
982
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
983
/* Fallback if all plugins failed, none are found or an error
984
occured */
985
bool bret;
986
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
987
char *passwordbuffer = getpass("Password: ");
988
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
989
if(not bret){
990
perror("print_out_password");
991
exitstatus = EXIT_FAILURE;
992
}
993
}
994
995
/* Restore old signal handler */
996
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
997
if(ret == -1){
998
perror("sigaction");
999
exitstatus = EXIT_FAILURE;
1000
}
1001
1002
if(custom_argv != NULL){
1003
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1004
free(*arg);
1005
}
1006
free(custom_argv);
1007
}
1008
1009
if(dir != NULL){
1010
closedir(dir);
1011
}
1012
1013
/* Free the process list and kill the processes */
1014
for(plugin *p = plugin_list; p != NULL; p = p->next){
1015
if(p->pid != 0){
1016
close(p->fd);
1017
ret = kill(p->pid, SIGTERM);
1018
if(ret == -1 and errno != ESRCH){
1019
/* Set-uid proccesses might not get closed */
1020
perror("kill");
1021
}
1022
}
1023
}
1024
1025
/* Wait for any remaining child processes to terminate */
1026
do{
1027
ret = wait(NULL);
1028
} while(ret >= 0);
1029
if(errno != ECHILD){
1030
perror("wait");
1031
}
1032
1033
free_plugin_list();
1034
1035
free(plugindir);
1036
free(argfile);
1037
1038
return exitstatus;
182
1039
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0