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- Committer: Björn Påhlsson
- Date: 2008-08-25 01:40:19 UTC
- mto: (237.7.1 mandos) (24.1.154 mandos)
- mto: This revision was merged to the branch mainline in revision 107.
- Revision ID: belorn@braxen-20080825014019-p8ji8qn1bga4koao
transformed a function to a part of main
- files added:
- COPYING
- 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 */
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
#define ARGFILE "/conf/conf.d/mandos/plugin-runner.conf"
69
70
const char *argp_program_version = "plugin-runner 1.0";
71
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
15
72
16
73
struct process;
17
74
19
76
pid_t pid;
20
77
int fd;
21
78
char *buffer;
22
int buffer_size;
23
int buffer_length;
79
size_t buffer_size;
80
size_t buffer_length;
81
bool eof;
82
volatile bool completed;
83
volatile int status;
24
84
struct process *next;
25
85
} process;
26
86
27
#define BUFFER_SIZE 256
87
typedef struct plugin{
88
char *name; /* can be NULL or any plugin name */
89
char **argv;
90
int argc;
91
char **environ;
92
int envc;
93
bool disabled;
94
struct plugin *next;
95
} plugin;
96
97
static plugin *getplugin(char *name, plugin **plugin_list){
98
for (plugin *p = *plugin_list; p != NULL; p = p->next){
99
if ((p->name == name)
100
or (p->name and name and (strcmp(p->name, name) == 0))){
101
return p;
102
}
103
}
104
/* Create a new plugin */
105
plugin *new_plugin = malloc(sizeof(plugin));
106
if (new_plugin == NULL){
107
return NULL;
108
}
109
char *copy_name = NULL;
110
if(name != NULL){
111
copy_name = strdup(name);
112
if(copy_name == NULL){
113
return NULL;
114
}
115
}
116
117
*new_plugin = (plugin) { .name = copy_name,
118
.argc = 1,
119
.envc = 0,
120
.disabled = false,
121
.next = *plugin_list };
122
123
new_plugin->argv = malloc(sizeof(char *) * 2);
124
if (new_plugin->argv == NULL){
125
free(copy_name);
126
free(new_plugin);
127
return NULL;
128
}
129
new_plugin->argv[0] = copy_name;
130
new_plugin->argv[1] = NULL;
131
132
new_plugin->environ = malloc(sizeof(char *));
133
if(new_plugin->environ == NULL){
134
free(copy_name);
135
free(new_plugin->argv);
136
free(new_plugin);
137
return NULL;
138
}
139
new_plugin->environ[0] = NULL;
140
/* Append the new plugin to the list */
141
*plugin_list = new_plugin;
142
return new_plugin;
143
}
144
145
/* Helper function for add_argument and add_environment */
146
static bool add_to_char_array(const char *new, char ***array,
147
int *len){
148
/* Resize the pointed-to array to hold one more pointer */
149
*array = realloc(*array, sizeof(char *)
150
* (size_t) ((*len) + 2));
151
/* Malloc check */
152
if(*array == NULL){
153
return false;
154
}
155
/* Make a copy of the new string */
156
char *copy = strdup(new);
157
if(copy == NULL){
158
return false;
159
}
160
/* Insert the copy */
161
(*array)[*len] = copy;
162
(*len)++;
163
/* Add a new terminating NULL pointer to the last element */
164
(*array)[*len] = NULL;
165
return true;
166
}
167
168
/* Add to a plugin's argument vector */
169
static bool add_argument(plugin *p, const char *arg){
170
if(p == NULL){
171
return false;
172
}
173
return add_to_char_array(arg, &(p->argv), &(p->argc));
174
}
175
176
/* Add to a plugin's environment */
177
static bool add_environment(plugin *p, const char *def){
178
if(p == NULL){
179
return false;
180
}
181
return add_to_char_array(def, &(p->environ), &(p->envc));
182
}
183
184
185
/*
186
* Based on the example in the GNU LibC manual chapter 13.13 "File
187
* Descriptor Flags".
188
* *Note File Descriptor Flags:(libc)Descriptor Flags.
189
*/
190
static int set_cloexec_flag(int fd)
191
{
192
int ret = fcntl(fd, F_GETFD, 0);
193
/* If reading the flags failed, return error indication now. */
194
if(ret < 0){
195
return ret;
196
}
197
/* Store modified flag word in the descriptor. */
198
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
199
}
200
201
process *process_list = NULL;
202
203
/* Mark processes as completed when they exit, and save their exit
204
status. */
205
void handle_sigchld(__attribute__((unused)) int sig){
206
while(true){
207
process *proc = process_list;
208
int status;
209
pid_t pid = waitpid(-1, &status, WNOHANG);
210
if(pid == 0){
211
/* Only still running child processes */
212
break;
213
}
214
if(pid == -1){
215
if (errno != ECHILD){
216
perror("waitpid");
217
}
218
/* No child processes */
219
break;
220
}
221
222
/* A child exited, find it in process_list */
223
while(proc != NULL and proc->pid != pid){
224
proc = proc->next;
225
}
226
if(proc == NULL){
227
/* Process not found in process list */
228
continue;
229
}
230
proc->status = status;
231
proc->completed = true;
232
}
233
}
234
235
bool print_out_password(const char *buffer, size_t length){
236
ssize_t ret;
237
if(length>0 and buffer[length-1] == '\n'){
238
length--;
239
}
240
for(size_t written = 0; written < length; written += (size_t)ret){
241
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
242
length - written));
243
if(ret < 0){
244
return false;
245
}
246
}
247
return true;
248
}
249
250
static void free_plugin_list(plugin *plugin_list){
251
for(plugin *next; plugin_list != NULL; plugin_list = next){
252
next = plugin_list->next;
253
for(char **arg = plugin_list->argv; *arg != NULL; arg++){
254
free(*arg);
255
}
256
free(plugin_list->argv);
257
for(char **env = plugin_list->environ; *env != NULL; env++){
258
free(*env);
259
}
260
free(plugin_list->environ);
261
free(plugin_list);
262
}
263
}
28
264
29
265
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;
266
const char *plugindir = "/lib/mandos/plugins.d";
267
const char *argfile = ARGFILE;
268
FILE *conffp;
269
size_t d_name_len;
270
DIR *dir = NULL;
33
271
struct dirent *dirst;
34
272
struct stat st;
35
fd_set rfds_orig;
273
fd_set rfds_all;
36
274
int ret, maxfd = 0;
37
process *process_list = NULL;
275
uid_t uid = 65534;
276
gid_t gid = 65534;
277
bool debug = false;
278
int exitstatus = EXIT_SUCCESS;
279
struct sigaction old_sigchld_action;
280
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
281
.sa_flags = SA_NOCLDSTOP };
282
char **custom_argv = NULL;
283
int custom_argc = 0;
284
285
/* Establish a signal handler */
286
sigemptyset(&sigchld_action.sa_mask);
287
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
288
if(ret == -1){
289
perror("sigaddset");
290
exitstatus = EXIT_FAILURE;
291
goto fallback;
292
}
293
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
294
if(ret == -1){
295
perror("sigaction");
296
exitstatus = EXIT_FAILURE;
297
goto fallback;
298
}
299
300
/* The options we understand. */
301
struct argp_option options[] = {
302
{ .name = "global-options", .key = 'g',
303
.arg = "OPTION[,OPTION[,...]]",
304
.doc = "Options passed to all plugins" },
305
{ .name = "global-envs", .key = 'e',
306
.arg = "VAR=value",
307
.doc = "Environment variable passed to all plugins" },
308
{ .name = "options-for", .key = 'o',
309
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
310
.doc = "Options passed only to specified plugin" },
311
{ .name = "envs-for", .key = 'f',
312
.arg = "PLUGIN:ENV=value",
313
.doc = "Environment variable passed to specified plugin" },
314
{ .name = "disable", .key = 'd',
315
.arg = "PLUGIN",
316
.doc = "Disable a specific plugin", .group = 1 },
317
{ .name = "plugin-dir", .key = 128,
318
.arg = "DIRECTORY",
319
.doc = "Specify a different plugin directory", .group = 2 },
320
{ .name = "userid", .key = 129,
321
.arg = "ID", .flags = 0,
322
.doc = "User ID the plugins will run as", .group = 2 },
323
{ .name = "groupid", .key = 130,
324
.arg = "ID", .flags = 0,
325
.doc = "Group ID the plugins will run as", .group = 2 },
326
{ .name = "debug", .key = 131,
327
.doc = "Debug mode", .group = 3 },
328
{ .name = NULL }
329
};
330
331
error_t parse_opt (int key, char *arg, struct argp_state *state) {
332
/* Get the INPUT argument from `argp_parse', which we know is a
333
pointer to our plugin list pointer. */
334
plugin **plugins = state->input;
335
switch (key) {
336
case 'g':
337
if (arg != NULL){
338
char *p;
339
while((p = strsep(&arg, ",")) != NULL){
340
if(p[0] == '\0'){
341
continue;
342
}
343
if(not add_argument(getplugin(NULL, plugins), p)){
344
perror("add_argument");
345
return ARGP_ERR_UNKNOWN;
346
}
347
}
348
}
349
break;
350
case 'e':
351
if(arg == NULL){
352
break;
353
}
354
{
355
char *envdef = strdup(arg);
356
if(envdef == NULL){
357
break;
358
}
359
if(not add_environment(getplugin(NULL, plugins), envdef)){
360
perror("add_environment");
361
}
362
}
363
break;
364
case 'o':
365
if (arg != NULL){
366
char *p_name = strsep(&arg, ":");
367
if(p_name[0] == '\0'){
368
break;
369
}
370
char *opt = strsep(&arg, ":");
371
if(opt[0] == '\0'){
372
break;
373
}
374
if(opt != NULL){
375
char *p;
376
while((p = strsep(&opt, ",")) != NULL){
377
if(p[0] == '\0'){
378
continue;
379
}
380
if(not add_argument(getplugin(p_name, plugins), p)){
381
perror("add_argument");
382
return ARGP_ERR_UNKNOWN;
383
}
384
}
385
}
386
}
387
break;
388
case 'f':
389
if(arg == NULL){
390
break;
391
}
392
{
393
char *envdef = strchr(arg, ':');
394
if(envdef == NULL){
395
break;
396
}
397
char *p_name = strndup(arg, (size_t) (envdef-arg));
398
if(p_name == NULL){
399
break;
400
}
401
envdef++;
402
if(not add_environment(getplugin(p_name, plugins), envdef)){
403
perror("add_environment");
404
}
405
}
406
break;
407
case 'd':
408
if (arg != NULL){
409
plugin *p = getplugin(arg, plugins);
410
if(p == NULL){
411
return ARGP_ERR_UNKNOWN;
412
}
413
p->disabled = true;
414
}
415
break;
416
case 128:
417
plugindir = arg;
418
break;
419
case 129:
420
uid = (uid_t)strtol(arg, NULL, 10);
421
break;
422
case 130:
423
gid = (gid_t)strtol(arg, NULL, 10);
424
break;
425
case 131:
426
debug = true;
427
break;
428
case ARGP_KEY_ARG:
429
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
430
break;
431
case ARGP_KEY_END:
432
break;
433
default:
434
return ARGP_ERR_UNKNOWN;
435
}
436
return 0;
437
}
438
439
plugin *plugin_list = NULL;
440
441
struct argp argp = { .options = options, .parser = parse_opt,
442
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
443
.doc = "Mandos plugin runner -- Run plugins" };
444
445
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
446
if (ret == ARGP_ERR_UNKNOWN){
447
fprintf(stderr, "Unknown error while parsing arguments\n");
448
exitstatus = EXIT_FAILURE;
449
goto fallback;
450
}
451
452
conffp = fopen(argfile, "r");
453
if(conffp != NULL){
454
char *org_line = NULL;
455
char *p, *arg, *new_arg, *line;
456
size_t size = 0;
457
ssize_t sret;
458
const char whitespace_delims[] = " \r\t\f\v\n";
459
const char comment_delim[] = "#";
460
461
custom_argc = 1;
462
custom_argv = malloc(sizeof(char*) * 2);
463
if(custom_argv == NULL){
464
perror("malloc");
465
exitstatus = EXIT_FAILURE;
466
goto fallback;
467
}
468
custom_argv[0] = argv[0];
469
custom_argv[1] = NULL;
470
471
while(true){
472
sret = getline(&org_line, &size, conffp);
473
if(sret == -1){
474
break;
475
}
476
477
line = org_line;
478
arg = strsep(&line, comment_delim);
479
while((p = strsep(&arg, whitespace_delims)) != NULL){
480
if(p[0] == '\0'){
481
continue;
482
}
483
new_arg = strdup(p);
484
485
custom_argc += 1;
486
custom_argv = realloc(custom_argv, sizeof(char *)
487
* ((unsigned int) custom_argc + 1));
488
if(custom_argv == NULL){
489
perror("realloc");
490
exitstatus = EXIT_FAILURE;
491
free(org_line);
492
goto fallback;
493
}
494
custom_argv[custom_argc-1] = new_arg;
495
custom_argv[custom_argc] = NULL;
496
}
497
}
498
free(org_line);
499
} else{
500
/* Check for harmful errors and go to fallback. Other errors might
501
not affect opening plugins */
502
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
503
perror("fopen");
504
exitstatus = EXIT_FAILURE;
505
goto fallback;
506
}
507
}
508
509
if(custom_argv != NULL){
510
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
511
if (ret == ARGP_ERR_UNKNOWN){
512
fprintf(stderr, "Unknown error while parsing arguments\n");
513
exitstatus = EXIT_FAILURE;
514
goto fallback;
515
}
516
}
517
518
if(debug){
519
for(plugin *p = plugin_list; p != NULL; p=p->next){
520
fprintf(stderr, "Plugin: %s has %d arguments\n",
521
p->name ? p->name : "Global", p->argc - 1);
522
for(char **a = p->argv; *a != NULL; a++){
523
fprintf(stderr, "\tArg: %s\n", *a);
524
}
525
fprintf(stderr, "...and %u environment variables\n", p->envc);
526
for(char **a = p->environ; *a != NULL; a++){
527
fprintf(stderr, "\t%s\n", *a);
528
}
529
}
530
}
531
532
ret = setuid(uid);
533
if (ret == -1){
534
perror("setuid");
535
}
536
537
setgid(gid);
538
if (ret == -1){
539
perror("setgid");
540
}
38
541
39
542
dir = opendir(plugindir);
40
41
543
if(dir == NULL){
42
fprintf(stderr, "Can not open directory\n");
43
return EXIT_FAILURE;
44
}
45
46
FD_ZERO(&rfds_orig);
544
perror("Could not open plugin dir");
545
exitstatus = EXIT_FAILURE;
546
goto fallback;
547
}
548
549
/* Set the FD_CLOEXEC flag on the directory, if possible */
550
{
551
int dir_fd = dirfd(dir);
552
if(dir_fd >= 0){
553
ret = set_cloexec_flag(dir_fd);
554
if(ret < 0){
555
perror("set_cloexec_flag");
556
exitstatus = EXIT_FAILURE;
557
goto fallback;
558
}
559
}
560
}
561
562
FD_ZERO(&rfds_all);
47
563
48
564
while(true){
49
565
dirst = readdir(dir);
50
566
51
567
// All directory entries have been processed
52
568
if(dirst == NULL){
569
if (errno == EBADF){
570
perror("readdir");
571
exitstatus = EXIT_FAILURE;
572
goto fallback;
573
}
53
574
break;
54
575
}
55
576
56
577
d_name_len = strlen(dirst->d_name);
57
578
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 */
579
// Ignore dotfiles, backup files and other junk
580
{
581
bool bad_name = false;
582
583
const char const *bad_prefixes[] = { ".", "#", NULL };
584
585
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
586
".dpkg-old",
587
".dpkg-divert", NULL };
588
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
589
size_t pre_len = strlen(*pre);
590
if((d_name_len >= pre_len)
591
and strncmp((dirst->d_name), *pre, pre_len) == 0){
592
if(debug){
593
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
594
" with bad prefix %s\n", dirst->d_name, *pre);
595
}
596
bad_name = true;
597
break;
598
}
599
}
600
601
if(bad_name){
602
continue;
603
}
604
605
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
606
size_t suf_len = strlen(*suf);
607
if((d_name_len >= suf_len)
608
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
609
== 0)){
610
if(debug){
611
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
612
" with bad suffix %s\n", dirst->d_name, *suf);
613
}
614
bad_name = true;
615
break;
616
}
617
}
618
619
if(bad_name){
620
continue;
621
}
622
}
623
624
char *filename;
625
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
626
if(ret < 0){
627
perror("asprintf");
628
continue;
629
}
630
631
ret = stat(filename, &st);
632
if (ret == -1){
633
perror("stat");
634
free(filename);
635
continue;
636
}
637
638
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
639
if(debug){
640
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
641
" with bad type or mode\n", filename);
642
}
643
free(filename);
644
continue;
645
}
646
plugin *p = getplugin(dirst->d_name, &plugin_list);
647
if(p == NULL){
648
perror("getplugin");
649
free(filename);
650
continue;
651
}
652
if(p->disabled){
653
if(debug){
654
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
655
dirst->d_name);
656
}
657
free(filename);
658
continue;
659
}
660
{
661
/* Add global arguments to argument list for this plugin */
662
plugin *g = getplugin(NULL, &plugin_list);
663
if(g != NULL){
664
for(char **a = g->argv + 1; *a != NULL; a++){
665
if(not add_argument(p, *a)){
666
perror("add_argument");
667
}
668
}
669
/* Add global environment variables */
670
for(char **e = g->environ; *e != NULL; e++){
671
if(not add_environment(p, *e)){
672
perror("add_environment");
673
}
674
}
675
}
676
}
677
/* If this plugin has any environment variables, we will call
678
using execve and need to duplicate the environment from this
679
process, too. */
680
if(p->environ[0] != NULL){
681
for(char **e = environ; *e != NULL; e++){
682
char *copy = strdup(*e);
683
if(copy == NULL){
684
perror("strdup");
685
continue;
686
}
687
if(not add_environment(p, copy)){
688
perror("add_environment");
689
}
690
}
691
}
692
693
int pipefd[2];
694
ret = pipe(pipefd);
695
if (ret == -1){
696
perror("pipe");
697
exitstatus = EXIT_FAILURE;
698
goto fallback;
699
}
700
ret = set_cloexec_flag(pipefd[0]);
701
if(ret < 0){
702
perror("set_cloexec_flag");
703
exitstatus = EXIT_FAILURE;
704
goto fallback;
705
}
706
ret = set_cloexec_flag(pipefd[1]);
707
if(ret < 0){
708
perror("set_cloexec_flag");
709
exitstatus = EXIT_FAILURE;
710
goto fallback;
711
}
712
/* Block SIGCHLD until process is safely in process list */
713
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
714
if(ret < 0){
715
perror("sigprocmask");
716
exitstatus = EXIT_FAILURE;
717
goto fallback;
718
}
719
// Starting a new process to be watched
720
pid_t pid = fork();
721
if(pid == -1){
722
perror("fork");
723
exitstatus = EXIT_FAILURE;
724
goto fallback;
725
}
726
if(pid == 0){
727
/* this is the child process */
728
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
729
if(ret < 0){
730
perror("sigaction");
731
_exit(EXIT_FAILURE);
732
}
733
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
734
if(ret < 0){
735
perror("sigprocmask");
736
_exit(EXIT_FAILURE);
737
}
738
739
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
740
if(ret == -1){
741
perror("dup2");
742
_exit(EXIT_FAILURE);
743
}
744
745
if(dirfd(dir) < 0){
746
/* If dir has no file descriptor, we could not set FD_CLOEXEC
747
above and must now close it manually here. */
79
748
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
}
749
}
750
if(p->environ[0] == NULL){
751
if(execv(filename, p->argv) < 0){
752
perror("execv");
753
_exit(EXIT_FAILURE);
754
}
755
} else {
756
if(execve(filename, p->argv, p->environ) < 0){
757
perror("execve");
758
_exit(EXIT_FAILURE);
759
}
760
}
761
/* no return */
762
}
763
/* parent process */
764
free(filename);
765
close(pipefd[1]); /* close unused write end of pipe */
766
process *new_process = malloc(sizeof(process));
767
if (new_process == NULL){
768
perror("malloc");
769
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
770
if(ret < 0){
771
perror("sigprocmask");
772
}
773
exitstatus = EXIT_FAILURE;
774
goto fallback;
775
}
776
777
*new_process = (struct process){ .pid = pid,
778
.fd = pipefd[0],
779
.next = process_list };
780
// List handling
781
process_list = new_process;
782
/* Unblock SIGCHLD so signal handler can be run if this process
783
has already completed */
784
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
785
if(ret < 0){
786
perror("sigprocmask");
787
exitstatus = EXIT_FAILURE;
788
goto fallback;
789
}
790
791
FD_SET(new_process->fd, &rfds_all);
792
793
if (maxfd < new_process->fd){
794
maxfd = new_process->fd;
795
}
796
115
797
}
116
798
799
free_plugin_list(plugin_list);
800
plugin_list = NULL;
801
117
802
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;
803
dir = NULL;
804
805
if (process_list == NULL){
806
fprintf(stderr, "No plugin processes started. Incorrect plugin"
807
" directory?\n");
808
process_list = NULL;
809
}
810
while(process_list){
811
fd_set rfds = rfds_all;
812
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
813
if (select_ret == -1){
814
perror("select");
815
exitstatus = EXIT_FAILURE;
816
goto fallback;
817
}
818
/* OK, now either a process completed, or something can be read
819
from one of them */
820
for(process *proc = process_list; proc ; proc = proc->next){
821
/* Is this process completely done? */
822
if(proc->eof and proc->completed){
823
/* Only accept the plugin output if it exited cleanly */
824
if(not WIFEXITED(proc->status)
825
or WEXITSTATUS(proc->status) != 0){
826
/* Bad exit by plugin */
827
if(debug){
828
if(WIFEXITED(proc->status)){
829
fprintf(stderr, "Plugin %u exited with status %d\n",
830
(unsigned int) (proc->pid),
831
WEXITSTATUS(proc->status));
832
} else if(WIFSIGNALED(proc->status)) {
833
fprintf(stderr, "Plugin %u killed by signal %d\n",
834
(unsigned int) (proc->pid),
835
WTERMSIG(proc->status));
836
} else if(WCOREDUMP(proc->status)){
837
fprintf(stderr, "Plugin %d dumped core\n",
838
(unsigned int) (proc->pid));
140
839
}
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);
840
}
841
/* Remove the plugin */
842
FD_CLR(proc->fd, &rfds_all);
843
/* Block signal while modifying process_list */
844
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
845
if(ret < 0){
846
perror("sigprocmask");
847
exitstatus = EXIT_FAILURE;
848
goto fallback;
849
}
850
/* Delete this process entry from the list */
851
if(process_list == proc){
852
/* First one - simple */
853
process_list = proc->next;
854
} else {
855
/* Second one or later */
856
for(process *p = process_list; p != NULL; p = p->next){
857
if(p->next == proc){
858
p->next = proc->next;
859
break;
155
860
}
156
861
}
157
862
}
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
}
178
break;
179
}
180
}
181
return EXIT_SUCCESS;
863
/* We are done modifying process list, so unblock signal */
864
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
865
NULL);
866
if(ret < 0){
867
perror("sigprocmask");
868
}
869
free(proc->buffer);
870
free(proc);
871
/* We deleted this process from the list, so we can't go
872
proc->next. Therefore, start over from the beginning of
873
the process list */
874
break;
875
}
876
/* This process exited nicely, so print its buffer */
877
878
bool bret = print_out_password(proc->buffer,
879
proc->buffer_length);
880
if(not bret){
881
perror("print_out_password");
882
exitstatus = EXIT_FAILURE;
883
}
884
goto fallback;
885
}
886
/* This process has not completed. Does it have any output? */
887
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
888
/* This process had nothing to say at this time */
889
continue;
890
}
891
/* Before reading, make the process' data buffer large enough */
892
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
893
proc->buffer = realloc(proc->buffer, proc->buffer_size
894
+ (size_t) BUFFER_SIZE);
895
if (proc->buffer == NULL){
896
perror("malloc");
897
exitstatus = EXIT_FAILURE;
898
goto fallback;
899
}
900
proc->buffer_size += BUFFER_SIZE;
901
}
902
/* Read from the process */
903
ret = read(proc->fd, proc->buffer + proc->buffer_length,
904
BUFFER_SIZE);
905
if(ret < 0){
906
/* Read error from this process; ignore the error */
907
continue;
908
}
909
if(ret == 0){
910
/* got EOF */
911
proc->eof = true;
912
} else {
913
proc->buffer_length += (size_t) ret;
914
}
915
}
916
}
917
918
919
fallback:
920
921
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
922
/* Fallback if all plugins failed, none are found or an error
923
occured */
924
bool bret;
925
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
926
char *passwordbuffer = getpass("Password: ");
927
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
928
if(not bret){
929
perror("print_out_password");
930
exitstatus = EXIT_FAILURE;
931
}
932
}
933
934
/* Restore old signal handler */
935
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
936
if(ret == -1){
937
perror("sigaction");
938
exitstatus = EXIT_FAILURE;
939
}
940
941
if(custom_argv != NULL){
942
for(char **arg = custom_argv+1; *arg != NULL; arg++){
943
free(*arg);
944
}
945
free(custom_argv);
946
}
947
free_plugin_list(plugin_list);
948
949
if(dir != NULL){
950
closedir(dir);
951
}
952
953
/* Free the process list and kill the processes */
954
for(process *next; process_list != NULL; process_list = next){
955
next = process_list->next;
956
close(process_list->fd);
957
ret = kill(process_list->pid, SIGTERM);
958
if(ret == -1 and errno != ESRCH){
959
/* set-uid proccesses migth not get closed */
960
perror("kill");
961
}
962
free(process_list->buffer);
963
free(process_list);
964
}
965
966
/* Wait for any remaining child processes to terminate */
967
do{
968
ret = wait(NULL);
969
} while(ret >= 0);
970
if(errno != ECHILD){
971
perror("wait");
972
}
973
974
return exitstatus;
182
975
}
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0