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 */
18
typedef struct process{
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
3
* Mandos plugin runner - Run Mandos plugins
5
* Copyright © 2008-2018 Teddy Hogeborn
6
* Copyright © 2008-2018 Björn Påhlsson
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* This file is part of Mandos.
10
* Mandos is free software: you can redistribute it and/or modify it
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* 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.
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.
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/>.
23
* Contact the authors at <mandos@recompile.se>.
26
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
28
#include <stddef.h> /* size_t, NULL */
29
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
31
#include <stdbool.h> /* bool, true, false */
32
#include <stdio.h> /* fileno(), fprintf(),
33
stderr, STDOUT_FILENO, fclose() */
34
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
35
WIFEXITED(), WEXITSTATUS(), wait(),
36
pid_t, uid_t, gid_t, getuid(),
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
FD_SET(), FD_ISSET(), FD_CLR */
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG() */
42
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
43
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, write(), STDOUT_FILENO,
47
struct stat, fstat(), close(),
48
setgid(), setuid(), S_ISREG(),
49
faccessat() pipe2(), fork(),
50
_exit(), dup2(), fexecve(), read()
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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FD_CLOEXEC, openat(), scandirat(),
55
#include <string.h> /* strsep, strlen(), strsignal(),
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strcmp(), strncmp() */
57
#include <errno.h> /* errno */
58
#include <argp.h> /* struct argp_option, struct
59
argp_state, struct argp,
60
argp_parse(), ARGP_ERR_UNKNOWN,
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ARGP_KEY_END, ARGP_KEY_ARG,
63
#include <signal.h> /* struct sigaction, sigemptyset(),
64
sigaddset(), sigaction(),
65
sigprocmask(), SIG_BLOCK, SIGCHLD,
66
SIG_UNBLOCK, kill(), sig_atomic_t
68
#include <errno.h> /* errno, EBADF */
69
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
70
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
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EX_CONFIG, EX_UNAVAILABLE, EX_OK */
72
#include <errno.h> /* errno */
73
#include <error.h> /* error() */
74
#include <fnmatch.h> /* fnmatch() */
76
#define BUFFER_SIZE 256
78
#define PDIR "/lib/mandos/plugins.d"
79
#define PHDIR "/lib/mandos/plugin-helpers"
80
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
82
const char *argp_program_version = "plugin-runner " VERSION;
83
const char *argp_program_bug_address = "<mandos@recompile.se>";
85
typedef struct plugin{
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char *name; /* can be NULL or any plugin name */
93
/* Variables used for running processes*/
27
#define BUFFER_SIZE 256
100
volatile sig_atomic_t completed;
105
static plugin *plugin_list = NULL;
107
/* Gets an existing plugin based on name,
108
or if none is found, creates a new one */
109
__attribute__((warn_unused_result))
110
static plugin *getplugin(char *name){
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/* Check for existing plugin with that name */
112
for(plugin *p = plugin_list; p != NULL; p = p->next){
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or (p->name and name and (strcmp(p->name, name) == 0))){
118
/* Create a new plugin */
119
plugin *new_plugin = NULL;
121
new_plugin = malloc(sizeof(plugin));
122
} while(new_plugin == NULL and errno == EINTR);
123
if(new_plugin == NULL){
126
char *copy_name = NULL;
129
copy_name = strdup(name);
130
} while(copy_name == NULL and errno == EINTR);
131
if(copy_name == NULL){
139
*new_plugin = (plugin){ .name = copy_name,
142
.next = plugin_list };
145
new_plugin->argv = malloc(sizeof(char *) * 2);
146
} while(new_plugin->argv == NULL and errno == EINTR);
147
if(new_plugin->argv == NULL){
154
new_plugin->argv[0] = copy_name;
155
new_plugin->argv[1] = NULL;
158
new_plugin->environ = malloc(sizeof(char *));
159
} while(new_plugin->environ == NULL and errno == EINTR);
160
if(new_plugin->environ == NULL){
163
free(new_plugin->argv);
168
new_plugin->environ[0] = NULL;
170
/* Append the new plugin to the list */
171
plugin_list = new_plugin;
175
/* Helper function for add_argument and add_environment */
176
__attribute__((nonnull, warn_unused_result))
177
static bool add_to_char_array(const char *new, char ***array,
179
/* Resize the pointed-to array to hold one more pointer */
180
char **new_array = NULL;
182
new_array = realloc(*array, sizeof(char *)
183
* (size_t) ((*len) + 2));
184
} while(new_array == NULL and errno == EINTR);
186
if(new_array == NULL){
190
/* Make a copy of the new string */
194
} while(copy == NULL and errno == EINTR);
198
/* Insert the copy */
199
(*array)[*len] = copy;
201
/* Add a new terminating NULL pointer to the last element */
202
(*array)[*len] = NULL;
206
/* Add to a plugin's argument vector */
207
__attribute__((nonnull(2), warn_unused_result))
208
static bool add_argument(plugin *p, const char *arg){
212
return add_to_char_array(arg, &(p->argv), &(p->argc));
215
/* Add to a plugin's environment */
216
__attribute__((nonnull(2), warn_unused_result))
217
static bool add_environment(plugin *p, const char *def, bool replace){
221
/* namelen = length of name of environment variable */
222
size_t namelen = (size_t)(strchrnul(def, '=') - def);
223
/* Search for this environment variable */
224
for(char **envdef = p->environ; *envdef != NULL; envdef++){
225
if(strncmp(*envdef, def, namelen + 1) == 0){
226
/* It already exists */
230
new_envdef = realloc(*envdef, strlen(def) + 1);
231
} while(new_envdef == NULL and errno == EINTR);
232
if(new_envdef == NULL){
235
*envdef = new_envdef;
236
strcpy(*envdef, def);
241
return add_to_char_array(def, &(p->environ), &(p->envc));
246
* Based on the example in the GNU LibC manual chapter 13.13 "File
248
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
250
__attribute__((warn_unused_result))
251
static int set_cloexec_flag(int fd){
252
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
253
/* If reading the flags failed, return error indication now. */
257
/* Store modified flag word in the descriptor. */
258
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
261
#endif /* not O_CLOEXEC */
264
/* Mark processes as completed when they exit, and save their exit
266
static void handle_sigchld(__attribute__((unused)) int sig){
267
int old_errno = errno;
269
plugin *proc = plugin_list;
271
pid_t pid = waitpid(-1, &status, WNOHANG);
273
/* Only still running child processes */
278
/* No child processes */
281
error(0, errno, "waitpid");
284
/* A child exited, find it in process_list */
285
while(proc != NULL and proc->pid != pid){
289
/* Process not found in process list */
292
proc->status = status;
298
/* Prints out a password to stdout */
299
__attribute__((nonnull, warn_unused_result))
300
static bool print_out_password(const char *buffer, size_t length){
302
for(size_t written = 0; written < length; written += (size_t)ret){
303
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
312
/* Removes and free a plugin from the plugin list */
313
__attribute__((nonnull))
314
static void free_plugin(plugin *plugin_node){
316
for(char **arg = plugin_node->argv; *arg != NULL; arg++){
319
free(plugin_node->argv);
320
for(char **env = plugin_node->environ; *env != NULL; env++){
323
free(plugin_node->environ);
324
free(plugin_node->buffer);
326
/* Removes the plugin from the singly-linked list */
327
if(plugin_node == plugin_list){
328
/* First one - simple */
329
plugin_list = plugin_list->next;
331
/* Second one or later */
332
for(plugin *p = plugin_list; p != NULL; p = p->next){
333
if(p->next == plugin_node){
334
p->next = plugin_node->next;
343
static void free_plugin_list(void){
344
while(plugin_list != NULL){
345
free_plugin(plugin_list);
29
349
int main(int argc, char *argv[]){
30
char plugindir[] = "plugins.d";
31
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
350
char *plugindir = NULL;
351
char *pluginhelperdir = NULL;
352
char *argfile = NULL;
354
struct dirent **direntries = NULL;
36
357
int ret, maxfd = 0;
37
process *process_list = NULL;
39
dir = opendir(plugindir);
42
fprintf(stderr, "Can not open directory\n");
51
// All directory entries have been processed
56
d_name_len = strlen(dirst->d_name);
58
// Ignore dotfiles and backup files
59
if (dirst->d_name[0] == '.'
60
or dirst->d_name[d_name_len - 1] == '~'){
64
char *filename = malloc(d_name_len + plugindir_len + 2);
65
strcpy(filename, plugindir);
66
strcat(filename, "/");
67
strcat(filename, dirst->d_name);
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));
76
new_process->pid = fork();
77
if(new_process->pid == 0){
78
/* this is the child process */
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];
88
new_argv[argc] = NULL;
89
if(execv(filename, new_argv) < 0){
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){
103
new_process->buffer_size = BUFFER_SIZE;
104
new_process->buffer_length = 0;
105
FD_SET(new_process->fd, &rfds_orig);
107
if (maxfd < new_process->fd){
108
maxfd = new_process->fd;
112
new_process->next = process_list;
113
process_list = new_process;
119
if (process_list != NULL){
362
int exitstatus = EXIT_SUCCESS;
363
struct sigaction old_sigchld_action;
364
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
365
.sa_flags = SA_NOCLDSTOP };
366
char **custom_argv = NULL;
370
/* Establish a signal handler */
371
sigemptyset(&sigchld_action.sa_mask);
372
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
374
error(0, errno, "sigaddset");
375
exitstatus = EX_OSERR;
378
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
380
error(0, errno, "sigaction");
381
exitstatus = EX_OSERR;
385
/* The options we understand. */
386
struct argp_option options[] = {
387
{ .name = "global-options", .key = 'g',
388
.arg = "OPTION[,OPTION[,...]]",
389
.doc = "Options passed to all plugins" },
390
{ .name = "global-env", .key = 'G',
392
.doc = "Environment variable passed to all plugins" },
393
{ .name = "options-for", .key = 'o',
394
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
395
.doc = "Options passed only to specified plugin" },
396
{ .name = "env-for", .key = 'E',
397
.arg = "PLUGIN:ENV=value",
398
.doc = "Environment variable passed to specified plugin" },
399
{ .name = "disable", .key = 'd',
401
.doc = "Disable a specific plugin", .group = 1 },
402
{ .name = "enable", .key = 'e',
404
.doc = "Enable a specific plugin", .group = 1 },
405
{ .name = "plugin-dir", .key = 128,
407
.doc = "Specify a different plugin directory", .group = 2 },
408
{ .name = "config-file", .key = 129,
410
.doc = "Specify a different configuration file", .group = 2 },
411
{ .name = "userid", .key = 130,
412
.arg = "ID", .flags = 0,
413
.doc = "User ID the plugins will run as", .group = 3 },
414
{ .name = "groupid", .key = 131,
415
.arg = "ID", .flags = 0,
416
.doc = "Group ID the plugins will run as", .group = 3 },
417
{ .name = "debug", .key = 132,
418
.doc = "Debug mode", .group = 4 },
419
{ .name = "plugin-helper-dir", .key = 133,
421
.doc = "Specify a different plugin helper directory",
424
* These reproduce what we would get without ARGP_NO_HELP
426
{ .name = "help", .key = '?',
427
.doc = "Give this help list", .group = -1 },
428
{ .name = "usage", .key = -3,
429
.doc = "Give a short usage message", .group = -1 },
430
{ .name = "version", .key = 'V',
431
.doc = "Print program version", .group = -1 },
435
__attribute__((nonnull(3)))
436
error_t parse_opt(int key, char *arg, struct argp_state *state){
441
case 'g': /* --global-options */
444
while((plugin_option = strsep(&arg, ",")) != NULL){
445
if(not add_argument(getplugin(NULL), plugin_option)){
452
case 'G': /* --global-env */
453
if(add_environment(getplugin(NULL), arg, true)){
457
case 'o': /* --options-for */
459
char *option_list = strchr(arg, ':');
460
if(option_list == NULL){
461
argp_error(state, "No colon in \"%s\"", arg);
468
argp_error(state, "Empty plugin name");
473
while((option = strsep(&option_list, ",")) != NULL){
474
if(not add_argument(getplugin(arg), option)){
481
case 'E': /* --env-for */
483
char *envdef = strchr(arg, ':');
485
argp_error(state, "No colon in \"%s\"", arg);
492
argp_error(state, "Empty plugin name");
496
if(add_environment(getplugin(arg), envdef, true)){
501
case 'd': /* --disable */
503
plugin *p = getplugin(arg);
510
case 'e': /* --enable */
512
plugin *p = getplugin(arg);
519
case 128: /* --plugin-dir */
521
plugindir = strdup(arg);
522
if(plugindir != NULL){
526
case 129: /* --config-file */
527
/* This is already done by parse_opt_config_file() */
529
case 130: /* --userid */
530
tmp_id = strtoimax(arg, &tmp, 10);
531
if(errno != 0 or tmp == arg or *tmp != '\0'
532
or tmp_id != (uid_t)tmp_id){
533
argp_error(state, "Bad user ID number: \"%s\", using %"
534
PRIdMAX, arg, (intmax_t)uid);
540
case 131: /* --groupid */
541
tmp_id = strtoimax(arg, &tmp, 10);
542
if(errno != 0 or tmp == arg or *tmp != '\0'
543
or tmp_id != (gid_t)tmp_id){
544
argp_error(state, "Bad group ID number: \"%s\", using %"
545
PRIdMAX, arg, (intmax_t)gid);
551
case 132: /* --debug */
554
case 133: /* --plugin-helper-dir */
555
free(pluginhelperdir);
556
pluginhelperdir = strdup(arg);
557
if(pluginhelperdir != NULL){
562
* These reproduce what we would get without ARGP_NO_HELP
564
case '?': /* --help */
565
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
566
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
567
case -3: /* --usage */
568
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
569
argp_state_help(state, state->out_stream,
570
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
571
case 'V': /* --version */
572
fprintf(state->out_stream, "%s\n", argp_program_version);
576
* When adding more options before this line, remember to also add a
577
* "case" to the "parse_opt_config_file" function below.
580
/* Cryptsetup always passes an argument, which is an empty
581
string if "none" was specified in /etc/crypttab. So if
582
argument was empty, we ignore it silently. */
588
return ARGP_ERR_UNKNOWN;
590
return errno; /* Set to 0 at start */
593
/* This option parser is the same as parse_opt() above, except it
594
ignores everything but the --config-file option. */
595
error_t parse_opt_config_file(int key, char *arg,
596
__attribute__((unused))
597
struct argp_state *state){
600
case 'g': /* --global-options */
601
case 'G': /* --global-env */
602
case 'o': /* --options-for */
603
case 'E': /* --env-for */
604
case 'd': /* --disable */
605
case 'e': /* --enable */
606
case 128: /* --plugin-dir */
608
case 129: /* --config-file */
610
argfile = strdup(arg);
615
case 130: /* --userid */
616
case 131: /* --groupid */
617
case 132: /* --debug */
618
case 133: /* --plugin-helper-dir */
619
case '?': /* --help */
620
case -3: /* --usage */
621
case 'V': /* --version */
625
return ARGP_ERR_UNKNOWN;
630
struct argp argp = { .options = options,
631
.parser = parse_opt_config_file,
633
.doc = "Mandos plugin runner -- Run plugins" };
635
/* Parse using parse_opt_config_file() in order to get the custom
636
config file location, if any. */
637
ret = argp_parse(&argp, argc, argv,
638
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
646
error(0, errno, "argp_parse");
647
exitstatus = EX_OSERR;
650
exitstatus = EX_USAGE;
654
/* Reset to the normal argument parser */
655
argp.parser = parse_opt;
657
/* Open the configfile if available */
659
conffp = fopen(AFILE, "r");
661
conffp = fopen(argfile, "r");
664
char *org_line = NULL;
665
char *p, *arg, *new_arg, *line;
667
const char whitespace_delims[] = " \r\t\f\v\n";
668
const char comment_delim[] = "#";
671
custom_argv = malloc(sizeof(char*) * 2);
672
if(custom_argv == NULL){
673
error(0, errno, "malloc");
674
exitstatus = EX_OSERR;
677
custom_argv[0] = argv[0];
678
custom_argv[1] = NULL;
680
/* for each line in the config file, strip whitespace and ignore
121
fd_set rfds = rfds_orig;
122
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
123
if (select_ret == -1){
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
135
if (process_itr->buffer == NULL){
139
process_itr->buffer_size += BUFFER_SIZE;
141
ret = read(process_itr->fd, process_itr->buffer
142
+ process_itr->buffer_length, BUFFER_SIZE);
143
process_itr->buffer_length+=ret;
146
/* wait for process exit */
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);
154
FD_CLR(process_itr->fd, &rfds_orig);
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);
683
sret = getline(&org_line, &size, conffp);
689
arg = strsep(&line, comment_delim);
690
while((p = strsep(&arg, whitespace_delims)) != NULL){
696
error(0, errno, "strdup");
697
exitstatus = EX_OSERR;
704
char **new_argv = realloc(custom_argv, sizeof(char *)
705
* ((size_t)custom_argc + 1));
706
if(new_argv == NULL){
707
error(0, errno, "realloc");
708
exitstatus = EX_OSERR;
713
custom_argv = new_argv;
716
custom_argv[custom_argc-1] = new_arg;
717
custom_argv[custom_argc] = NULL;
721
ret = fclose(conffp);
722
} while(ret == EOF and errno == EINTR);
724
error(0, errno, "fclose");
725
exitstatus = EX_IOERR;
730
/* Check for harmful errors and go to fallback. Other errors might
731
not affect opening plugins */
732
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
733
error(0, errno, "fopen");
734
exitstatus = EX_OSERR;
738
/* If there were any arguments from the configuration file, pass
739
them to parser as command line arguments */
740
if(custom_argv != NULL){
741
ret = argp_parse(&argp, custom_argc, custom_argv,
742
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
750
error(0, errno, "argp_parse");
751
exitstatus = EX_OSERR;
754
exitstatus = EX_CONFIG;
759
/* Parse actual command line arguments, to let them override the
761
ret = argp_parse(&argp, argc, argv,
762
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
770
error(0, errno, "argp_parse");
771
exitstatus = EX_OSERR;
774
exitstatus = EX_USAGE;
779
char *pluginhelperenv;
781
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
782
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
784
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
786
if(ret == -1 or not bret){
787
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
788
" environment variable to \"%s\" for all plugins\n",
789
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
792
free(pluginhelperenv);
797
for(plugin *p = plugin_list; p != NULL; p = p->next){
798
fprintf(stderr, "Plugin: %s has %d arguments\n",
799
p->name ? p->name : "Global", p->argc - 1);
800
for(char **a = p->argv; *a != NULL; a++){
801
fprintf(stderr, "\tArg: %s\n", *a);
803
fprintf(stderr, "...and %d environment variables\n", p->envc);
804
for(char **a = p->environ; *a != NULL; a++){
805
fprintf(stderr, "\t%s\n", *a);
811
/* Work around Debian bug #633582:
812
<https://bugs.debian.org/633582> */
813
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
814
if(plugindir_fd == -1){
816
error(0, errno, "open(\"" PDIR "\")");
819
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
821
error(0, errno, "fstat");
823
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
824
ret = fchown(plugindir_fd, uid, gid);
826
error(0, errno, "fchown");
834
/* Lower permissions */
837
error(0, errno, "setgid");
841
error(0, errno, "setuid");
844
/* Open plugin directory with close_on_exec flag */
846
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
849
#else /* not O_CLOEXEC */
851
#endif /* not O_CLOEXEC */
854
error(0, errno, "Could not open plugin dir");
855
exitstatus = EX_UNAVAILABLE;
860
/* Set the FD_CLOEXEC flag on the directory */
861
ret = set_cloexec_flag(dir_fd);
863
error(0, errno, "set_cloexec_flag");
864
exitstatus = EX_OSERR;
867
#endif /* O_CLOEXEC */
870
int good_name(const struct dirent * const dirent){
871
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
872
"*.dpkg-old", "*.dpkg-bak",
873
"*.dpkg-divert", NULL };
875
#pragma GCC diagnostic push
876
#pragma GCC diagnostic ignored "-Wcast-qual"
878
for(const char **pat = (const char **)patterns;
879
*pat != NULL; pat++){
881
#pragma GCC diagnostic pop
883
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
886
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
887
" matching pattern %s\n", dirent->d_name, *pat);
895
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
897
if(numplugins == -1){
898
error(0, errno, "Could not scan plugin dir");
900
exitstatus = EX_OSERR;
906
/* Read and execute any executable in the plugin directory*/
907
for(int i = 0; i < numplugins; i++){
909
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
911
error(0, errno, "Could not open plugin");
915
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
917
error(0, errno, "stat");
923
/* Ignore non-executable files */
924
if(not S_ISREG(st.st_mode)
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
928
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
929
" with bad type or mode\n",
930
plugindir != NULL ? plugindir : PDIR,
931
direntries[i]->d_name);
938
plugin *p = getplugin(direntries[i]->d_name);
940
error(0, errno, "getplugin");
947
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
948
direntries[i]->d_name);
955
/* Add global arguments to argument list for this plugin */
956
plugin *g = getplugin(NULL);
958
for(char **a = g->argv + 1; *a != NULL; a++){
959
if(not add_argument(p, *a)){
960
error(0, errno, "add_argument");
963
/* Add global environment variables */
964
for(char **e = g->environ; *e != NULL; e++){
965
if(not add_environment(p, *e, false)){
966
error(0, errno, "add_environment");
971
/* If this plugin has any environment variables, we need to
972
duplicate the environment from this process, too. */
973
if(p->environ[0] != NULL){
974
for(char **e = environ; *e != NULL; e++){
975
if(not add_environment(p, *e, false)){
976
error(0, errno, "add_environment");
983
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
984
#else /* O_CLOEXEC */
985
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
986
#endif /* O_CLOEXEC */
988
error(0, errno, "pipe");
989
exitstatus = EX_OSERR;
993
if(pipefd[0] >= FD_SETSIZE){
994
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
998
exitstatus = EX_OSERR;
1003
/* Ask OS to automatic close the pipe on exec */
1004
ret = set_cloexec_flag(pipefd[0]);
1006
error(0, errno, "set_cloexec_flag");
1009
exitstatus = EX_OSERR;
1010
free(direntries[i]);
1013
ret = set_cloexec_flag(pipefd[1]);
1015
error(0, errno, "set_cloexec_flag");
1018
exitstatus = EX_OSERR;
1019
free(direntries[i]);
1022
#endif /* not O_CLOEXEC */
1023
/* Block SIGCHLD until process is safely in process list */
1024
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1025
&sigchld_action.sa_mask,
1028
error(0, errno, "sigprocmask");
1029
exitstatus = EX_OSERR;
1030
free(direntries[i]);
1033
/* Starting a new process to be watched */
1037
} while(pid == -1 and errno == EINTR);
1039
error(0, errno, "fork");
1040
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1041
&sigchld_action.sa_mask, NULL));
1044
exitstatus = EX_OSERR;
1045
free(direntries[i]);
1049
/* this is the child process */
1050
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1052
error(0, errno, "sigaction");
1055
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1057
error(0, errno, "sigprocmask");
1061
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1063
error(0, errno, "dup2");
1067
if(fexecve(plugin_fd, p->argv,
1068
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1069
error(0, errno, "fexecve for %s/%s",
1070
plugindir != NULL ? plugindir : PDIR,
1071
direntries[i]->d_name);
1076
/* Parent process */
1077
close(pipefd[1]); /* Close unused write end of pipe */
1079
plugin *new_plugin = getplugin(direntries[i]->d_name);
1080
if(new_plugin == NULL){
1081
error(0, errno, "getplugin");
1082
ret = (int)(TEMP_FAILURE_RETRY
1083
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1086
error(0, errno, "sigprocmask");
1088
exitstatus = EX_OSERR;
1089
free(direntries[i]);
1092
free(direntries[i]);
1094
new_plugin->pid = pid;
1095
new_plugin->fd = pipefd[0];
1098
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1099
new_plugin->name, (intmax_t) (new_plugin->pid));
1102
/* Unblock SIGCHLD so signal handler can be run if this process
1103
has already completed */
1104
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1105
&sigchld_action.sa_mask,
1108
error(0, errno, "sigprocmask");
1109
exitstatus = EX_OSERR;
1113
FD_SET(new_plugin->fd, &rfds_all);
1115
if(maxfd < new_plugin->fd){
1116
maxfd = new_plugin->fd;
1124
free_plugin(getplugin(NULL));
1126
for(plugin *p = plugin_list; p != NULL; p = p->next){
1130
if(p->next == NULL){
1131
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1137
/* Main loop while running plugins exist */
1139
fd_set rfds = rfds_all;
1140
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1141
if(select_ret == -1 and errno != EINTR){
1142
error(0, errno, "select");
1143
exitstatus = EX_OSERR;
1146
/* OK, now either a process completed, or something can be read
1148
for(plugin *proc = plugin_list; proc != NULL;){
1149
/* Is this process completely done? */
1150
if(proc->completed and proc->eof){
1151
/* Only accept the plugin output if it exited cleanly */
1152
if(not WIFEXITED(proc->status)
1153
or WEXITSTATUS(proc->status) != 0){
1154
/* Bad exit by plugin */
1157
if(WIFEXITED(proc->status)){
1158
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1159
" status %d\n", proc->name,
1160
(intmax_t) (proc->pid),
1161
WEXITSTATUS(proc->status));
1162
} else if(WIFSIGNALED(proc->status)){
1163
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1164
" signal %d: %s\n", proc->name,
1165
(intmax_t) (proc->pid),
1166
WTERMSIG(proc->status),
1167
strsignal(WTERMSIG(proc->status)));
1171
/* Remove the plugin */
1172
FD_CLR(proc->fd, &rfds_all);
1174
/* Block signal while modifying process_list */
1175
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1177
&sigchld_action.sa_mask,
1180
error(0, errno, "sigprocmask");
1181
exitstatus = EX_OSERR;
1185
plugin *next_plugin = proc->next;
1189
/* We are done modifying process list, so unblock signal */
1190
ret = (int)(TEMP_FAILURE_RETRY
1191
(sigprocmask(SIG_UNBLOCK,
1192
&sigchld_action.sa_mask, NULL)));
1194
error(0, errno, "sigprocmask");
1195
exitstatus = EX_OSERR;
1199
if(plugin_list == NULL){
1206
/* This process exited nicely, so print its buffer */
1208
bool bret = print_out_password(proc->buffer,
1209
proc->buffer_length);
1211
error(0, errno, "print_out_password");
1212
exitstatus = EX_IOERR;
1217
/* This process has not completed. Does it have any output? */
1218
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1219
/* This process had nothing to say at this time */
1223
/* Before reading, make the process' data buffer large enough */
1224
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1225
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1226
+ (size_t) BUFFER_SIZE);
1227
if(new_buffer == NULL){
1228
error(0, errno, "malloc");
1229
exitstatus = EX_OSERR;
1232
proc->buffer = new_buffer;
1233
proc->buffer_size += BUFFER_SIZE;
1235
/* Read from the process */
1236
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1238
+ proc->buffer_length,
1241
/* Read error from this process; ignore the error */
1249
proc->buffer_length += (size_t) sret;
1257
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1258
and exitstatus != EX_OK)){
1259
/* Fallback if all plugins failed, none are found or an error
1262
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1263
char *passwordbuffer = getpass("Password: ");
1264
size_t len = strlen(passwordbuffer);
1265
/* Strip trailing newline */
1266
if(len > 0 and passwordbuffer[len-1] == '\n'){
1267
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1270
bret = print_out_password(passwordbuffer, len);
1272
error(0, errno, "print_out_password");
1273
exitstatus = EX_IOERR;
1277
/* Restore old signal handler */
1278
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1280
error(0, errno, "sigaction");
1281
exitstatus = EX_OSERR;
1284
if(custom_argv != NULL){
1285
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1297
/* Kill the processes */
1298
for(plugin *p = plugin_list; p != NULL; p = p->next){
1301
ret = kill(p->pid, SIGTERM);
1302
if(ret == -1 and errno != ESRCH){
1303
/* Set-uid proccesses might not get closed */
1304
error(0, errno, "kill");
1309
/* Wait for any remaining child processes to terminate */
1313
if(errno != ECHILD){
1314
error(0, errno, "wait");
1320
free(pluginhelperdir);