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 © 2008-2021 Teddy Hogeborn
6
* Copyright © 2008-2021 Björn Påhlsson
8
* This file is part of Mandos.
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
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 /* strchrnul(), TEMP_FAILURE_RETRY(),
27
getline(), asprintf(), O_CLOEXEC,
28
scandirat(), pipe2() */
29
#include <argp.h> /* argp_program_version,
30
argp_program_bug_address,
32
struct argp_state, argp_error(),
33
ARGP_NO_EXIT, argp_state_help,
35
ARGP_HELP_USAGE, ARGP_HELP_EXIT_OK,
36
ARGP_KEY_ARG, ARGP_ERR_UNKNOWN,
37
struct argp, argp_parse(),
38
ARGP_IN_ORDER, ARGP_NO_HELP */
39
#include <stdbool.h> /* bool, false, true */
40
#include <sys/types.h> /* pid_t, sig_atomic_t, uid_t, gid_t,
41
getuid(), setgid(), setuid() */
42
#include <stddef.h> /* size_t, NULL */
43
#include <iso646.h> /* or, and, not */
44
#include <string.h> /* strcmp(), strdup(), strchrnul(),
45
strncmp(), strlen(), strcpy(),
46
strsep(), strchr(), strsignal() */
47
#include <stdlib.h> /* malloc(), free(), reallocarray(),
48
realloc(), EXIT_SUCCESS */
49
#include <errno.h> /* errno, EINTR, ENOMEM, ECHILD,
50
error_t, EINVAL, EMFILE, ENFILE,
52
#include <stdint.h> /* SIZE_MAX */
53
#define _GNU_SOURCE /* strchrnul(), TEMP_FAILURE_RETRY(),
54
getline(), asprintf(), O_CLOEXEC,
55
scandirat(), pipe2() */
56
#include <unistd.h> /* TEMP_FAILURE_RETRY(), ssize_t,
57
write(), STDOUT_FILENO, uid_t,
58
gid_t, getuid(), fchown(), close(),
59
symlink(), setgid(), setuid(),
60
faccessat(), X_OK, pipe(), pipe2(),
61
fork(), _exit(), dup2(), fexecve(),
63
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
64
FD_CLOEXEC, open(), O_RDONLY,
65
O_CLOEXEC, openat() */
66
#include <sys/wait.h> /* waitpid(), WNOHANG, WIFEXITED(),
67
WEXITSTATUS(), WIFSIGNALED(),
69
#include <error.h> /* error() */
70
#include <stdio.h> /* FILE, fprintf(), fopen(),
71
getline(), fclose(), EOF,
73
#include <dirent.h> /* struct dirent, scandirat(),
75
#include <sys/stat.h> /* struct stat, fstat(), S_ISDIR(),
77
#include <sys/select.h> /* fd_set, FD_ZERO(), FD_SETSIZE,
78
FD_SET(), select(), FD_CLR(),
80
#include <signal.h> /* struct sigaction, SA_NOCLDSTOP,
81
sigemptyset(), sigaddset(),
82
SIGCHLD, sigprocmask(), SIG_BLOCK,
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SIG_UNBLOCK, kill(), SIGTERM */
84
#include <sysexits.h> /* EX_OSERR, EX_USAGE, EX_IOERR,
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EX_CONFIG, EX_UNAVAILABLE, EX_OK */
86
#include <inttypes.h> /* intmax_t, strtoimax(), PRIdMAX */
87
#include <fnmatch.h> /* fnmatch(), FNM_FILE_NAME,
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FNM_PERIOD, FNM_NOMATCH */
90
#define BUFFER_SIZE 256
92
#define PDIR "/lib/mandos/plugins.d"
93
#define PHDIR "/lib/mandos/plugin-helpers"
94
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
96
const char *argp_program_version = "plugin-runner " VERSION;
97
const char *argp_program_bug_address = "<mandos@recompile.se>";
99
typedef struct plugin{
100
char *name; /* can be NULL or any plugin name */
107
/* Variables used for running processes*/
27
#define BUFFER_SIZE 256
112
size_t buffer_length;
114
volatile sig_atomic_t completed;
119
static plugin *plugin_list = NULL;
121
/* Gets an existing plugin based on name,
122
or if none is found, creates a new one */
123
__attribute__((warn_unused_result))
124
static plugin *getplugin(char *name){
125
/* Check for existing plugin with that name */
126
for(plugin *p = plugin_list; p != NULL; p = p->next){
128
or (p->name and name and (strcmp(p->name, name) == 0))){
132
/* Create a new plugin */
133
plugin *new_plugin = NULL;
135
new_plugin = malloc(sizeof(plugin));
136
} while(new_plugin == NULL and errno == EINTR);
137
if(new_plugin == NULL){
140
char *copy_name = NULL;
143
copy_name = strdup(name);
144
} while(copy_name == NULL and errno == EINTR);
145
if(copy_name == NULL){
153
*new_plugin = (plugin){ .name = copy_name,
156
.next = plugin_list };
159
new_plugin->argv = malloc(sizeof(char *) * 2);
160
} while(new_plugin->argv == NULL and errno == EINTR);
161
if(new_plugin->argv == NULL){
168
new_plugin->argv[0] = copy_name;
169
new_plugin->argv[1] = NULL;
172
new_plugin->environ = malloc(sizeof(char *));
173
} while(new_plugin->environ == NULL and errno == EINTR);
174
if(new_plugin->environ == NULL){
177
free(new_plugin->argv);
182
new_plugin->environ[0] = NULL;
184
/* Append the new plugin to the list */
185
plugin_list = new_plugin;
189
/* Helper function for add_argument and add_environment */
190
__attribute__((nonnull, warn_unused_result))
191
static bool add_to_char_array(const char *new, char ***array,
193
/* Resize the pointed-to array to hold one more pointer */
194
char **new_array = NULL;
196
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
197
new_array = reallocarray(*array, (size_t)((*len) + 2),
200
if(((size_t)((*len) + 2)) > (SIZE_MAX / sizeof(char *))){
205
new_array = realloc(*array, (size_t)((*len) + 2)
209
} while(new_array == NULL and errno == EINTR);
211
if(new_array == NULL){
215
/* Make a copy of the new string */
219
} while(copy == NULL and errno == EINTR);
223
/* Insert the copy */
224
(*array)[*len] = copy;
226
/* Add a new terminating NULL pointer to the last element */
227
(*array)[*len] = NULL;
231
/* Add to a plugin's argument vector */
232
__attribute__((nonnull(2), warn_unused_result))
233
static bool add_argument(plugin *p, const char *arg){
237
return add_to_char_array(arg, &(p->argv), &(p->argc));
240
/* Add to a plugin's environment */
241
__attribute__((nonnull(2), warn_unused_result))
242
static bool add_environment(plugin *p, const char *def, bool replace){
246
/* namelen = length of name of environment variable */
247
size_t namelen = (size_t)(strchrnul(def, '=') - def);
248
/* Search for this environment variable */
249
for(char **envdef = p->environ; *envdef != NULL; envdef++){
250
if(strncmp(*envdef, def, namelen + 1) == 0){
251
/* It already exists */
255
new_envdef = realloc(*envdef, strlen(def) + 1);
256
} while(new_envdef == NULL and errno == EINTR);
257
if(new_envdef == NULL){
260
*envdef = new_envdef;
261
strcpy(*envdef, def);
266
return add_to_char_array(def, &(p->environ), &(p->envc));
271
* Based on the example in the GNU LibC manual chapter 13.13 "File
273
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
275
__attribute__((warn_unused_result))
276
static int set_cloexec_flag(int fd){
277
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
278
/* If reading the flags failed, return error indication now. */
282
/* Store modified flag word in the descriptor. */
283
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
286
#endif /* not O_CLOEXEC */
289
/* Mark processes as completed when they exit, and save their exit
291
static void handle_sigchld(__attribute__((unused)) int sig){
292
int old_errno = errno;
294
plugin *proc = plugin_list;
296
pid_t pid = waitpid(-1, &status, WNOHANG);
298
/* Only still running child processes */
303
/* No child processes */
306
error(0, errno, "waitpid");
309
/* A child exited, find it in process_list */
310
while(proc != NULL and proc->pid != pid){
314
/* Process not found in process list */
317
proc->status = status;
323
/* Prints out a password to stdout */
324
__attribute__((nonnull, warn_unused_result))
325
static bool print_out_password(const char *buffer, size_t length){
327
for(size_t written = 0; written < length; written += (size_t)ret){
328
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
337
/* Removes and free a plugin from the plugin list */
338
__attribute__((nonnull))
339
static void free_plugin(plugin *plugin_node){
341
for(char **arg = (plugin_node->argv)+1; *arg != NULL; arg++){
344
free(plugin_node->name);
345
free(plugin_node->argv);
346
for(char **env = plugin_node->environ; *env != NULL; env++){
349
free(plugin_node->environ);
350
free(plugin_node->buffer);
352
/* Removes the plugin from the singly-linked list */
353
if(plugin_node == plugin_list){
354
/* First one - simple */
355
plugin_list = plugin_list->next;
357
/* Second one or later */
358
for(plugin *p = plugin_list; p != NULL; p = p->next){
359
if(p->next == plugin_node){
360
p->next = plugin_node->next;
369
static void free_plugin_list(void){
370
while(plugin_list != NULL){
371
free_plugin(plugin_list);
29
375
int main(int argc, char *argv[]){
30
char plugindir[] = "plugins.d";
31
size_t d_name_len, plugindir_len = sizeof(plugindir)-1;
376
char *plugindir = NULL;
377
char *pluginhelperdir = NULL;
378
char *argfile = NULL;
380
struct dirent **direntries = NULL;
36
383
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 + 1);
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){
388
int exitstatus = EXIT_SUCCESS;
389
struct sigaction old_sigchld_action;
390
struct sigaction sigchld_action = { .sa_handler = handle_sigchld,
391
.sa_flags = SA_NOCLDSTOP };
392
char **custom_argv = NULL;
396
/* Establish a signal handler */
397
sigemptyset(&sigchld_action.sa_mask);
398
ret = sigaddset(&sigchld_action.sa_mask, SIGCHLD);
400
error(0, errno, "sigaddset");
401
exitstatus = EX_OSERR;
404
ret = sigaction(SIGCHLD, &sigchld_action, &old_sigchld_action);
406
error(0, errno, "sigaction");
407
exitstatus = EX_OSERR;
411
/* The options we understand. */
412
struct argp_option options[] = {
413
{ .name = "global-options", .key = 'g',
414
.arg = "OPTION[,OPTION[,...]]",
415
.doc = "Options passed to all plugins" },
416
{ .name = "global-env", .key = 'G',
418
.doc = "Environment variable passed to all plugins" },
419
{ .name = "options-for", .key = 'o',
420
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
421
.doc = "Options passed only to specified plugin" },
422
{ .name = "env-for", .key = 'E',
423
.arg = "PLUGIN:ENV=value",
424
.doc = "Environment variable passed to specified plugin" },
425
{ .name = "disable", .key = 'd',
427
.doc = "Disable a specific plugin", .group = 1 },
428
{ .name = "enable", .key = 'e',
430
.doc = "Enable a specific plugin", .group = 1 },
431
{ .name = "plugin-dir", .key = 128,
433
.doc = "Specify a different plugin directory", .group = 2 },
434
{ .name = "config-file", .key = 129,
436
.doc = "Specify a different configuration file", .group = 2 },
437
{ .name = "userid", .key = 130,
438
.arg = "ID", .flags = 0,
439
.doc = "User ID the plugins will run as", .group = 3 },
440
{ .name = "groupid", .key = 131,
441
.arg = "ID", .flags = 0,
442
.doc = "Group ID the plugins will run as", .group = 3 },
443
{ .name = "debug", .key = 132,
444
.doc = "Debug mode", .group = 4 },
445
{ .name = "plugin-helper-dir", .key = 133,
447
.doc = "Specify a different plugin helper directory",
450
* These reproduce what we would get without ARGP_NO_HELP
452
{ .name = "help", .key = '?',
453
.doc = "Give this help list", .group = -1 },
454
{ .name = "usage", .key = -3,
455
.doc = "Give a short usage message", .group = -1 },
456
{ .name = "version", .key = 'V',
457
.doc = "Print program version", .group = -1 },
461
__attribute__((nonnull(3)))
462
error_t parse_opt(int key, char *arg, struct argp_state *state){
467
case 'g': /* --global-options */
470
while((plugin_option = strsep(&arg, ",")) != NULL){
471
if(not add_argument(getplugin(NULL), plugin_option)){
478
case 'G': /* --global-env */
479
if(add_environment(getplugin(NULL), arg, true)){
483
case 'o': /* --options-for */
485
char *option_list = strchr(arg, ':');
486
if(option_list == NULL){
487
argp_error(state, "No colon in \"%s\"", arg);
494
argp_error(state, "Empty plugin name");
499
while((option = strsep(&option_list, ",")) != NULL){
500
if(not add_argument(getplugin(arg), option)){
507
case 'E': /* --env-for */
509
char *envdef = strchr(arg, ':');
511
argp_error(state, "No colon in \"%s\"", arg);
518
argp_error(state, "Empty plugin name");
522
if(add_environment(getplugin(arg), envdef, true)){
527
case 'd': /* --disable */
529
plugin *p = getplugin(arg);
536
case 'e': /* --enable */
538
plugin *p = getplugin(arg);
545
case 128: /* --plugin-dir */
547
plugindir = strdup(arg);
548
if(plugindir != NULL){
552
case 129: /* --config-file */
553
/* This is already done by parse_opt_config_file() */
555
case 130: /* --userid */
556
tmp_id = strtoimax(arg, &tmp, 10);
557
if(errno != 0 or tmp == arg or *tmp != '\0'
558
or tmp_id != (uid_t)tmp_id){
559
argp_error(state, "Bad user ID number: \"%s\", using %"
560
PRIdMAX, arg, (intmax_t)uid);
566
case 131: /* --groupid */
567
tmp_id = strtoimax(arg, &tmp, 10);
568
if(errno != 0 or tmp == arg or *tmp != '\0'
569
or tmp_id != (gid_t)tmp_id){
570
argp_error(state, "Bad group ID number: \"%s\", using %"
571
PRIdMAX, arg, (intmax_t)gid);
577
case 132: /* --debug */
580
case 133: /* --plugin-helper-dir */
581
free(pluginhelperdir);
582
pluginhelperdir = strdup(arg);
583
if(pluginhelperdir != NULL){
588
* These reproduce what we would get without ARGP_NO_HELP
590
case '?': /* --help */
591
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
592
argp_state_help(state, state->out_stream, ARGP_HELP_STD_HELP);
593
__builtin_unreachable();
594
case -3: /* --usage */
595
state->flags &= ~(unsigned int)ARGP_NO_EXIT; /* force exit */
596
argp_state_help(state, state->out_stream,
597
ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
598
__builtin_unreachable();
599
case 'V': /* --version */
600
fprintf(state->out_stream, "%s\n", argp_program_version);
604
* When adding more options before this line, remember to also add a
605
* "case" to the "parse_opt_config_file" function below.
608
/* Cryptsetup always passes an argument, which is an empty
609
string if "none" was specified in /etc/crypttab. So if
610
argument was empty, we ignore it silently. */
615
__attribute__((fallthrough));
620
return ARGP_ERR_UNKNOWN;
622
return errno; /* Set to 0 at start */
625
/* This option parser is the same as parse_opt() above, except it
626
ignores everything but the --config-file option. */
627
error_t parse_opt_config_file(int key, char *arg,
628
__attribute__((unused))
629
struct argp_state *state){
632
case 'g': /* --global-options */
633
case 'G': /* --global-env */
634
case 'o': /* --options-for */
635
case 'E': /* --env-for */
636
case 'd': /* --disable */
637
case 'e': /* --enable */
638
case 128: /* --plugin-dir */
640
case 129: /* --config-file */
642
argfile = strdup(arg);
647
case 130: /* --userid */
648
case 131: /* --groupid */
649
case 132: /* --debug */
650
case 133: /* --plugin-helper-dir */
651
case '?': /* --help */
652
case -3: /* --usage */
653
case 'V': /* --version */
657
return ARGP_ERR_UNKNOWN;
662
struct argp argp = { .options = options,
663
.parser = parse_opt_config_file,
665
.doc = "Mandos plugin runner -- Run plugins" };
667
/* Parse using parse_opt_config_file() in order to get the custom
668
config file location, if any. */
669
ret = argp_parse(&argp, argc, argv,
670
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
678
error(0, errno, "argp_parse");
679
exitstatus = EX_OSERR;
682
exitstatus = EX_USAGE;
686
/* Reset to the normal argument parser */
687
argp.parser = parse_opt;
689
/* Open the configfile if available */
691
conffp = fopen(AFILE, "r");
693
conffp = fopen(argfile, "r");
696
char *org_line = NULL;
697
char *p, *arg, *new_arg, *line;
699
const char whitespace_delims[] = " \r\t\f\v\n";
700
const char comment_delim[] = "#";
703
custom_argv = malloc(sizeof(char*) * 2);
704
if(custom_argv == NULL){
705
error(0, errno, "malloc");
706
exitstatus = EX_OSERR;
709
custom_argv[0] = argv[0];
710
custom_argv[1] = NULL;
712
/* 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);
715
sret = getline(&org_line, &size, conffp);
721
arg = strsep(&line, comment_delim);
722
while((p = strsep(&arg, whitespace_delims)) != NULL){
728
error(0, errno, "strdup");
729
exitstatus = EX_OSERR;
736
#if defined(__GLIBC_PREREQ) and __GLIBC_PREREQ(2, 26)
737
char **new_argv = reallocarray(custom_argv, (size_t)custom_argc + 1,
740
char **new_argv = NULL;
741
if(((size_t)custom_argc + 1) > (SIZE_MAX / sizeof(char *))){
745
new_argv = realloc(custom_argv, ((size_t)custom_argc + 1)
749
if(new_argv == NULL){
750
error(0, errno, "reallocarray");
751
exitstatus = EX_OSERR;
756
custom_argv = new_argv;
759
custom_argv[custom_argc-1] = new_arg;
760
custom_argv[custom_argc] = NULL;
764
ret = fclose(conffp);
765
} while(ret == EOF and errno == EINTR);
767
error(0, errno, "fclose");
768
exitstatus = EX_IOERR;
773
/* Check for harmful errors and go to fallback. Other errors might
774
not affect opening plugins */
775
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
776
error(0, errno, "fopen");
777
exitstatus = EX_OSERR;
781
/* If there were any arguments from the configuration file, pass
782
them to parser as command line arguments */
783
if(custom_argv != NULL){
784
ret = argp_parse(&argp, custom_argc, custom_argv,
785
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
793
error(0, errno, "argp_parse");
794
exitstatus = EX_OSERR;
797
exitstatus = EX_CONFIG;
802
/* Parse actual command line arguments, to let them override the
804
ret = argp_parse(&argp, argc, argv,
805
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
813
error(0, errno, "argp_parse");
814
exitstatus = EX_OSERR;
817
exitstatus = EX_USAGE;
822
char *pluginhelperenv;
824
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
825
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
827
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
829
if(ret == -1 or not bret){
830
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
831
" environment variable to \"%s\" for all plugins\n",
832
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
835
free(pluginhelperenv);
840
for(plugin *p = plugin_list; p != NULL; p = p->next){
841
fprintf(stderr, "Plugin: %s has %d arguments\n",
842
p->name ? p->name : "Global", p->argc - 1);
843
for(char **a = p->argv; *a != NULL; a++){
844
fprintf(stderr, "\tArg: %s\n", *a);
846
fprintf(stderr, "...and %d environment variables\n", p->envc);
847
for(char **a = p->environ; *a != NULL; a++){
848
fprintf(stderr, "\t%s\n", *a);
854
/* Work around Debian bug #633582:
855
<https://bugs.debian.org/633582> */
856
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
857
if(plugindir_fd == -1){
859
error(0, errno, "open(\"" PDIR "\")");
862
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
864
error(0, errno, "fstat");
866
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
867
ret = fchown(plugindir_fd, uid, gid);
869
error(0, errno, "fchown");
876
/* Work around Debian bug #981302
877
<https://bugs.debian.org/981302> */
878
if(lstat("/dev/fd", &st) != 0 and errno == ENOENT){
879
ret = symlink("/proc/self/fd", "/dev/fd");
881
error(0, errno, "Failed to create /dev/fd symlink");
886
/* Lower permissions */
889
error(0, errno, "setgid");
893
error(0, errno, "setuid");
896
/* Open plugin directory with close_on_exec flag */
898
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
901
#else /* not O_CLOEXEC */
903
#endif /* not O_CLOEXEC */
906
error(0, errno, "Could not open plugin dir");
907
exitstatus = EX_UNAVAILABLE;
912
/* Set the FD_CLOEXEC flag on the directory */
913
ret = set_cloexec_flag(dir_fd);
915
error(0, errno, "set_cloexec_flag");
916
exitstatus = EX_OSERR;
919
#endif /* O_CLOEXEC */
922
int good_name(const struct dirent * const dirent){
923
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
924
"*.dpkg-old", "*.dpkg-bak",
925
"*.dpkg-divert", NULL };
927
#pragma GCC diagnostic push
928
#pragma GCC diagnostic ignored "-Wcast-qual"
930
for(const char **pat = (const char **)patterns;
931
*pat != NULL; pat++){
933
#pragma GCC diagnostic pop
935
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
938
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
939
" matching pattern %s\n", dirent->d_name, *pat);
947
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
949
if(numplugins == -1){
950
error(0, errno, "Could not scan plugin dir");
952
exitstatus = EX_OSERR;
958
/* Read and execute any executable in the plugin directory*/
959
for(int i = 0; i < numplugins; i++){
961
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
963
error(0, errno, "Could not open plugin");
967
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
969
error(0, errno, "stat");
975
/* Ignore non-executable files */
976
if(not S_ISREG(st.st_mode)
977
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
980
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
981
" with bad type or mode\n",
982
plugindir != NULL ? plugindir : PDIR,
983
direntries[i]->d_name);
990
plugin *p = getplugin(direntries[i]->d_name);
992
error(0, errno, "getplugin");
999
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
1000
direntries[i]->d_name);
1003
free(direntries[i]);
1007
/* Add global arguments to argument list for this plugin */
1008
plugin *g = getplugin(NULL);
1010
for(char **a = g->argv + 1; *a != NULL; a++){
1011
if(not add_argument(p, *a)){
1012
error(0, errno, "add_argument");
1015
/* Add global environment variables */
1016
for(char **e = g->environ; *e != NULL; e++){
1017
if(not add_environment(p, *e, false)){
1018
error(0, errno, "add_environment");
1023
/* If this plugin has any environment variables, we need to
1024
duplicate the environment from this process, too. */
1025
if(p->environ[0] != NULL){
1026
for(char **e = environ; *e != NULL; e++){
1027
if(not add_environment(p, *e, false)){
1028
error(0, errno, "add_environment");
1035
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
1036
#else /* O_CLOEXEC */
1037
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
1038
#endif /* O_CLOEXEC */
1040
error(0, errno, "pipe");
1041
exitstatus = EX_OSERR;
1042
free(direntries[i]);
1045
if(pipefd[0] >= FD_SETSIZE){
1046
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1050
exitstatus = EX_OSERR;
1051
free(direntries[i]);
1055
/* Ask OS to automatic close the pipe on exec */
1056
ret = set_cloexec_flag(pipefd[0]);
1058
error(0, errno, "set_cloexec_flag");
1061
exitstatus = EX_OSERR;
1062
free(direntries[i]);
1065
ret = set_cloexec_flag(pipefd[1]);
1067
error(0, errno, "set_cloexec_flag");
1070
exitstatus = EX_OSERR;
1071
free(direntries[i]);
1074
#endif /* not O_CLOEXEC */
1075
/* Block SIGCHLD until process is safely in process list */
1076
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1077
&sigchld_action.sa_mask,
1080
error(0, errno, "sigprocmask");
1081
exitstatus = EX_OSERR;
1082
free(direntries[i]);
1085
/* Starting a new process to be watched */
1089
} while(pid == -1 and errno == EINTR);
1091
error(0, errno, "fork");
1092
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1093
&sigchld_action.sa_mask, NULL));
1096
exitstatus = EX_OSERR;
1097
free(direntries[i]);
1101
/* this is the child process */
1102
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1104
error(0, errno, "sigaction");
1107
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1109
error(0, errno, "sigprocmask");
1113
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1115
error(0, errno, "dup2");
1119
if(fexecve(plugin_fd, p->argv,
1120
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1121
error(0, errno, "fexecve for %s/%s",
1122
plugindir != NULL ? plugindir : PDIR,
1123
direntries[i]->d_name);
1128
/* Parent process */
1129
close(pipefd[1]); /* Close unused write end of pipe */
1131
plugin *new_plugin = getplugin(direntries[i]->d_name);
1132
if(new_plugin == NULL){
1133
error(0, errno, "getplugin");
1134
ret = (int)(TEMP_FAILURE_RETRY
1135
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1138
error(0, errno, "sigprocmask");
1140
exitstatus = EX_OSERR;
1141
free(direntries[i]);
1144
free(direntries[i]);
1146
new_plugin->pid = pid;
1147
new_plugin->fd = pipefd[0];
1150
fprintf(stderr, "Plugin %s started (PID %" PRIdMAX ")\n",
1151
new_plugin->name, (intmax_t) (new_plugin->pid));
1154
/* Unblock SIGCHLD so signal handler can be run if this process
1155
has already completed */
1156
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1157
&sigchld_action.sa_mask,
1160
error(0, errno, "sigprocmask");
1161
exitstatus = EX_OSERR;
1165
FD_SET(new_plugin->fd, &rfds_all);
1167
if(maxfd < new_plugin->fd){
1168
maxfd = new_plugin->fd;
1176
free_plugin(getplugin(NULL));
1178
for(plugin *p = plugin_list; p != NULL; p = p->next){
1182
if(p->next == NULL){
1183
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1189
/* Main loop while running plugins exist */
1191
fd_set rfds = rfds_all;
1192
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1193
if(select_ret == -1 and errno != EINTR){
1194
error(0, errno, "select");
1195
exitstatus = EX_OSERR;
1198
/* OK, now either a process completed, or something can be read
1200
for(plugin *proc = plugin_list; proc != NULL;){
1201
/* Is this process completely done? */
1202
if(proc->completed and proc->eof){
1203
/* Only accept the plugin output if it exited cleanly */
1204
if(not WIFEXITED(proc->status)
1205
or WEXITSTATUS(proc->status) != 0){
1206
/* Bad exit by plugin */
1209
if(WIFEXITED(proc->status)){
1210
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1211
" status %d\n", proc->name,
1212
(intmax_t) (proc->pid),
1213
WEXITSTATUS(proc->status));
1214
} else if(WIFSIGNALED(proc->status)){
1215
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1216
" signal %d: %s\n", proc->name,
1217
(intmax_t) (proc->pid),
1218
WTERMSIG(proc->status),
1219
strsignal(WTERMSIG(proc->status)));
1223
/* Remove the plugin */
1224
FD_CLR(proc->fd, &rfds_all);
1226
/* Block signal while modifying process_list */
1227
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1229
&sigchld_action.sa_mask,
1232
error(0, errno, "sigprocmask");
1233
exitstatus = EX_OSERR;
1237
plugin *next_plugin = proc->next;
1241
/* We are done modifying process list, so unblock signal */
1242
ret = (int)(TEMP_FAILURE_RETRY
1243
(sigprocmask(SIG_UNBLOCK,
1244
&sigchld_action.sa_mask, NULL)));
1246
error(0, errno, "sigprocmask");
1247
exitstatus = EX_OSERR;
1251
if(plugin_list == NULL){
1258
/* This process exited nicely, so print its buffer */
1260
bool bret = print_out_password(proc->buffer,
1261
proc->buffer_length);
1263
error(0, errno, "print_out_password");
1264
exitstatus = EX_IOERR;
1269
/* This process has not completed. Does it have any output? */
1270
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1271
/* This process had nothing to say at this time */
1275
/* Before reading, make the process' data buffer large enough */
1276
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1277
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1278
+ (size_t) BUFFER_SIZE);
1279
if(new_buffer == NULL){
1280
error(0, errno, "malloc");
1281
exitstatus = EX_OSERR;
1284
proc->buffer = new_buffer;
1285
proc->buffer_size += BUFFER_SIZE;
1287
/* Read from the process */
1288
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1290
+ proc->buffer_length,
1293
/* Read error from this process; ignore the error */
1301
proc->buffer_length += (size_t) sret;
1309
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1310
and exitstatus != EX_OK)){
1311
/* Fallback if all plugins failed, none are found or an error
1314
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1315
char *passwordbuffer = getpass("Password: ");
1316
size_t len = strlen(passwordbuffer);
1317
/* Strip trailing newline */
1318
if(len > 0 and passwordbuffer[len-1] == '\n'){
1319
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1322
bret = print_out_password(passwordbuffer, len);
1324
error(0, errno, "print_out_password");
1325
exitstatus = EX_IOERR;
1329
/* Restore old signal handler */
1330
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1332
error(0, errno, "sigaction");
1333
exitstatus = EX_OSERR;
1336
if(custom_argv != NULL){
1337
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1349
/* Kill the processes */
1350
for(plugin *p = plugin_list; p != NULL; p = p->next){
1353
ret = kill(p->pid, SIGTERM);
1354
if(ret == -1 and errno != ESRCH){
1355
/* Set-uid proccesses might not get closed */
1356
error(0, errno, "kill");
1361
/* Wait for any remaining child processes to terminate */
1365
if(errno != ECHILD){
1366
error(0, errno, "wait");
1372
free(pluginhelperdir);