18
19
* along with this program. If not, see
19
20
* <http://www.gnu.org/licenses/>.
21
* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
22
* <https://www.fukt.bsnet.se/~teddy/>.
22
* Contact the authors at <mandos@recompile.se>.
25
#define _FORTIFY_SOURCE 2
27
#include <stdio.h> /* popen, fileno */
28
#include <iso646.h> /* and, or, not */
29
#include <sys/types.h> /* DIR, opendir, stat, struct stat, waitpid,
30
WIFEXITED, WEXITSTATUS, wait */
31
#include <sys/wait.h> /* wait */
32
#include <dirent.h> /* DIR, opendir */
33
#include <sys/stat.h> /* stat, struct stat */
34
#include <unistd.h> /* stat, struct stat, chdir */
35
#include <stdlib.h> /* EXIT_FAILURE */
36
#include <sys/select.h> /* fd_set, select, FD_ZERO, FD_SET,
38
#include <string.h> /* strlen, strcpy, strcat */
39
#include <stdbool.h> /* true */
40
#include <sys/wait.h> /* waitpid, WIFEXITED, WEXITSTATUS */
41
#include <errno.h> /* errno */
42
#include <argp.h> /* argp */
46
typedef struct process{
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
27
#include <stddef.h> /* size_t, NULL */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
30
#include <stdbool.h> /* bool, true, false */
31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO, fclose() */
33
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
34
WIFEXITED(), WEXITSTATUS(), wait(),
35
pid_t, uid_t, gid_t, getuid(),
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(), 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,
46
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,
53
FD_CLOEXEC, openat(), scandirat(),
55
#include <string.h> /* strsep, strlen(), strsignal(),
56
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,
61
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,
71
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{
86
char *name; /* can be NULL or any plugin name */
93
/* Variables used for running processes*/
50
97
size_t buffer_size;
51
98
size_t buffer_length;
55
typedef struct plugin{
56
char *name; /* can be "global" and any plugin name */
100
volatile sig_atomic_t completed;
60
102
struct plugin *next;
63
plugin *getplugin(char *name, plugin **plugin_list){
64
for (plugin *p = *plugin_list; p != NULL; p = p->next){
66
or (p->name and name and (strcmp(p->name, name) == 0))){
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){
111
/* Check for existing plugin with that name */
112
for(plugin *p = plugin_list; p != NULL; p = p->next){
114
or (p->name and name and (strcmp(p->name, name) == 0))){
70
118
/* Create a new plugin */
71
plugin *new_plugin = malloc(sizeof(plugin));
72
if (new_plugin == NULL){
76
new_plugin->name = name;
77
new_plugin->argv = malloc(sizeof(char *) * 2);
78
if (new_plugin->argv == NULL){
82
new_plugin->argv[0] = name;
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;
83
155
new_plugin->argv[1] = NULL;
85
new_plugin->disable = false;
86
new_plugin->next = *plugin_list;
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;
87
170
/* Append the new plugin to the list */
88
*plugin_list = new_plugin;
171
plugin_list = new_plugin;
89
172
return new_plugin;
92
void addarguments(plugin *p, char *arg){
93
p->argv[p->argc] = arg;
94
p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
100
p->argv[p->argc] = NULL;
103
#define BUFFER_SIZE 256
105
const char *argp_program_version =
106
"plugbasedclient 0.9";
107
const char *argp_program_bug_address =
108
"<mandos@fukt.bsnet.se>";
110
"Mandos plugin runner -- Run Mandos plugins";
111
/* A description of the arguments we accept. */
112
static char args_doc[] = "";
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);
114
349
int main(int argc, char *argv[]){
115
const char *plugindir = "plugins.d";
118
struct dirent *dirst;
350
char *plugindir = NULL;
351
char *pluginhelperdir = NULL;
352
char *argfile = NULL;
354
struct dirent **direntries = NULL;
121
357
int ret, maxfd = 0;
122
process *process_list = NULL;
123
359
uid_t uid = 65534;
124
360
gid_t gid = 65534;
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;
125
385
/* The options we understand. */
126
386
struct argp_option options[] = {
127
387
{ .name = "global-options", .key = 'g',
128
.arg = "option[,option[,...]]", .flags = 0,
129
.doc = "Options effecting all plugins" },
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" },
130
393
{ .name = "options-for", .key = 'o',
131
.arg = "plugin:option[,option[,...]]", .flags = 0,
132
.doc = "Options effecting only specified plugins" },
133
{ .name = "disable-plugin", .key = 'd',
134
.arg = "Plugin[,Plugin[,...]]", .flags = 0,
135
.doc = "Option to disable specififed plugins" },
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 },
136
405
{ .name = "plugin-dir", .key = 128,
137
.arg = "Directory", .flags = 0,
138
.doc = "Option to change directory to search for plugins" },
139
{ .name = "userid", .key = 129,
140
.arg = "Id", .flags = 0,
141
.doc = "Option to change which user id the plugins will run as" },
142
{ .name = "groupid", .key = 130,
143
.arg = "Id", .flags = 0,
144
.doc = "Option to change which group id the plugins will run as" },
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 },
148
error_t parse_opt (int key, char *arg, struct argp_state *state) {
149
/* Get the INPUT argument from `argp_parse', which we
150
know is a pointer to our arguments structure. */
151
plugin **plugins = state->input;
155
char *p = strtok(arg, ",");
157
addarguments(getplugin(NULL, plugins), p);
158
p = strtok(NULL, ",");
164
char *name = strtok(arg, ":");
165
char *p = strtok(NULL, ":");
168
addarguments(getplugin(name, plugins), p);
169
p = strtok(NULL, ",");
175
char *p = strtok(arg, ",");
177
getplugin(p, plugins)->disable = true;
178
p = strtok(NULL, ",");
186
uid = (uid_t)strtol(arg, NULL, 10);
189
gid = (gid_t)strtol(arg, NULL, 10);
197
return ARGP_ERR_UNKNOWN;
202
plugin *plugin_list = NULL;
204
struct argp argp = { .options = options, .parser = parse_opt,
205
.args_doc = args_doc, .doc = doc };
207
argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
209
/* for(plugin *p = plugin_list; p != NULL; p=p->next){ */
210
/* fprintf(stderr, "Plugin: %s has %d arguments\n", p->name ? p->name : "Global", p->argc); */
211
/* for(char **a = p->argv + 1; *a != NULL; a++){ */
212
/* fprintf(stderr, "\tArg: %s\n", *a); */
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. */
587
return ARGP_ERR_UNKNOWN;
589
return errno; /* Set to 0 at start */
592
/* This option parser is the same as parse_opt() above, except it
593
ignores everything but the --config-file option. */
594
error_t parse_opt_config_file(int key, char *arg,
595
__attribute__((unused))
596
struct argp_state *state){
599
case 'g': /* --global-options */
600
case 'G': /* --global-env */
601
case 'o': /* --options-for */
602
case 'E': /* --env-for */
603
case 'd': /* --disable */
604
case 'e': /* --enable */
605
case 128: /* --plugin-dir */
607
case 129: /* --config-file */
609
argfile = strdup(arg);
614
case 130: /* --userid */
615
case 131: /* --groupid */
616
case 132: /* --debug */
617
case 133: /* --plugin-helper-dir */
618
case '?': /* --help */
619
case -3: /* --usage */
620
case 'V': /* --version */
624
return ARGP_ERR_UNKNOWN;
629
struct argp argp = { .options = options,
630
.parser = parse_opt_config_file,
632
.doc = "Mandos plugin runner -- Run plugins" };
634
/* Parse using parse_opt_config_file() in order to get the custom
635
config file location, if any. */
636
ret = argp_parse(&argp, argc, argv,
637
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
645
error(0, errno, "argp_parse");
646
exitstatus = EX_OSERR;
649
exitstatus = EX_USAGE;
653
/* Reset to the normal argument parser */
654
argp.parser = parse_opt;
656
/* Open the configfile if available */
658
conffp = fopen(AFILE, "r");
660
conffp = fopen(argfile, "r");
663
char *org_line = NULL;
664
char *p, *arg, *new_arg, *line;
666
const char whitespace_delims[] = " \r\t\f\v\n";
667
const char comment_delim[] = "#";
670
custom_argv = malloc(sizeof(char*) * 2);
671
if(custom_argv == NULL){
672
error(0, errno, "malloc");
673
exitstatus = EX_OSERR;
676
custom_argv[0] = argv[0];
677
custom_argv[1] = NULL;
679
/* for each line in the config file, strip whitespace and ignore
682
sret = getline(&org_line, &size, conffp);
688
arg = strsep(&line, comment_delim);
689
while((p = strsep(&arg, whitespace_delims)) != NULL){
695
error(0, errno, "strdup");
696
exitstatus = EX_OSERR;
703
char **new_argv = realloc(custom_argv, sizeof(char *)
704
* ((size_t)custom_argc + 1));
705
if(new_argv == NULL){
706
error(0, errno, "realloc");
707
exitstatus = EX_OSERR;
712
custom_argv = new_argv;
715
custom_argv[custom_argc-1] = new_arg;
716
custom_argv[custom_argc] = NULL;
720
ret = fclose(conffp);
721
} while(ret == EOF and errno == EINTR);
723
error(0, errno, "fclose");
724
exitstatus = EX_IOERR;
729
/* Check for harmful errors and go to fallback. Other errors might
730
not affect opening plugins */
731
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
732
error(0, errno, "fopen");
733
exitstatus = EX_OSERR;
737
/* If there were any arguments from the configuration file, pass
738
them to parser as command line arguments */
739
if(custom_argv != NULL){
740
ret = argp_parse(&argp, custom_argc, custom_argv,
741
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
749
error(0, errno, "argp_parse");
750
exitstatus = EX_OSERR;
753
exitstatus = EX_CONFIG;
758
/* Parse actual command line arguments, to let them override the
760
ret = argp_parse(&argp, argc, argv,
761
ARGP_IN_ORDER | ARGP_NO_EXIT | ARGP_NO_HELP,
769
error(0, errno, "argp_parse");
770
exitstatus = EX_OSERR;
773
exitstatus = EX_USAGE;
778
char *pluginhelperenv;
780
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
781
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
783
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
785
if(ret == -1 or not bret){
786
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
787
" environment variable to \"%s\" for all plugins\n",
788
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
791
free(pluginhelperenv);
796
for(plugin *p = plugin_list; p != NULL; p=p->next){
797
fprintf(stderr, "Plugin: %s has %d arguments\n",
798
p->name ? p->name : "Global", p->argc - 1);
799
for(char **a = p->argv; *a != NULL; a++){
800
fprintf(stderr, "\tArg: %s\n", *a);
802
fprintf(stderr, "...and %d environment variables\n", p->envc);
803
for(char **a = p->environ; *a != NULL; a++){
804
fprintf(stderr, "\t%s\n", *a);
810
/* Work around Debian bug #633582:
811
<http://bugs.debian.org/633582> */
812
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
813
if(plugindir_fd == -1){
815
error(0, errno, "open(\"" PDIR "\")");
818
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
820
error(0, errno, "fstat");
822
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
823
ret = fchown(plugindir_fd, uid, gid);
825
error(0, errno, "fchown");
833
/* Lower permissions */
836
error(0, errno, "setgid");
218
838
ret = setuid(uid);
228
dir = opendir(plugindir);
231
fprintf(stderr, "Can not open directory\n");
238
dirst = readdir(dir);
240
// All directory entries have been processed
245
d_name_len = strlen(dirst->d_name);
247
// Ignore dotfiles and backup files
248
if (dirst->d_name[0] == '.'
249
or dirst->d_name[d_name_len - 1] == '~'){
253
char *filename = malloc(d_name_len + strlen(plugindir) + 2);
254
strcpy(filename, plugindir);
255
strcat(filename, "/");
256
strcat(filename, dirst->d_name);
260
if (S_ISREG(st.st_mode)
261
and (access(filename, X_OK) == 0)
262
and not (getplugin(dirst->d_name, &plugin_list)->disable)){
263
// Starting a new process to be watched
264
process *new_process = malloc(sizeof(process));
271
new_process->pid = fork();
272
if(new_process->pid == 0){
273
/* this is the child process */
275
close(pipefd[0]); /* close unused read end of pipe */
276
dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
278
plugin *p = getplugin(dirst->d_name, &plugin_list);
279
plugin *g = getplugin(NULL, &plugin_list);
840
error(0, errno, "setuid");
843
/* Open plugin directory with close_on_exec flag */
845
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
848
#else /* not O_CLOEXEC */
850
#endif /* not O_CLOEXEC */
853
error(0, errno, "Could not open plugin dir");
854
exitstatus = EX_UNAVAILABLE;
859
/* Set the FD_CLOEXEC flag on the directory */
860
ret = set_cloexec_flag(dir_fd);
862
error(0, errno, "set_cloexec_flag");
863
exitstatus = EX_OSERR;
866
#endif /* O_CLOEXEC */
869
int good_name(const struct dirent * const dirent){
870
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
871
"*.dpkg-old", "*.dpkg-bak",
872
"*.dpkg-divert", NULL };
874
#pragma GCC diagnostic push
875
#pragma GCC diagnostic ignored "-Wcast-qual"
877
for(const char **pat = (const char **)patterns;
878
*pat != NULL; pat++){
880
#pragma GCC diagnostic pop
882
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
885
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
886
" matching pattern %s\n", dirent->d_name, *pat);
895
#if __GLIBC_PREREQ(2, 15)
896
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
898
#else /* not __GLIBC_PREREQ(2, 15) */
899
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
900
&direntries, good_name, alphasort);
901
#endif /* not __GLIBC_PREREQ(2, 15) */
902
#else /* not __GLIBC__ */
903
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
904
&direntries, good_name, alphasort);
905
#endif /* not __GLIBC__ */
906
if(numplugins == -1){
907
error(0, errno, "Could not scan plugin dir");
909
exitstatus = EX_OSERR;
915
/* Read and execute any executable in the plugin directory*/
916
for(int i = 0; i < numplugins; i++){
918
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
920
error(0, errno, "Could not open plugin");
924
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
926
error(0, errno, "stat");
932
/* Ignore non-executable files */
933
if(not S_ISREG(st.st_mode)
934
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
937
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
938
" with bad type or mode\n",
939
plugindir != NULL ? plugindir : PDIR,
940
direntries[i]->d_name);
947
plugin *p = getplugin(direntries[i]->d_name);
949
error(0, errno, "getplugin");
956
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
957
direntries[i]->d_name);
964
/* Add global arguments to argument list for this plugin */
965
plugin *g = getplugin(NULL);
280
967
for(char **a = g->argv + 1; *a != NULL; a++){
283
if(execv(filename, p->argv) < 0){
290
close(pipefd[1]); /* close unused write end of pipe */
291
new_process->fd = pipefd[0];
292
new_process->buffer = malloc(BUFFER_SIZE);
293
if (new_process->buffer == NULL){
297
new_process->buffer_size = BUFFER_SIZE;
298
new_process->buffer_length = 0;
299
FD_SET(new_process->fd, &rfds_orig);
301
if (maxfd < new_process->fd){
302
maxfd = new_process->fd;
306
new_process->next = process_list;
307
process_list = new_process;
313
if (process_list != NULL){
315
fd_set rfds = rfds_orig;
316
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
317
if (select_ret == -1){
321
for(process *process_itr = process_list; process_itr != NULL;
322
process_itr = process_itr->next){
323
if(FD_ISSET(process_itr->fd, &rfds)){
324
if(process_itr->buffer_length + BUFFER_SIZE
325
> process_itr->buffer_size){
326
process_itr->buffer = realloc(process_itr->buffer,
327
process_itr->buffer_size
328
+ (size_t) BUFFER_SIZE);
329
if (process_itr->buffer == NULL){
333
process_itr->buffer_size += BUFFER_SIZE;
335
ret = read(process_itr->fd, process_itr->buffer
336
+ process_itr->buffer_length, BUFFER_SIZE);
338
/* Read error from this process; ignore it */
341
process_itr->buffer_length += (size_t) ret;
344
/* wait for process exit */
346
waitpid(process_itr->pid, &status, 0);
347
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
348
for(size_t written = 0;
349
written < process_itr->buffer_length;){
350
ret = write(STDOUT_FILENO,
351
process_itr->buffer + written,
352
process_itr->buffer_length - written);
357
written += (size_t)ret;
361
FD_CLR(process_itr->fd, &rfds_orig);
371
for(process *process_itr = process_list; process_itr != NULL;
372
process_itr = process_itr->next){
373
close(process_itr->fd);
374
kill(process_itr->pid, SIGTERM);
375
free(process_itr->buffer);
968
if(not add_argument(p, *a)){
969
error(0, errno, "add_argument");
972
/* Add global environment variables */
973
for(char **e = g->environ; *e != NULL; e++){
974
if(not add_environment(p, *e, false)){
975
error(0, errno, "add_environment");
980
/* If this plugin has any environment variables, we need to
981
duplicate the environment from this process, too. */
982
if(p->environ[0] != NULL){
983
for(char **e = environ; *e != NULL; e++){
984
if(not add_environment(p, *e, false)){
985
error(0, errno, "add_environment");
992
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
993
#else /* O_CLOEXEC */
994
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
995
#endif /* O_CLOEXEC */
997
error(0, errno, "pipe");
998
exitstatus = EX_OSERR;
1002
if(pipefd[0] >= FD_SETSIZE){
1003
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1007
exitstatus = EX_OSERR;
1008
free(direntries[i]);
1012
/* Ask OS to automatic close the pipe on exec */
1013
ret = set_cloexec_flag(pipefd[0]);
1015
error(0, errno, "set_cloexec_flag");
1018
exitstatus = EX_OSERR;
1019
free(direntries[i]);
1022
ret = set_cloexec_flag(pipefd[1]);
1024
error(0, errno, "set_cloexec_flag");
1027
exitstatus = EX_OSERR;
1028
free(direntries[i]);
1031
#endif /* not O_CLOEXEC */
1032
/* Block SIGCHLD until process is safely in process list */
1033
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1034
&sigchld_action.sa_mask,
1037
error(0, errno, "sigprocmask");
1038
exitstatus = EX_OSERR;
1039
free(direntries[i]);
1042
/* Starting a new process to be watched */
1046
} while(pid == -1 and errno == EINTR);
1048
error(0, errno, "fork");
1049
TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1050
&sigchld_action.sa_mask, NULL));
1053
exitstatus = EX_OSERR;
1054
free(direntries[i]);
1058
/* this is the child process */
1059
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1061
error(0, errno, "sigaction");
1064
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
1066
error(0, errno, "sigprocmask");
1070
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
1072
error(0, errno, "dup2");
1076
if(fexecve(plugin_fd, p->argv,
1077
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1078
error(0, errno, "fexecve for %s/%s",
1079
plugindir != NULL ? plugindir : PDIR,
1080
direntries[i]->d_name);
1085
/* Parent process */
1086
close(pipefd[1]); /* Close unused write end of pipe */
1088
plugin *new_plugin = getplugin(direntries[i]->d_name);
1089
if(new_plugin == NULL){
1090
error(0, errno, "getplugin");
1091
ret = (int)(TEMP_FAILURE_RETRY
1092
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1095
error(0, errno, "sigprocmask");
1097
exitstatus = EX_OSERR;
1098
free(direntries[i]);
1101
free(direntries[i]);
1103
new_plugin->pid = pid;
1104
new_plugin->fd = pipefd[0];
1106
/* Unblock SIGCHLD so signal handler can be run if this process
1107
has already completed */
1108
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1109
&sigchld_action.sa_mask,
1112
error(0, errno, "sigprocmask");
1113
exitstatus = EX_OSERR;
1117
#if defined (__GNUC__) and defined (__GLIBC__)
1118
#if not __GLIBC_PREREQ(2, 16)
1119
#pragma GCC diagnostic push
1120
#pragma GCC diagnostic ignored "-Wsign-conversion"
1123
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
1124
-Wconversion in GNU libc
1126
#if defined (__GNUC__) and defined (__GLIBC__)
1127
#if not __GLIBC_PREREQ(2, 16)
1128
#pragma GCC diagnostic pop
1132
if(maxfd < new_plugin->fd){
1133
maxfd = new_plugin->fd;
1141
free_plugin(getplugin(NULL));
1143
for(plugin *p = plugin_list; p != NULL; p = p->next){
1147
if(p->next == NULL){
1148
fprintf(stderr, "No plugin processes started. Incorrect plugin"
1154
/* Main loop while running plugins exist */
1156
fd_set rfds = rfds_all;
1157
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
1158
if(select_ret == -1 and errno != EINTR){
1159
error(0, errno, "select");
1160
exitstatus = EX_OSERR;
1163
/* OK, now either a process completed, or something can be read
1165
for(plugin *proc = plugin_list; proc != NULL;){
1166
/* Is this process completely done? */
1167
if(proc->completed and proc->eof){
1168
/* Only accept the plugin output if it exited cleanly */
1169
if(not WIFEXITED(proc->status)
1170
or WEXITSTATUS(proc->status) != 0){
1171
/* Bad exit by plugin */
1174
if(WIFEXITED(proc->status)){
1175
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1176
" status %d\n", proc->name,
1177
(intmax_t) (proc->pid),
1178
WEXITSTATUS(proc->status));
1179
} else if(WIFSIGNALED(proc->status)){
1180
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1181
" signal %d: %s\n", proc->name,
1182
(intmax_t) (proc->pid),
1183
WTERMSIG(proc->status),
1184
strsignal(WTERMSIG(proc->status)));
1185
} else if(WCOREDUMP(proc->status)){
1186
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1187
" core\n", proc->name, (intmax_t) (proc->pid));
1191
/* Remove the plugin */
1192
#if defined (__GNUC__) and defined (__GLIBC__)
1193
#if not __GLIBC_PREREQ(2, 16)
1194
#pragma GCC diagnostic push
1195
#pragma GCC diagnostic ignored "-Wsign-conversion"
1198
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1199
-Wconversion in GNU libc
1201
#if defined (__GNUC__) and defined (__GLIBC__)
1202
#if not __GLIBC_PREREQ(2, 16)
1203
#pragma GCC diagnostic pop
1207
/* Block signal while modifying process_list */
1208
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1210
&sigchld_action.sa_mask,
1213
error(0, errno, "sigprocmask");
1214
exitstatus = EX_OSERR;
1218
plugin *next_plugin = proc->next;
1222
/* We are done modifying process list, so unblock signal */
1223
ret = (int)(TEMP_FAILURE_RETRY
1224
(sigprocmask(SIG_UNBLOCK,
1225
&sigchld_action.sa_mask, NULL)));
1227
error(0, errno, "sigprocmask");
1228
exitstatus = EX_OSERR;
1232
if(plugin_list == NULL){
1239
/* This process exited nicely, so print its buffer */
1241
bool bret = print_out_password(proc->buffer,
1242
proc->buffer_length);
1244
error(0, errno, "print_out_password");
1245
exitstatus = EX_IOERR;
1250
/* This process has not completed. Does it have any output? */
1251
#if defined (__GNUC__) and defined (__GLIBC__)
1252
#if not __GLIBC_PREREQ(2, 16)
1253
#pragma GCC diagnostic push
1254
#pragma GCC diagnostic ignored "-Wsign-conversion"
1257
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1263
#if defined (__GNUC__) and defined (__GLIBC__)
1264
#if not __GLIBC_PREREQ(2, 16)
1265
#pragma GCC diagnostic pop
1268
/* This process had nothing to say at this time */
1272
/* Before reading, make the process' data buffer large enough */
1273
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1274
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1275
+ (size_t) BUFFER_SIZE);
1276
if(new_buffer == NULL){
1277
error(0, errno, "malloc");
1278
exitstatus = EX_OSERR;
1281
proc->buffer = new_buffer;
1282
proc->buffer_size += BUFFER_SIZE;
1284
/* Read from the process */
1285
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1287
+ proc->buffer_length,
1290
/* Read error from this process; ignore the error */
1298
proc->buffer_length += (size_t) sret;
1306
if(plugin_list == NULL or (exitstatus != EXIT_SUCCESS
1307
and exitstatus != EX_OK)){
1308
/* Fallback if all plugins failed, none are found or an error
1311
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1312
char *passwordbuffer = getpass("Password: ");
1313
size_t len = strlen(passwordbuffer);
1314
/* Strip trailing newline */
1315
if(len > 0 and passwordbuffer[len-1] == '\n'){
1316
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1319
bret = print_out_password(passwordbuffer, len);
1321
error(0, errno, "print_out_password");
1322
exitstatus = EX_IOERR;
1326
/* Restore old signal handler */
1327
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1329
error(0, errno, "sigaction");
1330
exitstatus = EX_OSERR;
1333
if(custom_argv != NULL){
1334
for(char **arg = custom_argv+1; *arg != NULL; arg++){
1346
/* Kill the processes */
1347
for(plugin *p = plugin_list; p != NULL; p = p->next){
1350
ret = kill(p->pid, SIGTERM);
1351
if(ret == -1 and errno != ESRCH){
1352
/* Set-uid proccesses might not get closed */
1353
error(0, errno, "kill");
1358
/* Wait for any remaining child processes to terminate */
1362
if(errno != ECHILD){
1363
error(0, errno, "wait");
1369
free(pluginhelperdir);