46
47
fcntl(), setuid(), setgid(),
47
48
F_GETFD, F_SETFD, FD_CLOEXEC,
48
49
access(), pipe(), fork(), close()
49
dup2, STDOUT_FILENO, _exit(),
50
dup2(), STDOUT_FILENO, _exit(),
50
51
execv(), write(), read(),
52
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strtok, strlen(), strcpy(),
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
56
#include <errno.h> /* errno */
57
57
#include <argp.h> /* struct argp_option, struct
58
58
argp_state, struct argp,
59
59
argp_parse(), ARGP_ERR_UNKNOWN,
60
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
60
ARGP_KEY_END, ARGP_KEY_ARG,
61
62
#include <signal.h> /* struct sigaction, sigemptyset(),
62
63
sigaddset(), sigaction(),
63
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
65
SIG_UNBLOCK, kill(), sig_atomic_t
65
67
#include <errno.h> /* errno, EBADF */
68
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
67
70
#define BUFFER_SIZE 256
69
const char *argp_program_version = "mandos-client 1.0";
72
#define PDIR "/lib/mandos/plugins.d"
73
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
75
const char *argp_program_version = "plugin-runner " VERSION;
70
76
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
78
typedef struct plugin{
79
char *name; /* can be NULL or any plugin name */
74
typedef struct process{
86
/* Variables used for running processes*/
78
90
size_t buffer_size;
79
91
size_t buffer_length;
93
volatile sig_atomic_t completed;
86
typedef struct plugin{
87
char *name; /* can be NULL or any plugin name */
91
95
struct plugin *next;
94
static plugin *getplugin(char *name, plugin **plugin_list){
95
for (plugin *p = *plugin_list; p != NULL; p = p->next){
97
or (p->name and name and (strcmp(p->name, name) == 0))){
98
static plugin *plugin_list = NULL;
100
/* Gets an existing plugin based on name,
101
or if none is found, creates a new one */
102
static plugin *getplugin(char *name){
103
/* Check for exiting plugin with that name */
104
for(plugin *p = plugin_list; p != NULL; p = p->next){
106
or (p->name and name and (strcmp(p->name, name) == 0))){
101
110
/* Create a new plugin */
102
111
plugin *new_plugin = malloc(sizeof(plugin));
103
if (new_plugin == NULL){
107
new_plugin->name = name;
112
if(new_plugin == NULL){
115
char *copy_name = NULL;
117
copy_name = strdup(name);
118
if(copy_name == NULL){
124
*new_plugin = (plugin){ .name = copy_name,
127
.next = plugin_list };
108
129
new_plugin->argv = malloc(sizeof(char *) * 2);
109
if (new_plugin->argv == NULL){
130
if(new_plugin->argv == NULL){
113
new_plugin->argv[0] = name;
135
new_plugin->argv[0] = copy_name;
114
136
new_plugin->argv[1] = NULL;
115
new_plugin->argc = 1;
116
new_plugin->disabled = false;
117
new_plugin->next = *plugin_list;
138
new_plugin->environ = malloc(sizeof(char *));
139
if(new_plugin->environ == NULL){
141
free(new_plugin->argv);
145
new_plugin->environ[0] = NULL;
118
147
/* Append the new plugin to the list */
119
*plugin_list = new_plugin;
148
plugin_list = new_plugin;
120
149
return new_plugin;
123
static void addargument(plugin *p, char *arg){
124
p->argv[p->argc] = arg;
125
p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
126
if (p->argv == NULL){
131
p->argv[p->argc] = NULL;
152
/* Helper function for add_argument and add_environment */
153
static bool add_to_char_array(const char *new, char ***array,
155
/* Resize the pointed-to array to hold one more pointer */
156
*array = realloc(*array, sizeof(char *)
157
* (size_t) ((*len) + 2));
162
/* Make a copy of the new string */
163
char *copy = strdup(new);
167
/* Insert the copy */
168
(*array)[*len] = copy;
170
/* Add a new terminating NULL pointer to the last element */
171
(*array)[*len] = NULL;
175
/* Add to a plugin's argument vector */
176
static bool add_argument(plugin *p, const char *arg){
180
return add_to_char_array(arg, &(p->argv), &(p->argc));
183
/* Add to a plugin's environment */
184
static bool add_environment(plugin *p, const char *def, bool replace){
188
/* namelen = length of name of environment variable */
189
size_t namelen = (size_t)(strchrnul(def, '=') - def);
190
/* Search for this environment variable */
191
for(char **e = p->environ; *e != NULL; e++){
192
if(strncmp(*e, def, namelen + 1) == 0){
193
/* It already exists */
195
char *new = realloc(*e, strlen(def) + 1);
205
return add_to_char_array(def, &(p->environ), &(p->envc));
221
346
{ .name = "global-options", .key = 'g',
222
347
.arg = "OPTION[,OPTION[,...]]",
223
348
.doc = "Options passed to all plugins" },
349
{ .name = "global-env", .key = 'G',
351
.doc = "Environment variable passed to all plugins" },
224
352
{ .name = "options-for", .key = 'o',
225
353
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
226
354
.doc = "Options passed only to specified plugin" },
355
{ .name = "env-for", .key = 'E',
356
.arg = "PLUGIN:ENV=value",
357
.doc = "Environment variable passed to specified plugin" },
227
358
{ .name = "disable", .key = 'd',
229
360
.doc = "Disable a specific plugin", .group = 1 },
361
{ .name = "enable", .key = 'e',
363
.doc = "Enable a specific plugin", .group = 1 },
230
364
{ .name = "plugin-dir", .key = 128,
231
365
.arg = "DIRECTORY",
232
366
.doc = "Specify a different plugin directory", .group = 2 },
233
{ .name = "userid", .key = 129,
234
.arg = "ID", .flags = 0,
235
.doc = "User ID the plugins will run as", .group = 2 },
236
{ .name = "groupid", .key = 130,
237
.arg = "ID", .flags = 0,
238
.doc = "Group ID the plugins will run as", .group = 2 },
239
{ .name = "debug", .key = 131,
240
.doc = "Debug mode", .group = 3 },
367
{ .name = "config-file", .key = 129,
369
.doc = "Specify a different configuration file", .group = 2 },
370
{ .name = "userid", .key = 130,
371
.arg = "ID", .flags = 0,
372
.doc = "User ID the plugins will run as", .group = 3 },
373
{ .name = "groupid", .key = 131,
374
.arg = "ID", .flags = 0,
375
.doc = "Group ID the plugins will run as", .group = 3 },
376
{ .name = "debug", .key = 132,
377
.doc = "Debug mode", .group = 4 },
244
error_t parse_opt (int key, char *arg, struct argp_state *state) {
245
/* Get the INPUT argument from `argp_parse', which we know is a
246
pointer to our plugin list pointer. */
247
plugin **plugins = state->input;
251
char *p = strtok(arg, ",");
253
addargument(getplugin(NULL, plugins), p);
254
p = strtok(NULL, ",");
260
char *name = strtok(arg, ":");
261
char *p = strtok(NULL, ":");
265
addargument(getplugin(name, plugins), p);
266
p = strtok(NULL, ",");
273
getplugin(arg, plugins)->disabled = true;
280
uid = (uid_t)strtol(arg, NULL, 10);
283
gid = (gid_t)strtol(arg, NULL, 10);
381
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
struct argp_state *state){
384
case 'g': /* --global-options */
387
while((plugin_option = strsep(&arg, ",")) != NULL){
388
if(plugin_option[0] == '\0'){
391
if(not add_argument(getplugin(NULL), plugin_option)){
392
perror("add_argument");
393
return ARGP_ERR_UNKNOWN;
398
case 'G': /* --global-env */
402
if(not add_environment(getplugin(NULL), arg, true)){
403
perror("add_environment");
406
case 'o': /* --options-for */
408
char *plugin_name = strsep(&arg, ":");
409
if(plugin_name[0] == '\0'){
413
while((plugin_option = strsep(&arg, ",")) != NULL){
414
if(not add_argument(getplugin(plugin_name), plugin_option)){
415
perror("add_argument");
416
return ARGP_ERR_UNKNOWN;
421
case 'E': /* --env-for */
426
char *envdef = strchr(arg, ':');
431
if(not add_environment(getplugin(arg), envdef+1, true)){
432
perror("add_environment");
436
case 'd': /* --disable */
438
plugin *p = getplugin(arg);
440
return ARGP_ERR_UNKNOWN;
445
case 'e': /* --enable */
447
plugin *p = getplugin(arg);
449
return ARGP_ERR_UNKNOWN;
454
case 128: /* --plugin-dir */
456
plugindir = strdup(arg);
457
if(plugindir == NULL){
461
case 129: /* --config-file */
462
/* This is already done by parse_opt_config_file() */
464
case 130: /* --userid */
465
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
466
if(ret < 1 or tmpmax != (uid_t)tmpmax
467
or arg[numchars] != '\0'){
468
fprintf(stderr, "Bad user ID number: \"%s\", using %"
469
PRIdMAX "\n", arg, (intmax_t)uid);
474
case 131: /* --groupid */
475
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
476
if(ret < 1 or tmpmax != (gid_t)tmpmax
477
or arg[numchars] != '\0'){
478
fprintf(stderr, "Bad group ID number: \"%s\", using %"
479
PRIdMAX "\n", arg, (intmax_t)gid);
484
case 132: /* --debug */
289
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
297
return ARGP_ERR_UNKNOWN;
302
plugin *plugin_list = NULL;
304
struct argp argp = { .options = options, .parser = parse_opt,
305
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
488
* When adding more options before this line, remember to also add a
489
* "case" to the "parse_opt_config_file" function below.
492
/* Cryptsetup always passes an argument, which is an empty
493
string if "none" was specified in /etc/crypttab. So if
494
argument was empty, we ignore it silently. */
496
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
502
return ARGP_ERR_UNKNOWN;
507
/* This option parser is the same as parse_opt() above, except it
508
ignores everything but the --config-file option. */
509
error_t parse_opt_config_file(int key, char *arg,
510
__attribute__((unused))
511
struct argp_state *state){
513
case 'g': /* --global-options */
514
case 'G': /* --global-env */
515
case 'o': /* --options-for */
516
case 'E': /* --env-for */
517
case 'd': /* --disable */
518
case 'e': /* --enable */
519
case 128: /* --plugin-dir */
521
case 129: /* --config-file */
523
argfile = strdup(arg);
528
case 130: /* --userid */
529
case 131: /* --groupid */
530
case 132: /* --debug */
535
return ARGP_ERR_UNKNOWN;
540
struct argp argp = { .options = options,
541
.parser = parse_opt_config_file,
306
543
.doc = "Mandos plugin runner -- Run plugins" };
308
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
309
if (ret == ARGP_ERR_UNKNOWN){
545
/* Parse using parse_opt_config_file() in order to get the custom
546
config file location, if any. */
547
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
548
if(ret == ARGP_ERR_UNKNOWN){
310
549
fprintf(stderr, "Unknown error while parsing arguments\n");
311
550
exitstatus = EXIT_FAILURE;
316
/* This is a mangled argument in the form of
317
"+--option+--other-option=parameter+--yet-another-option", etc */
318
/* Make new argc and argv vars, and call argp_parse() again. */
319
plus_options++; /* skip the first '+' character */
320
const char delims[] = "+";
323
plus_argv = malloc(sizeof(char*) * 2);
324
if(plus_argv == NULL){
554
/* Reset to the normal argument parser */
555
argp.parser = parse_opt;
557
/* Open the configfile if available */
559
conffp = fopen(AFILE, "r");
561
conffp = fopen(argfile, "r");
564
char *org_line = NULL;
565
char *p, *arg, *new_arg, *line;
567
const char whitespace_delims[] = " \r\t\f\v\n";
568
const char comment_delim[] = "#";
571
custom_argv = malloc(sizeof(char*) * 2);
572
if(custom_argv == NULL){
325
573
perror("malloc");
326
574
exitstatus = EXIT_FAILURE;
329
plus_argv[0] = argv[0];
331
arg = strtok(plus_options, delims); /* Get first argument */
334
plus_argv = realloc(plus_argv, sizeof(char *)
335
* ((unsigned int) new_argc + 1));
336
if(plus_argv == NULL){
338
exitstatus = EXIT_FAILURE;
341
plus_argv[new_argc-1] = arg;
342
plus_argv[new_argc] = NULL;
343
arg = strtok(NULL, delims); /* Get next argument */
345
ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
346
if (ret == ARGP_ERR_UNKNOWN){
577
custom_argv[0] = argv[0];
578
custom_argv[1] = NULL;
580
/* for each line in the config file, strip whitespace and ignore
583
sret = getline(&org_line, &size, conffp);
589
arg = strsep(&line, comment_delim);
590
while((p = strsep(&arg, whitespace_delims)) != NULL){
597
exitstatus = EXIT_FAILURE;
603
custom_argv = realloc(custom_argv, sizeof(char *)
604
* ((unsigned int) custom_argc + 1));
605
if(custom_argv == NULL){
607
exitstatus = EXIT_FAILURE;
611
custom_argv[custom_argc-1] = new_arg;
612
custom_argv[custom_argc] = NULL;
617
/* Check for harmful errors and go to fallback. Other errors might
618
not affect opening plugins */
619
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
621
exitstatus = EXIT_FAILURE;
625
/* If there was any arguments from configuration file,
626
pass them to parser as command arguments */
627
if(custom_argv != NULL){
628
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
630
if(ret == ARGP_ERR_UNKNOWN){
347
631
fprintf(stderr, "Unknown error while parsing arguments\n");
348
632
exitstatus = EXIT_FAILURE;
637
/* Parse actual command line arguments, to let them override the
639
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
640
if(ret == ARGP_ERR_UNKNOWN){
641
fprintf(stderr, "Unknown error while parsing arguments\n");
642
exitstatus = EXIT_FAILURE;
354
647
for(plugin *p = plugin_list; p != NULL; p=p->next){
355
648
fprintf(stderr, "Plugin: %s has %d arguments\n",
545
882
above and must now close it manually here. */
548
if(execv(filename, p->argv) < 0){
885
if(p->environ[0] == NULL){
886
if(execv(filename, p->argv) < 0){
891
if(execve(filename, p->argv, p->environ) < 0){
899
close(pipefd[1]); /* Close unused write end of pipe */
556
close(pipefd[1]); /* close unused write end of pipe */
557
process *new_process = malloc(sizeof(process));
558
if (new_process == NULL){
560
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
901
plugin *new_plugin = getplugin(dirst->d_name);
902
if(new_plugin == NULL){
904
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
562
perror("sigprocmask");
906
perror("sigprocmask");
564
908
exitstatus = EXIT_FAILURE;
568
*new_process = (struct process){ .pid = pid,
570
.next = process_list };
572
process_list = new_process;
912
new_plugin->pid = pid;
913
new_plugin->fd = pipefd[0];
573
915
/* Unblock SIGCHLD so signal handler can be run if this process
574
916
has already completed */
575
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
917
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
577
919
perror("sigprocmask");
578
920
exitstatus = EXIT_FAILURE;
582
FD_SET(new_process->fd, &rfds_all);
584
if (maxfd < new_process->fd){
585
maxfd = new_process->fd;
590
/* Free the plugin list */
591
for(plugin *next; plugin_list != NULL; plugin_list = next){
592
next = plugin_list->next;
593
free(plugin_list->argv);
924
FD_SET(new_plugin->fd, &rfds_all);
926
if(maxfd < new_plugin->fd){
927
maxfd = new_plugin->fd;
600
if (process_list == NULL){
601
fprintf(stderr, "No plugin processes started. Incorrect plugin"
933
free_plugin(getplugin(NULL));
935
for(plugin *p = plugin_list; p != NULL; p = p->next){
940
fprintf(stderr, "No plugin processes started. Incorrect plugin"
946
/* Main loop while running plugins exist */
606
948
fd_set rfds = rfds_all;
607
949
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
608
if (select_ret == -1){
950
if(select_ret == -1){
609
951
perror("select");
610
952
exitstatus = EXIT_FAILURE;
613
955
/* OK, now either a process completed, or something can be read
614
956
from one of them */
615
for(process *proc = process_list; proc ; proc = proc->next){
957
for(plugin *proc = plugin_list; proc != NULL;){
616
958
/* Is this process completely done? */
617
if(proc->eof and proc->completed){
959
if(proc->completed and proc->eof){
618
960
/* Only accept the plugin output if it exited cleanly */
619
961
if(not WIFEXITED(proc->status)
620
962
or WEXITSTATUS(proc->status) != 0){
621
963
/* Bad exit by plugin */
623
966
if(WIFEXITED(proc->status)){
624
fprintf(stderr, "Plugin %u exited with status %d\n",
625
(unsigned int) (proc->pid),
967
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
968
" status %d\n", proc->name,
969
(intmax_t) (proc->pid),
626
970
WEXITSTATUS(proc->status));
627
} else if(WIFSIGNALED(proc->status)) {
628
fprintf(stderr, "Plugin %u killed by signal %d\n",
629
(unsigned int) (proc->pid),
971
} else if(WIFSIGNALED(proc->status)){
972
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
973
" signal %d\n", proc->name,
974
(intmax_t) (proc->pid),
630
975
WTERMSIG(proc->status));
631
976
} else if(WCOREDUMP(proc->status)){
632
fprintf(stderr, "Plugin %d dumped core\n",
633
(unsigned int) (proc->pid));
977
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
978
" core\n", proc->name, (intmax_t) (proc->pid));
636
982
/* Remove the plugin */
637
983
FD_CLR(proc->fd, &rfds_all);
638
985
/* Block signal while modifying process_list */
639
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
986
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
641
988
perror("sigprocmask");
642
989
exitstatus = EXIT_FAILURE;
645
/* Delete this process entry from the list */
646
if(process_list == proc){
647
/* First one - simple */
648
process_list = proc->next;
650
/* Second one or later */
651
for(process *p = process_list; p != NULL; p = p->next){
653
p->next = proc->next;
993
plugin *next_plugin = proc->next;
658
997
/* We are done modifying process list, so unblock signal */
659
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
998
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
662
1001
perror("sigprocmask");
666
/* We deleted this process from the list, so we can't go
667
proc->next. Therefore, start over from the beginning of
1002
exitstatus = EXIT_FAILURE;
1006
if(plugin_list == NULL){
671
1013
/* This process exited nicely, so print its buffer */
673
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1015
bool bret = print_out_password(proc->buffer,
1016
proc->buffer_length);
675
1018
perror("print_out_password");
676
1019
exitstatus = EXIT_FAILURE;
680
1024
/* This process has not completed. Does it have any output? */
681
1025
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
682
1026
/* This process had nothing to say at this time */
685
1030
/* Before reading, make the process' data buffer large enough */
686
1031
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
687
1032
proc->buffer = realloc(proc->buffer, proc->buffer_size
688
1033
+ (size_t) BUFFER_SIZE);
689
if (proc->buffer == NULL){
1034
if(proc->buffer == NULL){
690
1035
perror("malloc");
691
1036
exitstatus = EXIT_FAILURE;
694
1039
proc->buffer_size += BUFFER_SIZE;
696
1041
/* Read from the process */
697
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1042
sret = read(proc->fd, proc->buffer + proc->buffer_length,
700
1045
/* Read error from this process; ignore the error */
705
1051
proc->eof = true;
707
proc->buffer_length += (size_t) ret;
1053
proc->buffer_length += (size_t) sret;
715
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
716
/* Fallback if all plugins failed or an error occured */
1061
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1062
/* Fallback if all plugins failed, none are found or an error
718
1065
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
719
1066
char *passwordbuffer = getpass("Password: ");
720
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1067
size_t len = strlen(passwordbuffer);
1068
/* Strip trailing newline */
1069
if(len > 0 and passwordbuffer[len-1] == '\n'){
1070
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1073
bret = print_out_password(passwordbuffer, len);
722
1075
perror("print_out_password");
723
1076
exitstatus = EXIT_FAILURE;
728
1080
/* Restore old signal handler */
729
sigaction(SIGCHLD, &old_sigchld_action, NULL);
733
/* Free the plugin list */
734
for(plugin *next; plugin_list != NULL; plugin_list = next){
735
next = plugin_list->next;
736
free(plugin_list->argv);
1081
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1083
perror("sigaction");
1084
exitstatus = EXIT_FAILURE;
1087
if(custom_argv != NULL){
1088
for(char **arg = custom_argv+1; *arg != NULL; arg++){
740
1094
if(dir != NULL){
744
/* Free the process list and kill the processes */
745
for(process *next; process_list != NULL; process_list = next){
746
next = process_list->next;
747
close(process_list->fd);
748
ret = kill(process_list->pid, SIGTERM);
749
if(ret == -1 and errno != ESRCH){
750
/* set-uid proccesses migth not get closed */
1098
/* Kill the processes */
1099
for(plugin *p = plugin_list; p != NULL; p = p->next){
1102
ret = kill(p->pid, SIGTERM);
1103
if(ret == -1 and errno != ESRCH){
1104
/* Set-uid proccesses might not get closed */
753
free(process_list->buffer);
757
1110
/* Wait for any remaining child processes to terminate */