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
65
SIG_UNBLOCK, kill() */
65
66
#include <errno.h> /* errno, EBADF */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
67
69
#define BUFFER_SIZE 256
69
const char *argp_program_version = "mandos-client 1.0";
71
#define PDIR "/lib/mandos/plugins.d"
72
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
74
const char *argp_program_version = "plugin-runner " VERSION;
70
75
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
77
typedef struct plugin{
78
char *name; /* can be NULL or any plugin name */
74
typedef struct process{
85
/* Variables used for running processes*/
78
89
size_t buffer_size;
79
90
size_t buffer_length;
92
volatile sig_atomic_t completed;
86
typedef struct plugin{
87
char *name; /* can be NULL or any plugin name */
91
94
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))){
97
static plugin *plugin_list = NULL;
99
/* Gets an existing plugin based on name,
100
or if none is found, creates a new one */
101
static plugin *getplugin(char *name){
102
/* Check for exiting plugin with that name */
103
for(plugin *p = plugin_list; p != NULL; p = p->next){
105
or (p->name and name and (strcmp(p->name, name) == 0))){
101
109
/* Create a new plugin */
102
110
plugin *new_plugin = malloc(sizeof(plugin));
103
if (new_plugin == NULL){
107
new_plugin->name = name;
111
if(new_plugin == NULL){
114
char *copy_name = NULL;
116
copy_name = strdup(name);
117
if(copy_name == NULL){
123
*new_plugin = (plugin){ .name = copy_name,
126
.next = plugin_list };
108
128
new_plugin->argv = malloc(sizeof(char *) * 2);
109
if (new_plugin->argv == NULL){
129
if(new_plugin->argv == NULL){
113
new_plugin->argv[0] = name;
134
new_plugin->argv[0] = copy_name;
114
135
new_plugin->argv[1] = NULL;
115
new_plugin->argc = 1;
116
new_plugin->disabled = false;
117
new_plugin->next = *plugin_list;
137
new_plugin->environ = malloc(sizeof(char *));
138
if(new_plugin->environ == NULL){
140
free(new_plugin->argv);
144
new_plugin->environ[0] = NULL;
118
146
/* Append the new plugin to the list */
119
*plugin_list = new_plugin;
147
plugin_list = new_plugin;
120
148
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;
151
/* Helper function for add_argument and add_environment */
152
static bool add_to_char_array(const char *new, char ***array,
154
/* Resize the pointed-to array to hold one more pointer */
155
*array = realloc(*array, sizeof(char *)
156
* (size_t) ((*len) + 2));
161
/* Make a copy of the new string */
162
char *copy = strdup(new);
166
/* Insert the copy */
167
(*array)[*len] = copy;
169
/* Add a new terminating NULL pointer to the last element */
170
(*array)[*len] = NULL;
174
/* Add to a plugin's argument vector */
175
static bool add_argument(plugin *p, const char *arg){
179
return add_to_char_array(arg, &(p->argv), &(p->argc));
182
/* Add to a plugin's environment */
183
static bool add_environment(plugin *p, const char *def, bool replace){
187
/* namelen = length of name of environment variable */
188
size_t namelen = (size_t)(strchrnul(def, '=') - def);
189
/* Search for this environment variable */
190
for(char **e = p->environ; *e != NULL; e++){
191
if(strncmp(*e, def, namelen + 1) == 0){
192
/* It already exists */
194
char *new = realloc(*e, strlen(def) + 1);
204
return add_to_char_array(def, &(p->environ), &(p->envc));
223
345
{ .name = "global-options", .key = 'g',
224
346
.arg = "OPTION[,OPTION[,...]]",
225
347
.doc = "Options passed to all plugins" },
348
{ .name = "global-env", .key = 'G',
350
.doc = "Environment variable passed to all plugins" },
226
351
{ .name = "options-for", .key = 'o',
227
352
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
228
353
.doc = "Options passed only to specified plugin" },
354
{ .name = "env-for", .key = 'E',
355
.arg = "PLUGIN:ENV=value",
356
.doc = "Environment variable passed to specified plugin" },
229
357
{ .name = "disable", .key = 'd',
231
359
.doc = "Disable a specific plugin", .group = 1 },
360
{ .name = "enable", .key = 'e',
362
.doc = "Enable a specific plugin", .group = 1 },
232
363
{ .name = "plugin-dir", .key = 128,
233
364
.arg = "DIRECTORY",
234
365
.doc = "Specify a different plugin directory", .group = 2 },
235
{ .name = "userid", .key = 129,
236
.arg = "ID", .flags = 0,
237
.doc = "User ID the plugins will run as", .group = 2 },
238
{ .name = "groupid", .key = 130,
239
.arg = "ID", .flags = 0,
240
.doc = "Group ID the plugins will run as", .group = 2 },
241
{ .name = "debug", .key = 131,
242
.doc = "Debug mode", .group = 3 },
366
{ .name = "config-file", .key = 129,
368
.doc = "Specify a different configuration file", .group = 2 },
369
{ .name = "userid", .key = 130,
370
.arg = "ID", .flags = 0,
371
.doc = "User ID the plugins will run as", .group = 3 },
372
{ .name = "groupid", .key = 131,
373
.arg = "ID", .flags = 0,
374
.doc = "Group ID the plugins will run as", .group = 3 },
375
{ .name = "debug", .key = 132,
376
.doc = "Debug mode", .group = 4 },
246
error_t parse_opt (int key, char *arg, struct argp_state *state) {
247
/* Get the INPUT argument from `argp_parse', which we know is a
248
pointer to our plugin list pointer. */
249
plugin **plugins = state->input;
253
char *p = strtok(arg, ",");
255
addargument(getplugin(NULL, plugins), p);
256
p = strtok(NULL, ",");
262
char *name = strtok(arg, ":");
263
char *p = strtok(NULL, ":");
267
addargument(getplugin(name, plugins), p);
268
p = strtok(NULL, ",");
275
getplugin(arg, plugins)->disabled = true;
282
uid = (uid_t)strtol(arg, NULL, 10);
285
gid = (gid_t)strtol(arg, NULL, 10);
380
error_t parse_opt(int key, char *arg, __attribute__((unused))
381
struct argp_state *state){
383
case 'g': /* --global-options */
386
while((p = strsep(&arg, ",")) != NULL){
390
if(not add_argument(getplugin(NULL), p)){
391
perror("add_argument");
392
return ARGP_ERR_UNKNOWN;
397
case 'G': /* --global-env */
401
if(not add_environment(getplugin(NULL), arg, true)){
402
perror("add_environment");
405
case 'o': /* --options-for */
407
char *p_name = strsep(&arg, ":");
408
if(p_name[0] == '\0' or arg == NULL){
411
char *opt = strsep(&arg, ":");
412
if(opt[0] == '\0' or opt == NULL){
416
while((p = strsep(&opt, ",")) != NULL){
420
if(not add_argument(getplugin(p_name), p)){
421
perror("add_argument");
422
return ARGP_ERR_UNKNOWN;
427
case 'E': /* --env-for */
432
char *envdef = strchr(arg, ':');
437
if(not add_environment(getplugin(arg), envdef+1, true)){
438
perror("add_environment");
442
case 'd': /* --disable */
444
plugin *p = getplugin(arg);
446
return ARGP_ERR_UNKNOWN;
451
case 'e': /* --enable */
453
plugin *p = getplugin(arg);
455
return ARGP_ERR_UNKNOWN;
460
case 128: /* --plugin-dir */
462
plugindir = strdup(arg);
463
if(plugindir == NULL){
467
case 129: /* --config-file */
468
/* This is already done by parse_opt_config_file() */
470
case 130: /* --userid */
471
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
472
if(ret < 1 or tmpmax != (uid_t)tmpmax
473
or arg[numchars] != '\0'){
474
fprintf(stderr, "Bad user ID number: \"%s\", using %"
475
PRIdMAX "\n", arg, (intmax_t)uid);
480
case 131: /* --groupid */
481
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
482
if(ret < 1 or tmpmax != (gid_t)tmpmax
483
or arg[numchars] != '\0'){
484
fprintf(stderr, "Bad group ID number: \"%s\", using %"
485
PRIdMAX "\n", arg, (intmax_t)gid);
490
case 132: /* --debug */
291
if(plus_options != NULL or arg == NULL or arg[0] != '+'){
299
return ARGP_ERR_UNKNOWN;
304
plugin *plugin_list = NULL;
306
struct argp argp = { .options = options, .parser = parse_opt,
307
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
494
* When adding more options before this line, remember to also add a
495
* "case" to the "parse_opt_config_file" function below.
498
/* Cryptsetup always passes an argument, which is an empty
499
string if "none" was specified in /etc/crypttab. So if
500
argument was empty, we ignore it silently. */
502
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
508
return ARGP_ERR_UNKNOWN;
513
/* This option parser is the same as parse_opt() above, except it
514
ignores everything but the --config-file option. */
515
error_t parse_opt_config_file(int key, char *arg,
516
__attribute__((unused))
517
struct argp_state *state){
519
case 'g': /* --global-options */
520
case 'G': /* --global-env */
521
case 'o': /* --options-for */
522
case 'E': /* --env-for */
523
case 'd': /* --disable */
524
case 'e': /* --enable */
525
case 128: /* --plugin-dir */
527
case 129: /* --config-file */
529
argfile = strdup(arg);
534
case 130: /* --userid */
535
case 131: /* --groupid */
536
case 132: /* --debug */
541
return ARGP_ERR_UNKNOWN;
546
struct argp argp = { .options = options,
547
.parser = parse_opt_config_file,
308
549
.doc = "Mandos plugin runner -- Run plugins" };
310
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
311
if (ret == ARGP_ERR_UNKNOWN){
551
/* Parse using parse_opt_config_file() in order to get the custom
552
config file location, if any. */
553
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
554
if(ret == ARGP_ERR_UNKNOWN){
312
555
fprintf(stderr, "Unknown error while parsing arguments\n");
313
556
exitstatus = EXIT_FAILURE;
318
/* This is a mangled argument in the form of
319
"+--option+--other-option=parameter+--yet-another-option", etc */
320
/* Make new argc and argv vars, and call argp_parse() again. */
321
plus_options++; /* skip the first '+' character */
322
const char delims[] = "+";
325
plus_argv = malloc(sizeof(char*) * 2);
326
if(plus_argv == NULL){
560
/* Reset to the normal argument parser */
561
argp.parser = parse_opt;
563
/* Open the configfile if available */
565
conffp = fopen(AFILE, "r");
567
conffp = fopen(argfile, "r");
570
char *org_line = NULL;
571
char *p, *arg, *new_arg, *line;
573
const char whitespace_delims[] = " \r\t\f\v\n";
574
const char comment_delim[] = "#";
577
custom_argv = malloc(sizeof(char*) * 2);
578
if(custom_argv == NULL){
327
579
perror("malloc");
328
580
exitstatus = EXIT_FAILURE;
331
plus_argv[0] = argv[0];
333
arg = strtok(plus_options, delims); /* Get first argument */
336
plus_argv = realloc(plus_argv, sizeof(char *)
337
* ((unsigned int) new_argc + 1));
338
if(plus_argv == NULL){
340
exitstatus = EXIT_FAILURE;
343
plus_argv[new_argc-1] = arg;
344
plus_argv[new_argc] = NULL;
345
arg = strtok(NULL, delims); /* Get next argument */
347
ret = argp_parse (&argp, new_argc, plus_argv, 0, 0, &plugin_list);
348
if (ret == ARGP_ERR_UNKNOWN){
583
custom_argv[0] = argv[0];
584
custom_argv[1] = NULL;
586
/* for each line in the config file, strip whitespace and ignore
589
sret = getline(&org_line, &size, conffp);
595
arg = strsep(&line, comment_delim);
596
while((p = strsep(&arg, whitespace_delims)) != NULL){
603
exitstatus = EXIT_FAILURE;
609
custom_argv = realloc(custom_argv, sizeof(char *)
610
* ((unsigned int) custom_argc + 1));
611
if(custom_argv == NULL){
613
exitstatus = EXIT_FAILURE;
617
custom_argv[custom_argc-1] = new_arg;
618
custom_argv[custom_argc] = NULL;
623
/* Check for harmful errors and go to fallback. Other errors might
624
not affect opening plugins */
625
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
627
exitstatus = EXIT_FAILURE;
631
/* If there was any arguments from configuration file,
632
pass them to parser as command arguments */
633
if(custom_argv != NULL){
634
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
636
if(ret == ARGP_ERR_UNKNOWN){
349
637
fprintf(stderr, "Unknown error while parsing arguments\n");
350
638
exitstatus = EXIT_FAILURE;
643
/* Parse actual command line arguments, to let them override the
645
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
646
if(ret == ARGP_ERR_UNKNOWN){
647
fprintf(stderr, "Unknown error while parsing arguments\n");
648
exitstatus = EXIT_FAILURE;
356
653
for(plugin *p = plugin_list; p != NULL; p=p->next){
357
654
fprintf(stderr, "Plugin: %s has %d arguments\n",
551
888
above and must now close it manually here. */
554
if(execv(filename, p->argv) < 0){
891
if(p->environ[0] == NULL){
892
if(execv(filename, p->argv) < 0){
897
if(execve(filename, p->argv, p->environ) < 0){
905
close(pipefd[1]); /* Close unused write end of pipe */
562
close(pipefd[1]); /* close unused write end of pipe */
563
process *new_process = malloc(sizeof(process));
564
if (new_process == NULL){
566
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
907
plugin *new_plugin = getplugin(dirst->d_name);
908
if(new_plugin == NULL){
910
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
568
perror("sigprocmask");
912
perror("sigprocmask");
570
914
exitstatus = EXIT_FAILURE;
574
*new_process = (struct process){ .pid = pid,
576
.next = process_list };
578
process_list = new_process;
918
new_plugin->pid = pid;
919
new_plugin->fd = pipefd[0];
579
921
/* Unblock SIGCHLD so signal handler can be run if this process
580
922
has already completed */
581
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
923
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
583
925
perror("sigprocmask");
584
926
exitstatus = EXIT_FAILURE;
588
FD_SET(new_process->fd, &rfds_all);
590
if (maxfd < new_process->fd){
591
maxfd = new_process->fd;
596
/* Free the plugin list */
597
for(plugin *next; plugin_list != NULL; plugin_list = next){
598
next = plugin_list->next;
599
free(plugin_list->argv);
930
FD_SET(new_plugin->fd, &rfds_all);
932
if(maxfd < new_plugin->fd){
933
maxfd = new_plugin->fd;
606
if (process_list == NULL){
607
fprintf(stderr, "No plugin processes started. Incorrect plugin"
940
for(plugin *p = plugin_list; p != NULL; p = p->next){
945
fprintf(stderr, "No plugin processes started. Incorrect plugin"
951
/* Main loop while running plugins exist */
612
953
fd_set rfds = rfds_all;
613
954
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
614
if (select_ret == -1){
955
if(select_ret == -1){
615
956
perror("select");
616
957
exitstatus = EXIT_FAILURE;
619
960
/* OK, now either a process completed, or something can be read
620
961
from one of them */
621
for(process *proc = process_list; proc ; proc = proc->next){
962
for(plugin *proc = plugin_list; proc != NULL;){
622
963
/* Is this process completely done? */
623
if(proc->eof and proc->completed){
964
if(proc->completed and proc->eof){
624
965
/* Only accept the plugin output if it exited cleanly */
625
966
if(not WIFEXITED(proc->status)
626
967
or WEXITSTATUS(proc->status) != 0){
627
968
/* Bad exit by plugin */
629
971
if(WIFEXITED(proc->status)){
630
fprintf(stderr, "Plugin %u exited with status %d\n",
631
(unsigned int) (proc->pid),
972
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
973
" status %d\n", proc->name,
974
(intmax_t) (proc->pid),
632
975
WEXITSTATUS(proc->status));
633
} else if(WIFSIGNALED(proc->status)) {
634
fprintf(stderr, "Plugin %u killed by signal %d\n",
635
(unsigned int) (proc->pid),
976
} else if(WIFSIGNALED(proc->status)){
977
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
978
" signal %d\n", proc->name,
979
(intmax_t) (proc->pid),
636
980
WTERMSIG(proc->status));
637
981
} else if(WCOREDUMP(proc->status)){
638
fprintf(stderr, "Plugin %d dumped core\n",
639
(unsigned int) (proc->pid));
982
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
983
" core\n", proc->name, (intmax_t) (proc->pid));
642
987
/* Remove the plugin */
643
988
FD_CLR(proc->fd, &rfds_all);
644
990
/* Block signal while modifying process_list */
645
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
991
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
647
993
perror("sigprocmask");
648
994
exitstatus = EXIT_FAILURE;
651
/* Delete this process entry from the list */
652
if(process_list == proc){
653
/* First one - simple */
654
process_list = proc->next;
656
/* Second one or later */
657
for(process *p = process_list; p != NULL; p = p->next){
659
p->next = proc->next;
998
plugin *next_plugin = proc->next;
664
1002
/* We are done modifying process list, so unblock signal */
665
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1003
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
668
1006
perror("sigprocmask");
672
/* We deleted this process from the list, so we can't go
673
proc->next. Therefore, start over from the beginning of
1007
exitstatus = EXIT_FAILURE;
1011
if(plugin_list == NULL){
677
1018
/* This process exited nicely, so print its buffer */
679
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1020
bool bret = print_out_password(proc->buffer,
1021
proc->buffer_length);
681
1023
perror("print_out_password");
682
1024
exitstatus = EXIT_FAILURE;
686
1029
/* This process has not completed. Does it have any output? */
687
1030
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
688
1031
/* This process had nothing to say at this time */
691
1035
/* Before reading, make the process' data buffer large enough */
692
1036
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
693
1037
proc->buffer = realloc(proc->buffer, proc->buffer_size
694
1038
+ (size_t) BUFFER_SIZE);
695
if (proc->buffer == NULL){
1039
if(proc->buffer == NULL){
696
1040
perror("malloc");
697
1041
exitstatus = EXIT_FAILURE;
700
1044
proc->buffer_size += BUFFER_SIZE;
702
1046
/* Read from the process */
703
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1047
sret = read(proc->fd, proc->buffer + proc->buffer_length,
706
1050
/* Read error from this process; ignore the error */
711
1056
proc->eof = true;
713
proc->buffer_length += (size_t) ret;
1058
proc->buffer_length += (size_t) sret;
721
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
722
/* Fallback if all plugins failed, none are found or an error occured */
1066
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1067
/* Fallback if all plugins failed, none are found or an error
724
1070
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
725
1071
char *passwordbuffer = getpass("Password: ");
726
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1072
size_t len = strlen(passwordbuffer);
1073
/* Strip trailing newline */
1074
if(len > 0 and passwordbuffer[len-1] == '\n'){
1075
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1078
bret = print_out_password(passwordbuffer, len);
728
1080
perror("print_out_password");
729
1081
exitstatus = EXIT_FAILURE;
734
1085
/* Restore old signal handler */
735
sigaction(SIGCHLD, &old_sigchld_action, NULL);
739
/* Free the plugin list */
740
for(plugin *next; plugin_list != NULL; plugin_list = next){
741
next = plugin_list->next;
742
free(plugin_list->argv);
1086
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1088
perror("sigaction");
1089
exitstatus = EXIT_FAILURE;
1092
if(custom_argv != NULL){
1093
for(char **arg = custom_argv+1; *arg != NULL; arg++){
746
1099
if(dir != NULL){
750
/* Free the process list and kill the processes */
751
for(process *next; process_list != NULL; process_list = next){
752
next = process_list->next;
753
close(process_list->fd);
754
ret = kill(process_list->pid, SIGTERM);
755
if(ret == -1 and errno != ESRCH){
756
/* set-uid proccesses migth not get closed */
1103
/* Kill the processes */
1104
for(plugin *p = plugin_list; p != NULL; p = p->next){
1107
ret = kill(p->pid, SIGTERM);
1108
if(ret == -1 and errno != ESRCH){
1109
/* Set-uid proccesses might not get closed */
759
free(process_list->buffer);
763
1115
/* Wait for any remaining child processes to terminate */