47
46
fcntl(), setuid(), setgid(),
48
47
F_GETFD, F_SETFD, FD_CLOEXEC,
49
48
access(), pipe(), fork(), close()
50
dup2(), STDOUT_FILENO, _exit(),
49
dup2, STDOUT_FILENO, _exit(),
51
50
execv(), write(), read(),
53
52
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
#include <string.h> /* strsep, strlen(), asprintf() */
54
#include <string.h> /* strsep, strlen(), strcpy(),
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,
60
ARGP_KEY_END, ARGP_KEY_ARG, error_t */
62
61
#include <signal.h> /* struct sigaction, sigemptyset(),
63
62
sigaddset(), sigaction(),
64
63
sigprocmask(), SIG_BLOCK, SIGCHLD,
66
65
#include <errno.h> /* errno, EBADF */
68
67
#define BUFFER_SIZE 256
70
#define PDIR "/lib/mandos/plugins.d"
71
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
73
const char *argp_program_version = "plugin-runner " VERSION;
68
#define CONFFILE "/conf/conf.d/mandos/client.conf"
70
const char *argp_program_version = "mandos-client 1.0";
74
71
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
76
typedef struct plugin{
77
char *name; /* can be NULL or any plugin name */
84
/* Variables used for running processes*/
75
typedef struct process{
88
79
size_t buffer_size;
89
80
size_t buffer_length;
91
volatile bool completed;
87
typedef struct plugin{
88
char *name; /* can be NULL or any plugin name */
93
92
struct plugin *next;
96
static plugin *plugin_list = NULL;
98
/* Gets an existing plugin based on name,
99
or if none is found, creates a new one */
100
static plugin *getplugin(char *name){
101
/* Check for exiting plugin with that name */
102
for(plugin *p = plugin_list; p != NULL; p = p->next){
104
or (p->name and name and (strcmp(p->name, name) == 0))){
95
static plugin *getplugin(char *name, plugin **plugin_list){
96
for (plugin *p = *plugin_list; p != NULL; p = p->next){
98
or (p->name and name and (strcmp(p->name, name) == 0))){
108
102
/* Create a new plugin */
109
103
plugin *new_plugin = malloc(sizeof(plugin));
110
if(new_plugin == NULL){
113
char *copy_name = NULL;
115
copy_name = strdup(name);
116
if(copy_name == NULL){
121
*new_plugin = (plugin) { .name = copy_name,
124
.next = plugin_list };
104
if (new_plugin == NULL){
108
new_plugin->name = name;
126
109
new_plugin->argv = malloc(sizeof(char *) * 2);
127
if(new_plugin->argv == NULL){
110
if (new_plugin->argv == NULL){
132
new_plugin->argv[0] = copy_name;
114
new_plugin->argv[0] = name;
133
115
new_plugin->argv[1] = NULL;
135
new_plugin->environ = malloc(sizeof(char *));
136
if(new_plugin->environ == NULL){
138
free(new_plugin->argv);
142
new_plugin->environ[0] = NULL;
116
new_plugin->argc = 1;
117
new_plugin->disabled = false;
118
new_plugin->next = *plugin_list;
144
119
/* Append the new plugin to the list */
145
plugin_list = new_plugin;
120
*plugin_list = new_plugin;
146
121
return new_plugin;
149
/* Helper function for add_argument and add_environment */
150
static bool add_to_char_array(const char *new, char ***array,
152
/* Resize the pointed-to array to hold one more pointer */
153
*array = realloc(*array, sizeof(char *)
154
* (size_t) ((*len) + 2));
159
/* Make a copy of the new string */
160
char *copy = strdup(new);
164
/* Insert the copy */
165
(*array)[*len] = copy;
167
/* Add a new terminating NULL pointer to the last element */
168
(*array)[*len] = NULL;
172
/* Add to a plugin's argument vector */
173
static bool add_argument(plugin *p, const char *arg){
177
return add_to_char_array(arg, &(p->argv), &(p->argc));
180
/* Add to a plugin's environment */
181
static bool add_environment(plugin *p, const char *def, bool replace){
185
/* namelen = length of name of environment variable */
186
size_t namelen = (size_t)(strchrnul(def, '=') - def);
187
/* Search for this environment variable */
188
for(char **e = p->environ; *e != NULL; e++){
189
if(strncmp(*e, def, namelen + 1) == 0){
190
/* It already exists */
192
char *new = realloc(*e, strlen(def) + 1);
202
return add_to_char_array(def, &(p->environ), &(p->envc));
124
static void addargument(plugin *p, char *arg){
125
p->argv[p->argc] = arg;
126
p->argv = realloc(p->argv, sizeof(char *) * (size_t)(p->argc + 2));
127
if (p->argv == NULL){
132
p->argv[p->argc] = NULL;
340
246
{ .name = "global-options", .key = 'g',
341
247
.arg = "OPTION[,OPTION[,...]]",
342
248
.doc = "Options passed to all plugins" },
343
{ .name = "global-env", .key = 'G',
345
.doc = "Environment variable passed to all plugins" },
346
249
{ .name = "options-for", .key = 'o',
347
250
.arg = "PLUGIN:OPTION[,OPTION[,...]]",
348
251
.doc = "Options passed only to specified plugin" },
349
{ .name = "env-for", .key = 'E',
350
.arg = "PLUGIN:ENV=value",
351
.doc = "Environment variable passed to specified plugin" },
352
252
{ .name = "disable", .key = 'd',
354
254
.doc = "Disable a specific plugin", .group = 1 },
355
{ .name = "enable", .key = 'e',
357
.doc = "Enable a specific plugin", .group = 1 },
358
255
{ .name = "plugin-dir", .key = 128,
359
256
.arg = "DIRECTORY",
360
257
.doc = "Specify a different plugin directory", .group = 2 },
361
{ .name = "config-file", .key = 129,
363
.doc = "Specify a different configuration file", .group = 2 },
364
{ .name = "userid", .key = 130,
365
.arg = "ID", .flags = 0,
366
.doc = "User ID the plugins will run as", .group = 3 },
367
{ .name = "groupid", .key = 131,
368
.arg = "ID", .flags = 0,
369
.doc = "Group ID the plugins will run as", .group = 3 },
370
{ .name = "debug", .key = 132,
371
.doc = "Debug mode", .group = 4 },
258
{ .name = "userid", .key = 129,
259
.arg = "ID", .flags = 0,
260
.doc = "User ID the plugins will run as", .group = 2 },
261
{ .name = "groupid", .key = 130,
262
.arg = "ID", .flags = 0,
263
.doc = "Group ID the plugins will run as", .group = 2 },
264
{ .name = "debug", .key = 131,
265
.doc = "Debug mode", .group = 3 },
375
error_t parse_opt(int key, char *arg, __attribute__((unused))
376
struct argp_state *state) {
378
case 'g': /* --global-options */
269
error_t parse_opt (int key, char *arg, struct argp_state *state) {
270
/* Get the INPUT argument from `argp_parse', which we know is a
271
pointer to our plugin list pointer. */
272
plugin **plugins = state->input;
381
277
while((p = strsep(&arg, ",")) != NULL){
382
278
if(p[0] == '\0'){
385
if(not add_argument(getplugin(NULL), p)){
386
perror("add_argument");
387
return ARGP_ERR_UNKNOWN;
281
addargument(getplugin(NULL, plugins), p);
392
case 'G': /* --global-env */
396
if(not add_environment(getplugin(NULL), arg, true)){
397
perror("add_environment");
400
case 'o': /* --options-for */
402
char *p_name = strsep(&arg, ":");
403
if(p_name[0] == '\0' or arg == NULL){
287
char *name = strsep(&arg, ":");
406
291
char *opt = strsep(&arg, ":");
407
if(opt[0] == '\0' or opt == NULL){
411
while((p = strsep(&opt, ",")) != NULL){
415
if(not add_argument(getplugin(p_name), p)){
416
perror("add_argument");
417
return ARGP_ERR_UNKNOWN;
422
case 'E': /* --env-for */
427
char *envdef = strchr(arg, ':');
432
if(not add_environment(getplugin(arg), envdef+1, true)){
433
perror("add_environment");
437
case 'd': /* --disable */
439
plugin *p = getplugin(arg);
441
return ARGP_ERR_UNKNOWN;
446
case 'e': /* --enable */
448
plugin *p = getplugin(arg);
450
return ARGP_ERR_UNKNOWN;
455
case 128: /* --plugin-dir */
457
plugindir = strdup(arg);
458
if(plugindir == NULL){
462
case 129: /* --config-file */
463
/* This is already done by parse_opt_config_file() */
465
case 130: /* --userid */
466
/* In the GNU C library, uid_t is always unsigned int */
467
ret = sscanf(arg, "%u", &uid);
469
fprintf(stderr, "Bad user ID number: \"%s\", using %u\n", arg,
473
case 131: /* --groupid */
474
/* In the GNU C library, gid_t is always unsigned int */
475
ret = sscanf(arg, "%u", &gid);
477
fprintf(stderr, "Bad group ID number: \"%s\", using %u\n",
481
case 132: /* --debug */
297
while((p = strsep(&opt, ",")) != NULL){
301
addargument(getplugin(name, plugins), p);
308
getplugin(arg, plugins)->disabled = true;
315
uid = (uid_t)strtol(arg, NULL, 10);
318
gid = (gid_t)strtol(arg, NULL, 10);
485
* When adding more options before this line, remember to also add a
486
* "case" to the "parse_opt_config_file" function below.
489
/* Cryptsetup always passes an argument, which is an empty
490
string if "none" was specified in /etc/crypttab. So if
491
argument was empty, we ignore it silently. */
493
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
499
return ARGP_ERR_UNKNOWN;
504
/* This option parser is the same as parse_opt() above, except it
505
ignores everything but the --config-file option. */
506
error_t parse_opt_config_file(int key, char *arg,
507
__attribute__((unused))
508
struct argp_state *state) {
510
case 'g': /* --global-options */
511
case 'G': /* --global-env */
512
case 'o': /* --options-for */
513
case 'E': /* --env-for */
514
case 'd': /* --disable */
515
case 'e': /* --enable */
516
case 128: /* --plugin-dir */
518
case 129: /* --config-file */
520
argfile = strdup(arg);
525
case 130: /* --userid */
526
case 131: /* --groupid */
527
case 132: /* --debug */
532
return ARGP_ERR_UNKNOWN;
537
struct argp argp = { .options = options,
538
.parser = parse_opt_config_file,
324
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
329
return ARGP_ERR_UNKNOWN;
334
plugin *plugin_list = NULL;
336
struct argp argp = { .options = options, .parser = parse_opt,
337
.args_doc = "[+PLUS_SEPARATED_OPTIONS]",
540
338
.doc = "Mandos plugin runner -- Run plugins" };
542
/* Parse using parse_opt_config_file() in order to get the custom
543
config file location, if any. */
544
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
545
if(ret == ARGP_ERR_UNKNOWN){
340
ret = argp_parse (&argp, argc, argv, 0, 0, &plugin_list);
341
if (ret == ARGP_ERR_UNKNOWN){
546
342
fprintf(stderr, "Unknown error while parsing arguments\n");
547
343
exitstatus = EXIT_FAILURE;
551
/* Reset to the normal argument parser */
552
argp.parser = parse_opt;
554
/* Open the configfile if available */
556
conffp = fopen(AFILE, "r");
558
conffp = fopen(argfile, "r");
347
conffp = fopen(conffile, "r");
560
348
if(conffp != NULL){
561
349
char *org_line = NULL;
562
352
char *p, *arg, *new_arg, *line;
564
353
const char whitespace_delims[] = " \r\t\f\v\n";
565
354
const char comment_delim[] = "#";
568
custom_argv = malloc(sizeof(char*) * 2);
569
if(custom_argv == NULL){
571
exitstatus = EXIT_FAILURE;
574
custom_argv[0] = argv[0];
575
custom_argv[1] = NULL;
577
/* for each line in the config file, strip whitespace and ignore
580
357
sret = getline(&org_line, &size, conffp);
591
368
new_arg = strdup(p);
594
exitstatus = EXIT_FAILURE;
600
custom_argv = realloc(custom_argv, sizeof(char *)
601
* ((unsigned int) custom_argc + 1));
602
if(custom_argv == NULL){
604
exitstatus = EXIT_FAILURE;
608
custom_argv[custom_argc-1] = new_arg;
609
custom_argv[custom_argc] = NULL;
369
custom_argv = addcustomargument(custom_argv, &custom_argc, new_arg);
370
if (custom_argv == NULL){
371
perror("addcustomargument");
372
exitstatus = EXIT_FAILURE;
614
/* Check for harmful errors and go to fallback. Other errors might
615
not affect opening plugins */
616
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
379
/* check for harmfull errors */
380
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
618
382
exitstatus = EXIT_FAILURE;
622
/* If there was any arguments from configuration file,
623
pass them to parser as command arguments */
624
387
if(custom_argv != NULL){
625
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
627
if(ret == ARGP_ERR_UNKNOWN){
388
custom_argv[0] = argv[0];
389
ret = argp_parse (&argp, custom_argc, custom_argv, 0, 0, &plugin_list);
390
if (ret == ARGP_ERR_UNKNOWN){
628
391
fprintf(stderr, "Unknown error while parsing arguments\n");
629
392
exitstatus = EXIT_FAILURE;
634
/* Parse actual command line arguments, to let them override the
636
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
637
if(ret == ARGP_ERR_UNKNOWN){
638
fprintf(stderr, "Unknown error while parsing arguments\n");
639
exitstatus = EXIT_FAILURE;
644
398
for(plugin *p = plugin_list; p != NULL; p=p->next){
645
399
fprintf(stderr, "Plugin: %s has %d arguments\n",
531
plugin *p = getplugin(dirst->d_name, &plugin_list);
797
533
/* Add global arguments to argument list for this plugin */
798
plugin *g = getplugin(NULL);
800
for(char **a = g->argv + 1; *a != NULL; a++){
801
if(not add_argument(p, *a)){
802
perror("add_argument");
805
/* Add global environment variables */
806
for(char **e = g->environ; *e != NULL; e++){
807
if(not add_environment(p, *e, false)){
808
perror("add_environment");
813
/* If this plugin has any environment variables, we will call
814
using execve and need to duplicate the environment from this
816
if(p->environ[0] != NULL){
817
for(char **e = environ; *e != NULL; e++){
818
if(not add_environment(p, *e, false)){
819
perror("add_environment");
534
plugin *g = getplugin(NULL, &plugin_list);
535
for(char **a = g->argv + 1; *a != NULL; a++){
825
540
ret = pipe(pipefd);
828
543
exitstatus = EXIT_FAILURE;
831
/* Ask OS to automatic close the pipe on exec */
832
546
ret = set_cloexec_flag(pipefd[0]);
834
548
perror("set_cloexec_flag");
835
549
exitstatus = EXIT_FAILURE;
838
552
ret = set_cloexec_flag(pipefd[1]);
840
554
perror("set_cloexec_flag");
841
555
exitstatus = EXIT_FAILURE;
844
558
/* Block SIGCHLD until process is safely in process list */
845
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
559
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
847
561
perror("sigprocmask");
848
562
exitstatus = EXIT_FAILURE;
851
/* Starting a new process to be watched */
565
// Starting a new process to be watched
852
566
pid_t pid = fork();
855
569
exitstatus = EXIT_FAILURE;
859
573
/* this is the child process */
879
593
above and must now close it manually here. */
882
if(p->environ[0] == NULL){
883
if(execv(filename, p->argv) < 0){
888
if(execve(filename, p->argv, p->environ) < 0){
596
if(execv(filename, p->argv) < 0){
896
close(pipefd[1]); /* Close unused write end of pipe */
898
plugin *new_plugin = getplugin(dirst->d_name);
899
if(new_plugin == NULL){
901
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
604
close(pipefd[1]); /* close unused write end of pipe */
605
process *new_process = malloc(sizeof(process));
606
if (new_process == NULL){
608
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
903
perror("sigprocmask");
610
perror("sigprocmask");
905
612
exitstatus = EXIT_FAILURE;
909
new_plugin->pid = pid;
910
new_plugin->fd = pipefd[0];
616
*new_process = (struct process){ .pid = pid,
618
.next = process_list };
620
process_list = new_process;
912
621
/* Unblock SIGCHLD so signal handler can be run if this process
913
622
has already completed */
914
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
623
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
916
625
perror("sigprocmask");
917
626
exitstatus = EXIT_FAILURE;
921
FD_SET(new_plugin->fd, &rfds_all);
923
if(maxfd < new_plugin->fd){
924
maxfd = new_plugin->fd;
630
FD_SET(new_process->fd, &rfds_all);
632
if (maxfd < new_process->fd){
633
maxfd = new_process->fd;
638
/* Free the plugin list */
639
for(plugin *next; plugin_list != NULL; plugin_list = next){
640
next = plugin_list->next;
641
free(plugin_list->argv);
931
for(plugin *p = plugin_list; p != NULL; p = p->next){
936
fprintf(stderr, "No plugin processes started. Incorrect plugin"
648
if (process_list == NULL){
649
fprintf(stderr, "No plugin processes started. Incorrect plugin"
942
/* Main loop while running plugins exist */
944
654
fd_set rfds = rfds_all;
945
655
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
946
if(select_ret == -1){
656
if (select_ret == -1){
947
657
perror("select");
948
658
exitstatus = EXIT_FAILURE;
951
661
/* OK, now either a process completed, or something can be read
952
662
from one of them */
953
for(plugin *proc = plugin_list; proc != NULL;){
663
for(process *proc = process_list; proc ; proc = proc->next){
954
664
/* Is this process completely done? */
955
665
if(proc->eof and proc->completed){
956
666
/* Only accept the plugin output if it exited cleanly */
957
667
if(not WIFEXITED(proc->status)
958
668
or WEXITSTATUS(proc->status) != 0){
959
669
/* Bad exit by plugin */
962
671
if(WIFEXITED(proc->status)){
963
672
fprintf(stderr, "Plugin %u exited with status %d\n",
968
677
(unsigned int) (proc->pid),
969
678
WTERMSIG(proc->status));
970
679
} else if(WCOREDUMP(proc->status)){
971
fprintf(stderr, "Plugin %u dumped core\n",
680
fprintf(stderr, "Plugin %d dumped core\n",
972
681
(unsigned int) (proc->pid));
976
684
/* Remove the plugin */
977
685
FD_CLR(proc->fd, &rfds_all);
979
686
/* Block signal while modifying process_list */
980
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
687
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
982
689
perror("sigprocmask");
983
690
exitstatus = EXIT_FAILURE;
987
plugin *next_plugin = proc->next;
693
/* Delete this process entry from the list */
694
if(process_list == proc){
695
/* First one - simple */
696
process_list = proc->next;
698
/* Second one or later */
699
for(process *p = process_list; p != NULL; p = p->next){
701
p->next = proc->next;
991
706
/* We are done modifying process list, so unblock signal */
992
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
707
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
995
710
perror("sigprocmask");
996
exitstatus = EXIT_FAILURE;
1000
if(plugin_list == NULL){
714
/* We deleted this process from the list, so we can't go
715
proc->next. Therefore, start over from the beginning of
1007
719
/* This process exited nicely, so print its buffer */
1009
bool bret = print_out_password(proc->buffer,
1010
proc->buffer_length);
721
bool bret = print_out_password(proc->buffer, proc->buffer_length);
1012
723
perror("print_out_password");
1013
724
exitstatus = EXIT_FAILURE;
1018
728
/* This process has not completed. Does it have any output? */
1019
729
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1020
730
/* This process had nothing to say at this time */
1024
733
/* Before reading, make the process' data buffer large enough */
1025
734
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1026
735
proc->buffer = realloc(proc->buffer, proc->buffer_size
1027
736
+ (size_t) BUFFER_SIZE);
1028
if(proc->buffer == NULL){
737
if (proc->buffer == NULL){
1029
738
perror("malloc");
1030
739
exitstatus = EXIT_FAILURE;
1033
742
proc->buffer_size += BUFFER_SIZE;
1035
744
/* Read from the process */
1036
sret = read(proc->fd, proc->buffer + proc->buffer_length,
745
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1039
748
/* Read error from this process; ignore the error */
1045
753
proc->eof = true;
1047
proc->buffer_length += (size_t) sret;
755
proc->buffer_length += (size_t) ret;
1055
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1056
/* Fallback if all plugins failed, none are found or an error
763
if(process_list == NULL or exitstatus != EXIT_SUCCESS){
764
/* Fallback if all plugins failed, none are found or an error occured */
1059
766
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1060
767
char *passwordbuffer = getpass("Password: ");
1061
size_t len = strlen(passwordbuffer);
1062
/* Strip trailing newline */
1063
if(len > 0 and passwordbuffer[len-1] == '\n'){
1064
passwordbuffer[len-1] = '\0'; /* not strictly necessary */
1067
bret = print_out_password(passwordbuffer, len);
768
bret = print_out_password(passwordbuffer, strlen(passwordbuffer));
1069
770
perror("print_out_password");
1070
771
exitstatus = EXIT_FAILURE;
1074
776
/* Restore old signal handler */
1075
ret = sigaction(SIGCHLD, &old_sigchld_action, NULL);
1077
perror("sigaction");
1078
exitstatus = EXIT_FAILURE;
1081
if(custom_argv != NULL){
1082
for(char **arg = custom_argv+1; *arg != NULL; arg++){
777
sigaction(SIGCHLD, &old_sigchld_action, NULL);
781
/* Free the plugin list */
782
for(plugin *next; plugin_list != NULL; plugin_list = next){
783
next = plugin_list->next;
784
free(plugin_list->argv);
1088
788
if(dir != NULL){
1092
/* Kill the processes */
1093
for(plugin *p = plugin_list; p != NULL; p = p->next){
1096
ret = kill(p->pid, SIGTERM);
1097
if(ret == -1 and errno != ESRCH){
1098
/* Set-uid proccesses might not get closed */
792
/* Free the process list and kill the processes */
793
for(process *next; process_list != NULL; process_list = next){
794
next = process_list->next;
795
close(process_list->fd);
796
ret = kill(process_list->pid, SIGTERM);
797
if(ret == -1 and errno != ESRCH){
798
/* set-uid proccesses migth not get closed */
801
free(process_list->buffer);
1104
805
/* Wait for any remaining child processes to terminate */