3
3
* Mandos plugin runner - Run Mandos plugins
5
* Copyright © 2007-2008 Teddy Hogeborn & Björn Påhlsson
5
* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
7
8
* This program is free software: you can redistribute it and/or
8
9
* modify it under the terms of the GNU General Public License as
27
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
29
EXIT_SUCCESS, realloc() */
29
30
#include <stdbool.h> /* bool, true, false */
30
#include <stdio.h> /* perror, popen(), fileno(),
31
fprintf(), stderr, STDOUT_FILENO */
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
32
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
34
stat, waitpid(), WIFEXITED(),
34
35
WEXITSTATUS(), wait(), pid_t,
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,
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
71
#define PDIR "/lib/mandos/plugins.d"
70
72
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
const char *argp_program_version = "plugin-runner 1.0";
74
const char *argp_program_version = "plugin-runner " VERSION;
73
75
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
77
77
typedef struct plugin{
78
78
char *name; /* can be NULL or any plugin name */
97
97
static plugin *plugin_list = NULL;
99
/* Gets a existing plugin based on name,
99
/* Gets an existing plugin based on name,
100
100
or if none is found, creates a new one */
101
101
static plugin *getplugin(char *name){
102
102
/* Check for exiting plugin with that name */
103
for (plugin *p = plugin_list; p != NULL; p = p->next){
104
if ((p->name == name)
105
or (p->name and name and (strcmp(p->name, name) == 0))){
103
for(plugin *p = plugin_list; p != NULL; p = p->next){
105
or (p->name and name and (strcmp(p->name, name) == 0))){
109
109
/* Create a new plugin */
110
110
plugin *new_plugin = malloc(sizeof(plugin));
111
if (new_plugin == NULL){
111
if(new_plugin == NULL){
114
114
char *copy_name = NULL;
122
122
*new_plugin = (plugin) { .name = copy_name,
124
124
.disabled = false,
125
125
.next = plugin_list };
127
127
new_plugin->argv = malloc(sizeof(char *) * 2);
128
if (new_plugin->argv == NULL){
128
if(new_plugin->argv == NULL){
130
130
free(new_plugin);
187
187
size_t namelen = (size_t)(strchrnul(def, '=') - def);
188
188
/* Search for this environment variable */
189
189
for(char **e = p->environ; *e != NULL; e++){
190
if(strncmp(*e, def, namelen+1) == 0){
190
if(strncmp(*e, def, namelen + 1) == 0){
191
191
/* It already exists */
193
char *new = realloc(*e, strlen(def));
193
char *new = realloc(*e, strlen(def) + 1);
208
208
* Descriptor Flags".
209
209
* *Note File Descriptor Flags:(libc)Descriptor Flags.
211
static int set_cloexec_flag(int fd)
211
static int set_cloexec_flag(int fd){
213
212
int ret = fcntl(fd, F_GETFD, 0);
214
213
/* If reading the flags failed, return error indication now. */
223
222
/* Mark processes as completed when they exit, and save their exit
225
void handle_sigchld(__attribute__((unused)) int sig){
224
static void handle_sigchld(__attribute__((unused)) int sig){
227
226
plugin *proc = plugin_list;
255
254
/* Prints out a password to stdout */
256
bool print_out_password(const char *buffer, size_t length){
255
static bool print_out_password(const char *buffer, size_t length){
258
if(length>0 and buffer[length-1] == '\n'){
261
257
for(size_t written = 0; written < length; written += (size_t)ret){
262
258
ret = TEMP_FAILURE_RETRY(write(STDOUT_FILENO, buffer + written,
263
259
length - written));
379
error_t parse_opt (int key, char *arg, __attribute__((unused))
380
struct argp_state *state) {
377
error_t parse_opt(int key, char *arg, __attribute__((unused))
378
struct argp_state *state) {
382
380
case 'g': /* --global-options */
385
383
while((p = strsep(&arg, ",")) != NULL){
386
384
if(p[0] == '\0'){
401
char *envdef = strdup(arg);
405
if(not add_environment(getplugin(NULL), envdef, true)){
406
perror("add_environment");
398
if(not add_environment(getplugin(NULL), arg, true)){
399
perror("add_environment");
410
402
case 'o': /* --options-for */
412
404
char *p_name = strsep(&arg, ":");
413
if(p_name[0] == '\0'){
405
if(p_name[0] == '\0' or arg == NULL){
416
408
char *opt = strsep(&arg, ":");
409
if(opt[0] == '\0' or opt == NULL){
422
while((p = strsep(&opt, ",")) != NULL){
426
if(not add_argument(getplugin(p_name), p)){
427
perror("add_argument");
428
return ARGP_ERR_UNKNOWN;
413
while((p = strsep(&opt, ",")) != NULL){
417
if(not add_argument(getplugin(p_name), p)){
418
perror("add_argument");
419
return ARGP_ERR_UNKNOWN;
440
430
if(envdef == NULL){
443
char *p_name = strndup(arg, (size_t) (envdef-arg));
448
if(not add_environment(getplugin(p_name), envdef, true)){
434
if(not add_environment(getplugin(arg), envdef+1, true)){
449
435
perror("add_environment");
453
439
case 'd': /* --disable */
455
441
plugin *p = getplugin(arg);
457
443
return ARGP_ERR_UNKNOWN;
478
465
/* This is already done by parse_opt_config_file() */
480
467
case 130: /* --userid */
481
uid = (uid_t)strtol(arg, NULL, 10);
468
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
469
if(ret < 1 or tmpmax != (uid_t)tmpmax
470
or arg[numchars] != '\0'){
471
fprintf(stderr, "Bad user ID number: \"%s\", using %"
472
PRIdMAX "\n", arg, (intmax_t)uid);
483
477
case 131: /* --groupid */
484
gid = (gid_t)strtol(arg, NULL, 10);
478
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
479
if(ret < 1 or tmpmax != (gid_t)tmpmax
480
or arg[numchars] != '\0'){
481
fprintf(stderr, "Bad group ID number: \"%s\", using %"
482
PRIdMAX "\n", arg, (intmax_t)gid);
486
487
case 132: /* --debug */
491
* When adding more options before this line, remember to also add a
492
* "case" to the "parse_opt_config_file" function below.
489
494
case ARGP_KEY_ARG:
490
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
495
/* Cryptsetup always passes an argument, which is an empty
496
string if "none" was specified in /etc/crypttab. So if
497
argument was empty, we ignore it silently. */
499
fprintf(stderr, "Ignoring unknown argument \"%s\"\n", arg);
492
502
case ARGP_KEY_END:
500
510
/* This option parser is the same as parse_opt() above, except it
501
511
ignores everything but the --config-file option. */
502
error_t parse_opt_config_file (int key, char *arg,
503
__attribute__((unused))
504
struct argp_state *state) {
512
error_t parse_opt_config_file(int key, char *arg,
513
__attribute__((unused))
514
struct argp_state *state) {
506
516
case 'g': /* --global-options */
507
517
case 'G': /* --global-env */
508
518
case 'o': /* --options-for */
535
546
.doc = "Mandos plugin runner -- Run plugins" };
537
/* Parse using the parse_opt_config_file in order to get the custom
548
/* Parse using parse_opt_config_file() in order to get the custom
538
549
config file location, if any. */
539
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
540
if (ret == ARGP_ERR_UNKNOWN){
550
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
551
if(ret == ARGP_ERR_UNKNOWN){
541
552
fprintf(stderr, "Unknown error while parsing arguments\n");
542
553
exitstatus = EXIT_FAILURE;
556
567
char *org_line = NULL;
557
568
char *p, *arg, *new_arg, *line;
560
570
const char whitespace_delims[] = " \r\t\f\v\n";
561
571
const char comment_delim[] = "#";
610
620
/* Check for harmful errors and go to fallback. Other errors might
611
621
not affect opening plugins */
612
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
622
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
614
624
exitstatus = EXIT_FAILURE;
618
628
/* If there was any arguments from configuration file,
619
629
pass them to parser as command arguments */
620
630
if(custom_argv != NULL){
621
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
623
if (ret == ARGP_ERR_UNKNOWN){
631
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
633
if(ret == ARGP_ERR_UNKNOWN){
624
634
fprintf(stderr, "Unknown error while parsing arguments\n");
625
635
exitstatus = EXIT_FAILURE;
630
640
/* Parse actual command line arguments, to let them override the
632
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
633
if (ret == ARGP_ERR_UNKNOWN){
642
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
643
if(ret == ARGP_ERR_UNKNOWN){
634
644
fprintf(stderr, "Unknown error while parsing arguments\n");
635
645
exitstatus = EXIT_FAILURE;
643
653
for(char **a = p->argv; *a != NULL; a++){
644
654
fprintf(stderr, "\tArg: %s\n", *a);
646
fprintf(stderr, "...and %u environment variables\n", p->envc);
656
fprintf(stderr, "...and %d environment variables\n", p->envc);
647
657
for(char **a = p->environ; *a != NULL; a++){
648
658
fprintf(stderr, "\t%s\n", *a);
712
722
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
714
725
".dpkg-divert", NULL };
715
726
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
716
727
size_t pre_len = strlen(*pre);
750
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
761
if(plugindir == NULL){
762
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
764
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
752
767
perror("asprintf");
756
771
ret = stat(filename, &st);
763
778
/* Ignore non-executable files */
764
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
779
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
766
781
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
767
782
" with bad type or mode\n", filename);
835
850
/* Block SIGCHLD until process is safely in process list */
836
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
851
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
838
853
perror("sigprocmask");
839
854
exitstatus = EXIT_FAILURE;
853
868
perror("sigaction");
854
869
_exit(EXIT_FAILURE);
856
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
871
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
858
873
perror("sigprocmask");
859
874
_exit(EXIT_FAILURE);
862
877
ret = dup2(pipefd[1], STDOUT_FILENO); /* replace our stdout */
887
902
close(pipefd[1]); /* Close unused write end of pipe */
889
904
plugin *new_plugin = getplugin(dirst->d_name);
890
if (new_plugin == NULL){
905
if(new_plugin == NULL){
891
906
perror("getplugin");
892
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
894
909
perror("sigprocmask");
903
918
/* Unblock SIGCHLD so signal handler can be run if this process
904
919
has already completed */
905
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
907
922
perror("sigprocmask");
908
923
exitstatus = EXIT_FAILURE;
912
927
FD_SET(new_plugin->fd, &rfds_all);
914
if (maxfd < new_plugin->fd){
929
if(maxfd < new_plugin->fd){
915
930
maxfd = new_plugin->fd;
923
937
for(plugin *p = plugin_list; p != NULL; p = p->next){
930
944
free_plugin_list();
934
948
/* Main loop while running plugins exist */
935
949
while(plugin_list){
936
950
fd_set rfds = rfds_all;
937
951
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
938
if (select_ret == -1){
952
if(select_ret == -1){
939
953
perror("select");
940
954
exitstatus = EXIT_FAILURE;
943
957
/* OK, now either a process completed, or something can be read
944
958
from one of them */
945
for(plugin *proc = plugin_list; proc != NULL; proc = proc->next){
959
for(plugin *proc = plugin_list; proc != NULL;){
946
960
/* Is this process completely done? */
947
961
if(proc->eof and proc->completed){
948
962
/* Only accept the plugin output if it exited cleanly */
954
968
if(WIFEXITED(proc->status)){
955
fprintf(stderr, "Plugin %u exited with status %d\n",
956
(unsigned int) (proc->pid),
969
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
970
" %d\n", (intmax_t) (proc->pid),
957
971
WEXITSTATUS(proc->status));
958
972
} else if(WIFSIGNALED(proc->status)) {
959
fprintf(stderr, "Plugin %u killed by signal %d\n",
960
(unsigned int) (proc->pid),
973
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
974
" %d\n", (intmax_t) (proc->pid),
961
975
WTERMSIG(proc->status));
962
976
} else if(WCOREDUMP(proc->status)){
963
fprintf(stderr, "Plugin %d dumped core\n",
964
(unsigned int) (proc->pid));
977
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
978
(intmax_t) (proc->pid));
975
989
exitstatus = EXIT_FAILURE;
993
plugin *next_plugin = proc->next;
978
994
free_plugin(proc);
979
997
/* We are done modifying process list, so unblock signal */
980
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
998
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
983
1001
perror("sigprocmask");
984
1002
exitstatus = EXIT_FAILURE;
1005
1024
/* This process has not completed. Does it have any output? */
1006
1025
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1007
1026
/* This process had nothing to say at this time */
1010
1030
/* Before reading, make the process' data buffer large enough */
1011
1031
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1012
1032
proc->buffer = realloc(proc->buffer, proc->buffer_size
1013
1033
+ (size_t) BUFFER_SIZE);
1014
if (proc->buffer == NULL){
1034
if(proc->buffer == NULL){
1015
1035
perror("malloc");
1016
1036
exitstatus = EXIT_FAILURE;
1019
1039
proc->buffer_size += BUFFER_SIZE;
1021
1041
/* Read from the process */
1022
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1042
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1025
1045
/* Read error from this process; ignore the error */
1030
1051
proc->eof = true;
1032
proc->buffer_length += (size_t) ret;
1053
proc->buffer_length += (size_t) sret;
1044
1065
fprintf(stderr, "Going to fallback mode using getpass(3)\n");
1045
1066
char *passwordbuffer = getpass("Password: ");
1046
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);
1048
1075
perror("print_out_password");
1049
1076
exitstatus = EXIT_FAILURE;