1
/* -*- coding: utf-8 -*- */
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
3
3
* Mandos plugin runner - Run Mandos plugins
5
* Copyright © 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
24
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
26
27
#include <stddef.h> /* size_t, NULL */
27
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
28
29
EXIT_SUCCESS, realloc() */
29
30
#include <stdbool.h> /* bool, true, false */
30
31
#include <stdio.h> /* perror, fileno(), fprintf(),
31
32
stderr, STDOUT_FILENO */
32
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
33
34
stat, waitpid(), WIFEXITED(),
34
35
WEXITSTATUS(), wait(), pid_t,
35
36
uid_t, gid_t, getuid(), getgid(),
37
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
39
FD_SET(), FD_ISSET(), FD_CLR */
39
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
41
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
42
44
#include <iso646.h> /* and, or, not */
43
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
44
46
readdir(), closedir(), dirfd() */
45
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
46
48
fcntl(), setuid(), setgid(),
52
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
55
58
#include <errno.h> /* errno */
56
59
#include <argp.h> /* struct argp_option, struct
57
60
argp_state, struct argp,
61
64
#include <signal.h> /* struct sigaction, sigemptyset(),
62
65
sigaddset(), sigaction(),
63
66
sigprocmask(), SIG_BLOCK, SIGCHLD,
64
SIG_UNBLOCK, kill() */
67
SIG_UNBLOCK, kill(), sig_atomic_t
65
69
#include <errno.h> /* errno, EBADF */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
67
72
#define BUFFER_SIZE 256
69
74
#define PDIR "/lib/mandos/plugins.d"
70
75
#define AFILE "/conf/conf.d/mandos/plugin-runner.conf"
72
const char *argp_program_version = "plugin-runner 1.0";
77
const char *argp_program_version = "plugin-runner " VERSION;
73
78
const char *argp_program_bug_address = "<mandos@fukt.bsnet.se>";
75
80
typedef struct plugin{
98
103
or if none is found, creates a new one */
99
104
static plugin *getplugin(char *name){
100
105
/* Check for exiting plugin with that name */
101
for (plugin *p = plugin_list; p != NULL; p = p->next){
102
if ((p->name == name)
103
or (p->name and name and (strcmp(p->name, name) == 0))){
106
for(plugin *p = plugin_list; p != NULL; p = p->next){
108
or (p->name and name and (strcmp(p->name, name) == 0))){
107
112
/* Create a new plugin */
108
plugin *new_plugin = malloc(sizeof(plugin));
109
if (new_plugin == NULL){
113
plugin *new_plugin = NULL;
115
new_plugin = malloc(sizeof(plugin));
116
} while(new_plugin == NULL and errno == EINTR);
117
if(new_plugin == NULL){
112
120
char *copy_name = NULL;
113
121
if(name != NULL){
114
copy_name = strdup(name);
123
copy_name = strdup(name);
124
} while(copy_name == NULL and errno == EINTR);
115
125
if(copy_name == NULL){
120
*new_plugin = (plugin) { .name = copy_name,
123
.next = plugin_list };
131
*new_plugin = (plugin){ .name = copy_name,
134
.next = plugin_list };
125
new_plugin->argv = malloc(sizeof(char *) * 2);
126
if (new_plugin->argv == NULL){
137
new_plugin->argv = malloc(sizeof(char *) * 2);
138
} while(new_plugin->argv == NULL and errno == EINTR);
139
if(new_plugin->argv == NULL){
128
141
free(new_plugin);
149
164
static bool add_to_char_array(const char *new, char ***array,
151
166
/* Resize the pointed-to array to hold one more pointer */
152
*array = realloc(*array, sizeof(char *)
153
* (size_t) ((*len) + 2));
168
*array = realloc(*array, sizeof(char *)
169
* (size_t) ((*len) + 2));
170
} while(*array == NULL and errno == EINTR);
154
171
/* Malloc check */
155
172
if(*array == NULL){
158
175
/* Make a copy of the new string */
159
char *copy = strdup(new);
179
} while(copy == NULL and errno == EINTR);
160
180
if(copy == NULL){
205
228
* Based on the example in the GNU LibC manual chapter 13.13 "File
206
229
* Descriptor Flags".
207
* *Note File Descriptor Flags:(libc)Descriptor Flags.
230
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
209
232
static int set_cloexec_flag(int fd){
210
int ret = fcntl(fd, F_GETFD, 0);
233
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
211
234
/* If reading the flags failed, return error indication now. */
215
238
/* Store modified flag word in the descriptor. */
216
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
239
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
220
244
/* Mark processes as completed when they exit, and save their exit
222
246
static void handle_sigchld(__attribute__((unused)) int sig){
247
int old_errno = errno;
224
249
plugin *proc = plugin_list;
373
error_t parse_opt (int key, char *arg, __attribute__((unused))
374
struct argp_state *state) {
400
error_t parse_opt(int key, char *arg, __attribute__((unused))
401
struct argp_state *state){
376
405
case 'g': /* --global-options */
379
while((p = strsep(&arg, ",")) != NULL){
408
while((plugin_option = strsep(&arg, ",")) != NULL){
409
if(plugin_option[0] == '\0'){
383
if(not add_argument(getplugin(NULL), p)){
412
if(not add_argument(getplugin(NULL), plugin_option)){
384
413
perror("add_argument");
385
414
return ARGP_ERR_UNKNOWN;
398
427
case 'o': /* --options-for */
400
char *p_name = strsep(&arg, ":");
401
if(p_name[0] == '\0' or arg == NULL){
404
char *opt = strsep(&arg, ":");
405
if(opt[0] == '\0' or opt == NULL){
409
while((p = strsep(&opt, ",")) != NULL){
413
if(not add_argument(getplugin(p_name), p)){
429
char *plugin_name = strsep(&arg, ":");
430
if(plugin_name[0] == '\0'){
434
while((plugin_option = strsep(&arg, ",")) != NULL){
435
if(not add_argument(getplugin(plugin_name), plugin_option)){
414
436
perror("add_argument");
415
437
return ARGP_ERR_UNKNOWN;
455
477
plugindir = strdup(arg);
456
478
if(plugindir == NULL){
457
479
perror("strdup");
460
482
case 129: /* --config-file */
461
483
/* This is already done by parse_opt_config_file() */
463
485
case 130: /* --userid */
464
uid = (uid_t)strtol(arg, NULL, 10);
487
tmpmax = strtoimax(arg, &tmp, 10);
488
if(errno != 0 or tmp == arg or *tmp != '\0'
489
or tmpmax != (uid_t)tmpmax){
490
fprintf(stderr, "Bad user ID number: \"%s\", using %"
491
PRIdMAX "\n", arg, (intmax_t)uid);
466
496
case 131: /* --groupid */
467
gid = (gid_t)strtol(arg, NULL, 10);
498
tmpmax = strtoimax(arg, &tmp, 10);
499
if(errno != 0 or tmp == arg or *tmp != '\0'
500
or tmpmax != (gid_t)tmpmax){
501
fprintf(stderr, "Bad group ID number: \"%s\", using %"
502
PRIdMAX "\n", arg, (intmax_t)gid);
469
507
case 132: /* --debug */
511
* When adding more options before this line, remember to also add a
512
* "case" to the "parse_opt_config_file" function below.
472
514
case ARGP_KEY_ARG:
473
515
/* Cryptsetup always passes an argument, which is an empty
474
516
string if "none" was specified in /etc/crypttab. So if
488
530
/* This option parser is the same as parse_opt() above, except it
489
531
ignores everything but the --config-file option. */
490
error_t parse_opt_config_file (int key, char *arg,
491
__attribute__((unused))
492
struct argp_state *state) {
532
error_t parse_opt_config_file(int key, char *arg,
533
__attribute__((unused))
534
struct argp_state *state){
494
536
case 'g': /* --global-options */
495
537
case 'G': /* --global-env */
496
538
case 'o': /* --options-for */
524
566
.doc = "Mandos plugin runner -- Run plugins" };
526
/* Parse using the parse_opt_config_file in order to get the custom
568
/* Parse using parse_opt_config_file() in order to get the custom
527
569
config file location, if any. */
528
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
529
if (ret == ARGP_ERR_UNKNOWN){
570
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
571
if(ret == ARGP_ERR_UNKNOWN){
530
572
fprintf(stderr, "Unknown error while parsing arguments\n");
531
573
exitstatus = EXIT_FAILURE;
536
578
argp.parser = parse_opt;
538
580
/* Open the configfile if available */
539
if (argfile == NULL){
540
582
conffp = fopen(AFILE, "r");
542
584
conffp = fopen(argfile, "r");
544
586
if(conffp != NULL){
545
587
char *org_line = NULL;
546
588
char *p, *arg, *new_arg, *line;
549
590
const char whitespace_delims[] = " \r\t\f\v\n";
550
591
const char comment_delim[] = "#";
553
594
custom_argv = malloc(sizeof(char*) * 2);
554
595
if(custom_argv == NULL){
593
634
custom_argv[custom_argc-1] = new_arg;
594
custom_argv[custom_argc] = NULL;
635
custom_argv[custom_argc] = NULL;
639
ret = fclose(conffp);
640
} while(ret == EOF and errno == EINTR);
643
exitstatus = EXIT_FAILURE;
599
648
/* Check for harmful errors and go to fallback. Other errors might
600
649
not affect opening plugins */
601
if (errno == EMFILE or errno == ENFILE or errno == ENOMEM){
650
if(errno == EMFILE or errno == ENFILE or errno == ENOMEM){
603
652
exitstatus = EXIT_FAILURE;
607
656
/* If there was any arguments from configuration file,
608
657
pass them to parser as command arguments */
609
658
if(custom_argv != NULL){
610
ret = argp_parse (&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
612
if (ret == ARGP_ERR_UNKNOWN){
659
ret = argp_parse(&argp, custom_argc, custom_argv, ARGP_IN_ORDER,
661
if(ret == ARGP_ERR_UNKNOWN){
613
662
fprintf(stderr, "Unknown error while parsing arguments\n");
614
663
exitstatus = EXIT_FAILURE;
619
668
/* Parse actual command line arguments, to let them override the
621
ret = argp_parse (&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
622
if (ret == ARGP_ERR_UNKNOWN){
670
ret = argp_parse(&argp, argc, argv, ARGP_IN_ORDER, 0, NULL);
671
if(ret == ARGP_ERR_UNKNOWN){
623
672
fprintf(stderr, "Unknown error while parsing arguments\n");
624
673
exitstatus = EXIT_FAILURE;
632
681
for(char **a = p->argv; *a != NULL; a++){
633
682
fprintf(stderr, "\tArg: %s\n", *a);
635
fprintf(stderr, "...and %u environment variables\n", p->envc);
684
fprintf(stderr, "...and %d environment variables\n", p->envc);
636
685
for(char **a = p->environ; *a != NULL; a++){
637
686
fprintf(stderr, "\t%s\n", *a);
642
691
/* Strip permissions down to nobody */
643
696
ret = setuid(uid);
645
698
perror("setuid");
652
if (plugindir == NULL){
655
dir = opendir(plugindir);
659
perror("Could not open plugin dir");
660
exitstatus = EXIT_FAILURE;
664
/* Set the FD_CLOEXEC flag on the directory, if possible */
701
/* Open plugin directory with close_on_exec flag */
666
int dir_fd = dirfd(dir);
668
ret = set_cloexec_flag(dir_fd);
670
perror("set_cloexec_flag");
671
exitstatus = EXIT_FAILURE;
704
if(plugindir == NULL){
705
dir_fd = open(PDIR, O_RDONLY |
708
#else /* not O_CLOEXEC */
710
#endif /* not O_CLOEXEC */
713
dir_fd = open(plugindir, O_RDONLY |
716
#else /* not O_CLOEXEC */
718
#endif /* not O_CLOEXEC */
722
perror("Could not open plugin dir");
723
exitstatus = EXIT_FAILURE;
728
/* Set the FD_CLOEXEC flag on the directory */
729
ret = set_cloexec_flag(dir_fd);
731
perror("set_cloexec_flag");
732
TEMP_FAILURE_RETRY(close(dir_fd));
733
exitstatus = EXIT_FAILURE;
736
#endif /* O_CLOEXEC */
738
dir = fdopendir(dir_fd);
740
perror("Could not open plugin dir");
741
TEMP_FAILURE_RETRY(close(dir_fd));
742
exitstatus = EXIT_FAILURE;
739
812
if(plugindir == NULL){
740
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
813
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
742
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
816
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
745
821
perror("asprintf");
749
ret = stat(filename, &st);
825
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
756
832
/* Ignore non-executable files */
757
if (not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
833
if(not S_ISREG(st.st_mode)
834
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
759
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
760
837
" with bad type or mode\n", filename);
828
905
/* Block SIGCHLD until process is safely in process list */
829
ret = sigprocmask (SIG_BLOCK, &sigchld_action.sa_mask, NULL);
906
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
907
&sigchld_action.sa_mask,
831
910
perror("sigprocmask");
832
911
exitstatus = EXIT_FAILURE;
835
914
/* Starting a new process to be watched */
918
} while(pid == -1 and errno == EINTR);
839
921
exitstatus = EXIT_FAILURE;
879
961
/* Parent process */
880
close(pipefd[1]); /* Close unused write end of pipe */
962
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
882
965
plugin *new_plugin = getplugin(dirst->d_name);
883
if (new_plugin == NULL){
966
if(new_plugin == NULL){
884
967
perror("getplugin");
885
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
968
ret = (int)(TEMP_FAILURE_RETRY
969
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
887
972
perror("sigprocmask");
896
981
/* Unblock SIGCHLD so signal handler can be run if this process
897
982
has already completed */
898
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
983
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
984
&sigchld_action.sa_mask,
900
987
perror("sigprocmask");
901
988
exitstatus = EXIT_FAILURE;
905
FD_SET(new_plugin->fd, &rfds_all);
992
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
907
if (maxfd < new_plugin->fd){
995
if(maxfd < new_plugin->fd){
908
996
maxfd = new_plugin->fd;
1000
TEMP_FAILURE_RETRY(closedir(dir));
1002
free_plugin(getplugin(NULL));
916
1004
for(plugin *p = plugin_list; p != NULL; p = p->next){
917
1005
if(p->pid != 0){
937
1025
from one of them */
938
1026
for(plugin *proc = plugin_list; proc != NULL;){
939
1027
/* Is this process completely done? */
940
if(proc->eof and proc->completed){
1028
if(proc->completed and proc->eof){
941
1029
/* Only accept the plugin output if it exited cleanly */
942
1030
if(not WIFEXITED(proc->status)
943
1031
or WEXITSTATUS(proc->status) != 0){
944
1032
/* Bad exit by plugin */
947
1035
if(WIFEXITED(proc->status)){
948
fprintf(stderr, "Plugin %u exited with status %d\n",
949
(unsigned int) (proc->pid),
1036
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1037
" status %d\n", proc->name,
1038
(intmax_t) (proc->pid),
950
1039
WEXITSTATUS(proc->status));
951
} else if(WIFSIGNALED(proc->status)) {
952
fprintf(stderr, "Plugin %u killed by signal %d\n",
953
(unsigned int) (proc->pid),
954
WTERMSIG(proc->status));
1040
} else if(WIFSIGNALED(proc->status)){
1041
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1042
" signal %d: %s\n", proc->name,
1043
(intmax_t) (proc->pid),
1044
WTERMSIG(proc->status),
1045
strsignal(WTERMSIG(proc->status)));
955
1046
} else if(WCOREDUMP(proc->status)){
956
fprintf(stderr, "Plugin %d dumped core\n",
957
(unsigned int) (proc->pid));
1047
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1048
" core\n", proc->name, (intmax_t) (proc->pid));
961
1052
/* Remove the plugin */
962
FD_CLR(proc->fd, &rfds_all);
1053
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
964
1056
/* Block signal while modifying process_list */
965
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1057
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1059
&sigchld_action.sa_mask,
967
1062
perror("sigprocmask");
968
1063
exitstatus = EXIT_FAILURE;
1067
plugin *next_plugin = proc->next;
972
1071
/* We are done modifying process list, so unblock signal */
973
ret = sigprocmask (SIG_UNBLOCK, &sigchld_action.sa_mask,
1072
ret = (int)(TEMP_FAILURE_RETRY
1073
(sigprocmask(SIG_UNBLOCK,
1074
&sigchld_action.sa_mask, NULL)));
976
1076
perror("sigprocmask");
977
1077
exitstatus = EXIT_FAILURE;
1017
1116
proc->buffer_size += BUFFER_SIZE;
1019
1118
/* Read from the process */
1020
ret = read(proc->fd, proc->buffer + proc->buffer_length,
1119
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1121
+ proc->buffer_length,
1023
1124
/* Read error from this process; ignore the error */
1024
1125
proc = proc->next;
1029
1130
proc->eof = true;
1031
proc->buffer_length += (size_t) ret;
1132
proc->buffer_length += (size_t) sret;
1039
1140
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){