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- Committer: Teddy Hogeborn
- Date: 2009-01-17 02:34:57 UTC
- mfrom: (237.2.11 mandos-release)
- Revision ID: teddy@fukt.bsnet.se-20090117023457-1ll0f30sr9dzwto7
Merge from release branch.
- files modified:
- INSTALL
added
removed
plugin-runner.c
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
1
/* -*- coding: utf-8 -*- */
2
2
/*
3
3
* Mandos plugin runner - Run Mandos plugins
4
4
*
38
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
39
39
FD_SET(), FD_ISSET(), FD_CLR */
40
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
41
WEXITSTATUS(), WTERMSIG(),
42
WCOREDUMP() */
41
WEXITSTATUS() */
43
42
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
44
43
#include <iso646.h> /* and, or, not */
45
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
53
52
close() */
54
53
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
54
FD_CLOEXEC */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
55
#include <string.h> /* strsep, strlen(), asprintf() */
58
56
#include <errno.h> /* errno */
59
57
#include <argp.h> /* struct argp_option, struct
60
58
argp_state, struct argp,
64
62
#include <signal.h> /* struct sigaction, sigemptyset(),
65
63
sigaddset(), sigaction(),
66
64
sigprocmask(), SIG_BLOCK, SIGCHLD,
67
SIG_UNBLOCK, kill(), sig_atomic_t
68
*/
65
SIG_UNBLOCK, kill() */
69
66
#include <errno.h> /* errno, EBADF */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
71
68
72
69
#define BUFFER_SIZE 256
73
70
84
81
char **environ;
85
82
int envc;
86
83
bool disabled;
87
84
88
85
/* Variables used for running processes*/
89
86
pid_t pid;
90
87
int fd;
92
89
size_t buffer_size;
93
90
size_t buffer_length;
94
91
bool eof;
95
volatile sig_atomic_t completed;
96
int status;
92
volatile bool completed;
93
volatile int status;
97
94
struct plugin *next;
98
95
} plugin;
99
96
110
107
}
111
108
}
112
109
/* Create a new plugin */
113
plugin *new_plugin = NULL;
114
do {
115
new_plugin = malloc(sizeof(plugin));
116
} while(new_plugin == NULL and errno == EINTR);
110
plugin *new_plugin = malloc(sizeof(plugin));
117
111
if(new_plugin == NULL){
118
112
return NULL;
119
113
}
120
114
char *copy_name = NULL;
121
115
if(name != NULL){
122
do {
123
copy_name = strdup(name);
124
} while(copy_name == NULL and errno == EINTR);
116
copy_name = strdup(name);
125
117
if(copy_name == NULL){
126
118
free(new_plugin);
127
119
return NULL;
128
120
}
129
121
}
130
122
131
*new_plugin = (plugin){ .name = copy_name,
132
.argc = 1,
133
.disabled = false,
134
.next = plugin_list };
123
*new_plugin = (plugin) { .name = copy_name,
124
.argc = 1,
125
.disabled = false,
126
.next = plugin_list };
135
127
136
do {
137
new_plugin->argv = malloc(sizeof(char *) * 2);
138
} while(new_plugin->argv == NULL and errno == EINTR);
128
new_plugin->argv = malloc(sizeof(char *) * 2);
139
129
if(new_plugin->argv == NULL){
140
130
free(copy_name);
141
131
free(new_plugin);
144
134
new_plugin->argv[0] = copy_name;
145
135
new_plugin->argv[1] = NULL;
146
136
147
do {
148
new_plugin->environ = malloc(sizeof(char *));
149
} while(new_plugin->environ == NULL and errno == EINTR);
137
new_plugin->environ = malloc(sizeof(char *));
150
138
if(new_plugin->environ == NULL){
151
139
free(copy_name);
152
140
free(new_plugin->argv);
164
152
static bool add_to_char_array(const char *new, char ***array,
165
153
int *len){
166
154
/* Resize the pointed-to array to hold one more pointer */
167
do {
168
*array = realloc(*array, sizeof(char *)
169
* (size_t) ((*len) + 2));
170
} while(*array == NULL and errno == EINTR);
155
*array = realloc(*array, sizeof(char *)
156
* (size_t) ((*len) + 2));
171
157
/* Malloc check */
172
158
if(*array == NULL){
173
159
return false;
174
160
}
175
161
/* Make a copy of the new string */
176
char *copy;
177
do {
178
copy = strdup(new);
179
} while(copy == NULL and errno == EINTR);
162
char *copy = strdup(new);
180
163
if(copy == NULL){
181
164
return false;
182
165
}
208
191
if(strncmp(*e, def, namelen + 1) == 0){
209
192
/* It already exists */
210
193
if(replace){
211
char *new;
212
do {
213
new = realloc(*e, strlen(def) + 1);
214
} while(new == NULL and errno == EINTR);
194
char *new = realloc(*e, strlen(def) + 1);
215
195
if(new == NULL){
216
196
return false;
217
197
}
227
207
/*
228
208
* Based on the example in the GNU LibC manual chapter 13.13 "File
229
209
* Descriptor Flags".
230
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
210
* *Note File Descriptor Flags:(libc)Descriptor Flags.
231
211
*/
232
212
static int set_cloexec_flag(int fd){
233
int ret = TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
213
int ret = fcntl(fd, F_GETFD, 0);
234
214
/* If reading the flags failed, return error indication now. */
235
215
if(ret < 0){
236
216
return ret;
237
217
}
238
218
/* Store modified flag word in the descriptor. */
239
return TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD, ret | FD_CLOEXEC));
219
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
240
220
}
241
221
242
222
243
223
/* Mark processes as completed when they exit, and save their exit
244
224
status. */
245
225
static void handle_sigchld(__attribute__((unused)) int sig){
246
int old_errno = errno;
247
226
while(true){
248
227
plugin *proc = plugin_list;
249
228
int status;
253
232
break;
254
233
}
255
234
if(pid == -1){
256
if(errno == ECHILD){
257
/* No child processes */
258
break;
235
if(errno != ECHILD){
236
perror("waitpid");
259
237
}
260
perror("waitpid");
238
/* No child processes */
239
break;
261
240
}
262
241
263
242
/* A child exited, find it in process_list */
269
248
continue;
270
249
}
271
250
proc->status = status;
272
proc->completed = 1;
251
proc->completed = true;
273
252
}
274
errno = old_errno;
275
253
}
276
254
277
255
/* Prints out a password to stdout */
299
277
}
300
278
free(plugin_node->environ);
301
279
free(plugin_node->buffer);
302
280
303
281
/* Removes the plugin from the singly-linked list */
304
282
if(plugin_node == plugin_list){
305
283
/* First one - simple */
332
310
struct dirent *dirst;
333
311
struct stat st;
334
312
fd_set rfds_all;
335
int ret, maxfd = 0;
313
int ret, numchars, maxfd = 0;
336
314
ssize_t sret;
315
intmax_t tmpmax;
337
316
uid_t uid = 65534;
338
317
gid_t gid = 65534;
339
318
bool debug = false;
397
376
};
398
377
399
378
error_t parse_opt(int key, char *arg, __attribute__((unused))
400
struct argp_state *state){
401
switch(key){
402
char *tmp;
403
intmax_t tmpmax;
379
struct argp_state *state) {
380
switch(key) {
404
381
case 'g': /* --global-options */
405
382
if(arg != NULL){
406
char *plugin_option;
407
while((plugin_option = strsep(&arg, ",")) != NULL){
408
if(plugin_option[0] == '\0'){
383
char *p;
384
while((p = strsep(&arg, ",")) != NULL){
385
if(p[0] == '\0'){
409
386
continue;
410
387
}
411
if(not add_argument(getplugin(NULL), plugin_option)){
388
if(not add_argument(getplugin(NULL), p)){
412
389
perror("add_argument");
413
390
return ARGP_ERR_UNKNOWN;
414
391
}
425
402
break;
426
403
case 'o': /* --options-for */
427
404
if(arg != NULL){
428
char *plugin_name = strsep(&arg, ":");
429
if(plugin_name[0] == '\0'){
430
break;
431
}
432
char *plugin_option;
433
while((plugin_option = strsep(&arg, ",")) != NULL){
434
if(not add_argument(getplugin(plugin_name), plugin_option)){
405
char *p_name = strsep(&arg, ":");
406
if(p_name[0] == '\0' or arg == NULL){
407
break;
408
}
409
char *opt = strsep(&arg, ":");
410
if(opt[0] == '\0' or opt == NULL){
411
break;
412
}
413
char *p;
414
while((p = strsep(&opt, ",")) != NULL){
415
if(p[0] == '\0'){
416
continue;
417
}
418
if(not add_argument(getplugin(p_name), p)){
435
419
perror("add_argument");
436
420
return ARGP_ERR_UNKNOWN;
437
421
}
476
460
plugindir = strdup(arg);
477
461
if(plugindir == NULL){
478
462
perror("strdup");
479
}
463
}
480
464
break;
481
465
case 129: /* --config-file */
482
466
/* This is already done by parse_opt_config_file() */
483
467
break;
484
468
case 130: /* --userid */
485
errno = 0;
486
tmpmax = strtoimax(arg, &tmp, 10);
487
if(errno != 0 or tmp == arg or *tmp != '\0'
488
or tmpmax != (uid_t)tmpmax){
469
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
470
if(ret < 1 or tmpmax != (uid_t)tmpmax
471
or arg[numchars] != '\0'){
489
472
fprintf(stderr, "Bad user ID number: \"%s\", using %"
490
473
PRIdMAX "\n", arg, (intmax_t)uid);
491
474
} else {
493
476
}
494
477
break;
495
478
case 131: /* --groupid */
496
errno = 0;
497
tmpmax = strtoimax(arg, &tmp, 10);
498
if(errno != 0 or tmp == arg or *tmp != '\0'
499
or tmpmax != (gid_t)tmpmax){
479
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
480
if(ret < 1 or tmpmax != (gid_t)tmpmax
481
or arg[numchars] != '\0'){
500
482
fprintf(stderr, "Bad group ID number: \"%s\", using %"
501
483
PRIdMAX "\n", arg, (intmax_t)gid);
502
484
} else {
530
512
ignores everything but the --config-file option. */
531
513
error_t parse_opt_config_file(int key, char *arg,
532
514
__attribute__((unused))
533
struct argp_state *state){
534
switch(key){
515
struct argp_state *state) {
516
switch(key) {
535
517
case 'g': /* --global-options */
536
518
case 'G': /* --global-env */
537
519
case 'o': /* --options-for */
546
528
if(argfile == NULL){
547
529
perror("strdup");
548
530
}
549
break;
531
break;
550
532
case 130: /* --userid */
551
533
case 131: /* --groupid */
552
534
case 132: /* --debug */
581
563
conffp = fopen(AFILE, "r");
582
564
} else {
583
565
conffp = fopen(argfile, "r");
584
}
566
}
585
567
if(conffp != NULL){
586
568
char *org_line = NULL;
587
569
char *p, *arg, *new_arg, *line;
588
570
size_t size = 0;
589
571
const char whitespace_delims[] = " \r\t\f\v\n";
590
572
const char comment_delim[] = "#";
591
573
592
574
custom_argc = 1;
593
575
custom_argv = malloc(sizeof(char*) * 2);
594
576
if(custom_argv == NULL){
598
580
}
599
581
custom_argv[0] = argv[0];
600
582
custom_argv[1] = NULL;
601
583
602
584
/* for each line in the config file, strip whitespace and ignore
603
585
commented text */
604
586
while(true){
606
588
if(sret == -1){
607
589
break;
608
590
}
609
591
610
592
line = org_line;
611
593
arg = strsep(&line, comment_delim);
612
594
while((p = strsep(&arg, whitespace_delims)) != NULL){
631
613
goto fallback;
632
614
}
633
615
custom_argv[custom_argc-1] = new_arg;
634
custom_argv[custom_argc] = NULL;
616
custom_argv[custom_argc] = NULL;
635
617
}
636
618
}
637
do {
638
ret = fclose(conffp);
639
} while(ret == EOF and errno == EINTR);
640
if(ret == EOF){
641
perror("fclose");
642
exitstatus = EXIT_FAILURE;
643
goto fallback;
644
}
645
619
free(org_line);
646
620
} else {
647
621
/* Check for harmful errors and go to fallback. Other errors might
688
662
}
689
663
690
664
/* Strip permissions down to nobody */
665
ret = setuid(uid);
666
if(ret == -1){
667
perror("setuid");
668
}
691
669
setgid(gid);
692
670
if(ret == -1){
693
671
perror("setgid");
694
672
}
695
ret = setuid(uid);
696
if(ret == -1){
697
perror("setuid");
698
}
699
673
700
674
if(plugindir == NULL){
701
675
dir = opendir(PDIR);
726
700
727
701
/* Read and execute any executable in the plugin directory*/
728
702
while(true){
729
do {
730
dirst = readdir(dir);
731
} while(dirst == NULL and errno == EINTR);
703
dirst = readdir(dir);
732
704
733
705
/* All directory entries have been processed */
734
706
if(dirst == NULL){
770
742
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
771
743
size_t suf_len = strlen(*suf);
772
744
if((d_name_len >= suf_len)
773
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
745
and (strcmp((dirst->d_name)+d_name_len-suf_len, *suf)
774
746
== 0)){
775
747
if(debug){
776
748
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
785
757
continue;
786
758
}
787
759
}
788
760
789
761
char *filename;
790
762
if(plugindir == NULL){
791
ret = TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
792
dirst->d_name));
763
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
793
764
} else {
794
ret = TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s", plugindir,
795
dirst->d_name));
765
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
796
766
}
797
767
if(ret < 0){
798
768
perror("asprintf");
799
769
continue;
800
770
}
801
771
802
ret = TEMP_FAILURE_RETRY(stat(filename, &st));
772
ret = stat(filename, &st);
803
773
if(ret == -1){
804
774
perror("stat");
805
775
free(filename);
806
776
continue;
807
777
}
808
778
809
779
/* Ignore non-executable files */
810
if(not S_ISREG(st.st_mode)
811
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
780
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
812
781
if(debug){
813
782
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
814
783
" with bad type or mode\n", filename);
860
829
}
861
830
862
831
int pipefd[2];
863
ret = TEMP_FAILURE_RETRY(pipe(pipefd));
832
ret = pipe(pipefd);
864
833
if(ret == -1){
865
834
perror("pipe");
866
835
exitstatus = EXIT_FAILURE;
880
849
goto fallback;
881
850
}
882
851
/* Block SIGCHLD until process is safely in process list */
883
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
884
&sigchld_action.sa_mask,
885
NULL));
852
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
886
853
if(ret < 0){
887
854
perror("sigprocmask");
888
855
exitstatus = EXIT_FAILURE;
889
856
goto fallback;
890
857
}
891
858
/* Starting a new process to be watched */
892
pid_t pid;
893
do {
894
pid = fork();
895
} while(pid == -1 and errno == EINTR);
859
pid_t pid = fork();
896
860
if(pid == -1){
897
861
perror("fork");
898
862
exitstatus = EXIT_FAILURE;
936
900
/* no return */
937
901
}
938
902
/* Parent process */
939
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
940
pipe */
903
close(pipefd[1]); /* Close unused write end of pipe */
941
904
free(filename);
942
905
plugin *new_plugin = getplugin(dirst->d_name);
943
906
if(new_plugin == NULL){
944
907
perror("getplugin");
945
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
946
&sigchld_action.sa_mask,
947
NULL));
908
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
948
909
if(ret < 0){
949
910
perror("sigprocmask");
950
911
}
957
918
958
919
/* Unblock SIGCHLD so signal handler can be run if this process
959
920
has already completed */
960
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
961
&sigchld_action.sa_mask,
962
NULL));
921
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
963
922
if(ret < 0){
964
923
perror("sigprocmask");
965
924
exitstatus = EXIT_FAILURE;
973
932
}
974
933
}
975
934
976
TEMP_FAILURE_RETRY(closedir(dir));
935
closedir(dir);
977
936
dir = NULL;
978
free_plugin(getplugin(NULL));
979
937
980
938
for(plugin *p = plugin_list; p != NULL; p = p->next){
981
939
if(p->pid != 0){
992
950
while(plugin_list){
993
951
fd_set rfds = rfds_all;
994
952
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
995
if(select_ret == -1 and errno != EINTR){
953
if(select_ret == -1){
996
954
perror("select");
997
955
exitstatus = EXIT_FAILURE;
998
956
goto fallback;
1001
959
from one of them */
1002
960
for(plugin *proc = plugin_list; proc != NULL;){
1003
961
/* Is this process completely done? */
1004
if(proc->completed and proc->eof){
962
if(proc->eof and proc->completed){
1005
963
/* Only accept the plugin output if it exited cleanly */
1006
964
if(not WIFEXITED(proc->status)
1007
965
or WEXITSTATUS(proc->status) != 0){
1008
966
/* Bad exit by plugin */
1009
967
1010
968
if(debug){
1011
969
if(WIFEXITED(proc->status)){
1012
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1013
" status %d\n", proc->name,
1014
(intmax_t) (proc->pid),
970
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
971
" %d\n", (intmax_t) (proc->pid),
1015
972
WEXITSTATUS(proc->status));
1016
} else if(WIFSIGNALED(proc->status)){
1017
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1018
" signal %d: %s\n", proc->name,
1019
(intmax_t) (proc->pid),
1020
WTERMSIG(proc->status),
1021
strsignal(WTERMSIG(proc->status)));
973
} else if(WIFSIGNALED(proc->status)) {
974
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
975
" %d\n", (intmax_t) (proc->pid),
976
WTERMSIG(proc->status));
1022
977
} else if(WCOREDUMP(proc->status)){
1023
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1024
" core\n", proc->name, (intmax_t) (proc->pid));
978
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
979
(intmax_t) (proc->pid));
1025
980
}
1026
981
}
1027
982
1028
983
/* Remove the plugin */
1029
984
FD_CLR(proc->fd, &rfds_all);
1030
985
1031
986
/* Block signal while modifying process_list */
1032
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1033
&sigchld_action.sa_mask,
1034
NULL));
987
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1035
988
if(ret < 0){
1036
989
perror("sigprocmask");
1037
990
exitstatus = EXIT_FAILURE;
1043
996
proc = next_plugin;
1044
997
1045
998
/* We are done modifying process list, so unblock signal */
1046
ret = TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
1047
&sigchld_action.sa_mask,
1048
NULL));
999
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1000
NULL);
1049
1001
if(ret < 0){
1050
1002
perror("sigprocmask");
1051
1003
exitstatus = EXIT_FAILURE;
1088
1040
proc->buffer_size += BUFFER_SIZE;
1089
1041
}
1090
1042
/* Read from the process */
1091
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1092
proc->buffer
1093
+ proc->buffer_length,
1094
BUFFER_SIZE));
1043
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1044
BUFFER_SIZE);
1095
1045
if(sret < 0){
1096
1046
/* Read error from this process; ignore the error */
1097
1047
proc = proc->next;
1105
1055
}
1106
1056
}
1107
1057
}
1108
1109
1058
1059
1110
1060
fallback:
1111
1061
1112
1062
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1159
1109
}
1160
1110
1161
1111
/* Wait for any remaining child processes to terminate */
1162
do {
1112
do{
1163
1113
ret = wait(NULL);
1164
1114
} while(ret >= 0);
1165
1115
if(errno != ECHILD){
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0