To get this branch, use:
bzr branch
http://bzr.recompile.se/loggerhead/mandos/trunk
« back to all changes in this revision
Viewing changes to plugin-runner.c
- browse files at revision 392
- compare with another revision
- download diff
- download tarball
- view history from revision 392
- Committer: Teddy Hogeborn
- Date: 2009-10-22 00:05:01 UTC
- Revision ID: teddy@fukt.bsnet.se-20091022000501-g792e99q5g1wkyet
Merge from release branch.
- files modified:
- INSTALL
added
removed
plugin-runner.c
1
/* -*- coding: utf-8 -*- */
1
/* -*- coding: utf-8; mode: c; mode: orgtbl -*- */
2
2
/*
3
3
* Mandos plugin runner - Run Mandos plugins
4
4
*
23
23
*/
24
24
25
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf() */
26
asprintf(), O_CLOEXEC */
27
27
#include <stddef.h> /* size_t, NULL */
28
28
#include <stdlib.h> /* malloc(), exit(), EXIT_FAILURE,
29
29
EXIT_SUCCESS, realloc() */
30
30
#include <stdbool.h> /* bool, true, false */
31
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
34
34
stat, waitpid(), WIFEXITED(),
35
35
WEXITSTATUS(), wait(), pid_t,
36
36
uid_t, gid_t, getuid(), getgid(),
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() */
41
WEXITSTATUS(), WTERMSIG(),
42
WCOREDUMP() */
42
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
44
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
45
46
readdir(), closedir(), dirfd() */
46
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
47
48
fcntl(), setuid(), setgid(),
52
53
close() */
53
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
54
55
FD_CLOEXEC */
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal() */
56
58
#include <errno.h> /* errno */
57
59
#include <argp.h> /* struct argp_option, struct
58
60
argp_state, struct argp,
65
67
SIG_UNBLOCK, kill(), sig_atomic_t
66
68
*/
67
69
#include <errno.h> /* errno, EBADF */
68
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
69
71
70
72
#define BUFFER_SIZE 256
71
73
82
84
char **environ;
83
85
int envc;
84
86
bool disabled;
85
87
86
88
/* Variables used for running processes*/
87
89
pid_t pid;
88
90
int fd;
108
110
}
109
111
}
110
112
/* Create a new plugin */
111
plugin *new_plugin = malloc(sizeof(plugin));
113
plugin *new_plugin = NULL;
114
do {
115
new_plugin = malloc(sizeof(plugin));
116
} while(new_plugin == NULL and errno == EINTR);
112
117
if(new_plugin == NULL){
113
118
return NULL;
114
119
}
115
120
char *copy_name = NULL;
116
121
if(name != NULL){
117
copy_name = strdup(name);
122
do {
123
copy_name = strdup(name);
124
} while(copy_name == NULL and errno == EINTR);
118
125
if(copy_name == NULL){
119
126
free(new_plugin);
120
127
return NULL;
126
133
.disabled = false,
127
134
.next = plugin_list };
128
135
129
new_plugin->argv = malloc(sizeof(char *) * 2);
136
do {
137
new_plugin->argv = malloc(sizeof(char *) * 2);
138
} while(new_plugin->argv == NULL and errno == EINTR);
130
139
if(new_plugin->argv == NULL){
131
140
free(copy_name);
132
141
free(new_plugin);
135
144
new_plugin->argv[0] = copy_name;
136
145
new_plugin->argv[1] = NULL;
137
146
138
new_plugin->environ = malloc(sizeof(char *));
147
do {
148
new_plugin->environ = malloc(sizeof(char *));
149
} while(new_plugin->environ == NULL and errno == EINTR);
139
150
if(new_plugin->environ == NULL){
140
151
free(copy_name);
141
152
free(new_plugin->argv);
153
164
static bool add_to_char_array(const char *new, char ***array,
154
165
int *len){
155
166
/* Resize the pointed-to array to hold one more pointer */
156
*array = realloc(*array, sizeof(char *)
157
* (size_t) ((*len) + 2));
167
do {
168
*array = realloc(*array, sizeof(char *)
169
* (size_t) ((*len) + 2));
170
} while(*array == NULL and errno == EINTR);
158
171
/* Malloc check */
159
172
if(*array == NULL){
160
173
return false;
161
174
}
162
175
/* Make a copy of the new string */
163
char *copy = strdup(new);
176
char *copy;
177
do {
178
copy = strdup(new);
179
} while(copy == NULL and errno == EINTR);
164
180
if(copy == NULL){
165
181
return false;
166
182
}
192
208
if(strncmp(*e, def, namelen + 1) == 0){
193
209
/* It already exists */
194
210
if(replace){
195
char *new = realloc(*e, strlen(def) + 1);
211
char *new;
212
do {
213
new = realloc(*e, strlen(def) + 1);
214
} while(new == NULL and errno == EINTR);
196
215
if(new == NULL){
197
216
return false;
198
217
}
208
227
/*
209
228
* Based on the example in the GNU LibC manual chapter 13.13 "File
210
229
* Descriptor Flags".
211
* *Note File Descriptor Flags:(libc)Descriptor Flags.
230
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
212
231
*/
213
232
static int set_cloexec_flag(int fd){
214
int ret = fcntl(fd, F_GETFD, 0);
233
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
215
234
/* If reading the flags failed, return error indication now. */
216
235
if(ret < 0){
217
236
return ret;
218
237
}
219
238
/* Store modified flag word in the descriptor. */
220
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
239
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
240
ret | FD_CLOEXEC));
221
241
}
222
242
223
243
280
300
}
281
301
free(plugin_node->environ);
282
302
free(plugin_node->buffer);
283
303
284
304
/* Removes the plugin from the singly-linked list */
285
305
if(plugin_node == plugin_list){
286
306
/* First one - simple */
313
333
struct dirent *dirst;
314
334
struct stat st;
315
335
fd_set rfds_all;
316
int ret, numchars, maxfd = 0;
336
int ret, maxfd = 0;
317
337
ssize_t sret;
318
intmax_t tmpmax;
319
338
uid_t uid = 65534;
320
339
gid_t gid = 65534;
321
340
bool debug = false;
381
400
error_t parse_opt(int key, char *arg, __attribute__((unused))
382
401
struct argp_state *state){
383
402
switch(key){
403
char *tmp;
404
intmax_t tmpmax;
384
405
case 'g': /* --global-options */
385
406
if(arg != NULL){
386
407
char *plugin_option;
456
477
plugindir = strdup(arg);
457
478
if(plugindir == NULL){
458
479
perror("strdup");
459
}
480
}
460
481
break;
461
482
case 129: /* --config-file */
462
483
/* This is already done by parse_opt_config_file() */
463
484
break;
464
485
case 130: /* --userid */
465
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
466
if(ret < 1 or tmpmax != (uid_t)tmpmax
467
or arg[numchars] != '\0'){
486
errno = 0;
487
tmpmax = strtoimax(arg, &tmp, 10);
488
if(errno != 0 or tmp == arg or *tmp != '\0'
489
or tmpmax != (uid_t)tmpmax){
468
490
fprintf(stderr, "Bad user ID number: \"%s\", using %"
469
491
PRIdMAX "\n", arg, (intmax_t)uid);
470
492
} else {
472
494
}
473
495
break;
474
496
case 131: /* --groupid */
475
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
476
if(ret < 1 or tmpmax != (gid_t)tmpmax
477
or arg[numchars] != '\0'){
497
errno = 0;
498
tmpmax = strtoimax(arg, &tmp, 10);
499
if(errno != 0 or tmp == arg or *tmp != '\0'
500
or tmpmax != (gid_t)tmpmax){
478
501
fprintf(stderr, "Bad group ID number: \"%s\", using %"
479
502
PRIdMAX "\n", arg, (intmax_t)gid);
480
503
} else {
524
547
if(argfile == NULL){
525
548
perror("strdup");
526
549
}
527
break;
550
break;
528
551
case 130: /* --userid */
529
552
case 131: /* --groupid */
530
553
case 132: /* --debug */
559
582
conffp = fopen(AFILE, "r");
560
583
} else {
561
584
conffp = fopen(argfile, "r");
562
}
585
}
563
586
if(conffp != NULL){
564
587
char *org_line = NULL;
565
588
char *p, *arg, *new_arg, *line;
566
589
size_t size = 0;
567
590
const char whitespace_delims[] = " \r\t\f\v\n";
568
591
const char comment_delim[] = "#";
569
592
570
593
custom_argc = 1;
571
594
custom_argv = malloc(sizeof(char*) * 2);
572
595
if(custom_argv == NULL){
576
599
}
577
600
custom_argv[0] = argv[0];
578
601
custom_argv[1] = NULL;
579
602
580
603
/* for each line in the config file, strip whitespace and ignore
581
604
commented text */
582
605
while(true){
584
607
if(sret == -1){
585
608
break;
586
609
}
587
610
588
611
line = org_line;
589
612
arg = strsep(&line, comment_delim);
590
613
while((p = strsep(&arg, whitespace_delims)) != NULL){
609
632
goto fallback;
610
633
}
611
634
custom_argv[custom_argc-1] = new_arg;
612
custom_argv[custom_argc] = NULL;
635
custom_argv[custom_argc] = NULL;
613
636
}
614
637
}
638
do {
639
ret = fclose(conffp);
640
} while(ret == EOF and errno == EINTR);
641
if(ret == EOF){
642
perror("fclose");
643
exitstatus = EXIT_FAILURE;
644
goto fallback;
645
}
615
646
free(org_line);
616
647
} else {
617
648
/* Check for harmful errors and go to fallback. Other errors might
667
698
perror("setuid");
668
699
}
669
700
670
if(plugindir == NULL){
671
dir = opendir(PDIR);
672
} else {
673
dir = opendir(plugindir);
674
}
675
676
if(dir == NULL){
677
perror("Could not open plugin dir");
678
exitstatus = EXIT_FAILURE;
679
goto fallback;
680
}
681
682
/* Set the FD_CLOEXEC flag on the directory, if possible */
701
/* Open plugin directory with close_on_exec flag */
683
702
{
684
int dir_fd = dirfd(dir);
685
if(dir_fd >= 0){
686
ret = set_cloexec_flag(dir_fd);
687
if(ret < 0){
688
perror("set_cloexec_flag");
689
exitstatus = EXIT_FAILURE;
690
goto fallback;
691
}
703
int dir_fd = -1;
704
if(plugindir == NULL){
705
dir_fd = open(PDIR, O_RDONLY |
706
#ifdef O_CLOEXEC
707
O_CLOEXEC
708
#else /* not O_CLOEXEC */
709
0
710
#endif /* not O_CLOEXEC */
711
);
712
} else {
713
dir_fd = open(plugindir, O_RDONLY |
714
#ifdef O_CLOEXEC
715
O_CLOEXEC
716
#else /* not O_CLOEXEC */
717
0
718
#endif /* not O_CLOEXEC */
719
);
720
}
721
if(dir_fd == -1){
722
perror("Could not open plugin dir");
723
exitstatus = EXIT_FAILURE;
724
goto fallback;
725
}
726
727
#ifndef O_CLOEXEC
728
/* Set the FD_CLOEXEC flag on the directory */
729
ret = set_cloexec_flag(dir_fd);
730
if(ret < 0){
731
perror("set_cloexec_flag");
732
TEMP_FAILURE_RETRY(close(dir_fd));
733
exitstatus = EXIT_FAILURE;
734
goto fallback;
735
}
736
#endif /* O_CLOEXEC */
737
738
dir = fdopendir(dir_fd);
739
if(dir == NULL){
740
perror("Could not open plugin dir");
741
TEMP_FAILURE_RETRY(close(dir_fd));
742
exitstatus = EXIT_FAILURE;
743
goto fallback;
692
744
}
693
745
}
694
746
696
748
697
749
/* Read and execute any executable in the plugin directory*/
698
750
while(true){
699
dirst = readdir(dir);
751
do {
752
dirst = readdir(dir);
753
} while(dirst == NULL and errno == EINTR);
700
754
701
755
/* All directory entries have been processed */
702
756
if(dirst == NULL){
753
807
continue;
754
808
}
755
809
}
756
810
757
811
char *filename;
758
812
if(plugindir == NULL){
759
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
813
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
814
dirst->d_name));
760
815
} else {
761
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
816
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
817
plugindir,
818
dirst->d_name));
762
819
}
763
820
if(ret < 0){
764
821
perror("asprintf");
765
822
continue;
766
823
}
767
824
768
ret = stat(filename, &st);
825
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
769
826
if(ret == -1){
770
827
perror("stat");
771
828
free(filename);
772
829
continue;
773
830
}
774
831
775
832
/* Ignore non-executable files */
776
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)){
777
835
if(debug){
778
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
779
837
" with bad type or mode\n", filename);
825
883
}
826
884
827
885
int pipefd[2];
828
ret = pipe(pipefd);
886
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
829
887
if(ret == -1){
830
888
perror("pipe");
831
889
exitstatus = EXIT_FAILURE;
845
903
goto fallback;
846
904
}
847
905
/* Block SIGCHLD until process is safely in process list */
848
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
906
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
907
&sigchld_action.sa_mask,
908
NULL));
849
909
if(ret < 0){
850
910
perror("sigprocmask");
851
911
exitstatus = EXIT_FAILURE;
852
912
goto fallback;
853
913
}
854
914
/* Starting a new process to be watched */
855
pid_t pid = fork();
915
pid_t pid;
916
do {
917
pid = fork();
918
} while(pid == -1 and errno == EINTR);
856
919
if(pid == -1){
857
920
perror("fork");
858
921
exitstatus = EXIT_FAILURE;
896
959
/* no return */
897
960
}
898
961
/* Parent process */
899
close(pipefd[1]); /* Close unused write end of pipe */
962
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
963
pipe */
900
964
free(filename);
901
965
plugin *new_plugin = getplugin(dirst->d_name);
902
966
if(new_plugin == NULL){
903
967
perror("getplugin");
904
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
968
ret = (int)(TEMP_FAILURE_RETRY
969
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
970
NULL)));
905
971
if(ret < 0){
906
972
perror("sigprocmask");
907
973
}
914
980
915
981
/* Unblock SIGCHLD so signal handler can be run if this process
916
982
has already completed */
917
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
983
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
984
&sigchld_action.sa_mask,
985
NULL));
918
986
if(ret < 0){
919
987
perror("sigprocmask");
920
988
exitstatus = EXIT_FAILURE;
921
989
goto fallback;
922
990
}
923
991
924
FD_SET(new_plugin->fd, &rfds_all);
992
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
993
-Wconversion */
925
994
926
995
if(maxfd < new_plugin->fd){
927
996
maxfd = new_plugin->fd;
928
997
}
929
998
}
930
999
931
closedir(dir);
1000
TEMP_FAILURE_RETRY(closedir(dir));
932
1001
dir = NULL;
933
1002
free_plugin(getplugin(NULL));
934
1003
947
1016
while(plugin_list){
948
1017
fd_set rfds = rfds_all;
949
1018
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
950
if(select_ret == -1){
1019
if(select_ret == -1 and errno != EINTR){
951
1020
perror("select");
952
1021
exitstatus = EXIT_FAILURE;
953
1022
goto fallback;
961
1030
if(not WIFEXITED(proc->status)
962
1031
or WEXITSTATUS(proc->status) != 0){
963
1032
/* Bad exit by plugin */
964
1033
965
1034
if(debug){
966
1035
if(WIFEXITED(proc->status)){
967
1036
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
970
1039
WEXITSTATUS(proc->status));
971
1040
} else if(WIFSIGNALED(proc->status)){
972
1041
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
973
" signal %d\n", proc->name,
1042
" signal %d: %s\n", proc->name,
974
1043
(intmax_t) (proc->pid),
975
WTERMSIG(proc->status));
1044
WTERMSIG(proc->status),
1045
strsignal(WTERMSIG(proc->status)));
976
1046
} else if(WCOREDUMP(proc->status)){
977
1047
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
978
1048
" core\n", proc->name, (intmax_t) (proc->pid));
980
1050
}
981
1051
982
1052
/* Remove the plugin */
983
FD_CLR(proc->fd, &rfds_all);
984
1053
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1054
-Wconversion */
1055
985
1056
/* Block signal while modifying process_list */
986
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1057
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1058
(SIG_BLOCK,
1059
&sigchld_action.sa_mask,
1060
NULL));
987
1061
if(ret < 0){
988
1062
perror("sigprocmask");
989
1063
exitstatus = EXIT_FAILURE;
995
1069
proc = next_plugin;
996
1070
997
1071
/* We are done modifying process list, so unblock signal */
998
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
999
NULL);
1072
ret = (int)(TEMP_FAILURE_RETRY
1073
(sigprocmask(SIG_UNBLOCK,
1074
&sigchld_action.sa_mask, NULL)));
1000
1075
if(ret < 0){
1001
1076
perror("sigprocmask");
1002
1077
exitstatus = EXIT_FAILURE;
1022
1097
}
1023
1098
1024
1099
/* This process has not completed. Does it have any output? */
1025
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1100
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1101
warning from
1102
-Wconversion */
1026
1103
/* This process had nothing to say at this time */
1027
1104
proc = proc->next;
1028
1105
continue;
1039
1116
proc->buffer_size += BUFFER_SIZE;
1040
1117
}
1041
1118
/* Read from the process */
1042
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1043
BUFFER_SIZE);
1119
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1120
proc->buffer
1121
+ proc->buffer_length,
1122
BUFFER_SIZE));
1044
1123
if(sret < 0){
1045
1124
/* Read error from this process; ignore the error */
1046
1125
proc = proc->next;
1054
1133
}
1055
1134
}
1056
1135
}
1057
1058
1136
1137
1059
1138
fallback:
1060
1139
1061
1140
if(plugin_list == NULL or exitstatus != EXIT_SUCCESS){
1108
1187
}
1109
1188
1110
1189
/* Wait for any remaining child processes to terminate */
1111
do{
1190
do {
1112
1191
ret = wait(NULL);
1113
1192
} while(ret >= 0);
1114
1193
if(errno != ECHILD){
Loggerhead is a web-based interface for Breezy
Version: 2.0.2.dev0