3
3
* Mandos plugin runner - Run Mandos plugins
5
* Copyright © 2008-2018 Teddy Hogeborn
6
* Copyright © 2008-2018 Björn Påhlsson
8
* This file is part of Mandos.
10
* Mandos is free software: you can redistribute it and/or modify it
11
* under the terms of the GNU General Public License as published by
12
* the Free Software Foundation, either version 3 of the License, or
13
* (at your option) any later version.
15
* Mandos is distributed in the hope that it will be useful, but
5
* Copyright © 2008-2014 Teddy Hogeborn
6
* Copyright © 2008-2014 Björn Påhlsson
8
* This program is free software: you can redistribute it and/or
9
* modify it under the terms of the GNU General Public License as
10
* published by the Free Software Foundation, either version 3 of the
11
* License, or (at your option) any later version.
13
* This program is distributed in the hope that it will be useful, but
16
14
* WITHOUT ANY WARRANTY; without even the implied warranty of
17
15
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18
16
* General Public License for more details.
20
18
* You should have received a copy of the GNU General Public License
21
* along with Mandos. If not, see <http://www.gnu.org/licenses/>.
19
* along with this program. If not, see
20
* <http://www.gnu.org/licenses/>.
23
22
* Contact the authors at <mandos@recompile.se>.
26
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
28
27
#include <stddef.h> /* size_t, NULL */
29
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
31
30
#include <stdbool.h> /* bool, true, false */
32
31
#include <stdio.h> /* fileno(), fprintf(),
33
32
stderr, STDOUT_FILENO, fclose() */
34
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
35
WIFEXITED(), WEXITSTATUS(), wait(),
36
pid_t, uid_t, gid_t, getuid(),
33
#include <sys/types.h> /* DIR, fdopendir(), fstat(), struct
34
stat, waitpid(), WIFEXITED(),
35
WEXITSTATUS(), wait(), pid_t,
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(), WTERMSIG() */
41
WEXITSTATUS(), WTERMSIG(),
42
43
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
43
44
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
46
readdir(), closedir(), dirfd() */
45
47
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
46
48
FD_CLOEXEC, write(), STDOUT_FILENO,
47
49
struct stat, fstat(), close(),
48
50
setgid(), setuid(), S_ISREG(),
49
faccessat() pipe2(), fork(),
51
faccessat() pipe(), fork(),
50
52
_exit(), dup2(), fexecve(), read()
52
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC, openat(), scandirat(),
55
FD_CLOEXEC, openat() */
55
56
#include <string.h> /* strsep, strlen(), strsignal(),
56
57
strcmp(), strncmp() */
57
58
#include <errno.h> /* errno */
779
char *pluginhelperenv;
781
ret = asprintf(&pluginhelperenv, "MANDOSPLUGINHELPERDIR=%s",
782
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
784
bret = add_environment(getplugin(NULL), pluginhelperenv, true);
786
if(ret == -1 or not bret){
787
error(0, errno, "Failed to set MANDOSPLUGINHELPERDIR"
788
" environment variable to \"%s\" for all plugins\n",
789
pluginhelperdir != NULL ? pluginhelperdir : PHDIR);
792
free(pluginhelperenv);
797
for(plugin *p = plugin_list; p != NULL; p = p->next){
765
for(plugin *p = plugin_list; p != NULL; p=p->next){
798
766
fprintf(stderr, "Plugin: %s has %d arguments\n",
799
767
p->name ? p->name : "Global", p->argc - 1);
800
768
for(char **a = p->argv; *a != NULL; a++){
861
829
ret = set_cloexec_flag(dir_fd);
863
831
error(0, errno, "set_cloexec_flag");
832
TEMP_FAILURE_RETRY(close(dir_fd));
864
833
exitstatus = EX_OSERR;
867
836
#endif /* O_CLOEXEC */
838
dir = fdopendir(dir_fd);
840
error(0, errno, "Could not open plugin dir");
841
TEMP_FAILURE_RETRY(close(dir_fd));
842
exitstatus = EX_OSERR;
870
int good_name(const struct dirent * const dirent){
871
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
872
"*.dpkg-old", "*.dpkg-bak",
873
"*.dpkg-divert", NULL };
849
/* Read and execute any executable in the plugin directory*/
852
dirst = readdir(dir);
853
} while(dirst == NULL and errno == EINTR);
855
/* All directory entries have been processed */
858
error(0, errno, "readdir");
859
exitstatus = EX_IOERR;
865
/* Ignore dotfiles, backup files and other junk */
867
bool bad_name = false;
868
const char * const patterns[] = { ".*", "#*#", "*~",
869
"*.dpkg-new", "*.dpkg-old",
870
"*.dpkg-bak", "*.dpkg-divert",
875
873
#pragma GCC diagnostic push
876
874
#pragma GCC diagnostic ignored "-Wcast-qual"
878
for(const char **pat = (const char **)patterns;
879
*pat != NULL; pat++){
876
for(const char **pat = (const char **)patterns;
877
*pat != NULL; pat++){
881
879
#pragma GCC diagnostic pop
883
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
881
if(fnmatch(*pat, dirst->d_name,
882
FNM_FILE_NAME | FNM_PERIOD) != FNM_NOMATCH){
886
884
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
887
" matching pattern %s\n", dirent->d_name, *pat);
885
" matching pattern %s\n", dirst->d_name, *pat);
895
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
897
if(numplugins == -1){
898
error(0, errno, "Could not scan plugin dir");
900
exitstatus = EX_OSERR;
906
/* Read and execute any executable in the plugin directory*/
907
for(int i = 0; i < numplugins; i++){
909
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
896
int plugin_fd = openat(dir_fd, dirst->d_name, O_RDONLY |
899
#else /* not O_CLOEXEC */
901
#endif /* not O_CLOEXEC */
910
903
if(plugin_fd == -1){
911
904
error(0, errno, "Could not open plugin");
908
/* Set the FD_CLOEXEC flag on the plugin FD */
909
ret = set_cloexec_flag(plugin_fd);
911
error(0, errno, "set_cloexec_flag");
912
TEMP_FAILURE_RETRY(close(plugin_fd));
915
#endif /* O_CLOEXEC */
915
916
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
917
918
error(0, errno, "stat");
919
TEMP_FAILURE_RETRY(close(plugin_fd));
923
923
/* Ignore non-executable files */
924
924
if(not S_ISREG(st.st_mode)
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, dirst->d_name, X_OK,
928
928
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
929
929
" with bad type or mode\n",
930
plugindir != NULL ? plugindir : PDIR,
931
direntries[i]->d_name);
930
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
932
TEMP_FAILURE_RETRY(close(plugin_fd));
938
plugin *p = getplugin(direntries[i]->d_name);
936
plugin *p = getplugin(dirst->d_name);
940
938
error(0, errno, "getplugin");
939
TEMP_FAILURE_RETRY(close(plugin_fd));
947
944
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
948
direntries[i]->d_name);
947
TEMP_FAILURE_RETRY(close(plugin_fd));
983
978
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
984
#else /* O_CLOEXEC */
985
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
986
#endif /* O_CLOEXEC */
988
980
error(0, errno, "pipe");
989
981
exitstatus = EX_OSERR;
993
984
if(pipefd[0] >= FD_SETSIZE){
994
985
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
987
TEMP_FAILURE_RETRY(close(pipefd[0]));
988
TEMP_FAILURE_RETRY(close(pipefd[1]));
998
989
exitstatus = EX_OSERR;
1003
992
/* Ask OS to automatic close the pipe on exec */
1004
993
ret = set_cloexec_flag(pipefd[0]);
1006
995
error(0, errno, "set_cloexec_flag");
996
TEMP_FAILURE_RETRY(close(pipefd[0]));
997
TEMP_FAILURE_RETRY(close(pipefd[1]));
1009
998
exitstatus = EX_OSERR;
1010
free(direntries[i]);
1013
1001
ret = set_cloexec_flag(pipefd[1]);
1015
1003
error(0, errno, "set_cloexec_flag");
1004
TEMP_FAILURE_RETRY(close(pipefd[0]));
1005
TEMP_FAILURE_RETRY(close(pipefd[1]));
1018
1006
exitstatus = EX_OSERR;
1019
free(direntries[i]);
1022
#endif /* not O_CLOEXEC */
1023
1009
/* Block SIGCHLD until process is safely in process list */
1024
1010
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1025
1011
&sigchld_action.sa_mask,
1064
1048
_exit(EX_OSERR);
1052
/* If dir has no file descriptor, we could not set FD_CLOEXEC
1053
above and must now close it manually here. */
1067
1056
if(fexecve(plugin_fd, p->argv,
1068
1057
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1069
1058
error(0, errno, "fexecve for %s/%s",
1070
plugindir != NULL ? plugindir : PDIR,
1071
direntries[i]->d_name);
1059
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
1072
1060
_exit(EX_OSERR);
1074
1062
/* no return */
1076
1064
/* Parent process */
1077
close(pipefd[1]); /* Close unused write end of pipe */
1079
plugin *new_plugin = getplugin(direntries[i]->d_name);
1065
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1067
TEMP_FAILURE_RETRY(close(plugin_fd));
1068
plugin *new_plugin = getplugin(dirst->d_name);
1080
1069
if(new_plugin == NULL){
1081
1070
error(0, errno, "getplugin");
1082
1071
ret = (int)(TEMP_FAILURE_RETRY
1165
1158
(intmax_t) (proc->pid),
1166
1159
WTERMSIG(proc->status),
1167
1160
strsignal(WTERMSIG(proc->status)));
1161
} else if(WCOREDUMP(proc->status)){
1162
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1163
" core\n", proc->name, (intmax_t) (proc->pid));
1171
1167
/* Remove the plugin */
1172
FD_CLR(proc->fd, &rfds_all);
1168
#if defined (__GNUC__) and defined (__GLIBC__)
1169
#if not __GLIBC_PREREQ(2, 16)
1170
#pragma GCC diagnostic push
1171
#pragma GCC diagnostic ignored "-Wsign-conversion"
1174
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
1175
-Wconversion in GNU libc
1177
#if defined (__GNUC__) and defined (__GLIBC__)
1178
#if not __GLIBC_PREREQ(2, 16)
1179
#pragma GCC diagnostic pop
1174
1183
/* Block signal while modifying process_list */
1175
1184
ret = (int)TEMP_FAILURE_RETRY(sigprocmask