3
3
* Mandos plugin runner - Run Mandos plugins
5
* Copyright © 2008-2020 Teddy Hogeborn
6
* Copyright © 2008-2020 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 © 2008-2013 Teddy Hogeborn
6
* Copyright © 2008-2013 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(),
26
asprintf(), O_CLOEXEC */
28
27
#include <stddef.h> /* size_t, NULL */
29
#include <stdlib.h> /* malloc(), reallocarray(), realloc(),
30
EXIT_SUCCESS, exit() */
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
31
30
#include <stdbool.h> /* bool, true, false */
32
31
#include <stdio.h> /* fileno(), fprintf(),
33
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(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), 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() */
42
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
41
WEXITSTATUS(), WTERMSIG(),
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
44
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* struct dirent, scandirat() */
45
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
46
FD_CLOEXEC, write(), STDOUT_FILENO,
47
struct stat, fstat(), close(),
48
setgid(), setuid(), S_ISREG(),
49
faccessat() pipe2(), fork(),
50
_exit(), dup2(), fexecve(), read()
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
46
readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
48
fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
50
access(), pipe(), fork(), close()
51
dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
52
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
53
FD_CLOEXEC, openat(), scandirat(),
55
#include <string.h> /* strsep, strlen(), strsignal(),
56
strcmp(), strncmp() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
57
strsignal(), strcmp(), strncmp() */
57
58
#include <errno.h> /* errno */
58
59
#include <argp.h> /* struct argp_option, struct
59
60
argp_state, struct argp,
890
837
ret = set_cloexec_flag(dir_fd);
892
839
error(0, errno, "set_cloexec_flag");
840
TEMP_FAILURE_RETRY(close(dir_fd));
893
841
exitstatus = EX_OSERR;
896
844
#endif /* O_CLOEXEC */
899
int good_name(const struct dirent * const dirent){
900
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
901
"*.dpkg-old", "*.dpkg-bak",
902
"*.dpkg-divert", NULL };
904
#pragma GCC diagnostic push
905
#pragma GCC diagnostic ignored "-Wcast-qual"
907
for(const char **pat = (const char **)patterns;
908
*pat != NULL; pat++){
910
#pragma GCC diagnostic pop
912
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
915
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
916
" matching pattern %s\n", dirent->d_name, *pat);
846
dir = fdopendir(dir_fd);
848
error(0, errno, "Could not open plugin dir");
849
TEMP_FAILURE_RETRY(close(dir_fd));
850
exitstatus = EX_OSERR;
924
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
926
if(numplugins == -1){
927
error(0, errno, "Could not scan plugin dir");
929
exitstatus = EX_OSERR;
933
855
FD_ZERO(&rfds_all);
935
857
/* Read and execute any executable in the plugin directory*/
936
for(int i = 0; i < numplugins; i++){
938
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
940
error(0, errno, "Could not open plugin");
860
dirst = readdir(dir);
861
} while(dirst == NULL and errno == EINTR);
863
/* All directory entries have been processed */
866
error(0, errno, "readdir");
867
exitstatus = EX_IOERR;
873
d_name_len = strlen(dirst->d_name);
875
/* Ignore dotfiles, backup files and other junk */
877
bool bad_name = false;
879
const char * const bad_prefixes[] = { ".", "#", NULL };
881
const char * const bad_suffixes[] = { "~", "#", ".dpkg-new",
884
".dpkg-divert", NULL };
886
#pragma GCC diagnostic push
887
#pragma GCC diagnostic ignored "-Wcast-qual"
889
for(const char **pre = (const char **)bad_prefixes;
890
*pre != NULL; pre++){
892
#pragma GCC diagnostic pop
894
size_t pre_len = strlen(*pre);
895
if((d_name_len >= pre_len)
896
and strncmp((dirst->d_name), *pre, pre_len) == 0){
898
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
899
" with bad prefix %s\n", dirst->d_name, *pre);
909
#pragma GCC diagnostic push
910
#pragma GCC diagnostic ignored "-Wcast-qual"
912
for(const char **suf = (const char **)bad_suffixes;
913
*suf != NULL; suf++){
915
#pragma GCC diagnostic pop
917
size_t suf_len = strlen(*suf);
918
if((d_name_len >= suf_len)
919
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
922
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
923
" with bad suffix %s\n", dirst->d_name, *suf);
936
if(plugindir == NULL){
937
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
940
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
945
error(0, errno, "asprintf");
944
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
949
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
946
951
error(0, errno, "stat");
952
956
/* Ignore non-executable files */
953
957
if(not S_ISREG(st.st_mode)
954
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
958
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
957
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
958
" with bad type or mode\n",
959
plugindir != NULL ? plugindir : PDIR,
960
direntries[i]->d_name);
960
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
961
" with bad type or mode\n", filename);
967
plugin *p = getplugin(direntries[i]->d_name);
967
plugin *p = getplugin(dirst->d_name);
969
969
error(0, errno, "getplugin");
976
975
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
977
direntries[i]->d_name);
1093
1064
_exit(EX_OSERR);
1096
if(fexecve(plugin_fd, p->argv,
1097
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1098
error(0, errno, "fexecve for %s/%s",
1099
plugindir != NULL ? plugindir : PDIR,
1100
direntries[i]->d_name);
1068
/* If dir has no file descriptor, we could not set FD_CLOEXEC
1069
above and must now close it manually here. */
1072
if(p->environ[0] == NULL){
1073
if(execv(filename, p->argv) < 0){
1074
error(0, errno, "execv for %s", filename);
1078
if(execve(filename, p->argv, p->environ) < 0){
1079
error(0, errno, "execve for %s", filename);
1103
1083
/* no return */
1105
1085
/* Parent process */
1106
close(pipefd[1]); /* Close unused write end of pipe */
1108
plugin *new_plugin = getplugin(direntries[i]->d_name);
1086
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1089
plugin *new_plugin = getplugin(dirst->d_name);
1109
1090
if(new_plugin == NULL){
1110
1091
error(0, errno, "getplugin");
1111
1092
ret = (int)(TEMP_FAILURE_RETRY