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 © 2008-2013 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
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,
861
811
ret = set_cloexec_flag(dir_fd);
863
813
error(0, errno, "set_cloexec_flag");
814
TEMP_FAILURE_RETRY(close(dir_fd));
864
815
exitstatus = EX_OSERR;
867
818
#endif /* O_CLOEXEC */
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 };
875
#pragma GCC diagnostic push
876
#pragma GCC diagnostic ignored "-Wcast-qual"
878
for(const char **pat = (const char **)patterns;
879
*pat != NULL; pat++){
881
#pragma GCC diagnostic pop
883
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
886
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
887
" matching pattern %s\n", dirent->d_name, *pat);
820
dir = fdopendir(dir_fd);
822
error(0, errno, "Could not open plugin dir");
823
TEMP_FAILURE_RETRY(close(dir_fd));
824
exitstatus = EX_OSERR;
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;
904
829
FD_ZERO(&rfds_all);
906
831
/* 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);
911
error(0, errno, "Could not open plugin");
834
dirst = readdir(dir);
835
} while(dirst == NULL and errno == EINTR);
837
/* All directory entries have been processed */
840
error(0, errno, "readdir");
841
exitstatus = EX_IOERR;
847
d_name_len = strlen(dirst->d_name);
849
/* Ignore dotfiles, backup files and other junk */
851
bool bad_name = false;
853
const char * const bad_prefixes[] = { ".", "#", NULL };
855
const char * const bad_suffixes[] = { "~", "#", ".dpkg-new",
858
".dpkg-divert", NULL };
859
#pragma GCC diagnostic push
860
#pragma GCC diagnostic ignored "-Wcast-qual"
861
for(const char **pre = (const char **)bad_prefixes;
862
*pre != NULL; pre++){
863
#pragma GCC diagnostic pop
864
size_t pre_len = strlen(*pre);
865
if((d_name_len >= pre_len)
866
and strncmp((dirst->d_name), *pre, pre_len) == 0){
868
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
869
" with bad prefix %s\n", dirst->d_name, *pre);
878
#pragma GCC diagnostic push
879
#pragma GCC diagnostic ignored "-Wcast-qual"
880
for(const char **suf = (const char **)bad_suffixes;
881
*suf != NULL; suf++){
882
#pragma GCC diagnostic pop
883
size_t suf_len = strlen(*suf);
884
if((d_name_len >= suf_len)
885
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
888
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
889
" with bad suffix %s\n", dirst->d_name, *suf);
902
if(plugindir == NULL){
903
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
906
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
911
error(0, errno, "asprintf");
915
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
915
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
917
917
error(0, errno, "stat");
923
922
/* Ignore non-executable files */
924
923
if(not S_ISREG(st.st_mode)
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
924
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
928
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
929
" with bad type or mode\n",
930
plugindir != NULL ? plugindir : PDIR,
931
direntries[i]->d_name);
926
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
927
" with bad type or mode\n", filename);
938
plugin *p = getplugin(direntries[i]->d_name);
933
plugin *p = getplugin(dirst->d_name);
940
935
error(0, errno, "getplugin");
947
941
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
948
direntries[i]->d_name);
1064
1030
_exit(EX_OSERR);
1067
if(fexecve(plugin_fd, p->argv,
1068
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1069
error(0, errno, "fexecve for %s/%s",
1070
plugindir != NULL ? plugindir : PDIR,
1071
direntries[i]->d_name);
1034
/* If dir has no file descriptor, we could not set FD_CLOEXEC
1035
above and must now close it manually here. */
1038
if(p->environ[0] == NULL){
1039
if(execv(filename, p->argv) < 0){
1040
error(0, errno, "execv for %s", filename);
1044
if(execve(filename, p->argv, p->environ) < 0){
1045
error(0, errno, "execve for %s", filename);
1074
1049
/* no return */
1076
1051
/* Parent process */
1077
close(pipefd[1]); /* Close unused write end of pipe */
1079
plugin *new_plugin = getplugin(direntries[i]->d_name);
1052
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1055
plugin *new_plugin = getplugin(dirst->d_name);
1080
1056
if(new_plugin == NULL){
1081
1057
error(0, errno, "getplugin");
1082
1058
ret = (int)(TEMP_FAILURE_RETRY
1217
1213
/* This process has not completed. Does it have any output? */
1218
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1214
#if defined (__GNUC__) and defined (__GLIBC__)
1215
#if not __GLIBC_PREREQ(2, 16)
1216
#pragma GCC diagnostic push
1217
#pragma GCC diagnostic ignored "-Wsign-conversion"
1220
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1226
#if defined (__GNUC__) and defined (__GLIBC__)
1227
#if not __GLIBC_PREREQ(2, 16)
1228
#pragma GCC diagnostic pop
1219
1231
/* This process had nothing to say at this time */
1220
1232
proc = proc->next;
1223
1235
/* Before reading, make the process' data buffer large enough */
1224
1236
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1225
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1226
+ (size_t) BUFFER_SIZE);
1227
if(new_buffer == NULL){
1237
proc->buffer = realloc(proc->buffer, proc->buffer_size
1238
+ (size_t) BUFFER_SIZE);
1239
if(proc->buffer == NULL){
1228
1240
error(0, errno, "malloc");
1229
1241
exitstatus = EX_OSERR;
1232
proc->buffer = new_buffer;
1233
1244
proc->buffer_size += BUFFER_SIZE;
1235
1246
/* Read from the process */