19
19
* along with this program. If not, see
20
20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@recompile.se>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
25
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
27
27
#include <stddef.h> /* size_t, NULL */
28
28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
30
30
#include <stdbool.h> /* bool, true, false */
31
31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO, fclose() */
33
#include <sys/types.h> /* fstat(), struct stat, waitpid(),
34
WIFEXITED(), WEXITSTATUS(), wait(),
35
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(),
37
38
#include <sys/select.h> /* fd_set, select(), FD_ZERO(),
38
39
FD_SET(), FD_ISSET(), FD_CLR */
39
40
#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
40
41
WEXITSTATUS(), WTERMSIG(),
42
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
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,
506
488
plugin *p = getplugin(arg);
508
490
p->disabled = false;
513
494
case 128: /* --plugin-dir */
515
496
plugindir = strdup(arg);
516
if(plugindir != NULL){
520
498
case 129: /* --config-file */
521
499
/* This is already done by parse_opt_config_file() */
523
501
case 130: /* --userid */
524
tmp_id = strtoimax(arg, &tmp, 10);
502
tmpmax = strtoimax(arg, &tmp, 10);
525
503
if(errno != 0 or tmp == arg or *tmp != '\0'
526
or tmp_id != (uid_t)tmp_id){
504
or tmpmax != (uid_t)tmpmax){
527
505
argp_error(state, "Bad user ID number: \"%s\", using %"
528
506
PRIdMAX, arg, (intmax_t)uid);
534
511
case 131: /* --groupid */
535
tmp_id = strtoimax(arg, &tmp, 10);
512
tmpmax = strtoimax(arg, &tmp, 10);
536
513
if(errno != 0 or tmp == arg or *tmp != '\0'
537
or tmp_id != (gid_t)tmp_id){
514
or tmpmax != (gid_t)tmpmax){
538
515
argp_error(state, "Bad group ID number: \"%s\", using %"
539
516
PRIdMAX, arg, (intmax_t)gid);
545
521
case 132: /* --debug */
779
/* Work around Debian bug #633582:
780
<http://bugs.debian.org/633582> */
781
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
782
if(plugindir_fd == -1){
784
error(0, errno, "open(\"" PDIR "\")");
787
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
789
error(0, errno, "fstat");
791
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
792
ret = fchown(plugindir_fd, uid, gid);
794
error(0, errno, "fchown");
798
TEMP_FAILURE_RETRY(close(plugindir_fd));
802
/* Lower permissions */
745
/* Strip permissions down to nobody */
805
748
error(0, errno, "setgid");
836
790
#endif /* O_CLOEXEC */
839
int good_name(const struct dirent * const dirent){
840
const char * const patterns[] = { ".*", "#*#", "*~", "*.dpkg-new",
841
"*.dpkg-old", "*.dpkg-bak",
842
"*.dpkg-divert", NULL };
844
#pragma GCC diagnostic push
845
#pragma GCC diagnostic ignored "-Wcast-qual"
847
for(const char **pat = (const char **)patterns;
848
*pat != NULL; pat++){
850
#pragma GCC diagnostic pop
852
if(fnmatch(*pat, dirent->d_name, FNM_FILE_NAME | FNM_PERIOD)
855
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
856
" matching pattern %s\n", dirent->d_name, *pat);
792
dir = fdopendir(dir_fd);
794
error(0, errno, "Could not open plugin dir");
795
TEMP_FAILURE_RETRY(close(dir_fd));
796
exitstatus = EX_OSERR;
865
#if __GLIBC_PREREQ(2, 15)
866
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
868
#else /* not __GLIBC_PREREQ(2, 15) */
869
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
870
&direntries, good_name, alphasort);
871
#endif /* not __GLIBC_PREREQ(2, 15) */
872
#else /* not __GLIBC__ */
873
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
874
&direntries, good_name, alphasort);
875
#endif /* not __GLIBC__ */
876
if(numplugins == -1){
877
error(0, errno, "Could not scan plugin dir");
878
TEMP_FAILURE_RETRY(close(dir_fd));
879
exitstatus = EX_OSERR;
883
801
FD_ZERO(&rfds_all);
885
803
/* Read and execute any executable in the plugin directory*/
886
for(int i = 0; i < numplugins; i++){
888
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
890
error(0, errno, "Could not open plugin");
806
dirst = readdir(dir);
807
} while(dirst == NULL and errno == EINTR);
809
/* All directory entries have been processed */
812
error(0, errno, "readdir");
813
exitstatus = EX_IOERR;
819
d_name_len = strlen(dirst->d_name);
821
/* Ignore dotfiles, backup files and other junk */
823
bool bad_name = false;
825
const char const *bad_prefixes[] = { ".", "#", NULL };
827
const char const *bad_suffixes[] = { "~", "#", ".dpkg-new",
830
".dpkg-divert", NULL };
831
for(const char **pre = bad_prefixes; *pre != NULL; pre++){
832
size_t pre_len = strlen(*pre);
833
if((d_name_len >= pre_len)
834
and strncmp((dirst->d_name), *pre, pre_len) == 0){
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
837
" with bad prefix %s\n", dirst->d_name, *pre);
846
for(const char **suf = bad_suffixes; *suf != NULL; suf++){
847
size_t suf_len = strlen(*suf);
848
if((d_name_len >= suf_len)
849
and (strcmp((dirst->d_name) + d_name_len-suf_len, *suf)
852
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
853
" with bad suffix %s\n", dirst->d_name, *suf);
866
if(plugindir == NULL){
867
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
870
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
875
error(0, errno, "asprintf");
893
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
879
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
895
881
error(0, errno, "stat");
896
TEMP_FAILURE_RETRY(close(plugin_fd));
900
886
/* Ignore non-executable files */
901
887
if(not S_ISREG(st.st_mode)
902
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
888
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
905
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
906
" with bad type or mode\n",
907
plugindir != NULL ? plugindir : PDIR,
908
direntries[i]->d_name);
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
910
TEMP_FAILURE_RETRY(close(plugin_fd));
914
plugin *p = getplugin(direntries[i]->d_name);
897
plugin *p = getplugin(dirst->d_name);
916
899
error(0, errno, "getplugin");
917
TEMP_FAILURE_RETRY(close(plugin_fd));
922
905
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
923
direntries[i]->d_name);
925
TEMP_FAILURE_RETRY(close(plugin_fd));
957
940
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
958
#else /* O_CLOEXEC */
959
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
960
#endif /* O_CLOEXEC */
962
942
error(0, errno, "pipe");
963
943
exitstatus = EX_OSERR;
966
if(pipefd[0] >= FD_SETSIZE){
967
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
969
TEMP_FAILURE_RETRY(close(pipefd[0]));
970
TEMP_FAILURE_RETRY(close(pipefd[1]));
971
exitstatus = EX_OSERR;
975
946
/* Ask OS to automatic close the pipe on exec */
976
947
ret = set_cloexec_flag(pipefd[0]);
978
949
error(0, errno, "set_cloexec_flag");
979
TEMP_FAILURE_RETRY(close(pipefd[0]));
980
TEMP_FAILURE_RETRY(close(pipefd[1]));
981
950
exitstatus = EX_OSERR;
984
953
ret = set_cloexec_flag(pipefd[1]);
986
955
error(0, errno, "set_cloexec_flag");
987
TEMP_FAILURE_RETRY(close(pipefd[0]));
988
TEMP_FAILURE_RETRY(close(pipefd[1]));
989
956
exitstatus = EX_OSERR;
992
#endif /* not O_CLOEXEC */
993
959
/* Block SIGCHLD until process is safely in process list */
994
960
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
995
961
&sigchld_action.sa_mask,
1032
994
_exit(EX_OSERR);
1035
if(fexecve(plugin_fd, p->argv,
1036
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1037
error(0, errno, "fexecve for %s/%s",
1038
plugindir != NULL ? plugindir : PDIR,
1039
direntries[i]->d_name);
998
/* If dir has no file descriptor, we could not set FD_CLOEXEC
999
above and must now close it manually here. */
1002
if(p->environ[0] == NULL){
1003
if(execv(filename, p->argv) < 0){
1004
error(0, errno, "execv");
1008
if(execve(filename, p->argv, p->environ) < 0){
1009
error(0, errno, "execve");
1042
1013
/* no return */
1044
1015
/* Parent process */
1045
1016
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1047
TEMP_FAILURE_RETRY(close(plugin_fd));
1048
plugin *new_plugin = getplugin(direntries[i]->d_name);
1019
plugin *new_plugin = getplugin(dirst->d_name);
1049
1020
if(new_plugin == NULL){
1050
1021
error(0, errno, "getplugin");
1051
1022
ret = (int)(TEMP_FAILURE_RETRY
1205
1153
/* This process has not completed. Does it have any output? */
1206
#if defined (__GNUC__) and defined (__GLIBC__)
1207
#if not __GLIBC_PREREQ(2, 16)
1208
#pragma GCC diagnostic push
1209
#pragma GCC diagnostic ignored "-Wsign-conversion"
1212
1154
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1218
#if defined (__GNUC__) and defined (__GLIBC__)
1219
#if not __GLIBC_PREREQ(2, 16)
1220
#pragma GCC diagnostic pop
1223
1157
/* This process had nothing to say at this time */
1224
1158
proc = proc->next;
1227
1161
/* Before reading, make the process' data buffer large enough */
1228
1162
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1229
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1230
+ (size_t) BUFFER_SIZE);
1231
if(new_buffer == NULL){
1163
proc->buffer = realloc(proc->buffer, proc->buffer_size
1164
+ (size_t) BUFFER_SIZE);
1165
if(proc->buffer == NULL){
1232
1166
error(0, errno, "malloc");
1233
1167
exitstatus = EX_OSERR;
1236
proc->buffer = new_buffer;
1237
1170
proc->buffer_size += BUFFER_SIZE;
1239
1172
/* Read from the process */