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,
512
488
plugin *p = getplugin(arg);
514
490
p->disabled = false;
519
494
case 128: /* --plugin-dir */
521
496
plugindir = strdup(arg);
522
if(plugindir != NULL){
526
498
case 129: /* --config-file */
527
499
/* This is already done by parse_opt_config_file() */
529
501
case 130: /* --userid */
530
tmp_id = strtoimax(arg, &tmp, 10);
502
tmpmax = strtoimax(arg, &tmp, 10);
531
503
if(errno != 0 or tmp == arg or *tmp != '\0'
532
or tmp_id != (uid_t)tmp_id){
504
or tmpmax != (uid_t)tmpmax){
533
505
argp_error(state, "Bad user ID number: \"%s\", using %"
534
506
PRIdMAX, arg, (intmax_t)uid);
540
511
case 131: /* --groupid */
541
tmp_id = strtoimax(arg, &tmp, 10);
512
tmpmax = strtoimax(arg, &tmp, 10);
542
513
if(errno != 0 or tmp == arg or *tmp != '\0'
543
or tmp_id != (gid_t)tmp_id){
514
or tmpmax != (gid_t)tmpmax){
544
515
argp_error(state, "Bad group ID number: \"%s\", using %"
545
516
PRIdMAX, arg, (intmax_t)gid);
551
521
case 132: /* --debug */
554
case 133: /* --plugin-helper-dir */
555
free(pluginhelperdir);
556
pluginhelperdir = strdup(arg);
557
if(pluginhelperdir != NULL){
562
525
* These reproduce what we would get without ARGP_NO_HELP
811
/* Work around Debian bug #633582:
812
<http://bugs.debian.org/633582> */
813
int plugindir_fd = open(/* plugindir or */ PDIR, O_RDONLY);
814
if(plugindir_fd == -1){
816
error(0, errno, "open(\"" PDIR "\")");
819
ret = (int)TEMP_FAILURE_RETRY(fstat(plugindir_fd, &st));
821
error(0, errno, "fstat");
823
if(S_ISDIR(st.st_mode) and st.st_uid == 0 and st.st_gid == 0){
824
ret = fchown(plugindir_fd, uid, gid);
826
error(0, errno, "fchown");
830
TEMP_FAILURE_RETRY(close(plugindir_fd));
834
/* Lower permissions */
745
/* Strip permissions down to nobody */
837
748
error(0, errno, "setgid");
861
783
ret = set_cloexec_flag(dir_fd);
863
785
error(0, errno, "set_cloexec_flag");
786
TEMP_FAILURE_RETRY(close(dir_fd));
864
787
exitstatus = EX_OSERR;
867
790
#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);
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;
896
#if __GLIBC_PREREQ(2, 15)
897
int numplugins = scandirat(dir_fd, ".", &direntries, good_name,
899
#else /* not __GLIBC_PREREQ(2, 15) */
900
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
901
&direntries, good_name, alphasort);
902
#endif /* not __GLIBC_PREREQ(2, 15) */
903
#else /* not __GLIBC__ */
904
int numplugins = scandir(plugindir != NULL ? plugindir : PDIR,
905
&direntries, good_name, alphasort);
906
#endif /* not __GLIBC__ */
907
if(numplugins == -1){
908
error(0, errno, "Could not scan plugin dir");
910
exitstatus = EX_OSERR;
914
801
FD_ZERO(&rfds_all);
916
803
/* Read and execute any executable in the plugin directory*/
917
for(int i = 0; i < numplugins; i++){
919
int plugin_fd = openat(dir_fd, direntries[i]->d_name, O_RDONLY);
921
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");
925
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
879
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
927
881
error(0, errno, "stat");
928
TEMP_FAILURE_RETRY(close(plugin_fd));
933
886
/* Ignore non-executable files */
934
887
if(not S_ISREG(st.st_mode)
935
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, direntries[i]->d_name,
888
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
938
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
939
" with bad type or mode\n",
940
plugindir != NULL ? plugindir : PDIR,
941
direntries[i]->d_name);
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
943
TEMP_FAILURE_RETRY(close(plugin_fd));
948
plugin *p = getplugin(direntries[i]->d_name);
897
plugin *p = getplugin(dirst->d_name);
950
899
error(0, errno, "getplugin");
951
TEMP_FAILURE_RETRY(close(plugin_fd));
957
905
fprintf(stderr, "Ignoring disabled plugin \"%s\"\n",
958
direntries[i]->d_name);
960
TEMP_FAILURE_RETRY(close(plugin_fd));
993
940
ret = (int)TEMP_FAILURE_RETRY(pipe(pipefd));
994
#else /* O_CLOEXEC */
995
ret = (int)TEMP_FAILURE_RETRY(pipe2(pipefd, O_CLOEXEC));
996
#endif /* O_CLOEXEC */
998
942
error(0, errno, "pipe");
999
943
exitstatus = EX_OSERR;
1000
free(direntries[i]);
1003
if(pipefd[0] >= FD_SETSIZE){
1004
fprintf(stderr, "pipe()[0] (%d) >= FD_SETSIZE (%d)", pipefd[0],
1006
TEMP_FAILURE_RETRY(close(pipefd[0]));
1007
TEMP_FAILURE_RETRY(close(pipefd[1]));
1008
exitstatus = EX_OSERR;
1009
free(direntries[i]);
1013
946
/* Ask OS to automatic close the pipe on exec */
1014
947
ret = set_cloexec_flag(pipefd[0]);
1016
949
error(0, errno, "set_cloexec_flag");
1017
TEMP_FAILURE_RETRY(close(pipefd[0]));
1018
TEMP_FAILURE_RETRY(close(pipefd[1]));
1019
950
exitstatus = EX_OSERR;
1020
free(direntries[i]);
1023
953
ret = set_cloexec_flag(pipefd[1]);
1025
955
error(0, errno, "set_cloexec_flag");
1026
TEMP_FAILURE_RETRY(close(pipefd[0]));
1027
TEMP_FAILURE_RETRY(close(pipefd[1]));
1028
956
exitstatus = EX_OSERR;
1029
free(direntries[i]);
1032
#endif /* not O_CLOEXEC */
1033
959
/* Block SIGCHLD until process is safely in process list */
1034
960
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
1035
961
&sigchld_action.sa_mask,
1074
994
_exit(EX_OSERR);
1077
if(fexecve(plugin_fd, p->argv,
1078
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1079
error(0, errno, "fexecve for %s/%s",
1080
plugindir != NULL ? plugindir : PDIR,
1081
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");
1084
1013
/* no return */
1086
1015
/* Parent process */
1087
1016
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1089
TEMP_FAILURE_RETRY(close(plugin_fd));
1090
plugin *new_plugin = getplugin(direntries[i]->d_name);
1019
plugin *new_plugin = getplugin(dirst->d_name);
1091
1020
if(new_plugin == NULL){
1092
1021
error(0, errno, "getplugin");
1093
1022
ret = (int)(TEMP_FAILURE_RETRY
1252
1153
/* This process has not completed. Does it have any output? */
1253
#if defined (__GNUC__) and defined (__GLIBC__)
1254
#if not __GLIBC_PREREQ(2, 16)
1255
#pragma GCC diagnostic push
1256
#pragma GCC diagnostic ignored "-Wsign-conversion"
1259
1154
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1265
#if defined (__GNUC__) and defined (__GLIBC__)
1266
#if not __GLIBC_PREREQ(2, 16)
1267
#pragma GCC diagnostic pop
1270
1157
/* This process had nothing to say at this time */
1271
1158
proc = proc->next;
1274
1161
/* Before reading, make the process' data buffer large enough */
1275
1162
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1276
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1277
+ (size_t) BUFFER_SIZE);
1278
if(new_buffer == NULL){
1163
proc->buffer = realloc(proc->buffer, proc->buffer_size
1164
+ (size_t) BUFFER_SIZE);
1165
if(proc->buffer == NULL){
1279
1166
error(0, errno, "malloc");
1280
1167
exitstatus = EX_OSERR;
1283
proc->buffer = new_buffer;
1284
1170
proc->buffer_size += BUFFER_SIZE;
1286
1172
/* Read from the process */