19
19
* along with this program. If not, see
20
20
* <http://www.gnu.org/licenses/>.
22
* Contact the authors at <mandos@fukt.bsnet.se>.
22
* Contact the authors at <mandos@recompile.se>.
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25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), getline(),
26
asprintf(), O_CLOEXEC */
27
27
#include <stddef.h> /* size_t, NULL */
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28
#include <stdlib.h> /* malloc(), exit(), EXIT_SUCCESS,
30
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#include <stdbool.h> /* bool, true, false */
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31
#include <stdio.h> /* fileno(), fprintf(),
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
32
stderr, STDOUT_FILENO, fclose() */
33
#include <sys/types.h> /* DIR, fdopendir(), fstat(), struct
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stat, waitpid(), WIFEXITED(),
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WEXITSTATUS(), wait(), pid_t,
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uid_t, gid_t, getuid(), getgid(),
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#include <sys/wait.h> /* wait(), waitpid(), WIFEXITED(),
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WEXITSTATUS(), WTERMSIG(),
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
#include <sys/stat.h> /* struct stat, fstat(), S_ISREG() */
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#include <iso646.h> /* and, or, not */
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#include <dirent.h> /* DIR, struct dirent, fdopendir(),
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readdir(), closedir(), dirfd() */
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
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fcntl(), setuid(), setgid(),
49
F_GETFD, F_SETFD, FD_CLOEXEC,
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access(), pipe(), fork(), close()
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dup2(), STDOUT_FILENO, _exit(),
52
execv(), write(), read(),
47
#include <unistd.h> /* fcntl(), F_GETFD, F_SETFD,
48
FD_CLOEXEC, write(), STDOUT_FILENO,
49
struct stat, fstat(), close(),
50
setgid(), setuid(), S_ISREG(),
51
faccessat() pipe(), fork(),
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_exit(), dup2(), fexecve(), read()
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#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
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#include <string.h> /* strsep, strlen(), asprintf(),
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strsignal(), strcmp(), strncmp() */
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FD_CLOEXEC, openat() */
56
#include <string.h> /* strsep, strlen(), strsignal(),
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strcmp(), strncmp() */
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#include <errno.h> /* errno */
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#include <argp.h> /* struct argp_option, struct
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argp_state, struct argp,
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/* Helper function for add_argument and add_environment */
176
__attribute__((nonnull, warn_unused_result))
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177
static bool add_to_char_array(const char *new, char ***array,
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179
/* Resize the pointed-to array to hold one more pointer */
180
char **new_array = NULL;
178
*array = realloc(*array, sizeof(char *)
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* (size_t) ((*len) + 2));
180
} while(*array == NULL and errno == EINTR);
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new_array = realloc(*array, sizeof(char *)
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* (size_t) ((*len) + 2));
184
} while(new_array == NULL and errno == EINTR);
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/* Malloc check */
186
if(new_array == NULL){
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/* Make a copy of the new string */
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/* namelen = length of name of environment variable */
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size_t namelen = (size_t)(strchrnul(def, '=') - def);
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/* Search for this environment variable */
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for(char **e = p->environ; *e != NULL; e++){
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if(strncmp(*e, def, namelen + 1) == 0){
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for(char **envdef = p->environ; *envdef != NULL; envdef++){
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if(strncmp(*envdef, def, namelen + 1) == 0){
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/* It already exists */
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new = realloc(*e, strlen(def) + 1);
224
} while(new == NULL and errno == EINTR);
230
new_envdef = realloc(*envdef, strlen(def) + 1);
231
} while(new_envdef == NULL and errno == EINTR);
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if(new_envdef == NULL){
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*envdef = new_envdef;
236
strcpy(*envdef, def);
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506
plugin *p = getplugin(arg);
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508
p->disabled = false;
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513
case 128: /* --plugin-dir */
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515
plugindir = strdup(arg);
516
if(plugindir != NULL){
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520
case 129: /* --config-file */
499
521
/* This is already done by parse_opt_config_file() */
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523
case 130: /* --userid */
502
tmpmax = strtoimax(arg, &tmp, 10);
524
tmp_id = strtoimax(arg, &tmp, 10);
503
525
if(errno != 0 or tmp == arg or *tmp != '\0'
504
or tmpmax != (uid_t)tmpmax){
526
or tmp_id != (uid_t)tmp_id){
505
527
argp_error(state, "Bad user ID number: \"%s\", using %"
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528
PRIdMAX, arg, (intmax_t)uid);
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534
case 131: /* --groupid */
512
tmpmax = strtoimax(arg, &tmp, 10);
535
tmp_id = strtoimax(arg, &tmp, 10);
513
536
if(errno != 0 or tmp == arg or *tmp != '\0'
514
or tmpmax != (gid_t)tmpmax){
537
or tmp_id != (gid_t)tmp_id){
515
538
argp_error(state, "Bad group ID number: \"%s\", using %"
516
539
PRIdMAX, arg, (intmax_t)gid);
521
545
case 132: /* --debug */
745
/* Strip permissions down to nobody */
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 */
748
805
error(0, errno, "setgid");
755
812
/* Open plugin directory with close_on_exec flag */
758
if(plugindir == NULL){
759
dir_fd = open(PDIR, O_RDONLY |
762
#else /* not O_CLOEXEC */
764
#endif /* not O_CLOEXEC */
767
dir_fd = open(plugindir, O_RDONLY |
770
#else /* not O_CLOEXEC */
772
#endif /* not O_CLOEXEC */
814
dir_fd = open(plugindir != NULL ? plugindir : PDIR, O_RDONLY |
817
#else /* not O_CLOEXEC */
819
#endif /* not O_CLOEXEC */
775
821
if(dir_fd == -1){
776
822
error(0, errno, "Could not open plugin dir");
777
823
exitstatus = EX_UNAVAILABLE;
819
d_name_len = strlen(dirst->d_name);
821
865
/* Ignore dotfiles, backup files and other junk */
823
867
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);
868
const char * const patterns[] = { ".*", "#*#", "*~",
869
"*.dpkg-new", "*.dpkg-old",
870
"*.dpkg-bak", "*.dpkg-divert",
873
#pragma GCC diagnostic push
874
#pragma GCC diagnostic ignored "-Wcast-qual"
876
for(const char **pat = (const char **)patterns;
877
*pat != NULL; pat++){
879
#pragma GCC diagnostic pop
881
if(fnmatch(*pat, dirst->d_name,
882
FNM_FILE_NAME | FNM_PERIOD) != FNM_NOMATCH){
884
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
885
" matching pattern %s\n", dirst->d_name, *pat);
866
if(plugindir == NULL){
867
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
870
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
896
int plugin_fd = openat(dir_fd, dirst->d_name, O_RDONLY |
899
#else /* not O_CLOEXEC */
901
#endif /* not O_CLOEXEC */
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);
875
error(0, errno, "asprintf");
911
error(0, errno, "set_cloexec_flag");
912
TEMP_FAILURE_RETRY(close(plugin_fd));
879
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
915
#endif /* O_CLOEXEC */
916
ret = (int)TEMP_FAILURE_RETRY(fstat(plugin_fd, &st));
881
918
error(0, errno, "stat");
919
TEMP_FAILURE_RETRY(close(plugin_fd));
886
923
/* Ignore non-executable files */
887
924
if(not S_ISREG(st.st_mode)
888
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
925
or (TEMP_FAILURE_RETRY(faccessat(dir_fd, dirst->d_name, X_OK,
890
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
891
" with bad type or mode\n", filename);
928
fprintf(stderr, "Ignoring plugin dir entry \"%s/%s\""
929
" with bad type or mode\n",
930
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
932
TEMP_FAILURE_RETRY(close(plugin_fd));
897
936
plugin *p = getplugin(dirst->d_name);
899
938
error(0, errno, "getplugin");
939
TEMP_FAILURE_RETRY(close(plugin_fd));
999
1037
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");
1040
if(fexecve(plugin_fd, p->argv,
1041
(p->environ[0] != NULL) ? p->environ : environ) < 0){
1042
error(0, errno, "fexecve for %s/%s",
1043
plugindir != NULL ? plugindir : PDIR, dirst->d_name);
1013
1046
/* no return */
1015
1048
/* Parent process */
1016
1049
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
1051
TEMP_FAILURE_RETRY(close(plugin_fd));
1019
1052
plugin *new_plugin = getplugin(dirst->d_name);
1020
1053
if(new_plugin == NULL){
1021
1054
error(0, errno, "getplugin");
1153
1210
/* This process has not completed. Does it have any output? */
1211
#if defined (__GNUC__) and defined (__GLIBC__)
1212
#if not __GLIBC_PREREQ(2, 16)
1213
#pragma GCC diagnostic push
1214
#pragma GCC diagnostic ignored "-Wsign-conversion"
1154
1217
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1223
#if defined (__GNUC__) and defined (__GLIBC__)
1224
#if not __GLIBC_PREREQ(2, 16)
1225
#pragma GCC diagnostic pop
1157
1228
/* This process had nothing to say at this time */
1158
1229
proc = proc->next;
1161
1232
/* Before reading, make the process' data buffer large enough */
1162
1233
if(proc->buffer_length + BUFFER_SIZE > proc->buffer_size){
1163
proc->buffer = realloc(proc->buffer, proc->buffer_size
1164
+ (size_t) BUFFER_SIZE);
1165
if(proc->buffer == NULL){
1234
char *new_buffer = realloc(proc->buffer, proc->buffer_size
1235
+ (size_t) BUFFER_SIZE);
1236
if(new_buffer == NULL){
1166
1237
error(0, errno, "malloc");
1167
1238
exitstatus = EX_OSERR;
1241
proc->buffer = new_buffer;
1170
1242
proc->buffer_size += BUFFER_SIZE;
1172
1244
/* Read from the process */