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_FAILURE,
29
29
EXIT_SUCCESS, realloc() */
30
30
#include <stdbool.h> /* bool, true, false */
31
31
#include <stdio.h> /* perror, fileno(), fprintf(),
32
32
stderr, STDOUT_FILENO */
33
#include <sys/types.h> /* DIR, opendir(), stat(), struct
33
#include <sys/types.h> /* DIR, fdopendir(), stat(), struct
34
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stat, waitpid(), WIFEXITED(),
35
35
WEXITSTATUS(), wait(), pid_t,
36
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
43
#include <sys/stat.h> /* struct stat, stat(), S_ISREG() */
43
44
#include <iso646.h> /* and, or, not */
44
#include <dirent.h> /* DIR, struct dirent, opendir(),
45
#include <dirent.h> /* DIR, struct dirent, fdopendir(),
45
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readdir(), closedir(), dirfd() */
46
47
#include <unistd.h> /* struct stat, stat(), S_ISREG(),
47
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fcntl(), setuid(), setgid(),
53
54
#include <fcntl.h> /* fcntl(), F_GETFD, F_SETFD,
55
#include <string.h> /* strsep, strlen(), asprintf() */
56
#include <string.h> /* strsep, strlen(), asprintf(),
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58
#include <errno.h> /* errno */
57
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#include <argp.h> /* struct argp_option, struct
58
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argp_state, struct argp,
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64
#include <signal.h> /* struct sigaction, sigemptyset(),
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sigaddset(), sigaction(),
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66
sigprocmask(), SIG_BLOCK, SIGCHLD,
65
SIG_UNBLOCK, kill() */
67
SIG_UNBLOCK, kill(), sig_atomic_t
66
69
#include <errno.h> /* errno, EBADF */
67
#include <inttypes.h> /* intmax_t, SCNdMAX, PRIdMAX, */
70
#include <inttypes.h> /* intmax_t, PRIdMAX, strtoimax() */
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72
#define BUFFER_SIZE 256
109
112
/* Create a new plugin */
110
plugin *new_plugin = malloc(sizeof(plugin));
113
plugin *new_plugin = NULL;
115
new_plugin = malloc(sizeof(plugin));
116
} while(new_plugin == NULL and errno == EINTR);
111
117
if(new_plugin == NULL){
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120
char *copy_name = NULL;
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121
if(name != NULL){
116
copy_name = strdup(name);
123
copy_name = strdup(name);
124
} while(copy_name == NULL and errno == EINTR);
117
125
if(copy_name == NULL){
122
*new_plugin = (plugin) { .name = copy_name,
125
.next = plugin_list };
131
*new_plugin = (plugin){ .name = copy_name,
134
.next = plugin_list };
127
new_plugin->argv = malloc(sizeof(char *) * 2);
137
new_plugin->argv = malloc(sizeof(char *) * 2);
138
} while(new_plugin->argv == NULL and errno == EINTR);
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139
if(new_plugin->argv == NULL){
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free(new_plugin);
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new_plugin->argv[0] = copy_name;
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145
new_plugin->argv[1] = NULL;
136
new_plugin->environ = malloc(sizeof(char *));
148
new_plugin->environ = malloc(sizeof(char *));
149
} while(new_plugin->environ == NULL and errno == EINTR);
137
150
if(new_plugin->environ == NULL){
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152
free(new_plugin->argv);
151
164
static bool add_to_char_array(const char *new, char ***array,
153
166
/* Resize the pointed-to array to hold one more pointer */
154
*array = realloc(*array, sizeof(char *)
155
* (size_t) ((*len) + 2));
168
*array = realloc(*array, sizeof(char *)
169
* (size_t) ((*len) + 2));
170
} while(*array == NULL and errno == EINTR);
156
171
/* Malloc check */
157
172
if(*array == NULL){
160
175
/* Make a copy of the new string */
161
char *copy = strdup(new);
179
} while(copy == NULL and errno == EINTR);
162
180
if(copy == NULL){
190
208
if(strncmp(*e, def, namelen + 1) == 0){
191
209
/* It already exists */
193
char *new = realloc(*e, strlen(def) + 1);
213
new = realloc(*e, strlen(def) + 1);
214
} while(new == NULL and errno == EINTR);
207
228
* Based on the example in the GNU LibC manual chapter 13.13 "File
208
229
* Descriptor Flags".
209
* *Note File Descriptor Flags:(libc)Descriptor Flags.
230
| [[info:libc:Descriptor%20Flags][File Descriptor Flags]] |
211
232
static int set_cloexec_flag(int fd){
212
int ret = fcntl(fd, F_GETFD, 0);
233
int ret = (int)TEMP_FAILURE_RETRY(fcntl(fd, F_GETFD, 0));
213
234
/* If reading the flags failed, return error indication now. */
217
238
/* Store modified flag word in the descriptor. */
218
return fcntl(fd, F_SETFD, ret | FD_CLOEXEC);
239
return (int)TEMP_FAILURE_RETRY(fcntl(fd, F_SETFD,
222
244
/* Mark processes as completed when they exit, and save their exit
224
246
static void handle_sigchld(__attribute__((unused)) int sig){
247
int old_errno = errno;
226
249
plugin *proc = plugin_list;
377
400
error_t parse_opt(int key, char *arg, __attribute__((unused))
378
struct argp_state *state) {
401
struct argp_state *state){
380
405
case 'g': /* --global-options */
383
while((p = strsep(&arg, ",")) != NULL){
408
while((plugin_option = strsep(&arg, ",")) != NULL){
409
if(plugin_option[0] == '\0'){
387
if(not add_argument(getplugin(NULL), p)){
412
if(not add_argument(getplugin(NULL), plugin_option)){
388
413
perror("add_argument");
389
414
return ARGP_ERR_UNKNOWN;
402
427
case 'o': /* --options-for */
404
char *p_name = strsep(&arg, ":");
405
if(p_name[0] == '\0' or arg == NULL){
408
char *opt = strsep(&arg, ":");
409
if(opt[0] == '\0' or opt == NULL){
413
while((p = strsep(&opt, ",")) != NULL){
417
if(not add_argument(getplugin(p_name), p)){
429
char *plugin_name = strsep(&arg, ":");
430
if(plugin_name[0] == '\0'){
434
while((plugin_option = strsep(&arg, ",")) != NULL){
435
if(not add_argument(getplugin(plugin_name), plugin_option)){
418
436
perror("add_argument");
419
437
return ARGP_ERR_UNKNOWN;
459
477
plugindir = strdup(arg);
460
478
if(plugindir == NULL){
461
479
perror("strdup");
464
482
case 129: /* --config-file */
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483
/* This is already done by parse_opt_config_file() */
467
485
case 130: /* --userid */
468
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
469
if(ret < 1 or tmpmax != (uid_t)tmpmax
470
or arg[numchars] != '\0'){
487
tmpmax = strtoimax(arg, &tmp, 10);
488
if(errno != 0 or tmp == arg or *tmp != '\0'
489
or tmpmax != (uid_t)tmpmax){
471
490
fprintf(stderr, "Bad user ID number: \"%s\", using %"
472
491
PRIdMAX "\n", arg, (intmax_t)uid);
477
496
case 131: /* --groupid */
478
ret = sscanf(arg, "%" SCNdMAX "%n", &tmpmax, &numchars);
479
if(ret < 1 or tmpmax != (gid_t)tmpmax
480
or arg[numchars] != '\0'){
498
tmpmax = strtoimax(arg, &tmp, 10);
499
if(errno != 0 or tmp == arg or *tmp != '\0'
500
or tmpmax != (gid_t)tmpmax){
481
501
fprintf(stderr, "Bad group ID number: \"%s\", using %"
482
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PRIdMAX "\n", arg, (intmax_t)gid);
511
531
ignores everything but the --config-file option. */
512
532
error_t parse_opt_config_file(int key, char *arg,
513
533
__attribute__((unused))
514
struct argp_state *state) {
534
struct argp_state *state){
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536
case 'g': /* --global-options */
517
537
case 'G': /* --global-env */
518
538
case 'o': /* --options-for */
562
582
conffp = fopen(AFILE, "r");
564
584
conffp = fopen(argfile, "r");
566
586
if(conffp != NULL){
567
587
char *org_line = NULL;
568
588
char *p, *arg, *new_arg, *line;
570
590
const char whitespace_delims[] = " \r\t\f\v\n";
571
591
const char comment_delim[] = "#";
574
594
custom_argv = malloc(sizeof(char*) * 2);
575
595
if(custom_argv == NULL){
614
634
custom_argv[custom_argc-1] = new_arg;
615
custom_argv[custom_argc] = NULL;
635
custom_argv[custom_argc] = NULL;
639
ret = fclose(conffp);
640
} while(ret == EOF and errno == EINTR);
643
exitstatus = EXIT_FAILURE;
620
648
/* Check for harmful errors and go to fallback. Other errors might
663
691
/* Strip permissions down to nobody */
664
696
ret = setuid(uid);
666
698
perror("setuid");
673
if(plugindir == NULL){
676
dir = opendir(plugindir);
680
perror("Could not open plugin dir");
681
exitstatus = EXIT_FAILURE;
685
/* Set the FD_CLOEXEC flag on the directory, if possible */
701
/* Open plugin directory with close_on_exec flag */
687
int dir_fd = dirfd(dir);
689
ret = set_cloexec_flag(dir_fd);
691
perror("set_cloexec_flag");
692
exitstatus = EXIT_FAILURE;
704
if(plugindir == NULL){
705
dir_fd = open(PDIR, O_RDONLY |
708
#else /* not O_CLOEXEC */
710
#endif /* not O_CLOEXEC */
713
dir_fd = open(plugindir, O_RDONLY |
716
#else /* not O_CLOEXEC */
718
#endif /* not O_CLOEXEC */
722
perror("Could not open plugin dir");
723
exitstatus = EXIT_FAILURE;
728
/* Set the FD_CLOEXEC flag on the directory */
729
ret = set_cloexec_flag(dir_fd);
731
perror("set_cloexec_flag");
732
TEMP_FAILURE_RETRY(close(dir_fd));
733
exitstatus = EXIT_FAILURE;
736
#endif /* O_CLOEXEC */
738
dir = fdopendir(dir_fd);
740
perror("Could not open plugin dir");
741
TEMP_FAILURE_RETRY(close(dir_fd));
742
exitstatus = EXIT_FAILURE;
761
812
if(plugindir == NULL){
762
ret = asprintf(&filename, PDIR "/%s", dirst->d_name);
813
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, PDIR "/%s",
764
ret = asprintf(&filename, "%s/%s", plugindir, dirst->d_name);
816
ret = (int)TEMP_FAILURE_RETRY(asprintf(&filename, "%s/%s",
767
821
perror("asprintf");
771
ret = stat(filename, &st);
825
ret = (int)TEMP_FAILURE_RETRY(stat(filename, &st));
778
832
/* Ignore non-executable files */
779
if(not S_ISREG(st.st_mode) or (access(filename, X_OK) != 0)){
833
if(not S_ISREG(st.st_mode)
834
or (TEMP_FAILURE_RETRY(access(filename, X_OK)) != 0)){
781
836
fprintf(stderr, "Ignoring plugin dir entry \"%s\""
782
837
" with bad type or mode\n", filename);
850
905
/* Block SIGCHLD until process is safely in process list */
851
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
906
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_BLOCK,
907
&sigchld_action.sa_mask,
853
910
perror("sigprocmask");
854
911
exitstatus = EXIT_FAILURE;
857
914
/* Starting a new process to be watched */
918
} while(pid == -1 and errno == EINTR);
861
921
exitstatus = EXIT_FAILURE;
901
961
/* Parent process */
902
close(pipefd[1]); /* Close unused write end of pipe */
962
TEMP_FAILURE_RETRY(close(pipefd[1])); /* Close unused write end of
904
965
plugin *new_plugin = getplugin(dirst->d_name);
905
966
if(new_plugin == NULL){
906
967
perror("getplugin");
907
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
968
ret = (int)(TEMP_FAILURE_RETRY
969
(sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
909
972
perror("sigprocmask");
918
981
/* Unblock SIGCHLD so signal handler can be run if this process
919
982
has already completed */
920
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask, NULL);
983
ret = (int)TEMP_FAILURE_RETRY(sigprocmask(SIG_UNBLOCK,
984
&sigchld_action.sa_mask,
922
987
perror("sigprocmask");
923
988
exitstatus = EXIT_FAILURE;
927
FD_SET(new_plugin->fd, &rfds_all);
992
FD_SET(new_plugin->fd, &rfds_all); /* Spurious warning from
929
995
if(maxfd < new_plugin->fd){
930
996
maxfd = new_plugin->fd;
1000
TEMP_FAILURE_RETRY(closedir(dir));
1002
free_plugin(getplugin(NULL));
937
1004
for(plugin *p = plugin_list; p != NULL; p = p->next){
938
1005
if(p->pid != 0){
949
1016
while(plugin_list){
950
1017
fd_set rfds = rfds_all;
951
1018
int select_ret = select(maxfd+1, &rfds, NULL, NULL, NULL);
952
if(select_ret == -1){
1019
if(select_ret == -1 and errno != EINTR){
953
1020
perror("select");
954
1021
exitstatus = EXIT_FAILURE;
958
1025
from one of them */
959
1026
for(plugin *proc = plugin_list; proc != NULL;){
960
1027
/* Is this process completely done? */
961
if(proc->eof and proc->completed){
1028
if(proc->completed and proc->eof){
962
1029
/* Only accept the plugin output if it exited cleanly */
963
1030
if(not WIFEXITED(proc->status)
964
1031
or WEXITSTATUS(proc->status) != 0){
965
1032
/* Bad exit by plugin */
968
1035
if(WIFEXITED(proc->status)){
969
fprintf(stderr, "Plugin %" PRIdMAX " exited with status"
970
" %d\n", (intmax_t) (proc->pid),
1036
fprintf(stderr, "Plugin %s [%" PRIdMAX "] exited with"
1037
" status %d\n", proc->name,
1038
(intmax_t) (proc->pid),
971
1039
WEXITSTATUS(proc->status));
972
} else if(WIFSIGNALED(proc->status)) {
973
fprintf(stderr, "Plugin %" PRIdMAX " killed by signal"
974
" %d\n", (intmax_t) (proc->pid),
975
WTERMSIG(proc->status));
1040
} else if(WIFSIGNALED(proc->status)){
1041
fprintf(stderr, "Plugin %s [%" PRIdMAX "] killed by"
1042
" signal %d: %s\n", proc->name,
1043
(intmax_t) (proc->pid),
1044
WTERMSIG(proc->status),
1045
strsignal(WTERMSIG(proc->status)));
976
1046
} else if(WCOREDUMP(proc->status)){
977
fprintf(stderr, "Plugin %" PRIdMAX " dumped core\n",
978
(intmax_t) (proc->pid));
1047
fprintf(stderr, "Plugin %s [%" PRIdMAX "] dumped"
1048
" core\n", proc->name, (intmax_t) (proc->pid));
982
1052
/* Remove the plugin */
983
FD_CLR(proc->fd, &rfds_all);
1053
FD_CLR(proc->fd, &rfds_all); /* Spurious warning from
985
1056
/* Block signal while modifying process_list */
986
ret = sigprocmask(SIG_BLOCK, &sigchld_action.sa_mask, NULL);
1057
ret = (int)TEMP_FAILURE_RETRY(sigprocmask
1059
&sigchld_action.sa_mask,
988
1062
perror("sigprocmask");
989
1063
exitstatus = EXIT_FAILURE;
995
1069
proc = next_plugin;
997
1071
/* We are done modifying process list, so unblock signal */
998
ret = sigprocmask(SIG_UNBLOCK, &sigchld_action.sa_mask,
1072
ret = (int)(TEMP_FAILURE_RETRY
1073
(sigprocmask(SIG_UNBLOCK,
1074
&sigchld_action.sa_mask, NULL)));
1001
1076
perror("sigprocmask");
1002
1077
exitstatus = EXIT_FAILURE;
1024
1099
/* This process has not completed. Does it have any output? */
1025
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){
1100
if(proc->eof or not FD_ISSET(proc->fd, &rfds)){ /* Spurious
1026
1103
/* This process had nothing to say at this time */
1027
1104
proc = proc->next;
1039
1116
proc->buffer_size += BUFFER_SIZE;
1041
1118
/* Read from the process */
1042
sret = read(proc->fd, proc->buffer + proc->buffer_length,
1119
sret = TEMP_FAILURE_RETRY(read(proc->fd,
1121
+ proc->buffer_length,
1045
1124
/* Read error from this process; ignore the error */
1046
1125
proc = proc->next;