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- Committer: Teddy Hogeborn
- Date: 2009-09-23 08:52:09 UTC
- Revision ID: teddy@fukt.bsnet.se-20090923085209-n6nx3i86rvokwfq6
* plugin-runner.c (main): Use the O_CLOEXEC flag, if available, when
opening the plugin directory.
opening the plugin directory.
- files added:
- debian/watch
- files removed:
- debian/mandos-client.config
- files renamed:
- mandos-list => mandos-ctl
- files modified:
- INSTALL
added
removed
plugins.d/splashy.c
1
1
/* -*- coding: utf-8 -*- */
2
2
/*
3
* Passprompt - Read a password from splashy and output it
3
* Splashy - Read a password from splashy and output it
4
4
*
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* Copyright © 2008 Teddy Hogeborn
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* Copyright © 2008 Björn Påhlsson
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* Copyright © 2008,2009 Teddy Hogeborn
6
* Copyright © 2008,2009 Björn Påhlsson
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*
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* This program is free software: you can redistribute it and/or
9
9
* modify it under the terms of the GNU General Public License as
19
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* along with this program. If not, see
20
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* <http://www.gnu.org/licenses/>.
21
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*
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* Contact the authors at <https://www.fukt.bsnet.se/~belorn/> and
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* <https://www.fukt.bsnet.se/~teddy/>.
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* Contact the authors at <mandos@fukt.bsnet.se>.
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*/
25
24
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#define _GNU_SOURCE /* asprintf() */
25
#define _GNU_SOURCE /* TEMP_FAILURE_RETRY(), asprintf() */
27
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#include <signal.h> /* sig_atomic_t, struct sigaction,
28
27
sigemptyset(), sigaddset(), SIGINT,
29
28
SIGHUP, SIGTERM, sigaction,
31
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#include <stddef.h> /* NULL */
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31
#include <stdlib.h> /* getenv() */
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#include <stdio.h> /* asprintf(), perror() */
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#include <stdlib.h> /* EXIT_FAILURE, free(), strtoul(),
33
#include <stdlib.h> /* EXIT_FAILURE, free(),
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EXIT_SUCCESS */
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#include <sys/types.h> /* pid_t, DIR, struct dirent,
37
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ssize_t */
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#include <dirent.h> /* opendir(), readdir(), closedir() */
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#include <inttypes.h> /* intmax_t, strtoimax() */
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#include <sys/stat.h> /* struct stat, lstat(), S_ISLNK */
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#include <iso646.h> /* not, or, and */
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#include <unistd.h> /* readlink(), fork(), execl(),
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sleep(), dup2() STDERR_FILENO,
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STDOUT_FILENO, _exit() */
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STDOUT_FILENO, _exit(),
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pause() */
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#include <string.h> /* memcmp() */
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#include <errno.h> /* errno */
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#include <sys/wait.h> /* waitpid(), WIFEXITED(),
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WEXITSTATUS() */
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sig_atomic_t interrupted_by_signal = 0;
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int signal_received;
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static void termination_handler(__attribute__((unused))int signum){
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static void termination_handler(int signum){
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if(interrupted_by_signal){
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return;
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}
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interrupted_by_signal = 1;
58
signal_received = signum;
53
59
}
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60
55
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int main(__attribute__((unused))int argc,
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__attribute__((unused))char **argv){
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int ret = 0;
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char *prompt = NULL;
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DIR *proc_dir = NULL;
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pid_t splashy_pid = 0;
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pid_t splashy_command_pid = 0;
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68
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/* Create prompt string */
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char *prompt = NULL;
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{
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const char *const cryptsource = getenv("cryptsource");
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const char *const crypttarget = getenv("crypttarget");
80
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}
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}
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if(ret == -1){
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return EXIT_FAILURE;
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prompt = NULL;
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goto failure;
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}
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}
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/* Find splashy process */
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pid_t splashy_pid = 0;
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{
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const char splashy_name[] = "/sbin/splashy";
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DIR *proc_dir = opendir("/proc");
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proc_dir = opendir("/proc");
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if(proc_dir == NULL){
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free(prompt);
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perror("opendir");
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return EXIT_FAILURE;
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goto failure;
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}
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for(struct dirent *proc_ent = readdir(proc_dir);
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proc_ent != NULL;
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proc_ent = readdir(proc_dir)){
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pid_t pid = (pid_t) strtoul(proc_ent->d_name, NULL, 10);
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if(pid == 0){
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/* Not a process */
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continue;
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pid_t pid;
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{
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intmax_t tmpmax;
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char *tmp;
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errno = 0;
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tmpmax = strtoimax(proc_ent->d_name, &tmp, 10);
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if(errno != 0 or tmp == proc_ent->d_name or *tmp != '\0'
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or tmpmax != (pid_t)tmpmax){
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/* Not a process */
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continue;
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}
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pid = (pid_t)tmpmax;
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}
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/* Find the executable name by doing readlink() on the
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/proc/<pid>/exe link */
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ret = asprintf(&exe_link, "/proc/%s/exe", proc_ent->d_name);
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if(ret == -1){
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perror("asprintf");
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free(prompt);
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closedir(proc_dir);
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return EXIT_FAILURE;
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goto failure;
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131
}
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/* Check that it refers to a symlink owned by root:root */
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134
struct stat exe_stat;
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ret = lstat(exe_link, &exe_stat);
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if(ret == -1){
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if(errno == ENOENT){
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free(exe_link);
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continue;
140
}
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perror("lstat");
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free(exe_link);
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free(prompt);
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closedir(proc_dir);
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return EXIT_FAILURE;
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goto failure;
128
144
}
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if(not S_ISLNK(exe_stat.st_mode)
130
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or exe_stat.st_uid != 0
144
160
}
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}
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closedir(proc_dir);
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proc_dir = NULL;
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164
}
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if(splashy_pid == 0){
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free(prompt);
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return EXIT_FAILURE;
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goto failure;
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167
}
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/* Set up the signal handler */
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172
new_action = { .sa_handler = termination_handler,
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173
.sa_flags = 0 };
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sigemptyset(&new_action.sa_mask);
159
sigaddset(&new_action.sa_mask, SIGINT);
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sigaddset(&new_action.sa_mask, SIGHUP);
161
sigaddset(&new_action.sa_mask, SIGTERM);
175
ret = sigaddset(&new_action.sa_mask, SIGINT);
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if(ret == -1){
177
perror("sigaddset");
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goto failure;
179
}
180
ret = sigaddset(&new_action.sa_mask, SIGHUP);
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if(ret == -1){
182
perror("sigaddset");
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goto failure;
184
}
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ret = sigaddset(&new_action.sa_mask, SIGTERM);
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if(ret == -1){
187
perror("sigaddset");
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goto failure;
189
}
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190
ret = sigaction(SIGINT, NULL, &old_action);
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191
if(ret == -1){
164
192
perror("sigaction");
165
free(prompt);
166
return EXIT_FAILURE;
193
goto failure;
167
194
}
168
195
if(old_action.sa_handler != SIG_IGN){
169
196
ret = sigaction(SIGINT, &new_action, NULL);
170
197
if(ret == -1){
171
198
perror("sigaction");
172
free(prompt);
173
return EXIT_FAILURE;
199
goto failure;
174
200
}
175
201
}
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ret = sigaction(SIGHUP, NULL, &old_action);
177
203
if(ret == -1){
178
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perror("sigaction");
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free(prompt);
180
return EXIT_FAILURE;
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goto failure;
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206
}
182
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if(old_action.sa_handler != SIG_IGN){
183
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ret = sigaction(SIGHUP, &new_action, NULL);
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if(ret == -1){
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perror("sigaction");
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free(prompt);
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return EXIT_FAILURE;
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goto failure;
188
212
}
189
213
}
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ret = sigaction(SIGTERM, NULL, &old_action);
191
215
if(ret == -1){
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perror("sigaction");
193
free(prompt);
194
return EXIT_FAILURE;
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goto failure;
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218
}
196
219
if(old_action.sa_handler != SIG_IGN){
197
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ret = sigaction(SIGTERM, &new_action, NULL);
198
221
if(ret == -1){
199
222
perror("sigaction");
200
free(prompt);
201
return EXIT_FAILURE;
223
goto failure;
202
224
}
203
225
}
204
226
}
205
227
228
if(interrupted_by_signal){
229
goto failure;
230
}
231
206
232
/* Fork off the splashy command to prompt for password */
207
pid_t splashy_command_pid = 0;
208
if(not interrupted_by_signal){
209
splashy_command_pid = fork();
210
if(splashy_command_pid == -1){
211
if(not interrupted_by_signal){
212
perror("fork");
213
}
214
return EXIT_FAILURE;
215
}
216
/* Child */
217
if(splashy_command_pid == 0){
233
splashy_command_pid = fork();
234
if(splashy_command_pid != 0 and interrupted_by_signal){
235
goto failure;
236
}
237
if(splashy_command_pid == -1){
238
perror("fork");
239
goto failure;
240
}
241
/* Child */
242
if(splashy_command_pid == 0){
243
if(not interrupted_by_signal){
218
244
const char splashy_command[] = "/sbin/splashy_update";
219
ret = execl(splashy_command, splashy_command, prompt,
220
(char *)NULL);
221
if(not interrupted_by_signal){
222
perror("execl");
223
}
224
free(prompt);
225
_exit(EXIT_FAILURE);
245
execl(splashy_command, splashy_command, prompt, (char *)NULL);
246
perror("execl");
226
247
}
248
free(prompt);
249
_exit(EXIT_FAILURE);
227
250
}
228
251
229
252
/* Parent */
230
253
free(prompt);
254
prompt = NULL;
255
256
if(interrupted_by_signal){
257
goto failure;
258
}
231
259
232
260
/* Wait for command to complete */
233
if(not interrupted_by_signal and splashy_command_pid != 0){
261
{
234
262
int status;
235
ret = waitpid(splashy_command_pid, &status, 0);
263
do {
264
ret = waitpid(splashy_command_pid, &status, 0);
265
} while(ret == -1 and errno == EINTR
266
and not interrupted_by_signal);
267
if(interrupted_by_signal){
268
goto failure;
269
}
236
270
if(ret == -1){
237
if(errno != EINTR){
238
perror("waitpid");
239
}
271
perror("waitpid");
240
272
if(errno == ECHILD){
241
273
splashy_command_pid = 0;
242
274
}
243
275
} else {
244
276
/* The child process has exited */
245
277
splashy_command_pid = 0;
246
if(not interrupted_by_signal and WIFEXITED(status)
247
and WEXITSTATUS(status)==0){
278
if(WIFEXITED(status) and WEXITSTATUS(status) == 0){
248
279
return EXIT_SUCCESS;
249
280
}
250
281
}
251
282
}
252
kill(splashy_pid, SIGTERM);
253
if(interrupted_by_signal and splashy_command_pid != 0){
254
kill(splashy_command_pid, SIGTERM);
255
}
256
sleep(2);
257
while(kill(splashy_pid, 0) == 0){
258
kill(splashy_pid, SIGKILL);
259
sleep(1);
260
}
261
pid_t new_splashy_pid = fork();
262
if(new_splashy_pid == 0){
263
/* Child; will become new splashy process */
283
284
failure:
285
286
free(prompt);
287
288
if(proc_dir != NULL){
289
TEMP_FAILURE_RETRY(closedir(proc_dir));
290
}
291
292
if(splashy_command_pid != 0){
293
TEMP_FAILURE_RETRY(kill(splashy_command_pid, SIGTERM));
264
294
265
/* Make the effective user ID (root) the only user ID instead of
266
the real user ID (mandos) */
267
ret = setuid(geteuid());
268
if(ret == -1){
269
perror("setuid");
295
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGTERM));
296
sleep(2);
297
while(TEMP_FAILURE_RETRY(kill(splashy_pid, 0)) == 0){
298
TEMP_FAILURE_RETRY(kill(splashy_pid, SIGKILL));
299
sleep(1);
270
300
}
301
pid_t new_splashy_pid = (pid_t)TEMP_FAILURE_RETRY(fork());
302
if(new_splashy_pid == 0){
303
/* Child; will become new splashy process */
304
305
/* Make the effective user ID (root) the only user ID instead of
306
the real user ID (_mandos) */
307
ret = setuid(geteuid());
308
if(ret == -1){
309
perror("setuid");
310
}
311
312
setsid();
313
ret = chdir("/");
314
if(ret == -1){
315
perror("chdir");
316
}
317
/* if(fork() != 0){ */
318
/* _exit(EXIT_SUCCESS); */
319
/* } */
320
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace stdout */
321
if(ret == -1){
322
perror("dup2");
323
_exit(EXIT_FAILURE);
324
}
271
325
272
setsid();
273
ret = chdir("/");
274
/* if(fork() != 0){ */
275
/* _exit(EXIT_SUCCESS); */
276
/* } */
277
ret = dup2(STDERR_FILENO, STDOUT_FILENO); /* replace our stdout */
278
if(ret == -1){
279
perror("dup2");
326
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
327
perror("execl");
280
328
_exit(EXIT_FAILURE);
281
329
}
282
283
execl("/sbin/splashy", "/sbin/splashy", "boot", (char *)NULL);
284
if(not interrupted_by_signal){
285
perror("execl");
286
}
287
_exit(EXIT_FAILURE);
330
}
331
332
if(interrupted_by_signal){
333
struct sigaction signal_action;
334
sigemptyset(&signal_action.sa_mask);
335
signal_action.sa_handler = SIG_DFL;
336
ret = (int)TEMP_FAILURE_RETRY(sigaction(signal_received,
337
&signal_action, NULL));
338
if(ret == -1){
339
perror("sigaction");
340
}
341
do {
342
ret = raise(signal_received);
343
} while(ret != 0 and errno == EINTR);
344
if(ret != 0){
345
perror("raise");
346
abort();
347
}
348
TEMP_FAILURE_RETRY(pause());
288
349
}
289
350
290
351
return EXIT_FAILURE;
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