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/*
* Copyright (C) 2014-2018 Firejail Authors
*
* This file is part of firejail project
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "firejail.h"
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <sys/prctl.h>
void shut(pid_t pid) {
EUID_ASSERT();
pid_t parent = pid;
// if the pid is that of a firejail process, use the pid of a child process inside the sandbox
EUID_ROOT();
char *comm = pid_proc_comm(pid);
EUID_USER();
if (comm) {
if (strcmp(comm, "firejail") == 0) {
pid_t child;
if (find_child(pid, &child) == 0) {
pid = child;
printf("Switching to pid %u, the first child process inside the sandbox\n", (unsigned) pid);
}
}
else {
fprintf(stderr, "Error: this is not a firejail sandbox\n");
exit(1);
}
free(comm);
}
else
errExit("/proc/PID/comm");
// check privileges for non-root users
uid_t uid = getuid();
if (uid != 0) {
uid_t sandbox_uid = pid_get_uid(pid);
if (uid != sandbox_uid) {
fprintf(stderr, "Error: permission is denied to shutdown a sandbox created by a different user.\n");
exit(1);
}
}
EUID_ROOT();
printf("Sending SIGTERM to %u\n", pid);
kill(pid, SIGTERM);
// wait for not more than 10 seconds
sleep(2);
int monsec = 8;
char *monfile;
if (asprintf(&monfile, "/proc/%d/cmdline", pid) == -1)
errExit("asprintf");
int killdone = 0;
while (monsec) {
FILE *fp = fopen(monfile, "r");
if (!fp) {
killdone = 1;
break;
}
char c;
size_t count = fread(&c, 1, 1, fp);
fclose(fp);
if (count == 0) {
// all done
killdone = 1;
break;
}
sleep(1);
monsec--;
}
free(monfile);
// force SIGKILL
if (!killdone) {
// kill the process and also the parent
printf("Sending SIGKILL to %u\n", pid);
kill(pid, SIGKILL);
if (parent != pid) {
printf("Sending SIGKILL to %u\n", parent);
kill(parent, SIGKILL);
}
}
clear_run_files(parent);
}
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