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/*
* Copyright (C) 2014-2016 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 "faudit.h"
#define MAXBUF 4098
static int extract_seccomp(int *val) {
FILE *fp = fopen("/proc/self/status", "r");
if (!fp)
return 1;
char buf[MAXBUF];
while (fgets(buf, MAXBUF, fp)) {
if (strncmp(buf, "Seccomp:\t", 8) == 0) {
char *ptr = buf + 8;
int tmp;
sscanf(ptr, "%d", &tmp);
*val = tmp;
fclose(fp);
return 0;
}
}
fclose(fp);
return 1;
}
void seccomp_test(void) {
int seccomp_status;
int rv = extract_seccomp(&seccomp_status);
if (rv) {
printf("SKIP: cannot extract seccomp configuration on this platform\n");
return;
}
if (seccomp_status == 0) {
printf("BAD: seccomp disabled\n");
printf("Use \"firejail --seccomp\" to fix it.\n");
}
else if (seccomp_status == 1)
printf("GOOD: seccomp strict mode - only read, write, _exit, and sigreturn are allowd\n");
else if (seccomp_status == 2) {
printf("GOOD: seccomp BPF enababled\n");
printf("checking syscalls: "); fflush(0);
printf("mount... "); fflush(0);
syscall_run("mount");
printf("umount2... "); fflush(0);
syscall_run("umount2");
printf("ptrace... "); fflush(0);
syscall_run("ptrace");
printf("swapon... "); fflush(0);
syscall_run("swapon");
printf("swapoff... "); fflush(0);
syscall_run("swapoff");
printf("init_module... "); fflush(0);
syscall_run("init_module");
printf("finit_module... "); fflush(0);
syscall_run("finit_module");
printf("delete_module... "); fflush(0);
syscall_run("delete_module");
printf("chroot... "); fflush(0);
syscall_run("chroot");
printf("pivot_root... "); fflush(0);
syscall_run("pivot_root");
printf("iopl... "); fflush(0);
syscall_run("iopl");
printf("ioperm... "); fflush(0);
syscall_run("ioperm");
printf("\n");
}
else
fprintf(stderr, "Error: unrecognized seccomp mode\n");
}
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