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/*
* Copyright (C) 2014-2019 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"
#include <linux/capability.h>
#define MAXBUF 4098
static int extract_caps(uint64_t *val) {
FILE *fp = fopen("/proc/self/status", "r");
if (!fp)
return 1;
char buf[MAXBUF];
while (fgets(buf, MAXBUF, fp)) {
if (strncmp(buf, "CapBnd:\t", 8) == 0) {
char *ptr = buf + 8;
unsigned long long tmp;
sscanf(ptr, "%llx", &tmp);
*val = tmp;
fclose(fp);
return 0;
}
}
fclose(fp);
return 1;
}
// return 1 if the capability is in the map
static int check_capability(uint64_t map, int cap) {
int i;
uint64_t mask = 1ULL;
for (i = 0; i < 64; i++, mask <<= 1) {
if ((i == cap) && (mask & map))
return 1;
}
return 0;
}
void caps_test(void) {
uint64_t caps_val;
if (extract_caps(&caps_val)) {
printf("SKIP: cannot extract capabilities on this platform.\n");
return;
}
if (caps_val) {
printf("BAD: the capability map is %llx, it should be all zero. ", (unsigned long long) caps_val);
printf("Use \"firejail --caps.drop=all\" to fix it.\n");
if (check_capability(caps_val, CAP_SYS_ADMIN))
printf("UGLY: CAP_SYS_ADMIN is enabled.\n");
if (check_capability(caps_val, CAP_SYS_BOOT))
printf("UGLY: CAP_SYS_BOOT is enabled.\n");
}
else
printf("GOOD: all capabilities are disabled.\n");
}
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