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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 <linux/loop.h>
#define MAX_READ 8192 // line buffer for profile files
static int initialized = 0;
static int cfg_val[CFG_MAX];
char *xephyr_screen = "800x600";
char *xephyr_extra_params = "";
char *xpra_extra_params = "";
char *xvfb_screen = "800x600x24";
char *xvfb_extra_params = "";
char *netfilter_default = NULL;
int checkcfg(int val) {
assert(val < CFG_MAX);
int line = 0;
FILE *fp = NULL;
char *ptr;
if (!initialized) {
// initialize defaults
int i;
for (i = 0; i < CFG_MAX; i++)
cfg_val[i] = 1; // most of them are enabled by default
cfg_val[CFG_RESTRICTED_NETWORK] = 0; // disabled by default
cfg_val[CFG_FORCE_NONEWPRIVS] = 0;
cfg_val[CFG_PRIVATE_BIN_NO_LOCAL] = 0;
cfg_val[CFG_FIREJAIL_PROMPT] = 0;
cfg_val[CFG_DISABLE_MNT] = 0;
cfg_val[CFG_ARP_PROBES] = DEFAULT_ARP_PROBES;
cfg_val[CFG_XPRA_ATTACH] = 0;
// open configuration file
const char *fname = SYSCONFDIR "/firejail.config";
fp = fopen(fname, "r");
if (!fp) {
#ifdef HAVE_GLOBALCFG
fprintf(stderr, "Error: Firejail configuration file %s not found\n", fname);
exit(1);
#else
initialized = 1;
return cfg_val[val];
#endif
}
// read configuration file
char buf[MAX_READ];
while (fgets(buf,MAX_READ, fp)) {
line++;
if (*buf == '#' || *buf == '\n')
continue;
// parse line
ptr = line_remove_spaces(buf);
if (!ptr)
continue;
// file transfer
else if (strncmp(ptr, "file-transfer ", 14) == 0) {
if (strcmp(ptr + 14, "yes") == 0)
cfg_val[CFG_FILE_TRANSFER] = 1;
else if (strcmp(ptr + 14, "no") == 0)
cfg_val[CFG_FILE_TRANSFER] = 0;
else
goto errout;
}
// dbus
else if (strncmp(ptr, "dbus ", 5) == 0) {
if (strcmp(ptr + 5, "yes") == 0)
cfg_val[CFG_DBUS] = 1;
else if (strcmp(ptr + 5, "no") == 0)
cfg_val[CFG_DBUS] = 0;
else
goto errout;
}
// join
else if (strncmp(ptr, "join ", 5) == 0) {
if (strcmp(ptr + 5, "yes") == 0)
cfg_val[CFG_JOIN] = 1;
else if (strcmp(ptr + 5, "no") == 0)
cfg_val[CFG_JOIN] = 0;
else
goto errout;
}
// x11
else if (strncmp(ptr, "x11 ", 4) == 0) {
if (strcmp(ptr + 4, "yes") == 0)
cfg_val[CFG_X11] = 1;
else if (strcmp(ptr + 4, "no") == 0)
cfg_val[CFG_X11] = 0;
else
goto errout;
}
// apparmor
else if (strncmp(ptr, "apparmor ", 9) == 0) {
if (strcmp(ptr + 9, "yes") == 0)
cfg_val[CFG_APPARMOR] = 1;
else if (strcmp(ptr + 9, "no") == 0)
cfg_val[CFG_APPARMOR] = 0;
else
goto errout;
}
// bind
else if (strncmp(ptr, "bind ", 5) == 0) {
if (strcmp(ptr + 5, "yes") == 0)
cfg_val[CFG_BIND] = 1;
else if (strcmp(ptr + 5, "no") == 0)
cfg_val[CFG_BIND] = 0;
else
goto errout;
}
// user namespace
else if (strncmp(ptr, "userns ", 7) == 0) {
if (strcmp(ptr + 7, "yes") == 0)
cfg_val[CFG_USERNS] = 1;
else if (strcmp(ptr + 7, "no") == 0)
cfg_val[CFG_USERNS] = 0;
else
goto errout;
}
// chroot
else if (strncmp(ptr, "chroot ", 7) == 0) {
if (strcmp(ptr + 7, "yes") == 0)
cfg_val[CFG_CHROOT] = 1;
else if (strcmp(ptr + 7, "no") == 0)
cfg_val[CFG_CHROOT] = 0;
else
goto errout;
}
// prompt
else if (strncmp(ptr, "firejail-prompt ", 16) == 0) {
if (strcmp(ptr + 16, "yes") == 0)
cfg_val[CFG_FIREJAIL_PROMPT] = 1;
else if (strcmp(ptr + 16, "no") == 0)
cfg_val[CFG_FIREJAIL_PROMPT] = 0;
else
goto errout;
}
// follow symlink as user
else if (strncmp(ptr, "follow-symlink-as-user ", 23) == 0) {
if (strcmp(ptr + 23, "yes") == 0)
cfg_val[CFG_FOLLOW_SYMLINK_AS_USER] = 1;
else if (strcmp(ptr + 23, "no") == 0)
cfg_val[CFG_FOLLOW_SYMLINK_AS_USER] = 0;
else
goto errout;
}
// nonewprivs
else if (strncmp(ptr, "force-nonewprivs ", 17) == 0) {
if (strcmp(ptr + 17, "yes") == 0)
cfg_val[CFG_FORCE_NONEWPRIVS] = 1;
else if (strcmp(ptr + 17, "no") == 0)
cfg_val[CFG_FORCE_NONEWPRIVS] = 0;
else
goto errout;
}
// seccomp
else if (strncmp(ptr, "seccomp ", 8) == 0) {
if (strcmp(ptr + 8, "yes") == 0)
cfg_val[CFG_SECCOMP] = 1;
else if (strcmp(ptr + 8, "no") == 0)
cfg_val[CFG_SECCOMP] = 0;
else
goto errout;
}
// whitelist
else if (strncmp(ptr, "whitelist ", 10) == 0) {
if (strcmp(ptr + 10, "yes") == 0)
cfg_val[CFG_WHITELIST] = 1;
else if (strcmp(ptr + 10, "no") == 0)
cfg_val[CFG_WHITELIST] = 0;
else
goto errout;
}
// network
else if (strncmp(ptr, "network ", 8) == 0) {
if (strcmp(ptr + 8, "yes") == 0)
cfg_val[CFG_NETWORK] = 1;
else if (strcmp(ptr + 8, "no") == 0)
cfg_val[CFG_NETWORK] = 0;
else
goto errout;
}
// network
else if (strncmp(ptr, "restricted-network ", 19) == 0) {
if (strcmp(ptr + 19, "yes") == 0)
cfg_val[CFG_RESTRICTED_NETWORK] = 1;
else if (strcmp(ptr + 19, "no") == 0)
cfg_val[CFG_RESTRICTED_NETWORK] = 0;
else
goto errout;
}
// netfilter
else if (strncmp(ptr, "netfilter-default ", 18) == 0) {
char *fname = ptr + 18;
while (*fname == ' ' || *fname == '\t')
ptr++;
char *end = strchr(fname, ' ');
if (end)
*end = '\0';
// is the file present?
struct stat s;
if (stat(fname, &s) == -1) {
fprintf(stderr, "Error: netfilter-default file %s not available\n", fname);
exit(1);
}
if (netfilter_default)
goto errout;
netfilter_default = strdup(fname);
if (!netfilter_default)
errExit("strdup");
if (arg_debug)
printf("netfilter default file %s\n", fname);
}
// Xephyr screen size
else if (strncmp(ptr, "xephyr-screen ", 14) == 0) {
// expecting two numbers and an x between them
int n1;
int n2;
int rv = sscanf(ptr + 14, "%dx%d", &n1, &n2);
if (rv != 2)
goto errout;
if (asprintf(&xephyr_screen, "%dx%d", n1, n2) == -1)
errExit("asprintf");
}
// xephyr window title
else if (strncmp(ptr, "xephyr-window-title ", 20) == 0) {
if (strcmp(ptr + 20, "yes") == 0)
cfg_val[CFG_XEPHYR_WINDOW_TITLE] = 1;
else if (strcmp(ptr + 20, "no") == 0)
cfg_val[CFG_XEPHYR_WINDOW_TITLE] = 0;
else
goto errout;
}
// Xephyr command extra parameters
else if (strncmp(ptr, "xephyr-extra-params ", 20) == 0) {
if (*xephyr_extra_params != '\0')
goto errout;
xephyr_extra_params = strdup(ptr + 20);
if (!xephyr_extra_params)
errExit("strdup");
}
// xpra server extra parameters
else if (strncmp(ptr, "xpra-extra-params ", 18) == 0) {
if (*xpra_extra_params != '\0')
goto errout;
xpra_extra_params = strdup(ptr + 18);
if (!xpra_extra_params)
errExit("strdup");
}
// Xvfb screen size
else if (strncmp(ptr, "xvfb-screen ", 12) == 0) {
// expecting three numbers separated by x's
unsigned int n1;
unsigned int n2;
unsigned int n3;
int rv = sscanf(ptr + 12, "%ux%ux%u", &n1, &n2, &n3);
if (rv != 3)
goto errout;
if (asprintf(&xvfb_screen, "%ux%ux%u", n1, n2, n3) == -1)
errExit("asprintf");
}
// Xvfb extra parameters
else if (strncmp(ptr, "xvfb-extra-params ", 18) == 0) {
if (*xvfb_extra_params != '\0')
goto errout;
xvfb_extra_params = strdup(ptr + 18);
if (!xvfb_extra_params)
errExit("strdup");
}
// quiet by default
else if (strncmp(ptr, "quiet-by-default ", 17) == 0) {
if (strcmp(ptr + 17, "yes") == 0)
arg_quiet = 1;
else if (strcmp(ptr + 17, "no") == 0)
arg_quiet = 0;
else
goto errout;
}
else if (strncmp(ptr, "overlayfs ", 10) == 0) {
if (strcmp(ptr + 10, "yes") == 0)
cfg_val[CFG_OVERLAYFS] = 1;
else if (strcmp(ptr + 10, "no") == 0)
cfg_val[CFG_OVERLAYFS] = 0;
else
goto errout;
}
else if (strncmp(ptr, "private-home ", 13) == 0) {
if (strcmp(ptr + 13, "yes") == 0)
cfg_val[CFG_PRIVATE_HOME] = 1;
else if (strcmp(ptr + 13, "no") == 0)
cfg_val[CFG_PRIVATE_HOME] = 0;
else
goto errout;
}
else if (strncmp(ptr, "private-lib ", 12) == 0) {
if (strcmp(ptr + 12, "yes") == 0)
cfg_val[CFG_PRIVATE_LIB] = 1;
else if (strcmp(ptr + 12, "no") == 0)
cfg_val[CFG_PRIVATE_LIB] = 0;
else
goto errout;
}
else if (strncmp(ptr, "chroot-desktop ", 15) == 0) {
if (strcmp(ptr + 15, "yes") == 0)
cfg_val[CFG_CHROOT_DESKTOP] = 1;
else if (strcmp(ptr + 15, "no") == 0)
cfg_val[CFG_CHROOT_DESKTOP] = 0;
else
goto errout;
}
else if (strncmp(ptr, "private-bin-no-local ", 21) == 0) {
if (strcmp(ptr + 21, "yes") == 0)
cfg_val[CFG_PRIVATE_BIN_NO_LOCAL] = 1;
else if (strcmp(ptr + 21, "no") == 0)
cfg_val[CFG_PRIVATE_BIN_NO_LOCAL] = 0;
else
goto errout;
}
else if (strncmp(ptr, "disable-mnt ", 12) == 0) {
if (strcmp(ptr + 12, "yes") == 0)
cfg_val[CFG_DISABLE_MNT] = 1;
else if (strcmp(ptr + 12, "no") == 0)
cfg_val[CFG_DISABLE_MNT] = 0;
else
goto errout;
}
// arp probes
else if (strncmp(ptr, "arp-probes ", 11) == 0) {
int arp_probes = atoi(ptr + 11);
if (arp_probes <= 1 || arp_probes > 30)
goto errout;
cfg_val[CFG_ARP_PROBES] = arp_probes;
}
// xpra-attach
else if (strncmp(ptr, "xpra-attach ", 12) == 0) {
if (strcmp(ptr + 12, "yes") == 0)
cfg_val[CFG_XPRA_ATTACH] = 1;
else if (strcmp(ptr + 12, "no") == 0)
cfg_val[CFG_XPRA_ATTACH] = 0;
else
goto errout;
}
else
goto errout;
free(ptr);
}
fclose(fp);
initialized = 1;
}
return cfg_val[val];
errout:
assert(ptr);
free(ptr);
assert(fp);
fclose(fp);
fprintf(stderr, "Error: invalid line %d in firejail configuration file\n", line );
exit(1);
}
void print_compiletime_support(void) {
printf("Compile time support:\n");
printf("\t- AppArmor support is %s\n",
#ifdef HAVE_APPARMOR
"enabled"
#else
"disabled"
#endif
);
printf("\t- AppImage support is %s\n",
#ifdef LOOP_CTL_GET_FREE // test for older kernels; this definition is found in /usr/include/linux/loop.h
"enabled"
#else
"disabled"
#endif
);
printf("\t- bind support is %s\n",
#ifdef HAVE_BIND
"enabled"
#else
"disabled"
#endif
);
printf("\t- chroot support is %s\n",
#ifdef HAVE_CHROOT
"enabled"
#else
"disabled"
#endif
);
printf("\t- file and directory whitelisting support is %s\n",
#ifdef HAVE_WHITELIST
"enabled"
#else
"disabled"
#endif
);
printf("\t- file transfer support is %s\n",
#ifdef HAVE_FILE_TRANSFER
"enabled"
#else
"disabled"
#endif
);
printf("\t- networking support is %s\n",
#ifdef HAVE_NETWORK
"enabled"
#else
"disabled"
#endif
);
#ifdef HAVE_NETWORK_RESTRICTED
printf("\t- networking features are available only to root user\n");
#endif
printf("\t- overlayfs support is %s\n",
#ifdef HAVE_OVERLAYFS
"enabled"
#else
"disabled"
#endif
);
printf("\t- private-home support is %s\n",
#ifdef HAVE_PRIVATE_HOME
"enabled"
#else
"disabled"
#endif
);
printf("\t- seccomp-bpf support is %s\n",
#ifdef HAVE_SECCOMP
"enabled"
#else
"disabled"
#endif
);
printf("\t- user namespace support is %s\n",
#ifdef HAVE_USERNS
"enabled"
#else
"disabled"
#endif
);
printf("\t- X11 sandboxing support is %s\n",
#ifdef HAVE_X11
"enabled"
#else
"disabled"
#endif
);
printf("\t- Wireless interface support is %s\n",
#ifdef IPVLAN_MODE_L2
"enabled"
#else
"disabled"
#endif
);
}
|