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/*
* Copyright (C) 2014-2021 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 "../include/seccomp.h"
#include "../include/syscall.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;
unsigned long join_timeout = 5000000; // microseconds
char *config_seccomp_error_action_str = "EPERM";
char *config_seccomp_filter_add = NULL;
char **whitelist_reject_topdirs = 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;
cfg_val[CFG_SECCOMP_ERROR_ACTION] = -1;
cfg_val[CFG_BROWSER_ALLOW_DRM] = 0;
// open configuration file
const char *fname = SYSCONFDIR "/firejail.config";
fp = fopen(fname, "re");
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;
#define PARSE_YESNO(key, string) \
else if (strncmp(ptr, string " ", strlen(string)+1) == 0) { \
if (strcmp(ptr + strlen(string) + 1, "yes") == 0) \
cfg_val[key] = 1; \
else if (strcmp(ptr + strlen(string) + 1, "no") == 0) \
cfg_val[key] = 0; \
else \
goto errout; \
}
// parse line
ptr = line_remove_spaces(buf);
if (!ptr)
continue;
PARSE_YESNO(CFG_FILE_TRANSFER, "file-transfer")
PARSE_YESNO(CFG_DBUS, "dbus")
PARSE_YESNO(CFG_JOIN, "join")
PARSE_YESNO(CFG_X11, "x11")
PARSE_YESNO(CFG_APPARMOR, "apparmor")
PARSE_YESNO(CFG_BIND, "bind")
PARSE_YESNO(CFG_CGROUP, "cgroup")
PARSE_YESNO(CFG_NAME_CHANGE, "name-change")
PARSE_YESNO(CFG_USERNS, "userns")
PARSE_YESNO(CFG_CHROOT, "chroot")
PARSE_YESNO(CFG_FIREJAIL_PROMPT, "firejail-prompt")
PARSE_YESNO(CFG_FORCE_NONEWPRIVS, "force-nonewprivs")
PARSE_YESNO(CFG_SECCOMP, "seccomp")
PARSE_YESNO(CFG_WHITELIST, "whitelist")
PARSE_YESNO(CFG_NETWORK, "network")
PARSE_YESNO(CFG_RESTRICTED_NETWORK, "restricted-network")
PARSE_YESNO(CFG_XEPHYR_WINDOW_TITLE, "xephyr-window-title")
PARSE_YESNO(CFG_OVERLAYFS, "overlayfs")
PARSE_YESNO(CFG_PRIVATE_BIN, "private-bin")
PARSE_YESNO(CFG_PRIVATE_BIN_NO_LOCAL, "private-bin-no-local")
PARSE_YESNO(CFG_PRIVATE_CACHE, "private-cache")
PARSE_YESNO(CFG_PRIVATE_ETC, "private-etc")
PARSE_YESNO(CFG_PRIVATE_HOME, "private-home")
PARSE_YESNO(CFG_PRIVATE_LIB, "private-lib")
PARSE_YESNO(CFG_PRIVATE_OPT, "private-opt")
PARSE_YESNO(CFG_PRIVATE_SRV, "private-srv")
PARSE_YESNO(CFG_DISABLE_MNT, "disable-mnt")
PARSE_YESNO(CFG_XPRA_ATTACH, "xpra-attach")
PARSE_YESNO(CFG_BROWSER_DISABLE_U2F, "browser-disable-u2f")
PARSE_YESNO(CFG_BROWSER_ALLOW_DRM, "browser-allow-drm")
#undef PARSE_YESNO
// 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?
if (access(fname, F_OK) == -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 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;
}
// 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;
}
// file copy limit
else if (strncmp(ptr, "file-copy-limit ", 16) == 0)
env_store_name_val("FIREJAIL_FILE_COPY_LIMIT", ptr + 16, SETENV);
// timeout for join option
else if (strncmp(ptr, "join-timeout ", 13) == 0)
join_timeout = strtoul(ptr + 13, NULL, 10) * 1000000; // seconds to microseconds
// add rules to default seccomp filter
else if (strncmp(ptr, "seccomp-filter-add ", 19) == 0)
config_seccomp_filter_add = seccomp_check_list(ptr + 19);
// seccomp error action
else if (strncmp(ptr, "seccomp-error-action ", 21) == 0) {
if (strcmp(ptr + 21, "kill") == 0)
cfg_val[CFG_SECCOMP_ERROR_ACTION] = SECCOMP_RET_KILL;
else if (strcmp(ptr + 21, "log") == 0)
cfg_val[CFG_SECCOMP_ERROR_ACTION] = SECCOMP_RET_LOG;
else {
cfg_val[CFG_SECCOMP_ERROR_ACTION] = errno_find_name(ptr + 21);
if (cfg_val[CFG_SECCOMP_ERROR_ACTION] == -1)
errExit("seccomp-error-action: unknown errno");
}
config_seccomp_error_action_str = strdup(ptr + 21);
if (!config_seccomp_error_action_str)
errExit("strdup");
}
else if (strncmp(ptr, "whitelist-disable-topdir ", 25) == 0) {
char *str = strdup(ptr + 25);
if (!str)
errExit("strdup");
size_t cnt = 0;
size_t sz = 4;
whitelist_reject_topdirs = malloc(sz * sizeof(char *));
if (!whitelist_reject_topdirs)
errExit("malloc");
char *tok = strtok(str, ",");
while (tok) {
whitelist_reject_topdirs[cnt++] = tok;
if (cnt >= sz) {
sz *= 2;
whitelist_reject_topdirs = realloc(whitelist_reject_topdirs, sz * sizeof(char *));
if (!whitelist_reject_topdirs)
errExit("realloc");
}
tok = strtok(NULL, ",");
}
whitelist_reject_topdirs[cnt] = NULL;
}
else
goto errout;
free(ptr);
}
fclose(fp);
initialized = 1;
}
// merge CFG_RESTRICTED_NETWORK into CFG_NETWORK
if (val == CFG_NETWORK) {
if (cfg_val[CFG_RESTRICTED_NETWORK] && getuid() != 0)
return 0;
}
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- always force nonewprivs support is %s\n",
#ifdef HAVE_FORCE_NONEWPRIVS
"enabled"
#else
"disabled"
#endif
);
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- chroot support is %s\n",
#ifdef HAVE_CHROOT
"enabled"
#else
"disabled"
#endif
);
printf("\t- D-BUS proxy support is %s\n",
#ifdef HAVE_DBUSPROXY
"enabled"
#else
"disabled"
#endif
);
printf("\t- file transfer support is %s\n",
#ifdef HAVE_FILE_TRANSFER
"enabled"
#else
"disabled"
#endif
);
printf("\t- firetunnel support is %s\n",
#ifdef HAVE_FIRETUNNEL
"enabled"
#else
"disabled"
#endif
);
printf("\t- networking support is %s\n",
#ifdef HAVE_NETWORK
"enabled"
#else
"disabled"
#endif
);
printf("\t- output logging is %s\n",
#ifdef HAVE_OUTPUT
"enabled"
#else
"disabled"
#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- private-cache and tmpfs as user %s\n",
#ifdef HAVE_USERTMPFS
"enabled"
#else
"disabled"
#endif
);
printf("\t- SELinux support is %s\n",
#ifdef HAVE_SELINUX
"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
);
}
|