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sandbox.c
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sandbox.c
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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 <sys/mman.h>
#include <sys/mount.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <syscall.h>
#include <sched.h>
#ifndef CLONE_NEWUSER
#define CLONE_NEWUSER 0x10000000
#endif
#include <sys/prctl.h>
#ifndef PR_SET_NO_NEW_PRIVS
#define PR_SET_NO_NEW_PRIVS 38
#endif
#ifndef PR_GET_NO_NEW_PRIVS
#define PR_GET_NO_NEW_PRIVS 39
#endif
#ifdef HAVE_APPARMOR
#include <sys/apparmor.h>
#endif
static int force_nonewprivs = 0;
static int monitored_pid = 0;
static void sandbox_handler(int sig){
usleep(10000); // don't race to print a message
fmessage("\nChild received signal %d, shutting down the sandbox...\n", sig);
// broadcast sigterm to all processes in the group
kill(-1, SIGTERM);
sleep(1);
if (monitored_pid) {
int monsec = 9;
char *monfile;
if (asprintf(&monfile, "/proc/%d/cmdline", monitored_pid) == -1)
errExit("asprintf");
while (monsec) {
FILE *fp = fopen(monfile, "r");
if (!fp)
break;
char c;
size_t count = fread(&c, 1, 1, fp);
fclose(fp);
if (count == 0)
break;
if (arg_debug)
printf("Waiting on PID %d to finish\n", monitored_pid);
sleep(1);
monsec--;
}
free(monfile);
}
// broadcast a SIGKILL
kill(-1, SIGKILL);
flush_stdin();
exit(sig);
}
static void install_handler(void) {
struct sigaction sga;
// block SIGTERM while handling SIGINT
sigemptyset(&sga.sa_mask);
sigaddset(&sga.sa_mask, SIGTERM);
sga.sa_handler = sandbox_handler;
sga.sa_flags = 0;
sigaction(SIGINT, &sga, NULL);
// block SIGINT while handling SIGTERM
sigemptyset(&sga.sa_mask);
sigaddset(&sga.sa_mask, SIGINT);
sga.sa_handler = sandbox_handler;
sga.sa_flags = 0;
sigaction(SIGTERM, &sga, NULL);
}
static void set_caps(void) {
if (arg_caps_drop_all)
caps_drop_all();
else if (arg_caps_drop)
caps_drop_list(arg_caps_list);
else if (arg_caps_keep)
caps_keep_list(arg_caps_list);
else if (arg_caps_default_filter)
caps_default_filter();
// drop discretionary access control capabilities for root sandboxes
// if caps.keep, the user has to set it manually in the list
if (!arg_caps_keep)
caps_drop_dac_override();
}
#ifdef HAVE_APPARMOR
void set_apparmor(void) {
EUID_ASSERT();
if (checkcfg(CFG_APPARMOR) && arg_apparmor) {
if (aa_change_onexec("firejail-default")) {
fwarning("Cannot confine the application using AppArmor.\n"
"Maybe firejail-default AppArmor profile is not loaded into the kernel.\n"
"As root, run \"aa-enforce firejail-default\" to load it.\n");
}
else if (arg_debug)
printf("AppArmor enabled\n");
}
}
#endif
static void seccomp_debug(void) {
if (arg_debug == 0)
return;
EUID_USER();
printf("Seccomp directory:\n");
ls(RUN_SECCOMP_DIR);
struct stat s;
if (stat(RUN_SECCOMP_LIST, &s) == 0) {
printf("Active seccomp files:\n");
cat(RUN_SECCOMP_LIST);
}
else
printf("No active seccomp files\n");
EUID_ROOT();
}
static void save_nogroups(void) {
if (arg_nogroups == 0)
return;
FILE *fp = fopen(RUN_GROUPS_CFG, "w");
if (fp) {
fprintf(fp, "\n");
SET_PERMS_STREAM(fp, 0, 0, 0644); // assume mode 0644
fclose(fp);
}
else {
fprintf(stderr, "Error: cannot save nogroups state\n");
exit(1);
}
}
static void save_nonewprivs(void) {
if (arg_nonewprivs == 0)
return;
FILE *fp = fopen(RUN_NONEWPRIVS_CFG, "wxe");
if (fp) {
fprintf(fp, "\n");
SET_PERMS_STREAM(fp, 0, 0, 0644); // assume mode 0644
fclose(fp);
}
else {
fprintf(stderr, "Error: cannot save nonewprivs state\n");
exit(1);
}
}
static void save_umask(void) {
FILE *fp = fopen(RUN_UMASK_FILE, "wxe");
if (fp) {
fprintf(fp, "%o\n", orig_umask);
SET_PERMS_STREAM(fp, 0, 0, 0644); // assume mode 0644
fclose(fp);
}
else {
fprintf(stderr, "Error: cannot save umask\n");
exit(1);
}
}
static char *create_join_file(void) {
int fd = open(RUN_JOIN_FILE, O_RDWR|O_CREAT|O_EXCL|O_CLOEXEC, S_IRUSR | S_IWRITE | S_IRGRP | S_IROTH);
if (fd == -1)
errExit("open");
if (ftruncate(fd, 1) == -1)
errExit("ftruncate");
char *rv = mmap(NULL, 1, PROT_WRITE, MAP_SHARED, fd, 0);
if (rv == MAP_FAILED)
errExit("mmap");
close(fd);
return rv;
}
static void sandbox_if_up(Bridge *br) {
assert(br);
if (!br->configured)
return;
char *dev = br->devsandbox;
net_if_up(dev);
if (br->arg_ip_none == 1); // do nothing
else if (br->arg_ip_none == 0 && br->macvlan == 0) {
if (br->ipsandbox == br->ip) {
fprintf(stderr, "Error: %d.%d.%d.%d is interface %s address.\n", PRINT_IP(br->ipsandbox), br->dev);
exit(1);
}
// just assign the address
assert(br->ipsandbox);
if (arg_debug)
printf("Configuring %d.%d.%d.%d address on interface %s\n", PRINT_IP(br->ipsandbox), dev);
net_config_interface(dev, br->ipsandbox, br->mask, br->mtu);
arp_announce(dev, br);
}
else if (br->arg_ip_none == 0 && br->macvlan == 1) {
// reassign the macvlan address
if (br->ipsandbox == 0)
// ip address assigned by arp-scan for a macvlan device
br->ipsandbox = arp_assign(dev, br); //br->ip, br->mask);
else {
if (br->ipsandbox == br->ip) {
fprintf(stderr, "Error: %d.%d.%d.%d is interface %s address.\n", PRINT_IP(br->ipsandbox), br->dev);
exit(1);
}
uint32_t rv = arp_check(dev, br->ipsandbox);
if (rv) {
fprintf(stderr, "Error: the address %d.%d.%d.%d is already in use.\n", PRINT_IP(br->ipsandbox));
exit(1);
}
}
if (arg_debug)
printf("Configuring %d.%d.%d.%d address on interface %s\n", PRINT_IP(br->ipsandbox), dev);
net_config_interface(dev, br->ipsandbox, br->mask, br->mtu);
arp_announce(dev, br);
}
if (br->ip6sandbox)
net_if_ip6(dev, br->ip6sandbox);
}
static void chk_chroot(void) {
// if we are starting firejail inside some other container technology, we don't care about this
if (env_get("container"))
return;
// check if this is a regular chroot
struct stat s;
if (stat("/", &s) == 0) {
if (s.st_ino != 2)
return;
}
fprintf(stderr, "Error: cannot mount filesystem as slave\n");
exit(1);
}
static int monitor_application(pid_t app_pid) {
EUID_ASSERT();
monitored_pid = app_pid;
// block signals and install handler
sigset_t oldmask, newmask;
sigemptyset(&oldmask);
sigemptyset(&newmask);
sigaddset(&newmask, SIGTERM);
sigaddset(&newmask, SIGINT);
sigprocmask(SIG_BLOCK, &newmask, &oldmask);
install_handler();
// handle --timeout
int options = 0;;
unsigned timeout = 0;
if (cfg.timeout) {
options = WNOHANG;
timeout = cfg.timeout;
sleep(1);
}
int status = 0;
int app_status = 0;
while (monitored_pid) {
usleep(20000);
char *msg;
if (asprintf(&msg, "monitoring pid %d\n", monitored_pid) == -1)
errExit("asprintf");
logmsg(msg);
if (arg_debug)
printf("%s\n", msg);
free(msg);
pid_t rv;
do {
// handle signals asynchronously
sigprocmask(SIG_SETMASK, &oldmask, NULL);
rv = waitpid(-1, &status, options);
// block signals again
sigprocmask(SIG_BLOCK, &newmask, NULL);
if (rv == -1) { // we can get here if we have processes joining the sandbox (ECHILD)
sleep(1);
break;
}
else if (rv == app_pid)
app_status = status;
// handle --timeout
if (options) {
if (--timeout == 0) {
// SIGTERM might fail if the process ignores it (SIG_IGN)
// we give it 100ms to close properly and after that we SIGKILL it
kill(-1, SIGTERM);
usleep(100000);
kill(-1, SIGKILL);
flush_stdin();
_exit(1);
}
else
sleep(1);
}
}
while(rv != monitored_pid);
if (arg_debug)
printf("Sandbox monitor: waitpid %d retval %d status %d\n", monitored_pid, rv, status);
DIR *dir;
if (!(dir = opendir("/proc"))) {
// sleep 2 seconds and try again
sleep(2);
if (!(dir = opendir("/proc"))) {
fprintf(stderr, "Error: cannot open /proc directory\n");
exit(1);
}
}
struct dirent *entry;
monitored_pid = 0;
while ((entry = readdir(dir)) != NULL) {
unsigned pid;
if (sscanf(entry->d_name, "%u", &pid) != 1)
continue;
if (pid == 1)
continue;
if ((pid_t) pid == dhclient4_pid || (pid_t) pid == dhclient6_pid)
continue;
// todo: make this generic
// Dillo browser leaves a dpid process running, we need to shut it down
int found = 0;
if (strcmp(cfg.command_name, "dillo") == 0) {
char *pidname = pid_proc_comm(pid);
if (pidname && strcmp(pidname, "dpid") == 0)
found = 1;
free(pidname);
}
if (found)
break;
monitored_pid = pid;
break;
}
closedir(dir);
if (monitored_pid != 0 && arg_debug)
printf("Sandbox monitor: monitoring %d\n", monitored_pid);
}
// return the appropriate exit status.
return arg_deterministic_exit_code ? app_status : status;
}
static void print_time(void) {
float delta = timetrace_end();
fmessage("Child process initialized in %.02f ms\n", delta);
}
// check execute permissions for the program
// this is done typically by the shell
// we are here because of --shell=none
// we duplicate execvp functionality (man execvp):
// [...] if the specified
// filename does not contain a slash (/) character. The file is sought
// in the colon-separated list of directory pathnames specified in the
// PATH environment variable.
static int ok_to_run(const char *program) {
if (strstr(program, "/")) {
if (access(program, X_OK) == 0) // it will also dereference symlinks
return 1;
}
else { // search $PATH
const char *path1 = env_get("PATH");
if (path1) {
if (arg_debug)
printf("Searching $PATH for %s\n", program);
char *path2 = strdup(path1);
if (!path2)
errExit("strdup");
// use path2 to count the entries
char *ptr = strtok(path2, ":");
while (ptr) {
char *fname;
if (asprintf(&fname, "%s/%s", ptr, program) == -1)
errExit("asprintf");
if (arg_debug)
printf("trying #%s#\n", fname);
struct stat s;
int rv = stat(fname, &s);
if (rv == 0) {
if (access(fname, X_OK) == 0) {
free(path2);
free(fname);
return 1;
}
else
fprintf(stderr, "Error: execute permission denied for %s\n", fname);
free(fname);
break;
}
free(fname);
ptr = strtok(NULL, ":");
}
free(path2);
}
}
return 0;
}
void start_application(int no_sandbox, int fd, char *set_sandbox_status) {
// set environment
if (no_sandbox == 0)
env_defaults();
env_apply_all();
// restore original umask
umask(orig_umask);
if (arg_debug) {
printf("Starting application\n");
printf("LD_PRELOAD=%s\n", getenv("LD_PRELOAD"));
}
//****************************************
// audit
//****************************************
if (arg_audit) {
assert(arg_audit_prog);
#ifdef HAVE_GCOV
__gcov_dump();
#endif
seccomp_install_filters();
if (set_sandbox_status)
*set_sandbox_status = SANDBOX_DONE;
execl(arg_audit_prog, arg_audit_prog, NULL);
}
//****************************************
// start the program without using a shell
//****************************************
else if (arg_shell_none) {
if (arg_debug) {
int i;
for (i = cfg.original_program_index; i < cfg.original_argc; i++) {
if (cfg.original_argv[i] == NULL)
break;
printf("execvp argument %d: %s\n", i - cfg.original_program_index, cfg.original_argv[i]);
}
}
if (cfg.original_program_index == 0) {
fprintf(stderr, "Error: --shell=none configured, but no program specified\n");
exit(1);
}
if (!arg_command && !arg_quiet)
print_time();
if (ok_to_run(cfg.original_argv[cfg.original_program_index]) == 0) {
fprintf(stderr, "Error: no suitable %s executable found\n", cfg.original_argv[cfg.original_program_index]);
exit(1);
}
#ifdef HAVE_GCOV
__gcov_dump();
#endif
seccomp_install_filters();
if (set_sandbox_status)
*set_sandbox_status = SANDBOX_DONE;
execvp(cfg.original_argv[cfg.original_program_index], &cfg.original_argv[cfg.original_program_index]);
}
//****************************************
// start the program using a shell
//****************************************
else {
assert(cfg.shell);
char *arg[5];
int index = 0;
arg[index++] = cfg.shell;
if (cfg.command_line) {
if (arg_debug)
printf("Running %s command through %s\n", cfg.command_line, cfg.shell);
arg[index++] = "-c";
if (arg_doubledash)
arg[index++] = "--";
arg[index++] = cfg.command_line;
}
else if (login_shell) {
if (arg_debug)
printf("Starting %s login shell\n", cfg.shell);
arg[index++] = "-l";
}
else if (arg_debug)
printf("Starting %s shell\n", cfg.shell);
assert(index < 5);
arg[index] = NULL;
if (arg_debug) {
char *msg;
if (asprintf(&msg, "sandbox %d, execvp into %s",
sandbox_pid, cfg.command_line ? cfg.command_line : cfg.shell) == -1)
errExit("asprintf");
logmsg(msg);
free(msg);
int i;
for (i = 0; i < 5; i++) {
if (arg[i] == NULL)
break;
printf("execvp argument %d: %s\n", i, arg[i]);
}
}
if (!arg_command && !arg_quiet)
print_time();
#ifdef HAVE_GCOV
__gcov_dump();
#endif
seccomp_install_filters();
if (set_sandbox_status)
*set_sandbox_status = SANDBOX_DONE;
execvp(arg[0], arg);
// join sandbox without shell in the mount namespace
if (fd > -1)
fexecve(fd, arg, environ);
}
perror("Cannot start application");
exit(1);
}
static void enforce_filters(void) {
// enforce NO_NEW_PRIVS
arg_nonewprivs = 1;
force_nonewprivs = 1;
// disable all capabilities
fmessage("\n** Warning: dropping all Linux capabilities **\n\n");
arg_caps_drop_all = 1;
// drop all supplementary groups; /etc/group file inside chroot
// is controlled by a regular usr
arg_nogroups = 1;
}
int sandbox(void* sandbox_arg) {
// Get rid of unused parameter warning
(void)sandbox_arg;
pid_t child_pid = getpid();
if (arg_debug)
printf("Initializing child process\n");
// close each end of the unused pipes
close(parent_to_child_fds[1]);
close(child_to_parent_fds[0]);
// wait for parent to do base setup
wait_for_other(parent_to_child_fds[0]);
if (arg_debug && child_pid == 1)
printf("PID namespace installed\n");
//****************************
// set hostname
//****************************
if (cfg.hostname) {
if (sethostname(cfg.hostname, strlen(cfg.hostname)) < 0)
errExit("sethostname");
}
//****************************
// mount namespace
//****************************
// mount events are not forwarded between the host the sandbox
if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL) < 0) {
chk_chroot();
}
// ... and mount a tmpfs on top of /run/firejail/mnt directory
preproc_mount_mnt_dir();
// bind-mount firejail binaries and helper programs
if (mount(LIBDIR "/firejail", RUN_FIREJAIL_LIB_DIR, NULL, MS_BIND, NULL) < 0 ||
mount(NULL, RUN_FIREJAIL_LIB_DIR, NULL, MS_RDONLY|MS_NOSUID|MS_NODEV|MS_BIND|MS_REMOUNT, NULL) < 0)
errExit("mounting " RUN_FIREJAIL_LIB_DIR);
// keep a copy of dhclient executable before the filesystem is modified
dhcp_store_exec();
//****************************
// log sandbox data
//****************************
if (cfg.name)
fs_logger2("sandbox name:", cfg.name);
fs_logger2int("sandbox pid:", (int) sandbox_pid);
if (cfg.chrootdir)
fs_logger("sandbox filesystem: chroot");
else if (arg_overlay)
fs_logger("sandbox filesystem: overlay");
else
fs_logger("sandbox filesystem: local");
fs_logger("install mount namespace");
//****************************
// netfilter
//****************************
if (arg_netfilter && any_bridge_configured()) { // assuming by default the client filter
netfilter(arg_netfilter_file);
}
if (arg_netfilter6 && any_bridge_configured()) { // assuming by default the client filter
netfilter6(arg_netfilter6_file);
}
//****************************
// networking
//****************************
int gw_cfg_failed = 0; // default gw configuration flag
if (arg_nonetwork) {
net_if_up("lo");
if (arg_debug)
printf("Network namespace enabled, only loopback interface available\n");
}
else if (arg_netns) {
netns(arg_netns);
if (arg_debug)
printf("Network namespace '%s' activated\n", arg_netns);
}
else if (any_bridge_configured() || any_interface_configured()) {
// configure lo and eth0...eth3
net_if_up("lo");
if (mac_not_zero(cfg.bridge0.macsandbox))
net_config_mac(cfg.bridge0.devsandbox, cfg.bridge0.macsandbox);
sandbox_if_up(&cfg.bridge0);
if (mac_not_zero(cfg.bridge1.macsandbox))
net_config_mac(cfg.bridge1.devsandbox, cfg.bridge1.macsandbox);
sandbox_if_up(&cfg.bridge1);
if (mac_not_zero(cfg.bridge2.macsandbox))
net_config_mac(cfg.bridge2.devsandbox, cfg.bridge2.macsandbox);
sandbox_if_up(&cfg.bridge2);
if (mac_not_zero(cfg.bridge3.macsandbox))
net_config_mac(cfg.bridge3.devsandbox, cfg.bridge3.macsandbox);
sandbox_if_up(&cfg.bridge3);
// moving an interface in a namespace using --interface will reset the interface configuration;
// we need to put the configuration back
if (cfg.interface0.configured && cfg.interface0.ip) {
if (arg_debug)
printf("Configuring %d.%d.%d.%d address on interface %s\n", PRINT_IP(cfg.interface0.ip), cfg.interface0.dev);
net_config_interface(cfg.interface0.dev, cfg.interface0.ip, cfg.interface0.mask, cfg.interface0.mtu);
}
if (cfg.interface1.configured && cfg.interface1.ip) {
if (arg_debug)
printf("Configuring %d.%d.%d.%d address on interface %s\n", PRINT_IP(cfg.interface1.ip), cfg.interface1.dev);
net_config_interface(cfg.interface1.dev, cfg.interface1.ip, cfg.interface1.mask, cfg.interface1.mtu);
}
if (cfg.interface2.configured && cfg.interface2.ip) {
if (arg_debug)
printf("Configuring %d.%d.%d.%d address on interface %s\n", PRINT_IP(cfg.interface2.ip), cfg.interface2.dev);
net_config_interface(cfg.interface2.dev, cfg.interface2.ip, cfg.interface2.mask, cfg.interface2.mtu);
}
if (cfg.interface3.configured && cfg.interface3.ip) {
if (arg_debug)
printf("Configuring %d.%d.%d.%d address on interface %s\n", PRINT_IP(cfg.interface3.ip), cfg.interface3.dev);
net_config_interface(cfg.interface3.dev, cfg.interface3.ip, cfg.interface3.mask, cfg.interface3.mtu);
}
// add a default route
if (cfg.defaultgw) {
// set the default route
if (net_add_route(0, 0, cfg.defaultgw)) {
fwarning("cannot configure default route\n");
gw_cfg_failed = 1;
}
}
if (arg_debug)
printf("Network namespace enabled\n");
}
// print network configuration
if (!arg_quiet) {
if (any_bridge_configured() || any_interface_configured() || cfg.defaultgw || cfg.dns1) {
fmessage("\n");
if (any_bridge_configured() || any_interface_configured()) {
if (arg_scan)
sbox_run(SBOX_ROOT | SBOX_CAPS_NETWORK | SBOX_SECCOMP, 3, PATH_FNET, "printif", "scan");
else
sbox_run(SBOX_ROOT | SBOX_CAPS_NETWORK | SBOX_SECCOMP, 2, PATH_FNET, "printif");
}
if (cfg.defaultgw != 0) {
if (gw_cfg_failed)
fmessage("Default gateway configuration failed\n");
else
fmessage("Default gateway %d.%d.%d.%d\n", PRINT_IP(cfg.defaultgw));
}
if (cfg.dns1 != NULL)
fmessage("DNS server %s\n", cfg.dns1);
if (cfg.dns2 != NULL)
fmessage("DNS server %s\n", cfg.dns2);
if (cfg.dns3 != NULL)
fmessage("DNS server %s\n", cfg.dns3);
if (cfg.dns4 != NULL)
fmessage("DNS server %s\n", cfg.dns4);
fmessage("\n");
}
}
// load IBUS env variables
if (arg_nonetwork || any_bridge_configured() || any_interface_configured()) {
// do nothing - there are problems with ibus version 1.5.11
}
else {
EUID_USER();
env_ibus_load();
EUID_ROOT();
}
//****************************
// fs pre-processing:
// - build seccomp filters
// - create an empty /etc/ld.so.preload
//****************************
if (cfg.protocol) {
if (arg_debug)
printf("Build protocol filter: %s\n", cfg.protocol);
// build the seccomp filter as a regular user
int rv = sbox_run(SBOX_USER | SBOX_CAPS_NONE | SBOX_SECCOMP, 5,
PATH_FSECCOMP, "protocol", "build", cfg.protocol, RUN_SECCOMP_PROTOCOL);
if (rv)
exit(rv);
}
#ifdef HAVE_FORCE_NONEWPRIVS
bool always_enforce_filters = true;
#else
bool always_enforce_filters = false;
#endif
// need ld.so.preload if tracing or seccomp with any non-default lists
bool need_preload = arg_trace || arg_tracelog || arg_seccomp_postexec;
// for --appimage, --chroot and --overlay* we force NO_NEW_PRIVS
// and drop all capabilities
if (getuid() != 0 && (arg_appimage || cfg.chrootdir || arg_overlay || always_enforce_filters)) {
enforce_filters();
need_preload = arg_trace || arg_tracelog;
}
// trace pre-install
if (need_preload)
fs_trace_preload();
// store hosts file
if (cfg.hosts_file)
fs_store_hosts_file();
//****************************
// configure filesystem
//****************************
#ifdef HAVE_CHROOT
if (cfg.chrootdir) {
fs_chroot(cfg.chrootdir);
//****************************
// trace pre-install, this time inside chroot
//****************************
if (need_preload)
fs_trace_preload();
}
else
#endif
#ifdef HAVE_OVERLAYFS
if (arg_overlay)
fs_overlayfs();
else
#endif
fs_basic_fs();
//****************************
// private mode
//****************************
if (arg_private) {
if (cfg.home_private) { // --private=
if (cfg.chrootdir)
fwarning("private=directory feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private=directory feature is disabled in overlay\n");
else
fs_private_homedir();
}
else if (cfg.home_private_keep) { // --private-home=
if (cfg.chrootdir)
fwarning("private-home= feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private-home= feature is disabled in overlay\n");
else
fs_private_home_list();
}
else // --private
fs_private();
}
if (arg_private_dev)
fs_private_dev();
if (arg_private_opt) {
if (cfg.chrootdir)
fwarning("private-opt feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private-opt feature is disabled in overlay\n");
else {
fs_private_dir_list("/opt", RUN_OPT_DIR, cfg.opt_private_keep);
}
}
if (arg_private_srv) {
if (cfg.chrootdir)
fwarning("private-srv feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private-srv feature is disabled in overlay\n");
else {
fs_private_dir_list("/srv", RUN_SRV_DIR, cfg.srv_private_keep);
}
}
// private-bin is disabled for appimages
if (arg_private_bin && !arg_appimage) {
if (cfg.chrootdir)
fwarning("private-bin feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private-bin feature is disabled in overlay\n");
else {
// for --x11=xorg we need to add xauth command
if (arg_x11_xorg) {
EUID_USER();
char *tmp;
if (asprintf(&tmp, "%s,xauth", cfg.bin_private_keep) == -1)
errExit("asprintf");
cfg.bin_private_keep = tmp;
EUID_ROOT();
}
fs_private_bin_list();
}
}
// private-lib is disabled for appimages
if (arg_private_lib && !arg_appimage) {
if (cfg.chrootdir)
fwarning("private-lib feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private-lib feature is disabled in overlay\n");
else {
fs_private_lib();
}
}
#ifdef HAVE_USERTMPFS
if (arg_private_cache) {
EUID_USER();
profile_add("tmpfs ${HOME}/.cache");
EUID_ROOT();
}
#endif
if (arg_private_tmp) {
// private-tmp is implemented as a whitelist
EUID_USER();
fs_private_tmp();
EUID_ROOT();
}
//****************************
// Session D-BUS
//****************************
#ifdef HAVE_DBUSPROXY
dbus_apply_policy();
#endif
//****************************
// hosts and hostname
//****************************
if (cfg.hostname)
fs_hostname(cfg.hostname);
if (cfg.hosts_file)
fs_mount_hosts_file();
//****************************
// /etc overrides from the network namespace
//****************************
if (arg_netns)
netns_mounts(arg_netns);
//****************************
// update /proc, /sys, /dev, /boot directory
//****************************
fs_proc_sys_dev_boot();
//****************************
// handle /mnt and /media
//****************************
if (checkcfg(CFG_DISABLE_MNT))
fs_mnt(1);
else if (arg_disable_mnt)
fs_mnt(0);
// Install new /etc last, so we can use it as long as possible
if (arg_private_etc) {
if (cfg.chrootdir)
fwarning("private-etc feature is disabled in chroot\n");
else if (arg_overlay)
fwarning("private-etc feature is disabled in overlay\n");
else {
/* Current /etc/passwd and /etc/group files are bind
* mounted filtered versions of originals. Leaving
* them underneath private-etc mount causes problems
* in devices with older kernels, e.g. attempts to
* update the real /etc/passwd file yield EBUSY.
*
* As we do want to retain filtered /etc content:
* 1. duplicate /etc content to RUN_ETC_DIR
* 2. unmount bind mounts from /etc
* 3. mount RUN_ETC_DIR at /etc
*/
fs_private_dir_copy("/etc", RUN_ETC_DIR, cfg.etc_private_keep);
fs_private_dir_copy("/usr/etc", RUN_USR_ETC_DIR, cfg.etc_private_keep); // openSUSE
if (umount2("/etc/group", MNT_DETACH) == -1)
fprintf(stderr, "/etc/group: unmount: %m\n");
if (umount2("/etc/passwd", MNT_DETACH) == -1)
fprintf(stderr, "/etc/passwd: unmount: %m\n");
fs_private_dir_mount("/etc", RUN_ETC_DIR);
fs_private_dir_mount("/usr/etc", RUN_USR_ETC_DIR);
// create /etc/ld.so.preload file again