Ejemplo n.º 1
0
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();
	}
	
	
	//****************************
	// 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 etc.
	//****************************
	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);
	}

	// 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
		env_ibus_load();
	
	// grab a copy of cp command
	fs_build_cp_command();
	
	// trace pre-install
	if (arg_trace || arg_tracelog)
		fs_trace_preload();

	//****************************
	// configure filesystem
	//****************************
#ifdef HAVE_SECCOMP
	int enforce_seccomp = 0;
#endif
#ifdef HAVE_CHROOT		
	if (cfg.chrootdir) {
		fs_chroot(cfg.chrootdir);
		// redo cp command
		fs_build_cp_command();
		
		// force caps and seccomp if not started as root
		if (getuid() != 0) {
			// force default seccomp inside the chroot, no keep or drop list
			// the list build on top of the default drop list is kept intact
			arg_seccomp = 1;
#ifdef HAVE_SECCOMP
			enforce_seccomp = 1;
#endif
			if (cfg.seccomp_list_drop) {
				free(cfg.seccomp_list_drop);
				cfg.seccomp_list_drop = NULL;
			}
			if (cfg.seccomp_list_keep) {
				free(cfg.seccomp_list_keep);
				cfg.seccomp_list_keep = NULL;
			}
			
			// disable all capabilities
			if (arg_caps_default_filter || arg_caps_list)
				fprintf(stderr, "Warning: all capabilities disabled for a regular user during chroot\n");
			arg_caps_drop_all = 1;
			
			// drop all supplementary groups; /etc/group file inside chroot
			// is controlled by a regular usr
			arg_nogroups = 1;
			if (!arg_quiet)
				printf("Dropping all Linux capabilities and enforcing default seccomp filter\n");
		}
		else
			arg_seccomp = 1;
						
		//****************************
		// trace pre-install, this time inside chroot
		//****************************
		if (arg_trace || arg_tracelog)
			fs_trace_preload();
	}
	else 
#endif		
	if (arg_overlay)	
		fs_overlayfs();
	else
		fs_basic_fs();
	

	//****************************
	// set hostname in /etc/hostname
	//****************************
	if (cfg.hostname) {
		fs_hostname(cfg.hostname);
	}
	
	//****************************
	// private mode
	//****************************
	if (arg_private) {
		if (cfg.home_private)	// --private=
			fs_private_homedir();
		else // --private
			fs_private();
	}
	
	if (arg_private_dev)
		fs_private_dev();
	if (arg_private_etc) {
		fs_private_etc_list();
		// create /etc/ld.so.preload file again
		if (arg_trace || arg_tracelog)
			fs_trace_preload();
	}
	if (arg_private_bin)
		fs_private_bin_list();
	if (arg_private_tmp)
		fs_private_tmp();
	
	//****************************
	// apply the profile file
	//****************************
	if (cfg.profile) {
		// apply all whitelist commands ... 
		fs_whitelist();
		
		// ... followed by blacklist commands
		fs_blacklist();
	}
	
	//****************************
	// install trace
	//****************************
	if (arg_trace || arg_tracelog)
		fs_trace();
		
	//****************************
	// update /proc, /dev, /boot directorymy
	//****************************
	fs_proc_sys_dev_boot();
	
	//****************************
	// --nosound and fix for pulseaudio 7.0
	//****************************
	if (arg_nosound)
		pulseaudio_disable();
	else
		pulseaudio_init();
	
	//****************************
	// networking
	//****************************
	if (arg_nonetwork) {
		net_if_up("lo");
		if (arg_debug)
			printf("Network namespace enabled, only loopback interface available\n");
	}
	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);
		
		// add a default route
		if (cfg.defaultgw) {
			// set the default route
			if (net_add_route(0, 0, cfg.defaultgw))
				fprintf(stderr, "Warning: cannot configure default route\n");
		}
		
		// enable interfaces
		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_if_ip(cfg.interface0.dev, cfg.interface0.ip, cfg.interface0.mask, cfg.interface0.mtu);
			net_if_up(cfg.interface0.dev);
		}			
		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_if_ip(cfg.interface1.dev, cfg.interface1.ip, cfg.interface1.mask, cfg.interface1.mtu);
			net_if_up(cfg.interface1.dev);
		}			
		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_if_ip(cfg.interface2.dev, cfg.interface2.ip, cfg.interface2.mask, cfg.interface2.mtu);
			net_if_up(cfg.interface2.dev);
		}			
		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_if_ip(cfg.interface3.dev, cfg.interface3.ip, cfg.interface3.mask, cfg.interface3.mtu);
			net_if_up(cfg.interface3.dev);
		}			
			
		if (arg_debug)
			printf("Network namespace enabled\n");
	}
	
	// if any dns server is configured, it is time to set it now
	fs_resolvconf();
	fs_logger_print();
	fs_logger_change_owner();

	// print network configuration
	if (!arg_quiet) {
		if (any_bridge_configured() || any_interface_configured() || cfg.defaultgw || cfg.dns1) {
			printf("\n");
			if (any_bridge_configured() || any_interface_configured())
				net_ifprint();
			if (cfg.defaultgw != 0)
				printf("Default gateway %d.%d.%d.%d\n", PRINT_IP(cfg.defaultgw));
			if (cfg.dns1 != 0)
				printf("DNS server %d.%d.%d.%d\n", PRINT_IP(cfg.dns1));
			if (cfg.dns2 != 0)
				printf("DNS server %d.%d.%d.%d\n", PRINT_IP(cfg.dns2));
			if (cfg.dns3 != 0)
				printf("DNS server %d.%d.%d.%d\n", PRINT_IP(cfg.dns3));
			printf("\n");
		}
	}
	
	fs_delete_cp_command();

	//****************************
	// set application environment
	//****************************
	prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); // kill the child in case the parent died
	int cwd = 0;
	if (cfg.cwd) {
		if (chdir(cfg.cwd) == 0)
			cwd = 1;
	}
	
	if (!cwd) {
		if (chdir("/") < 0)
			errExit("chdir");
		if (cfg.homedir) {
			struct stat s;
			if (stat(cfg.homedir, &s) == 0) {
				/* coverity[toctou] */
				if (chdir(cfg.homedir) < 0)
					errExit("chdir");
			}
		}
	}
	
	// set environment
	env_defaults();
	
	// set user-supplied environment variables
	env_apply();

	// set nice
	if (arg_nice) {
		errno = 0;
		int rv = nice(cfg.nice);
		(void) rv;
		if (errno) {
			fprintf(stderr, "Warning: cannot set nice value\n");
			errno = 0;
		}
	}
	
	// clean /tmp/.X11-unix sockets
	fs_x11();
	
	//****************************
	// set security filters
	//****************************
	// set capabilities
	if (!arg_noroot)
		set_caps();

	// set rlimits
	set_rlimits();

	// set seccomp
#ifdef HAVE_SECCOMP
	// install protocol filter
	if (cfg.protocol) {
		protocol_filter();	// install filter	
		protocol_filter_save();	// save filter in PROTOCOL_CFG
	}

	// if a keep list is available, disregard the drop list
	if (arg_seccomp == 1) {
		if (cfg.seccomp_list_keep)
			seccomp_filter_keep();
		else if (cfg.seccomp_list_errno)
			seccomp_filter_errno(); 
		else
			seccomp_filter_drop(enforce_seccomp);
	}
#endif

	// set cpu affinity
	if (cfg.cpus) {
		save_cpu(); // save cpu affinity mask to CPU_CFG file
		set_cpu_affinity();
	}
	
	// save cgroup in CGROUP_CFG file
	if (cfg.cgroup)
		save_cgroup();

	//****************************************
	// drop privileges or create a new user namespace
	//****************************************
	save_nogroups();
	if (arg_noroot) {
		int rv = unshare(CLONE_NEWUSER);
		if (rv == -1) {
			fprintf(stderr, "Error: cannot mount a new user namespace\n");
			perror("unshare");
			drop_privs(arg_nogroups);
		}
	}
	else
		drop_privs(arg_nogroups);
 	
	// notify parent that new user namespace has been created so a proper
 	// UID/GID map can be setup
 	notify_other(child_to_parent_fds[1]);
 	close(child_to_parent_fds[1]);
 
 	// wait for parent to finish setting up a proper UID/GID map
 	wait_for_other(parent_to_child_fds[0]);
 	close(parent_to_child_fds[0]);

	// somehow, the new user namespace resets capabilities;
	// we need to do them again
	if (arg_noroot) {
		set_caps();
		if (arg_debug)
			printf("noroot user namespace installed\n");
	}


	//****************************************
	// fork the application and monitor it
	//****************************************
	pid_t app_pid = fork();
	if (app_pid == -1)
		errExit("fork");
		
	if (app_pid == 0) {
		prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); // kill the child in case the parent died
		start_application();	// start app
	}

	monitor_application(app_pid);	// monitor application
	
	return 0;
}
Ejemplo n.º 2
0
// check profile line; if line == 0, this was generated from a command line option
// return 1 if the command is to be added to the linked list of profile commands
// return 0 if the command was already executed inside the function
int profile_check_line(char *ptr, int lineno, const char *fname) {
	EUID_ASSERT();
	
	// check ignore list
	int i;
	for (i = 0; i < MAX_PROFILE_IGNORE; i++) {
		if (cfg.profile_ignore[i] == NULL)
			break;
		
		if (strncmp(ptr, cfg.profile_ignore[i], strlen(cfg.profile_ignore[i])) == 0)
			return 0;	// ignore line
	}
	
	if (strncmp(ptr, "ignore ", 7) == 0) {
		char *str = strdup(ptr + 7);
		if (*str == '\0') {
			fprintf(stderr, "Error: invalid ignore option\n");
			exit(1);
		}
		// find an empty entry in profile_ignore array
		int j;
		for (j = 0; j < MAX_PROFILE_IGNORE; j++) {
			if (cfg.profile_ignore[j] == NULL) 
				break;
		}
		if (j >= MAX_PROFILE_IGNORE) {
			fprintf(stderr, "Error: maximum %d --ignore options are permitted\n", MAX_PROFILE_IGNORE);
			exit(1);
		}
		// ... and configure it
		else 
			cfg.profile_ignore[j] = str;

		return 0;
	}

	// mkdir 
	if (strncmp(ptr, "mkdir ", 6) == 0) {
		fs_mkdir(ptr + 6);
		return 0;
	}
	// sandbox name
	else if (strncmp(ptr, "name ", 5) == 0) {
		cfg.name = ptr + 5;
		if (strlen(cfg.name) == 0) {
			fprintf(stderr, "Error: invalid sandbox name\n");
			exit(1);
		}
		return 0;
	}
	else if (strcmp(ptr, "ipc-namespace") == 0) {
		arg_ipc = 1;
		return 0;
	}
	// seccomp, caps, private, user namespace
	else if (strcmp(ptr, "noroot") == 0) {
#if HAVE_USERNS
		if (checkcfg(CFG_USERNS))
			check_user_namespace();
		else
			fprintf(stderr, "Warning: user namespace feature is disabled in Firejail configuration file\n");
#endif

		return 0;
	}
	else if (strcmp(ptr, "nonewprivs") == 0) {
		arg_nonewprivs = 1;
		return 0;
	}
	else if (strcmp(ptr, "seccomp") == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP))
			arg_seccomp = 1;
		else
			fprintf(stderr, "Warning: user seccomp feature is disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	else if (strcmp(ptr, "caps") == 0) {
		arg_caps_default_filter = 1;
		return 0;
	}
	else if (strcmp(ptr, "caps.drop all") == 0) {
		arg_caps_drop_all = 1;
		return 0;
	}
	else if (strcmp(ptr, "shell none") == 0) {
		arg_shell_none = 1;
		return 0;
	}	
	else if (strcmp(ptr, "tracelog") == 0) {
		arg_tracelog = 1;
		return 0;
	}
	else if (strcmp(ptr, "private") == 0) {
		arg_private = 1;
		return 0;
	}
	else if (strcmp(ptr, "private-dev") == 0) {
		arg_private_dev = 1;
		return 0;
	}
	else if (strcmp(ptr, "private-tmp") == 0) {
		arg_private_tmp = 1;
		return 0;
	}
	else if (strcmp(ptr, "nogroups") == 0) {
		arg_nogroups = 1;
		return 0;
	}
	else if (strcmp(ptr, "nosound") == 0) {
		arg_nosound = 1;
		arg_private_dev = 1;
		return 0;
	}
	else if (strcmp(ptr, "netfilter") == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK))
			arg_netfilter = 1;
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	else if (strncmp(ptr, "netfilter ", 10) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			arg_netfilter = 1;
			arg_netfilter_file = strdup(ptr + 10);
			if (!arg_netfilter_file)
				errExit("strdup");
			check_netfilter_file(arg_netfilter_file);
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	else if (strncmp(ptr, "netfilter6 ", 11) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			arg_netfilter6 = 1;
			arg_netfilter6_file = strdup(ptr + 11);
			if (!arg_netfilter6_file)
				errExit("strdup");
			check_netfilter_file(arg_netfilter6_file);
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	else if (strcmp(ptr, "net none") == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			arg_nonetwork  = 1;
			cfg.bridge0.configured = 0;
			cfg.bridge1.configured = 0;
			cfg.bridge2.configured = 0;
			cfg.bridge3.configured = 0;
			cfg.interface0.configured = 0;
			cfg.interface1.configured = 0;
			cfg.interface2.configured = 0;
			cfg.interface3.configured = 0;
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	else if (strncmp(ptr, "net ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
#ifdef HAVE_NETWORK_RESTRICTED
			// compile time restricted networking
			if (getuid() != 0) {
				fprintf(stderr, "Error: only \"net none\" is allowed to non-root users\n");
				exit(1);
			}
#endif
			// run time restricted networking
			if (checkcfg(CFG_RESTRICTED_NETWORK) && getuid() != 0) {
				fprintf(stderr, "Error: only \"net none\" is allowed to non-root users\n");
				exit(1);
			}
			
			if (strcmp(ptr + 4, "lo") == 0) {
				fprintf(stderr, "Error: cannot attach to lo device\n");
				exit(1);
			}

			Bridge *br;
			if (cfg.bridge0.configured == 0)
				br = &cfg.bridge0;
			else if (cfg.bridge1.configured == 0)
				br = &cfg.bridge1;
			else if (cfg.bridge2.configured == 0)
				br = &cfg.bridge2;
			else if (cfg.bridge3.configured == 0)
				br = &cfg.bridge3;
			else {
				fprintf(stderr, "Error: maximum 4 network devices are allowed\n");
				exit(1);
			}
			net_configure_bridge(br, ptr + 4);
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	
	else if (strncmp(ptr, "iprange ", 8) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			if (br->iprange_start || br->iprange_end) {
				fprintf(stderr, "Error: cannot configure the IP range twice for the same interface\n");
				exit(1);
			}

			// parse option arguments
			char *firstip = ptr + 8;
			char *secondip = firstip;
			while (*secondip != '\0') {
				if (*secondip == ',')
					break;
				secondip++;
			}
			if (*secondip == '\0') {
				fprintf(stderr, "Error: invalid IP range\n");
				exit(1);
			}
			*secondip = '\0';
			secondip++;
			
			// check addresses
			if (atoip(firstip, &br->iprange_start) || atoip(secondip, &br->iprange_end) ||
			    br->iprange_start >= br->iprange_end) {
				fprintf(stderr, "Error: invalid IP range\n");
				exit(1);
			}
			if (in_netrange(br->iprange_start, br->ip, br->mask) || in_netrange(br->iprange_end, br->ip, br->mask)) {
				fprintf(stderr, "Error: IP range addresses not in network range\n");
				exit(1);
			}
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}


// from here
	else if (strncmp(ptr, "mac ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			
			if (mac_not_zero(br->macsandbox)) {
				fprintf(stderr, "Error: cannot configure the MAC address twice for the same interface\n");
				exit(1);
			}

			// read the address
			if (atomac(ptr + 4, br->macsandbox)) {
				fprintf(stderr, "Error: invalid MAC address\n");
				exit(1);
			}
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}

	else if (strncmp(ptr, "mtu ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			
			if (sscanf(ptr + 4, "%d", &br->mtu) != 1 || br->mtu < 576 || br->mtu > 9198) {
				fprintf(stderr, "Error: invalid mtu value\n");
				exit(1);
			}
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}

	else if (strncmp(ptr, "ip ", 3) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			if (br->arg_ip_none || br->ipsandbox) {
				fprintf(stderr, "Error: cannot configure the IP address twice for the same interface\n");
				exit(1);
			}

			// configure this IP address for the last bridge defined
			if (strcmp(ptr + 3, "none") == 0)
				br->arg_ip_none = 1;
			else {
				if (atoip(ptr + 3, &br->ipsandbox)) {
					fprintf(stderr, "Error: invalid IP address\n");
					exit(1);
				}
			}
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}

	else if (strncmp(ptr, "ip6 ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			if (br->arg_ip_none || br->ip6sandbox) {
				fprintf(stderr, "Error: cannot configure the IP address twice for the same interface\n");
				exit(1);
			}

			// configure this IP address for the last bridge defined
			// todo: verify ipv6 syntax
			br->ip6sandbox = ptr + 4;
//			if (atoip(argv[i] + 5, &br->ipsandbox)) {
//				fprintf(stderr, "Error: invalid IP address\n");
//				exit(1);
//			}
			
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}

	else if (strncmp(ptr, "defaultgw ", 10) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			if (atoip(ptr + 10, &cfg.defaultgw)) {
				fprintf(stderr, "Error: invalid IP address\n");
				exit(1);
			}
		}
		else
			fprintf(stderr, "Warning: networking features are disabled in Firejail configuration file\n");
#endif
		return 0;
	}

	if (strncmp(ptr, "protocol ", 9) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP))
			protocol_store(ptr + 9);
		else
			fprintf(stderr, "Warning: user seccomp feature is disabled in Firejail configuration file\n");
#endif
		return 0;
	}
	
	if (strncmp(ptr, "env ", 4) == 0) {
		env_store(ptr + 4);
		return 0;
	}
	
	// seccomp drop list on top of default list
	if (strncmp(ptr, "seccomp ", 8) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			arg_seccomp = 1;
			cfg.seccomp_list = strdup(ptr + 8);
			if (!cfg.seccomp_list)
				errExit("strdup");
		}
		else
			fprintf(stderr, "Warning: user seccomp feature is disabled in Firejail configuration file\n");
#endif

		return 0;
	}
	
	// seccomp drop list without default list
	if (strncmp(ptr, "seccomp.drop ", 13) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			arg_seccomp = 1;
			cfg.seccomp_list_drop = strdup(ptr + 13);
			if (!cfg.seccomp_list_drop)
				errExit("strdup");
		}
		else
			fprintf(stderr, "Warning: user seccomp feature is disabled in Firejail configuration file\n");
#endif		
		return 0;
	}

	// seccomp keep list
	if (strncmp(ptr, "seccomp.keep ", 13) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			arg_seccomp = 1;
			cfg.seccomp_list_keep= strdup(ptr + 13);
			if (!cfg.seccomp_list_keep)
				errExit("strdup");
		}
		else
			fprintf(stderr, "Warning: user seccomp feature is disabled in Firejail configuration file\n");
#endif		
		return 0;
	}
	
	// caps drop list
	if (strncmp(ptr, "caps.drop ", 10) == 0) {
		arg_caps_drop = 1;
		arg_caps_list = strdup(ptr + 10);
		if (!arg_caps_list)
			errExit("strdup");
		// verify seccomp list and exit if problems
		if (caps_check_list(arg_caps_list, NULL))
			exit(1);
		return 0;
	}
	
	// caps keep list
	if (strncmp(ptr, "caps.keep ", 10) == 0) {
		arg_caps_keep = 1;
		arg_caps_list = strdup(ptr + 10);
		if (!arg_caps_list)
			errExit("strdup");
		// verify seccomp list and exit if problems
		if (caps_check_list(arg_caps_list, NULL))
			exit(1);
		return 0;
	}

	// hostname
	if (strncmp(ptr, "hostname ", 9) == 0) {
		cfg.hostname = ptr + 9;
		return 0;
	}
	
	// dns
	if (strncmp(ptr, "dns ", 4) == 0) {
		uint32_t dns;
		if (atoip(ptr + 4, &dns)) {
			fprintf(stderr, "Error: invalid DNS server IP address\n");
			return 1;
		}
		
		if (cfg.dns1 == 0)
			cfg.dns1 = dns;
		else if (cfg.dns2 == 0)
			cfg.dns2 = dns;
		else if (cfg.dns3 == 0)
			cfg.dns3 = dns;
		else {
			fprintf(stderr, "Error: up to 3 DNS servers can be specified\n");
			return 1;
		}
		return 0;
	}
	
	// cpu affinity
	if (strncmp(ptr, "cpu ", 4) == 0) {
		read_cpu_list(ptr + 4);
		return 0;
	}
	
	// nice value
	if (strncmp(ptr, "nice ", 4) == 0) {
		cfg.nice = atoi(ptr + 5);
		if (getuid() != 0 &&cfg.nice < 0)
			cfg.nice = 0;
		arg_nice = 1;
		return 0;
	}

	// cgroup
	if (strncmp(ptr, "cgroup ", 7) == 0) {
		set_cgroup(ptr + 7);
		return 0;
	}
	
	// writable-etc
	if (strcmp(ptr, "writable-etc") == 0) {
		if (cfg.etc_private_keep) {
			fprintf(stderr, "Error: private-etc and writable-etc are mutually exclusive\n");
			exit(1);
		}
		arg_writable_etc = 1;
		return 0;
	}
	
	// writable-var
	if (strcmp(ptr, "writable-var") == 0) {
		arg_writable_var = 1;
		return 0;
	}
	
	// private directory
	if (strncmp(ptr, "private ", 8) == 0) {
		cfg.home_private = ptr + 8;
		fs_check_private_dir();
		arg_private = 1;
		return 0;
	}

	// private /etc list of files and directories
	if (strncmp(ptr, "private-etc ", 12) == 0) {
		if (arg_writable_etc) {
			fprintf(stderr, "Error: --private-etc and --writable-etc are mutually exclusive\n");
			exit(1);
		}
		cfg.etc_private_keep = ptr + 12;
		fs_check_etc_list();
		arg_private_etc = 1;
		
		return 0;
	}

	// private /bin list of files
	if (strncmp(ptr, "private-bin ", 12) == 0) {
		cfg.bin_private_keep = ptr + 12;
		arg_private_bin = 1;
		fs_check_bin_list();
		return 0;
	}

	// filesystem bind
	if (strncmp(ptr, "bind ", 5) == 0) {
#ifdef HAVE_BIND		
		if (checkcfg(CFG_BIND)) {
			if (getuid() != 0) {
				fprintf(stderr, "Error: --bind option is available only if running as root\n");
				exit(1);
			}
	
			// extract two directories
			char *dname1 = ptr + 5;
			char *dname2 = split_comma(dname1); // this inserts a '0 to separate the two dierctories
			if (dname2 == NULL) {
				fprintf(stderr, "Error: missing second directory for bind\n");
				exit(1);
			}
			
			// check directories
			invalid_filename(dname1);
			invalid_filename(dname2);
			if (strstr(dname1, "..") || strstr(dname2, "..")) {
				fprintf(stderr, "Error: invalid file name.\n");
				exit(1);
			}
			if (is_link(dname1) || is_link(dname2)) {
				fprintf(stderr, "Symbolic links are not allowed for bind command\n");
				exit(1);
			}
			
			// insert comma back
			*(dname2 - 1) = ',';
			return 1;
		}
		else {
			fprintf(stderr, "Warning: bind feature is disabled in Firejail configuration file\n");
			return 0;			
		}
#else
		return 0;
#endif		
	}

	// rlimit
	if (strncmp(ptr, "rlimit", 6) == 0) {
		if (strncmp(ptr, "rlimit-nofile ", 14) == 0) {
			ptr += 14;
			if (not_unsigned(ptr)) {
				fprintf(stderr, "Invalid rlimit option on line %d\n", lineno);
				exit(1);
			}
			sscanf(ptr, "%u", &cfg.rlimit_nofile);
			arg_rlimit_nofile = 1;
		}
		else if (strncmp(ptr, "rlimit-nproc ", 13) == 0) {
			ptr += 13;
			if (not_unsigned(ptr)) {
				fprintf(stderr, "Invalid rlimit option on line %d\n", lineno);
				exit(1);
			}
			sscanf(ptr, "%u", &cfg.rlimit_nproc);
			arg_rlimit_nproc = 1;
		}
		else if (strncmp(ptr, "rlimit-fsize ", 13) == 0) {
			ptr += 13;
			if (not_unsigned(ptr)) {
				fprintf(stderr, "Invalid rlimit option on line %d\n", lineno);
				exit(1);
			}
			sscanf(ptr, "%u", &cfg.rlimit_fsize);
			arg_rlimit_fsize = 1;
		}
		else if (strncmp(ptr, "rlimit-sigpending ", 18) == 0) {
			ptr += 18;
			if (not_unsigned(ptr)) {
				fprintf(stderr, "Invalid rlimit option on line %d\n", lineno);
				exit(1);
			}
			sscanf(ptr, "%u", &cfg.rlimit_sigpending);
			arg_rlimit_sigpending = 1;
		}
		else {
			fprintf(stderr, "Invalid rlimit option on line %d\n", lineno);
			exit(1);
		}
		
		return 0;		
	}

	// read-write
	if (strncmp(ptr, "read-write ", 11) == 0) {
		if (getuid() != 0) {
			fprintf(stderr, "Error: read-write command is available only for root user\n");
			exit(1);
		}
		fs_rdwr_add(ptr + 11);
		return 0;
	}

	// rest of filesystem
	if (strncmp(ptr, "blacklist ", 10) == 0)
		ptr += 10;
	else if (strncmp(ptr, "blacklist-nolog ", 16) == 0)
		ptr += 16;
	else if (strncmp(ptr, "noblacklist ", 12) == 0)
		ptr += 12;
	else if (strncmp(ptr, "whitelist ", 10) == 0) {
#ifdef HAVE_WHITELIST		
		if (checkcfg(CFG_WHITELIST)) {
			arg_whitelist = 1;
			ptr += 10;
		}
		else
			return 0;
#else		
		return 0;
#endif
	}
	else if (strncmp(ptr, "read-only ", 10) == 0)
		ptr += 10;
	else if (strncmp(ptr, "tmpfs ", 6) == 0) {
		if (getuid() != 0) {
			fprintf(stderr, "Error: tmpfs available only when running the sandbox as root\n");
			exit(1);
		}
		ptr += 6;
	}
	else {
		if (lineno == 0)
			fprintf(stderr, "Error: \"%s\" as a command line option is invalid\n", ptr);
		else if (fname != NULL)
			fprintf(stderr, "Error: line %d in %s is invalid\n", lineno, fname);
		else
			fprintf(stderr, "Error: line %d in the custom profile is invalid\n", lineno);
		exit(1);
	}

	// some characters just don't belong in filenames
	invalid_filename(ptr);
	if (strstr(ptr, "..")) {
		if (lineno == 0)
			fprintf(stderr, "Error: \"%s\" is an invalid filename\n", ptr);
		else if (fname != NULL)
			fprintf(stderr, "Error: line %d in %s is invalid\n", lineno, fname);
		else
			fprintf(stderr, "Error: line %d in the custom profile is invalid\n", lineno);
		exit(1);
	}
	return 1;
}
Ejemplo n.º 3
0
// check profile line; if line == 0, this was generated from a command line option
// return 1 if the command is to be added to the linked list of profile commands
// return 0 if the command was already executed inside the function
int profile_check_line(char *ptr, int lineno, const char *fname) {
	EUID_ASSERT();

	// check ignore list
	int i;
	for (i = 0; i < MAX_PROFILE_IGNORE; i++) {
		if (cfg.profile_ignore[i] == NULL)
			break;

		if (strncmp(ptr, cfg.profile_ignore[i], strlen(cfg.profile_ignore[i])) == 0)
			return 0;	// ignore line
	}

	if (strncmp(ptr, "ignore ", 7) == 0) {
		char *str = strdup(ptr + 7);
		if (*str == '\0') {
			fprintf(stderr, "Error: invalid ignore option\n");
			exit(1);
		}
		// find an empty entry in profile_ignore array
		int j;
		for (j = 0; j < MAX_PROFILE_IGNORE; j++) {
			if (cfg.profile_ignore[j] == NULL)
				break;
		}
		if (j >= MAX_PROFILE_IGNORE) {
			fprintf(stderr, "Error: maximum %d --ignore options are permitted\n", MAX_PROFILE_IGNORE);
			exit(1);
		}
		// ... and configure it
		else
			cfg.profile_ignore[j] = str;

		return 0;
	}

	// mkdir
	if (strncmp(ptr, "mkdir ", 6) == 0) {
		fs_mkdir(ptr + 6);
		return 1;	// process mkdir again while applying blacklists
	}
	// mkfile
	if (strncmp(ptr, "mkfile ", 7) == 0) {
		fs_mkfile(ptr + 7);
		return 1;	// process mkfile again while applying blacklists
	}
	// sandbox name
	else if (strncmp(ptr, "name ", 5) == 0) {
		cfg.name = ptr + 5;
		if (strlen(cfg.name) == 0) {
			fprintf(stderr, "Error: invalid sandbox name\n");
			exit(1);
		}
		return 0;
	}
	else if (strcmp(ptr, "ipc-namespace") == 0) {
		arg_ipc = 1;
		return 0;
	}
	// seccomp, caps, private, user namespace
	else if (strcmp(ptr, "noroot") == 0) {
#if HAVE_USERNS
		if (checkcfg(CFG_USERNS))
			check_user_namespace();
		else
			warning_feature_disabled("noroot");
#endif

		return 0;
	}
	else if (strcmp(ptr, "nonewprivs") == 0) {
		arg_nonewprivs = 1;
		return 0;
	}
	else if (strcmp(ptr, "seccomp") == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP))
			arg_seccomp = 1;
		else
			warning_feature_disabled("seccomp");
#endif
		return 0;
	}
	else if (strcmp(ptr, "caps") == 0) {
		arg_caps_default_filter = 1;
		return 0;
	}
	else if (strcmp(ptr, "caps.drop all") == 0) {
		arg_caps_drop_all = 1;
		return 0;
	}
	else if (strcmp(ptr, "shell none") == 0) {
		arg_shell_none = 1;
		return 0;
	}
	else if (strcmp(ptr, "tracelog") == 0) {
		arg_tracelog = 1;
		return 0;
	}
	else if (strcmp(ptr, "private") == 0) {
		arg_private = 1;
		return 0;
	}
	if (strncmp(ptr, "private-home ", 13) == 0) {
#ifdef HAVE_PRIVATE_HOME
		if (checkcfg(CFG_PRIVATE_HOME)) {
			if (cfg.home_private_keep) {
				if ( asprintf(&cfg.home_private_keep, "%s,%s", cfg.home_private_keep, ptr + 13) < 0 )
					errExit("asprintf");
			} else
				cfg.home_private_keep = ptr + 13;
			arg_private = 1;
		}
		else
			warning_feature_disabled("private-home");
#endif
		return 0;
	}
	else if (strcmp(ptr, "allusers") == 0) {
		arg_allusers = 1;
		return 0;
	}
	else if (strcmp(ptr, "private-dev") == 0) {
		arg_private_dev = 1;
		return 0;
	}
	else if (strcmp(ptr, "private-tmp") == 0) {
		arg_private_tmp = 1;
		return 0;
	}
	else if (strcmp(ptr, "nogroups") == 0) {
		arg_nogroups = 1;
		return 0;
	}
	else if (strcmp(ptr, "nosound") == 0) {
		arg_nosound = 1;
		return 0;
	}
	else if (strcmp(ptr, "novideo") == 0) {
		arg_novideo = 1;
		return 0;
	}
	else if (strcmp(ptr, "no3d") == 0) {
		arg_no3d = 1;
		return 0;
	}
	else if (strcmp(ptr, "allow-private-blacklist") == 0) {
		arg_allow_private_blacklist = 1;
		return 0;
	}
	else if (strcmp(ptr, "netfilter") == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK))
			arg_netfilter = 1;
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}
	else if (strncmp(ptr, "netfilter ", 10) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			arg_netfilter = 1;
			arg_netfilter_file = strdup(ptr + 10);
			if (!arg_netfilter_file)
				errExit("strdup");
			check_netfilter_file(arg_netfilter_file);
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}
	else if (strncmp(ptr, "netfilter6 ", 11) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			arg_netfilter6 = 1;
			arg_netfilter6_file = strdup(ptr + 11);
			if (!arg_netfilter6_file)
				errExit("strdup");
			check_netfilter_file(arg_netfilter6_file);
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}
	else if (strcmp(ptr, "net none") == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			arg_nonetwork  = 1;
			cfg.bridge0.configured = 0;
			cfg.bridge1.configured = 0;
			cfg.bridge2.configured = 0;
			cfg.bridge3.configured = 0;
			cfg.interface0.configured = 0;
			cfg.interface1.configured = 0;
			cfg.interface2.configured = 0;
			cfg.interface3.configured = 0;
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}
	else if (strncmp(ptr, "net ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
#ifdef HAVE_NETWORK_RESTRICTED
			// compile time restricted networking
			if (getuid() != 0) {
				fprintf(stderr, "Error: only \"net none\" is allowed to non-root users\n");
				exit(1);
			}
#endif
			// run time restricted networking
			if (checkcfg(CFG_RESTRICTED_NETWORK) && getuid() != 0) {
				fprintf(stderr, "Error: only \"net none\" is allowed to non-root users\n");
				exit(1);
			}

			if (strcmp(ptr + 4, "lo") == 0) {
				fprintf(stderr, "Error: cannot attach to lo device\n");
				exit(1);
			}

			Bridge *br;
			if (cfg.bridge0.configured == 0)
				br = &cfg.bridge0;
			else if (cfg.bridge1.configured == 0)
				br = &cfg.bridge1;
			else if (cfg.bridge2.configured == 0)
				br = &cfg.bridge2;
			else if (cfg.bridge3.configured == 0)
				br = &cfg.bridge3;
			else {
				fprintf(stderr, "Error: maximum 4 network devices are allowed\n");
				exit(1);
			}
			net_configure_bridge(br, ptr + 4);
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	else if (strncmp(ptr, "veth-name ", 10) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}

			br->veth_name = strdup(ptr + 10);
			if (br->veth_name == NULL)
				errExit("strdup");
			if (*br->veth_name == '\0') {
				fprintf(stderr, "Error: no veth-name configured\n");
				exit(1);
			}
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	else if (strncmp(ptr, "iprange ", 8) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			if (br->iprange_start || br->iprange_end) {
				fprintf(stderr, "Error: cannot configure the IP range twice for the same interface\n");
				exit(1);
			}

			// parse option arguments
			char *firstip = ptr + 8;
			char *secondip = firstip;
			while (*secondip != '\0') {
				if (*secondip == ',')
					break;
				secondip++;
			}
			if (*secondip == '\0') {
				fprintf(stderr, "Error: invalid IP range\n");
				exit(1);
			}
			*secondip = '\0';
			secondip++;

			// check addresses
			if (atoip(firstip, &br->iprange_start) || atoip(secondip, &br->iprange_end) ||
			    br->iprange_start >= br->iprange_end) {
				fprintf(stderr, "Error: invalid IP range\n");
				exit(1);
			}
			if (in_netrange(br->iprange_start, br->ip, br->mask) || in_netrange(br->iprange_end, br->ip, br->mask)) {
				fprintf(stderr, "Error: IP range addresses not in network range\n");
				exit(1);
			}
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}


	else if (strncmp(ptr, "mac ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}

			if (mac_not_zero(br->macsandbox)) {
				fprintf(stderr, "Error: cannot configure the MAC address twice for the same interface\n");
				exit(1);
			}

			// read the address
			if (atomac(ptr + 4, br->macsandbox)) {
				fprintf(stderr, "Error: invalid MAC address\n");
				exit(1);
			}
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	else if (strncmp(ptr, "mtu ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}

			if (sscanf(ptr + 4, "%d", &br->mtu) != 1 || br->mtu < 576 || br->mtu > 9198) {
				fprintf(stderr, "Error: invalid mtu value\n");
				exit(1);
			}
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	else if (strncmp(ptr, "ip ", 3) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			if (br->arg_ip_none || br->ipsandbox) {
				fprintf(stderr, "Error: cannot configure the IP address twice for the same interface\n");
				exit(1);
			}

			// configure this IP address for the last bridge defined
			if (strcmp(ptr + 3, "none") == 0)
				br->arg_ip_none = 1;
			else {
				if (atoip(ptr + 3, &br->ipsandbox)) {
					fprintf(stderr, "Error: invalid IP address\n");
					exit(1);
				}
			}
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	else if (strncmp(ptr, "ip6 ", 4) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			Bridge *br = last_bridge_configured();
			if (br == NULL) {
				fprintf(stderr, "Error: no network device configured\n");
				exit(1);
			}
			if (br->arg_ip_none || br->ip6sandbox) {
				fprintf(stderr, "Error: cannot configure the IP address twice for the same interface\n");
				exit(1);
			}

			// configure this IP address for the last bridge defined
			// todo: verify ipv6 syntax
			br->ip6sandbox = ptr + 4;
//			if (atoip(argv[i] + 5, &br->ipsandbox)) {
//				fprintf(stderr, "Error: invalid IP address\n");
//				exit(1);
//			}

		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	else if (strncmp(ptr, "defaultgw ", 10) == 0) {
#ifdef HAVE_NETWORK
		if (checkcfg(CFG_NETWORK)) {
			if (atoip(ptr + 10, &cfg.defaultgw)) {
				fprintf(stderr, "Error: invalid IP address\n");
				exit(1);
			}
		}
		else
			warning_feature_disabled("networking");
#endif
		return 0;
	}

	if (strcmp(ptr, "apparmor") == 0) {
#ifdef HAVE_APPARMOR
		arg_apparmor = 1;
#endif
		return 0;
	}

	if (strncmp(ptr, "protocol ", 9) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			if (cfg.protocol) {
				fwarning("a protocol list is present, the new list \"%s\" will not be installed\n", ptr + 9);
				return 0;
			}

			// store list
			cfg.protocol = strdup(ptr + 9);
			if (!cfg.protocol)
				errExit("strdup");
		}
		else
			warning_feature_disabled("seccomp");
#endif
		return 0;
	}

	if (strncmp(ptr, "env ", 4) == 0) {
		env_store(ptr + 4, SETENV);
		return 0;
	}
	if (strncmp(ptr, "rmenv ", 6) == 0) {
		env_store(ptr + 6, RMENV);
		return 0;
	}

	// seccomp drop list on top of default list
	if (strncmp(ptr, "seccomp ", 8) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			arg_seccomp = 1;
			cfg.seccomp_list = seccomp_check_list(ptr + 8);
		}
		else if (!arg_quiet)
			warning_feature_disabled("seccomp");
#endif

		return 0;
	}

	// seccomp drop list without default list
	if (strncmp(ptr, "seccomp.drop ", 13) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			arg_seccomp = 1;
			cfg.seccomp_list_drop = seccomp_check_list(ptr + 13);
		}
		else
			warning_feature_disabled("seccomp");
#endif
		return 0;
	}

	// seccomp keep list
	if (strncmp(ptr, "seccomp.keep ", 13) == 0) {
#ifdef HAVE_SECCOMP
		if (checkcfg(CFG_SECCOMP)) {
			arg_seccomp = 1;
			cfg.seccomp_list_keep= seccomp_check_list(ptr + 13);
		}
		else
			warning_feature_disabled("seccomp");
#endif
		return 0;
	}

	// caps drop list
	if (strncmp(ptr, "caps.drop ", 10) == 0) {
		arg_caps_drop = 1;
		arg_caps_list = strdup(ptr + 10);
		if (!arg_caps_list)
			errExit("strdup");
		// verify caps list and exit if problems
		caps_check_list(arg_caps_list, NULL);
		return 0;
	}

	// caps keep list
	if (strncmp(ptr, "caps.keep ", 10) == 0) {
		arg_caps_keep = 1;
		arg_caps_list = strdup(ptr + 10);
		if (!arg_caps_list)
			errExit("strdup");
		// verify caps list and exit if problems
		caps_check_list(arg_caps_list, NULL);
		return 0;
	}

	// hostname
	if (strncmp(ptr, "hostname ", 9) == 0) {
		cfg.hostname = ptr + 9;
		return 0;
	}

	// hosts-file
	if (strncmp(ptr, "hosts-file ", 11) == 0) {
		cfg.hosts_file = fs_check_hosts_file(ptr + 11);
		return 0;
	}

	// dns
	if (strncmp(ptr, "dns ", 4) == 0) {
		uint32_t dns;
		if (atoip(ptr + 4, &dns)) {
			fprintf(stderr, "Error: invalid DNS server IP address\n");
			return 1;
		}

		if (cfg.dns1 == 0)
			cfg.dns1 = dns;
		else if (cfg.dns2 == 0)
			cfg.dns2 = dns;
		else if (cfg.dns3 == 0)
			cfg.dns3 = dns;
		else {
			fprintf(stderr, "Error: up to 3 DNS servers can be specified\n");
			return 1;
		}
		return 0;
	}

	// cpu affinity
	if (strncmp(ptr, "cpu ", 4) == 0) {
		read_cpu_list(ptr + 4);
		return 0;
	}

	// nice value
	if (strncmp(ptr, "nice ", 4) == 0) {
		cfg.nice = atoi(ptr + 5);
		if (getuid() != 0 &&cfg.nice < 0)
			cfg.nice = 0;
		arg_nice = 1;
		return 0;
	}

	// cgroup
	if (strncmp(ptr, "cgroup ", 7) == 0) {
		set_cgroup(ptr + 7);
		return 0;
	}

	// writable-etc
	if (strcmp(ptr, "writable-etc") == 0) {
		if (cfg.etc_private_keep) {
			fprintf(stderr, "Error: private-etc and writable-etc are mutually exclusive\n");
			exit(1);
		}
		arg_writable_etc = 1;
		return 0;
	}

	if (strcmp(ptr, "machine-id") == 0) {
		arg_machineid = 1;
		return 0;
	}
	// writable-var
	if (strcmp(ptr, "writable-var") == 0) {
		arg_writable_var = 1;
		return 0;
	}
	if (strcmp(ptr, "writable-var-log") == 0) {
		arg_writable_var_log = 1;
		return 0;
	}

	// private directory
	if (strncmp(ptr, "private ", 8) == 0) {
		cfg.home_private = ptr + 8;
		fs_check_private_dir();
		arg_private = 1;
		return 0;
	}

	if (strcmp(ptr, "x11 none") == 0) {
		arg_x11_block = 1;
		return 0;
	}

	if (strcmp(ptr, "x11 xephyr") == 0) {
#ifdef HAVE_X11
		if (checkcfg(CFG_X11)) {
			char *x11env = getenv("FIREJAIL_X11");
			if (x11env && strcmp(x11env, "yes") == 0) {
				return 0;
			}
			else {
				// start x11
				x11_start_xephyr(cfg.original_argc, cfg.original_argv);
				exit(0);
			}
		}
		else
			warning_feature_disabled("x11");
#endif
		return 0;
	}

	if (strcmp(ptr, "x11 xorg") == 0) {
#ifdef HAVE_X11
		if (checkcfg(CFG_X11))
			arg_x11_xorg = 1;
		else
			warning_feature_disabled("x11");
#endif
		return 0;
	}

	if (strcmp(ptr, "x11 xpra") == 0) {
#ifdef HAVE_X11
		if (checkcfg(CFG_X11)) {
			char *x11env = getenv("FIREJAIL_X11");
			if (x11env && strcmp(x11env, "yes") == 0) {
				return 0;
			}
			else {
				// start x11
				x11_start_xpra(cfg.original_argc, cfg.original_argv);
				exit(0);
			}
		}
		else
			warning_feature_disabled("x11");
#endif
		return 0;
	}

	if (strcmp(ptr, "x11 xvfb") == 0) {
#ifdef HAVE_X11
		if (checkcfg(CFG_X11)) {
			char *x11env = getenv("FIREJAIL_X11");
			if (x11env && strcmp(x11env, "yes") == 0) {
				return 0;
			}
			else {
				// start x11
				x11_start_xvfb(cfg.original_argc, cfg.original_argv);
				exit(0);
			}
		}
		else
			warning_feature_disabled("x11");
#endif
		return 0;
	}

	if (strcmp(ptr, "x11") == 0) {
#ifdef HAVE_X11
		if (checkcfg(CFG_X11)) {
			char *x11env = getenv("FIREJAIL_X11");
			if (x11env && strcmp(x11env, "yes") == 0) {
				return 0;
			}
			else {
				// start x11
				x11_start(cfg.original_argc, cfg.original_argv);
				exit(0);
			}
		}
		else
			warning_feature_disabled("x11");
#endif
		return 0;
	}

	// private /etc list of files and directories
	if (strncmp(ptr, "private-etc ", 12) == 0) {
		if (arg_writable_etc) {
			fprintf(stderr, "Error: --private-etc and --writable-etc are mutually exclusive\n");
			exit(1);
		}
		if (cfg.etc_private_keep) {
			if ( asprintf(&cfg.etc_private_keep, "%s,%s", cfg.etc_private_keep, ptr + 12) < 0 )
				errExit("asprintf");
		} else {
			cfg.etc_private_keep = ptr + 12;
		}
		arg_private_etc = 1;

		return 0;
	}

	// private /opt list of files and directories
	if (strncmp(ptr, "private-opt ", 12) == 0) {
		if (cfg.opt_private_keep) {
			if ( asprintf(&cfg.opt_private_keep, "%s,%s", cfg.opt_private_keep, ptr + 12) < 0 )
				errExit("asprintf");
		} else {
			cfg.opt_private_keep = ptr + 12;
		}
		arg_private_opt = 1;

		return 0;
	}

	// private /srv list of files and directories
	if (strncmp(ptr, "private-srv ", 12) == 0) {
		if (cfg.srv_private_keep) {
			if ( asprintf(&cfg.srv_private_keep, "%s,%s", cfg.srv_private_keep, ptr + 12) < 0 )
				errExit("asprintf");
		} else {
			cfg.srv_private_keep = ptr + 12;
		}
		arg_private_srv = 1;

		return 0;
	}

	// private /bin list of files
	if (strncmp(ptr, "private-bin ", 12) == 0) {
		if (cfg.bin_private_keep) {
			if ( asprintf(&cfg.bin_private_keep, "%s,%s", cfg.bin_private_keep, ptr + 12) < 0 )
				errExit("asprintf");
		} else {
			cfg.bin_private_keep = ptr + 12;
		}
		arg_private_bin = 1;
		return 0;
	}


#ifdef HAVE_OVERLAYFS
	if (strncmp(ptr, "overlay-named ", 14) == 0) {
		if (checkcfg(CFG_OVERLAYFS)) {
			if (cfg.chrootdir) {
				fprintf(stderr, "Error: --overlay and --chroot options are mutually exclusive\n");
				exit(1);
			}
			struct stat s;
			if (stat("/proc/sys/kernel/grsecurity", &s) == 0) {
				fprintf(stderr, "Error: --overlay option is not available on Grsecurity systems\n");
				exit(1);
			}
			arg_overlay = 1;
			arg_overlay_keep = 1;
			arg_overlay_reuse = 1;

			char *subdirname = ptr + 14;
			if (subdirname == '\0') {
				fprintf(stderr, "Error: invalid overlay option\n");
				exit(1);
			}

			// check name
			invalid_filename(subdirname);
			if (strstr(subdirname, "..") || strstr(subdirname, "/")) {
				fprintf(stderr, "Error: invalid overlay name\n");
				exit(1);
			}
			cfg.overlay_dir = fs_check_overlay_dir(subdirname, arg_overlay_reuse);
		}

		return 0;
	} else if (strcmp(ptr, "overlay-tmpfs") == 0) {
		if (checkcfg(CFG_OVERLAYFS)) {
			if (cfg.chrootdir) {
				fprintf(stderr, "Error: --overlay and --chroot options are mutually exclusive\n");
				exit(1);
			}
			struct stat s;
			if (stat("/proc/sys/kernel/grsecurity", &s) == 0) {
				fprintf(stderr, "Error: --overlay option is not available on Grsecurity systems\n");
				exit(1);
			}
			arg_overlay = 1;

			return 0;
		}
	} else if (strcmp(ptr, "overlay") == 0) {
		if (checkcfg(CFG_OVERLAYFS)) {
			if (cfg.chrootdir) {
				fprintf(stderr, "Error: --overlay and --chroot options are mutually exclusive\n");
				exit(1);
			}
			struct stat s;
			if (stat("/proc/sys/kernel/grsecurity", &s) == 0) {
				fprintf(stderr, "Error: --overlay option is not available on Grsecurity systems\n");
				exit(1);
			}
			arg_overlay = 1;
			arg_overlay_keep = 1;

			char *subdirname;
			if (asprintf(&subdirname, "%d", getpid()) == -1)
				errExit("asprintf");
			cfg.overlay_dir = fs_check_overlay_dir(subdirname, arg_overlay_reuse);

			free(subdirname);

			return 0;
		}
	}
#endif

	// filesystem bind
	if (strncmp(ptr, "bind ", 5) == 0) {
#ifdef HAVE_BIND
		if (checkcfg(CFG_BIND)) {
			if (getuid() != 0) {
				fprintf(stderr, "Error: --bind option is available only if running as root\n");
				exit(1);
			}

			// extract two directories
			char *dname1 = ptr + 5;
			char *dname2 = split_comma(dname1); // this inserts a '0 to separate the two dierctories
			if (dname2 == NULL) {
				fprintf(stderr, "Error: missing second directory for bind\n");
				exit(1);
			}

			// check directories
			invalid_filename(dname1);
			invalid_filename(dname2);
			if (strstr(dname1, "..") || strstr(dname2, "..")) {
				fprintf(stderr, "Error: invalid file name.\n");
				exit(1);
			}
			if (is_link(dname1) || is_link(dname2)) {
				fprintf(stderr, "Symbolic links are not allowed for bind command\n");
				exit(1);
			}

			// insert comma back
			*(dname2 - 1) = ',';
			return 1;
		}
		else
			warning_feature_disabled("bind");
#endif
		return 0;
	}

	// rlimit
	if (strncmp(ptr, "rlimit", 6) == 0) {
		if (strncmp(ptr, "rlimit-nofile ", 14) == 0) {
			check_unsigned(ptr + 14, "Error: invalid rlimit in profile file: ");
			sscanf(ptr + 14, "%llu", &cfg.rlimit_nofile);
			arg_rlimit_nofile = 1;
		}
		else if (strncmp(ptr, "rlimit-nproc ", 13) == 0) {
			check_unsigned(ptr + 13, "Error: invalid rlimit in profile file: ");
			sscanf(ptr + 13, "%llu", &cfg.rlimit_nproc);
			arg_rlimit_nproc = 1;
		}
		else if (strncmp(ptr, "rlimit-fsize ", 13) == 0) {
			check_unsigned(ptr + 13, "Error: invalid rlimit in profile file: ");
			sscanf(ptr + 13, "%llu", &cfg.rlimit_fsize);
			arg_rlimit_fsize = 1;
		}
		else if (strncmp(ptr, "rlimit-sigpending ", 18) == 0) {
			check_unsigned(ptr + 18, "Error: invalid rlimit in profile file: ");
			sscanf(ptr + 18, "%llu", &cfg.rlimit_sigpending);
			arg_rlimit_sigpending = 1;
		}
		else {
			fprintf(stderr, "Invalid rlimit option on line %d\n", lineno);
			exit(1);
		}

		return 0;
	}

	if (strncmp(ptr, "join-or-start ", 14) == 0) {
		// try to join by name only
		pid_t pid;
		if (!name2pid(ptr + 14, &pid)) {
			if (!cfg.shell && !arg_shell_none)
				cfg.shell = guess_shell();

			// find first non-option arg
			int i;
			for (i = 1; i < cfg.original_argc && strncmp(cfg.original_argv[i], "--", 2) != 0; i++);

			join(pid, cfg.original_argc,cfg.original_argv, i + 1);
			exit(0);
		}

		// set sandbox name and start normally
		cfg.name = ptr + 14;
		if (strlen(cfg.name) == 0) {
			fprintf(stderr, "Error: invalid sandbox name\n");
			exit(1);
		}
		return 0;
	}

	// rest of filesystem
	if (strncmp(ptr, "blacklist ", 10) == 0)
		ptr += 10;
	else if (strncmp(ptr, "blacklist-nolog ", 16) == 0)
		ptr += 16;
	else if (strncmp(ptr, "noblacklist ", 12) == 0)
		ptr += 12;
	else if (strncmp(ptr, "whitelist ", 10) == 0) {
#ifdef HAVE_WHITELIST
		if (checkcfg(CFG_WHITELIST)) {
			arg_whitelist = 1;
			ptr += 10;
		}
		else
			return 0;
#else
		return 0;
#endif
	}
	else if (strncmp(ptr, "nowhitelist ", 12) == 0)
		ptr += 12;
	else if (strncmp(ptr, "read-only ", 10) == 0)
		ptr += 10;
	else if (strncmp(ptr, "read-write ", 11) == 0)
		ptr += 11;
	else if (strncmp(ptr, "noexec ", 7) == 0)
		ptr += 7;
	else if (strncmp(ptr, "tmpfs ", 6) == 0) {
		if (getuid() != 0) {
			fprintf(stderr, "Error: tmpfs available only when running the sandbox as root\n");
			exit(1);
		}
		ptr += 6;
	}
	else {
		if (lineno == 0)
			fprintf(stderr, "Error: \"%s\" as a command line option is invalid\n", ptr);
		else if (fname != NULL)
			fprintf(stderr, "Error: line %d in %s is invalid\n", lineno, fname);
		else
			fprintf(stderr, "Error: line %d in the custom profile is invalid\n", lineno);
		exit(1);
	}

	// some characters just don't belong in filenames
	invalid_filename(ptr);
	if (strstr(ptr, "..")) {
		if (lineno == 0)
			fprintf(stderr, "Error: \"%s\" is an invalid filename\n", ptr);
		else if (fname != NULL)
			fprintf(stderr, "Error: line %d in %s is invalid\n", lineno, fname);
		else
			fprintf(stderr, "Error: line %d in the custom profile is invalid\n", lineno);
		exit(1);
	}
	return 1;
}
Ejemplo n.º 4
0
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();
	}
	
	//****************************
	// netfilter
	//****************************
	if (arg_netfilter && any_bridge_configured()) { // assuming by default the client filter
		netfilter(arg_netfilter_file);
	}

	//****************************
	// trace pre-install
	//****************************
	if (arg_trace)
		fs_trace_preload();

	//****************************
	// configure filesystem
	//****************************
	
#ifdef HAVE_CHROOT		
	if (cfg.chrootdir) {
		fs_chroot(cfg.chrootdir);
		// force caps and seccomp if not started as root
		if (getuid() != 0) {
			// force default seccomp inside the chroot, no keep or drop list
			// the list build on top of the default drop list is kept intact
			arg_seccomp = 1;
			if (arg_seccomp_list_drop) {
				free(arg_seccomp_list_drop);
				arg_seccomp_list_drop = NULL;
			}
			if (arg_seccomp_list_keep) {
				free(arg_seccomp_list_keep);
				arg_seccomp_list_keep = NULL;
			}
			
			// disable all capabilities
			if (arg_caps_default_filter || arg_caps_list)
				fprintf(stderr, "Warning: all capabilities disabled for a regular user during chroot\n");
			arg_caps_drop_all = 1;
			
			// drop all supplementary groups; /etc/group file inside chroot
			// is controlled by a regular usr
			arg_nogroups = 1;
			printf("Dropping all Linux capabilities and enforcing default seccomp filter\n");
		}
						
		//****************************
		// trace pre-install, this time inside chroot
		//****************************
		if (arg_trace)
			fs_trace_preload();
	}
	else 
#endif		
	if (arg_overlay)
		fs_overlayfs();
	else
		fs_basic_fs();
	

	//****************************
	// set hostname in /etc/hostname
	//****************************
	if (cfg.hostname) {
		fs_hostname(cfg.hostname);
	}
	
	//****************************
	// apply the profile file
	//****************************
	if (cfg.profile)
		fs_blacklist(cfg.homedir);
	
	//****************************
	// private mode
	//****************************
	if (arg_private) {
		if (cfg.home_private)	// --private=
			fs_private_homedir();
		else if (cfg.home_private_keep) // --private-home=
			fs_private_home_list();
		else // --private
			fs_private();
	}
	
	if (arg_private_dev)
		fs_private_dev();
	if (arg_private_etc)
		fs_private_etc_list();
	
	//****************************
	// install trace
	//****************************
	if (arg_trace)
		fs_trace();
		
	//****************************
	// update /proc, /dev, /boot directorymy
	//****************************
	fs_proc_sys_dev_boot();
	
	//****************************
	// networking
	//****************************
	if (arg_nonetwork) {
		net_if_up("lo");
		if (arg_debug)
			printf("Network namespace enabled, only loopback interface available\n");
	}
	else if (any_bridge_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);
		
		// add a default route
		if (cfg.defaultgw) {
			// set the default route
			if (net_add_route(0, 0, cfg.defaultgw))
				fprintf(stderr, "Warning: cannot configure default route\n");
		}
			
		if (arg_debug)
			printf("Network namespace enabled\n");
	}
	
	// if any dns server is configured, it is time to set it now
	fs_resolvconf();

	// print network configuration
	if (any_bridge_configured() || cfg.defaultgw || cfg.dns1) {
		printf("\n");
		if (any_bridge_configured())
			net_ifprint();
		if (cfg.defaultgw != 0)
			printf("Default gateway %d.%d.%d.%d\n", PRINT_IP(cfg.defaultgw));
		if (cfg.dns1 != 0)
			printf("DNS server %d.%d.%d.%d\n", PRINT_IP(cfg.dns1));
		if (cfg.dns2 != 0)
			printf("DNS server %d.%d.%d.%d\n", PRINT_IP(cfg.dns2));
		if (cfg.dns3 != 0)
			printf("DNS server %d.%d.%d.%d\n", PRINT_IP(cfg.dns3));
		printf("\n");
	}
	
	

	//****************************
	// start executable
	//****************************
	prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); // kill the child in case the parent died
	int cwd = 0;
	if (cfg.cwd) {
		if (chdir(cfg.cwd) == 0)
			cwd = 1;
	}
	
	if (!cwd) {
		if (chdir("/") < 0)
			errExit("chdir");
		if (cfg.homedir) {
			struct stat s;
			if (stat(cfg.homedir, &s) == 0) {
				/* coverity[toctou] */
				if (chdir(cfg.homedir) < 0)
					errExit("chdir");
			}
		}
	}
	
	// set environment
	// fix qt 4.8
	if (setenv("QT_X11_NO_MITSHM", "1", 1) < 0)
		errExit("setenv");
	if (setenv("container", "firejail", 1) < 0) // LXC sets container=lxc,
		errExit("setenv");
	if (arg_zsh && setenv("SHELL", "/usr/bin/zsh", 1) < 0)
		errExit("setenv");
	if (arg_csh && setenv("SHELL", "/bin/csh", 1) < 0)
		errExit("setenv");
	if (cfg.shell && setenv("SHELL", cfg.shell, 1) < 0)
		errExit("setenv");
	// set prompt color to green
	//export PS1='\[\e[1;32m\][\u@\h \W]\$\[\e[0m\] '
	if (setenv("PROMPT_COMMAND", "export PS1=\"\\[\\e[1;32m\\][\\u@\\h \\W]\\$\\[\\e[0m\\] \"", 1) < 0)
		errExit("setenv");
	// set user-supplied environment variables
	env_apply();

	// set capabilities
	if (!arg_noroot)
		set_caps();

	// set rlimits
	set_rlimits();

	// set seccomp
#ifdef HAVE_SECCOMP
	// if a keep list is available, disregard the drop list
	if (arg_seccomp == 1) {
		if (arg_seccomp_list_keep)
			seccomp_filter_keep(); // this will also save the fmyilter to MNT_DIR/seccomp file
		else
			seccomp_filter_drop(); // this will also save the filter to MNT_DIR/seccomp file
	}
#endif

	// set cpu affinity
	if (cfg.cpus) {
		save_cpu(); // save cpu affinity mask to MNT_DIR/cpu file
		set_cpu_affinity();
	}
	
	// save cgroup in MNT_DIR/cgroup file
	if (cfg.cgroup)
		save_cgroup();

	//****************************************
	// drop privileges or create a new user namespace
	//****************************************
	save_nogroups();
	if (arg_noroot) {
		int rv = unshare(CLONE_NEWUSER);
		if (rv == -1) {
			fprintf(stderr, "Error: cannot mount a new user namespace\n");
			perror("unshare");
			drop_privs(arg_nogroups);
		}
	}
	else
		drop_privs(arg_nogroups);
 	
	// notify parent that new user namespace has been created so a proper
 	// UID/GID map can be setup
 	notify_other(child_to_parent_fds[1]);
 	close(child_to_parent_fds[1]);
 
 	// wait for parent to finish setting up a proper UID/GID map
 	wait_for_other(parent_to_child_fds[0]);
 	close(parent_to_child_fds[0]);

	// somehow, the new user namespace resets capabilities;
	// we need to do them again
	if (arg_noroot) {
		set_caps();
		if (arg_debug)
			printf("User namespace (noroot) installed\n");
	}


	//****************************************
	// start the program without using a shell
	//****************************************
	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 (!arg_command)
			printf("Child process initialized\n");
		execvp(cfg.original_argv[cfg.original_program_index], &cfg.original_argv[cfg.original_program_index]);
	}
	//****************************************
	// start the program using a shell
	//****************************************
	else {
		// choose the shell requested by the user, or use bash as default
		char *sh;
		if (cfg.shell)
	 		sh = cfg.shell;
		else if (arg_zsh)
			sh = "/usr/bin/zsh";
		else if (arg_csh)
			sh = "/bin/csh";
		else
			sh = "/bin/bash";
			
		char *arg[5];
		int index = 0;
		arg[index++] = sh;
		arg[index++] = "-c";
		assert(cfg.command_line);
		if (arg_debug)
			printf("Starting %s\n", cfg.command_line);
		if (arg_doubledash) 
			arg[index++] = "--";
		arg[index++] = cfg.command_line;
		arg[index] = NULL;
		assert(index < 5);
		
		if (arg_debug) {
			char *msg;
			if (asprintf(&msg, "sandbox %d, execvp into %s", sandbox_pid, cfg.command_line) == -1)
				errExit("asprintf");
			logmsg(msg);
			free(msg);
		}
		
		if (arg_debug) {
			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)
			printf("Child process initialized\n");
		execvp(sh, arg);
	}
	

	perror("execvp");
	return 0;
}