/* Authors: Karl MacMillan <kmacmillan@tresys.com>
 *          Joshua Brindle <jbrindle@tresys.com>
 *          Jason Tang <jtang@tresys.com>
 *
 * Copyright (C) 2004-2005 Tresys Technology, LLC
 *      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, version 2.
 */

#include <fcntl.h>
#include <getopt.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/types.h>

#include <semanage/modules.h>

enum client_modes { NO_MODE, INSTALL_M, UPGRADE_M, BASE_M, REMOVE_M,
	LIST_M, RELOAD
};
/* list of modes in which one ought to commit afterwards */
static const int do_commit[] = {
	0, 1, 1, 1, 1,
	0, 0
};

struct command {
	enum client_modes mode;
	char *arg;
};
static struct command *commands = NULL;
static int num_commands = 0;

/* options given on command line */
static int verbose;
static int reload;
static int no_reload;
static int create_store;
static int build;

static semanage_handle_t *sh = NULL;
static char *store;

extern char *optarg;
extern int optind;

static void cleanup(void)
{
	while (--num_commands >= 0) {
		free(commands[num_commands].arg);
	}
	free(commands);
}

/* mmap() a file to '*data', returning the total number of bytes in
 * the file.  Returns 0 if file could not be opened or mapped. */
static size_t map_file(char *filename, char **data)
{
	int fd;
	struct stat sb;
	if ((fd = open(filename, O_RDONLY)) == -1) {
		return 0;
	}
	if (fstat(fd, &sb) == -1 ||
	    (*data = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0)) ==
	    MAP_FAILED) {
		sb.st_size = 0;
	}
	close(fd);
	return sb.st_size;
}

/* Signal handlers. */
static void handle_signal(int sig_num)
{
	if (sig_num == SIGINT || sig_num == SIGQUIT || sig_num == SIGTERM) {
		/* catch these signals, and then drop them */
	}
}

static void set_store(char *storename)
{
	/* For now this only supports a store name, later on this 
	 * should support an address for a remote connection */

	if ((store = strdup(storename)) == NULL) {
		fprintf(stderr, "Out of memory!\n");
		goto bad;
	}

	return;

      bad:
	cleanup();
	exit(1);
}

/* Establish signal handlers for the process. */
static void create_signal_handlers(void)
{
	if (signal(SIGINT, handle_signal) == SIG_ERR ||
	    signal(SIGQUIT, handle_signal) == SIG_ERR ||
	    signal(SIGTERM, handle_signal) == SIG_ERR) {
		fprintf(stderr, "Could not set up signal handler.\n");
		exit(255);
	}
}

static void usage(char *progname)
{
	printf("usage:  %s [options]... MODE [MODES]...\n", progname);
	printf("Manage SELinux policy modules.\n");
	printf("MODES:\n");
	printf("  -R, --reload		    reload policy\n");
	printf("  -B, --build		    build and reload policy\n");
	printf("  -i,--install=MODULE_PKG   install a new module\n");
	printf("  -u,--upgrade=MODULE_PKG   upgrade existing module\n");
	printf("  -b,--base=MODULE_PKG      install new base module\n");
	printf("  -r,--remove=MODULE_NAME   remove existing module\n");
	printf
	    ("  -l,--list-modules         display list of installed modules\n");
	printf("Other options:\n");
	printf("  -s,--store	   name of the store to operate on\n");
	printf("  -n,--noreload	   do not reload policy after commit\n");
	printf("  -h,--help        print this message and quit\n");
	printf("  -v,--verbose     be verbose\n");
}

/* Sets the global mode variable to new_mode, but only if no other
 * mode has been given. */
static void set_mode(enum client_modes new_mode, char *arg)
{
	struct command *c;
	char *s;
	if ((c = realloc(commands, sizeof(*c) * (num_commands + 1))) == NULL) {
		fprintf(stderr, "Out of memory!\n");
		cleanup();
		exit(1);
	}
	commands = c;
	commands[num_commands].mode = new_mode;
	commands[num_commands].arg = NULL;
	num_commands++;
	if (arg != NULL) {
		if ((s = strdup(arg)) == NULL) {
			fprintf(stderr, "Out of memory!\n");
			cleanup();
			exit(1);
		}
		commands[num_commands - 1].arg = s;
	}
}

/* Parse command line and set global options. */
static void parse_command_line(int argc, char **argv)
{
	static struct option opts[] = {
		{"store", required_argument, NULL, 's'},
		{"base", required_argument, NULL, 'b'},
		{"help", 0, NULL, 'h'},
		{"install", required_argument, NULL, 'i'},
		{"list-modules", 0, NULL, 'l'},
		{"verbose", 0, NULL, 'v'},
		{"remove", required_argument, NULL, 'r'},
		{"upgrade", required_argument, NULL, 'u'},
		{"reload", 0, NULL, 'R'},
		{"noreload", 0, NULL, 'n'},
		{"build", 0, NULL, 'B'},
		{NULL, 0, NULL, 0}
	};
	int i;
	verbose = 0;
	reload = 0;
	no_reload = 0;
	create_store = 0;
	while ((i =
		getopt_long(argc, argv, "s:b:hi:lvqr:u:RnB", opts,
			    NULL)) != -1) {
		switch (i) {
		case 'b':
			set_mode(BASE_M, optarg);
			create_store = 1;
			break;
		case 'h':
			usage(argv[0]);
			exit(0);
		case 'i':
			set_mode(INSTALL_M, optarg);
			break;
		case 'l':
			set_mode(LIST_M, NULL);
			break;
		case 'v':
			verbose = 1;
			break;
		case 'r':
			set_mode(REMOVE_M, optarg);
			break;
		case 'u':
			set_mode(UPGRADE_M, optarg);
			break;
		case 's':
			set_store(optarg);
			break;
		case 'R':
			reload = 1;
			break;
		case 'n':
			no_reload = 1;
			break;
		case 'B':
			build = 1;
			break;
		case '?':
		default:{
				usage(argv[0]);
				exit(1);
			}
		}
	}
	if (optind < argc) {
		fprintf(stderr, "Extraneous arguments:  ");
		while (optind < argc)
			fprintf(stderr, "%s", argv[optind++]);
		fprintf(stderr, "\n");
		usage(argv[0]);
		cleanup();
		exit(1);
	}
	if ((build || reload) && num_commands) {
		fprintf(stderr,
			"build or reload should not be used with other commands\n");
		usage(argv[0]);
		exit(1);
	}
	if (num_commands == 0 && reload == 0 && build == 0) {
		fprintf(stderr, "At least one mode must be specified.\n");
		usage(argv[0]);
		exit(1);
	}
}

int main(int argc, char *argv[])
{
	int i, commit = 0;
	int result;
	int status = EXIT_FAILURE;

	create_signal_handlers();
	parse_command_line(argc, argv);

	if (build)
		commit = 1;

	sh = semanage_handle_create();
	if (!sh) {
		fprintf(stderr, "%s:  Could not create semanage handle\n",
			argv[0]);
		goto cleanup;
	}

	if (store) {
		/* Set the store we want to connect to, before connecting.
		 * this will always set a direct connection now, an additional
		 * option will need to be used later to specify a policy server 
		 * location */
		semanage_select_store(sh, store, SEMANAGE_CON_DIRECT);
	}

	/* if installing base module create store if necessary, for bootstrapping */
	semanage_set_create_store(sh, create_store);

	if (!create_store) {
		if (!semanage_is_managed(sh)) {
			fprintf(stderr,
				"%s: SELinux policy is not managed or store cannot be accessed.\n",
				argv[0]);
			goto cleanup;
		}

		if (semanage_access_check(sh) < SEMANAGE_CAN_READ) {
			fprintf(stderr, "%s: Cannot read policy store.\n",
				argv[0]);
			goto cleanup;
		}
	}

	if ((result = semanage_connect(sh)) < 0) {
		fprintf(stderr, "%s:  Could not connect to policy handler\n",
			argv[0]);
		goto cleanup;
	}

	if (reload) {
		if ((result = semanage_reload_policy(sh)) < 0) {
			fprintf(stderr, "%s:  Could not reload policy\n",
				argv[0]);
			goto cleanup;
		}
	}

	if (build) {
		if ((result = semanage_begin_transaction(sh)) < 0) {
			fprintf(stderr, "%s:  Could not begin transaction\n",
				argv[0]);
			goto cleanup;
		}
	}

	for (i = 0; i < num_commands; i++) {
		enum client_modes mode = commands[i].mode;
		char *mode_arg = commands[i].arg;
		char *data;
		size_t data_len;
		if (mode == INSTALL_M || mode == UPGRADE_M || mode == BASE_M) {
			if ((data_len = map_file(mode_arg, &data)) == 0) {
				fprintf(stderr,
					"%s:  Could not read file '%s':\n",
					argv[0], mode_arg);
				goto cleanup;
			}
		}
		switch (mode) {
		case INSTALL_M:{
				if (verbose) {
					printf
					    ("Attempting to install module '%s':\n",
					     mode_arg);
				}
				result =
				    semanage_module_install(sh, data, data_len);
				break;
			}
		case UPGRADE_M:{
				if (verbose) {
					printf
					    ("Attempting to upgrade module '%s':\n",
					     mode_arg);
				}
				result =
				    semanage_module_upgrade(sh, data, data_len);
				break;
			}
		case BASE_M:{
				if (verbose) {
					printf
					    ("Attempting to install base module '%s':\n",
					     mode_arg);
				}
				result =
				    semanage_module_install_base(sh, data,
								 data_len);
				break;
			}
		case REMOVE_M:{
				if (verbose) {
					printf
					    ("Attempting to remove module '%s':\n",
					     mode_arg);
				}
				result = semanage_module_remove(sh, mode_arg);
				break;
			}
		case LIST_M:{
				semanage_module_info_t *modinfo;
				int num_modules;
				if (verbose) {
					printf
					    ("Attempting to list active modules:\n");
				}
				if ((result =
				     semanage_module_list(sh, &modinfo,
							  &num_modules)) >= 0) {
					int j;
					if (num_modules == 0) {
						printf("No modules.\n");
					}
					for (j = 0; j < num_modules; j++) {
						semanage_module_info_t *m =
						    semanage_module_list_nth
						    (modinfo, j);
						printf("%s\t%s\n",
						       semanage_module_get_name
						       (m),
						       semanage_module_get_version
						       (m));
						semanage_module_info_datum_destroy
						    (m);
					}
					free(modinfo);
				}
				break;
			}
		default:{
				fprintf(stderr,
					"%s:  Unknown mode specified.\n",
					argv[0]);
				usage(argv[0]);
				goto cleanup;
			}
		}
		commit += do_commit[mode];
		if (mode == INSTALL_M || mode == UPGRADE_M || mode == BASE_M) {
			munmap(data, data_len);
		}
		if (result < 0) {
			fprintf(stderr, "%s:  Failed on %s!\n", argv[0],
				mode_arg ? : "list");
			goto cleanup;
		} else if (verbose) {
			printf("Ok: return value of %d.\n", result);
		}
	}

	if (commit) {
		if (verbose)
			printf("Committing changes:\n");
		if (no_reload)
			semanage_set_reload(sh, 0);
		if (build)
			semanage_set_rebuild(sh, 1);
		result = semanage_commit(sh);
	}

	if (result < 0) {
		fprintf(stderr, "%s:  Failed!\n", argv[0]);
		goto cleanup;
	} else if (commit && verbose) {
		printf("Ok: transaction number %d.\n", result);
	}

	if (semanage_disconnect(sh) < 0) {
		fprintf(stderr, "%s:  Error disconnecting\n", argv[0]);
		goto cleanup;
	}
	status = EXIT_SUCCESS;

      cleanup:
	if (semanage_is_connected(sh)) {
		if (semanage_disconnect(sh) < 0) {
			fprintf(stderr, "%s:  Error disconnecting\n", argv[0]);
		}
	}
	semanage_handle_destroy(sh);
	cleanup();
	exit(status);
}