/**
 *  @file
 *  Implementation of the users without roles module.
 *
 *  @author Kevin Carr kcarr@tresys.com
 *  @author Jeremy A. Mowery jmowery@tresys.com
 *  @author Jason Tang jtang@tresys.com
 *
 *  Copyright (C) 2005-2007 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; 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 St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "users_wo_roles.h"

#include <stdio.h>
#include <string.h>
#include <errno.h>

/* This string is the name of the module and should match the stem
 * of the file name; it should also match the prefix of all functions
 * defined in this module and the private data storage structure */
static const char *const mod_name = "users_wo_roles";

/* The register function registers all of a module's functions
 * with the library. */
int users_wo_roles_register(sechk_lib_t * lib)
{
	sechk_module_t *mod = NULL;
	sechk_fn_t *fn_struct = NULL;

	if (!lib) {
		ERR(NULL, "%s", "No library");
		errno = EINVAL;
		return -1;
	}

	/* Modules are declared by the config file and their name and options
	 * are stored in the module array.  The name is looked up to determine
	 * where to store the function structures */
	mod = sechk_lib_get_module(mod_name, lib);
	if (!mod) {
		ERR(NULL, "%s", "Module unknown");
		errno = EINVAL;
		return -1;
	}
	mod->parent_lib = lib;

	/* assign the descriptions */
	mod->brief_description = "users with no roles";
	mod->detailed_description =
		"--------------------------------------------------------------------------------\n"
		"This module finds all the SELinux users in the policy that have no associated\n"
		"roles.  Users without roles may appear in the label of a file system object;\n"
		"however, these users cannot login to the system or run any process.  Since these\n"
		"users cannot be used on the system, a policy change is recomended to remove the\n"
		"users or provide some intended access.\n";
	mod->opt_description =
		"  Module requirements:\n" "    none\n" "  Module dependencies:\n" "    none\n" "  Module options:\n" "    none\n";
	mod->severity = SECHK_SEV_LOW;
	/* register functions */
	fn_struct = sechk_fn_new();
	if (!fn_struct) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	fn_struct->name = strdup(SECHK_MOD_FN_INIT);
	if (!fn_struct->name) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	fn_struct->fn = users_wo_roles_init;
	if (apol_vector_append(mod->functions, (void *)fn_struct) < 0) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}

	fn_struct = sechk_fn_new();
	if (!fn_struct) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	fn_struct->name = strdup(SECHK_MOD_FN_RUN);
	if (!fn_struct->name) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	fn_struct->fn = users_wo_roles_run;
	if (apol_vector_append(mod->functions, (void *)fn_struct) < 0) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}

	mod->data_free = NULL;

	fn_struct = sechk_fn_new();
	if (!fn_struct) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	fn_struct->name = strdup(SECHK_MOD_FN_PRINT);
	if (!fn_struct->name) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	fn_struct->fn = users_wo_roles_print;
	if (apol_vector_append(mod->functions, (void *)fn_struct) < 0) {
		ERR(NULL, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}

	return 0;
}

/* The init function creates the module's private data storage object
 * and initializes its values based on the options parsed in the config
 * file. */
int users_wo_roles_init(sechk_module_t * mod, apol_policy_t * policy, void *arg __attribute__ ((unused)))
{
	if (!mod || !policy) {
		ERR(policy, "%s", "Invalid parameters");
		errno = EINVAL;
		return -1;
	}
	if (strcmp(mod_name, mod->name)) {
		ERR(policy, "Wrong module (%s)", mod->name);
		errno = EINVAL;
		return -1;
	}

	mod->data = NULL;

	return 0;
}

/* The run function performs the check. This function runs only once
 * even if called multiple times. All test logic should be placed below
 * as instructed. This function allocates the result structure and fills
 * in all relavant item and proof data. */
int users_wo_roles_run(sechk_module_t * mod, apol_policy_t * policy, void *arg __attribute__ ((unused)))
{
	sechk_result_t *res = NULL;
	sechk_item_t *item = NULL;
	sechk_proof_t *proof = NULL;
	size_t i;
	apol_vector_t *user_vector;
	int error = 0;

	if (!mod || !policy) {
		ERR(policy, "%s", "Invalid parameters");
		errno = EINVAL;
		return -1;
	}
	if (strcmp(mod_name, mod->name)) {
		ERR(policy, "Wrong module (%s)", mod->name);
		errno = EINVAL;
		return -1;
	}

	/* if already run return */
	if (mod->result)
		return 0;

	res = sechk_result_new();
	if (!res) {
		ERR(policy, "%s", strerror(ENOMEM));
		errno = ENOMEM;
		return -1;
	}
	res->test_name = strdup(mod_name);
	if (!res->test_name) {
		error = errno;
		ERR(policy, "%s", strerror(ENOMEM));
		goto users_wo_roles_run_fail;
	}
	res->item_type = SECHK_ITEM_USER;
	if (!(res->items = apol_vector_create(sechk_item_free))) {
		error = errno;
		ERR(policy, "%s", strerror(ENOMEM));
		goto users_wo_roles_run_fail;
	}

	apol_user_get_by_query(policy, NULL, &user_vector);
	for (i = 0; i < apol_vector_get_size(user_vector); i++) {
		qpol_user_t *user;
		qpol_iterator_t *role_iter;

		user = apol_vector_get_element(user_vector, i);
		qpol_user_get_role_iter(apol_policy_get_qpol(policy), user, &role_iter);
		if (!qpol_iterator_end(role_iter)) {
			qpol_iterator_destroy(&role_iter);
			continue;
		}
		qpol_iterator_destroy(&role_iter);

		proof = sechk_proof_new(NULL);
		if (!proof) {
			error = errno;
			ERR(policy, "%s", strerror(ENOMEM));
			goto users_wo_roles_run_fail;
		}
		proof->type = SECHK_ITEM_USER;
		proof->text = "User has no roles.\n";
		item = sechk_item_new(NULL);
		if (!item) {
			error = errno;
			ERR(policy, "%s", strerror(ENOMEM));
			goto users_wo_roles_run_fail;
		}
		item->item = (void *)user;
		if (!item->proof) {
			if (!(item->proof = apol_vector_create(sechk_proof_free))) {
				error = errno;
				ERR(policy, "%s", strerror(ENOMEM));
				goto users_wo_roles_run_fail;
			}
		}
		if (apol_vector_append(item->proof, (void *)proof) < 0) {
			error = errno;
			ERR(policy, "%s", strerror(ENOMEM));
			goto users_wo_roles_run_fail;
		}
		if (apol_vector_append(res->items, (void *)item) < 0) {
			error = errno;
			ERR(policy, "%s", strerror(ENOMEM));
			goto users_wo_roles_run_fail;
		}
	}
	apol_vector_destroy(&user_vector);

	mod->result = res;

	if (apol_vector_get_size(res->items))
		return 1;
	return 0;

      users_wo_roles_run_fail:
	sechk_proof_free(proof);
	sechk_item_free(item);
	sechk_result_destroy(&res);
	errno = error;
	return -1;
}

/* The print output function generates the text printed in the
 * report and prints it to stdout. */
int users_wo_roles_print(sechk_module_t * mod, apol_policy_t * policy, void *arg __attribute__ ((unused)))
{
	unsigned char outformat = 0x00;
	sechk_item_t *item = NULL;
	size_t i = 0, j = 0, num_items;
	const qpol_user_t *user;
	const char *user_name;

	if (!mod || !policy) {
		ERR(policy, "%s", "Invalid parameters");
		errno = EINVAL;
		return -1;
	}
	if (strcmp(mod_name, mod->name)) {
		ERR(policy, "Wrong module (%s)", mod->name);
		errno = EINVAL;
		return -1;
	}

	outformat = mod->outputformat;
	num_items = apol_vector_get_size(mod->result->items);

	if (!outformat || (outformat & SECHK_OUT_QUIET))
		return 0;	       /* not an error - no output is requested */

	if (!mod->result) {
		ERR(policy, "%s", "Module has not been run");
		errno = EINVAL;
		return -1;
	}

	/* display the statistics of the results */
	if (outformat & SECHK_OUT_STATS) {
		printf("Found %zd users.\n", num_items);
	}
	if (outformat & SECHK_OUT_PROOF) {
		printf("\nThe following users have no associated roles.\n");
	}
	/* The list report component is a display of all items
	 * found without any supporting proof. */
	if (outformat & (SECHK_OUT_LIST | SECHK_OUT_PROOF)) {
		printf("\n");
		for (i = 0; i < num_items; i++) {
			j++;
			j %= 4;
			item = apol_vector_get_element(mod->result->items, i);
			user = (qpol_user_t *) item->item;
			qpol_user_get_name(apol_policy_get_qpol(policy), user, &user_name);
			printf("%s%s", user_name, (char *)((j && i != num_items - 1) ? ", " : "\n"));
		}
		printf("\n");
	}
	return 0;
}