/* 
   Unix SMB/CIFS implementation.
   Generic authentication types
   Copyright (C) Andrew Bartlett         2001-2002
   Copyright (C) Jelmer Vernooij              2002

   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "auth.h"
#include "lib/util/string_wrappers.h"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_AUTH

/**
 * Return a guest logon for anonymous users (username = "")
 *
 * Typically used as the first module in the auth chain, this allows
 * guest logons to be dealt with in one place.  Non-guest logons 'fail'
 * and pass onto the next module.
 **/

static NTSTATUS check_anonymous_security(const struct auth_context *auth_context,
				void *my_private_data,
				TALLOC_CTX *mem_ctx,
				const struct auth_usersupplied_info *user_info,
				struct auth_serversupplied_info **server_info)
{
	DEBUG(10, ("Check auth for: [%s]\n", user_info->mapped.account_name));

	if (user_info->mapped.account_name && *user_info->mapped.account_name) {
		/* mark this as 'not for me' */
		return NT_STATUS_NOT_IMPLEMENTED;
	}

	switch (user_info->password_state) {
	case AUTH_PASSWORD_PLAIN:
		if (user_info->password.plaintext != NULL &&
		    strlen(user_info->password.plaintext) > 0)
		{
			/* mark this as 'not for me' */
			return NT_STATUS_NOT_IMPLEMENTED;
		}
		break;
	case AUTH_PASSWORD_HASH:
		if (user_info->password.hash.lanman != NULL) {
			/* mark this as 'not for me' */
			return NT_STATUS_NOT_IMPLEMENTED;
		}
		if (user_info->password.hash.nt != NULL) {
			/* mark this as 'not for me' */
			return NT_STATUS_NOT_IMPLEMENTED;
		}
		break;
	case AUTH_PASSWORD_RESPONSE:
		if (user_info->password.response.lanman.length == 1) {
			if (user_info->password.response.lanman.data[0] != '\0') {
				/* mark this as 'not for me' */
				return NT_STATUS_NOT_IMPLEMENTED;
			}
		} else if (user_info->password.response.lanman.length > 1) {
			/* mark this as 'not for me' */
			return NT_STATUS_NOT_IMPLEMENTED;
		}
		if (user_info->password.response.nt.length > 0) {
			/* mark this as 'not for me' */
			return NT_STATUS_NOT_IMPLEMENTED;
		}
		break;
	}

	return make_server_info_anonymous(NULL, server_info);
}

/* Guest modules initialisation */

static NTSTATUS auth_init_anonymous(
	struct auth_context *auth_context,
	const char *options,
	struct auth_methods **auth_method)
{
	struct auth_methods *result;

	result = talloc_zero(auth_context, struct auth_methods);
	if (result == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	result->auth = check_anonymous_security;
	result->name = "anonymous";

        *auth_method = result;
	return NT_STATUS_OK;
}

#ifdef DEVELOPER
/** 
 * Return an error based on username
 *
 * This function allows the testing of obscure errors, as well as the generation
 * of NT_STATUS -> DOS error mapping tables.
 *
 * This module is of no value to end-users.
 *
 * The password is ignored.
 *
 * @return An NTSTATUS value based on the username
 **/

static NTSTATUS check_name_to_ntstatus_security(const struct auth_context *auth_context,
						void *my_private_data, 
						TALLOC_CTX *mem_ctx,
						const struct auth_usersupplied_info *user_info,
						struct auth_serversupplied_info **server_info)
{
	NTSTATUS nt_status;
	fstring user;
	long error_num;

	DEBUG(10, ("Check auth for: [%s]\n", user_info->mapped.account_name));

	fstrcpy(user, user_info->client.account_name);

	if (strnequal("NT_STATUS", user, strlen("NT_STATUS"))) {
		if (!strupper_m(user)) {
			return NT_STATUS_INVALID_PARAMETER;
		}
		return nt_status_string_to_code(user);
	}

	if (!strlower_m(user)) {
		return NT_STATUS_INVALID_PARAMETER;
	}
	error_num = strtoul(user, NULL, 16);

	DEBUG(5,("check_name_to_ntstatus_security: Error for user %s was %lx\n", user, error_num));

	nt_status = NT_STATUS(error_num);

	return nt_status;
}

/** Module initialisation function */

static NTSTATUS auth_init_name_to_ntstatus(
	struct auth_context *auth_context,
	const char *param,
	struct auth_methods **auth_method)
{
	struct auth_methods *result;

	result = talloc_zero(auth_context, struct auth_methods);
	if (result == NULL) {
		return NT_STATUS_NO_MEMORY;
	}
	result->auth = check_name_to_ntstatus_security;
	result->name = "name_to_ntstatus";

        *auth_method = result;
	return NT_STATUS_OK;
}

#endif /* DEVELOPER */

NTSTATUS auth_builtin_init(TALLOC_CTX *mem_ctx)
{
	smb_register_auth(AUTH_INTERFACE_VERSION, "anonymous", auth_init_anonymous);
#ifdef DEVELOPER
	smb_register_auth(AUTH_INTERFACE_VERSION, "name_to_ntstatus", auth_init_name_to_ntstatus);
#endif
	return NT_STATUS_OK;
}