/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
 */

#ifndef _KERNEL
#include <stdlib.h>
#include <string.h>
#else
#include <sys/types.h>
#include <sys/sunddi.h>
#endif
#include <smbsrv/string.h>
#include <smbsrv/smb.h>

/*
 * Maximum recursion depth for the wildcard match functions.
 * These functions may recurse when processing a '*'.
 */
#define	SMB_MATCH_DEPTH_MAX	32

#define	SMB_CRC_POLYNOMIAL	0xD8B5D8B5

static int smb_match_private(const char *, const char *, int *);
static int smb_match_ci_private(const char *, const char *, int *);

/*
 * smb_match
 */
boolean_t
smb_match(char *patn, char *str)
{
	int depth = 0;

	return (smb_match_private(patn, str, &depth) == 1);
}

/*
 * The '*' character matches multiple characters.
 * The '?' character matches a single character.
 *
 * If the pattern has trailing '?'s then it matches the specified number
 * of characters or less.  For example, "x??" matches "xab", "xa" and "x",
 * but not "xabc".
 *
 * Returns:
 * 1	match
 * 0	no-match
 * -1	no-match, too many wildcards in pattern
 */
static int
smb_match_private(const char *patn, const char *str, int *depth)
{
	int rc;

	for (;;) {
		switch (*patn) {
		case '\0':
			return (*str == '\0');

		case '?':
			if (*str != 0) {
				str++;
				patn++;
				continue;
			} else {
				return (0);
			}
			/*NOTREACHED*/

		case '*':
			patn += strspn(patn, "*");
			if (*patn == '\0')
				return (1);

			if ((*depth)++ >= SMB_MATCH_DEPTH_MAX)
				return (-1);

			while (*str) {
				rc = smb_match_private(patn, str, depth);
				if (rc != 0)
					return (rc);
				str++;
			}
			return (0);

		default:
			if (*str != *patn)
				return (0);
			str++;
			patn++;
			continue;
		}
	}
	/*NOTREACHED*/
}

/*
 * smb_match_ci
 */
boolean_t
smb_match_ci(char *patn, char *str)
{
	int depth = 0;

	return (smb_match_ci_private(patn, str, &depth) == 1);
}

/*
 * The '*' character matches multiple characters.
 * The '?' character matches a single character.
 *
 * If the pattern has trailing '?'s then it matches the specified number
 * of characters or less.  For example, "x??" matches "xab", "xa" and "x",
 * but not "xabc".
 *
 * Returns:
 * 1	match
 * 0	no-match
 * -1	no-match, too many wildcards in pattern
 */
static int
smb_match_ci_private(const char *patn, const char *str, int *depth)
{
	const char	*p;
	smb_wchar_t	wc1, wc2;
	int		nbytes1, nbytes2;
	int		rc;

	/*
	 * "<" is a special pattern that matches only those names that do
	 * NOT have an extension. "." and ".." are ok.
	 */
	if (strcmp(patn, "<") == 0) {
		if ((strcmp(str, ".") == 0) || (strcmp(str, "..") == 0))
			return (1);
		if (strchr(str, '.') == 0)
			return (1);
		return (0);
	}

	for (;;) {
		switch (*patn) {
		case '\0':
			return (*str == '\0');

		case '?':
			if (*str != 0) {
				str++;
				patn++;
				continue;
			} else {
				p = patn;
				p += strspn(p, "?");
				return ((*p == '\0') ? 1 : 0);
			}
			/*NOTREACHED*/

		case '*':
			patn += strspn(patn, "*");
			if (*patn == '\0')
				return (1);

			if ((*depth)++ >= SMB_MATCH_DEPTH_MAX)
				return (-1);

			while (*str) {
				rc = smb_match_ci_private(patn, str, depth);
				if (rc != 0)
					return (rc);
				str++;
			}
			return (0);

		default:
			nbytes1 = smb_mbtowc(&wc1, patn, MTS_MB_CHAR_MAX);
			nbytes2 = smb_mbtowc(&wc2, str, MTS_MB_CHAR_MAX);
			if ((nbytes1 == -1) || (nbytes2 == -1))
				return (-1);

			if (wc1 != wc2) {
				wc1 = smb_tolower(wc1);
				wc2 = smb_tolower(wc2);
				if (wc1 != wc2)
					return (0);
			}

			patn += nbytes1;
			str += nbytes2;
			continue;
		}
	}
	/*NOTREACHED*/
}

uint32_t
smb_crc_gen(uint8_t *buf, size_t len)
{
	uint32_t crc = SMB_CRC_POLYNOMIAL;
	uint8_t *p;
	int i;

	for (p = buf, i = 0; i < len; ++i, ++p) {
		crc = (crc ^ (uint32_t)*p) + (crc << 12);

		if (crc == 0 || crc == 0xFFFFFFFF)
			crc = SMB_CRC_POLYNOMIAL;
	}

	return (crc);
}