/* ====================================================================
 * Copyright (c) 1996-1999 The Apache Group.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer. 
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the Apache Group
 *    for use in the Apache HTTP server project (http://www.apache.org/)."
 *
 * 4. The names "Apache Server" and "Apache Group" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache"
 *    nor may "Apache" appear in their names without prior written
 *    permission of the Apache Group.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the Apache Group
 *    for use in the Apache HTTP server project (http://www.apache.org/)."
 *
 * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE APACHE GROUP OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Group and was originally based
 * on public domain software written at the National Center for
 * Supercomputing Applications, University of Illinois, Urbana-Champaign.
 * For more information on the Apache Group and the Apache HTTP server
 * project, please see <http://www.apache.org/>.
 *
 * Simple password verify, which 'know's about various password
 * types, such as the simple base64 encoded crypt()s, MD5 $ marked
 * FreeBSD style and netscape SHA1's.
 */
#include <string.h>

#include "ap_config.h"
#include "ap_md5.h"
#include "ap_sha1.h"
#include "ap.h"
#if HAVE_CRYPT_H
#include <crypt.h>
#endif

/*
 * Validate a plaintext password against a smashed one.  Use either
 * crypt() (if available), ap_MD5Encode() or ap_SHA1Encode depending 
 * upon the format of the smashed input password.  
 *
 * Return NULL if they match, or an explanatory text string if they don't.
 */

API_EXPORT(char *) ap_validate_password(const char *passwd, const char *hash)
{
    char sample[120];


    /* FreeBSD style MD5 string 
     */
    if (strncmp(hash, AP_MD5PW_ID, AP_MD5PW_IDLEN) == 0) {

	ap_MD5Encode((const unsigned char *)passwd,
		     (const unsigned char *)hash, sample, sizeof(sample));
    }
    /* Netscape / SHA1 ldap style strng  
     */
    else if (strncmp(hash, AP_SHA1PW_ID, AP_SHA1PW_IDLEN) == 0) {

 	ap_sha1_base64(passwd, strlen(passwd), sample);
    }
    else {
	/*
	 * It's not our algorithm, so feed it to crypt() if possible.
	 */
#if defined(WIN32) || defined(TPF)
	/*
	 * On Windows, the only alternative to our MD5 algorithm is plain
	 * text.
	 */
	ap_cpystrn(sample, passwd, sizeof(sample) - 1);
#else
	ap_cpystrn(sample, (char *)crypt(passwd, hash), sizeof(sample) - 1);
#endif
    }
    return (strcmp(sample, hash) == 0) ? NULL : "password mismatch";
}