crypto/apr_md4.c - apr-util - Git at Google

 /* Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance with
  * the License.  You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  *
  * This is derived from material copyright RSA Data Security, Inc.
  * Their notice is reproduced below in its entirety.
  *
  * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
  * rights reserved.
  *
  * License to copy and use this software is granted provided that it
  * is identified as the "RSA Data Security, Inc. MD4 Message-Digest
  * Algorithm" in all material mentioning or referencing this software
  * or this function.
  *
  * License is also granted to make and use derivative works provided
  * that such works are identified as "derived from the RSA Data
  * Security, Inc. MD4 Message-Digest Algorithm" in all material
  * mentioning or referencing the derived work.
  *
  * RSA Data Security, Inc. makes no representations concerning either
  * the merchantability of this software or the suitability of this
  * software for any particular purpose. It is provided "as is"
  * without express or implied warranty of any kind.
  *
  * These notices must be retained in any copies of any part of this
  * documentation and/or software.
  */

 #include "apr_strings.h"
 #include "apr_md4.h"
 #include "apr_lib.h"

 #if APR_HAVE_STRING_H
 #include <string.h>
 #endif
 #if APR_HAVE_UNISTD_H
 #include <unistd.h>
 #endif

 /* Constants for MD4Transform routine.
  */

 #define S11 3
 #define S12 7
 #define S13 11
 #define S14 19
 #define S21 3
 #define S22 5
 #define S23 9
 #define S24 13
 #define S31 3
 #define S32 9
 #define S33 11
 #define S34 15

 static void MD4Transform(apr_uint32_t state[4], const unsigned char block[64]);
 static void Encode(unsigned char *output, const apr_uint32_t *input,
                    unsigned int len);
 static void Decode(apr_uint32_t *output, const unsigned char *input,
                    unsigned int len);

 static unsigned char PADDING[64] =
 {
     0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 };

 #if APR_CHARSET_EBCDIC
 static apr_xlate_t *xlate_ebcdic_to_ascii; /* used in apr_md4_encode() */
 #endif

 /* F, G and I are basic MD4 functions.
  */
 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
 #define H(x, y, z) ((x) ^ (y) ^ (z))

 /* ROTATE_LEFT rotates x left n bits.
  */
 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))

 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
 /* Rotation is separate from addition to prevent recomputation */

 #define FF(a, b, c, d, x, s) { \
   (a) += F ((b), (c), (d)) + (x); \
   (a) = ROTATE_LEFT ((a), (s)); \
   }
 #define GG(a, b, c, d, x, s) { \
   (a) += G ((b), (c), (d)) + (x) + (apr_uint32_t)0x5a827999; \
   (a) = ROTATE_LEFT ((a), (s)); \
   }
 #define HH(a, b, c, d, x, s) { \
   (a) += H ((b), (c), (d)) + (x) + (apr_uint32_t)0x6ed9eba1; \
   (a) = ROTATE_LEFT ((a), (s)); \
   }

 /* MD4 initialization. Begins an MD4 operation, writing a new context.
  */
 APU_DECLARE(apr_status_t) apr_md4_init(apr_md4_ctx_t *context)
 {
     context->count[0] = context->count[1] = 0;

     /* Load magic initialization constants. */
     context->state[0] = 0x67452301;
     context->state[1] = 0xefcdab89;
     context->state[2] = 0x98badcfe;
     context->state[3] = 0x10325476;

 #if APR_HAS_XLATE
     context->xlate = NULL;
 #endif

     return APR_SUCCESS;
 }

 #if APR_HAS_XLATE
 /* MD4 translation setup.  Provides the APR translation handle
  * to be used for translating the content before calculating the
  * digest.
  */
 APU_DECLARE(apr_status_t) apr_md4_set_xlate(apr_md4_ctx_t *context,
                                             apr_xlate_t *xlate)
 {
     apr_status_t rv;
     int is_sb;

     /* TODO: remove the single-byte-only restriction from this code
      */
     rv = apr_xlate_sb_get(xlate, &is_sb);
     if (rv != APR_SUCCESS) {
         return rv;
     }
     if (!is_sb) {
         return APR_EINVAL;
     }
     context->xlate = xlate;
     return APR_SUCCESS;
 }
 #endif /* APR_HAS_XLATE */

 /* MD4 block update operation. Continues an MD4 message-digest
  * operation, processing another message block, and updating the
  * context.
  */
 APU_DECLARE(apr_status_t) apr_md4_update(apr_md4_ctx_t *context,
                                          const unsigned char *input,
                                          apr_size_t inputLen)
 {
     unsigned int i, idx, partLen;
 #if APR_HAS_XLATE
     apr_size_t inbytes_left, outbytes_left;
 #endif

     /* Compute number of bytes mod 64 */
     idx = (unsigned int)((context->count[0] >> 3) & 0x3F);

     /* Update number of bits */
     if ((context->count[0] += ((apr_uint32_t)inputLen << 3))
             < ((apr_uint32_t)inputLen << 3))
         context->count[1]++;
     context->count[1] += (apr_uint32_t)inputLen >> 29;

     partLen = 64 - idx;

     /* Transform as many times as possible. */
 #if !APR_HAS_XLATE
     if (inputLen >= partLen) {
         memcpy(&context->buffer[idx], input, partLen);
         MD4Transform(context->state, context->buffer);

         for (i = partLen; i + 63 < inputLen; i += 64)
             MD4Transform(context->state, &input[i]);

         idx = 0;
     }
     else
         i = 0;

     /* Buffer remaining input */
     memcpy(&context->buffer[idx], &input[i], inputLen - i);
 #else /*APR_HAS_XLATE*/
     if (inputLen >= partLen) {
         if (context->xlate) {
             inbytes_left = outbytes_left = partLen;
             apr_xlate_conv_buffer(context->xlate, (const char *)input,
                                   &inbytes_left,
                                   (char *)&context->buffer[idx],
                                   &outbytes_left);
         }
         else {
             memcpy(&context->buffer[idx], input, partLen);
         }
         MD4Transform(context->state, context->buffer);

         for (i = partLen; i + 63 < inputLen; i += 64) {
             if (context->xlate) {
                 unsigned char inp_tmp[64];
                 inbytes_left = outbytes_left = 64;
                 apr_xlate_conv_buffer(context->xlate, (const char *)&input[i],
                                       &inbytes_left,
                                       (char *)inp_tmp, &outbytes_left);
                 MD4Transform(context->state, inp_tmp);
             }
             else {
                 MD4Transform(context->state, &input[i]);
             }
         }

         idx = 0;
     }
     else
         i = 0;

     /* Buffer remaining input */
     if (context->xlate) {
         inbytes_left = outbytes_left = inputLen - i;
         apr_xlate_conv_buffer(context->xlate, (const char *)&input[i],
                               &inbytes_left, (char *)&context->buffer[idx],
                               &outbytes_left);
     }
     else {
         memcpy(&context->buffer[idx], &input[i], inputLen - i);
     }
 #endif /*APR_HAS_XLATE*/
     return APR_SUCCESS;
 }

 /* MD4 finalization. Ends an MD4 message-digest operation, writing the
  * the message digest and zeroizing the context.
  */
 APU_DECLARE(apr_status_t) apr_md4_final(
                                     unsigned char digest[APR_MD4_DIGESTSIZE],
                                     apr_md4_ctx_t *context)
 {
     unsigned char bits[8];
     unsigned int idx, padLen;

     /* Save number of bits */
     Encode(bits, context->count, 8);

 #if APR_HAS_XLATE
     /* apr_md4_update() should not translate for this final round. */
     context->xlate = NULL;
 #endif /*APR_HAS_XLATE*/

     /* Pad out to 56 mod 64. */
     idx = (unsigned int) ((context->count[0] >> 3) & 0x3f);
     padLen = (idx < 56) ? (56 - idx) : (120 - idx);
     apr_md4_update(context, PADDING, padLen);

     /* Append length (before padding) */
     apr_md4_update(context, bits, 8);

     /* Store state in digest */
     Encode(digest, context->state, APR_MD4_DIGESTSIZE);

     /* Zeroize sensitive information. */
     memset(context, 0, sizeof(*context));

     return APR_SUCCESS;
 }

 /* MD4 computation in one step (init, update, final)
  */
 APU_DECLARE(apr_status_t) apr_md4(unsigned char digest[APR_MD4_DIGESTSIZE],
                                   const unsigned char *input,
                                   apr_size_t inputLen)
 {
     apr_md4_ctx_t ctx;
     apr_status_t rv;

     apr_md4_init(&ctx);

     if ((rv = apr_md4_update(&ctx, input, inputLen)) != APR_SUCCESS)
         return rv;

     return apr_md4_final(digest, &ctx);
 }

 /* MD4 basic transformation. Transforms state based on block. */
 static void MD4Transform(apr_uint32_t state[4], const unsigned char block[64])
 {
     apr_uint32_t a = state[0], b = state[1], c = state[2], d = state[3],
                  x[APR_MD4_DIGESTSIZE];

     Decode(x, block, 64);

     /* Round 1 */
     FF (a, b, c, d, x[ 0], S11); /* 1 */
     FF (d, a, b, c, x[ 1], S12); /* 2 */
     FF (c, d, a, b, x[ 2], S13); /* 3 */
     FF (b, c, d, a, x[ 3], S14); /* 4 */
     FF (a, b, c, d, x[ 4], S11); /* 5 */
     FF (d, a, b, c, x[ 5], S12); /* 6 */
     FF (c, d, a, b, x[ 6], S13); /* 7 */
     FF (b, c, d, a, x[ 7], S14); /* 8 */
     FF (a, b, c, d, x[ 8], S11); /* 9 */
     FF (d, a, b, c, x[ 9], S12); /* 10 */
     FF (c, d, a, b, x[10], S13); /* 11 */
     FF (b, c, d, a, x[11], S14); /* 12 */
     FF (a, b, c, d, x[12], S11); /* 13 */
     FF (d, a, b, c, x[13], S12); /* 14 */
     FF (c, d, a, b, x[14], S13); /* 15 */
     FF (b, c, d, a, x[15], S14); /* 16 */

     /* Round 2 */
     GG (a, b, c, d, x[ 0], S21); /* 17 */
     GG (d, a, b, c, x[ 4], S22); /* 18 */
     GG (c, d, a, b, x[ 8], S23); /* 19 */
     GG (b, c, d, a, x[12], S24); /* 20 */
     GG (a, b, c, d, x[ 1], S21); /* 21 */
     GG (d, a, b, c, x[ 5], S22); /* 22 */
     GG (c, d, a, b, x[ 9], S23); /* 23 */
     GG (b, c, d, a, x[13], S24); /* 24 */
     GG (a, b, c, d, x[ 2], S21); /* 25 */
     GG (d, a, b, c, x[ 6], S22); /* 26 */
     GG (c, d, a, b, x[10], S23); /* 27 */
     GG (b, c, d, a, x[14], S24); /* 28 */
     GG (a, b, c, d, x[ 3], S21); /* 29 */
     GG (d, a, b, c, x[ 7], S22); /* 30 */
     GG (c, d, a, b, x[11], S23); /* 31 */
     GG (b, c, d, a, x[15], S24); /* 32 */

     /* Round 3 */
     HH (a, b, c, d, x[ 0], S31); /* 33 */
     HH (d, a, b, c, x[ 8], S32); /* 34 */
     HH (c, d, a, b, x[ 4], S33); /* 35 */
     HH (b, c, d, a, x[12], S34); /* 36 */
     HH (a, b, c, d, x[ 2], S31); /* 37 */
     HH (d, a, b, c, x[10], S32); /* 38 */
     HH (c, d, a, b, x[ 6], S33); /* 39 */
     HH (b, c, d, a, x[14], S34); /* 40 */
     HH (a, b, c, d, x[ 1], S31); /* 41 */
     HH (d, a, b, c, x[ 9], S32); /* 42 */
     HH (c, d, a, b, x[ 5], S33); /* 43 */
     HH (b, c, d, a, x[13], S34); /* 44 */
     HH (a, b, c, d, x[ 3], S31); /* 45 */
     HH (d, a, b, c, x[11], S32); /* 46 */
     HH (c, d, a, b, x[ 7], S33); /* 47 */
     HH (b, c, d, a, x[15], S34); /* 48 */

     state[0] += a;
     state[1] += b;
     state[2] += c;
     state[3] += d;

     /* Zeroize sensitive information. */
     memset(x, 0, sizeof(x));
 }

 /* Encodes input (apr_uint32_t) into output (unsigned char). Assumes len is
  * a multiple of 4.
  */
 static void Encode(unsigned char *output, const apr_uint32_t *input,
                    unsigned int len)
 {
     unsigned int i, j;
     apr_uint32_t k;

     for (i = 0, j = 0; j < len; i++, j += 4) {
         k = input[i];
         output[j]     = (unsigned char)(k & 0xff);
         output[j + 1] = (unsigned char)((k >> 8)  & 0xff);
         output[j + 2] = (unsigned char)((k >> 16) & 0xff);
         output[j + 3] = (unsigned char)((k >> 24) & 0xff);
     }
 }

 /* Decodes input (unsigned char) into output (apr_uint32_t). Assumes len is
  * a multiple of 4.
  */
 static void Decode(apr_uint32_t *output, const unsigned char *input,
                    unsigned int len)
 {
     unsigned int i, j;

     for (i = 0, j = 0; j < len; i++, j += 4)
         output[i] = ((apr_uint32_t)input[j])             |
                     (((apr_uint32_t)input[j + 1]) << 8)  |
                     (((apr_uint32_t)input[j + 2]) << 16) |
                     (((apr_uint32_t)input[j + 3]) << 24);
 }

 #if APR_CHARSET_EBCDIC
 APU_DECLARE(apr_status_t) apr_MD4InitEBCDIC(apr_xlate_t *xlate)
 {
     xlate_ebcdic_to_ascii = xlate;
     return APR_SUCCESS;
 }
 #endif
	/* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*
	* This is derived from material copyright RSA Data Security, Inc.
	* Their notice is reproduced below in its entirety.
	*
	* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
	* rights reserved.
	*
	* License to copy and use this software is granted provided that it
	* is identified as the "RSA Data Security, Inc. MD4 Message-Digest
	* Algorithm" in all material mentioning or referencing this software
	* or this function.
	*
	* License is also granted to make and use derivative works provided
	* that such works are identified as "derived from the RSA Data
	* Security, Inc. MD4 Message-Digest Algorithm" in all material
	* mentioning or referencing the derived work.
	*
	* RSA Data Security, Inc. makes no representations concerning either
	* the merchantability of this software or the suitability of this
	* software for any particular purpose. It is provided "as is"
	* without express or implied warranty of any kind.
	*
	* These notices must be retained in any copies of any part of this
	* documentation and/or software.
	*/

	#include "apr_strings.h"
	#include "apr_md4.h"
	#include "apr_lib.h"

	#if APR_HAVE_STRING_H
	#include <string.h>
	#endif
	#if APR_HAVE_UNISTD_H
	#include <unistd.h>
	#endif

	/* Constants for MD4Transform routine.
	*/

	#define S11 3
	#define S12 7
	#define S13 11
	#define S14 19
	#define S21 3
	#define S22 5
	#define S23 9
	#define S24 13
	#define S31 3
	#define S32 9
	#define S33 11
	#define S34 15

	static void MD4Transform(apr_uint32_t state[4], const unsigned char block[64]);
	static void Encode(unsigned char output, const apr_uint32_t input,
	unsigned int len);
	static void Decode(apr_uint32_t output, const unsigned char input,
	unsigned int len);

	static unsigned char PADDING[64] =
	{
	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
	};

	#if APR_CHARSET_EBCDIC
	static apr_xlate_t xlate_ebcdic_to_ascii; / used in apr_md4_encode() */
	#endif

	/* F, G and I are basic MD4 functions.
	*/
	#define F(x, y, z) (((x) & (y)) \| ((~x) & (z)))
	#define G(x, y, z) (((x) & (y)) \| ((x) & (z)) \| ((y) & (z)))
	#define H(x, y, z) ((x) ^ (y) ^ (z))

	/* ROTATE_LEFT rotates x left n bits.
	*/
	#define ROTATE_LEFT(x, n) (((x) << (n)) \| ((x) >> (32-(n))))

	/* FF, GG and HH are transformations for rounds 1, 2 and 3 */
	/* Rotation is separate from addition to prevent recomputation */

	#define FF(a, b, c, d, x, s) { \
	(a) += F ((b), (c), (d)) + (x); \
	(a) = ROTATE_LEFT ((a), (s)); \
	}
	#define GG(a, b, c, d, x, s) { \
	(a) += G ((b), (c), (d)) + (x) + (apr_uint32_t)0x5a827999; \
	(a) = ROTATE_LEFT ((a), (s)); \
	}
	#define HH(a, b, c, d, x, s) { \
	(a) += H ((b), (c), (d)) + (x) + (apr_uint32_t)0x6ed9eba1; \
	(a) = ROTATE_LEFT ((a), (s)); \
	}

	/* MD4 initialization. Begins an MD4 operation, writing a new context.
	*/
	APU_DECLARE(apr_status_t) apr_md4_init(apr_md4_ctx_t *context)
	{
	context->count[0] = context->count[1] = 0;

	/* Load magic initialization constants. */
	context->state[0] = 0x67452301;
	context->state[1] = 0xefcdab89;
	context->state[2] = 0x98badcfe;
	context->state[3] = 0x10325476;

	#if APR_HAS_XLATE
	context->xlate = NULL;
	#endif

	return APR_SUCCESS;
	}

	#if APR_HAS_XLATE
	/* MD4 translation setup. Provides the APR translation handle
	* to be used for translating the content before calculating the
	* digest.
	*/
	APU_DECLARE(apr_status_t) apr_md4_set_xlate(apr_md4_ctx_t *context,
	apr_xlate_t *xlate)
	{
	apr_status_t rv;
	int is_sb;

	/* TODO: remove the single-byte-only restriction from this code
	*/
	rv = apr_xlate_sb_get(xlate, &is_sb);
	if (rv != APR_SUCCESS) {
	return rv;
	}
	if (!is_sb) {
	return APR_EINVAL;
	}
	context->xlate = xlate;
	return APR_SUCCESS;
	}
	#endif /* APR_HAS_XLATE */

	/* MD4 block update operation. Continues an MD4 message-digest
	* operation, processing another message block, and updating the
	* context.
	*/
	APU_DECLARE(apr_status_t) apr_md4_update(apr_md4_ctx_t *context,
	const unsigned char *input,
	apr_size_t inputLen)
	{
	unsigned int i, idx, partLen;
	#if APR_HAS_XLATE
	apr_size_t inbytes_left, outbytes_left;
	#endif

	/* Compute number of bytes mod 64 */
	idx = (unsigned int)((context->count[0] >> 3) & 0x3F);

	/* Update number of bits */
	if ((context->count[0] += ((apr_uint32_t)inputLen << 3))
	< ((apr_uint32_t)inputLen << 3))
	context->count[1]++;
	context->count[1] += (apr_uint32_t)inputLen >> 29;

	partLen = 64 - idx;

	/* Transform as many times as possible. */
	#if !APR_HAS_XLATE
	if (inputLen >= partLen) {
	memcpy(&context->buffer[idx], input, partLen);
	MD4Transform(context->state, context->buffer);

	for (i = partLen; i + 63 < inputLen; i += 64)
	MD4Transform(context->state, &input[i]);

	idx = 0;
	}
	else
	i = 0;

	/* Buffer remaining input */
	memcpy(&context->buffer[idx], &input[i], inputLen - i);
	#else /APR_HAS_XLATE/
	if (inputLen >= partLen) {
	if (context->xlate) {
	inbytes_left = outbytes_left = partLen;
	apr_xlate_conv_buffer(context->xlate, (const char *)input,
	&inbytes_left,
	(char *)&context->buffer[idx],
	&outbytes_left);
	}
	else {
	memcpy(&context->buffer[idx], input, partLen);
	}
	MD4Transform(context->state, context->buffer);

	for (i = partLen; i + 63 < inputLen; i += 64) {
	if (context->xlate) {
	unsigned char inp_tmp[64];
	inbytes_left = outbytes_left = 64;
	apr_xlate_conv_buffer(context->xlate, (const char *)&input[i],
	&inbytes_left,
	(char *)inp_tmp, &outbytes_left);
	MD4Transform(context->state, inp_tmp);
	}
	else {
	MD4Transform(context->state, &input[i]);
	}
	}

	idx = 0;
	}
	else
	i = 0;

	/* Buffer remaining input */
	if (context->xlate) {
	inbytes_left = outbytes_left = inputLen - i;
	apr_xlate_conv_buffer(context->xlate, (const char *)&input[i],
	&inbytes_left, (char *)&context->buffer[idx],
	&outbytes_left);
	}
	else {
	memcpy(&context->buffer[idx], &input[i], inputLen - i);
	}
	#endif /APR_HAS_XLATE/
	return APR_SUCCESS;
	}

	/* MD4 finalization. Ends an MD4 message-digest operation, writing the
	* the message digest and zeroizing the context.
	*/
	APU_DECLARE(apr_status_t) apr_md4_final(
	unsigned char digest[APR_MD4_DIGESTSIZE],
	apr_md4_ctx_t *context)
	{
	unsigned char bits[8];
	unsigned int idx, padLen;

	/* Save number of bits */
	Encode(bits, context->count, 8);

	#if APR_HAS_XLATE
	/* apr_md4_update() should not translate for this final round. */
	context->xlate = NULL;
	#endif /APR_HAS_XLATE/

	/* Pad out to 56 mod 64. */
	idx = (unsigned int) ((context->count[0] >> 3) & 0x3f);
	padLen = (idx < 56) ? (56 - idx) : (120 - idx);
	apr_md4_update(context, PADDING, padLen);

	/* Append length (before padding) */
	apr_md4_update(context, bits, 8);

	/* Store state in digest */
	Encode(digest, context->state, APR_MD4_DIGESTSIZE);

	/* Zeroize sensitive information. */
	memset(context, 0, sizeof(*context));

	return APR_SUCCESS;
	}

	/* MD4 computation in one step (init, update, final)
	*/
	APU_DECLARE(apr_status_t) apr_md4(unsigned char digest[APR_MD4_DIGESTSIZE],
	const unsigned char *input,
	apr_size_t inputLen)
	{
	apr_md4_ctx_t ctx;
	apr_status_t rv;

	apr_md4_init(&ctx);

	if ((rv = apr_md4_update(&ctx, input, inputLen)) != APR_SUCCESS)
	return rv;

	return apr_md4_final(digest, &ctx);
	}

	/* MD4 basic transformation. Transforms state based on block. */
	static void MD4Transform(apr_uint32_t state[4], const unsigned char block[64])
	{
	apr_uint32_t a = state[0], b = state[1], c = state[2], d = state[3],
	x[APR_MD4_DIGESTSIZE];

	Decode(x, block, 64);

	/* Round 1 */
	FF (a, b, c, d, x[ 0], S11); /* 1 */
	FF (d, a, b, c, x[ 1], S12); /* 2 */
	FF (c, d, a, b, x[ 2], S13); /* 3 */
	FF (b, c, d, a, x[ 3], S14); /* 4 */
	FF (a, b, c, d, x[ 4], S11); /* 5 */
	FF (d, a, b, c, x[ 5], S12); /* 6 */
	FF (c, d, a, b, x[ 6], S13); /* 7 */
	FF (b, c, d, a, x[ 7], S14); /* 8 */
	FF (a, b, c, d, x[ 8], S11); /* 9 */
	FF (d, a, b, c, x[ 9], S12); /* 10 */
	FF (c, d, a, b, x[10], S13); /* 11 */
	FF (b, c, d, a, x[11], S14); /* 12 */
	FF (a, b, c, d, x[12], S11); /* 13 */
	FF (d, a, b, c, x[13], S12); /* 14 */
	FF (c, d, a, b, x[14], S13); /* 15 */
	FF (b, c, d, a, x[15], S14); /* 16 */

	/* Round 2 */
	GG (a, b, c, d, x[ 0], S21); /* 17 */
	GG (d, a, b, c, x[ 4], S22); /* 18 */
	GG (c, d, a, b, x[ 8], S23); /* 19 */
	GG (b, c, d, a, x[12], S24); /* 20 */
	GG (a, b, c, d, x[ 1], S21); /* 21 */
	GG (d, a, b, c, x[ 5], S22); /* 22 */
	GG (c, d, a, b, x[ 9], S23); /* 23 */
	GG (b, c, d, a, x[13], S24); /* 24 */
	GG (a, b, c, d, x[ 2], S21); /* 25 */
	GG (d, a, b, c, x[ 6], S22); /* 26 */
	GG (c, d, a, b, x[10], S23); /* 27 */
	GG (b, c, d, a, x[14], S24); /* 28 */
	GG (a, b, c, d, x[ 3], S21); /* 29 */
	GG (d, a, b, c, x[ 7], S22); /* 30 */
	GG (c, d, a, b, x[11], S23); /* 31 */
	GG (b, c, d, a, x[15], S24); /* 32 */

	/* Round 3 */
	HH (a, b, c, d, x[ 0], S31); /* 33 */
	HH (d, a, b, c, x[ 8], S32); /* 34 */
	HH (c, d, a, b, x[ 4], S33); /* 35 */
	HH (b, c, d, a, x[12], S34); /* 36 */
	HH (a, b, c, d, x[ 2], S31); /* 37 */
	HH (d, a, b, c, x[10], S32); /* 38 */
	HH (c, d, a, b, x[ 6], S33); /* 39 */
	HH (b, c, d, a, x[14], S34); /* 40 */
	HH (a, b, c, d, x[ 1], S31); /* 41 */
	HH (d, a, b, c, x[ 9], S32); /* 42 */
	HH (c, d, a, b, x[ 5], S33); /* 43 */
	HH (b, c, d, a, x[13], S34); /* 44 */
	HH (a, b, c, d, x[ 3], S31); /* 45 */
	HH (d, a, b, c, x[11], S32); /* 46 */
	HH (c, d, a, b, x[ 7], S33); /* 47 */
	HH (b, c, d, a, x[15], S34); /* 48 */

	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;

	/* Zeroize sensitive information. */
	memset(x, 0, sizeof(x));
	}

	/* Encodes input (apr_uint32_t) into output (unsigned char). Assumes len is
	* a multiple of 4.
	*/
	static void Encode(unsigned char output, const apr_uint32_t input,
	unsigned int len)
	{
	unsigned int i, j;
	apr_uint32_t k;

	for (i = 0, j = 0; j < len; i++, j += 4) {
	k = input[i];
	output[j] = (unsigned char)(k & 0xff);
	output[j + 1] = (unsigned char)((k >> 8) & 0xff);
	output[j + 2] = (unsigned char)((k >> 16) & 0xff);
	output[j + 3] = (unsigned char)((k >> 24) & 0xff);
	}
	}

	/* Decodes input (unsigned char) into output (apr_uint32_t). Assumes len is
	* a multiple of 4.
	*/
	static void Decode(apr_uint32_t output, const unsigned char input,
	unsigned int len)
	{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
	output[i] = ((apr_uint32_t)input[j]) \|
	(((apr_uint32_t)input[j + 1]) << 8) \|
	(((apr_uint32_t)input[j + 2]) << 16) \|
	(((apr_uint32_t)input[j + 3]) << 24);
	}

	#if APR_CHARSET_EBCDIC
	APU_DECLARE(apr_status_t) apr_MD4InitEBCDIC(apr_xlate_t *xlate)
	{
	xlate_ebcdic_to_ascii = xlate;
	return APR_SUCCESS;
	}
	#endif