From: hno <>
Date: Sun, 11 Jun 2006 19:29:00 +0000 (+0000)
Subject: Bug #1490: GPL license issues with RSA MD5 implementation
X-Git-Tag: SQUID_3_0_PRE4~29
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a34ac43400ab00d094ef73d4d29a5e432b126101;p=thirdparty%2Fsquid.git

Bug #1490: GPL license issues with RSA MD5 implementation

replaced the Squid provided MD5 with another public domain copy not
encumbered by the RSA license.
---

diff --git a/include/md5.h b/include/md5.h
index 70a370bbd0..bf72f001fc 100644
--- a/include/md5.h
+++ b/include/md5.h
@@ -1,7 +1,3 @@
-/*
- * $Id: md5.h,v 1.15 2003/01/23 00:36:47 robertc Exp $
- */
-
 #ifndef SQUID_MD5_H
 #define SQUID_MD5_H
 
@@ -27,46 +23,47 @@
 
 #else /* USE_OPENSSL */
 
-/* MD5.H - header file for MD5C.C
- */
-
-/* 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. MD5 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. MD5 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.
+/*
+ * This is the header file for the MD5 message-digest algorithm.
+ * The algorithm is due to Ron Rivest.  This code was
+ * written by Colin Plumb in 1993, no copyright is claimed.
+ * This code is in the public domain; do with it what you wish.
+ *
+ * Equivalent code is available from RSA Data Security, Inc.
+ * This code has been tested against that, and is equivalent,
+ * except that you don't need to include two pages of legalese
+ * with every copy.
+ *
+ * To compute the message digest of a chunk of bytes, declare an
+ * MD5Context structure, pass it to MD5Init, call MD5Update as
+ * needed on buffers full of bytes, and then call MD5Final, which
+ * will fill a supplied 16-byte array with the digest.
+ *
+ * Changed so as no longer to depend on Colin Plumb's `usual.h'
+ * header definitions; now uses stuff from dpkg's config.h
+ *  - Ian Jackson <ian@chiark.greenend.org.uk>.
+ * Still in the public domain.
+ *
+ * Changed MD5Update to take a void * for easier use and some other
+ * minor cleanup. - Henrik Nordstrom <henrik@henriknordstrom.net>.
+ * Still in the public domain.
+ *
  */
 
-#include "config.h"
+#include "squid_types.h"
 
-/* MD5 context. */
-typedef struct {
-    u_int32_t state[4];		/* state (ABCD) */
-    u_int32_t count[2];		/* number of bits, modulo 2^64 (lsb first) */
-    unsigned char buffer[64];	/* input buffer */
+typedef struct MD5Context {
+    uint32_t buf[4];
+    uint32_t bytes[2];
+    uint32_t in[16];
 } MD5_CTX;
 
-SQUIDCEXTERN void MD5Init(MD5_CTX *);
-SQUIDCEXTERN void MD5Update(MD5_CTX *, const void *, unsigned long);
-SQUIDCEXTERN void MD5Final(unsigned char *, MD5_CTX *);
+SQUIDCEXTERN void MD5Init(struct MD5Context *context);
+SQUIDCEXTERN void MD5Update(struct MD5Context *context, const void *buf, unsigned len);
+SQUIDCEXTERN void MD5Final(uint8_t digest[16], struct MD5Context *context);
+SQUIDCEXTERN void MD5Transform(uint32_t buf[4], uint32_t const in[16]);
 
 #define MD5_DIGEST_CHARS         16
 
 #endif /* USE_OPENSSL */
-
 #endif /* SQUID_MD5_H */
diff --git a/lib/md5.c b/lib/md5.c
index 88a017b553..beb3dc6afb 100644
--- a/lib/md5.c
+++ b/lib/md5.c
@@ -1,356 +1,259 @@
 /*
- * $Id: md5.c,v 1.16 2003/01/23 00:37:01 robertc Exp $
+ * This code implements the MD5 message-digest algorithm.
+ * The algorithm is due to Ron Rivest.  This code was
+ * written by Colin Plumb in 1993, no copyright is claimed.
+ * This code is in the public domain; do with it what you wish.
+ *
+ * Equivalent code is available from RSA Data Security, Inc.
+ * This code has been tested against that, and is equivalent,
+ * except that you don't need to include two pages of legalese
+ * with every copy.
+ *
+ * To compute the message digest of a chunk of bytes, declare an
+ * MD5Context structure, pass it to MD5Init, call MD5Update as
+ * needed on buffers full of bytes, and then call MD5Final, which
+ * will fill a supplied 16-byte array with the digest.
+ *
+ * Changed so as no longer to depend on Colin Plumb's `usual.h' header
+ * definitions; now uses stuff from dpkg's config.h.
+ *  - Ian Jackson <ian@chiark.greenend.org.uk>.
+ * Still in the public domain.
+ *
+ * Changed MD5Update to take a void * for easier use and some other
+ * minor cleanup. - Henrik Nordstrom <henrik@henriknordstrom.net>.
+ * Still in the public domain.
+ *
  */
+#include "config.h"
 
-/* taken from RFC-1321/Appendix A.3 */
-
-/*
- * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
- */
-
-/*
- * 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. MD5 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. MD5
- * 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.
+/* MS VisualStudio Projects are monolithic, so we need the following
+ * #if to exclude the MD5 code from compile process when we are
+ * building the SSL support.
  */
-
-#include "md5.h"
-
+#if !USE_SSL
 #if HAVE_STRING_H
-#include <string.h>
+#include <string.h>		/* for memcpy() */
 #endif
-
-/*
- * Constants for MD5Transform routine.
- */
-#define S11 7
-#define S12 12
-#define S13 17
-#define S14 22
-#define S21 5
-#define S22 9
-#define S23 14
-#define S24 20
-#define S31 4
-#define S32 11
-#define S33 16
-#define S34 23
-#define S41 6
-#define S42 10
-#define S43 15
-#define S44 21
-
-static void MD5Transform(u_int32_t[4], const unsigned char[64]);
-static void Encode(unsigned char *, u_int32_t *, unsigned int);
-static void Decode(u_int32_t *, const unsigned char *, unsigned int);
-
-#if HAVE_MEMCPY
-#define MD5_memcpy(to,from,count) memcpy(to,from,count)
-#else
-static void MD5_memcpy(unsigned char *, unsigned char *, unsigned int);
+#if HAVE_SYS_TYPES_H
+#include <sys/types.h>		/* for stupid systems */
 #endif
-
-#if HAVE_MEMSET
-#define MD5_memset(buf,chr,count) memset(buf,chr,count)
-#else
-static void MD5_memset(char *, int, unsigned int);
+#if HAVE_NETINET_IN_H
+#include <netinet/in.h>		/* for ntohl() */
 #endif
 
-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
-};
-
-/*
- * F, G, H and I are basic MD5 functions.
- */
-#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
-#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
-#define H(x, y, z) ((x) ^ (y) ^ (z))
-#define I(x, y, z) ((y) ^ ((x) | (~z)))
-
-/*
- * ROTATE_LEFT rotates x left n bits.
- */
-#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
-
-/*
- * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. Rotation is
- * separate from addition to prevent recomputation.
- */
-#define FF(a, b, c, d, x, s, ac) { \
- (a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
-#define GG(a, b, c, d, x, s, ac) { \
- (a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
-#define HH(a, b, c, d, x, s, ac) { \
- (a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
-#define II(a, b, c, d, x, s, ac) { \
- (a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
+#include "md5.h"
 
-/*
- * MD5 initialization. Begins an MD5 operation, writing a new context.
- */
+#ifdef WORDS_BIGENDIAN
 void
-MD5Init(MD5_CTX * context)
+byteSwap(uint32_t * buf, unsigned words)
 {
-    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;
+    uint8_t *p = (uint8_t *) buf;
+
+    do {
+	*buf++ = (uint32_t) ((unsigned) p[3] << 8 | p[2]) << 16 |
+	    ((unsigned) p[1] << 8 | p[0]);
+	p += 4;
+    } while (--words);
 }
+#else
+#define byteSwap(buf,words)
+#endif
 
 /*
- * MD5 block update operation. Continues an MD5 message-digest operation,
- * processing another message block, and updating the context.
+ * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
+ * initialization constants.
  */
 void
-MD5Update(MD5_CTX * context, const void *input_p, unsigned long inputLen)
+MD5Init(struct MD5Context *ctx)
 {
-    unsigned int i, index, partLen;
-    const unsigned char *input = input_p;
-
-    /* Compute number of bytes mod 64 */
-    index = (unsigned int) ((context->count[0] >> 3) & 0x3F);
-
-    /* Update number of bits */
-    if ((context->count[0] += ((u_int32_t) inputLen << 3))
-	< ((u_int32_t) inputLen << 3))
-	context->count[1]++;
-    context->count[1] += ((u_int32_t) inputLen >> 29);
-
-    partLen = 64 - index;
+    ctx->buf[0] = 0x67452301;
+    ctx->buf[1] = 0xefcdab89;
+    ctx->buf[2] = 0x98badcfe;
+    ctx->buf[3] = 0x10325476;
 
-    /*
-     * Transform as many times as possible.
-     */
-    if (inputLen >= partLen) {
-	MD5_memcpy(&context->buffer[index], input, partLen);
-	MD5Transform(context->state, context->buffer);
-
-	for (i = partLen; i + 63 < inputLen; i += 64)
-	    MD5Transform(context->state, &input[i]);
-
-	index = 0;
-    } else
-	i = 0;
-
-    /* Buffer remaining input */
-    MD5_memcpy(&context->buffer[index], &input[i], inputLen - i);
+    ctx->bytes[0] = 0;
+    ctx->bytes[1] = 0;
 }
 
 /*
- * MD5 finalization. Ends an MD5 message-digest operation, writing the the
- * message digest and zeroizing the context.
+ * Update context to reflect the concatenation of another buffer full
+ * of bytes.
  */
 void
-MD5Final(unsigned char *digest, MD5_CTX * context)
+MD5Update(struct MD5Context *ctx, const void *_buf, unsigned len)
 {
-    unsigned char bits[8];
-    unsigned int index, padLen;
+    uint8_t const *buf = _buf;
+    uint32_t t;
 
-    /* Save number of bits */
-    Encode(bits, context->count, 8);
+    /* Update byte count */
 
-    /*
-     * Pad out to 56 mod 64.
-     */
-    index = (unsigned int) ((context->count[0] >> 3) & 0x3f);
-    padLen = (index < 56) ? (56 - index) : (120 - index);
-    MD5Update(context, PADDING, padLen);
+    t = ctx->bytes[0];
+    if ((ctx->bytes[0] = t + len) < t)
+	ctx->bytes[1]++;	/* Carry from low to high */
 
-    /* Append length (before padding) */
-    MD5Update(context, bits, 8);
-    /* Store state in digest */
-    Encode(digest, context->state, 16);
+    t = 64 - (t & 0x3f);	/* Space available in ctx->in (at least 1) */
+    if (t > len) {
+	memcpy((uint8_t *) ctx->in + 64 - t, buf, len);
+	return;
+    }
+    /* First chunk is an odd size */
+    memcpy((uint8_t *) ctx->in + 64 - t, buf, t);
+    byteSwap(ctx->in, 16);
+    MD5Transform(ctx->buf, ctx->in);
+    buf += t;
+    len -= t;
+
+    /* Process data in 64-byte chunks */
+    while (len >= 64) {
+	memcpy(ctx->in, buf, 64);
+	byteSwap(ctx->in, 16);
+	MD5Transform(ctx->buf, ctx->in);
+	buf += 64;
+	len -= 64;
+    }
 
-    /*
-     * Zeroize sensitive information.
-     */
-    MD5_memset((char *) context, 0, sizeof(*context));
+    /* Handle any remaining bytes of data. */
+    memcpy(ctx->in, buf, len);
 }
 
 /*
- * MD5 basic transformation. Transforms state based on block.
+ * Final wrapup - pad to 64-byte boundary with the bit pattern 
+ * 1 0* (64-bit count of bits processed, MSB-first)
  */
-static void
-MD5Transform(u_int32_t state[4], const unsigned char block[64])
+void
+MD5Final(unsigned char digest[16], struct MD5Context *ctx)
 {
-    u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
-
-    Decode(x, block, 64);
-
-    /* Round 1 */
-    FF(a, b, c, d, x[0], S11, 0xd76aa478);	/* 1 */
-    FF(d, a, b, c, x[1], S12, 0xe8c7b756);	/* 2 */
-    FF(c, d, a, b, x[2], S13, 0x242070db);	/* 3 */
-    FF(b, c, d, a, x[3], S14, 0xc1bdceee);	/* 4 */
-    FF(a, b, c, d, x[4], S11, 0xf57c0faf);	/* 5 */
-    FF(d, a, b, c, x[5], S12, 0x4787c62a);	/* 6 */
-    FF(c, d, a, b, x[6], S13, 0xa8304613);	/* 7 */
-    FF(b, c, d, a, x[7], S14, 0xfd469501);	/* 8 */
-    FF(a, b, c, d, x[8], S11, 0x698098d8);	/* 9 */
-    FF(d, a, b, c, x[9], S12, 0x8b44f7af);	/* 10 */
-    FF(c, d, a, b, x[10], S13, 0xffff5bb1);	/* 11 */
-    FF(b, c, d, a, x[11], S14, 0x895cd7be);	/* 12 */
-    FF(a, b, c, d, x[12], S11, 0x6b901122);	/* 13 */
-    FF(d, a, b, c, x[13], S12, 0xfd987193);	/* 14 */
-    FF(c, d, a, b, x[14], S13, 0xa679438e);	/* 15 */
-    FF(b, c, d, a, x[15], S14, 0x49b40821);	/* 16 */
+    int count = ctx->bytes[0] & 0x3f;	/* Number of bytes in ctx->in */
+    uint8_t *p = (uint8_t *) ctx->in + count;
 
-    /* Round 2 */
-    GG(a, b, c, d, x[1], S21, 0xf61e2562);	/* 17 */
-    GG(d, a, b, c, x[6], S22, 0xc040b340);	/* 18 */
-    GG(c, d, a, b, x[11], S23, 0x265e5a51);	/* 19 */
-    GG(b, c, d, a, x[0], S24, 0xe9b6c7aa);	/* 20 */
-    GG(a, b, c, d, x[5], S21, 0xd62f105d);	/* 21 */
-    GG(d, a, b, c, x[10], S22, 0x2441453);	/* 22 */
-    GG(c, d, a, b, x[15], S23, 0xd8a1e681);	/* 23 */
-    GG(b, c, d, a, x[4], S24, 0xe7d3fbc8);	/* 24 */
-    GG(a, b, c, d, x[9], S21, 0x21e1cde6);	/* 25 */
-    GG(d, a, b, c, x[14], S22, 0xc33707d6);	/* 26 */
-    GG(c, d, a, b, x[3], S23, 0xf4d50d87);	/* 27 */
-    GG(b, c, d, a, x[8], S24, 0x455a14ed);	/* 28 */
-    GG(a, b, c, d, x[13], S21, 0xa9e3e905);	/* 29 */
-    GG(d, a, b, c, x[2], S22, 0xfcefa3f8);	/* 30 */
-    GG(c, d, a, b, x[7], S23, 0x676f02d9);	/* 31 */
-    GG(b, c, d, a, x[12], S24, 0x8d2a4c8a);	/* 32 */
+    /* Set the first char of padding to 0x80.  There is always room. */
+    *p++ = 0x80;
 
-    /* Round 3 */
-    HH(a, b, c, d, x[5], S31, 0xfffa3942);	/* 33 */
-    HH(d, a, b, c, x[8], S32, 0x8771f681);	/* 34 */
-    HH(c, d, a, b, x[11], S33, 0x6d9d6122);	/* 35 */
-    HH(b, c, d, a, x[14], S34, 0xfde5380c);	/* 36 */
-    HH(a, b, c, d, x[1], S31, 0xa4beea44);	/* 37 */
-    HH(d, a, b, c, x[4], S32, 0x4bdecfa9);	/* 38 */
-    HH(c, d, a, b, x[7], S33, 0xf6bb4b60);	/* 39 */
-    HH(b, c, d, a, x[10], S34, 0xbebfbc70);	/* 40 */
-    HH(a, b, c, d, x[13], S31, 0x289b7ec6);	/* 41 */
-    HH(d, a, b, c, x[0], S32, 0xeaa127fa);	/* 42 */
-    HH(c, d, a, b, x[3], S33, 0xd4ef3085);	/* 43 */
-    HH(b, c, d, a, x[6], S34, 0x4881d05);	/* 44 */
-    HH(a, b, c, d, x[9], S31, 0xd9d4d039);	/* 45 */
-    HH(d, a, b, c, x[12], S32, 0xe6db99e5);	/* 46 */
-    HH(c, d, a, b, x[15], S33, 0x1fa27cf8);	/* 47 */
-    HH(b, c, d, a, x[2], S34, 0xc4ac5665);	/* 48 */
+    /* Bytes of padding needed to make 56 bytes (-8..55) */
+    count = 56 - 1 - count;
 
-    /* Round 4 */
-    II(a, b, c, d, x[0], S41, 0xf4292244);	/* 49 */
-    II(d, a, b, c, x[7], S42, 0x432aff97);	/* 50 */
-    II(c, d, a, b, x[14], S43, 0xab9423a7);	/* 51 */
-    II(b, c, d, a, x[5], S44, 0xfc93a039);	/* 52 */
-    II(a, b, c, d, x[12], S41, 0x655b59c3);	/* 53 */
-    II(d, a, b, c, x[3], S42, 0x8f0ccc92);	/* 54 */
-    II(c, d, a, b, x[10], S43, 0xffeff47d);	/* 55 */
-    II(b, c, d, a, x[1], S44, 0x85845dd1);	/* 56 */
-    II(a, b, c, d, x[8], S41, 0x6fa87e4f);	/* 57 */
-    II(d, a, b, c, x[15], S42, 0xfe2ce6e0);	/* 58 */
-    II(c, d, a, b, x[6], S43, 0xa3014314);	/* 59 */
-    II(b, c, d, a, x[13], S44, 0x4e0811a1);	/* 60 */
-    II(a, b, c, d, x[4], S41, 0xf7537e82);	/* 61 */
-    II(d, a, b, c, x[11], S42, 0xbd3af235);	/* 62 */
-    II(c, d, a, b, x[2], S43, 0x2ad7d2bb);	/* 63 */
-    II(b, c, d, a, x[9], S44, 0xeb86d391);	/* 64 */
+    if (count < 0) {		/* Padding forces an extra block */
+	memset(p, 0, count + 8);
+	byteSwap(ctx->in, 16);
+	MD5Transform(ctx->buf, ctx->in);
+	p = (uint8_t *) ctx->in;
+	count = 56;
+    }
+    memset(p, 0, count);
+    byteSwap(ctx->in, 14);
 
-    state[0] += a;
-    state[1] += b;
-    state[2] += c;
-    state[3] += d;
+    /* Append length in bits and transform */
+    ctx->in[14] = ctx->bytes[0] << 3;
+    ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
+    MD5Transform(ctx->buf, ctx->in);
 
-    /*
-     * Zeroize sensitive information.
-     */
-    MD5_memset((char *) x, 0, sizeof(x));
+    byteSwap(ctx->buf, 4);
+    memcpy(digest, ctx->buf, 16);
+    memset(ctx, 0, sizeof(ctx));	/* In case it's sensitive */
 }
 
-/*
- * Encodes input (u_int32_t) into output (unsigned char). Assumes len is a
- * multiple of 4.
- */
-static void
-Encode(unsigned char *output, u_int32_t * input, unsigned int len)
-{
-    unsigned int i, j;
+#ifndef ASM_MD5
 
-    for (i = 0, j = 0; j < len; i++, j += 4) {
-	output[j] = (unsigned char) (input[i] & 0xff);
-	output[j + 1] = (unsigned char) ((input[i] >> 8) & 0xff);
-	output[j + 2] = (unsigned char) ((input[i] >> 16) & 0xff);
-	output[j + 3] = (unsigned char) ((input[i] >> 24) & 0xff);
-    }
-}
+/* The four core functions - F1 is optimized somewhat */
 
-/*
- * Decodes input (unsigned char) into output (u_int32_t). Assumes len is a
- * multiple of 4.
- */
-static void
-Decode(u_int32_t * output, const unsigned char *input, unsigned int len)
-{
-    unsigned int i, j;
+/* #define F1(x, y, z) (x & y | ~x & z) */
+#define F1(x, y, z) (z ^ (x & (y ^ z)))
+#define F2(x, y, z) F1(z, x, y)
+#define F3(x, y, z) (x ^ y ^ z)
+#define F4(x, y, z) (y ^ (x | ~z))
 
-    for (i = 0, j = 0; j < len; i++, j += 4)
-	output[i] = ((u_int32_t) input[j]) | (((u_int32_t) input[j + 1]) << 8) |
-	    (((u_int32_t) input[j + 2]) << 16) | (((u_int32_t) input[j + 3]) << 24);
-}
+/* This is the central step in the MD5 algorithm. */
+#define MD5STEP(f,w,x,y,z,in,s) \
+	 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
 
-#if !HAVE_MEMCPY
 /*
- * Note: Replace "for loop" with standard memcpy if possible.
+ * The core of the MD5 algorithm, this alters an existing MD5 hash to
+ * reflect the addition of 16 longwords of new data.  MD5Update blocks
+ * the data and converts bytes into longwords for this routine.
  */
-
-static void
-MD5_memcpy(unsigned char *output, unsigned char *input, unsigned int len)
-{
-    unsigned int i;
-    for (i = 0; i < len; i++)
-	output[i] = input[i];
-}
-#endif
-
-#if !HAVE_MEMSET
-/*
- * Note: Replace "for loop" with standard memset if possible.
- */
-static void
-MD5_memset(char *output, int value, unsigned int len)
+void
+MD5Transform(uint32_t buf[4], uint32_t const in[16])
 {
-    unsigned int i;
-    for (i = 0; i < len; i++)
-	output[i] = (char) value;
+    register uint32_t a, b, c, d;
+
+    a = buf[0];
+    b = buf[1];
+    c = buf[2];
+    d = buf[3];
+
+    MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
+    MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
+    MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
+    MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
+    MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
+    MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
+    MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
+    MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
+    MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
+    MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
+    MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
+    MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
+    MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
+    MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
+    MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
+    MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
+
+    MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
+    MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
+    MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
+    MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
+    MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
+    MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
+    MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
+    MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
+    MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
+    MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
+    MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
+    MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
+    MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
+    MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
+    MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
+    MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
+
+    MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
+    MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
+    MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
+    MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
+    MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
+    MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
+    MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
+    MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
+    MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
+    MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
+    MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
+    MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
+    MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
+    MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
+    MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
+    MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
+
+    MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
+    MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
+    MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
+    MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
+    MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
+    MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
+    MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
+    MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
+    MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
+    MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
+    MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
+    MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
+    MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
+    MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
+    MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
+    MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
+
+    buf[0] += a;
+    buf[1] += b;
+    buf[2] += c;
+    buf[3] += d;
 }
 
 #endif
+#endif