MD5: replace implementation

The previous one was "encumbered" by RSA Inc - to avoid the licensing
restrictions it has being replaced. This is the initial import,
inserting the md5.c and md5.h files from
http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5

Code-by: Alexander Peslyak

1 files changed, 273 insertions, 269 deletions

diff --git a/lib/md5.c b/lib/md5.c
index b0577cdfd..c2185857c 100644
--- a/lib/md5.c
+++ b/lib/md5.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2012, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -159,305 +159,309 @@ static void MD5_Final(unsigned char digest[16], MD5_CTX *ctx)
 
 #else
 /* When no other crypto library is available we use this code segment */
-
-/* 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 an OpenSSL-compatible implementation of the RSA Data Security, Inc.
+ * MD5 Message-Digest Algorithm (RFC 1321).
+ *
+ * Homepage:
+ http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5
+ *
+ * Author:
+ * Alexander Peslyak, better known as Solar Designer <solar at openwall.com>
+ *
+ * This software was written by Alexander Peslyak in 2001.  No copyright is
+ * claimed, and the software is hereby placed in the public domain.
+ * In case this attempt to disclaim copyright and place the software in the
+ * public domain is deemed null and void, then the software is
+ * Copyright (c) 2001 Alexander Peslyak and it is hereby released to the
+ * general public under the following terms:
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted.
+ *
+ * There's ABSOLUTELY NO WARRANTY, express or implied.
+ *
+ * (This is a heavily cut-down "BSD license".)
+ *
+ * This differs from Colin Plumb's older public domain implementation in that
+ * no exactly 32-bit integer data type is required (any 32-bit or wider
+ * unsigned integer data type will do), there's no compile-time endianness
+ * configuration, and the function prototypes match OpenSSL's.  No code from
+ * Colin Plumb's implementation has been reused; this comment merely compares
+ * the properties of the two independent implementations.
+ *
+ * The primary goals of this implementation are portability and ease of use.
+ * It is meant to be fast, but not as fast as possible.  Some known
+ * optimizations are not included to reduce source code size and avoid
+ * compile-time configuration.
  */
 
-/* UINT4 defines a four byte word */
-typedef unsigned int UINT4;
-
-/* MD5 context. */
-struct md5_ctx {
-  UINT4 state[4];                                   /* state (ABCD) */
-  UINT4 count[2];        /* number of bits, modulo 2^64 (lsb first) */
-  unsigned char buffer[64];                         /* input buffer */
-};
+#include <string.h>
 
-typedef struct md5_ctx MD5_CTX;
+/* Any 32-bit or wider unsigned integer data type will do */
+typedef unsigned int MD5_u32plus;
 
-static void MD5_Init(struct md5_ctx *);
-static void MD5_Update(struct md5_ctx *, const unsigned char *, unsigned int);
-static void MD5_Final(unsigned char [16], struct md5_ctx *);
-
-/* Constants for MD5Transform routine.
- */
+typedef struct {
+  MD5_u32plus lo, hi;
+  MD5_u32plus a, b, c, d;
+  unsigned char buffer[64];
+  MD5_u32plus block[16];
+} MD5_CTX;
 
-#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(UINT4 [4], const unsigned char [64]);
-static void Encode(unsigned char *, UINT4 *, unsigned int);
-static void Decode(UINT4 *, const unsigned char *, unsigned int);
-
-static const 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
-};
+extern void MD5_Init(MD5_CTX *ctx);
+extern void MD5_Update(MD5_CTX *ctx, const void *data, unsigned long size);
+extern void MD5_Final(unsigned char *result, MD5_CTX *ctx);
 
-/* F, G, H and I are basic MD5 functions.
+/*
+ * The basic MD5 functions.
+ *
+ * F and G are optimized compared to their RFC 1321 definitions for
+ * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
+ * implementation.
  */
-#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)))
+#define F(x, y, z)			((z) ^ ((x) & ((y) ^ (z))))
+#define G(x, y, z)			((y) ^ ((z) & ((x) ^ (y))))
+#define H(x, y, z)			(((x) ^ (y)) ^ (z))
+#define H2(x, y, z)			((x) ^ ((y) ^ (z)))
+#define I(x, y, z)			((y) ^ ((x) | ~(z)))
 
-/* ROTATE_LEFT rotates x left n bits.
+/*
+ * The MD5 transformation for all four rounds.
  */
-#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
+#define STEP(f, a, b, c, d, x, t, s) \
+	(a) += f((b), (c), (d)) + (x) + (t); \
+	(a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \
+	(a) += (b);
 
-/* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
-Rotation is separate from addition to prevent recomputation.
+/*
+ * SET reads 4 input bytes in little-endian byte order and stores them
+ * in a properly aligned word in host byte order.
+ *
+ * The check for little-endian architectures that tolerate unaligned
+ * memory accesses is just an optimization.  Nothing will break if it
+ * doesn't work.
  */
-#define FF(a, b, c, d, x, s, ac) { \
- (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
-#define GG(a, b, c, d, x, s, ac) { \
- (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
-#define HH(a, b, c, d, x, s, ac) { \
- (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
-#define II(a, b, c, d, x, s, ac) { \
- (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
- (a) = ROTATE_LEFT ((a), (s)); \
- (a) += (b); \
-  }
+#if defined(__i386__) || defined(__x86_64__) || defined(__vax__)
+#define SET(n) \
+	(*(MD5_u32plus *)&ptr[(n) * 4])
+#define GET(n) \
+	SET(n)
+#else
+#define SET(n) \
+	(ctx->block[(n)] = \
+	(MD5_u32plus)ptr[(n) * 4] | \
+	((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \
+	((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \
+	((MD5_u32plus)ptr[(n) * 4 + 3] << 24))
+#define GET(n) \
+	(ctx->block[(n)])
+#endif
 
-/* MD5 initialization. Begins an MD5 operation, writing a new context.
+/*
+ * This processes one or more 64-byte data blocks, but does NOT update
+ * the bit counters.  There are no alignment requirements.
  */
-static void MD5_Init(struct md5_ctx *context)
+static const void *body(MD5_CTX *ctx, const void *data, unsigned long size)
 {
-  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;
+	const unsigned char *ptr;
+	MD5_u32plus a, b, c, d;
+	MD5_u32plus saved_a, saved_b, saved_c, saved_d;
+
+	ptr = (const unsigned char *)data;
+
+	a = ctx->a;
+	b = ctx->b;
+	c = ctx->c;
+	d = ctx->d;
+
+	do {
+		saved_a = a;
+		saved_b = b;
+		saved_c = c;
+		saved_d = d;
+
+/* Round 1 */
+		STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
+		STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
+		STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
+		STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
+		STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
+		STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
+		STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
+		STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
+		STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
+		STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
+		STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
+		STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
+		STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
+		STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
+		STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
+		STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
+
+/* Round 2 */
+		STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
+		STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
+		STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
+		STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
+		STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
+		STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
+		STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
+		STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
+		STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
+		STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
+		STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
+		STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
+		STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
+		STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
+		STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
+		STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
+
+/* Round 3 */
+		STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
+		STEP(H2, d, a, b, c, GET(8), 0x8771f681, 11)
+		STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
+		STEP(H2, b, c, d, a, GET(14), 0xfde5380c, 23)
+		STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
+		STEP(H2, d, a, b, c, GET(4), 0x4bdecfa9, 11)
+		STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
+		STEP(H2, b, c, d, a, GET(10), 0xbebfbc70, 23)
+		STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
+		STEP(H2, d, a, b, c, GET(0), 0xeaa127fa, 11)
+		STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
+		STEP(H2, b, c, d, a, GET(6), 0x04881d05, 23)
+		STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
+		STEP(H2, d, a, b, c, GET(12), 0xe6db99e5, 11)
+		STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
+		STEP(H2, b, c, d, a, GET(2), 0xc4ac5665, 23)
+
+/* Round 4 */
+		STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
+		STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
+		STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
+		STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
+		STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
+		STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
+		STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
+		STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
+		STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
+		STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
+		STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
+		STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
+		STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
+		STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
+		STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
+		STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
+
+		a += saved_a;
+		b += saved_b;
+		c += saved_c;
+		d += saved_d;
+
+		ptr += 64;
+	} while (size -= 64);
+
+	ctx->a = a;
+	ctx->b = b;
+	ctx->c = c;
+	ctx->d = d;
+
+	return ptr;
 }
 
-/* MD5 block update operation. Continues an MD5 message-digest
-  operation, processing another message block, and updating the
-  context.
- */
-static void MD5_Update (struct md5_ctx *context,    /* context */
-                        const unsigned char *input, /* input block */
-                        unsigned int inputLen)      /* length of input block */
+void MD5_Init(MD5_CTX *ctx)
 {
-  unsigned int i, bufindex, partLen;
-
-  /* Compute number of bytes mod 64 */
-  bufindex = (unsigned int)((context->count[0] >> 3) & 0x3F);
-
-  /* Update number of bits */
-  if((context->count[0] += ((UINT4)inputLen << 3))
-      < ((UINT4)inputLen << 3))
-    context->count[1]++;
-  context->count[1] += ((UINT4)inputLen >> 29);
-
-  partLen = 64 - bufindex;
-
-  /* Transform as many times as possible. */
-  if(inputLen >= partLen) {
-    memcpy(&context->buffer[bufindex], input, partLen);
-    MD5Transform(context->state, context->buffer);
-
-    for(i = partLen; i + 63 < inputLen; i += 64)
-      MD5Transform(context->state, &input[i]);
+	ctx->a = 0x67452301;
+	ctx->b = 0xefcdab89;
+	ctx->c = 0x98badcfe;
+	ctx->d = 0x10325476;
 
-    bufindex = 0;
-  }
-  else
-    i = 0;
-
-  /* Buffer remaining input */
-  memcpy(&context->buffer[bufindex], &input[i], inputLen-i);
+	ctx->lo = 0;
+	ctx->hi = 0;
 }
 
-/* MD5 finalization. Ends an MD5 message-digest operation, writing the
-   the message digest and zeroizing the context.
-*/
-static void MD5_Final(unsigned char digest[16], /* message digest */
-                      struct md5_ctx *context) /* context */
+void MD5_Update(MD5_CTX *ctx, const void *data, unsigned long size)
 {
-  unsigned char bits[8];
-  unsigned int count, padLen;
-
-  /* Save number of bits */
-  Encode (bits, context->count, 8);
+	MD5_u32plus saved_lo;
+	unsigned long used, available;
 
-  /* Pad out to 56 mod 64. */
-  count = (unsigned int)((context->count[0] >> 3) & 0x3f);
-  padLen = (count < 56) ? (56 - count) : (120 - count);
-  MD5_Update (context, PADDING, padLen);
+	saved_lo = ctx->lo;
+	if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
+		ctx->hi++;
+	ctx->hi += size >> 29;
 
-  /* Append length (before padding) */
-  MD5_Update (context, bits, 8);
+	used = saved_lo & 0x3f;
 
-  /* Store state in digest */
-  Encode (digest, context->state, 16);
+	if (used) {
+		available = 64 - used;
 
-  /* Zeroize sensitive information. */
-  memset ((void *)context, 0, sizeof (*context));
-}
+		if (size < available) {
+			memcpy(&ctx->buffer[used], data, size);
+			return;
+		}
 
-/* MD5 basic transformation. Transforms state based on block. */
-static void MD5Transform(UINT4 state[4],
-                         const unsigned char block[64])
-{
-  UINT4 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 */
-
- /* 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 */
-
-  /* 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 */
-
-  /* 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 */
-
-  state[0] += a;
-  state[1] += b;
-  state[2] += c;
-  state[3] += d;
-
-  /* Zeroize sensitive information. */
-  memset((void *)x, 0, sizeof (x));
-}
+		memcpy(&ctx->buffer[used], data, available);
+		data = (const unsigned char *)data + available;
+		size -= available;
+		body(ctx, ctx->buffer, 64);
+	}
 
-/* Encodes input (UINT4) into output (unsigned char). Assumes len is
-  a multiple of 4.
- */
-static void Encode (unsigned char *output,
-                    UINT4 *input,
-                    unsigned int len)
-{
-  unsigned int i, j;
+	if (size >= 64) {
+		data = body(ctx, data, size & ~(unsigned long)0x3f);
+		size &= 0x3f;
+	}
 
-  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);
-  }
+	memcpy(ctx->buffer, data, size);
 }
 
-/* Decodes input (unsigned char) into output (UINT4). Assumes len is
-   a multiple of 4.
-*/
-static void Decode (UINT4 *output,
-                    const unsigned char *input,
-                    unsigned int len)
+void MD5_Final(unsigned char *result, MD5_CTX *ctx)
 {
-  unsigned int i, j;
-
-  for(i = 0, j = 0; j < len; i++, j += 4)
-    output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
-      (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
+	unsigned long used, available;
+
+	used = ctx->lo & 0x3f;
+
+	ctx->buffer[used++] = 0x80;
+
+	available = 64 - used;
+
+	if (available < 8) {
+		memset(&ctx->buffer[used], 0, available);
+		body(ctx, ctx->buffer, 64);
+		used = 0;
+		available = 64;
+	}
+
+	memset(&ctx->buffer[used], 0, available - 8);
+
+	ctx->lo <<= 3;
+	ctx->buffer[56] = ctx->lo;
+	ctx->buffer[57] = ctx->lo >> 8;
+	ctx->buffer[58] = ctx->lo >> 16;
+	ctx->buffer[59] = ctx->lo >> 24;
+	ctx->buffer[60] = ctx->hi;
+	ctx->buffer[61] = ctx->hi >> 8;
+	ctx->buffer[62] = ctx->hi >> 16;
+	ctx->buffer[63] = ctx->hi >> 24;
+
+	body(ctx, ctx->buffer, 64);
+
+	result[0] = ctx->a;
+	result[1] = ctx->a >> 8;
+	result[2] = ctx->a >> 16;
+	result[3] = ctx->a >> 24;
+	result[4] = ctx->b;
+	result[5] = ctx->b >> 8;
+	result[6] = ctx->b >> 16;
+	result[7] = ctx->b >> 24;
+	result[8] = ctx->c;
+	result[9] = ctx->c >> 8;
+	result[10] = ctx->c >> 16;
+	result[11] = ctx->c >> 24;
+	result[12] = ctx->d;
+	result[13] = ctx->d >> 8;
+	result[14] = ctx->d >> 16;
+	result[15] = ctx->d >> 24;
+
+	memset(ctx, 0, sizeof(*ctx));
 }
 
 #endif /* CRYPTO LIBS */