Reorganized to use _nettle_md5_compress, in analogy with

sha1.c.

Rev: src/nettle/md5.c:1.9

diff --git a/md5.c b/md5.c
index 9aecd9a0c1a6949f5e1efb4c63f5737a388f42aa..d398b31e83172f7ad550625a638a6993a0ace091 100644 (file)
--- a/md5.c
+++ b/md5.c
@@ -37,15 +37,6 @@
 
 #include "macros.h"
 
-/* A block, treated as a sequence of 32-bit words. */
-#define MD5_DATA_LENGTH 16
-
-static void
-md5_transform(uint32_t *digest, const uint32_t *data);
-
-static void
-md5_block(struct md5_ctx *ctx, const uint8_t *block);
-
 static void
 md5_final(struct md5_ctx *ctx);
 
@@ -61,6 +52,8 @@ md5_init(struct md5_ctx *ctx)
   ctx->index = 0;
 }
 
+#define MD5_INCR(ctx) ((ctx)->count_h += !++(ctx)->count_l)
+
 void
 md5_update(struct md5_ctx *ctx,
           unsigned length,
@@ -79,14 +72,19 @@ md5_update(struct md5_ctx *ctx,
       else
        {
          memcpy(ctx->block + ctx->index, data, left);
-         md5_block(ctx, ctx->block);
+
+         _nettle_md5_compress(ctx->digest, ctx->block);
+         MD5_INCR(ctx);
+         
          data += left;
          length -= left;
        }
     }
   while (length >= MD5_DATA_SIZE)
     {
-      md5_block(ctx, data);
+      _nettle_md5_compress(ctx->digest, data);
+      MD5_INCR(ctx);
+
       data += MD5_DATA_SIZE;
       length -= MD5_DATA_SIZE;
     }
@@ -130,130 +128,15 @@ md5_digest(struct md5_ctx *ctx,
   md5_init(ctx);
 }
 
-/* MD5 functions */
-#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)))
-
-#define ROUND(f, w, x, y, z, data, s) \
-( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
-
-/* Perform the MD5 transformation on one full block of 16 32-bit
- * words.
- *
- * Compresses 20 (_MD5_DIGEST_LENGTH + MD5_DATA_LENGTH) words into 4
- * (_MD5_DIGEST_LENGTH) words. */
-
-static void
-md5_transform(uint32_t *digest, const uint32_t *data)
-{
-  uint32_t a, b, c, d;
-  a = digest[0];
-  b = digest[1];
-  c = digest[2];
-  d = digest[3];
-
-  ROUND(F1, a, b, c, d, data[ 0] + 0xd76aa478, 7);
-  ROUND(F1, d, a, b, c, data[ 1] + 0xe8c7b756, 12);
-  ROUND(F1, c, d, a, b, data[ 2] + 0x242070db, 17);
-  ROUND(F1, b, c, d, a, data[ 3] + 0xc1bdceee, 22);
-  ROUND(F1, a, b, c, d, data[ 4] + 0xf57c0faf, 7);
-  ROUND(F1, d, a, b, c, data[ 5] + 0x4787c62a, 12);
-  ROUND(F1, c, d, a, b, data[ 6] + 0xa8304613, 17);
-  ROUND(F1, b, c, d, a, data[ 7] + 0xfd469501, 22);
-  ROUND(F1, a, b, c, d, data[ 8] + 0x698098d8, 7);
-  ROUND(F1, d, a, b, c, data[ 9] + 0x8b44f7af, 12);
-  ROUND(F1, c, d, a, b, data[10] + 0xffff5bb1, 17);
-  ROUND(F1, b, c, d, a, data[11] + 0x895cd7be, 22);
-  ROUND(F1, a, b, c, d, data[12] + 0x6b901122, 7);
-  ROUND(F1, d, a, b, c, data[13] + 0xfd987193, 12);
-  ROUND(F1, c, d, a, b, data[14] + 0xa679438e, 17);
-  ROUND(F1, b, c, d, a, data[15] + 0x49b40821, 22);
-
-  ROUND(F2, a, b, c, d, data[ 1] + 0xf61e2562, 5);
-  ROUND(F2, d, a, b, c, data[ 6] + 0xc040b340, 9);
-  ROUND(F2, c, d, a, b, data[11] + 0x265e5a51, 14);
-  ROUND(F2, b, c, d, a, data[ 0] + 0xe9b6c7aa, 20);
-  ROUND(F2, a, b, c, d, data[ 5] + 0xd62f105d, 5);
-  ROUND(F2, d, a, b, c, data[10] + 0x02441453, 9);
-  ROUND(F2, c, d, a, b, data[15] + 0xd8a1e681, 14);
-  ROUND(F2, b, c, d, a, data[ 4] + 0xe7d3fbc8, 20);
-  ROUND(F2, a, b, c, d, data[ 9] + 0x21e1cde6, 5);
-  ROUND(F2, d, a, b, c, data[14] + 0xc33707d6, 9);
-  ROUND(F2, c, d, a, b, data[ 3] + 0xf4d50d87, 14);
-  ROUND(F2, b, c, d, a, data[ 8] + 0x455a14ed, 20);
-  ROUND(F2, a, b, c, d, data[13] + 0xa9e3e905, 5);
-  ROUND(F2, d, a, b, c, data[ 2] + 0xfcefa3f8, 9);
-  ROUND(F2, c, d, a, b, data[ 7] + 0x676f02d9, 14);
-  ROUND(F2, b, c, d, a, data[12] + 0x8d2a4c8a, 20);
-
-  ROUND(F3, a, b, c, d, data[ 5] + 0xfffa3942, 4);
-  ROUND(F3, d, a, b, c, data[ 8] + 0x8771f681, 11);
-  ROUND(F3, c, d, a, b, data[11] + 0x6d9d6122, 16);
-  ROUND(F3, b, c, d, a, data[14] + 0xfde5380c, 23);
-  ROUND(F3, a, b, c, d, data[ 1] + 0xa4beea44, 4);
-  ROUND(F3, d, a, b, c, data[ 4] + 0x4bdecfa9, 11);
-  ROUND(F3, c, d, a, b, data[ 7] + 0xf6bb4b60, 16);
-  ROUND(F3, b, c, d, a, data[10] + 0xbebfbc70, 23);
-  ROUND(F3, a, b, c, d, data[13] + 0x289b7ec6, 4);
-  ROUND(F3, d, a, b, c, data[ 0] + 0xeaa127fa, 11);
-  ROUND(F3, c, d, a, b, data[ 3] + 0xd4ef3085, 16);
-  ROUND(F3, b, c, d, a, data[ 6] + 0x04881d05, 23);
-  ROUND(F3, a, b, c, d, data[ 9] + 0xd9d4d039, 4);
-  ROUND(F3, d, a, b, c, data[12] + 0xe6db99e5, 11);
-  ROUND(F3, c, d, a, b, data[15] + 0x1fa27cf8, 16);
-  ROUND(F3, b, c, d, a, data[ 2] + 0xc4ac5665, 23);
-
-  ROUND(F4, a, b, c, d, data[ 0] + 0xf4292244, 6);
-  ROUND(F4, d, a, b, c, data[ 7] + 0x432aff97, 10);
-  ROUND(F4, c, d, a, b, data[14] + 0xab9423a7, 15);
-  ROUND(F4, b, c, d, a, data[ 5] + 0xfc93a039, 21);
-  ROUND(F4, a, b, c, d, data[12] + 0x655b59c3, 6);
-  ROUND(F4, d, a, b, c, data[ 3] + 0x8f0ccc92, 10);
-  ROUND(F4, c, d, a, b, data[10] + 0xffeff47d, 15);
-  ROUND(F4, b, c, d, a, data[ 1] + 0x85845dd1, 21);
-  ROUND(F4, a, b, c, d, data[ 8] + 0x6fa87e4f, 6);
-  ROUND(F4, d, a, b, c, data[15] + 0xfe2ce6e0, 10);
-  ROUND(F4, c, d, a, b, data[ 6] + 0xa3014314, 15);
-  ROUND(F4, b, c, d, a, data[13] + 0x4e0811a1, 21);
-  ROUND(F4, a, b, c, d, data[ 4] + 0xf7537e82, 6);
-  ROUND(F4, d, a, b, c, data[11] + 0xbd3af235, 10);
-  ROUND(F4, c, d, a, b, data[ 2] + 0x2ad7d2bb, 15);
-  ROUND(F4, b, c, d, a, data[ 9] + 0xeb86d391, 21);
-
-  digest[0] += a;
-  digest[1] += b;
-  digest[2] += c;
-  digest[3] += d;
-}
-
-static void
-md5_block(struct md5_ctx *ctx, const uint8_t *block)
-{
-  uint32_t data[MD5_DATA_LENGTH];
-  unsigned i;
-  
-  /* Update block count */
-  if (!++ctx->count_l)
-    ++ctx->count_h;
-
-  /* Endian independent conversion */
-  for (i = 0; i<16; i++, block += 4)
-    data[i] = LE_READ_UINT32(block);
-
-  md5_transform(ctx->digest, data);
-}
-
 /* Final wrapup - pad to MD5_DATA_SIZE-byte boundary with the bit
  * pattern 1 0* (64-bit count of bits processed, LSB-first) */
 
 static void
 md5_final(struct md5_ctx *ctx)
 {
-  uint32_t data[MD5_DATA_LENGTH];
+  uint32_t bitcount_high;
+  uint32_t bitcount_low;
   unsigned i;
-  unsigned words;
   
   i = ctx->index;
 
@@ -262,32 +145,25 @@ md5_final(struct md5_ctx *ctx)
   assert(i < MD5_DATA_SIZE);
   ctx->block[i++] = 0x80;
 
-  /* Fill rest of word */
-  for( ; i & 3; i++)
-    ctx->block[i] = 0;
-
-  /* i is now a multiple of the word size 4 */
-  words = i >> 2;
-  for (i = 0; i < words; i++)
-    data[i] = LE_READ_UINT32(ctx->block + 4*i);
-  
-  if (words > (MD5_DATA_LENGTH-2))
-    { /* No room for length in this block. Process it and
-       * pad with another one */
-      for (i = words ; i < MD5_DATA_LENGTH; i++)
-       data[i] = 0;
-      md5_transform(ctx->digest, data);
-      for (i = 0; i < (MD5_DATA_LENGTH-2); i++)
-       data[i] = 0;
+  if (i > (MD5_DATA_SIZE - 8))
+    {
+      /* No room for length in this block. Process it and
+        pad with another one */
+      memset(ctx->block + i, 0, MD5_DATA_SIZE - i);
+      
+      _nettle_md5_compress(ctx->digest, ctx->block);
+      i = 0;
     }
-  else
-    for (i = words ; i < MD5_DATA_LENGTH - 2; i++)
-      data[i] = 0;
-  
+  if (i < (MD5_DATA_SIZE - 8))
+    memset(ctx->block + i, 0, (MD5_DATA_SIZE - 8) - i);
+    
   /* There are 512 = 2^9 bits in one block 
    * Little-endian order => Least significant word first */
 
-  data[MD5_DATA_LENGTH-1] = (ctx->count_h << 9) | (ctx->count_l >> 23);
-  data[MD5_DATA_LENGTH-2] = (ctx->count_l << 9) | (ctx->index << 3);
-  md5_transform(ctx->digest, data);
+  bitcount_low = (ctx->count_l << 9) | (ctx->index << 3);
+  bitcount_high = (ctx->count_h << 9) | (ctx->count_l >> 23);
+  LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 8), bitcount_low);
+  LE_WRITE_UINT32(ctx->block + (MD5_DATA_SIZE - 4), bitcount_high);
+  
+  _nettle_md5_compress(ctx->digest, ctx->block);
 }