X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=algos%2Fmd2.c;h=338005c40c05937ad91716d771979f37d9285d46;hb=4fbc2e2a3aa83de683dd440f9036ced5d5879071;hp=9f4099dae3a65b3755666c31f7cbea2276e21e3b;hpb=a5c68f1e55ab389a3472f761664021fe684935f2;p=bertos.git

diff --git a/algos/md2.c b/algos/md2.c
index 9f4099da..338005c4 100755
--- a/algos/md2.c
+++ b/algos/md2.c
@@ -13,6 +13,18 @@
 
 /*#*
  *#* $Log$
+ *#* Revision 1.10  2007/02/02 15:37:45  asterix
+ *#* Change md2_end prototype. Remove a unneeded memcpy in md2_end. Add comments.
+ *#*
+ *#* Revision 1.9  2007/02/02 13:10:01  asterix
+ *#* Fix some bugs in md2_pad and md2_update fuction.
+ *#*
+ *#* Revision 1.8  2007/02/01 14:45:56  asterix
+ *#* Rewrite md2_update function and fix some bug.
+ *#*
+ *#* Revision 1.7  2007/01/31 18:04:15  asterix
+ *#* Write md2_end function
+ *#*
  *#* Revision 1.4  2007/01/31 13:51:57  asterix
  *#* Write md2_compute function.
  *#*
@@ -26,15 +38,17 @@
 
 #include "md2.h"
 
-#include <string.h> //memset();
+#include <string.h>           //memset(), memcpy();
 #include <cfg/compiler.h>
+#include <cfg/debug.h>        //ASSERT()
+#include <cfg/macros.h>       //MIN()
+
 
 /*
  * Official array of 256 byte pemutation contructed from digits of pi, defined
  * in the RFC 1319.
  */
-static uint8_t md2_perm[256] =
-{
+static uint8_t md2_perm[256] = {
   41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
   19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
   76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
@@ -54,65 +68,77 @@ static uint8_t md2_perm[256] =
   166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
   31, 26, 219, 153, 141, 51, 159, 17, 131, 20
 };
+
 /**
- * Pad function. Fill input array with unsigned char until 
- * lenght of block is equal to CONFIG_MD2_BLOCK_LEN.
- *
+ * Pad function. Put len_pad unsigned char in
+ * input block.
  */
-static void md2_pad(void *block, size_t len_pad)
+static void md2_pad(void *_block, size_t len_pad)
 {
-	if (len_pad <= CONFIG_MD2_BLOCK_LEN)
-	{
-		for(int i=(CONFIG_MD2_BLOCK_LEN-len_pad);i<len_pad; i++)
-		{
-			block[i]=(uint8_t)len_pad;
-		}	
-	}
+	uint8_t *block;
+
+	block = (uint8_t *)_block;
+
+	ASSERT(len_pad <= CONFIG_MD2_BLOCK_LEN);
+
+	/*
+	 * Fill input block with len_pad char.
+	 */
+	memset(block, len_pad, len_pad);
+
 }
 
-static void md2_compute(void *state, void *checksum, void *block)
+static void md2_compute(void *_state, void *_checksum, void *_block)
 {
-	int t=0;	
-	uint8_t compute_array[CONFIG_MD2_BLOCK_LEN * 3];
-	
+	int i = 0;
+	uint16_t t = 0;
+	uint8_t compute_array[COMPUTE_ARRAY_LEN];
+	uint8_t *state;
+	uint8_t *checksum;
+	uint8_t *block;
+
+	state = (uint8_t *)_state;
+	checksum  = (uint8_t *)_checksum;
+	block = (uint8_t *)_block;
+
 	/*
- 	 * Copy state and checksum context in compute array. 
- 	 */
+	 * Copy state and checksum context in compute array.
+	 */
 	memcpy(compute_array, state, CONFIG_MD2_BLOCK_LEN);
-	memcpy(compute_array + CONFIG_MD2_BLOCK_LEN, state, CONFIG_MD2_BLOCK_LEN);
-	
+	memcpy(compute_array + CONFIG_MD2_BLOCK_LEN, block, CONFIG_MD2_BLOCK_LEN);
+
 	/*
- 	 * Fill compute array with state XOR block
- 	 */
-	for(int i=0; i< CONFIG_MD2_BLOCK_LEN; i++)
+	 * Fill compute array with state XOR block
+	 */
+	for(i = 0; i < CONFIG_MD2_BLOCK_LEN; i++)
 		compute_array[i + (CONFIG_MD2_BLOCK_LEN * 2)] = state[i] ^ block[i];
-	
+
 	/*
 	 * Encryt block.
 	 */
-	for(i=0; i<NUM_COMPUTE_ROUNDS; i++)
+	for(i = 0; i < NUM_COMPUTE_ROUNDS; i++)
 	{
-		for(int j=0; j<COMPUTE_ARRAY_LEN; j++)
+		for(int j = 0; j < COMPUTE_ARRAY_LEN; j++)
 		{
 			compute_array[j] ^= md2_perm [t];
 			t = compute_array[j];
 		}
-		
+
 		t = (t + i) & 0xff; //modulo 256.
 	}
 	/*
-	 * Update checksum.	
+	 * Update checksum.
 	 */
 	t = checksum[CONFIG_MD2_BLOCK_LEN - 1];
 
-	for(i=0; i< CONFIG_MD2_BLOCK_LEN; i++)
+	for(i = 0; i < CONFIG_MD2_BLOCK_LEN; i++)
 	{
 		checksum[i]  ^= md2_perm [block[i] ^ t];
 		t = checksum[i];
 	}
-	
+
 	/*
-	 * Update state and clean compute array. 
+	 * Update state and clean compute array.
 	 */
 	memcpy(state, compute_array, CONFIG_MD2_BLOCK_LEN);
 	memset(compute_array, 0, sizeof(compute_array));
@@ -125,26 +151,81 @@ static void md2_compute(void *state, void *checksum, void *block)
  */
 void md2_init(Md2Context *context)
 {
-	context->counter=0;
-	memset(context->state, 0, sizeof(context->state));
-	memset(context->checksum, 0, sizeof(context->checksum));
+
+	memset(context, 0, sizeof(Md2Context));
 
 }
+
 /**
- * Update bock.
- *
- *
- *
+ * Update block.
  */
-void md2_update(Md2Context *context, void *block_in, size_t block_len)
+void md2_update(Md2Context *context, void *_block_in, size_t block_len)
 {
 
-}
+	uint8_t *block_in;
+
+	/*
+	 * Choose a number of block that fill input context buffer.
+	 */
+	size_t missing_len = MIN(block_len, CONFIG_MD2_BLOCK_LEN - context->counter);
+
+	block_in = (uint8_t *)_block_in;
+
+	while(block_len > 0)
+	{
+		/*
+		 * Copy in the buffer input block.
+		 */
+		memcpy(&context->buffer[context->counter], block_in, missing_len);
+
+		/*
+		 * Update a context counter, input block length and remaning 
+		 * context buffer block lenght.
+		 */
+		context->counter += missing_len;
+		block_len -= missing_len;
+		block_in += missing_len;
+
+		/*
+		 * If buffer is full, compute it.
+		 */
+		if (context->counter >= CONFIG_MD2_BLOCK_LEN)
+		{
+			md2_compute(context->state, context->checksum, context->buffer);
+			context->counter = 0;
+		}
+	}
 
+
+}
 /**
- * 
+ * Ends an MD2 message digest operation.
+ * This fuction take an context and return a pointer
+ * to context state.
+ *
+ * \param context in input.
+ * \return a pointer to context state (message digest).
  */
-void md2_end(Md2Context *context, void *msg_digest)
+uint8_t  *md2_end(Md2Context *context)
 {
 
+	uint8_t buf[CONFIG_MD2_BLOCK_LEN];
+
+	/*
+	 * Fill remaning empty context buffer.
+	 */
+	md2_pad(buf, CONFIG_MD2_BLOCK_LEN - context->counter);
+
+	/*
+	 * Update context buffer and compute it.
+	 */
+	md2_update(context, buf, CONFIG_MD2_BLOCK_LEN - context->counter);
+
+	/*
+	 * Add context checksum to message input.
+	 */
+	md2_update(context, context->checksum, CONFIG_MD2_BLOCK_LEN);
+
+
+	return context->state; //return a pointer to message digest.
 }