changing hmac API + bug fixes

[avr-crypto-lib.git] / hmac-sha1.c

diff --git a/hmac-sha1.c b/hmac-sha1.c
index 9271e50c034b31d3deea4a9011131207d0f4eaaa..56d90acc62a352b3b329dffb1280f58ecaf13abd 100644 (file)
--- a/hmac-sha1.c
+++ b/hmac-sha1.c
@@ -40,7 +40,7 @@
 
 #ifndef HMAC_SHORTONLY
 
-void hmac_sha1_init(hmac_sha1_ctx_t *s, void* key, uint16_t keylength_b){
+void hmac_sha1_init(hmac_sha1_ctx_t *s, const void* key, uint16_t keylength_b){
        uint8_t buffer[SHA1_BLOCK_BYTES];
        uint8_t i;
        
@@ -54,53 +54,46 @@ void hmac_sha1_init(hmac_sha1_ctx_t *s, void* key, uint16_t keylength_b){
        for (i=0; i<SHA1_BLOCK_BYTES; ++i){
                buffer[i] ^= IPAD;
        }
+       sha1_init(&(s->a));
+       sha1_nextBlock(&(s->a), buffer);
+       
+       for (i=0; i<SHA1_BLOCK_BYTES; ++i){
+               buffer[i] ^= IPAD^OPAD;
+       }
+       sha1_init(&(s->b));
+       sha1_nextBlock(&(s->b), buffer);
+       
        
-       sha1_init(s);
-       sha1_nextBlock(s, buffer);
 #if defined SECURE_WIPE_BUFFER
        memset(buffer, 0, SHA1_BLOCK_BYTES);
 #endif
 }
 
-void hmac_sha1_final(hmac_sha1_ctx_t *s, void* key, uint16_t keylength_b){
-       uint8_t buffer[SHA1_BLOCK_BYTES];
-       uint8_t i;
-       sha1_ctx_t a;
-       
-       memset(buffer, 0, SHA1_BLOCK_BYTES);
-       if (keylength_b > SHA1_BLOCK_BITS){
-               sha1((void*)buffer, key, keylength_b);
-       } else {
-               memcpy(buffer, key, (keylength_b+7)/8);
-       }
-       
-       for (i=0; i<SHA1_BLOCK_BYTES; ++i){
-               buffer[i] ^= OPAD;
+void hmac_sha1_nextBlock(hmac_sha1_ctx_t *s, const void* block){
+       sha1_nextBlock(&(s->a), block);
+}
+void hmac_sha1_lastBlock(hmac_sha1_ctx_t *s, const void* block, uint16_t length_b){
+       while(length_b>=SHA1_BLOCK_BITS){
+               sha1_nextBlock(&(s->a), block);
+               block = (uint8_t*)block + SHA1_BLOCK_BYTES;
+               length_b -= SHA1_BLOCK_BITS;
        }
-       
-       sha1_init(&a);
-       sha1_nextBlock(&a, buffer); /* hash key ^ opad */
-       sha1_ctx2hash((void*)buffer, s);  /* copy hash(key ^ ipad, msg) to buffer */
-       sha1_lastBlock(&a, buffer, SHA1_HASH_BITS);
-       memcpy(s, &a, sizeof(sha1_ctx_t));
-#if defined SECURE_WIPE_BUFFER
-       memset(buffer, 0, SHA1_BLOCK_BYTES);
-       memset(&a, 0, sizeof(sha1_ctx_t));
-#endif 
+       sha1_lastBlock(&(s->a), block, length_b);
 }
 
-#endif
+void hmac_sha1_final(void* dest, hmac_sha1_ctx_t *s){
+       sha1_ctx2hash((sha1_hash_t*)dest, &(s->a));
+       sha1_lastBlock(&(s->b), dest, SHA1_HASH_BITS);
+       sha1_ctx2hash((sha1_hash_t*)dest, &(s->b));
+}
 
-/*
-void hmac_sha1_nextBlock()
-void hmac_sha1_lastBlock()
-*/
+#endif
 
 /*
  * keylength in bits!
  * message length in bits!
  */
-void hmac_sha1(void* dest, void* key, uint16_t keylength_b, void* msg, uint32_t msglength_b){ /* a one-shot*/
+void hmac_sha1(void* dest, const void* key, uint16_t keylength_b, const void* msg, uint32_t msglength_b){ /* a one-shot*/
        sha1_ctx_t s;
        uint8_t i;
        uint8_t buffer[SHA1_BLOCK_BYTES];