void hb_hmac_sha256_init(hmac_sha256_ctx *ctx, const void *keyv,
unsigned int key_size)
{
unsigned int fill;
unsigned int num;
const unsigned char *key = ( const unsigned char * ) keyv;
const unsigned char *key_used;
unsigned char key_temp[SHA256_DIGEST_SIZE];
unsigned int i;
if (key_size == SHA256_BLOCK_SIZE) {
key_used = key;
num = SHA256_BLOCK_SIZE;
} else {
if (key_size > SHA256_BLOCK_SIZE){
hb_sha256(key, key_size, key_temp);
key_used = key_temp;
num = SHA256_DIGEST_SIZE;
} else { /* key_size > SHA256_BLOCK_SIZE */
key_used = key;
num = key_size;
}
fill = SHA256_BLOCK_SIZE - num;
memset(ctx->block_ipad + num, 0x36, fill);
memset(ctx->block_opad + num, 0x5c, fill);
}
for (i = 0; i < num; i++) {
ctx->block_ipad[i] = key_used[i] ^ 0x36;
ctx->block_opad[i] = key_used[i] ^ 0x5c;
}
hb_sha256_init(&ctx->ctx_inside);
hb_sha256_update(&ctx->ctx_inside, ctx->block_ipad, SHA256_BLOCK_SIZE);
hb_sha256_init(&ctx->ctx_outside);
hb_sha256_update(&ctx->ctx_outside, ctx->block_opad,
SHA256_BLOCK_SIZE);
/* for hmac_reinit */
memcpy(&ctx->ctx_inside_reinit, &ctx->ctx_inside,
sizeof(sha256_ctx));
memcpy(&ctx->ctx_outside_reinit, &ctx->ctx_outside,
sizeof(sha256_ctx));
}
void hb_sha256( const void * message, unsigned int len, unsigned char * digest )
{
sha256_ctx ctx;
hb_sha256_init( &ctx );
hb_sha256_update( &ctx, message, len );
hb_sha256_final( &ctx, digest );
}
void hb_hmac_sha256_final(hmac_sha256_ctx *ctx, unsigned char *mac,
unsigned int mac_size)
{
unsigned char digest_inside[SHA256_DIGEST_SIZE];
unsigned char mac_temp[SHA256_DIGEST_SIZE];
hb_sha256_final(&ctx->ctx_inside, digest_inside);
hb_sha256_update(&ctx->ctx_outside, digest_inside, SHA256_DIGEST_SIZE);
hb_sha256_final(&ctx->ctx_outside, mac_temp);
memcpy(mac, mac_temp, mac_size);
}
void hb_hmac_sha256_update(hmac_sha256_ctx *ctx, const void *message,
unsigned int message_len)
{
hb_sha256_update(&ctx->ctx_inside, message, message_len);
}
