evp/e_aes_cbc_hmac_{sha1|sha256}.c: tag reference code.

Reviewed-by: Richard Levitte <levitte@openssl.org>

crypto/evp/e_aes_cbc_hmac_sha1.c

@@ -565,7 +565,7 @@ static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
             }
 # endif
 
-# if 1
+# if 1      /* see original reference version in #else */
             len -= SHA_DIGEST_LENGTH; /* amend mac */
             if (len >= (256 + SHA_CBLOCK)) {
                 j = (len - (256 + SHA_CBLOCK)) & (0 - SHA_CBLOCK);
@@ -659,7 +659,7 @@ static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
             }
 #  endif
             len += SHA_DIGEST_LENGTH;
-# else
+# else      /* pre-lucky-13 reference version of above */
             SHA1_Update(&key->md, out, inp_len);
             res = key->md.num;
             SHA1_Final(pmac->c, &key->md);
@@ -686,7 +686,7 @@ static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
             /* verify HMAC */
             out += inp_len;
             len -= inp_len;
-# if 1
+# if 1      /* see original reference version in #else */
             {
                 unsigned char *p = out + len - 1 - maxpad - SHA_DIGEST_LENGTH;
                 size_t off = out - p;
@@ -708,7 +708,7 @@ static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out,
                 res = 0 - ((0 - res) >> (sizeof(res) * 8 - 1));
                 ret &= (int)~res;
             }
-# else
+# else      /* pre-lucky-13 reference version of above */
             for (res = 0, i = 0; i < SHA_DIGEST_LENGTH; i++)
                 res |= out[i] ^ pmac->c[i];
             res = 0 - ((0 - res) >> (sizeof(res) * 8 - 1));

crypto/evp/e_aes_cbc_hmac_sha256.c

@@ -552,7 +552,7 @@ static int aesni_cbc_hmac_sha256_cipher(EVP_CIPHER_CTX *ctx,
             key->md = key->head;
             SHA256_Update(&key->md, key->aux.tls_aad, plen);
 
-# if 1
+# if 1      /* see original reference version in #else */
             len -= SHA256_DIGEST_LENGTH; /* amend mac */
             if (len >= (256 + SHA256_CBLOCK)) {
                 j = (len - (256 + SHA256_CBLOCK)) & (0 - SHA256_CBLOCK);
@@ -680,7 +680,7 @@ static int aesni_cbc_hmac_sha256_cipher(EVP_CIPHER_CTX *ctx,
                 for (; inp_blocks < pad_blocks; inp_blocks++)
                     sha1_block_data_order(&key->md, data, 1);
             }
-# endif
+# endif      /* pre-lucky-13 reference version of above */
             key->md = key->tail;
             SHA256_Update(&key->md, pmac->c, SHA256_DIGEST_LENGTH);
             SHA256_Final(pmac->c, &key->md);
@@ -688,7 +688,7 @@ static int aesni_cbc_hmac_sha256_cipher(EVP_CIPHER_CTX *ctx,
             /* verify HMAC */
             out += inp_len;
             len -= inp_len;
-# if 1
+# if 1      /* see original reference version in #else */
             {
                 unsigned char *p =
                     out + len - 1 - maxpad - SHA256_DIGEST_LENGTH;
@@ -711,7 +711,7 @@ static int aesni_cbc_hmac_sha256_cipher(EVP_CIPHER_CTX *ctx,
                 res = 0 - ((0 - res) >> (sizeof(res) * 8 - 1));
                 ret &= (int)~res;
             }
-# else
+# else      /* pre-lucky-13 reference version of above */
             for (res = 0, i = 0; i < SHA256_DIGEST_LENGTH; i++)
                 res |= out[i] ^ pmac->c[i];
             res = 0 - ((0 - res) >> (sizeof(res) * 8 - 1));