Add support for truncated MAC algorithms

This commit is contained in:
Gilles Peskine 2018-08-14 15:18:45 +02:00
parent a7aa442c7c
commit d911eb7915
4 changed files with 168 additions and 9 deletions

View File

@ -756,6 +756,56 @@ typedef uint32_t psa_algorithm_t;
(((alg) & (PSA_ALG_CATEGORY_MASK | PSA_ALG_MAC_SUBCATEGORY_MASK)) == \
PSA_ALG_HMAC_BASE)
#define PSA_ALG_MAC_TRUNCATION_MASK ((psa_algorithm_t)0x00003f00)
#define PSA_MAC_TRUNCATION_OFFSET 8
/** Macro to build a truncated MAC algorithm.
*
* A truncated MAC algorithm is identical to the corresponding MAC
* algorithm except that the MAC value for the truncated algorithm
* consists of only the first \p mac_length bytes of the MAC value
* for the untruncated algorithm.
*
* \note This macro may allow constructing algorithm identifiers that
* are not valid, either because the specified length is larger
* than the untruncated MAC or because the specified length is
* smaller than permitted by the implementation.
*
* \note It is implementation-defined whether a truncated MAC that
* is truncated to the same length as the MAC of the untruncated
* algorithm is considered identical to the untruncated algorithm
* for policy comparison purposes.
*
* \param alg A MAC algorithm identifier (value of type
* #psa_algorithm_t such that #PSA_ALG_IS_MAC(\p alg)
* is true). This may be a truncated or untruncated
* MAC algorithm.
* \param mac_length Desired length of the truncated MAC in bytes.
*
* \return The corresponding MAC algorithm with the specified
* length.
* \return Unspecified if \p alg is not a supported
* MAC algorithm or if \p mac_length is too small or
* too large for the specified MAC algorithm.
*/
#define PSA_ALG_TRUNCATED_MAC(alg, mac_length) \
(((alg) & ~PSA_ALG_MAC_TRUNCATION_MASK) | \
((mac_length) << PSA_MAC_TRUNCATION_OFFSET & PSA_ALG_MAC_TRUNCATION_MASK))
/** Length to which a MAC algorithm is truncated.
*
* \param alg A MAC algorithm identifier (value of type
* #psa_algorithm_t such that #PSA_ALG_IS_MAC(\p alg)
* is true).
*
* \return Length of the truncated MAC in bytes.
* \return 0 if \p alg is a non-truncated MAC algorithm.
* \return Unspecified if \p alg is not a supported
* MAC algorithm.
*/
#define PSA_MAC_TRUNCATED_LENGTH(alg) \
(((alg) & PSA_ALG_MAC_TRUNCATION_MASK) >> PSA_MAC_TRUNCATION_OFFSET)
#define PSA_ALG_CIPHER_MAC_BASE ((psa_algorithm_t)0x02c00000)
#define PSA_ALG_CBC_MAC ((psa_algorithm_t)0x02c00001)
#define PSA_ALG_CMAC ((psa_algorithm_t)0x02c00002)

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@ -143,7 +143,8 @@
PSA_VENDOR_ECC_MAX_CURVE_BITS \
)
/** The maximum size of a block cipher supported by the implementation. */
#define PSA_MAX_BLOCK_CIPHER_BLOCK_SIZE 16
/** The size of the output of psa_mac_sign_finish(), in bytes.
*
@ -163,7 +164,8 @@
* with the algorithm.
*/
#define PSA_MAC_FINAL_SIZE(key_type, key_bits, alg) \
(PSA_ALG_IS_HMAC(alg) ? PSA_HASH_SIZE(PSA_ALG_HMAC_GET_HASH(alg)) : \
((alg) & PSA_ALG_MAC_TRUNCATION_MASK ? PSA_MAC_TRUNCATED_LENGTH(alg) : \
PSA_ALG_IS_HMAC(alg) ? PSA_HASH_SIZE(PSA_ALG_HMAC_GET_HASH(alg)) : \
PSA_ALG_IS_BLOCK_CIPHER_MAC(alg) ? PSA_BLOCK_CIPHER_BLOCK_SIZE(key_type) : \
((void)(key_type), (void)(key_bits), 0))

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@ -1523,8 +1523,10 @@ static psa_status_t psa_mac_setup( psa_mac_operation_t *operation,
size_t key_bits;
psa_key_usage_t usage =
is_sign ? PSA_KEY_USAGE_SIGN : PSA_KEY_USAGE_VERIFY;
unsigned char truncated = PSA_MAC_TRUNCATED_LENGTH( alg );
psa_algorithm_t full_length_alg = alg & ~PSA_ALG_MAC_TRUNCATION_MASK;
status = psa_mac_init( operation, alg );
status = psa_mac_init( operation, full_length_alg );
if( status != PSA_SUCCESS )
return( status );
if( is_sign )
@ -1536,10 +1538,11 @@ static psa_status_t psa_mac_setup( psa_mac_operation_t *operation,
key_bits = psa_get_key_bits( slot );
#if defined(MBEDTLS_CMAC_C)
if( alg == PSA_ALG_CMAC )
if( full_length_alg == PSA_ALG_CMAC )
{
const mbedtls_cipher_info_t *cipher_info =
mbedtls_cipher_info_from_psa( alg, slot->type, key_bits, NULL );
mbedtls_cipher_info_from_psa( full_length_alg,
slot->type, key_bits, NULL );
int ret;
if( cipher_info == NULL )
{
@ -1553,7 +1556,7 @@ static psa_status_t psa_mac_setup( psa_mac_operation_t *operation,
else
#endif /* MBEDTLS_CMAC_C */
#if defined(MBEDTLS_MD_C)
if( PSA_ALG_IS_HMAC( alg ) )
if( PSA_ALG_IS_HMAC( full_length_alg ) )
{
psa_algorithm_t hash_alg = PSA_ALG_HMAC_GET_HASH( alg );
if( hash_alg == 0 )
@ -1588,6 +1591,24 @@ static psa_status_t psa_mac_setup( psa_mac_operation_t *operation,
status = PSA_ERROR_NOT_SUPPORTED;
}
if( truncated == 0 )
{
/* The "normal" case: untruncated algorithm. Nothing to do. */
}
else if( truncated < 4 )
{
/* Too small to make any sense. Reject. 4 bytes is too small for
* security but ancient protocols with 32-bit MACs do exist. */
status = PSA_ERROR_NOT_SUPPORTED;
}
else if( truncated > operation->mac_size )
{
/* It's impossible to "truncate" to a larger length. */
status = PSA_ERROR_INVALID_ARGUMENT;
}
else
operation->mac_size = truncated;
exit:
if( status != PSA_SUCCESS )
{
@ -1682,7 +1703,11 @@ static psa_status_t psa_hmac_finish_internal( psa_hmac_internal_data *hmac,
if( status != PSA_SUCCESS )
goto exit;
status = psa_hash_finish( &hmac->hash_ctx, mac, mac_size, &hash_size );
status = psa_hash_finish( &hmac->hash_ctx, tmp, sizeof( tmp ), &hash_size );
if( status != PSA_SUCCESS )
goto exit;
memcpy( mac, tmp, mac_size );
exit:
mbedtls_zeroize( tmp, hash_size );
@ -1705,7 +1730,11 @@ static psa_status_t psa_mac_finish_internal( psa_mac_operation_t *operation,
#if defined(MBEDTLS_CMAC_C)
if( operation->alg == PSA_ALG_CMAC )
{
int ret = mbedtls_cipher_cmac_finish( &operation->ctx.cmac, mac );
uint8_t tmp[PSA_MAX_BLOCK_CIPHER_BLOCK_SIZE];
int ret = mbedtls_cipher_cmac_finish( &operation->ctx.cmac, tmp );
if( ret == 0 )
memcpy( mac, tmp, mac_size );
mbedtls_zeroize( tmp, sizeof( tmp ) );
return( mbedtls_to_psa_error( ret ) );
}
else
@ -1714,7 +1743,7 @@ static psa_status_t psa_mac_finish_internal( psa_mac_operation_t *operation,
if( PSA_ALG_IS_HMAC( operation->alg ) )
{
return( psa_hmac_finish_internal( &operation->ctx.hmac,
mac, mac_size ) );
mac, operation->mac_size ) );
}
else
#endif /* MBEDTLS_MD_C */
@ -1793,6 +1822,8 @@ cleanup:
else
psa_mac_abort( operation );
mbedtls_zeroize( actual_mac, mac_length );
return( status );
}

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@ -466,10 +466,86 @@ PSA MAC verify: RFC4231 Test case 7 - HMAC-SHA-512
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_verify:PSA_KEY_TYPE_HMAC:"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa":PSA_ALG_HMAC(PSA_ALG_SHA_512):"5468697320697320612074657374207573696e672061206c6172676572207468616e20626c6f636b2d73697a65206b657920616e642061206c6172676572207468616e20626c6f636b2d73697a6520646174612e20546865206b6579206e6565647320746f20626520686173686564206265666f7265206265696e6720757365642062792074686520484d414320616c676f726974686d2e":"e37b6a775dc87dbaa4dfa9f96e5e3ffddebd71f8867289865df5a32d20cdc944b6022cac3c4982b10d5eeb55c3e4de15134676fb6de0446065c97440fa8c6a58"
PSA MAC sign: HMAC-SHA-224, truncated to 28 bytes (actual size)
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA256_C
mac_sign:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_224), 28):"4869205468657265":"896fb1128abbdf196832107cd49df33f47b4b1169912ba4f53684b22"
PSA MAC verify: HMAC-SHA-224, truncated to 28 bytes (actual size)
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA256_C
mac_verify:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_224), 28):"4869205468657265":"896fb1128abbdf196832107cd49df33f47b4b1169912ba4f53684b22"
PSA MAC sign: HMAC-SHA-512, truncated to 64 bytes (actual size)
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_sign:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_512), 64):"4869205468657265":"87aa7cdea5ef619d4ff0b4241a1d6cb02379f4e2ce4ec2787ad0b30545e17cdedaa833b7d6b8a702038b274eaea3f4e4be9d914eeb61f1702e696c203a126854"
PSA MAC verify: HMAC-SHA-512, truncated to 64 bytes (actual size)
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_verify:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_512), 64):"4869205468657265":"87aa7cdea5ef619d4ff0b4241a1d6cb02379f4e2ce4ec2787ad0b30545e17cdedaa833b7d6b8a702038b274eaea3f4e4be9d914eeb61f1702e696c203a126854"
PSA MAC sign: HMAC-SHA-224, truncated to 27 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA256_C
mac_sign:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_224), 27):"4869205468657265":"896fb1128abbdf196832107cd49df33f47b4b1169912ba4f53684b"
PSA MAC verify: HMAC-SHA-224, truncated to 27 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA256_C
mac_verify:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_224), 27):"4869205468657265":"896fb1128abbdf196832107cd49df33f47b4b1169912ba4f53684b"
PSA MAC sign: HMAC-SHA-512, truncated to 63 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_sign:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_512), 63):"4869205468657265":"87aa7cdea5ef619d4ff0b4241a1d6cb02379f4e2ce4ec2787ad0b30545e17cdedaa833b7d6b8a702038b274eaea3f4e4be9d914eeb61f1702e696c203a1268"
PSA MAC verify: HMAC-SHA-512, truncated to 63 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_verify:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_512), 63):"4869205468657265":"87aa7cdea5ef619d4ff0b4241a1d6cb02379f4e2ce4ec2787ad0b30545e17cdedaa833b7d6b8a702038b274eaea3f4e4be9d914eeb61f1702e696c203a1268"
PSA MAC sign: HMAC-SHA-224, truncated to 4 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA256_C
mac_sign:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_224), 4):"4869205468657265":"896fb112"
PSA MAC verify: HMAC-SHA-224, truncated to 4 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA256_C
mac_verify:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_224), 4):"4869205468657265":"896fb112"
PSA MAC sign: HMAC-SHA-512, truncated to 4 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_sign:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_512), 4):"4869205468657265":"87aa7cde"
PSA MAC verify: HMAC-SHA-512, truncated to 4 bytes
depends_on:MBEDTLS_MD_C:MBEDTLS_SHA512_C
mac_verify:PSA_KEY_TYPE_HMAC:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_ALG_TRUNCATED_MAC(PSA_ALG_HMAC(PSA_ALG_SHA_512), 4):"4869205468657265":"87aa7cde"
PSA MAC sign: CMAC-AES-128
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_sign:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_CMAC:"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747de9ae63030ca32611497c827"
PSA MAC verify: CMAC-AES-128
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_verify:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_CMAC:"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747de9ae63030ca32611497c827"
PSA MAC sign: CMAC-AES-128, truncated to 16 bytes (actual size)
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_sign:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_TRUNCATED_MAC(PSA_ALG_CMAC, 16):"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747de9ae63030ca32611497c827"
PSA MAC verify: CMAC-AES-128, truncated to 16 bytes (actual size)
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_verify:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_TRUNCATED_MAC(PSA_ALG_CMAC, 16):"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747de9ae63030ca32611497c827"
PSA MAC sign: CMAC-AES-128, truncated to 15 bytes
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_sign:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_TRUNCATED_MAC(PSA_ALG_CMAC, 15):"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747de9ae63030ca32611497c8"
PSA MAC verify: CMAC-AES-128, truncated to 15 bytes
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_verify:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_TRUNCATED_MAC(PSA_ALG_CMAC, 15):"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747de9ae63030ca32611497c8"
PSA MAC sign: CMAC-AES-128, truncated to 4 bytes
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_sign:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_TRUNCATED_MAC(PSA_ALG_CMAC, 4):"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747"
PSA MAC verify: CMAC-AES-128, truncated to 4 bytes
depends_on:MBEDTLS_CMAC_C:MBEDTLS_AES_C
mac_verify:PSA_KEY_TYPE_AES:"2b7e151628aed2a6abf7158809cf4f3c":PSA_ALG_TRUNCATED_MAC(PSA_ALG_CMAC, 4):"6bc1bee22e409f96e93d7e117393172aae2d8a571e03ac9c9eb76fac45af8e5130c81c46a35ce411":"dfa66747"
PSA cipher setup: good, AES-CTR
depends_on:MBEDTLS_AES_C:MBEDTLS_CIPHER_MODE_CTR
cipher_setup:PSA_KEY_TYPE_AES:"000102030405060708090a0b0c0d0e0f":PSA_ALG_CTR:PSA_SUCCESS