Implement PSA server-side ECDHE-PSK

Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
This commit is contained in:
Neil Armstrong 2022-03-09 11:38:34 +01:00
parent 868af821c9
commit 039db29c7d

View file

@ -3068,7 +3068,8 @@ curve_matching_done:
#if defined(MBEDTLS_USE_PSA_CRYPTO)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_RSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA )
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA ||
ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{
psa_status_t status = PSA_ERROR_GENERIC_ERROR;
psa_key_attributes_t key_attributes;
@ -4037,6 +4038,96 @@ static int ssl_parse_client_key_exchange( mbedtls_ssl_context *ssl )
}
else
#endif /* MBEDTLS_KEY_EXCHANGE_DHE_PSK_ENABLED */
#if defined(MBEDTLS_USE_PSA_CRYPTO) && \
defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
psa_status_t destruction_status = PSA_ERROR_CORRUPTION_DETECTED;
uint8_t ecpoint_len;
mbedtls_ssl_handshake_params *handshake = ssl->handshake;
if( ( ret = ssl_parse_client_psk_identity( ssl, &p, end ) ) != 0 )
{
MBEDTLS_SSL_DEBUG_RET( 1, ( "ssl_parse_client_psk_identity" ), ret );
psa_destroy_key( handshake->ecdh_psa_privkey );
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
return( ret );
}
/* Keep a copy of the peer's public key */
ecpoint_len = *(p++);
if( (size_t)( end - *p ) < ecpoint_len ) {
psa_destroy_key( handshake->ecdh_psa_privkey );
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
return( MBEDTLS_ERR_SSL_DECODE_ERROR );
}
if( ecpoint_len > sizeof( handshake->ecdh_psa_peerkey ) ) {
psa_destroy_key( handshake->ecdh_psa_privkey );
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
return( MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
}
memcpy( handshake->ecdh_psa_peerkey, p, ecpoint_len );
handshake->ecdh_psa_peerkey_len = ecpoint_len;
p += ecpoint_len;
/* The ECDH secret is the premaster secret used for key derivation. */
unsigned char *psm = ssl->handshake->premaster;
unsigned char *psm_end = psm + sizeof( ssl->handshake->premaster );
size_t zlen;
/* Compute ECDH shared secret. */
status = psa_raw_key_agreement( PSA_ALG_ECDH,
handshake->ecdh_psa_privkey,
handshake->ecdh_psa_peerkey,
handshake->ecdh_psa_peerkey_len,
psm + 2,
psm_end - ( psm + 2 ),
&zlen );
destruction_status = psa_destroy_key( handshake->ecdh_psa_privkey );
handshake->ecdh_psa_privkey = MBEDTLS_SVC_KEY_ID_INIT;
if( status != PSA_SUCCESS || destruction_status != PSA_SUCCESS )
return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
MBEDTLS_PUT_UINT16_BE( zlen, psm, 0 );
psm += 2 + zlen;
/* opaque psk<0..2^16-1>; */
if( psm_end - psm < 2 )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
const unsigned char *psk = NULL;
size_t psk_len = 0;
if( mbedtls_ssl_get_psk( ssl, &psk, &psk_len )
== MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED )
{
/*
* This should never happen because the existence of a PSK is always
* checked before calling this function
*/
return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
}
MBEDTLS_PUT_UINT16_BE( psk_len, psm, 0 );
psm += 2;
if( psm_end < psm || (size_t)( psm_end - psm ) < psk_len )
return( MBEDTLS_ERR_SSL_BAD_INPUT_DATA );
memcpy( psm, psk, psk_len );
psm += psk_len;
ssl->handshake->pmslen = psm - ssl->handshake->premaster;
}
else
#endif /* MBEDTLS_USE_PSA_CRYPTO &&
MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED */
#if defined(MBEDTLS_KEY_EXCHANGE_ECDHE_PSK_ENABLED)
if( ciphersuite_info->key_exchange == MBEDTLS_KEY_EXCHANGE_ECDHE_PSK )
{