TLS 1.3: Add pre-shared-key multiple psk parser
Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 381f0c4..ecc2a62 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -680,6 +680,7 @@
unsigned char *psk; /*!< PSK from the callback */
size_t psk_len; /*!< Length of PSK from callback */
#endif /* MBEDTLS_USE_PSA_CRYPTO */
+ uint16_t selected_identity;
#endif /* MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED */
#if defined(MBEDTLS_SSL_ECP_RESTARTABLE_ENABLED)
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index d095fca..d67f453 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -119,6 +119,7 @@
return( SSL_TLS1_3_OFFERED_PSK_NOT_MATCH );
}
+ MBEDTLS_SSL_DEBUG_BUF( 5, "identity", identity, identity_len );
/* Check identity with pre-configured psk */
if( identity_len == ssl->conf->psk_identity_len &&
mbedtls_ct_memcmp( ssl->conf->psk_identity,
@@ -132,20 +133,59 @@
}
MBEDTLS_CHECK_RETURN_CRITICAL
-static int ssl_tls13_offered_psks_check_binder_match(
- mbedtls_ssl_context *ssl,
- const unsigned char *binder,
- uint16_t binder_len,
- const unsigned char *psk,
- size_t psk_len )
+static int ssl_tls13_get_psk( mbedtls_ssl_context *ssl,
+ const unsigned char **psk,
+ size_t *psk_len )
+{
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+ psa_key_attributes_t key_attributes = PSA_KEY_ATTRIBUTES_INIT;
+ psa_status_t status;
+
+ *psk_len = 0;
+ *psk = NULL;
+
+ status = psa_get_key_attributes( ssl->handshake->psk_opaque, &key_attributes );
+ if( status != PSA_SUCCESS)
+ {
+ return( psa_ssl_status_to_mbedtls( status ) );
+ }
+
+ *psk_len = PSA_BITS_TO_BYTES(psa_get_key_bits( &key_attributes ) );
+ *psk = mbedtls_calloc( 1, *psk_len );
+ if( *psk == NULL )
+ {
+ return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
+ }
+
+ status = psa_export_key( ssl->handshake->psk_opaque,
+ (uint8_t *)*psk, *psk_len, psk_len );
+ if( status != PSA_SUCCESS)
+ {
+ mbedtls_free( (void *)*psk );
+ return( psa_ssl_status_to_mbedtls( status ) );
+ }
+#else
+ *psk = ssl->handshake->psk;
+ *psk_len = ssl->handshake->psk_len;
+#endif /* !MBEDTLS_USE_PSA_CRYPTO */
+ return( 0 );
+}
+
+MBEDTLS_CHECK_RETURN_CRITICAL
+static int ssl_tls13_offered_psks_check_binder_match( mbedtls_ssl_context *ssl,
+ const unsigned char *binder,
+ uint16_t binder_len )
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
int psk_type;
+
mbedtls_md_type_t md_alg =
binder_len == 32 ? MBEDTLS_MD_SHA256 : MBEDTLS_MD_SHA384 ;
psa_algorithm_t psa_md_alg = mbedtls_psa_translate_md( md_alg );
unsigned char transcript[PSA_HASH_MAX_SIZE];
size_t transcript_len;
+ const unsigned char *psk;
+ size_t psk_len;
unsigned char server_computed_binder[PSA_HASH_MAX_SIZE];
psk_type = MBEDTLS_SSL_TLS1_3_PSK_EXTERNAL;
@@ -157,11 +197,17 @@
if( ret != 0 )
return( ret );
+ ret = ssl_tls13_get_psk( ssl, &psk, &psk_len );
+ if( ret != 0 )
+ return( ret );
+
ret = mbedtls_ssl_tls13_create_psk_binder( ssl, psa_md_alg,
psk, psk_len, psk_type,
transcript,
server_computed_binder );
- /* We do not check for multiple binders */
+#if defined(MBEDTLS_USE_PSA_CRYPTO)
+ mbedtls_free( (void*)psk );
+#endif
if( ret != 0 )
{
MBEDTLS_SSL_DEBUG_MSG( 1, ( "PSK binder calculation failed." ) );
@@ -181,6 +227,7 @@
sizeof( server_computed_binder ) );
return( SSL_TLS1_3_OFFERED_PSK_NOT_MATCH );
}
+
/* Parser for pre_shared_key extension in client hello
* struct {
* opaque identity<1..2^16-1>;
@@ -206,63 +253,89 @@
const unsigned char *buf,
const unsigned char *end )
{
- int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- const unsigned char *p = buf;
+ const unsigned char *next_identity = buf;
uint16_t identities_len;
const unsigned char *identities_end;
- uint32_t identity_matched = SSL_TLS1_3_OFFERED_PSK_NOT_MATCH;
+ const unsigned char *next_binder;
uint16_t binders_len;
const unsigned char *binders_end;
- unsigned char *psk = NULL;
- size_t psk_len = 0;
- int binder_matched = 0;
-#if defined(MBEDTLS_USE_PSA_CRYPTO)
- psa_key_attributes_t key_attributes = PSA_KEY_ATTRIBUTES_INIT;
- psa_status_t status;
-#endif /* MBEDTLS_USE_PSA_CRYPTO */
+ int matched_identity = -1;
+ int identity_id = -1;
MBEDTLS_SSL_DEBUG_BUF( 3, "pre_shared_key extesion", buf, end - buf );
- /* identities >= 7 bytes */
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 7 );
+ /* identities_len 2 bytes
+ * identities_data >= 7 bytes
+ */
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_identity, end, 7 + 2 );
+ identities_len = MBEDTLS_GET_UINT16_BE( next_identity, 0 );
+ next_identity += 2;
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_identity, end, identities_len );
+ identities_end = next_identity + identities_len;
- identities_len = MBEDTLS_GET_UINT16_BE( p, 0 );
- p += 2;
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, identities_len );
- identities_end = p + identities_len;
+ /* binders_len 2 bytes
+ * binders >= 33 bytes
+ */
+ next_binder = identities_end;
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_binder, end, 33 );
+ binders_len = MBEDTLS_GET_UINT16_BE( next_binder, 0 );
+ next_binder += 2;
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_binder, end, binders_len );
+ binders_end = next_binder + binders_len;
- while( p < identities_end )
+ ssl->handshake->update_checksum( ssl, buf, identities_end - buf );
+
+ while( next_identity < identities_end && next_binder < binders_end )
{
- uint16_t identity_len;
const unsigned char *identity;
+ uint16_t identity_len;
+ const unsigned char *binder;
+ uint16_t binder_len;
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, identities_end, 2 );
- identity_len = MBEDTLS_GET_UINT16_BE( p, 0 );
- p += 2;
- identity = p;
- MBEDTLS_SSL_CHK_BUF_READ_PTR( identity,
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_identity, identities_end, 2 );
+ identity_len = MBEDTLS_GET_UINT16_BE( next_identity, 0 );
+ next_identity += 2;
+ identity = next_identity;
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_identity,
identities_end,
identity_len + 4 );
- p += identity_len + 4;
+ next_identity += identity_len + 4;
- if( identity_matched == SSL_TLS1_3_OFFERED_PSK_MATCH )
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_binder, binders_end, 2 );
+
+ binder_len = *next_binder++;
+ binder = next_binder;
+ MBEDTLS_SSL_CHK_BUF_READ_PTR( next_binder, binders_end, binder_len );
+ next_binder += binder_len;
+
+ identity_id++;
+ if( matched_identity != -1 )
continue;
- MBEDTLS_SSL_DEBUG_BUF( 3, "received psk identity",
- identity, identity_len );
- identity_matched = ssl_tls13_offered_psks_check_identity_match(
- ssl, identity, identity_len );
+ ret = ssl_tls13_offered_psks_check_identity_match(
+ ssl, identity, identity_len );
+ if( SSL_TLS1_3_OFFERED_PSK_NOT_MATCH == ret )
+ continue;
+
+ ret = ssl_tls13_offered_psks_check_binder_match(
+ ssl, binder, binder_len );
+ if( ret < 0 )
+ {
+ MBEDTLS_SSL_DEBUG_RET( 1,
+ "ssl_tls13_offered_psks_check_binder_match" , ret );
+ MBEDTLS_SSL_PEND_FATAL_ALERT(
+ MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR,
+ MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
+ return( ret );
+ }
+ if( SSL_TLS1_3_OFFERED_PSK_NOT_MATCH == ret )
+ continue;
+
+ matched_identity = identity_id;
}
- if( identity_matched != SSL_TLS1_3_OFFERED_PSK_MATCH )
- {
- MBEDTLS_SSL_PEND_FATAL_ALERT(
- MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY,
- MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY );
- return( MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY );
- }
-
- if( p != identities_end )
+ if( next_identity != identities_end || next_binder != binders_end )
{
MBEDTLS_SSL_DEBUG_MSG( 3, ( "pre_shared_key extesion decode error" ) );
MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR,
@@ -270,99 +343,23 @@
return( MBEDTLS_ERR_SSL_DECODE_ERROR );
}
- ssl->handshake->update_checksum( ssl, buf, p - buf );
-
- /* binders >= 33 bytes */
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 33 );
- binders_len = MBEDTLS_GET_UINT16_BE( p, 0 );
- p += 2;
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, binders_len );
- binders_end = p + binders_len;
-
-#if defined(MBEDTLS_USE_PSA_CRYPTO)
- status = psa_get_key_attributes( ssl->handshake->psk_opaque,
- &key_attributes );
- if( status != PSA_SUCCESS)
+ if( matched_identity == -1 )
{
- return( psa_ssl_status_to_mbedtls( status ) );
- }
-
- psk_len = PSA_BITS_TO_BYTES(psa_get_key_bits( &key_attributes ) );
- psk = mbedtls_calloc( 1, psk_len );
- if( psk == NULL )
- {
- return( MBEDTLS_ERR_SSL_ALLOC_FAILED );
- }
- status = psa_export_key(ssl->handshake->psk_opaque, psk, psk_len, &psk_len );
- if( status != PSA_SUCCESS)
- {
- ret = psa_ssl_status_to_mbedtls( status );
- goto exit_failure;
- }
-#else
- psk = ssl->handshake->psk;
- psk_len = ssl->handshake->psk_len;
-#endif /* !MBEDTLS_USE_PSA_CRYPTO */
-
- while( p < binders_end )
- {
- uint8_t binder_len;
- const unsigned char *binder;
-
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, binders_end, 1 );
- binder_len = *p++;
- MBEDTLS_SSL_CHK_BUF_READ_PTR( p, binders_end, binder_len );
- binder = p;
- p += binder_len;
-
- if( binder_matched == SSL_TLS1_3_OFFERED_PSK_MATCH)
- continue;
-
- binder_matched = ssl_tls13_offered_psks_check_binder_match(
- ssl, binder, binder_len, psk, psk_len );
- if( binder_matched < 0 )
- {
- MBEDTLS_SSL_DEBUG_RET( 1,
- "ssl_tls13_offered_psks_check_binder_match" , binder_matched );
- MBEDTLS_SSL_PEND_FATAL_ALERT(
- MBEDTLS_SSL_ALERT_MSG_DECRYPT_ERROR,
- MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
- ret = binder_matched;
- goto exit_failure;
- }
- }
-
- if( binder_matched != SSL_TLS1_3_OFFERED_PSK_MATCH )
- {
- MBEDTLS_SSL_DEBUG_MSG( 1,
- ( "Received psk binder does not match computed psk binder." ) );
+ MBEDTLS_SSL_DEBUG_MSG( 3, ( "No matched pre shared key found" ) );
MBEDTLS_SSL_PEND_FATAL_ALERT(
- MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE,
- MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE );
- ret = MBEDTLS_ERR_SSL_HANDSHAKE_FAILURE;
- goto exit_failure;
+ MBEDTLS_SSL_ALERT_MSG_UNKNOWN_PSK_IDENTITY,
+ MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY );
+ return( MBEDTLS_ERR_SSL_UNKNOWN_IDENTITY );
}
- if( p != binders_end )
- {
- MBEDTLS_SSL_DEBUG_MSG( 3, ( "pre_shared_key extesion decode error" ) );
- MBEDTLS_SSL_PEND_FATAL_ALERT( MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR,
- MBEDTLS_ERR_SSL_DECODE_ERROR );
- ret = MBEDTLS_ERR_SSL_DECODE_ERROR;
- goto exit_failure;
- }
+ ssl->handshake->selected_identity = (uint16_t)matched_identity;
+ MBEDTLS_SSL_DEBUG_MSG( 3, ( "Pre shared key found" ) );
/* Update the handshake transcript with the binder list. */
ssl->handshake->update_checksum( ssl,
identities_end,
- (size_t)( p - identities_end ) );
- ret = 0;
-
-exit_failure:
-#if defined(MBEDTLS_USE_PSA_CRYPTO)
- mbedtls_free( (void *)psk );
-#endif
- return( ret );
+ (size_t)( binders_end - identities_end ) );
+ return( 0 );
}
/*
@@ -380,7 +377,6 @@
size_t *olen )
{
unsigned char *p = (unsigned char*)buf;
- size_t selected_identity;
*olen = 0;
@@ -401,15 +397,12 @@
MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_PRE_SHARED_KEY, p, 0 );
MBEDTLS_PUT_UINT16_BE( 2, p, 2 );
- /* NOTE: This will need to be adjusted once we support multiple PSKs
- * being offered by the client. */
- selected_identity = 0;
- MBEDTLS_PUT_UINT16_BE( selected_identity, p, 4 );
+ MBEDTLS_PUT_UINT16_BE( ssl->handshake->selected_identity, p, 4 );
*olen = 6;
- MBEDTLS_SSL_DEBUG_MSG( 4, ( "sent selected_identity: %" MBEDTLS_PRINTF_SIZET,
- selected_identity ) );
+ MBEDTLS_SSL_DEBUG_MSG( 4, ( "sent selected_identity: %u",
+ ssl->handshake->selected_identity ) );
return( 0 );
}
@@ -1709,9 +1702,7 @@
}
#if defined(MBEDTLS_KEY_EXCHANGE_SOME_PSK_ENABLED)
- MBEDTLS_SSL_DEBUG_MSG( 2, ( " mbedtls_ssl_tls13_some_psk_enabled %d",
- mbedtls_ssl_tls13_some_psk_enabled( ssl ) ) );
- if( mbedtls_ssl_tls13_some_psk_enabled( ssl ) )
+ if( mbedtls_ssl_tls13_key_exchange_mode_with_psk( ssl ) )
{
ret = ssl_tls13_write_server_pre_shared_key_ext( ssl, p, end, &output_len );
if( ret != 0 )
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 942d705..24f14e3 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -2286,30 +2286,36 @@
requires_openssl_tls1_3
requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+requires_config_enabled MBEDTLS_KEY_EXCHANGE_PSK_ENABLED
requires_config_enabled MBEDTLS_SSL_SRV_C
requires_config_enabled MBEDTLS_DEBUG_C
-run_test "TLS 1.3: psk_key_exchange_modes: basic check, O->m" \
- "$P_SRV force_version=tls13 debug_level=5" \
- "$O_NEXT_CLI -tls1_3 -psk 6162636465666768696a6b6c6d6e6f70 -allow_no_dhe_kex" \
- 0 \
+run_test "TLS 1.3: PSK: basic check, O->m" \
+ "$P_SRV force_version=tls13 tls13_kex_modes=psk debug_level=5 psk=6162636465666768696a6b6c6d6e6f70" \
+ "$O_NEXT_CLI -tls1_3 -psk 1234 -psk 6162636465666768696a6b6c6d6e6f70 -allow_no_dhe_kex" \
+ 1 \
-s "found psk key exchange modes extension" \
+ -s "found pre_shared_key extension" \
-s "Found PSK_EPHEMERAL KEX MODE" \
- -s "Found PSK KEX MODE"
+ -s "Found PSK KEX MODE" \
+ -s "Pre shared key found"
requires_gnutls_tls1_3
requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_3
requires_config_enabled MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE
+requires_config_enabled MBEDTLS_KEY_EXCHANGE_PSK_ENABLED
requires_config_enabled MBEDTLS_SSL_SRV_C
requires_config_enabled MBEDTLS_DEBUG_C
-run_test "TLS 1.3: psk_key_exchange_modes: basic check, G->m" \
- "$P_SRV force_version=tls13 debug_level=5" \
- "$G_NEXT_CLI --priority NORMAL:-VERS-ALL:+VERS-TLS1.3 \
+run_test "TLS 1.3: PSK: basic check, G->m" \
+ "$P_SRV force_version=tls13 tls13_kex_modes=psk debug_level=5 psk=6162636465666768696a6b6c6d6e6f70" \
+ "$G_NEXT_CLI --priority NORMAL:-VERS-ALL:+KX-ALL:+PSK:+DHE-PSK:+VERS-TLS1.3 \
--pskusername Client_identity --pskkey=6162636465666768696a6b6c6d6e6f70 \
localhost" \
- 0 \
+ 1 \
-s "found psk key exchange modes extension" \
+ -s "found pre_shared_key extension" \
-s "Found PSK_EPHEMERAL KEX MODE" \
- -s "Found PSK KEX MODE"
+ -s "Found PSK KEX MODE" \
+ -s "Pre shared key found"
# Tests for datagram packing
requires_config_enabled MBEDTLS_SSL_PROTO_TLS1_2