Add test vectors for TLS 1.3 traffic key generation

Signed-off-by: Hanno Becker <hanno.becker@arm.com>
diff --git a/tests/suites/test_suite_ssl.function b/tests/suites/test_suite_ssl.function
index 8f5c9ed..36f10ca 100644
--- a/tests/suites/test_suite_ssl.function
+++ b/tests/suites/test_suite_ssl.function
@@ -3696,6 +3696,52 @@
 }
 /* END_CASE */
 
+/* BEGIN_CASE depends_on:MBEDTLS_SSL_PROTO_TLS1_3_EXPERIMENTAL */
+void ssl_tls1_3_traffic_key_generation( int hash_alg,
+                                        data_t *server_secret,
+                                        data_t *client_secret,
+                                        int desired_iv_len,
+                                        int desired_key_len,
+                                        data_t *expected_server_write_key,
+                                        data_t *expected_server_write_iv,
+                                        data_t *expected_client_write_key,
+                                        data_t *expected_client_write_iv )
+{
+    mbedtls_ssl_key_set keys;
+
+    /* Check sanity of test parameters. */
+    TEST_ASSERT( client_secret->len == server_secret->len );
+    TEST_ASSERT( expected_client_write_iv->len == expected_server_write_iv->len &&
+                 expected_client_write_iv->len == (size_t) desired_iv_len );
+    TEST_ASSERT( expected_client_write_key->len == expected_server_write_key->len &&
+                 expected_client_write_key->len == (size_t) desired_key_len );
+
+    TEST_ASSERT( mbedtls_ssl_tls1_3_make_traffic_keys(
+                     (mbedtls_md_type_t) hash_alg,
+                     client_secret->x,
+                     server_secret->x,
+                     client_secret->len /* == server_secret->len */,
+                     desired_key_len, desired_iv_len,
+                     &keys ) == 0 );
+
+    TEST_ASSERT( keys.keyLen == (size_t) desired_key_len );
+    TEST_ASSERT( keys.ivLen  == (size_t) desired_iv_len  );
+
+    TEST_ASSERT( memcmp( keys.client_write_key,
+                         expected_client_write_key->x,
+                         desired_key_len ) == 0 );
+    TEST_ASSERT( memcmp( keys.server_write_key,
+                         expected_server_write_key->x,
+                         desired_key_len ) == 0 );
+    TEST_ASSERT( memcmp( keys.client_write_iv,
+                         expected_client_write_iv->x,
+                         desired_iv_len ) == 0 );
+    TEST_ASSERT( memcmp( keys.server_write_iv,
+                         expected_server_write_iv->x,
+                         desired_iv_len ) == 0 );
+}
+/* END_CASE */
+
 /* BEGIN_CASE */
 void ssl_tls_prf( int type, data_t * secret, data_t * random,
                   char *label, data_t *result_hex_str, int exp_ret )