Fix comments and remove hrr related code

Change-Id: Iab1fc5415b3b7f7b5bcb0a41a01f4234cc3497d6
Signed-off-by: XiaokangQian <xiaokang.qian@arm.com>
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 09fe012..3fbe6f3 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -648,7 +648,6 @@
     MBEDTLS_SSL_SERVER_HELLO_VERIFY_REQUEST_SENT,
 #if defined(MBEDTLS_SSL_PROTO_TLS1_3)
     MBEDTLS_SSL_HELLO_RETRY_REQUEST,
-    MBEDTLS_SSL_SECOND_CLIENT_HELLO,
     MBEDTLS_SSL_ENCRYPTED_EXTENSIONS,
     MBEDTLS_SSL_CLIENT_CERTIFICATE_VERIFY,
 #if defined(MBEDTLS_SSL_TLS1_3_COMPATIBILITY_MODE)
@@ -1362,7 +1361,7 @@
     void *MBEDTLS_PRIVATE(p_psk);                    /*!< context for PSK callback           */
 #endif
 
-#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY)
+#if defined(MBEDTLS_SSL_DTLS_HELLO_VERIFY) && defined(MBEDTLS_SSL_SRV_C)
     /** Callback to create & write a cookie for ClientHello veirifcation    */
     int (*MBEDTLS_PRIVATE(f_cookie_write))( void *, unsigned char **, unsigned char *,
                            const unsigned char *, size_t );
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index b23fc1d..9a7c503 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -585,10 +585,6 @@
     /*!<  Number of Hello Retry Request messages received from the server.  */
     int hello_retry_request_count;
 #endif /* MBEDTLS_SSL_CLI_C */
-#if defined(MBEDTLS_SSL_SRV_C)
-    /*!<  Number of Hello Retry Request messages sent by the server.  */
-    int hello_retry_requests_sent;
-#endif /* MBEDTLS_SSL_SRV_C */
 
 #if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
     defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
diff --git a/library/ssl_tls13_generic.c b/library/ssl_tls13_generic.c
index a6bcac3..fabc5d1 100644
--- a/library/ssl_tls13_generic.c
+++ b/library/ssl_tls13_generic.c
@@ -1518,15 +1518,16 @@
                                                size_t buf_len )
 {
     uint8_t *p = (uint8_t*)buf;
+    const uint8_t *end = buf + buf_len;
     mbedtls_ssl_handshake_params *handshake = ssl->handshake;
 
     /* Get size of the TLS opaque key_exchange field of the KeyShareEntry struct. */
+    MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 );
     uint16_t peerkey_len = MBEDTLS_GET_UINT16_BE( p, 0 );
     p += 2;
 
     /* Check if key size is consistent with given buffer length. */
-    if ( peerkey_len > ( buf_len - 2 ) )
-        return( MBEDTLS_ERR_SSL_DECODE_ERROR );
+    MBEDTLS_SSL_CHK_BUF_PTR( p, end, peerkey_len );
 
     /* Store peer's ECDH public key. */
     memcpy( handshake->ecdh_psa_peerkey, p, peerkey_len );
diff --git a/library/ssl_tls13_server.c b/library/ssl_tls13_server.c
index b172ec9..d181cd2 100644
--- a/library/ssl_tls13_server.c
+++ b/library/ssl_tls13_server.c
@@ -41,12 +41,7 @@
 
 /* From RFC 8446:
  *   struct {
- *       select (Handshake.msg_type) {
- *           case client_hello:
- *                ProtocolVersion versions<2..254>;
- *           case server_hello: // and HelloRetryRequest
- *                ProtocolVersion selected_version;
- *       };
+ *          ProtocolVersion versions<2..254>;
  *   } SupportedVersions;
  */
 static int ssl_tls13_parse_supported_versions_ext( mbedtls_ssl_context *ssl,
@@ -60,21 +55,15 @@
     const unsigned char *versions_end;
 
     MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 1 );
-
     versions_len = p[0];
     p += 1;
 
     MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, versions_len );
-    if( versions_len % 2 != 0 )
-    {
-        MBEDTLS_SSL_DEBUG_MSG( 1, ( "Invalid supported version list length %" MBEDTLS_PRINTF_SIZET,
-                                    versions_len ) );
-        return( MBEDTLS_ERR_SSL_DECODE_ERROR );
-    }
 
     versions_end = p + versions_len;
     while( p < versions_end )
     {
+        MBEDTLS_SSL_CHK_BUF_READ_PTR( p, versions_end, 2 );
         mbedtls_ssl_read_version( &major_ver, &minor_ver, ssl->conf->transport, p );
 
         /* In this implementation we only support TLS 1.3 and DTLS 1.3. */
@@ -121,7 +110,7 @@
  *       NamedGroup named_group_list<2..2^16-1>;
  *   } NamedGroupList;
  */
-static int mbedtls_ssl_tls13_parse_supported_groups_ext(
+static int ssl_tls13_parse_supported_groups_ext(
                 mbedtls_ssl_context *ssl,
                 const unsigned char *buf, const unsigned char *end )
 {
@@ -307,6 +296,7 @@
 }
 #endif /* MBEDTLS_ECDH_C */
 
+#if defined(MBEDTLS_SSL_DEBUG_C)
 static void ssl_tls13_debug_print_client_hello_exts( mbedtls_ssl_context *ssl )
 {
     ((void) ssl);
@@ -336,6 +326,7 @@
                                 "TRUE" : "FALSE" ) );
 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
 }
+#endif /* MBEDTLS_SSL_DEBUG_C */
 
 static int ssl_tls13_client_hello_has_exts( mbedtls_ssl_context *ssl,
                                       int ext_id_mask )
@@ -523,6 +514,7 @@
      * uint8 legacy_compression_method = 0;
      * ...
      */
+    p += 1;
     MBEDTLS_SSL_CHK_BUF_READ_PTR( p, end, 1 );
     if( p[0] != 0 )
     {
@@ -570,7 +562,7 @@
                  * indicates the named groups which the client supports,
                  * ordered from most preferred to least preferred.
                  */
-                ret = mbedtls_ssl_tls13_parse_supported_groups_ext( ssl, p,
+                ret = ssl_tls13_parse_supported_groups_ext( ssl, p,
                             extension_data_end );
                 if( ret != 0 )
                 {
@@ -693,7 +685,9 @@
     ssl->handshake->ciphersuite_info = ciphersuite_info;
 
     /* List all the extensions we have received */
+#if defined(MBEDTLS_SSL_DEBUG_C)
     ssl_tls13_debug_print_client_hello_exts( ssl );
+#endif /* MBEDTLS_SSL_DEBUG_C */
 
     /*
      * Determine the key exchange algorithm to use.
@@ -728,36 +722,10 @@
 
 /* Update the handshake state machine */
 
-static int ssl_tls13_postprocess_client_hello( mbedtls_ssl_context* ssl,
-                                               int hrr_required )
+static int ssl_tls13_postprocess_client_hello( mbedtls_ssl_context* ssl )
 {
     int ret = 0;
 
-    if( ssl->handshake->hello_retry_requests_sent == 0 )
-    {
-        hrr_required = SSL_CLIENT_HELLO_HRR_REQUIRED;
-    }
-
-    if( hrr_required == SSL_CLIENT_HELLO_HRR_REQUIRED )
-    {
-        /*
-         * Create stateless transcript hash for HRR
-         */
-        MBEDTLS_SSL_DEBUG_MSG( 4, ( "Reset transcript for HRR" ) );
-        ret = mbedtls_ssl_reset_transcript_for_hrr( ssl );
-        if( ret != 0 )
-        {
-            MBEDTLS_SSL_DEBUG_RET( 1, "mbedtls_ssl_reset_transcript_for_hrr",
-                                   ret );
-            return( ret );
-        }
-        mbedtls_ssl_session_reset_msg_layer( ssl, 0 );
-
-        /* Transmit Hello Retry Request */
-        mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_HELLO_RETRY_REQUEST );
-        return( 0 );
-    }
-
     ret = mbedtls_ssl_tls13_key_schedule_stage_early( ssl );
     if( ret != 0 )
     {
@@ -779,7 +747,6 @@
 {
 
     int ret = 0;
-    int hrr_required = SSL_CLIENT_HELLO_OK;
     unsigned char* buf = NULL;
     size_t buflen = 0;
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> parse client hello" ) );
@@ -791,11 +758,8 @@
 
     MBEDTLS_SSL_PROC_CHK_NEG( ssl_tls13_parse_client_hello( ssl, buf,
                                                             buf + buflen ) );
-    hrr_required = ret;
-
     MBEDTLS_SSL_DEBUG_MSG( 1, ( "postprocess" ) );
-    MBEDTLS_SSL_PROC_CHK( ssl_tls13_postprocess_client_hello( ssl,
-                                                              hrr_required ) );
+    MBEDTLS_SSL_PROC_CHK( ssl_tls13_postprocess_client_hello( ssl ) );
 
 cleanup:
 
@@ -821,7 +785,6 @@
     {
         /* start state */
         case MBEDTLS_SSL_HELLO_REQUEST:
-            ssl->handshake->hello_retry_requests_sent = 0;
             mbedtls_ssl_handshake_set_state( ssl, MBEDTLS_SSL_CLIENT_HELLO );
 
             break;
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index 416b89f..dac868f 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -10218,9 +10218,7 @@
             "$P_SRV debug_level=4 crt_file=data_files/server5.crt key_file=data_files/server5.key force_version=tls13 tickets=0" \
             "$O_NEXT_CLI -msg -tls1_3" \
             1 \
-            -s " tls13 server state: MBEDTLS_CLIENT_HELLO" \
-            -s " tls13 server state: MBEDTLS_SERVER_HELLO" \
-            -s ""SSL - The requested feature is not available"" \
+            -s " tls13 server state: MBEDTLS_SSL_CLIENT_HELLO" \
             -s "=> parse client hello" \
             -s "<= parse client hello"
 
@@ -10235,9 +10233,7 @@
             "$P_SRV debug_level=4 crt_file=data_files/server5.crt key_file=data_files/server5.key force_version=tls13 tickets=0" \
             "$G_NEXT_CLI -d 4 localhost --priority=NONE:+AES-128-GCM:+SHA256:+AEAD:+VERS-TLS1.3:%NO_TICKETS" \
             1 \
-            -s " tls13 server state: MBEDTLS_CLIENT_HELLO" \
-            -s " tls13 server state: MBEDTLS_SERVER_HELLO" \
-            -s ""SSL - The requested feature is not available"" \
+            -s " tls13 server state: MBEDTLS_SSL_CLIENT_HELLO" \
             -s "=> parse client hello" \
             -s "<= parse client hello"
 
diff --git a/tests/suites/test_suite_ssl.data b/tests/suites/test_suite_ssl.data
index 6d14086..5aa8dd0 100644
--- a/tests/suites/test_suite_ssl.data
+++ b/tests/suites/test_suite_ssl.data
@@ -3279,7 +3279,7 @@
 
 Version config: unsupported server TLS 1.3 only
 depends_on:MBEDTLS_SSL_PROTO_TLS1_3
-conf_version:MBEDTLS_SSL_IS_SERVER:MBEDTLS_SSL_TRANSPORT_STREAM:MBEDTLS_SSL_VERSION_TLS1_3:MBEDTLS_SSL_VERSION_TLS1_3:MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE
+conf_version:MBEDTLS_SSL_IS_SERVER:MBEDTLS_SSL_TRANSPORT_STREAM:3:4:3:4:0
 
 Version config: unsupported server DTLS 1.3 only
 depends_on:MBEDTLS_SSL_PROTO_TLS1_3