From 52dbda62a0da3d36305b20e4fe955edaae68857b Mon Sep 17 00:00:00 2001
From: Andres Amaya Garcia <andres.amayagarcia@arm.com>
Date: Wed, 5 Dec 2018 21:57:57 +0000
Subject: [PATCH] Fix compilation issue when DTLS and SSL_HW_RECORD_ACCEL are
 on
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Signed-off-by: Manuel Pégourié-Gonnard <manuel.pegourie-gonnard@arm.com>
---
 ChangeLog         |  6 ++++++
 library/ssl_tls.c | 24 ++++++++++++++++--------
 2 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 7a27fde5c..6ec1e7ec9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
+= mbed TLS x.x.x branch released xxxx-xx-xx
+
+Bugfix
+   * Fix compilation failure when both MBEDTLS_SSL_PROTO_DTLS and
+     MBEDTLS_SSL_HW_RECORD_ACCEL are enabled.
+
 = mbed TLS 2.16.5 branch released 2020-02-20
 
 Security
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b8f35fec5..65f59fb70 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1004,8 +1004,6 @@ int mbedtls_ssl_derive_keys( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
     if( mbedtls_ssl_hw_record_init != NULL )
     {
-        int ret = 0;
-
         MBEDTLS_SSL_DEBUG_MSG( 2, ( "going for mbedtls_ssl_hw_record_init()" ) );
 
         if( ( ret = mbedtls_ssl_hw_record_init( ssl, key1, key2, transform->keylen,
@@ -2885,15 +2883,18 @@ static void ssl_dtls_replay_reset( mbedtls_ssl_context *ssl );
 /*
  * Swap transform_out and out_ctr with the alternative ones
  */
-static void ssl_swap_epochs( mbedtls_ssl_context *ssl )
+static int ssl_swap_epochs( mbedtls_ssl_context *ssl )
 {
     mbedtls_ssl_transform *tmp_transform;
     unsigned char tmp_out_ctr[8];
+#if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
+    int ret;
+#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
 
     if( ssl->transform_out == ssl->handshake->alt_transform_out )
     {
         MBEDTLS_SSL_DEBUG_MSG( 3, ( "skip swap epochs" ) );
-        return;
+        return( 0 );
     }
 
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "swap epochs" ) );
@@ -2920,7 +2921,9 @@ static void ssl_swap_epochs( mbedtls_ssl_context *ssl )
             return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
         }
     }
-#endif
+#endif /* MBEDTLS_SSL_HW_RECORD_ACCEL */
+
+    return( 0 );
 }
 
 /*
@@ -2957,7 +2960,8 @@ int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
 
         ssl->handshake->cur_msg = ssl->handshake->flight;
         ssl->handshake->cur_msg_p = ssl->handshake->flight->p + 12;
-        ssl_swap_epochs( ssl );
+        if( ( ret = ssl_swap_epochs( ssl ) ) != 0 )
+            return( ret );
 
         ssl->handshake->retransmit_state = MBEDTLS_SSL_RETRANS_SENDING;
     }
@@ -2980,7 +2984,8 @@ int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
         if( is_finished && ssl->handshake->cur_msg_p == ( cur->p + 12 ) )
         {
             MBEDTLS_SSL_DEBUG_MSG( 2, ( "swap epochs to send finished message" ) );
-            ssl_swap_epochs( ssl );
+            if( ( ret = ssl_swap_epochs( ssl ) ) != 0 )
+                return( ret );
         }
 
         ret = ssl_get_remaining_payload_in_datagram( ssl );
@@ -3017,7 +3022,10 @@ int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl )
             if( ( max_frag_len < 12 ) || ( max_frag_len == 12 && hs_len != 0 ) )
             {
                 if( is_finished )
-                    ssl_swap_epochs( ssl );
+                {
+                    if( ( ret = ssl_swap_epochs( ssl ) ) != 0 )
+                        return( ret );
+                }
 
                 if( ( ret = mbedtls_ssl_flush_output( ssl ) ) != 0 )
                     return( ret );