diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index 9a44138..30e64c4 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -559,36 +559,6 @@
 }
 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-static int ssl_write_truncated_hmac_ext( mbedtls_ssl_context *ssl,
-                                         unsigned char *buf,
-                                         const unsigned char *end,
-                                         size_t *olen )
-{
-    unsigned char *p = buf;
-
-    *olen = 0;
-
-    if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED )
-        return( 0 );
-
-    MBEDTLS_SSL_DEBUG_MSG( 3,
-        ( "client hello, adding truncated_hmac extension" ) );
-
-    MBEDTLS_SSL_CHK_BUF_PTR( p, end, 4 );
-
-    *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_TRUNCATED_HMAC >> 8 ) & 0xFF );
-    *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_TRUNCATED_HMAC      ) & 0xFF );
-
-    *p++ = 0x00;
-    *p++ = 0x00;
-
-    *olen = 4;
-
-    return( 0 );
-}
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
-
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
 static int ssl_write_encrypt_then_mac_ext( mbedtls_ssl_context *ssl,
                                            unsigned char *buf,
@@ -1304,16 +1274,6 @@
     ext_len += olen;
 #endif
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-    if( ( ret = ssl_write_truncated_hmac_ext( ssl, p + 2 + ext_len,
-                                              end, &olen ) ) != 0 )
-    {
-        MBEDTLS_SSL_DEBUG_RET( 1, "ssl_write_truncated_hmac_ext", ret );
-        return( ret );
-    }
-    ext_len += olen;
-#endif
-
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
     if( ( ret = ssl_write_encrypt_then_mac_ext( ssl, p + 2 + ext_len,
                                                 end, &olen ) ) != 0 )
@@ -1479,31 +1439,6 @@
 }
 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-static int ssl_parse_truncated_hmac_ext( mbedtls_ssl_context *ssl,
-                                         const unsigned char *buf,
-                                         size_t len )
-{
-    if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED ||
-        len != 0 )
-    {
-        MBEDTLS_SSL_DEBUG_MSG( 1,
-            ( "non-matching truncated HMAC extension" ) );
-        mbedtls_ssl_send_alert_message(
-            ssl,
-            MBEDTLS_SSL_ALERT_LEVEL_FATAL,
-            MBEDTLS_SSL_ALERT_MSG_HANDSHAKE_FAILURE );
-        return( MBEDTLS_ERR_SSL_BAD_HS_SERVER_HELLO );
-    }
-
-    ((void) buf);
-
-    ssl->session_negotiate->trunc_hmac = MBEDTLS_SSL_TRUNC_HMAC_ENABLED;
-
-    return( 0 );
-}
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
-
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 static int ssl_parse_cid_ext( mbedtls_ssl_context *ssl,
                               const unsigned char *buf,
@@ -2346,19 +2281,6 @@
             break;
 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-        case MBEDTLS_TLS_EXT_TRUNCATED_HMAC:
-            MBEDTLS_SSL_DEBUG_MSG( 3, ( "found truncated_hmac extension" ) );
-
-            if( ( ret = ssl_parse_truncated_hmac_ext( ssl,
-                            ext + 4, ext_size ) ) != 0 )
-            {
-                return( ret );
-            }
-
-            break;
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
-
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
         case MBEDTLS_TLS_EXT_CID:
             MBEDTLS_SSL_DEBUG_MSG( 3, ( "found CID extension" ) );
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 29569d1..4715129 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -543,28 +543,6 @@
 }
 #endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-static int ssl_parse_truncated_hmac_ext( mbedtls_ssl_context *ssl,
-                                         const unsigned char *buf,
-                                         size_t len )
-{
-    if( len != 0 )
-    {
-        MBEDTLS_SSL_DEBUG_MSG( 1, ( "bad client hello message" ) );
-        mbedtls_ssl_send_alert_message( ssl, MBEDTLS_SSL_ALERT_LEVEL_FATAL,
-                                        MBEDTLS_SSL_ALERT_MSG_DECODE_ERROR );
-        return( MBEDTLS_ERR_SSL_BAD_HS_CLIENT_HELLO );
-    }
-
-    ((void) buf);
-
-    if( ssl->conf->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_ENABLED )
-        ssl->session_negotiate->trunc_hmac = MBEDTLS_SSL_TRUNC_HMAC_ENABLED;
-
-    return( 0 );
-}
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
-
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
 static int ssl_parse_encrypt_then_mac_ext( mbedtls_ssl_context *ssl,
                                       const unsigned char *buf,
@@ -1703,16 +1681,6 @@
                 break;
 #endif /* MBEDTLS_SSL_MAX_FRAGMENT_LENGTH */
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-            case MBEDTLS_TLS_EXT_TRUNCATED_HMAC:
-                MBEDTLS_SSL_DEBUG_MSG( 3, ( "found truncated hmac extension" ) );
-
-                ret = ssl_parse_truncated_hmac_ext( ssl, ext + 4, ext_size );
-                if( ret != 0 )
-                    return( ret );
-                break;
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
-
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
             case MBEDTLS_TLS_EXT_CID:
                 MBEDTLS_SSL_DEBUG_MSG( 3, ( "found CID extension" ) );
@@ -1721,7 +1689,7 @@
                 if( ret != 0 )
                     return( ret );
                 break;
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
 #if defined(MBEDTLS_SSL_ENCRYPT_THEN_MAC)
             case MBEDTLS_TLS_EXT_ENCRYPT_THEN_MAC:
@@ -1967,31 +1935,6 @@
     return( 0 );
 }
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-static void ssl_write_truncated_hmac_ext( mbedtls_ssl_context *ssl,
-                                          unsigned char *buf,
-                                          size_t *olen )
-{
-    unsigned char *p = buf;
-
-    if( ssl->session_negotiate->trunc_hmac == MBEDTLS_SSL_TRUNC_HMAC_DISABLED )
-    {
-        *olen = 0;
-        return;
-    }
-
-    MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, adding truncated hmac extension" ) );
-
-    *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_TRUNCATED_HMAC >> 8 ) & 0xFF );
-    *p++ = (unsigned char)( ( MBEDTLS_TLS_EXT_TRUNCATED_HMAC      ) & 0xFF );
-
-    *p++ = 0x00;
-    *p++ = 0x00;
-
-    *olen = 4;
-}
-#endif /* MBEDTLS_SSL_TRUNCATED_HMAC */
-
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 static void ssl_write_cid_ext( mbedtls_ssl_context *ssl,
                                unsigned char *buf,
@@ -2654,11 +2597,6 @@
     ext_len += olen;
 #endif
 
-#if defined(MBEDTLS_SSL_TRUNCATED_HMAC)
-    ssl_write_truncated_hmac_ext( ssl, p + 2 + ext_len, &olen );
-    ext_len += olen;
-#endif
-
 #if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     ssl_write_cid_ext( ssl, p + 2 + ext_len, &olen );
     ext_len += olen;