Preparing library to use loopback device (#1020)

* Preparing library to use loopback device

* Repaired FreeRTOS_AddEndPoint() as well

* Minor changes for Doxygen

* Uncrustify: triggered by comment.

* Added IPv6.h and removed call to xIsIPv6Loopback

* Conditional compilation of xIPv6_GetIPType()

* Do not call xBadIPv4Loopback() when IPv4 is not enabled

* Repaired unit tests

* In FreeRTOS_AddEndPoint(), set next to NULL

* One more change in FreeRTOS_AddNetworkInterface()

* FreeRTOS_FillEndPoint: save pxNext before clearing entire endpoint struct

* Uncrustify: triggered by comment.

* Changes after review by Shub

* Changes after review by Shub, part 2

* Uncrustify: triggered by comment.

* Replace pxUDPPacket with pxIPacket in function prvAllowIPPacketIPv4()

* utest: replace xIPv6UnspecifiedAddress with FreeRTOS_in6addr_any

* Checked unit-tests and coverage

* ut: Repaired GetIPType loopback test

* Update test/unit-test/FreeRTOS_IPv6_ConfigDriverCheckChecksum/FreeRTOS_IPv6_ConfigDriverCheckChecksum_stubs.c

Co-authored-by: ActoryOu <[email protected]>

* Update test/unit-test/FreeRTOS_IPv6/ut.cmake

Co-authored-by: ActoryOu <[email protected]>

* Remove test for 'ipIPv4_FRAME_TYPE'

* Repairing tu again

---------

Co-authored-by: GitHub Action <[email protected]>
Co-authored-by: Monika Singh <[email protected]>
Co-authored-by: Tony Josi <[email protected]>
Co-authored-by: ActoryOu <[email protected]>

Author: 5 people

source/FreeRTOS_ARP.c

@@ -565,7 +565,12 @@ BaseType_t xCheckRequiresARPResolution( const NetworkBufferDescriptor_t * pxNetw
                        ( ucNextHeader == ipPROTOCOL_UDP ) )
                    {
                        IPv6_Type_t eType = xIPv6_GetIPType( ( const IPv6_Address_t * ) pxIPAddress );
-                       FreeRTOS_printf( ( "xCheckRequiresARPResolution: %pip type %s\n", ( void * ) pxIPAddress->ucBytes, ( eType == eIPv6_Global ) ? "Global" : ( eType == eIPv6_LinkLocal ) ? "LinkLocal" : "other" ) );
+                       FreeRTOS_debug_printf( ( "xCheckRequiresARPResolution: %pip type %s\n",
+                                                ( void * ) pxIPAddress->ucBytes,
+                                                ( eType == eIPv6_Global ) ? "Global" :
+                                                ( eType == eIPv6_LinkLocal ) ? "LinkLocal" :
+                                                ( eType == eIPv6_Loopback ) ? "Loopback" :
+                                                "other" ) );
 
                        if( eType == eIPv6_LinkLocal )
                        {

source/FreeRTOS_IP.c

@@ -1702,21 +1702,17 @@ static eFrameProcessingResult_t prvProcessUDPPacket( NetworkBufferDescriptor_t *
     /* Note the header values required prior to the checksum
      * generation as the checksum pseudo header may clobber some of
      * these values. */
-    if( ( pxUDPPacket->xEthernetHeader.usFrameType == ipIPv4_FRAME_TYPE ) &&
-        ( usLength > ( FreeRTOS_ntohs( pxUDPPacket->xIPHeader.usLength ) - uxIPHeaderSizePacket( pxNetworkBuffer ) ) ) )
-    {
-        eReturn = eReleaseBuffer;
-    }
-    else if( ( pxUDPPacket->xEthernetHeader.usFrameType == ipIPv4_FRAME_TYPE ) &&
-             ( ipFIRST_LOOPBACK_IPv4 <= ( FreeRTOS_ntohl( pxUDPPacket->xIPHeader.ulDestinationIPAddress ) ) ) &&
-             ( ( FreeRTOS_ntohl( pxUDPPacket->xIPHeader.ulDestinationIPAddress ) ) < ipLAST_LOOPBACK_IPv4 ) )
-    {
-        /* The local loopback addresses must never appear outside a host. See RFC 1122
-         * section 3.2.1.3. */
-        eReturn = eReleaseBuffer;
-    }
-    else if( ( pxNetworkBuffer->xDataLength >= uxMinSize ) &&
-             ( uxLength >= sizeof( UDPHeader_t ) ) )
+    #if ( ipconfigUSE_IPv4 != 0 )
+        if( ( pxUDPPacket->xEthernetHeader.usFrameType == ipIPv4_FRAME_TYPE ) &&
+            ( usLength > ( FreeRTOS_ntohs( pxUDPPacket->xIPHeader.usLength ) - uxIPHeaderSizePacket( pxNetworkBuffer ) ) ) )
+        {
+            eReturn = eReleaseBuffer;
+        }
+        else
+    #endif /* ( ipconfigUSE_IPv4 != 0 ) */
+
+    if( ( pxNetworkBuffer->xDataLength >= uxMinSize ) &&
+        ( uxLength >= sizeof( UDPHeader_t ) ) )
     {
         size_t uxPayloadSize_1, uxPayloadSize_2;
 

source/FreeRTOS_IPv4.c

@@ -210,6 +210,58 @@ BaseType_t xIsIPv4Multicast( uint32_t ulIPAddress )
 }
 /*-----------------------------------------------------------*/
 
+/**
+ * @brief Check if the packet is an illegal loopback packet.
+ *
+ * @param[in] pxIPHeader The IP-header being checked.
+ *
+ * @return Returns pdTRUE if the packet should be stopped, because either the source
+ *         or the target address is a loopback address.
+ */
+BaseType_t xBadIPv4Loopback( const IPHeader_t * const pxIPHeader )
+{
+    BaseType_t xReturn = pdFALSE;
+    const NetworkEndPoint_t * pxEndPoint = FreeRTOS_FindEndPointOnIP_IPv4( pxIPHeader->ulSourceIPAddress, 3 );
+
+    /* Allow loopback packets from this node itself only. */
+    if( pxEndPoint != NULL )
+    {
+        BaseType_t x1 = ( xIsIPv4Loopback( pxIPHeader->ulDestinationIPAddress ) != 0 ) ? pdTRUE : pdFALSE;
+        BaseType_t x2 = ( xIsIPv4Loopback( pxIPHeader->ulSourceIPAddress ) != 0 ) ? pdTRUE : pdFALSE;
+
+        if( x1 != x2 )
+        {
+            /* Either the source or the destination address is an IPv4 loopback address. */
+            xReturn = pdTRUE;
+        }
+    }
+
+    return xReturn;
+}
+/*-----------------------------------------------------------*/
+
+/**
+ * @brief Is the IP address an IPv4 loopback address.
+ *
+ * @param[in] ulAddress The IP address being checked.
+ *
+ * @return pdTRUE if the IP address is a loopback address or else, pdFALSE.
+ */
+BaseType_t xIsIPv4Loopback( uint32_t ulAddress )
+{
+    BaseType_t xReturn = pdFALSE;
+    uint32_t ulIP = FreeRTOS_ntohl( ulAddress );
+
+    if( ( ulIP >= ipFIRST_LOOPBACK_IPv4 ) &&
+        ( ulIP < ipLAST_LOOPBACK_IPv4 ) )
+    {
+        xReturn = pdTRUE;
+    }
+
+    return xReturn;
+}
+/*-----------------------------------------------------------*/
+
 /**
  * @brief Check whether this IPv4 packet is to be allowed or to be dropped.
  *
@@ -260,6 +312,12 @@ enum eFrameProcessingResult prvAllowIPPacketIPv4( const struct xIP_PACKET * cons
             /* Can not handle, unknown or invalid header version. */
             eReturn = eReleaseBuffer;
         }
+        else if( xBadIPv4Loopback( &( pxIPPacket->xIPHeader ) ) == pdTRUE )
+        {
+            /* The local loopback addresses must never appear outside a host. See RFC 1122
+             * section 3.2.1.3. */
+            eReturn = eReleaseBuffer;
+        }
         else if(
             ( FreeRTOS_FindEndPointOnIP_IPv4( ulDestinationIPAddress, 4 ) == NULL ) &&
             ( pxNetworkBuffer->pxEndPoint == NULL ) &&

source/FreeRTOS_IPv6.c

@@ -62,7 +62,7 @@ const struct xIPv6_Address FreeRTOS_in6addr_any = { 0 };
 /**
  * This variable is initialized by the system to contain the loopback IPv6 address.
  */
-const struct xIPv6_Address FreeRTOS_in6addr_loopback = { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1 } };
+const struct xIPv6_Address FreeRTOS_in6addr_loopback = { { 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 1U } };
 
 #if ( ipconfigDRIVER_INCLUDED_RX_IP_CHECKSUM == 1 )
     /* Check IPv6 packet length. */
@@ -237,19 +237,6 @@ const struct xIPv6_Address FreeRTOS_in6addr_loopback = { { 0, 0, 0, 0, 0, 0, 0,
 #endif /* ( ipconfigDRIVER_INCLUDED_RX_IP_CHECKSUM == 1 ) */
 /*-----------------------------------------------------------*/
 
-/**
- * This variable is initialized by the system to contain the unspecified IPv6 address.
- */
-static const struct xIPv6_Address xIPv6UnspecifiedAddress = { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 } };
-
-#if ( ipconfigETHERNET_DRIVER_FILTERS_PACKETS == 0 )
-
-/*
- * Check if the packet is a loopback packet.
- */
-    static BaseType_t xIsIPv6Loopback( const IPHeader_IPv6_t * const pxIPv6Header );
-#endif /* ipconfigETHERNET_DRIVER_FILTERS_PACKETS == 0 */
-
 /**
  * @brief Get the group ID and stored into IPv6_Address_t.
  *
@@ -270,34 +257,60 @@ static void xGetIPv6MulticastGroupID( const IPv6_Address_t * pxIPv6Address,
 
 /*-----------------------------------------------------------*/
 
+/**
+ * @brief Check if the IP-address is an IPv6 loopback address.
+ *
+ * @param[in] pxAddress The IP-address being checked.
+ *
+ * @return pdTRUE if the IP-address is a loopback address or else, pdFALSE.
+ */
+BaseType_t xIsIPv6Loopback( const IPv6_Address_t * pxAddress )
+{
+    BaseType_t xReturn = pdFALSE;
+
+    if( memcmp( pxAddress->ucBytes, FreeRTOS_in6addr_loopback.ucBytes, ipSIZE_OF_IPv6_ADDRESS ) == 0 )
+    {
+        xReturn = pdTRUE;
+    }
+
+    return xReturn;
+}
+
 #if ( ipconfigETHERNET_DRIVER_FILTERS_PACKETS == 0 )
 
 /**
- * @brief Check if the packet is a loopback packet.
+ * @brief Check if the packet is an illegal loopback packet.
  *
- * @param[in] pxIPv6Header The IP packet in pxNetworkBuffer.
+ * @param[in] pxIPv6Header The IP-header of the packet.
  *
- * @return Returns pdTRUE if it's a legal loopback packet, pdFALSE if not .
+ * @return Returns pdTRUE if the packet should be stopped, because either the source
+ *         or the target address is a loopback address.
  */
 /* MISRA Ref 8.9.1 [File scoped variables] */
 /* More details at: https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/blob/main/MISRA.md#rule-89 */
 /* coverity[misra_c_2012_rule_8_9_violation] */
 /* coverity[single_use] */
-    static BaseType_t xIsIPv6Loopback( const IPHeader_IPv6_t * const pxIPv6Header )
+    BaseType_t xBadIPv6Loopback( const IPHeader_IPv6_t * const pxIPv6Header )
     {
         BaseType_t xReturn = pdFALSE;
         const NetworkEndPoint_t * pxEndPoint = FreeRTOS_FindEndPointOnIP_IPv6( &( pxIPv6Header->xSourceAddress ) );
 
         /* Allow loopback packets from this node itself only. */
-        if( ( pxEndPoint != NULL ) &&
-            ( memcmp( pxIPv6Header->xDestinationAddress.ucBytes, FreeRTOS_in6addr_loopback.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) &&
-            ( memcmp( pxIPv6Header->xSourceAddress.ucBytes, pxEndPoint->ipv6_settings.xIPAddress.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) )
+        if( pxEndPoint != NULL )
         {
-            xReturn = pdTRUE;
+            BaseType_t x1 = ( xIsIPv6Loopback( &( pxIPv6Header->xDestinationAddress ) ) != 0 ) ? pdTRUE : pdFALSE;
+            BaseType_t x2 = ( xIsIPv6Loopback( &( pxIPv6Header->xSourceAddress ) ) != 0 ) ? pdTRUE : pdFALSE;
+
+            if( x1 != x2 )
+            {
+                /* Either source or the destination address is a loopback address. */
+                xReturn = pdTRUE;
+            }
         }
 
         return xReturn;
     }
+
 #endif /* ipconfigETHERNET_DRIVER_FILTERS_PACKETS == 0 */
 
 
@@ -332,7 +345,7 @@ BaseType_t xIsIPv6AllowedMulticast( const IPv6_Address_t * pxIPAddress )
          * - ..
          * - 0xFF0F:: */
         else if( ( IPv6MC_GET_FLAGS_VALUE( pxIPAddress ) == 0U ) &&
-                 ( memcmp( xGroupIDAddress.ucBytes, xIPv6UnspecifiedAddress.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) )
+                 ( memcmp( xGroupIDAddress.ucBytes, FreeRTOS_in6addr_any.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) )
         {
             xReturn = pdFALSE;
         }
@@ -462,8 +475,8 @@ eFrameProcessingResult_t prvAllowIPPacketIPv6( const IPHeader_IPv6_t * const pxI
 
         /* Drop if packet has unspecified IPv6 address (defined in RFC4291 - sec 2.5.2)
          * either in source or destination address. */
-        if( ( memcmp( pxDestinationIPAddress->ucBytes, xIPv6UnspecifiedAddress.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) ||
-            ( memcmp( pxSourceIPAddress->ucBytes, xIPv6UnspecifiedAddress.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) )
+        if( ( memcmp( pxDestinationIPAddress->ucBytes, FreeRTOS_in6addr_any.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) ||
+            ( memcmp( pxSourceIPAddress->ucBytes, FreeRTOS_in6addr_any.ucBytes, sizeof( IPv6_Address_t ) ) == 0 ) )
         {
             xHasUnspecifiedAddress = pdTRUE;
         }
@@ -476,10 +489,9 @@ eFrameProcessingResult_t prvAllowIPPacketIPv6( const IPHeader_IPv6_t * const pxI
             eReturn = eProcessBuffer;
         }
         /* Is it the legal multicast address? */
-        else if( ( xHasUnspecifiedAddress == pdFALSE ) &&
+        else if( ( ( xHasUnspecifiedAddress == pdFALSE ) &&
+                   ( xBadIPv6Loopback( pxIPv6Header ) == pdFALSE ) ) &&
                  ( ( xIsIPv6AllowedMulticast( pxDestinationIPAddress ) != pdFALSE ) ||
-                   /* Is it loopback address sent from this node? */
-                   ( xIsIPv6Loopback( pxIPv6Header ) != pdFALSE ) ||
                    /* Or (during DHCP negotiation) we have no IP-address yet? */
                    ( FreeRTOS_IsNetworkUp() == 0 ) ) )
         {

source/FreeRTOS_ND.c

@@ -1254,7 +1254,8 @@
 
         if( xResult == pdPASS )
         {
-            configASSERT( ( uxPrefixLength > 0U ) && ( uxPrefixLength < ( 8U * ipSIZE_OF_IPv6_ADDRESS ) ) );
+            /* A loopback IP-address has a prefix of 128. */
+            configASSERT( ( uxPrefixLength > 0U ) && ( uxPrefixLength <= ( 8U * ipSIZE_OF_IPv6_ADDRESS ) ) );
 
             if( uxPrefixLength >= 8U )
             {