Renames pxSocket->u.xUDP.ucMulticastTTL to xMulticastTTL so it can be used for both IPv4 and IPv6

Adds more socket option defines to cover IPv6 as well as source-specific multicast

Author: Emil Popov

source/FreeRTOS_DNS_Networking.c

@@ -87,7 +87,7 @@
             #if ( ipconfigSUPPORT_IP_MULTICAST != 0 )
                 /* Since this socket may be used for LLMNR or mDNS, set the multicast TTL to 1. */
                 uint8_t ucMulticastTTL = 1;
-                ( void ) FreeRTOS_setsockopt( xSocket, 0, FREERTOS_SO_IP_MULTICAST_TTL, &( ucMulticastTTL ), sizeof( uint8_t ) );
+                ( void ) FreeRTOS_setsockopt( xSocket, 0, FREERTOS_SO_IP_MULTICAST_TTL, &( ucMulticastTTL ), sizeof( ucMulticastTTL ) );
             #endif
         }
 

source/FreeRTOS_Sockets.c

@@ -750,7 +750,7 @@ Socket_t FreeRTOS_socket( BaseType_t xDomain,
                 #endif /* ipconfigUDP_MAX_RX_PACKETS > 0 */
 
                 #if ( ipconfigSUPPORT_IP_MULTICAST != 0 )
-                    pxSocket->u.xUDP.ucMulticastTTL = ipconfigMULTICAST_DEFAULT_TTL;
+                    pxSocket->u.xUDP.xMulticastTTL = ipconfigMULTICAST_DEFAULT_TTL;
                     vListInitialise( &pxSocket->u.xUDP.xMulticastGroupsList );
                 #endif
             }
@@ -1450,7 +1450,7 @@ static int32_t prvSendUDPPacket( const FreeRTOS_Socket_t * pxSocket,
     #if ( ipconfigSUPPORT_IP_MULTICAST != 0 )
         if( xIsIPv4Multicast( pxDestinationAddress->sin_address.ulIP_IPv4 ) )
         {
-            pxNetworkBuffer->ucSendTTL = pxSocket->u.xUDP.ucMulticastTTL;
+            pxNetworkBuffer->ucSendTTL = ( uint8_t ) pxSocket->u.xUDP.xMulticastTTL;
         }
         else
         {
@@ -2969,6 +2969,7 @@ BaseType_t FreeRTOS_setsockopt( Socket_t xSocket,
 
                 #if ( ipconfigSUPPORT_IP_MULTICAST != 0 )
                     case FREERTOS_SO_IP_MULTICAST_TTL:
+                    case FREERTOS_SO_IPV6_MULTICAST_HOPS:
                     case FREERTOS_SO_IP_ADD_MEMBERSHIP:
                     case FREERTOS_SO_IP_DROP_MEMBERSHIP:
                         xReturn = prvSetMulticastSocketOption( xSocket, lLevel, lOptionName, pvOptionValue, uxOptionLength );
@@ -6420,15 +6421,46 @@ void * pvSocketGetSocketID( const ConstSocket_t xSocket )
         {
             case FREERTOS_SO_IP_MULTICAST_TTL:
 
-                if( ( pxSocket->ucProtocol != ( uint8_t ) FREERTOS_IPPROTO_UDP ) || ( uxOptionLength != sizeof( uint8_t ) ) )
+				{
+					uint8_t ucValue = *( ( uint8_t * ) pvOptionValue );
+					
+					if( ( ( pxSocket->bits.bIsIPv6 == pdTRUE_UNSIGNED ) || pxSocket->ucProtocol != ( uint8_t ) FREERTOS_IPPROTO_UDP ) || ( uxOptionLength != sizeof( ucValue ) ) )
                 {
                     break; /* will return -pdFREERTOS_ERRNO_EINVAL */
                 }
 
                 /* Override the default TTL value with this one. */
-                pxSocket->u.xUDP.ucMulticastTTL = *( ( uint8_t * ) pvOptionValue );
+					pxSocket->u.xUDP.xMulticastTTL = ( BaseType_t ) ucValue;
 
                 xReturn = 0;
+				}
+            break;
+
+            case FREERTOS_SO_IPV6_MULTICAST_HOPS:
+				{
+					BaseType_t xValue = *( ( BaseType_t * ) pvOptionValue );
+	            
+					if( ( pxSocket->bits.bIsIPv6 == pdFALSE_UNSIGNED ) || ( pxSocket->ucProtocol != ( uint8_t ) FREERTOS_IPPROTO_UDP ) || ( uxOptionLength != sizeof( BaseType_t ) ) )
+					{
+						break; /* will return -pdFREERTOS_ERRNO_EINVAL */
+					}
+
+					if ( ( xValue < -1 ) || ( xValue > 255 ) )
+					{
+						break; /* will return -pdFREERTOS_ERRNO_EINVAL */
+					}else if ( xValue == -1 )
+					{
+						/* Set the default TTL value. */
+						pxSocket->u.xUDP.xMulticastTTL = ipconfigUDP_TIME_TO_LIVE;
+					}
+					else
+					{
+						/* Override the default TTL value with this one. */
+						pxSocket->u.xUDP.xMulticastTTL = xValue;
+					}
+
+					xReturn = 0;
+				}
                 break;
 
             case FREERTOS_SO_IP_ADD_MEMBERSHIP:

source/include/FreeRTOSIPConfigDefaults.h

@@ -1169,7 +1169,8 @@
 
 /* Specifies the TTL value that will be used for multicast
  * UDP packets by default. Can be overridden per socket by
- * setting the FREERTOS_SO_IP_MULTICAST_TTL socket option. */
+ * setting the FREERTOS_SO_IP_MULTICAST_TTL socket option or by
+ * setting the FREERTOS_SO_IPV6_MULTICAST_HOPS in case of an IPv6 socket. */
 #ifndef ipconfigMULTICAST_DEFAULT_TTL
     #define ipconfigMULTICAST_DEFAULT_TTL    ( 1 )
 #endif

source/include/FreeRTOS_IP_Private.h

@@ -649,10 +649,14 @@ typedef struct UDPSOCKET
     #endif /* ipconfigUSE_CALLBACKS */
     #if ( ipconfigSUPPORT_IP_MULTICAST != 0 )
         List_t xMulticastGroupsList;
-        uint8_t ucMulticastTTL; /**< Allows for multicast sockets to use a different TTL value to limit the scope of the multicast packet. Usually set to 1.
+        BaseType_t xMulticastTTL; /**< Allows for multicast sockets to use a different TTL value to limit the scope of the multicast packet. Usually set to 1.
+                                 * Note that the options are of different sizes for IPv4 and IPv6.
                                  * Example:
-                                 * uint8_t ucMulticastTTL = 1;
-                                 * FreeRTOS_setsockopt( MCastSendSock, 0, FREERTOS_SO_IP_MULTICAST_TTL, ( void * ) &ucMulticastTTL, sizeof( uint8_t ) );
+                                 * uint8_t ttl = 1;
+                                 * FreeRTOS_setsockopt( MCastSendSock, 0, FREERTOS_SO_IP_MULTICAST_TTL, ( void * ) &ttl, sizeof( ttl ) );
+								 * IPv6 Example:
+                                 * BaseType_t hops = 1;
+                                 * FreeRTOS_setsockopt( MCastSendSock_v6, 0, FREERTOS_SO_IPV6_MULTICAST_HOPS, ( void * ) &hops, sizeof( hops ) );
                                  */
     #endif
 } IPUDPSocket_t;

source/include/FreeRTOS_Sockets.h

@@ -154,7 +154,12 @@
     #if ( ipconfigSUPPORT_IP_MULTICAST != 0 )
         #define FREERTOS_SO_IP_MULTICAST_TTL              ( 19 ) /* TTL value to me used when sending multicast packets. Defaults to ipconfigMULTICAST_DEFAULT_TTL */
         #define FREERTOS_SO_IP_ADD_MEMBERSHIP             ( 20 ) /* Mark the socket as able to receive multicast messages from a multicast group address */
-        #define FREERTOS_SO_IP_DROP_MEMBERSHIP            ( 21 ) /* Remove membership from a multicast group address */
+        #define FREERTOS_SO_IP_ADD_SOURCE_MEMBERSHIP      ( 21 ) /* not implemented */
+        #define FREERTOS_SO_IP_DROP_MEMBERSHIP            ( 22 ) /* Remove membership from a multicast group address */
+        #define FREERTOS_SO_IP_DROP_SOURCE_MEMBERSHIP     ( 23 ) /* not implemented */
+        #define FREERTOS_SO_IPV6_ADD_MEMBERSHIP           ( 24 ) /* Same as FREERTOS_SO_IP_ADD_MEMBERSHIP but for IPv6 */
+        #define FREERTOS_SO_IPV6_DROP_MEMBERSHIP          ( 25 ) /* Same as FREERTOS_SO_IP_DROP_MEMBERSHIP but for IPv6 */
+        #define FREERTOS_SO_IPV6_MULTICAST_HOPS           ( 26 ) /* Similar to FREERTOS_SO_IP_MULTICAST_TTL but for IPv6. Defaults to ipconfigMULTICAST_DEFAULT_TTL */
     #endif /* (ipconfigSUPPORT_IP_MULTICAST != 0) */
 
     #define FREERTOS_INADDR_ANY                           ( 0U ) /* The 0.0.0.0 IPv4 address. */