From: John Hodge <tpg@mutabah.net>
Date: Mon, 21 Mar 2011 08:19:36 +0000 (+0800)
Subject: IPStack - Working on implementing IPv6
X-Git-Tag: rel0.10~155
X-Git-Url: https://git.ucc.asn.au/?a=commitdiff_plain;h=1b5bac109364b90a6169cc9bc2bbe9dd03eadb0a;p=tpg%2Facess2.git

IPStack - Working on implementing IPv6
---

diff --git a/Modules/IPStack/ipv6.c b/Modules/IPStack/ipv6.c
index 9368c3e2..d728325f 100644
--- a/Modules/IPStack/ipv6.c
+++ b/Modules/IPStack/ipv6.c
@@ -5,6 +5,7 @@
 #include "ipstack.h"
 #include "link.h"
 #include "ipv6.h"
+#include "firewall.h"
 
 // === IMPORTS ===
 extern tInterface	*gIP_Interfaces;
@@ -12,9 +13,13 @@ extern Uint32	IPv4_Netmask(int FixedBits);
 
 // === PROTOTYPES ===
  int	IPv6_Initialise();
+ int	IPv6_RegisterCallback(int ID, tIPCallback Callback);
 void	IPv6_int_GetPacket(tAdapter *Interface, tMacAddr From, int Length, void *Buffer);
 tInterface	*IPv6_GetInterface(tAdapter *Adapter, tIPv6 Address, int Broadcast);
 
+// === GLOBALS ===
+tIPCallback	gaIPv6_Callbacks[256];
+
 // === CODE ===
 /**
  * \brief Initialise the IPv6 handling code
@@ -25,6 +30,19 @@ int IPv6_Initialise()
 	return 1;
 }
 
+/**
+ * \brief Registers a callback
+ * \param ID	8-bit packet type ID
+ * \param Callback	Callback function
+ */
+int IPv6_RegisterCallback(int ID, tIPCallback Callback)
+{
+	if( ID < 0 || ID > 255 )	return 0;
+	if( gaIPv6_Callbacks[ID] )	return 0;
+	gaIPv6_Callbacks[ID] = Callback;
+	return 1;
+}
+
 /**
  * \fn void IPv6_int_GetPacket(tInterface *Interface, tMacAddr From, int Length, void *Buffer)
  * \brief Process an IPv6 Packet
@@ -33,9 +51,14 @@ int IPv6_Initialise()
  * \param Length	Packet length
  * \param Buffer	Packet data
  */
-void IPv6_int_GetPacket(tAdapter *Interface, tMacAddr From, int Length, void *Buffer)
+void IPv6_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buffer)
 {
+	tInterface	*iface;
 	tIPv6Header	*hdr = Buffer;
+	 int	ret, dataLength;
+	char	*dataPtr;
+	Uint8	nextHeader;
+	
 	if(Length < sizeof(tIPv6Header))	return;
 	
 	hdr->Head = ntohl(hdr->Head);
@@ -44,6 +67,7 @@ void IPv6_int_GetPacket(tAdapter *Interface, tMacAddr From, int Length, void *Bu
 	if( hdr->Version != 6 )
 		return;
 	
+	#if 1
 	Log_Debug("IPv6", "hdr = {");
 	Log_Debug("IPv6", " .Version       = %i", hdr->Version );
 	Log_Debug("IPv6", " .TrafficClass  = %i", hdr->TrafficClass );
@@ -54,7 +78,114 @@ void IPv6_int_GetPacket(tAdapter *Interface, tMacAddr From, int Length, void *Bu
 	Log_Debug("IPv6", " .Source        = %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x", hdr->Source );
 	Log_Debug("IPv6", " .Destination   = %04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x", hdr->Destination );
 	Log_Debug("IPv6", "}");
+	#endif
+	
+	// No checksum in IPv6
 	
+	// Check Packet length
+	if( ntohs(hdr->PayloadLength)+sizeof(tIPv6Header) > Length) {
+		Log_Log("IPv6", "hdr->PayloadLength(%i) > Length(%i)", ntohs(hdr->PayloadLength), Length);
+		return;
+	}
+	
+	// Process Options
+	nextHeader = hdr->NextHeader;
+	dataPtr = hdr->Data;
+	dataLength = hdr->PayloadLength;
+	for( ;; )
+	{
+		struct {
+			Uint8	NextHeader;
+			Uint8	Length;	// In 8-byte chunks, with 0 being 8 bytes long
+			Uint8	Data[];
+		}	*optionHdr;
+		optionHdr = (void*)dataPtr;
+		// Hop-by-hop options
+		if(nextHeader == 0)
+		{
+			// TODO: Parse the options (actually, RFC2460 doesn't specify any)
+		}
+		// Routing Options
+		else if(nextHeader == 43)
+		{
+			// TODO: Routing Header options
+		}
+		else
+		{
+			break;	// Unknown, pass on
+		}
+		nextHeader = optionHdr->NextHeader;
+		dataPtr += (optionHdr->Length + 1) * 8;	// 8-octet length (0 = 8 bytes long)
+	}
+	
+	// Get Interface (allowing broadcasts)
+	iface = IPv6_GetInterface(Adapter, hdr->Destination, 1);
+	
+	// Firewall rules
+	if( iface ) {
+		// Incoming Packets
+		ret = IPTables_TestChain("INPUT",
+			6, &hdr->Source, &hdr->Destination,
+			hdr->NextHeader, 0,
+			hdr->PayloadLength, hdr->Data
+			);
+	}
+	else {
+		// Routed packets
+		ret = IPTables_TestChain("FORWARD",
+			6, &hdr->Source, &hdr->Destination,
+			hdr->NextHeader, 0,
+			hdr->PayloadLength, hdr->Data
+			);
+	}
+	
+	switch(ret)
+	{
+	// 0 - Allow
+	case 0:	break;
+	// 1 - Silent Drop
+	case 1:
+		Log_Debug("IPv6", "Silently dropping packet");
+		return ;
+	// Unknown, silent drop
+	default:
+		return ;
+	}
+	
+	// Routing
+	if(!iface)
+	{
+		#if 0
+		tMacAddr	to;
+		tRoute	*rt;
+		
+		Log_Debug("IPv6", "Route the packet");
+		// Drop the packet if the TTL is zero
+		if( hdr->HopLimit == 0 ) {
+			Log_Warning("IPv6", "TODO: Sent ICMP-Timeout when TTL exceeded");
+			return ;
+		}
+		
+		hdr->HopLimit --;
+		
+		rt = IPStack_FindRoute(6, NULL, &hdr->Destination);	// Get the route (gets the interface)
+		//to = ARP_Resolve6(rt->Interface, hdr->Destination);	// Resolve address
+		
+		// Send packet
+		Log_Log("IPv6", "Forwarding packet");
+		Link_SendPacket(rt->Interface->Adapter, IPV6_ETHERNET_ID, to, Length, Buffer);
+		#endif
+		
+		return ;
+	}
+	
+	// Send it on
+	if( !gaIPv6_Callbacks[hdr->NextHeader] ) {
+		Log_Log("IPv6", "Unknown Protocol %i", hdr->NextHeader);
+		return ;
+	}
+	
+	gaIPv6_Callbacks[hdr->NextHeader]( iface, &hdr->Source, hdr->PayloadLength, hdr->Data );
 }
 
 /**
@@ -73,6 +204,7 @@ tInterface *IPv6_GetInterface(tAdapter *Adapter, tIPv6 Address, int Broadcast)
 	for( iface = gIP_Interfaces; iface; iface = iface->Next)
 	{
 		tIPv6	*thisAddr;
+		
 		// Check for this adapter
 		if( iface->Adapter != Adapter )	continue;
 		
@@ -87,6 +219,7 @@ tInterface *IPv6_GetInterface(tAdapter *Adapter, tIPv6 Address, int Broadcast)
 		if( !Broadcast )	continue;
 		
 		// Check for broadcast
+		// - Check first DWORDs
 		if( iface->SubnetBits > 32 && Address.L[0] != thisAddr->L[0] )
 			continue;
 		if( iface->SubnetBits > 64 && Address.L[1] != thisAddr->L[1] )
@@ -94,6 +227,7 @@ tInterface *IPv6_GetInterface(tAdapter *Adapter, tIPv6 Address, int Broadcast)
 		if( iface->SubnetBits > 96 && Address.L[2] != thisAddr->L[2] )
 			continue;
 		
+		// Check final DWORD
 		j = iface->SubnetBits / 32;
 		i = iface->SubnetBits % 32;
 		netmask = IPv4_Netmask( iface->SubnetBits % 32 );