X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=KernelLand%2FModules%2FIPStack%2Fipv4.c;h=000fe3966381c15393074d029408a5326ce31e30;hb=8a3c7218fb65c46c0876b7033b732188be91ae03;hp=86301e97abf55005033577896a228398e10fd4ec;hpb=48743e39650eb1ef988380e9d95f27fd40d3a9ce;p=tpg%2Facess2.git diff --git a/KernelLand/Modules/IPStack/ipv4.c b/KernelLand/Modules/IPStack/ipv4.c index 86301e97..000fe396 100644 --- a/KernelLand/Modules/IPStack/ipv4.c +++ b/KernelLand/Modules/IPStack/ipv4.c @@ -2,19 +2,21 @@ * Acess2 IP Stack * - IPv4 Protcol Handling */ -#define DEBUG 1 +#define DEBUG 0 #include "ipstack.h" #include "link.h" #include "ipv4.h" +#include "hwaddr_cache.h" #include "firewall.h" +// === CONSTANTS === #define DEFAULT_TTL 32 +#define IPV4_TRACE 1 // set to 1 to enable packet tracing // === IMPORTS === extern tInterface *gIP_Interfaces; extern void ICMP_Initialise(); extern int ICMP_Ping(tInterface *Interface, tIPv4 Addr); -extern tMacAddr ARP_Resolve4(tInterface *Interface, tIPv4 Address); // === PROTOTYPES === int IPv4_Initialise(); @@ -62,15 +64,16 @@ int IPv4_RegisterCallback(int ID, tIPCallback Callback) * \param Data Packet Data * \return Boolean Success */ -int IPv4_SendPacket(tInterface *Iface, tIPv4 Address, int Protocol, int ID, int Length, const void *Data) +int IPv4_SendPacket(tInterface *Iface, tIPv4 Address, int Protocol, int ID, tIPStackBuffer *Buffer) { tMacAddr to; - int bufSize = sizeof(tIPv4Header) + Length; - char buf[bufSize]; - tIPv4Header *hdr = (void*)buf; - int ret; + tIPv4Header hdr; + int length; + + length = IPStack_Buffer_GetLength(Buffer); - to = ARP_Resolve4(Iface, Address); + // --- Resolve destination MAC address + to = HWCache_Resolve(Iface, &Address); if( MAC_EQU(to, cMAC_ZERO) ) { // No route to host Log_Notice("IPv4", "No route to host %i.%i.%i.%i", @@ -78,40 +81,49 @@ int IPv4_SendPacket(tInterface *Iface, tIPv4 Address, int Protocol, int ID, int return 0; } - // OUTPUT Firewall rule go here - ret = IPTables_TestChain("OUTPUT", + // --- Handle OUTPUT firewall rules + // TODO: Update firewall rules for tIPStackBuffer + #if 0 + int ret = IPTables_TestChain("OUTPUT", 4, (tIPv4*)Iface->Address, &Address, Protocol, 0, - Length, Data); + length, Data); if(ret > 0) { // Just drop it (with an error) Log_Notice("IPv4", "Firewall dropped packet"); return 0; } + #endif + + // --- Initialise header + hdr.Version = 4; + hdr.HeaderLength = sizeof(tIPv4Header)/4; + hdr.DiffServices = 0; // TODO: Check - memcpy(&hdr->Options[0], Data, Length); - hdr->Version = 4; - hdr->HeaderLength = sizeof(tIPv4Header)/4; - hdr->DiffServices = 0; // TODO: Check - - hdr->Reserved = 0; - hdr->DontFragment = 0; - hdr->MoreFragments = 0; - hdr->FragOffLow = 0; - hdr->FragOffHi = 0; - - hdr->TotalLength = htons( bufSize ); - hdr->Identifcation = htons( ID ); // TODO: Check - hdr->TTL = DEFAULT_TTL; - hdr->Protocol = Protocol; - hdr->HeaderChecksum = 0; // Will be set later - hdr->Source = *(tIPv4*)Iface->Address; - hdr->Destination = Address; - hdr->HeaderChecksum = htons( IPv4_Checksum(hdr, sizeof(tIPv4Header)) ); + hdr.Reserved = 0; + hdr.DontFragment = 0; + hdr.MoreFragments = 0; + hdr.FragOffLow = 0; + hdr.FragOffHi = 0; + hdr.TotalLength = htons( sizeof(tIPv4Header) + length ); + hdr.Identifcation = htons( ID ); // TODO: Check + hdr.TTL = DEFAULT_TTL; + hdr.Protocol = Protocol; + hdr.HeaderChecksum = 0; // Will be set later + hdr.Source = *(tIPv4*)Iface->Address; + hdr.Destination = Address; + + // Actually set checksum (zeroed above) + hdr.HeaderChecksum = htons( IPv4_Checksum(&hdr, sizeof(tIPv4Header)) ); + + IPStack_Buffer_AppendSubBuffer(Buffer, sizeof(tIPv4Header), 0, &hdr, NULL, NULL); + + #if IPV4_TRACE Log_Log("IPv4", "Sending packet to %i.%i.%i.%i", Address.B[0], Address.B[1], Address.B[2], Address.B[3]); - Link_SendPacket(Iface->Adapter, IPV4_ETHERNET_ID, to, bufSize, buf); + #endif + Link_SendPacket(Iface->Adapter, IPV4_ETHERNET_ID, to, Buffer); return 1; } @@ -172,11 +184,13 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff // TODO: Handle packet fragmentation - - Log_Debug("IPv4", " From %i.%i.%i.%i to %i.%i.%i.%i", + #if IPV4_TRACE + Log_Debug("IPv4", "Proto 0x%x From %i.%i.%i.%i to %i.%i.%i.%i", + hdr->Protocol, hdr->Source.B[0], hdr->Source.B[1], hdr->Source.B[2], hdr->Source.B[3], hdr->Destination.B[0], hdr->Destination.B[1], hdr->Destination.B[2], hdr->Destination.B[3] ); + #endif // Get Data and Data Length dataLength = ntohs(hdr->TotalLength) - sizeof(tIPv4Header); @@ -196,6 +210,13 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff } else { // Routed packets + // Drop the packet if the TTL is zero + if( hdr->TTL == 0 ) { + Log_Warning("IPv4", "TODO: Send ICMP-Timeout when TTL exceeded"); + return ; + } + hdr->TTL --; + ret = IPTables_TestChain("FORWARD", 4, &hdr->Source, &hdr->Destination, hdr->Protocol, 0, @@ -222,36 +243,16 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff // Routing if(!iface) { - tMacAddr to; - tRoute *rt; - - Log_Debug("IPv4", "Route the packet"); - // Drop the packet if the TTL is zero - if( hdr->TTL == 0 ) { - Log_Warning("IPv4", "TODO: Send ICMP-Timeout when TTL exceeded"); - return ; - } - - hdr->TTL --; - - rt = IPStack_FindRoute(4, NULL, &hdr->Destination); // Get the route (gets the interface) - if( !rt || !rt->Interface ) - return ; - to = ARP_Resolve4(rt->Interface, hdr->Destination); // Resolve address - if( MAC_EQU(to, cMAC_ZERO) ) - return ; - - // Send packet - Log_Log("IPv4", "Forwarding packet to %i.%i.%i.%i (via %i.%i.%i.%i)", - hdr->Destination.B[0], hdr->Destination.B[1], - hdr->Destination.B[2], hdr->Destination.B[3], - ((tIPv4*)rt->NextHop)->B[0], ((tIPv4*)rt->NextHop)->B[1], - ((tIPv4*)rt->NextHop)->B[2], ((tIPv4*)rt->NextHop)->B[3]); - Link_SendPacket(rt->Interface->Adapter, IPV4_ETHERNET_ID, to, Length, Buffer); - - + //IPStack_RoutePacket(4, &hdr->Destination, Length, Buffer); return ; } + + // Populate ARP cache from recieved packets + // - Should be safe + if( IPStack_CompareAddress(4, &hdr->Source, iface->Address, iface->SubnetBits) ) + { + HWCache_Set(Adapter, 4, &hdr->Source, &From); + } // Send it on if( !gaIPv4_Callbacks[hdr->Protocol] ) { @@ -271,7 +272,7 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff */ tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast) { - tInterface *iface = NULL; + tInterface *iface = NULL, *zero_iface = NULL; Uint32 netmask; Uint32 addr, this; @@ -289,7 +290,20 @@ tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast) LEAVE('p', iface); return iface; } - + + LOG("iface->Address = 0x%x", *(Uint32*)iface->Address); + + if( *(Uint32*)iface->Address == 0 ) { + if( zero_iface ) { + Log_Notice("IPv4", "Multiple 0.0.0.0 interfaces on the same adapter, ignoring"); + } + else { + zero_iface = iface; + LOG("Zero IF %p", iface); + } + continue ; + } + if( !Broadcast ) continue; // Check for broadcast @@ -304,6 +318,17 @@ tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast) return iface; } } + + // Special case for intefaces that are being DHCP configured + // - If the interface address is 0.0.0.0, then if there is no match for the + // destination the packet is treated as if it was addressed to 0.0.0.0 + if( zero_iface && Broadcast ) + { + LOG("Using 0.0.0.0 interface with magic!"); + LEAVE('p', zero_iface); + return zero_iface; + } + LEAVE('n'); return NULL; } @@ -337,6 +362,7 @@ Uint32 IPv4_Netmask(int FixedBits) */ Uint16 IPv4_Checksum(const void *Buf, size_t Length) { + //Debug_HexDump("IPv4_Checksum", Buf, Length); const Uint16 *words = Buf; Uint32 sum = 0; int i;