* Acess2 IP Stack
* - IPv4 Protcol Handling
*/
-#define DEBUG 1
+#define DEBUG 0
#include "ipstack.h"
#include "link.h"
#include "ipv4.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);
+extern void ARP_UpdateCache4(tIPv4 SWAddr, tMacAddr HWAddr);
// === PROTOTYPES ===
int IPv4_Initialise();
* \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);
+ // --- Resolve destination MAC address
to = ARP_Resolve4(Iface, Address);
if( MAC_EQU(to, cMAC_ZERO) ) {
// No route to host
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;
}
// TODO: Handle packet fragmentation
-
+ #if IPV4_TRACE
Log_Debug("IPv4", " From %i.%i.%i.%i to %i.%i.%i.%i",
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);
data = &hdr->Options[0];
+
+ // Populate ARP cache from sniffing.
+ // - Downside: Poisoning, polluting from routed packets
+ //ARP_UpdateCache4(hdr->Source, From);
// Get Interface (allowing broadcasts)
iface = IPv4_GetInterface(Adapter, hdr->Destination, 1);
// Routing
if(!iface)
{
+ #if 0
tMacAddr to;
tRoute *rt;
-
+
+
+ // TODO: Put this in another thread to avoid delays in the RX thread
Log_Debug("IPv4", "Route the packet");
// Drop the packet if the TTL is zero
if( hdr->TTL == 0 ) {
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);
-
+ Log_Warning("IPv4", "TODO: Implement forwarding with tIPStackBuffer");
+// Link_SendPacket(rt->Interface->Adapter, IPV4_ETHERNET_ID, to, Length, Buffer);
+ #endif
return ;
}
+
+ // Populate ARP cache from recieved packets
+ // - Should be safe
+ ARP_UpdateCache4(hdr->Source, From);
// Send it on
if( !gaIPv4_Callbacks[hdr->Protocol] ) {
*/
tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast)
{
- tInterface *iface = NULL;
+ tInterface *iface = NULL, *zero_iface = NULL;
Uint32 netmask;
Uint32 addr, this;
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
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;
}
git.ucc.asn.au / tpg / acess2.git / blobdiff
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