* Acess2 IP Stack
* - Address Resolution Protocol
*/
+#define DEBUG 0
#include "ipstack.h"
#include "arp.h"
#include "link.h"
#define ARP_CACHE_SIZE 64
+#define ARP_MAX_AGE (60*60*1000) // 1Hr
// === IMPORTS ===
extern tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast);
// === PROTOTYPES ===
int ARP_Initialise();
- int ARP_int_Resolve4(tInterface *Interface, tIPv4 Address);
+tMacAddr ARP_Resolve4(tInterface *Interface, tIPv4 Address);
void ARP_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buffer);
// === GLOBALS ===
-struct sARP_Cache {
+struct sARP_Cache4 {
+ tIPv4 IP;
tMacAddr MAC;
- tIPv4 IP4;
- tIPv6 IP6;
Sint64 LastUpdate;
-} *gaARP_Cache;
- int giARP_CacheSpace;
+ Sint64 LastUsed;
+} *gaARP_Cache4;
+ int giARP_Cache4Space;
+tMutex glARP_Cache4;
+struct sARP_Cache6 {
+ tIPv6 IP;
+ tMacAddr MAC;
+ Sint64 LastUpdate;
+ Sint64 LastUsed;
+} *gaARP_Cache6;
+ int giARP_Cache6Space;
+tMutex glARP_Cache6;
+ int giARP_LastUpdateID = 0;
// === CODE ===
/**
*/
int ARP_Initialise()
{
- gaARP_Cache = malloc( ARP_CACHE_SIZE * sizeof(*gaARP_Cache) );
- memset( gaARP_Cache, 0, ARP_CACHE_SIZE * sizeof(*gaARP_Cache) );
- giARP_CacheSpace = ARP_CACHE_SIZE;
+ gaARP_Cache4 = malloc( ARP_CACHE_SIZE * sizeof(struct sARP_Cache4) );
+ memset( gaARP_Cache4, 0, ARP_CACHE_SIZE * sizeof(struct sARP_Cache4) );
+ giARP_Cache4Space = ARP_CACHE_SIZE;
+
+ gaARP_Cache6 = malloc( ARP_CACHE_SIZE * sizeof(struct sARP_Cache6) );
+ memset( gaARP_Cache6, 0, ARP_CACHE_SIZE * sizeof(struct sARP_Cache6) );
+ giARP_Cache6Space = ARP_CACHE_SIZE;
Link_RegisterType(0x0806, ARP_int_GetPacket);
return 1;
}
/**
- * \fn int ARP_int_Resolve4(tInterface *Interface, tIPv4 Address)
- * \brief Request the network to resolve an IPv4 Address
- * \return Boolean Success
+ * \brief Resolves a MAC address from an IPv4 address
*/
-int ARP_int_Resolve4(tInterface *Interface, tIPv4 Address)
+tMacAddr ARP_Resolve4(tInterface *Interface, tIPv4 Address)
{
+ int lastID;
+ int i;
struct sArpRequest4 req;
- req.HWType = htons(0x100); // Ethernet
+ ENTER("pInterface xAddress", Interface, Address);
+
+ Mutex_Acquire( &glARP_Cache4 );
+ for( i = 0; i < giARP_Cache4Space; i++ )
+ {
+ if(gaARP_Cache4[i].IP.L != Address.L) continue;
+
+ // Check if the entry needs to be refreshed
+ if( now() - gaARP_Cache4[i].LastUpdate > ARP_MAX_AGE ) break;
+
+ Mutex_Release( &glARP_Cache4 );
+ LOG("Return %x:%x:%x:%x:%x:%x",
+ gaARP_Cache4[i].MAC.B[0], gaARP_Cache4[i].MAC.B[1],
+ gaARP_Cache4[i].MAC.B[2], gaARP_Cache4[i].MAC.B[3],
+ gaARP_Cache4[i].MAC.B[4], gaARP_Cache4[i].MAC.B[5]
+ );
+ LEAVE('-');
+ return gaARP_Cache4[i].MAC;
+ }
+ Mutex_Release( &glARP_Cache4 );
+
+ lastID = giARP_LastUpdateID;
+
+ // Create request
+ Log_Log("ARP4", "Asking for address %i.%i.%i.%i",
+ Address.B[0], Address.B[1], Address.B[2], Address.B[3]
+ );
+ req.HWType = htons(0x0001); // Ethernet
req.Type = htons(0x0800);
req.HWSize = 6;
req.SWSize = 4;
req.DestMac = cMAC_BROADCAST;
req.DestIP = Address;
+ // Send Request
Link_SendPacket(Interface->Adapter, 0x0806, req.DestMac, sizeof(struct sArpRequest4), &req);
- return 0;
+ // Wait for a reply
+ for(;;)
+ {
+ while(lastID == giARP_LastUpdateID) Threads_Yield();
+ lastID = giARP_LastUpdateID;
+
+ Mutex_Acquire( &glARP_Cache4 );
+ for( i = 0; i < giARP_Cache4Space; i++ )
+ {
+ if(gaARP_Cache4[i].IP.L != Address.L) continue;
+
+ Mutex_Release( &glARP_Cache4 );
+ return gaARP_Cache4[i].MAC;
+ }
+ Mutex_Release( &glARP_Cache4 );
+ }
+}
+
+/**
+ * \brief Updates the ARP Cache entry for an IPv4 Address
+ */
+void ARP_UpdateCache4(tIPv4 SWAddr, tMacAddr HWAddr)
+{
+ int i;
+ int free = -1;
+ int oldest = 0;
+
+ // Find an entry for the IP address in the cache
+ Mutex_Acquire(&glARP_Cache4);
+ for( i = giARP_Cache4Space; i--; )
+ {
+ if(gaARP_Cache4[oldest].LastUpdate > gaARP_Cache4[i].LastUpdate) {
+ oldest = i;
+ }
+ if( gaARP_Cache4[i].IP.L == SWAddr.L ) break;
+ if( gaARP_Cache4[i].LastUpdate == 0 && free == -1 ) free = i;
+ }
+ // If there was no match, we need to make one
+ if(i == -1) {
+ if(free != -1)
+ i = free;
+ else
+ i = oldest;
+ gaARP_Cache4[i].IP = SWAddr;
+ }
+
+ Log_Log("ARP4", "Caching %i.%i.%i.%i (%02x:%02x:%02x:%02x:%02x:%02x) in %i",
+ SWAddr.B[0], SWAddr.B[1], SWAddr.B[2], SWAddr.B[3],
+ HWAddr.B[0], HWAddr.B[1], HWAddr.B[2], HWAddr.B[3], HWAddr.B[4], HWAddr.B[5],
+ i
+ );
+
+ gaARP_Cache4[i].MAC = HWAddr;
+ gaARP_Cache4[i].LastUpdate = now();
+ giARP_LastUpdateID ++;
+ Mutex_Release(&glARP_Cache4);
+}
+
+/**
+ * \brief Updates the ARP Cache entry for an IPv6 Address
+ */
+void ARP_UpdateCache6(tIPv6 SWAddr, tMacAddr HWAddr)
+{
+ int i;
+ int free = -1;
+ int oldest = 0;
+
+ // Find an entry for the MAC address in the cache
+ Mutex_Acquire(&glARP_Cache6);
+ for( i = giARP_Cache6Space; i--; )
+ {
+ if(gaARP_Cache6[oldest].LastUpdate > gaARP_Cache6[i].LastUpdate) {
+ oldest = i;
+ }
+ if( MAC_EQU(gaARP_Cache6[i].MAC, HWAddr) ) break;
+ if( gaARP_Cache6[i].LastUpdate == 0 && free == -1 ) free = i;
+ }
+ // If there was no match, we need to make one
+ if(i == -1) {
+ if(free != -1)
+ i = free;
+ else
+ i = oldest;
+ gaARP_Cache6[i].MAC = HWAddr;
+ }
+
+ gaARP_Cache6[i].IP = SWAddr;
+ gaARP_Cache6[i].LastUpdate = now();
+ giARP_LastUpdateID ++;
+ Mutex_Release(&glARP_Cache6);
}
/**
*/
void ARP_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buffer)
{
- int i, free = -1;
- int oldest = 0;
tArpRequest4 *req4 = Buffer;
tArpRequest6 *req6 = Buffer;
tInterface *iface;
// Sanity Check Packet
- if( Length < sizeof(tArpRequest4) ) {
- Log("[ARP ] Recieved undersized packet");
+ if( Length < (int)sizeof(tArpRequest4) ) {
+ Log_Log("ARP", "Recieved undersized packet");
return ;
}
if( ntohs(req4->Type) != 0x0800 ) {
- Log("[ARP ] Recieved a packet with a bad type 0x%x", ntohs(req4->Type));
+ Log_Log("ARP", "Recieved a packet with a bad type (0x%x)", ntohs(req4->Type));
return ;
}
if( req4->HWSize != 6 ) {
- Log("[ARP ] Recieved a packet with HWSize != 6 (%i)", req4->HWSize);
+ Log_Log("ARP", "Recieved a packet with HWSize != 6 (%i)", req4->HWSize);
return;
}
+ #if ARP_DETECT_SPOOFS
if( !MAC_EQU(req4->SourceMac, From) ) {
- Log("[ARP ] ARP spoofing detected", req4->HWSize);
+ Log_Log("ARP", "ARP spoofing detected "
+ "(%02x%02x:%02x%02x:%02x%02x != %02x%02x:%02x%02x:%02x%02x)",
+ req4->SourceMac.B[0], req4->SourceMac.B[1], req4->SourceMac.B[2],
+ req4->SourceMac.B[3], req4->SourceMac.B[4], req4->SourceMac.B[5],
+ From.B[0], From.B[1], From.B[2],
+ From.B[3], From.B[4], From.B[5]
+ );
return;
}
+ #endif
+
+ Log_Debug("ARP", "Request ID %i", ntohs(req4->Request));
- switch( req4->Request )
+ switch( ntohs(req4->Request) )
{
case 1: // You want my IP?
+ Log_Debug("ARP", "ARP Request Address class %i", req4->SWSize);
// Check what type of IP it is
switch( req4->SWSize )
{
case 4:
+ Log_Debug("ARP", "From MAC %02x:%02x:%02x:%02x:%02x:%02x",
+ req4->SourceMac.B[0], req4->SourceMac.B[1],
+ req4->SourceMac.B[2], req4->SourceMac.B[3],
+ req4->SourceMac.B[4], req4->SourceMac.B[5]);
+ //Log_Debug("ARP", "to MAC %02x:%02x:%02x:%02x:%02x:%02x",
+ // req4->DestMac.B[0], req4->DestMac.B[1],
+ // req4->DestMac.B[2], req4->DestMac.B[3],
+ // req4->DestMac.B[4], req4->DestMac.B[5]);
+ Log_Debug("ARP", "ARP Request IPv4 Address %i.%i.%i.%i from %i.%i.%i.%i",
+ req4->DestIP.B[0], req4->DestIP.B[1], req4->DestIP.B[2],
+ req4->DestIP.B[3],
+ req4->SourceIP.B[0], req4->SourceIP.B[1],
+ req4->SourceIP.B[2], req4->SourceIP.B[3]);
iface = IPv4_GetInterface(Adapter, req4->DestIP, 0);
if( iface )
{
- IP4_SET(req4->DestIP, req4->SourceIP);
+ Log_Debug("ARP", "Caching sender's IP Address");
+ ARP_UpdateCache4(req4->SourceIP, req4->SourceMac);
+
+ req4->DestIP = req4->SourceIP;
req4->DestMac = req4->SourceMac;
req4->SourceIP = iface->IP4.Address;
req4->SourceMac = Adapter->MacAddr;
req4->Request = htons(2);
+ Log_Debug("ARP", "Sending back us (%02x:%02x:%02x:%02x:%02x:%02x)",
+ req4->SourceMac.B[0], req4->SourceMac.B[1],
+ req4->SourceMac.B[2], req4->SourceMac.B[3],
+ req4->SourceMac.B[4], req4->SourceMac.B[5]);
Link_SendPacket(Adapter, 0x0806, req4->DestMac, sizeof(tArpRequest4), req4);
}
break;
case 6:
- if( Length < sizeof(tArpRequest6) ) {
- Log("[ARP ] Recieved undersized packet (IPv6)");
+ if( Length < (int)sizeof(tArpRequest6) ) {
+ Log_Log("ARP", "Recieved undersized packet (IPv6)");
return ;
}
+ Log_Debug("ARP", "ARP Request IPv6 Address %08x:%08x:%08x:%08x",
+ ntohl(req6->DestIP.L[0]), ntohl(req6->DestIP.L[1]),
+ ntohl(req6->DestIP.L[2]), ntohl(req6->DestIP.L[3])
+ );
iface = IPv6_GetInterface(Adapter, req6->DestIP, 0);
if( iface )
{
req6->SourceIP = iface->IP6.Address;
req6->SourceMac = Adapter->MacAddr;
req6->Request = htons(2);
+ Log_Debug("ARP", "Sending back us (%02x:%02x:%02x:%02x:%02x:%02x)",
+ req4->SourceMac.B[0], req4->SourceMac.B[1],
+ req4->SourceMac.B[2], req4->SourceMac.B[3],
+ req4->SourceMac.B[4], req4->SourceMac.B[5]);
Link_SendPacket(Adapter, 0x0806, req6->DestMac, sizeof(tArpRequest6), req6);
}
break;
default:
- Log("[ARP ] Unknown Protocol Address size (%i)", req4->SWSize);
+ Log_Debug("ARP", "Unknown Protocol Address size (%i)", req4->SWSize);
return ;
}
break;
- case 2: // Ooh! A response!
- // Find an entry for the MAC address in the cache
- for( i = giARP_CacheSpace; i--; )
- {
- if(gaARP_Cache[oldest].LastUpdate > gaARP_Cache[i].LastUpdate) {
- oldest = i;
- }
- if( MAC_EQU(gaARP_Cache[i].MAC, From) ) break;
- if( gaARP_Cache[i].LastUpdate == 0 && free==-1 ) free = i;
- }
- if(i + 1 == 0) {
- if(free != -1)
- i = free;
- else
- i = oldest;
- }
-
+ case 2: // Ooh! A response!
// Check what type of IP it is
switch( req4->SWSize )
{
case 4:
- gaARP_Cache[i].IP4 = req4->SourceIP;
+ ARP_UpdateCache4( req4->SourceIP, From );
break;
case 6:
- if( Length < sizeof(tArpRequest6) ) {
- Log("[ARP ] Recieved undersized packet (IPv6)");
+ if( Length < (int)sizeof(tArpRequest6) ) {
+ Log_Debug("ARP", "Recieved undersized packet (IPv6)");
return ;
}
- gaARP_Cache[i].IP6 = req6->SourceIP;
+ ARP_UpdateCache6( req6->SourceIP, From );
break;
default:
- Log("[ARP ] Unknown Protocol Address size (%i)", req4->SWSize);
+ Log_Debug("ARP", "Unknown Protocol Address size (%i)", req4->SWSize);
return ;
}
- gaARP_Cache[i].LastUpdate = now();
+ break;
+
+ default:
+ Log_Warning("ARP", "Unknown Request ID %i", ntohs(req4->Request));
break;
}
}