Networking - Working on DHCP client (and related changes)

[tpg/acess2.git] / Modules / IPStack / ipv4.c

diff --git a/Modules/IPStack/ipv4.c b/Modules/IPStack/ipv4.c
index 69f029c..86301e9 100644 (file)
--- a/Modules/IPStack/ipv4.c
+++ b/Modules/IPStack/ipv4.c
@@ -2,6 +2,7 @@
  * Acess2 IP Stack
  * - IPv4 Protcol Handling
  */
+#define DEBUG  1
 #include "ipstack.h"
 #include "link.h"
 #include "ipv4.h"
@@ -21,7 +22,7 @@ extern tMacAddr       ARP_Resolve4(tInterface *Interface, tIPv4 Address);
 void   IPv4_int_GetPacket(tAdapter *Interface, tMacAddr From, int Length, void *Buffer);
 tInterface     *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast);
 Uint32 IPv4_Netmask(int FixedBits);
-Uint16 IPv4_Checksum(const void *Buf, int Size);
+Uint16 IPv4_Checksum(const void *Buf, size_t Length);
  int   IPv4_Ping(tInterface *Iface, tIPv4 Addr);
 
 // === GLOBALS ===
@@ -63,14 +64,17 @@ int IPv4_RegisterCallback(int ID, tIPCallback Callback)
  */
 int IPv4_SendPacket(tInterface *Iface, tIPv4 Address, int Protocol, int ID, int Length, const void *Data)
 {
-       tMacAddr        to = ARP_Resolve4(Iface, Address);
-       const tMacAddr  zero = {{0,0,0,0,0,0}};
+       tMacAddr        to;
         int    bufSize = sizeof(tIPv4Header) + Length;
        char    buf[bufSize];
        tIPv4Header     *hdr = (void*)buf;
         int    ret;
        
-       if( MAC_EQU(to, zero) ) {
+       to = ARP_Resolve4(Iface, Address);
+       if( MAC_EQU(to, cMAC_ZERO) ) {
+               // No route to host
+               Log_Notice("IPv4", "No route to host %i.%i.%i.%i",
+                       Address.B[0], Address.B[1], Address.B[2], Address.B[3]);
                return 0;
        }
        
@@ -79,8 +83,9 @@ int IPv4_SendPacket(tInterface *Iface, tIPv4 Address, int Protocol, int ID, int
                4, (tIPv4*)Iface->Address, &Address,
                Protocol, 0,
                Length, Data);
-       if(ret != 0) {
+       if(ret > 0) {
                // Just drop it (with an error)
+               Log_Notice("IPv4", "Firewall dropped packet");
                return 0;
        }
        
@@ -102,7 +107,7 @@ int IPv4_SendPacket(tInterface *Iface, tIPv4 Address, int Protocol, int ID, int
        hdr->HeaderChecksum = 0;        // Will be set later
        hdr->Source = *(tIPv4*)Iface->Address;
        hdr->Destination = Address;
-       hdr->HeaderChecksum = htons(IPv4_Checksum(hdr, sizeof(tIPv4Header)));
+       hdr->HeaderChecksum = htons( IPv4_Checksum(hdr, sizeof(tIPv4Header)) );
        
        Log_Log("IPv4", "Sending packet to %i.%i.%i.%i",
                Address.B[0], Address.B[1], Address.B[2], Address.B[3]);
@@ -121,7 +126,7 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff
        Uint8   *data;
         int    dataLength;
         int    ret;
-        
+       
        if(Length < sizeof(tIPv4Header))        return;
        
        #if 0
@@ -168,6 +173,11 @@ 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",
+               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]
+               );
+       
        // Get Data and Data Length
        dataLength = ntohs(hdr->TotalLength) - sizeof(tIPv4Header);
        data = &hdr->Options[0];
@@ -200,8 +210,12 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff
        case 1:
                Log_Debug("IPv4", "Silently dropping packet");
                return ;
+       case -1:
+               // Bad rule
+               break ;
        // Unknown, silent drop
        default:
+               Log_Warning("IPv4", "Unknown firewall rule");
                return ;
        }
        
@@ -214,14 +228,18 @@ void IPv4_int_GetPacket(tAdapter *Adapter, tMacAddr From, int Length, void *Buff
                Log_Debug("IPv4", "Route the packet");
                // Drop the packet if the TTL is zero
                if( hdr->TTL == 0 ) {
-                       Log_Warning("IPv4", "TODO: Sent ICMP-Timeout when TTL exceeded");
+                       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)",
@@ -256,27 +274,37 @@ tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast)
        tInterface      *iface = NULL;
        Uint32  netmask;
        Uint32  addr, this;
-       
+
+       ENTER("pAdapter xAddress bBroadcast", Adapter, Address, Broadcast);     
+
        addr = ntohl( Address.L );
+       LOG("addr = 0x%x", addr);
        
        for( iface = gIP_Interfaces; iface; iface = iface->Next)
        {
                if( iface->Adapter != Adapter ) continue;
                if( iface->Type != 4 )  continue;
-               if( IP4_EQU(Address, *(tIPv4*)iface->Address) )
+               if( IP4_EQU(Address, *(tIPv4*)iface->Address) ) {
+                       LOG("Exact match");
+                       LEAVE('p', iface);
                        return iface;
+               }
                
                if( !Broadcast )        continue;
                
-               this = ntohl( ((tIPv4*)iface->Address)->L );
-               
                // Check for broadcast
+               this = ntohl( ((tIPv4*)iface->Address)->L );
                netmask = IPv4_Netmask(iface->SubnetBits);
-               
-               if( (addr & netmask) == (this & netmask)
-                && (addr & ~netmask) == (0xFFFFFFFF & ~netmask) )
+               LOG("iface addr = 0x%x, netmask = 0x%x (bits = %i)", this, netmask, iface->SubnetBits);
+
+               if( (addr & netmask) == (this & netmask) && (addr & ~netmask) == (0xFFFFFFFF & ~netmask) )
+               {
+                       LOG("Broadcast match");
+                       LEAVE('p', iface);
                        return iface;
+               }
        }
+       LEAVE('n');
        return NULL;
 }
 
@@ -289,8 +317,13 @@ tInterface *IPv4_GetInterface(tAdapter *Adapter, tIPv4 Address, int Broadcast)
 Uint32 IPv4_Netmask(int FixedBits)
 {
        Uint32  ret = 0xFFFFFFFF;
-       ret >>= (32-FixedBits);
-       ret <<= (32-FixedBits);
+       if( FixedBits == 0 )
+               return 0;
+       if( FixedBits < 32 )
+       {
+               ret >>= (32-FixedBits);
+               ret <<= (32-FixedBits);
+       }
        // Returns a native endian netmask
        return ret;
 }
@@ -302,18 +335,19 @@ Uint32 IPv4_Netmask(int FixedBits)
  * 
  * One's complement sum of all 16-bit words (bitwise inverted)
  */
-Uint16 IPv4_Checksum(const void *Buf, int Size)
+Uint16 IPv4_Checksum(const void *Buf, size_t Length)
 {
+       const Uint16    *words = Buf;
        Uint32  sum = 0;
-       const Uint16    *arr = Buf;
         int    i;
        
-       Size = (Size + 1) >> 1; // 16-bit word count
-       for(i = 0; i < Size; i++ )
+       // Sum all whole words
+       for(i = 0; i < Length/2; i++ )
        {
-               Uint16  val = ntohs(arr[i]);
-               sum += val;
+               sum += ntohs(words[i]);
        }
+       if( Length & 1 )
+               sum += ntohs( words[i] & 0xFF );
        
        // Apply one's complement
        while (sum >> 16)