| 67,7 → 67,7 |
|---|
| ; size of buffer in [esp+4] |
| ; pointer to device struct in ebx |
| ; UDP Packet size in ecx |
| ; pointer to UDP Packet data in edx |
| ; pointer to UDP Packet in edx |
| ; OUT: / |
| ; |
| ;----------------------------------------------------------------- |
| 74,36 → 74,25 |
|---|
| align 4 |
| UDP_handler: |
| |
| DEBUGF 1,"UDP_Handler\n" |
| DEBUGF 1,"UDP_Handler, checksum:%x\n", [edx+UDP_Packet.Checksum]:4 |
| |
| ; First validate, checksum: |
| cmp [edx + UDP_Packet.Checksum], 0 |
| jz .no_checksum |
| ; First validate, checksum: |
| |
| pusha |
| push ecx edx |
| |
| push cx |
| rol word [esp], 8 |
| push word IP_PROTO_UDP shl 8 |
| push esi |
| push edi |
| push esi |
| |
| mov di, [edx + UDP_Packet.Checksum] |
| mov [edx + UDP_Packet.Checksum], 0 |
| |
| mov esi, edx |
| xor edx, edx |
| call checksum_1 |
| call checksum_pseudoheader |
| call checksum_2 |
| call UDP_checksum |
| |
| cmp di, dx |
| popa |
| jne .checksum_mismatch ;dump |
| pop edx ecx |
| |
| cmp [edx + UDP_Packet.Checksum], 0 |
| jnz .checksum_mismatch |
| |
| .no_checksum: |
| |
| DEBUGF 1,"UDP Checksum is correct\n" |
| |
| ; Look for a socket where |
| 190,12 → 179,11 |
|---|
| |
| DEBUGF 2,"UDP_Handler - checksum mismatch\n" |
| |
| mov esi, [esp] |
| mov ecx, [esp + 4] |
| @@: ; |
| lodsb ; |
| DEBUGF 2,"%x ", eax:2 ; |
| loop @r ; |
| ; mov esi, edx |
| ; @@: ; |
| ; lodsb ; |
| ; DEBUGF 2,"%x ", eax:2 ; |
| ; loop @r ; |
| |
| .dump: |
| call kernel_free |
| 230,9 → 218,7 |
|---|
| DEBUGF 1,"Create UDP Packet (size=%u)\n",ecx |
| |
| mov di , IP_PROTO_UDP |
| sub esp, 8 ; reserve some place in stack for later |
| ; Create a part of the pseudoheader in stack, |
| push dword IP_PROTO_UDP shl 8 |
| sub esp, 8 ; Data ptr and data size will be placed here |
| add ecx, UDP_Packet.Data |
| |
| ; TODO: fill in: dx = fragment id |
| 242,12 → 228,11 |
|---|
| cmp edi, -1 |
| je .fail |
| |
| mov [esp + 8 + 4], eax ; pointer to buffer start |
| mov [esp + 8 + 4 + 4], edx ; buffer size |
| mov [esp + 8], eax ; pointer to buffer start |
| mov [esp + 8 + 4], edx ; buffer size |
| |
| rol cx, 8 |
| mov [edi + UDP_Packet.Length], cx |
| mov [esp + 8 + 2], cx |
| ror cx, 8 |
| |
| pop esi |
| 264,22 → 249,16 |
|---|
| pop dword [edi + UDP_Packet.SourcePort] ; fill in both portnumbers |
| mov [edi + UDP_Packet.Checksum], 0 ; set it to zero, to calculate checksum |
| |
| ; Checksum for UDP header + data |
| xor edx, edx |
| ; Checksum |
| mov esi, edi |
| call checksum_1 |
| ; Checksum for pseudoheader |
| pushd [edi-4] ; destination address ; TODO: fix this, IPv4 packet could have options.. |
| pushd [edi-8] ; source address |
| call checksum_pseudoheader |
| ; Now create the final checksum and store it in UDP header |
| call checksum_2 |
| mov [edi + UDP_Packet.Checksum], dx |
| call UDP_checksum |
| |
| inc [UDP_PACKETS_TX] |
| |
| DEBUGF 1,"Sending UDP Packet to device %x\n", ebx ; |
| jmp ETH_sender ; |
| DEBUGF 1,"Sending UDP Packet to device %x\n", ebx |
| jmp ETH_sender |
| |
| .fail: |
| ; todo: queue the packet |
| 289,6 → 268,73 |
|---|
| |
| |
| |
| ;----------------------------------------------------------------- |
| ; |
| ; checksum_udp |
| ; |
| ; This is the fast procedure to create or check a UDP header |
| ; - To create a new checksum, the checksum field must be set to 0 before computation |
| ; - To check an existing checksum, leave the checksum as is, |
| ; and it will be 0 after this procedure, if it was correct |
| ; |
| ; IN: push source ip |
| ; push dest ip |
| ; esi = packet ptr |
| ; |
| ; OUT: checksum is filled in in packet! (but also in dx) |
| ; |
| ;----------------------------------------------------------------- |
| |
| align 4 |
| UDP_checksum: |
| |
| ; Pseudoheader |
| mov edx, IP_PROTO_UDP ; NO shl 8 here ! (it took me ages to figure this one out) |
| |
| add dl, [esp+1+4] |
| adc dh, [esp+0+4] |
| adc dl, [esp+3+4] |
| adc dh, [esp+2+4] |
| |
| adc dl, [esp+1+8] |
| adc dh, [esp+0+8] |
| adc dl, [esp+3+8] |
| adc dh, [esp+2+8] |
| |
| adc dl, byte[esi+UDP_Packet.Length+1] |
| adc dh, byte[esi+UDP_Packet.Length+0] |
| |
| ; Done with pseudoheader, now do real header |
| adc dl, byte[esi+UDP_Packet.SourcePort+1] |
| adc dh, byte[esi+UDP_Packet.SourcePort+0] |
| |
| adc dl, byte[esi+UDP_Packet.DestinationPort+1] |
| adc dh, byte[esi+UDP_Packet.DestinationPort+0] |
| |
| adc dl, byte[esi+UDP_Packet.Length+1] |
| adc dh, byte[esi+UDP_Packet.Length+0] |
| |
| adc edx, 0 |
| |
| ; Done with header, now do data |
| push esi |
| movzx ecx, [esi+UDP_Packet.Length] |
| rol cx , 8 |
| sub cx , UDP_Packet.Data |
| add esi, UDP_Packet.Data |
| |
| call checksum_1 |
| call checksum_2 |
| pop esi |
| |
| neg [esi+UDP_Packet.Checksum] ; zero will stay zero so we just get the checksum |
| add [esi+UDP_Packet.Checksum], dx ; , else we will get (new checksum - old checksum) in the end, wich should be 0 :) |
| |
| ret 8 |
| |
| |
| |
| |
| ;--------------------------------------------------------------------------- |
| ; |
| ; UDP_API |