;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2004-2009. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; UDP.INC ;;
;; ;;
;; Part of the tcp/ip network stack for KolibriOS ;;
;; ;;
;; Written by hidnplayr@kolibrios.org ;;
;; ;;
;; GNU GENERAL PUBLIC LICENSE ;;
;; Version 2, June 1991 ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
$Revision: 1484 $
struct UDP_Packet
.SourcePort dw ?
.DestinationPort dw ?
.Length dw ? ; Length of (UDP Header + Data)
.Checksum dw ?
.Data:
ends
align 4
uglobal
UDP_PACKETS_TX rd MAX_IP
UDP_PACKETS_RX rd MAX_IP
endg
;-----------------------------------------------------------------
;
; UDP_init
;
; This function resets all UDP variables
;
; IN: /
; OUT: /
;
;-----------------------------------------------------------------
align 4
UDP_init:
xor eax, eax
mov edi, UDP_PACKETS_TX
mov ecx, 2*MAX_IP
rep stosd
ret
;-----------------------------------------------------------------
;
; UDP_Handler:
;
; Called by IPv4_handler,
; this procedure will inject the udp data diagrams in the application sockets.
;
; IN: Pointer to buffer in [esp]
; size of buffer in [esp+4]
; pointer to device struct in ebx
; UDP Packet size in ecx
; pointer to UDP Packet in edx
;
; esi = ipv4 source address
; edi = ipv4 dest address
;
; OUT: /
;
;-----------------------------------------------------------------
align 4
UDP_handler:
DEBUGF 1,"UDP_Handler, checksum:%x, size:%u\n", [edx+UDP_Packet.Checksum]:4, ecx
; First validate, checksum:
cmp [edx + UDP_Packet.Checksum], 0
jz .no_checksum
xchg edi, esi ; save ipv4 source address so we can look it up later
push edx
push esi
push edi
mov esi, edx
call UDP_checksum ; this destroys edx, ecx and esi (but not edi! :)
pop edx
cmp [edx + UDP_Packet.Checksum], 0
jnz .checksum_mismatch
.no_checksum:
DEBUGF 1,"UDP Checksum is correct\n"
; Look for a socket where
; IP Packet UDP Destination Port = local Port
; IP Packet SA = Remote IP
mov eax, net_sockets
.try_more:
mov si , [edx + UDP_Packet.DestinationPort] ; get the local port from the IP Packet's UDP header
.next_socket:
mov eax, [eax + SOCKET_head.NextPtr]
or eax, eax
jz .dump
cmp [eax + SOCKET_head.Domain], AF_INET4
jne .next_socket
cmp [eax + SOCKET_head.Type], IP_PROTO_UDP
jne .next_socket
cmp [eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.LocalPort], si
jne .next_socket
DEBUGF 1,"found socket with matching domain, type and localport\n"
; For dhcp, we must allow any remote server to respond.
; I will accept the first incoming response to be the one
; I bind to, if the socket is opened with a destination IP address of
; 255.255.255.255
cmp [eax + SOCKET_head.end + IPv4_SOCKET.RemoteIP], 0xffffffff
je .ok1
cmp [eax + SOCKET_head.end + IPv4_SOCKET.RemoteIP], edi ; edi is IPv4 destination address
jne .try_more ; Quit if the source IP is not valid, check for more sockets with this IP/PORT combination
DEBUGF 1,"Remote Ip matches\n"
.ok1:
cmp [eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.firstpacket], 0
jz .updateport
mov si, [edx + UDP_Packet.SourcePort]
cmp [eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.RemotePort], si
jne .dump
push ebx
lea ebx, [eax + SOCKET_head.lock]
call wait_mutex
pop ebx
.ok2:
DEBUGF 1,"Found valid UDP packet for socket %x\n", eax
lea esi, [edx + UDP_Packet.Data]
movzx ecx, [edx + UDP_Packet.Length]
rol cx , 8
sub cx , UDP_Packet.Data
inc [UDP_PACKETS_RX]
pop edi
add esp, 4
sub esi, edi
xchg esi, edi
jmp socket_internal_receiver
.updateport:
push ebx
lea ebx, [eax + SOCKET_head.lock]
call wait_mutex
pop ebx
mov si, [edx + UDP_Packet.SourcePort]
DEBUGF 1,"Changing remote port to: %x\n", si
mov [eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.RemotePort], si
inc [eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.firstpacket]
jmp .ok2
.checksum_mismatch:
DEBUGF 2,"UDP_Handler - checksum mismatch\n"
; mov esi, edx
; @@: ;
; lodsb ;
; DEBUGF 2,"%x ", eax:2 ;
; loop @r ;
.dump:
call kernel_free
add esp, 4 ; pop (balance stack)
DEBUGF 2,"UDP_Handler - dumping\n"
ret
;-----------------------------------------------------------------
;
; UDP_socket_send
;
; IN: eax = socket pointer
; ecx = number of bytes to send
; esi = pointer to data
;
;-----------------------------------------------------------------
align 4
UDP_socket_send:
mov edx, dword [eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.LocalPort] ; load local port and remote port at once
DEBUGF 1,"local port: %x, remote port: %x\n",\
[eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.LocalPort]:4,\
[eax + SOCKET_head.end + IPv4_SOCKET.end + UDP_SOCKET.RemotePort]:4
mov ebx, [eax + SOCKET_head.end + IPv4_SOCKET.LocalIP]
mov eax, [eax + SOCKET_head.end + IPv4_SOCKET.RemoteIP]
DEBUGF 1,"Create UDP Packet (size=%u)\n",ecx
mov di , IP_PROTO_UDP
sub esp, 8 ; Data ptr and data size will be placed here
add ecx, UDP_Packet.Data
; TODO: fill in: dx = fragment id
push edx esi
call IPv4_create_packet ; TODO: figure out a way to choose between IPv4 and IPv6
cmp edi, -1
je .fail
mov [esp + 8], eax ; pointer to buffer start
mov [esp + 8 + 4], edx ; buffer size
rol cx, 8
mov [edi + UDP_Packet.Length], cx
ror cx, 8
pop esi
push edi ecx
sub ecx, UDP_Packet.Data
add edi, UDP_Packet.Data
shr ecx, 2
rep movsd
mov ecx, [esp]
and ecx, 3
rep movsb
pop ecx edi
pop dword [edi + UDP_Packet.SourcePort] ; fill in both portnumbers
mov [edi + UDP_Packet.Checksum], 0 ; set it to zero, to calculate checksum
; Checksum
mov esi, edi
pushd [edi-4] ; destination address ; TODO: fix this, IPv4 packet could have options..
pushd [edi-8] ; source address
call UDP_checksum
inc [UDP_PACKETS_TX]
DEBUGF 1,"Sending UDP Packet to device %x\n", ebx
jmp ETH_sender
.fail:
; todo: queue the packet
add esp, 8+12+8
ret
;-----------------------------------------------------------------
;
; 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, cl ; byte[esi+UDP_Packet.Length+1]
adc dh, ch ; 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
;
; This function is called by system function 75
;
; IN: subfunction number in bl
; device number in bh
; ecx, edx, .. depends on subfunction
;
; OUT:
;
;---------------------------------------------------------------------------
align 4
UDP_API:
movzx eax, bh
shl eax, 2
test bl, bl
jz .packets_tx ; 0
dec bl
jz .packets_rx ; 1
.error:
mov eax, -1
ret
.packets_tx:
add eax, UDP_PACKETS_TX
mov eax, [eax]
ret
.packets_rx:
add eax, UDP_PACKETS_RX
mov eax, [eax]
ret