kolibrios/kernel/branches/kolibri-cfg/network/udp.inc
CleverMouse 7b2b309d03 kernel branch with configurable boot
git-svn-id: svn://kolibrios.org@1942 a494cfbc-eb01-0410-851d-a64ba20cac60
2011-05-30 10:27:45 +00:00

156 lines
5.1 KiB
PHP

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;; ;;
;; Copyright (C) KolibriOS team 2004-2008. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License ;;
;; ;;
;; ;;
;; UDP.INC ;;
;; ;;
;; UDP Processes for Menuet OS TCP/IP stack ;;
;; ;;
;; Copyright 2002 Mike Hibbett, mikeh@oceanfree.net ;;
;; ;;
;; See file COPYING for details ;;
;; ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
$Revision$
;*******************************************************************
; Interface
;
; udp_rx Handles received IP packets with the UDP protocol
;
;*******************************************************************
;
; UDP Payload ( Data field in IP datagram )
;
; 0 1 2 3
; 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
;
; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
; | Source Port | Destination Port |
; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
; | Length ( UDP Header + Data ) | Checksum |
; +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
; | UDP Data |
; +-+-+-.......... -+
;
struc UDP_PACKET
{ .SourcePort dw ? ;+00
.DestinationPort dw ? ;+02
.Length dw ? ;+04 - Length of (UDP Header + Data)
.Checksum dw ? ;+06
.Data db ? ;+08
}
virtual at 0
UDP_PACKET UDP_PACKET
end virtual
;***************************************************************************
; Function
; udp_rx [by Johnny_B]
;
; Description
; UDP protocol handler
; This is a kernel function, called by ip_rx
; IP buffer address given in edx
; IP buffer number in eax
; Free up (or re-use) IP buffer when finished
;
;***************************************************************************
proc udp_rx stdcall
push eax
; First validate the header & checksum. Discard buffer if error
; Look for a socket where
; IP Packet UDP Destination Port = local Port
; IP Packet SA = Remote IP
mov ax, [edx + 20 + UDP_PACKET.DestinationPort] ; get the local port from
; the IP packet's UDP header
mov ebx, net_sockets
.next_socket:
mov ebx, [ebx + SOCKET.NextPtr]
or ebx, ebx
jz .exit ; No match, so exit
cmp [ebx + SOCKET.LocalPort], ax ; ax will hold the 'wrong' value,
; but the comparision is correct
jne .next_socket ; Return back if no match
; 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 [ebx + SOCKET.RemoteIP], 0xffffffff
je @f
mov eax, [edx + IP_PACKET.SourceAddress] ; get the Source address from the IP packet
cmp [ebx + SOCKET.RemoteIP], eax
jne .exit ; Quit if the source IP is not valid
@@: ; OK - we have a valid UDP packet for this socket.
; First, update the sockets remote port number with the incoming msg
; - it will have changed
; from the original ( 69 normally ) to allow further connects
mov ax, [edx + 20 + UDP_PACKET.SourcePort] ; get the UDP source port
; ( was 69, now new )
mov [ebx + SOCKET.RemotePort], ax
; Now, copy data to socket. We have socket address as [eax + sockets].
; We have IP packet in edx
; get # of bytes in ecx
movzx ecx, [edx + IP_PACKET.TotalLength] ; total length of IP packet. Subtract
xchg cl, ch ; 20 + 8 gives data length
sub ecx, 28
mov eax, [ebx + SOCKET.rxDataCount] ; get # of bytes already in buffer
add [ebx + SOCKET.rxDataCount], ecx ; increment the count of bytes in buffer
; ecx has count, edx points to data
add edx, 28 ; edx now points to the data
lea edi, [ebx + eax + SOCKETHEADERSIZE]
mov esi, edx
cld
rep movsb ; copy the data across
; flag an event to the application
mov eax, [ebx + SOCKET.PID] ; get socket owner PID
mov ecx, 1
mov esi, TASK_DATA + TASKDATA.pid
.next_pid:
cmp [esi], eax
je .found_pid
inc ecx
add esi, 0x20
cmp ecx, [TASK_COUNT]
jbe .next_pid
jmp .exit
.found_pid:
shl ecx, 8
or [ecx + SLOT_BASE + APPDATA.event_mask], EVENT_NETWORK ; stack event
mov [check_idle_semaphore], 200
.exit:
pop eax
call freeBuff ; Discard the packet
ret
endp