389 lines
12 KiB
HTML
389 lines
12 KiB
HTML
<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"/><link rel="stylesheet" type="text/css" href="ca65-doc-style.css"/></head><body><a href="ref_index.html"><h1>ip65 technical reference</h1></a><h1>File : ip65/udp.s</h1><pre>UDP (user datagram protocol) functions
|
|
</pre><h2 id="functions">functions</h2><table><tr><th>function</th><th>description</th></tr><tr><td id="udp_add_listener">udp_add_listener</td><td><pre>add a udp listener
|
|
inputs:
|
|
udp_callback: vector to call when udp packet arrives on specified port
|
|
AX: set to udp port to listen on
|
|
outputs:
|
|
carry flag set if too may listeners already installed, clear otherwise
|
|
</pre></td></tr><tr><td id="udp_init">udp_init</td><td><pre> initialize udp
|
|
inputs: none
|
|
outputs: none
|
|
</pre></td></tr><tr><td id="udp_process">udp_process</td><td><pre>process incoming udp packet
|
|
inputs:
|
|
eth_inp: should contain an ethernet frame encapsulating an inbound udp packet
|
|
outputs:
|
|
carry flag set if any error occured (including if no handler for specified port
|
|
was found)
|
|
carry flag clear if no error
|
|
if handler was found, an outbound message may be created, overwriting eth_outp
|
|
</pre></td></tr><tr><td id="udp_remove_listener">udp_remove_listener</td><td><pre> remove an udp listener
|
|
inputs:
|
|
AX = port to stop listening on
|
|
outputs:
|
|
carry flag clear of handler found and removed
|
|
carry flag set if handler for specified port not found
|
|
</pre></td></tr><tr><td id="udp_send">udp_send</td><td><pre>send udp packet
|
|
inputs:
|
|
udp_send_dest: destination ip address (4 bytes)
|
|
udp_send_dest_port: destination port (2 bytes)
|
|
udp_send_src_port: source port (2 bytes)
|
|
udp_send_len: length of data to send (exclusive of any headers)
|
|
AX: pointer to buffer containing data to be sent
|
|
outputs:
|
|
carry flag is set if an error occured, clear otherwise
|
|
</pre></td></tr></table><h2 id="variables">variables</h2><table><tr><th>variable</th><th>description</th><th>size (bytes)</th></tr><tr><td id="udp_callback">udp_callback</td><td>vector to routine to be called when a udp packet arrives
|
|
</td><td>2</td></tr><tr><td id="udp_send_dest">udp_send_dest</td><td>set to ip address that udp packet will be sent to
|
|
</td><td>4</td></tr><tr><td id="udp_send_dest_port">udp_send_dest_port</td><td>set to port that udp packet will be sent to
|
|
</td><td>2</td></tr><tr><td id="udp_send_len">udp_send_len</td><td>set to length of data to be sent in udp packet (excluding ethernet,ip & udp headers)
|
|
</td><td>2</td></tr><tr><td id="udp_send_src_port">udp_send_src_port</td><td>set to port that udp packet will be sent from
|
|
</td><td>2</td></tr></table><h2 id="constants">constants</h2><table><tr><th>constants</th><th>description</th><th>value</th></tr><tr><td id="udp_cksum">udp_cksum</td><td>offset of checksum field in udp packet
|
|
</td><td>6 </td></tr><tr><td id="udp_data">udp_data</td><td>offset of data in udp packet
|
|
</td><td>8 </td></tr><tr><td id="udp_dest_port">udp_dest_port</td><td>offset of destination port field in udp packet
|
|
</td><td>2 </td></tr><tr><td id="udp_inp">udp_inp</td><td>pointer to udp packet inside inbound ethernet frame
|
|
</td><td>ip_inp + ip_data </td></tr><tr><td id="udp_len">udp_len</td><td>offset of length field in udp packet
|
|
</td><td>4 </td></tr><tr><td id="udp_outp">udp_outp</td><td>pointer to udp packet inside outbound ethernet frame
|
|
</td><td>ip_outp + ip_data </td></tr><tr><td id="udp_src_port">udp_src_port</td><td>offset of source port field in udp packet
|
|
</td><td>0 </td></tr></table><h2>implementation</h2><pre id="code">;UDP (user datagram protocol) functions
|
|
|
|
.include "../inc/common.i"
|
|
.ifndef KPR_API_VERSION_NUMBER
|
|
.define EQU =
|
|
.include "../inc/kipper_constants.i"
|
|
.endif
|
|
|
|
;.import dbg_dump_udp_header
|
|
|
|
.import ip65_error
|
|
|
|
.export udp_init
|
|
.export udp_process
|
|
.export udp_add_listener
|
|
.export udp_remove_listener
|
|
.export udp_send
|
|
|
|
.export udp_callback
|
|
|
|
.export udp_inp
|
|
.export udp_outp
|
|
|
|
.exportzp udp_src_port
|
|
.exportzp udp_dest_port
|
|
.exportzp udp_len
|
|
.exportzp udp_cksum
|
|
.exportzp udp_data
|
|
|
|
.export udp_send_dest
|
|
.export udp_send_src_port
|
|
.export udp_send_dest_port
|
|
.export udp_send_len
|
|
|
|
.import ip_calc_cksum
|
|
.import ip_send
|
|
.import ip_create_packet
|
|
.import ip_inp
|
|
.import ip_outp
|
|
.importzp ip_cksum_ptr
|
|
.importzp ip_header_cksum
|
|
.importzp ip_src
|
|
.importzp ip_dest
|
|
.importzp ip_data
|
|
.importzp ip_proto
|
|
.importzp ip_proto_udp
|
|
.importzp ip_id
|
|
.importzp ip_len
|
|
|
|
.import copymem
|
|
.importzp copy_src
|
|
.importzp copy_dest
|
|
|
|
.import cfg_ip
|
|
|
|
.data
|
|
udp_cbtmp: jmp $ffff ; temporary vector - gets filled in later
|
|
|
|
|
|
.bss
|
|
|
|
; argument for udp_add_listener
|
|
udp_callback: .res 2 ;vector to routine to be called when a udp packet arrives
|
|
|
|
; arguments for udp_send
|
|
udp_send_dest: .res 4 ;set to ip address that udp packet will be sent to
|
|
udp_send_src_port: .res 2 ;set to port that udp packet will be sent from
|
|
udp_send_dest_port: .res 2 ;set to port that udp packet will be sent to
|
|
udp_send_len: .res 2 ;set to length of data to be sent in udp packet (excluding ethernet,ip & udp headers)
|
|
|
|
; udp listener callbacks
|
|
udp_cbmax = 4
|
|
udp_cbveclo: .res udp_cbmax ; table of listener vectors (lsb)
|
|
udp_cbvechi: .res udp_cbmax ; table of listener vectors (msb)
|
|
udp_cbportlo: .res udp_cbmax ; table of ports (lsb)
|
|
udp_cbporthi: .res udp_cbmax ; table of ports (msb)
|
|
udp_cbcount: .res 1 ; number of active listeners
|
|
|
|
; udp packet offsets
|
|
udp_inp = ip_inp + ip_data ;pointer to udp packet inside inbound ethernet frame
|
|
udp_outp = ip_outp + ip_data ;pointer to udp packet inside outbound ethernet frame
|
|
udp_src_port = 0 ;offset of source port field in udp packet
|
|
udp_dest_port = 2 ;offset of destination port field in udp packet
|
|
udp_len = 4 ;offset of length field in udp packet
|
|
udp_cksum = 6 ;offset of checksum field in udp packet
|
|
udp_data = 8 ;offset of data in udp packet
|
|
|
|
; virtual header
|
|
udp_vh = udp_outp - 12
|
|
udp_vh_src = 0
|
|
udp_vh_dest = 4
|
|
udp_vh_zero = 8
|
|
udp_vh_proto = 9
|
|
udp_vh_len = 10
|
|
|
|
|
|
; temp for port comparison
|
|
port: .res 2
|
|
|
|
|
|
.code
|
|
|
|
; initialize udp
|
|
; inputs: none
|
|
; outputs: none
|
|
udp_init:
|
|
lda #0
|
|
sta udp_cbcount
|
|
rts
|
|
|
|
|
|
;process incoming udp packet
|
|
;inputs:
|
|
; eth_inp: should contain an ethernet frame encapsulating an inbound udp packet
|
|
;outputs:
|
|
; carry flag set if any error occured (including if no handler for specified port
|
|
; was found)
|
|
; carry flag clear if no error
|
|
; if handler was found, an outbound message may be created, overwriting eth_outp
|
|
|
|
udp_process:
|
|
lda udp_cbcount ; any installed udp listeners?
|
|
beq @drop
|
|
|
|
tax ; check ports
|
|
dex
|
|
@checkport:
|
|
lda udp_cbportlo,x
|
|
cmp udp_inp + udp_dest_port + 1
|
|
bne :+
|
|
lda udp_cbporthi,x
|
|
cmp udp_inp + udp_dest_port
|
|
beq @handle
|
|
: dex
|
|
bpl @checkport
|
|
|
|
@drop:
|
|
sec
|
|
rts
|
|
|
|
@handle:
|
|
lda udp_cbveclo,x ; copy vector
|
|
sta udp_cbtmp + 1
|
|
lda udp_cbvechi,x
|
|
sta udp_cbtmp + 2
|
|
jsr udp_cbtmp ; call listener
|
|
clc
|
|
rts
|
|
|
|
|
|
;add a udp listener
|
|
;inputs:
|
|
; udp_callback: vector to call when udp packet arrives on specified port
|
|
; AX: set to udp port to listen on
|
|
;outputs:
|
|
; carry flag set if too may listeners already installed, clear otherwise
|
|
udp_add_listener:
|
|
sta port
|
|
stx port + 1
|
|
|
|
ldy udp_cbcount ; any listeners at all?
|
|
beq @add
|
|
cpy #udp_cbmax ; max?
|
|
beq @full
|
|
ldy #0
|
|
@check:
|
|
lda udp_cbportlo,y ; check if port is already handled
|
|
cmp port
|
|
bne :+
|
|
lda udp_cbporthi,y
|
|
cmp port + 1
|
|
beq @busy
|
|
: iny
|
|
cpy udp_cbcount
|
|
bne @check
|
|
@add:
|
|
inc udp_cbcount ; increase counter
|
|
sta udp_cbportlo,y ; add port
|
|
txa
|
|
sta udp_cbporthi,y ; add port
|
|
lda udp_callback ; and vector
|
|
sta udp_cbveclo,y
|
|
lda udp_callback + 1
|
|
sta udp_cbvechi,y
|
|
|
|
clc
|
|
rts
|
|
@full:
|
|
@busy:
|
|
lda #KPR_ERROR_LISTENER_NOT_AVAILABLE
|
|
sta ip65_error
|
|
sec
|
|
sec
|
|
rts
|
|
|
|
|
|
; remove an udp listener
|
|
; inputs:
|
|
; AX = port to stop listening on
|
|
; outputs:
|
|
; carry flag clear of handler found and removed
|
|
; carry flag set if handler for specified port not found
|
|
udp_remove_listener:
|
|
sta port
|
|
stx port + 1
|
|
|
|
ldy udp_cbcount ; any listeners installed?
|
|
beq @notfound
|
|
dey
|
|
@check:
|
|
lda udp_cbportlo,y ; check if port is handled
|
|
cmp port
|
|
bne :+
|
|
lda udp_cbporthi,y
|
|
cmp port + 1
|
|
beq @remove
|
|
: dey
|
|
bpl @check
|
|
@notfound:
|
|
sec
|
|
rts
|
|
@remove:
|
|
tya ; number of listeners below
|
|
eor #$ff
|
|
clc
|
|
adc udp_cbcount
|
|
beq @done
|
|
@move:
|
|
tax ; number of items to move
|
|
: lda udp_cbportlo + 1,y ; move ports
|
|
sta udp_cbportlo,y
|
|
lda udp_cbporthi + 1,y
|
|
sta udp_cbporthi,y
|
|
lda udp_cbveclo + 1,y ; move vectors
|
|
sta udp_cbveclo,y
|
|
lda udp_cbvechi + 1,y
|
|
sta udp_cbvechi,y
|
|
iny
|
|
dex
|
|
bne :-
|
|
@done:
|
|
dec udp_cbcount ; decrement counter
|
|
clc
|
|
rts
|
|
|
|
|
|
;send udp packet
|
|
;inputs:
|
|
; udp_send_dest: destination ip address (4 bytes)
|
|
; udp_send_dest_port: destination port (2 bytes)
|
|
; udp_send_src_port: source port (2 bytes)
|
|
; udp_send_len: length of data to send (exclusive of any headers)
|
|
; AX: pointer to buffer containing data to be sent
|
|
;outputs:
|
|
; carry flag is set if an error occured, clear otherwise
|
|
udp_send:
|
|
stax copy_src ; copy data to output buffer
|
|
ldax #udp_outp + udp_data
|
|
stax copy_dest
|
|
ldax udp_send_len
|
|
jsr copymem
|
|
|
|
ldx #3 ; copy virtual header addresses
|
|
: lda udp_send_dest,x
|
|
sta udp_vh + udp_vh_dest,x ; set virtual header destination
|
|
lda cfg_ip,x
|
|
sta udp_vh + udp_vh_src,x ; set virtual header source
|
|
dex
|
|
bpl :-
|
|
|
|
lda udp_send_src_port ; copy source port
|
|
sta udp_outp + udp_src_port + 1
|
|
lda udp_send_src_port + 1
|
|
sta udp_outp + udp_src_port
|
|
|
|
lda udp_send_dest_port ; copy destination port
|
|
sta udp_outp + udp_dest_port + 1
|
|
lda udp_send_dest_port + 1
|
|
sta udp_outp + udp_dest_port
|
|
|
|
lda #ip_proto_udp
|
|
sta udp_vh + udp_vh_proto
|
|
|
|
lda #0 ; clear checksum
|
|
sta udp_outp + udp_cksum
|
|
sta udp_outp + udp_cksum + 1
|
|
sta udp_vh + udp_vh_zero ; clear virtual header zero byte
|
|
|
|
ldax #udp_vh ; checksum pointer to virtual header
|
|
stax ip_cksum_ptr
|
|
|
|
lda udp_send_len ; copy length + 8
|
|
clc
|
|
adc #8
|
|
sta udp_outp + udp_len + 1 ; lsb for udp header
|
|
sta udp_vh + udp_vh_len + 1 ; lsb for virtual header
|
|
tay
|
|
lda udp_send_len + 1
|
|
adc #0
|
|
sta udp_outp + udp_len ; msb for udp header
|
|
sta udp_vh + udp_vh_len ; msb for virtual header
|
|
|
|
tax ; length to A/X
|
|
tya
|
|
|
|
clc ; add 12 bytes for virtual header
|
|
adc #12
|
|
bcc :+
|
|
inx
|
|
:
|
|
jsr ip_calc_cksum ; calculate checksum
|
|
stax udp_outp + udp_cksum
|
|
|
|
ldx #3 ; copy addresses
|
|
: lda udp_send_dest,x
|
|
sta ip_outp + ip_dest,x ; set ip destination address
|
|
dex
|
|
bpl :-
|
|
|
|
jsr ip_create_packet ; create ip packet template
|
|
|
|
lda udp_outp + udp_len + 1 ; ip len = udp len + 20
|
|
ldx udp_outp + udp_len
|
|
clc
|
|
adc #20
|
|
bcc :+
|
|
inx
|
|
: sta ip_outp + ip_len + 1 ; set length
|
|
stx ip_outp + ip_len
|
|
|
|
ldax #$1234 ; set ID
|
|
stax ip_outp + ip_id
|
|
|
|
lda #ip_proto_udp ; set protocol
|
|
sta ip_outp + ip_proto
|
|
|
|
;jsr dbg_dump_udp_header
|
|
|
|
jmp ip_send ; send packet, sec on error
|
|
|
|
|
|
|
|
;-- LICENSE FOR udp.s --
|
|
; The contents of this file are subject to the Mozilla Public License
|
|
; Version 1.1 (the "License"); you may not use this file except in
|
|
; compliance with the License. You may obtain a copy of the License at
|
|
; http://www.mozilla.org/MPL/
|
|
;
|
|
; Software distributed under the License is distributed on an "AS IS"
|
|
; basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
|
|
; License for the specific language governing rights and limitations
|
|
; under the License.
|
|
;
|
|
; The Original Code is ip65.
|
|
;
|
|
; The Initial Developer of the Original Code is Per Olofsson,
|
|
; MagerValp@gmail.com.
|
|
; Portions created by the Initial Developer are Copyright (C) 2009
|
|
; Per Olofsson. All Rights Reserved.
|
|
; -- LICENSE END --
|
|
</pre></body></html> |