WebSVN – Kolibri OS – Blame – /kernel/trunk/network/tcp_subr.inc

Rev	Author	Line No.	Line
3545	hidnplayr	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
6913	ashmew2	3	;; Copyright (C) KolibriOS team 2004-2017. All rights reserved. ;;
3545	hidnplayr	4	;; Distributed under terms of the GNU General Public License ;;
		5	;; ;;
		6	;; Part of the TCP/IP network stack for KolibriOS ;;
		7	;; ;;
		8	;; Written by hidnplayr@kolibrios.org ;;
		9	;; ;;
		10	;; Based on the code of 4.4BSD ;;
		11	;; ;;
		12	;; GNU GENERAL PUBLIC LICENSE ;;
		13	;; Version 2, June 1991 ;;
		14	;; ;;
		15	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		16
4850	mario79	17	$Revision: 7098 $
3545	hidnplayr	18
		19	align 4
		20	iglobal
		21	TCP_backoff db 0,1,2,3,4,5,6,6,6,6,6,6,6
		22	endg
		23
6011	hidnplayr	24	macro tcp_checksum IP1, IP2 {
3545	hidnplayr	25
		26	;-------------
		27	; Pseudoheader
		28
		29	; protocol type
		30	mov edx, IP_PROTO_TCP
		31
		32	; source address
		33	add dl, byte [IP1+1]
		34	adc dh, byte [IP1+0]
		35	adc dl, byte [IP1+3]
		36	adc dh, byte [IP1+2]
		37
		38	; destination address
		39	adc dl, byte [IP2+1]
		40	adc dh, byte [IP2+0]
		41	adc dl, byte [IP2+3]
		42	adc dh, byte [IP2+2]
		43
		44	; size
		45	adc dl, cl
		46	adc dh, ch
		47
		48	adc edx, 0
		49
		50	;---------------------
		51	; Real header and data
		52
		53	push esi
		54	call checksum_1
		55	call checksum_2
		56	pop esi
		57
		58	} ; returns in dx only
		59
		60
		61
		62
6011	hidnplayr	63	macro tcp_sendseqinit ptr {
3545	hidnplayr	64
6011	hidnplayr	65	push edi ;;;; FIXME: i dont like this static use of edi
3545	hidnplayr	66	mov edi, [ptr + TCP_SOCKET.ISS]
		67	mov [ptr + TCP_SOCKET.SND_UP], edi
		68	mov [ptr + TCP_SOCKET.SND_MAX], edi
		69	mov [ptr + TCP_SOCKET.SND_NXT], edi
		70	mov [ptr + TCP_SOCKET.SND_UNA], edi
		71	pop edi
		72
		73	}
		74
		75
		76
6011	hidnplayr	77	macro tcp_rcvseqinit ptr {
3545	hidnplayr	78
		79	push edi
		80	mov edi, [ptr + TCP_SOCKET.IRS]
6476	hidnplayr	81	inc edi ; SYN ocupies a sequence number
3545	hidnplayr	82	mov [ptr + TCP_SOCKET.RCV_NXT], edi
		83	mov [ptr + TCP_SOCKET.RCV_ADV], edi
		84	pop edi
		85
		86	}
		87
		88
		89
6011	hidnplayr	90	macro tcp_init_socket socket {
3545	hidnplayr	91
		92	mov [socket + TCP_SOCKET.t_maxseg], TCP_mss_default
		93	mov [socket + TCP_SOCKET.t_flags], TF_REQ_SCALE or TF_REQ_TSTMP
		94
		95	mov [socket + TCP_SOCKET.t_srtt], TCP_time_srtt_default
		96	mov [socket + TCP_SOCKET.t_rttvar], TCP_time_rtt_default * 4
		97	mov [socket + TCP_SOCKET.t_rttmin], TCP_time_re_min
		98	;;; TODO: TCP_time_rangeset
		99
		100	mov [socket + TCP_SOCKET.SND_CWND], TCP_max_win shl TCP_max_winshift
		101	mov [socket + TCP_SOCKET.SND_SSTHRESH], TCP_max_win shl TCP_max_winshift
		102
		103
		104	}
		105
		106
5976	hidnplayr	107	;-----------------------------------------------------------------;
		108	; ;
6011	hidnplayr	109	; tcp_pull_out_of_band ;
5976	hidnplayr	110	; ;
		111	; IN: eax = ? ;
		112	; ebx = socket ptr ;
		113	; edx = tcp packet ptr ;
		114	; ;
		115	; OUT: / ;
		116	; ;
		117	;-----------------------------------------------------------------;
3545	hidnplayr	118	align 4
6011	hidnplayr	119	tcp_pull_out_of_band:
3545	hidnplayr	120
6011	hidnplayr	121	DEBUGF DEBUG_NETWORK_VERBOSE, "tcp_pull_out_of_band\n"
3545	hidnplayr	122
		123	;;;; 1282-1305
		124
		125	ret
		126
		127
		128
5976	hidnplayr	129	;-----------------------------------------------------------------;
		130	; ;
6011	hidnplayr	131	; tcp_drop ;
5976	hidnplayr	132	; ;
		133	; IN: eax = socket ptr ;
		134	; ebx = error number ;
		135	; ;
		136	; OUT: eax = socket ptr ;
		137	; ;
		138	;-----------------------------------------------------------------;
3545	hidnplayr	139	align 4
6011	hidnplayr	140	tcp_drop: ; FIXME CHECKME TODO
3545	hidnplayr	141
6011	hidnplayr	142	DEBUGF DEBUG_NETWORK_VERBOSE, "tcp_drop: %x\n", eax
3545	hidnplayr	143
		144	cmp [eax + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
		145	jb .no_syn_received
		146
		147	mov [eax + TCP_SOCKET.t_state], TCPS_CLOSED
		148
4365	hidnplayr	149	push eax
6011	hidnplayr	150	call tcp_output
4365	hidnplayr	151	pop eax
3545	hidnplayr	152
		153	;;; TODO: update stats
		154
6011	hidnplayr	155	jmp tcp_close
3545	hidnplayr	156
		157	.no_syn_received:
		158
		159	;;; TODO: update stats
		160
		161	;;; TODO: check if error code is "Connection timed out' and handle accordingly
		162
3674	hidnplayr	163	; mov [eax + SOCKET.errorcode], ebx
3545	hidnplayr	164
		165
		166
		167
5976	hidnplayr	168	;-----------------------------------------------------------------;
		169	; ;
6011	hidnplayr	170	; tcp_disconnect ;
5976	hidnplayr	171	; ;
		172	; IN: eax = socket ptr ;
		173	; ;
		174	; OUT: eax = socket ptr / 0 ;
		175	; ;
		176	;-----------------------------------------------------------------;
4366	hidnplayr	177	align 4
6011	hidnplayr	178	tcp_disconnect:
3545	hidnplayr	179
4366	hidnplayr	180	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_disconnect: %x\n", eax
3545	hidnplayr	181
4366	hidnplayr	182	cmp [eax + TCP_SOCKET.t_state], TCPS_ESTABLISHED
6011	hidnplayr	183	jb tcp_close ; Connection not yet synchronised, just get rid of the socket
3545	hidnplayr	184
4366	hidnplayr	185	; TODO: implement LINGER
3545	hidnplayr	186
6011	hidnplayr	187	call socket_is_disconnecting
		188	call tcp_usrclosed
4366	hidnplayr	189
		190	test eax, eax
		191	jz @f
		192	push eax
6011	hidnplayr	193	call tcp_output
4366	hidnplayr	194	pop eax
		195	@@:
		196	ret
		197
		198
5976	hidnplayr	199	;-----------------------------------------------------------------;
		200	; ;
6011	hidnplayr	201	; tcp_close ;
5976	hidnplayr	202	; ;
		203	; IN: eax = socket ptr ;
		204	; ;
		205	; OUT: / ;
		206	; ;
		207	;-----------------------------------------------------------------;
3545	hidnplayr	208	align 4
6011	hidnplayr	209	tcp_close:
3545	hidnplayr	210
3556	hidnplayr	211	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_close: %x\n", eax
3545	hidnplayr	212
		213	;;; TODO: update RTT and mean deviation
		214	;;; TODO: update slow start threshold
		215
6011	hidnplayr	216	call socket_is_disconnected
		217	call socket_free
3545	hidnplayr	218
6476	hidnplayr	219	inc [TCPS_closed]
		220
4366	hidnplayr	221	xor eax, eax
3545	hidnplayr	222	ret
		223
		224
		225
5976	hidnplayr	226	;-----------------------------------------------------------------;
		227	; ;
6011	hidnplayr	228	; tcp_outflags ;
5976	hidnplayr	229	; ;
		230	; IN: eax = socket ptr ;
		231	; ;
		232	; OUT: edx = flags ;
		233	; ;
		234	;-----------------------------------------------------------------;
3545	hidnplayr	235	align 4
6011	hidnplayr	236	tcp_outflags:
3545	hidnplayr	237
		238	mov edx, [eax + TCP_SOCKET.t_state]
6011	hidnplayr	239	movzx edx, byte[edx + .flaglist]
3545	hidnplayr	240
3556	hidnplayr	241	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_outflags: socket=%x flags=%x\n", eax, dl
3545	hidnplayr	242
		243	ret
		244
		245	.flaglist:
		246	db TH_RST + TH_ACK ; TCPS_CLOSED
		247	db 0 ; TCPS_LISTEN
		248	db TH_SYN ; TCPS_SYN_SENT
		249	db TH_SYN + TH_ACK ; TCPS_SYN_RECEIVED
		250	db TH_ACK ; TCPS_ESTABLISHED
		251	db TH_ACK ; TCPS_CLOSE_WAIT
		252	db TH_FIN + TH_ACK ; TCPS_FIN_WAIT_1
		253	db TH_FIN + TH_ACK ; TCPS_CLOSING
		254	db TH_FIN + TH_ACK ; TCPS_LAST_ACK
		255	db TH_ACK ; TCPS_FIN_WAIT_2
6476	hidnplayr	256	db TH_ACK ; TCPS_TIME_WAIT
3545	hidnplayr	257
		258
5976	hidnplayr	259	;-----------------------------------------------------------------;
		260	; ;
		261	; TCP_respond: Fast way to send an ACK/RST/keepalive segment. ;
		262	; ;
		263	; IN: ebx = socket ptr ;
		264	; cl = flags ;
		265	; ;
		266	; OUT: / ;
		267	; ;
		268	;-----------------------------------------------------------------;
3545	hidnplayr	269	align 4
6011	hidnplayr	270	tcp_respond:
3545	hidnplayr	271
3556	hidnplayr	272	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: socket=%x flags=%x\n", ebx, cl
3545	hidnplayr	273
		274	;---------------------
		275	; Create the IP packet
		276
		277	push cx ebx
		278	mov edx, [ebx + IP_SOCKET.LocalIP]
5842	hidnplayr	279	mov edi, [ebx + IP_SOCKET.RemoteIP]
		280	mov al, [ebx + IP_SOCKET.ttl]
		281	mov ah, IP_PROTO_TCP
		282	mov ecx, sizeof.TCP_header
5584	hidnplayr	283	mov ebx, [ebx + IP_SOCKET.device]
6011	hidnplayr	284	call ipv4_output
3545	hidnplayr	285	jz .error
		286	pop esi cx
5522	hidnplayr	287	push eax
3545	hidnplayr	288
		289	;-----------------------------------------------
		290	; Fill in the TCP header by using the socket ptr
		291
		292	mov ax, [esi + TCP_SOCKET.LocalPort]
		293	stosw
		294	mov ax, [esi + TCP_SOCKET.RemotePort]
		295	stosw
		296	mov eax, [esi + TCP_SOCKET.SND_NXT]
		297	bswap eax
		298	stosd
		299	mov eax, [esi + TCP_SOCKET.RCV_NXT]
		300	bswap eax
		301	stosd
		302	mov al, 0x50 ; Dataoffset: 20 bytes (TCP_header.DataOffset)
		303	stosb
		304	mov al, cl
		305	stosb
7098	ashmew2	306	mov eax, SOCKET_BUFFER_SIZE
		307	sub eax, [esi + STREAM_SOCKET.rcv.size]
		308	cmp eax, TCP_max_win
		309	jbe .lessthanmax
		310	mov eax, TCP_max_win
		311	.lessthanmax:
		312	mov cl, [esi + TCP_SOCKET.RCV_SCALE]
		313	shr eax, cl
		314
6913	ashmew2	315	xchg al, ah
3545	hidnplayr	316	stosw ; window
		317	xor eax, eax
		318	stosd ; checksum + urgentpointer
		319
		320	;---------------------
		321	; Fill in the checksum
		322
		323	.checksum:
		324	sub edi, sizeof.TCP_header
		325	mov ecx, sizeof.TCP_header
		326	xchg esi, edi
6011	hidnplayr	327	tcp_checksum (edi + IP_SOCKET.LocalIP), (edi + IP_SOCKET.RemoteIP)
3545	hidnplayr	328	mov [esi+TCP_header.Checksum], dx
		329
		330	;--------------------
		331	; And send the segment
		332
		333	call [ebx + NET_DEVICE.transmit]
3644	hidnplayr	334	test eax, eax
		335	jnz @f
6011	hidnplayr	336	call net_ptr_to_num4
3644	hidnplayr	337	inc [TCP_segments_tx + edi]
		338	@@:
3545	hidnplayr	339	ret
		340
		341	.error:
3556	hidnplayr	342	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: failed\n"
3545	hidnplayr	343	add esp, 2 + 4
		344
		345	ret
		346
		347
5976	hidnplayr	348	;-----------------------------------------------------------------;
		349	; ;
6011	hidnplayr	350	; tcp_respond_segment ;
5976	hidnplayr	351	; ;
		352	; IN: ebx = device ptr ;
		353	; edx = segment ptr (a previously received segment) ;
		354	; edi = ptr to IPv4 header ;
		355	; cl = flags ;
		356	; ;
		357	; OUT: / ;
		358	; ;
		359	;-----------------------------------------------------------------;
3545	hidnplayr	360	align 4
6011	hidnplayr	361	tcp_respond_segment:
3545	hidnplayr	362
5842	hidnplayr	363	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: frame=%x flags=%x\n", edx, cl
3545	hidnplayr	364
		365	;---------------------
		366	; Create the IP packet
		367
		368	push cx edx
5842	hidnplayr	369	mov edx, [edi + IPv4_header.DestinationAddress]
		370	mov edi, [edi + IPv4_header.SourceAddress]
3545	hidnplayr	371	mov ecx, sizeof.TCP_header
5842	hidnplayr	372	mov ax, IP_PROTO_TCP shl 8 + 128
6011	hidnplayr	373	call ipv4_output
3545	hidnplayr	374	jz .error
		375	pop esi cx
		376
5522	hidnplayr	377	push eax
3545	hidnplayr	378
		379	;---------------------------------------------------
		380	; Fill in the TCP header by using a received segment
		381
		382	mov ax, [esi + TCP_header.DestinationPort]
		383	stosw
		384	mov ax, [esi + TCP_header.SourcePort]
		385	stosw
		386	mov eax, [esi + TCP_header.AckNumber]
		387	bswap eax
		388	stosd
		389	xor eax, eax
		390	stosd
		391	mov al, 0x50 ; Dataoffset: 20 bytes (sizeof.TCP_header/4 shl 4)
		392	stosb
		393	mov al, cl
		394	stosb
		395	mov ax, 1280
		396	rol ax, 8
		397	stosw ; window
		398	xor eax, eax
		399	stosd ; checksum + urgentpointer
		400
		401	;---------------------
		402	; Fill in the checksum
		403
		404	lea esi, [edi - sizeof.TCP_header]
		405	mov ecx, sizeof.TCP_header
6011	hidnplayr	406	tcp_checksum (esi - sizeof.IPv4_header + IPv4_header.DestinationAddress),\ ; FIXME
3545	hidnplayr	407	(esi - sizeof.IPv4_header + IPv4_header.SourceAddress)
		408	mov [esi + TCP_header.Checksum], dx
		409
		410	;--------------------
		411	; And send the segment
		412
		413	call [ebx + NET_DEVICE.transmit]
3644	hidnplayr	414	test eax, eax
		415	jnz @f
6011	hidnplayr	416	call net_ptr_to_num4
3644	hidnplayr	417	inc [TCP_segments_tx + edi]
		418	@@:
3545	hidnplayr	419	ret
		420
		421	.error:
3556	hidnplayr	422	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: failed\n"
3545	hidnplayr	423	add esp, 2+4
		424
		425	ret
		426
		427
6011	hidnplayr	428	macro tcpt_rangeset timer, value, min, max {
3545	hidnplayr	429
		430	local .min
		431	local .max
		432	local .done
		433
		434	cmp value, min
		435	jb .min
		436	cmp value, max
		437	ja .max
		438	mov timer, value
		439	jmp .done
		440	.min:
6512	hidnplayr	441	mov timer, min
3545	hidnplayr	442	jmp .done
		443	.max:
6512	hidnplayr	444	mov timer, max
3545	hidnplayr	445	.done:
		446	}
		447
5976	hidnplayr	448	;-----------------------------------------------------------------;
		449	; ;
6011	hidnplayr	450	; tcp_set_persist ;
5976	hidnplayr	451	; ;
		452	;-----------------------------------------------------------------;
3545	hidnplayr	453	align 4
6011	hidnplayr	454	tcp_set_persist:
3545	hidnplayr	455
3556	hidnplayr	456	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_set_persist\n"
3545	hidnplayr	457
		458	; First, check if retransmit timer is not set, retransmit and persist are mutually exclusive
		459
3600	hidnplayr	460	test [eax + TCP_SOCKET.timer_flags], timer_flag_retransmission
		461	jnz .exit
3545	hidnplayr	462
		463	; calculate RTO
		464	push ebx
		465	mov ebx, [eax + TCP_SOCKET.t_srtt]
		466	shr ebx, 2
		467	add ebx, [eax + TCP_SOCKET.t_rttvar]
		468	shr ebx, 1
		469
		470	mov cl, [eax + TCP_SOCKET.t_rxtshift]
		471	shl ebx, cl
		472
		473	; Start/restart persistance timer.
		474
6011	hidnplayr	475	tcpt_rangeset [eax + TCP_SOCKET.timer_persist], ebx, TCP_time_pers_min, TCP_time_pers_max
3600	hidnplayr	476	or [ebx + TCP_SOCKET.timer_flags], timer_flag_persist
3545	hidnplayr	477	pop ebx
		478
		479	cmp [eax + TCP_SOCKET.t_rxtshift], TCP_max_rxtshift
		480	jae @f
		481	inc [eax + TCP_SOCKET.t_rxtshift]
		482	@@:
3600	hidnplayr	483	.exit:
3545	hidnplayr	484
		485	ret
		486
		487
		488
5976	hidnplayr	489	;-----------------------------------------------------------------;
		490	; ;
6011	hidnplayr	491	; tcp_xmit_timer: Calculate new smoothed RTT. ;
5976	hidnplayr	492	; ;
		493	; IN: eax = rtt ;
		494	; ebx = socket ptr ;
		495	; ;
		496	; OUT: / ;
		497	; ;
		498	;-----------------------------------------------------------------;
3545	hidnplayr	499	align 4
6011	hidnplayr	500	tcp_xmit_timer:
3545	hidnplayr	501
5976	hidnplayr	502	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_xmit_timer: socket=0x%x rtt=%d0ms\n", ebx, eax
3545	hidnplayr	503
6476	hidnplayr	504	inc [TCPS_rttupdated]
3545	hidnplayr	505
		506	cmp [ebx + TCP_SOCKET.t_rtt], 0
		507	je .no_rtt_yet
		508
		509	; srtt is stored as a fixed point with 3 bits after the binary point.
		510	; The following magic is equivalent of the smoothing algorithm in rfc793 with an alpha of .875
		511	; (srtt = rtt/8 + srtt*7/8 in fixed point)
		512	; Adjust rtt to origin 0.
		513
		514	push ecx
		515	mov ecx, [ebx + TCP_SOCKET.t_srtt]
		516	shr ecx, TCP_RTT_SHIFT
		517	sub eax, ecx
		518	dec eax
		519	pop ecx
		520
		521	add [ebx + TCP_SOCKET.t_srtt], eax
		522	ja @f
		523	mov [ebx + TCP_SOCKET.t_srtt], 1
		524	@@:
		525
		526	; We accumulate a smoothed rtt variance (actually, a smoothed mean difference),
		527	; then set the retransmit timer to smoothed rtt + 4 times the smoothed variance.
		528	; rttvar is stored as fixed point with 2 bits after the binary point.
		529	; The following is equivalent to rfc793 smoothing with an alpha of .75
		530	; (rttvar = rttvar*3/4 + delta/4) (delta = eax)
		531
		532	; get abs(eax)
		533	push edx
		534	cdq
		535	xor eax, edx
		536	sub eax, edx
		537
		538	mov edx, [ebx + TCP_SOCKET.t_rttvar]
		539	shr edx, TCP_RTTVAR_SHIFT
		540	sub eax, edx
		541	pop edx
		542
		543	add [ebx + TCP_SOCKET.t_rttvar], eax
		544	ja @f
		545	mov [ebx + TCP_SOCKET.t_rttvar], 1
		546	@@:
		547	ret
		548
		549
		550	.no_rtt_yet:
		551	push ecx
		552	mov ecx, eax
		553	shl ecx, TCP_RTT_SHIFT
		554	mov [ebx + TCP_SOCKET.t_srtt], ecx
		555
		556	shl eax, TCP_RTTVAR_SHIFT - 1
		557	mov [ebx + TCP_SOCKET.t_rttvar], eax
		558	pop ecx
		559
		560	ret
		561
		562
5976	hidnplayr	563	;-----------------------------------------------------------------;
		564	; ;
6011	hidnplayr	565	; tcp_mss: Update maximum segment size ;
5976	hidnplayr	566	; ;
		567	; IN: eax = max segment size ;
		568	; ebx = socket ptr ;
		569	; ;
		570	; OUT: / ;
		571	; ;
		572	;-----------------------------------------------------------------;
3545	hidnplayr	573	align 4
6011	hidnplayr	574	tcp_mss:
3545	hidnplayr	575
5976	hidnplayr	576	cmp eax, 1420 ; FIXME
3545	hidnplayr	577	jbe @f
		578	mov eax, 1420
		579	@@:
		580	mov [ebx + TCP_SOCKET.t_maxseg], eax
		581
		582
		583	ret
		584
		585
		586
5976	hidnplayr	587	;-----------------------------------------------------------------;
		588	; ;
6011	hidnplayr	589	; tcp_reassemble ;
5976	hidnplayr	590	; ;
		591	; IN: ebx = socket ptr ;
		592	; edx = segment ptr ;
		593	; ;
		594	; OUT: / ;
		595	; ;
		596	;-----------------------------------------------------------------;
3545	hidnplayr	597	align 4
6011	hidnplayr	598	tcp_reassemble:
3545	hidnplayr	599
5976	hidnplayr	600	;;;;; TODO
3545	hidnplayr	601
		602	ret
		603

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(root)/kernel/trunk/network/tcp_subr.inc @ 6476 – Rev 7098