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

Rev	Author	Line No.	Line
3545	hidnplayr	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
7974	hidnplayr	3	;; Copyright (C) KolibriOS team 2004-2020. 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: 7974 $
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
7680	hidnplayr	92	; new tcp control block
		93
3545	hidnplayr	94	mov [socket + TCP_SOCKET.t_maxseg], TCP_mss_default
		95	mov [socket + TCP_SOCKET.t_flags], TF_REQ_SCALE or TF_REQ_TSTMP
		96
		97	mov [socket + TCP_SOCKET.t_srtt], TCP_time_srtt_default
		98	mov [socket + TCP_SOCKET.t_rttvar], TCP_time_rtt_default * 4
		99	mov [socket + TCP_SOCKET.t_rttmin], TCP_time_re_min
		100	;;; TODO: TCP_time_rangeset
		101
		102	mov [socket + TCP_SOCKET.SND_CWND], TCP_max_win shl TCP_max_winshift
		103	mov [socket + TCP_SOCKET.SND_SSTHRESH], TCP_max_win shl TCP_max_winshift
		104
7974	hidnplayr	105	mov [socket + TCP_SOCKET.RCV_SCALE], 0
		106	mov [socket + TCP_SOCKET.SND_SCALE], 0
3545	hidnplayr	107
		108	}
		109
		110
5976	hidnplayr	111	;-----------------------------------------------------------------;
		112	; ;
6011	hidnplayr	113	; tcp_pull_out_of_band ;
5976	hidnplayr	114	; ;
		115	; IN: eax = ? ;
		116	; ebx = socket ptr ;
		117	; edx = tcp packet ptr ;
		118	; ;
		119	; OUT: / ;
		120	; ;
		121	;-----------------------------------------------------------------;
3545	hidnplayr	122	align 4
6011	hidnplayr	123	tcp_pull_out_of_band:
3545	hidnplayr	124
6011	hidnplayr	125	DEBUGF DEBUG_NETWORK_VERBOSE, "tcp_pull_out_of_band\n"
3545	hidnplayr	126
		127	;;;; 1282-1305
		128
		129	ret
		130
		131
		132
5976	hidnplayr	133	;-----------------------------------------------------------------;
		134	; ;
6011	hidnplayr	135	; tcp_drop ;
5976	hidnplayr	136	; ;
		137	; IN: eax = socket ptr ;
		138	; ebx = error number ;
		139	; ;
		140	; OUT: eax = socket ptr ;
		141	; ;
		142	;-----------------------------------------------------------------;
3545	hidnplayr	143	align 4
7974	hidnplayr	144	tcp_drop:
3545	hidnplayr	145
7974	hidnplayr	146	;;; TODO: check if error code is "Connection timed out' and handle accordingly
		147
6011	hidnplayr	148	DEBUGF DEBUG_NETWORK_VERBOSE, "tcp_drop: %x\n", eax
3545	hidnplayr	149
		150	cmp [eax + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
		151	jb .no_syn_received
		152
		153	mov [eax + TCP_SOCKET.t_state], TCPS_CLOSED
		154
4365	hidnplayr	155	push eax
6011	hidnplayr	156	call tcp_output
4365	hidnplayr	157	pop eax
3545	hidnplayr	158
7974	hidnplayr	159	inc [TCPS_drops]
3545	hidnplayr	160
7974	hidnplayr	161	mov [eax + SOCKET.errorcode], ebx
6011	hidnplayr	162	jmp tcp_close
3545	hidnplayr	163
		164	.no_syn_received:
7974	hidnplayr	165	inc [TCPS_conndrops]
3545	hidnplayr	166
7974	hidnplayr	167	mov [eax + SOCKET.errorcode], ebx
		168	jmp tcp_close
3545	hidnplayr	169
		170
5976	hidnplayr	171	;-----------------------------------------------------------------;
		172	; ;
6011	hidnplayr	173	; tcp_disconnect ;
5976	hidnplayr	174	; ;
		175	; IN: eax = socket ptr ;
		176	; ;
		177	; OUT: eax = socket ptr / 0 ;
		178	; ;
		179	;-----------------------------------------------------------------;
4366	hidnplayr	180	align 4
6011	hidnplayr	181	tcp_disconnect:
3545	hidnplayr	182
4366	hidnplayr	183	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_disconnect: %x\n", eax
3545	hidnplayr	184
4366	hidnplayr	185	cmp [eax + TCP_SOCKET.t_state], TCPS_ESTABLISHED
6011	hidnplayr	186	jb tcp_close ; Connection not yet synchronised, just get rid of the socket
3545	hidnplayr	187
4366	hidnplayr	188	; TODO: implement LINGER
3545	hidnplayr	189
6011	hidnplayr	190	call socket_is_disconnecting
		191	call tcp_usrclosed
4366	hidnplayr	192
		193	test eax, eax
		194	jz @f
		195	push eax
6011	hidnplayr	196	call tcp_output
4366	hidnplayr	197	pop eax
		198	@@:
		199	ret
		200
		201
5976	hidnplayr	202	;-----------------------------------------------------------------;
		203	; ;
6011	hidnplayr	204	; tcp_close ;
5976	hidnplayr	205	; ;
		206	; IN: eax = socket ptr ;
		207	; ;
		208	; OUT: / ;
		209	; ;
		210	;-----------------------------------------------------------------;
3545	hidnplayr	211	align 4
6011	hidnplayr	212	tcp_close:
3545	hidnplayr	213
3556	hidnplayr	214	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_close: %x\n", eax
3545	hidnplayr	215
		216	;;; TODO: update RTT and mean deviation
		217	;;; TODO: update slow start threshold
		218
6011	hidnplayr	219	call socket_is_disconnected
		220	call socket_free
3545	hidnplayr	221
6476	hidnplayr	222	inc [TCPS_closed]
		223
4366	hidnplayr	224	xor eax, eax
3545	hidnplayr	225	ret
		226
		227
		228
5976	hidnplayr	229	;-----------------------------------------------------------------;
		230	; ;
6011	hidnplayr	231	; tcp_outflags ;
5976	hidnplayr	232	; ;
		233	; IN: eax = socket ptr ;
		234	; ;
		235	; OUT: edx = flags ;
		236	; ;
		237	;-----------------------------------------------------------------;
3545	hidnplayr	238	align 4
6011	hidnplayr	239	tcp_outflags:
3545	hidnplayr	240
		241	mov edx, [eax + TCP_SOCKET.t_state]
6011	hidnplayr	242	movzx edx, byte[edx + .flaglist]
3545	hidnplayr	243
3556	hidnplayr	244	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_outflags: socket=%x flags=%x\n", eax, dl
3545	hidnplayr	245
		246	ret
		247
		248	.flaglist:
		249	db TH_RST + TH_ACK ; TCPS_CLOSED
		250	db 0 ; TCPS_LISTEN
		251	db TH_SYN ; TCPS_SYN_SENT
		252	db TH_SYN + TH_ACK ; TCPS_SYN_RECEIVED
		253	db TH_ACK ; TCPS_ESTABLISHED
		254	db TH_ACK ; TCPS_CLOSE_WAIT
		255	db TH_FIN + TH_ACK ; TCPS_FIN_WAIT_1
		256	db TH_FIN + TH_ACK ; TCPS_CLOSING
		257	db TH_FIN + TH_ACK ; TCPS_LAST_ACK
		258	db TH_ACK ; TCPS_FIN_WAIT_2
6476	hidnplayr	259	db TH_ACK ; TCPS_TIME_WAIT
3545	hidnplayr	260
		261
5976	hidnplayr	262	;-----------------------------------------------------------------;
		263	; ;
		264	; TCP_respond: Fast way to send an ACK/RST/keepalive segment. ;
		265	; ;
		266	; IN: ebx = socket ptr ;
		267	; cl = flags ;
		268	; ;
		269	; OUT: / ;
		270	; ;
		271	;-----------------------------------------------------------------;
3545	hidnplayr	272	align 4
6011	hidnplayr	273	tcp_respond:
3545	hidnplayr	274
3556	hidnplayr	275	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: socket=%x flags=%x\n", ebx, cl
3545	hidnplayr	276
		277	;---------------------
		278	; Create the IP packet
		279
		280	push cx ebx
		281	mov edx, [ebx + IP_SOCKET.LocalIP]
5842	hidnplayr	282	mov edi, [ebx + IP_SOCKET.RemoteIP]
		283	mov al, [ebx + IP_SOCKET.ttl]
		284	mov ah, IP_PROTO_TCP
		285	mov ecx, sizeof.TCP_header
5584	hidnplayr	286	mov ebx, [ebx + IP_SOCKET.device]
6011	hidnplayr	287	call ipv4_output
3545	hidnplayr	288	jz .error
		289	pop esi cx
5522	hidnplayr	290	push eax
3545	hidnplayr	291
		292	;-----------------------------------------------
		293	; Fill in the TCP header by using the socket ptr
		294
		295	mov ax, [esi + TCP_SOCKET.LocalPort]
		296	stosw
		297	mov ax, [esi + TCP_SOCKET.RemotePort]
		298	stosw
		299	mov eax, [esi + TCP_SOCKET.SND_NXT]
		300	bswap eax
		301	stosd
		302	mov eax, [esi + TCP_SOCKET.RCV_NXT]
		303	bswap eax
		304	stosd
		305	mov al, 0x50 ; Dataoffset: 20 bytes (TCP_header.DataOffset)
		306	stosb
		307	mov al, cl
		308	stosb
7098	ashmew2	309	mov eax, SOCKET_BUFFER_SIZE
		310	sub eax, [esi + STREAM_SOCKET.rcv.size]
		311	cmp eax, TCP_max_win
		312	jbe .lessthanmax
		313	mov eax, TCP_max_win
		314	.lessthanmax:
		315	mov cl, [esi + TCP_SOCKET.RCV_SCALE]
		316	shr eax, cl
		317
6913	ashmew2	318	xchg al, ah
3545	hidnplayr	319	stosw ; window
		320	xor eax, eax
		321	stosd ; checksum + urgentpointer
		322
		323	;---------------------
		324	; Fill in the checksum
		325
		326	.checksum:
		327	sub edi, sizeof.TCP_header
		328	mov ecx, sizeof.TCP_header
		329	xchg esi, edi
6011	hidnplayr	330	tcp_checksum (edi + IP_SOCKET.LocalIP), (edi + IP_SOCKET.RemoteIP)
3545	hidnplayr	331	mov [esi+TCP_header.Checksum], dx
		332
		333	;--------------------
		334	; And send the segment
		335
		336	call [ebx + NET_DEVICE.transmit]
3644	hidnplayr	337	test eax, eax
		338	jnz @f
6011	hidnplayr	339	call net_ptr_to_num4
3644	hidnplayr	340	inc [TCP_segments_tx + edi]
		341	@@:
3545	hidnplayr	342	ret
		343
		344	.error:
3556	hidnplayr	345	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: failed\n"
3545	hidnplayr	346	add esp, 2 + 4
		347
		348	ret
		349
		350
5976	hidnplayr	351	;-----------------------------------------------------------------;
		352	; ;
6011	hidnplayr	353	; tcp_respond_segment ;
5976	hidnplayr	354	; ;
		355	; IN: ebx = device ptr ;
		356	; edx = segment ptr (a previously received segment) ;
		357	; edi = ptr to IPv4 header ;
		358	; cl = flags ;
		359	; ;
		360	; OUT: / ;
		361	; ;
		362	;-----------------------------------------------------------------;
3545	hidnplayr	363	align 4
6011	hidnplayr	364	tcp_respond_segment:
3545	hidnplayr	365
5842	hidnplayr	366	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: frame=%x flags=%x\n", edx, cl
3545	hidnplayr	367
		368	;---------------------
		369	; Create the IP packet
		370
		371	push cx edx
5842	hidnplayr	372	mov edx, [edi + IPv4_header.DestinationAddress]
		373	mov edi, [edi + IPv4_header.SourceAddress]
3545	hidnplayr	374	mov ecx, sizeof.TCP_header
5842	hidnplayr	375	mov ax, IP_PROTO_TCP shl 8 + 128
6011	hidnplayr	376	call ipv4_output
3545	hidnplayr	377	jz .error
		378	pop esi cx
		379
5522	hidnplayr	380	push eax
3545	hidnplayr	381
		382	;---------------------------------------------------
		383	; Fill in the TCP header by using a received segment
		384
		385	mov ax, [esi + TCP_header.DestinationPort]
		386	stosw
		387	mov ax, [esi + TCP_header.SourcePort]
		388	stosw
		389	mov eax, [esi + TCP_header.AckNumber]
		390	bswap eax
		391	stosd
		392	xor eax, eax
		393	stosd
		394	mov al, 0x50 ; Dataoffset: 20 bytes (sizeof.TCP_header/4 shl 4)
		395	stosb
		396	mov al, cl
		397	stosb
		398	mov ax, 1280
		399	rol ax, 8
		400	stosw ; window
		401	xor eax, eax
		402	stosd ; checksum + urgentpointer
		403
		404	;---------------------
		405	; Fill in the checksum
		406
		407	lea esi, [edi - sizeof.TCP_header]
		408	mov ecx, sizeof.TCP_header
6011	hidnplayr	409	tcp_checksum (esi - sizeof.IPv4_header + IPv4_header.DestinationAddress),\ ; FIXME
3545	hidnplayr	410	(esi - sizeof.IPv4_header + IPv4_header.SourceAddress)
		411	mov [esi + TCP_header.Checksum], dx
		412
		413	;--------------------
		414	; And send the segment
		415
		416	call [ebx + NET_DEVICE.transmit]
3644	hidnplayr	417	test eax, eax
		418	jnz @f
6011	hidnplayr	419	call net_ptr_to_num4
3644	hidnplayr	420	inc [TCP_segments_tx + edi]
		421	@@:
3545	hidnplayr	422	ret
		423
		424	.error:
3556	hidnplayr	425	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: failed\n"
3545	hidnplayr	426	add esp, 2+4
		427
		428	ret
		429
		430
6011	hidnplayr	431	macro tcpt_rangeset timer, value, min, max {
3545	hidnplayr	432
		433	local .min
		434	local .max
		435	local .done
		436
		437	cmp value, min
		438	jb .min
		439	cmp value, max
		440	ja .max
		441	mov timer, value
		442	jmp .done
		443	.min:
6512	hidnplayr	444	mov timer, min
3545	hidnplayr	445	jmp .done
		446	.max:
6512	hidnplayr	447	mov timer, max
3545	hidnplayr	448	.done:
		449	}
		450
5976	hidnplayr	451	;-----------------------------------------------------------------;
		452	; ;
6011	hidnplayr	453	; tcp_set_persist ;
5976	hidnplayr	454	; ;
		455	;-----------------------------------------------------------------;
3545	hidnplayr	456	align 4
6011	hidnplayr	457	tcp_set_persist:
3545	hidnplayr	458
3556	hidnplayr	459	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_set_persist\n"
3545	hidnplayr	460
		461	; First, check if retransmit timer is not set, retransmit and persist are mutually exclusive
		462
3600	hidnplayr	463	test [eax + TCP_SOCKET.timer_flags], timer_flag_retransmission
		464	jnz .exit
3545	hidnplayr	465
		466	; calculate RTO
		467	push ebx
		468	mov ebx, [eax + TCP_SOCKET.t_srtt]
		469	shr ebx, 2
		470	add ebx, [eax + TCP_SOCKET.t_rttvar]
		471	shr ebx, 1
		472
		473	mov cl, [eax + TCP_SOCKET.t_rxtshift]
		474	shl ebx, cl
		475
		476	; Start/restart persistance timer.
		477
6011	hidnplayr	478	tcpt_rangeset [eax + TCP_SOCKET.timer_persist], ebx, TCP_time_pers_min, TCP_time_pers_max
3600	hidnplayr	479	or [ebx + TCP_SOCKET.timer_flags], timer_flag_persist
3545	hidnplayr	480	pop ebx
		481
		482	cmp [eax + TCP_SOCKET.t_rxtshift], TCP_max_rxtshift
		483	jae @f
		484	inc [eax + TCP_SOCKET.t_rxtshift]
		485	@@:
3600	hidnplayr	486	.exit:
3545	hidnplayr	487
		488	ret
		489
		490
		491
5976	hidnplayr	492	;-----------------------------------------------------------------;
		493	; ;
6011	hidnplayr	494	; tcp_xmit_timer: Calculate new smoothed RTT. ;
5976	hidnplayr	495	; ;
		496	; IN: eax = rtt ;
		497	; ebx = socket ptr ;
		498	; ;
		499	; OUT: / ;
		500	; ;
		501	;-----------------------------------------------------------------;
3545	hidnplayr	502	align 4
6011	hidnplayr	503	tcp_xmit_timer:
3545	hidnplayr	504
5976	hidnplayr	505	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_xmit_timer: socket=0x%x rtt=%d0ms\n", ebx, eax
3545	hidnplayr	506
6476	hidnplayr	507	inc [TCPS_rttupdated]
3545	hidnplayr	508
		509	cmp [ebx + TCP_SOCKET.t_rtt], 0
		510	je .no_rtt_yet
		511
		512	; srtt is stored as a fixed point with 3 bits after the binary point.
		513	; The following magic is equivalent of the smoothing algorithm in rfc793 with an alpha of .875
		514	; (srtt = rtt/8 + srtt*7/8 in fixed point)
		515	; Adjust rtt to origin 0.
		516
		517	push ecx
		518	mov ecx, [ebx + TCP_SOCKET.t_srtt]
		519	shr ecx, TCP_RTT_SHIFT
		520	sub eax, ecx
		521	dec eax
		522	pop ecx
		523
		524	add [ebx + TCP_SOCKET.t_srtt], eax
		525	ja @f
		526	mov [ebx + TCP_SOCKET.t_srtt], 1
		527	@@:
		528
		529	; We accumulate a smoothed rtt variance (actually, a smoothed mean difference),
		530	; then set the retransmit timer to smoothed rtt + 4 times the smoothed variance.
		531	; rttvar is stored as fixed point with 2 bits after the binary point.
		532	; The following is equivalent to rfc793 smoothing with an alpha of .75
		533	; (rttvar = rttvar*3/4 + delta/4) (delta = eax)
		534
		535	; get abs(eax)
		536	push edx
		537	cdq
		538	xor eax, edx
		539	sub eax, edx
		540
		541	mov edx, [ebx + TCP_SOCKET.t_rttvar]
		542	shr edx, TCP_RTTVAR_SHIFT
		543	sub eax, edx
		544	pop edx
		545
		546	add [ebx + TCP_SOCKET.t_rttvar], eax
		547	ja @f
		548	mov [ebx + TCP_SOCKET.t_rttvar], 1
		549	@@:
		550	ret
		551
		552
		553	.no_rtt_yet:
		554	push ecx
		555	mov ecx, eax
		556	shl ecx, TCP_RTT_SHIFT
		557	mov [ebx + TCP_SOCKET.t_srtt], ecx
		558
		559	shl eax, TCP_RTTVAR_SHIFT - 1
		560	mov [ebx + TCP_SOCKET.t_rttvar], eax
		561	pop ecx
		562
		563	ret
		564
		565
5976	hidnplayr	566	;-----------------------------------------------------------------;
		567	; ;
6011	hidnplayr	568	; tcp_mss: Update maximum segment size ;
5976	hidnplayr	569	; ;
		570	; IN: eax = max segment size ;
		571	; ebx = socket ptr ;
		572	; ;
		573	; OUT: / ;
		574	; ;
		575	;-----------------------------------------------------------------;
3545	hidnplayr	576	align 4
6011	hidnplayr	577	tcp_mss:
3545	hidnplayr	578
5976	hidnplayr	579	cmp eax, 1420 ; FIXME
3545	hidnplayr	580	jbe @f
		581	mov eax, 1420
		582	@@:
		583	mov [ebx + TCP_SOCKET.t_maxseg], eax
		584
		585
		586	ret
		587
		588
		589
5976	hidnplayr	590	;-----------------------------------------------------------------;
		591	; ;
6011	hidnplayr	592	; tcp_reassemble ;
5976	hidnplayr	593	; ;
		594	; IN: ebx = socket ptr ;
		595	; edx = segment ptr ;
		596	; ;
		597	; OUT: / ;
		598	; ;
		599	;-----------------------------------------------------------------;
3545	hidnplayr	600	align 4
6011	hidnplayr	601	tcp_reassemble:
3545	hidnplayr	602
5976	hidnplayr	603	;;;;; TODO
3545	hidnplayr	604
		605	ret
		606

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(root)/kernel/trunk/network/tcp_subr.inc – Rev 7974