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: 6913 $
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
6913	ashmew2	306	mov eax, [esi + TCP_SOCKET.RCV_WND]
		307	xchg al, ah
3545	hidnplayr	308	stosw ; window
		309	xor eax, eax
		310	stosd ; checksum + urgentpointer
		311
		312	;---------------------
		313	; Fill in the checksum
		314
		315	.checksum:
		316	sub edi, sizeof.TCP_header
		317	mov ecx, sizeof.TCP_header
		318	xchg esi, edi
6011	hidnplayr	319	tcp_checksum (edi + IP_SOCKET.LocalIP), (edi + IP_SOCKET.RemoteIP)
3545	hidnplayr	320	mov [esi+TCP_header.Checksum], dx
		321
		322	;--------------------
		323	; And send the segment
		324
		325	call [ebx + NET_DEVICE.transmit]
3644	hidnplayr	326	test eax, eax
		327	jnz @f
6011	hidnplayr	328	call net_ptr_to_num4
3644	hidnplayr	329	inc [TCP_segments_tx + edi]
		330	@@:
3545	hidnplayr	331	ret
		332
		333	.error:
3556	hidnplayr	334	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: failed\n"
3545	hidnplayr	335	add esp, 2 + 4
		336
		337	ret
		338
		339
5976	hidnplayr	340	;-----------------------------------------------------------------;
		341	; ;
6011	hidnplayr	342	; tcp_respond_segment ;
5976	hidnplayr	343	; ;
		344	; IN: ebx = device ptr ;
		345	; edx = segment ptr (a previously received segment) ;
		346	; edi = ptr to IPv4 header ;
		347	; cl = flags ;
		348	; ;
		349	; OUT: / ;
		350	; ;
		351	;-----------------------------------------------------------------;
3545	hidnplayr	352	align 4
6011	hidnplayr	353	tcp_respond_segment:
3545	hidnplayr	354
5842	hidnplayr	355	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: frame=%x flags=%x\n", edx, cl
3545	hidnplayr	356
		357	;---------------------
		358	; Create the IP packet
		359
		360	push cx edx
5842	hidnplayr	361	mov edx, [edi + IPv4_header.DestinationAddress]
		362	mov edi, [edi + IPv4_header.SourceAddress]
3545	hidnplayr	363	mov ecx, sizeof.TCP_header
5842	hidnplayr	364	mov ax, IP_PROTO_TCP shl 8 + 128
6011	hidnplayr	365	call ipv4_output
3545	hidnplayr	366	jz .error
		367	pop esi cx
		368
5522	hidnplayr	369	push eax
3545	hidnplayr	370
		371	;---------------------------------------------------
		372	; Fill in the TCP header by using a received segment
		373
		374	mov ax, [esi + TCP_header.DestinationPort]
		375	stosw
		376	mov ax, [esi + TCP_header.SourcePort]
		377	stosw
		378	mov eax, [esi + TCP_header.AckNumber]
		379	bswap eax
		380	stosd
		381	xor eax, eax
		382	stosd
		383	mov al, 0x50 ; Dataoffset: 20 bytes (sizeof.TCP_header/4 shl 4)
		384	stosb
		385	mov al, cl
		386	stosb
		387	mov ax, 1280
		388	rol ax, 8
		389	stosw ; window
		390	xor eax, eax
		391	stosd ; checksum + urgentpointer
		392
		393	;---------------------
		394	; Fill in the checksum
		395
		396	lea esi, [edi - sizeof.TCP_header]
		397	mov ecx, sizeof.TCP_header
6011	hidnplayr	398	tcp_checksum (esi - sizeof.IPv4_header + IPv4_header.DestinationAddress),\ ; FIXME
3545	hidnplayr	399	(esi - sizeof.IPv4_header + IPv4_header.SourceAddress)
		400	mov [esi + TCP_header.Checksum], dx
		401
		402	;--------------------
		403	; And send the segment
		404
		405	call [ebx + NET_DEVICE.transmit]
3644	hidnplayr	406	test eax, eax
		407	jnz @f
6011	hidnplayr	408	call net_ptr_to_num4
3644	hidnplayr	409	inc [TCP_segments_tx + edi]
		410	@@:
3545	hidnplayr	411	ret
		412
		413	.error:
3556	hidnplayr	414	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: failed\n"
3545	hidnplayr	415	add esp, 2+4
		416
		417	ret
		418
		419
6011	hidnplayr	420	macro tcpt_rangeset timer, value, min, max {
3545	hidnplayr	421
		422	local .min
		423	local .max
		424	local .done
		425
		426	cmp value, min
		427	jb .min
		428	cmp value, max
		429	ja .max
		430	mov timer, value
		431	jmp .done
		432	.min:
6512	hidnplayr	433	mov timer, min
3545	hidnplayr	434	jmp .done
		435	.max:
6512	hidnplayr	436	mov timer, max
3545	hidnplayr	437	.done:
		438	}
		439
5976	hidnplayr	440	;-----------------------------------------------------------------;
		441	; ;
6011	hidnplayr	442	; tcp_set_persist ;
5976	hidnplayr	443	; ;
		444	;-----------------------------------------------------------------;
3545	hidnplayr	445	align 4
6011	hidnplayr	446	tcp_set_persist:
3545	hidnplayr	447
3556	hidnplayr	448	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_set_persist\n"
3545	hidnplayr	449
		450	; First, check if retransmit timer is not set, retransmit and persist are mutually exclusive
		451
3600	hidnplayr	452	test [eax + TCP_SOCKET.timer_flags], timer_flag_retransmission
		453	jnz .exit
3545	hidnplayr	454
		455	; calculate RTO
		456	push ebx
		457	mov ebx, [eax + TCP_SOCKET.t_srtt]
		458	shr ebx, 2
		459	add ebx, [eax + TCP_SOCKET.t_rttvar]
		460	shr ebx, 1
		461
		462	mov cl, [eax + TCP_SOCKET.t_rxtshift]
		463	shl ebx, cl
		464
		465	; Start/restart persistance timer.
		466
6011	hidnplayr	467	tcpt_rangeset [eax + TCP_SOCKET.timer_persist], ebx, TCP_time_pers_min, TCP_time_pers_max
3600	hidnplayr	468	or [ebx + TCP_SOCKET.timer_flags], timer_flag_persist
3545	hidnplayr	469	pop ebx
		470
		471	cmp [eax + TCP_SOCKET.t_rxtshift], TCP_max_rxtshift
		472	jae @f
		473	inc [eax + TCP_SOCKET.t_rxtshift]
		474	@@:
3600	hidnplayr	475	.exit:
3545	hidnplayr	476
		477	ret
		478
		479
		480
5976	hidnplayr	481	;-----------------------------------------------------------------;
		482	; ;
6011	hidnplayr	483	; tcp_xmit_timer: Calculate new smoothed RTT. ;
5976	hidnplayr	484	; ;
		485	; IN: eax = rtt ;
		486	; ebx = socket ptr ;
		487	; ;
		488	; OUT: / ;
		489	; ;
		490	;-----------------------------------------------------------------;
3545	hidnplayr	491	align 4
6011	hidnplayr	492	tcp_xmit_timer:
3545	hidnplayr	493
5976	hidnplayr	494	DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_xmit_timer: socket=0x%x rtt=%d0ms\n", ebx, eax
3545	hidnplayr	495
6476	hidnplayr	496	inc [TCPS_rttupdated]
3545	hidnplayr	497
		498	cmp [ebx + TCP_SOCKET.t_rtt], 0
		499	je .no_rtt_yet
		500
		501	; srtt is stored as a fixed point with 3 bits after the binary point.
		502	; The following magic is equivalent of the smoothing algorithm in rfc793 with an alpha of .875
		503	; (srtt = rtt/8 + srtt*7/8 in fixed point)
		504	; Adjust rtt to origin 0.
		505
		506	push ecx
		507	mov ecx, [ebx + TCP_SOCKET.t_srtt]
		508	shr ecx, TCP_RTT_SHIFT
		509	sub eax, ecx
		510	dec eax
		511	pop ecx
		512
		513	add [ebx + TCP_SOCKET.t_srtt], eax
		514	ja @f
		515	mov [ebx + TCP_SOCKET.t_srtt], 1
		516	@@:
		517
		518	; We accumulate a smoothed rtt variance (actually, a smoothed mean difference),
		519	; then set the retransmit timer to smoothed rtt + 4 times the smoothed variance.
		520	; rttvar is stored as fixed point with 2 bits after the binary point.
		521	; The following is equivalent to rfc793 smoothing with an alpha of .75
		522	; (rttvar = rttvar*3/4 + delta/4) (delta = eax)
		523
		524	; get abs(eax)
		525	push edx
		526	cdq
		527	xor eax, edx
		528	sub eax, edx
		529
		530	mov edx, [ebx + TCP_SOCKET.t_rttvar]
		531	shr edx, TCP_RTTVAR_SHIFT
		532	sub eax, edx
		533	pop edx
		534
		535	add [ebx + TCP_SOCKET.t_rttvar], eax
		536	ja @f
		537	mov [ebx + TCP_SOCKET.t_rttvar], 1
		538	@@:
		539	ret
		540
		541
		542	.no_rtt_yet:
		543	push ecx
		544	mov ecx, eax
		545	shl ecx, TCP_RTT_SHIFT
		546	mov [ebx + TCP_SOCKET.t_srtt], ecx
		547
		548	shl eax, TCP_RTTVAR_SHIFT - 1
		549	mov [ebx + TCP_SOCKET.t_rttvar], eax
		550	pop ecx
		551
		552	ret
		553
		554
5976	hidnplayr	555	;-----------------------------------------------------------------;
		556	; ;
6011	hidnplayr	557	; tcp_mss: Update maximum segment size ;
5976	hidnplayr	558	; ;
		559	; IN: eax = max segment size ;
		560	; ebx = socket ptr ;
		561	; ;
		562	; OUT: / ;
		563	; ;
		564	;-----------------------------------------------------------------;
3545	hidnplayr	565	align 4
6011	hidnplayr	566	tcp_mss:
3545	hidnplayr	567
5976	hidnplayr	568	cmp eax, 1420 ; FIXME
3545	hidnplayr	569	jbe @f
		570	mov eax, 1420
		571	@@:
		572	mov [ebx + TCP_SOCKET.t_maxseg], eax
		573
		574
		575	ret
		576
		577
		578
5976	hidnplayr	579	;-----------------------------------------------------------------;
		580	; ;
6011	hidnplayr	581	; tcp_reassemble ;
5976	hidnplayr	582	; ;
		583	; IN: ebx = socket ptr ;
		584	; edx = segment ptr ;
		585	; ;
		586	; OUT: / ;
		587	; ;
		588	;-----------------------------------------------------------------;
3545	hidnplayr	589	align 4
6011	hidnplayr	590	tcp_reassemble:
3545	hidnplayr	591
5976	hidnplayr	592	;;;;; TODO
3545	hidnplayr	593
		594	ret
		595

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(root)/kernel/trunk/network/tcp_subr.inc – Rev 6913