WebSVN – Kolibri OS – Blame – /kernel/branches/net/network/tcp_input.inc

Rev	Author	Line No.	Line
1763	hidnplayr	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
		3	;; Copyright (C) KolibriOS team 2004-2011. All rights reserved. ;;
		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
		17	$Revision: 2305 $
		18
1733	hidnplayr	19	;-----------------------------------------------------------------
		20	;
		21	; TCP_input:
		22	;
		23	; IN: [esp] = ptr to buffer
		24	; [esp+4] = buffer size
		25	; ebx = ptr to device struct
		26	; ecx = segment size
		27	; edx = ptr to TCP segment
		28	;
		29	; esi = ipv4 source address
		30	; edi = ipv4 dest address
		31	;
		32	; OUT: /
		33	;
		34	;-----------------------------------------------------------------
1830	hidnplayr	35
1733	hidnplayr	36	align 4
		37	TCP_input:
		38
		39	DEBUGF 1,"TCP_input size=%u ", ecx
		40	; Offset must be greater than or equal to the size of the standard TCP header (20) and less than or equal to the TCP length.
		41
2305	hidnplayr	42	movzx eax, [edx + TCP_header.DataOffset]
1733	hidnplayr	43	and eax, 0xf0
		44	shr al, 2
		45
		46	DEBUGF 1,"headersize=%u\n", eax
		47
2305	hidnplayr	48	cmp eax, TCP_header.DataOffset
2300	hidnplayr	49	jb .drop_not_locked
1733	hidnplayr	50
		51	;-------------------------------
		52	; Now, re-calculate the checksum
		53
		54	push eax ecx edx
2305	hidnplayr	55	pushw [edx + TCP_header.Checksum]
		56	mov [edx + TCP_header.Checksum], 0
1733	hidnplayr	57	push esi edi
		58	mov esi, edx
		59	TCP_checksum (esp), (esp+4)
		60	pop esi edi ; yes, swap them (we dont need dest addr)
		61	pop cx ; previous checksum
		62	cmp cx, dx
		63	pop edx ecx esi
		64	jnz .drop_not_locked
		65
		66	DEBUGF 1,"Checksum is correct\n"
		67
		68	sub ecx, esi ; update packet size
2300	hidnplayr	69	jb .drop_not_locked
1733	hidnplayr	70	DEBUGF 1,"we got %u bytes of data\n", ecx
		71
		72	;-----------------------------------------------------------------------------------------
		73	; Check if this packet has a timestamp option (We do it here so we can process it quickly)
		74
2305	hidnplayr	75	cmp esi, TCP_header.DataOffset + 12 ; Timestamp option is 12 bytes
2300	hidnplayr	76	jb .no_timestamp
1733	hidnplayr	77	je .is_ok
		78
2305	hidnplayr	79	cmp byte [edx + sizeof.TCP_header + 12], TCP_OPT_EOL ; end of option list
1733	hidnplayr	80	jne .no_timestamp
		81
		82	.is_ok:
2305	hidnplayr	83	test [edx + TCP_header.Flags], TH_SYN ; SYN flag must not be set
1733	hidnplayr	84	jnz .no_timestamp
		85
2305	hidnplayr	86	cmp dword [edx + sizeof.TCP_header], 0x0101080a ; Timestamp header
1733	hidnplayr	87	jne .no_timestamp
		88
		89	DEBUGF 1,"timestamp ok\n"
		90
		91	; TODO: Parse the option
		92	; TODO: Set a Bit in the TCP to tell all options are parsed
		93
		94	.no_timestamp:
		95
		96	;-------------------------------------------
		97	; Convert Big-endian values to little endian
		98
2305	hidnplayr	99	ntohd [edx + TCP_header.SequenceNumber]
		100	ntohd [edx + TCP_header.AckNumber]
1733	hidnplayr	101
2305	hidnplayr	102	ntohw [edx + TCP_header.Window]
		103	ntohw [edx + TCP_header.UrgentPointer]
		104	ntohw [edx + TCP_header.SourcePort]
		105	ntohw [edx + TCP_header.DestinationPort]
1733	hidnplayr	106
		107	;------------------------------------------------------------
1831	hidnplayr	108	; Next thing to do is find the TCPS (thus, the socket pointer)
1733	hidnplayr	109
		110	; IP Packet TCP Destination Port = local Port
		111	; (IP Packet SenderAddress = Remote IP) OR (Remote IP = 0)
		112	; (IP Packet TCP Source Port = remote Port) OR (remote Port = 0)
		113
		114	mov ebx, net_sockets
		115
		116	.socket_loop:
		117	mov ebx, [ebx + SOCKET.NextPtr]
		118	or ebx, ebx
		119	jz .drop_with_reset_not_locked
		120
		121	cmp [ebx + SOCKET.Domain], AF_INET4
		122	jne .socket_loop
		123
		124	cmp [ebx + SOCKET.Protocol], IP_PROTO_TCP
		125	jne .socket_loop
		126
2305	hidnplayr	127	mov ax, [edx + TCP_header.DestinationPort]
1733	hidnplayr	128	cmp [ebx + TCP_SOCKET.LocalPort], ax
		129	jne .socket_loop
		130
		131	mov eax, [ebx + IP_SOCKET.RemoteIP]
		132	cmp eax, edi ; edi is source ip from packet
		133	je @f
		134	test eax, eax
		135	jnz .socket_loop
		136	@@:
		137
		138	mov ax, [ebx + TCP_SOCKET.RemotePort]
2305	hidnplayr	139	cmp [edx + TCP_header.SourcePort] , ax
1733	hidnplayr	140	je .found_socket
		141	test ax, ax
		142	jnz .socket_loop
		143	.found_socket:
		144	DEBUGF 1,"Socket ptr: %x\n", ebx
		145
		146	; ebx now contains the pointer to the socket
		147
		148	;----------------------------
		149	; Check if socket isnt closed
		150
1831	hidnplayr	151	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSED
1733	hidnplayr	152	je .drop_not_locked
		153
		154	;----------------
		155	; Lock the socket
		156
1830	hidnplayr	157	cmp [ebx + SOCKET.lock], 0
		158	jne .drop_not_locked ;;; HACK ! HACK ! dirty fucking HACK ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
		159
1733	hidnplayr	160	add ebx, SOCKET.lock
		161	DEBUGF 1,"lock: %x\n", [ebx]
		162	call wait_mutex
		163	sub ebx, SOCKET.lock
		164
1830	hidnplayr	165
1733	hidnplayr	166	DEBUGF 1,"Socket locked\n"
		167
		168	;---------------------------------------
		169	; unscale the window into a 32 bit value
		170
2305	hidnplayr	171	movzx eax, [edx + TCP_header.Window]
1733	hidnplayr	172	push ecx
		173	mov cl, [ebx + TCP_SOCKET.SND_SCALE]
		174	shl eax, cl
2305	hidnplayr	175	mov dword [edx + TCP_header.Window], eax ; word after window is checksum, we dont need checksum anymore
1733	hidnplayr	176	pop ecx
		177
		178	;-----------------------------------
		179	; Is this socket a listening socket?
		180
		181	test [ebx + SOCKET.options], SO_ACCEPTCON
		182	jz .no_listening_socket
		183
1838	hidnplayr	184	DEBUGF 1,"Accepting new connection\n"
		185
		186	mov [ebx + SOCKET.lock], 0
1733	hidnplayr	187	call SOCKET_fork
1838	hidnplayr	188
		189	test eax, eax
1733	hidnplayr	190	jz .drop
		191
2305	hidnplayr	192	push [edx - sizeof.IPv4_header + IPv4_header.DestinationAddress] ;;; FIXME
1733	hidnplayr	193	pop [eax + IP_SOCKET.LocalIP]
		194
2305	hidnplayr	195	push [edx + TCP_header.DestinationPort]
1838	hidnplayr	196	pop [eax + TCP_SOCKET.LocalPort]
1733	hidnplayr	197
1831	hidnplayr	198	mov [eax + TCP_SOCKET.t_state], TCPS_LISTEN
1733	hidnplayr	199
1838	hidnplayr	200	; mov [ebx + SOCKET.lock], 0
		201	mov ebx, eax
1733	hidnplayr	202
1838	hidnplayr	203	jmp .LISTEN
		204
1733	hidnplayr	205	.no_listening_socket:
		206
		207	;-------------------------------------
		208	; Reset idle timer and keepalive timer
		209
		210	mov [ebx + TCP_SOCKET.t_idle], 0
		211	mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval
		212
		213	;--------------------
		214	; Process TCP options
		215
2305	hidnplayr	216	cmp esi, TCP_header.DataOffset ; esi is headersize
1733	hidnplayr	217	je .no_options
		218
		219	DEBUGF 1,"Segment has options\n"
		220
2301	hidnplayr	221	cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN ; no options when in listen state
		222	jz .not_uni_xfer ; also no header prediction
1733	hidnplayr	223
2305	hidnplayr	224	lea edi, [edx + sizeof.TCP_header]
1733	hidnplayr	225	lea eax, [edx + esi]
		226
		227	.opt_loop:
		228	cmp edi, eax
2300	hidnplayr	229	jae .no_options
1733	hidnplayr	230
		231	cmp byte [edi], TCP_OPT_EOL ; end of option list?
		232	jz .no_options
		233
		234	cmp byte [edi], TCP_OPT_NOP ; nop ?
		235	jz .opt_nop
		236
		237	cmp byte [edi], TCP_OPT_MAXSEG
		238	je .opt_maxseg
		239
		240	cmp byte [edi], TCP_OPT_WINDOW
		241	je .opt_window
		242
		243	cmp byte [edi], TCP_OPT_TIMESTAMP
		244	je .opt_timestamp
		245
		246	jmp .no_options ; If we reach here, some unknown options were received, skip them all!
		247
		248	.opt_nop:
		249	inc edi
		250	jmp .opt_loop
		251
		252	.opt_maxseg:
		253	cmp byte [edi+1], 4
		254	jne .no_options ; error occured, ignore all options!
		255
2305	hidnplayr	256	test [edx + TCP_header.Flags], TH_SYN
1733	hidnplayr	257	jz @f
		258
		259	movzx eax, word[edi+2]
		260	rol ax, 8
		261	DEBUGF 1,"Maxseg: %u\n", ax
		262
		263	mov [ebx + TCP_SOCKET.t_maxseg], eax
		264
		265	@@:
		266	add edi, 4
		267	jmp .opt_loop
		268
		269
		270	.opt_window:
		271	cmp byte [edi+1], 3
		272	jne .no_options
		273
2305	hidnplayr	274	test [edx + TCP_header.Flags], TH_SYN
1733	hidnplayr	275	jz @f
		276
		277	DEBUGF 1,"Got window option\n"
		278
		279	;;;;;
		280	@@:
		281	add edi, 3
		282	jmp .opt_loop
		283
		284
		285	.opt_timestamp:
		286	cmp byte [edi+1], 10
		287	jne .no_options
		288
		289	DEBUGF 1,"Got timestamp option\n"
		290
		291	;;;;;
		292
		293	add edi, 10
		294	jmp .opt_loop
		295
		296	.no_options:
		297
		298
		299
		300
		301
		302
		303	;-----------------------------------------------------------------------
		304	; Time to do some header prediction (Original Principle by Van Jacobson)
		305
		306	; There are two common cases for an uni-directional data transfer.
		307	;
		308	; General rule: the packets has no control flags, is in-sequence,
		309	; window width didnt change and we're not retransmitting.
		310	;
		311	; Second rules:
		312	; - If the length is 0 and the ACK moved forward, we're the sender side of the transfer.
		313	; In this case we'll free the ACK'ed data and notify higher levels that we have free space in buffer
		314	;
		315	; - If the length is not 0 and the ACK didn't move, we're the receiver side of the transfer.
		316	; If the packets are in order (data queue is empty), add the data to the socket buffer and request a delayed ACK
		317
1831	hidnplayr	318	cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED
1733	hidnplayr	319	jnz .not_uni_xfer
		320
2305	hidnplayr	321	test [edx + TCP_header.Flags], TH_SYN + TH_FIN + TH_RST + TH_URG
1733	hidnplayr	322	jnz .not_uni_xfer
		323
2305	hidnplayr	324	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	325	jz .not_uni_xfer
		326
2305	hidnplayr	327	mov eax, [edx + TCP_header.SequenceNumber]
1733	hidnplayr	328	cmp eax, [ebx + TCP_SOCKET.RCV_NXT]
		329	jne .not_uni_xfer
		330
2305	hidnplayr	331	mov eax, dword [edx + TCP_header.Window]
1733	hidnplayr	332	cmp eax, [ebx + TCP_SOCKET.SND_WND]
		333	jne .not_uni_xfer
		334
		335	mov eax, [ebx + TCP_SOCKET.SND_NXT]
		336	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
		337	jne .not_uni_xfer
		338
		339	;---------------------------------------
		340	; check if we are sender in the uni-xfer
		341
		342	; If the following 4 conditions are all true, this segment is a pure ACK.
		343	;
		344	; - The segment contains no data.
		345	test ecx, ecx
		346	jnz .not_sender
		347
		348	; - The congestion window is greater than or equal to the current send window.
		349	; This test is true only if the window is fully open, that is, the connection is not in the middle of slow start or congestion avoidance.
		350	mov eax, [ebx + TCP_SOCKET.SND_CWND]
		351	cmp eax, [ebx + TCP_SOCKET.SND_WND]
2300	hidnplayr	352	jb .not_uni_xfer
1733	hidnplayr	353
		354	; - The acknowledgment field in the segment is less than or equal to the maximum sequence number sent.
2305	hidnplayr	355	mov eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	356	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
2300	hidnplayr	357	ja .not_uni_xfer
1733	hidnplayr	358
		359	; - The acknowledgment field in the segment is greater than the largest unacknowledged sequence number.
		360	sub eax, [ebx + TCP_SOCKET.SND_UNA]
2300	hidnplayr	361	jbe .not_uni_xfer
1733	hidnplayr	362
		363	DEBUGF 1,"Header prediction: we are sender\n"
		364
		365	;---------------------------------
		366	; Packet is a pure ACK, process it
		367
		368	; Update RTT estimators
		369
1763	hidnplayr	370	;;; TODO
		371
1733	hidnplayr	372	; Delete acknowledged bytes from send buffer
		373	pusha
		374	mov ecx, eax
		375	lea eax, [ebx + STREAM_SOCKET.snd]
		376	call SOCKET_ring_free
		377	popa
		378
		379	; update window pointers
2305	hidnplayr	380	mov eax, [edx + TCP_header.AckNumber]
1763	hidnplayr	381	mov [ebx + TCP_SOCKET.SND_UNA], eax
1733	hidnplayr	382
		383	; Stop retransmit timer
1830	hidnplayr	384	mov [ebx + TCP_SOCKET.timer_retransmission], 0
1733	hidnplayr	385
		386	; Awaken waiting processes
1763	hidnplayr	387	mov [ebx + SOCKET.lock], 0
1733	hidnplayr	388	mov eax, ebx
		389	call SOCKET_notify_owner
		390
1763	hidnplayr	391	; Generate more output
		392	call TCP_output
1733	hidnplayr	393
1763	hidnplayr	394	jmp .drop_not_locked
		395
1733	hidnplayr	396	;-------------------------------------------------
		397	; maybe we are the receiver in the uni-xfer then..
		398
		399	.not_sender:
		400	; - The amount of data in the segment is greater than 0 (data count is in ecx)
		401
		402	; - The acknowledgment field equals the largest unacknowledged sequence number. This means no data is acknowledged by this segment.
2305	hidnplayr	403	mov eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	404	cmp eax, [ebx + TCP_SOCKET.SND_UNA]
		405	jne .not_uni_xfer
		406
		407	; - The reassembly list of out-of-order segments for the connection is empty (seg_next equals tp).
		408
		409	;;; TODO
		410
		411	jnz .not_uni_xfer
		412
		413	; Complete processing of received data
		414
		415	DEBUGF 1,"header prediction: we are receiver\nreceiving %u bytes of data\n", ecx
		416
1763	hidnplayr	417	add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied
		418
1733	hidnplayr	419	add esi, edx
		420	lea eax, [ebx + STREAM_SOCKET.rcv]
		421	call SOCKET_ring_write ; Add the data to the socket buffer
		422
		423	mov eax, ebx
		424	call SOCKET_notify_owner
		425
		426	or [ebx + TCP_SOCKET.t_flags], TF_DELACK ; Set delayed ack flag
		427
		428	jmp .drop
		429
		430
		431
		432
		433
		434
		435	;--------------------------------------------------
		436	; Header prediction failed, do it the slow way
		437
		438	.not_uni_xfer:
		439
		440	DEBUGF 1,"Header prediction failed\n"
		441
		442	; Calculate receive window size
		443
2305	hidnplayr	444	; mov eax, [ebx + STREAM_SOCKET.rcv + RING_BUFFER.size]
		445	; neg eax
		446	; add eax, SOCKETBUFFSIZE
		447	; mov edx, [ebx + TCP_SOCKET.RCV_ADV]
		448	; sub edx, [ebx + TCP_SOCKET.RCV_NXT]
		449	; cmp eax, edx
		450	; jae @f
		451	; mov eax, edx
		452	; @@:
1733	hidnplayr	453
1831	hidnplayr	454	cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN
1733	hidnplayr	455	je .LISTEN
		456
1831	hidnplayr	457	cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_SENT
1733	hidnplayr	458	je .SYN_SENT
		459
		460	jmp .NOT_LISTEN_OR_SYN_SENT
		461
		462
		463
		464	;-------------
		465	; Passive Open
		466
		467	align 4
		468	.LISTEN:
		469
		470	DEBUGF 1,"TCP state: listen\n"
		471
2305	hidnplayr	472	test [edx + TCP_header.Flags], TH_RST ;;; TODO: kill new socket on error
1733	hidnplayr	473	jnz .drop
		474
2305	hidnplayr	475	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	476	jnz .drop_with_reset
		477
2305	hidnplayr	478	test [edx + TCP_header.Flags], TH_SYN
1733	hidnplayr	479	jz .drop
		480
		481	;;; TODO: check if it's a broadcast or multicast, and drop if so
		482
2305	hidnplayr	483	push [edx - sizeof.IPv4_header + IPv4_header.SourceAddress] ;;; FIXME
1838	hidnplayr	484	pop [ebx + IP_SOCKET.RemoteIP]
1733	hidnplayr	485
2305	hidnplayr	486	push [edx + TCP_header.SourcePort]
1838	hidnplayr	487	pop [ebx + TCP_SOCKET.RemotePort]
1733	hidnplayr	488
2305	hidnplayr	489	push [edx + TCP_header.SequenceNumber]
1838	hidnplayr	490	pop [ebx + TCP_SOCKET.IRS]
1733	hidnplayr	491
1838	hidnplayr	492	push [TCP_sequence_num] ;;;;;
		493	add [TCP_sequence_num], 64000 / 2
		494	pop [ebx + TCP_SOCKET.ISS]
1733	hidnplayr	495
1838	hidnplayr	496	push [ebx + TCP_SOCKET.ISS]
		497	pop [ebx + TCP_SOCKET.SND_NXT]
1733	hidnplayr	498
1838	hidnplayr	499	TCP_sendseqinit ebx
		500	TCP_rcvseqinit ebx
1733	hidnplayr	501
1838	hidnplayr	502	mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
		503	mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		504	mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval ;;;; macro
		505
		506	lea eax, [ebx + STREAM_SOCKET.snd]
1733	hidnplayr	507	call SOCKET_ring_create
		508
1838	hidnplayr	509	lea eax, [ebx + STREAM_SOCKET.rcv]
1733	hidnplayr	510	call SOCKET_ring_create
		511
1838	hidnplayr	512	;;; call SOCKET_notify_owner
1733	hidnplayr	513
		514	jmp .trim_then_step6
1838	hidnplayr	515
1733	hidnplayr	516
		517
		518
		519
		520
		521
		522
		523
1838	hidnplayr	524
1733	hidnplayr	525	;------------
		526	; Active Open
		527
		528	align 4
		529	.SYN_SENT:
		530
		531	DEBUGF 1,"TCP state: syn_sent\n"
		532
2305	hidnplayr	533	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	534	jz @f
		535
2305	hidnplayr	536	mov eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	537	cmp eax, [ebx + TCP_SOCKET.ISS]
2300	hidnplayr	538	jbe .drop_with_reset
1733	hidnplayr	539
		540	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
2300	hidnplayr	541	ja .drop_with_reset
1733	hidnplayr	542	@@:
		543
2305	hidnplayr	544	test [edx + TCP_header.Flags], TH_RST
1733	hidnplayr	545	jz @f
		546
2305	hidnplayr	547	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	548	jz .drop
		549
		550	mov eax, ebx
		551	mov ebx, ECONNREFUSED
		552	call TCP_drop
		553
		554	jmp .drop
		555	@@:
		556
2305	hidnplayr	557	test [edx + TCP_header.Flags], TH_SYN
1733	hidnplayr	558	jz .drop
		559
		560	; at this point, segment seems to be valid
		561
2305	hidnplayr	562	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	563	jz .no_syn_ack
		564
		565	; now, process received SYN in response to an active open
		566
2305	hidnplayr	567	mov eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	568	mov [ebx + TCP_SOCKET.SND_UNA], eax
		569	cmp eax, [ebx + TCP_SOCKET.SND_NXT]
2300	hidnplayr	570	jbe @f
1733	hidnplayr	571	mov [ebx + TCP_SOCKET.SND_NXT], eax
		572	@@:
		573
		574	.no_syn_ack:
		575
		576	mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; disable retransmission
		577
2305	hidnplayr	578	push [edx + TCP_header.SequenceNumber]
1733	hidnplayr	579	pop [ebx + TCP_SOCKET.IRS]
		580
		581	TCP_rcvseqinit ebx
		582
1763	hidnplayr	583	or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
1733	hidnplayr	584
		585	mov eax, [ebx + TCP_SOCKET.SND_UNA]
		586	cmp eax, [ebx + TCP_SOCKET.ISS]
2300	hidnplayr	587	jbe .simultaneous_open
1733	hidnplayr	588
2305	hidnplayr	589	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	590	jz .simultaneous_open
		591
		592	DEBUGF 1,"TCP: active open\n"
		593
		594	;;; TODO: update stats
		595
		596	; set socket state to connected
		597
		598	mov [ebx + SOCKET.state],1 ;;;; FIXME
		599
1831	hidnplayr	600	mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED
1733	hidnplayr	601
		602	;;; TODO: check if we should scale the connection (567-572)
		603	;;; TODO: update RTT estimators
		604
		605	jmp .trim_then_step6
		606
		607	.simultaneous_open:
		608
		609	DEBUGF 1,"TCP: simultaneous open\n"
		610	; We have received a syn but no ACK, so we are having a simultaneous open..
1831	hidnplayr	611	mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
1733	hidnplayr	612
		613
		614
		615
		616
		617
		618
		619	;-------------------------------------
		620	; Common processing for receipt of SYN
		621
		622	.trim_then_step6:
		623
2305	hidnplayr	624	inc [edx + TCP_header.SequenceNumber]
1733	hidnplayr	625
		626	;;; TODO: Drop any received data that follows receive window (590)
		627
2305	hidnplayr	628	mov eax, [edx + TCP_header.SequenceNumber]
1733	hidnplayr	629	mov [ebx + TCP_SOCKET.RCV_UP], eax
		630	dec eax
		631	mov [ebx + TCP_SOCKET.SND_WL1], eax
		632
		633	jmp .ack_processed
		634
		635
		636
		637
		638
		639
		640
		641
		642	.NOT_LISTEN_OR_SYN_SENT:
		643
		644	DEBUGF 1,"Slow TCP input: not listen or syn_sent state\n"
		645
		646	;--------------------------------------------
		647	; Protection Against Wrapped Sequence Numbers
		648
		649	; First, check if timestamp is present
		650
1763	hidnplayr	651	;;;; TODO 602
1733	hidnplayr	652
		653	; Then, check if at least some bytes of data are within window
		654
		655	;;;; TODO
		656
		657
		658
		659
		660
		661
		662
		663
		664	;----------------------------
		665	; trim any data not in window
		666
		667	; check for duplicate data at beginning of segment
		668
		669	mov eax, [ebx + TCP_SOCKET.RCV_NXT]
2305	hidnplayr	670	sub eax, [edx + TCP_header.SequenceNumber]
2300	hidnplayr	671	jbe .no_duplicate
1733	hidnplayr	672
1830	hidnplayr	673	DEBUGF 1,"Uh oh.. %u bytes of duplicate data!\n", eax
1763	hidnplayr	674
2305	hidnplayr	675	test [edx + TCP_header.Flags], TH_SYN
1763	hidnplayr	676	jz .no_dup_syn
1733	hidnplayr	677
		678	; remove duplicate syn
		679
2305	hidnplayr	680	and [edx + TCP_header.Flags], not (TH_SYN)
		681	inc [edx + TCP_header.SequenceNumber]
1733	hidnplayr	682
2305	hidnplayr	683	cmp [edx + TCP_header.UrgentPointer], 1
2300	hidnplayr	684	jbe @f
2305	hidnplayr	685	dec [edx + TCP_header.UrgentPointer]
1838	hidnplayr	686	jmp .dup_syn
1733	hidnplayr	687	@@:
2305	hidnplayr	688	and [edx + TCP_header.Flags], not (TH_URG)
1838	hidnplayr	689	.dup_syn:
1733	hidnplayr	690	dec eax
1763	hidnplayr	691	.no_dup_syn:
1733	hidnplayr	692
		693	; eax holds number of bytes to drop
		694
		695	; Check for entire duplicate packet
		696
		697	cmp eax, ecx
2300	hidnplayr	698	jae .duplicate
1733	hidnplayr	699
1830	hidnplayr	700	DEBUGF 1,"Going to drop %u out of %u bytes\n", eax, ecx
		701
1733	hidnplayr	702	;;; TODO: apply figure 28.30
		703
		704	; Check for duplicate FIN
		705
2305	hidnplayr	706	test [edx + TCP_header.Flags], TH_FIN
1733	hidnplayr	707	jz @f
		708	inc ecx
		709	cmp eax, ecx
		710	dec ecx
		711	jne @f
		712
		713	mov eax, ecx
2305	hidnplayr	714	and [edx + TCP_header.Flags], not TH_FIN
1733	hidnplayr	715	or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		716	jmp .no_duplicate
		717	@@:
		718
		719	; Handle the case when a bound socket connects to itself
		720	; Allow packets with a SYN and an ACKto continue with the processing
		721
		722	;-------------------------------------
		723	; Generate duplicate ACK if nescessary
		724
		725	; This code also handles simultaneous half-open or self-connects
		726
		727	test eax, eax
		728	jnz .drop_after_ack
		729
2305	hidnplayr	730	cmp [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	731	jz .drop_after_ack
		732
		733	.duplicate:
		734
		735	DEBUGF 1,"Duplicate received\n"
		736
		737	;----------------------------------------
		738	; Update statistics for duplicate packets
		739
		740	;;; TODO
		741
1830	hidnplayr	742	jmp .drop_after_ack
1733	hidnplayr	743
		744	.no_duplicate:
		745
		746	;-----------------------------------------------
		747	; Remove duplicate data and update urgent offset
		748
2305	hidnplayr	749	add [edx + TCP_header.SequenceNumber], eax
1733	hidnplayr	750
		751	;;; TODO
		752
2305	hidnplayr	753	sub [edx + TCP_header.UrgentPointer], ax
2300	hidnplayr	754	ja @f
1733	hidnplayr	755
2305	hidnplayr	756	and [edx + TCP_header.Flags], not (TH_URG)
		757	mov [edx + TCP_header.UrgentPointer], 0
1733	hidnplayr	758	@@:
		759
		760	;--------------------------------------------------
		761	; Handle data that arrives after process terminates
		762
		763	cmp [ebx + SOCKET.PID], 0
2300	hidnplayr	764	ja @f
1733	hidnplayr	765
1831	hidnplayr	766	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT
2300	hidnplayr	767	jbe @f
1733	hidnplayr	768
		769	test ecx, ecx
		770	jz @f
		771
		772	;;; Close the socket
		773	;;; update stats
		774
		775	jmp .drop_with_reset
		776	@@:
		777
		778	;----------------------------------------
		779	; Remove data beyond right edge of window
		780
2305	hidnplayr	781	mov eax, [edx + TCP_header.SequenceNumber]
1733	hidnplayr	782	add eax, ecx
		783	sub eax, [ebx + TCP_SOCKET.RCV_NXT]
		784	sub ax, [ebx + TCP_SOCKET.RCV_WND]
		785
		786	; eax now holds the number of bytes to drop
		787
2300	hidnplayr	788	jbe .no_excess_data
1733	hidnplayr	789
		790	;;; TODO: update stats
		791
		792	cmp eax, ecx
2300	hidnplayr	793	jb .dont_drop_all
1733	hidnplayr	794
		795	;;; TODO 700-736
		796
		797	.dont_drop_all:
		798
		799	.no_excess_data:
		800
		801
		802
		803
		804
		805
		806
		807
		808	;-----------------
		809	; Record timestamp
		810
		811	;;; TODO 737-746
		812
		813
		814
		815
		816
		817	;------------------
		818	; Process RST flags
		819
2305	hidnplayr	820	test [edx + TCP_header.Flags], TH_RST
1733	hidnplayr	821	jz .rst_skip
		822
		823	DEBUGF 1,"Got an RST flag"
		824
		825	mov eax, [ebx + TCP_SOCKET.t_state]
		826	shl eax, 2
		827	jmp dword [eax + .rst_sw_list]
		828
		829	.rst_sw_list:
1831	hidnplayr	830	dd .rst_skip ;TCPS_CLOSED
		831	dd .rst_skip ;TCPS_LISTEN
		832	dd .rst_skip ;TCPS_SYN_SENT
		833	dd .econnrefused ;TCPS_SYN_RECEIVED
		834	dd .econnreset ;TCPS_ESTABLISHED
		835	dd .econnreset ;TCPS_CLOSE_WAIT
		836	dd .econnreset ;TCPS_FIN_WAIT_1
		837	dd .rst_close ;TCPS_CLOSING
		838	dd .rst_close ;TCPS_LAST_ACK
		839	dd .econnreset ;TCPS_FIN_WAIT_2
		840	dd .rst_close ;TCPS_TIMED_WAIT
1733	hidnplayr	841
		842	.econnrefused:
		843	DEBUGF 1,"Connection refused"
		844
1831	hidnplayr	845	mov [ebx + SOCKET.errorcode], ECONNREFUSED
1733	hidnplayr	846	jmp .close
		847
		848	.econnreset:
		849	DEBUGF 1,"Connection reset"
		850
1831	hidnplayr	851	mov [ebx + SOCKET.errorcode], ECONNRESET
1733	hidnplayr	852
1831	hidnplayr	853	.close:
1733	hidnplayr	854	DEBUGF 1,"Closing connection"
		855
1831	hidnplayr	856	mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSED
		857	;;; TODO: update stats
		858	mov eax, ebx
		859	call TCP_close
		860	jmp .drop
1733	hidnplayr	861
		862	.rst_close:
		863	DEBUGF 1,"Closing with reset\n"
		864
1831	hidnplayr	865	mov eax, ebx
		866	call TCP_close
1733	hidnplayr	867	jmp .drop
		868
		869
		870
		871
		872
		873
		874
1763	hidnplayr	875	.rst_skip:
1733	hidnplayr	876
1763	hidnplayr	877
1733	hidnplayr	878	;--------------------------------------
		879	; handle SYN-full and ACK-less segments
		880
2305	hidnplayr	881	test [edx + TCP_header.Flags], TH_SYN
1733	hidnplayr	882	jz @f
		883
1831	hidnplayr	884	mov eax, ebx
1733	hidnplayr	885	mov ebx, ECONNRESET
		886	call TCP_drop
		887	jmp .drop_with_reset
		888
2305	hidnplayr	889	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	890	jz .drop
		891	@@:
		892
		893
		894
		895
		896
		897
		898
		899	;---------------
		900	; ACK processing
		901
1831	hidnplayr	902	cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
1733	hidnplayr	903	jnz .no_syn_rcv
		904
		905	DEBUGF 1,"TCP state = syn received\n"
		906
2305	hidnplayr	907	mov eax, [edx + TCP_header.AckNumber]
1838	hidnplayr	908	cmp [ebx + TCP_SOCKET.SND_UNA], eax
2300	hidnplayr	909	ja .drop_with_reset
1838	hidnplayr	910	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
2300	hidnplayr	911	ja .drop_with_reset
1733	hidnplayr	912
1831	hidnplayr	913	;;; update stats
		914	mov eax, ebx
		915	call SOCKET_is_connected
		916	mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED
		917
		918	; Do window scaling?
		919
		920	test [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE
		921	jz @f
		922	test [ebx + TCP_SOCKET.t_flags], TF_REQ_SCALE
		923	jz @f
		924
		925	;;; 810-811
		926
		927	@@:
		928
		929	;;; 813 ?
		930
2305	hidnplayr	931	mov eax, [edx + TCP_header.SequenceNumber]
1831	hidnplayr	932	dec eax
		933	mov [ebx + TCP_SOCKET.SND_WL1], eax
		934	jmp .not_dup_ack
		935
1733	hidnplayr	936	.no_syn_rcv:
		937
		938	; check for duplicate ACK
		939
2305	hidnplayr	940	mov eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	941	cmp eax, [ebx + TCP_SOCKET.SND_UNA]
2300	hidnplayr	942	ja .not_dup_ack
1733	hidnplayr	943
		944	test ecx, ecx
1763	hidnplayr	945	jnz .reset_dupacks
1733	hidnplayr	946
2305	hidnplayr	947	mov eax, dword [edx + TCP_header.Window]
1733	hidnplayr	948	cmp eax, [ebx + TCP_SOCKET.SND_WND]
1763	hidnplayr	949	jne .reset_dupacks
1733	hidnplayr	950
1763	hidnplayr	951	DEBUGF 1,"Processing a duplicate ACK..\n"
1733	hidnplayr	952
1763	hidnplayr	953	cmp [ebx + TCP_SOCKET.timer_retransmission], 10000 ;;;;
2300	hidnplayr	954	ja @f
1733	hidnplayr	955
2305	hidnplayr	956	mov eax, [edx + TCP_header.AckNumber]
1763	hidnplayr	957	cmp eax, [ebx + TCP_SOCKET.SND_UNA]
		958	je .dup_ack
		959
		960	@@:
		961	mov [ebx + TCP_SOCKET.t_dupacks], 0
		962	jmp .not_dup_ack
		963
		964	.dup_ack:
		965	inc [ebx + TCP_SOCKET.t_dupacks]
		966	cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh
		967	jne .no_re_xmit
		968
		969	push [ebx + TCP_SOCKET.SND_NXT] ; >>>>
		970
		971	mov eax, [ebx + TCP_SOCKET.SND_WND]
		972	cmp eax, [ebx + TCP_SOCKET.SND_CWND]
		973	cmovg eax, [ebx + TCP_SOCKET.SND_CWND]
		974	shr eax, 1
		975	push edx
		976	xor edx, edx
		977	div [ebx + TCP_SOCKET.t_maxseg]
		978	cmp eax, 2
2300	hidnplayr	979	jae @f
1763	hidnplayr	980	mov ax, 2
		981	@@:
		982	mul [ebx + TCP_SOCKET.t_maxseg]
		983	pop edx
		984	mov [ebx + TCP_SOCKET.SND_SSTHRESH], eax
		985
		986	mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; turn off retransmission timer
		987	mov [ebx + TCP_SOCKET.t_rtt], 0
2305	hidnplayr	988	mov eax, [edx + TCP_header.AckNumber]
1763	hidnplayr	989	mov [ebx + TCP_SOCKET.SND_NXT], eax
		990	mov eax, [ebx + TCP_SOCKET.t_maxseg]
		991	mov [ebx + TCP_SOCKET.SND_CWND], eax
		992
		993	mov eax, ebx
		994	call TCP_output ; retransmit missing segment
		995
		996	push edx
		997	xor edx, edx
		998	mov eax, [ebx + TCP_SOCKET.t_maxseg]
		999	mul [ebx + TCP_SOCKET.t_dupacks]
		1000	pop edx
		1001	add eax, [ebx + TCP_SOCKET.SND_SSTHRESH]
		1002	mov [ebx + TCP_SOCKET.SND_CWND], eax
		1003
		1004	pop eax ; <<<<
		1005	cmp eax, [ebx + TCP_SOCKET.SND_NXT]
2300	hidnplayr	1006	jb @f
1763	hidnplayr	1007	mov [ebx + TCP_SOCKET.SND_NXT], eax
		1008	@@:
		1009
1733	hidnplayr	1010	jmp .drop
		1011
		1012
1763	hidnplayr	1013	.no_re_xmit:
2300	hidnplayr	1014	jbe .not_dup_ack
1733	hidnplayr	1015
1763	hidnplayr	1016	DEBUGF 1,"Increasing congestion window\n"
1733	hidnplayr	1017
1763	hidnplayr	1018	mov eax, [ebx + TCP_SOCKET.t_maxseg]
		1019	add [ebx + TCP_SOCKET.SND_CWND], eax
1733	hidnplayr	1020
1763	hidnplayr	1021	mov eax, ebx
		1022	call TCP_output
1733	hidnplayr	1023
1763	hidnplayr	1024	jmp .drop
1733	hidnplayr	1025
		1026
		1027
1763	hidnplayr	1028
		1029
		1030
		1031	.not_dup_ack:
		1032
1733	hidnplayr	1033	;-------------------------------------------------
		1034	; If the congestion window was inflated to account
		1035	; for the other side's cached packets, retract it
		1036
1763	hidnplayr	1037	mov eax, [ebx + TCP_SOCKET.SND_SSTHRESH]
		1038	cmp eax, [ebx + TCP_SOCKET.SND_CWND]
2300	hidnplayr	1039	ja @f
1763	hidnplayr	1040	cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh
2300	hidnplayr	1041	jbe @f
1763	hidnplayr	1042	mov [ebx + TCP_SOCKET.SND_CWND], eax
		1043	@@:
1733	hidnplayr	1044
1763	hidnplayr	1045	mov [ebx + TCP_SOCKET.t_dupacks], 0
1733	hidnplayr	1046
2305	hidnplayr	1047	mov eax, [edx + TCP_header.AckNumber]
1763	hidnplayr	1048	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
2300	hidnplayr	1049	jbe @f
1733	hidnplayr	1050
1763	hidnplayr	1051	;;; TODO: update stats
		1052	jmp .drop_after_ack
1733	hidnplayr	1053
1763	hidnplayr	1054	@@:
1733	hidnplayr	1055
2305	hidnplayr	1056	mov edi, [edx + TCP_header.AckNumber]
1763	hidnplayr	1057	sub edi, [ebx + TCP_SOCKET.SND_UNA] ; now we got the number of acked bytes in esi
1733	hidnplayr	1058
1763	hidnplayr	1059	;;; TODO: update stats
1733	hidnplayr	1060
		1061
1763	hidnplayr	1062	DEBUGF 1,"We have an acceptable ACK of %x bytes\n", esi
		1063
		1064
		1065
		1066
		1067
		1068
1733	hidnplayr	1069	;------------------------------------------
		1070	; RTT measurements and retransmission timer
		1071
1763	hidnplayr	1072	;;;;; 912 - 926
1733	hidnplayr	1073
		1074	mov [ebx + TCP_SOCKET.timer_retransmission], 0
		1075
		1076	mov eax, [ebx + TCP_SOCKET.SND_MAX]
2305	hidnplayr	1077	cmp eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	1078	je .all_outstanding
		1079	mov [ebx + TCP_SOCKET.timer_retransmission], 120 ;;;; TODO: correct this value (use a macro for it)
		1080	.all_outstanding:
		1081
		1082
		1083
		1084
		1085
		1086
		1087
		1088	;-------------------------------------------
		1089	; Open congestion window in response to ACKs
		1090
1763	hidnplayr	1091	mov esi, [ebx + TCP_SOCKET.SND_CWND]
		1092	mov eax, [ebx + TCP_SOCKET.t_maxseg]
1733	hidnplayr	1093
1763	hidnplayr	1094	cmp esi, [ebx + TCP_SOCKET.SND_SSTHRESH]
2300	hidnplayr	1095	jbe @f
1763	hidnplayr	1096	push edx
		1097	push eax
		1098	mul eax
		1099	div esi
		1100	pop edx
		1101	shr edx, 3
		1102	add eax, edx
		1103	pop edx
		1104	@@:
1733	hidnplayr	1105
1763	hidnplayr	1106	add esi, eax
1733	hidnplayr	1107
1763	hidnplayr	1108	push ecx
		1109	mov cl, [ebx + TCP_SOCKET.SND_SCALE]
		1110	mov eax, TCP_max_win
		1111	shl eax, cl
		1112	pop ecx
1733	hidnplayr	1113
1763	hidnplayr	1114	cmp esi, eax
		1115	cmovg esi, eax
		1116	mov [ebx + TCP_SOCKET.SND_CWND], esi
1733	hidnplayr	1117
		1118
		1119
		1120
1763	hidnplayr	1121
		1122
		1123
1733	hidnplayr	1124	;------------------------------------------
		1125	; Remove acknowledged data from send buffer
		1126
1763	hidnplayr	1127	push ecx edx ebx
		1128	mov ecx, edi
1733	hidnplayr	1129	lea eax, [ebx + STREAM_SOCKET.snd]
		1130	call SOCKET_ring_free
1763	hidnplayr	1131	pop ebx
		1132	sub [ebx + TCP_SOCKET.SND_WND], ecx
		1133	pop edx ecx
1733	hidnplayr	1134
		1135	; Wake up process waiting on send buffer
		1136
		1137	mov eax, ebx
		1138	call SOCKET_notify_owner
		1139
1831	hidnplayr	1140	; Update TCPS
1733	hidnplayr	1141
2305	hidnplayr	1142	mov eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	1143	mov [ebx + TCP_SOCKET.SND_UNA], eax
		1144
		1145	cmp eax, [ebx + TCP_SOCKET.SND_NXT]
2300	hidnplayr	1146	jb @f
1733	hidnplayr	1147	mov [ebx + TCP_SOCKET.SND_NXT], eax
		1148	@@:
		1149
		1150
1772	hidnplayr	1151	;; TODO: use zero flag as 'ourfinisacked'
1733	hidnplayr	1152
		1153
		1154
		1155
		1156	; General ACK handling complete
		1157	; Now do the state-specific ones
		1158
		1159	mov eax, [ebx + TCP_SOCKET.t_state]
		1160	jmp dword [eax*4 + .ACK_sw_list]
		1161
		1162	.ACK_sw_list:
1831	hidnplayr	1163	dd .ack_processed ;TCPS_CLOSED
		1164	dd .ack_processed ;TCPS_LISTEN
		1165	dd .ack_processed ;TCPS_SYN_SENT
		1166	dd .ack_processed ;TCPS_SYN_RECEIVED
		1167	dd .ack_processed ;TCPS_ESTABLISHED
		1168	dd .ack_processed ;TCPS_CLOSE_WAIT
		1169	dd .ack_fw1 ;TCPS_FIN_WAIT_1
		1170	dd .ack_c ;TCPS_CLOSING
		1171	dd .ack_la ;TCPS_LAST_ACK
		1172	dd .ack_processed ;TCPS_FIN_WAIT_2
		1173	dd .ack_tw ;TCPS_TIMED_WAIT
1733	hidnplayr	1174
		1175
1772	hidnplayr	1176	.ack_fw1:
		1177	jz .ack_processed
1733	hidnplayr	1178
1773	hidnplayr	1179	test [ebx + SOCKET.state], SS_CANTRCVMORE
1772	hidnplayr	1180	jnz @f
1773	hidnplayr	1181	mov eax, ebx
		1182	call SOCKET_is_disconnected
		1183	;;; mov [ebx + TCP_SOCKET.timer_timed_wait], TCP_time_max_idle
1772	hidnplayr	1184	@@:
1733	hidnplayr	1185
1831	hidnplayr	1186	mov [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2
1733	hidnplayr	1187	jmp .ack_processed
		1188
		1189
1772	hidnplayr	1190	.ack_c:
		1191	jz .ack_processed
		1192
1831	hidnplayr	1193	mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT
1773	hidnplayr	1194	mov eax, ebx
1772	hidnplayr	1195	call TCP_cancel_timers
		1196	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
1773	hidnplayr	1197	mov eax, ebx
		1198	call SOCKET_is_disconnected
1733	hidnplayr	1199	jmp .ack_processed
		1200
		1201
1772	hidnplayr	1202	.ack_la:
		1203	jz .ack_processed
1733	hidnplayr	1204
1773	hidnplayr	1205
		1206	mov eax, ebx
1772	hidnplayr	1207	call TCP_close
		1208	jmp .drop
1733	hidnplayr	1209
		1210
1772	hidnplayr	1211	.ack_tw:
		1212	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1213	jmp .drop_after_ack
1733	hidnplayr	1214
		1215
1772	hidnplayr	1216
		1217
		1218
		1219
		1220
1763	hidnplayr	1221	.reset_dupacks: ; We got a new ACK, reset duplicate ACK counter
1733	hidnplayr	1222
1763	hidnplayr	1223	mov [ebx + TCP_SOCKET.t_dupacks], 0
1733	hidnplayr	1224
		1225	.ack_processed: ; (step 6)
		1226
		1227	DEBUGF 1,"ACK processed\n"
		1228
		1229	;----------------------------------------------
		1230	; check if we need to update window information
		1231
2305	hidnplayr	1232	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	1233	jz .no_window_update
		1234
		1235	mov eax, [ebx + TCP_SOCKET.SND_WL1]
2305	hidnplayr	1236	cmp eax, [edx + TCP_header.SequenceNumber]
2300	hidnplayr	1237	jb .update_window
		1238	ja @f
1733	hidnplayr	1239
		1240	mov eax, [ebx + TCP_SOCKET.SND_WL2]
2305	hidnplayr	1241	cmp eax, [edx + TCP_header.AckNumber]
2300	hidnplayr	1242	jb .update_window
		1243	ja .no_window_update
1733	hidnplayr	1244	@@:
		1245
		1246	mov eax, [ebx + TCP_SOCKET.SND_WL2]
2305	hidnplayr	1247	cmp eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	1248	jne .no_window_update
		1249
2305	hidnplayr	1250	movzx eax, [edx + TCP_header.Window]
1733	hidnplayr	1251	cmp eax, [ebx + TCP_SOCKET.SND_WND]
2300	hidnplayr	1252	jbe .no_window_update
1733	hidnplayr	1253
		1254	.update_window:
		1255
		1256	DEBUGF 1,"Updating window\n"
		1257
		1258	; Keep track of pure window updates
		1259
		1260	; test ecx, ecx
		1261	; jz @f
		1262	;
		1263	; mov eax, [ebx + TCP_SOCKET.SND_WL2]
2305	hidnplayr	1264	; cmp eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	1265	; jne @f
		1266	;
		1267	; ;; mov eax, tiwin
		1268	; cmp eax, [ebx + TCP_SOCKET.SND_WND]
2300	hidnplayr	1269	; jbe @f
1733	hidnplayr	1270	;
		1271	; ;;; update stats
		1272	;
		1273	; @@:
		1274
2305	hidnplayr	1275	mov eax, dword [edx + TCP_header.Window]
1733	hidnplayr	1276	cmp eax, [ebx + TCP_SOCKET.max_sndwnd]
2300	hidnplayr	1277	jbe @f
1733	hidnplayr	1278	mov [ebx + TCP_SOCKET.max_sndwnd], eax
		1279	@@:
		1280	mov [ebx + TCP_SOCKET.SND_WND], eax
		1281
2305	hidnplayr	1282	push [edx + TCP_header.SequenceNumber]
1733	hidnplayr	1283	pop [ebx + TCP_SOCKET.SND_WL1]
		1284
2305	hidnplayr	1285	push [edx + TCP_header.AckNumber]
1733	hidnplayr	1286	pop [ebx + TCP_SOCKET.SND_WL2]
		1287
		1288	;;; needoutput = 1
		1289
		1290	.no_window_update:
		1291
		1292
		1293
		1294
		1295
		1296
		1297
		1298	;-----------------
		1299	; process URG flag
		1300
2305	hidnplayr	1301	test [edx + TCP_header.Flags], TH_URG
1733	hidnplayr	1302	jz .not_urgent
		1303
2305	hidnplayr	1304	cmp [edx + TCP_header.UrgentPointer], 0
1733	hidnplayr	1305	jz .not_urgent
		1306
1831	hidnplayr	1307	cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT
1733	hidnplayr	1308	je .not_urgent
		1309
		1310	; Ignore bogus urgent offsets
		1311
		1312	;;; 1040-1050
		1313
2305	hidnplayr	1314	movzx eax, [edx + TCP_header.UrgentPointer]
1733	hidnplayr	1315	add eax, [ebx + STREAM_SOCKET.rcv + RING_BUFFER.size]
		1316	cmp eax, SOCKET_MAXDATA
2300	hidnplayr	1317	jbe .not_urgent
1733	hidnplayr	1318
2305	hidnplayr	1319	mov [edx + TCP_header.UrgentPointer], 0
		1320	and [edx + TCP_header.Flags], not (TH_URG)
1733	hidnplayr	1321	jmp .do_data
		1322
		1323	.not_urgent:
		1324
		1325	; processing of received urgent pointer
		1326
		1327	;;; TODO (1051-1093)
		1328
		1329
		1330
		1331
		1332
		1333
		1334
		1335
		1336	;--------------------------------
		1337	; process the data in the segment
		1338
		1339	.do_data:
		1340
		1341	DEBUGF 1,"TCP: do data (%u)\n", ecx
		1342
2305	hidnplayr	1343	test [edx + TCP_header.Flags], TH_FIN
1733	hidnplayr	1344	jnz .process_fin
		1345
1831	hidnplayr	1346	cmp [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_1
2300	hidnplayr	1347	jae .dont_do_data
1733	hidnplayr	1348
		1349	test ecx, ecx
		1350	jz .final_processing
		1351
		1352	DEBUGF 1,"Processing data in segment\n"
		1353
		1354	;; TODO: check if data is in sequence !
		1355
2305	hidnplayr	1356	movzx eax, [edx + TCP_header.DataOffset] ;;; todo: remember this in.. edi ?
1733	hidnplayr	1357	and eax, 0xf0
		1358	shr al, 2
		1359
		1360	lea esi, [edx + eax]
		1361
		1362	or [ebx + TCP_SOCKET.t_flags], TF_DELACK
		1363	add [ebx + TCP_SOCKET.RCV_NXT], ecx
		1364
		1365	lea eax, [ebx + STREAM_SOCKET.rcv]
		1366	call SOCKET_ring_write
		1367
		1368	mov eax, ebx
		1369	call SOCKET_notify_owner
		1370
		1371	jmp .final_processing
		1372
		1373
		1374	.dont_do_data:
		1375
		1376
		1377
		1378
		1379
		1380
		1381
		1382	;---------------
		1383	; FIN processing
		1384
		1385	.process_fin:
		1386
		1387	DEBUGF 1,"Processing FIN\n"
		1388
1831	hidnplayr	1389	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT
1774	hidnplayr	1390	je .not_first_fin
1831	hidnplayr	1391	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSING
1774	hidnplayr	1392	je .not_first_fin
1831	hidnplayr	1393	cmp [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2
1774	hidnplayr	1394	je .not_first_fin
		1395
		1396	DEBUGF 1,"First FIN for this connection\n"
		1397
		1398	mov eax, ebx
		1399	call SOCKET_cant_recv_more
		1400
		1401	mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		1402	inc [ebx + TCP_SOCKET.RCV_NXT]
		1403
		1404	.not_first_fin:
1733	hidnplayr	1405	mov eax, [ebx + TCP_SOCKET.t_state]
		1406	shl eax, 2
		1407	jmp dword [eax + .FIN_sw_list]
		1408
		1409	.FIN_sw_list:
1831	hidnplayr	1410	dd .no_fin ;TCPS_CLOSED
		1411	dd .no_fin ;TCPS_LISTEN
		1412	dd .no_fin ;TCPS_SYN_SENT
		1413	dd .fin_syn_est ;TCPS_SYN_RECEIVED
		1414	dd .fin_syn_est ;TCPS_ESTABLISHED
		1415	dd .no_fin ;TCPS_CLOSE_WAIT
		1416	dd .fin_wait1 ;TCPS_FIN_WAIT_1
		1417	dd .no_fin ;TCPS_CLOSING
		1418	dd .no_fin ;TCPS_LAST_ACK
		1419	dd .fin_wait2 ;TCPS_FIN_WAIT_2
		1420	dd .fin_timed ;TCPS_TIMED_WAIT
1733	hidnplayr	1421
		1422	.fin_syn_est:
		1423
1831	hidnplayr	1424	mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT
1774	hidnplayr	1425	jmp .no_fin
1733	hidnplayr	1426
		1427	.fin_wait1:
		1428
1831	hidnplayr	1429	mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSING
1774	hidnplayr	1430	jmp .no_fin
1733	hidnplayr	1431
		1432	.fin_wait2:
		1433
1831	hidnplayr	1434	mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT
1774	hidnplayr	1435	mov eax, ebx
		1436	call TCP_cancel_timers
		1437	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1438	call SOCKET_is_disconnected
		1439	jmp .no_fin
1733	hidnplayr	1440
		1441	.fin_timed:
1774	hidnplayr	1442	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1443	jmp .no_fin
1733	hidnplayr	1444
		1445	.no_fin:
		1446
		1447
		1448
		1449
		1450
		1451
		1452
		1453
		1454	;-----------------
		1455	; Final processing
		1456
		1457	.final_processing:
		1458
		1459	DEBUGF 1,"Final processing\n"
		1460
		1461	;;; if debug enabled, output packet
		1462
		1463	;test needoutput, needoutput
		1464	;jz .dumpit
		1465
		1466	test [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		1467	jz .dumpit
		1468
		1469	DEBUGF 1,"ACK now!\n"
		1470
		1471	push ebx
		1472	mov eax, ebx
		1473	call TCP_output
		1474	pop ebx
		1475
		1476	.dumpit:
		1477
		1478	mov [ebx + SOCKET.lock], 0
		1479
		1480	call kernel_free
		1481	add esp, 4
		1482	ret
		1483
		1484
		1485
		1486
		1487
		1488
		1489
		1490	;------------------------------------------
		1491	; Generate an ACK, droping incoming segment
		1492
		1493	align 4
		1494	.drop_after_ack:
		1495
		1496	DEBUGF 1,"Drop after ACK\n"
		1497
2305	hidnplayr	1498	test [edx + TCP_header.Flags], TH_RST
1733	hidnplayr	1499	jnz .drop
		1500
		1501	and [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		1502
		1503	mov [ebx + SOCKET.lock], 0
		1504
		1505	push ebx
1838	hidnplayr	1506	; mov cl, TH_ACK
		1507	; call TCP_respond_socket
		1508	mov eax, ebx
		1509	call TCP_output
1733	hidnplayr	1510	pop ebx
		1511
		1512	call kernel_free
		1513	add esp, 4
		1514	ret
		1515
		1516
		1517
		1518
		1519
		1520
		1521
		1522
		1523	;-------------------------------------------
		1524	; Generate an RST, dropping incoming segment
		1525
		1526	align 4
		1527	.drop_with_reset:
		1528
		1529	mov [ebx + SOCKET.lock], 0
		1530
		1531	.drop_with_reset_not_locked:
		1532
		1533	DEBUGF 1,"Drop with reset\n"
		1534
2305	hidnplayr	1535	test [edx + TCP_header.Flags], TH_RST
1733	hidnplayr	1536	jnz .drop
		1537
		1538	;;; if its a multicast/broadcast, also drop
		1539
2305	hidnplayr	1540	test [edx + TCP_header.Flags], TH_ACK
1733	hidnplayr	1541	jnz .respond_ack
		1542
2305	hidnplayr	1543	test [edx + TCP_header.Flags], TH_SYN
1733	hidnplayr	1544	jnz .respond_syn
		1545
		1546	call kernel_free
		1547	add esp, 4
		1548	ret
		1549
		1550	.respond_ack:
		1551
		1552	push ebx
1830	hidnplayr	1553	mov cl, TH_RST
		1554	call TCP_respond_socket
1733	hidnplayr	1555	pop ebx
		1556
		1557	jmp .destroy_new_socket
		1558
		1559
		1560	.respond_syn:
		1561
		1562	push ebx
1830	hidnplayr	1563	mov cl, TH_RST + TH_ACK
1733	hidnplayr	1564	call TCP_respond_socket
		1565	pop ebx
		1566
		1567	jmp .destroy_new_socket
		1568
		1569
		1570
		1571
		1572
		1573
		1574
		1575	;-----
		1576	; Drop
		1577
		1578	align 4
		1579	.drop:
		1580
		1581	mov [ebx + SOCKET.lock], 0
		1582
		1583	.drop_not_locked:
		1584
		1585	DEBUGF 1,"Dropping packet\n"
		1586
		1587	;;;; If debugging options are enabled, output the packet somwhere
		1588
		1589	.destroy_new_socket:
		1590
		1591	;;;; kill the newly created socket
		1592
		1593	call kernel_free
		1594	add esp, 4
		1595	ret

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(root)/kernel/branches/net/network/tcp_input.inc @ 2555 – Rev 2305