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

Rev	Author	Line No.	Line
1763	hidnplayr	1	;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
		2	;; ;;
2362	hidnplayr	3	;; Copyright (C) KolibriOS team 2004-2012. All rights reserved. ;;
1763	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
		17	$Revision: 2555 $
		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
2310	hidnplayr	27	; esi = ptr to TCP segment
2308	hidnplayr	28	; edi = ptr to ipv4 source address, followed by ipv4 dest address
1733	hidnplayr	29	;
		30	; OUT: /
		31	;
		32	;-----------------------------------------------------------------
1830	hidnplayr	33
1733	hidnplayr	34	align 4
		35	TCP_input:
		36
2390	hidnplayr	37	DEBUGF 1,"TCP_input size=%u\n", ecx
1733	hidnplayr	38
2390	hidnplayr	39	; First, re-calculate the checksum
1733	hidnplayr	40
2390	hidnplayr	41	push ecx esi
		42	pushw [esi + TCP_header.Checksum]
		43	mov [esi + TCP_header.Checksum], 0
		44	TCP_checksum (edi), (edi+4)
		45	pop cx ; previous checksum
		46	cmp cx, dx
		47	pop edx ecx
		48	jne .drop_not_locked
1733	hidnplayr	49
2390	hidnplayr	50	DEBUGF 1,"Checksum ok\n"
1733	hidnplayr	51
2390	hidnplayr	52	and [edx + TCP_header.DataOffset], 0xf0 ; Calculate TCP segment header size (throwing away unused reserved bits in TCP header)
		53	shr [edx + TCP_header.DataOffset], 2
		54	cmp [edx + TCP_header.DataOffset], sizeof.TCP_header ; Now see if it's at least the size of a standard TCP header
		55	jb .drop_not_locked ; If not, drop the packet
1733	hidnplayr	56
2390	hidnplayr	57	movzx eax, [edx + TCP_header.DataOffset]
		58	sub ecx, eax ; substract TCP header size from total segment size
		59	jb .drop_not_locked ; If total segment size is less then the advertised header size, drop packet
		60	DEBUGF 1,"we got %u bytes of data\n", ecx
1733	hidnplayr	61
		62	;-----------------------------------------------------------------------------------------
		63	; Check if this packet has a timestamp option (We do it here so we can process it quickly)
		64
2390	hidnplayr	65	cmp eax, sizeof.TCP_header + 12 ; Timestamp option is 12 bytes
		66	jb .no_timestamp
		67	je .is_ok
1733	hidnplayr	68
2390	hidnplayr	69	cmp byte [edx + sizeof.TCP_header + 12], TCP_OPT_EOL ; end of option list
		70	jne .no_timestamp
1733	hidnplayr	71
		72	.is_ok:
2390	hidnplayr	73	test [edx + TCP_header.Flags], TH_SYN ; SYN flag must not be set
		74	jnz .no_timestamp
1733	hidnplayr	75
2390	hidnplayr	76	cmp dword [edx + sizeof.TCP_header], 0x0101080a ; Timestamp header
		77	jne .no_timestamp
1733	hidnplayr	78
2390	hidnplayr	79	DEBUGF 1,"timestamp ok\n"
1733	hidnplayr	80
2390	hidnplayr	81	; TODO: Parse the option
		82	; TODO: Set a Bit in the TCP to tell all options are parsed
1733	hidnplayr	83
		84	.no_timestamp:
		85
		86	;-------------------------------------------
		87	; Convert Big-endian values to little endian
		88
2390	hidnplayr	89	ntohd [edx + TCP_header.SequenceNumber]
		90	ntohd [edx + TCP_header.AckNumber]
1733	hidnplayr	91
2390	hidnplayr	92	ntohw [edx + TCP_header.Window]
		93	ntohw [edx + TCP_header.UrgentPointer]
		94	ntohw [edx + TCP_header.SourcePort]
		95	ntohw [edx + TCP_header.DestinationPort]
1733	hidnplayr	96
		97	;------------------------------------------------------------
1831	hidnplayr	98	; Next thing to do is find the TCPS (thus, the socket pointer)
1733	hidnplayr	99
		100	; IP Packet TCP Destination Port = local Port
		101	; (IP Packet SenderAddress = Remote IP) OR (Remote IP = 0)
2309	hidnplayr	102	; (IP Packet TCP Source Port = remote Port) OR (remote Port = 0)
1733	hidnplayr	103
2390	hidnplayr	104	mov ebx, net_sockets
		105	mov si, [edx + TCP_header.DestinationPort]
1733	hidnplayr	106
		107	.socket_loop:
2390	hidnplayr	108	mov ebx, [ebx + SOCKET.NextPtr]
		109	or ebx, ebx
		110	jz .drop_with_reset_not_locked
1733	hidnplayr	111
2390	hidnplayr	112	cmp [ebx + SOCKET.Domain], AF_INET4
		113	jne .socket_loop
1733	hidnplayr	114
2390	hidnplayr	115	cmp [ebx + SOCKET.Protocol], IP_PROTO_TCP
		116	jne .socket_loop
1733	hidnplayr	117
2390	hidnplayr	118	cmp [ebx + TCP_SOCKET.LocalPort], si
		119	jne .socket_loop
1733	hidnplayr	120
2390	hidnplayr	121	mov eax, [ebx + IP_SOCKET.RemoteIP]
		122	cmp eax, [edi] ; Ipv4 source addres
		123	je @f
		124	test eax, eax
		125	jnz .socket_loop
1733	hidnplayr	126	@@:
		127
2390	hidnplayr	128	mov ax, [ebx + TCP_SOCKET.RemotePort]
		129	cmp [edx + TCP_header.SourcePort], ax
		130	je .found_socket
		131	test ax, ax
		132	jnz .socket_loop
		133	.found_socket: ; ebx now contains the socketpointer
		134	DEBUGF 1,"Socket ptr: %x\n", ebx
1733	hidnplayr	135
		136
		137	;----------------------------
		138	; Check if socket isnt closed
		139
2390	hidnplayr	140	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSED
		141	je .drop_not_locked
1733	hidnplayr	142
		143	;----------------
		144	; Lock the socket
		145
2402	hidnplayr	146	pusha
		147	lea ecx, [ebx + SOCKET.mutex]
		148	call mutex_lock
		149	popa
1830	hidnplayr	150
2390	hidnplayr	151	DEBUGF 1,"Socket locked\n"
1733	hidnplayr	152
		153	;---------------------------------------
		154	; unscale the window into a 32 bit value
		155
2390	hidnplayr	156	movzx eax, [edx + TCP_header.Window]
		157	push ecx
		158	mov cl, [ebx + TCP_SOCKET.SND_SCALE]
		159	shl eax, cl
		160	mov dword [edx + TCP_header.Window], eax ; word after window is checksum, we dont need checksum anymore
		161	pop ecx
1733	hidnplayr	162
		163	;-----------------------------------
		164	; Is this socket a listening socket?
		165
2390	hidnplayr	166	test [ebx + SOCKET.options], SO_ACCEPTCON
		167	jz .no_listening_socket
1733	hidnplayr	168
2390	hidnplayr	169	DEBUGF 1,"Accepting new connection\n"
1838	hidnplayr	170
2402	hidnplayr	171	pusha
		172	lea ecx, [ebx + SOCKET.mutex]
		173	call mutex_unlock
		174	popa
		175
2390	hidnplayr	176	push ecx edx esi edi ;;;
		177	call SOCKET_fork
		178	pop edi esi edx ecx
1838	hidnplayr	179
2390	hidnplayr	180	test eax, eax
		181	jz .drop
1733	hidnplayr	182
2390	hidnplayr	183	push dword [edi + 4] ; Ipv4 destination addres
		184	pop [eax + IP_SOCKET.LocalIP]
1733	hidnplayr	185
2390	hidnplayr	186	push [edx + TCP_header.DestinationPort]
		187	pop [eax + TCP_SOCKET.LocalPort]
1733	hidnplayr	188
2390	hidnplayr	189	mov [eax + TCP_SOCKET.t_state], TCPS_LISTEN
		190	mov ebx, eax
1733	hidnplayr	191
2390	hidnplayr	192	jmp .LISTEN
1838	hidnplayr	193
1733	hidnplayr	194	.no_listening_socket:
		195
		196	;-------------------------------------
		197	; Reset idle timer and keepalive timer
		198
2390	hidnplayr	199	mov [ebx + TCP_SOCKET.t_idle], 0
		200	mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval
1733	hidnplayr	201
		202	;--------------------
		203	; Process TCP options
		204
2390	hidnplayr	205	movzx eax, [edx + TCP_header.DataOffset]
		206	cmp eax, sizeof.TCP_header ; Does header contain any options?
		207	je .no_options
1733	hidnplayr	208
2390	hidnplayr	209	DEBUGF 1,"Segment has options\n"
1733	hidnplayr	210
2390	hidnplayr	211	cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN ; no options when in listen state
		212	jz .not_uni_xfer ; also no header prediction
1733	hidnplayr	213
2390	hidnplayr	214	add eax, edx
		215	lea esi, [edx + sizeof.TCP_header]
1733	hidnplayr	216
		217	.opt_loop:
2390	hidnplayr	218	cmp esi, eax ; are we scanning outside of header?
		219	jae .no_options
1733	hidnplayr	220
2390	hidnplayr	221	cmp byte [esi], TCP_OPT_EOL ; end of option list?
		222	jz .no_options
1733	hidnplayr	223
2390	hidnplayr	224	cmp byte [esi], TCP_OPT_NOP ; nop ?
		225	jz .opt_nop
1733	hidnplayr	226
2390	hidnplayr	227	cmp byte [esi], TCP_OPT_MAXSEG
		228	je .opt_maxseg
1733	hidnplayr	229
2390	hidnplayr	230	cmp byte [esi], TCP_OPT_WINDOW
		231	je .opt_window
1733	hidnplayr	232
2390	hidnplayr	233	cmp byte [esi], TCP_OPT_TIMESTAMP
		234	je .opt_timestamp
1733	hidnplayr	235
2390	hidnplayr	236	jmp .no_options ; If we reach here, some unknown options were received, skip them all!
1733	hidnplayr	237
		238	.opt_nop:
2390	hidnplayr	239	inc edi
		240	jmp .opt_loop
1733	hidnplayr	241
		242	.opt_maxseg:
2390	hidnplayr	243	cmp byte [esi+1], 4
		244	jne .no_options ; error occured, ignore all options!
1733	hidnplayr	245
2390	hidnplayr	246	test [edx + TCP_header.Flags], TH_SYN
		247	jz @f
1733	hidnplayr	248
2390	hidnplayr	249	movzx eax, word[esi+2]
		250	rol ax, 8
		251	DEBUGF 1,"Maxseg: %u\n", ax
1733	hidnplayr	252
2390	hidnplayr	253	mov [ebx + TCP_SOCKET.t_maxseg], eax
1733	hidnplayr	254
		255	@@:
2390	hidnplayr	256	add edi, 4
		257	jmp .opt_loop
1733	hidnplayr	258
		259
		260	.opt_window:
2390	hidnplayr	261	cmp byte [esi+1], 3
		262	jne .no_options
1733	hidnplayr	263
2390	hidnplayr	264	test [edx + TCP_header.Flags], TH_SYN
		265	jz @f
1733	hidnplayr	266
2390	hidnplayr	267	DEBUGF 1,"Got window option\n"
1733	hidnplayr	268
2390	hidnplayr	269	;;;;;
1733	hidnplayr	270	@@:
2390	hidnplayr	271	add edi, 3
		272	jmp .opt_loop
1733	hidnplayr	273
		274
		275	.opt_timestamp:
2390	hidnplayr	276	cmp byte [esi+1], 10
		277	jne .no_options
1733	hidnplayr	278
2390	hidnplayr	279	DEBUGF 1,"Got timestamp option\n"
1733	hidnplayr	280
2390	hidnplayr	281	;;;;;
1733	hidnplayr	282
2390	hidnplayr	283	add esi, 10
		284	jmp .opt_loop
1733	hidnplayr	285
		286	.no_options:
		287
		288
		289
		290
		291
		292
		293	;-----------------------------------------------------------------------
		294	; Time to do some header prediction (Original Principle by Van Jacobson)
		295
		296	; There are two common cases for an uni-directional data transfer.
		297	;
		298	; General rule: the packets has no control flags, is in-sequence,
		299	; window width didnt change and we're not retransmitting.
		300	;
		301	; Second rules:
		302	; - If the length is 0 and the ACK moved forward, we're the sender side of the transfer.
		303	; In this case we'll free the ACK'ed data and notify higher levels that we have free space in buffer
		304	;
		305	; - If the length is not 0 and the ACK didn't move, we're the receiver side of the transfer.
		306	; If the packets are in order (data queue is empty), add the data to the socket buffer and request a delayed ACK
		307
2390	hidnplayr	308	cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED
		309	jnz .not_uni_xfer
1733	hidnplayr	310
2390	hidnplayr	311	test [edx + TCP_header.Flags], TH_SYN + TH_FIN + TH_RST + TH_URG
		312	jnz .not_uni_xfer
1733	hidnplayr	313
2390	hidnplayr	314	test [edx + TCP_header.Flags], TH_ACK
		315	jz .not_uni_xfer
1733	hidnplayr	316
2390	hidnplayr	317	mov eax, [edx + TCP_header.SequenceNumber]
		318	cmp eax, [ebx + TCP_SOCKET.RCV_NXT]
		319	jne .not_uni_xfer
1733	hidnplayr	320
2390	hidnplayr	321	mov eax, dword [edx + TCP_header.Window]
		322	cmp eax, [ebx + TCP_SOCKET.SND_WND]
		323	jne .not_uni_xfer
1733	hidnplayr	324
2390	hidnplayr	325	mov eax, [ebx + TCP_SOCKET.SND_NXT]
		326	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
		327	jne .not_uni_xfer
1733	hidnplayr	328
		329	;---------------------------------------
		330	; check if we are sender in the uni-xfer
		331
		332	; If the following 4 conditions are all true, this segment is a pure ACK.
		333	;
		334	; - The segment contains no data.
2390	hidnplayr	335	test ecx, ecx
		336	jnz .not_sender
1733	hidnplayr	337
		338	; - The congestion window is greater than or equal to the current send window.
		339	; 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.
2390	hidnplayr	340	mov eax, [ebx + TCP_SOCKET.SND_CWND]
		341	cmp eax, [ebx + TCP_SOCKET.SND_WND]
		342	jb .not_uni_xfer
1733	hidnplayr	343
		344	; - The acknowledgment field in the segment is less than or equal to the maximum sequence number sent.
2390	hidnplayr	345	mov eax, [edx + TCP_header.AckNumber]
		346	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
		347	ja .not_uni_xfer
1733	hidnplayr	348
		349	; - The acknowledgment field in the segment is greater than the largest unacknowledged sequence number.
2390	hidnplayr	350	sub eax, [ebx + TCP_SOCKET.SND_UNA]
		351	jbe .not_uni_xfer
1733	hidnplayr	352
2390	hidnplayr	353	DEBUGF 1,"Header prediction: we are sender\n"
1733	hidnplayr	354
		355	;---------------------------------
		356	; Packet is a pure ACK, process it
		357
		358	; Update RTT estimators
		359
1763	hidnplayr	360	;;; TODO
		361
1733	hidnplayr	362	; Delete acknowledged bytes from send buffer
2390	hidnplayr	363	pusha
		364	mov ecx, eax
		365	lea eax, [ebx + STREAM_SOCKET.snd]
		366	call SOCKET_ring_free
		367	popa
1733	hidnplayr	368
		369	; update window pointers
2390	hidnplayr	370	mov eax, [edx + TCP_header.AckNumber]
		371	mov [ebx + TCP_SOCKET.SND_UNA], eax
1733	hidnplayr	372
		373	; Stop retransmit timer
2390	hidnplayr	374	mov [ebx + TCP_SOCKET.timer_retransmission], 0
1733	hidnplayr	375
		376	; Awaken waiting processes
2402	hidnplayr	377	pusha
		378	lea ecx, [ebx + SOCKET.mutex]
		379	call mutex_unlock
		380	popa
		381
2390	hidnplayr	382	mov eax, ebx
		383	call SOCKET_notify_owner
1733	hidnplayr	384
1763	hidnplayr	385	; Generate more output
2390	hidnplayr	386	call TCP_output
1733	hidnplayr	387
2390	hidnplayr	388	jmp .drop_not_locked
1763	hidnplayr	389
1733	hidnplayr	390	;-------------------------------------------------
		391	; maybe we are the receiver in the uni-xfer then..
		392
		393	.not_sender:
		394	; - The amount of data in the segment is greater than 0 (data count is in ecx)
		395
		396	; - The acknowledgment field equals the largest unacknowledged sequence number. This means no data is acknowledged by this segment.
2390	hidnplayr	397	mov eax, [edx + TCP_header.AckNumber]
		398	cmp eax, [ebx + TCP_SOCKET.SND_UNA]
		399	jne .not_uni_xfer
1733	hidnplayr	400
		401	; - The reassembly list of out-of-order segments for the connection is empty (seg_next equals tp).
		402
		403	;;; TODO
		404
2390	hidnplayr	405	jnz .not_uni_xfer
1733	hidnplayr	406
		407	; Complete processing of received data
		408
2390	hidnplayr	409	DEBUGF 1,"header prediction: we are receiver\nreceiving %u bytes of data\n", ecx
1733	hidnplayr	410
2390	hidnplayr	411	add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied
1763	hidnplayr	412
2390	hidnplayr	413	movzx esi, [edx + TCP_header.DataOffset]
		414	add esi, edx
		415	lea eax, [ebx + STREAM_SOCKET.rcv]
		416	call SOCKET_ring_write ; Add the data to the socket buffer
1733	hidnplayr	417
2390	hidnplayr	418	mov eax, ebx
		419	call SOCKET_notify_owner
1733	hidnplayr	420
2390	hidnplayr	421	or [ebx + TCP_SOCKET.t_flags], TF_DELACK ; Set delayed ack flag
1733	hidnplayr	422
2390	hidnplayr	423	jmp .drop
1733	hidnplayr	424
		425
		426
		427
		428
		429
		430	;--------------------------------------------------
		431	; Header prediction failed, do it the slow way
		432
		433	.not_uni_xfer:
		434
2390	hidnplayr	435	DEBUGF 1,"Header prediction failed\n"
1733	hidnplayr	436
		437	; Calculate receive window size
		438
2362	hidnplayr	439	; mov eax, [ebx + STREAM_SOCKET.rcv.size]
2305	hidnplayr	440	; neg eax
		441	; add eax, SOCKETBUFFSIZE
		442	; mov edx, [ebx + TCP_SOCKET.RCV_ADV]
		443	; sub edx, [ebx + TCP_SOCKET.RCV_NXT]
		444	; cmp eax, edx
		445	; jae @f
		446	; mov eax, edx
		447	; @@:
1733	hidnplayr	448
2390	hidnplayr	449	cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN
		450	je .LISTEN
1733	hidnplayr	451
2390	hidnplayr	452	cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_SENT
		453	je .SYN_SENT
1733	hidnplayr	454
2390	hidnplayr	455	jmp .NOT_LISTEN_OR_SYN_SENT
1733	hidnplayr	456
		457
		458
		459	;-------------
		460	; Passive Open
		461
		462	align 4
2555	hidnplayr	463	.LISTEN:
1733	hidnplayr	464
2390	hidnplayr	465	DEBUGF 1,"TCP state: listen\n"
1733	hidnplayr	466
2390	hidnplayr	467	test [edx + TCP_header.Flags], TH_RST ;;; TODO: kill new socket on error
		468	jnz .drop
1733	hidnplayr	469
2390	hidnplayr	470	test [edx + TCP_header.Flags], TH_ACK
		471	jnz .drop_with_reset
1733	hidnplayr	472
2390	hidnplayr	473	test [edx + TCP_header.Flags], TH_SYN
		474	jz .drop
1733	hidnplayr	475
		476	;;; TODO: check if it's a broadcast or multicast, and drop if so
		477
2555	hidnplayr	478	push dword [edi] ; Ipv4 source addres
2390	hidnplayr	479	pop [ebx + IP_SOCKET.RemoteIP]
1733	hidnplayr	480
2390	hidnplayr	481	push [edx + TCP_header.SourcePort]
		482	pop [ebx + TCP_SOCKET.RemotePort]
1733	hidnplayr	483
2390	hidnplayr	484	push [edx + TCP_header.SequenceNumber]
		485	pop [ebx + TCP_SOCKET.IRS]
1733	hidnplayr	486
2390	hidnplayr	487	push [TCP_sequence_num] ;;;;;
		488	add [TCP_sequence_num], 64000 / 2
		489	pop [ebx + TCP_SOCKET.ISS]
1733	hidnplayr	490
2390	hidnplayr	491	push [ebx + TCP_SOCKET.ISS]
		492	pop [ebx + TCP_SOCKET.SND_NXT]
1733	hidnplayr	493
2390	hidnplayr	494	TCP_sendseqinit ebx
		495	TCP_rcvseqinit ebx
1733	hidnplayr	496
2390	hidnplayr	497	mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
		498	mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		499	mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval ;;;; macro
1838	hidnplayr	500
2390	hidnplayr	501	lea eax, [ebx + STREAM_SOCKET.snd]
		502	call SOCKET_ring_create
1733	hidnplayr	503
2390	hidnplayr	504	lea eax, [ebx + STREAM_SOCKET.rcv]
		505	call SOCKET_ring_create
1733	hidnplayr	506
1838	hidnplayr	507	;;; call SOCKET_notify_owner
1733	hidnplayr	508
2390	hidnplayr	509	jmp .trim_then_step6
		510
1733	hidnplayr	511
		512
		513
		514
		515
		516
		517
		518
1838	hidnplayr	519
1733	hidnplayr	520	;------------
		521	; Active Open
		522
		523	align 4
		524	.SYN_SENT:
		525
2390	hidnplayr	526	DEBUGF 1,"TCP state: syn_sent\n"
1733	hidnplayr	527
2390	hidnplayr	528	test [edx + TCP_header.Flags], TH_ACK
		529	jz @f
1733	hidnplayr	530
2390	hidnplayr	531	mov eax, [edx + TCP_header.AckNumber]
		532	cmp eax, [ebx + TCP_SOCKET.ISS]
		533	jbe .drop_with_reset
1733	hidnplayr	534
2390	hidnplayr	535	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
		536	ja .drop_with_reset
1733	hidnplayr	537	@@:
		538
2390	hidnplayr	539	test [edx + TCP_header.Flags], TH_RST
		540	jz @f
1733	hidnplayr	541
2390	hidnplayr	542	test [edx + TCP_header.Flags], TH_ACK
		543	jz .drop
1733	hidnplayr	544
2390	hidnplayr	545	mov eax, ebx
		546	mov ebx, ECONNREFUSED
		547	call TCP_drop
1733	hidnplayr	548
2390	hidnplayr	549	jmp .drop
1733	hidnplayr	550	@@:
		551
2390	hidnplayr	552	test [edx + TCP_header.Flags], TH_SYN
		553	jz .drop
1733	hidnplayr	554
		555	; at this point, segment seems to be valid
		556
2390	hidnplayr	557	test [edx + TCP_header.Flags], TH_ACK
		558	jz .no_syn_ack
1733	hidnplayr	559
		560	; now, process received SYN in response to an active open
		561
2390	hidnplayr	562	mov eax, [edx + TCP_header.AckNumber]
		563	mov [ebx + TCP_SOCKET.SND_UNA], eax
		564	cmp eax, [ebx + TCP_SOCKET.SND_NXT]
		565	jbe @f
		566	mov [ebx + TCP_SOCKET.SND_NXT], eax
1733	hidnplayr	567	@@:
		568
		569	.no_syn_ack:
		570
2390	hidnplayr	571	mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; disable retransmission
1733	hidnplayr	572
2390	hidnplayr	573	push [edx + TCP_header.SequenceNumber]
		574	pop [ebx + TCP_SOCKET.IRS]
1733	hidnplayr	575
2390	hidnplayr	576	TCP_rcvseqinit ebx
1733	hidnplayr	577
2390	hidnplayr	578	or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
1733	hidnplayr	579
2390	hidnplayr	580	mov eax, [ebx + TCP_SOCKET.SND_UNA]
		581	cmp eax, [ebx + TCP_SOCKET.ISS]
		582	jbe .simultaneous_open
1733	hidnplayr	583
2390	hidnplayr	584	test [edx + TCP_header.Flags], TH_ACK
		585	jz .simultaneous_open
1733	hidnplayr	586
2390	hidnplayr	587	DEBUGF 1,"TCP: active open\n"
1733	hidnplayr	588
		589	;;; TODO: update stats
		590
		591	; set socket state to connected
		592
2390	hidnplayr	593	mov [ebx + SOCKET.state],1 ;;;; FIXME
1733	hidnplayr	594
2390	hidnplayr	595	mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED
1733	hidnplayr	596
		597	;;; TODO: check if we should scale the connection (567-572)
		598	;;; TODO: update RTT estimators
		599
2390	hidnplayr	600	jmp .trim_then_step6
1733	hidnplayr	601
		602	.simultaneous_open:
		603
2390	hidnplayr	604	DEBUGF 1,"TCP: simultaneous open\n"
1733	hidnplayr	605	; We have received a syn but no ACK, so we are having a simultaneous open..
2390	hidnplayr	606	mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
1733	hidnplayr	607
		608
		609
		610
		611
		612
		613
		614	;-------------------------------------
		615	; Common processing for receipt of SYN
		616
		617	.trim_then_step6:
		618
2390	hidnplayr	619	inc [edx + TCP_header.SequenceNumber]
1733	hidnplayr	620
		621	;;; TODO: Drop any received data that follows receive window (590)
		622
2390	hidnplayr	623	mov eax, [edx + TCP_header.SequenceNumber]
		624	mov [ebx + TCP_SOCKET.RCV_UP], eax
		625	dec eax
		626	mov [ebx + TCP_SOCKET.SND_WL1], eax
1733	hidnplayr	627
2390	hidnplayr	628	jmp .ack_processed
1733	hidnplayr	629
		630
		631
		632
		633
		634
		635
		636
		637	.NOT_LISTEN_OR_SYN_SENT:
		638
2390	hidnplayr	639	DEBUGF 1,"Slow TCP input: not listen or syn_sent state\n"
1733	hidnplayr	640
		641	;--------------------------------------------
		642	; Protection Against Wrapped Sequence Numbers
		643
		644	; First, check if timestamp is present
		645
1763	hidnplayr	646	;;;; TODO 602
1733	hidnplayr	647
		648	; Then, check if at least some bytes of data are within window
		649
		650	;;;; TODO
		651
		652
		653
		654
		655
		656
		657
		658
		659	;----------------------------
		660	; trim any data not in window
		661
		662	; check for duplicate data at beginning of segment
		663
2390	hidnplayr	664	mov eax, [ebx + TCP_SOCKET.RCV_NXT]
		665	sub eax, [edx + TCP_header.SequenceNumber]
		666	jbe .no_duplicate
1733	hidnplayr	667
2390	hidnplayr	668	DEBUGF 1,"Uh oh.. %u bytes of duplicate data!\n", eax
1763	hidnplayr	669
2390	hidnplayr	670	test [edx + TCP_header.Flags], TH_SYN
		671	jz .no_dup_syn
1733	hidnplayr	672
		673	; remove duplicate syn
		674
2390	hidnplayr	675	and [edx + TCP_header.Flags], not (TH_SYN)
		676	inc [edx + TCP_header.SequenceNumber]
1733	hidnplayr	677
2390	hidnplayr	678	cmp [edx + TCP_header.UrgentPointer], 1
		679	jbe @f
		680	dec [edx + TCP_header.UrgentPointer]
		681	jmp .dup_syn
1733	hidnplayr	682	@@:
2390	hidnplayr	683	and [edx + TCP_header.Flags], not (TH_URG)
1838	hidnplayr	684	.dup_syn:
2390	hidnplayr	685	dec eax
1763	hidnplayr	686	.no_dup_syn:
1733	hidnplayr	687
		688	; eax holds number of bytes to drop
		689
		690	; Check for entire duplicate packet
		691
2390	hidnplayr	692	cmp eax, ecx
		693	jae .duplicate
1733	hidnplayr	694
2390	hidnplayr	695	DEBUGF 1,"Going to drop %u out of %u bytes\n", eax, ecx
1830	hidnplayr	696
1733	hidnplayr	697	;;; TODO: apply figure 28.30
		698
		699	; Check for duplicate FIN
		700
2390	hidnplayr	701	test [edx + TCP_header.Flags], TH_FIN
		702	jz @f
		703	inc ecx
		704	cmp eax, ecx
		705	dec ecx
		706	jne @f
1733	hidnplayr	707
2390	hidnplayr	708	mov eax, ecx
		709	and [edx + TCP_header.Flags], not TH_FIN
		710	or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		711	jmp .no_duplicate
1733	hidnplayr	712	@@:
		713
		714	; Handle the case when a bound socket connects to itself
		715	; Allow packets with a SYN and an ACKto continue with the processing
		716
		717	;-------------------------------------
		718	; Generate duplicate ACK if nescessary
		719
		720	; This code also handles simultaneous half-open or self-connects
		721
2390	hidnplayr	722	test eax, eax
		723	jnz .drop_after_ack
1733	hidnplayr	724
2390	hidnplayr	725	cmp [edx + TCP_header.Flags], TH_ACK
		726	jz .drop_after_ack
1733	hidnplayr	727
		728	.duplicate:
		729
2390	hidnplayr	730	DEBUGF 1,"Duplicate received\n"
1733	hidnplayr	731
		732	;----------------------------------------
		733	; Update statistics for duplicate packets
		734
		735	;;; TODO
		736
2390	hidnplayr	737	jmp .drop_after_ack
1733	hidnplayr	738
		739	.no_duplicate:
		740
		741	;-----------------------------------------------
		742	; Remove duplicate data and update urgent offset
		743
2390	hidnplayr	744	add [edx + TCP_header.SequenceNumber], eax
1733	hidnplayr	745
		746	;;; TODO
		747
2390	hidnplayr	748	sub [edx + TCP_header.UrgentPointer], ax
		749	ja @f
1733	hidnplayr	750
2390	hidnplayr	751	and [edx + TCP_header.Flags], not (TH_URG)
		752	mov [edx + TCP_header.UrgentPointer], 0
1733	hidnplayr	753	@@:
		754
		755	;--------------------------------------------------
		756	; Handle data that arrives after process terminates
		757
2390	hidnplayr	758	cmp [ebx + SOCKET.PID], 0
		759	ja @f
1733	hidnplayr	760
2390	hidnplayr	761	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT
		762	jbe @f
1733	hidnplayr	763
2390	hidnplayr	764	test ecx, ecx
		765	jz @f
1733	hidnplayr	766
		767	;;; Close the socket
		768	;;; update stats
		769
2390	hidnplayr	770	jmp .drop_with_reset
1733	hidnplayr	771	@@:
		772
		773	;----------------------------------------
		774	; Remove data beyond right edge of window
		775
2390	hidnplayr	776	mov eax, [edx + TCP_header.SequenceNumber]
		777	add eax, ecx
		778	sub eax, [ebx + TCP_SOCKET.RCV_NXT]
		779	sub ax, [ebx + TCP_SOCKET.RCV_WND]
1733	hidnplayr	780
		781	; eax now holds the number of bytes to drop
		782
2390	hidnplayr	783	jbe .no_excess_data
1733	hidnplayr	784
		785	;;; TODO: update stats
		786
2390	hidnplayr	787	cmp eax, ecx
		788	jb .dont_drop_all
1733	hidnplayr	789
		790	;;; TODO 700-736
		791
		792	.dont_drop_all:
		793
		794	.no_excess_data:
		795
		796
		797
		798
		799
		800
		801
		802
		803	;-----------------
		804	; Record timestamp
		805
		806	;;; TODO 737-746
		807
		808
		809
		810
		811
		812	;------------------
		813	; Process RST flags
		814
2390	hidnplayr	815	test [edx + TCP_header.Flags], TH_RST
		816	jz .rst_skip
1733	hidnplayr	817
2390	hidnplayr	818	DEBUGF 1,"Got an RST flag"
1733	hidnplayr	819
2390	hidnplayr	820	mov eax, [ebx + TCP_SOCKET.t_state]
		821	shl eax, 2
		822	jmp dword [eax + .rst_sw_list]
1733	hidnplayr	823
		824	.rst_sw_list:
2390	hidnplayr	825	dd .rst_skip ;TCPS_CLOSED
		826	dd .rst_skip ;TCPS_LISTEN
		827	dd .rst_skip ;TCPS_SYN_SENT
		828	dd .econnrefused ;TCPS_SYN_RECEIVED
		829	dd .econnreset ;TCPS_ESTABLISHED
		830	dd .econnreset ;TCPS_CLOSE_WAIT
		831	dd .econnreset ;TCPS_FIN_WAIT_1
		832	dd .rst_close ;TCPS_CLOSING
		833	dd .rst_close ;TCPS_LAST_ACK
		834	dd .econnreset ;TCPS_FIN_WAIT_2
		835	dd .rst_close ;TCPS_TIMED_WAIT
1733	hidnplayr	836
		837	.econnrefused:
2390	hidnplayr	838	DEBUGF 1,"Connection refused"
1733	hidnplayr	839
2390	hidnplayr	840	mov [ebx + SOCKET.errorcode], ECONNREFUSED
		841	jmp .close
1733	hidnplayr	842
		843	.econnreset:
2390	hidnplayr	844	DEBUGF 1,"Connection reset"
1733	hidnplayr	845
2390	hidnplayr	846	mov [ebx + SOCKET.errorcode], ECONNRESET
1733	hidnplayr	847
1831	hidnplayr	848	.close:
2390	hidnplayr	849	DEBUGF 1,"Closing connection"
1733	hidnplayr	850
2390	hidnplayr	851	mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSED
		852	;;; TODO: update stats
		853	mov eax, ebx
		854	call TCP_close
		855	jmp .drop
1733	hidnplayr	856
		857	.rst_close:
2390	hidnplayr	858	DEBUGF 1,"Closing with reset\n"
1733	hidnplayr	859
2390	hidnplayr	860	mov eax, ebx
		861	call TCP_close
		862	jmp .drop
1733	hidnplayr	863
		864
		865
		866
		867
		868
		869
1763	hidnplayr	870	.rst_skip:
1733	hidnplayr	871
1763	hidnplayr	872
1733	hidnplayr	873	;--------------------------------------
		874	; handle SYN-full and ACK-less segments
		875
2390	hidnplayr	876	test [edx + TCP_header.Flags], TH_SYN
		877	jz @f
1733	hidnplayr	878
2390	hidnplayr	879	mov eax, ebx
		880	mov ebx, ECONNRESET
		881	call TCP_drop
		882	jmp .drop_with_reset
1733	hidnplayr	883
2390	hidnplayr	884	test [edx + TCP_header.Flags], TH_ACK
		885	jz .drop
1733	hidnplayr	886	@@:
		887
		888
		889
		890
		891
		892
		893
		894	;---------------
		895	; ACK processing
		896
2390	hidnplayr	897	cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED
		898	jnz .no_syn_rcv
1733	hidnplayr	899
2390	hidnplayr	900	DEBUGF 1,"TCP state = syn received\n"
1733	hidnplayr	901
2390	hidnplayr	902	mov eax, [edx + TCP_header.AckNumber]
		903	cmp [ebx + TCP_SOCKET.SND_UNA], eax
		904	ja .drop_with_reset
		905	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
		906	ja .drop_with_reset
1733	hidnplayr	907
2309	hidnplayr	908	;;; TODO: update stats
		909
2390	hidnplayr	910	mov eax, ebx
		911	call SOCKET_is_connected
		912	mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED
1831	hidnplayr	913
		914	; Do window scaling?
		915
2390	hidnplayr	916	test [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE
		917	jz @f
		918	test [ebx + TCP_SOCKET.t_flags], TF_REQ_SCALE
		919	jz @f
1831	hidnplayr	920
2390	hidnplayr	921	push word [ebx + TCP_SOCKET.requested_s_scale] ; Set send and receive scale factors to the received values
		922	pop word [ebx + TCP_SOCKET.SND_SCALE]
1831	hidnplayr	923	@@:
		924
2309	hidnplayr	925	;;; TODO: copy the data (if any) into the socket
1831	hidnplayr	926
2390	hidnplayr	927	mov eax, [edx + TCP_header.SequenceNumber]
		928	dec eax
		929	mov [ebx + TCP_SOCKET.SND_WL1], eax
		930	jmp .not_dup_ack
1831	hidnplayr	931
1733	hidnplayr	932	.no_syn_rcv:
		933
		934	; check for duplicate ACK
		935
2390	hidnplayr	936	mov eax, [edx + TCP_header.AckNumber]
		937	cmp eax, [ebx + TCP_SOCKET.SND_UNA]
		938	ja .not_dup_ack
1733	hidnplayr	939
2390	hidnplayr	940	test ecx, ecx
		941	jnz .reset_dupacks
1733	hidnplayr	942
2390	hidnplayr	943	mov eax, dword [edx + TCP_header.Window]
		944	cmp eax, [ebx + TCP_SOCKET.SND_WND]
		945	jne .reset_dupacks
1733	hidnplayr	946
2390	hidnplayr	947	DEBUGF 1,"Processing a duplicate ACK..\n"
1733	hidnplayr	948
2390	hidnplayr	949	cmp [ebx + TCP_SOCKET.timer_retransmission], 10000 ;;;; FIXME
		950	ja @f
1733	hidnplayr	951
2390	hidnplayr	952	mov eax, [edx + TCP_header.AckNumber]
		953	cmp eax, [ebx + TCP_SOCKET.SND_UNA]
		954	je .dup_ack
1763	hidnplayr	955
		956	@@:
2390	hidnplayr	957	mov [ebx + TCP_SOCKET.t_dupacks], 0
		958	jmp .not_dup_ack
1763	hidnplayr	959
		960	.dup_ack:
2390	hidnplayr	961	inc [ebx + TCP_SOCKET.t_dupacks]
		962	cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh
		963	jne .no_re_xmit
1763	hidnplayr	964
2390	hidnplayr	965	push [ebx + TCP_SOCKET.SND_NXT] ; >>>>
1763	hidnplayr	966
2390	hidnplayr	967	mov eax, [ebx + TCP_SOCKET.SND_WND]
		968	cmp eax, [ebx + TCP_SOCKET.SND_CWND]
		969	cmovg eax, [ebx + TCP_SOCKET.SND_CWND]
		970	shr eax, 1
		971	push edx
		972	xor edx, edx
		973	div [ebx + TCP_SOCKET.t_maxseg]
		974	cmp eax, 2
		975	jae @f
		976	mov ax, 2
1763	hidnplayr	977	@@:
2390	hidnplayr	978	mul [ebx + TCP_SOCKET.t_maxseg]
		979	pop edx
		980	mov [ebx + TCP_SOCKET.SND_SSTHRESH], eax
1763	hidnplayr	981
2390	hidnplayr	982	mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; turn off retransmission timer
		983	mov [ebx + TCP_SOCKET.t_rtt], 0
		984	mov eax, [edx + TCP_header.AckNumber]
		985	mov [ebx + TCP_SOCKET.SND_NXT], eax
		986	mov eax, [ebx + TCP_SOCKET.t_maxseg]
		987	mov [ebx + TCP_SOCKET.SND_CWND], eax
1763	hidnplayr	988
2390	hidnplayr	989	mov eax, ebx
		990	call TCP_output ; retransmit missing segment
1763	hidnplayr	991
2390	hidnplayr	992	push edx
		993	xor edx, edx
		994	mov eax, [ebx + TCP_SOCKET.t_maxseg]
		995	mul [ebx + TCP_SOCKET.t_dupacks]
		996	pop edx
		997	add eax, [ebx + TCP_SOCKET.SND_SSTHRESH]
		998	mov [ebx + TCP_SOCKET.SND_CWND], eax
1763	hidnplayr	999
2390	hidnplayr	1000	pop eax ; <<<<
		1001	cmp eax, [ebx + TCP_SOCKET.SND_NXT]
		1002	jb @f
		1003	mov [ebx + TCP_SOCKET.SND_NXT], eax
1763	hidnplayr	1004	@@:
		1005
2390	hidnplayr	1006	jmp .drop
1733	hidnplayr	1007
		1008
1763	hidnplayr	1009	.no_re_xmit:
2390	hidnplayr	1010	jbe .not_dup_ack
1733	hidnplayr	1011
2390	hidnplayr	1012	DEBUGF 1,"Increasing congestion window\n"
1733	hidnplayr	1013
2390	hidnplayr	1014	mov eax, [ebx + TCP_SOCKET.t_maxseg]
		1015	add [ebx + TCP_SOCKET.SND_CWND], eax
1733	hidnplayr	1016
2390	hidnplayr	1017	mov eax, ebx
		1018	call TCP_output
1733	hidnplayr	1019
2390	hidnplayr	1020	jmp .drop
1733	hidnplayr	1021
		1022
		1023
1763	hidnplayr	1024
		1025
		1026
		1027	.not_dup_ack:
		1028
1733	hidnplayr	1029	;-------------------------------------------------
		1030	; If the congestion window was inflated to account
		1031	; for the other side's cached packets, retract it
		1032
2390	hidnplayr	1033	mov eax, [ebx + TCP_SOCKET.SND_SSTHRESH]
		1034	cmp eax, [ebx + TCP_SOCKET.SND_CWND]
		1035	ja @f
		1036	cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh
		1037	jbe @f
		1038	mov [ebx + TCP_SOCKET.SND_CWND], eax
1763	hidnplayr	1039	@@:
1733	hidnplayr	1040
2390	hidnplayr	1041	mov [ebx + TCP_SOCKET.t_dupacks], 0
1733	hidnplayr	1042
2390	hidnplayr	1043	mov eax, [edx + TCP_header.AckNumber]
		1044	cmp eax, [ebx + TCP_SOCKET.SND_MAX]
		1045	jbe @f
1733	hidnplayr	1046
2390	hidnplayr	1047	;;; TODO: update stats
		1048	jmp .drop_after_ack
1733	hidnplayr	1049
1763	hidnplayr	1050	@@:
1733	hidnplayr	1051
2390	hidnplayr	1052	mov edi, [edx + TCP_header.AckNumber]
		1053	sub edi, [ebx + TCP_SOCKET.SND_UNA] ; now we got the number of acked bytes in edi
1733	hidnplayr	1054
2390	hidnplayr	1055	;;; TODO: update stats
1733	hidnplayr	1056
		1057
2390	hidnplayr	1058	DEBUGF 1,"We have an acceptable ACK of %x bytes\n", esi
1763	hidnplayr	1059
		1060
		1061
		1062
		1063
		1064
1733	hidnplayr	1065	;------------------------------------------
		1066	; RTT measurements and retransmission timer
		1067
2390	hidnplayr	1068	;;;;; 912 - 926
1733	hidnplayr	1069
2390	hidnplayr	1070	mov [ebx + TCP_SOCKET.timer_retransmission], 0
1733	hidnplayr	1071
2390	hidnplayr	1072	mov eax, [ebx + TCP_SOCKET.SND_MAX]
		1073	cmp eax, [edx + TCP_header.AckNumber]
		1074	je .all_outstanding
		1075	mov [ebx + TCP_SOCKET.timer_retransmission], 120 ;;;; TODO: correct this value (use a macro for it)
1733	hidnplayr	1076	.all_outstanding:
		1077
		1078
		1079
		1080
		1081
		1082
		1083
		1084	;-------------------------------------------
		1085	; Open congestion window in response to ACKs
		1086
2390	hidnplayr	1087	mov esi, [ebx + TCP_SOCKET.SND_CWND]
		1088	mov eax, [ebx + TCP_SOCKET.t_maxseg]
1733	hidnplayr	1089
2390	hidnplayr	1090	cmp esi, [ebx + TCP_SOCKET.SND_SSTHRESH]
		1091	jbe @f
		1092	push edx
		1093	push eax
		1094	mul eax
		1095	div esi
		1096	pop edx
		1097	shr edx, 3
		1098	add eax, edx
		1099	pop edx
1763	hidnplayr	1100	@@:
1733	hidnplayr	1101
2390	hidnplayr	1102	add esi, eax
1733	hidnplayr	1103
2390	hidnplayr	1104	push ecx
		1105	mov cl, [ebx + TCP_SOCKET.SND_SCALE]
		1106	mov eax, TCP_max_win
		1107	shl eax, cl
		1108	pop ecx
1733	hidnplayr	1109
2390	hidnplayr	1110	cmp esi, eax
		1111	cmovg esi, eax
		1112	mov [ebx + TCP_SOCKET.SND_CWND], esi
1733	hidnplayr	1113
		1114
		1115
		1116
1763	hidnplayr	1117
		1118
		1119
1733	hidnplayr	1120	;------------------------------------------
		1121	; Remove acknowledged data from send buffer
		1122
2390	hidnplayr	1123	push ecx edx ebx
		1124	mov ecx, edi
		1125	lea eax, [ebx + STREAM_SOCKET.snd]
		1126	call SOCKET_ring_free
		1127	pop ebx
		1128	sub [ebx + TCP_SOCKET.SND_WND], ecx
		1129	pop edx ecx
1733	hidnplayr	1130
		1131	; Wake up process waiting on send buffer
		1132
2390	hidnplayr	1133	mov eax, ebx
		1134	call SOCKET_notify_owner
1733	hidnplayr	1135
1831	hidnplayr	1136	; Update TCPS
1733	hidnplayr	1137
2390	hidnplayr	1138	mov eax, [edx + TCP_header.AckNumber]
		1139	mov [ebx + TCP_SOCKET.SND_UNA], eax
1733	hidnplayr	1140
2390	hidnplayr	1141	cmp eax, [ebx + TCP_SOCKET.SND_NXT]
		1142	jb @f
		1143	mov [ebx + TCP_SOCKET.SND_NXT], eax
1733	hidnplayr	1144	@@:
		1145
		1146
2390	hidnplayr	1147	;; TODO: use zero flag as 'ourfinisacked'
1733	hidnplayr	1148
		1149
		1150
		1151
		1152	; General ACK handling complete
		1153	; Now do the state-specific ones
		1154
2390	hidnplayr	1155	mov eax, [ebx + TCP_SOCKET.t_state]
		1156	jmp dword [eax*4 + .ACK_sw_list]
1733	hidnplayr	1157
		1158	.ACK_sw_list:
2390	hidnplayr	1159	dd .ack_processed ;TCPS_CLOSED
		1160	dd .ack_processed ;TCPS_LISTEN
		1161	dd .ack_processed ;TCPS_SYN_SENT
		1162	dd .ack_processed ;TCPS_SYN_RECEIVED
		1163	dd .ack_processed ;TCPS_ESTABLISHED
		1164	dd .ack_processed ;TCPS_CLOSE_WAIT
		1165	dd .ack_fw1 ;TCPS_FIN_WAIT_1
		1166	dd .ack_c ;TCPS_CLOSING
		1167	dd .ack_la ;TCPS_LAST_ACK
		1168	dd .ack_processed ;TCPS_FIN_WAIT_2
		1169	dd .ack_tw ;TCPS_TIMED_WAIT
1733	hidnplayr	1170
		1171
1772	hidnplayr	1172	.ack_fw1:
2390	hidnplayr	1173	jz .ack_processed
1733	hidnplayr	1174
2390	hidnplayr	1175	test [ebx + SOCKET.state], SS_CANTRCVMORE
		1176	jnz @f
		1177	mov eax, ebx
		1178	call SOCKET_is_disconnected
1773	hidnplayr	1179	;;; mov [ebx + TCP_SOCKET.timer_timed_wait], TCP_time_max_idle
1772	hidnplayr	1180	@@:
1733	hidnplayr	1181
2390	hidnplayr	1182	mov [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2
		1183	jmp .ack_processed
1733	hidnplayr	1184
		1185
1772	hidnplayr	1186	.ack_c:
2390	hidnplayr	1187	jz .ack_processed
1772	hidnplayr	1188
2390	hidnplayr	1189	mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT
		1190	mov eax, ebx
		1191	call TCP_cancel_timers
		1192	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1193	mov eax, ebx
		1194	call SOCKET_is_disconnected
		1195	jmp .ack_processed
1733	hidnplayr	1196
		1197
1772	hidnplayr	1198	.ack_la:
2390	hidnplayr	1199	jz .ack_processed
1733	hidnplayr	1200
1773	hidnplayr	1201
2390	hidnplayr	1202	mov eax, ebx
		1203	call TCP_close
		1204	jmp .drop
1733	hidnplayr	1205
		1206
1772	hidnplayr	1207	.ack_tw:
2390	hidnplayr	1208	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1209	jmp .drop_after_ack
1733	hidnplayr	1210
		1211
1772	hidnplayr	1212
		1213
		1214
		1215
		1216
2390	hidnplayr	1217	.reset_dupacks: ; We got a new ACK, reset duplicate ACK counter
1733	hidnplayr	1218
2390	hidnplayr	1219	mov [ebx + TCP_SOCKET.t_dupacks], 0
1733	hidnplayr	1220
2390	hidnplayr	1221	.ack_processed: ; (step 6)
1733	hidnplayr	1222
2390	hidnplayr	1223	DEBUGF 1,"ACK processed\n"
1733	hidnplayr	1224
		1225	;----------------------------------------------
		1226	; check if we need to update window information
		1227
2390	hidnplayr	1228	test [edx + TCP_header.Flags], TH_ACK
		1229	jz .no_window_update
1733	hidnplayr	1230
2390	hidnplayr	1231	mov eax, [ebx + TCP_SOCKET.SND_WL1]
		1232	cmp eax, [edx + TCP_header.SequenceNumber]
		1233	jb .update_window
		1234	ja @f
1733	hidnplayr	1235
2390	hidnplayr	1236	mov eax, [ebx + TCP_SOCKET.SND_WL2]
		1237	cmp eax, [edx + TCP_header.AckNumber]
		1238	jb .update_window
		1239	ja .no_window_update
1733	hidnplayr	1240	@@:
		1241
2390	hidnplayr	1242	mov eax, [ebx + TCP_SOCKET.SND_WL2]
		1243	cmp eax, [edx + TCP_header.AckNumber]
		1244	jne .no_window_update
1733	hidnplayr	1245
2390	hidnplayr	1246	mov eax, dword [edx + TCP_header.Window]
		1247	cmp eax, [ebx + TCP_SOCKET.SND_WND]
		1248	jbe .no_window_update
1733	hidnplayr	1249
		1250	.update_window:
		1251
2390	hidnplayr	1252	DEBUGF 1,"Updating window\n"
1733	hidnplayr	1253
		1254	; Keep track of pure window updates
		1255
		1256	; test ecx, ecx
		1257	; jz @f
		1258	;
		1259	; mov eax, [ebx + TCP_SOCKET.SND_WL2]
2305	hidnplayr	1260	; cmp eax, [edx + TCP_header.AckNumber]
1733	hidnplayr	1261	; jne @f
		1262	;
		1263	; ;; mov eax, tiwin
		1264	; cmp eax, [ebx + TCP_SOCKET.SND_WND]
2300	hidnplayr	1265	; jbe @f
1733	hidnplayr	1266	;
		1267	; ;;; update stats
		1268	;
		1269	; @@:
		1270
2390	hidnplayr	1271	mov eax, dword [edx + TCP_header.Window]
		1272	cmp eax, [ebx + TCP_SOCKET.max_sndwnd]
		1273	jbe @f
		1274	mov [ebx + TCP_SOCKET.max_sndwnd], eax
1733	hidnplayr	1275	@@:
2390	hidnplayr	1276	mov [ebx + TCP_SOCKET.SND_WND], eax
1733	hidnplayr	1277
2390	hidnplayr	1278	push [edx + TCP_header.SequenceNumber]
		1279	pop [ebx + TCP_SOCKET.SND_WL1]
1733	hidnplayr	1280
2390	hidnplayr	1281	push [edx + TCP_header.AckNumber]
		1282	pop [ebx + TCP_SOCKET.SND_WL2]
1733	hidnplayr	1283
2390	hidnplayr	1284	;;; needoutput = 1
1733	hidnplayr	1285
		1286	.no_window_update:
		1287
		1288
		1289
		1290
		1291
		1292
		1293
		1294	;-----------------
		1295	; process URG flag
		1296
2390	hidnplayr	1297	test [edx + TCP_header.Flags], TH_URG
		1298	jz .not_urgent
1733	hidnplayr	1299
2390	hidnplayr	1300	cmp [edx + TCP_header.UrgentPointer], 0
		1301	jz .not_urgent
1733	hidnplayr	1302
2390	hidnplayr	1303	cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT
		1304	je .not_urgent
1733	hidnplayr	1305
		1306	; Ignore bogus urgent offsets
		1307
2390	hidnplayr	1308	;;; 1040-1050
1733	hidnplayr	1309
2390	hidnplayr	1310	movzx eax, [edx + TCP_header.UrgentPointer]
		1311	add eax, [ebx + STREAM_SOCKET.rcv.size]
		1312	cmp eax, SOCKET_MAXDATA
		1313	jbe .not_urgent
1733	hidnplayr	1314
2390	hidnplayr	1315	mov [edx + TCP_header.UrgentPointer], 0
		1316	and [edx + TCP_header.Flags], not (TH_URG)
		1317	jmp .do_data
1733	hidnplayr	1318
		1319	.not_urgent:
		1320
		1321	; processing of received urgent pointer
		1322
2390	hidnplayr	1323	;;; TODO (1051-1093)
1733	hidnplayr	1324
		1325
		1326
		1327
		1328
		1329
		1330
		1331
		1332	;--------------------------------
		1333	; process the data in the segment
		1334
		1335	.do_data:
		1336
2390	hidnplayr	1337	DEBUGF 1,"TCP: do data (%u)\n", ecx
1733	hidnplayr	1338
2390	hidnplayr	1339	test [edx + TCP_header.Flags], TH_FIN
		1340	jnz .process_fin
1733	hidnplayr	1341
2390	hidnplayr	1342	cmp [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_1
		1343	jae .dont_do_data
1733	hidnplayr	1344
2390	hidnplayr	1345	test ecx, ecx
		1346	jz .final_processing
1733	hidnplayr	1347
2390	hidnplayr	1348	DEBUGF 1,"Processing data in segment\n"
1733	hidnplayr	1349
		1350	;; TODO: check if data is in sequence !
		1351
2390	hidnplayr	1352	movzx esi, [edx + TCP_header.DataOffset]
		1353	add esi, edx
1733	hidnplayr	1354
2390	hidnplayr	1355	or [ebx + TCP_SOCKET.t_flags], TF_DELACK
		1356	add [ebx + TCP_SOCKET.RCV_NXT], ecx
1733	hidnplayr	1357
2390	hidnplayr	1358	lea eax, [ebx + STREAM_SOCKET.rcv]
		1359	call SOCKET_ring_write
1733	hidnplayr	1360
2390	hidnplayr	1361	mov eax, ebx
		1362	call SOCKET_notify_owner
1733	hidnplayr	1363
2390	hidnplayr	1364	jmp .final_processing
1733	hidnplayr	1365
		1366
		1367	.dont_do_data:
		1368
		1369
		1370
		1371
		1372
		1373
		1374
		1375	;---------------
		1376	; FIN processing
		1377
		1378	.process_fin:
		1379
2390	hidnplayr	1380	DEBUGF 1,"Processing FIN\n"
1733	hidnplayr	1381
2390	hidnplayr	1382	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT
		1383	je .not_first_fin
		1384	cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSING
		1385	je .not_first_fin
		1386	cmp [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2
		1387	je .not_first_fin
1774	hidnplayr	1388
2390	hidnplayr	1389	DEBUGF 1,"First FIN for this connection\n"
1774	hidnplayr	1390
2390	hidnplayr	1391	mov eax, ebx
		1392	call SOCKET_cant_recv_more
1774	hidnplayr	1393
2390	hidnplayr	1394	mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		1395	inc [ebx + TCP_SOCKET.RCV_NXT]
1774	hidnplayr	1396
		1397	.not_first_fin:
2390	hidnplayr	1398	mov eax, [ebx + TCP_SOCKET.t_state]
		1399	shl eax, 2
		1400	jmp dword [eax + .FIN_sw_list]
1733	hidnplayr	1401
		1402	.FIN_sw_list:
2390	hidnplayr	1403	dd .no_fin ;TCPS_CLOSED
		1404	dd .no_fin ;TCPS_LISTEN
		1405	dd .no_fin ;TCPS_SYN_SENT
		1406	dd .fin_syn_est ;TCPS_SYN_RECEIVED
		1407	dd .fin_syn_est ;TCPS_ESTABLISHED
		1408	dd .no_fin ;TCPS_CLOSE_WAIT
		1409	dd .fin_wait1 ;TCPS_FIN_WAIT_1
		1410	dd .no_fin ;TCPS_CLOSING
		1411	dd .no_fin ;TCPS_LAST_ACK
		1412	dd .fin_wait2 ;TCPS_FIN_WAIT_2
		1413	dd .fin_timed ;TCPS_TIMED_WAIT
1733	hidnplayr	1414
		1415	.fin_syn_est:
		1416
2390	hidnplayr	1417	mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT
		1418	jmp .no_fin
1733	hidnplayr	1419
		1420	.fin_wait1:
		1421
2390	hidnplayr	1422	mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSING
		1423	jmp .no_fin
1733	hidnplayr	1424
		1425	.fin_wait2:
		1426
2390	hidnplayr	1427	mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT
		1428	mov eax, ebx
		1429	call TCP_cancel_timers
		1430	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1431	call SOCKET_is_disconnected
		1432	jmp .no_fin
1733	hidnplayr	1433
		1434	.fin_timed:
2390	hidnplayr	1435	mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL
		1436	jmp .no_fin
1733	hidnplayr	1437
		1438	.no_fin:
		1439
		1440
		1441
		1442
		1443
		1444
		1445
		1446
		1447	;-----------------
		1448	; Final processing
		1449
		1450	.final_processing:
		1451
2390	hidnplayr	1452	DEBUGF 1,"Final processing\n"
1733	hidnplayr	1453
2390	hidnplayr	1454	;;; if debug enabled, output packet
1733	hidnplayr	1455
2390	hidnplayr	1456	;test needoutput, needoutput
		1457	;jz .dumpit
1733	hidnplayr	1458
2390	hidnplayr	1459	test [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
		1460	jz .dumpit
1733	hidnplayr	1461
2390	hidnplayr	1462	DEBUGF 1,"ACK now!\n"
1733	hidnplayr	1463
2390	hidnplayr	1464	push ebx
		1465	mov eax, ebx
		1466	call TCP_output
		1467	pop ebx
1733	hidnplayr	1468
		1469	.dumpit:
		1470
2402	hidnplayr	1471	pusha
		1472	lea ecx, [ebx + SOCKET.mutex]
		1473	call mutex_unlock
		1474	popa
1733	hidnplayr	1475
2390	hidnplayr	1476	call kernel_free
		1477	add esp, 4
		1478	ret
1733	hidnplayr	1479
		1480
		1481
		1482
		1483
		1484
		1485
		1486	;------------------------------------------
		1487	; Generate an ACK, droping incoming segment
		1488
		1489	align 4
		1490	.drop_after_ack:
		1491
2390	hidnplayr	1492	DEBUGF 1,"Drop after ACK\n"
1733	hidnplayr	1493
2390	hidnplayr	1494	test [edx + TCP_header.Flags], TH_RST
		1495	jnz .drop
1733	hidnplayr	1496
2390	hidnplayr	1497	and [ebx + TCP_SOCKET.t_flags], TF_ACKNOW
1733	hidnplayr	1498
2402	hidnplayr	1499	pusha
		1500	lea ecx, [ebx + SOCKET.mutex]
		1501	call mutex_unlock
		1502	popa
1733	hidnplayr	1503
2390	hidnplayr	1504	push ebx
1838	hidnplayr	1505	; mov cl, TH_ACK
		1506	; call TCP_respond_socket
2390	hidnplayr	1507	mov eax, ebx
		1508	call TCP_output
		1509	pop ebx
1733	hidnplayr	1510
2390	hidnplayr	1511	call kernel_free
		1512	add esp, 4
		1513	ret
1733	hidnplayr	1514
		1515
		1516
		1517
		1518
		1519
		1520
		1521
		1522	;-------------------------------------------
		1523	; Generate an RST, dropping incoming segment
		1524
		1525	align 4
		1526	.drop_with_reset:
		1527
2402	hidnplayr	1528	pusha
		1529	lea ecx, [ebx + SOCKET.mutex]
		1530	call mutex_unlock
		1531	popa
1733	hidnplayr	1532
		1533	.drop_with_reset_not_locked:
		1534
2390	hidnplayr	1535	DEBUGF 1,"Drop with reset\n"
1733	hidnplayr	1536
2390	hidnplayr	1537	test [edx + TCP_header.Flags], TH_RST
		1538	jnz .drop
1733	hidnplayr	1539
2390	hidnplayr	1540	;;; if its a multicast/broadcast, also drop
1733	hidnplayr	1541
2390	hidnplayr	1542	test [edx + TCP_header.Flags], TH_ACK
		1543	jnz .respond_ack
1733	hidnplayr	1544
2390	hidnplayr	1545	test [edx + TCP_header.Flags], TH_SYN
		1546	jnz .respond_syn
1733	hidnplayr	1547
2390	hidnplayr	1548	call kernel_free
		1549	add esp, 4
		1550	ret
1733	hidnplayr	1551
		1552	.respond_ack:
		1553
2390	hidnplayr	1554	push ebx
		1555	mov cl, TH_RST
		1556	call TCP_respond_socket
		1557	pop ebx
1733	hidnplayr	1558
2390	hidnplayr	1559	jmp .destroy_new_socket
1733	hidnplayr	1560
		1561
		1562	.respond_syn:
		1563
2390	hidnplayr	1564	push ebx
		1565	mov cl, TH_RST + TH_ACK
		1566	call TCP_respond_socket
		1567	pop ebx
1733	hidnplayr	1568
2390	hidnplayr	1569	jmp .destroy_new_socket
1733	hidnplayr	1570
		1571
		1572
		1573
		1574
		1575
		1576
		1577	;-----
		1578	; Drop
		1579
		1580	align 4
		1581	.drop:
		1582
2402	hidnplayr	1583	pusha
		1584	lea ecx, [ebx + SOCKET.mutex]
		1585	call mutex_unlock
		1586	popa
1733	hidnplayr	1587
		1588	.drop_not_locked:
		1589
2390	hidnplayr	1590	DEBUGF 1,"Dropping packet\n"
1733	hidnplayr	1591
2390	hidnplayr	1592	;;;; If debugging options are enabled, output the packet somwhere
1733	hidnplayr	1593
		1594	.destroy_new_socket:
		1595
2390	hidnplayr	1596	;;;; kill the newly created socket
1733	hidnplayr	1597
2390	hidnplayr	1598	call kernel_free
		1599	add esp, 4
		1600	ret

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