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

Subversion Repositories Kolibri OS

(root)/kernel/branches/net/network/tcp_input.inc – Rev 2394