| 0,0 → 1,1663 |
|---|
| ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
| ;; ;; |
| ;; Copyright (C) KolibriOS team 2004-2013. All rights reserved. ;; |
| ;; Distributed under terms of the GNU General Public License ;; |
| ;; ;; |
| ;; Part of the TCP/IP network stack for KolibriOS ;; |
| ;; ;; |
| ;; Written by hidnplayr@kolibrios.org ;; |
| ;; ;; |
| ;; Based on the code of 4.4BSD ;; |
| ;; ;; |
| ;; GNU GENERAL PUBLIC LICENSE ;; |
| ;; Version 2, June 1991 ;; |
| ;; ;; |
| ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
| |
| $Revision: 3407 $ |
| |
| ;----------------------------------------------------------------- |
| ; |
| ; TCP_input: |
| ; |
| ; Add a segment to the incoming TCP queue |
| ; |
| ; IN: [esp] = ptr to buffer |
| ; [esp+4] = buffer size (dont care) |
| ; ebx = ptr to device struct |
| ; ecx = segment size |
| ; esi = ptr to TCP segment |
| ; edi = ptr to ipv4 source address, followed by ipv4 dest address |
| ; |
| ; OUT: / |
| ; |
| ;----------------------------------------------------------------- |
| |
| align 4 |
| TCP_input: |
| |
| ; record the current time |
| mov eax, [timer_ticks] ; in 1/100 seconds |
| mov [esp + 4], eax |
| |
| push ebx ecx esi edi ; mind the order |
| mov esi, esp |
| |
| pushf |
| cli |
| add_to_queue TCP_queue, TCP_QUEUE_SIZE, sizeof.TCP_queue_entry, .fail |
| popf |
| |
| add esp, sizeof.TCP_queue_entry |
| |
| xor edx, edx |
| mov eax, [TCP_input_event] |
| mov ebx, [eax + EVENT.id] |
| xor esi, esi |
| call raise_event |
| |
| ret |
| |
| .fail: |
| popf |
| DEBUGF 2, "TCP incoming queue is full, discarding packet!\n" |
| |
| inc [TCP_segments_missed] ; FIXME: use correct interface |
| |
| add esp, sizeof.TCP_queue_entry - 8 |
| call kernel_free |
| add esp, 4 |
| |
| ret |
| |
| |
| |
| |
| align 4 |
| TCP_process_input: |
| |
| xor esi, esi |
| mov ecx, MANUAL_DESTROY |
| call create_event |
| mov [TCP_input_event], eax |
| |
| .wait: |
| mov eax, [TCP_input_event] |
| mov ebx, [eax + EVENT.id] |
| call wait_event |
| |
| .loop: |
| get_from_queue TCP_queue, TCP_QUEUE_SIZE, sizeof.TCP_queue_entry, .wait |
| |
| push [esi + TCP_queue_entry.timestamp] |
| push [esi + TCP_queue_entry.buffer_ptr] |
| |
| mov ebx, [esi + TCP_queue_entry.device_ptr] |
| mov ecx, [esi + TCP_queue_entry.segment_size] |
| mov edi, [esi + TCP_queue_entry.ip_ptr] ; ptr to ipv4 source address, followed by ipv4 destination address |
| mov esi, [esi + TCP_queue_entry.segment_ptr] ; change esi last |
| |
| DEBUGF 1,"TCP_input: size=%u time=%d\n", ecx, [timer_ticks] |
| |
| mov edx, esi |
| |
| cmp ebx, LOOPBACK_DEVICE |
| je .checksum_ok |
| |
| ; re-calculate the checksum (if not already done by hw) |
| ; test [ebx + NET_DEVICE.hwacc], HWACC_TCP_IPv4_IN |
| ; jnz .checksum_ok |
| |
| push ecx esi |
| pushw [esi + TCP_header.Checksum] |
| mov [esi + TCP_header.Checksum], 0 |
| TCP_checksum (edi), (edi+4) |
| pop cx ; previous checksum |
| cmp cx, dx |
| pop edx ecx |
| jne .drop_no_socket |
| .checksum_ok: |
| |
| ; Verify the data offset |
| and [edx + TCP_header.DataOffset], 0xf0 ; Calculate TCP segment header size (throwing away unused reserved bits in TCP header) |
| shr [edx + TCP_header.DataOffset], 2 |
| cmp [edx + TCP_header.DataOffset], sizeof.TCP_header ; Now see if it's at least the size of a standard TCP header |
| jb .drop_no_socket ; If not, drop the packet |
| |
| movzx eax, [edx + TCP_header.DataOffset] |
| sub ecx, eax ; substract TCP header size from total segment size |
| jb .drop_no_socket ; If total segment size is less then the advertised header size, drop packet |
| DEBUGF 1,"TCP_input: %u bytes of data\n", ecx |
| |
| ;------------------------------------------- |
| ; Convert Big-endian values to little endian |
| |
| ntohd [edx + TCP_header.SequenceNumber] |
| ntohd [edx + TCP_header.AckNumber] |
| |
| ntohw [edx + TCP_header.Window] |
| ntohw [edx + TCP_header.UrgentPointer] |
| |
| ;------------------------ |
| ; Find the socket pointer |
| |
| ; IP Packet TCP Destination Port = local Port |
| ; (IP Packet SenderAddress = Remote IP) OR (Remote IP = 0) |
| ; (IP Packet TCP Source Port = remote Port) OR (remote Port = 0) |
| |
| .findpcb: |
| mov ebx, net_sockets |
| mov si, [edx + TCP_header.DestinationPort] |
| |
| .socket_loop: |
| mov ebx, [ebx + SOCKET.NextPtr] |
| or ebx, ebx |
| jz .respond_seg_reset |
| |
| cmp [ebx + SOCKET.Domain], AF_INET4 |
| jne .socket_loop |
| |
| cmp [ebx + SOCKET.Protocol], IP_PROTO_TCP |
| jne .socket_loop |
| |
| cmp [ebx + TCP_SOCKET.LocalPort], si |
| jne .socket_loop |
| |
| mov eax, [ebx + IP_SOCKET.RemoteIP] |
| cmp eax, [edi] ; Ipv4 source address |
| je @f |
| test eax, eax |
| jnz .socket_loop |
| @@: |
| |
| mov ax, [ebx + TCP_SOCKET.RemotePort] |
| cmp [edx + TCP_header.SourcePort], ax |
| je .found_socket |
| test ax, ax |
| jnz .socket_loop |
| .found_socket: ; ebx now contains the socketpointer |
| DEBUGF 1,"TCP_input: socket ptr=%x state=%u flags=%x\n", ebx, [ebx + TCP_SOCKET.t_state], [edx + TCP_header.Flags]:2 |
| |
| ;------------- |
| ; update stats |
| |
| inc [TCP_segments_rx] ; FIXME: correct interface? |
| |
| ;---------------------------- |
| ; Check if socket isnt closed |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSED |
| je .drop_no_socket |
| |
| ;---------------- |
| ; Lock the socket |
| |
| pusha |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_lock |
| popa |
| |
| DEBUGF 1,"TCP_input: socket locked\n" |
| |
| ;--------------------------- |
| ; disable all temporary bits |
| |
| mov [ebx + TCP_SOCKET.temp_bits], 0 |
| |
| ;--------------------------------------- |
| ; unscale the window into a 32 bit value |
| |
| movzx eax, [edx + TCP_header.Window] |
| push ecx |
| mov cl, [ebx + TCP_SOCKET.SND_SCALE] |
| shl eax, cl |
| mov dword [edx + TCP_header.Window], eax ; word after window is checksum, we dont need checksum anymore |
| pop ecx |
| |
| ;--------------------------------------- |
| ; Are we accepting incoming connections? |
| |
| test [ebx + SOCKET.options], SO_ACCEPTCON |
| jz .no_accept |
| |
| DEBUGF 1,"TCP_input: Accepting new connection\n" |
| |
| pusha |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| popa |
| |
| push ecx edx esi edi ;;; |
| call SOCKET_fork |
| pop edi esi edx ecx |
| |
| test eax, eax |
| jz .drop_no_socket |
| |
| mov ebx, eax |
| |
| mov [ebx + TCP_SOCKET.temp_bits], TCP_BIT_DROPSOCKET ;;; FIXME: should we take over bits from previous socket? |
| |
| push dword [edi + 4] ; Ipv4 destination addres |
| pop [ebx + IP_SOCKET.LocalIP] |
| |
| push [edx + TCP_header.DestinationPort] |
| pop [ebx + TCP_SOCKET.LocalPort] |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_LISTEN |
| .no_accept: |
| |
| |
| ;------------------------------------- |
| ; Reset idle timer and keepalive timer |
| |
| mov [ebx + TCP_SOCKET.t_idle], 0 |
| mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_idle |
| |
| ;-------------------- |
| ; Process TCP options |
| |
| push ecx |
| |
| movzx ecx, [edx + TCP_header.DataOffset] |
| cmp ecx, sizeof.TCP_header ; Does header contain any options? |
| je .no_options |
| |
| DEBUGF 1,"TCP_input: Segment has options\n" |
| |
| ;;; FIXME: for LISTEN, options should be called after we determined route, we need it for MSS |
| ;;; cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN ; no options when in listen state |
| ;;; jz .not_uni_xfer ; also no header prediction |
| |
| add ecx, edx |
| lea esi, [edx + sizeof.TCP_header] |
| |
| .opt_loop: |
| cmp esi, ecx ; are we scanning outside of header? |
| jae .no_options |
| lodsb |
| cmp al, TCP_OPT_EOL ; end of option list? |
| je .no_options |
| cmp al, TCP_OPT_NOP |
| je .opt_loop |
| cmp al, TCP_OPT_MAXSEG |
| je .opt_maxseg |
| cmp al, TCP_OPT_WINDOW |
| je .opt_window |
| cmp al, TCP_OPT_SACK_PERMIT |
| je .opt_sack_permit |
| ; cmp al, TCP_OPT_SACK |
| ; je .opt_sack |
| cmp al, TCP_OPT_TIMESTAMP |
| je .opt_timestamp |
| DEBUGF 1,"TCP_input: unknown option:%u\n", al |
| jmp .no_options ; If we reach here, some unknown options were received, skip them all! |
| |
| .opt_maxseg: |
| lodsb |
| cmp al, 4 |
| jne .no_options ; error occured, ignore all options! |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz @f |
| |
| lodsw |
| rol ax, 8 |
| DEBUGF 1,"TCP_input: Maxseg=%u\n", ax |
| call TCP_mss |
| @@: |
| jmp .opt_loop |
| |
| |
| .opt_window: |
| lodsb |
| cmp al, 3 |
| jne .no_options |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz @f |
| |
| DEBUGF 1,"TCP_input: Got window scale option\n" |
| or [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE |
| |
| lodsb |
| mov [ebx + TCP_SOCKET.SND_SCALE], al |
| ;;;;; TODO |
| |
| @@: |
| jmp .opt_loop |
| |
| |
| .opt_sack_permit: |
| lodsb |
| cmp al, 2 |
| jne .no_options |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz @f |
| |
| DEBUGF 1,"TCP_input: Selective Acknowledgement permitted\n" |
| or [ebx + TCP_SOCKET.t_flags], TF_SACK_PERMIT |
| |
| @@: |
| jmp .opt_loop |
| |
| |
| .opt_timestamp: |
| lodsb |
| cmp al, 10 ; length must be 10 |
| jne .no_options |
| |
| DEBUGF 1,"TCP_input: Got timestamp option\n" |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz @f |
| or [ebx + TCP_SOCKET.t_flags], TF_RCVD_TSTMP |
| @@: |
| |
| lodsd |
| mov [ebx + TCP_SOCKET.ts_val], eax |
| lodsd ; timestamp echo reply |
| mov [ebx + TCP_SOCKET.ts_ecr], eax |
| or [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
| |
| ; Since we have a timestamp, lets do the paws test right away! |
| |
| test [edx + TCP_header.Flags], TH_RST |
| jnz .no_paws |
| |
| mov eax, [ebx + TCP_SOCKET.ts_recent] |
| test eax, eax |
| jz .no_paws |
| cmp eax, [ebx + TCP_SOCKET.ts_val] |
| jge .no_paws |
| |
| DEBUGF 1,"TCP_input: PAWS: detected an old segment\n" |
| |
| mov eax, [esp+4+4] ; tcp_now |
| sub eax, [ebx + TCP_SOCKET.ts_recent_age] |
| |
| pop ecx |
| cmp eax, TCP_PAWS_IDLE |
| jle .drop_after_ack ; TODO: update stats |
| push ecx |
| |
| mov [ebx + TCP_SOCKET.ts_recent], 0 ; timestamp was invalid, fix it. |
| .no_paws: |
| jmp .opt_loop |
| |
| .no_options: |
| |
| pop ecx |
| |
| ;----------------------------------------------------------------------- |
| ; Time to do some header prediction (Original Principle by Van Jacobson) |
| |
| ; There are two common cases for an uni-directional data transfer. |
| ; |
| ; General rule: the packets has no control flags, is in-sequence, |
| ; window width didnt change and we're not retransmitting. |
| ; |
| ; Second rules: |
| ; - If the length is 0 and the ACK moved forward, we're the sender side of the transfer. |
| ; In this case we'll free the ACK'ed data and notify higher levels that we have free space in buffer |
| ; |
| ; - If the length is not 0 and the ACK didn't move, we're the receiver side of the transfer. |
| ; If the packets are in order (data queue is empty), add the data to the socket buffer and request a delayed ACK |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
| jnz .not_uni_xfer |
| |
| test [edx + TCP_header.Flags], TH_SYN + TH_FIN + TH_RST + TH_URG |
| jnz .not_uni_xfer |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz .not_uni_xfer |
| |
| mov eax, [edx + TCP_header.SequenceNumber] |
| cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
| jne .not_uni_xfer |
| |
| mov eax, dword [edx + TCP_header.Window] |
| cmp eax, [ebx + TCP_SOCKET.SND_WND] |
| jne .not_uni_xfer |
| |
| mov eax, [ebx + TCP_SOCKET.SND_NXT] |
| cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
| jne .not_uni_xfer |
| |
| ;--------------------------------------- |
| ; check if we are sender in the uni-xfer |
| |
| ; If the following 4 conditions are all true, this segment is a pure ACK. |
| ; |
| ; - The segment contains no data. |
| test ecx, ecx |
| jnz .not_sender |
| |
| ; - The congestion window is greater than or equal to the current send window. |
| ; 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. |
| mov eax, [ebx + TCP_SOCKET.SND_CWND] |
| cmp eax, [ebx + TCP_SOCKET.SND_WND] |
| jb .not_uni_xfer |
| |
| ; - The acknowledgment field in the segment is less than or equal to the maximum sequence number sent. |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
| ja .not_uni_xfer |
| |
| ; - The acknowledgment field in the segment is greater than the largest unacknowledged sequence number. |
| sub eax, [ebx + TCP_SOCKET.SND_UNA] |
| jbe .not_uni_xfer |
| |
| DEBUGF 1,"TCP_input: Header prediction: we are sender\n" |
| |
| ;--------------------------------- |
| ; Packet is a pure ACK, process it |
| |
| ; Delete acknowledged bytes from send buffer |
| pusha |
| mov ecx, eax |
| lea eax, [ebx + STREAM_SOCKET.snd] |
| call SOCKET_ring_free |
| popa |
| |
| ; Update RTT estimators |
| |
| test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
| jz .no_timestamp_rtt |
| mov eax, [esp + 4] ; timestamp when this segment was received |
| sub eax, [ebx + TCP_SOCKET.ts_ecr] |
| inc eax |
| call TCP_xmit_timer |
| jmp .rtt_done |
| |
| .no_timestamp_rtt: |
| cmp [ebx + TCP_SOCKET.t_rtt], 0 |
| je .rtt_done |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.t_rtseq] |
| jbe .rtt_done |
| mov eax, [ebx + TCP_SOCKET.t_rtt] |
| call TCP_xmit_timer |
| |
| .rtt_done: |
| |
| ; update window pointers |
| mov eax, [edx + TCP_header.AckNumber] |
| mov [ebx + TCP_SOCKET.SND_UNA], eax |
| |
| ; Stop retransmit timer |
| mov [ebx + TCP_SOCKET.timer_retransmission], 0 |
| |
| ; Unlock the socket |
| pusha |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| popa |
| |
| ; Awaken waiting processes |
| mov eax, ebx |
| call SOCKET_notify |
| |
| ; Generate more output |
| call TCP_output |
| |
| jmp .drop_no_socket |
| |
| ;------------------------------------------------- |
| ; maybe we are the receiver in the uni-xfer then.. |
| |
| .not_sender: |
| ; - The amount of data in the segment is greater than 0 (data count is in ecx) |
| |
| ; - The acknowledgment field equals the largest unacknowledged sequence number. This means no data is acknowledged by this segment. |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
| jne .not_uni_xfer |
| |
| ; - The reassembly list of out-of-order segments for the connection is empty (seg_next equals tp). |
| |
| ;;; TODO |
| |
| ; jnz .not_uni_xfer |
| |
| ; Complete processing of received data |
| |
| DEBUGF 1,"TCP_input: Header prediction: we are receiving %u bytes\n", ecx |
| |
| add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied |
| |
| movzx esi, [edx + TCP_header.DataOffset] |
| add esi, edx |
| lea eax, [ebx + STREAM_SOCKET.rcv] |
| call SOCKET_ring_write ; Add the data to the socket buffer |
| |
| mov eax, ebx |
| call SOCKET_notify |
| |
| or [ebx + TCP_SOCKET.t_flags], TF_DELACK ; Set delayed ack flag |
| |
| jmp .drop |
| |
| ;-------------------------------------------------- |
| ; Header prediction failed, do it the slow way |
| |
| .not_uni_xfer: |
| |
| DEBUGF 1,"TCP_input: Header prediction failed\n" |
| |
| ; Calculate receive window size |
| |
| push edx |
| mov eax, SOCKETBUFFSIZE |
| sub eax, [ebx + STREAM_SOCKET.rcv.size] |
| mov edx, [ebx + TCP_SOCKET.RCV_ADV] |
| sub edx, [ebx + TCP_SOCKET.RCV_NXT] |
| cmp eax, edx |
| jg @f |
| mov eax, edx |
| @@: |
| DEBUGF 1,"Receive window size=%d\n", eax |
| mov [ebx + TCP_SOCKET.RCV_WND], eax |
| pop edx |
| |
| ; If we are in listen or syn_sent state, go to that specific code right away |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN |
| je .LISTEN |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_SENT |
| je .SYN_SENT |
| |
| ;---------------------------- |
| ; trim any data not in window |
| |
| ; check for duplicate data at beginning of segment (635) |
| |
| mov eax, [ebx + TCP_SOCKET.RCV_NXT] |
| sub eax, [edx + TCP_header.SequenceNumber] |
| jle .no_duplicate |
| |
| DEBUGF 1,"TCP_input: %u bytes duplicate data!\n", eax |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz .no_dup_syn |
| |
| DEBUGF 1,"TCP_input: got duplicate syn\n" |
| |
| and [edx + TCP_header.Flags], not (TH_SYN) |
| inc [edx + TCP_header.SequenceNumber] |
| |
| cmp [edx + TCP_header.UrgentPointer], 1 |
| jbe @f |
| dec [edx + TCP_header.UrgentPointer] |
| jmp .dup_syn |
| @@: |
| and [edx + TCP_header.Flags], not (TH_URG) |
| .dup_syn: |
| dec eax |
| .no_dup_syn: |
| |
| ; Check for entire duplicate segment (646) |
| cmp eax, ecx ; eax holds number of bytes to drop, ecx is data size |
| jb .duplicate |
| jnz @f |
| test [edx + TCP_header.Flags], TH_FIN |
| jnz .duplicate |
| @@: |
| |
| ; Any valid FIN must be to the left of the window. |
| ; At this point the FIN must be out of sequence or a duplicate, drop it |
| and [edx + TCP_header.Flags], not TH_FIN |
| |
| ; send an ACK and resynchronize and drop any data. |
| ; But keep on processing for RST or ACK |
| DEBUGF 1, "616\n" |
| or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
| mov eax, ecx |
| ;TODO: update stats |
| |
| ;----------------------------------------------- |
| ; Remove duplicate data and update urgent offset |
| |
| .duplicate: |
| ;;; TODO: 677 |
| add [edx + TCP_header.SequenceNumber], eax |
| sub ecx, eax |
| |
| sub [edx + TCP_header.UrgentPointer], ax |
| jg @f |
| and [edx + TCP_header.Flags], not (TH_URG) |
| mov [edx + TCP_header.UrgentPointer], 0 |
| @@: |
| |
| ;-------------------------------------------------- |
| ; Handle data that arrives after process terminates (687) |
| |
| .no_duplicate: |
| cmp [ebx + SOCKET.PID], 0 |
| jne .not_terminated |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT |
| jbe .not_terminated |
| test ecx, ecx |
| jz .not_terminated |
| |
| mov eax, ebx |
| call TCP_close |
| ;;;TODO: update stats |
| jmp .respond_seg_reset |
| |
| ;---------------------------------------- |
| ; Remove data beyond right edge of window (700-736) |
| |
| .not_terminated: |
| mov eax, [edx + TCP_header.SequenceNumber] |
| add eax, ecx |
| sub eax, [ebx + TCP_SOCKET.RCV_NXT] |
| sub eax, [ebx + TCP_SOCKET.RCV_WND] ; eax now holds the number of bytes to drop |
| jle .no_excess_data |
| |
| DEBUGF 1,"%d bytes beyond right edge of window\n", eax |
| |
| ;;; TODO: update stats |
| cmp eax, ecx |
| jl .dont_drop_all |
| ; If a new connection request is received while in TIME_WAIT, drop the old connection and start over, |
| ; if the sequence numbers are above the previous ones |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz .no_new_request |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
| jne .no_new_request |
| ; mov edx, [ebx + TCP_SOCKET.RCV_NXT] |
| ; cmp edx, [edx + TCP_header.SequenceNumber] |
| ; add edx, 64000 ; TCP_ISSINCR FIXME |
| mov eax, ebx |
| call TCP_close |
| jmp .findpcb ; FIXME: skip code for unscaling window, ... |
| .no_new_request: |
| |
| ; If window is closed can only take segments at window edge, and have to drop data and PUSH from |
| ; incoming segments. Continue processing, but remember to ACK. Otherwise drop segment and ACK |
| |
| cmp [ebx + TCP_SOCKET.RCV_WND], 0 |
| jne .drop_after_ack |
| mov eax, [edx + TCP_header.SequenceNumber] |
| cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
| jne .drop_after_ack |
| |
| DEBUGF 1, "690\n" |
| or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
| ;;; TODO: update stats |
| jmp .no_excess_data |
| .dont_drop_all: |
| ;;; TODO: update stats |
| ;;; TODO: 733 |
| |
| sub ecx, eax |
| and [ebx + TCP_SOCKET.t_flags], not (TH_PUSH or TH_FIN) |
| .no_excess_data: |
| |
| ;----------------- |
| ; Record timestamp (737-746) |
| |
| ; If last ACK falls within this segments sequence numbers, record its timestamp |
| test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
| jz .no_timestamp |
| mov eax, [ebx + TCP_SOCKET.last_ack_sent] |
| sub eax, [edx + TCP_header.SequenceNumber] |
| jb .no_timestamp |
| test [ebx + TCP_header.Flags], TH_SYN or TH_FIN ; syn and fin occupy one byte |
| jz @f |
| dec eax |
| @@: |
| sub eax, ecx |
| jae .no_timestamp |
| |
| DEBUGF 1,"Recording timestamp\n" |
| |
| mov eax, [esp + 4] ; tcp_now |
| mov [ebx + TCP_SOCKET.ts_recent_age], eax |
| mov eax, [ebx + TCP_SOCKET.ts_val] |
| mov [ebx + TCP_SOCKET.ts_recent], eax |
| .no_timestamp: |
| |
| ;------------------ |
| ; Process RST flags |
| |
| test [edx + TCP_header.Flags], TH_RST |
| jz .no_rst |
| |
| DEBUGF 1,"TCP_input: Got an RST flag\n" |
| |
| mov eax, [ebx + TCP_SOCKET.t_state] |
| shl eax, 2 |
| jmp dword [eax + .rst_sw_list] |
| |
| .rst_sw_list: |
| dd .no_rst ; TCPS_CLOSED |
| dd .no_rst ; TCPS_LISTEN |
| dd .no_rst ; TCPS_SYN_SENT |
| dd .econnrefused ; TCPS_SYN_RECEIVED |
| dd .econnreset ; TCPS_ESTABLISHED |
| dd .econnreset ; TCPS_CLOSE_WAIT |
| dd .econnreset ; TCPS_FIN_WAIT_1 |
| dd .rst_close ; TCPS_CLOSING |
| dd .rst_close ; TCPS_LAST_ACK |
| dd .econnreset ; TCPS_FIN_WAIT_2 |
| dd .rst_close ; TCPS_TIMED_WAIT |
| |
| .econnrefused: |
| DEBUGF 1,"TCP_input: Connection refused\n" |
| |
| mov [ebx + SOCKET.errorcode], ECONNREFUSED |
| jmp .close |
| |
| .econnreset: |
| DEBUGF 1,"TCP_input: Connection reset\n" |
| |
| mov [ebx + SOCKET.errorcode], ECONNRESET |
| |
| .close: |
| DEBUGF 1,"TCP_input: Closing connection\n" |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSED |
| ;;; TODO: update stats (tcp drops) |
| mov eax, ebx |
| call TCP_close |
| jmp .drop_no_socket |
| |
| .rst_close: |
| DEBUGF 1,"TCP_input: Closing with reset\n" |
| |
| mov eax, ebx |
| call TCP_close |
| jmp .drop_no_socket |
| |
| .no_rst: |
| |
| ;-------------------------------------- |
| ; handle SYN-full and ACK-less segments |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz .not_syn_full |
| |
| mov eax, ebx |
| mov ebx, ECONNRESET |
| call TCP_drop |
| jmp .drop_with_reset |
| .not_syn_full: |
| |
| ;--------------- |
| ; ACK processing |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz .drop |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
| jb .ack_processed ; states: closed, listen, syn_sent |
| ja .no_syn_rcv ; established, fin_wait_1, fin_wait_2, close_wait, closing, last_ack, time_wait |
| |
| DEBUGF 1,"TCP_input: state=syn_received\n" |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp [ebx + TCP_SOCKET.SND_UNA], eax |
| ja .drop_with_reset |
| cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
| ja .drop_with_reset |
| |
| ;;; TODO: update stats |
| |
| mov eax, ebx |
| call SOCKET_is_connected |
| mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
| |
| ; Do window scaling? |
| |
| test [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE |
| jz @f |
| test [ebx + TCP_SOCKET.t_flags], TF_REQ_SCALE |
| jz @f |
| |
| push word [ebx + TCP_SOCKET.requested_s_scale] ; Set send and receive scale factors to the received values |
| pop word [ebx + TCP_SOCKET.SND_SCALE] |
| @@: |
| |
| ;;; TODO: call TCP_reassemble |
| |
| mov eax, [edx + TCP_header.SequenceNumber] |
| dec eax |
| mov [ebx + TCP_SOCKET.SND_WL1], eax |
| |
| .no_syn_rcv: |
| |
| ;------------------------- |
| ; check for duplicate ACKs |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
| ja .not_dup_ack |
| |
| test ecx, ecx |
| jnz .reset_dupacks |
| |
| mov eax, dword [edx + TCP_header.Window] |
| cmp eax, [ebx + TCP_SOCKET.SND_WND] |
| jne .reset_dupacks |
| |
| DEBUGF 1,"TCP_input: Processing duplicate ACK\n" |
| |
| ; If we have outstanding data, other than a window probe, this is a completely duplicate ACK |
| ; (window info didnt change) The ACK is the biggest we've seen and we've seen exactly our rexmt threshold of them, |
| ; assume a packet has been dropped and retransmit it. Kludge snd_nxt & the congestion window so we send only this one packet. |
| |
| cmp [ebx + TCP_SOCKET.timer_retransmission], 0 ;;;; FIXME |
| jg @f |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
| je .dup_ack |
| |
| @@: |
| mov [ebx + TCP_SOCKET.t_dupacks], 0 |
| jmp .not_dup_ack |
| |
| .dup_ack: |
| inc [ebx + TCP_SOCKET.t_dupacks] |
| cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh |
| jne .no_re_xmit |
| |
| push [ebx + TCP_SOCKET.SND_NXT] ; >>>> |
| |
| mov eax, [ebx + TCP_SOCKET.SND_WND] |
| cmp eax, [ebx + TCP_SOCKET.SND_CWND] |
| cmova eax, [ebx + TCP_SOCKET.SND_CWND] |
| shr eax, 1 |
| push edx |
| xor edx, edx |
| div [ebx + TCP_SOCKET.t_maxseg] |
| cmp eax, 2 |
| ja @f |
| xor eax, eax |
| mov al, 2 |
| @@: |
| mul [ebx + TCP_SOCKET.t_maxseg] |
| pop edx |
| mov [ebx + TCP_SOCKET.SND_SSTHRESH], eax |
| |
| mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; turn off retransmission timer |
| mov [ebx + TCP_SOCKET.t_rtt], 0 |
| mov eax, [edx + TCP_header.AckNumber] |
| mov [ebx + TCP_SOCKET.SND_NXT], eax |
| mov eax, [ebx + TCP_SOCKET.t_maxseg] |
| mov [ebx + TCP_SOCKET.SND_CWND], eax |
| |
| ; Unlock the socket |
| push ebx |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| |
| ; retransmit missing segment |
| mov eax, [esp] |
| call TCP_output |
| |
| ; Lock the socket again |
| mov ecx, [esp] |
| add ecx, SOCKET.mutex |
| call mutex_lock |
| pop ebx |
| |
| ; Continue processing |
| xor edx, edx |
| mov eax, [ebx + TCP_SOCKET.t_maxseg] |
| mul [ebx + TCP_SOCKET.t_dupacks] |
| add eax, [ebx + TCP_SOCKET.SND_SSTHRESH] |
| mov [ebx + TCP_SOCKET.SND_CWND], eax |
| |
| pop eax ; <<<< |
| cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
| jb @f |
| mov [ebx + TCP_SOCKET.SND_NXT], eax |
| @@: |
| |
| jmp .drop |
| |
| |
| .no_re_xmit: |
| jbe .not_dup_ack |
| |
| DEBUGF 1,"TCP_input: Increasing congestion window\n" |
| |
| mov eax, [ebx + TCP_SOCKET.t_maxseg] |
| add [ebx + TCP_SOCKET.SND_CWND], eax |
| |
| ; Unlock the socket |
| push ebx |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| |
| ; retransmit missing segment |
| mov eax, [esp] |
| call TCP_output |
| |
| ; Lock the socket again |
| mov ecx, [esp] |
| add ecx, SOCKET.mutex |
| call mutex_lock |
| pop ebx |
| |
| jmp .drop |
| |
| |
| .not_dup_ack: |
| |
| ;------------------------------------------------- |
| ; If the congestion window was inflated to account |
| ; for the other side's cached packets, retract it |
| |
| mov eax, [ebx + TCP_SOCKET.SND_SSTHRESH] |
| cmp eax, [ebx + TCP_SOCKET.SND_CWND] |
| ja @f |
| cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh |
| jbe @f |
| mov [ebx + TCP_SOCKET.SND_CWND], eax |
| @@: |
| |
| mov [ebx + TCP_SOCKET.t_dupacks], 0 |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
| jbe @f |
| |
| ;;; TODO: update stats |
| jmp .drop_after_ack |
| |
| @@: |
| |
| mov edi, [edx + TCP_header.AckNumber] |
| sub edi, [ebx + TCP_SOCKET.SND_UNA] ; now we got the number of acked bytes in edi |
| |
| ;;; TODO: update stats |
| |
| DEBUGF 1,"TCP_input: acceptable ACK for %u bytes\n", edi |
| |
| ;------------------------------------------ |
| ; RTT measurements and retransmission timer (912-926) |
| |
| ; If we have a timestamp, update smoothed RTT |
| |
| test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
| jz .timestamp_not_present |
| mov eax, [esp+4] |
| sub eax, [ebx + TCP_SOCKET.ts_ecr] |
| inc eax |
| call TCP_xmit_timer |
| jmp .rtt_done_ |
| |
| ; If no timestamp but transmit timer is running and timed sequence number was acked, |
| ; update smoothed RTT. Since we now have an RTT measurement, cancel the timer backoff |
| ; (Phil Karn's retransmit algo) |
| ; Recompute the initial retransmit timer |
| |
| .timestamp_not_present: |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.t_rtseq] |
| jbe .rtt_done_ |
| mov eax, [ebx + TCP_SOCKET.t_rtt] |
| test eax, eax |
| jz .rtt_done_ |
| call TCP_xmit_timer |
| |
| .rtt_done_: |
| |
| ; If all outstanding data is acked, stop retransmit timer and remember to restart (more output or persist) |
| ; If there is more data to be acked, restart retransmit timer, using current (possible backed-off) value. |
| |
| mov eax, [ebx + TCP_SOCKET.SND_MAX] |
| cmp eax, [edx + TCP_header.AckNumber] |
| jne .more_data |
| mov [ebx + TCP_SOCKET.timer_retransmission], 0 |
| or [ebx + TCP_SOCKET.temp_bits], TCP_BIT_NEEDOUTPUT |
| jmp .no_restart |
| .more_data: |
| cmp [ebx + TCP_SOCKET.timer_persist], 0 |
| jne .no_restart |
| |
| mov eax, [ebx + TCP_SOCKET.t_rxtcur] |
| mov [ebx + TCP_SOCKET.timer_retransmission], eax |
| |
| .no_restart: |
| |
| |
| ;------------------------------------------- |
| ; Open congestion window in response to ACKs |
| |
| mov esi, [ebx + TCP_SOCKET.SND_CWND] |
| mov eax, [ebx + TCP_SOCKET.t_maxseg] |
| |
| cmp esi, [ebx + TCP_SOCKET.SND_SSTHRESH] |
| jbe @f |
| push edx |
| push eax |
| mul eax |
| div esi |
| pop edx |
| shr edx, 3 |
| add eax, edx |
| pop edx |
| @@: |
| |
| add esi, eax |
| |
| push ecx |
| mov cl, [ebx + TCP_SOCKET.SND_SCALE] |
| mov eax, TCP_max_win |
| shl eax, cl |
| pop ecx |
| |
| cmp esi, eax |
| cmova esi, eax |
| mov [ebx + TCP_SOCKET.SND_CWND], esi |
| |
| ;------------------------------------------ |
| ; Remove acknowledged data from send buffer |
| |
| cmp edi, [ebx + STREAM_SOCKET.snd.size] |
| jbe .finiacked |
| |
| push ecx edx ebx |
| mov ecx, [ebx + STREAM_SOCKET.snd.size] |
| lea eax, [ebx + STREAM_SOCKET.snd] |
| sub [ebx + TCP_SOCKET.SND_WND], ecx |
| call SOCKET_ring_free |
| pop ebx edx ecx |
| |
| DEBUGF 1,"TCP_input: our FIN is acked\n" |
| stc |
| |
| jmp .wakeup |
| |
| .finiacked: |
| |
| push ecx edx ebx |
| mov ecx, edi |
| lea eax, [ebx + STREAM_SOCKET.snd] |
| call SOCKET_ring_free |
| pop ebx |
| sub [ebx + TCP_SOCKET.SND_WND], ecx |
| pop edx ecx |
| |
| DEBUGF 1,"TCP_input: our FIN is not acked\n" |
| clc |
| |
| ;---------------------------------------- |
| ; Wake up process waiting on send buffer |
| |
| .wakeup: |
| |
| pushf ; Keep the flags (Carry flag) |
| mov eax, ebx |
| call SOCKET_notify |
| |
| ; Update TCPS |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| mov [ebx + TCP_SOCKET.SND_UNA], eax |
| cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
| jb @f |
| mov [ebx + TCP_SOCKET.SND_NXT], eax |
| @@: |
| |
| popf |
| |
| ; General ACK handling complete |
| ; Now do the state-specific ones |
| ; Carry flag is set when our FIN is acked |
| |
| mov eax, [ebx + TCP_SOCKET.t_state] |
| jmp dword [eax*4 + .ACK_sw_list] |
| |
| .ACK_sw_list: |
| dd .ack_processed ; TCPS_CLOSED |
| dd .ack_processed ; TCPS_LISTEN |
| dd .ack_processed ; TCPS_SYN_SENT |
| dd .ack_processed ; TCPS_SYN_RECEIVED |
| dd .ack_processed ; TCPS_ESTABLISHED |
| dd .ack_processed ; TCPS_CLOSE_WAIT |
| dd .ack_fw1 ; TCPS_FIN_WAIT_1 |
| dd .ack_c ; TCPS_CLOSING |
| dd .ack_la ; TCPS_LAST_ACK |
| dd .ack_processed ; TCPS_FIN_WAIT_2 |
| dd .ack_tw ; TCPS_TIMED_WAIT |
| |
| |
| .ack_fw1: |
| jnc .ack_processed |
| |
| test [ebx + SOCKET.state], SS_CANTRCVMORE |
| jnz @f |
| mov eax, ebx |
| call SOCKET_is_disconnected |
| mov [ebx + TCP_SOCKET.timer_timed_wait], TCP_time_max_idle |
| @@: |
| mov [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2 |
| jmp .ack_processed |
| |
| .ack_c: |
| jnc .ack_processed |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
| mov eax, ebx |
| call TCP_cancel_timers |
| mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
| mov eax, ebx |
| call SOCKET_is_disconnected |
| jmp .ack_processed |
| |
| .ack_la: |
| jnc .ack_processed |
| |
| mov eax, ebx |
| call TCP_disconnect |
| jmp .drop |
| |
| .ack_tw: |
| mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
| jmp .drop_after_ack |
| |
| .reset_dupacks: ; We got a new ACK, reset duplicate ACK counter |
| mov [ebx + TCP_SOCKET.t_dupacks], 0 |
| jmp .ack_processed |
| |
| ;------- |
| ; LISTEN |
| |
| align 4 |
| .LISTEN: |
| |
| DEBUGF 1,"TCP_input: state=listen\n" |
| |
| test [edx + TCP_header.Flags], TH_RST |
| jnz .drop |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jnz .drop_with_reset |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz .drop |
| |
| ;;; TODO: check if it's a broadcast or multicast, and drop if so |
| |
| push dword [edi] ; Ipv4 source addres |
| pop [ebx + IP_SOCKET.RemoteIP] |
| |
| push [edx + TCP_header.SourcePort] |
| pop [ebx + TCP_SOCKET.RemotePort] |
| |
| push [edx + TCP_header.SequenceNumber] |
| pop [ebx + TCP_SOCKET.IRS] |
| |
| mov eax, [TCP_sequence_num] |
| add [TCP_sequence_num], 64000 / 2 |
| mov [ebx + TCP_SOCKET.ISS], eax |
| mov [ebx + TCP_SOCKET.SND_NXT], eax |
| |
| TCP_sendseqinit ebx |
| TCP_rcvseqinit ebx |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
| mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
| mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval ;;;; macro |
| |
| lea eax, [ebx + STREAM_SOCKET.snd] |
| call SOCKET_ring_create |
| |
| lea eax, [ebx + STREAM_SOCKET.rcv] |
| call SOCKET_ring_create |
| |
| and [ebx + TCP_SOCKET.temp_bits], not TCP_BIT_DROPSOCKET |
| |
| ;;; call SOCKET_notify_owner |
| |
| jmp .trim_then_step6 |
| |
| ;------------ |
| ; Active Open |
| |
| align 4 |
| .SYN_SENT: |
| |
| DEBUGF 1,"TCP_input: state=syn_sent\n" |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz @f |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| cmp eax, [ebx + TCP_SOCKET.ISS] |
| jbe .drop_with_reset |
| |
| cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
| ja .drop_with_reset |
| @@: |
| |
| test [edx + TCP_header.Flags], TH_RST |
| jz @f |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz .drop |
| |
| mov eax, ebx |
| mov ebx, ECONNREFUSED |
| call TCP_drop |
| |
| jmp .drop |
| @@: |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jz .drop |
| |
| ; at this point, segment seems to be valid |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz .no_syn_ack |
| |
| ; now, process received SYN in response to an active open |
| |
| mov eax, [edx + TCP_header.AckNumber] |
| mov [ebx + TCP_SOCKET.SND_UNA], eax |
| cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
| jbe @f |
| mov [ebx + TCP_SOCKET.SND_NXT], eax |
| @@: |
| |
| .no_syn_ack: |
| mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; disable retransmission |
| |
| push [edx + TCP_header.SequenceNumber] |
| pop [ebx + TCP_SOCKET.IRS] |
| |
| TCP_rcvseqinit ebx |
| |
| or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
| |
| mov eax, [ebx + TCP_SOCKET.SND_UNA] |
| cmp eax, [ebx + TCP_SOCKET.ISS] |
| jbe .simultaneous_open |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz .simultaneous_open |
| |
| DEBUGF 1,"TCP_input: active open\n" |
| |
| ;;; TODO: update stats |
| |
| ; set socket state to connected |
| mov [ebx + SOCKET.state], SS_ISCONNECTED |
| mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
| |
| ; Do window scaling on this connection ? |
| mov eax, [ebx + TCP_SOCKET.t_flags] |
| and eax, TF_REQ_SCALE or TF_RCVD_SCALE |
| cmp eax, TF_REQ_SCALE or TF_RCVD_SCALE |
| jne .no_scaling |
| |
| mov ax, word [ebx + TCP_SOCKET.requested_s_scale] |
| mov word [ebx + TCP_SOCKET.SND_SCALE], ax |
| .no_scaling: |
| |
| ;;; TODO: reassemble packets queue |
| |
| mov eax, [ebx + TCP_SOCKET.t_rtt] |
| test eax, eax |
| je .trim_then_step6 |
| call TCP_xmit_timer |
| jmp .trim_then_step6 |
| |
| .simultaneous_open: |
| |
| DEBUGF 1,"TCP_input: simultaneous open\n" |
| ; We have received a syn but no ACK, so we are having a simultaneous open.. |
| mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
| |
| ;------------------------------------- |
| ; Common processing for receipt of SYN |
| |
| .trim_then_step6: |
| |
| inc [edx + TCP_header.SequenceNumber] |
| |
| ;;; TODO: Drop any received data that follows receive window (590) |
| |
| mov eax, [edx + TCP_header.SequenceNumber] |
| mov [ebx + TCP_SOCKET.RCV_UP], eax |
| dec eax |
| mov [ebx + TCP_SOCKET.SND_WL1], eax |
| |
| ;------- |
| ; step 6 |
| |
| .ack_processed: |
| |
| DEBUGF 1,"TCP_input: ACK processed\n" |
| |
| ;---------------------------------------------- |
| ; check if we need to update window information |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jz .no_window_update |
| |
| mov eax, [ebx + TCP_SOCKET.SND_WL1] |
| cmp eax, [edx + TCP_header.SequenceNumber] |
| jb .update_window |
| ja @f |
| |
| mov eax, [ebx + TCP_SOCKET.SND_WL2] |
| cmp eax, [edx + TCP_header.AckNumber] |
| jb .update_window |
| ja .no_window_update |
| @@: |
| |
| mov eax, dword [edx + TCP_header.Window] |
| cmp eax, [ebx + TCP_SOCKET.SND_WND] |
| jbe .no_window_update |
| |
| .update_window: |
| |
| ;;; TODO: update stats (Keep track of pure window updates) |
| |
| mov eax, dword [edx + TCP_header.Window] |
| cmp eax, [ebx + TCP_SOCKET.max_sndwnd] |
| jbe @f |
| mov [ebx + TCP_SOCKET.max_sndwnd], eax |
| @@: |
| mov [ebx + TCP_SOCKET.SND_WND], eax |
| |
| DEBUGF 1,"TCP_input: Updating window to %u\n", eax |
| |
| push [edx + TCP_header.SequenceNumber] |
| pop [ebx + TCP_SOCKET.SND_WL1] |
| |
| push [edx + TCP_header.AckNumber] |
| pop [ebx + TCP_SOCKET.SND_WL2] |
| |
| or [ebx + TCP_SOCKET.temp_bits], TCP_BIT_NEEDOUTPUT |
| |
| .no_window_update: |
| |
| ;----------------- |
| ; process URG flag |
| |
| test [edx + TCP_header.Flags], TH_URG |
| jz .not_urgent |
| |
| cmp [edx + TCP_header.UrgentPointer], 0 |
| jz .not_urgent |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
| je .not_urgent |
| |
| ; Ignore bogus urgent offsets |
| |
| movzx eax, [edx + TCP_header.UrgentPointer] |
| add eax, [ebx + STREAM_SOCKET.rcv.size] |
| cmp eax, SOCKET_MAXDATA |
| jbe .not_urgent |
| |
| mov [edx + TCP_header.UrgentPointer], 0 |
| and [edx + TCP_header.Flags], not (TH_URG) |
| jmp .do_data |
| |
| .not_urgent: |
| |
| ; processing of received urgent pointer |
| |
| ;;; TODO (1051-1093) |
| |
| |
| ;--------------------------------------- |
| ; process the data in the segment (1094) |
| |
| .do_data: |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
| jae .final_processing |
| |
| test [edx + TCP_header.Flags], TH_FIN |
| jnz @f |
| |
| test ecx, ecx |
| jnz .final_processing |
| @@: |
| |
| |
| ; The segment is in order? |
| mov eax, [edx + TCP_header.SequenceNumber] |
| cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
| jne .out_of_order |
| |
| ; The reassembly queue is empty? |
| cmp [ebx + TCP_SOCKET.seg_next], 0 |
| jne .out_of_order |
| |
| ; The connection is established? |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
| jne .out_of_order |
| |
| ; Ok, lets do this.. Set delayed ACK flag and copy data into socket buffer |
| or [ebx + TCP_SOCKET.t_flags], TF_DELACK |
| |
| pusha |
| movzx esi, [edx + TCP_header.DataOffset] |
| add esi, edx |
| lea eax, [ebx + STREAM_SOCKET.rcv] |
| call SOCKET_ring_write ; Add the data to the socket buffer |
| add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied |
| popa |
| |
| ; Wake up the sleeping process |
| mov eax, ebx |
| call SOCKET_notify |
| |
| jmp .data_done |
| |
| .out_of_order: |
| |
| ; Uh-oh, some data is out of order, lets call TCP reassemble for help |
| |
| call TCP_reassemble |
| |
| DEBUGF 1, "1470\n" |
| or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
| |
| .data_done: |
| |
| ;--------------- |
| ; FIN processing |
| |
| test [edx + TCP_header.Flags], TH_FIN |
| jz .final_processing |
| |
| DEBUGF 1,"TCP_input: Processing FIN\n" |
| |
| cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
| jae .not_first_fin |
| |
| DEBUGF 1,"TCP_input: First FIN for this connection\n" |
| |
| mov eax, ebx |
| call SOCKET_cant_recv_more |
| |
| mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
| inc [ebx + TCP_SOCKET.RCV_NXT] |
| |
| .not_first_fin: |
| mov eax, [ebx + TCP_SOCKET.t_state] |
| shl eax, 2 |
| jmp dword [eax + .FIN_sw_list] |
| |
| .FIN_sw_list: |
| dd .final_processing ; TCPS_CLOSED |
| dd .final_processing ; TCPS_LISTEN |
| dd .final_processing ; TCPS_SYN_SENT |
| dd .fin_syn_est ; TCPS_SYN_RECEIVED |
| dd .fin_syn_est ; TCPS_ESTABLISHED |
| dd .final_processing ; TCPS_CLOSE_WAIT |
| dd .fin_wait1 ; TCPS_FIN_WAIT_1 |
| dd .final_processing ; TCPS_CLOSING |
| dd .final_processing ; TCPS_LAST_ACK |
| dd .fin_wait2 ; TCPS_FIN_WAIT_2 |
| dd .fin_timed ; TCPS_TIMED_WAIT |
| |
| .fin_syn_est: |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT |
| jmp .final_processing |
| |
| .fin_wait1: |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSING |
| jmp .final_processing |
| |
| .fin_wait2: |
| |
| mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
| mov eax, ebx |
| call TCP_cancel_timers |
| mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
| call SOCKET_is_disconnected |
| jmp .final_processing |
| |
| .fin_timed: |
| mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
| jmp .final_processing |
| |
| |
| .drop_after_ack: |
| DEBUGF 1,"TCP_input: Drop after ACK\n" |
| |
| push edx ebx |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| pop eax edx |
| |
| test [edx + TCP_header.Flags], TH_RST |
| jnz .dumpit |
| |
| or [eax + TCP_SOCKET.t_flags], TF_ACKNOW |
| jmp .need_output |
| |
| .drop_with_reset: |
| DEBUGF 1,"TCP_input: Drop with reset\n" |
| |
| push ebx edx |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| pop edx ebx |
| |
| test [edx + TCP_header.Flags], TH_RST |
| jnz .dumpit |
| |
| ;;; if its a multicast/broadcast, also drop |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jnz .respond_ack |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jnz .respond_syn |
| jmp .dumpit |
| |
| ;----------------- |
| ; Final processing |
| |
| .final_processing: |
| DEBUGF 1,"TCP_input: Final processing\n" |
| |
| push ebx |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| pop eax |
| |
| test [eax + TCP_SOCKET.temp_bits], TCP_BIT_NEEDOUTPUT |
| jnz .need_output |
| |
| test [eax + TCP_SOCKET.t_flags], TF_ACKNOW |
| jz .dumpit |
| DEBUGF 1,"TCP_input: ACK now!\n" |
| |
| .need_output: |
| DEBUGF 1,"TCP_input: need output\n" |
| call TCP_output |
| |
| .dumpit: |
| DEBUGF 1,"TCP_input: dumping\n" |
| |
| call kernel_free |
| add esp, 4 |
| jmp .loop |
| |
| ;--------- |
| ; Respond |
| |
| .respond_ack: |
| push ebx |
| mov cl, TH_RST |
| call TCP_respond |
| pop ebx |
| jmp .destroy_new_socket |
| |
| .respond_syn: |
| push ebx |
| mov cl, TH_RST + TH_ACK |
| call TCP_respond |
| pop ebx |
| jmp .destroy_new_socket |
| |
| .respond_seg_reset: |
| test [edx + TCP_header.Flags], TH_RST |
| jnz .drop_no_socket |
| |
| ;;; TODO: if its a multicast/broadcast, also drop |
| |
| test [edx + TCP_header.Flags], TH_ACK |
| jnz .respond_seg_ack |
| |
| test [edx + TCP_header.Flags], TH_SYN |
| jnz .respond_seg_syn |
| |
| jmp .drop_no_socket |
| |
| .respond_seg_ack: |
| mov cl, TH_RST |
| call TCP_respond_segment |
| jmp .drop_no_socket |
| |
| .respond_seg_syn: |
| mov cl, TH_RST + TH_ACK |
| call TCP_respond_segment |
| jmp .drop_no_socket |
| |
| ;----- |
| ; Drop |
| |
| .drop: |
| DEBUGF 1,"TCP_input: Dropping segment\n" |
| |
| pusha |
| lea ecx, [ebx + SOCKET.mutex] |
| call mutex_unlock |
| popa |
| |
| .destroy_new_socket: |
| test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_DROPSOCKET |
| jz .drop_no_socket |
| |
| mov eax, ebx |
| call SOCKET_free |
| |
| .drop_no_socket: |
| DEBUGF 1,"TCP_input: Drop (no socket)\n" |
| |
| call kernel_free |
| add esp, 4 |
| jmp .loop |
| Property changes: |
|---|
| Added: svn:eol-style |
|---|
| +native |
|---|
| \ No newline at end of property |
|---|