mirror of
https://github.com/KolibriOS/kolibrios.git
synced 2024-12-16 03:42:35 +03:00
1400 lines
33 KiB
PHP
1400 lines
33 KiB
PHP
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;; ;;
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;; Copyright (C) KolibriOS team 2004-2009. All rights reserved. ;;
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;; Distributed under terms of the GNU General Public License ;;
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;; ;;
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;; TCP.INC ;;
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;; ;;
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;; Part of the tcp/ip network stack for KolibriOS ;;
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;; ;;
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;; Written by hidnplayr@kolibrios.org ;;
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;; ;;
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;; GNU GENERAL PUBLIC LICENSE ;;
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;; Version 2, June 1991 ;;
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;; ;;
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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$Revision$
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; TCP TCB states
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TCB_LISTEN equ 1
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TCB_SYN_SENT equ 2
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TCB_SYN_RECEIVED equ 3
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TCB_ESTABLISHED equ 4
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TCB_FIN_WAIT_1 equ 5
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TCB_FIN_WAIT_2 equ 6
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TCB_CLOSE_WAIT equ 7
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TCB_CLOSING equ 8
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TCB_LAST_ACK equ 9
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TCB_TIMED_WAIT equ 10
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TCB_CLOSED equ 11
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TH_FIN equ 0x01
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TH_SYN equ 0x02
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TH_RST equ 0x04
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TH_PUSH equ 0x08
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TH_ACK equ 0x10
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TH_URG equ 0x20
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TWOMSL equ 10 ; # of secs to wait before closing socket
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TCP_RETRIES equ 5 ; Number of times to resend a Packet
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TCP_TIMEOUT equ 10 ; resend if not replied to in x hs
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TCP_QUEUE_SIZE equ 16
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struct TCP_Packet
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.SourcePort dw ?
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.DestinationPort dw ?
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.SequenceNumber dd ?
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.AckNumber dd ?
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.DataOffset db ? ; DataOffset[0-3 bits] and Reserved[4-7]
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.Flags db ? ; Reserved[0-1 bits]|URG|ACK|PSH|RST|SYN|FIN
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.Window dw ?
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.Checksum dw ?
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.UrgentPointer dw ?
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.Options rb 3
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.Padding db ?
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.Data:
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ends
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align 4
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uglobal
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TCP_PACKETS_TX rd MAX_IP
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TCP_PACKETS_RX rd MAX_IP
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TCP_IN_QUEUE rd 3*TCP_QUEUE_SIZE+3
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TCP_OUT_QUEUE rd 3*TCP_QUEUE_SIZE+3
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endg
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;-----------------------------------------------------------------
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;
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; TCP_init
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;
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; This function resets all TCP variables
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;
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; IN: /
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; OUT: /
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;
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;-----------------------------------------------------------------
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align 4
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TCP_init:
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xor eax, eax
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mov edi, TCP_PACKETS_TX
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mov ecx, 2*MAX_IP
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rep stosd
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mov dword [TCP_IN_QUEUE], TCP_QUEUE_SIZE
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mov dword [TCP_IN_QUEUE+4], TCP_IN_QUEUE + queue.data
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mov dword [TCP_IN_QUEUE+8], TCP_IN_QUEUE + queue.data
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mov dword [TCP_OUT_QUEUE], TCP_QUEUE_SIZE
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mov dword [TCP_OUT_QUEUE+4], TCP_OUT_QUEUE + queue.data
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mov dword [TCP_OUT_QUEUE+8], TCP_OUT_QUEUE + queue.data
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ret
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;-----------------------------------------------------------------
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;
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; tcp_tcb_handler
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;
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; Handles sockets in the timewait state, closing them
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; when the TCB timer expires
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;
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;-----------------------------------------------------------------
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align 4
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tcp_tcb_handler:
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; scan through all the sockets, decrementing active timers
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mov ebx, net_sockets
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cmp [ebx + SOCKET.NextPtr], 0
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je .exit
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DEBUGF 1, "K : sockets:\n"
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.next_socket:
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mov ebx, [ebx + SOCKET.NextPtr]
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or ebx, ebx
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jz .exit
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; DEBUGF 1, "K : %x-%x: %x-%x-%x-%u\n", [ebx + SOCKET.PID]:2, [ebx + SOCKET.Number]:2, [ebx + SOCKET.LocalPort]:4, [ebx + SOCKET.RemoteIP], [ebx + SOCKET.RemotePort]:4, [ebx + SOCKET.TCBState]
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cmp [ebx + SOCKET.TCBTimer], 0
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jne .decrement_tcb
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cmp [ebx + SOCKET.wndsizeTimer], 0
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jne .decrement_wnd
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jmp .next_socket
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.decrement_tcb:
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; decrement it, delete socket if TCB timer = 0 & socket in timewait state
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dec [ebx + SOCKET.TCBTimer]
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jnz .next_socket
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cmp [ebx + SOCKET.TCBState], TCB_TIMED_WAIT
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jne .next_socket
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push [ebx + SOCKET.PrevPtr]
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stdcall net_socket_free, ebx
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pop ebx
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jmp .next_socket
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.decrement_wnd:
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; TODO - prove it works!
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dec [ebx + SOCKET.wndsizeTimer]
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jmp .next_socket
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.exit:
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ret
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;***************************************************************************
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; Function
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; tcp_tx_handler
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;
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; Description
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; Handles queued TCP data
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; This is a kernel function, called by stack_handler
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;
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;***************************************************************************
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align 4
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tcp_tx_handler:
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; decrement all resend buffers timers. If they
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; expire, queue them for sending, and restart the timer.
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; If the retries counter reach 0, delete the entry
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mov esi, resendQ
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mov ecx, 0
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.next_resendq:
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; cmp ecx, NUMRESENDENTRIES
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je .exit ; None left
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cmp dword[esi + 4], 0
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jne @f ; found one
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inc ecx
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add esi, 8
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jmp .next_resendq
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@@: ; we have one. decrement it's timer by 1
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dec word[esi + 2]
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jz @f
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inc ecx
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add esi, 8
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jmp .next_resendq ; Timer not zero, so move on
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@@:
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xor ebx, ebx
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; restart timer, and decrement retries
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; After the first resend, back of on next, by a factor of 5
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mov [esi + 2], word TCP_TIMEOUT * 5
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dec byte[esi + 1]
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jnz @f
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; retries now 0, so delete from queue
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xchg [esi + 4], ebx
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@@: ; resend Packet
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pushad
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; mov eax, EMPTY_QUEUE
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; call dequeue
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; cmp ax, NO_BUFFER
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jne .tth004z
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; TODO - try again in 10ms.
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test ebx, ebx
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jnz @f
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mov [esi + 4], ebx
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@@: ; Mark it to expire in 10ms - 1 tick
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mov byte[esi + 1], 1
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mov word[esi + 2], 1
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jmp .tth005
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.tth004z:
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; we have a buffer # in ax
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; push eax ecx
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; mov ecx, IPBUFFSIZE
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; mul ecx
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; add eax, IPbuffs
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; we have the buffer address in eax
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mov edi, eax
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pop ecx
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; Now get buffer location, and copy buffer across. argh! more copying,,
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; mov esi, resendBuffer
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; @@: add esi, IPBUFFSIZE
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loop @b
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; we have resend buffer location in esi
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; mov ecx, IPBUFFSIZE
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; copy data across
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push edi
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cld
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rep movsb
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pop edi
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; queue Packet
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; mov eax, NET1OUT_QUEUE
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; mov edx, [IP_LIST]
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; cmp edx, [edi + IP_Packet.DestinationAddress]
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; jne .not_local
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; mov eax, IPIN_QUEUE
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.not_local:
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pop ebx
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; call queue
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.tth005:
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popad
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inc ecx
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add esi, 8
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jmp .next_resendq
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.exit:
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ret
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;-----------------------------------------------------------------
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;
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; TCP_Handler:
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;
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; Called by IPv4_handler,
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; this procedure will inject the tcp data diagrams in the application sockets.
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;
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; IN: Pointer to buffer in [esp]
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; size of buffer in [esp+4]
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; pointer to device struct in ebx
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; TCP Packet size in ecx
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; pointer to TCP Packet data in edx
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; SourceAddres in esi
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; OUT: /
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;
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;-----------------------------------------------------------------
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TCP_Handler :
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DEBUGF 1,"TCP_Handler\n"
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jmp .exit ;;;;
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; Look for a socket where
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; IP Packet TCP Destination Port = local Port
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; IP Packet SA = Remote IP
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; IP Packet TCP Source Port = remote Port
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mov ebx, net_sockets
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.next_socket.1:
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mov ebx, [ebx + SOCKET.NextPtr]
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or ebx, ebx
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jz .next_socket.1.exit
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; DEBUGF 1, "K : tcp_rx - 1.dport: %x - %x\n", [edx + 20 + TCP_Packet.DestinationPort]:4, [ebx + SOCKET.LocalPort]:4
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mov ax, [edx + TCP_Packet.DestinationPort] ; get the dest. port from the TCP hdr
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cmp [ebx + SOCKET.LocalPort], ax ; get the dest. port from the TCP hdr
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jne .next_socket.1 ; different - try next socket
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; DEBUGF 1, "K : tcp_rx - 1.addr: %x - %x\n", [edx + IP_Packet.SourceAddress], [ebx + SOCKET.RemoteIP]
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mov eax, esi ;[edx + IP_Packet.SourceAddress] ; get the source IP Addr from the IP hdr
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cmp [ebx + SOCKET.RemoteIP], eax ; compare with socket's remote IP
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jne .next_socket.1 ; different - try next socket
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; DEBUGF 1, "K : tcp_rx - 1.sport: %x - %x\n", [edx + 20 + TCP_Packet.SourcePort]:4, [ebx + SOCKET.RemotePort]:4
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mov ax, [edx + TCP_Packet.SourcePort] ; get the source port from the TCP hdr
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cmp [ebx + SOCKET.RemotePort], ax ; compare with socket's remote port
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jne .next_socket.1 ; different - try next socket
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; We have a complete match - use this socket
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jmp .change_state
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.next_socket.1.exit:
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; If we got here, there was no match
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; Look for a socket where
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; IP Packet TCP Destination Port = local Port
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; IP Packet SA = Remote IP
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; socket remote Port = 0
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mov ebx, net_sockets
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.next_socket.2:
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mov ebx, [ebx + SOCKET.NextPtr]
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or ebx, ebx
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jz .next_socket.2.exit
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; DEBUGF 1, "K : tcp_rx - 2.dport: %x - %x\n", [edx + 20 + TCP_Packet.DestinationPort]:4, [ebx + SOCKET.LocalPort]:4
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mov ax, [edx + TCP_Packet.DestinationPort] ; get the dest. port from the TCP hdr
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cmp [ebx + SOCKET.LocalPort], ax ; compare with socket's local port
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jne .next_socket.2 ; different - try next socket
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; DEBUGF 1, "K : tcp_rx - 2.addr: %x - %x\n", [edx + IP_Packet.SourceAddress], [ebx + SOCKET.RemoteIP]
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; mov eax, esi ;[edx + IP_Packet.SourceAddress] ; get the source IP Addr from the IP hdr
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cmp [ebx + SOCKET.RemoteIP], esi ; compare with socket's remote IP
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jne .next_socket.2 ; different - try next socket
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; DEBUGF 1, "K : tcp_rx - 2.sport: 0000 - %x\n", [ebx + SOCKET.RemotePort]:4
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cmp [ebx + SOCKET.RemotePort], 0 ; only match a remote socket of 0
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jne .next_socket.2 ; different - try next socket
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; We have a complete match - use this socket
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jmp .change_state
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.next_socket.2.exit:
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; If we got here, there was no match
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; Look for a socket where
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; IP Packet TCP Destination Port = local Port
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; socket Remote IP = 0
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; socket remote Port = 0
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mov ebx, net_sockets
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.next_socket.3:
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mov ebx, [ebx + SOCKET.NextPtr]
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or ebx, ebx
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jz .next_socket.3.exit
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; DEBUGF 1, "K : tcp_rx - 3.dport: %x - %x\n", [edx + 20 + TCP_Packet.DestinationPort]:4, [ebx + SOCKET.LocalPort]:4
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mov ax, [edx + TCP_Packet.DestinationPort] ; get destination port from the TCP hdr
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cmp [ebx + SOCKET.LocalPort], ax ; compare with socket's local port
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jne .next_socket.3 ; different - try next socket
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; DEBUGF 1, "K : tcp_rx - 3.addr: 00000000 - %x\n", [ebx + SOCKET.RemoteIP]
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cmp [ebx + SOCKET.RemoteIP], 0 ; only match a socket remote IP of 0
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jne .next_socket.3 ; different - try next socket
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; DEBUGF 1, "K : tcp_rx - 3.sport: 0000 - %x\n", [ebx + SOCKET.RemotePort]:4
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cmp [ebx + SOCKET.RemotePort], 0 ; only match a remote socket of 0
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jne .next_socket.3 ; different - try next socket
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; We have a complete match - use this socket
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jmp .change_state
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.next_socket.3.exit:
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; If we got here, we need to reject the Packet
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DEBUGF 1, "K : tcp_rx - dumped\n"
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; DEBUGF 1, "K : --------: %x-%x-%x (flags: %x)\n", [edx + 20 + TCP_Packet.DestinationPort]:4, [edx + IP_Packet.SourceAddress], [edx + 20 + TCP_Packet.SourcePort]:4, [edx + 20 + TCP_Packet.Flags]:2
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; inc [dumped_rx_count]
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jmp .exit
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.change_state:
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; We have a valid socket/TCB, so call the TCB State Machine for that skt.
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; socket is pointed to by ebx
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; IP Packet is pointed to by edx
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; IP buffer number is on stack ( it will be popped at the end)
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stdcall tcpStateMachine, ebx
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.exit:
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call kernel_free
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add esp, 4 ; pop (balance stack)
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ret
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;-----------------------------------------------------------------
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;
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; IN: eax = dest ip
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; ebx = source ip
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; ecx = data length
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; edx = remote port shl 16 + local port
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; esi = data offset
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;
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;-----------------------------------------------------------------
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TCP_create_Packet:
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DEBUGF 1,"Create TCP Packet\n"
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;***************************************************************************
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; Function
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; buildTCPPacket
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;
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; Description
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; builds an IP Packet with TCP data fully populated for transmission
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; You may destroy any and all registers
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; TCP control flags specified in bl
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; This TCB is in [sktAddr]
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; User data pointed to by esi
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; Data length in ecx
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; Transmit buffer number in eax
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;
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;***************************************************************************
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push ecx ; Save data length
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add ecx, UDP_Packet.Data
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mov di , IP_PROTO_UDP
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; dx = fragment id
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call IPv4_create_Packet ; TODO: figure out a way to choose between IPv4 and IPv6
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cmp edi, -1
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je .exit
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mov [edi + TCP_Packet.Flags], bl ; TCP flags
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; mov ebx, [sockAddr];---------------------------------------------------------- eof
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; So, ebx holds the socket ptr, edx holds the IPbuffer ptr
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; Fill in the IP header ( some data is in the socket descriptor)
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mov eax, [ebx + SOCKET.LocalIP]
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; mov [edx + IP_Packet.SourceAddress], eax
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mov eax, [ebx + SOCKET.RemoteIP]
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; mov [edx + IP_Packet.DestinationAddress], eax
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; mov [edx + IP_Packet.VersionAndIHL], 0x45
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; mov [edx + IP_Packet.TypeOfService], 0
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pop eax ; Get the TCP data length
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push eax
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add eax, 20 + 20 ; add IP header and TCP header lengths
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rol ax, 8
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; mov [edx + IP_Packet.TotalLength], ax
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; mov [edx + IP_Packet.Identification], 0
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; mov [edx + IP_Packet.FlagsAndFragmentOffset], 0x0040
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; mov [edx + IP_Packet.TimeToLive], 0x20
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; mov [edx + IP_Packet.Protocol], PROTOCOL_TCP
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; Checksum left unfilled
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; mov [edx + IP_Packet.HeaderChecksum], 0
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; Fill in the TCP header (some data is in the socket descriptor)
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mov ax, [ebx + SOCKET.LocalPort]
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mov [edx + 20 + TCP_Packet.SourcePort], ax ; Local Port
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mov ax, [ebx + SOCKET.RemotePort]
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mov [edx + 20 + TCP_Packet.DestinationPort], ax ; desitination Port
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; Checksum left unfilled
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mov [edx + 20 + TCP_Packet.Checksum], 0
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; sequence number
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mov eax, [ebx + SOCKET.SND_NXT]
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mov [edx + 20 + TCP_Packet.SequenceNumber], eax
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; ack number
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mov eax, [ebx + SOCKET.RCV_NXT]
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mov [edx + 20 + TCP_Packet.AckNumber], eax
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; window ( 0x2000 is default ).I could accept 4KB, fa0, ( skt buffer size)
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; 768 bytes seems better
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mov [edx + 20 + TCP_Packet.Window], 0x0003
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; Urgent pointer (0)
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mov [edx + 20 + TCP_Packet.UrgentPointer], 0
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; data offset ( 0x50 )
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mov [edx + 20 + TCP_Packet.DataOffset], 0x50
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pop ecx ; count of bytes to send
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mov ebx, ecx ; need the length later
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cmp ebx, 0
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jz @f
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mov edi, edx
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add edi, 40
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cld
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rep movsb ; copy the data across
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@@: ; we have edx as IPbuffer ptr.
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; Fill in the TCP checksum
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; First, fill in pseudoheader
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; mov eax, [edx + IP_Packet.SourceAddress]
|
|
; mov [pseudoHeader], eax
|
|
; mov eax, [edx + IP_Packet.DestinationAddress]
|
|
; mov [pseudoHeader + 4], eax
|
|
; mov word[pseudoHeader + 8], PROTOCOL_TCP shl 8 + 0
|
|
; add ebx, 20
|
|
; mov [pseudoHeader + 10], bh
|
|
; mov [pseudoHeader + 11], bl
|
|
;
|
|
; mov eax, pseudoHeader
|
|
; mov [checkAdd1], eax
|
|
; mov word[checkSize1], 12
|
|
; mov eax, edx
|
|
; add eax, 20
|
|
; mov [checkAdd2], eax
|
|
; mov eax, ebx
|
|
; mov [checkSize2], ax
|
|
;
|
|
; call checksum
|
|
|
|
; store it in the TCP checksum ( in the correct order! )
|
|
; mov ax, [checkResult]
|
|
; rol ax, 8
|
|
; mov [edx + 20 + TCP_Packet.Checksum], ax
|
|
|
|
; Fill in the IP header checksum
|
|
; movzx eax, byte [edx + IP_Packet.VersionAndIHL] ; Calculate Header length by using IHL field
|
|
; and eax, 0x0000000F ;
|
|
; shl eax, 2 ;
|
|
;
|
|
stdcall checksum_jb, edx, eax ; buf_ptr, buf_size
|
|
rol ax, 8
|
|
; mov [edx + IP_Packet.HeaderChecksum], ax
|
|
|
|
|
|
.exit:
|
|
|
|
call kernel_free
|
|
add esp, 4 ; pop (balance stack)
|
|
|
|
ret
|
|
;endp
|
|
|
|
|
|
; Increments the 32 bit value pointed to by esi in internet order
|
|
proc inc_inet_esi stdcall
|
|
; push eax
|
|
; mov eax, [esi]
|
|
; bswap eax
|
|
; inc eax
|
|
; bswap eax
|
|
; mov [esi], eax
|
|
; pop eax
|
|
; ret
|
|
inc byte[esi+0]
|
|
adc byte[esi+1],0
|
|
adc byte[esi+2],0
|
|
adc byte[esi+3],0
|
|
endp
|
|
|
|
|
|
; Increments the 32 bit value pointed to by esi in internet order
|
|
; by the value in ecx
|
|
proc add_inet_esi stdcall
|
|
push eax
|
|
mov eax, [esi]
|
|
bswap eax
|
|
add eax, ecx
|
|
bswap eax
|
|
mov [esi], eax
|
|
pop eax
|
|
ret
|
|
endp
|
|
|
|
|
|
iglobal
|
|
TCBStateHandler dd \
|
|
stateTCB_LISTEN, \
|
|
stateTCB_SYN_SENT, \
|
|
stateTCB_SYN_RECEIVED, \
|
|
stateTCB_ESTABLISHED, \
|
|
stateTCB_FIN_WAIT_1, \
|
|
stateTCB_FIN_WAIT_2, \
|
|
stateTCB_CLOSE_WAIT, \
|
|
stateTCB_CLOSING, \
|
|
stateTCB_LAST_ACK, \
|
|
stateTCB_TIME_WAIT, \
|
|
stateTCB_CLOSED
|
|
endg
|
|
|
|
|
|
;***************************************************************************
|
|
; Function
|
|
; tcpStateMachine
|
|
;
|
|
; Description
|
|
; TCP state machine
|
|
; This is a kernel function, called by tcp_rx
|
|
;
|
|
; IP buffer address given in edx
|
|
; Socket/TCB address in ebx
|
|
;
|
|
; The IP buffer will be released by the caller
|
|
;***************************************************************************
|
|
|
|
proc tcpStateMachine stdcall, sockAddr:DWORD
|
|
; as a Packet has been received, update the TCB timer
|
|
mov [ebx + SOCKET.TCBTimer], TWOMSL
|
|
|
|
; If the received Packet has an ACK bit set,
|
|
; remove any Packets in the resend queue that this
|
|
; received Packet acknowledges
|
|
pushad
|
|
test [edx + 20 + TCP_Packet.Flags], TH_ACK
|
|
jz .call_handler ; No ACK, so no data yet
|
|
|
|
; get skt number in eax
|
|
stdcall net_socket_addr_to_num, ebx
|
|
|
|
; The ack number is in [edx + 28], inet format
|
|
; skt in eax
|
|
|
|
mov esi, resendQ
|
|
xor ecx, ecx
|
|
|
|
.next_resendq:
|
|
; cmp ecx, NUMRESENDENTRIES
|
|
je .call_handler ; None left
|
|
cmp [esi + 4], eax
|
|
je @f ; found one
|
|
inc ecx
|
|
add esi, 8
|
|
jmp .next_resendq
|
|
|
|
@@: ; Can we delete this buffer?
|
|
|
|
; If yes, goto @@. No, goto .next_resendq
|
|
; Get Packet data address
|
|
|
|
push ecx
|
|
; Now get buffer location, and copy buffer across. argh! more copying,,
|
|
; imul edi, ecx, IPBUFFSIZE
|
|
; add edi, resendBuffer
|
|
|
|
; we have dest buffer location in edi. incoming Packet in edx.
|
|
; Get this Packets sequence number
|
|
; preserve al, ecx, esi, edx
|
|
mov ecx, [edi + 20 + TCP_Packet.SequenceNumber]
|
|
bswap ecx
|
|
movzx ebx, word[edi + 2]
|
|
xchg bl, bh
|
|
sub ebx, 40
|
|
add ecx, ebx ; ecx is now seq# of last byte +1, intel format
|
|
|
|
; get recievd ack #, in intel format
|
|
mov ebx, [edx + 20 + TCP_Packet.AckNumber]
|
|
bswap ebx
|
|
|
|
cmp ebx, ecx ; Finally. ecx = rx'ed ack. ebx = last byte in que
|
|
; DANGER! need to handle case that we have just
|
|
; passed the 2**32, and wrapped round!
|
|
pop ecx
|
|
jae @f ; if rx > old, delete old
|
|
|
|
inc ecx
|
|
add esi, 8
|
|
jmp .next_resendq
|
|
|
|
@@: mov dword[esi + 4], 0
|
|
inc ecx
|
|
add esi, 8
|
|
jmp .next_resendq
|
|
|
|
.call_handler:
|
|
popad
|
|
|
|
; Call handler for given TCB state
|
|
|
|
mov eax, [ebx + SOCKET.TCBState]
|
|
cmp eax, TCB_LISTEN
|
|
jb .exit
|
|
cmp eax, TCB_CLOSED
|
|
ja .exit
|
|
|
|
stdcall [TCBStateHandler + (eax - 1) * 4], [sockAddr]
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_LISTEN stdcall, sockAddr:DWORD
|
|
; In this case, we are expecting a SYN Packet
|
|
; For now, if the Packet is a SYN, process it, and send a response
|
|
; If not, ignore it
|
|
|
|
; Look at control flags
|
|
test [edx + 20 + TCP_Packet.Flags], TH_SYN
|
|
jz .exit
|
|
|
|
; We have a SYN. update the socket with this IP Packets details,
|
|
; And send a response
|
|
|
|
; mov eax, [edx + IP_Packet.SourceAddress]
|
|
; mov [ebx + SOCKET.RemoteIP], eax
|
|
; mov ax, [edx + 20 + TCP_Packet.SourcePort]
|
|
; mov [ebx + SOCKET.RemotePort], ax
|
|
; mov eax, [edx + 20 + TCP_Packet.SequenceNumber]
|
|
; mov [ebx + SOCKET.IRS], eax
|
|
; mov [ebx + SOCKET.RCV_NXT], eax
|
|
; lea esi, [ebx + SOCKET.RCV_NXT]
|
|
; call inc_inet_esi ; RCV.NXT
|
|
; mov eax, [ebx + SOCKET.ISS]
|
|
; mov [ebx + SOCKET.SND_NXT], eax
|
|
;
|
|
; Now construct the response, and queue for sending by IP
|
|
; mov eax, EMPTY_QUEUE
|
|
; call dequeue
|
|
; cmp ax, NO_BUFFER
|
|
; je .exit
|
|
|
|
push eax
|
|
mov bl, TH_SYN + TH_ACK
|
|
xor ecx, ecx
|
|
xor esi, esi
|
|
; stdcall build_tcp_Packet, [sockAddr]
|
|
|
|
; mov eax, NET1OUT_QUEUE
|
|
;;; mov edx, [stack_ip]
|
|
mov ecx, [sockAddr]
|
|
cmp edx, [ecx + SOCKET.RemoteIP]
|
|
jne .not_local
|
|
; mov eax, IPIN_QUEUE
|
|
|
|
.not_local:
|
|
; Send it.
|
|
pop ebx
|
|
;;; call queue
|
|
|
|
mov esi, [sockAddr]
|
|
mov [esi + SOCKET.TCBState], TCB_SYN_RECEIVED
|
|
|
|
; increment SND.NXT in socket
|
|
add esi, SOCKET.SND_NXT
|
|
call inc_inet_esi
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_SYN_SENT stdcall, sockAddr:DWORD
|
|
; We are awaiting an ACK to our SYN, with a SYM
|
|
; Look at control flags - expecting an ACK
|
|
|
|
mov al, [edx + 20 + TCP_Packet.Flags]
|
|
and al, TH_SYN + TH_ACK
|
|
cmp al, TH_SYN + TH_ACK
|
|
je .syn_ack
|
|
|
|
test al, TH_SYN
|
|
jz .exit
|
|
|
|
mov [ebx + SOCKET.TCBState], TCB_SYN_RECEIVED
|
|
push TH_SYN + TH_ACK
|
|
jmp .send
|
|
|
|
.syn_ack:
|
|
mov [ebx + SOCKET.TCBState], TCB_ESTABLISHED
|
|
push TH_ACK
|
|
|
|
.send:
|
|
; Store the recv.nxt field
|
|
mov eax, [edx + 20 + TCP_Packet.SequenceNumber]
|
|
|
|
; Update our recv.nxt field
|
|
mov [ebx + SOCKET.RCV_NXT], eax
|
|
lea esi, [ebx + SOCKET.RCV_NXT]
|
|
call inc_inet_esi
|
|
|
|
; Send an ACK
|
|
; Now construct the response, and queue for sending by IP
|
|
; mov eax, EMPTY_QUEUE
|
|
; call dequeue
|
|
; cmp ax, NO_BUFFER
|
|
pop ebx
|
|
je .exit
|
|
|
|
push eax
|
|
|
|
xor ecx, ecx
|
|
xor esi, esi
|
|
; stdcall build_tcp_Packet, [sockAddr]
|
|
|
|
; mov eax, NET1OUT_QUEUE
|
|
;;; mov edx, [stack_ip]
|
|
; mov ecx, [sockAddr]
|
|
; cmp edx, [ecx + SOCKET.RemoteIP]
|
|
; jne .not_local
|
|
; mov eax, IPIN_QUEUE
|
|
|
|
.not_local:
|
|
; Send it.
|
|
pop ebx
|
|
;;; call queue
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_SYN_RECEIVED stdcall, sockAddr:DWORD
|
|
; In this case, we are expecting an ACK Packet
|
|
; For now, if the Packet is an ACK, process it,
|
|
; If not, ignore it
|
|
|
|
test [edx + 20 + TCP_Packet.Flags], TH_RST
|
|
jz .check_ack
|
|
|
|
push [ebx + SOCKET.OrigRemotePort] [ebx + SOCKET.OrigRemoteIP]
|
|
pop [ebx + SOCKET.RemoteIP] [ebx + SOCKET.RemotePort]
|
|
|
|
mov [ebx + SOCKET.TCBState], TCB_LISTEN
|
|
jmp .exit
|
|
|
|
.check_ack:
|
|
; Look at control flags - expecting an ACK
|
|
test [edx + 20 + TCP_Packet.Flags], TH_ACK
|
|
jz .exit
|
|
|
|
mov [ebx + SOCKET.TCBState], TCB_ESTABLISHED
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_ESTABLISHED stdcall, sockAddr:DWORD
|
|
; Here we are expecting data, or a request to close
|
|
; OR both...
|
|
|
|
; Did we receive a FIN or RST?
|
|
test [edx + 20 + TCP_Packet.Flags], TH_FIN
|
|
jz .check_ack
|
|
|
|
; It was a fin or reset.
|
|
|
|
; Remove resend entries from the queue - I dont want to send any more data
|
|
pushad
|
|
|
|
; get skt #
|
|
stdcall net_socket_addr_to_num, ebx
|
|
|
|
mov esi, resendQ
|
|
mov ecx, 0
|
|
|
|
.next_resendq:
|
|
; cmp ecx, NUMRESENDENTRIES
|
|
; je .last_resendq ; None left
|
|
; cmp [esi + 4], eax
|
|
; je @f ; found one
|
|
; inc ecx
|
|
; add esi, 8
|
|
; jmp .next_resendq
|
|
|
|
@@: mov dword[esi + 4], 0
|
|
inc ecx
|
|
add esi, 8
|
|
jmp .next_resendq
|
|
|
|
.last_resendq:
|
|
popad
|
|
|
|
@@: ; Send an ACK to that fin, and enter closewait state
|
|
|
|
mov [ebx + SOCKET.TCBState], TCB_CLOSE_WAIT
|
|
lea esi, [ebx + SOCKET.RCV_NXT]
|
|
mov eax, [esi] ; save original
|
|
call inc_inet_esi
|
|
;; jmp ste_ack - NO, there may be data
|
|
|
|
.check_ack:
|
|
; Check that we received an ACK
|
|
test [edx + 20 + TCP_Packet.Flags], TH_ACK
|
|
jz .exit
|
|
|
|
; TODO - done, I think!
|
|
; First, look at the incoming window. If this is less than or equal to 1024,
|
|
; Set the socket window timer to 1. This will stop an additional Packets being queued.
|
|
; ** I may need to tweak this value, since I do not know how many Packets are already queued
|
|
mov cx, [edx + 20 + TCP_Packet.Window]
|
|
xchg cl, ch
|
|
cmp cx, 1024
|
|
ja @f
|
|
|
|
mov [ebx + SOCKET.wndsizeTimer], 1
|
|
|
|
@@: ; OK, here is the deal
|
|
; My recv.nct field holds the seq of the expected next rec byte
|
|
; if the recevied sequence number is not equal to this, do not
|
|
; increment the recv.nxt field, do not copy data - just send a
|
|
; repeat ack.
|
|
|
|
; recv.nxt is in dword [edx+24], in inet format
|
|
; recv seq is in [sktAddr]+56, in inet format
|
|
; just do a comparision
|
|
mov ecx, [ebx + SOCKET.RCV_NXT]
|
|
cmp [ebx + SOCKET.TCBState], TCB_CLOSE_WAIT
|
|
jne @f
|
|
mov ecx, eax
|
|
|
|
@@: cmp ecx, [edx + 20 + TCP_Packet.SequenceNumber]
|
|
jne .ack
|
|
|
|
|
|
; Read the data bytes, store in socket buffer
|
|
; movzx ecx, [edx + IP_Packet.TotalLength]
|
|
xchg cl, ch
|
|
sub ecx, 40 ; Discard 40 bytes of header
|
|
ja .data ; Read data, if any
|
|
|
|
; If we had received a fin, we need to ACK it.
|
|
cmp [ebx + SOCKET.TCBState], TCB_CLOSE_WAIT
|
|
je .ack
|
|
jmp .exit
|
|
|
|
.data:
|
|
push ebx
|
|
add ebx, SOCKET.lock
|
|
call wait_mutex
|
|
pop ebx
|
|
|
|
push ecx
|
|
push [ebx + SOCKET.PID] ; get socket owner PID
|
|
mov eax, [ebx + SOCKET.rxDataCount]
|
|
add eax, ecx
|
|
cmp eax, SOCKETBUFFSIZE - SOCKETHEADERSIZE
|
|
ja .overflow
|
|
|
|
mov [ebx + SOCKET.rxDataCount], eax ; increment the count of bytes in buffer
|
|
|
|
; point to the location to store the data
|
|
lea edi, [ebx + eax + SOCKETHEADERSIZE]
|
|
sub edi, ecx
|
|
|
|
add edx, 40 ; edx now points to the data
|
|
mov esi, edx
|
|
|
|
cld
|
|
rep movsb ; copy the data across
|
|
mov [ebx + SOCKET.lock], 0 ; release mutex
|
|
|
|
; flag an event to the application
|
|
pop eax
|
|
mov ecx, 1
|
|
mov esi, TASK_DATA + TASKDATA.pid
|
|
|
|
.next_pid:
|
|
cmp [esi], eax
|
|
je .found_pid
|
|
inc ecx
|
|
add esi, 0x20
|
|
cmp ecx, [TASK_COUNT]
|
|
jbe .next_pid
|
|
|
|
.found_pid:
|
|
shl ecx, 8
|
|
or [ecx + SLOT_BASE + APPDATA.event_mask], EVENT_NETWORK ; stack event
|
|
|
|
pop ecx
|
|
|
|
; Update our recv.nxt field
|
|
lea esi, [ebx + SOCKET.RCV_NXT]
|
|
call add_inet_esi
|
|
|
|
.ack:
|
|
; Send an ACK
|
|
; Now construct the response, and queue for sending by IP
|
|
; mov eax, EMPTY_QUEUE
|
|
; call dequeue
|
|
; cmp ax, NO_BUFFER
|
|
je .exit
|
|
|
|
push eax
|
|
|
|
mov bl, TH_ACK
|
|
xor ecx, ecx
|
|
xor esi, esi
|
|
; stdcall build_tcp_Packet, [sockAddr]
|
|
|
|
; mov eax, NET1OUT_QUEUE
|
|
|
|
;;; mov edx, [stack_ip]
|
|
; mov ecx, [sockAddr]
|
|
; cmp edx, [ecx + SOCKET.RemoteIP]
|
|
; jne .not_local
|
|
; mov eax, IPIN_QUEUE
|
|
|
|
.not_local:
|
|
; Send it.
|
|
pop ebx
|
|
;;; call queue
|
|
|
|
.exit:
|
|
ret
|
|
.overflow:
|
|
; no place in buffer
|
|
; so simply restore stack and exit
|
|
pop eax ecx
|
|
mov [ebx + SOCKET.lock], 0
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_FIN_WAIT_1 stdcall, sockAddr:DWORD
|
|
; We can either receive an ACK of a fin, or a fin
|
|
mov al, [edx + 20 + TCP_Packet.Flags]
|
|
and al, TH_FIN + TH_ACK
|
|
|
|
cmp al, TH_ACK
|
|
jne @f
|
|
|
|
; It was an ACK
|
|
mov [ebx + SOCKET.TCBState], TCB_FIN_WAIT_2
|
|
jmp .exit
|
|
|
|
@@: mov [ebx + SOCKET.TCBState], TCB_CLOSING
|
|
cmp al, TH_FIN
|
|
je @f
|
|
mov [ebx + SOCKET.TCBState], TCB_TIMED_WAIT
|
|
|
|
@@: lea esi, [ebx + SOCKET.RCV_NXT]
|
|
call inc_inet_esi
|
|
|
|
; Send an ACK
|
|
; mov eax, EMPTY_QUEUE
|
|
; call dequeue
|
|
; cmp ax, NO_BUFFER
|
|
je .exit
|
|
|
|
push eax
|
|
|
|
mov bl, TH_ACK
|
|
xor ecx, ecx
|
|
xor esi, esi
|
|
; stdcall build_tcp_Packet, [sockAddr]
|
|
|
|
; mov eax, NET1OUT_QUEUE
|
|
;;; mov edx, [stack_ip]
|
|
; mov ecx, [sockAddr]
|
|
; cmp edx, [ecx + SOCKET.RemoteIP]
|
|
; jne .not_local
|
|
; mov eax, IPIN_QUEUE
|
|
|
|
.not_local:
|
|
; Send it.
|
|
pop ebx
|
|
;;; call queue
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_FIN_WAIT_2 stdcall, sockAddr:DWORD
|
|
test [edx + 20 + TCP_Packet.Flags], TH_FIN
|
|
jz .exit
|
|
|
|
; Change state, as we have a fin
|
|
mov [ebx + SOCKET.TCBState], TCB_TIMED_WAIT
|
|
|
|
lea esi, [ebx + SOCKET.RCV_NXT]
|
|
call inc_inet_esi
|
|
|
|
; Send an ACK
|
|
; mov eax, EMPTY_QUEUE
|
|
; call dequeue
|
|
;; cmp ax, NO_BUFFER
|
|
; je .exit
|
|
|
|
push eax
|
|
|
|
mov bl, TH_ACK
|
|
xor ecx, ecx
|
|
xor esi, esi
|
|
; stdcall build_tcp_Packet, [sockAddr]
|
|
|
|
; mov eax, NET1OUT_QUEUE
|
|
;;; mov edx, [stack_ip]
|
|
mov ecx, [sockAddr]
|
|
cmp edx, [ecx + SOCKET.RemoteIP]
|
|
jne .not_local
|
|
; mov eax, IPIN_QUEUE
|
|
|
|
.not_local:
|
|
; Send it.
|
|
pop ebx
|
|
;;; call queue
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_CLOSE_WAIT stdcall, sockAddr:DWORD
|
|
; Intentionally left empty
|
|
; socket_close_tcp handles this
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_CLOSING stdcall, sockAddr:DWORD
|
|
; We can either receive an ACK of a fin, or a fin
|
|
test [edx + 20 + TCP_Packet.Flags], TH_ACK
|
|
jz .exit
|
|
|
|
mov [ebx + SOCKET.TCBState], TCB_TIMED_WAIT
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_LAST_ACK stdcall, sockAddr:DWORD
|
|
; Look at control flags - expecting an ACK
|
|
test [edx + 20 + TCP_Packet.Flags], TH_ACK
|
|
jz .exit
|
|
|
|
; delete the socket
|
|
stdcall net_socket_free, ebx
|
|
|
|
.exit:
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_TIME_WAIT stdcall, sockAddr:DWORD
|
|
ret
|
|
endp
|
|
|
|
|
|
proc stateTCB_CLOSED stdcall, sockAddr:DWORD
|
|
ret
|
|
endp
|
|
|
|
|
|
|
|
;; [53.7] Send data through STREAM socket
|
|
;
|
|
; @param EBX is socket number
|
|
; @param ECX is application data size (number of bytes to send)
|
|
; @param EDX is pointer to application data buffer
|
|
; @return 0 (sent successfully) or -1 (error) in EAX
|
|
;;
|
|
;proc socket_write_tcp stdcall
|
|
;local sockAddr dd ?
|
|
|
|
; DEBUGF 1, "socket_write_tcp(0x%x)\n", ebx
|
|
stdcall net_socket_num_to_addr, ebx
|
|
or eax, eax
|
|
jz .error
|
|
|
|
mov ebx, eax
|
|
; mov [sockAddr], ebx
|
|
|
|
; If the sockets window timer is nonzero, do not queue Packet
|
|
cmp [ebx + SOCKET.wndsizeTimer], 0
|
|
jne .error
|
|
|
|
; mov eax, EMPTY_QUEUE
|
|
; call dequeue
|
|
; cmp ax, NO_BUFFER
|
|
; je .error
|
|
|
|
push eax
|
|
|
|
; Get the address of the callers data
|
|
mov edi, [TASK_BASE]
|
|
add edi, TASKDATA.mem_start
|
|
add edx, [edi]
|
|
mov esi, edx
|
|
|
|
pop eax
|
|
push eax
|
|
|
|
push ecx
|
|
mov bl, TH_ACK
|
|
; stdcall build_tcp_Packet, [sockAddr]
|
|
pop ecx
|
|
|
|
; Check destination IP address.
|
|
; If it is the local host IP, route it back to IP_RX
|
|
|
|
pop ebx
|
|
push ecx
|
|
|
|
; mov eax, NET1OUT_QUEUE
|
|
;;; TODO: get device id in edx
|
|
xor edx, edx
|
|
|
|
shl edx, 2
|
|
mov edx, [IP_LIST+edx]
|
|
; mov ecx, [sockAddr]
|
|
; cmp edx, [ecx + SOCKET.RemoteIP]
|
|
; jne .not_local
|
|
; mov eax, IPIN_QUEUE
|
|
|
|
.not_local:
|
|
pop ecx
|
|
push ebx ; save ipbuffer number
|
|
|
|
;;;; call queue
|
|
|
|
; mov esi, [sockAddr]
|
|
|
|
; increament SND.NXT in socket
|
|
; Amount to increment by is in ecx
|
|
add esi, SOCKET.SND_NXT
|
|
call add_inet_esi
|
|
|
|
pop ebx
|
|
|
|
; Copy the IP buffer to a resend queue
|
|
; If there isn't one, dont worry about it for now
|
|
mov esi, resendQ
|
|
mov ecx, 0
|
|
|
|
.next_resendq:
|
|
; cmp ecx, NUMRESENDENTRIES
|
|
je .exit ; None found
|
|
cmp dword[esi + 4], 0
|
|
je @f ; found one
|
|
inc ecx
|
|
add esi, 8
|
|
jmp .next_resendq
|
|
|
|
@@: push ebx
|
|
|
|
; OK, we have a buffer descriptor ptr in esi.
|
|
; resend entry # in ecx
|
|
; Populate it
|
|
; socket #
|
|
; retries count
|
|
; retry time
|
|
; fill IP buffer associated with this descriptor
|
|
|
|
; stdcall net_socket_addr_to_num, [sockAddr]
|
|
mov [esi + 4], eax
|
|
mov byte[esi + 1], TCP_RETRIES
|
|
mov word[esi + 2], TCP_TIMEOUT
|
|
|
|
inc ecx
|
|
; Now get buffer location, and copy buffer across. argh! more copying,,
|
|
; mov edi, resendBuffer - IPBUFFSIZE
|
|
|
|
; @@: add edi, IPBUFFSIZE
|
|
loop @b
|
|
|
|
; we have dest buffer location in edi
|
|
pop eax
|
|
; convert source buffer pointer eax to the absolute address
|
|
; mov ecx, IPBUFFSIZE
|
|
; mul ecx
|
|
; add eax, IPbuffs
|
|
; mov esi, eax
|
|
|
|
; do copy
|
|
; mov ecx, IPBUFFSIZE
|
|
; cld
|
|
rep movsb
|
|
|
|
.exit:
|
|
xor eax, eax
|
|
ret
|
|
|
|
.error:
|
|
or eax, -1
|
|
ret
|
|
;endp
|
|
|
|
|
|
|
|
;***************************************************************************
|
|
; Function
|
|
; checksum
|
|
;
|
|
; Description
|
|
; checkAdd1,checkAdd2, checkSize1, checkSize2, checkResult
|
|
; Dont break anything; Most registers are used by the caller
|
|
; This code is derived from the 'C' source, cksum.c, in the book
|
|
; Internetworking with TCP/IP Volume II by D.E. Comer
|
|
;
|
|
;***************************************************************************
|
|
|
|
|
|
checksum:
|
|
pusha
|
|
; mov eax, [checkAdd1]
|
|
xor edx, edx ; edx is the accumulative checksum
|
|
xor ebx, ebx
|
|
; mov cx, [checkSize1]
|
|
shr cx, 1
|
|
jz cs1_1
|
|
|
|
cs1:
|
|
mov bh, [eax]
|
|
mov bl, [eax + 1]
|
|
|
|
add eax, 2
|
|
add edx, ebx
|
|
|
|
loopw cs1
|
|
|
|
cs1_1:
|
|
; and word [checkSize1], 0x01
|
|
jz cs_test2
|
|
|
|
mov bh, [eax]
|
|
xor bl, bl
|
|
|
|
add edx, ebx
|
|
|
|
cs_test2:
|
|
; mov cx, [checkSize2]
|
|
cmp cx, 0
|
|
jz cs_exit ; Finished if no 2nd buffer
|
|
|
|
; mov eax, [checkAdd2]
|
|
|
|
shr cx, 1
|
|
jz cs2_1
|
|
|
|
cs2:
|
|
mov bh, [eax]
|
|
mov bl, [eax + 1]
|
|
|
|
add eax, 2
|
|
add edx, ebx
|
|
|
|
loopw cs2
|
|
|
|
cs2_1:
|
|
; and word [checkSize2], 0x01
|
|
jz cs_exit
|
|
|
|
mov bh, [eax]
|
|
xor bl, bl
|
|
|
|
add edx, ebx
|
|
|
|
cs_exit:
|
|
mov ebx, edx
|
|
|
|
shr ebx, 16
|
|
and edx, 0xffff
|
|
add edx, ebx
|
|
mov eax, edx
|
|
shr eax, 16
|
|
add edx, eax
|
|
not dx
|
|
|
|
; mov [checkResult], dx
|
|
popa
|
|
ret
|
|
|