;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;; ;; 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: 3514 $ align 4 iglobal TCP_backoff db 0,1,2,3,4,5,6,6,6,6,6,6,6 endg macro TCP_checksum IP1, IP2 { ;------------- ; Pseudoheader ; protocol type mov edx, IP_PROTO_TCP ; source address add dl, byte [IP1+1] adc dh, byte [IP1+0] adc dl, byte [IP1+3] adc dh, byte [IP1+2] ; destination address adc dl, byte [IP2+1] adc dh, byte [IP2+0] adc dl, byte [IP2+3] adc dh, byte [IP2+2] ; size adc dl, cl adc dh, ch adc edx, 0 ;--------------------- ; Real header and data push esi call checksum_1 call checksum_2 pop esi } ; returns in dx only macro TCP_sendseqinit ptr { push edi ;;;; i dont like this static use of edi mov edi, [ptr + TCP_SOCKET.ISS] mov [ptr + TCP_SOCKET.SND_UP], edi mov [ptr + TCP_SOCKET.SND_MAX], edi mov [ptr + TCP_SOCKET.SND_NXT], edi mov [ptr + TCP_SOCKET.SND_UNA], edi pop edi } macro TCP_rcvseqinit ptr { push edi mov edi, [ptr + TCP_SOCKET.IRS] inc edi mov [ptr + TCP_SOCKET.RCV_NXT], edi mov [ptr + TCP_SOCKET.RCV_ADV], edi pop edi } macro TCP_init_socket socket { mov [socket + TCP_SOCKET.t_maxseg], TCP_mss_default mov [socket + TCP_SOCKET.t_flags], TF_REQ_SCALE or TF_REQ_TSTMP mov [socket + TCP_SOCKET.t_srtt], TCP_time_srtt_default mov [socket + TCP_SOCKET.t_rttvar], TCP_time_rtt_default * 4 mov [socket + TCP_SOCKET.t_rttmin], TCP_time_re_min ;;; TODO: TCP_time_rangeset mov [socket + TCP_SOCKET.SND_CWND], TCP_max_win shl TCP_max_winshift mov [socket + TCP_SOCKET.SND_SSTHRESH], TCP_max_win shl TCP_max_winshift } ;--------------------------- ; ; TCP_pull_out_of_band ; ; IN: eax = ; ebx = socket ptr ; edx = tcp packet ptr ; ; OUT: / ; ;--------------------------- align 4 TCP_pull_out_of_band: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_pull_out_of_band\n" ;;;; 1282-1305 ret ;------------------------- ; ; TCP_drop ; ; IN: eax = socket ptr ; ebx = error number ; ; OUT: eax = socket ptr ; ;------------------------- align 4 TCP_drop: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_drop: %x\n", eax cmp [eax + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED jb .no_syn_received mov [eax + TCP_SOCKET.t_state], TCPS_CLOSED push eax call TCP_output pop eax ;;; TODO: update stats jmp TCP_close .no_syn_received: ;;; TODO: update stats ;;; TODO: check if error code is "Connection timed out' and handle accordingly ; mov [eax + SOCKET.errorcode], ebx ;------------------------- ; ; TCP_close ; ; IN: eax = socket ptr ; OUT: eax = socket ptr ; ;------------------------- align 4 TCP_close: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_close: %x\n", eax ;;; TODO: update RTT and mean deviation ;;; TODO: update slow start threshold call SOCKET_is_disconnected ;; call SOCKET_free ret ;------------------------- ; ; TCP_outflags ; ; IN: eax = socket ptr ; ; OUT: edx = flags ; ;------------------------- align 4 TCP_outflags: mov edx, [eax + TCP_SOCKET.t_state] movzx edx, byte [edx + .flaglist] DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_outflags: socket=%x flags=%x\n", eax, dl ret .flaglist: db TH_RST + TH_ACK ; TCPS_CLOSED db 0 ; TCPS_LISTEN db TH_SYN ; TCPS_SYN_SENT db TH_SYN + TH_ACK ; TCPS_SYN_RECEIVED db TH_ACK ; TCPS_ESTABLISHED db TH_ACK ; TCPS_CLOSE_WAIT db TH_FIN + TH_ACK ; TCPS_FIN_WAIT_1 db TH_FIN + TH_ACK ; TCPS_CLOSING db TH_FIN + TH_ACK ; TCPS_LAST_ACK db TH_ACK ; TCPS_FIN_WAIT_2 db TH_ACK ; TCPS_TIMED_WAIT ;--------------------------------------- ; ; The fast way to send an ACK/RST/keepalive segment ; ; TCP_respond ; ; IN: ebx = socket ptr ; cl = flags ; ;-------------------------------------- align 4 TCP_respond: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: socket=%x flags=%x\n", ebx, cl ;--------------------- ; Create the IP packet push cx ebx mov eax, [ebx + IP_SOCKET.RemoteIP] mov edx, [ebx + IP_SOCKET.LocalIP] mov ecx, sizeof.TCP_header mov di, IP_PROTO_TCP shl 8 + 128 call IPv4_output test edi, edi jz .error pop esi cx push edx eax ;----------------------------------------------- ; Fill in the TCP header by using the socket ptr mov ax, [esi + TCP_SOCKET.LocalPort] stosw mov ax, [esi + TCP_SOCKET.RemotePort] stosw mov eax, [esi + TCP_SOCKET.SND_NXT] bswap eax stosd mov eax, [esi + TCP_SOCKET.RCV_NXT] bswap eax stosd mov al, 0x50 ; Dataoffset: 20 bytes (TCP_header.DataOffset) stosb mov al, cl stosb ; mov ax, [esi + TCP_SOCKET.RCV_WND] ; rol ax, 8 mov ax, 0x00a0 ;;;;;;; FIXME stosw ; window xor eax, eax stosd ; checksum + urgentpointer ;--------------------- ; Fill in the checksum .checksum: sub edi, sizeof.TCP_header mov ecx, sizeof.TCP_header xchg esi, edi TCP_checksum (edi + IP_SOCKET.LocalIP), (edi + IP_SOCKET.RemoteIP) mov [esi+TCP_header.Checksum], dx ;-------------------- ; And send the segment call [ebx + NET_DEVICE.transmit] test eax, eax jnz @f call NET_ptr_to_num4 inc [TCP_segments_tx + edi] @@: ret .error: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: failed\n" add esp, 2 + 4 ret ;------------------------- ; TCP_respond_segment: ; ; IN: edx = segment ptr (a previously received segment) ; edi = ptr to dest and src IPv4 addresses ; cl = flags align 4 TCP_respond_segment: DEBUGF DEBUG_NETWORK_VERBOSE,"TCP_respond_segment: frame=%x flags=%x\n", edx, cl ;--------------------- ; Create the IP packet push cx edx mov edx, [edi + 4] mov eax, [edi] mov ecx, sizeof.TCP_header mov di, IP_PROTO_TCP shl 8 + 128 call IPv4_output jz .error pop esi cx push edx eax ;--------------------------------------------------- ; Fill in the TCP header by using a received segment mov ax, [esi + TCP_header.DestinationPort] stosw mov ax, [esi + TCP_header.SourcePort] stosw mov eax, [esi + TCP_header.AckNumber] bswap eax stosd xor eax, eax stosd mov al, 0x50 ; Dataoffset: 20 bytes (sizeof.TCP_header/4 shl 4) stosb mov al, cl stosb mov ax, 1280 rol ax, 8 stosw ; window xor eax, eax stosd ; checksum + urgentpointer ;--------------------- ; Fill in the checksum lea esi, [edi - sizeof.TCP_header] mov ecx, sizeof.TCP_header TCP_checksum (esi - sizeof.IPv4_header + IPv4_header.DestinationAddress),\ ; FIXME (esi - sizeof.IPv4_header + IPv4_header.SourceAddress) mov [esi + TCP_header.Checksum], dx ;-------------------- ; And send the segment call [ebx + NET_DEVICE.transmit] test eax, eax jnz @f call NET_ptr_to_num4 inc [TCP_segments_tx + edi] @@: ret .error: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: failed\n" add esp, 2+4 ret macro TCPT_RANGESET timer, value, min, max { local .min local .max local .done cmp value, min jb .min cmp value, max ja .max mov timer, value jmp .done .min: mov timer, value jmp .done .max: mov timer, value jmp .done .done: } align 4 TCP_set_persist: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_set_persist\n" ; First, check if retransmit timer is not set, retransmit and persist are mutually exclusive test [eax + TCP_SOCKET.timer_flags], timer_flag_retransmission jnz .exit ; calculate RTO push ebx mov ebx, [eax + TCP_SOCKET.t_srtt] shr ebx, 2 add ebx, [eax + TCP_SOCKET.t_rttvar] shr ebx, 1 mov cl, [eax + TCP_SOCKET.t_rxtshift] shl ebx, cl ; Start/restart persistance timer. TCPT_RANGESET [eax + TCP_SOCKET.timer_persist], ebx, TCP_time_pers_min, TCP_time_pers_max or [ebx + TCP_SOCKET.timer_flags], timer_flag_persist pop ebx cmp [eax + TCP_SOCKET.t_rxtshift], TCP_max_rxtshift jae @f inc [eax + TCP_SOCKET.t_rxtshift] @@: .exit: ret ; eax = rtt ; ebx = socket ptr align 4 TCP_xmit_timer: DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_xmit_timer: socket=%x rtt=%d0ms\n", ebx, eax ;TODO: update stats cmp [ebx + TCP_SOCKET.t_rtt], 0 je .no_rtt_yet ; srtt is stored as a fixed point with 3 bits after the binary point. ; The following magic is equivalent of the smoothing algorithm in rfc793 with an alpha of .875 ; (srtt = rtt/8 + srtt*7/8 in fixed point) ; Adjust rtt to origin 0. push ecx mov ecx, [ebx + TCP_SOCKET.t_srtt] shr ecx, TCP_RTT_SHIFT sub eax, ecx dec eax pop ecx add [ebx + TCP_SOCKET.t_srtt], eax ja @f mov [ebx + TCP_SOCKET.t_srtt], 1 @@: ; We accumulate a smoothed rtt variance (actually, a smoothed mean difference), ; then set the retransmit timer to smoothed rtt + 4 times the smoothed variance. ; rttvar is stored as fixed point with 2 bits after the binary point. ; The following is equivalent to rfc793 smoothing with an alpha of .75 ; (rttvar = rttvar*3/4 + delta/4) (delta = eax) ; get abs(eax) push edx cdq xor eax, edx sub eax, edx mov edx, [ebx + TCP_SOCKET.t_rttvar] shr edx, TCP_RTTVAR_SHIFT sub eax, edx pop edx add [ebx + TCP_SOCKET.t_rttvar], eax ja @f mov [ebx + TCP_SOCKET.t_rttvar], 1 @@: ret .no_rtt_yet: push ecx mov ecx, eax shl ecx, TCP_RTT_SHIFT mov [ebx + TCP_SOCKET.t_srtt], ecx shl eax, TCP_RTTVAR_SHIFT - 1 mov [ebx + TCP_SOCKET.t_rttvar], eax pop ecx ret ; eax = max segment size ; ebx = socket ptr align 4 TCP_mss: cmp eax, 1420 ; FIXME jbe @f mov eax, 1420 @@: mov [ebx + TCP_SOCKET.t_maxseg], eax ret ; ebx = socket ptr ; edx = segment ptr align 4 TCP_reassemble: ret