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Rev | Author | Line No. | Line |
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3545 | hidnplayr | 1 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
2 | ;; ;; |
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5363 | yogev_ezra | 3 | ;; Copyright (C) KolibriOS team 2004-2015. All rights reserved. ;; |
3545 | hidnplayr | 4 | ;; Distributed under terms of the GNU General Public License ;; |
5 | ;; ;; |
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6 | ;; Part of the TCP/IP network stack for KolibriOS ;; |
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7 | ;; ;; |
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8 | ;; Written by hidnplayr@kolibrios.org ;; |
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9 | ;; ;; |
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10 | ;; Based on the code of 4.4BSD ;; |
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11 | ;; ;; |
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12 | ;; GNU GENERAL PUBLIC LICENSE ;; |
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13 | ;; Version 2, June 1991 ;; |
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14 | ;; ;; |
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15 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
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16 | |||
4850 | mario79 | 17 | $Revision: 6011 $ |
3545 | hidnplayr | 18 | |
19 | align 4 |
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20 | iglobal |
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21 | TCP_backoff db 0,1,2,3,4,5,6,6,6,6,6,6,6 |
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22 | endg |
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23 | |||
6011 | hidnplayr | 24 | macro tcp_checksum IP1, IP2 { |
3545 | hidnplayr | 25 | |
26 | ;------------- |
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27 | ; Pseudoheader |
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28 | |||
29 | ; protocol type |
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30 | mov edx, IP_PROTO_TCP |
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31 | |||
32 | ; source address |
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33 | add dl, byte [IP1+1] |
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34 | adc dh, byte [IP1+0] |
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35 | adc dl, byte [IP1+3] |
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36 | adc dh, byte [IP1+2] |
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37 | |||
38 | ; destination address |
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39 | adc dl, byte [IP2+1] |
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40 | adc dh, byte [IP2+0] |
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41 | adc dl, byte [IP2+3] |
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42 | adc dh, byte [IP2+2] |
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43 | |||
44 | ; size |
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45 | adc dl, cl |
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46 | adc dh, ch |
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47 | |||
48 | adc edx, 0 |
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49 | |||
50 | ;--------------------- |
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51 | ; Real header and data |
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52 | |||
53 | push esi |
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54 | call checksum_1 |
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55 | call checksum_2 |
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56 | pop esi |
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57 | |||
58 | } ; returns in dx only |
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59 | |||
60 | |||
61 | |||
62 | |||
6011 | hidnplayr | 63 | macro tcp_sendseqinit ptr { |
3545 | hidnplayr | 64 | |
6011 | hidnplayr | 65 | push edi ;;;; FIXME: i dont like this static use of edi |
3545 | hidnplayr | 66 | mov edi, [ptr + TCP_SOCKET.ISS] |
67 | mov [ptr + TCP_SOCKET.SND_UP], edi |
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68 | mov [ptr + TCP_SOCKET.SND_MAX], edi |
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69 | mov [ptr + TCP_SOCKET.SND_NXT], edi |
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70 | mov [ptr + TCP_SOCKET.SND_UNA], edi |
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71 | pop edi |
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72 | |||
73 | } |
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74 | |||
75 | |||
76 | |||
6011 | hidnplayr | 77 | macro tcp_rcvseqinit ptr { |
3545 | hidnplayr | 78 | |
79 | push edi |
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80 | mov edi, [ptr + TCP_SOCKET.IRS] |
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81 | inc edi |
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82 | mov [ptr + TCP_SOCKET.RCV_NXT], edi |
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83 | mov [ptr + TCP_SOCKET.RCV_ADV], edi |
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84 | pop edi |
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85 | |||
86 | } |
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87 | |||
88 | |||
89 | |||
6011 | hidnplayr | 90 | macro tcp_init_socket socket { |
3545 | hidnplayr | 91 | |
92 | mov [socket + TCP_SOCKET.t_maxseg], TCP_mss_default |
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93 | mov [socket + TCP_SOCKET.t_flags], TF_REQ_SCALE or TF_REQ_TSTMP |
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94 | |||
95 | mov [socket + TCP_SOCKET.t_srtt], TCP_time_srtt_default |
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96 | mov [socket + TCP_SOCKET.t_rttvar], TCP_time_rtt_default * 4 |
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97 | mov [socket + TCP_SOCKET.t_rttmin], TCP_time_re_min |
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98 | ;;; TODO: TCP_time_rangeset |
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99 | |||
100 | mov [socket + TCP_SOCKET.SND_CWND], TCP_max_win shl TCP_max_winshift |
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101 | mov [socket + TCP_SOCKET.SND_SSTHRESH], TCP_max_win shl TCP_max_winshift |
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102 | |||
103 | |||
104 | } |
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105 | |||
106 | |||
5976 | hidnplayr | 107 | ;-----------------------------------------------------------------; |
108 | ; ; |
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6011 | hidnplayr | 109 | ; tcp_pull_out_of_band ; |
5976 | hidnplayr | 110 | ; ; |
111 | ; IN: eax = ? ; |
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112 | ; ebx = socket ptr ; |
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113 | ; edx = tcp packet ptr ; |
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114 | ; ; |
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115 | ; OUT: / ; |
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116 | ; ; |
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117 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 118 | align 4 |
6011 | hidnplayr | 119 | tcp_pull_out_of_band: |
3545 | hidnplayr | 120 | |
6011 | hidnplayr | 121 | DEBUGF DEBUG_NETWORK_VERBOSE, "tcp_pull_out_of_band\n" |
3545 | hidnplayr | 122 | |
123 | ;;;; 1282-1305 |
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124 | |||
125 | ret |
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126 | |||
127 | |||
128 | |||
5976 | hidnplayr | 129 | ;-----------------------------------------------------------------; |
130 | ; ; |
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6011 | hidnplayr | 131 | ; tcp_drop ; |
5976 | hidnplayr | 132 | ; ; |
133 | ; IN: eax = socket ptr ; |
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134 | ; ebx = error number ; |
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135 | ; ; |
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136 | ; OUT: eax = socket ptr ; |
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137 | ; ; |
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138 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 139 | align 4 |
6011 | hidnplayr | 140 | tcp_drop: ; FIXME CHECKME TODO |
3545 | hidnplayr | 141 | |
6011 | hidnplayr | 142 | DEBUGF DEBUG_NETWORK_VERBOSE, "tcp_drop: %x\n", eax |
3545 | hidnplayr | 143 | |
144 | cmp [eax + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
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145 | jb .no_syn_received |
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146 | |||
147 | mov [eax + TCP_SOCKET.t_state], TCPS_CLOSED |
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148 | |||
4365 | hidnplayr | 149 | push eax |
6011 | hidnplayr | 150 | call tcp_output |
4365 | hidnplayr | 151 | pop eax |
3545 | hidnplayr | 152 | |
153 | ;;; TODO: update stats |
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154 | |||
6011 | hidnplayr | 155 | jmp tcp_close |
3545 | hidnplayr | 156 | |
157 | .no_syn_received: |
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158 | |||
159 | ;;; TODO: update stats |
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160 | |||
161 | ;;; TODO: check if error code is "Connection timed out' and handle accordingly |
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162 | |||
3674 | hidnplayr | 163 | ; mov [eax + SOCKET.errorcode], ebx |
3545 | hidnplayr | 164 | |
165 | |||
166 | |||
167 | |||
5976 | hidnplayr | 168 | ;-----------------------------------------------------------------; |
169 | ; ; |
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6011 | hidnplayr | 170 | ; tcp_disconnect ; |
5976 | hidnplayr | 171 | ; ; |
172 | ; IN: eax = socket ptr ; |
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173 | ; ; |
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174 | ; OUT: eax = socket ptr / 0 ; |
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175 | ; ; |
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176 | ;-----------------------------------------------------------------; |
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4366 | hidnplayr | 177 | align 4 |
6011 | hidnplayr | 178 | tcp_disconnect: |
3545 | hidnplayr | 179 | |
4366 | hidnplayr | 180 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_disconnect: %x\n", eax |
3545 | hidnplayr | 181 | |
4366 | hidnplayr | 182 | cmp [eax + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
6011 | hidnplayr | 183 | jb tcp_close ; Connection not yet synchronised, just get rid of the socket |
3545 | hidnplayr | 184 | |
4366 | hidnplayr | 185 | ; TODO: implement LINGER |
3545 | hidnplayr | 186 | |
6011 | hidnplayr | 187 | call socket_is_disconnecting |
188 | call tcp_usrclosed |
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4366 | hidnplayr | 189 | |
190 | test eax, eax |
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191 | jz @f |
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192 | push eax |
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6011 | hidnplayr | 193 | call tcp_output |
4366 | hidnplayr | 194 | pop eax |
195 | @@: |
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196 | ret |
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197 | |||
198 | |||
5976 | hidnplayr | 199 | ;-----------------------------------------------------------------; |
200 | ; ; |
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6011 | hidnplayr | 201 | ; tcp_close ; |
5976 | hidnplayr | 202 | ; ; |
203 | ; IN: eax = socket ptr ; |
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204 | ; ; |
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205 | ; OUT: / ; |
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206 | ; ; |
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207 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 208 | align 4 |
6011 | hidnplayr | 209 | tcp_close: |
3545 | hidnplayr | 210 | |
3556 | hidnplayr | 211 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_close: %x\n", eax |
3545 | hidnplayr | 212 | |
213 | ;;; TODO: update RTT and mean deviation |
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214 | ;;; TODO: update slow start threshold |
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215 | |||
6011 | hidnplayr | 216 | call socket_is_disconnected |
217 | call socket_free |
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3545 | hidnplayr | 218 | |
4366 | hidnplayr | 219 | xor eax, eax |
3545 | hidnplayr | 220 | ret |
221 | |||
222 | |||
223 | |||
5976 | hidnplayr | 224 | ;-----------------------------------------------------------------; |
225 | ; ; |
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6011 | hidnplayr | 226 | ; tcp_outflags ; |
5976 | hidnplayr | 227 | ; ; |
228 | ; IN: eax = socket ptr ; |
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229 | ; ; |
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230 | ; OUT: edx = flags ; |
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231 | ; ; |
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232 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 233 | align 4 |
6011 | hidnplayr | 234 | tcp_outflags: |
3545 | hidnplayr | 235 | |
236 | mov edx, [eax + TCP_SOCKET.t_state] |
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6011 | hidnplayr | 237 | movzx edx, byte[edx + .flaglist] |
3545 | hidnplayr | 238 | |
3556 | hidnplayr | 239 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_outflags: socket=%x flags=%x\n", eax, dl |
3545 | hidnplayr | 240 | |
241 | ret |
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242 | |||
243 | .flaglist: |
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244 | |||
245 | db TH_RST + TH_ACK ; TCPS_CLOSED |
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246 | db 0 ; TCPS_LISTEN |
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247 | db TH_SYN ; TCPS_SYN_SENT |
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248 | db TH_SYN + TH_ACK ; TCPS_SYN_RECEIVED |
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249 | db TH_ACK ; TCPS_ESTABLISHED |
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250 | db TH_ACK ; TCPS_CLOSE_WAIT |
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251 | db TH_FIN + TH_ACK ; TCPS_FIN_WAIT_1 |
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252 | db TH_FIN + TH_ACK ; TCPS_CLOSING |
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253 | db TH_FIN + TH_ACK ; TCPS_LAST_ACK |
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254 | db TH_ACK ; TCPS_FIN_WAIT_2 |
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255 | db TH_ACK ; TCPS_TIMED_WAIT |
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256 | |||
257 | |||
258 | |||
259 | |||
260 | |||
261 | |||
5976 | hidnplayr | 262 | ;-----------------------------------------------------------------; |
263 | ; ; |
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264 | ; TCP_respond: Fast way to send an ACK/RST/keepalive segment. ; |
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265 | ; ; |
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266 | ; IN: ebx = socket ptr ; |
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267 | ; cl = flags ; |
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268 | ; ; |
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269 | ; OUT: / ; |
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270 | ; ; |
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271 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 272 | align 4 |
6011 | hidnplayr | 273 | tcp_respond: |
3545 | hidnplayr | 274 | |
3556 | hidnplayr | 275 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: socket=%x flags=%x\n", ebx, cl |
3545 | hidnplayr | 276 | |
277 | ;--------------------- |
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278 | ; Create the IP packet |
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279 | |||
280 | push cx ebx |
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281 | mov edx, [ebx + IP_SOCKET.LocalIP] |
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5842 | hidnplayr | 282 | mov edi, [ebx + IP_SOCKET.RemoteIP] |
283 | mov al, [ebx + IP_SOCKET.ttl] |
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284 | mov ah, IP_PROTO_TCP |
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285 | mov ecx, sizeof.TCP_header |
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5584 | hidnplayr | 286 | mov ebx, [ebx + IP_SOCKET.device] |
6011 | hidnplayr | 287 | call ipv4_output |
3545 | hidnplayr | 288 | jz .error |
289 | pop esi cx |
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5522 | hidnplayr | 290 | push eax |
3545 | hidnplayr | 291 | |
292 | ;----------------------------------------------- |
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293 | ; Fill in the TCP header by using the socket ptr |
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294 | |||
295 | mov ax, [esi + TCP_SOCKET.LocalPort] |
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296 | stosw |
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297 | mov ax, [esi + TCP_SOCKET.RemotePort] |
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298 | stosw |
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299 | mov eax, [esi + TCP_SOCKET.SND_NXT] |
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300 | bswap eax |
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301 | stosd |
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302 | mov eax, [esi + TCP_SOCKET.RCV_NXT] |
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303 | bswap eax |
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304 | stosd |
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305 | mov al, 0x50 ; Dataoffset: 20 bytes (TCP_header.DataOffset) |
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306 | stosb |
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307 | mov al, cl |
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308 | stosb |
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309 | ; mov ax, [esi + TCP_SOCKET.RCV_WND] |
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310 | ; rol ax, 8 |
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311 | mov ax, 0x00a0 ;;;;;;; FIXME |
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312 | stosw ; window |
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313 | xor eax, eax |
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314 | stosd ; checksum + urgentpointer |
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315 | |||
316 | ;--------------------- |
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317 | ; Fill in the checksum |
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318 | |||
319 | .checksum: |
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320 | sub edi, sizeof.TCP_header |
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321 | mov ecx, sizeof.TCP_header |
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322 | xchg esi, edi |
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6011 | hidnplayr | 323 | tcp_checksum (edi + IP_SOCKET.LocalIP), (edi + IP_SOCKET.RemoteIP) |
3545 | hidnplayr | 324 | mov [esi+TCP_header.Checksum], dx |
325 | |||
326 | ;-------------------- |
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327 | ; And send the segment |
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328 | |||
329 | call [ebx + NET_DEVICE.transmit] |
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3644 | hidnplayr | 330 | test eax, eax |
331 | jnz @f |
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6011 | hidnplayr | 332 | call net_ptr_to_num4 |
3644 | hidnplayr | 333 | inc [TCP_segments_tx + edi] |
334 | @@: |
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3545 | hidnplayr | 335 | ret |
336 | |||
337 | .error: |
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3556 | hidnplayr | 338 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_socket: failed\n" |
3545 | hidnplayr | 339 | add esp, 2 + 4 |
340 | |||
341 | ret |
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342 | |||
343 | |||
5976 | hidnplayr | 344 | ;-----------------------------------------------------------------; |
345 | ; ; |
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6011 | hidnplayr | 346 | ; tcp_respond_segment ; |
5976 | hidnplayr | 347 | ; ; |
348 | ; IN: ebx = device ptr ; |
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349 | ; edx = segment ptr (a previously received segment) ; |
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350 | ; edi = ptr to IPv4 header ; |
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351 | ; cl = flags ; |
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352 | ; ; |
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353 | ; OUT: / ; |
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354 | ; ; |
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355 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 356 | align 4 |
6011 | hidnplayr | 357 | tcp_respond_segment: |
3545 | hidnplayr | 358 | |
5842 | hidnplayr | 359 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: frame=%x flags=%x\n", edx, cl |
3545 | hidnplayr | 360 | |
361 | ;--------------------- |
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362 | ; Create the IP packet |
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363 | |||
364 | push cx edx |
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5842 | hidnplayr | 365 | mov edx, [edi + IPv4_header.DestinationAddress] |
366 | mov edi, [edi + IPv4_header.SourceAddress] |
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3545 | hidnplayr | 367 | mov ecx, sizeof.TCP_header |
5842 | hidnplayr | 368 | mov ax, IP_PROTO_TCP shl 8 + 128 |
6011 | hidnplayr | 369 | call ipv4_output |
3545 | hidnplayr | 370 | jz .error |
371 | pop esi cx |
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372 | |||
5522 | hidnplayr | 373 | push eax |
3545 | hidnplayr | 374 | |
375 | ;--------------------------------------------------- |
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376 | ; Fill in the TCP header by using a received segment |
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377 | |||
378 | mov ax, [esi + TCP_header.DestinationPort] |
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379 | stosw |
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380 | mov ax, [esi + TCP_header.SourcePort] |
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381 | stosw |
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382 | mov eax, [esi + TCP_header.AckNumber] |
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383 | bswap eax |
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384 | stosd |
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385 | xor eax, eax |
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386 | stosd |
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387 | mov al, 0x50 ; Dataoffset: 20 bytes (sizeof.TCP_header/4 shl 4) |
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388 | stosb |
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389 | mov al, cl |
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390 | stosb |
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391 | mov ax, 1280 |
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392 | rol ax, 8 |
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393 | stosw ; window |
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394 | xor eax, eax |
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395 | stosd ; checksum + urgentpointer |
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396 | |||
397 | ;--------------------- |
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398 | ; Fill in the checksum |
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399 | |||
400 | lea esi, [edi - sizeof.TCP_header] |
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401 | mov ecx, sizeof.TCP_header |
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6011 | hidnplayr | 402 | tcp_checksum (esi - sizeof.IPv4_header + IPv4_header.DestinationAddress),\ ; FIXME |
3545 | hidnplayr | 403 | (esi - sizeof.IPv4_header + IPv4_header.SourceAddress) |
404 | mov [esi + TCP_header.Checksum], dx |
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405 | |||
406 | ;-------------------- |
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407 | ; And send the segment |
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408 | |||
409 | call [ebx + NET_DEVICE.transmit] |
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3644 | hidnplayr | 410 | test eax, eax |
411 | jnz @f |
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6011 | hidnplayr | 412 | call net_ptr_to_num4 |
3644 | hidnplayr | 413 | inc [TCP_segments_tx + edi] |
414 | @@: |
||
3545 | hidnplayr | 415 | ret |
416 | |||
417 | .error: |
||
3556 | hidnplayr | 418 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_respond_segment: failed\n" |
3545 | hidnplayr | 419 | add esp, 2+4 |
420 | |||
421 | ret |
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422 | |||
423 | |||
6011 | hidnplayr | 424 | macro tcpt_rangeset timer, value, min, max { |
3545 | hidnplayr | 425 | |
426 | local .min |
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427 | local .max |
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428 | local .done |
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429 | |||
430 | cmp value, min |
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431 | jb .min |
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432 | cmp value, max |
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433 | ja .max |
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434 | |||
435 | mov timer, value |
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436 | jmp .done |
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437 | |||
438 | .min: |
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439 | mov timer, value |
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440 | jmp .done |
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441 | |||
442 | .max: |
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443 | mov timer, value |
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444 | jmp .done |
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445 | |||
446 | .done: |
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447 | } |
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448 | |||
5976 | hidnplayr | 449 | ;-----------------------------------------------------------------; |
450 | ; ; |
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6011 | hidnplayr | 451 | ; tcp_set_persist ; |
5976 | hidnplayr | 452 | ; ; |
453 | ;-----------------------------------------------------------------; |
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3545 | hidnplayr | 454 | align 4 |
6011 | hidnplayr | 455 | tcp_set_persist: |
3545 | hidnplayr | 456 | |
3556 | hidnplayr | 457 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_set_persist\n" |
3545 | hidnplayr | 458 | |
459 | ; First, check if retransmit timer is not set, retransmit and persist are mutually exclusive |
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460 | |||
3600 | hidnplayr | 461 | test [eax + TCP_SOCKET.timer_flags], timer_flag_retransmission |
462 | jnz .exit |
||
3545 | hidnplayr | 463 | |
464 | ; calculate RTO |
||
465 | push ebx |
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466 | mov ebx, [eax + TCP_SOCKET.t_srtt] |
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467 | shr ebx, 2 |
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468 | add ebx, [eax + TCP_SOCKET.t_rttvar] |
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469 | shr ebx, 1 |
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470 | |||
471 | mov cl, [eax + TCP_SOCKET.t_rxtshift] |
||
472 | shl ebx, cl |
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473 | |||
474 | ; Start/restart persistance timer. |
||
475 | |||
6011 | hidnplayr | 476 | tcpt_rangeset [eax + TCP_SOCKET.timer_persist], ebx, TCP_time_pers_min, TCP_time_pers_max |
3600 | hidnplayr | 477 | or [ebx + TCP_SOCKET.timer_flags], timer_flag_persist |
3545 | hidnplayr | 478 | pop ebx |
479 | |||
480 | cmp [eax + TCP_SOCKET.t_rxtshift], TCP_max_rxtshift |
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481 | jae @f |
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482 | inc [eax + TCP_SOCKET.t_rxtshift] |
||
483 | @@: |
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3600 | hidnplayr | 484 | .exit: |
3545 | hidnplayr | 485 | |
486 | ret |
||
487 | |||
488 | |||
489 | |||
5976 | hidnplayr | 490 | ;-----------------------------------------------------------------; |
491 | ; ; |
||
6011 | hidnplayr | 492 | ; tcp_xmit_timer: Calculate new smoothed RTT. ; |
5976 | hidnplayr | 493 | ; ; |
494 | ; IN: eax = rtt ; |
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495 | ; ebx = socket ptr ; |
||
496 | ; ; |
||
497 | ; OUT: / ; |
||
498 | ; ; |
||
499 | ;-----------------------------------------------------------------; |
||
3545 | hidnplayr | 500 | align 4 |
6011 | hidnplayr | 501 | tcp_xmit_timer: |
3545 | hidnplayr | 502 | |
5976 | hidnplayr | 503 | DEBUGF DEBUG_NETWORK_VERBOSE, "TCP_xmit_timer: socket=0x%x rtt=%d0ms\n", ebx, eax |
3545 | hidnplayr | 504 | |
505 | ;TODO: update stats |
||
506 | |||
507 | cmp [ebx + TCP_SOCKET.t_rtt], 0 |
||
508 | je .no_rtt_yet |
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509 | |||
510 | ; srtt is stored as a fixed point with 3 bits after the binary point. |
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511 | ; The following magic is equivalent of the smoothing algorithm in rfc793 with an alpha of .875 |
||
512 | ; (srtt = rtt/8 + srtt*7/8 in fixed point) |
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513 | ; Adjust rtt to origin 0. |
||
514 | |||
515 | push ecx |
||
516 | mov ecx, [ebx + TCP_SOCKET.t_srtt] |
||
517 | shr ecx, TCP_RTT_SHIFT |
||
518 | sub eax, ecx |
||
519 | dec eax |
||
520 | pop ecx |
||
521 | |||
522 | add [ebx + TCP_SOCKET.t_srtt], eax |
||
523 | ja @f |
||
524 | mov [ebx + TCP_SOCKET.t_srtt], 1 |
||
525 | @@: |
||
526 | |||
527 | ; We accumulate a smoothed rtt variance (actually, a smoothed mean difference), |
||
528 | ; then set the retransmit timer to smoothed rtt + 4 times the smoothed variance. |
||
529 | ; rttvar is stored as fixed point with 2 bits after the binary point. |
||
530 | ; The following is equivalent to rfc793 smoothing with an alpha of .75 |
||
531 | ; (rttvar = rttvar*3/4 + delta/4) (delta = eax) |
||
532 | |||
533 | ; get abs(eax) |
||
534 | push edx |
||
535 | cdq |
||
536 | xor eax, edx |
||
537 | sub eax, edx |
||
538 | |||
539 | mov edx, [ebx + TCP_SOCKET.t_rttvar] |
||
540 | shr edx, TCP_RTTVAR_SHIFT |
||
541 | sub eax, edx |
||
542 | pop edx |
||
543 | |||
544 | add [ebx + TCP_SOCKET.t_rttvar], eax |
||
545 | ja @f |
||
546 | mov [ebx + TCP_SOCKET.t_rttvar], 1 |
||
547 | @@: |
||
548 | ret |
||
549 | |||
550 | |||
551 | .no_rtt_yet: |
||
552 | push ecx |
||
553 | mov ecx, eax |
||
554 | shl ecx, TCP_RTT_SHIFT |
||
555 | mov [ebx + TCP_SOCKET.t_srtt], ecx |
||
556 | |||
557 | shl eax, TCP_RTTVAR_SHIFT - 1 |
||
558 | mov [ebx + TCP_SOCKET.t_rttvar], eax |
||
559 | pop ecx |
||
560 | |||
561 | ret |
||
562 | |||
563 | |||
5976 | hidnplayr | 564 | ;-----------------------------------------------------------------; |
565 | ; ; |
||
6011 | hidnplayr | 566 | ; tcp_mss: Update maximum segment size ; |
5976 | hidnplayr | 567 | ; ; |
568 | ; IN: eax = max segment size ; |
||
569 | ; ebx = socket ptr ; |
||
570 | ; ; |
||
571 | ; OUT: / ; |
||
572 | ; ; |
||
573 | ;-----------------------------------------------------------------; |
||
3545 | hidnplayr | 574 | align 4 |
6011 | hidnplayr | 575 | tcp_mss: |
3545 | hidnplayr | 576 | |
5976 | hidnplayr | 577 | cmp eax, 1420 ; FIXME |
3545 | hidnplayr | 578 | jbe @f |
579 | mov eax, 1420 |
||
580 | @@: |
||
581 | mov [ebx + TCP_SOCKET.t_maxseg], eax |
||
582 | |||
583 | |||
584 | ret |
||
585 | |||
586 | |||
587 | |||
5976 | hidnplayr | 588 | ;-----------------------------------------------------------------; |
589 | ; ; |
||
6011 | hidnplayr | 590 | ; tcp_reassemble ; |
5976 | hidnplayr | 591 | ; ; |
592 | ; IN: ebx = socket ptr ; |
||
593 | ; edx = segment ptr ; |
||
594 | ; ; |
||
595 | ; OUT: / ; |
||
596 | ; ; |
||
597 | ;-----------------------------------------------------------------; |
||
3545 | hidnplayr | 598 | align 4 |
6011 | hidnplayr | 599 | tcp_reassemble: |
3545 | hidnplayr | 600 | |
5976 | hidnplayr | 601 | ;;;;; TODO |
3545 | hidnplayr | 602 | |
603 | ret |
||
604 |