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Rev | Author | Line No. | Line |
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1763 | hidnplayr | 1 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
2 | ;; ;; |
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2362 | hidnplayr | 3 | ;; Copyright (C) KolibriOS team 2004-2012. All rights reserved. ;; |
1763 | hidnplayr | 4 | ;; Distributed under terms of the GNU General Public License ;; |
5 | ;; ;; |
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3143 | hidnplayr | 6 | ;; Part of the TCP/IP network stack for KolibriOS ;; |
1763 | hidnplayr | 7 | ;; ;; |
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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1733 | hidnplayr | 16 | |
1763 | hidnplayr | 17 | $Revision: 3144 $ |
1733 | hidnplayr | 18 | |
2955 | hidnplayr | 19 | align 4 |
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 | |||
2390 | hidnplayr | 24 | macro TCP_checksum IP1, IP2 { |
1733 | hidnplayr | 25 | |
26 | ;------------- |
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27 | ; Pseudoheader |
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28 | |||
2390 | hidnplayr | 29 | ; protocol type |
30 | mov edx, IP_PROTO_TCP |
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1733 | hidnplayr | 31 | |
2390 | hidnplayr | 32 | ; source address |
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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1733 | hidnplayr | 37 | |
2390 | hidnplayr | 38 | ; destination address |
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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1733 | hidnplayr | 43 | |
2390 | hidnplayr | 44 | ; size |
45 | adc dl, cl |
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46 | adc dh, ch |
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1733 | hidnplayr | 47 | |
2390 | hidnplayr | 48 | adc edx, 0 |
49 | |||
1733 | hidnplayr | 50 | ;--------------------- |
51 | ; Real header and data |
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52 | |||
2390 | hidnplayr | 53 | push esi |
54 | call checksum_1 |
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55 | call checksum_2 |
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56 | pop esi |
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1733 | hidnplayr | 57 | |
2390 | hidnplayr | 58 | } ; returns in dx only |
1733 | hidnplayr | 59 | |
60 | |||
61 | |||
62 | |||
2390 | hidnplayr | 63 | macro TCP_sendseqinit ptr { |
1733 | hidnplayr | 64 | |
2390 | hidnplayr | 65 | push edi ;;;; i dont like this static use of edi |
66 | mov edi, [ptr + TCP_SOCKET.ISS] |
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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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1733 | hidnplayr | 72 | |
73 | } |
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74 | |||
75 | |||
76 | |||
2390 | hidnplayr | 77 | macro TCP_rcvseqinit ptr { |
1733 | hidnplayr | 78 | |
2390 | hidnplayr | 79 | push edi |
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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1733 | hidnplayr | 85 | |
86 | } |
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87 | |||
88 | |||
89 | |||
2930 | hidnplayr | 90 | macro TCP_init_socket socket { |
1733 | hidnplayr | 91 | |
2612 | hidnplayr | 92 | mov [socket + TCP_SOCKET.t_maxseg], TCP_mss_default |
2953 | hidnplayr | 93 | mov [socket + TCP_SOCKET.t_flags], TF_REQ_SCALE or TF_REQ_TSTMP |
1733 | hidnplayr | 94 | |
2612 | hidnplayr | 95 | mov [socket + TCP_SOCKET.t_srtt], TCP_time_srtt_default |
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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1733 | hidnplayr | 99 | |
2612 | hidnplayr | 100 | mov [socket + TCP_SOCKET.SND_CWND], TCP_max_win shl TCP_max_winshift |
101 | mov [socket + TCP_SOCKET.SND_SSTHRESH], TCP_max_win shl TCP_max_winshift |
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1733 | hidnplayr | 102 | |
103 | |||
2612 | hidnplayr | 104 | } |
1733 | hidnplayr | 105 | |
106 | |||
107 | ;--------------------------- |
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108 | ; |
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109 | ; TCP_pull_out_of_band |
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110 | ; |
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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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118 | |||
119 | align 4 |
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120 | TCP_pull_out_of_band: |
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121 | |||
2390 | hidnplayr | 122 | DEBUGF 1,"TCP_pull_out_of_band\n" |
1733 | hidnplayr | 123 | |
2390 | hidnplayr | 124 | ;;;; 1282-1305 |
1733 | hidnplayr | 125 | |
2390 | hidnplayr | 126 | ret |
1733 | hidnplayr | 127 | |
128 | |||
129 | |||
130 | |||
131 | |||
132 | |||
133 | |||
134 | |||
135 | ;------------------------- |
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136 | ; |
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137 | ; TCP_drop |
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138 | ; |
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139 | ; IN: eax = socket ptr |
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140 | ; ebx = error number |
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141 | ; |
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142 | ; OUT: eax = socket ptr |
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143 | ; |
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144 | ;------------------------- |
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145 | align 4 |
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146 | TCP_drop: |
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147 | |||
2891 | hidnplayr | 148 | DEBUGF 1,"TCP_drop: %x\n", eax |
1733 | hidnplayr | 149 | |
2390 | hidnplayr | 150 | cmp [eax + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
151 | jb .no_syn_received |
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1733 | hidnplayr | 152 | |
2390 | hidnplayr | 153 | mov [eax + TCP_SOCKET.t_state], TCPS_CLOSED |
1733 | hidnplayr | 154 | |
2390 | hidnplayr | 155 | call TCP_output |
1733 | hidnplayr | 156 | |
157 | ;;; TODO: update stats |
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158 | |||
2390 | hidnplayr | 159 | jmp TCP_close |
1733 | hidnplayr | 160 | |
161 | .no_syn_received: |
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162 | |||
163 | ;;; TODO: update stats |
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164 | |||
165 | ;;; TODO: check if error code is "Connection timed out' and handle accordingly |
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166 | |||
2390 | hidnplayr | 167 | mov [eax + SOCKET.errorcode], ebx |
1733 | hidnplayr | 168 | |
169 | |||
170 | |||
171 | |||
172 | |||
173 | |||
174 | |||
175 | |||
176 | ;------------------------- |
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177 | ; |
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178 | ; TCP_close |
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179 | ; |
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180 | ; IN: eax = socket ptr |
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181 | ; OUT: eax = socket ptr |
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182 | ; |
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183 | ;------------------------- |
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184 | align 4 |
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185 | TCP_close: |
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186 | |||
2869 | hidnplayr | 187 | DEBUGF 1,"TCP_close: %x\n", eax |
1733 | hidnplayr | 188 | |
189 | ;;; TODO: update RTT and mean deviation |
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190 | ;;; TODO: update slow start threshold |
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191 | |||
2390 | hidnplayr | 192 | call SOCKET_is_disconnected |
1733 | hidnplayr | 193 | |
2390 | hidnplayr | 194 | ret |
1733 | hidnplayr | 195 | |
196 | |||
197 | |||
2869 | hidnplayr | 198 | ;------------------------- |
199 | ; |
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200 | ; TCP_disconnect |
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201 | ; |
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202 | ; IN: eax = socket ptr |
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203 | ; OUT: eax = socket ptr |
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204 | ; |
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205 | ;------------------------- |
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206 | align 4 |
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207 | TCP_disconnect: |
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1733 | hidnplayr | 208 | |
2891 | hidnplayr | 209 | DEBUGF 1,"TCP_disconnect: %x\n", eax |
1733 | hidnplayr | 210 | |
2869 | hidnplayr | 211 | cmp [eax + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
212 | jb TCP_close |
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1733 | hidnplayr | 213 | |
214 | |||
2869 | hidnplayr | 215 | ; TODO: implement LINGER ? |
1733 | hidnplayr | 216 | |
2869 | hidnplayr | 217 | call SOCKET_is_disconnecting |
218 | call TCP_usrclosed |
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219 | call TCP_output |
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1733 | hidnplayr | 220 | |
2869 | hidnplayr | 221 | ret |
1733 | hidnplayr | 222 | |
2869 | hidnplayr | 223 | |
224 | |||
1733 | hidnplayr | 225 | ;------------------------- |
226 | ; |
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2869 | hidnplayr | 227 | ; TCP_usrclose |
228 | ; |
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229 | ; IN: eax = socket ptr |
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230 | ; |
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231 | ;------------------------- |
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232 | align 4 |
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233 | TCP_usrclosed: |
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234 | |||
2891 | hidnplayr | 235 | DEBUGF 1,"TCP_usrclosed: %x\n", eax |
2890 | hidnplayr | 236 | |
2869 | hidnplayr | 237 | push ebx |
238 | mov ebx, [eax + TCP_SOCKET.t_state] |
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239 | mov ebx, dword [.switch + ebx*4] |
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240 | jmp ebx |
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241 | |||
242 | .switch: |
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243 | |||
244 | dd .close ; TCPS_CLOSED |
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245 | dd .close ; TCPS_LISTEN |
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246 | dd .close ; TCPS_SYN_SENT |
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247 | dd .wait1 ; TCPS_SYN_RECEIVED |
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248 | dd .wait1 ; TCPS_ESTABLISHED |
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249 | dd .last_ack ; TCPS_CLOSE_WAIT |
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250 | dd .ret ; TCPS_FIN_WAIT_1 |
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251 | dd .ret ; TCPS_CLOSING |
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252 | dd .ret ; TCPS_LAST_ACK |
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253 | dd .disc ; TCPS_FIN_WAIT_2 |
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254 | dd .disc ; TCPS_TIMED_WAIT |
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255 | |||
256 | |||
257 | .close: |
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258 | pop ebx |
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259 | mov [eax + TCP_SOCKET.t_state], TCPS_CLOSED |
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260 | call TCP_close |
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261 | ret |
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262 | |||
263 | .wait1: |
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264 | pop ebx |
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265 | mov [eax + TCP_SOCKET.t_state], TCPS_FIN_WAIT_1 |
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266 | ret |
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267 | |||
268 | .last_ack: |
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269 | pop ebx |
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270 | mov [eax + TCP_SOCKET.t_state], TCPS_LAST_ACK |
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271 | ret |
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272 | |||
273 | .disc: |
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274 | call SOCKET_is_disconnected |
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275 | .ret: |
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276 | pop ebx |
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277 | ret |
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278 | |||
279 | |||
280 | ;------------------------- |
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281 | ; |
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1733 | hidnplayr | 282 | ; TCP_outflags |
283 | ; |
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284 | ; IN: eax = socket ptr |
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285 | ; |
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286 | ; OUT: edx = flags |
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287 | ; |
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288 | ;------------------------- |
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289 | align 4 |
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290 | TCP_outflags: |
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291 | |||
2390 | hidnplayr | 292 | mov edx, [eax + TCP_SOCKET.t_state] |
293 | movzx edx, byte [edx + .flaglist] |
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1733 | hidnplayr | 294 | |
2891 | hidnplayr | 295 | DEBUGF 1,"TCP_outflags: socket=%x flags=%x\n", eax, dl |
1733 | hidnplayr | 296 | |
2390 | hidnplayr | 297 | ret |
1733 | hidnplayr | 298 | |
299 | .flaglist: |
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300 | |||
2390 | hidnplayr | 301 | db TH_RST + TH_ACK ; TCPS_CLOSED |
302 | db 0 ; TCPS_LISTEN |
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303 | db TH_SYN ; TCPS_SYN_SENT |
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304 | db TH_SYN + TH_ACK ; TCPS_SYN_RECEIVED |
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305 | db TH_ACK ; TCPS_ESTABLISHED |
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306 | db TH_ACK ; TCPS_CLOSE_WAIT |
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2890 | hidnplayr | 307 | db TH_FIN + TH_ACK ; TCPS_FIN_WAIT_1 |
308 | db TH_FIN + TH_ACK ; TCPS_CLOSING |
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309 | db TH_FIN + TH_ACK ; TCPS_LAST_ACK |
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2390 | hidnplayr | 310 | db TH_ACK ; TCPS_FIN_WAIT_2 |
311 | db TH_ACK ; TCPS_TIMED_WAIT |
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1733 | hidnplayr | 312 | |
313 | |||
314 | |||
315 | |||
316 | |||
317 | |||
318 | ;--------------------------------------- |
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319 | ; |
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1830 | hidnplayr | 320 | ; The fast way to send an ACK/RST/keepalive segment |
1733 | hidnplayr | 321 | ; |
3143 | hidnplayr | 322 | ; TCP_respond |
1733 | hidnplayr | 323 | ; |
324 | ; IN: ebx = socket ptr |
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325 | ; cl = flags |
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326 | ; |
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327 | ;-------------------------------------- |
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328 | align 4 |
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3143 | hidnplayr | 329 | TCP_respond: |
1733 | hidnplayr | 330 | |
2891 | hidnplayr | 331 | DEBUGF 1,"TCP_respond_socket: socket=%x flags=%x\n", ebx, cl |
1733 | hidnplayr | 332 | |
333 | ;--------------------- |
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334 | ; Create the IP packet |
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335 | |||
2390 | hidnplayr | 336 | push cx ebx |
337 | mov eax, [ebx + IP_SOCKET.RemoteIP] |
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2877 | hidnplayr | 338 | mov edx, [ebx + IP_SOCKET.LocalIP] |
2390 | hidnplayr | 339 | mov ecx, sizeof.TCP_header |
2877 | hidnplayr | 340 | mov di, IP_PROTO_TCP shl 8 + 128 |
2390 | hidnplayr | 341 | call IPv4_output |
342 | test edi, edi |
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343 | jz .error |
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344 | pop esi cx |
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345 | push edx eax |
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1733 | hidnplayr | 346 | |
347 | ;----------------------------------------------- |
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348 | ; Fill in the TCP header by using the socket ptr |
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349 | |||
2390 | hidnplayr | 350 | mov ax, [esi + TCP_SOCKET.LocalPort] |
351 | stosw |
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352 | mov ax, [esi + TCP_SOCKET.RemotePort] |
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353 | stosw |
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354 | mov eax, [esi + TCP_SOCKET.SND_NXT] |
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355 | bswap eax |
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356 | stosd |
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357 | mov eax, [esi + TCP_SOCKET.RCV_NXT] |
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358 | bswap eax |
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359 | stosd |
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360 | mov al, 0x50 ; Dataoffset: 20 bytes (TCP_header.DataOffset) |
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361 | stosb |
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362 | mov al, cl |
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363 | stosb |
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1830 | hidnplayr | 364 | ; mov ax, [esi + TCP_SOCKET.RCV_WND] |
365 | ; rol ax, 8 |
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2390 | hidnplayr | 366 | mov ax, 0x00a0 ;;;;;;; FIXME |
367 | stosw ; window |
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368 | xor eax, eax |
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369 | stosd ; checksum + urgentpointer |
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1733 | hidnplayr | 370 | |
371 | ;--------------------- |
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372 | ; Fill in the checksum |
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373 | |||
374 | .checksum: |
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2390 | hidnplayr | 375 | sub edi, sizeof.TCP_header |
376 | mov ecx, sizeof.TCP_header |
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377 | xchg esi, edi |
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378 | TCP_checksum (edi + IP_SOCKET.LocalIP), (edi + IP_SOCKET.RemoteIP) |
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379 | mov [esi+TCP_header.Checksum], dx |
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1733 | hidnplayr | 380 | |
381 | ;-------------------- |
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382 | ; And send the segment |
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383 | |||
2390 | hidnplayr | 384 | call [ebx + NET_DEVICE.transmit] |
385 | ret |
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1733 | hidnplayr | 386 | |
387 | .error: |
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2891 | hidnplayr | 388 | DEBUGF 1,"TCP_respond_socket: failed\n" |
389 | add esp, 2 + 4 |
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1733 | hidnplayr | 390 | |
2390 | hidnplayr | 391 | ret |
1733 | hidnplayr | 392 | |
393 | |||
394 | |||
395 | |||
396 | |||
397 | |||
398 | |||
399 | |||
400 | ;------------------------- |
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401 | ; TCP_respond.segment: |
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402 | ; |
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2600 | hidnplayr | 403 | ; IN: edx = segment ptr (a previously received segment) |
2308 | hidnplayr | 404 | ; edi = ptr to dest and src IPv4 addresses |
1733 | hidnplayr | 405 | ; cl = flags |
406 | |||
407 | align 4 |
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408 | TCP_respond_segment: |
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409 | |||
2891 | hidnplayr | 410 | DEBUGF 1,"TCP_respond_segment: frame=%x flags=%c\n", edx, cl |
1733 | hidnplayr | 411 | |
412 | ;--------------------- |
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413 | ; Create the IP packet |
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414 | |||
2600 | hidnplayr | 415 | push cx edx |
2390 | hidnplayr | 416 | mov ebx, [edi + 4] |
417 | mov eax, [edi] |
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418 | mov ecx, sizeof.TCP_header |
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419 | mov di , IP_PROTO_TCP shl 8 + 128 |
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420 | call IPv4_output |
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421 | jz .error |
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2600 | hidnplayr | 422 | pop esi cx |
1733 | hidnplayr | 423 | |
2390 | hidnplayr | 424 | push edx eax |
1733 | hidnplayr | 425 | |
426 | ;--------------------------------------------------- |
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427 | ; Fill in the TCP header by using a received segment |
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428 | |||
2390 | hidnplayr | 429 | mov ax, [esi + TCP_header.DestinationPort] |
430 | stosw |
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431 | mov ax, [esi + TCP_header.SourcePort] |
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432 | stosw |
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433 | mov eax, [esi + TCP_header.AckNumber] |
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434 | bswap eax |
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435 | stosd |
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436 | xor eax, eax |
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437 | stosd |
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438 | mov al, 0x50 ; Dataoffset: 20 bytes (sizeof.TCP_header) |
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439 | stosb |
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440 | mov al, cl |
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441 | stosb |
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442 | mov ax, 1280 |
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443 | rol ax, 8 |
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444 | stosw ; window |
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445 | xor eax, eax |
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446 | stosd ; checksum + urgentpointer |
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1733 | hidnplayr | 447 | |
448 | ;--------------------- |
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449 | ; Fill in the checksum |
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450 | |||
451 | .checksum: |
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2390 | hidnplayr | 452 | lea esi, [edi - sizeof.TCP_header] |
453 | mov ecx, sizeof.TCP_header |
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454 | TCP_checksum (esi - sizeof.IPv4_header + IPv4_header.DestinationAddress),\ ; FIXME |
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455 | (esi - sizeof.IPv4_header + IPv4_header.SourceAddress) |
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456 | mov [esi+TCP_header.Checksum], dx |
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1733 | hidnplayr | 457 | |
458 | ;-------------------- |
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459 | ; And send the segment |
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460 | |||
2390 | hidnplayr | 461 | call [ebx + NET_DEVICE.transmit] |
462 | ret |
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1733 | hidnplayr | 463 | |
464 | .error: |
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2891 | hidnplayr | 465 | DEBUGF 1,"TCP_respond_segment: failed\n" |
2390 | hidnplayr | 466 | add esp, 2+4 |
1733 | hidnplayr | 467 | |
2390 | hidnplayr | 468 | ret |
2362 | hidnplayr | 469 | |
470 | |||
2955 | hidnplayr | 471 | macro TCPT_RANGESET timer, value, min, max { |
2362 | hidnplayr | 472 | |
2955 | hidnplayr | 473 | local .min |
474 | local .max |
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475 | local .done |
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2362 | hidnplayr | 476 | |
2955 | hidnplayr | 477 | cmp value, min |
478 | jb .min |
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479 | cmp value, max |
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480 | ja .max |
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481 | |||
482 | mov timer, value |
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483 | jmp .done |
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484 | |||
485 | .min: |
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486 | mov timer, value |
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487 | jmp .done |
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488 | |||
489 | .max: |
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490 | mov timer, value |
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491 | jmp .done |
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492 | |||
493 | .done: |
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494 | } |
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495 | |||
496 | |||
497 | align 4 |
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498 | TCP_set_persist: |
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499 | |||
2937 | hidnplayr | 500 | ; First, check if retransmit timer is not set, retransmit and persist are mutually exclusive |
501 | |||
2955 | hidnplayr | 502 | cmp [eax + TCP_SOCKET.timer_retransmission], 0 |
503 | jg @f |
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2937 | hidnplayr | 504 | |
505 | ; calculate RTO |
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506 | |||
2955 | hidnplayr | 507 | push ebx |
508 | mov ebx, [eax + TCP_SOCKET.t_srtt] |
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509 | shr ebx, 2 |
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510 | add ebx, [eax + TCP_SOCKET.t_rttvar] |
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511 | shr ebx, 1 |
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2937 | hidnplayr | 512 | |
2955 | hidnplayr | 513 | mov cl, [eax + TCP_SOCKET.t_rxtshift] |
514 | shl ebx, cl |
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2937 | hidnplayr | 515 | |
516 | ; Start/restart persistance timer. |
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517 | |||
2955 | hidnplayr | 518 | TCPT_RANGESET [eax + TCP_SOCKET.timer_persist], ebx, TCP_time_pers_min, TCP_time_pers_max |
2362 | hidnplayr | 519 | |
2955 | hidnplayr | 520 | pop ebx |
2937 | hidnplayr | 521 | |
2955 | hidnplayr | 522 | cmp [eax + TCP_SOCKET.t_rxtshift], TCP_max_rxtshift |
523 | jae @f |
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524 | inc [eax + TCP_SOCKET.t_rxtshift] |
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525 | @@: |
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2930 | hidnplayr | 526 | |
2955 | hidnplayr | 527 | ret |
2937 | hidnplayr | 528 | |
529 | |||
2955 | hidnplayr | 530 | |
2930 | hidnplayr | 531 | ; eax = rtt |
532 | ; ebx = socket ptr |
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533 | |||
534 | align 4 |
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535 | TCP_xmit_timer: |
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536 | |||
2948 | hidnplayr | 537 | DEBUGF 1,"TCP_xmit_timer: socket=%x rtt=%d0ms\n", ebx, eax |
538 | |||
2937 | hidnplayr | 539 | ;TODO: update stats |
2930 | hidnplayr | 540 | |
2937 | hidnplayr | 541 | cmp [ebx + TCP_SOCKET.t_rtt], 0 |
542 | je .no_rtt_yet |
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543 | |||
544 | ; srtt is stored as a fixed point with 3 bits after the binary point. |
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545 | ; The following magic is equivalent of the smoothing algorithm in rfc793 with an alpha of .875 |
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546 | ; (srtt = rtt/8 + srtt*7/8 in fixed point) |
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547 | ; Adjust rtt to origin 0. |
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548 | |||
549 | push ecx |
||
550 | mov ecx, [ebx + TCP_SOCKET.t_srtt] |
||
551 | shr ecx, TCP_RTT_SHIFT |
||
552 | sub eax, ecx |
||
553 | dec eax |
||
554 | pop ecx |
||
555 | |||
556 | add [ebx + TCP_SOCKET.t_srtt], eax |
||
557 | ja @f |
||
558 | mov [ebx + TCP_SOCKET.t_srtt], 1 |
||
559 | @@: |
||
560 | |||
561 | ; We accumulate a smoothed rtt variance (actually, a smoothed mean difference), |
||
562 | ; then set the retransmit timer to smoothed rtt + 4 times the smoothed variance. |
||
563 | ; rttvar is stored as fixed point with 2 bits after the binary point. |
||
564 | ; The following is equivalent to rfc793 smoothing with an alpha of .75 |
||
565 | ; (rttvar = rttvar*3/4 + delta/4) (delta = eax) |
||
566 | |||
567 | ; get abs(eax) |
||
568 | push edx |
||
569 | cdq |
||
570 | xor eax, edx |
||
571 | sub eax, edx |
||
572 | |||
573 | mov edx, [ebx + TCP_SOCKET.t_rttvar] |
||
574 | shr edx, TCP_RTTVAR_SHIFT |
||
575 | sub eax, edx |
||
576 | pop edx |
||
577 | |||
578 | add [ebx + TCP_SOCKET.t_rttvar], eax |
||
579 | ja @f |
||
580 | mov [ebx + TCP_SOCKET.t_rttvar], 1 |
||
581 | @@: |
||
582 | ret |
||
583 | |||
584 | |||
585 | .no_rtt_yet: |
||
586 | |||
587 | push ecx |
||
588 | mov ecx, eax |
||
589 | shl ecx, TCP_RTT_SHIFT |
||
590 | mov [ebx + TCP_SOCKET.t_srtt], ecx |
||
591 | |||
592 | shl eax, TCP_RTTVAR_SHIFT - 1 |
||
593 | mov [ebx + TCP_SOCKET.t_rttvar], eax |
||
594 | pop ecx |
||
595 | |||
596 | ret |
||
3144 | hidnplayr | 597 | |
598 | |||
599 | |||
600 | |||
601 | ; eax = max segment size |
||
602 | ; ebx = socket ptr |
||
603 | align 4 |
||
604 | TCP_mss: |
||
605 | |||
606 | cmp eax, 1420 ; FIXME |
||
607 | jbe @f |
||
608 | mov eax, 1420 |
||
609 | @@: |
||
610 | mov [ebx + TCP_SOCKET.t_maxseg], eax |
||
611 | |||
612 | |||
613 | ret |