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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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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 | |||
17 | $Revision: 2930 $ |
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18 | |||
1733 | hidnplayr | 19 | ;----------------------------------------------------------------- |
20 | ; |
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21 | ; TCP_input: |
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22 | ; |
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23 | ; IN: [esp] = ptr to buffer |
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24 | ; [esp+4] = buffer size |
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25 | ; ebx = ptr to device struct |
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26 | ; ecx = segment size |
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2310 | hidnplayr | 27 | ; esi = ptr to TCP segment |
2308 | hidnplayr | 28 | ; edi = ptr to ipv4 source address, followed by ipv4 dest address |
1733 | hidnplayr | 29 | ; |
30 | ; OUT: / |
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31 | ; |
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32 | ;----------------------------------------------------------------- |
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1830 | hidnplayr | 33 | |
1733 | hidnplayr | 34 | align 4 |
35 | TCP_input: |
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36 | |||
2891 | hidnplayr | 37 | DEBUGF 1,"TCP_input: size=%u\n", ecx |
1733 | hidnplayr | 38 | |
2930 | hidnplayr | 39 | ; First, record the current time |
40 | mov eax, [timer_ticks] |
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41 | mov [esp+4], eax |
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1733 | hidnplayr | 42 | |
2930 | hidnplayr | 43 | ; then, re-calculate the checksum (if not already done by hw) |
44 | ; test [ebx + NET_DEVICE.hwacc], HWACC_TCP_IPv4_IN |
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45 | ; jnz .checksum_ok |
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46 | |||
2390 | hidnplayr | 47 | push ecx esi |
48 | pushw [esi + TCP_header.Checksum] |
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49 | mov [esi + TCP_header.Checksum], 0 |
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50 | TCP_checksum (edi), (edi+4) |
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51 | pop cx ; previous checksum |
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52 | cmp cx, dx |
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53 | pop edx ecx |
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2600 | hidnplayr | 54 | jne .drop_no_socket |
2930 | hidnplayr | 55 | .checksum_ok: |
1733 | hidnplayr | 56 | |
2930 | hidnplayr | 57 | ; Verify the data offset |
2390 | hidnplayr | 58 | and [edx + TCP_header.DataOffset], 0xf0 ; Calculate TCP segment header size (throwing away unused reserved bits in TCP header) |
59 | shr [edx + TCP_header.DataOffset], 2 |
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60 | cmp [edx + TCP_header.DataOffset], sizeof.TCP_header ; Now see if it's at least the size of a standard TCP header |
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2600 | hidnplayr | 61 | jb .drop_no_socket ; If not, drop the packet |
1733 | hidnplayr | 62 | |
2390 | hidnplayr | 63 | movzx eax, [edx + TCP_header.DataOffset] |
64 | sub ecx, eax ; substract TCP header size from total segment size |
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2600 | hidnplayr | 65 | jb .drop_no_socket ; If total segment size is less then the advertised header size, drop packet |
2891 | hidnplayr | 66 | DEBUGF 1,"TCP_input: %u bytes of data\n", ecx |
1733 | hidnplayr | 67 | |
68 | ;------------------------------------------- |
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69 | ; Convert Big-endian values to little endian |
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70 | |||
2390 | hidnplayr | 71 | ntohd [edx + TCP_header.SequenceNumber] |
72 | ntohd [edx + TCP_header.AckNumber] |
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1733 | hidnplayr | 73 | |
2390 | hidnplayr | 74 | ntohw [edx + TCP_header.Window] |
75 | ntohw [edx + TCP_header.UrgentPointer] |
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76 | ntohw [edx + TCP_header.SourcePort] |
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77 | ntohw [edx + TCP_header.DestinationPort] |
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1733 | hidnplayr | 78 | |
2930 | hidnplayr | 79 | ;------------------------ |
80 | ; Find the socket pointer |
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1733 | hidnplayr | 81 | |
82 | ; IP Packet TCP Destination Port = local Port |
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83 | ; (IP Packet SenderAddress = Remote IP) OR (Remote IP = 0) |
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2309 | hidnplayr | 84 | ; (IP Packet TCP Source Port = remote Port) OR (remote Port = 0) |
1733 | hidnplayr | 85 | |
2390 | hidnplayr | 86 | mov ebx, net_sockets |
87 | mov si, [edx + TCP_header.DestinationPort] |
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1733 | hidnplayr | 88 | |
89 | .socket_loop: |
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2390 | hidnplayr | 90 | mov ebx, [ebx + SOCKET.NextPtr] |
91 | or ebx, ebx |
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2600 | hidnplayr | 92 | jz .drop_with_reset_no_socket |
1733 | hidnplayr | 93 | |
2390 | hidnplayr | 94 | cmp [ebx + SOCKET.Domain], AF_INET4 |
95 | jne .socket_loop |
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1733 | hidnplayr | 96 | |
2390 | hidnplayr | 97 | cmp [ebx + SOCKET.Protocol], IP_PROTO_TCP |
98 | jne .socket_loop |
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1733 | hidnplayr | 99 | |
2390 | hidnplayr | 100 | cmp [ebx + TCP_SOCKET.LocalPort], si |
101 | jne .socket_loop |
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1733 | hidnplayr | 102 | |
2390 | hidnplayr | 103 | mov eax, [ebx + IP_SOCKET.RemoteIP] |
104 | cmp eax, [edi] ; Ipv4 source addres |
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105 | je @f |
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106 | test eax, eax |
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107 | jnz .socket_loop |
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1733 | hidnplayr | 108 | @@: |
109 | |||
2390 | hidnplayr | 110 | mov ax, [ebx + TCP_SOCKET.RemotePort] |
111 | cmp [edx + TCP_header.SourcePort], ax |
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112 | je .found_socket |
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113 | test ax, ax |
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114 | jnz .socket_loop |
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115 | .found_socket: ; ebx now contains the socketpointer |
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2891 | hidnplayr | 116 | DEBUGF 1,"TCP_input: socket ptr=%x state=%u flags=%x\n", ebx, [ebx + TCP_SOCKET.t_state], [edx + TCP_header.Flags]:2 |
1733 | hidnplayr | 117 | |
2930 | hidnplayr | 118 | ;------------- |
2890 | hidnplayr | 119 | ; update stats |
2930 | hidnplayr | 120 | |
2890 | hidnplayr | 121 | inc [TCP_segments_rx] ; FIXME: correct interface? |
1733 | hidnplayr | 122 | |
123 | ;---------------------------- |
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124 | ; Check if socket isnt closed |
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125 | |||
2390 | hidnplayr | 126 | cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSED |
127 | je .drop_not_locked |
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1733 | hidnplayr | 128 | |
129 | ;---------------- |
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130 | ; Lock the socket |
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131 | |||
2402 | hidnplayr | 132 | pusha |
2891 | hidnplayr | 133 | pushf |
134 | cli |
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2402 | hidnplayr | 135 | lea ecx, [ebx + SOCKET.mutex] |
136 | call mutex_lock |
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2891 | hidnplayr | 137 | popf |
2402 | hidnplayr | 138 | popa |
1830 | hidnplayr | 139 | |
2891 | hidnplayr | 140 | DEBUGF 1,"TCP_input: socket locked\n" |
1733 | hidnplayr | 141 | |
2891 | hidnplayr | 142 | ;---------------------- |
143 | ; set need_output to 0 |
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144 | |||
145 | mov [ebx + TCP_SOCKET.sendalot], 0 |
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146 | |||
1733 | hidnplayr | 147 | ;--------------------------------------- |
148 | ; unscale the window into a 32 bit value |
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149 | |||
2390 | hidnplayr | 150 | movzx eax, [edx + TCP_header.Window] |
151 | push ecx |
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152 | mov cl, [ebx + TCP_SOCKET.SND_SCALE] |
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153 | shl eax, cl |
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154 | mov dword [edx + TCP_header.Window], eax ; word after window is checksum, we dont need checksum anymore |
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155 | pop ecx |
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1733 | hidnplayr | 156 | |
2930 | hidnplayr | 157 | ;--------------------------------------- |
158 | ; Are we accepting incoming connections? |
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1733 | hidnplayr | 159 | |
2390 | hidnplayr | 160 | test [ebx + SOCKET.options], SO_ACCEPTCON |
2930 | hidnplayr | 161 | jnz .accept_connection |
1733 | hidnplayr | 162 | |
163 | ;------------------------------------- |
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164 | ; Reset idle timer and keepalive timer |
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165 | |||
2390 | hidnplayr | 166 | mov [ebx + TCP_SOCKET.t_idle], 0 |
167 | mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval |
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1733 | hidnplayr | 168 | |
169 | ;-------------------- |
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170 | ; Process TCP options |
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171 | |||
2390 | hidnplayr | 172 | movzx eax, [edx + TCP_header.DataOffset] |
173 | cmp eax, sizeof.TCP_header ; Does header contain any options? |
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174 | je .no_options |
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1733 | hidnplayr | 175 | |
2891 | hidnplayr | 176 | DEBUGF 1,"TCP_input: Segment has options\n" |
1733 | hidnplayr | 177 | |
2390 | hidnplayr | 178 | cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN ; no options when in listen state |
179 | jz .not_uni_xfer ; also no header prediction |
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1733 | hidnplayr | 180 | |
2390 | hidnplayr | 181 | add eax, edx |
182 | lea esi, [edx + sizeof.TCP_header] |
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1733 | hidnplayr | 183 | |
184 | .opt_loop: |
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2390 | hidnplayr | 185 | cmp esi, eax ; are we scanning outside of header? |
186 | jae .no_options |
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1733 | hidnplayr | 187 | |
2390 | hidnplayr | 188 | cmp byte [esi], TCP_OPT_EOL ; end of option list? |
189 | jz .no_options |
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1733 | hidnplayr | 190 | |
2390 | hidnplayr | 191 | cmp byte [esi], TCP_OPT_NOP ; nop ? |
192 | jz .opt_nop |
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1733 | hidnplayr | 193 | |
2390 | hidnplayr | 194 | cmp byte [esi], TCP_OPT_MAXSEG |
195 | je .opt_maxseg |
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1733 | hidnplayr | 196 | |
2390 | hidnplayr | 197 | cmp byte [esi], TCP_OPT_WINDOW |
198 | je .opt_window |
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1733 | hidnplayr | 199 | |
2390 | hidnplayr | 200 | cmp byte [esi], TCP_OPT_TIMESTAMP |
201 | je .opt_timestamp |
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1733 | hidnplayr | 202 | |
2390 | hidnplayr | 203 | jmp .no_options ; If we reach here, some unknown options were received, skip them all! |
1733 | hidnplayr | 204 | |
205 | .opt_nop: |
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2930 | hidnplayr | 206 | inc esi |
2390 | hidnplayr | 207 | jmp .opt_loop |
1733 | hidnplayr | 208 | |
209 | .opt_maxseg: |
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2390 | hidnplayr | 210 | cmp byte [esi+1], 4 |
211 | jne .no_options ; error occured, ignore all options! |
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1733 | hidnplayr | 212 | |
2390 | hidnplayr | 213 | test [edx + TCP_header.Flags], TH_SYN |
214 | jz @f |
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1733 | hidnplayr | 215 | |
2390 | hidnplayr | 216 | movzx eax, word[esi+2] |
217 | rol ax, 8 |
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2891 | hidnplayr | 218 | DEBUGF 1,"TCP_input: Maxseg=%u\n", ax |
1733 | hidnplayr | 219 | |
2390 | hidnplayr | 220 | mov [ebx + TCP_SOCKET.t_maxseg], eax |
1733 | hidnplayr | 221 | |
222 | @@: |
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2930 | hidnplayr | 223 | add esi, 4 |
2390 | hidnplayr | 224 | jmp .opt_loop |
1733 | hidnplayr | 225 | |
226 | |||
227 | .opt_window: |
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2390 | hidnplayr | 228 | cmp byte [esi+1], 3 |
229 | jne .no_options |
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1733 | hidnplayr | 230 | |
2390 | hidnplayr | 231 | test [edx + TCP_header.Flags], TH_SYN |
232 | jz @f |
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1733 | hidnplayr | 233 | |
2891 | hidnplayr | 234 | DEBUGF 1,"TCP_input: Got window option\n" |
1733 | hidnplayr | 235 | |
2390 | hidnplayr | 236 | ;;;;; |
1733 | hidnplayr | 237 | @@: |
2930 | hidnplayr | 238 | add esi, 3 |
2390 | hidnplayr | 239 | jmp .opt_loop |
1733 | hidnplayr | 240 | |
241 | |||
242 | .opt_timestamp: |
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2930 | hidnplayr | 243 | cmp byte [esi+1], 10 ; length must be 10 |
2390 | hidnplayr | 244 | jne .no_options |
1733 | hidnplayr | 245 | |
2891 | hidnplayr | 246 | DEBUGF 1,"TCP_input: Got timestamp option\n" |
1733 | hidnplayr | 247 | |
2930 | hidnplayr | 248 | push dword [esi + 2] ; timestamp |
249 | pop [ebx + TCP_SOCKET.ts_recent] |
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1733 | hidnplayr | 250 | |
2930 | hidnplayr | 251 | push dword [esi + 6] ; timestamp echo reply |
252 | pop [ebx + TCP_SOCKET.ts_ecr] |
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253 | |||
2390 | hidnplayr | 254 | add esi, 10 |
255 | jmp .opt_loop |
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1733 | hidnplayr | 256 | |
257 | .no_options: |
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258 | |||
259 | ;----------------------------------------------------------------------- |
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260 | ; Time to do some header prediction (Original Principle by Van Jacobson) |
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261 | |||
262 | ; There are two common cases for an uni-directional data transfer. |
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263 | ; |
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264 | ; General rule: the packets has no control flags, is in-sequence, |
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265 | ; window width didnt change and we're not retransmitting. |
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266 | ; |
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267 | ; Second rules: |
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268 | ; - If the length is 0 and the ACK moved forward, we're the sender side of the transfer. |
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269 | ; In this case we'll free the ACK'ed data and notify higher levels that we have free space in buffer |
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270 | ; |
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271 | ; - If the length is not 0 and the ACK didn't move, we're the receiver side of the transfer. |
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272 | ; If the packets are in order (data queue is empty), add the data to the socket buffer and request a delayed ACK |
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273 | |||
2390 | hidnplayr | 274 | cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
275 | jnz .not_uni_xfer |
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1733 | hidnplayr | 276 | |
2390 | hidnplayr | 277 | test [edx + TCP_header.Flags], TH_SYN + TH_FIN + TH_RST + TH_URG |
278 | jnz .not_uni_xfer |
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1733 | hidnplayr | 279 | |
2390 | hidnplayr | 280 | test [edx + TCP_header.Flags], TH_ACK |
281 | jz .not_uni_xfer |
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1733 | hidnplayr | 282 | |
2390 | hidnplayr | 283 | mov eax, [edx + TCP_header.SequenceNumber] |
284 | cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
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285 | jne .not_uni_xfer |
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1733 | hidnplayr | 286 | |
2390 | hidnplayr | 287 | mov eax, dword [edx + TCP_header.Window] |
288 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
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289 | jne .not_uni_xfer |
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1733 | hidnplayr | 290 | |
2390 | hidnplayr | 291 | mov eax, [ebx + TCP_SOCKET.SND_NXT] |
292 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
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293 | jne .not_uni_xfer |
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1733 | hidnplayr | 294 | |
295 | ;--------------------------------------- |
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296 | ; check if we are sender in the uni-xfer |
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297 | |||
298 | ; If the following 4 conditions are all true, this segment is a pure ACK. |
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299 | ; |
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300 | ; - The segment contains no data. |
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2390 | hidnplayr | 301 | test ecx, ecx |
302 | jnz .not_sender |
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1733 | hidnplayr | 303 | |
304 | ; - The congestion window is greater than or equal to the current send window. |
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305 | ; This test is true only if the window is fully open, that is, the connection is not in the middle of slow start or congestion avoidance. |
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2390 | hidnplayr | 306 | mov eax, [ebx + TCP_SOCKET.SND_CWND] |
307 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
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308 | jb .not_uni_xfer |
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1733 | hidnplayr | 309 | |
310 | ; - The acknowledgment field in the segment is less than or equal to the maximum sequence number sent. |
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2390 | hidnplayr | 311 | mov eax, [edx + TCP_header.AckNumber] |
312 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
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313 | ja .not_uni_xfer |
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1733 | hidnplayr | 314 | |
315 | ; - The acknowledgment field in the segment is greater than the largest unacknowledged sequence number. |
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2390 | hidnplayr | 316 | sub eax, [ebx + TCP_SOCKET.SND_UNA] |
317 | jbe .not_uni_xfer |
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1733 | hidnplayr | 318 | |
2891 | hidnplayr | 319 | DEBUGF 1,"TCP_input: Header prediction: we are sender\n" |
1733 | hidnplayr | 320 | |
321 | ;--------------------------------- |
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322 | ; Packet is a pure ACK, process it |
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323 | |||
324 | ; Delete acknowledged bytes from send buffer |
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2390 | hidnplayr | 325 | pusha |
326 | mov ecx, eax |
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327 | lea eax, [ebx + STREAM_SOCKET.snd] |
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328 | call SOCKET_ring_free |
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329 | popa |
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1733 | hidnplayr | 330 | |
2930 | hidnplayr | 331 | ; Update RTT estimators |
332 | |||
333 | ; if ts_present |
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334 | ; mov eax, [esp + 4] ; timestamp when this segment was received |
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335 | ; sub eax, [ebx + TCP_SOCKET.ts_ecr] |
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336 | ; inc eax |
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337 | ; call TCP_xmit_timer |
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338 | |||
339 | ; else if (t_rtt && SEG_GT(ti_ack - t_rtsec)) |
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340 | ; mov eax, [ebx + t_rtt] |
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341 | ; call TCP_xmit_timer |
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342 | ; end if |
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343 | |||
1733 | hidnplayr | 344 | ; update window pointers |
2390 | hidnplayr | 345 | mov eax, [edx + TCP_header.AckNumber] |
346 | mov [ebx + TCP_SOCKET.SND_UNA], eax |
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1733 | hidnplayr | 347 | |
348 | ; Stop retransmit timer |
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2390 | hidnplayr | 349 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 |
1733 | hidnplayr | 350 | |
351 | ; Awaken waiting processes |
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2402 | hidnplayr | 352 | pusha |
353 | lea ecx, [ebx + SOCKET.mutex] |
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354 | call mutex_unlock |
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355 | popa |
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356 | |||
2390 | hidnplayr | 357 | mov eax, ebx |
358 | call SOCKET_notify_owner |
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1733 | hidnplayr | 359 | |
1763 | hidnplayr | 360 | ; Generate more output |
2390 | hidnplayr | 361 | call TCP_output |
1733 | hidnplayr | 362 | |
2390 | hidnplayr | 363 | jmp .drop_not_locked |
1763 | hidnplayr | 364 | |
1733 | hidnplayr | 365 | ;------------------------------------------------- |
366 | ; maybe we are the receiver in the uni-xfer then.. |
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367 | |||
368 | .not_sender: |
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369 | ; - The amount of data in the segment is greater than 0 (data count is in ecx) |
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370 | |||
371 | ; - The acknowledgment field equals the largest unacknowledged sequence number. This means no data is acknowledged by this segment. |
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2390 | hidnplayr | 372 | mov eax, [edx + TCP_header.AckNumber] |
373 | cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
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374 | jne .not_uni_xfer |
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1733 | hidnplayr | 375 | |
376 | ; - The reassembly list of out-of-order segments for the connection is empty (seg_next equals tp). |
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377 | |||
378 | ;;; TODO |
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379 | |||
2930 | hidnplayr | 380 | ; jnz .not_uni_xfer |
1733 | hidnplayr | 381 | |
382 | ; Complete processing of received data |
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383 | |||
2891 | hidnplayr | 384 | DEBUGF 1,"TCP_input: Header prediction: we are receiving %u bytes\n", ecx |
1733 | hidnplayr | 385 | |
2390 | hidnplayr | 386 | add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied |
1763 | hidnplayr | 387 | |
2390 | hidnplayr | 388 | movzx esi, [edx + TCP_header.DataOffset] |
389 | add esi, edx |
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390 | lea eax, [ebx + STREAM_SOCKET.rcv] |
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391 | call SOCKET_ring_write ; Add the data to the socket buffer |
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1733 | hidnplayr | 392 | |
2390 | hidnplayr | 393 | mov eax, ebx |
394 | call SOCKET_notify_owner |
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1733 | hidnplayr | 395 | |
2390 | hidnplayr | 396 | or [ebx + TCP_SOCKET.t_flags], TF_DELACK ; Set delayed ack flag |
1733 | hidnplayr | 397 | |
2390 | hidnplayr | 398 | jmp .drop |
1733 | hidnplayr | 399 | |
400 | |||
401 | |||
402 | |||
403 | |||
404 | |||
405 | ;-------------------------------------------------- |
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406 | ; Header prediction failed, do it the slow way |
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407 | |||
408 | .not_uni_xfer: |
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409 | |||
2891 | hidnplayr | 410 | DEBUGF 1,"TCP_input: Header prediction failed\n" |
1733 | hidnplayr | 411 | |
412 | ; Calculate receive window size |
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413 | |||
2362 | hidnplayr | 414 | ; mov eax, [ebx + STREAM_SOCKET.rcv.size] |
2305 | hidnplayr | 415 | ; neg eax |
416 | ; add eax, SOCKETBUFFSIZE |
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417 | ; mov edx, [ebx + TCP_SOCKET.RCV_ADV] |
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418 | ; sub edx, [ebx + TCP_SOCKET.RCV_NXT] |
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419 | ; cmp eax, edx |
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420 | ; jae @f |
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421 | ; mov eax, edx |
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422 | ; @@: |
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1733 | hidnplayr | 423 | |
2390 | hidnplayr | 424 | cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN |
425 | je .LISTEN |
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1733 | hidnplayr | 426 | |
2390 | hidnplayr | 427 | cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_SENT |
428 | je .SYN_SENT |
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1733 | hidnplayr | 429 | |
2891 | hidnplayr | 430 | DEBUGF 1,"TCP_input: state is not listen or syn_sent\n" |
1733 | hidnplayr | 431 | |
432 | ;-------------------------------------------- |
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433 | ; Protection Against Wrapped Sequence Numbers |
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434 | |||
435 | ; First, check if timestamp is present |
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436 | |||
1763 | hidnplayr | 437 | ;;;; TODO 602 |
1733 | hidnplayr | 438 | |
439 | ; Then, check if at least some bytes of data are within window |
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440 | |||
441 | ;;;; TODO |
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442 | |||
443 | |||
444 | |||
445 | |||
446 | |||
447 | |||
448 | |||
449 | |||
450 | ;---------------------------- |
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451 | ; trim any data not in window |
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452 | |||
453 | ; check for duplicate data at beginning of segment |
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454 | |||
2390 | hidnplayr | 455 | mov eax, [ebx + TCP_SOCKET.RCV_NXT] |
456 | sub eax, [edx + TCP_header.SequenceNumber] |
||
457 | jbe .no_duplicate |
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1733 | hidnplayr | 458 | |
2891 | hidnplayr | 459 | DEBUGF 1,"TCP_input: %u bytes duplicate data!\n", eax |
1763 | hidnplayr | 460 | |
2390 | hidnplayr | 461 | test [edx + TCP_header.Flags], TH_SYN |
462 | jz .no_dup_syn |
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1733 | hidnplayr | 463 | |
464 | ; remove duplicate syn |
||
465 | |||
2390 | hidnplayr | 466 | and [edx + TCP_header.Flags], not (TH_SYN) |
467 | inc [edx + TCP_header.SequenceNumber] |
||
1733 | hidnplayr | 468 | |
2390 | hidnplayr | 469 | cmp [edx + TCP_header.UrgentPointer], 1 |
470 | jbe @f |
||
471 | dec [edx + TCP_header.UrgentPointer] |
||
472 | jmp .dup_syn |
||
1733 | hidnplayr | 473 | @@: |
2390 | hidnplayr | 474 | and [edx + TCP_header.Flags], not (TH_URG) |
1838 | hidnplayr | 475 | .dup_syn: |
2390 | hidnplayr | 476 | dec eax |
1763 | hidnplayr | 477 | .no_dup_syn: |
1733 | hidnplayr | 478 | |
479 | ; eax holds number of bytes to drop |
||
480 | |||
481 | ; Check for entire duplicate packet |
||
482 | |||
2390 | hidnplayr | 483 | cmp eax, ecx |
484 | jae .duplicate |
||
1733 | hidnplayr | 485 | |
2891 | hidnplayr | 486 | DEBUGF 1,"TCP_input: Going to drop %u out of %u bytes\n", eax, ecx |
1830 | hidnplayr | 487 | |
1733 | hidnplayr | 488 | ;;; TODO: apply figure 28.30 |
489 | |||
490 | ; Check for duplicate FIN |
||
491 | |||
2390 | hidnplayr | 492 | test [edx + TCP_header.Flags], TH_FIN |
2891 | hidnplayr | 493 | jz .no_fin2 |
2390 | hidnplayr | 494 | inc ecx |
495 | cmp eax, ecx |
||
496 | jne @f |
||
1733 | hidnplayr | 497 | |
2390 | hidnplayr | 498 | mov eax, ecx |
499 | and [edx + TCP_header.Flags], not TH_FIN |
||
500 | or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
||
2891 | hidnplayr | 501 | dec ecx |
2390 | hidnplayr | 502 | jmp .no_duplicate |
2891 | hidnplayr | 503 | @@: |
504 | dec ecx |
||
505 | .no_fin2: |
||
1733 | hidnplayr | 506 | |
507 | ; Handle the case when a bound socket connects to itself |
||
2891 | hidnplayr | 508 | ; Allow packets with a SYN and an ACK to continue with the processing |
1733 | hidnplayr | 509 | |
510 | ;------------------------------------- |
||
511 | ; Generate duplicate ACK if nescessary |
||
512 | |||
513 | ; This code also handles simultaneous half-open or self-connects |
||
514 | |||
2390 | hidnplayr | 515 | test eax, eax |
516 | jnz .drop_after_ack |
||
1733 | hidnplayr | 517 | |
2390 | hidnplayr | 518 | cmp [edx + TCP_header.Flags], TH_ACK |
519 | jz .drop_after_ack |
||
1733 | hidnplayr | 520 | .duplicate: |
521 | |||
2891 | hidnplayr | 522 | DEBUGF 1,"TCP_input: Duplicate received\n" |
1733 | hidnplayr | 523 | |
524 | ;---------------------------------------- |
||
525 | ; Update statistics for duplicate packets |
||
526 | |||
527 | ;;; TODO |
||
528 | |||
2390 | hidnplayr | 529 | jmp .drop_after_ack |
1733 | hidnplayr | 530 | .no_duplicate: |
531 | |||
532 | ;----------------------------------------------- |
||
533 | ; Remove duplicate data and update urgent offset |
||
534 | |||
2390 | hidnplayr | 535 | add [edx + TCP_header.SequenceNumber], eax |
2891 | hidnplayr | 536 | sub ecx, eax ;;;;;;;; Checkme |
1733 | hidnplayr | 537 | |
2390 | hidnplayr | 538 | sub [edx + TCP_header.UrgentPointer], ax |
539 | ja @f |
||
1733 | hidnplayr | 540 | |
2390 | hidnplayr | 541 | and [edx + TCP_header.Flags], not (TH_URG) |
542 | mov [edx + TCP_header.UrgentPointer], 0 |
||
1733 | hidnplayr | 543 | @@: |
544 | |||
545 | ;-------------------------------------------------- |
||
546 | ; Handle data that arrives after process terminates |
||
547 | |||
2390 | hidnplayr | 548 | cmp [ebx + SOCKET.PID], 0 |
549 | ja @f |
||
1733 | hidnplayr | 550 | |
2390 | hidnplayr | 551 | cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT |
552 | jbe @f |
||
1733 | hidnplayr | 553 | |
2390 | hidnplayr | 554 | test ecx, ecx |
555 | jz @f |
||
1733 | hidnplayr | 556 | |
557 | ;;; Close the socket |
||
558 | ;;; update stats |
||
559 | |||
2390 | hidnplayr | 560 | jmp .drop_with_reset |
1733 | hidnplayr | 561 | @@: |
562 | |||
563 | ;---------------------------------------- |
||
564 | ; Remove data beyond right edge of window |
||
565 | |||
2390 | hidnplayr | 566 | mov eax, [edx + TCP_header.SequenceNumber] |
567 | add eax, ecx |
||
568 | sub eax, [ebx + TCP_SOCKET.RCV_NXT] |
||
569 | sub ax, [ebx + TCP_SOCKET.RCV_WND] |
||
1733 | hidnplayr | 570 | |
571 | ; eax now holds the number of bytes to drop |
||
572 | |||
2390 | hidnplayr | 573 | jbe .no_excess_data |
1733 | hidnplayr | 574 | |
575 | ;;; TODO: update stats |
||
576 | |||
2390 | hidnplayr | 577 | cmp eax, ecx |
578 | jb .dont_drop_all |
||
1733 | hidnplayr | 579 | |
580 | ;;; TODO 700-736 |
||
581 | |||
582 | .dont_drop_all: |
||
583 | |||
584 | .no_excess_data: |
||
585 | |||
586 | ;----------------- |
||
587 | ; Record timestamp |
||
588 | |||
589 | ;;; TODO 737-746 |
||
590 | |||
591 | |||
592 | ;------------------ |
||
593 | ; Process RST flags |
||
594 | |||
2390 | hidnplayr | 595 | test [edx + TCP_header.Flags], TH_RST |
2891 | hidnplayr | 596 | jz .no_rst |
1733 | hidnplayr | 597 | |
2891 | hidnplayr | 598 | DEBUGF 1,"TCP_input: Got an RST flag\n" |
1733 | hidnplayr | 599 | |
2390 | hidnplayr | 600 | mov eax, [ebx + TCP_SOCKET.t_state] |
601 | shl eax, 2 |
||
602 | jmp dword [eax + .rst_sw_list] |
||
1733 | hidnplayr | 603 | |
604 | .rst_sw_list: |
||
2891 | hidnplayr | 605 | dd .no_rst ; TCPS_CLOSED |
606 | dd .no_rst ; TCPS_LISTEN |
||
607 | dd .no_rst ; TCPS_SYN_SENT |
||
608 | dd .econnrefused ; TCPS_SYN_RECEIVED |
||
609 | dd .econnreset ; TCPS_ESTABLISHED |
||
610 | dd .econnreset ; TCPS_CLOSE_WAIT |
||
611 | dd .econnreset ; TCPS_FIN_WAIT_1 |
||
612 | dd .rst_close ; TCPS_CLOSING |
||
613 | dd .rst_close ; TCPS_LAST_ACK |
||
614 | dd .econnreset ; TCPS_FIN_WAIT_2 |
||
615 | dd .rst_close ; TCPS_TIMED_WAIT |
||
1733 | hidnplayr | 616 | |
617 | .econnrefused: |
||
2891 | hidnplayr | 618 | DEBUGF 1,"TCP_input: Connection refused\n" |
1733 | hidnplayr | 619 | |
2390 | hidnplayr | 620 | mov [ebx + SOCKET.errorcode], ECONNREFUSED |
621 | jmp .close |
||
1733 | hidnplayr | 622 | |
623 | .econnreset: |
||
2891 | hidnplayr | 624 | DEBUGF 1,"TCP_input: Connection reset\n" |
1733 | hidnplayr | 625 | |
2390 | hidnplayr | 626 | mov [ebx + SOCKET.errorcode], ECONNRESET |
1733 | hidnplayr | 627 | |
2882 | hidnplayr | 628 | .close: |
2891 | hidnplayr | 629 | DEBUGF 1,"TCP_input: Closing connection\n" |
1733 | hidnplayr | 630 | |
2390 | hidnplayr | 631 | mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSED |
2882 | hidnplayr | 632 | ;;; TODO: update stats (tcp drops) |
2390 | hidnplayr | 633 | mov eax, ebx |
634 | call TCP_close |
||
635 | jmp .drop |
||
1733 | hidnplayr | 636 | |
637 | .rst_close: |
||
2891 | hidnplayr | 638 | DEBUGF 1,"TCP_input: Closing with reset\n" |
1733 | hidnplayr | 639 | |
2390 | hidnplayr | 640 | mov eax, ebx |
641 | call TCP_close |
||
642 | jmp .drop |
||
1733 | hidnplayr | 643 | |
2891 | hidnplayr | 644 | .no_rst: |
1733 | hidnplayr | 645 | |
646 | ;-------------------------------------- |
||
647 | ; handle SYN-full and ACK-less segments |
||
648 | |||
2390 | hidnplayr | 649 | test [edx + TCP_header.Flags], TH_SYN |
650 | jz @f |
||
1733 | hidnplayr | 651 | |
2390 | hidnplayr | 652 | mov eax, ebx |
653 | mov ebx, ECONNRESET |
||
654 | call TCP_drop |
||
655 | jmp .drop_with_reset |
||
1733 | hidnplayr | 656 | @@: |
657 | |||
658 | ;--------------- |
||
659 | ; ACK processing |
||
660 | |||
2891 | hidnplayr | 661 | test [edx + TCP_header.Flags], TH_ACK |
662 | jz .drop |
||
663 | |||
2390 | hidnplayr | 664 | cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
665 | jnz .no_syn_rcv |
||
1733 | hidnplayr | 666 | |
2891 | hidnplayr | 667 | DEBUGF 1,"TCP_input: state=syn_received\n" |
1733 | hidnplayr | 668 | |
2390 | hidnplayr | 669 | mov eax, [edx + TCP_header.AckNumber] |
670 | cmp [ebx + TCP_SOCKET.SND_UNA], eax |
||
671 | ja .drop_with_reset |
||
672 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
||
673 | ja .drop_with_reset |
||
1733 | hidnplayr | 674 | |
2309 | hidnplayr | 675 | ;;; TODO: update stats |
676 | |||
2390 | hidnplayr | 677 | mov eax, ebx |
678 | call SOCKET_is_connected |
||
679 | mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
||
1831 | hidnplayr | 680 | |
681 | ; Do window scaling? |
||
682 | |||
2390 | hidnplayr | 683 | test [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE |
684 | jz @f |
||
685 | test [ebx + TCP_SOCKET.t_flags], TF_REQ_SCALE |
||
686 | jz @f |
||
1831 | hidnplayr | 687 | |
2390 | hidnplayr | 688 | push word [ebx + TCP_SOCKET.requested_s_scale] ; Set send and receive scale factors to the received values |
689 | pop word [ebx + TCP_SOCKET.SND_SCALE] |
||
1831 | hidnplayr | 690 | @@: |
691 | |||
2891 | hidnplayr | 692 | ;;; TODO: call TCP_reassemble |
1831 | hidnplayr | 693 | |
2390 | hidnplayr | 694 | mov eax, [edx + TCP_header.SequenceNumber] |
695 | dec eax |
||
696 | mov [ebx + TCP_SOCKET.SND_WL1], eax |
||
1831 | hidnplayr | 697 | |
1733 | hidnplayr | 698 | .no_syn_rcv: |
699 | |||
700 | ; check for duplicate ACK |
||
701 | |||
2390 | hidnplayr | 702 | mov eax, [edx + TCP_header.AckNumber] |
703 | cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
||
704 | ja .not_dup_ack |
||
1733 | hidnplayr | 705 | |
2390 | hidnplayr | 706 | test ecx, ecx |
707 | jnz .reset_dupacks |
||
1733 | hidnplayr | 708 | |
2390 | hidnplayr | 709 | mov eax, dword [edx + TCP_header.Window] |
710 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
||
711 | jne .reset_dupacks |
||
1733 | hidnplayr | 712 | |
2891 | hidnplayr | 713 | DEBUGF 1,"TCP_input: Processing duplicate ACK\n" |
1733 | hidnplayr | 714 | |
2390 | hidnplayr | 715 | cmp [ebx + TCP_SOCKET.timer_retransmission], 10000 ;;;; FIXME |
716 | ja @f |
||
1733 | hidnplayr | 717 | |
2390 | hidnplayr | 718 | mov eax, [edx + TCP_header.AckNumber] |
719 | cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
||
720 | je .dup_ack |
||
1763 | hidnplayr | 721 | |
722 | @@: |
||
2390 | hidnplayr | 723 | mov [ebx + TCP_SOCKET.t_dupacks], 0 |
724 | jmp .not_dup_ack |
||
1763 | hidnplayr | 725 | |
726 | .dup_ack: |
||
2390 | hidnplayr | 727 | inc [ebx + TCP_SOCKET.t_dupacks] |
728 | cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh |
||
729 | jne .no_re_xmit |
||
1763 | hidnplayr | 730 | |
2390 | hidnplayr | 731 | push [ebx + TCP_SOCKET.SND_NXT] ; >>>> |
1763 | hidnplayr | 732 | |
2390 | hidnplayr | 733 | mov eax, [ebx + TCP_SOCKET.SND_WND] |
734 | cmp eax, [ebx + TCP_SOCKET.SND_CWND] |
||
2866 | hidnplayr | 735 | cmova eax, [ebx + TCP_SOCKET.SND_CWND] |
2390 | hidnplayr | 736 | shr eax, 1 |
737 | push edx |
||
738 | xor edx, edx |
||
739 | div [ebx + TCP_SOCKET.t_maxseg] |
||
740 | cmp eax, 2 |
||
741 | jae @f |
||
742 | mov ax, 2 |
||
1763 | hidnplayr | 743 | @@: |
2390 | hidnplayr | 744 | mul [ebx + TCP_SOCKET.t_maxseg] |
745 | pop edx |
||
746 | mov [ebx + TCP_SOCKET.SND_SSTHRESH], eax |
||
1763 | hidnplayr | 747 | |
2390 | hidnplayr | 748 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; turn off retransmission timer |
749 | mov [ebx + TCP_SOCKET.t_rtt], 0 |
||
750 | mov eax, [edx + TCP_header.AckNumber] |
||
751 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
752 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
||
753 | mov [ebx + TCP_SOCKET.SND_CWND], eax |
||
1763 | hidnplayr | 754 | |
2390 | hidnplayr | 755 | mov eax, ebx |
756 | call TCP_output ; retransmit missing segment |
||
1763 | hidnplayr | 757 | |
2390 | hidnplayr | 758 | push edx |
759 | xor edx, edx |
||
760 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
||
761 | mul [ebx + TCP_SOCKET.t_dupacks] |
||
762 | pop edx |
||
763 | add eax, [ebx + TCP_SOCKET.SND_SSTHRESH] |
||
764 | mov [ebx + TCP_SOCKET.SND_CWND], eax |
||
1763 | hidnplayr | 765 | |
2390 | hidnplayr | 766 | pop eax ; <<<< |
767 | cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
||
768 | jb @f |
||
769 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1763 | hidnplayr | 770 | @@: |
771 | |||
2390 | hidnplayr | 772 | jmp .drop |
1733 | hidnplayr | 773 | |
774 | |||
1763 | hidnplayr | 775 | .no_re_xmit: |
2390 | hidnplayr | 776 | jbe .not_dup_ack |
1733 | hidnplayr | 777 | |
2891 | hidnplayr | 778 | DEBUGF 1,"TCP_input: Increasing congestion window\n" |
1733 | hidnplayr | 779 | |
2390 | hidnplayr | 780 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
781 | add [ebx + TCP_SOCKET.SND_CWND], eax |
||
1733 | hidnplayr | 782 | |
2390 | hidnplayr | 783 | mov eax, ebx |
784 | call TCP_output |
||
1733 | hidnplayr | 785 | |
2390 | hidnplayr | 786 | jmp .drop |
1733 | hidnplayr | 787 | |
788 | |||
1763 | hidnplayr | 789 | .not_dup_ack: |
790 | |||
1733 | hidnplayr | 791 | ;------------------------------------------------- |
792 | ; If the congestion window was inflated to account |
||
793 | ; for the other side's cached packets, retract it |
||
794 | |||
2390 | hidnplayr | 795 | mov eax, [ebx + TCP_SOCKET.SND_SSTHRESH] |
796 | cmp eax, [ebx + TCP_SOCKET.SND_CWND] |
||
797 | ja @f |
||
798 | cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh |
||
799 | jbe @f |
||
800 | mov [ebx + TCP_SOCKET.SND_CWND], eax |
||
1763 | hidnplayr | 801 | @@: |
1733 | hidnplayr | 802 | |
2390 | hidnplayr | 803 | mov [ebx + TCP_SOCKET.t_dupacks], 0 |
1733 | hidnplayr | 804 | |
2390 | hidnplayr | 805 | mov eax, [edx + TCP_header.AckNumber] |
806 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
||
807 | jbe @f |
||
1733 | hidnplayr | 808 | |
2390 | hidnplayr | 809 | ;;; TODO: update stats |
810 | jmp .drop_after_ack |
||
1733 | hidnplayr | 811 | |
1763 | hidnplayr | 812 | @@: |
1733 | hidnplayr | 813 | |
2390 | hidnplayr | 814 | mov edi, [edx + TCP_header.AckNumber] |
815 | sub edi, [ebx + TCP_SOCKET.SND_UNA] ; now we got the number of acked bytes in edi |
||
1733 | hidnplayr | 816 | |
2390 | hidnplayr | 817 | ;;; TODO: update stats |
1733 | hidnplayr | 818 | |
819 | |||
2891 | hidnplayr | 820 | DEBUGF 1,"TCP_input: acceptable ACK for %u bytes\n", edi |
1763 | hidnplayr | 821 | |
1733 | hidnplayr | 822 | ;------------------------------------------ |
823 | ; RTT measurements and retransmission timer |
||
824 | |||
2390 | hidnplayr | 825 | ;;;;; 912 - 926 |
1733 | hidnplayr | 826 | |
2390 | hidnplayr | 827 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 |
1733 | hidnplayr | 828 | |
2390 | hidnplayr | 829 | mov eax, [ebx + TCP_SOCKET.SND_MAX] |
830 | cmp eax, [edx + TCP_header.AckNumber] |
||
831 | je .all_outstanding |
||
832 | mov [ebx + TCP_SOCKET.timer_retransmission], 120 ;;;; TODO: correct this value (use a macro for it) |
||
2891 | hidnplayr | 833 | |
1733 | hidnplayr | 834 | .all_outstanding: |
2891 | hidnplayr | 835 | inc [ebx + TCP_SOCKET.sendalot] ; need output |
1733 | hidnplayr | 836 | |
837 | ;------------------------------------------- |
||
838 | ; Open congestion window in response to ACKs |
||
839 | |||
2390 | hidnplayr | 840 | mov esi, [ebx + TCP_SOCKET.SND_CWND] |
841 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
||
1733 | hidnplayr | 842 | |
2390 | hidnplayr | 843 | cmp esi, [ebx + TCP_SOCKET.SND_SSTHRESH] |
844 | jbe @f |
||
845 | push edx |
||
846 | push eax |
||
847 | mul eax |
||
848 | div esi |
||
849 | pop edx |
||
850 | shr edx, 3 |
||
851 | add eax, edx |
||
852 | pop edx |
||
1763 | hidnplayr | 853 | @@: |
1733 | hidnplayr | 854 | |
2390 | hidnplayr | 855 | add esi, eax |
1733 | hidnplayr | 856 | |
2390 | hidnplayr | 857 | push ecx |
858 | mov cl, [ebx + TCP_SOCKET.SND_SCALE] |
||
859 | mov eax, TCP_max_win |
||
860 | shl eax, cl |
||
861 | pop ecx |
||
1733 | hidnplayr | 862 | |
2390 | hidnplayr | 863 | cmp esi, eax |
2866 | hidnplayr | 864 | cmova esi, eax |
2390 | hidnplayr | 865 | mov [ebx + TCP_SOCKET.SND_CWND], esi |
1733 | hidnplayr | 866 | |
2891 | hidnplayr | 867 | ;------------------------------------------ |
868 | ; Remove acknowledged data from send buffer |
||
1733 | hidnplayr | 869 | |
2891 | hidnplayr | 870 | cmp edi, [ebx + STREAM_SOCKET.snd.size] |
871 | jbe .finiacked |
||
1733 | hidnplayr | 872 | |
2891 | hidnplayr | 873 | push ecx edx ebx |
874 | mov ecx, [ebx + STREAM_SOCKET.snd.size] |
||
875 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
876 | sub [ebx + TCP_SOCKET.SND_WND], ecx |
||
877 | call SOCKET_ring_free |
||
878 | pop ebx edx ecx |
||
1733 | hidnplayr | 879 | |
2891 | hidnplayr | 880 | DEBUGF 1,"TCP_input: our FIN is acked\n" |
881 | stc |
||
1763 | hidnplayr | 882 | |
2891 | hidnplayr | 883 | jmp .wakeup |
1763 | hidnplayr | 884 | |
2891 | hidnplayr | 885 | .finiacked: |
1763 | hidnplayr | 886 | |
2390 | hidnplayr | 887 | push ecx edx ebx |
888 | mov ecx, edi |
||
889 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
890 | call SOCKET_ring_free |
||
891 | pop ebx |
||
892 | sub [ebx + TCP_SOCKET.SND_WND], ecx |
||
893 | pop edx ecx |
||
1733 | hidnplayr | 894 | |
2891 | hidnplayr | 895 | DEBUGF 1,"TCP_input: our FIN is not acked\n" |
896 | clc |
||
897 | |||
898 | ;---------------------------------------- |
||
1733 | hidnplayr | 899 | ; Wake up process waiting on send buffer |
900 | |||
2891 | hidnplayr | 901 | .wakeup: |
902 | |||
903 | pushf |
||
2390 | hidnplayr | 904 | mov eax, ebx |
905 | call SOCKET_notify_owner |
||
1733 | hidnplayr | 906 | |
1831 | hidnplayr | 907 | ; Update TCPS |
1733 | hidnplayr | 908 | |
2390 | hidnplayr | 909 | mov eax, [edx + TCP_header.AckNumber] |
910 | mov [ebx + TCP_SOCKET.SND_UNA], eax |
||
911 | cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
||
912 | jb @f |
||
913 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1733 | hidnplayr | 914 | @@: |
915 | |||
2891 | hidnplayr | 916 | popf |
1733 | hidnplayr | 917 | |
918 | ; General ACK handling complete |
||
919 | ; Now do the state-specific ones |
||
920 | |||
2390 | hidnplayr | 921 | mov eax, [ebx + TCP_SOCKET.t_state] |
922 | jmp dword [eax*4 + .ACK_sw_list] |
||
1733 | hidnplayr | 923 | |
924 | .ACK_sw_list: |
||
2891 | hidnplayr | 925 | dd .ack_processed ; TCPS_CLOSED |
926 | dd .ack_processed ; TCPS_LISTEN |
||
927 | dd .ack_processed ; TCPS_SYN_SENT |
||
928 | dd .ack_processed ; TCPS_SYN_RECEIVED |
||
929 | dd .ack_processed ; TCPS_ESTABLISHED |
||
930 | dd .ack_processed ; TCPS_CLOSE_WAIT |
||
931 | dd .ack_fw1 ; TCPS_FIN_WAIT_1 |
||
932 | dd .ack_c ; TCPS_CLOSING |
||
933 | dd .ack_la ; TCPS_LAST_ACK |
||
934 | dd .ack_processed ; TCPS_FIN_WAIT_2 |
||
935 | dd .ack_tw ; TCPS_TIMED_WAIT |
||
1733 | hidnplayr | 936 | |
937 | |||
1772 | hidnplayr | 938 | .ack_fw1: |
2891 | hidnplayr | 939 | jnc .ack_processed |
1733 | hidnplayr | 940 | |
2390 | hidnplayr | 941 | test [ebx + SOCKET.state], SS_CANTRCVMORE |
942 | jnz @f |
||
943 | mov eax, ebx |
||
944 | call SOCKET_is_disconnected |
||
2891 | hidnplayr | 945 | ;;; mov [ebx + TCP_SOCKET.timer_timed_wait], TCP_time_max_idle ; FIXME |
1772 | hidnplayr | 946 | @@: |
1733 | hidnplayr | 947 | |
2390 | hidnplayr | 948 | mov [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2 |
949 | jmp .ack_processed |
||
1733 | hidnplayr | 950 | |
1772 | hidnplayr | 951 | .ack_c: |
2891 | hidnplayr | 952 | jnc .ack_processed |
1772 | hidnplayr | 953 | |
2390 | hidnplayr | 954 | mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
955 | mov eax, ebx |
||
956 | call TCP_cancel_timers |
||
957 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
||
958 | mov eax, ebx |
||
959 | call SOCKET_is_disconnected |
||
960 | jmp .ack_processed |
||
1733 | hidnplayr | 961 | |
1772 | hidnplayr | 962 | .ack_la: |
2891 | hidnplayr | 963 | jnc .ack_processed |
1733 | hidnplayr | 964 | |
2390 | hidnplayr | 965 | mov eax, ebx |
2882 | hidnplayr | 966 | call TCP_disconnect |
2390 | hidnplayr | 967 | jmp .drop |
1733 | hidnplayr | 968 | |
1772 | hidnplayr | 969 | .ack_tw: |
2390 | hidnplayr | 970 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
971 | jmp .drop_after_ack |
||
1733 | hidnplayr | 972 | |
2930 | hidnplayr | 973 | .reset_dupacks: ; We got a new ACK, reset duplicate ACK counter |
974 | mov [ebx + TCP_SOCKET.t_dupacks], 0 |
||
975 | jmp .ack_processed |
||
1733 | hidnplayr | 976 | |
1772 | hidnplayr | 977 | |
1733 | hidnplayr | 978 | |
2930 | hidnplayr | 979 | ;------------- |
980 | ; Passive Open |
||
1733 | hidnplayr | 981 | |
2930 | hidnplayr | 982 | align 4 |
983 | |||
984 | .accept_connection: |
||
985 | |||
986 | DEBUGF 1,"TCP_input: Accepting new connection\n" |
||
987 | |||
988 | pusha |
||
989 | lea ecx, [ebx + SOCKET.mutex] |
||
990 | call mutex_unlock |
||
991 | popa |
||
992 | |||
993 | push ecx edx esi edi ;;; |
||
994 | call SOCKET_fork |
||
995 | pop edi esi edx ecx |
||
996 | |||
997 | test eax, eax |
||
998 | jz .drop |
||
999 | |||
1000 | push dword [edi + 4] ; Ipv4 destination addres |
||
1001 | pop [eax + IP_SOCKET.LocalIP] |
||
1002 | |||
1003 | push [edx + TCP_header.DestinationPort] |
||
1004 | pop [eax + TCP_SOCKET.LocalPort] |
||
1005 | |||
1006 | mov [eax + TCP_SOCKET.t_state], TCPS_LISTEN |
||
1007 | mov ebx, eax |
||
1008 | |||
1009 | .LISTEN: |
||
1010 | |||
1011 | DEBUGF 1,"TCP_input: state=listen\n" |
||
1012 | |||
1013 | test [edx + TCP_header.Flags], TH_RST ;;; TODO: kill new socket on error |
||
1014 | jnz .drop |
||
1015 | |||
1016 | test [edx + TCP_header.Flags], TH_ACK |
||
1017 | jnz .drop_with_reset |
||
1018 | |||
1019 | test [edx + TCP_header.Flags], TH_SYN |
||
1020 | jz .drop |
||
1021 | |||
1022 | ;;; TODO: check if it's a broadcast or multicast, and drop if so |
||
1023 | |||
1024 | push dword [edi] ; Ipv4 source addres |
||
1025 | pop [ebx + IP_SOCKET.RemoteIP] |
||
1026 | |||
1027 | push [edx + TCP_header.SourcePort] |
||
1028 | pop [ebx + TCP_SOCKET.RemotePort] |
||
1029 | |||
1030 | push [edx + TCP_header.SequenceNumber] |
||
1031 | pop [ebx + TCP_SOCKET.IRS] |
||
1032 | |||
1033 | mov eax, [TCP_sequence_num] |
||
1034 | add [TCP_sequence_num], 64000 / 2 |
||
1035 | mov [ebx + TCP_SOCKET.ISS], eax |
||
1036 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1037 | |||
1038 | TCP_sendseqinit ebx |
||
1039 | TCP_rcvseqinit ebx |
||
1040 | |||
1041 | mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
||
1042 | mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
||
1043 | mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval ;;;; macro |
||
1044 | |||
1045 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
1046 | call SOCKET_ring_create |
||
1047 | |||
1048 | lea eax, [ebx + STREAM_SOCKET.rcv] |
||
1049 | call SOCKET_ring_create |
||
1050 | |||
1051 | ;;; call SOCKET_notify_owner |
||
1052 | |||
1053 | jmp .trim_then_step6 |
||
1054 | |||
1055 | |||
1056 | |||
1057 | |||
1058 | |||
1059 | |||
1060 | |||
1061 | |||
1062 | |||
1063 | |||
1064 | ;------------ |
||
1065 | ; Active Open |
||
1066 | |||
1067 | align 4 |
||
1068 | .SYN_SENT: |
||
1069 | |||
1070 | DEBUGF 1,"TCP_input: state=syn_sent\n" |
||
1071 | |||
1072 | test [edx + TCP_header.Flags], TH_ACK |
||
1073 | jz @f |
||
1074 | |||
1075 | mov eax, [edx + TCP_header.AckNumber] |
||
1076 | cmp eax, [ebx + TCP_SOCKET.ISS] |
||
1077 | jbe .drop_with_reset |
||
1078 | |||
1079 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
||
1080 | ja .drop_with_reset |
||
1081 | @@: |
||
1082 | |||
1083 | test [edx + TCP_header.Flags], TH_RST |
||
1084 | jz @f |
||
1085 | |||
1086 | test [edx + TCP_header.Flags], TH_ACK |
||
1087 | jz .drop |
||
1088 | |||
1089 | mov eax, ebx |
||
1090 | mov ebx, ECONNREFUSED |
||
1091 | call TCP_drop |
||
1092 | |||
1093 | jmp .drop |
||
1094 | @@: |
||
1095 | |||
1096 | test [edx + TCP_header.Flags], TH_SYN |
||
1097 | jz .drop |
||
1098 | |||
1099 | ; at this point, segment seems to be valid |
||
1100 | |||
1101 | test [edx + TCP_header.Flags], TH_ACK |
||
1102 | jz .no_syn_ack |
||
1103 | |||
1104 | ; now, process received SYN in response to an active open |
||
1105 | |||
1106 | mov eax, [edx + TCP_header.AckNumber] |
||
1107 | mov [ebx + TCP_SOCKET.SND_UNA], eax |
||
1108 | cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
||
1109 | jbe @f |
||
1110 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1111 | @@: |
||
1112 | |||
1113 | .no_syn_ack: |
||
1114 | |||
1115 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; disable retransmission |
||
1116 | |||
1117 | push [edx + TCP_header.SequenceNumber] |
||
1118 | pop [ebx + TCP_SOCKET.IRS] |
||
1119 | |||
1120 | TCP_rcvseqinit ebx |
||
1121 | |||
1122 | or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
||
1123 | |||
1124 | mov eax, [ebx + TCP_SOCKET.SND_UNA] |
||
1125 | cmp eax, [ebx + TCP_SOCKET.ISS] |
||
1126 | jbe .simultaneous_open |
||
1127 | |||
1128 | test [edx + TCP_header.Flags], TH_ACK |
||
1129 | jz .simultaneous_open |
||
1130 | |||
1131 | DEBUGF 1,"TCP_input: active open\n" |
||
1132 | |||
1133 | ;;; TODO: update stats |
||
1134 | |||
1135 | ; set socket state to connected |
||
1136 | mov [ebx + SOCKET.state], SS_ISCONNECTED |
||
1137 | mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
||
1138 | |||
1139 | ;;; TODO: check if we should scale the connection (567-572) |
||
1140 | mov [ebx + TCP_SOCKET.SND_SCALE], 0 |
||
1141 | |||
1142 | ;;; TODO: update RTT estimators |
||
1143 | |||
1144 | jmp .trim_then_step6 |
||
1145 | |||
1146 | .simultaneous_open: |
||
1147 | |||
1148 | DEBUGF 1,"TCP_input: simultaneous open\n" |
||
1149 | ; We have received a syn but no ACK, so we are having a simultaneous open.. |
||
1150 | mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
||
1151 | |||
1152 | ;------------------------------------- |
||
1153 | ; Common processing for receipt of SYN |
||
1154 | |||
1155 | .trim_then_step6: |
||
1156 | |||
1157 | inc [edx + TCP_header.SequenceNumber] |
||
1158 | |||
1159 | ;;; TODO: Drop any received data that follows receive window (590) |
||
1160 | |||
1161 | mov eax, [edx + TCP_header.SequenceNumber] |
||
1162 | mov [ebx + TCP_SOCKET.RCV_UP], eax |
||
1163 | dec eax |
||
1164 | mov [ebx + TCP_SOCKET.SND_WL1], eax |
||
1165 | |||
1166 | jmp .ack_processed |
||
1167 | |||
1168 | |||
1169 | |||
2390 | hidnplayr | 1170 | .ack_processed: ; (step 6) |
1733 | hidnplayr | 1171 | |
2891 | hidnplayr | 1172 | DEBUGF 1,"TCP_input: ACK processed\n" |
1733 | hidnplayr | 1173 | |
1174 | ;---------------------------------------------- |
||
1175 | ; check if we need to update window information |
||
1176 | |||
2390 | hidnplayr | 1177 | test [edx + TCP_header.Flags], TH_ACK |
1178 | jz .no_window_update |
||
1733 | hidnplayr | 1179 | |
2390 | hidnplayr | 1180 | mov eax, [ebx + TCP_SOCKET.SND_WL1] |
1181 | cmp eax, [edx + TCP_header.SequenceNumber] |
||
1182 | jb .update_window |
||
1183 | ja @f |
||
1733 | hidnplayr | 1184 | |
2390 | hidnplayr | 1185 | mov eax, [ebx + TCP_SOCKET.SND_WL2] |
1186 | cmp eax, [edx + TCP_header.AckNumber] |
||
1187 | jb .update_window |
||
1188 | ja .no_window_update |
||
1733 | hidnplayr | 1189 | @@: |
1190 | |||
2390 | hidnplayr | 1191 | mov eax, [ebx + TCP_SOCKET.SND_WL2] |
1192 | cmp eax, [edx + TCP_header.AckNumber] |
||
1193 | jne .no_window_update |
||
1733 | hidnplayr | 1194 | |
2390 | hidnplayr | 1195 | mov eax, dword [edx + TCP_header.Window] |
1196 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
||
1197 | jbe .no_window_update |
||
1733 | hidnplayr | 1198 | |
1199 | .update_window: |
||
1200 | |||
2612 | hidnplayr | 1201 | ;;; TODO: Keep track of pure window updates |
1733 | hidnplayr | 1202 | |
2390 | hidnplayr | 1203 | mov eax, dword [edx + TCP_header.Window] |
1204 | cmp eax, [ebx + TCP_SOCKET.max_sndwnd] |
||
1205 | jbe @f |
||
1206 | mov [ebx + TCP_SOCKET.max_sndwnd], eax |
||
1733 | hidnplayr | 1207 | @@: |
2390 | hidnplayr | 1208 | mov [ebx + TCP_SOCKET.SND_WND], eax |
1733 | hidnplayr | 1209 | |
2891 | hidnplayr | 1210 | DEBUGF 1,"TCP_input: Updating window to %u\n", eax |
2612 | hidnplayr | 1211 | |
2390 | hidnplayr | 1212 | push [edx + TCP_header.SequenceNumber] |
1213 | pop [ebx + TCP_SOCKET.SND_WL1] |
||
1733 | hidnplayr | 1214 | |
2390 | hidnplayr | 1215 | push [edx + TCP_header.AckNumber] |
1216 | pop [ebx + TCP_SOCKET.SND_WL2] |
||
1733 | hidnplayr | 1217 | |
2891 | hidnplayr | 1218 | inc [ebx + TCP_SOCKET.sendalot] |
1733 | hidnplayr | 1219 | |
1220 | .no_window_update: |
||
1221 | |||
1222 | |||
1223 | |||
1224 | |||
1225 | |||
1226 | |||
1227 | |||
1228 | ;----------------- |
||
1229 | ; process URG flag |
||
1230 | |||
2390 | hidnplayr | 1231 | test [edx + TCP_header.Flags], TH_URG |
1232 | jz .not_urgent |
||
1733 | hidnplayr | 1233 | |
2390 | hidnplayr | 1234 | cmp [edx + TCP_header.UrgentPointer], 0 |
1235 | jz .not_urgent |
||
1733 | hidnplayr | 1236 | |
2390 | hidnplayr | 1237 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1238 | je .not_urgent |
||
1733 | hidnplayr | 1239 | |
1240 | ; Ignore bogus urgent offsets |
||
1241 | |||
2390 | hidnplayr | 1242 | ;;; 1040-1050 |
1733 | hidnplayr | 1243 | |
2390 | hidnplayr | 1244 | movzx eax, [edx + TCP_header.UrgentPointer] |
1245 | add eax, [ebx + STREAM_SOCKET.rcv.size] |
||
1246 | cmp eax, SOCKET_MAXDATA |
||
1247 | jbe .not_urgent |
||
1733 | hidnplayr | 1248 | |
2390 | hidnplayr | 1249 | mov [edx + TCP_header.UrgentPointer], 0 |
1250 | and [edx + TCP_header.Flags], not (TH_URG) |
||
1251 | jmp .do_data |
||
1733 | hidnplayr | 1252 | |
1253 | .not_urgent: |
||
1254 | |||
1255 | ; processing of received urgent pointer |
||
1256 | |||
2390 | hidnplayr | 1257 | ;;; TODO (1051-1093) |
1733 | hidnplayr | 1258 | |
1259 | |||
2891 | hidnplayr | 1260 | ;--------------------------------------- |
1261 | ; process the data in the segment (1094) |
||
1733 | hidnplayr | 1262 | |
1263 | .do_data: |
||
1264 | |||
2891 | hidnplayr | 1265 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1266 | jae .final_processing |
||
1733 | hidnplayr | 1267 | |
2390 | hidnplayr | 1268 | test [edx + TCP_header.Flags], TH_FIN |
2891 | hidnplayr | 1269 | jnz @f |
1733 | hidnplayr | 1270 | |
2390 | hidnplayr | 1271 | test ecx, ecx |
2891 | hidnplayr | 1272 | jnz .final_processing |
1273 | @@: |
||
1733 | hidnplayr | 1274 | |
2891 | hidnplayr | 1275 | ; call TCP_reassemble ;;; TODO |
1733 | hidnplayr | 1276 | |
1277 | ;--------------- |
||
1278 | ; FIN processing |
||
1279 | |||
2891 | hidnplayr | 1280 | test [edx + TCP_header.Flags], TH_FIN |
2930 | hidnplayr | 1281 | jz .final_processing |
1733 | hidnplayr | 1282 | |
2891 | hidnplayr | 1283 | DEBUGF 1,"TCP_input: Processing FIN\n" |
1733 | hidnplayr | 1284 | |
2891 | hidnplayr | 1285 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1286 | jae .not_first_fin |
||
1774 | hidnplayr | 1287 | |
2891 | hidnplayr | 1288 | DEBUGF 1,"TCP_input: First FIN for this connection\n" |
1774 | hidnplayr | 1289 | |
2390 | hidnplayr | 1290 | mov eax, ebx |
1291 | call SOCKET_cant_recv_more |
||
1774 | hidnplayr | 1292 | |
2390 | hidnplayr | 1293 | mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
1294 | inc [ebx + TCP_SOCKET.RCV_NXT] |
||
1774 | hidnplayr | 1295 | |
1296 | .not_first_fin: |
||
2390 | hidnplayr | 1297 | mov eax, [ebx + TCP_SOCKET.t_state] |
1298 | shl eax, 2 |
||
1299 | jmp dword [eax + .FIN_sw_list] |
||
1733 | hidnplayr | 1300 | |
1301 | .FIN_sw_list: |
||
2930 | hidnplayr | 1302 | dd .final_processing ; TCPS_CLOSED |
1303 | dd .final_processing ; TCPS_LISTEN |
||
1304 | dd .final_processing ; TCPS_SYN_SENT |
||
2891 | hidnplayr | 1305 | dd .fin_syn_est ; TCPS_SYN_RECEIVED |
1306 | dd .fin_syn_est ; TCPS_ESTABLISHED |
||
2930 | hidnplayr | 1307 | dd .final_processing ; TCPS_CLOSE_WAIT |
2891 | hidnplayr | 1308 | dd .fin_wait1 ; TCPS_FIN_WAIT_1 |
2930 | hidnplayr | 1309 | dd .final_processing ; TCPS_CLOSING |
1310 | dd .final_processing ; TCPS_LAST_ACK |
||
2891 | hidnplayr | 1311 | dd .fin_wait2 ; TCPS_FIN_WAIT_2 |
1312 | dd .fin_timed ; TCPS_TIMED_WAIT |
||
1733 | hidnplayr | 1313 | |
1314 | .fin_syn_est: |
||
1315 | |||
2390 | hidnplayr | 1316 | mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT |
2930 | hidnplayr | 1317 | jmp .final_processing |
1733 | hidnplayr | 1318 | |
1319 | .fin_wait1: |
||
1320 | |||
2390 | hidnplayr | 1321 | mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSING |
2930 | hidnplayr | 1322 | jmp .final_processing |
1733 | hidnplayr | 1323 | |
1324 | .fin_wait2: |
||
1325 | |||
2390 | hidnplayr | 1326 | mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1327 | mov eax, ebx |
||
1328 | call TCP_cancel_timers |
||
1329 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
||
1330 | call SOCKET_is_disconnected |
||
2930 | hidnplayr | 1331 | jmp .final_processing |
1733 | hidnplayr | 1332 | |
1333 | .fin_timed: |
||
2390 | hidnplayr | 1334 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
2930 | hidnplayr | 1335 | jmp .final_processing |
1733 | hidnplayr | 1336 | |
1337 | |||
2930 | hidnplayr | 1338 | .drop_after_ack: |
1339 | DEBUGF 1,"TCP_input: Drop after ACK\n" |
||
1733 | hidnplayr | 1340 | |
2930 | hidnplayr | 1341 | push edx ebx |
2891 | hidnplayr | 1342 | lea ecx, [ebx + SOCKET.mutex] |
1343 | call mutex_unlock |
||
2930 | hidnplayr | 1344 | pop eax edx |
2891 | hidnplayr | 1345 | |
2930 | hidnplayr | 1346 | test [edx + TCP_header.Flags], TH_RST |
1347 | jnz .dumpit |
||
1733 | hidnplayr | 1348 | |
2930 | hidnplayr | 1349 | or [eax + TCP_SOCKET.t_flags], TF_ACKNOW |
1350 | jmp .need_output |
||
2891 | hidnplayr | 1351 | |
1733 | hidnplayr | 1352 | |
2891 | hidnplayr | 1353 | |
2930 | hidnplayr | 1354 | .drop_with_reset: |
1355 | DEBUGF 1,"TCP_input: Drop with reset\n" |
||
1356 | |||
1357 | push ebx edx |
||
2402 | hidnplayr | 1358 | lea ecx, [ebx + SOCKET.mutex] |
1359 | call mutex_unlock |
||
2930 | hidnplayr | 1360 | pop edx ebx |
1733 | hidnplayr | 1361 | |
2930 | hidnplayr | 1362 | test [edx + TCP_header.Flags], TH_RST |
1363 | jnz .dumpit |
||
1733 | hidnplayr | 1364 | |
2930 | hidnplayr | 1365 | ;;; if its a multicast/broadcast, also drop |
1733 | hidnplayr | 1366 | |
2930 | hidnplayr | 1367 | test [edx + TCP_header.Flags], TH_ACK |
1368 | jnz .respond_ack |
||
1733 | hidnplayr | 1369 | |
2930 | hidnplayr | 1370 | test [edx + TCP_header.Flags], TH_SYN |
1371 | jnz .respond_syn |
||
1372 | jmp .dumpit |
||
1733 | hidnplayr | 1373 | |
2930 | hidnplayr | 1374 | ;----------------- |
1375 | ; Final processing |
||
1733 | hidnplayr | 1376 | |
2930 | hidnplayr | 1377 | .final_processing: |
1378 | DEBUGF 1,"TCP_input: Final processing\n" |
||
1733 | hidnplayr | 1379 | |
2930 | hidnplayr | 1380 | push ebx |
1381 | lea ecx, [ebx + SOCKET.mutex] |
||
1382 | call mutex_unlock |
||
1383 | pop eax |
||
1733 | hidnplayr | 1384 | |
2930 | hidnplayr | 1385 | cmp [eax + TCP_SOCKET.sendalot], 0 |
1386 | jne .need_output |
||
1733 | hidnplayr | 1387 | |
2930 | hidnplayr | 1388 | test [eax + TCP_SOCKET.t_flags], TF_ACKNOW |
1389 | jz .dumpit |
||
1390 | DEBUGF 1,"TCP_input: ACK now!\n" |
||
1733 | hidnplayr | 1391 | |
2930 | hidnplayr | 1392 | .need_output: |
1393 | call TCP_output |
||
1733 | hidnplayr | 1394 | |
2930 | hidnplayr | 1395 | .dumpit: |
1396 | DEBUGF 1,"TCP_input: dumping\n" |
||
1733 | hidnplayr | 1397 | |
2390 | hidnplayr | 1398 | call kernel_free |
1399 | add esp, 4 |
||
1400 | ret |
||
1733 | hidnplayr | 1401 | |
1402 | |||
1403 | |||
1404 | |||
1405 | |||
1406 | .respond_ack: |
||
1407 | |||
2390 | hidnplayr | 1408 | push ebx |
1409 | mov cl, TH_RST |
||
1410 | call TCP_respond_socket |
||
1411 | pop ebx |
||
1412 | jmp .destroy_new_socket |
||
1733 | hidnplayr | 1413 | |
1414 | |||
1415 | .respond_syn: |
||
1416 | |||
2390 | hidnplayr | 1417 | push ebx |
1418 | mov cl, TH_RST + TH_ACK |
||
1419 | call TCP_respond_socket |
||
1420 | pop ebx |
||
1421 | jmp .destroy_new_socket |
||
1733 | hidnplayr | 1422 | |
1423 | |||
1424 | |||
1425 | |||
1426 | |||
1427 | ;----- |
||
1428 | ; Drop |
||
1429 | |||
2930 | hidnplayr | 1430 | .drop: |
1733 | hidnplayr | 1431 | |
2402 | hidnplayr | 1432 | pusha |
1433 | lea ecx, [ebx + SOCKET.mutex] |
||
1434 | call mutex_unlock |
||
1435 | popa |
||
1733 | hidnplayr | 1436 | |
2930 | hidnplayr | 1437 | .drop_not_locked: |
1733 | hidnplayr | 1438 | |
2891 | hidnplayr | 1439 | DEBUGF 1,"TCP_input: Dropping packet\n" |
1733 | hidnplayr | 1440 | |
2390 | hidnplayr | 1441 | ;;;; If debugging options are enabled, output the packet somwhere |
1733 | hidnplayr | 1442 | |
1443 | .destroy_new_socket: |
||
1444 | |||
2390 | hidnplayr | 1445 | ;;;; kill the newly created socket |
1733 | hidnplayr | 1446 | |
2930 | hidnplayr | 1447 | .drop_no_socket: |
1448 | DEBUGF 1,"TCP_input: Drop (no socket)\n" |
||
1449 | |||
2390 | hidnplayr | 1450 | call kernel_free |
1451 | add esp, 4 |
||
2600 | hidnplayr | 1452 | ret |
1453 | |||
2930 | hidnplayr | 1454 | .drop_with_reset_no_socket: |
2600 | hidnplayr | 1455 | |
2891 | hidnplayr | 1456 | DEBUGF 1,"TCP_input: Drop with reset (no socket)\n" |
2600 | hidnplayr | 1457 | |
1458 | test [edx + TCP_header.Flags], TH_RST |
||
1459 | jnz .drop_no_socket |
||
1460 | |||
1461 | ;;; if its a multicast/broadcast, also drop |
||
1462 | |||
1463 | test [edx + TCP_header.Flags], TH_ACK |
||
1464 | jnz .respond_seg_ack |
||
1465 | |||
1466 | test [edx + TCP_header.Flags], TH_SYN |
||
1467 | jnz .respond_seg_syn |
||
1468 | |||
2930 | hidnplayr | 1469 | jmp .drop_no_socket |
2600 | hidnplayr | 1470 | |
1471 | .respond_seg_ack: |
||
1472 | |||
1473 | mov cl, TH_RST |
||
1474 | call TCP_respond_segment |
||
1475 | jmp .drop_no_socket |
||
1476 | |||
1477 | .respond_seg_syn: |
||
1478 | |||
1479 | mov cl, TH_RST + TH_ACK |
||
1480 | call TCP_respond_segment |
||
1481 | jmp .drop_no_socket |