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1763 | hidnplayr | 1 | ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |
2 | ;; ;; |
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3251 | hidnplayr | 3 | ;; Copyright (C) KolibriOS team 2004-2013. 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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16 | |||
17 | $Revision: 3406 $ |
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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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3251 | hidnplayr | 23 | ; Add a segment to the incoming TCP queue |
24 | ; |
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1733 | hidnplayr | 25 | ; IN: [esp] = ptr to buffer |
3252 | hidnplayr | 26 | ; [esp+4] = buffer size (dont care) |
1733 | hidnplayr | 27 | ; ebx = ptr to device struct |
28 | ; ecx = segment size |
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2310 | hidnplayr | 29 | ; esi = ptr to TCP segment |
2308 | hidnplayr | 30 | ; edi = ptr to ipv4 source address, followed by ipv4 dest address |
1733 | hidnplayr | 31 | ; |
32 | ; OUT: / |
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33 | ; |
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34 | ;----------------------------------------------------------------- |
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1830 | hidnplayr | 35 | |
1733 | hidnplayr | 36 | align 4 |
37 | TCP_input: |
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38 | |||
3252 | hidnplayr | 39 | ; record the current time |
40 | mov eax, [timer_ticks] ; in 1/100 seconds |
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41 | mov [esp + 4], eax |
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42 | |||
3251 | hidnplayr | 43 | push ebx ecx esi edi ; mind the order |
44 | mov esi, esp |
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45 | |||
46 | pushf |
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2942 | hidnplayr | 47 | cli |
3251 | hidnplayr | 48 | add_to_queue TCP_queue, TCP_QUEUE_SIZE, sizeof.TCP_queue_entry, .fail |
49 | popf |
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50 | |||
51 | add esp, sizeof.TCP_queue_entry |
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3389 | hidnplayr | 52 | |
53 | mov [check_idle_semaphore], 5 |
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54 | xor edx, edx |
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55 | mov eax, [TCP_input_event] |
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56 | mov ebx, [eax + EVENT.id] |
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57 | xor esi, esi |
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58 | call raise_event |
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59 | |||
3251 | hidnplayr | 60 | ret |
61 | |||
62 | .fail: |
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3293 | hidnplayr | 63 | popf |
3251 | hidnplayr | 64 | DEBUGF 2, "TCP incoming queue is full, discarding packet!\n" |
65 | |||
3275 | hidnplayr | 66 | inc [TCP_segments_missed] ; FIXME: use correct interface |
67 | |||
3251 | hidnplayr | 68 | add esp, sizeof.TCP_queue_entry - 8 |
69 | call kernel_free |
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70 | add esp, 4 |
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3389 | hidnplayr | 71 | |
3251 | hidnplayr | 72 | ret |
73 | |||
74 | |||
75 | |||
3406 | hidnplayr | 76 | |
3251 | hidnplayr | 77 | align 4 |
78 | TCP_process_input: |
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79 | |||
3389 | hidnplayr | 80 | xor esi, esi |
81 | mov ecx, MANUAL_DESTROY |
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82 | call create_event |
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83 | mov [TCP_input_event], eax |
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84 | |||
3406 | hidnplayr | 85 | .wait: |
3389 | hidnplayr | 86 | mov eax, [TCP_input_event] |
87 | call wait_event |
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3251 | hidnplayr | 88 | |
3406 | hidnplayr | 89 | .loop: |
90 | get_from_queue TCP_queue, TCP_QUEUE_SIZE, sizeof.TCP_queue_entry, .wait |
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3389 | hidnplayr | 91 | |
3406 | hidnplayr | 92 | push [esi + TCP_queue_entry.timestamp] |
3251 | hidnplayr | 93 | push [esi + TCP_queue_entry.buffer_ptr] |
94 | |||
95 | mov ebx, [esi + TCP_queue_entry.device_ptr] |
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96 | mov ecx, [esi + TCP_queue_entry.segment_size] |
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3406 | hidnplayr | 97 | mov edi, [esi + TCP_queue_entry.ip_ptr] ; ptr to ipv4 source address, followed by ipv4 destination address |
3251 | hidnplayr | 98 | mov esi, [esi + TCP_queue_entry.segment_ptr] ; change esi last |
99 | |||
2957 | hidnplayr | 100 | DEBUGF 1,"TCP_input: size=%u time=%d\n", ecx, [timer_ticks] |
1733 | hidnplayr | 101 | |
3406 | hidnplayr | 102 | mov edx, esi |
103 | |||
104 | cmp ebx, LOOPBACK_DEVICE |
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105 | je .checksum_ok |
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106 | |||
3252 | hidnplayr | 107 | ; re-calculate the checksum (if not already done by hw) |
2930 | hidnplayr | 108 | ; test [ebx + NET_DEVICE.hwacc], HWACC_TCP_IPv4_IN |
109 | ; jnz .checksum_ok |
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110 | |||
2390 | hidnplayr | 111 | push ecx esi |
112 | pushw [esi + TCP_header.Checksum] |
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113 | mov [esi + TCP_header.Checksum], 0 |
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114 | TCP_checksum (edi), (edi+4) |
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2937 | hidnplayr | 115 | pop cx ; previous checksum |
2390 | hidnplayr | 116 | cmp cx, dx |
117 | pop edx ecx |
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2600 | hidnplayr | 118 | jne .drop_no_socket |
2930 | hidnplayr | 119 | .checksum_ok: |
1733 | hidnplayr | 120 | |
2930 | hidnplayr | 121 | ; Verify the data offset |
2390 | hidnplayr | 122 | and [edx + TCP_header.DataOffset], 0xf0 ; Calculate TCP segment header size (throwing away unused reserved bits in TCP header) |
123 | shr [edx + TCP_header.DataOffset], 2 |
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124 | 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 | 125 | jb .drop_no_socket ; If not, drop the packet |
1733 | hidnplayr | 126 | |
2390 | hidnplayr | 127 | movzx eax, [edx + TCP_header.DataOffset] |
128 | sub ecx, eax ; substract TCP header size from total segment size |
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2600 | hidnplayr | 129 | jb .drop_no_socket ; If total segment size is less then the advertised header size, drop packet |
2891 | hidnplayr | 130 | DEBUGF 1,"TCP_input: %u bytes of data\n", ecx |
1733 | hidnplayr | 131 | |
132 | ;------------------------------------------- |
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133 | ; Convert Big-endian values to little endian |
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134 | |||
2390 | hidnplayr | 135 | ntohd [edx + TCP_header.SequenceNumber] |
136 | ntohd [edx + TCP_header.AckNumber] |
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1733 | hidnplayr | 137 | |
2390 | hidnplayr | 138 | ntohw [edx + TCP_header.Window] |
139 | ntohw [edx + TCP_header.UrgentPointer] |
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1733 | hidnplayr | 140 | |
2930 | hidnplayr | 141 | ;------------------------ |
142 | ; Find the socket pointer |
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1733 | hidnplayr | 143 | |
144 | ; IP Packet TCP Destination Port = local Port |
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145 | ; (IP Packet SenderAddress = Remote IP) OR (Remote IP = 0) |
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2309 | hidnplayr | 146 | ; (IP Packet TCP Source Port = remote Port) OR (remote Port = 0) |
1733 | hidnplayr | 147 | |
2937 | hidnplayr | 148 | .findpcb: |
2390 | hidnplayr | 149 | mov ebx, net_sockets |
150 | mov si, [edx + TCP_header.DestinationPort] |
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1733 | hidnplayr | 151 | |
152 | .socket_loop: |
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2390 | hidnplayr | 153 | mov ebx, [ebx + SOCKET.NextPtr] |
154 | or ebx, ebx |
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3275 | hidnplayr | 155 | jz .respond_seg_reset |
1733 | hidnplayr | 156 | |
2390 | hidnplayr | 157 | cmp [ebx + SOCKET.Domain], AF_INET4 |
158 | jne .socket_loop |
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1733 | hidnplayr | 159 | |
2390 | hidnplayr | 160 | cmp [ebx + SOCKET.Protocol], IP_PROTO_TCP |
161 | jne .socket_loop |
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1733 | hidnplayr | 162 | |
2390 | hidnplayr | 163 | cmp [ebx + TCP_SOCKET.LocalPort], si |
164 | jne .socket_loop |
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1733 | hidnplayr | 165 | |
2390 | hidnplayr | 166 | mov eax, [ebx + IP_SOCKET.RemoteIP] |
3406 | hidnplayr | 167 | cmp eax, [edi] ; Ipv4 source address |
2390 | hidnplayr | 168 | je @f |
169 | test eax, eax |
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170 | jnz .socket_loop |
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1733 | hidnplayr | 171 | @@: |
172 | |||
2390 | hidnplayr | 173 | mov ax, [ebx + TCP_SOCKET.RemotePort] |
174 | cmp [edx + TCP_header.SourcePort], ax |
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175 | je .found_socket |
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176 | test ax, ax |
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177 | jnz .socket_loop |
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178 | .found_socket: ; ebx now contains the socketpointer |
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2891 | hidnplayr | 179 | 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 | 180 | |
2930 | hidnplayr | 181 | ;------------- |
2890 | hidnplayr | 182 | ; update stats |
2930 | hidnplayr | 183 | |
2890 | hidnplayr | 184 | inc [TCP_segments_rx] ; FIXME: correct interface? |
1733 | hidnplayr | 185 | |
186 | ;---------------------------- |
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187 | ; Check if socket isnt closed |
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188 | |||
2390 | hidnplayr | 189 | cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSED |
2937 | hidnplayr | 190 | je .drop_no_socket |
1733 | hidnplayr | 191 | |
192 | ;---------------- |
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193 | ; Lock the socket |
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194 | |||
2402 | hidnplayr | 195 | pusha |
196 | lea ecx, [ebx + SOCKET.mutex] |
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197 | call mutex_lock |
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198 | popa |
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1830 | hidnplayr | 199 | |
2891 | hidnplayr | 200 | DEBUGF 1,"TCP_input: socket locked\n" |
1733 | hidnplayr | 201 | |
2937 | hidnplayr | 202 | ;--------------------------- |
203 | ; disable all temporary bits |
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2891 | hidnplayr | 204 | |
2937 | hidnplayr | 205 | mov [ebx + TCP_SOCKET.temp_bits], 0 |
2891 | hidnplayr | 206 | |
1733 | hidnplayr | 207 | ;--------------------------------------- |
208 | ; unscale the window into a 32 bit value |
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209 | |||
2390 | hidnplayr | 210 | movzx eax, [edx + TCP_header.Window] |
211 | push ecx |
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212 | mov cl, [ebx + TCP_SOCKET.SND_SCALE] |
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213 | shl eax, cl |
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214 | mov dword [edx + TCP_header.Window], eax ; word after window is checksum, we dont need checksum anymore |
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215 | pop ecx |
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1733 | hidnplayr | 216 | |
2930 | hidnplayr | 217 | ;--------------------------------------- |
218 | ; Are we accepting incoming connections? |
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1733 | hidnplayr | 219 | |
2390 | hidnplayr | 220 | test [ebx + SOCKET.options], SO_ACCEPTCON |
2954 | hidnplayr | 221 | jz .no_accept |
1733 | hidnplayr | 222 | |
2954 | hidnplayr | 223 | DEBUGF 1,"TCP_input: Accepting new connection\n" |
224 | |||
225 | pusha |
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226 | lea ecx, [ebx + SOCKET.mutex] |
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227 | call mutex_unlock |
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228 | popa |
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229 | |||
230 | push ecx edx esi edi ;;; |
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231 | call SOCKET_fork |
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232 | pop edi esi edx ecx |
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233 | |||
234 | test eax, eax |
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235 | jz .drop_no_socket |
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236 | |||
237 | mov ebx, eax |
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238 | |||
239 | mov [ebx + TCP_SOCKET.temp_bits], TCP_BIT_DROPSOCKET ;;; FIXME: should we take over bits from previous socket? |
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240 | |||
241 | push dword [edi + 4] ; Ipv4 destination addres |
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242 | pop [ebx + IP_SOCKET.LocalIP] |
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243 | |||
244 | push [edx + TCP_header.DestinationPort] |
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245 | pop [ebx + TCP_SOCKET.LocalPort] |
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246 | |||
247 | mov [ebx + TCP_SOCKET.t_state], TCPS_LISTEN |
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248 | .no_accept: |
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249 | |||
250 | |||
1733 | hidnplayr | 251 | ;------------------------------------- |
252 | ; Reset idle timer and keepalive timer |
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253 | |||
2390 | hidnplayr | 254 | mov [ebx + TCP_SOCKET.t_idle], 0 |
3143 | hidnplayr | 255 | mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_idle |
1733 | hidnplayr | 256 | |
257 | ;-------------------- |
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258 | ; Process TCP options |
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259 | |||
3275 | hidnplayr | 260 | push ecx |
2954 | hidnplayr | 261 | |
262 | movzx ecx, [edx + TCP_header.DataOffset] |
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263 | cmp ecx, sizeof.TCP_header ; Does header contain any options? |
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2390 | hidnplayr | 264 | je .no_options |
1733 | hidnplayr | 265 | |
2891 | hidnplayr | 266 | DEBUGF 1,"TCP_input: Segment has options\n" |
1733 | hidnplayr | 267 | |
2954 | hidnplayr | 268 | ;;; FIXME: for LISTEN, options should be called after we determined route, we need it for MSS |
269 | ;;; cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN ; no options when in listen state |
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270 | ;;; jz .not_uni_xfer ; also no header prediction |
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1733 | hidnplayr | 271 | |
2954 | hidnplayr | 272 | add ecx, edx |
2390 | hidnplayr | 273 | lea esi, [edx + sizeof.TCP_header] |
1733 | hidnplayr | 274 | |
275 | .opt_loop: |
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2954 | hidnplayr | 276 | cmp esi, ecx ; are we scanning outside of header? |
2390 | hidnplayr | 277 | jae .no_options |
2954 | hidnplayr | 278 | lodsb |
279 | cmp al, TCP_OPT_EOL ; end of option list? |
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280 | je .no_options |
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281 | cmp al, TCP_OPT_NOP |
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282 | je .opt_loop |
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283 | cmp al, TCP_OPT_MAXSEG |
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2390 | hidnplayr | 284 | je .opt_maxseg |
2954 | hidnplayr | 285 | cmp al, TCP_OPT_WINDOW |
2390 | hidnplayr | 286 | je .opt_window |
2954 | hidnplayr | 287 | cmp al, TCP_OPT_SACK_PERMIT |
288 | je .opt_sack_permit |
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289 | ; cmp al, TCP_OPT_SACK |
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290 | ; je .opt_sack |
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291 | cmp al, TCP_OPT_TIMESTAMP |
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2390 | hidnplayr | 292 | je .opt_timestamp |
2954 | hidnplayr | 293 | DEBUGF 1,"TCP_input: unknown option:%u\n", al |
2937 | hidnplayr | 294 | jmp .no_options ; If we reach here, some unknown options were received, skip them all! |
1733 | hidnplayr | 295 | |
296 | .opt_maxseg: |
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2954 | hidnplayr | 297 | lodsb |
298 | cmp al, 4 |
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2937 | hidnplayr | 299 | jne .no_options ; error occured, ignore all options! |
1733 | hidnplayr | 300 | |
2390 | hidnplayr | 301 | test [edx + TCP_header.Flags], TH_SYN |
302 | jz @f |
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1733 | hidnplayr | 303 | |
2954 | hidnplayr | 304 | lodsw |
2390 | hidnplayr | 305 | rol ax, 8 |
2891 | hidnplayr | 306 | DEBUGF 1,"TCP_input: Maxseg=%u\n", ax |
3144 | hidnplayr | 307 | call TCP_mss |
1733 | hidnplayr | 308 | @@: |
2390 | hidnplayr | 309 | jmp .opt_loop |
1733 | hidnplayr | 310 | |
311 | |||
312 | .opt_window: |
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2954 | hidnplayr | 313 | lodsb |
314 | cmp al, 3 |
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2390 | hidnplayr | 315 | jne .no_options |
1733 | hidnplayr | 316 | |
2390 | hidnplayr | 317 | test [edx + TCP_header.Flags], TH_SYN |
318 | jz @f |
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1733 | hidnplayr | 319 | |
2954 | hidnplayr | 320 | DEBUGF 1,"TCP_input: Got window scale option\n" |
321 | or [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE |
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1733 | hidnplayr | 322 | |
2954 | hidnplayr | 323 | lodsb |
324 | mov [ebx + TCP_SOCKET.SND_SCALE], al |
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325 | ;;;;; TODO |
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326 | |||
1733 | hidnplayr | 327 | @@: |
2390 | hidnplayr | 328 | jmp .opt_loop |
1733 | hidnplayr | 329 | |
330 | |||
2954 | hidnplayr | 331 | .opt_sack_permit: |
332 | lodsb |
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333 | cmp al, 2 |
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334 | jne .no_options |
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335 | |||
336 | test [edx + TCP_header.Flags], TH_SYN |
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337 | jz @f |
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338 | |||
339 | DEBUGF 1,"TCP_input: Selective Acknowledgement permitted\n" |
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340 | or [ebx + TCP_SOCKET.t_flags], TF_SACK_PERMIT |
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341 | |||
342 | @@: |
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343 | jmp .opt_loop |
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344 | |||
345 | |||
1733 | hidnplayr | 346 | .opt_timestamp: |
2954 | hidnplayr | 347 | lodsb |
348 | cmp al, 10 ; length must be 10 |
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2390 | hidnplayr | 349 | jne .no_options |
1733 | hidnplayr | 350 | |
2891 | hidnplayr | 351 | DEBUGF 1,"TCP_input: Got timestamp option\n" |
1733 | hidnplayr | 352 | |
2954 | hidnplayr | 353 | test [edx + TCP_header.Flags], TH_SYN |
354 | jz @f |
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355 | or [ebx + TCP_SOCKET.t_flags], TF_RCVD_TSTMP |
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356 | @@: |
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357 | |||
358 | lodsd |
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359 | mov [ebx + TCP_SOCKET.ts_val], eax |
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360 | lodsd ; timestamp echo reply |
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361 | mov [ebx + TCP_SOCKET.ts_ecr], eax |
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2937 | hidnplayr | 362 | or [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
2930 | hidnplayr | 363 | |
2946 | hidnplayr | 364 | ; Since we have a timestamp, lets do the paws test right away! |
365 | |||
366 | test [edx + TCP_header.Flags], TH_RST |
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367 | jnz .no_paws |
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368 | |||
369 | mov eax, [ebx + TCP_SOCKET.ts_recent] |
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370 | test eax, eax |
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371 | jz .no_paws |
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372 | cmp eax, [ebx + TCP_SOCKET.ts_val] |
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373 | jge .no_paws |
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374 | |||
375 | DEBUGF 1,"TCP_input: PAWS: detected an old segment\n" |
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376 | |||
3251 | hidnplayr | 377 | mov eax, [esp+4+4] ; tcp_now |
2946 | hidnplayr | 378 | sub eax, [ebx + TCP_SOCKET.ts_recent_age] |
3252 | hidnplayr | 379 | |
380 | pop ecx |
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2946 | hidnplayr | 381 | cmp eax, TCP_PAWS_IDLE |
2947 | hidnplayr | 382 | jle .drop_after_ack ; TODO: update stats |
3252 | hidnplayr | 383 | push ecx |
2946 | hidnplayr | 384 | |
385 | mov [ebx + TCP_SOCKET.ts_recent], 0 ; timestamp was invalid, fix it. |
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386 | .no_paws: |
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2390 | hidnplayr | 387 | jmp .opt_loop |
1733 | hidnplayr | 388 | |
389 | .no_options: |
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390 | |||
3275 | hidnplayr | 391 | pop ecx |
2954 | hidnplayr | 392 | |
1733 | hidnplayr | 393 | ;----------------------------------------------------------------------- |
394 | ; Time to do some header prediction (Original Principle by Van Jacobson) |
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395 | |||
396 | ; There are two common cases for an uni-directional data transfer. |
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397 | ; |
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398 | ; General rule: the packets has no control flags, is in-sequence, |
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399 | ; window width didnt change and we're not retransmitting. |
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400 | ; |
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401 | ; Second rules: |
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402 | ; - If the length is 0 and the ACK moved forward, we're the sender side of the transfer. |
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403 | ; 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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404 | ; |
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405 | ; - If the length is not 0 and the ACK didn't move, we're the receiver side of the transfer. |
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406 | ; 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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407 | |||
2390 | hidnplayr | 408 | cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
409 | jnz .not_uni_xfer |
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1733 | hidnplayr | 410 | |
2390 | hidnplayr | 411 | test [edx + TCP_header.Flags], TH_SYN + TH_FIN + TH_RST + TH_URG |
412 | jnz .not_uni_xfer |
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1733 | hidnplayr | 413 | |
2390 | hidnplayr | 414 | test [edx + TCP_header.Flags], TH_ACK |
415 | jz .not_uni_xfer |
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1733 | hidnplayr | 416 | |
2390 | hidnplayr | 417 | mov eax, [edx + TCP_header.SequenceNumber] |
418 | cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
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419 | jne .not_uni_xfer |
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1733 | hidnplayr | 420 | |
2390 | hidnplayr | 421 | mov eax, dword [edx + TCP_header.Window] |
422 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
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423 | jne .not_uni_xfer |
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1733 | hidnplayr | 424 | |
2390 | hidnplayr | 425 | mov eax, [ebx + TCP_SOCKET.SND_NXT] |
426 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
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427 | jne .not_uni_xfer |
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1733 | hidnplayr | 428 | |
429 | ;--------------------------------------- |
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430 | ; check if we are sender in the uni-xfer |
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431 | |||
432 | ; If the following 4 conditions are all true, this segment is a pure ACK. |
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433 | ; |
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434 | ; - The segment contains no data. |
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2390 | hidnplayr | 435 | test ecx, ecx |
436 | jnz .not_sender |
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1733 | hidnplayr | 437 | |
438 | ; - The congestion window is greater than or equal to the current send window. |
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439 | ; 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 | 440 | mov eax, [ebx + TCP_SOCKET.SND_CWND] |
441 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
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442 | jb .not_uni_xfer |
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1733 | hidnplayr | 443 | |
444 | ; - The acknowledgment field in the segment is less than or equal to the maximum sequence number sent. |
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2390 | hidnplayr | 445 | mov eax, [edx + TCP_header.AckNumber] |
446 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
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447 | ja .not_uni_xfer |
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1733 | hidnplayr | 448 | |
449 | ; - The acknowledgment field in the segment is greater than the largest unacknowledged sequence number. |
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2390 | hidnplayr | 450 | sub eax, [ebx + TCP_SOCKET.SND_UNA] |
451 | jbe .not_uni_xfer |
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1733 | hidnplayr | 452 | |
2891 | hidnplayr | 453 | DEBUGF 1,"TCP_input: Header prediction: we are sender\n" |
1733 | hidnplayr | 454 | |
455 | ;--------------------------------- |
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456 | ; Packet is a pure ACK, process it |
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457 | |||
458 | ; Delete acknowledged bytes from send buffer |
||
2390 | hidnplayr | 459 | pusha |
460 | mov ecx, eax |
||
461 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
462 | call SOCKET_ring_free |
||
463 | popa |
||
1733 | hidnplayr | 464 | |
2930 | hidnplayr | 465 | ; Update RTT estimators |
466 | |||
2937 | hidnplayr | 467 | test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
468 | jz .no_timestamp_rtt |
||
3251 | hidnplayr | 469 | mov eax, [esp + 4] ; timestamp when this segment was received |
2937 | hidnplayr | 470 | sub eax, [ebx + TCP_SOCKET.ts_ecr] |
471 | inc eax |
||
472 | call TCP_xmit_timer |
||
473 | jmp .rtt_done |
||
2930 | hidnplayr | 474 | |
2937 | hidnplayr | 475 | .no_timestamp_rtt: |
476 | cmp [ebx + TCP_SOCKET.t_rtt], 0 |
||
477 | je .rtt_done |
||
478 | mov eax, [edx + TCP_header.AckNumber] |
||
479 | cmp eax, [ebx + TCP_SOCKET.t_rtseq] |
||
480 | jbe .rtt_done |
||
481 | mov eax, [ebx + TCP_SOCKET.t_rtt] |
||
482 | call TCP_xmit_timer |
||
2930 | hidnplayr | 483 | |
2937 | hidnplayr | 484 | .rtt_done: |
485 | |||
1733 | hidnplayr | 486 | ; update window pointers |
2390 | hidnplayr | 487 | mov eax, [edx + TCP_header.AckNumber] |
488 | mov [ebx + TCP_SOCKET.SND_UNA], eax |
||
1733 | hidnplayr | 489 | |
490 | ; Stop retransmit timer |
||
2390 | hidnplayr | 491 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 |
1733 | hidnplayr | 492 | |
3275 | hidnplayr | 493 | ; Unlock the socket |
2402 | hidnplayr | 494 | pusha |
495 | lea ecx, [ebx + SOCKET.mutex] |
||
496 | call mutex_unlock |
||
497 | popa |
||
498 | |||
3275 | hidnplayr | 499 | ; Awaken waiting processes |
2390 | hidnplayr | 500 | mov eax, ebx |
3257 | hidnplayr | 501 | call SOCKET_notify |
1733 | hidnplayr | 502 | |
1763 | hidnplayr | 503 | ; Generate more output |
2390 | hidnplayr | 504 | call TCP_output |
1733 | hidnplayr | 505 | |
2937 | hidnplayr | 506 | jmp .drop_no_socket |
1763 | hidnplayr | 507 | |
1733 | hidnplayr | 508 | ;------------------------------------------------- |
509 | ; maybe we are the receiver in the uni-xfer then.. |
||
510 | |||
511 | .not_sender: |
||
512 | ; - The amount of data in the segment is greater than 0 (data count is in ecx) |
||
513 | |||
514 | ; - The acknowledgment field equals the largest unacknowledged sequence number. This means no data is acknowledged by this segment. |
||
2390 | hidnplayr | 515 | mov eax, [edx + TCP_header.AckNumber] |
516 | cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
||
517 | jne .not_uni_xfer |
||
1733 | hidnplayr | 518 | |
519 | ; - The reassembly list of out-of-order segments for the connection is empty (seg_next equals tp). |
||
520 | |||
521 | ;;; TODO |
||
522 | |||
2930 | hidnplayr | 523 | ; jnz .not_uni_xfer |
1733 | hidnplayr | 524 | |
525 | ; Complete processing of received data |
||
526 | |||
2891 | hidnplayr | 527 | DEBUGF 1,"TCP_input: Header prediction: we are receiving %u bytes\n", ecx |
1733 | hidnplayr | 528 | |
2390 | hidnplayr | 529 | add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied |
1763 | hidnplayr | 530 | |
2390 | hidnplayr | 531 | movzx esi, [edx + TCP_header.DataOffset] |
532 | add esi, edx |
||
533 | lea eax, [ebx + STREAM_SOCKET.rcv] |
||
534 | call SOCKET_ring_write ; Add the data to the socket buffer |
||
1733 | hidnplayr | 535 | |
2390 | hidnplayr | 536 | mov eax, ebx |
3257 | hidnplayr | 537 | call SOCKET_notify |
1733 | hidnplayr | 538 | |
2390 | hidnplayr | 539 | or [ebx + TCP_SOCKET.t_flags], TF_DELACK ; Set delayed ack flag |
1733 | hidnplayr | 540 | |
2390 | hidnplayr | 541 | jmp .drop |
1733 | hidnplayr | 542 | |
543 | ;-------------------------------------------------- |
||
544 | ; Header prediction failed, do it the slow way |
||
545 | |||
546 | .not_uni_xfer: |
||
547 | |||
2891 | hidnplayr | 548 | DEBUGF 1,"TCP_input: Header prediction failed\n" |
1733 | hidnplayr | 549 | |
550 | ; Calculate receive window size |
||
551 | |||
2942 | hidnplayr | 552 | push edx |
2937 | hidnplayr | 553 | mov eax, SOCKETBUFFSIZE |
554 | sub eax, [ebx + STREAM_SOCKET.rcv.size] |
||
555 | mov edx, [ebx + TCP_SOCKET.RCV_ADV] |
||
556 | sub edx, [ebx + TCP_SOCKET.RCV_NXT] |
||
557 | cmp eax, edx |
||
2942 | hidnplayr | 558 | jg @f |
2937 | hidnplayr | 559 | mov eax, edx |
560 | @@: |
||
2957 | hidnplayr | 561 | DEBUGF 1,"Receive window size=%d\n", eax |
562 | mov [ebx + TCP_SOCKET.RCV_WND], eax |
||
2942 | hidnplayr | 563 | pop edx |
1733 | hidnplayr | 564 | |
3275 | hidnplayr | 565 | ; If we are in listen or syn_sent state, go to that specific code right away |
2937 | hidnplayr | 566 | |
2390 | hidnplayr | 567 | cmp [ebx + TCP_SOCKET.t_state], TCPS_LISTEN |
568 | je .LISTEN |
||
1733 | hidnplayr | 569 | |
2390 | hidnplayr | 570 | cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_SENT |
571 | je .SYN_SENT |
||
1733 | hidnplayr | 572 | |
573 | ;---------------------------- |
||
574 | ; trim any data not in window |
||
575 | |||
3406 | hidnplayr | 576 | ; check for duplicate data at beginning of segment (635) |
1733 | hidnplayr | 577 | |
2390 | hidnplayr | 578 | mov eax, [ebx + TCP_SOCKET.RCV_NXT] |
579 | sub eax, [edx + TCP_header.SequenceNumber] |
||
2942 | hidnplayr | 580 | jle .no_duplicate |
1733 | hidnplayr | 581 | |
2891 | hidnplayr | 582 | DEBUGF 1,"TCP_input: %u bytes duplicate data!\n", eax |
1763 | hidnplayr | 583 | |
2390 | hidnplayr | 584 | test [edx + TCP_header.Flags], TH_SYN |
585 | jz .no_dup_syn |
||
1733 | hidnplayr | 586 | |
2942 | hidnplayr | 587 | DEBUGF 1,"TCP_input: got duplicate syn\n" |
1733 | hidnplayr | 588 | |
2390 | hidnplayr | 589 | and [edx + TCP_header.Flags], not (TH_SYN) |
590 | inc [edx + TCP_header.SequenceNumber] |
||
1733 | hidnplayr | 591 | |
2390 | hidnplayr | 592 | cmp [edx + TCP_header.UrgentPointer], 1 |
593 | jbe @f |
||
594 | dec [edx + TCP_header.UrgentPointer] |
||
595 | jmp .dup_syn |
||
1733 | hidnplayr | 596 | @@: |
2390 | hidnplayr | 597 | and [edx + TCP_header.Flags], not (TH_URG) |
1838 | hidnplayr | 598 | .dup_syn: |
2390 | hidnplayr | 599 | dec eax |
1763 | hidnplayr | 600 | .no_dup_syn: |
1733 | hidnplayr | 601 | |
3406 | hidnplayr | 602 | ; Check for entire duplicate segment (646) |
2937 | hidnplayr | 603 | cmp eax, ecx ; eax holds number of bytes to drop, ecx is data size |
604 | jb .duplicate |
||
605 | jnz @f |
||
2390 | hidnplayr | 606 | test [edx + TCP_header.Flags], TH_FIN |
2937 | hidnplayr | 607 | jnz .duplicate |
608 | @@: |
||
1733 | hidnplayr | 609 | |
2937 | hidnplayr | 610 | ; Any valid FIN must be to the left of the window. |
611 | ; At this point the FIN must be out of sequence or a duplicate, drop it |
||
2390 | hidnplayr | 612 | and [edx + TCP_header.Flags], not TH_FIN |
2937 | hidnplayr | 613 | |
614 | ; send an ACK and resynchronize and drop any data. |
||
615 | ; But keep on processing for RST or ACK |
||
3406 | hidnplayr | 616 | DEBUGF 1, "616\n" |
2390 | hidnplayr | 617 | or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
2937 | hidnplayr | 618 | mov eax, ecx |
619 | ;TODO: update stats |
||
1733 | hidnplayr | 620 | |
621 | ;----------------------------------------------- |
||
622 | ; Remove duplicate data and update urgent offset |
||
623 | |||
2937 | hidnplayr | 624 | .duplicate: |
625 | ;;; TODO: 677 |
||
2390 | hidnplayr | 626 | add [edx + TCP_header.SequenceNumber], eax |
2937 | hidnplayr | 627 | sub ecx, eax |
1733 | hidnplayr | 628 | |
2390 | hidnplayr | 629 | sub [edx + TCP_header.UrgentPointer], ax |
2942 | hidnplayr | 630 | jg @f |
2390 | hidnplayr | 631 | and [edx + TCP_header.Flags], not (TH_URG) |
632 | mov [edx + TCP_header.UrgentPointer], 0 |
||
1733 | hidnplayr | 633 | @@: |
634 | |||
635 | ;-------------------------------------------------- |
||
3406 | hidnplayr | 636 | ; Handle data that arrives after process terminates (687) |
1733 | hidnplayr | 637 | |
2937 | hidnplayr | 638 | .no_duplicate: |
2390 | hidnplayr | 639 | cmp [ebx + SOCKET.PID], 0 |
2937 | hidnplayr | 640 | jne .not_terminated |
2390 | hidnplayr | 641 | cmp [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT |
2937 | hidnplayr | 642 | jbe .not_terminated |
2390 | hidnplayr | 643 | test ecx, ecx |
2937 | hidnplayr | 644 | jz .not_terminated |
1733 | hidnplayr | 645 | |
2937 | hidnplayr | 646 | mov eax, ebx |
647 | call TCP_close |
||
648 | ;;;TODO: update stats |
||
3275 | hidnplayr | 649 | jmp .respond_seg_reset |
1733 | hidnplayr | 650 | |
651 | ;---------------------------------------- |
||
2937 | hidnplayr | 652 | ; Remove data beyond right edge of window (700-736) |
1733 | hidnplayr | 653 | |
2937 | hidnplayr | 654 | .not_terminated: |
2390 | hidnplayr | 655 | mov eax, [edx + TCP_header.SequenceNumber] |
656 | add eax, ecx |
||
657 | sub eax, [ebx + TCP_SOCKET.RCV_NXT] |
||
2957 | hidnplayr | 658 | sub eax, [ebx + TCP_SOCKET.RCV_WND] ; eax now holds the number of bytes to drop |
2942 | hidnplayr | 659 | jle .no_excess_data |
1733 | hidnplayr | 660 | |
2942 | hidnplayr | 661 | DEBUGF 1,"%d bytes beyond right edge of window\n", eax |
662 | |||
1733 | hidnplayr | 663 | ;;; TODO: update stats |
2390 | hidnplayr | 664 | cmp eax, ecx |
2942 | hidnplayr | 665 | jl .dont_drop_all |
2937 | hidnplayr | 666 | ; If a new connection request is received while in TIME_WAIT, drop the old connection and start over, |
667 | ; if the sequence numbers are above the previous ones |
||
1733 | hidnplayr | 668 | |
2937 | hidnplayr | 669 | test [edx + TCP_header.Flags], TH_SYN |
670 | jz .no_new_request |
||
671 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
||
672 | jne .no_new_request |
||
2942 | hidnplayr | 673 | ; mov edx, [ebx + TCP_SOCKET.RCV_NXT] |
674 | ; cmp edx, [edx + TCP_header.SequenceNumber] |
||
675 | ; add edx, 64000 ; TCP_ISSINCR FIXME |
||
2937 | hidnplayr | 676 | mov eax, ebx |
677 | call TCP_close |
||
678 | jmp .findpcb ; FIXME: skip code for unscaling window, ... |
||
679 | .no_new_request: |
||
1733 | hidnplayr | 680 | |
2937 | hidnplayr | 681 | ; If window is closed can only take segments at window edge, and have to drop data and PUSH from |
682 | ; incoming segments. Continue processing, but remember to ACK. Otherwise drop segment and ACK |
||
683 | |||
684 | cmp [ebx + TCP_SOCKET.RCV_WND], 0 |
||
685 | jne .drop_after_ack |
||
686 | mov eax, [edx + TCP_header.SequenceNumber] |
||
687 | cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
||
688 | jne .drop_after_ack |
||
689 | |||
3406 | hidnplayr | 690 | DEBUGF 1, "690\n" |
2937 | hidnplayr | 691 | or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
692 | ;;; TODO: update stats |
||
693 | jmp .no_excess_data |
||
1733 | hidnplayr | 694 | .dont_drop_all: |
2937 | hidnplayr | 695 | ;;; TODO: update stats |
696 | ;;; TODO: 733 |
||
2957 | hidnplayr | 697 | |
2937 | hidnplayr | 698 | sub ecx, eax |
699 | and [ebx + TCP_SOCKET.t_flags], not (TH_PUSH or TH_FIN) |
||
1733 | hidnplayr | 700 | .no_excess_data: |
701 | |||
702 | ;----------------- |
||
2948 | hidnplayr | 703 | ; Record timestamp (737-746) |
1733 | hidnplayr | 704 | |
2937 | hidnplayr | 705 | ; If last ACK falls within this segments sequence numbers, record its timestamp |
706 | test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
||
707 | jz .no_timestamp |
||
708 | mov eax, [ebx + TCP_SOCKET.last_ack_sent] |
||
709 | sub eax, [edx + TCP_header.SequenceNumber] |
||
710 | jb .no_timestamp |
||
711 | test [ebx + TCP_header.Flags], TH_SYN or TH_FIN ; syn and fin occupy one byte |
||
712 | jz @f |
||
713 | dec eax |
||
714 | @@: |
||
715 | sub eax, ecx |
||
716 | jae .no_timestamp |
||
1733 | hidnplayr | 717 | |
2948 | hidnplayr | 718 | DEBUGF 1,"Recording timestamp\n" |
719 | |||
3251 | hidnplayr | 720 | mov eax, [esp + 4] ; tcp_now |
2937 | hidnplayr | 721 | mov [ebx + TCP_SOCKET.ts_recent_age], eax |
722 | mov eax, [ebx + TCP_SOCKET.ts_val] |
||
723 | mov [ebx + TCP_SOCKET.ts_recent], eax |
||
724 | .no_timestamp: |
||
1733 | hidnplayr | 725 | |
726 | ;------------------ |
||
727 | ; Process RST flags |
||
728 | |||
2390 | hidnplayr | 729 | test [edx + TCP_header.Flags], TH_RST |
2891 | hidnplayr | 730 | jz .no_rst |
1733 | hidnplayr | 731 | |
2891 | hidnplayr | 732 | DEBUGF 1,"TCP_input: Got an RST flag\n" |
1733 | hidnplayr | 733 | |
2390 | hidnplayr | 734 | mov eax, [ebx + TCP_SOCKET.t_state] |
735 | shl eax, 2 |
||
736 | jmp dword [eax + .rst_sw_list] |
||
1733 | hidnplayr | 737 | |
738 | .rst_sw_list: |
||
2891 | hidnplayr | 739 | dd .no_rst ; TCPS_CLOSED |
740 | dd .no_rst ; TCPS_LISTEN |
||
741 | dd .no_rst ; TCPS_SYN_SENT |
||
742 | dd .econnrefused ; TCPS_SYN_RECEIVED |
||
743 | dd .econnreset ; TCPS_ESTABLISHED |
||
744 | dd .econnreset ; TCPS_CLOSE_WAIT |
||
745 | dd .econnreset ; TCPS_FIN_WAIT_1 |
||
746 | dd .rst_close ; TCPS_CLOSING |
||
747 | dd .rst_close ; TCPS_LAST_ACK |
||
748 | dd .econnreset ; TCPS_FIN_WAIT_2 |
||
749 | dd .rst_close ; TCPS_TIMED_WAIT |
||
1733 | hidnplayr | 750 | |
751 | .econnrefused: |
||
2891 | hidnplayr | 752 | DEBUGF 1,"TCP_input: Connection refused\n" |
1733 | hidnplayr | 753 | |
2390 | hidnplayr | 754 | mov [ebx + SOCKET.errorcode], ECONNREFUSED |
755 | jmp .close |
||
1733 | hidnplayr | 756 | |
757 | .econnreset: |
||
2891 | hidnplayr | 758 | DEBUGF 1,"TCP_input: Connection reset\n" |
1733 | hidnplayr | 759 | |
2390 | hidnplayr | 760 | mov [ebx + SOCKET.errorcode], ECONNRESET |
1733 | hidnplayr | 761 | |
2882 | hidnplayr | 762 | .close: |
2891 | hidnplayr | 763 | DEBUGF 1,"TCP_input: Closing connection\n" |
1733 | hidnplayr | 764 | |
2390 | hidnplayr | 765 | mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSED |
2937 | hidnplayr | 766 | ;;; TODO: update stats (tcp drops) |
2390 | hidnplayr | 767 | mov eax, ebx |
768 | call TCP_close |
||
3270 | hidnplayr | 769 | jmp .drop_no_socket |
1733 | hidnplayr | 770 | |
771 | .rst_close: |
||
2891 | hidnplayr | 772 | DEBUGF 1,"TCP_input: Closing with reset\n" |
1733 | hidnplayr | 773 | |
2390 | hidnplayr | 774 | mov eax, ebx |
775 | call TCP_close |
||
3270 | hidnplayr | 776 | jmp .drop_no_socket |
1733 | hidnplayr | 777 | |
2891 | hidnplayr | 778 | .no_rst: |
1733 | hidnplayr | 779 | |
780 | ;-------------------------------------- |
||
781 | ; handle SYN-full and ACK-less segments |
||
782 | |||
2390 | hidnplayr | 783 | test [edx + TCP_header.Flags], TH_SYN |
2937 | hidnplayr | 784 | jz .not_syn_full |
1733 | hidnplayr | 785 | |
2390 | hidnplayr | 786 | mov eax, ebx |
787 | mov ebx, ECONNRESET |
||
788 | call TCP_drop |
||
789 | jmp .drop_with_reset |
||
2937 | hidnplayr | 790 | .not_syn_full: |
1733 | hidnplayr | 791 | |
792 | ;--------------- |
||
793 | ; ACK processing |
||
794 | |||
2891 | hidnplayr | 795 | test [edx + TCP_header.Flags], TH_ACK |
796 | jz .drop |
||
797 | |||
2390 | hidnplayr | 798 | cmp [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
2937 | hidnplayr | 799 | jb .ack_processed ; states: closed, listen, syn_sent |
800 | ja .no_syn_rcv ; established, fin_wait_1, fin_wait_2, close_wait, closing, last_ack, time_wait |
||
1733 | hidnplayr | 801 | |
2891 | hidnplayr | 802 | DEBUGF 1,"TCP_input: state=syn_received\n" |
1733 | hidnplayr | 803 | |
2390 | hidnplayr | 804 | mov eax, [edx + TCP_header.AckNumber] |
805 | cmp [ebx + TCP_SOCKET.SND_UNA], eax |
||
806 | ja .drop_with_reset |
||
807 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
||
808 | ja .drop_with_reset |
||
1733 | hidnplayr | 809 | |
2309 | hidnplayr | 810 | ;;; TODO: update stats |
811 | |||
2390 | hidnplayr | 812 | mov eax, ebx |
813 | call SOCKET_is_connected |
||
814 | mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
||
1831 | hidnplayr | 815 | |
816 | ; Do window scaling? |
||
817 | |||
2390 | hidnplayr | 818 | test [ebx + TCP_SOCKET.t_flags], TF_RCVD_SCALE |
819 | jz @f |
||
820 | test [ebx + TCP_SOCKET.t_flags], TF_REQ_SCALE |
||
821 | jz @f |
||
1831 | hidnplayr | 822 | |
2390 | hidnplayr | 823 | push word [ebx + TCP_SOCKET.requested_s_scale] ; Set send and receive scale factors to the received values |
824 | pop word [ebx + TCP_SOCKET.SND_SCALE] |
||
1831 | hidnplayr | 825 | @@: |
826 | |||
2891 | hidnplayr | 827 | ;;; TODO: call TCP_reassemble |
1831 | hidnplayr | 828 | |
2390 | hidnplayr | 829 | mov eax, [edx + TCP_header.SequenceNumber] |
830 | dec eax |
||
831 | mov [ebx + TCP_SOCKET.SND_WL1], eax |
||
1831 | hidnplayr | 832 | |
1733 | hidnplayr | 833 | .no_syn_rcv: |
834 | |||
2937 | hidnplayr | 835 | ;------------------------- |
836 | ; check for duplicate ACKs |
||
1733 | hidnplayr | 837 | |
2390 | hidnplayr | 838 | mov eax, [edx + TCP_header.AckNumber] |
839 | cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
||
840 | ja .not_dup_ack |
||
1733 | hidnplayr | 841 | |
2390 | hidnplayr | 842 | test ecx, ecx |
843 | jnz .reset_dupacks |
||
1733 | hidnplayr | 844 | |
2390 | hidnplayr | 845 | mov eax, dword [edx + TCP_header.Window] |
846 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
||
847 | jne .reset_dupacks |
||
1733 | hidnplayr | 848 | |
2891 | hidnplayr | 849 | DEBUGF 1,"TCP_input: Processing duplicate ACK\n" |
1733 | hidnplayr | 850 | |
2948 | hidnplayr | 851 | ; If we have outstanding data, other than a window probe, this is a completely duplicate ACK |
2937 | hidnplayr | 852 | ; (window info didnt change) The ACK is the biggest we've seen and we've seen exactly our rexmt threshold of them, |
853 | ; assume a packet has been dropped and retransmit it. Kludge snd_nxt & the congestion window so we send only this one packet. |
||
1733 | hidnplayr | 854 | |
2937 | hidnplayr | 855 | cmp [ebx + TCP_SOCKET.timer_retransmission], 0 ;;;; FIXME |
856 | jg @f |
||
857 | |||
2390 | hidnplayr | 858 | mov eax, [edx + TCP_header.AckNumber] |
859 | cmp eax, [ebx + TCP_SOCKET.SND_UNA] |
||
860 | je .dup_ack |
||
1763 | hidnplayr | 861 | |
862 | @@: |
||
2390 | hidnplayr | 863 | mov [ebx + TCP_SOCKET.t_dupacks], 0 |
864 | jmp .not_dup_ack |
||
1763 | hidnplayr | 865 | |
866 | .dup_ack: |
||
2390 | hidnplayr | 867 | inc [ebx + TCP_SOCKET.t_dupacks] |
868 | cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh |
||
869 | jne .no_re_xmit |
||
1763 | hidnplayr | 870 | |
2390 | hidnplayr | 871 | push [ebx + TCP_SOCKET.SND_NXT] ; >>>> |
1763 | hidnplayr | 872 | |
2390 | hidnplayr | 873 | mov eax, [ebx + TCP_SOCKET.SND_WND] |
874 | cmp eax, [ebx + TCP_SOCKET.SND_CWND] |
||
2866 | hidnplayr | 875 | cmova eax, [ebx + TCP_SOCKET.SND_CWND] |
2390 | hidnplayr | 876 | shr eax, 1 |
877 | push edx |
||
878 | xor edx, edx |
||
879 | div [ebx + TCP_SOCKET.t_maxseg] |
||
880 | cmp eax, 2 |
||
2937 | hidnplayr | 881 | ja @f |
882 | xor eax, eax |
||
883 | mov al, 2 |
||
1763 | hidnplayr | 884 | @@: |
2390 | hidnplayr | 885 | mul [ebx + TCP_SOCKET.t_maxseg] |
886 | pop edx |
||
887 | mov [ebx + TCP_SOCKET.SND_SSTHRESH], eax |
||
1763 | hidnplayr | 888 | |
2390 | hidnplayr | 889 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; turn off retransmission timer |
890 | mov [ebx + TCP_SOCKET.t_rtt], 0 |
||
891 | mov eax, [edx + TCP_header.AckNumber] |
||
892 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
893 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
||
894 | mov [ebx + TCP_SOCKET.SND_CWND], eax |
||
1763 | hidnplayr | 895 | |
3275 | hidnplayr | 896 | ; Unlock the socket |
897 | push ebx |
||
898 | lea ecx, [ebx + SOCKET.mutex] |
||
899 | call mutex_unlock |
||
1763 | hidnplayr | 900 | |
3275 | hidnplayr | 901 | ; retransmit missing segment |
902 | mov eax, [esp] |
||
903 | call TCP_output |
||
904 | |||
905 | ; Lock the socket again |
||
906 | mov ecx, [esp] |
||
907 | add ecx, SOCKET.mutex |
||
908 | call mutex_lock |
||
909 | pop ebx |
||
910 | |||
911 | ; Continue processing |
||
2390 | hidnplayr | 912 | xor edx, edx |
913 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
||
914 | mul [ebx + TCP_SOCKET.t_dupacks] |
||
915 | add eax, [ebx + TCP_SOCKET.SND_SSTHRESH] |
||
916 | mov [ebx + TCP_SOCKET.SND_CWND], eax |
||
1763 | hidnplayr | 917 | |
2390 | hidnplayr | 918 | pop eax ; <<<< |
919 | cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
||
920 | jb @f |
||
921 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1763 | hidnplayr | 922 | @@: |
923 | |||
2390 | hidnplayr | 924 | jmp .drop |
1733 | hidnplayr | 925 | |
926 | |||
1763 | hidnplayr | 927 | .no_re_xmit: |
2390 | hidnplayr | 928 | jbe .not_dup_ack |
1733 | hidnplayr | 929 | |
2891 | hidnplayr | 930 | DEBUGF 1,"TCP_input: Increasing congestion window\n" |
1733 | hidnplayr | 931 | |
2390 | hidnplayr | 932 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
933 | add [ebx + TCP_SOCKET.SND_CWND], eax |
||
1733 | hidnplayr | 934 | |
3275 | hidnplayr | 935 | ; Unlock the socket |
936 | push ebx |
||
937 | lea ecx, [ebx + SOCKET.mutex] |
||
938 | call mutex_unlock |
||
939 | |||
940 | ; retransmit missing segment |
||
941 | mov eax, [esp] |
||
2390 | hidnplayr | 942 | call TCP_output |
1733 | hidnplayr | 943 | |
3275 | hidnplayr | 944 | ; Lock the socket again |
945 | mov ecx, [esp] |
||
946 | add ecx, SOCKET.mutex |
||
947 | call mutex_lock |
||
948 | pop ebx |
||
949 | |||
2390 | hidnplayr | 950 | jmp .drop |
1733 | hidnplayr | 951 | |
952 | |||
1763 | hidnplayr | 953 | .not_dup_ack: |
954 | |||
1733 | hidnplayr | 955 | ;------------------------------------------------- |
956 | ; If the congestion window was inflated to account |
||
957 | ; for the other side's cached packets, retract it |
||
958 | |||
2390 | hidnplayr | 959 | mov eax, [ebx + TCP_SOCKET.SND_SSTHRESH] |
960 | cmp eax, [ebx + TCP_SOCKET.SND_CWND] |
||
961 | ja @f |
||
962 | cmp [ebx + TCP_SOCKET.t_dupacks], TCP_re_xmit_thresh |
||
963 | jbe @f |
||
964 | mov [ebx + TCP_SOCKET.SND_CWND], eax |
||
1763 | hidnplayr | 965 | @@: |
1733 | hidnplayr | 966 | |
2390 | hidnplayr | 967 | mov [ebx + TCP_SOCKET.t_dupacks], 0 |
1733 | hidnplayr | 968 | |
2390 | hidnplayr | 969 | mov eax, [edx + TCP_header.AckNumber] |
970 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
||
971 | jbe @f |
||
1733 | hidnplayr | 972 | |
2390 | hidnplayr | 973 | ;;; TODO: update stats |
974 | jmp .drop_after_ack |
||
1733 | hidnplayr | 975 | |
1763 | hidnplayr | 976 | @@: |
1733 | hidnplayr | 977 | |
2390 | hidnplayr | 978 | mov edi, [edx + TCP_header.AckNumber] |
979 | sub edi, [ebx + TCP_SOCKET.SND_UNA] ; now we got the number of acked bytes in edi |
||
1733 | hidnplayr | 980 | |
2390 | hidnplayr | 981 | ;;; TODO: update stats |
1733 | hidnplayr | 982 | |
2891 | hidnplayr | 983 | DEBUGF 1,"TCP_input: acceptable ACK for %u bytes\n", edi |
1763 | hidnplayr | 984 | |
1733 | hidnplayr | 985 | ;------------------------------------------ |
2937 | hidnplayr | 986 | ; RTT measurements and retransmission timer (912-926) |
1733 | hidnplayr | 987 | |
2937 | hidnplayr | 988 | ; If we have a timestamp, update smoothed RTT |
1733 | hidnplayr | 989 | |
2937 | hidnplayr | 990 | test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_TIMESTAMP |
2948 | hidnplayr | 991 | jz .timestamp_not_present |
3251 | hidnplayr | 992 | mov eax, [esp+4] |
2937 | hidnplayr | 993 | sub eax, [ebx + TCP_SOCKET.ts_ecr] |
994 | inc eax |
||
995 | call TCP_xmit_timer |
||
996 | jmp .rtt_done_ |
||
1733 | hidnplayr | 997 | |
2937 | hidnplayr | 998 | ; If no timestamp but transmit timer is running and timed sequence number was acked, |
999 | ; update smoothed RTT. Since we now have an RTT measurement, cancel the timer backoff |
||
1000 | ; (Phil Karn's retransmit algo) |
||
1001 | ; Recompute the initial retransmit timer |
||
1002 | |||
1003 | .timestamp_not_present: |
||
1004 | mov eax, [edx + TCP_header.AckNumber] |
||
1005 | cmp eax, [ebx + TCP_SOCKET.t_rtseq] |
||
1006 | jbe .rtt_done_ |
||
1007 | mov eax, [ebx + TCP_SOCKET.t_rtt] |
||
1008 | test eax, eax |
||
1009 | jz .rtt_done_ |
||
1010 | call TCP_xmit_timer |
||
1011 | |||
1012 | .rtt_done_: |
||
1013 | |||
1014 | ; If all outstanding data is acked, stop retransmit timer and remember to restart (more output or persist) |
||
1015 | ; If there is more data to be acked, restart retransmit timer, using current (possible backed-off) value. |
||
1016 | |||
2390 | hidnplayr | 1017 | mov eax, [ebx + TCP_SOCKET.SND_MAX] |
1018 | cmp eax, [edx + TCP_header.AckNumber] |
||
2937 | hidnplayr | 1019 | jne .more_data |
1020 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 |
||
1021 | or [ebx + TCP_SOCKET.temp_bits], TCP_BIT_NEEDOUTPUT |
||
1022 | jmp .no_restart |
||
1023 | .more_data: |
||
1024 | cmp [ebx + TCP_SOCKET.timer_persist], 0 |
||
1025 | jne .no_restart |
||
2891 | hidnplayr | 1026 | |
2937 | hidnplayr | 1027 | mov eax, [ebx + TCP_SOCKET.t_rxtcur] |
2955 | hidnplayr | 1028 | mov [ebx + TCP_SOCKET.timer_retransmission], eax |
1733 | hidnplayr | 1029 | |
2937 | hidnplayr | 1030 | .no_restart: |
1031 | |||
1032 | |||
1733 | hidnplayr | 1033 | ;------------------------------------------- |
1034 | ; Open congestion window in response to ACKs |
||
1035 | |||
2390 | hidnplayr | 1036 | mov esi, [ebx + TCP_SOCKET.SND_CWND] |
1037 | mov eax, [ebx + TCP_SOCKET.t_maxseg] |
||
1733 | hidnplayr | 1038 | |
2390 | hidnplayr | 1039 | cmp esi, [ebx + TCP_SOCKET.SND_SSTHRESH] |
1040 | jbe @f |
||
1041 | push edx |
||
1042 | push eax |
||
1043 | mul eax |
||
1044 | div esi |
||
1045 | pop edx |
||
1046 | shr edx, 3 |
||
1047 | add eax, edx |
||
1048 | pop edx |
||
1763 | hidnplayr | 1049 | @@: |
1733 | hidnplayr | 1050 | |
2390 | hidnplayr | 1051 | add esi, eax |
1733 | hidnplayr | 1052 | |
2390 | hidnplayr | 1053 | push ecx |
1054 | mov cl, [ebx + TCP_SOCKET.SND_SCALE] |
||
1055 | mov eax, TCP_max_win |
||
1056 | shl eax, cl |
||
1057 | pop ecx |
||
1733 | hidnplayr | 1058 | |
2390 | hidnplayr | 1059 | cmp esi, eax |
2866 | hidnplayr | 1060 | cmova esi, eax |
2390 | hidnplayr | 1061 | mov [ebx + TCP_SOCKET.SND_CWND], esi |
1733 | hidnplayr | 1062 | |
2891 | hidnplayr | 1063 | ;------------------------------------------ |
1064 | ; Remove acknowledged data from send buffer |
||
1733 | hidnplayr | 1065 | |
2891 | hidnplayr | 1066 | cmp edi, [ebx + STREAM_SOCKET.snd.size] |
1067 | jbe .finiacked |
||
1733 | hidnplayr | 1068 | |
2891 | hidnplayr | 1069 | push ecx edx ebx |
1070 | mov ecx, [ebx + STREAM_SOCKET.snd.size] |
||
1071 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
1072 | sub [ebx + TCP_SOCKET.SND_WND], ecx |
||
1073 | call SOCKET_ring_free |
||
1074 | pop ebx edx ecx |
||
1733 | hidnplayr | 1075 | |
2891 | hidnplayr | 1076 | DEBUGF 1,"TCP_input: our FIN is acked\n" |
1077 | stc |
||
1763 | hidnplayr | 1078 | |
2891 | hidnplayr | 1079 | jmp .wakeup |
1763 | hidnplayr | 1080 | |
2891 | hidnplayr | 1081 | .finiacked: |
1763 | hidnplayr | 1082 | |
2390 | hidnplayr | 1083 | push ecx edx ebx |
1084 | mov ecx, edi |
||
1085 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
1086 | call SOCKET_ring_free |
||
1087 | pop ebx |
||
1088 | sub [ebx + TCP_SOCKET.SND_WND], ecx |
||
1089 | pop edx ecx |
||
1733 | hidnplayr | 1090 | |
2891 | hidnplayr | 1091 | DEBUGF 1,"TCP_input: our FIN is not acked\n" |
1092 | clc |
||
1093 | |||
1094 | ;---------------------------------------- |
||
1733 | hidnplayr | 1095 | ; Wake up process waiting on send buffer |
1096 | |||
2891 | hidnplayr | 1097 | .wakeup: |
1098 | |||
3275 | hidnplayr | 1099 | pushf ; Keep the flags (Carry flag) |
2390 | hidnplayr | 1100 | mov eax, ebx |
3257 | hidnplayr | 1101 | call SOCKET_notify |
1733 | hidnplayr | 1102 | |
1831 | hidnplayr | 1103 | ; Update TCPS |
1733 | hidnplayr | 1104 | |
2390 | hidnplayr | 1105 | mov eax, [edx + TCP_header.AckNumber] |
1106 | mov [ebx + TCP_SOCKET.SND_UNA], eax |
||
1107 | cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
||
1108 | jb @f |
||
1109 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1733 | hidnplayr | 1110 | @@: |
1111 | |||
2891 | hidnplayr | 1112 | popf |
1733 | hidnplayr | 1113 | |
1114 | ; General ACK handling complete |
||
1115 | ; Now do the state-specific ones |
||
3275 | hidnplayr | 1116 | ; Carry flag is set when our FIN is acked |
1733 | hidnplayr | 1117 | |
2390 | hidnplayr | 1118 | mov eax, [ebx + TCP_SOCKET.t_state] |
1119 | jmp dword [eax*4 + .ACK_sw_list] |
||
1733 | hidnplayr | 1120 | |
1121 | .ACK_sw_list: |
||
2891 | hidnplayr | 1122 | dd .ack_processed ; TCPS_CLOSED |
1123 | dd .ack_processed ; TCPS_LISTEN |
||
1124 | dd .ack_processed ; TCPS_SYN_SENT |
||
1125 | dd .ack_processed ; TCPS_SYN_RECEIVED |
||
1126 | dd .ack_processed ; TCPS_ESTABLISHED |
||
1127 | dd .ack_processed ; TCPS_CLOSE_WAIT |
||
1128 | dd .ack_fw1 ; TCPS_FIN_WAIT_1 |
||
1129 | dd .ack_c ; TCPS_CLOSING |
||
1130 | dd .ack_la ; TCPS_LAST_ACK |
||
1131 | dd .ack_processed ; TCPS_FIN_WAIT_2 |
||
1132 | dd .ack_tw ; TCPS_TIMED_WAIT |
||
1733 | hidnplayr | 1133 | |
1134 | |||
1772 | hidnplayr | 1135 | .ack_fw1: |
2891 | hidnplayr | 1136 | jnc .ack_processed |
1733 | hidnplayr | 1137 | |
2390 | hidnplayr | 1138 | test [ebx + SOCKET.state], SS_CANTRCVMORE |
1139 | jnz @f |
||
1140 | mov eax, ebx |
||
1141 | call SOCKET_is_disconnected |
||
2937 | hidnplayr | 1142 | mov [ebx + TCP_SOCKET.timer_timed_wait], TCP_time_max_idle |
1772 | hidnplayr | 1143 | @@: |
2390 | hidnplayr | 1144 | mov [ebx + TCP_SOCKET.t_state], TCPS_FIN_WAIT_2 |
1145 | jmp .ack_processed |
||
1733 | hidnplayr | 1146 | |
1772 | hidnplayr | 1147 | .ack_c: |
2891 | hidnplayr | 1148 | jnc .ack_processed |
1772 | hidnplayr | 1149 | |
2390 | hidnplayr | 1150 | mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1151 | mov eax, ebx |
||
1152 | call TCP_cancel_timers |
||
1153 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
||
1154 | mov eax, ebx |
||
1155 | call SOCKET_is_disconnected |
||
1156 | jmp .ack_processed |
||
1733 | hidnplayr | 1157 | |
1772 | hidnplayr | 1158 | .ack_la: |
2891 | hidnplayr | 1159 | jnc .ack_processed |
1733 | hidnplayr | 1160 | |
2390 | hidnplayr | 1161 | mov eax, ebx |
2882 | hidnplayr | 1162 | call TCP_disconnect |
2390 | hidnplayr | 1163 | jmp .drop |
1733 | hidnplayr | 1164 | |
1772 | hidnplayr | 1165 | .ack_tw: |
2390 | hidnplayr | 1166 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
1167 | jmp .drop_after_ack |
||
1733 | hidnplayr | 1168 | |
2930 | hidnplayr | 1169 | .reset_dupacks: ; We got a new ACK, reset duplicate ACK counter |
1170 | mov [ebx + TCP_SOCKET.t_dupacks], 0 |
||
1171 | jmp .ack_processed |
||
1733 | hidnplayr | 1172 | |
3275 | hidnplayr | 1173 | ;------- |
1174 | ; LISTEN |
||
1772 | hidnplayr | 1175 | |
3275 | hidnplayr | 1176 | align 4 |
2930 | hidnplayr | 1177 | .LISTEN: |
1178 | |||
1179 | DEBUGF 1,"TCP_input: state=listen\n" |
||
1180 | |||
2937 | hidnplayr | 1181 | test [edx + TCP_header.Flags], TH_RST |
2930 | hidnplayr | 1182 | jnz .drop |
1183 | |||
1184 | test [edx + TCP_header.Flags], TH_ACK |
||
1185 | jnz .drop_with_reset |
||
1186 | |||
1187 | test [edx + TCP_header.Flags], TH_SYN |
||
1188 | jz .drop |
||
1189 | |||
1190 | ;;; TODO: check if it's a broadcast or multicast, and drop if so |
||
1191 | |||
1192 | push dword [edi] ; Ipv4 source addres |
||
1193 | pop [ebx + IP_SOCKET.RemoteIP] |
||
1194 | |||
1195 | push [edx + TCP_header.SourcePort] |
||
1196 | pop [ebx + TCP_SOCKET.RemotePort] |
||
1197 | |||
1198 | push [edx + TCP_header.SequenceNumber] |
||
1199 | pop [ebx + TCP_SOCKET.IRS] |
||
1200 | |||
1201 | mov eax, [TCP_sequence_num] |
||
1202 | add [TCP_sequence_num], 64000 / 2 |
||
1203 | mov [ebx + TCP_SOCKET.ISS], eax |
||
1204 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1205 | |||
1206 | TCP_sendseqinit ebx |
||
1207 | TCP_rcvseqinit ebx |
||
1208 | |||
1209 | mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
||
1210 | mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
||
1211 | mov [ebx + TCP_SOCKET.timer_keepalive], TCP_time_keep_interval ;;;; macro |
||
1212 | |||
1213 | lea eax, [ebx + STREAM_SOCKET.snd] |
||
1214 | call SOCKET_ring_create |
||
1215 | |||
1216 | lea eax, [ebx + STREAM_SOCKET.rcv] |
||
1217 | call SOCKET_ring_create |
||
1218 | |||
2937 | hidnplayr | 1219 | and [ebx + TCP_SOCKET.temp_bits], not TCP_BIT_DROPSOCKET |
1220 | |||
2930 | hidnplayr | 1221 | ;;; call SOCKET_notify_owner |
1222 | |||
1223 | jmp .trim_then_step6 |
||
1224 | |||
1225 | ;------------ |
||
1226 | ; Active Open |
||
1227 | |||
1228 | align 4 |
||
2937 | hidnplayr | 1229 | .SYN_SENT: |
2930 | hidnplayr | 1230 | |
1231 | DEBUGF 1,"TCP_input: state=syn_sent\n" |
||
1232 | |||
1233 | test [edx + TCP_header.Flags], TH_ACK |
||
1234 | jz @f |
||
1235 | |||
1236 | mov eax, [edx + TCP_header.AckNumber] |
||
1237 | cmp eax, [ebx + TCP_SOCKET.ISS] |
||
1238 | jbe .drop_with_reset |
||
1239 | |||
1240 | cmp eax, [ebx + TCP_SOCKET.SND_MAX] |
||
1241 | ja .drop_with_reset |
||
1242 | @@: |
||
1243 | |||
1244 | test [edx + TCP_header.Flags], TH_RST |
||
1245 | jz @f |
||
1246 | |||
1247 | test [edx + TCP_header.Flags], TH_ACK |
||
1248 | jz .drop |
||
1249 | |||
1250 | mov eax, ebx |
||
1251 | mov ebx, ECONNREFUSED |
||
1252 | call TCP_drop |
||
1253 | |||
1254 | jmp .drop |
||
1255 | @@: |
||
1256 | |||
1257 | test [edx + TCP_header.Flags], TH_SYN |
||
1258 | jz .drop |
||
1259 | |||
1260 | ; at this point, segment seems to be valid |
||
1261 | |||
1262 | test [edx + TCP_header.Flags], TH_ACK |
||
1263 | jz .no_syn_ack |
||
1264 | |||
1265 | ; now, process received SYN in response to an active open |
||
1266 | |||
1267 | mov eax, [edx + TCP_header.AckNumber] |
||
1268 | mov [ebx + TCP_SOCKET.SND_UNA], eax |
||
1269 | cmp eax, [ebx + TCP_SOCKET.SND_NXT] |
||
1270 | jbe @f |
||
1271 | mov [ebx + TCP_SOCKET.SND_NXT], eax |
||
1272 | @@: |
||
1273 | |||
1274 | .no_syn_ack: |
||
1275 | mov [ebx + TCP_SOCKET.timer_retransmission], 0 ; disable retransmission |
||
1276 | |||
1277 | push [edx + TCP_header.SequenceNumber] |
||
1278 | pop [ebx + TCP_SOCKET.IRS] |
||
1279 | |||
1280 | TCP_rcvseqinit ebx |
||
1281 | |||
1282 | or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
||
1283 | |||
1284 | mov eax, [ebx + TCP_SOCKET.SND_UNA] |
||
1285 | cmp eax, [ebx + TCP_SOCKET.ISS] |
||
1286 | jbe .simultaneous_open |
||
1287 | |||
1288 | test [edx + TCP_header.Flags], TH_ACK |
||
1289 | jz .simultaneous_open |
||
1290 | |||
1291 | DEBUGF 1,"TCP_input: active open\n" |
||
1292 | |||
1293 | ;;; TODO: update stats |
||
1294 | |||
1295 | ; set socket state to connected |
||
1296 | mov [ebx + SOCKET.state], SS_ISCONNECTED |
||
1297 | mov [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
||
1298 | |||
2937 | hidnplayr | 1299 | ; Do window scaling on this connection ? |
1300 | mov eax, [ebx + TCP_SOCKET.t_flags] |
||
1301 | and eax, TF_REQ_SCALE or TF_RCVD_SCALE |
||
1302 | cmp eax, TF_REQ_SCALE or TF_RCVD_SCALE |
||
1303 | jne .no_scaling |
||
2930 | hidnplayr | 1304 | |
2937 | hidnplayr | 1305 | mov ax, word [ebx + TCP_SOCKET.requested_s_scale] |
1306 | mov word [ebx + TCP_SOCKET.SND_SCALE], ax |
||
1307 | .no_scaling: |
||
2930 | hidnplayr | 1308 | |
2937 | hidnplayr | 1309 | ;;; TODO: reassemble packets queue |
1310 | |||
1311 | mov eax, [ebx + TCP_SOCKET.t_rtt] |
||
1312 | test eax, eax |
||
1313 | je .trim_then_step6 |
||
1314 | call TCP_xmit_timer |
||
2930 | hidnplayr | 1315 | jmp .trim_then_step6 |
1316 | |||
1317 | .simultaneous_open: |
||
1318 | |||
1319 | DEBUGF 1,"TCP_input: simultaneous open\n" |
||
1320 | ; We have received a syn but no ACK, so we are having a simultaneous open.. |
||
1321 | mov [ebx + TCP_SOCKET.t_state], TCPS_SYN_RECEIVED |
||
1322 | |||
1323 | ;------------------------------------- |
||
1324 | ; Common processing for receipt of SYN |
||
1325 | |||
1326 | .trim_then_step6: |
||
1327 | |||
1328 | inc [edx + TCP_header.SequenceNumber] |
||
1329 | |||
1330 | ;;; TODO: Drop any received data that follows receive window (590) |
||
1331 | |||
1332 | mov eax, [edx + TCP_header.SequenceNumber] |
||
1333 | mov [ebx + TCP_SOCKET.RCV_UP], eax |
||
1334 | dec eax |
||
1335 | mov [ebx + TCP_SOCKET.SND_WL1], eax |
||
1336 | |||
3275 | hidnplayr | 1337 | ;------- |
1338 | ; step 6 |
||
2930 | hidnplayr | 1339 | |
3275 | hidnplayr | 1340 | .ack_processed: |
2930 | hidnplayr | 1341 | |
2891 | hidnplayr | 1342 | DEBUGF 1,"TCP_input: ACK processed\n" |
1733 | hidnplayr | 1343 | |
1344 | ;---------------------------------------------- |
||
1345 | ; check if we need to update window information |
||
1346 | |||
2390 | hidnplayr | 1347 | test [edx + TCP_header.Flags], TH_ACK |
1348 | jz .no_window_update |
||
1733 | hidnplayr | 1349 | |
2390 | hidnplayr | 1350 | mov eax, [ebx + TCP_SOCKET.SND_WL1] |
1351 | cmp eax, [edx + TCP_header.SequenceNumber] |
||
1352 | jb .update_window |
||
1353 | ja @f |
||
1733 | hidnplayr | 1354 | |
2390 | hidnplayr | 1355 | mov eax, [ebx + TCP_SOCKET.SND_WL2] |
1356 | cmp eax, [edx + TCP_header.AckNumber] |
||
1357 | jb .update_window |
||
1358 | ja .no_window_update |
||
1733 | hidnplayr | 1359 | @@: |
1360 | |||
2390 | hidnplayr | 1361 | mov eax, dword [edx + TCP_header.Window] |
1362 | cmp eax, [ebx + TCP_SOCKET.SND_WND] |
||
1363 | jbe .no_window_update |
||
1733 | hidnplayr | 1364 | |
1365 | .update_window: |
||
1366 | |||
2954 | hidnplayr | 1367 | ;;; TODO: update stats (Keep track of pure window updates) |
1733 | hidnplayr | 1368 | |
2390 | hidnplayr | 1369 | mov eax, dword [edx + TCP_header.Window] |
1370 | cmp eax, [ebx + TCP_SOCKET.max_sndwnd] |
||
1371 | jbe @f |
||
1372 | mov [ebx + TCP_SOCKET.max_sndwnd], eax |
||
1733 | hidnplayr | 1373 | @@: |
2390 | hidnplayr | 1374 | mov [ebx + TCP_SOCKET.SND_WND], eax |
1733 | hidnplayr | 1375 | |
2891 | hidnplayr | 1376 | DEBUGF 1,"TCP_input: Updating window to %u\n", eax |
2612 | hidnplayr | 1377 | |
2390 | hidnplayr | 1378 | push [edx + TCP_header.SequenceNumber] |
1379 | pop [ebx + TCP_SOCKET.SND_WL1] |
||
1733 | hidnplayr | 1380 | |
2390 | hidnplayr | 1381 | push [edx + TCP_header.AckNumber] |
1382 | pop [ebx + TCP_SOCKET.SND_WL2] |
||
1733 | hidnplayr | 1383 | |
2937 | hidnplayr | 1384 | or [ebx + TCP_SOCKET.temp_bits], TCP_BIT_NEEDOUTPUT |
1733 | hidnplayr | 1385 | |
1386 | .no_window_update: |
||
1387 | |||
1388 | ;----------------- |
||
1389 | ; process URG flag |
||
1390 | |||
2390 | hidnplayr | 1391 | test [edx + TCP_header.Flags], TH_URG |
1392 | jz .not_urgent |
||
1733 | hidnplayr | 1393 | |
2390 | hidnplayr | 1394 | cmp [edx + TCP_header.UrgentPointer], 0 |
1395 | jz .not_urgent |
||
1733 | hidnplayr | 1396 | |
2390 | hidnplayr | 1397 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1398 | je .not_urgent |
||
1733 | hidnplayr | 1399 | |
1400 | ; Ignore bogus urgent offsets |
||
1401 | |||
2390 | hidnplayr | 1402 | movzx eax, [edx + TCP_header.UrgentPointer] |
1403 | add eax, [ebx + STREAM_SOCKET.rcv.size] |
||
1404 | cmp eax, SOCKET_MAXDATA |
||
1405 | jbe .not_urgent |
||
1733 | hidnplayr | 1406 | |
2390 | hidnplayr | 1407 | mov [edx + TCP_header.UrgentPointer], 0 |
1408 | and [edx + TCP_header.Flags], not (TH_URG) |
||
1409 | jmp .do_data |
||
1733 | hidnplayr | 1410 | |
1411 | .not_urgent: |
||
1412 | |||
1413 | ; processing of received urgent pointer |
||
1414 | |||
2390 | hidnplayr | 1415 | ;;; TODO (1051-1093) |
1733 | hidnplayr | 1416 | |
1417 | |||
2891 | hidnplayr | 1418 | ;--------------------------------------- |
1419 | ; process the data in the segment (1094) |
||
1733 | hidnplayr | 1420 | |
1421 | .do_data: |
||
1422 | |||
2891 | hidnplayr | 1423 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1424 | jae .final_processing |
||
1733 | hidnplayr | 1425 | |
2390 | hidnplayr | 1426 | test [edx + TCP_header.Flags], TH_FIN |
2891 | hidnplayr | 1427 | jnz @f |
1733 | hidnplayr | 1428 | |
2390 | hidnplayr | 1429 | test ecx, ecx |
2891 | hidnplayr | 1430 | jnz .final_processing |
1431 | @@: |
||
1733 | hidnplayr | 1432 | |
1433 | |||
3406 | hidnplayr | 1434 | ; The segment is in order? |
1435 | mov eax, [edx + TCP_header.SequenceNumber] |
||
1436 | cmp eax, [ebx + TCP_SOCKET.RCV_NXT] |
||
1437 | jne .out_of_order |
||
1438 | |||
1439 | ; The reassembly queue is empty? |
||
1440 | cmp [ebx + TCP_SOCKET.seg_next], 0 |
||
1441 | jne .out_of_order |
||
1442 | |||
1443 | ; The connection is established? |
||
1444 | cmp [ebx + TCP_SOCKET.t_state], TCPS_ESTABLISHED |
||
1445 | jne .out_of_order |
||
1446 | |||
1447 | ; Ok, lets do this.. Set delayed ACK flag and copy data into socket buffer |
||
1448 | or [ebx + TCP_SOCKET.t_flags], TF_DELACK |
||
1449 | |||
1450 | pusha |
||
1451 | movzx esi, [edx + TCP_header.DataOffset] |
||
1452 | add esi, edx |
||
1453 | lea eax, [ebx + STREAM_SOCKET.rcv] |
||
1454 | call SOCKET_ring_write ; Add the data to the socket buffer |
||
1455 | add [ebx + TCP_SOCKET.RCV_NXT], ecx ; Update sequence number with number of bytes we have copied |
||
1456 | popa |
||
1457 | |||
1458 | ; Wake up the sleeping process |
||
1459 | mov eax, ebx |
||
1460 | call SOCKET_notify |
||
1461 | |||
1462 | jmp .data_done |
||
1463 | |||
1464 | .out_of_order: |
||
1465 | |||
1466 | ; Uh-oh, some data is out of order, lets call TCP reassemble for help |
||
1467 | |||
1468 | call TCP_reassemble |
||
1469 | |||
1470 | DEBUGF 1, "1470\n" |
||
1471 | or [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
||
1472 | |||
1473 | .data_done: |
||
1474 | |||
1733 | hidnplayr | 1475 | ;--------------- |
1476 | ; FIN processing |
||
1477 | |||
2891 | hidnplayr | 1478 | test [edx + TCP_header.Flags], TH_FIN |
2930 | hidnplayr | 1479 | jz .final_processing |
1733 | hidnplayr | 1480 | |
2891 | hidnplayr | 1481 | DEBUGF 1,"TCP_input: Processing FIN\n" |
1733 | hidnplayr | 1482 | |
2891 | hidnplayr | 1483 | cmp [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1484 | jae .not_first_fin |
||
1774 | hidnplayr | 1485 | |
2891 | hidnplayr | 1486 | DEBUGF 1,"TCP_input: First FIN for this connection\n" |
1774 | hidnplayr | 1487 | |
2390 | hidnplayr | 1488 | mov eax, ebx |
1489 | call SOCKET_cant_recv_more |
||
1774 | hidnplayr | 1490 | |
2390 | hidnplayr | 1491 | mov [ebx + TCP_SOCKET.t_flags], TF_ACKNOW |
1492 | inc [ebx + TCP_SOCKET.RCV_NXT] |
||
1774 | hidnplayr | 1493 | |
1494 | .not_first_fin: |
||
2390 | hidnplayr | 1495 | mov eax, [ebx + TCP_SOCKET.t_state] |
1496 | shl eax, 2 |
||
1497 | jmp dword [eax + .FIN_sw_list] |
||
1733 | hidnplayr | 1498 | |
1499 | .FIN_sw_list: |
||
2937 | hidnplayr | 1500 | dd .final_processing ; TCPS_CLOSED |
1501 | dd .final_processing ; TCPS_LISTEN |
||
1502 | dd .final_processing ; TCPS_SYN_SENT |
||
1503 | dd .fin_syn_est ; TCPS_SYN_RECEIVED |
||
1504 | dd .fin_syn_est ; TCPS_ESTABLISHED |
||
1505 | dd .final_processing ; TCPS_CLOSE_WAIT |
||
1506 | dd .fin_wait1 ; TCPS_FIN_WAIT_1 |
||
1507 | dd .final_processing ; TCPS_CLOSING |
||
1508 | dd .final_processing ; TCPS_LAST_ACK |
||
1509 | dd .fin_wait2 ; TCPS_FIN_WAIT_2 |
||
1510 | dd .fin_timed ; TCPS_TIMED_WAIT |
||
1733 | hidnplayr | 1511 | |
1512 | .fin_syn_est: |
||
1513 | |||
2390 | hidnplayr | 1514 | mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSE_WAIT |
2930 | hidnplayr | 1515 | jmp .final_processing |
1733 | hidnplayr | 1516 | |
1517 | .fin_wait1: |
||
1518 | |||
2390 | hidnplayr | 1519 | mov [ebx + TCP_SOCKET.t_state], TCPS_CLOSING |
2930 | hidnplayr | 1520 | jmp .final_processing |
1733 | hidnplayr | 1521 | |
1522 | .fin_wait2: |
||
1523 | |||
2390 | hidnplayr | 1524 | mov [ebx + TCP_SOCKET.t_state], TCPS_TIMED_WAIT |
1525 | mov eax, ebx |
||
1526 | call TCP_cancel_timers |
||
1527 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
||
1528 | call SOCKET_is_disconnected |
||
2930 | hidnplayr | 1529 | jmp .final_processing |
1733 | hidnplayr | 1530 | |
1531 | .fin_timed: |
||
2390 | hidnplayr | 1532 | mov [ebx + TCP_SOCKET.timer_timed_wait], 2 * TCP_time_MSL |
2930 | hidnplayr | 1533 | jmp .final_processing |
1733 | hidnplayr | 1534 | |
1535 | |||
2930 | hidnplayr | 1536 | .drop_after_ack: |
1537 | DEBUGF 1,"TCP_input: Drop after ACK\n" |
||
1733 | hidnplayr | 1538 | |
2930 | hidnplayr | 1539 | push edx ebx |
2891 | hidnplayr | 1540 | lea ecx, [ebx + SOCKET.mutex] |
1541 | call mutex_unlock |
||
2930 | hidnplayr | 1542 | pop eax edx |
2891 | hidnplayr | 1543 | |
2930 | hidnplayr | 1544 | test [edx + TCP_header.Flags], TH_RST |
1545 | jnz .dumpit |
||
1733 | hidnplayr | 1546 | |
2930 | hidnplayr | 1547 | or [eax + TCP_SOCKET.t_flags], TF_ACKNOW |
1548 | jmp .need_output |
||
2891 | hidnplayr | 1549 | |
2930 | hidnplayr | 1550 | .drop_with_reset: |
1551 | DEBUGF 1,"TCP_input: Drop with reset\n" |
||
1552 | |||
1553 | push ebx edx |
||
2402 | hidnplayr | 1554 | lea ecx, [ebx + SOCKET.mutex] |
1555 | call mutex_unlock |
||
2930 | hidnplayr | 1556 | pop edx ebx |
1733 | hidnplayr | 1557 | |
2930 | hidnplayr | 1558 | test [edx + TCP_header.Flags], TH_RST |
1559 | jnz .dumpit |
||
1733 | hidnplayr | 1560 | |
2930 | hidnplayr | 1561 | ;;; if its a multicast/broadcast, also drop |
1733 | hidnplayr | 1562 | |
2930 | hidnplayr | 1563 | test [edx + TCP_header.Flags], TH_ACK |
1564 | jnz .respond_ack |
||
1733 | hidnplayr | 1565 | |
2930 | hidnplayr | 1566 | test [edx + TCP_header.Flags], TH_SYN |
1567 | jnz .respond_syn |
||
1568 | jmp .dumpit |
||
1733 | hidnplayr | 1569 | |
2930 | hidnplayr | 1570 | ;----------------- |
1571 | ; Final processing |
||
1733 | hidnplayr | 1572 | |
2930 | hidnplayr | 1573 | .final_processing: |
1574 | DEBUGF 1,"TCP_input: Final processing\n" |
||
1733 | hidnplayr | 1575 | |
2930 | hidnplayr | 1576 | push ebx |
1577 | lea ecx, [ebx + SOCKET.mutex] |
||
1578 | call mutex_unlock |
||
1579 | pop eax |
||
1733 | hidnplayr | 1580 | |
2937 | hidnplayr | 1581 | test [eax + TCP_SOCKET.temp_bits], TCP_BIT_NEEDOUTPUT |
1582 | jnz .need_output |
||
1733 | hidnplayr | 1583 | |
2930 | hidnplayr | 1584 | test [eax + TCP_SOCKET.t_flags], TF_ACKNOW |
1585 | jz .dumpit |
||
1586 | DEBUGF 1,"TCP_input: ACK now!\n" |
||
1733 | hidnplayr | 1587 | |
2930 | hidnplayr | 1588 | .need_output: |
2954 | hidnplayr | 1589 | DEBUGF 1,"TCP_input: need output\n" |
2930 | hidnplayr | 1590 | call TCP_output |
1733 | hidnplayr | 1591 | |
2930 | hidnplayr | 1592 | .dumpit: |
1593 | DEBUGF 1,"TCP_input: dumping\n" |
||
1733 | hidnplayr | 1594 | |
2390 | hidnplayr | 1595 | call kernel_free |
1596 | add esp, 4 |
||
3406 | hidnplayr | 1597 | jmp .loop |
1733 | hidnplayr | 1598 | |
3275 | hidnplayr | 1599 | ;--------- |
1600 | ; Respond |
||
1733 | hidnplayr | 1601 | |
1602 | .respond_ack: |
||
2390 | hidnplayr | 1603 | push ebx |
1604 | mov cl, TH_RST |
||
3143 | hidnplayr | 1605 | call TCP_respond |
2390 | hidnplayr | 1606 | pop ebx |
1607 | jmp .destroy_new_socket |
||
1733 | hidnplayr | 1608 | |
1609 | .respond_syn: |
||
2390 | hidnplayr | 1610 | push ebx |
1611 | mov cl, TH_RST + TH_ACK |
||
3143 | hidnplayr | 1612 | call TCP_respond |
2390 | hidnplayr | 1613 | pop ebx |
1614 | jmp .destroy_new_socket |
||
1733 | hidnplayr | 1615 | |
3275 | hidnplayr | 1616 | .respond_seg_reset: |
1617 | test [edx + TCP_header.Flags], TH_RST |
||
1618 | jnz .drop_no_socket |
||
1733 | hidnplayr | 1619 | |
3275 | hidnplayr | 1620 | ;;; TODO: if its a multicast/broadcast, also drop |
1733 | hidnplayr | 1621 | |
3275 | hidnplayr | 1622 | test [edx + TCP_header.Flags], TH_ACK |
1623 | jnz .respond_seg_ack |
||
1624 | |||
1625 | test [edx + TCP_header.Flags], TH_SYN |
||
1626 | jnz .respond_seg_syn |
||
1627 | |||
1628 | jmp .drop_no_socket |
||
1629 | |||
1630 | .respond_seg_ack: |
||
1631 | mov cl, TH_RST |
||
1632 | call TCP_respond_segment |
||
1633 | jmp .drop_no_socket |
||
1634 | |||
1635 | .respond_seg_syn: |
||
1636 | mov cl, TH_RST + TH_ACK |
||
1637 | call TCP_respond_segment |
||
1638 | jmp .drop_no_socket |
||
1639 | |||
1733 | hidnplayr | 1640 | ;----- |
1641 | ; Drop |
||
1642 | |||
2930 | hidnplayr | 1643 | .drop: |
3275 | hidnplayr | 1644 | DEBUGF 1,"TCP_input: Dropping segment\n" |
1733 | hidnplayr | 1645 | |
2402 | hidnplayr | 1646 | pusha |
1647 | lea ecx, [ebx + SOCKET.mutex] |
||
1648 | call mutex_unlock |
||
1649 | popa |
||
1733 | hidnplayr | 1650 | |
2937 | hidnplayr | 1651 | .destroy_new_socket: |
1652 | test [ebx + TCP_SOCKET.temp_bits], TCP_BIT_DROPSOCKET |
||
1653 | jz .drop_no_socket |
||
1733 | hidnplayr | 1654 | |
2937 | hidnplayr | 1655 | mov eax, ebx |
1656 | call SOCKET_free |
||
1733 | hidnplayr | 1657 | |
2930 | hidnplayr | 1658 | .drop_no_socket: |
1659 | DEBUGF 1,"TCP_input: Drop (no socket)\n" |
||
1660 | |||
2390 | hidnplayr | 1661 | call kernel_free |
1662 | add esp, 4 |
||
3406 | hidnplayr | 1663 | jmp .loop |