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| 160 | bool can (sockinfo &si) { return u32_rate_limiter::can((u32)si.host); } |
160 | bool can (sockinfo &si) { return u32_rate_limiter::can((u32)si.host); } |
| 161 | |
161 | |
| 162 | net_rate_limiter (time_t every) : u32_rate_limiter (every) {} |
162 | net_rate_limiter (time_t every) : u32_rate_limiter (every) {} |
| 163 | }; |
163 | }; |
| 164 | |
164 | |
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165 | struct sliding_window { |
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166 | u32 v[(WINDOWSIZE + 31) / 32]; |
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167 | u32 seq; |
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168 | |
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169 | void reset (u32 seqno) |
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170 | { |
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171 | memset (v, -1, sizeof v); |
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172 | seq = seqno; |
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173 | } |
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174 | |
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175 | bool recv_ok (u32 seqno) |
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176 | { |
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177 | if (seqno <= seq - WINDOWSIZE) |
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178 | slog (L_ERR, _("received duplicate or outdated packet (received %08lx, expected %08lx)\n" |
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179 | "possible replay attack, or just massive packet reordering"), seqno, seq + 1);//D |
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180 | else if (seqno > seq + WINDOWSIZE) |
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181 | slog (L_ERR, _("received duplicate or out-of-sync packet (received %08lx, expected %08lx)\n" |
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182 | "possible replay attack, or just massive packet loss"), seqno, seq + 1);//D |
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183 | else |
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184 | { |
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185 | while (seqno > seq) |
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186 | { |
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187 | seq++; |
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188 | |
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189 | u32 s = seq % WINDOWSIZE; |
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190 | u32 *cell = v + (s >> 5); |
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191 | u32 mask = 1 << (s & 31); |
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192 | |
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193 | *cell &= ~mask; |
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194 | } |
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195 | |
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196 | u32 s = seqno % WINDOWSIZE; |
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197 | u32 *cell = v + (s >> 5); |
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198 | u32 mask = 1 << (s & 31); |
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199 | |
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200 | //printf ("received seqno %08lx, seq %08lx, mask %08lx is %08lx\n", seqno, seq, mask, ismask); |
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201 | if (*cell & mask) |
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202 | { |
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203 | slog (L_ERR, _("received duplicate packet (received %08lx, expected %08lx)\n" |
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204 | "possible replay attack, or just packet duplication"), seqno, seq + 1);//D |
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205 | return false; |
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206 | } |
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207 | else |
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208 | { |
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209 | *cell |= mask; |
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210 | return true; |
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211 | } |
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212 | } |
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213 | } |
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214 | }; |
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215 | |
| 165 | #endif |
216 | #endif |
| 166 | |
217 | |
