1 // Copyright (c) 2012 Pieter Wuille
2 // Distributed under the MIT/X11 software license, see the accompanying
3 // file license.txt or http://www.opensource.org/licenses/mit-license.php.
9 int CAddrInfo::GetTriedBucket(const std::vector<unsigned char> &nKey) const
11 CDataStream ss1(SER_GETHASH);
12 std::vector<unsigned char> vchKey = GetKey();
13 ss1 << nKey << vchKey;
14 uint64 hash1 = Hash(ss1.begin(), ss1.end()).Get64();
16 CDataStream ss2(SER_GETHASH);
17 std::vector<unsigned char> vchGroupKey = GetGroup();
18 ss2 << nKey << vchGroupKey << (hash1 % ADDRMAN_TRIED_BUCKETS_PER_GROUP);
19 uint64 hash2 = Hash(ss2.begin(), ss2.end()).Get64();
20 return hash2 % ADDRMAN_TRIED_BUCKET_COUNT;
23 int CAddrInfo::GetNewBucket(const std::vector<unsigned char> &nKey, const CNetAddr& src) const
25 CDataStream ss1(SER_GETHASH);
26 std::vector<unsigned char> vchGroupKey = GetGroup();
27 std::vector<unsigned char> vchSourceGroupKey = src.GetGroup();
28 ss1 << nKey << vchGroupKey << vchSourceGroupKey;
29 uint64 hash1 = Hash(ss1.begin(), ss1.end()).Get64();
31 CDataStream ss2(SER_GETHASH);
32 ss2 << nKey << vchSourceGroupKey << (hash1 % ADDRMAN_NEW_BUCKETS_PER_SOURCE_GROUP);
33 uint64 hash2 = Hash(ss2.begin(), ss2.end()).Get64();
34 return hash2 % ADDRMAN_NEW_BUCKET_COUNT;
37 bool CAddrInfo::IsTerrible(int64 nNow) const
39 if (nLastTry && nLastTry >= nNow-60) // never remove things tried the last minute
42 if (nTime > nNow + 10*60) // came in a flying DeLorean
45 if (nTime==0 || nNow-nTime > ADDRMAN_HORIZON_DAYS*86400) // not seen in over a month
48 if (nLastSuccess==0 && nAttempts>=ADDRMAN_RETRIES) // tried three times and never a success
51 if (nNow-nLastSuccess > ADDRMAN_MIN_FAIL_DAYS*86400 && nAttempts>=ADDRMAN_MAX_FAILURES) // 10 successive failures in the last week
57 double CAddrInfo::GetChance(int64 nNow) const
61 int64 nSinceLastSeen = nNow - nTime;
62 int64 nSinceLastTry = nNow - nLastTry;
64 if (nSinceLastSeen < 0) nSinceLastSeen = 0;
65 if (nSinceLastTry < 0) nSinceLastTry = 0;
67 fChance *= 600.0 / (600.0 + nSinceLastSeen);
69 // deprioritize very recent attempts away
70 if (nSinceLastTry < 60*10)
73 // deprioritize 50% after each failed attempt
74 for (int n=0; n<nAttempts; n++)
80 CAddrInfo* CAddrMan::Find(const CNetAddr& addr, int *pnId)
82 std::map<CNetAddr, int>::iterator it = mapAddr.find(addr);
83 if (it == mapAddr.end())
87 std::map<int, CAddrInfo>::iterator it2 = mapInfo.find((*it).second);
88 if (it2 != mapInfo.end())
89 return &(*it2).second;
93 CAddrInfo* CAddrMan::Create(const CAddress &addr, const CNetAddr &addrSource, int *pnId)
96 mapInfo[nId] = CAddrInfo(addr, addrSource);
98 mapInfo[nId].nRandomPos = vRandom.size();
99 vRandom.push_back(nId);
102 return &mapInfo[nId];
105 void CAddrMan::SwapRandom(int nRndPos1, int nRndPos2)
107 if (nRndPos1 == nRndPos2)
110 int nId1 = vRandom[nRndPos1];
111 int nId2 = vRandom[nRndPos2];
113 mapInfo[nId1].nRandomPos = nRndPos2;
114 mapInfo[nId2].nRandomPos = nRndPos1;
116 vRandom[nRndPos1] = nId2;
117 vRandom[nRndPos2] = nId1;
120 int CAddrMan::SelectTried(int nKBucket)
122 std::vector<int> &vTried = vvTried[nKBucket];
124 // random shuffle the first few elements (using the entire list)
125 // find the least recently tried among them
128 for (unsigned int i = 0; i < ADDRMAN_TRIED_ENTRIES_INSPECT_ON_EVICT && i < vTried.size(); i++)
130 int nPos = GetRandInt(vTried.size() - i) + i;
131 int nTemp = vTried[nPos];
132 vTried[nPos] = vTried[i];
134 if (nOldest == -1 || mapInfo[nTemp].nLastSuccess < mapInfo[nOldest].nLastSuccess) {
143 int CAddrMan::ShrinkNew(int nUBucket)
145 std::set<int> &vNew = vvNew[nUBucket];
147 // first look for deletable items
148 for (std::set<int>::iterator it = vNew.begin(); it != vNew.end(); it++)
150 CAddrInfo &info = mapInfo[*it];
151 if (info.IsTerrible())
153 if (--info.nRefCount == 0)
155 SwapRandom(info.nRandomPos, vRandom.size()-1);
166 // otherwise, select four randomly, and pick the oldest of those to replace
167 int n[4] = {GetRandInt(vNew.size()), GetRandInt(vNew.size()), GetRandInt(vNew.size()), GetRandInt(vNew.size())};
170 for (std::set<int>::iterator it = vNew.begin(); it != vNew.end(); it++)
172 if (nI == n[0] || nI == n[1] || nI == n[2] || nI == n[3])
174 if (nOldest == -1 || mapInfo[*it].nTime < mapInfo[nOldest].nTime)
179 CAddrInfo &info = mapInfo[nOldest];
180 if (--info.nRefCount == 0)
182 SwapRandom(info.nRandomPos, vRandom.size()-1);
185 mapInfo.erase(nOldest);
193 void CAddrMan::MakeTried(CAddrInfo& info, int nId, int nOrigin)
195 // remove the entry from all new buckets
196 for (std::vector<std::set<int> >::iterator it = vvNew.begin(); it != vvNew.end(); it++)
198 if ((*it).erase(nId))
203 // what tried bucket to move the entry to
204 int nKBucket = info.GetTriedBucket(nKey);
205 std::vector<int> &vTried = vvTried[nKBucket];
207 // first check whether there is place to just add it
208 if (vTried.size() < ADDRMAN_TRIED_BUCKET_SIZE)
210 vTried.push_back(nId);
212 info.fInTried = true;
216 // otherwise, find an item to evict
217 int nPos = SelectTried(nKBucket);
219 // find which new bucket it belongs to
220 int nUBucket = mapInfo[vTried[nPos]].GetNewBucket(nKey);
221 std::set<int> &vNew = vvNew[nUBucket];
223 // remove the to-be-replaced tried entry from the tried set
224 CAddrInfo& infoOld = mapInfo[vTried[nPos]];
225 infoOld.fInTried = false;
226 infoOld.nRefCount = 1;
227 // do not update nTried, as we are going to move something else there immediately
229 // check whether there is place in that one,
230 if (vNew.size() < ADDRMAN_NEW_BUCKET_SIZE)
232 // if so, move it back there
233 vNew.insert(vTried[nPos]);
235 // otherwise, move it to the new bucket nId came from (there is certainly place there)
236 vvNew[nOrigin].insert(vTried[nPos]);
241 // we just overwrote an entry in vTried; no need to update nTried
242 info.fInTried = true;
246 void CAddrMan::Good_(const CService &addr, int64 nTime)
248 // printf("Good: addr=%s\n", addr.ToString().c_str());
251 CAddrInfo *pinfo = Find(addr, &nId);
253 // if not found, bail out
257 CAddrInfo &info = *pinfo;
259 // check whether we are talking about the exact same CService (including same port)
264 info.nLastSuccess = nTime;
265 info.nLastTry = nTime;
269 // if it is already in the tried set, don't do anything else
273 // find a bucket it is in now
274 int nRnd = GetRandInt(vvNew.size());
276 for (unsigned int n = 0; n < vvNew.size(); n++)
278 int nB = (n+nRnd) % vvNew.size();
279 std::set<int> &vNew = vvNew[nB];
287 // if no bucket is found, something bad happened;
288 // TODO: maybe re-add the node, but for now, just bail out
289 if (nUBucket == -1) return;
291 printf("Moving %s to tried\n", addr.ToString().c_str());
293 // move nId to the tried tables
294 MakeTried(info, nId, nUBucket);
297 bool CAddrMan::Add_(const CAddress &addr, const CNetAddr& source, int64 nTimePenalty)
299 if (!addr.IsRoutable())
304 CAddrInfo *pinfo = Find(addr, &nId);
308 // periodically update nTime
309 bool fCurrentlyOnline = (GetAdjustedTime() - addr.nTime < 24 * 60 * 60);
310 int64 nUpdateInterval = (fCurrentlyOnline ? 60 * 60 : 24 * 60 * 60);
311 if (addr.nTime && (!pinfo->nTime || pinfo->nTime < addr.nTime - nUpdateInterval - nTimePenalty))
312 pinfo->nTime = max((int64)0, addr.nTime - nTimePenalty);
315 pinfo->nServices |= addr.nServices;
317 // do not update if no new information is present
318 if (!addr.nTime || (pinfo->nTime && addr.nTime <= pinfo->nTime))
321 // do not update if the entry was already in the "tried" table
325 // do not update if the max reference count is reached
326 if (pinfo->nRefCount == ADDRMAN_NEW_BUCKETS_PER_ADDRESS)
329 // stochastic test: previous nRefCount == N: 2^N times harder to increase it
331 for (int n=0; n<pinfo->nRefCount; n++)
333 if (nFactor > 1 && (GetRandInt(nFactor) != 0))
336 pinfo = Create(addr, source, &nId);
337 pinfo->nTime = max((int64)0, (int64)pinfo->nTime - nTimePenalty);
338 // printf("Added %s [nTime=%fhr]\n", pinfo->ToString().c_str(), (GetAdjustedTime() - pinfo->nTime) / 3600.0);
343 int nUBucket = pinfo->GetNewBucket(nKey, source);
344 std::set<int> &vNew = vvNew[nUBucket];
345 if (!vNew.count(nId))
348 if (vNew.size() == ADDRMAN_NEW_BUCKET_SIZE)
350 vvNew[nUBucket].insert(nId);
355 void CAddrMan::Attempt_(const CService &addr, int64 nTime)
357 CAddrInfo *pinfo = Find(addr);
359 // if not found, bail out
363 CAddrInfo &info = *pinfo;
365 // check whether we are talking about the exact same CService (including same port)
370 info.nLastTry = nTime;
374 CAddress CAddrMan::Select_(int nUnkBias)
379 double nCorTried = sqrt(nTried) * (100.0 - nUnkBias);
380 double nCorNew = sqrt(nNew) * nUnkBias;
381 if ((nCorTried + nCorNew)*GetRandInt(1<<30)/(1<<30) < nCorTried)
384 double fChanceFactor = 1.0;
387 int nKBucket = GetRandInt(vvTried.size());
388 std::vector<int> &vTried = vvTried[nKBucket];
389 if (vTried.size() == 0) continue;
390 int nPos = GetRandInt(vTried.size());
391 CAddrInfo &info = mapInfo[vTried[nPos]];
392 if (GetRandInt(1<<30) < fChanceFactor*info.GetChance()*(1<<30))
394 fChanceFactor *= 1.2;
398 double fChanceFactor = 1.0;
401 int nUBucket = GetRandInt(vvNew.size());
402 std::set<int> &vNew = vvNew[nUBucket];
403 if (vNew.size() == 0) continue;
404 int nPos = GetRandInt(vNew.size());
405 std::set<int>::iterator it = vNew.begin();
408 CAddrInfo &info = mapInfo[*it];
409 if (GetRandInt(1<<30) < fChanceFactor*info.GetChance()*(1<<30))
411 fChanceFactor *= 1.2;
417 int CAddrMan::Check_()
419 std::set<int> setTried;
420 std::map<int, int> mapNew;
422 if (vRandom.size() != nTried + nNew) return -7;
424 for (std::map<int, CAddrInfo>::iterator it = mapInfo.begin(); it != mapInfo.end(); it++)
427 CAddrInfo &info = (*it).second;
431 if (!info.nLastSuccess) return -1;
432 if (info.nRefCount) return -2;
435 if (info.nRefCount < 0 || info.nRefCount > ADDRMAN_NEW_BUCKETS_PER_ADDRESS) return -3;
436 if (!info.nRefCount) return -4;
437 mapNew[n] = info.nRefCount;
439 if (mapAddr[info] != n) return -5;
440 if (info.nRandomPos<0 || info.nRandomPos>=vRandom.size() || vRandom[info.nRandomPos] != n) return -14;
441 if (info.nLastTry < 0) return -6;
442 if (info.nLastSuccess < 0) return -8;
445 if (setTried.size() != nTried) return -9;
446 if (mapNew.size() != nNew) return -10;
448 for (int n=0; n<vvTried.size(); n++)
450 std::vector<int> &vTried = vvTried[n];
451 for (std::vector<int>::iterator it = vTried.begin(); it != vTried.end(); it++)
453 if (!setTried.count(*it)) return -11;
458 for (int n=0; n<vvNew.size(); n++)
460 std::set<int> &vNew = vvNew[n];
461 for (std::set<int>::iterator it = vNew.begin(); it != vNew.end(); it++)
463 if (!mapNew.count(*it)) return -12;
464 if (--mapNew[*it] == 0)
469 if (setTried.size()) return -13;
470 if (mapNew.size()) return -15;
476 void CAddrMan::GetAddr_(std::vector<CAddress> &vAddr)
478 int nNodes = ADDRMAN_GETADDR_MAX_PCT*vRandom.size()/100;
479 if (nNodes > ADDRMAN_GETADDR_MAX)
480 nNodes = ADDRMAN_GETADDR_MAX;
482 // perform a random shuffle over the first nNodes elements of vRandom (selecting from all)
483 for (int n = 0; n<nNodes; n++)
485 int nRndPos = GetRandInt(vRandom.size() - n) + n;
486 SwapRandom(n, nRndPos);
487 vAddr.push_back(mapInfo[vRandom[n]]);
491 void CAddrMan::Connected_(const CService &addr, int64 nTime)
493 CAddrInfo *pinfo = Find(addr);
495 // if not found, bail out
499 CAddrInfo &info = *pinfo;
501 // check whether we are talking about the exact same CService (including same port)
506 int64 nUpdateInterval = 20 * 60;
507 if (nTime - info.nTime > nUpdateInterval)