diff --git a/src/addrman.cpp b/src/addrman.cpp index 9eefffb45..9a7fad490 100644 --- a/src/addrman.cpp +++ b/src/addrman.cpp @@ -187,7 +187,7 @@ void CAddrMan::MakeTried(CAddrInfo& info, int nId) info.fInTried = true; } -void CAddrMan::Good_(const CService& addr, int64_t nTime) +void CAddrMan::Good_(const CService& addr, bool test_before_evict, int64_t nTime) { int nId; @@ -233,10 +233,22 @@ void CAddrMan::Good_(const CService& addr, int64_t nTime) if (nUBucket == -1) return; - LogPrint(BCLog::ADDRMAN, "Moving %s to tried\n", addr.ToString()); + // which tried bucket to move the entry to + int tried_bucket = info.GetTriedBucket(nKey); + int tried_bucket_pos = info.GetBucketPosition(nKey, false, tried_bucket); - // move nId to the tried tables - MakeTried(info, nId); + // Will moving this address into tried evict another entry? + if (test_before_evict && (vvTried[tried_bucket][tried_bucket_pos] != -1)) { + LogPrint(BCLog::ADDRMAN, "addrman", "Collision inserting element into tried table, moving %s to m_tried_collisions=%d\n", addr.ToString(), m_tried_collisions.size()); + if (m_tried_collisions.size() < ADDRMAN_SET_TRIED_COLLISION_SIZE) { + m_tried_collisions.insert(nId); + } + } else { + LogPrint(BCLog::ADDRMAN, "Moving %s to tried\n", addr.ToString()); + + // move nId to the tried tables + MakeTried(info, nId); + } } bool CAddrMan::Add_(const CAddress& addr, const CNetAddr& source, int64_t nTimePenalty) @@ -521,3 +533,82 @@ void CAddrMan::SetServices_(const CService& addr, ServiceFlags nServices) int CAddrMan::RandomInt(int nMax){ return GetRandInt(nMax); } + +void CAddrMan::ResolveCollisions_() +{ + for (std::set::iterator it = m_tried_collisions.begin(); it != m_tried_collisions.end();) { + int id_new = *it; + + bool erase_collision = false; + + // If id_new not found in mapInfo remove it from m_tried_collisions + if (mapInfo.count(id_new) != 1) { + erase_collision = true; + } else { + CAddrInfo& info_new = mapInfo[id_new]; + + // Which tried bucket to move the entry to. + int tried_bucket = info_new.GetTriedBucket(nKey); + int tried_bucket_pos = info_new.GetBucketPosition(nKey, false, tried_bucket); + if (!info_new.IsValid()) { // id_new may no longer map to a valid address + erase_collision = true; + } else if (vvTried[tried_bucket][tried_bucket_pos] != -1) { // The position in the tried bucket is not empty + + // Get the to-be-evicted address that is being tested + int id_old = vvTried[tried_bucket][tried_bucket_pos]; + CAddrInfo& info_old = mapInfo[id_old]; + + // Has successfully connected in last X hours + if (GetAdjustedTime() - info_old.nLastSuccess < ADDRMAN_REPLACEMENT_HOURS*(60*60)) { + erase_collision = true; + } else if (GetAdjustedTime() - info_old.nLastTry < ADDRMAN_REPLACEMENT_HOURS*(60*60)) { // attempted to connect and failed in last X hours + + // Give address at least 60 seconds to successfully connect + if (GetAdjustedTime() - info_old.nLastTry > 60) { + LogPrint(BCLog::ADDRMAN, "addrman", "Swapping %s for %s in tried table\n", info_new.ToString(), info_old.ToString()); + + // Replaces an existing address already in the tried table with the new address + Good_(info_new, false, GetAdjustedTime()); + erase_collision = true; + } + } + } else { // Collision is not actually a collision anymore + Good_(info_new, false, GetAdjustedTime()); + erase_collision = true; + } + } + + if (erase_collision) { + m_tried_collisions.erase(it++); + } else { + it++; + } + } +} + +CAddrInfo CAddrMan::SelectTriedCollision_() +{ + if (m_tried_collisions.size() == 0) return CAddrInfo(); + + std::set::iterator it = m_tried_collisions.begin(); + + // Selects a random element from m_tried_collisions + std::advance(it, GetRandInt(m_tried_collisions.size())); + int id_new = *it; + + // If id_new not found in mapInfo remove it from m_tried_collisions + if (mapInfo.count(id_new) != 1) { + m_tried_collisions.erase(it); + return CAddrInfo(); + } + + CAddrInfo& newInfo = mapInfo[id_new]; + + // which tried bucket to move the entry to + int tried_bucket = newInfo.GetTriedBucket(nKey); + int tried_bucket_pos = newInfo.GetBucketPosition(nKey, false, tried_bucket); + + int id_old = vvTried[tried_bucket][tried_bucket_pos]; + + return mapInfo[id_old]; +} diff --git a/src/addrman.h b/src/addrman.h index 38da754af..67423c6c5 100644 --- a/src/addrman.h +++ b/src/addrman.h @@ -165,6 +165,9 @@ public: //! ... in at least this many days #define ADDRMAN_MIN_FAIL_DAYS 7 +//! how recent a successful connection should be before we allow an address to be evicted from tried +#define ADDRMAN_REPLACEMENT_HOURS 4 + //! the maximum percentage of nodes to return in a getaddr call #define ADDRMAN_GETADDR_MAX_PCT 23 @@ -176,6 +179,9 @@ public: #define ADDRMAN_NEW_BUCKET_COUNT (1 << ADDRMAN_NEW_BUCKET_COUNT_LOG2) #define ADDRMAN_BUCKET_SIZE (1 << ADDRMAN_BUCKET_SIZE_LOG2) +//! the maximum number of tried addr collisions to store +#define ADDRMAN_SET_TRIED_COLLISION_SIZE 10 + /** * Stochastical (IP) address manager */ @@ -212,6 +218,9 @@ private: //! last time Good was called (memory only) int64_t nLastGood; + //! Holds addrs inserted into tried table that collide with existing entries. Test-before-evict discpline used to resolve these collisions. + std::set m_tried_collisions; + protected: //! secret key to randomize bucket select with uint256 nKey; @@ -239,7 +248,7 @@ protected: void ClearNew(int nUBucket, int nUBucketPos); //! Mark an entry "good", possibly moving it from "new" to "tried". - void Good_(const CService &addr, int64_t nTime); + void Good_(const CService &addr, bool test_before_evict, int64_t time); //! Add an entry to the "new" table. bool Add_(const CAddress &addr, const CNetAddr& source, int64_t nTimePenalty); @@ -250,6 +259,12 @@ protected: //! Select an address to connect to, if newOnly is set to true, only the new table is selected from. CAddrInfo Select_(bool newOnly); + //! See if any to-be-evicted tried table entries have been tested and if so resolve the collisions. + void ResolveCollisions_(); + + //! Return a random to-be-evicted tried table address. + CAddrInfo SelectTriedCollision_(); + //! Wraps GetRandInt to allow tests to override RandomInt and make it determinismistic. virtual int RandomInt(int nMax); @@ -537,11 +552,11 @@ public: } //! Mark an entry as accessible. - void Good(const CService &addr, int64_t nTime = GetAdjustedTime()) + void Good(const CService &addr, bool test_before_evict = true, int64_t nTime = GetAdjustedTime()) { LOCK(cs); Check(); - Good_(addr, nTime); + Good_(addr, test_before_evict, nTime); Check(); } @@ -554,6 +569,28 @@ public: Check(); } + //! See if any to-be-evicted tried table entries have been tested and if so resolve the collisions. + void ResolveCollisions() + { + LOCK(cs); + Check(); + ResolveCollisions_(); + Check(); + } + + //! Randomly select an address in tried that another address is attempting to evict. + CAddrInfo SelectTriedCollision() + { + CAddrInfo ret; + { + LOCK(cs); + Check(); + ret = SelectTriedCollision_(); + Check(); + } + return ret; + } + /** * Choose an address to connect to. */ diff --git a/src/net.cpp b/src/net.cpp index 201914685..e08ce0fd3 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -1824,11 +1824,18 @@ void CConnman::ThreadOpenConnections(const std::vector connect) } } + addrman.ResolveCollisions(); + int64_t nANow = GetAdjustedTime(); int nTries = 0; while (!interruptNet) { - CAddrInfo addr = addrman.Select(fFeeler); + CAddrInfo addr = addrman.SelectTriedCollision(); + + // SelectTriedCollision returns an invalid address if it is empty. + if (!fFeeler || !addr.IsValid()) { + addr = addrman.Select(fFeeler); + } // if we selected an invalid address, restart if (!addr.IsValid() || setConnected.count(addr.GetGroup()) || IsLocal(addr)) diff --git a/src/test/addrman_tests.cpp b/src/test/addrman_tests.cpp index b338d6d36..0d8bd9011 100644 --- a/src/test/addrman_tests.cpp +++ b/src/test/addrman_tests.cpp @@ -52,6 +52,17 @@ public: { CAddrMan::Delete(nId); } + + // Simulates connection failure so that we can test eviction of offline nodes + void SimConnFail(CService& addr) + { + int64_t nLastSuccess = 1; + Good_(addr, true, nLastSuccess); // Set last good connection in the deep past. + + bool count_failure = false; + int64_t nLastTry = GetAdjustedTime()-61; + Attempt(addr, count_failure, nLastTry); + } }; static CNetAddr ResolveIP(const char* ip) @@ -226,7 +237,7 @@ BOOST_AUTO_TEST_CASE(addrman_new_collisions) BOOST_CHECK_EQUAL(addrman.size(), 0); for (unsigned int i = 1; i < 18; i++) { - CService addr = ResolveService("250.1.1." + boost::to_string(i)); + CService addr = ResolveService("250.1.1." + std::to_string(i)); addrman.Add(CAddress(addr, NODE_NONE), source); //Test: No collision in new table yet. @@ -252,7 +263,7 @@ BOOST_AUTO_TEST_CASE(addrman_tried_collisions) BOOST_CHECK_EQUAL(addrman.size(), 0); for (unsigned int i = 1; i < 80; i++) { - CService addr = ResolveService("250.1.1." + boost::to_string(i)); + CService addr = ResolveService("250.1.1." + std::to_string(i)); addrman.Add(CAddress(addr, NODE_NONE), source); addrman.Good(CAddress(addr, NODE_NONE)); @@ -385,7 +396,7 @@ BOOST_AUTO_TEST_CASE(addrman_getaddr) for (unsigned int i = 1; i < (8 * 256); i++) { int octet1 = i % 256; int octet2 = i >> 8 % 256; - std::string strAddr = boost::to_string(octet1) + "." + boost::to_string(octet2) + ".1.23"; + std::string strAddr = std::to_string(octet1) + "." + std::to_string(octet2) + ".1.23"; CAddress addr = CAddress(ResolveService(strAddr), NODE_NONE); // Ensure that for all addrs in addrman, isTerrible == false. @@ -436,8 +447,8 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_tried_bucket) std::set buckets; for (int i = 0; i < 255; i++) { CAddrInfo infoi = CAddrInfo( - CAddress(ResolveService("250.1.1." + boost::to_string(i)), NODE_NONE), - ResolveIP("250.1.1." + boost::to_string(i))); + CAddress(ResolveService("250.1.1." + std::to_string(i)), NODE_NONE), + ResolveIP("250.1.1." + std::to_string(i))); int bucket = infoi.GetTriedBucket(nKey1); buckets.insert(bucket); } @@ -448,8 +459,8 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_tried_bucket) buckets.clear(); for (int j = 0; j < 255; j++) { CAddrInfo infoj = CAddrInfo( - CAddress(ResolveService("250." + boost::to_string(j) + ".1.1"), NODE_NONE), - ResolveIP("250." + boost::to_string(j) + ".1.1")); + CAddress(ResolveService("250." + std::to_string(j) + ".1.1"), NODE_NONE), + ResolveIP("250." + std::to_string(j) + ".1.1")); int bucket = infoj.GetTriedBucket(nKey1); buckets.insert(bucket); } @@ -488,8 +499,8 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket) std::set buckets; for (int i = 0; i < 255; i++) { CAddrInfo infoi = CAddrInfo( - CAddress(ResolveService("250.1.1." + boost::to_string(i)), NODE_NONE), - ResolveIP("250.1.1." + boost::to_string(i))); + CAddress(ResolveService("250.1.1." + std::to_string(i)), NODE_NONE), + ResolveIP("250.1.1." + std::to_string(i))); int bucket = infoi.GetNewBucket(nKey1); buckets.insert(bucket); } @@ -501,7 +512,7 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket) for (int j = 0; j < 4 * 255; j++) { CAddrInfo infoj = CAddrInfo(CAddress( ResolveService( - boost::to_string(250 + (j / 255)) + "." + boost::to_string(j % 256) + ".1.1"), NODE_NONE), + std::to_string(250 + (j / 255)) + "." + std::to_string(j % 256) + ".1.1"), NODE_NONE), ResolveIP("251.4.1.1")); int bucket = infoj.GetNewBucket(nKey1); buckets.insert(bucket); @@ -514,7 +525,7 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket) for (int p = 0; p < 255; p++) { CAddrInfo infoj = CAddrInfo( CAddress(ResolveService("250.1.1.1"), NODE_NONE), - ResolveIP("250." + boost::to_string(p) + ".1.1")); + ResolveIP("250." + std::to_string(p) + ".1.1")); int bucket = infoj.GetNewBucket(nKey1); buckets.insert(bucket); } @@ -522,4 +533,158 @@ BOOST_AUTO_TEST_CASE(caddrinfo_get_new_bucket) // than 64 buckets. BOOST_CHECK(buckets.size() > 64); } + + +BOOST_AUTO_TEST_CASE(addrman_selecttriedcollision) +{ + CAddrManTest addrman; + + // Set addrman addr placement to be deterministic. + addrman.MakeDeterministic(); + + BOOST_CHECK(addrman.size() == 0); + + // Empty addrman should return blank addrman info. + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + + // Add twenty two addresses. + CNetAddr source = ResolveIP("252.2.2.2"); + for (unsigned int i = 1; i < 23; i++) { + CService addr = ResolveService("250.1.1."+std::to_string(i)); + addrman.Add(CAddress(addr, NODE_NONE), source); + addrman.Good(addr); + + // No collisions yet. + BOOST_CHECK(addrman.size() == i); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + } + + // Ensure Good handles duplicates well. + for (unsigned int i = 1; i < 23; i++) { + CService addr = ResolveService("250.1.1."+std::to_string(i)); + addrman.Good(addr); + + BOOST_CHECK(addrman.size() == 22); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + } + +} + +BOOST_AUTO_TEST_CASE(addrman_noevict) +{ + CAddrManTest addrman; + + // Set addrman addr placement to be deterministic. + addrman.MakeDeterministic(); + + // Add twenty two addresses. + CNetAddr source = ResolveIP("252.2.2.2"); + for (unsigned int i = 1; i < 23; i++) { + CService addr = ResolveService("250.1.1."+std::to_string(i)); + addrman.Add(CAddress(addr, NODE_NONE), source); + addrman.Good(addr); + + // No collision yet. + BOOST_CHECK(addrman.size() == i); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + } + + // Collision between 23 and 19. + CService addr23 = ResolveService("250.1.1.23"); + addrman.Add(CAddress(addr23, NODE_NONE), source); + addrman.Good(addr23); + + BOOST_CHECK(addrman.size() == 23); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "250.1.1.19:0"); + + // 23 should be discarded and 19 not evicted. + addrman.ResolveCollisions(); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + + // Lets create two collisions. + for (unsigned int i = 24; i < 33; i++) { + CService addr = ResolveService("250.1.1."+std::to_string(i)); + addrman.Add(CAddress(addr, NODE_NONE), source); + addrman.Good(addr); + + BOOST_CHECK(addrman.size() == i); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + } + + // Cause a collision. + CService addr33 = ResolveService("250.1.1.33"); + addrman.Add(CAddress(addr33, NODE_NONE), source); + addrman.Good(addr33); + BOOST_CHECK(addrman.size() == 33); + + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "250.1.1.27:0"); + + // Cause a second collision. + addrman.Add(CAddress(addr23, NODE_NONE), source); + addrman.Good(addr23); + BOOST_CHECK(addrman.size() == 33); + + BOOST_CHECK(addrman.SelectTriedCollision().ToString() != "[::]:0"); + addrman.ResolveCollisions(); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); +} + +BOOST_AUTO_TEST_CASE(addrman_evictionworks) +{ + CAddrManTest addrman; + + // Set addrman addr placement to be deterministic. + addrman.MakeDeterministic(); + + BOOST_CHECK(addrman.size() == 0); + + // Empty addrman should return blank addrman info. + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + + // Add twenty two addresses. + CNetAddr source = ResolveIP("252.2.2.2"); + for (unsigned int i = 1; i < 23; i++) { + CService addr = ResolveService("250.1.1."+std::to_string(i)); + addrman.Add(CAddress(addr, NODE_NONE), source); + addrman.Good(addr); + + // No collision yet. + BOOST_CHECK(addrman.size() == i); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + } + + // Collision between 23 and 19. + CService addr = ResolveService("250.1.1.23"); + addrman.Add(CAddress(addr, NODE_NONE), source); + addrman.Good(addr); + + BOOST_CHECK(addrman.size() == 23); + CAddrInfo info = addrman.SelectTriedCollision(); + BOOST_CHECK(info.ToString() == "250.1.1.19:0"); + + // Ensure test of address fails, so that it is evicted. + addrman.SimConnFail(info); + + // Should swap 23 for 19. + addrman.ResolveCollisions(); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + + // If 23 was swapped for 19, then this should cause no collisions. + addrman.Add(CAddress(addr, NODE_NONE), source); + addrman.Good(addr); + + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); + + // If we insert 19 is should collide with 23. + CService addr19 = ResolveService("250.1.1.19"); + addrman.Add(CAddress(addr19, NODE_NONE), source); + addrman.Good(addr19); + + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "250.1.1.23:0"); + + addrman.ResolveCollisions(); + BOOST_CHECK(addrman.SelectTriedCollision().ToString() == "[::]:0"); +} + + BOOST_AUTO_TEST_SUITE_END()