From 5b83ccbb2da56737e79dcbbeae0a643a13803330 Mon Sep 17 00:00:00 2001 From: stoffu Date: Fri, 15 May 2020 10:56:23 +0900 Subject: [PATCH] daemon: guard against rare 'difficulty drift' bug with checkpoints and recalculation On startup, it checks against the difficulty checkpoints, and if any mismatch is found, recalculates all the blocks with wrong difficulties. Additionally, once a week it recalculates difficulties of blocks after the last difficulty checkpoint. --- src/blockchain_db/blockchain_db.h | 10 +++ src/blockchain_db/lmdb/db_lmdb.cpp | 38 ++++++++ src/blockchain_db/lmdb/db_lmdb.h | 2 + src/blockchain_db/testdb.h | 1 + src/checkpoints/checkpoints.cpp | 95 +++++++------------- src/checkpoints/checkpoints.h | 13 ++- src/cryptonote_core/blockchain.cpp | 115 ++++++++++++++++++++++++ src/cryptonote_core/blockchain.h | 16 ++++ src/cryptonote_core/cryptonote_core.cpp | 7 ++ src/cryptonote_core/cryptonote_core.h | 8 ++ 10 files changed, 242 insertions(+), 63 deletions(-) diff --git a/src/blockchain_db/blockchain_db.h b/src/blockchain_db/blockchain_db.h index f695cb659..f513651ed 100644 --- a/src/blockchain_db/blockchain_db.h +++ b/src/blockchain_db/blockchain_db.h @@ -1038,6 +1038,16 @@ public: */ virtual difficulty_type get_block_difficulty(const uint64_t& height) const = 0; + /** + * @brief correct blocks cumulative difficulties that were incorrectly calculated due to the 'difficulty drift' bug + * + * If the block does not exist, the subclass should throw BLOCK_DNE + * + * @param start_height the height where the drift starts + * @param new_cumulative_difficulties new cumulative difficulties to be stored + */ + virtual void correct_block_cumulative_difficulties(const uint64_t& start_height, const std::vector& new_cumulative_difficulties) = 0; + /** * @brief fetch a block's already generated coins * diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp index dc29df8ea..6f47a8118 100644 --- a/src/blockchain_db/lmdb/db_lmdb.cpp +++ b/src/blockchain_db/lmdb/db_lmdb.cpp @@ -2779,6 +2779,44 @@ difficulty_type BlockchainLMDB::get_block_difficulty(const uint64_t& height) con return diff1 - diff2; } +void BlockchainLMDB::correct_block_cumulative_difficulties(const uint64_t& start_height, const std::vector& new_cumulative_difficulties) +{ + LOG_PRINT_L3("BlockchainLMDB::" << __func__); + check_open(); + mdb_txn_cursors *m_cursors = &m_wcursors; + + int result = 0; + block_wtxn_start(); + CURSOR(block_info) + + const uint64_t bc_height = height(); + if (start_height + new_cumulative_difficulties.size() != bc_height) + { + block_wtxn_abort(); + throw0(DB_ERROR("Incorrect new_cumulative_difficulties size")); + } + + for (uint64_t height = start_height; height < bc_height; ++height) + { + MDB_val_set(key, height); + result = mdb_cursor_get(m_cur_block_info, (MDB_val *)&zerokval, &key, MDB_GET_BOTH); + if (result) + throw1(BLOCK_DNE(lmdb_error("Failed to get block info: ", result).c_str())); + + mdb_block_info bi = *(mdb_block_info*)key.mv_data; + const difficulty_type d = new_cumulative_difficulties[height - start_height]; + bi.bi_diff_hi = ((d >> 64) & 0xffffffffffffffff).convert_to(); + bi.bi_diff_lo = (d & 0xffffffffffffffff).convert_to(); + + MDB_val_set(key2, height); + MDB_val_set(val, bi); + result = mdb_cursor_put(m_cur_block_info, &key2, &val, MDB_CURRENT); + if (result) + throw0(DB_ERROR(lmdb_error("Failed to overwrite block info to db transaction: ", result).c_str())); + } + block_wtxn_stop(); +} + uint64_t BlockchainLMDB::get_block_already_generated_coins(const uint64_t& height) const { LOG_PRINT_L3("BlockchainLMDB::" << __func__); diff --git a/src/blockchain_db/lmdb/db_lmdb.h b/src/blockchain_db/lmdb/db_lmdb.h index 2dd4e7107..5abb8014f 100644 --- a/src/blockchain_db/lmdb/db_lmdb.h +++ b/src/blockchain_db/lmdb/db_lmdb.h @@ -229,6 +229,8 @@ public: virtual difficulty_type get_block_difficulty(const uint64_t& height) const; + virtual void correct_block_cumulative_difficulties(const uint64_t& start_height, const std::vector& new_cumulative_difficulties); + virtual uint64_t get_block_already_generated_coins(const uint64_t& height) const; virtual uint64_t get_block_long_term_weight(const uint64_t& height) const; diff --git a/src/blockchain_db/testdb.h b/src/blockchain_db/testdb.h index 24324bce3..92911d081 100644 --- a/src/blockchain_db/testdb.h +++ b/src/blockchain_db/testdb.h @@ -82,6 +82,7 @@ public: virtual std::vector get_block_weights(uint64_t start_height, size_t count) const override { return {}; } virtual cryptonote::difficulty_type get_block_cumulative_difficulty(const uint64_t& height) const override { return 10; } virtual cryptonote::difficulty_type get_block_difficulty(const uint64_t& height) const override { return 0; } + virtual void correct_block_cumulative_difficulties(const uint64_t& start_height, const std::vector& new_cumulative_difficulties) override {} virtual uint64_t get_block_already_generated_coins(const uint64_t& height) const override { return 10000000000; } virtual uint64_t get_block_long_term_weight(const uint64_t& height) const override { return 128; } virtual std::vector get_long_term_block_weights(uint64_t start_height, size_t count) const override { return {}; } diff --git a/src/checkpoints/checkpoints.cpp b/src/checkpoints/checkpoints.cpp index c0b787e77..32e711bb6 100644 --- a/src/checkpoints/checkpoints.cpp +++ b/src/checkpoints/checkpoints.cpp @@ -72,7 +72,7 @@ namespace cryptonote { } //--------------------------------------------------------------------------- - bool checkpoints::add_checkpoint(uint64_t height, const std::string& hash_str) + bool checkpoints::add_checkpoint(uint64_t height, const std::string& hash_str, const std::string& difficulty_str) { crypto::hash h = crypto::null_hash; bool r = epee::string_tools::hex_to_pod(hash_str, h); @@ -84,6 +84,23 @@ namespace cryptonote CHECK_AND_ASSERT_MES(h == m_points[height], false, "Checkpoint at given height already exists, and hash for new checkpoint was different!"); } m_points[height] = h; + if (!difficulty_str.empty()) + { + try + { + difficulty_type difficulty(difficulty_str); + if (m_difficulty_points.count(height)) + { + CHECK_AND_ASSERT_MES(difficulty == m_difficulty_points[height], false, "Difficulty checkpoint at given height already exists, and difficulty for new checkpoint was different!"); + } + m_difficulty_points[height] = difficulty; + } + catch (...) + { + LOG_ERROR("Failed to parse difficulty checkpoint: " << difficulty_str); + return false; + } + } return true; } //--------------------------------------------------------------------------- @@ -143,6 +160,11 @@ namespace cryptonote { return m_points; } + //--------------------------------------------------------------------------- + const std::map& checkpoints::get_difficulty_points() const + { + return m_difficulty_points; + } bool checkpoints::check_for_conflicts(const checkpoints& other) const { @@ -166,67 +188,16 @@ namespace cryptonote { return true; } - ADD_CHECKPOINT(1, "97f4ce4d7879b3bea54dcec738cd2ebb7952b4e9bb9743262310cd5fec749340"); - ADD_CHECKPOINT(10, "305472c87ff86d8afb3ec42634828462b0ed3d929fc05fa1ae668c3bee04837a"); - ADD_CHECKPOINT(100, "a92b9deae26e19322041cbc2f850fa905748ae1e5bf69b35ca90b247c5cbfc04"); - ADD_CHECKPOINT(1000, "62921e13030b29264439cafaf8320cf8aa039ee6ba7ba29c72f11b50a079269a"); - ADD_CHECKPOINT(2000, "b3e1d73e3d0243239481aa76cb075cf2428556f5dc4f2e30428ea2ba36693e97"); - ADD_CHECKPOINT(3000, "83a6e1ab394e80b8442b7b70b0e4c3a9fa0143e0ca51a33e829537ef5dd1bf13"); - ADD_CHECKPOINT(4000, "7c70722d8cb8106b4bec67e1790614cc6e98db7afd0843b96cdff6960a0e0073"); - ADD_CHECKPOINT(5000, "331ee74008e174e5fd1956f64c52793961b321a1366f7c6f7d324e8265df34f6"); - ADD_CHECKPOINT(6969, "aa7b66e8c461065139b55c29538a39c33ceda93e587f84d490ed573d80511c87"); //Hard fork to v8 - ADD_CHECKPOINT(7000, "2711bd33b107f744ad8bf98c1acefa18658780079496bd2f3a36f2e20b261f8e"); - ADD_CHECKPOINT(7500, "5975967c4624f13f058acafe7adf9355e03e8e802eeadc84ccb22ea588bc0762"); - ADD_CHECKPOINT(7900, "d9bc18cb35feb6b26bc5a19bbdbf7c852d9cc02883acb5bbce2e87d8b2c86069"); - ADD_CHECKPOINT(10000, "bc5bfbf1b26c8f976d1d792ece4c6a7e93064bec62b72f1d5beae74c3f273b3b"); - ADD_CHECKPOINT(20000, "52cc7edcb49eb02f28a653b824089a726f4050eb210263ee6f4180d388a1e5cc"); - ADD_CHECKPOINT(30000, "d22fde5dd240ade16d3250eb0aa5d1c16dc7cb51c20484e05eb274911032b3fa"); - ADD_CHECKPOINT(40000, "aee0d642322542ba069cb1c58ab2acd3560f108d4682c3dc3cb15a54d442d91f"); - ADD_CHECKPOINT(50000, "5286ac2a0f39b3aefcba363cd71f2760bd1e0d763cbc81026ebdc3f80a86541f"); - ADD_CHECKPOINT(53666, "3f43f56f66ef0c43cf2fd14d0d28fa2aae0ef8f40716773511345750770f1255"); //Hard fork to v9 - ADD_CHECKPOINT(54500, "8ed3078b389c2b44add007803d741b58d3fbed2e1ba4139bda702152d8773c9b"); - ADD_CHECKPOINT(55000, "4b662ceccefc3247edb4d654dd610b8fb496e85b88a5de43cc2bdd28171b15ff"); - ADD_CHECKPOINT(57000, "08a79f09f12bb5d230b63963356a760d51618e526cfc636047a6f3798217c177"); - ADD_CHECKPOINT(59000, "180b51ee2c5fbcd4362eb7a29df9422481310dd77d10bccdf8930724c31e007e"); - ADD_CHECKPOINT(59900, "18cc0653ef39cb304c68045dba5eb6b885f936281cd939dea04d0e6c9cd4ae2e"); - ADD_CHECKPOINT(60000, "0f02aa57a63f79f63dafed9063abe228a37cb19f00430dc3168b8a8f4ae8016c"); - ADD_CHECKPOINT(61000, "509aca8c54eb5fe44623768757b6e890ae39d512478c75f614cbff3d91809350"); - ADD_CHECKPOINT(62000, "7fe91ad256c08dbd961e04738968be22fb481093fbfa7959bde7796ccceba0e2"); - ADD_CHECKPOINT(62150, "1a7c75f8ebeda0e20eb5877181eafd7db0fc887e3fed43e0b27ab2e7bccafd10"); - ADD_CHECKPOINT(62269, "4969555d60742afb93925fd96d83ac28f45e6e3c0e583c9fb3c92d9b2100d38f"); - ADD_CHECKPOINT(62405, "4d0ae890cf9f875f231c7069508ad28dc429d14814b52db114dfab7519a27584"); - ADD_CHECKPOINT(62419, "bd8bf5ac4c4fb07ab4d0d492bd1699def5c095ab6943ad3b63a89d1d8b1ce748"); - ADD_CHECKPOINT(62425, "41a922dba6f3906871b2ccaf31ec9c91033470c503959093dae796deda8940ea"); - ADD_CHECKPOINT(62479, "a2e8ff4205ba2980eb70921b0b21b5fc656ee273664ea94b860c68ca069b60dd"); - ADD_CHECKPOINT(62503, "25fa115962988b4b8f8cfd22744a3e653b22ead8c8468e64caf334fc75a97d08"); - ADD_CHECKPOINT(62550, "bde522a8a81c392c98c979434aa1dd9d20b4ca52230ba6ae0362872757808a48"); - ADD_CHECKPOINT(62629, "8368e1ce1d421f1fc969364558433e2b2363d0ffcb5f2d946633095e3e6734f5"); - ADD_CHECKPOINT(62720, "f871cddd75951e2fe24c282d2bd28396fc922ea519b354ace992a0162cb333ff"); - ADD_CHECKPOINT(62733, "8331dbeeaf23173d2235a062373a437befadb6492cceb7640127bf18653a9e61"); - ADD_CHECKPOINT(62877, "62d44adc05d7d4fd9d15239c5575612207beab0bcf2da49158bf89e365441ca1"); - ADD_CHECKPOINT(63469, "4e33a9343fc5b86661ec0affaeb5b5a065290602c02d817337e4a979fe5747d8"); //Hard fork to v10 - ADD_CHECKPOINT(69800, "5c65428a664738bc083d1ccd6a1b5ff4305f98e7633f44033816801429b33ce1"); - ADD_CHECKPOINT(75000, "e93492f79b5344e7edb31537ee65b3e908bf71110cff8188c0c62fefc015d342"); - ADD_CHECKPOINT(79500, "9bbfd6f2257ce9084de30179944b7695c9b918c9c03a8a63306ab6c5828ff857"); - ADD_CHECKPOINT(80920, "8fca818344f97ea3912557cbd8be659cf6a5bc1203514c27338e234251d72dfb"); - ADD_CHECKPOINT(81769, "41db9fef8d0ccfa78b570ee9525d4f55de77b510c3ae4b08a1d51b9aec9ade1d"); //Hard fork to v11 - ADD_CHECKPOINT(82069, "fdea800d23d0b2eea19dec8af31e453e883e8315c97e25c8bb3e88ca164f8369"); //Hard fork to v12 - ADD_CHECKPOINT(85000, "31d62ab75470b15aedee6674b78767b53f10951786e991c26035743c267b247a"); - ADD_CHECKPOINT(87000, "a788e5a7233ca2198ad6446ddc454b05d578e72253ed2bbca969527230f6eec2"); - ADD_CHECKPOINT(88200, "50bb43d5d563524d6b9f308a2483b80934bab2ab5250757558318834476f1cfb"); - ADD_CHECKPOINT(100000, "0c1f3bec32fe4ac9bd4b6ce1f4dfc52824f0947d756c9a1a453252c9423071f5"); - ADD_CHECKPOINT(111450, "d6eadc95607765b36afd8b9148eac20eb101632021348cd34371fc1d8b67f6b6"); - ADD_CHECKPOINT(114969, "b48245956b87f243048fd61021f4b3e5443e57eee7ff8ba4762d18926e80b80c"); //Hard fork to v13 - ADD_CHECKPOINT(114980, "3a96963b93154889bd7d59c8a60cf8005e864b930627616e51a4ad11cd9a3d50"); - ADD_CHECKPOINT(115257, "338e056551087fe23d6c4b4280244bc5362b004716d85ec799a775f190f9fea9"); //Hard fork to v14 - ADD_CHECKPOINT(118500, "2ef1cd0c68f1b8e1acf384109431b6377dbdbd6705964be17b7358c47ea07447"); - ADD_CHECKPOINT(157400, "44445d1fcc845b4d6f8e7730c50af64c09031003d584cdeaa04d6523e0acc049"); - ADD_CHECKPOINT(160777, "9496690579af21f38f00e67e11c2e85a15912fe4f412aad33d1162be1579e755"); //Hard fork to v15 - ADD_CHECKPOINT(194444, "0aa7ea6ade2ee8f5a525a079c53888fac415826ee8d1e8c92caa52629773db35"); - ADD_CHECKPOINT(200500, "1e5c7af11e19a94f334576d79fe0179ff493ce378701f3f810b674db2760c228"); - ADD_CHECKPOINT(211300, "f712b6dc0dfe896d18c5ca9097144d05ef8810b11277663638c0963d96ea172c"); - ADD_CHECKPOINT(223800, "878d805ce24368a48c4bd36283f3c53510e86b09511ec6770fbaca8f1fd3c55b"); - + ADD_CHECKPOINT2(1, "97f4ce4d7879b3bea54dcec738cd2ebb7952b4e9bb9743262310cd5fec749340", "0x2"); + ADD_CHECKPOINT2(6969, "aa7b66e8c461065139b55c29538a39c33ceda93e587f84d490ed573d80511c87", "0x118eef693fd"); //Hard fork to v8 + ADD_CHECKPOINT2(53666, "3f43f56f66ef0c43cf2fd14d0d28fa2aae0ef8f40716773511345750770f1255", "0xb677d6405ae"); //Hard fork to v9 + ADD_CHECKPOINT2(63469, "4e33a9343fc5b86661ec0affaeb5b5a065290602c02d817337e4a979fe5747d8", "0xe7cd9819062"); //Hard fork to v10 + ADD_CHECKPOINT2(81769, "41db9fef8d0ccfa78b570ee9525d4f55de77b510c3ae4b08a1d51b9aec9ade1d", "0x150066455b88"); //Hard fork to v11 + ADD_CHECKPOINT2(82069, "fdea800d23d0b2eea19dec8af31e453e883e8315c97e25c8bb3e88ca164f8369", "0x15079b5fdaa8"); //Hard fork to v12 + ADD_CHECKPOINT2(114969, "b48245956b87f243048fd61021f4b3e5443e57eee7ff8ba4762d18926e80b80c", "0x1ca552b3ec68"); //Hard fork to v13 + ADD_CHECKPOINT2(115257, "338e056551087fe23d6c4b4280244bc5362b004716d85ec799a775f190f9fea9", "0x1cb25f5d4628"); //Hard fork to v14 + ADD_CHECKPOINT2(160777, "9496690579af21f38f00e67e11c2e85a15912fe4f412aad33d1162be1579e755", "0x5376eaa196a8"); //Hard fork to v15 + ADD_CHECKPOINT2(230200, "0ebb018c452fa84997f573937db67ef3946a857ee57cd40fa51ffe368896c666", "0xbcc1409c7268"); return true; } diff --git a/src/checkpoints/checkpoints.h b/src/checkpoints/checkpoints.h index cb6e93972..029c50548 100644 --- a/src/checkpoints/checkpoints.h +++ b/src/checkpoints/checkpoints.h @@ -33,8 +33,10 @@ #include "misc_log_ex.h" #include "crypto/hash.h" #include "cryptonote_config.h" +#include "cryptonote_basic/difficulty.h" #define ADD_CHECKPOINT(h, hash) CHECK_AND_ASSERT(add_checkpoint(h, hash), false); +#define ADD_CHECKPOINT2(h, hash, difficulty) CHECK_AND_ASSERT(add_checkpoint(h, hash, difficulty), false); #define JSON_HASH_FILE_NAME "checkpoints.json" @@ -61,12 +63,13 @@ namespace cryptonote * * @param height the height of the block the checkpoint is for * @param hash_str the hash of the block, as a string + * @param difficulty_str the cumulative difficulty of the block, as a string (optional) * * @return false if parsing the hash fails, or if the height is a duplicate * AND the existing checkpoint hash does not match the new one, * otherwise returns true */ - bool add_checkpoint(uint64_t height, const std::string& hash_str); + bool add_checkpoint(uint64_t height, const std::string& hash_str, const std::string& difficulty_str = ""); /** * @brief checks if there is a checkpoint in the future @@ -133,6 +136,13 @@ namespace cryptonote */ const std::map& get_points() const; + /** + * @brief gets the difficulty checkpoints container + * + * @return a const reference to the difficulty checkpoints container + */ + const std::map& get_difficulty_points() const; + /** * @brief checks if our checkpoints container conflicts with another * @@ -187,6 +197,7 @@ namespace cryptonote private: std::map m_points; //!< the checkpoints container + std::map m_difficulty_points; //!< the difficulty checkpoints container }; } diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp index 8bbde6fd2..2b3e2b71f 100644 --- a/src/cryptonote_core/blockchain.cpp +++ b/src/cryptonote_core/blockchain.cpp @@ -32,6 +32,7 @@ #include #include #include +#include #include "include_base_utils.h" #include "cryptonote_basic/cryptonote_basic_impl.h" @@ -440,6 +441,15 @@ bool Blockchain::init(BlockchainDB* db, const network_type nettype, bool offline m_long_term_block_weights_cache_rolling_median = epee::misc_utils::rolling_median_t(m_long_term_block_weights_window); } + bool difficulty_ok; + uint64_t difficulty_recalc_height; + std::tie(difficulty_ok, difficulty_recalc_height) = check_difficulty_checkpoints(); + if (!difficulty_ok) + { + MERROR("Difficulty drift detected!"); + recalculate_difficulties(difficulty_recalc_height); + } + { db_txn_guard txn_guard(m_db, m_db->is_read_only()); if (!update_next_cumulative_weight_limit()) @@ -984,6 +994,111 @@ start: return diff; } //------------------------------------------------------------------ +std::pair Blockchain::check_difficulty_checkpoints() const +{ + uint64_t res = 0; + for (const std::pair& i : m_checkpoints.get_difficulty_points()) + { + if (i.first >= m_db->height()) + break; + if (m_db->get_block_cumulative_difficulty(i.first) != i.second) + return {false, res}; + res = i.first; + } + return {true, res}; +} +//------------------------------------------------------------------ +size_t Blockchain::recalculate_difficulties(boost::optional start_height_opt) +{ + if (m_fixed_difficulty) + { + return 0; + } + LOG_PRINT_L3("Blockchain::" << __func__); + CRITICAL_REGION_LOCAL(m_blockchain_lock); + + const uint64_t start_height = start_height_opt ? *start_height_opt : check_difficulty_checkpoints().second; + const uint64_t top_height = m_db->height() - 1; + MGINFO("Recalculating difficulties from height " << start_height << " to height " << top_height); + + std::vector timestamps; + std::vector difficulties; + timestamps.reserve(DIFFICULTY_BLOCKS_COUNT + 1); + difficulties.reserve(DIFFICULTY_BLOCKS_COUNT + 1); + if (start_height > 1) + { + for (uint64_t i = 0; i < DIFFICULTY_BLOCKS_COUNT; ++i) + { + uint64_t height = start_height - 1 - i; + if (height == 0) + break; + timestamps.insert(timestamps.begin(), m_db->get_block_timestamp(height)); + difficulties.insert(difficulties.begin(), m_db->get_block_cumulative_difficulty(height)); + } + } + difficulty_type last_cum_diff = start_height <= 1 ? start_height : difficulties.back(); + uint64_t drift_start_height = 0; + std::vector new_cumulative_difficulties; + for (uint64_t height = start_height; height <= top_height; ++height) + { + size_t target = get_ideal_hard_fork_version(height) < 2 ? DIFFICULTY_TARGET_V1 : DIFFICULTY_TARGET_V2; + difficulty_type recalculated_diff = next_difficulty(timestamps, difficulties, target); + + boost::multiprecision::uint256_t recalculated_cum_diff_256 = boost::multiprecision::uint256_t(recalculated_diff) + last_cum_diff; + CHECK_AND_ASSERT_THROW_MES(recalculated_cum_diff_256 <= std::numeric_limits::max(), "Difficulty overflow!"); + difficulty_type recalculated_cum_diff = recalculated_cum_diff_256.convert_to(); + + if (drift_start_height == 0) + { + difficulty_type existing_cum_diff = m_db->get_block_cumulative_difficulty(height); + if (recalculated_cum_diff != existing_cum_diff) + { + drift_start_height = height; + new_cumulative_difficulties.reserve(top_height + 1 - height); + LOG_ERROR("Difficulty drift found at height:" << height << ", hash:" << m_db->get_block_hash_from_height(height) << ", existing:" << existing_cum_diff << ", recalculated:" << recalculated_cum_diff); + } + } + if (drift_start_height > 0) + { + new_cumulative_difficulties.push_back(recalculated_cum_diff); + if (height % 100000 == 0) + LOG_ERROR(boost::format("%llu / %llu (%.1f%%)") % height % top_height % (100 * (height - drift_start_height) / float(top_height - drift_start_height))); + } + + if (height > 0) + { + timestamps.push_back(m_db->get_block_timestamp(height)); + difficulties.push_back(recalculated_cum_diff); + } + if (timestamps.size() > DIFFICULTY_BLOCKS_COUNT) + { + CHECK_AND_ASSERT_THROW_MES(timestamps.size() == DIFFICULTY_BLOCKS_COUNT + 1, "Wrong timestamps size: " << timestamps.size()); + timestamps.erase(timestamps.begin()); + difficulties.erase(difficulties.begin()); + } + last_cum_diff = recalculated_cum_diff; + } + + if (drift_start_height > 0) + { + LOG_ERROR("Writing to the DB..."); + try + { + m_db->correct_block_cumulative_difficulties(drift_start_height, new_cumulative_difficulties); + } + catch (const std::exception& e) + { + LOG_ERROR("Error correcting cumulative difficulties from height " << drift_start_height << ", what = " << e.what()); + } + LOG_ERROR("Corrected difficulties for " << new_cumulative_difficulties.size() << " blocks"); + // clear cache + m_difficulty_for_next_block_top_hash = crypto::null_hash; + m_timestamps_and_difficulties_height = 0; + } + + return new_cumulative_difficulties.size(); +} +//------------------------------------------------------------------ std::vector Blockchain::get_last_block_timestamps(unsigned int blocks) const { CRITICAL_REGION_LOCAL(m_blockchain_lock); diff --git a/src/cryptonote_core/blockchain.h b/src/cryptonote_core/blockchain.h index 966e98f7e..fb7e5c4f8 100644 --- a/src/cryptonote_core/blockchain.h +++ b/src/cryptonote_core/blockchain.h @@ -309,6 +309,22 @@ namespace cryptonote */ difficulty_type get_difficulty_for_next_block(); + /** + * @brief check currently stored difficulties against difficulty checkpoints + * + * @return {flag, height} flag: true if all difficulty checkpoints pass, height: the last checkpoint height before the difficulty drift bug starts + */ + std::pair check_difficulty_checkpoints() const; + + /** + * @brief recalculate difficulties for blocks after the last difficulty checkpoints to circumvent the annoying 'difficulty drift' bug + * + * @param start_height: if omitted, starts recalculation from the last difficulty checkpoint + * + * @return number of blocks whose difficulties got corrected + */ + size_t recalculate_difficulties(boost::optional start_height = boost::none); + /** * @brief adds a block to the blockchain * diff --git a/src/cryptonote_core/cryptonote_core.cpp b/src/cryptonote_core/cryptonote_core.cpp index 12e46571a..4b8d6cbcc 100644 --- a/src/cryptonote_core/cryptonote_core.cpp +++ b/src/cryptonote_core/cryptonote_core.cpp @@ -1726,6 +1726,7 @@ namespace cryptonote m_check_disk_space_interval.do_call(boost::bind(&core::check_disk_space, this)); m_block_rate_interval.do_call(boost::bind(&core::check_block_rate, this)); m_blockchain_pruning_interval.do_call(boost::bind(&core::update_blockchain_pruning, this)); + m_diff_recalc_interval.do_call(boost::bind(&core::recalculate_difficulties, this)); m_miner.on_idle(); m_mempool.on_idle(); return true; @@ -1964,6 +1965,12 @@ namespace cryptonote return true; } //----------------------------------------------------------------------------------------------- + bool core::recalculate_difficulties() + { + m_blockchain_storage.recalculate_difficulties(); + return true; + } + //----------------------------------------------------------------------------------------------- void core::flush_bad_txs_cache() { bad_semantics_txes_lock.lock(); diff --git a/src/cryptonote_core/cryptonote_core.h b/src/cryptonote_core/cryptonote_core.h index 472204119..6a9ffda92 100644 --- a/src/cryptonote_core/cryptonote_core.h +++ b/src/cryptonote_core/cryptonote_core.h @@ -1028,6 +1028,13 @@ namespace cryptonote */ bool check_block_rate(); + /** + * @brief recalculate difficulties after the last difficulty checklpoint to circumvent the annoying 'difficulty drift' bug + * + * @return true + */ + bool recalculate_difficulties(); + bool m_test_drop_download = true; //!< whether or not to drop incoming blocks (for testing) uint64_t m_test_drop_download_height = 0; //!< height under which to drop incoming blocks, if doing so @@ -1053,6 +1060,7 @@ namespace cryptonote epee::math_helper::once_a_time_seconds<60*10, true> m_check_disk_space_interval; //!< interval for checking for disk space epee::math_helper::once_a_time_seconds<90, false> m_block_rate_interval; //!< interval for checking block rate epee::math_helper::once_a_time_seconds<60*60*5, true> m_blockchain_pruning_interval; //!< interval for incremental blockchain pruning + epee::math_helper::once_a_time_seconds<60*60*24*7, false> m_diff_recalc_interval; //!< interval for recalculating difficulties std::atomic m_starter_message_showed; //!< has the "daemon will sync now" message been shown?