diff --git a/src/cryptonote_basic/difficulty.cpp b/src/cryptonote_basic/difficulty.cpp index 796bd5a7f..fbd97df30 100644 --- a/src/cryptonote_basic/difficulty.cpp +++ b/src/cryptonote_basic/difficulty.cpp @@ -284,4 +284,43 @@ namespace cryptonote { return static_cast(next_D); } } + + // LWMA-3 difficulty algorithm + // Copyright (c) 2017-2018 Zawy, MIT License + difficulty_type next_difficulty_v4(std::vector timestamps, std::vector cumulative_difficulties, size_t height) { + + uint64_t T = DIFFICULTY_TARGET_V2; + uint64_t N = DIFFICULTY_WINDOW_V2; + uint64_t L(0), ST, sum_3_ST(0), next_D, prev_D, this_timestamp, previous_timestamp; + + assert(timestamps.size() == cumulative_difficulties.size() && timestamps.size() <= N+1 ); + + if ( height == DIFFICULTY_HEIGHT_V2 ){ + return static_cast(DIFFICULTY_GUESS); + } + + previous_timestamp = timestamps[0]; + for ( uint64_t i = 1; i <= N; i++) { + if ( timestamps[i] > previous_timestamp ) { + this_timestamp = timestamps[i]; + } else { this_timestamp = previous_timestamp+1; } + ST = std::min(6*T ,this_timestamp - previous_timestamp); + previous_timestamp = this_timestamp; + L += ST * i ; + if ( i > N-3 ) { sum_3_ST += ST; } + } + + next_D = ((cumulative_difficulties[N] - cumulative_difficulties[0])*T*(N+1)*99)/(100*2*L); + prev_D = cumulative_difficulties[N] - cumulative_difficulties[N-1]; + next_D = std::max((prev_D*67)/100, std::min(next_D, (prev_D*150)/100)); + + if ( sum_3_ST < (8*T)/10) { next_D = std::max(next_D,(prev_D*108)/100); } + + if ( next_D < DIFFICULTY_MINIMUM ) { + return static_cast(DIFFICULTY_MINIMUM); + } + else { + return static_cast(next_D); + } + } } diff --git a/src/cryptonote_basic/difficulty.h b/src/cryptonote_basic/difficulty.h index 247896e10..550b4c164 100644 --- a/src/cryptonote_basic/difficulty.h +++ b/src/cryptonote_basic/difficulty.h @@ -55,4 +55,5 @@ namespace cryptonote difficulty_type next_difficulty(std::vector timestamps, std::vector cumulative_difficulties, size_t target_seconds); difficulty_type next_difficulty_v2(std::vector timestamps, std::vector cumulative_difficulties, size_t target_seconds); difficulty_type next_difficulty_v3(std::vector timestamps, std::vector cumulative_difficulties, size_t height); + difficulty_type next_difficulty_v4(std::vector timestamps, std::vector cumulative_difficulties, size_t height); } diff --git a/src/cryptonote_config.h b/src/cryptonote_config.h index 9d611b43d..bf446a81f 100755 --- a/src/cryptonote_config.h +++ b/src/cryptonote_config.h @@ -48,6 +48,7 @@ #define CRYPTONOTE_BLOCK_FUTURE_TIME_LIMIT 60*60*2 #define CRYPTONOTE_DEFAULT_TX_SPENDABLE_AGE 4 +#define BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW_V2 11 #define BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW 60 // MONEY_SUPPLY - total number coins to be generated @@ -82,6 +83,7 @@ #define DIFFICULTY_BLOCKS_COUNT_V2 DIFFICULTY_WINDOW_V2 + 1 // added +1 to make N=N #define DIFFICULTY_BLOCKS_COUNT DIFFICULTY_WINDOW + DIFFICULTY_LAG #define DIFFICULTY_HEIGHT 53666 // v9 fork height +#define DIFFICULTY_HEIGHT_V2 777777 // v10 fork height #define DIFFICULTY_GUESS 40000000 // difficulty at fork 40m #define DIFFICULTY_MINIMUM 25000000 // minimum difficulty set to 25m diff --git a/src/cryptonote_core/blockchain.cpp b/src/cryptonote_core/blockchain.cpp index d762d3dfb..f5c68c64c 100755 --- a/src/cryptonote_core/blockchain.cpp +++ b/src/cryptonote_core/blockchain.cpp @@ -838,8 +838,11 @@ difficulty_type Blockchain::get_difficulty_for_next_block() else if (version == 8) { return next_difficulty_v2(timestamps, difficulties, target); } - else { + else if (version == 9) { return next_difficulty_v3(timestamps, difficulties, height); + } + else { + return next_difficulty_v4(timestamps, difficulties, height); } } //------------------------------------------------------------------ @@ -1056,9 +1059,12 @@ difficulty_type Blockchain::get_next_difficulty_for_alternative_chain(const std: } else if (version == 8) { return next_difficulty_v2(timestamps, cumulative_difficulties, target); - } + } + else if (version == 9) { + return next_difficulty_v2(timestamps, cumulative_difficulties, height); + } else { - return next_difficulty_v3(timestamps, cumulative_difficulties, height); + return next_difficulty_v4(timestamps, cumulative_difficulties, height); } } @@ -1350,12 +1356,13 @@ bool Blockchain::create_block_template(block& b, const account_public_address& m bool Blockchain::complete_timestamps_vector(uint64_t start_top_height, std::vector& timestamps) { LOG_PRINT_L3("Blockchain::" << __func__); - - if(timestamps.size() >= BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW) + const uint8_t hf_version = m_hardfork->get_current_version(); + size_t blockchain_timestamp_check_window = hf_version >= 10 ? BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW_V2 : BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW; + if(timestamps.size() >= blockchain_timestamp_check_window) return true; CRITICAL_REGION_LOCAL(m_blockchain_lock); - size_t need_elements = BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW - timestamps.size(); + size_t need_elements = blockchain_timestamp_check_window - timestamps.size(); CHECK_AND_ASSERT_MES(start_top_height < m_db->height(), false, "internal error: passed start_height not < " << " m_db->height() -- " << start_top_height << " >= " << m_db->height()); size_t stop_offset = start_top_height > need_elements ? start_top_height - need_elements : 0; while (start_top_height != stop_offset) @@ -3203,10 +3210,12 @@ bool Blockchain::check_block_timestamp(std::vector& timestamps, const { LOG_PRINT_L3("Blockchain::" << __func__); median_ts = epee::misc_utils::median(timestamps); + const uint8_t hf_version = m_hardfork->get_current_version(); + size_t blockchain_timestamp_check_window = hf_version >= 10 ? BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW_V2 : BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW; if(b.timestamp < median_ts) { - MERROR_VER("Timestamp of block with id: " << get_block_hash(b) << ", " << b.timestamp << ", less than median of last " << BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW << " blocks, " << median_ts); + MERROR_VER("Timestamp of block with id: " << get_block_hash(b) << ", " << b.timestamp << ", less than median of last " << blockchain_timestamp_check_window << " blocks, " << median_ts); return false; } @@ -3224,6 +3233,8 @@ bool Blockchain::check_block_timestamp(const block& b, uint64_t& median_ts) cons { LOG_PRINT_L3("Blockchain::" << __func__); uint64_t cryptonote_block_future_time_limit = get_current_hard_fork_version() >= 8 ? CRYPTONOTE_BLOCK_FUTURE_TIME_LIMIT_V2 : CRYPTONOTE_BLOCK_FUTURE_TIME_LIMIT; + const uint8_t hf_version = m_hardfork->get_current_version(); + size_t blockchain_timestamp_check_window = hf_version >= 10 ? BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW_V2 : BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW; if(b.timestamp > get_adjusted_time() + cryptonote_block_future_time_limit) { MERROR_VER("Timestamp of block with id: " << get_block_hash(b) << ", " << b.timestamp << ", bigger than adjusted time + 10 minutes"); @@ -3231,7 +3242,7 @@ bool Blockchain::check_block_timestamp(const block& b, uint64_t& median_ts) cons } // if not enough blocks, no proper median yet, return true - if(m_db->height() < BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW) + if(m_db->height() < blockchain_timestamp_check_window) { return true; } @@ -3240,7 +3251,7 @@ bool Blockchain::check_block_timestamp(const block& b, uint64_t& median_ts) cons auto h = m_db->height(); // need most recent 60 blocks, get index of first of those - size_t offset = h - BLOCKCHAIN_TIMESTAMP_CHECK_WINDOW; + size_t offset = h - blockchain_timestamp_check_window; for(;offset < h; ++offset) { timestamps.push_back(m_db->get_block_timestamp(offset));