From c6bb201a07d84e195be901acda2fcd0b886bf66f Mon Sep 17 00:00:00 2001 From: Thomas Winget Date: Thu, 24 Mar 2016 20:03:02 -0400 Subject: [PATCH] Transaction pool documentation (and some cleanup) tx_pool.h doxygen documentation completed. Many notes made on areas for improvement, be that functionality or code clarity. Commented code and unused code removed. --- src/cryptonote_core/tx_pool.cpp | 30 ++- src/cryptonote_core/tx_pool.h | 418 ++++++++++++++++++++++++++------ 2 files changed, 373 insertions(+), 75 deletions(-) diff --git a/src/cryptonote_core/tx_pool.cpp b/src/cryptonote_core/tx_pool.cpp index 5d67acdd..183c39d9 100644 --- a/src/cryptonote_core/tx_pool.cpp +++ b/src/cryptonote_core/tx_pool.cpp @@ -54,6 +54,9 @@ namespace cryptonote { namespace { + //FIXME: constants such as these should at least be in the header, + // but probably somewhere more accessible to the rest of the + // codebase. size_t const TRANSACTION_SIZE_LIMIT_V1 = (((CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V1 * 125) / 100) - CRYPTONOTE_COINBASE_BLOB_RESERVED_SIZE); size_t const TRANSACTION_SIZE_LIMIT_V2 = (((CRYPTONOTE_BLOCK_GRANTED_FULL_REWARD_ZONE_V2 * 125) / 100) - CRYPTONOTE_COINBASE_BLOB_RESERVED_SIZE); time_t const MIN_RELAY_TIME = (60 * 5); // only start re-relaying transactions after that many seconds @@ -116,11 +119,12 @@ namespace cryptonote return false; } + // fee per kilobyte, size rounded up. uint64_t fee = inputs_amount - outputs_amount; uint64_t needed_fee = blob_size / 1024; needed_fee += (blob_size % 1024) ? 1 : 0; needed_fee *= FEE_PER_KB; - if (!kept_by_block && fee < needed_fee /*&& fee < MINING_ALLOWED_LEGACY_FEE*/) + if (!kept_by_block && fee < needed_fee) { LOG_PRINT_L1("transaction fee is not enough: " << print_money(fee) << ", minimum fee: " << print_money(needed_fee)); tvc.m_verifivation_failed = true; @@ -135,7 +139,9 @@ namespace cryptonote return false; } - //check key images for transaction if it is not kept by block + // if the transaction came from a block popped from the chain, + // don't check if we have its key images as spent. + // TODO: Investigate why not? if(!kept_by_block) { if(have_tx_keyimges_as_spent(tx)) @@ -163,9 +169,10 @@ namespace cryptonote CRITICAL_REGION_LOCAL(m_transactions_lock); if(!ch_inp_res) { + // if the transaction was valid before (kept_by_block), then it + // may become valid again, so ignore the failed inputs check. if(kept_by_block) { - //anyway add this transaction to pool, because it related to block auto txd_p = m_transactions.insert(transactions_container::value_type(id, tx_details())); CHECK_AND_ASSERT_MES(txd_p.second, false, "transaction already exists at inserting in memory pool"); txd_p.first->second.blob_size = blob_size; @@ -207,13 +214,14 @@ namespace cryptonote tvc.m_should_be_relayed = true; } + // assume failure during verification steps until success is certain tvc.m_verifivation_failed = true; - //update image_keys container, here should everything goes ok. + BOOST_FOREACH(const auto& in, tx.vin) { CHECKED_GET_SPECIFIC_VARIANT(in, const txin_to_key, txin, false); std::unordered_set& kei_image_set = m_spent_key_images[txin.k_image]; - CHECK_AND_ASSERT_MES(kept_by_block || kei_image_set.size() == 0, false, "internal error: keeped_by_block=" << kept_by_block + CHECK_AND_ASSERT_MES(kept_by_block || kei_image_set.size() == 0, false, "internal error: kept_by_block=" << kept_by_block << ", kei_image_set.size()=" << kei_image_set.size() << ENDL << "txin.k_image=" << txin.k_image << ENDL << "tx_id=" << id ); auto ins_res = kei_image_set.insert(id); @@ -223,7 +231,7 @@ namespace cryptonote tvc.m_verifivation_failed = false; m_txs_by_fee.emplace((double)blob_size / fee, id); - //succeed + return true; } //--------------------------------------------------------------------------------- @@ -235,6 +243,9 @@ namespace cryptonote return add_tx(tx, h, blob_size, tvc, keeped_by_block, relayed, version); } //--------------------------------------------------------------------------------- + //FIXME: Can return early before removal of all of the key images. + // At the least, need to make sure that a false return here + // is treated properly. Should probably not return early, however. bool tx_memory_pool::remove_transaction_keyimages(const transaction& tx) { CRITICAL_REGION_LOCAL(m_transactions_lock); @@ -301,7 +312,7 @@ namespace cryptonote ); } //--------------------------------------------------------------------------------- - //proper tx_pool handling courtesy of CryptoZoidberg and Boolberry + //TODO: investigate whether boolean return is appropriate bool tx_memory_pool::remove_stuck_transactions() { CRITICAL_REGION_LOCAL(m_transactions_lock); @@ -332,6 +343,7 @@ namespace cryptonote return true; } //--------------------------------------------------------------------------------- + //TODO: investigate whether boolean return is appropriate bool tx_memory_pool::get_relayable_transactions(std::list> &txs) const { CRITICAL_REGION_LOCAL(m_transactions_lock); @@ -380,6 +392,7 @@ namespace cryptonote txs.push_back(tx_vt.second.tx); } //------------------------------------------------------------------ + //TODO: investigate whether boolean return is appropriate bool tx_memory_pool::get_transactions_and_spent_keys_info(std::vector& tx_infos, std::vector& key_image_infos) const { CRITICAL_REGION_LOCAL(m_transactions_lock); @@ -556,6 +569,7 @@ namespace cryptonote return ss.str(); } //--------------------------------------------------------------------------------- + //TODO: investigate whether boolean return is appropriate bool tx_memory_pool::fill_block_template(block &bl, size_t median_size, uint64_t already_generated_coins, size_t &total_size, uint64_t &fee) { // Warning: This function takes already_generated_ @@ -646,6 +660,7 @@ namespace cryptonote return n_removed; } //--------------------------------------------------------------------------------- + //TODO: investigate whether only ever returning true is correct bool tx_memory_pool::init(const std::string& config_folder) { CRITICAL_REGION_LOCAL(m_transactions_lock); @@ -679,6 +694,7 @@ namespace cryptonote } //--------------------------------------------------------------------------------- + //TODO: investigate whether only ever returning true is correct bool tx_memory_pool::deinit() { if (m_config_folder.empty()) diff --git a/src/cryptonote_core/tx_pool.h b/src/cryptonote_core/tx_pool.h index 71febcab..0ecf9008 100644 --- a/src/cryptonote_core/tx_pool.h +++ b/src/cryptonote_core/tx_pool.h @@ -57,7 +57,9 @@ namespace cryptonote /* */ /************************************************************************/ + //! pair of for organization typedef std::pair tx_by_fee_entry; + class txCompare { public: @@ -71,47 +73,255 @@ namespace cryptonote } }; + //! container for sorting transactions by fee per unit size typedef std::set sorted_tx_container; + /** + * @brief Transaction pool, handles transactions which are not part of a block + * + * This class handles all transactions which have been received, but not as + * part of a block. + * + * This handling includes: + * storing the transactions + * organizing the transactions by fee per size + * taking/giving transactions to and from various other components + * saving the transactions to disk on shutdown + * helping create a new block template by choosing transactions for it + * + */ class tx_memory_pool: boost::noncopyable { public: #if BLOCKCHAIN_DB == DB_LMDB + /** + * @brief Constructor + * + * @param bchs a Blockchain class instance, for getting chain info + */ tx_memory_pool(Blockchain& bchs); #else tx_memory_pool(blockchain_storage& bchs); #endif - bool add_tx(const transaction &tx, const crypto::hash &id, size_t blob_size, tx_verification_context& tvc, bool keeped_by_block, bool relayed, uint8_t version); - bool add_tx(const transaction &tx, tx_verification_context& tvc, bool keeped_by_block, bool relayed, uint8_t version); - //gets tx and remove it from pool + + + /** + * @copydoc add_tx(const transaction&, tx_verification_context&, bool, bool, uint8_t) + * + * @param id the transaction's hash + * @param blob_size the transaction's size + */ + bool add_tx(const transaction &tx, const crypto::hash &id, size_t blob_size, tx_verification_context& tvc, bool kept_by_block, bool relayed, uint8_t version); + + /** + * @brief add a transaction to the transaction pool + * + * Most likely the transaction will come from the network, but it is + * also possible for transactions to come from popped blocks during + * a reorg, or from local clients creating a transaction and + * submitting it to the network + * + * @param tx the transaction to be added + * @param tvc return-by-reference status about the transaction verification + * @param kept_by_block has this transaction been in a block? + * @param relayed was this transaction from the network or a local client? + * @param version the version used to create the transaction + * + * @return true if the transaction passes validations, otherwise false + */ + bool add_tx(const transaction &tx, tx_verification_context& tvc, bool kept_by_block, bool relayed, uint8_t version); + + /** + * @brief takes a transaction with the given hash from the pool + * + * @param id the hash of the transaction + * @param tx return-by-reference the transaction taken + * @param blob_size return-by-reference the transaction's size + * @param fee the transaction fee + * @param relayed return-by-reference was transaction relayed to us by the network? + * + * @return true unless the transaction cannot be found in the pool + */ bool take_tx(const crypto::hash &id, transaction &tx, size_t& blob_size, uint64_t& fee, bool &relayed); + /** + * @brief checks if the pool has a transaction with the given hash + * + * @param id the hash to look for + * + * @return true if the transaction is in the pool, otherwise false + */ bool have_tx(const crypto::hash &id) const; + + /** + * @brief action to take when notified of a block added to the blockchain + * + * Currently does nothing + * + * @param new_block_height the height of the blockchain after the change + * @param top_block_id the hash of the new top block + * + * @return true + */ bool on_blockchain_inc(uint64_t new_block_height, const crypto::hash& top_block_id); + + /** + * @brief action to take when notified of a block removed from the blockchain + * + * Currently does nothing + * + * @param new_block_height the height of the blockchain after the change + * @param top_block_id the hash of the new top block + * + * @return true + */ bool on_blockchain_dec(uint64_t new_block_height, const crypto::hash& top_block_id); + + /** + * @brief action to take periodically + * + * Currently checks transaction pool for stale ("stuck") transactions + */ void on_idle(); + /** + * @brief locks the transaction pool + */ void lock() const; + + /** + * @brief unlocks the transaction pool + */ void unlock() const; // load/store operations + + /** + * @brief loads pool state (if any) from disk, and initializes pool + * + * @param config_folder folder name where pool state will be + * + * @return true + */ bool init(const std::string& config_folder); + + /** + * @brief attempts to save the transaction pool state to disk + * + * Currently fails (returns false) if the data directory from init() + * does not exist and cannot be created, but returns true even if + * saving to disk is unsuccessful. + * + * @return true in most cases (see above) + */ bool deinit(); + + /** + * @brief Chooses transactions for a block to include + * + * @param bl return-by-reference the block to fill in with transactions + * @param median_size the current median block size + * @param already_generated_coins the current total number of coins "minted" + * @param total_size return-by-reference the total size of the new block + * @param fee return-by-reference the total of fees from the included transactions + * + * @return true + */ bool fill_block_template(block &bl, size_t median_size, uint64_t already_generated_coins, size_t &total_size, uint64_t &fee); + + /** + * @brief get a list of all transactions in the pool + * + * @param txs return-by-reference the list of transactions + */ void get_transactions(std::list& txs) const; + + /** + * @brief get information about all transactions and key images in the pool + * + * see documentation on tx_info and spent_key_image_info for more details + * + * @param tx_infos return-by-reference the transactions' information + * @param key_image_infos return-by-reference the spent key images' information + * + * @return true + */ bool get_transactions_and_spent_keys_info(std::vector& tx_infos, std::vector& key_image_infos) const; + + /** + * @brief get a specific transaction from the pool + * + * @param h the hash of the transaction to get + * @param tx return-by-reference the transaction requested + * + * @return true if the transaction is found, otherwise false + */ bool get_transaction(const crypto::hash& h, transaction& tx) const; + + /** + * @brief get a list of all relayable transactions and their hashes + * + * "relayable" in this case means: + * nonzero fee + * hasn't been relayed too recently + * isn't old enough that relaying it is considered harmful + * + * @param txs return-by-reference the transactions and their hashes + * + * @return true + */ bool get_relayable_transactions(std::list>& txs) const; + + /** + * @brief tell the pool that certain transactions were just relayed + * + * @param txs the list of transactions (and their hashes) + */ void set_relayed(const std::list>& txs); + + /** + * @brief get the total number of transactions in the pool + * + * @return the number of transactions in the pool + */ size_t get_transactions_count() const; + + /** + * @brief get a string containing human-readable pool information + * + * @param short_format whether to use a shortened format for the info + * + * @return the string + */ std::string print_pool(bool short_format) const; + + /** + * @brief remove transactions from the pool which are no longer valid + * + * With new versions of the currency, what conditions render a transaction + * invalid may change. This function clears those which were received + * before a version change and no longer conform to requirements. + * + * @param version the version the transactions must conform to + * + * @return the number of transactions removed + */ size_t validate(uint8_t version); - /*bool flush_pool(const std::strig& folder); - bool inflate_pool(const std::strig& folder);*/ #define CURRENT_MEMPOOL_ARCHIVE_VER 11 + /** + * @brief serialize the transaction pool to/from disk + * + * If the archive version passed is older than the version compiled + * in, this function does nothing, as it cannot deserialize after a + * format change. + * + * @tparam archive_t the archive class + * @param a the archive to serialize to/from + * @param version the archive version + */ template void serialize(archive_t & a, const unsigned int version) { @@ -123,97 +333,169 @@ namespace cryptonote a & m_timed_out_transactions; } + /** + * @brief information about a single transaction + */ struct tx_details { - transaction tx; - size_t blob_size; - uint64_t fee; - crypto::hash max_used_block_id; - uint64_t max_used_block_height; - bool kept_by_block; - // - uint64_t last_failed_height; - crypto::hash last_failed_id; - time_t receive_time; + transaction tx; //!< the transaction + size_t blob_size; //!< the transaction's size + uint64_t fee; //!< the transaction's fee amount + crypto::hash max_used_block_id; //!< the hash of the highest block referenced by an input + uint64_t max_used_block_height; //!< the height of the highest block referenced by an input - time_t last_relayed_time; - bool relayed; + //! whether or not the transaction has been in a block before + /*! if the transaction was returned to the pool from the blockchain + * due to a reorg, then this will be true + */ + bool kept_by_block; + + //! the highest block the transaction referenced when last checking it failed + /*! if verifying a transaction's inputs fails, it's possible this is due + * to a reorg since it was created (if it used recently created outputs + * as inputs). + */ + uint64_t last_failed_height; + + //! the hash of the highest block the transaction referenced when last checking it failed + /*! if verifying a transaction's inputs fails, it's possible this is due + * to a reorg since it was created (if it used recently created outputs + * as inputs). + */ + crypto::hash last_failed_id; + + time_t receive_time; //!< the time when the transaction entered the pool + + time_t last_relayed_time; //!< the last time the transaction was relayed to the network + bool relayed; //!< whether or not the transaction has been relayed to the network }; private: + + /** + * @brief remove old transactions from the pool + * + * After a certain time, it is assumed that a transaction which has not + * yet been mined will likely not be mined. These transactions are removed + * from the pool to avoid buildup. + * + * @return true + */ bool remove_stuck_transactions(); + + /** + * @brief check if a transaction in the pool has a given spent key image + * + * @param key_im the spent key image to look for + * + * @return true if the spent key image is present, otherwise false + */ bool have_tx_keyimg_as_spent(const crypto::key_image& key_im) const; + + /** + * @brief check if any spent key image in a transaction is in the pool + * + * Checks if any of the spent key images in a given transaction are present + * in any of the transactions in the transaction pool. + * + * @note see tx_pool::have_tx_keyimg_as_spent + * + * @param tx the transaction to check spent key images of + * + * @return true if any spent key images are present in the pool, otherwise false + */ bool have_tx_keyimges_as_spent(const transaction& tx) const; + + /** + * @brief forget a transaction's spent key images + * + * Spent key images are stored separately from transactions for + * convenience/speed, so this is part of the process of removing + * a transaction from the pool. + * + * @param tx the transaction + * + * @return false if any key images to be removed cannot be found, otherwise true + */ bool remove_transaction_keyimages(const transaction& tx); + + /** + * @brief check if any of a transaction's spent key images are present in a given set + * + * @param kic the set of key images to check against + * @param tx the transaction to check + * + * @return true if any key images present in the set, otherwise false + */ static bool have_key_images(const std::unordered_set& kic, const transaction& tx); + + /** + * @brief append the key images from a transaction to the given set + * + * @param kic the set of key images to append to + * @param tx the transaction + * + * @return false if any append fails, otherwise true + */ static bool append_key_images(std::unordered_set& kic, const transaction& tx); + /** + * @brief check if a transaction is a valid candidate for inclusion in a block + * + * @param txd the transaction to check (and info about it) + * + * @return true if the transaction is good to go, otherwise false + */ bool is_transaction_ready_to_go(tx_details& txd) const; + + //! map a transactions (and related info) to their hashes typedef std::unordered_map transactions_container; + + //TODO: confirm the below comments and investigate whether or not this + // is the desired behavior + //! map key images to transactions which spent them + /*! this seems odd, but it seems that multiple transactions can exist + * in the pool which both have the same spent key. This would happen + * in the event of a reorg where someone creates a new/different + * transaction on the assumption that the original will not be in a + * block again. + */ typedef std::unordered_map > key_images_container; - mutable epee::critical_section m_transactions_lock; - transactions_container m_transactions; - key_images_container m_spent_key_images; + mutable epee::critical_section m_transactions_lock; //!< lock for the pool + transactions_container m_transactions; //!< container for transactions in the pool + + //! container for spent key images from the transactions in the pool + key_images_container m_spent_key_images; + + //TODO: this time should be a named constant somewhere, not hard-coded + //! interval on which to check for stale/"stuck" transactions epee::math_helper::once_a_time_seconds<30> m_remove_stuck_tx_interval; - //TODO: add fee_per_kb element to type tx_details and replace this - //functionality by just making m_transactions a std::set - sorted_tx_container m_txs_by_fee; + //TODO: look into doing this better + sorted_tx_container m_txs_by_fee; //!< container for transactions organized by fee per size + /** + * @brief get an iterator to a transaction in the sorted container + * + * @param id the hash of the transaction to look for + * + * @return an iterator, possibly to the end of the container if not found + */ sorted_tx_container::iterator find_tx_in_sorted_container(const crypto::hash& id) const; + //! transactions which are unlikely to be included in blocks + /*! These transactions are kept in RAM in case they *are* included + * in a block eventually, but this container is not saved to disk. + */ std::unordered_set m_timed_out_transactions; - //transactions_container m_alternative_transactions; - - std::string m_config_folder; + std::string m_config_folder; //!< the folder to save state to #if BLOCKCHAIN_DB == DB_LMDB - Blockchain& m_blockchain; + Blockchain& m_blockchain; //!< reference to the Blockchain object #else blockchain_storage& m_blockchain; #endif - /************************************************************************/ - /* */ - /************************************************************************/ - /*class inputs_visitor: public boost::static_visitor - { - key_images_container& m_spent_keys; - public: - inputs_visitor(key_images_container& spent_keys): m_spent_keys(spent_keys) - {} - bool operator()(const txin_to_key& tx) const - { - auto pr = m_spent_keys.insert(tx.k_image); - CHECK_AND_ASSERT_MES(pr.second, false, "Tried to insert transaction with input seems already spent, input: " << epee::string_tools::pod_to_hex(tx.k_image)); - return true; - } - bool operator()(const txin_gen& tx) const - { - CHECK_AND_ASSERT_MES(false, false, "coinbase transaction in memory pool"); - return false; - } - bool operator()(const txin_to_script& tx) const {return false;} - bool operator()(const txin_to_scripthash& tx) const {return false;} - }; */ - /************************************************************************/ - /* */ - /************************************************************************/ - class amount_visitor: public boost::static_visitor - { - public: - uint64_t operator()(const txin_to_key& tx) const - { - return tx.amount; - } - uint64_t operator()(const txin_gen& tx) const - { - CHECK_AND_ASSERT_MES(false, false, "coinbase transaction in memory pool"); - return 0; - } - uint64_t operator()(const txin_to_script& tx) const {return 0;} - uint64_t operator()(const txin_to_scripthash& tx) const {return 0;} - }; #if BLOCKCHAIN_DB == DB_LMDB #else