diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/blockchain_db/blockchain_db.h | 15 | ||||
| -rw-r--r-- | src/blockchain_db/lmdb/db_lmdb.cpp | 52 | ||||
| -rw-r--r-- | src/blockchain_db/lmdb/db_lmdb.h | 2 | ||||
| -rw-r--r-- | src/blockchain_db/testdb.h | 1 | ||||
| -rw-r--r-- | src/cryptonote_basic/cryptonote_basic_impl.cpp | 47 | ||||
| -rw-r--r-- | src/cryptonote_basic/cryptonote_basic_impl.h | 35 | ||||
| -rw-r--r-- | src/rpc/core_rpc_server.cpp | 76 | ||||
| -rw-r--r-- | src/rpc/core_rpc_server.h | 2 | ||||
| -rw-r--r-- | src/rpc/core_rpc_server_commands_defs.h | 27 |
9 files changed, 257 insertions, 0 deletions
diff --git a/src/blockchain_db/blockchain_db.h b/src/blockchain_db/blockchain_db.h index b38ec9e05..9628a5c4d 100644 --- a/src/blockchain_db/blockchain_db.h +++ b/src/blockchain_db/blockchain_db.h @@ -1306,6 +1306,21 @@ public: virtual bool get_pruned_tx_blobs_from(const crypto::hash& h, size_t count, std::vector<cryptonote::blobdata> &bd) const = 0; /** + * @brief Get all txids in the database (chain and pool) that match a certain nbits txid template + * + * To be more specific, for all `dbtxid` txids in the database, return `dbtxid` if + * `0 == cryptonote::compare_hash32_reversed_nbits(txid_template, dbtxid, nbits)`. + * + * @param txid_template the transaction id template + * @param nbits number of bits to compare against in the template + * @param max_num_txs The maximum number of txids to match, if we hit this limit, throw early + * @return std::vector<crypto::hash> the list of all matching txids + * + * @throw TX_EXISTS if the number of txids that match exceed `max_num_txs` + */ + virtual std::vector<crypto::hash> get_txids_loose(const crypto::hash& txid_template, std::uint32_t nbits, uint64_t max_num_txs = 0) = 0; + + /** * @brief fetches a variable number of blocks and transactions from the given height, in canonical blockchain order * * The subclass should return the blocks and transactions stored from the one with the given diff --git a/src/blockchain_db/lmdb/db_lmdb.cpp b/src/blockchain_db/lmdb/db_lmdb.cpp index 4178c862b..2c015faee 100644 --- a/src/blockchain_db/lmdb/db_lmdb.cpp +++ b/src/blockchain_db/lmdb/db_lmdb.cpp @@ -3144,6 +3144,58 @@ bool BlockchainLMDB::get_pruned_tx_blobs_from(const crypto::hash& h, size_t coun return true; } +std::vector<crypto::hash> BlockchainLMDB::get_txids_loose(const crypto::hash& txid_template, std::uint32_t bits, uint64_t max_num_txs) +{ + LOG_PRINT_L3("BlockchainLMDB::" << __func__); + check_open(); + + std::vector<crypto::hash> matching_hashes; + + TXN_PREFIX_RDONLY(); // Start a read-only transaction + RCURSOR(tx_indices); // Open cursors to the tx_indices and txpool_meta databases + RCURSOR(txpool_meta); + + // Search on-chain and pool transactions together, starting with on-chain txs + MDB_cursor* cursor = m_cur_tx_indices; + MDB_val k = zerokval; // tx_indicies DB uses a dummy key + MDB_val_set(v, txid_template); // tx_indicies DB indexes data values by crypto::hash value on front + MDB_cursor_op op = MDB_GET_BOTH_RANGE; // Set the cursor to the first key/value pair >= the given key + bool doing_chain = true; // this variable tells us whether we are processing chain or pool txs + while (1) + { + const int get_result = mdb_cursor_get(cursor, &k, &v, op); + op = doing_chain ? MDB_NEXT_DUP : MDB_NEXT; // Set the cursor to the next key/value pair + if (get_result && get_result != MDB_NOTFOUND) + throw0(DB_ERROR(lmdb_error("DB error attempting to fetch txid range", get_result).c_str())); + + // In tx_indicies, the hash is stored at the data, in txpool_meta at the key + const crypto::hash* const p_dbtxid = (const crypto::hash*)(doing_chain ? v.mv_data : k.mv_data); + + // Check if we reached the end of a DB or the hashes no longer match the template + if (get_result == MDB_NOTFOUND || compare_hash32_reversed_nbits(txid_template, *p_dbtxid, bits)) + { + if (doing_chain) // done with chain processing, switch to pool processing + { + k.mv_size = sizeof(crypto::hash); // txpool_meta DB is indexed using crypto::hash as keys + k.mv_data = (void*) txid_template.data; + cursor = m_cur_txpool_meta; // switch databases + op = MDB_SET_RANGE; // Set the cursor to the first key >= the given key + doing_chain = false; + continue; + } + break; // if we get to this point, then we finished pool processing and we are done + } + else if (matching_hashes.size() >= max_num_txs && max_num_txs != 0) + throw0(TX_EXISTS("number of tx hashes in template range exceeds maximum")); + + matching_hashes.push_back(*p_dbtxid); + } + + TXN_POSTFIX_RDONLY(); // End the read-only transaction + + return matching_hashes; +} + bool BlockchainLMDB::get_blocks_from(uint64_t start_height, size_t min_block_count, size_t max_block_count, size_t max_tx_count, size_t max_size, std::vector<std::pair<std::pair<cryptonote::blobdata, crypto::hash>, std::vector<std::pair<crypto::hash, cryptonote::blobdata>>>>& blocks, bool pruned, bool skip_coinbase, bool get_miner_tx_hash) 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 c352458b4..95e7b2aa4 100644 --- a/src/blockchain_db/lmdb/db_lmdb.h +++ b/src/blockchain_db/lmdb/db_lmdb.h @@ -262,6 +262,8 @@ public: virtual bool get_prunable_tx_blob(const crypto::hash& h, cryptonote::blobdata &tx) const; virtual bool get_prunable_tx_hash(const crypto::hash& tx_hash, crypto::hash &prunable_hash) const; + virtual std::vector<crypto::hash> get_txids_loose(const crypto::hash& h, std::uint32_t bits, uint64_t max_num_txs = 0); + virtual uint64_t get_tx_count() const; virtual std::vector<transaction> get_tx_list(const std::vector<crypto::hash>& hlist) const; diff --git a/src/blockchain_db/testdb.h b/src/blockchain_db/testdb.h index 946f26270..a27183b2c 100644 --- a/src/blockchain_db/testdb.h +++ b/src/blockchain_db/testdb.h @@ -71,6 +71,7 @@ public: virtual bool get_pruned_tx_blob(const crypto::hash& h, cryptonote::blobdata &tx) const override { return false; } virtual bool get_pruned_tx_blobs_from(const crypto::hash& h, size_t count, std::vector<cryptonote::blobdata> &bd) const override { return false; } virtual bool get_blocks_from(uint64_t start_height, size_t min_block_count, size_t max_block_count, size_t max_tx_count, size_t max_size, std::vector<std::pair<std::pair<cryptonote::blobdata, crypto::hash>, std::vector<std::pair<crypto::hash, cryptonote::blobdata>>>>& blocks, bool pruned, bool skip_coinbase, bool get_miner_tx_hash) const override { return false; } + virtual std::vector<crypto::hash> get_txids_loose(const crypto::hash& h, std::uint32_t bits, uint64_t max_num_txs = 0) override { return {}; } virtual bool get_prunable_tx_blob(const crypto::hash& h, cryptonote::blobdata &tx) const override { return false; } virtual bool get_prunable_tx_hash(const crypto::hash& tx_hash, crypto::hash &prunable_hash) const override { return false; } virtual uint64_t get_block_height(const crypto::hash& h) const override { return 0; } diff --git a/src/cryptonote_basic/cryptonote_basic_impl.cpp b/src/cryptonote_basic/cryptonote_basic_impl.cpp index 9bde20609..7fe398283 100644 --- a/src/cryptonote_basic/cryptonote_basic_impl.cpp +++ b/src/cryptonote_basic/cryptonote_basic_impl.cpp @@ -310,6 +310,53 @@ namespace cryptonote { bool operator ==(const cryptonote::block& a, const cryptonote::block& b) { return cryptonote::get_block_hash(a) == cryptonote::get_block_hash(b); } + //-------------------------------------------------------------------------------- + int compare_hash32_reversed_nbits(const crypto::hash& ha, const crypto::hash& hb, unsigned int nbits) + { + static_assert(sizeof(uint64_t) * 4 == sizeof(crypto::hash), "hash is wrong size"); + + // We have to copy these buffers b/c of the strict aliasing rule + uint64_t va[4]; + memcpy(va, &ha, sizeof(crypto::hash)); + uint64_t vb[4]; + memcpy(vb, &hb, sizeof(crypto::hash)); + + for (int n = 3; n >= 0 && nbits; --n) + { + const unsigned int msb_nbits = std::min<unsigned int>(64, nbits); + const uint64_t lsb_nbits_dropped = static_cast<uint64_t>(64 - msb_nbits); + const uint64_t van = SWAP64LE(va[n]) >> lsb_nbits_dropped; + const uint64_t vbn = SWAP64LE(vb[n]) >> lsb_nbits_dropped; + nbits -= msb_nbits; + + if (van < vbn) return -1; else if (van > vbn) return 1; + } + + return 0; + } + + crypto::hash make_hash32_loose_template(unsigned int nbits, const crypto::hash& h) + { + static_assert(sizeof(uint64_t) * 4 == sizeof(crypto::hash), "hash is wrong size"); + + // We have to copy this buffer b/c of the strict aliasing rule + uint64_t vh[4]; + memcpy(vh, &h, sizeof(crypto::hash)); + + for (int n = 3; n >= 0; --n) + { + const unsigned int msb_nbits = std::min<unsigned int>(64, nbits); + const uint64_t mask = msb_nbits ? (~((std::uint64_t(1) << (64 - msb_nbits)) - 1)) : 0; + nbits -= msb_nbits; + + vh[n] &= SWAP64LE(mask); + } + + crypto::hash res; + memcpy(&res, vh, sizeof(crypto::hash)); + return res; + } + //-------------------------------------------------------------------------------- } //-------------------------------------------------------------------------------- diff --git a/src/cryptonote_basic/cryptonote_basic_impl.h b/src/cryptonote_basic/cryptonote_basic_impl.h index 984bee19f..53dbc47d7 100644 --- a/src/cryptonote_basic/cryptonote_basic_impl.h +++ b/src/cryptonote_basic/cryptonote_basic_impl.h @@ -112,6 +112,41 @@ namespace cryptonote { bool operator ==(const cryptonote::transaction& a, const cryptonote::transaction& b); bool operator ==(const cryptonote::block& a, const cryptonote::block& b); + + /************************************************************************/ + /* K-anonymity helper functions */ + /************************************************************************/ + + /** + * @brief Compares two hashes up to `nbits` bits in reverse byte order ("LMDB key order") + * + * The comparison essentially goes from the 31th, 30th, 29th, ..., 0th byte and compares the MSBs + * to the LSBs in each byte, up to `nbits` bits. If we use up `nbits` bits before finding a + * difference in the bits between the two hashes, we return 0. If we encounter a zero bit in `ha` + * where `hb` has a one in that bit place, then we reutrn -1. If the converse scenario happens, + * we return a 1. When `nbits` == 256 (there are 256 bits in `crypto::hash`), calling this is + * functionally identical to `BlockchainLMDB::compare_hash32`. + * + * @param ha left hash + * @param hb right hash + * @param nbits the number of bits to consider, a higher value means a finer comparison + * @return int 0 if ha == hb, -1 if ha < hb, 1 if ha > hb + */ + int compare_hash32_reversed_nbits(const crypto::hash& ha, const crypto::hash& hb, unsigned int nbits); + + /** + * @brief Make a template which matches `h` in LMDB order up to `nbits` bits, safe for k-anonymous fetching + * + * To be more technical, this function creates a hash which satifies the following property: + * For all `H_prime` s.t. `0 == compare_hash32_reversed_nbits(real_hash, H_prime, nbits)`, + * `1 > compare_hash32_reversed_nbits(real_hash, H_prime, 256)`. + * In other words, we return the "least" hash nbit-equal to `real_hash`. + * + * @param nbits The number of "MSB" bits to include in the template + * @param real_hash The original hash which contains more information than we want to disclose + * @return crypto::hash hash template that contains `nbits` bits matching real_hash and no more + */ + crypto::hash make_hash32_loose_template(unsigned int nbits, const crypto::hash& real_hash); } bool parse_hash256(const std::string &str_hash, crypto::hash& hash); diff --git a/src/rpc/core_rpc_server.cpp b/src/rpc/core_rpc_server.cpp index 03e9ec494..a6162c3f9 100644 --- a/src/rpc/core_rpc_server.cpp +++ b/src/rpc/core_rpc_server.cpp @@ -3535,6 +3535,82 @@ namespace cryptonote return true; } //------------------------------------------------------------------------------------------------------------------------------ + bool core_rpc_server::on_get_txids_loose(const COMMAND_RPC_GET_TXIDS_LOOSE::request& req, COMMAND_RPC_GET_TXIDS_LOOSE::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx) + { + RPC_TRACKER(get_txids_loose); + + // Maybe don't use bootstrap since this endpoint is meant to retreive TXIDs w/ k-anonymity, + // so shunting this request to a random node seems counterproductive. + +#if BYTE_ORDER == LITTLE_ENDIAN + const uint64_t max_num_txids = RESTRICTED_SPENT_KEY_IMAGES_COUNT * (m_restricted ? 1 : 10); + + // Sanity check parameters + if (req.num_matching_bits > 256) + { + error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM; + error_resp.message = "There are only 256 bits in a hash, you gave too many"; + return false; + } + + // Attempt to guess when bit count is too low before fetching, within a certain margin of error + const uint64_t num_txs_ever = m_core.get_blockchain_storage().get_db().get_tx_count(); + const uint64_t num_expected_fetch = (num_txs_ever >> std::min((int) req.num_matching_bits, 63)); + const uint64_t max_num_txids_with_margin = 2 * max_num_txids; + if (num_expected_fetch > max_num_txids_with_margin) + { + error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM; + error_resp.message = "Trying to search with too few matching bits, detected before fetching"; + return false; + } + + // Convert txid template to a crypto::hash + crypto::hash search_hash; + if (!epee::string_tools::hex_to_pod(req.txid_template, search_hash)) + { + error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM; + error_resp.message = "Could not decode hex txid"; + return false; + } + // Check that txid template is zeroed correctly for number of given matchign bits + else if (search_hash != make_hash32_loose_template(req.num_matching_bits, search_hash)) + { + error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM; + error_resp.message = "Txid template is not zeroed correctly for number of bits. You could be leaking true txid!"; + return false; + } + + try + { + // Do the DB fetch + const auto txids = m_core.get_blockchain_storage().get_db().get_txids_loose(search_hash, req.num_matching_bits, max_num_txids); + // Fill out response form + for (const auto& txid : txids) + res.txids.emplace_back(epee::string_tools::pod_to_hex(txid)); + } + catch (const TX_EXISTS&) + { + error_resp.code = CORE_RPC_ERROR_CODE_WRONG_PARAM; + error_resp.message = "Trying to search with too few matching bits"; + return false; + } + catch (const std::exception& e) + { + error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR; + error_resp.message = std::string("Error during get_txids_loose: ") + e.what(); + return false; + } + + res.status = CORE_RPC_STATUS_OK; + return true; +#else // BYTE_ORDER == BIG_ENDIAN + // BlockchainLMDB::compare_hash32 has different key ordering (thus different txid templates) on BE systems + error_resp.code = CORE_RPC_ERROR_CODE_INTERNAL_ERROR; + error_resp.message = "Due to implementation details, this feature is not available on big-endian daemons"; + return false; +#endif + } + //------------------------------------------------------------------------------------------------------------------------------ bool core_rpc_server::on_rpc_access_submit_nonce(const COMMAND_RPC_ACCESS_SUBMIT_NONCE::request& req, COMMAND_RPC_ACCESS_SUBMIT_NONCE::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx) { RPC_TRACKER(rpc_access_submit_nonce); diff --git a/src/rpc/core_rpc_server.h b/src/rpc/core_rpc_server.h index 790d5eb23..7c31d2539 100644 --- a/src/rpc/core_rpc_server.h +++ b/src/rpc/core_rpc_server.h @@ -178,6 +178,7 @@ namespace cryptonote MAP_JON_RPC_WE("get_output_distribution", on_get_output_distribution, COMMAND_RPC_GET_OUTPUT_DISTRIBUTION) MAP_JON_RPC_WE_IF("prune_blockchain", on_prune_blockchain, COMMAND_RPC_PRUNE_BLOCKCHAIN, !m_restricted) MAP_JON_RPC_WE_IF("flush_cache", on_flush_cache, COMMAND_RPC_FLUSH_CACHE, !m_restricted) + MAP_JON_RPC_WE("get_txids_loose", on_get_txids_loose, COMMAND_RPC_GET_TXIDS_LOOSE) MAP_JON_RPC_WE("rpc_access_info", on_rpc_access_info, COMMAND_RPC_ACCESS_INFO) MAP_JON_RPC_WE("rpc_access_submit_nonce",on_rpc_access_submit_nonce, COMMAND_RPC_ACCESS_SUBMIT_NONCE) MAP_JON_RPC_WE("rpc_access_pay", on_rpc_access_pay, COMMAND_RPC_ACCESS_PAY) @@ -255,6 +256,7 @@ namespace cryptonote bool on_get_output_distribution(const COMMAND_RPC_GET_OUTPUT_DISTRIBUTION::request& req, COMMAND_RPC_GET_OUTPUT_DISTRIBUTION::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); bool on_prune_blockchain(const COMMAND_RPC_PRUNE_BLOCKCHAIN::request& req, COMMAND_RPC_PRUNE_BLOCKCHAIN::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); bool on_flush_cache(const COMMAND_RPC_FLUSH_CACHE::request& req, COMMAND_RPC_FLUSH_CACHE::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); + bool on_get_txids_loose(const COMMAND_RPC_GET_TXIDS_LOOSE::request& req, COMMAND_RPC_GET_TXIDS_LOOSE::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); bool on_rpc_access_info(const COMMAND_RPC_ACCESS_INFO::request& req, COMMAND_RPC_ACCESS_INFO::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); bool on_rpc_access_submit_nonce(const COMMAND_RPC_ACCESS_SUBMIT_NONCE::request& req, COMMAND_RPC_ACCESS_SUBMIT_NONCE::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); bool on_rpc_access_pay(const COMMAND_RPC_ACCESS_PAY::request& req, COMMAND_RPC_ACCESS_PAY::response& res, epee::json_rpc::error& error_resp, const connection_context *ctx = NULL); diff --git a/src/rpc/core_rpc_server_commands_defs.h b/src/rpc/core_rpc_server_commands_defs.h index 819d77c1f..37f9b8f2f 100644 --- a/src/rpc/core_rpc_server_commands_defs.h +++ b/src/rpc/core_rpc_server_commands_defs.h @@ -2793,4 +2793,31 @@ namespace cryptonote typedef epee::misc_utils::struct_init<response_t> response; }; + struct COMMAND_RPC_GET_TXIDS_LOOSE + { + struct request_t: public rpc_request_base + { + std::string txid_template; + std::uint32_t num_matching_bits; + + BEGIN_KV_SERIALIZE_MAP() + KV_SERIALIZE_PARENT(rpc_request_base) + KV_SERIALIZE(txid_template) + KV_SERIALIZE(num_matching_bits) + END_KV_SERIALIZE_MAP() + }; + typedef epee::misc_utils::struct_init<request_t> request; + + struct response_t: public rpc_response_base + { + std::vector<std::string> txids; + + BEGIN_KV_SERIALIZE_MAP() + KV_SERIALIZE_PARENT(rpc_response_base) + KV_SERIALIZE(txids) + END_KV_SERIALIZE_MAP() + }; + typedef epee::misc_utils::struct_init<response_t> response; + }; + } |