Git-Mirrors/monero
1
0
Fork 0
mirror of https://github.com/monero-project/monero.git synced 2024-10-01 11:49:47 -04:00
Code Issues Packages Projects Releases Wiki Activity
f794d3b3df
monero/src/cryptonote_core/tx_pool.cpp
moneromooo-monero 08343abaf4
tx_pool: fix loading with colliding key images 
A key image may be present more than once if all but one of the
txes spending that key image are coming from blocks. When loading
a txpool from storage, we must load the one that's not from a
block first to avoid rejection
2018-04-11 15:27:56 +01:00

1323 lines
50 KiB
C++
Raw Blame History

// Copyright (c) 2014-2018, The Monero Project
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are
// permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice, this list
// of conditions and the following disclaimer in the documentation and/or other
// materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its contributors may be
// used to endorse or promote products derived from this software without specific
// prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
#include <algorithm>
#include <boost/filesystem.hpp>
#include <unordered_set>
#include <vector>
#include "tx_pool.h"
#include "cryptonote_tx_utils.h"
#include "cryptonote_basic/cryptonote_boost_serialization.h"
#include "cryptonote_config.h"
#include "blockchain.h"
#include "blockchain_db/blockchain_db.h"
#include "common/boost_serialization_helper.h"
#include "common/int-util.h"
#include "misc_language.h"
#include "warnings.h"
#include "common/perf_timer.h"
#include "crypto/hash.h"
#undef MONERO_DEFAULT_LOG_CATEGORY
#define MONERO_DEFAULT_LOG_CATEGORY "txpool"
DISABLE_VS_WARNINGS(4244 4345 4503) //'boost::foreach_detail_::or_' : decorated name length exceeded, name was truncated
using namespace crypto;
namespace cryptonote
{
namespace
{
//TODO: constants such as these should at least be in the header,
// but probably somewhere more accessible to the rest of the
// codebase. As it stands, it is at best nontrivial to test
// whether or not changing these parameters (or adding new)
// will work correctly.
time_t const MIN_RELAY_TIME = (60 * 5); // only start re-relaying transactions after that many seconds
time_t const MAX_RELAY_TIME = (60 * 60 * 4); // at most that many seconds between resends
float const ACCEPT_THRESHOLD = 1.0f;
// a kind of increasing backoff within min/max bounds
uint64_t get_relay_delay(time_t now, time_t received)
{
time_t d = (now - received + MIN_RELAY_TIME) / MIN_RELAY_TIME * MIN_RELAY_TIME;
if (d > MAX_RELAY_TIME)
d = MAX_RELAY_TIME;
return d;
}
uint64_t template_accept_threshold(uint64_t amount)
{
return amount * ACCEPT_THRESHOLD;
}
uint64_t get_transaction_size_limit(uint8_t version)
{
return get_min_block_size(version) - CRYPTONOTE_COINBASE_BLOB_RESERVED_SIZE;
}
// This class is meant to create a batch when none currently exists.
// If a batch exists, it can't be from another thread, since we can
// only be called with the txpool lock taken, and it is held during
// the whole prepare/handle/cleanup incoming block sequence.
class LockedTXN {
public:
LockedTXN(Blockchain &b): m_blockchain(b), m_batch(false) {
m_batch = m_blockchain.get_db().batch_start();
}
~LockedTXN() { try { if (m_batch) { m_blockchain.get_db().batch_stop(); } } catch (const std::exception &e) { MWARNING("LockedTXN dtor filtering exception: " << e.what()); } }
private:
Blockchain &m_blockchain;
bool m_batch;
};
}
//---------------------------------------------------------------------------------
//---------------------------------------------------------------------------------
tx_memory_pool::tx_memory_pool(Blockchain& bchs): m_blockchain(bchs), m_txpool_max_size(DEFAULT_TXPOOL_MAX_SIZE), m_txpool_size(0)
{
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::add_tx(transaction &tx, /*const crypto::hash& tx_prefix_hash,*/ const crypto::hash &id, size_t blob_size, tx_verification_context& tvc, bool kept_by_block, bool relayed, bool do_not_relay, uint8_t version)
{
// this should already be called with that lock, but let's make it explicit for clarity
CRITICAL_REGION_LOCAL(m_transactions_lock);
PERF_TIMER(add_tx);
if (tx.version == 0)
{
// v0 never accepted
LOG_PRINT_L1("transaction version 0 is invalid");
tvc.m_verifivation_failed = true;
return false;
}
// we do not accept transactions that timed out before, unless they're
// kept_by_block
if (!kept_by_block && m_timed_out_transactions.find(id) != m_timed_out_transactions.end())
{
// not clear if we should set that, since verifivation (sic) did not fail before, since
// the tx was accepted before timing out.
tvc.m_verifivation_failed = true;
return false;
}
if(!check_inputs_types_supported(tx))
{
tvc.m_verifivation_failed = true;
tvc.m_invalid_input = true;
return false;
}
// fee per kilobyte, size rounded up.
uint64_t fee;
if (tx.version == 1)
{
uint64_t inputs_amount = 0;
if(!get_inputs_money_amount(tx, inputs_amount))
{
tvc.m_verifivation_failed = true;
return false;
}
uint64_t outputs_amount = get_outs_money_amount(tx);
if(outputs_amount > inputs_amount)
{
LOG_PRINT_L1("transaction use more money than it has: use " << print_money(outputs_amount) << ", have " << print_money(inputs_amount));
tvc.m_verifivation_failed = true;
tvc.m_overspend = true;
return false;
}
else if(outputs_amount == inputs_amount)
{
LOG_PRINT_L1("transaction fee is zero: outputs_amount == inputs_amount, rejecting.");
tvc.m_verifivation_failed = true;
tvc.m_fee_too_low = true;
return false;
}
fee = inputs_amount - outputs_amount;
}
else
{
fee = tx.rct_signatures.txnFee;
}
if (!kept_by_block && !m_blockchain.check_fee(blob_size, fee))
{
tvc.m_verifivation_failed = true;
tvc.m_fee_too_low = true;
return false;
}
size_t tx_size_limit = get_transaction_size_limit(version);
if (!kept_by_block && blob_size > tx_size_limit)
{
LOG_PRINT_L1("transaction is too big: " << blob_size << " bytes, maximum size: " << tx_size_limit);
tvc.m_verifivation_failed = true;
tvc.m_too_big = true;
return false;
}
// 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))
{
mark_double_spend(tx);
LOG_PRINT_L1("Transaction with id= "<< id << " used already spent key images");
tvc.m_verifivation_failed = true;
tvc.m_double_spend = true;
return false;
}
}
if (!m_blockchain.check_tx_outputs(tx, tvc))
{
LOG_PRINT_L1("Transaction with id= "<< id << " has at least one invalid output");
tvc.m_verifivation_failed = true;
tvc.m_invalid_output = true;
return false;
}
// assume failure during verification steps until success is certain
tvc.m_verifivation_failed = true;
time_t receive_time = time(nullptr);
crypto::hash max_used_block_id = null_hash;
uint64_t max_used_block_height = 0;
cryptonote::txpool_tx_meta_t meta;
bool ch_inp_res = m_blockchain.check_tx_inputs(tx, max_used_block_height, max_used_block_id, tvc, kept_by_block);
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)
{
meta.blob_size = blob_size;
meta.fee = fee;
meta.max_used_block_id = null_hash;
meta.max_used_block_height = 0;
meta.last_failed_height = 0;
meta.last_failed_id = null_hash;
meta.kept_by_block = kept_by_block;
meta.receive_time = receive_time;
meta.last_relayed_time = time(NULL);
meta.relayed = relayed;
meta.do_not_relay = do_not_relay;
meta.double_spend_seen = have_tx_keyimges_as_spent(tx);
memset(meta.padding, 0, sizeof(meta.padding));
try
{
CRITICAL_REGION_LOCAL1(m_blockchain);
LockedTXN lock(m_blockchain);
m_blockchain.add_txpool_tx(tx, meta);
if (!insert_key_images(tx, kept_by_block))
return false;
m_txs_by_fee_and_receive_time.emplace(std::pair<double, std::time_t>(fee / (double)blob_size, receive_time), id);
}
catch (const std::exception &e)
{
MERROR("transaction already exists at inserting in memory pool: " << e.what());
return false;
}
tvc.m_verifivation_impossible = true;
tvc.m_added_to_pool = true;
}else
{
LOG_PRINT_L1("tx used wrong inputs, rejected");
tvc.m_verifivation_failed = true;
tvc.m_invalid_input = true;
return false;
}
}else
{
//update transactions container
meta.blob_size = blob_size;
meta.kept_by_block = kept_by_block;
meta.fee = fee;
meta.max_used_block_id = max_used_block_id;
meta.max_used_block_height = max_used_block_height;
meta.last_failed_height = 0;
meta.last_failed_id = null_hash;
meta.receive_time = receive_time;
meta.last_relayed_time = time(NULL);
meta.relayed = relayed;
meta.do_not_relay = do_not_relay;
meta.double_spend_seen = false;
memset(meta.padding, 0, sizeof(meta.padding));
try
{
CRITICAL_REGION_LOCAL1(m_blockchain);
LockedTXN lock(m_blockchain);
m_blockchain.remove_txpool_tx(get_transaction_hash(tx));
m_blockchain.add_txpool_tx(tx, meta);
if (!insert_key_images(tx, kept_by_block))
return false;
m_txs_by_fee_and_receive_time.emplace(std::pair<double, std::time_t>(fee / (double)blob_size, receive_time), id);
}
catch (const std::exception &e)
{
MERROR("internal error: transaction already exists at inserting in memory pool: " << e.what());
return false;
}
tvc.m_added_to_pool = true;
if(meta.fee > 0 && !do_not_relay)
tvc.m_should_be_relayed = true;
}
tvc.m_verifivation_failed = false;
m_txpool_size += blob_size;
MINFO("Transaction added to pool: txid " << id << " bytes: " << blob_size << " fee/byte: " << (fee / (double)blob_size));
prune(m_txpool_max_size);
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::add_tx(transaction &tx, tx_verification_context& tvc, bool keeped_by_block, bool relayed, bool do_not_relay, uint8_t version)
{
crypto::hash h = null_hash;
size_t blob_size = 0;
if (!get_transaction_hash(tx, h, blob_size) || blob_size == 0)
return false;
return add_tx(tx, h, blob_size, tvc, keeped_by_block, relayed, do_not_relay, version);
}
//---------------------------------------------------------------------------------
size_t tx_memory_pool::get_txpool_size() const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
return m_txpool_size;
}
//---------------------------------------------------------------------------------
void tx_memory_pool::set_txpool_max_size(size_t bytes)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
m_txpool_max_size = bytes;
}
//---------------------------------------------------------------------------------
void tx_memory_pool::prune(size_t bytes)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
if (bytes == 0)
bytes = m_txpool_max_size;
CRITICAL_REGION_LOCAL1(m_blockchain);
LockedTXN lock(m_blockchain);
// this will never remove the first one, but we don't care
auto it = --m_txs_by_fee_and_receive_time.end();
while (it != m_txs_by_fee_and_receive_time.begin())
{
if (m_txpool_size <= bytes)
break;
try
{
const crypto::hash &txid = it->second;
txpool_tx_meta_t meta;
if (!m_blockchain.get_txpool_tx_meta(txid, meta))
{
MERROR("Failed to find tx in txpool");
return;
}
// don't prune the kept_by_block ones, they're likely added because we're adding a block with those
if (meta.kept_by_block)
{
--it;
continue;
}
cryptonote::blobdata txblob = m_blockchain.get_txpool_tx_blob(txid);
cryptonote::transaction tx;
if (!parse_and_validate_tx_from_blob(txblob, tx))
{
MERROR("Failed to parse tx from txpool");
return;
}
// remove first, in case this throws, so key images aren't removed
MINFO("Pruning tx " << txid << " from txpool: size: " << it->first.second << ", fee/byte: " << it->first.first);
m_blockchain.remove_txpool_tx(txid);
m_txpool_size -= txblob.size();
remove_transaction_keyimages(tx);
MINFO("Pruned tx " << txid << " from txpool: size: " << it->first.second << ", fee/byte: " << it->first.first);
m_txs_by_fee_and_receive_time.erase(it--);
}
catch (const std::exception &e)
{
MERROR("Error while pruning txpool: " << e.what());
return;
}
}
if (m_txpool_size > bytes)
MINFO("Pool size after pruning is larger than limit: " << m_txpool_size << "/" << bytes);
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::insert_key_images(const transaction &tx, bool kept_by_block)
{
for(const auto& in: tx.vin)
{
const crypto::hash id = get_transaction_hash(tx);
CHECKED_GET_SPECIFIC_VARIANT(in, const txin_to_key, txin, false);
std::unordered_set<crypto::hash>& 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: 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);
CHECK_AND_ASSERT_MES(ins_res.second, false, "internal error: try to insert duplicate iterator in key_image set");
}
return true;
}
//---------------------------------------------------------------------------------
//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);
CRITICAL_REGION_LOCAL1(m_blockchain);
// ND: Speedup
// 1. Move transaction hash calcuation outside of loop. ._.
crypto::hash actual_hash = get_transaction_hash(tx);
for(const txin_v& vi: tx.vin)
{
CHECKED_GET_SPECIFIC_VARIANT(vi, const txin_to_key, txin, false);
auto it = m_spent_key_images.find(txin.k_image);
CHECK_AND_ASSERT_MES(it != m_spent_key_images.end(), false, "failed to find transaction input in key images. img=" << txin.k_image << ENDL
<< "transaction id = " << get_transaction_hash(tx));
std::unordered_set<crypto::hash>& key_image_set = it->second;
CHECK_AND_ASSERT_MES(key_image_set.size(), false, "empty key_image set, img=" << txin.k_image << ENDL
<< "transaction id = " << actual_hash);
auto it_in_set = key_image_set.find(actual_hash);
CHECK_AND_ASSERT_MES(it_in_set != key_image_set.end(), false, "transaction id not found in key_image set, img=" << txin.k_image << ENDL
<< "transaction id = " << actual_hash);
key_image_set.erase(it_in_set);
if(!key_image_set.size())
{
//it is now empty hash container for this key_image
m_spent_key_images.erase(it);
}
}
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::take_tx(const crypto::hash &id, transaction &tx, size_t& blob_size, uint64_t& fee, bool &relayed, bool &do_not_relay, bool &double_spend_seen)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
auto sorted_it = find_tx_in_sorted_container(id);
if (sorted_it == m_txs_by_fee_and_receive_time.end())
return false;
try
{
LockedTXN lock(m_blockchain);
txpool_tx_meta_t meta;
if (!m_blockchain.get_txpool_tx_meta(id, meta))
{
MERROR("Failed to find tx in txpool");
return false;
}
cryptonote::blobdata txblob = m_blockchain.get_txpool_tx_blob(id);
if (!parse_and_validate_tx_from_blob(txblob, tx))
{
MERROR("Failed to parse tx from txpool");
return false;
}
blob_size = meta.blob_size;
fee = meta.fee;
relayed = meta.relayed;
do_not_relay = meta.do_not_relay;
double_spend_seen = meta.double_spend_seen;
// remove first, in case this throws, so key images aren't removed
m_blockchain.remove_txpool_tx(id);
m_txpool_size -= blob_size;
remove_transaction_keyimages(tx);
}
catch (const std::exception &e)
{
MERROR("Failed to remove tx from txpool: " << e.what());
return false;
}
m_txs_by_fee_and_receive_time.erase(sorted_it);
return true;
}
//---------------------------------------------------------------------------------
void tx_memory_pool::on_idle()
{
m_remove_stuck_tx_interval.do_call([this](){return remove_stuck_transactions();});
}
//---------------------------------------------------------------------------------
sorted_tx_container::iterator tx_memory_pool::find_tx_in_sorted_container(const crypto::hash& id) const
{
return std::find_if( m_txs_by_fee_and_receive_time.begin(), m_txs_by_fee_and_receive_time.end()
, [&](const sorted_tx_container::value_type& a){
return a.second == id;
}
);
}
//---------------------------------------------------------------------------------
//TODO: investigate whether boolean return is appropriate
bool tx_memory_pool::remove_stuck_transactions()
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
std::unordered_set<crypto::hash> remove;
m_blockchain.for_all_txpool_txes([this, &remove](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata*) {
uint64_t tx_age = time(nullptr) - meta.receive_time;
if((tx_age > CRYPTONOTE_MEMPOOL_TX_LIVETIME && !meta.kept_by_block) ||
(tx_age > CRYPTONOTE_MEMPOOL_TX_FROM_ALT_BLOCK_LIVETIME && meta.kept_by_block) )
{
LOG_PRINT_L1("Tx " << txid << " removed from tx pool due to outdated, age: " << tx_age );
auto sorted_it = find_tx_in_sorted_container(txid);
if (sorted_it == m_txs_by_fee_and_receive_time.end())
{
LOG_PRINT_L1("Removing tx " << txid << " from tx pool, but it was not found in the sorted txs container!");
}
else
{
m_txs_by_fee_and_receive_time.erase(sorted_it);
}
m_timed_out_transactions.insert(txid);
remove.insert(txid);
}
return true;
}, false);
if (!remove.empty())
{
LockedTXN lock(m_blockchain);
for (const crypto::hash &txid: remove)
{
try
{
cryptonote::blobdata bd = m_blockchain.get_txpool_tx_blob(txid);
cryptonote::transaction tx;
if (!parse_and_validate_tx_from_blob(bd, tx))
{
MERROR("Failed to parse tx from txpool");
// continue
}
else
{
// remove first, so we only remove key images if the tx removal succeeds
m_blockchain.remove_txpool_tx(txid);
m_txpool_size -= bd.size();
remove_transaction_keyimages(tx);
}
}
catch (const std::exception &e)
{
MWARNING("Failed to remove stuck transaction: " << txid);
// ignore error
}
}
}
return true;
}
//---------------------------------------------------------------------------------
//TODO: investigate whether boolean return is appropriate
bool tx_memory_pool::get_relayable_transactions(std::list<std::pair<crypto::hash, cryptonote::blobdata>> &txs) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
const uint64_t now = time(NULL);
m_blockchain.for_all_txpool_txes([this, now, &txs](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *){
// 0 fee transactions are never relayed
if(meta.fee > 0 && !meta.do_not_relay && now - meta.last_relayed_time > get_relay_delay(now, meta.receive_time))
{
// if the tx is older than half the max lifetime, we don't re-relay it, to avoid a problem
// mentioned by smooth where nodes would flush txes at slightly different times, causing
// flushed txes to be re-added when received from a node which was just about to flush it
uint64_t max_age = meta.kept_by_block ? CRYPTONOTE_MEMPOOL_TX_FROM_ALT_BLOCK_LIVETIME : CRYPTONOTE_MEMPOOL_TX_LIVETIME;
if (now - meta.receive_time <= max_age / 2)
{
try
{
cryptonote::blobdata bd = m_blockchain.get_txpool_tx_blob(txid);
txs.push_back(std::make_pair(txid, bd));
}
catch (const std::exception &e)
{
MERROR("Failed to get transaction blob from db");
// ignore error
}
}
}
return true;
}, false);
return true;
}
//---------------------------------------------------------------------------------
void tx_memory_pool::set_relayed(const std::list<std::pair<crypto::hash, cryptonote::blobdata>> &txs)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
const time_t now = time(NULL);
LockedTXN lock(m_blockchain);
for (auto it = txs.begin(); it != txs.end(); ++it)
{
try
{
txpool_tx_meta_t meta;
if (m_blockchain.get_txpool_tx_meta(it->first, meta))
{
meta.relayed = true;
meta.last_relayed_time = now;
m_blockchain.update_txpool_tx(it->first, meta);
}
}
catch (const std::exception &e)
{
MERROR("Failed to update txpool transaction metadata: " << e.what());
// continue
}
}
}
//---------------------------------------------------------------------------------
size_t tx_memory_pool::get_transactions_count(bool include_unrelayed_txes) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
return m_blockchain.get_txpool_tx_count(include_unrelayed_txes);
}
//---------------------------------------------------------------------------------
void tx_memory_pool::get_transactions(std::list<transaction>& txs, bool include_unrelayed_txes) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
m_blockchain.for_all_txpool_txes([&txs](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
transaction tx;
if (!parse_and_validate_tx_from_blob(*bd, tx))
{
MERROR("Failed to parse tx from txpool");
// continue
return true;
}
txs.push_back(tx);
return true;
}, true, include_unrelayed_txes);
}
//------------------------------------------------------------------
void tx_memory_pool::get_transaction_hashes(std::vector<crypto::hash>& txs, bool include_unrelayed_txes) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
m_blockchain.for_all_txpool_txes([&txs](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
txs.push_back(txid);
return true;
}, false, include_unrelayed_txes);
}
//------------------------------------------------------------------
void tx_memory_pool::get_transaction_backlog(std::vector<tx_backlog_entry>& backlog, bool include_unrelayed_txes) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
const uint64_t now = time(NULL);
m_blockchain.for_all_txpool_txes([&backlog, now](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
backlog.push_back({meta.blob_size, meta.fee, meta.receive_time - now});
return true;
}, false, include_unrelayed_txes);
}
//------------------------------------------------------------------
void tx_memory_pool::get_transaction_stats(struct txpool_stats& stats, bool include_unrelayed_txes) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
const uint64_t now = time(NULL);
std::map<uint64_t, txpool_histo> agebytes;
stats.txs_total = m_blockchain.get_txpool_tx_count(include_unrelayed_txes);
std::vector<uint32_t> sizes;
sizes.reserve(stats.txs_total);
m_blockchain.for_all_txpool_txes([&stats, &sizes, now, &agebytes](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
sizes.push_back(meta.blob_size);
stats.bytes_total += meta.blob_size;
if (!stats.bytes_min || meta.blob_size < stats.bytes_min)
stats.bytes_min = meta.blob_size;
if (meta.blob_size > stats.bytes_max)
stats.bytes_max = meta.blob_size;
if (!meta.relayed)
stats.num_not_relayed++;
stats.fee_total += meta.fee;
if (!stats.oldest || meta.receive_time < stats.oldest)
stats.oldest = meta.receive_time;
if (meta.receive_time < now - 600)
stats.num_10m++;
if (meta.last_failed_height)
stats.num_failing++;
uint64_t age = now - meta.receive_time + (now == meta.receive_time);
agebytes[age].txs++;
agebytes[age].bytes += meta.blob_size;
if (meta.double_spend_seen)
++stats.num_double_spends;
return true;
}, false, include_unrelayed_txes);
stats.bytes_med = epee::misc_utils::median(sizes);
if (stats.txs_total > 1)
{
/* looking for 98th percentile */
size_t end = stats.txs_total * 0.02;
uint64_t delta, factor;
std::map<uint64_t, txpool_histo>::iterator it, i2;
if (end)
{
/* If enough txs, spread the first 98% of results across
* the first 9 bins, drop final 2% in last bin.
*/
it=agebytes.end();
for (size_t n=0; n <= end; n++, it--);
stats.histo_98pc = it->first;
factor = 9;
delta = it->first;
stats.histo.resize(10);
} else
{
/* If not enough txs, don't reserve the last slot;
* spread evenly across all 10 bins.
*/
stats.histo_98pc = 0;
it = agebytes.end();
factor = stats.txs_total > 9 ? 10 : stats.txs_total;
delta = now - stats.oldest;
stats.histo.resize(factor);
}
if (!delta)
delta = 1;
for (i2 = agebytes.begin(); i2 != it; i2++)
{
size_t i = (i2->first * factor - 1) / delta;
stats.histo[i].txs += i2->second.txs;
stats.histo[i].bytes += i2->second.bytes;
}
for (; i2 != agebytes.end(); i2++)
{
stats.histo[factor].txs += i2->second.txs;
stats.histo[factor].bytes += i2->second.bytes;
}
}
}
//------------------------------------------------------------------
//TODO: investigate whether boolean return is appropriate
bool tx_memory_pool::get_transactions_and_spent_keys_info(std::vector<tx_info>& tx_infos, std::vector<spent_key_image_info>& key_image_infos, bool include_sensitive_data) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
m_blockchain.for_all_txpool_txes([&tx_infos, key_image_infos, include_sensitive_data](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
tx_info txi;
txi.id_hash = epee::string_tools::pod_to_hex(txid);
txi.tx_blob = *bd;
transaction tx;
if (!parse_and_validate_tx_from_blob(*bd, tx))
{
MERROR("Failed to parse tx from txpool");
// continue
return true;
}
txi.tx_json = obj_to_json_str(tx);
txi.blob_size = meta.blob_size;
txi.fee = meta.fee;
txi.kept_by_block = meta.kept_by_block;
txi.max_used_block_height = meta.max_used_block_height;
txi.max_used_block_id_hash = epee::string_tools::pod_to_hex(meta.max_used_block_id);
txi.last_failed_height = meta.last_failed_height;
txi.last_failed_id_hash = epee::string_tools::pod_to_hex(meta.last_failed_id);
// In restricted mode we do not include this data:
txi.receive_time = include_sensitive_data ? meta.receive_time : 0;
txi.relayed = meta.relayed;
// In restricted mode we do not include this data:
txi.last_relayed_time = include_sensitive_data ? meta.last_relayed_time : 0;
txi.do_not_relay = meta.do_not_relay;
txi.double_spend_seen = meta.double_spend_seen;
tx_infos.push_back(txi);
return true;
}, true, include_sensitive_data);
txpool_tx_meta_t meta;
for (const key_images_container::value_type& kee : m_spent_key_images) {
const crypto::key_image& k_image = kee.first;
const std::unordered_set<crypto::hash>& kei_image_set = kee.second;
spent_key_image_info ki;
ki.id_hash = epee::string_tools::pod_to_hex(k_image);
for (const crypto::hash& tx_id_hash : kei_image_set)
{
if (!include_sensitive_data)
{
try
{
if (!m_blockchain.get_txpool_tx_meta(tx_id_hash, meta))
{
MERROR("Failed to get tx meta from txpool");
return false;
}
if (!meta.relayed)
// Do not include that transaction if in restricted mode and it's not relayed
continue;
}
catch (const std::exception &e)
{
MERROR("Failed to get tx meta from txpool: " << e.what());
return false;
}
}
ki.txs_hashes.push_back(epee::string_tools::pod_to_hex(tx_id_hash));
}
// Only return key images for which we have at least one tx that we can show for them
if (!ki.txs_hashes.empty())
key_image_infos.push_back(ki);
}
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::get_pool_for_rpc(std::vector<cryptonote::rpc::tx_in_pool>& tx_infos, cryptonote::rpc::key_images_with_tx_hashes& key_image_infos) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
m_blockchain.for_all_txpool_txes([&tx_infos, key_image_infos](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd){
cryptonote::rpc::tx_in_pool txi;
txi.tx_hash = txid;
transaction tx;
if (!parse_and_validate_tx_from_blob(*bd, tx))
{
MERROR("Failed to parse tx from txpool");
// continue
return true;
}
txi.tx = tx;
txi.blob_size = meta.blob_size;
txi.fee = meta.fee;
txi.kept_by_block = meta.kept_by_block;
txi.max_used_block_height = meta.max_used_block_height;
txi.max_used_block_hash = meta.max_used_block_id;
txi.last_failed_block_height = meta.last_failed_height;
txi.last_failed_block_hash = meta.last_failed_id;
txi.receive_time = meta.receive_time;
txi.relayed = meta.relayed;
txi.last_relayed_time = meta.last_relayed_time;
txi.do_not_relay = meta.do_not_relay;
txi.double_spend_seen = meta.double_spend_seen;
tx_infos.push_back(txi);
return true;
}, true, false);
for (const key_images_container::value_type& kee : m_spent_key_images) {
std::vector<crypto::hash> tx_hashes;
const std::unordered_set<crypto::hash>& kei_image_set = kee.second;
for (const crypto::hash& tx_id_hash : kei_image_set)
{
tx_hashes.push_back(tx_id_hash);
}
const crypto::key_image& k_image = kee.first;
key_image_infos[k_image] = tx_hashes;
}
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::check_for_key_images(const std::vector<crypto::key_image>& key_images, std::vector<bool> spent) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
spent.clear();
for (const auto& image : key_images)
{
spent.push_back(m_spent_key_images.find(image) == m_spent_key_images.end() ? false : true);
}
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::get_transaction(const crypto::hash& id, cryptonote::blobdata& txblob) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
try
{
return m_blockchain.get_txpool_tx_blob(id, txblob);
}
catch (const std::exception &e)
{
return false;
}
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::on_blockchain_inc(uint64_t new_block_height, const crypto::hash& top_block_id)
{
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::on_blockchain_dec(uint64_t new_block_height, const crypto::hash& top_block_id)
{
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::have_tx(const crypto::hash &id) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
return m_blockchain.get_db().txpool_has_tx(id);
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::have_tx_keyimges_as_spent(const transaction& tx) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
for(const auto& in: tx.vin)
{
CHECKED_GET_SPECIFIC_VARIANT(in, const txin_to_key, tokey_in, true);//should never fail
if(have_tx_keyimg_as_spent(tokey_in.k_image))
return true;
}
return false;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::have_tx_keyimg_as_spent(const crypto::key_image& key_im) const
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
return m_spent_key_images.end() != m_spent_key_images.find(key_im);
}
//---------------------------------------------------------------------------------
void tx_memory_pool::lock() const
{
m_transactions_lock.lock();
}
//---------------------------------------------------------------------------------
void tx_memory_pool::unlock() const
{
m_transactions_lock.unlock();
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::is_transaction_ready_to_go(txpool_tx_meta_t& txd, transaction &tx) const
{
//not the best implementation at this time, sorry :(
//check is ring_signature already checked ?
if(txd.max_used_block_id == null_hash)
{//not checked, lets try to check
if(txd.last_failed_id != null_hash && m_blockchain.get_current_blockchain_height() > txd.last_failed_height && txd.last_failed_id == m_blockchain.get_block_id_by_height(txd.last_failed_height))
return false;//we already sure that this tx is broken for this height
tx_verification_context tvc;
if(!m_blockchain.check_tx_inputs(tx, txd.max_used_block_height, txd.max_used_block_id, tvc))
{
txd.last_failed_height = m_blockchain.get_current_blockchain_height()-1;
txd.last_failed_id = m_blockchain.get_block_id_by_height(txd.last_failed_height);
return false;
}
}else
{
if(txd.max_used_block_height >= m_blockchain.get_current_blockchain_height())
return false;
if(true)
{
//if we already failed on this height and id, skip actual ring signature check
if(txd.last_failed_id == m_blockchain.get_block_id_by_height(txd.last_failed_height))
return false;
//check ring signature again, it is possible (with very small chance) that this transaction become again valid
tx_verification_context tvc;
if(!m_blockchain.check_tx_inputs(tx, txd.max_used_block_height, txd.max_used_block_id, tvc))
{
txd.last_failed_height = m_blockchain.get_current_blockchain_height()-1;
txd.last_failed_id = m_blockchain.get_block_id_by_height(txd.last_failed_height);
return false;
}
}
}
//if we here, transaction seems valid, but, anyway, check for key_images collisions with blockchain, just to be sure
if(m_blockchain.have_tx_keyimges_as_spent(tx))
{
txd.double_spend_seen = true;
return false;
}
//transaction is ok.
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::have_key_images(const std::unordered_set<crypto::key_image>& k_images, const transaction& tx)
{
for(size_t i = 0; i!= tx.vin.size(); i++)
{
CHECKED_GET_SPECIFIC_VARIANT(tx.vin[i], const txin_to_key, itk, false);
if(k_images.count(itk.k_image))
return true;
}
return false;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::append_key_images(std::unordered_set<crypto::key_image>& k_images, const transaction& tx)
{
for(size_t i = 0; i!= tx.vin.size(); i++)
{
CHECKED_GET_SPECIFIC_VARIANT(tx.vin[i], const txin_to_key, itk, false);
auto i_res = k_images.insert(itk.k_image);
CHECK_AND_ASSERT_MES(i_res.second, false, "internal error: key images pool cache - inserted duplicate image in set: " << itk.k_image);
}
return true;
}
//---------------------------------------------------------------------------------
void tx_memory_pool::mark_double_spend(const transaction &tx)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
LockedTXN lock(m_blockchain);
for(size_t i = 0; i!= tx.vin.size(); i++)
{
CHECKED_GET_SPECIFIC_VARIANT(tx.vin[i], const txin_to_key, itk, void());
const key_images_container::const_iterator it = m_spent_key_images.find(itk.k_image);
if (it != m_spent_key_images.end())
{
for (const crypto::hash &txid: it->second)
{
txpool_tx_meta_t meta;
if (!m_blockchain.get_txpool_tx_meta(txid, meta))
{
MERROR("Failed to find tx meta in txpool");
// continue, not fatal
continue;
}
if (!meta.double_spend_seen)
{
MDEBUG("Marking " << txid << " as double spending " << itk.k_image);
meta.double_spend_seen = true;
try
{
m_blockchain.update_txpool_tx(txid, meta);
}
catch (const std::exception &e)
{
MERROR("Failed to update tx meta: " << e.what());
// continue, not fatal
}
}
}
}
}
}
//---------------------------------------------------------------------------------
std::string tx_memory_pool::print_pool(bool short_format) const
{
std::stringstream ss;
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
m_blockchain.for_all_txpool_txes([&ss, short_format](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *txblob) {
ss << "id: " << txid << std::endl;
if (!short_format) {
cryptonote::transaction tx;
if (!parse_and_validate_tx_from_blob(*txblob, tx))
{
MERROR("Failed to parse tx from txpool");
return true; // continue
}
ss << obj_to_json_str(tx) << std::endl;
}
ss << "blob_size: " << meta.blob_size << std::endl
<< "fee: " << print_money(meta.fee) << std::endl
<< "kept_by_block: " << (meta.kept_by_block ? 'T' : 'F') << std::endl
<< "double_spend_seen: " << (meta.double_spend_seen ? 'T' : 'F') << std::endl
<< "max_used_block_height: " << meta.max_used_block_height << std::endl
<< "max_used_block_id: " << meta.max_used_block_id << std::endl
<< "last_failed_height: " << meta.last_failed_height << std::endl
<< "last_failed_id: " << meta.last_failed_id << std::endl;
return true;
}, !short_format);
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, uint64_t &expected_reward, uint8_t version)
{
// Warning: This function takes already_generated_
// coins as an argument and appears to do nothing
// with it.
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
uint64_t best_coinbase = 0, coinbase = 0;
total_size = 0;
fee = 0;
//baseline empty block
get_block_reward(median_size, total_size, already_generated_coins, best_coinbase, version);
size_t max_total_size_pre_v5 = (130 * median_size) / 100 - CRYPTONOTE_COINBASE_BLOB_RESERVED_SIZE;
size_t max_total_size_v5 = 2 * median_size - CRYPTONOTE_COINBASE_BLOB_RESERVED_SIZE;
size_t max_total_size = version >= 5 ? max_total_size_v5 : max_total_size_pre_v5;
std::unordered_set<crypto::key_image> k_images;
LOG_PRINT_L2("Filling block template, median size " << median_size << ", " << m_txs_by_fee_and_receive_time.size() << " txes in the pool");
LockedTXN lock(m_blockchain);
auto sorted_it = m_txs_by_fee_and_receive_time.begin();
while (sorted_it != m_txs_by_fee_and_receive_time.end())
{
txpool_tx_meta_t meta;
if (!m_blockchain.get_txpool_tx_meta(sorted_it->second, meta))
{
MERROR(" failed to find tx meta");
continue;
}
LOG_PRINT_L2("Considering " << sorted_it->second << ", size " << meta.blob_size << ", current block size " << total_size << "/" << max_total_size << ", current coinbase " << print_money(best_coinbase));
// Can not exceed maximum block size
if (max_total_size < total_size + meta.blob_size)
{
LOG_PRINT_L2(" would exceed maximum block size");
sorted_it++;
continue;
}
// start using the optimal filling algorithm from v5
if (version >= 5)
{
// If we're getting lower coinbase tx,
// stop including more tx
uint64_t block_reward;
if(!get_block_reward(median_size, total_size + meta.blob_size, already_generated_coins, block_reward, version))
{
LOG_PRINT_L2(" would exceed maximum block size");
sorted_it++;
continue;
}
coinbase = block_reward + fee + meta.fee;
if (coinbase < template_accept_threshold(best_coinbase))
{
LOG_PRINT_L2(" would decrease coinbase to " << print_money(coinbase));
sorted_it++;
continue;
}
}
else
{
// If we've exceeded the penalty free size,
// stop including more tx
if (total_size > median_size)
{
LOG_PRINT_L2(" would exceed median block size");
break;
}
}
cryptonote::blobdata txblob = m_blockchain.get_txpool_tx_blob(sorted_it->second);
cryptonote::transaction tx;
if (!parse_and_validate_tx_from_blob(txblob, tx))
{
MERROR("Failed to parse tx from txpool");
sorted_it++;
continue;
}
// Skip transactions that are not ready to be
// included into the blockchain or that are
// missing key images
const cryptonote::txpool_tx_meta_t original_meta = meta;
bool ready = is_transaction_ready_to_go(meta, tx);
if (memcmp(&original_meta, &meta, sizeof(meta)))
{
try
{
m_blockchain.update_txpool_tx(sorted_it->second, meta);
}
catch (const std::exception &e)
{
MERROR("Failed to update tx meta: " << e.what());
// continue, not fatal
}
}
if (!ready)
{
LOG_PRINT_L2(" not ready to go");
sorted_it++;
continue;
}
if (have_key_images(k_images, tx))
{
LOG_PRINT_L2(" key images already seen");
sorted_it++;
continue;
}
bl.tx_hashes.push_back(sorted_it->second);
total_size += meta.blob_size;
fee += meta.fee;
best_coinbase = coinbase;
append_key_images(k_images, tx);
sorted_it++;
LOG_PRINT_L2(" added, new block size " << total_size << "/" << max_total_size << ", coinbase " << print_money(best_coinbase));
}
expected_reward = best_coinbase;
LOG_PRINT_L2("Block template filled with " << bl.tx_hashes.size() << " txes, size "
<< total_size << "/" << max_total_size << ", coinbase " << print_money(best_coinbase)
<< " (including " << print_money(fee) << " in fees)");
return true;
}
//---------------------------------------------------------------------------------
size_t tx_memory_pool::validate(uint8_t version)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
size_t tx_size_limit = get_transaction_size_limit(version);
std::unordered_set<crypto::hash> remove;
m_txpool_size = 0;
m_blockchain.for_all_txpool_txes([this, &remove, tx_size_limit](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata*) {
m_txpool_size += meta.blob_size;
if (meta.blob_size > tx_size_limit) {
LOG_PRINT_L1("Transaction " << txid << " is too big (" << meta.blob_size << " bytes), removing it from pool");
remove.insert(txid);
}
else if (m_blockchain.have_tx(txid)) {
LOG_PRINT_L1("Transaction " << txid << " is in the blockchain, removing it from pool");
remove.insert(txid);
}
return true;
}, false);
size_t n_removed = 0;
if (!remove.empty())
{
LockedTXN lock(m_blockchain);
for (const crypto::hash &txid: remove)
{
try
{
cryptonote::blobdata txblob = m_blockchain.get_txpool_tx_blob(txid);
cryptonote::transaction tx;
if (!parse_and_validate_tx_from_blob(txblob, tx))
{
MERROR("Failed to parse tx from txpool");
continue;
}
// remove tx from db first
m_blockchain.remove_txpool_tx(txid);
m_txpool_size -= txblob.size();
remove_transaction_keyimages(tx);
auto sorted_it = find_tx_in_sorted_container(txid);
if (sorted_it == m_txs_by_fee_and_receive_time.end())
{
LOG_PRINT_L1("Removing tx " << txid << " from tx pool, but it was not found in the sorted txs container!");
}
else
{
m_txs_by_fee_and_receive_time.erase(sorted_it);
}
++n_removed;
}
catch (const std::exception &e)
{
MERROR("Failed to remove invalid tx from pool");
// continue
}
}
}
return n_removed;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::init(size_t max_txpool_size)
{
CRITICAL_REGION_LOCAL(m_transactions_lock);
CRITICAL_REGION_LOCAL1(m_blockchain);
m_txpool_max_size = max_txpool_size ? max_txpool_size : DEFAULT_TXPOOL_MAX_SIZE;
m_txs_by_fee_and_receive_time.clear();
m_spent_key_images.clear();
m_txpool_size = 0;
std::vector<crypto::hash> remove;
// first add the not kept by block, then the kept by block,
// to avoid rejection due to key image collision
for (int pass = 0; pass < 2; ++pass)
{
const bool kept = pass == 1;
bool r = m_blockchain.for_all_txpool_txes([this, &remove, kept](const crypto::hash &txid, const txpool_tx_meta_t &meta, const cryptonote::blobdata *bd) {
if (!!kept != !!meta.kept_by_block)
return true;
cryptonote::transaction tx;
if (!parse_and_validate_tx_from_blob(*bd, tx))
{
MWARNING("Failed to parse tx from txpool, removing");
remove.push_back(txid);
}
if (!insert_key_images(tx, meta.kept_by_block))
{
MFATAL("Failed to insert key images from txpool tx");
return false;
}
m_txs_by_fee_and_receive_time.emplace(std::pair<double, time_t>(meta.fee / (double)meta.blob_size, meta.receive_time), txid);
m_txpool_size += meta.blob_size;
return true;
}, true);
if (!r)
return false;
}
if (!remove.empty())
{
LockedTXN lock(m_blockchain);
for (const auto &txid: remove)
{
try
{
m_blockchain.remove_txpool_tx(txid);
}
catch (const std::exception &e)
{
MWARNING("Failed to remove corrupt transaction: " << txid);
// ignore error
}
}
}
return true;
}
//---------------------------------------------------------------------------------
bool tx_memory_pool::deinit()
{
return true;
}
}
Reference in New Issue View Git Blame Copy Permalink