detect links between channel close and open txs
This commit is contained in:
Mononaut
softsimon
@@ -304,6 +304,233 @@ class NetworkSyncService {
|
||||
logger.err('$scanForClosedChannels() error: ' + (e instanceof Error ? e.message : e));
|
||||
}
|
||||
}
|
||||
|
||||
private findLightningScript(vin: IEsploraApi.Vin): number {
|
||||
const topElement = vin.witness[vin.witness.length - 2];
|
||||
if (/^OP_IF OP_PUSHBYTES_33 \w{66} OP_ELSE OP_PUSH(NUM_\d+|BYTES_(1 \w{2}|2 \w{4})) OP_CSV OP_DROP OP_PUSHBYTES_33 \w{66} OP_ENDIF OP_CHECKSIG$/.test(vin.inner_witnessscript_asm)) {
|
||||
// https://github.com/lightning/bolts/blob/master/03-transactions.md#commitment-transaction-outputs
|
||||
if (topElement === '01') {
|
||||
// top element is '01' to get in the revocation path
|
||||
// 'Revoked Lightning Force Close';
|
||||
// Penalty force closed
|
||||
return 2;
|
||||
} else {
|
||||
// top element is '', this is a delayed to_local output
|
||||
// 'Lightning Force Close';
|
||||
return 3;
|
||||
}
|
||||
} else if (
|
||||
/^OP_DUP OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUAL OP_IF OP_CHECKSIG OP_ELSE OP_PUSHBYTES_33 \w{66} OP_SWAP OP_SIZE OP_PUSHBYTES_1 20 OP_EQUAL OP_NOTIF OP_DROP OP_PUSHNUM_2 OP_SWAP OP_PUSHBYTES_33 \w{66} OP_PUSHNUM_2 OP_CHECKMULTISIG OP_ELSE OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUALVERIFY OP_CHECKSIG OP_ENDIF (OP_PUSHNUM_1 OP_CSV OP_DROP |)OP_ENDIF$/.test(vin.inner_witnessscript_asm) ||
|
||||
/^OP_DUP OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUAL OP_IF OP_CHECKSIG OP_ELSE OP_PUSHBYTES_33 \w{66} OP_SWAP OP_SIZE OP_PUSHBYTES_1 20 OP_EQUAL OP_IF OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUALVERIFY OP_PUSHNUM_2 OP_SWAP OP_PUSHBYTES_33 \w{66} OP_PUSHNUM_2 OP_CHECKMULTISIG OP_ELSE OP_DROP OP_PUSHBYTES_3 \w{6} OP_CLTV OP_DROP OP_CHECKSIG OP_ENDIF (OP_PUSHNUM_1 OP_CSV OP_DROP |)OP_ENDIF$/.test(vin.inner_witnessscript_asm)
|
||||
) {
|
||||
// https://github.com/lightning/bolts/blob/master/03-transactions.md#offered-htlc-outputs
|
||||
// https://github.com/lightning/bolts/blob/master/03-transactions.md#received-htlc-outputs
|
||||
if (topElement.length === 66) {
|
||||
// top element is a public key
|
||||
// 'Revoked Lightning HTLC'; Penalty force closed
|
||||
return 4;
|
||||
} else if (topElement) {
|
||||
// top element is a preimage
|
||||
// 'Lightning HTLC';
|
||||
return 5;
|
||||
} else {
|
||||
// top element is '' to get in the expiry of the script
|
||||
// 'Expired Lightning HTLC';
|
||||
return 6;
|
||||
}
|
||||
} else if (/^OP_PUSHBYTES_33 \w{66} OP_CHECKSIG OP_IFDUP OP_NOTIF OP_PUSHNUM_16 OP_CSV OP_ENDIF$/.test(vin.inner_witnessscript_asm)) {
|
||||
// https://github.com/lightning/bolts/blob/master/03-transactions.md#to_local_anchor-and-to_remote_anchor-output-option_anchors
|
||||
if (topElement) {
|
||||
// top element is a signature
|
||||
// 'Lightning Anchor';
|
||||
return 7;
|
||||
} else {
|
||||
// top element is '', it has been swept after 16 blocks
|
||||
// 'Swept Lightning Anchor';
|
||||
return 8;
|
||||
}
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
// If a channel open tx spends funds from a closed channel output,
|
||||
// we can attribute that output to a specific counterparty
|
||||
private async $runOpenedChannelsForensics(): Promise<void> {
|
||||
let progress = 0;
|
||||
|
||||
try {
|
||||
logger.info(`Started running open channel forensics...`);
|
||||
const channels = await channelsApi.$getChannelsWithoutSourceChecked();
|
||||
|
||||
for (const openChannel of channels) {
|
||||
const openTx = await bitcoinApi.$getRawTransaction(openChannel.transaction_id);
|
||||
for (const input of openTx.vin) {
|
||||
const closeChannel = await channelsApi.$getChannelForensicsByTransactionId(input.txid);
|
||||
if (closeChannel) {
|
||||
// this input directly spends a channel close output
|
||||
await this.$attributeChannelBalances(closeChannel, openChannel, input);
|
||||
} else {
|
||||
// check if this input spends any swept channel close outputs
|
||||
await this.$attributeSweptChannelCloses(openChannel, input);
|
||||
}
|
||||
}
|
||||
// calculate how much of the total input value is attributable to the channel open output
|
||||
openChannel.funding_ratio = openTx.vout[openChannel.transaction_vout].value / ((openTx.vout.reduce((sum, v) => sum + v.value, 0) || 1) + openTx.fee);
|
||||
// save changes to the opening channel, and mark it as checked
|
||||
if (openTx.vin.length === 1) {
|
||||
openChannel.single_funded = true;
|
||||
}
|
||||
await channelsApi.$updateOpeningInfo(openChannel);
|
||||
await channelsApi.$markChannelSourceChecked(openChannel.id);
|
||||
|
||||
++progress;
|
||||
const elapsedSeconds = Math.round((new Date().getTime() / 1000) - this.loggerTimer);
|
||||
if (elapsedSeconds > 10) {
|
||||
logger.info(`Updating channel opened channel forensics ${progress}/${channels.length}`);
|
||||
this.loggerTimer = new Date().getTime() / 1000;
|
||||
}
|
||||
}
|
||||
|
||||
logger.info(`Open channels forensics scan complete.`);
|
||||
} catch (e) {
|
||||
logger.err('$runOpenedChannelsForensics() error: ' + (e instanceof Error ? e.message : e));
|
||||
}
|
||||
}
|
||||
|
||||
// Check if a channel open tx input spends the result of a swept channel close output
|
||||
private async $attributeSweptChannelCloses(openChannel: ILightningApi.Channel, input: IEsploraApi.Vin): Promise<void> {
|
||||
const sweepTx = await bitcoinApi.$getRawTransaction(input.txid);
|
||||
if (!sweepTx) {
|
||||
logger.err(`couldn't find input transaction for channel forensics ${openChannel.channel_id} ${input.txid}`);
|
||||
return;
|
||||
}
|
||||
const openContribution = sweepTx.vout[input.vout].value;
|
||||
for (const sweepInput of sweepTx.vin) {
|
||||
const lnScriptType = this.findLightningScript(sweepInput);
|
||||
if (lnScriptType > 1) {
|
||||
const closeChannel = await channelsApi.$getChannelForensicsByTransactionId(sweepInput.txid);
|
||||
if (closeChannel) {
|
||||
const initiator = (lnScriptType === 2 || lnScriptType === 4) ? 'remote' : (lnScriptType === 3 ? 'local' : null);
|
||||
await this.$attributeChannelBalances(closeChannel, openChannel, sweepInput, openContribution, initiator);
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
private async $attributeChannelBalances(
|
||||
closeChannel, openChannel, input: IEsploraApi.Vin, openContribution: number | null = null,
|
||||
initiator: 'remote' | 'local' | null = null
|
||||
): Promise<void> {
|
||||
// figure out which node controls the input/output
|
||||
let openSide;
|
||||
let closeLocal;
|
||||
let closeRemote;
|
||||
let matched = false;
|
||||
let ambiguous = false; // if counterparties are the same in both channels, we can't tell them apart
|
||||
if (openChannel.node1_public_key === closeChannel.node1_public_key) {
|
||||
openSide = 1;
|
||||
closeLocal = 1;
|
||||
closeRemote = 2;
|
||||
matched = true;
|
||||
} else if (openChannel.node1_public_key === closeChannel.node2_public_key) {
|
||||
openSide = 1;
|
||||
closeLocal = 2;
|
||||
closeRemote = 1;
|
||||
matched = true;
|
||||
}
|
||||
if (openChannel.node2_public_key === closeChannel.node1_public_key) {
|
||||
openSide = 2;
|
||||
closeLocal = 1;
|
||||
closeRemote = 2;
|
||||
if (matched) {
|
||||
ambiguous = true;
|
||||
}
|
||||
matched = true;
|
||||
} else if (openChannel.node2_public_key === closeChannel.node2_public_key) {
|
||||
openSide = 2;
|
||||
closeLocal = 2;
|
||||
closeRemote = 1;
|
||||
if (matched) {
|
||||
ambiguous = true;
|
||||
}
|
||||
matched = true;
|
||||
}
|
||||
|
||||
if (matched && !ambiguous) {
|
||||
// fetch closing channel transaction and perform forensics on the outputs
|
||||
let closingTx: IEsploraApi.Transaction | undefined;
|
||||
let outspends: IEsploraApi.Outspend[] | undefined;
|
||||
try {
|
||||
closingTx = await bitcoinApi.$getRawTransaction(input.txid);
|
||||
outspends = await bitcoinApi.$getOutspends(input.txid);
|
||||
} catch (e) {
|
||||
logger.err(`Failed to call ${config.ESPLORA.REST_API_URL + '/tx/' + closeChannel.closing_transaction_id + '/outspends'}. Reason ${e instanceof Error ? e.message : e}`);
|
||||
}
|
||||
if (!outspends || !closingTx) {
|
||||
return;
|
||||
}
|
||||
if (!closeChannel.outputs) {
|
||||
closeChannel.outputs = closeChannel.outputs || closingTx.vout.map(vout => {
|
||||
return {
|
||||
type: 0,
|
||||
value: vout.value,
|
||||
};
|
||||
});
|
||||
}
|
||||
for (let i = 0; i < outspends.length; i++) {
|
||||
const outspend = outspends[i];
|
||||
const output = closeChannel.outputs[i];
|
||||
if (outspend.spent && outspend.txid) {
|
||||
try {
|
||||
const spendingTx = await bitcoinApi.$getRawTransaction(outspend.txid);
|
||||
if (spendingTx) {
|
||||
output.type = this.findLightningScript(spendingTx.vin[outspend.vin || 0]);
|
||||
}
|
||||
} catch (e) {
|
||||
logger.err(`Failed to call ${config.ESPLORA.REST_API_URL + '/tx/' + outspend.txid}. Reason ${e instanceof Error ? e.message : e}`);
|
||||
}
|
||||
} else {
|
||||
output.type = 0;
|
||||
}
|
||||
}
|
||||
|
||||
// attribute outputs to each counterparty, and sum up total known balances
|
||||
closeChannel.outputs[input.vout].node = closeLocal;
|
||||
const isPenalty = closeChannel.outputs.filter((out) => out.type === 2 || out.type === 4).length > 0;
|
||||
const normalOutput = [1,3].includes(closeChannel.outputs[input.vout].type);
|
||||
let localClosingBalance = 0;
|
||||
let remoteClosingBalance = 0;
|
||||
for (const output of closeChannel.outputs) {
|
||||
if (isPenalty) {
|
||||
// penalty close, so local node takes everything
|
||||
localClosingBalance += output.value;
|
||||
} else if (output.node) {
|
||||
// this output determinstically linked to one of the counterparties
|
||||
if (output.node === closeLocal) {
|
||||
localClosingBalance += output.value;
|
||||
} else {
|
||||
remoteClosingBalance += output.value;
|
||||
}
|
||||
} else if (normalOutput && (output.type === 1 || output.type === 3)) {
|
||||
// local node had one main output, therefore remote node takes the other
|
||||
remoteClosingBalance += output.value;
|
||||
}
|
||||
}
|
||||
|
||||
openChannel[`node${openSide}_funding_balance`] = openChannel[`node${openSide}_funding_balance`] + (openContribution || closingTx?.vout[input.vout]?.value || 0);
|
||||
closeChannel[`node${closeLocal}_closing_balance`] = localClosingBalance;
|
||||
closeChannel[`node${closeRemote}_closing_balance`] = remoteClosingBalance;
|
||||
closeChannel.closing_fee = closingTx.fee;
|
||||
|
||||
if (initiator) {
|
||||
const initiatorSide = initiator === 'remote' ? closeRemote : closeLocal;
|
||||
closeChannel.closed_by = closeChannel[`node${initiatorSide}_public_key`];
|
||||
}
|
||||
|
||||
// save changes to the closing channel
|
||||
await channelsApi.$updateClosingInfo(closeChannel);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
export default new NetworkSyncService();
|
||||
|
||||
Reference in New Issue
Block a user