onchaind: resolve HTLC transactions.

When we sent out an HTLC-Timeout or HTLC-Success tx, we need to spend
it after the timeout so it's safely in our wallet.

We generalize the tx_type OUR_UNILATERAL_TO_US_RETURN_TO_WALLET to
OUR_DELAYED_RETURN_TO_WALLET, since we use it for HTLC transactions too.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Rusty Russell 2017-09-20 14:24:16 +09:30
parent a76a53a933
commit f96a04e2a6
3 changed files with 85 additions and 22 deletions

View File

@ -502,8 +502,55 @@ static void handle_htlc_onchain_fulfill(struct tracked_output *out,
status_failed(STATUS_FAIL_INTERNAL_ERROR, "FIXME: %s", __func__);
}
static void resolve_htlc_tx(struct tracked_output ***outs,
size_t out_index,
const struct bitcoin_tx *htlc_tx,
const struct sha256_double *htlc_txid,
u32 tx_blockheight)
{
struct tracked_output *out;
struct bitcoin_tx *tx;
u8 *wscript = bitcoin_wscript_htlc_tx(htlc_tx, to_self_delay[LOCAL],
&keyset->self_revocation_key,
&keyset->self_delayed_payment_key);
/* BOLT #5:
*
* A node SHOULD resolve its own HTLC transaction output by spending
* it to a convenient address. A node MUST wait until the
* `OP_CHECKSEQUENCEVERIFY` delay has passed (as specified by the
* other node's `open_channel` `to_self_delay` field) before spending
* the output.
*/
out = new_tracked_output(outs, htlc_txid, tx_blockheight,
(*outs)[out_index]->resolved->tx_type,
0, htlc_tx->output[0].amount,
DELAYED_OUTPUT_TO_US,
NULL, NULL, NULL);
/* BOLT #3:
*
* ## HTLC-Timeout and HTLC-Success Transactions
*
* These HTLC transactions are almost identical, except the
* HTLC-Timeout transaction is timelocked.
*
* ... to collect the output the local node uses an input with
* nSequence `to_self_delay` and a witness stack `<local_delayedsig>
* 0`
*/
tx = tx_to_us(*outs, out, to_self_delay[LOCAL], 0, NULL, 0,
wscript,
&delayed_payment_privkey,
&keyset->self_delayed_payment_key);
propose_resolution(out, tx, to_self_delay[LOCAL],
OUR_DELAYED_RETURN_TO_WALLET);
}
/* An output has been spent: see if it resolves something we care about. */
static void output_spent(struct tracked_output **outs,
static void output_spent(struct tracked_output ***outs,
const struct bitcoin_tx *tx,
u32 input_num,
u32 tx_blockheight)
@ -512,23 +559,30 @@ static void output_spent(struct tracked_output **outs,
bitcoin_txid(tx, &txid);
for (size_t i = 0; i < tal_count(outs); i++) {
if (outs[i]->resolved)
for (size_t i = 0; i < tal_count(*outs); i++) {
struct tracked_output *out = (*outs)[i];
if (out->resolved)
continue;
if (tx->input[input_num].index != outs[i]->outnum)
if (tx->input[input_num].index != out->outnum)
continue;
if (!structeq(&tx->input[input_num].txid, &outs[i]->txid))
if (!structeq(&tx->input[input_num].txid, &out->txid))
continue;
/* Was this our resolution? */
if (resolved_by_proposal(outs[i], &txid))
if (resolved_by_proposal(out, &txid)) {
/* If it's our htlc tx, we need to resolve that, too. */
if (out->resolved->tx_type == OUR_HTLC_SUCCESS_TX
|| out->resolved->tx_type == OUR_HTLC_TIMEOUT_TX)
resolve_htlc_tx(outs, i, tx, &txid,
tx_blockheight);
return;
}
switch (outs[i]->output_type) {
switch (out->output_type) {
case OUTPUT_TO_US:
case DELAYED_OUTPUT_TO_US:
unknown_spend(outs[i], tx);
unknown_spend(out, tx);
break;
case THEIR_HTLC:
@ -538,7 +592,7 @@ static void output_spent(struct tracked_output **outs,
case OUR_HTLC:
/* The only way they can spend this: fulfill */
handle_htlc_onchain_fulfill(outs[i], tx);
handle_htlc_onchain_fulfill(out, tx);
break;
case FUNDING_OUTPUT:
@ -552,8 +606,8 @@ static void output_spent(struct tracked_output **outs,
case DELAYED_OUTPUT_TO_THEM:
status_failed(STATUS_FAIL_INTERNAL_ERROR,
"Tracked spend of %s/%s?",
tx_type_name(outs[i]->tx_type),
output_type_name(outs[i]->output_type));
tx_type_name(out->tx_type),
output_type_name(out->output_type));
}
return;
}
@ -703,7 +757,7 @@ static void wait_for_resolved(struct tracked_output **outs)
tx_new_depth(outs, &txid, depth);
else if (fromwire_onchain_spent(msg, NULL, tx, &input_num,
&tx_blockheight))
output_spent(outs, tx, input_num, tx_blockheight);
output_spent(&outs, tx, input_num, tx_blockheight);
else if (fromwire_onchain_known_preimage(msg, NULL, &preimage))
handle_preimage(outs, &preimage);
else
@ -1033,7 +1087,7 @@ static void handle_our_unilateral(const struct bitcoin_tx *tx,
* If the output is spent (as recommended), the output
* is *resolved* by the spending transaction */
propose_resolution(out, to_us, to_self_delay[LOCAL],
OUR_UNILATERAL_TO_US_RETURN_TO_WALLET);
OUR_DELAYED_RETURN_TO_WALLET);
script[LOCAL] = NULL;
continue;

View File

@ -26,8 +26,8 @@ enum tx_type {
OUR_HTLC_TIMEOUT_TX,
OUR_HTLC_SUCCESS_TX,
/* When we spend the to-us output (after cltv_expiry) */
OUR_UNILATERAL_TO_US_RETURN_TO_WALLET,
/* When we spend a delayed output (after cltv_expiry) */
OUR_DELAYED_RETURN_TO_WALLET,
/* Special type for marking outputs as resolved by self. */
SELF,
@ -45,7 +45,7 @@ enum output_type {
OUTPUT_TO_US,
DELAYED_OUTPUT_TO_THEM,
/* OUR_UNILATERAL */
/* OUR_UNILATERAL, or OUR_HTLC_TIMEOUT_TX */
DELAYED_OUTPUT_TO_US,
OUTPUT_TO_THEM,

View File

@ -429,13 +429,13 @@ class LightningDTests(BaseLightningDTests):
l1.daemon.wait_for_log('Their unilateral tx, old commit point')
l1.daemon.wait_for_log('-> ONCHAIND_THEIR_UNILATERAL')
l2.daemon.wait_for_log('-> ONCHAIND_OUR_UNILATERAL')
l2.daemon.wait_for_log('Propose handling OUR_UNILATERAL/DELAYED_OUTPUT_TO_US by OUR_UNILATERAL_TO_US_RETURN_TO_WALLET (.*) in 6 blocks')
l2.daemon.wait_for_log('Propose handling OUR_UNILATERAL/DELAYED_OUTPUT_TO_US by OUR_DELAYED_RETURN_TO_WALLET (.*) in 6 blocks')
# Now, mine 6 blocks so it sends out the spending tx.
bitcoind.rpc.generate(6)
# It should send the to-wallet tx.
l2.daemon.wait_for_log('Broadcasting OUR_UNILATERAL_TO_US_RETURN_TO_WALLET')
l2.daemon.wait_for_log('Broadcasting OUR_DELAYED_RETURN_TO_WALLET')
l2.daemon.wait_for_log('sendrawtx exit 0')
# 100 after l1 sees tx, it should be done.
@ -486,7 +486,7 @@ class LightningDTests(BaseLightningDTests):
l1.daemon.wait_for_log('-> ONCHAIND_THEIR_UNILATERAL')
l2.daemon.wait_for_log('OUR_UNILATERAL/THEIR_HTLC')
# l2 should fulfill HTLC onchain
# l2 should fulfill HTLC onchain, and spend to-us (any order)
l2.daemon.wait_for_log('Propose handling OUR_UNILATERAL/THEIR_HTLC by OUR_HTLC_SUCCESS_TX .* in 0 blocks')
l2.daemon.wait_for_log('sendrawtx exit 0')
@ -495,9 +495,14 @@ class LightningDTests(BaseLightningDTests):
l1.daemon.wait_for_log('FIXME: handle_htlc_onchain_fulfill')
l1.has_failed()
# After 5 more blocks, l2 can spend to-us
l1.bitcoin.rpc.generate(5)
l2.daemon.wait_for_log('Broadcasting OUR_UNILATERAL_TO_US_RETURN_TO_WALLET')
# After 4 more blocks, l2 can spend to-us.
l1.bitcoin.rpc.generate(4)
l2.daemon.wait_for_log('Broadcasting OUR_DELAYED_RETURN_TO_WALLET .* to resolve OUR_UNILATERAL/DELAYED_OUTPUT_TO_US')
l2.daemon.wait_for_log('sendrawtx exit 0')
# One more, HTLC tx is now spentable.
l1.bitcoin.rpc.generate(1)
l2.daemon.wait_for_log('Broadcasting OUR_DELAYED_RETURN_TO_WALLET .* to resolve OUR_HTLC_SUCCESS_TX/DELAYED_OUTPUT_TO_US')
l2.daemon.wait_for_log('sendrawtx exit 0')
# 100 blocks after last spend, l2 should be done.
@ -575,6 +580,10 @@ class LightningDTests(BaseLightningDTests):
bitcoind.rpc.generate(1)
# l1.daemon.wait_for_log('Resolved THEIR_UNILATERAL/OUR_HTLC by our proposal OUR_HTLC_TIMEOUT_TO_US')
l2.daemon.wait_for_log('Propose handling OUR_UNILATERAL/THEIR_HTLC by OUR_HTLC_SUCCESS_TX .* in 0 blocks')
bitcoind.rpc.generate(1)
l2.daemon.wait_for_log('Propose handling OUR_HTLC_SUCCESS_TX/DELAYED_OUTPUT_TO_US by OUR_DELAYED_RETURN_TO_WALLET .* in 6 blocks')
bitcoind.rpc.generate(6)
l2.daemon.wait_for_log('sendrawtx exit 0')
# FIXME: This doesn't work :(
# FIXME: sendpay command should time out!