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Use simpler construction in update from Belcher
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https://bitcointalk.org/index.php?topic=2135429.0
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@pool2win
pool2win committed Aug 20, 2024
1 parent 3961906 commit 47a7d8d
Showing 1 changed file with 90 additions and 50 deletions.
140 changes: 90 additions & 50 deletions lib/contracts/miner-payout-mechanisms/hub_channels.rb
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Original file line number Diff line number Diff line change
Expand Up @@ -23,13 +23,8 @@
@hub_out2 = key :new

@miner1 = key :new
@miner1_revocation_key_for_hub = key :new
@hub_revocation_key_for_miner1 = key :new

@miner2 = key :new

@local_delay = 1008

@hub_preimage = 'beef' * 16
@hub_x = hash160(@hub_preimage)

Expand Down Expand Up @@ -75,34 +70,53 @@
]
end

transition :create_miner1_commitment_txs do
@miner1_commitment_for_hub = transaction inputs: [
{ tx: @miner1_channel_tx,
vout: 0,
script_sig: 'sig:multi(_empty,@miner1)' }
],
outputs: [
{ script: %(OP_IF @miner1_revocation_key_for_hub
OP_ELSE @local_delay OP_CHECKSEQUENCEVERIFY OP_DROP @hub
OP_ENDIF OP_CHECKSIG),
amount: 23.996.sats },
{ descriptor: 'wpkh(@miner1)',
amount: 1.0.sats }
]

@hub_commitment_for_miner1 = transaction inputs: [
{ tx: @miner1_channel_tx,
vout: 0,
script_sig: 'sig:multi(@hub,_empty)' }
],
outputs: [
{ descriptor: 'wpkh(@hub)',
amount: 23.996.sats },
{ script: %(OP_IF @hub_revocation_key_for_miner1
OP_ELSE @local_delay OP_CHECKSEQUENCEVERIFY OP_DROP @miner1
OP_ENDIF OP_CHECKSIG),
amount: 1.0.sats }
]
transition :create_miner1_commitment_tx do
# Partially signed by hub and sent to miner1
@commitment_for_miner1 = transaction inputs: [
{ tx: @miner1_channel_tx,
vout: 0,
script_sig: 'sig:multi(@hub,_empty)' }
],
outputs: [
{ descriptor: 'wpkh(@hub)',
amount: 23.996.sats },
{ policy: 'and(hash160(@hub_x),pk(@miner1))',
amount: 1.0.sats }
]
end

# This payout commitment is signed by hub and sent to miner, so the
# miner has control over their coins. As pool finds more blocks, the
# new payout commitments will have a higher balance, so the miner has
# no incentive to broadcast an older commitment. Therefore, we don't
# need a revocation for these commitments.
transition :create_miner1_payout_commitment do
@payout_miner1 = transaction inputs: [
{ tx: @miner1_channel_tx,
vout: 0,
script_sig: 'sig:multi(@hub,_empty)' }
],
outputs: [
{ descriptor: 'wpkh(@hub)',
amount: 22.996.sats },
{ descriptor: 'wpkh(@miner1)',
amount: 2.0.sats }
]
end

transition :create_miner1_second_commitment_tx do
# Partially signed by hub and sent to miner1
@second_commitment_for_miner1 = transaction inputs: [
{ tx: @miner1_channel_tx,
vout: 0,
script_sig: 'sig:multi(@hub,_empty)' }
],
outputs: [
{ descriptor: 'wpkh(@hub)',
amount: 21.996.sats },
{ policy: 'and(hash160(@hub_x),pk(@miner1))',
amount: 3.0.sats }
]
end

transition :confirm_miner1_channel do
Expand All @@ -124,21 +138,44 @@
confirm transaction: @coop_spend_to_hub

# Miner broadcasts commitment to close channel and can claim coins after timeout.
update_script_sig for_tx: @hub_commitment_for_miner1, at_index: 0, with_script_sig: 'sig:multi(@hub,@miner1)'
broadcast @hub_commitment_for_miner1
confirm transaction: @hub_commitment_for_miner1
update_script_sig for_tx: @payout_miner1, at_index: 0, with_script_sig: 'sig:multi(@hub,@miner1)'
broadcast @payout_miner1
confirm transaction: @payout_miner1
end

transition :hub_spends_revealing_preimage do
@non_coop_spend_by_hub = transaction inputs: [
{ tx: @pool_coinbase, vout: 0, script_sig: 'sig:multi(@hub,@miner1)' }
{ tx: @pool_coinbase,
vout: 0,
script_sig: "@hub_preimage sig:wpkh(@hub_alt) '' '' ''" }
],
outputs: [
{ descriptor: 'wpkh(@hub)', amount: 49.998.sats }
]

broadcast @non_coop_spend_by_hub
confirm transaction: @non_coop_spend_by_hub

# # Miner can claim the @payout_miner1 commitment, but the amount in
# # the new commitment is higher, so the miner claims that instead.
# #
# # Miner now knows the preimage and therefore can claim their coins as well

# First broadcast commitment
update_script_sig for_tx: @second_commitment_for_miner1, at_index: 0, with_script_sig: 'sig:multi(@hub,@miner1)'
broadcast @second_commitment_for_miner1
confirm transaction: @second_commitment_for_miner1

# Then spend the commitment output
@miner_claim_coins = transaction inputs: [
{ tx: @second_commitment_for_miner1,
vout: 1,
script_sig: '@hub_preimage sig:@miner1' }
],
outputs: [
{ descriptor: 'wpkh(@miner1)', amount: 2.999.sats }
]
broadcast @miner_claim_coins
confirm transaction: @miner_claim_coins
end

# The Belcher specification requires that as a block is found, the hub
Expand All @@ -151,19 +188,22 @@
# To see how the DSL help with revoking commitments, see the scripts
# under contracts/lightning directory.

run_transitions :hub_setup,
:create_funding_txs,
:create_miner1_commitment_txs,
:confirm_miner1_channel,
:miner1_finds_block,
:make_coinbase_spendable,
:cooperative_spend_pool_coinbase

# run_transitions :reset,
# :hub_setup,
# run_transitions :hub_setup,
# :create_funding_txs,
# :create_miner1_commitment_txs,
# :create_miner1_commitment_tx,
# :confirm_miner1_channel,
# :miner1_finds_block,
# :make_coinbase_spendable,
# :hub_spends_revealing_preimage
# :create_miner1_payout_commitment,
# :cooperative_spend_pool_coinbase

run_transitions :reset,
:hub_setup,
:create_funding_txs,
:create_miner1_commitment_tx,
:confirm_miner1_channel,
:miner1_finds_block,
:make_coinbase_spendable,
:create_miner1_payout_commitment,
:create_miner1_second_commitment_tx,
:hub_spends_revealing_preimage

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