Git-Mirrors/xmr-btc-swap
1
0
Fork 0
mirror of https://github.com/comit-network/xmr-btc-swap.git synced 2024-10-01 01:45:40 -04:00
Code Issues Packages Projects Releases Wiki Activity

Started to extract some steps

Browse Source 
Tealised that the whole point is for them to be idempotent to be useful
This commit is contained in:
Franck Royer 2020-11-25 16:16:04 +11:00 committed by rishflab
parent 66866f8fbd
commit 437c1cbb80
4 changed files with 143 additions and 141 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

154
swap/src/alice.rs
View File

@ -2,6 +2,7 @@
//! Alice holds XMR and wishes receive BTC.
use self::{amounts::*, message0::*, message1::*, message2::*, message3::*};
use crate::{
alice::execution::{lock_xmr, negotiate},
bitcoin,
bitcoin::{EncryptedSignature, TX_LOCK_MINE_TIMEOUT},
monero,
@ -15,7 +16,7 @@ use crate::{
storage::Database,
SwapAmounts, PUNISH_TIMELOCK, REFUND_TIMELOCK,
};
use anyhow::{anyhow, bail, Context, Result};
use anyhow::{anyhow, Context, Result};
use async_recursion::async_recursion;
use async_trait::async_trait;
use backoff::{backoff::Constant as ConstantBackoff, future::FutureOperation as _};
@ -40,14 +41,15 @@ use xmr_btc::{
alice::{self, action_generator, Action, ReceiveBitcoinRedeemEncsig, State0, State3},
bitcoin::{
poll_until_block_height_is_gte, BroadcastSignedTransaction, GetRawTransaction,
TransactionBlockHeight, TxCancel, TxRefund, WatchForRawTransaction,
WatchForTransactionFinality,
TransactionBlockHeight, TxCancel, TxRefund, WaitForTransactionFinality,
WatchForRawTransaction,
},
bob, cross_curve_dleq,
monero::{CreateWalletForOutput, Transfer},
};
mod amounts;
mod execution;
mod message0;
mod message1;
mod message2;
@ -67,13 +69,11 @@ pub enum AliceState {
v_a: monero::PrivateViewKey,
},
Negotiated {
swap_id: Uuid,
channel: ResponseChannel<AliceToBob>,
amounts: SwapAmounts,
state3: State3,
},
BtcLocked {
swap_id: Uuid,
channel: ResponseChannel<AliceToBob>,
amounts: SwapAmounts,
state3: State3,
@ -117,7 +117,6 @@ pub enum AliceState {
pub async fn simple_swap(
state: AliceState,
mut swarm: Swarm,
db: Database,
bitcoin_wallet: Arc<crate::bitcoin::Wallet>,
monero_wallet: Arc<crate::monero::Wallet>,
) -> Result<AliceState> {
@ -128,166 +127,62 @@ pub async fn simple_swap(
s_a,
v_a,
} => {
// Bob dials us
let bob_peer_id = match swarm.next().await {
OutEvent::ConnectionEstablished(bob_peer_id) => bob_peer_id,
other => bail!("Unexpected event received: {:?}", other),
};
// Bob sends us a request
let (btc, channel) = match swarm.next().await {
OutEvent::Request(amounts::OutEvent::Btc { btc, channel }) => (btc, channel),
other => bail!("Unexpected event received: {:?}", other),
};
if btc != amounts.btc {
bail!(
"Bob proposed a different amount; got {}, expected: {}",
btc,
amounts.btc
);
}
swarm.send_amounts(channel, amounts);
let SwapAmounts { btc, xmr } = amounts;
let redeem_address = bitcoin_wallet.as_ref().new_address().await?;
let punish_address = redeem_address.clone();
let state0 = State0::new(
a,
s_a,
v_a,
btc,
xmr,
REFUND_TIMELOCK,
PUNISH_TIMELOCK,
redeem_address,
punish_address,
);
// Bob sends us message0
let message0 = match swarm.next().await {
OutEvent::Message0(msg) => msg,
other => bail!("Unexpected event received: {:?}", other),
};
let state1 = state0.receive(message0)?;
// TODO(Franck) We should use the same channel everytime,
// Can we remove this response channel?
let (state2, channel) = match swarm.next().await {
OutEvent::Message1 { msg, channel } => {
let state2 = state1.receive(msg);
(state2, channel)
}
other => bail!("Unexpected event: {:?}", other),
};
let message1 = state2.next_message();
swarm.send_message1(channel, message1);
let (state3, channel) = match swarm.next().await {
OutEvent::Message2 { msg, channel } => {
let state3 = state2.receive(msg)?;
(state3, channel)
}
other => bail!("Unexpected event: {:?}", other),
};
let swap_id = Uuid::new_v4();
// TODO(Franck): Use the same terminology (negotiated) to describe this state.
db.insert_latest_state(swap_id, state::Alice::Handshaken(state3.clone()).into())
.await?;
info!(
"State transitioned from Started to Negotiated, Bob peer id is {}",
bob_peer_id
);
let (channel, amounts, state3) =
negotiate(amounts, a, s_a, v_a, &mut swarm, bitcoin_wallet.clone()).await?;
simple_swap(
AliceState::Negotiated {
swap_id,
state3,
channel,
amounts,
state3,
},
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
.await
}
AliceState::Negotiated {
swap_id,
state3,
channel,
amounts,
} => {
// TODO(1): Do a future select with watch bitcoin blockchain time
// TODO(2): Implement a proper safe expiry module
timeout(
Duration::from_secs(TX_LOCK_MINE_TIMEOUT),
// TODO(Franck): Need to check amount?
bitcoin_wallet.watch_for_raw_transaction(state3.tx_lock.txid()),
bitcoin_wallet.wait_for_transaction_finality(state3.tx_lock.txid()),
)
.await
.context("Timed out, Bob did not lock Bitcoin in time")?;
db.insert_latest_state(swap_id, state::Alice::BtcLocked(state3.clone()).into())
.await?;
simple_swap(
AliceState::BtcLocked {
swap_id,
channel,
amounts,
state3,
},
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
.await
}
AliceState::BtcLocked {
swap_id,
channel,
amounts,
state3,
} => {
let S_a = monero::PublicKey::from_private_key(&monero::PrivateKey {
scalar: state3.s_a.into_ed25519(),
});
let public_spend_key = S_a + state3.S_b_monero;
let public_view_key = state3.v.public();
// TODO(Franck): Probably need to wait at least 1 confirmation to be sure that
// we don't wrongfully think this is done.
let (transfer_proof, _) = monero_wallet
.transfer(public_spend_key, public_view_key, amounts.xmr)
.await?;
swarm.send_message2(channel, alice::Message2 {
tx_lock_proof: transfer_proof,
});
// TODO(Franck): we should merge state::Alice and AliceState.
// There should be only 2 states:
// 1. the cryptographic state (State0, etc) which only aware of the crypto
// primitive to execute the protocol 2. the more general/business
// state that contains the crypto + other business data such as network
// communication, amounts to verify, swap id, etc.
db.insert_latest_state(swap_id, state::Alice::XmrLocked(state3.clone()).into())
.await?;
lock_xmr(
channel,
amounts,
state3.clone(),
&mut swarm,
monero_wallet.clone(),
)
.await?;
simple_swap(
AliceState::XmrLocked { state3 },
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
@ -295,8 +190,7 @@ pub async fn simple_swap(
}
AliceState::XmrLocked { state3 } => {
let encsig = timeout(
// TODO(Franck): This is now inefficient as time has been spent since btc was
// locked
// Give a set arbitrary time to Bob to send us `tx_redeem_encsign`
Duration::from_secs(TX_LOCK_MINE_TIMEOUT),
async {
match swarm.next().await {
@ -318,7 +212,6 @@ pub async fn simple_swap(
simple_swap(
AliceState::WaitingToCancel { state3 },
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
@ -330,7 +223,6 @@ pub async fn simple_swap(
simple_swap(
AliceState::WaitingToCancel { state3 },
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
@ -345,7 +237,6 @@ pub async fn simple_swap(
encrypted_signature,
},
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
@ -397,7 +288,6 @@ pub async fn simple_swap(
simple_swap(
AliceState::BtcRedeemed,
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
@ -441,7 +331,6 @@ pub async fn simple_swap(
simple_swap(
AliceState::BtcCancelled { state3, tx_cancel },
swarm,
db,
bitcoin_wallet,
monero_wallet,
)
@ -468,7 +357,6 @@ pub async fn simple_swap(
simple_swap(
AliceState::BtcPunishable { tx_refund, state3 },
swarm,
db,
bitcoin_wallet.clone(),
monero_wallet,
)
@ -482,7 +370,6 @@ pub async fn simple_swap(
state3,
},
swarm,
db,
bitcoin_wallet.clone(),
monero_wallet,
)
@ -552,7 +439,6 @@ pub async fn simple_swap(
state3,
},
swarm,
db,
bitcoin_wallet.clone(),
monero_wallet,
)
@ -563,7 +449,7 @@ pub async fn simple_swap(
tx_refund,
state3,
} => {
let punish_tx_finalised = bitcoin_wallet.watch_for_transaction_finality(punished_tx_id);
let punish_tx_finalised = bitcoin_wallet.wait_for_transaction_finality(punished_tx_id);
let refund_tx_seen = bitcoin_wallet.watch_for_raw_transaction(tx_refund.txid());
@ -575,7 +461,6 @@ pub async fn simple_swap(
simple_swap(
AliceState::Punished,
swarm,
db,
bitcoin_wallet.clone(),
monero_wallet,
)
@ -589,7 +474,6 @@ pub async fn simple_swap(
state3,
},
swarm,
db,
bitcoin_wallet.clone(),
monero_wallet,
)

119
swap/src/alice/execution.rs Normal file
View File

@ -0,0 +1,119 @@
use crate::{
alice::{amounts, OutEvent, Swarm},
network::request_response::AliceToBob,
SwapAmounts, PUNISH_TIMELOCK, REFUND_TIMELOCK,
};
use anyhow::{bail, Result};
use libp2p::request_response::ResponseChannel;
use std::sync::Arc;
use xmr_btc::{
alice,
alice::{State0, State3},
cross_curve_dleq,
monero::Transfer,
};
// TODO(Franck): Make all methods here idempotent using db
pub async fn negotiate(
amounts: SwapAmounts,
a: crate::bitcoin::SecretKey,
s_a: cross_curve_dleq::Scalar,
v_a: crate::monero::PrivateViewKey,
swarm: &mut Swarm,
bitcoin_wallet: Arc<crate::bitcoin::Wallet>,
) -> Result<(ResponseChannel<AliceToBob>, SwapAmounts, State3)> {
// Bob dials us
match swarm.next().await {
OutEvent::ConnectionEstablished(_bob_peer_id) => {}
other => bail!("Unexpected event received: {:?}", other),
};
// Bob sends us a request
let (btc, channel) = match swarm.next().await {
OutEvent::Request(amounts::OutEvent::Btc { btc, channel }) => (btc, channel),
other => bail!("Unexpected event received: {:?}", other),
};
if btc != amounts.btc {
bail!(
"Bob proposed a different amount; got {}, expected: {}",
btc,
amounts.btc
);
}
swarm.send_amounts(channel, amounts);
let SwapAmounts { btc, xmr } = amounts;
let redeem_address = bitcoin_wallet.as_ref().new_address().await?;
let punish_address = redeem_address.clone();
let state0 = State0::new(
a,
s_a,
v_a,
btc,
xmr,
REFUND_TIMELOCK,
PUNISH_TIMELOCK,
redeem_address,
punish_address,
);
// Bob sends us message0
let message0 = match swarm.next().await {
OutEvent::Message0(msg) => msg,
other => bail!("Unexpected event received: {:?}", other),
};
let state1 = state0.receive(message0)?;
let (state2, channel) = match swarm.next().await {
OutEvent::Message1 { msg, channel } => {
let state2 = state1.receive(msg);
(state2, channel)
}
other => bail!("Unexpected event: {:?}", other),
};
let message1 = state2.next_message();
swarm.send_message1(channel, message1);
let (state3, channel) = match swarm.next().await {
OutEvent::Message2 { msg, channel } => {
let state3 = state2.receive(msg)?;
(state3, channel)
}
other => bail!("Unexpected event: {:?}", other),
};
Ok((channel, amounts, state3))
}
pub async fn lock_xmr(
channel: ResponseChannel<AliceToBob>,
amounts: SwapAmounts,
state3: State3,
swarm: &mut Swarm,
monero_wallet: Arc<crate::monero::Wallet>,
) -> Result<()> {
let S_a = monero::PublicKey::from_private_key(&monero::PrivateKey {
scalar: state3.s_a.into_ed25519(),
});
let public_spend_key = S_a + state3.S_b_monero;
let public_view_key = state3.v.public();
let (transfer_proof, _) = monero_wallet
.transfer(public_spend_key, public_view_key, amounts.xmr)
.await?;
swarm.send_message2(channel, alice::Message2 {
tx_lock_proof: transfer_proof,
});
// TODO(Franck): Wait for Monero to be mined/finalised
Ok(())
}

4
swap/src/bitcoin.rs
View File

@ -162,8 +162,8 @@ impl GetRawTransaction for Wallet {
}
#[async_trait]
impl WatchForTransactionFinality for Wallet {
async fn watch_for_transaction_finality(&self, _txid: Txid) {
impl WaitForTransactionFinality for Wallet {
async fn wait_for_transaction_finality(&self, _txid: Txid) {
todo!()
}
}

7
xmr-btc/src/bitcoin.rs
View File

@ -186,9 +186,8 @@ pub trait WatchForRawTransaction {
async fn watch_for_raw_transaction(&self, txid: Txid) -> Transaction;
}
#[async_trait]
pub trait GetRawTransaction {
async fn get_raw_transaction(&self, txid: Txid) -> Result<Transaction>;
pub trait WaitForTransactionFinality {
async fn wait_for_transaction_finality(&self, txid: Txid);
}
#[async_trait]
@ -208,7 +207,7 @@ pub trait WaitForBlockHeight {
#[async_trait]
pub trait GetRawTransaction {
async fn get_raw_transaction(&self, txid: Txid) -> Option<Transaction>;
async fn get_raw_transaction(&self, txid: Txid) -> Result<Transaction>;
}
pub fn recover(S: PublicKey, sig: Signature, encsig: EncryptedSignature) -> Result<SecretKey> {