Actual no_std support

[rust-lightning] / lightning / src / chain / package.rs

// This file is Copyright its original authors, visible in version control
// history.
//
// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
// or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
// You may not use this file except in accordance with one or both of these
// licenses.

//! Various utilities to assemble claimable outpoints in package of one or more transactions. Those
//! packages are attached metadata, guiding their aggregable or fee-bumping re-schedule. This file
//! also includes witness weight computation and fee computation methods.

use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
use bitcoin::blockdata::transaction::{TxOut,TxIn, Transaction, SigHashType};
use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
use bitcoin::blockdata::script::Script;

use bitcoin::hash_types::Txid;

use bitcoin::secp256k1::key::{SecretKey,PublicKey};

use ln::PaymentPreimage;
use ln::chan_utils::{TxCreationKeys, HTLCOutputInCommitment};
use ln::chan_utils;
use ln::msgs::DecodeError;
use chain::chaininterface::{FeeEstimator, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
use chain::keysinterface::Sign;
use chain::onchaintx::OnchainTxHandler;
use util::byte_utils;
use util::logger::Logger;
use util::ser::{Readable, Writer, Writeable};

use io;
use prelude::*;
use core::cmp;
use core::mem;
use core::ops::Deref;

const MAX_ALLOC_SIZE: usize = 64*1024;


// number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
pub(crate) const WEIGHT_REVOKED_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 + 133;
// number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
pub(crate) const WEIGHT_REVOKED_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 33 + 1 +  139;
// number_of_witness_elements + sig_length + counterpartyhtlc_sig  + preimage_length + preimage + witness_script_length + witness_script
pub(crate) const WEIGHT_OFFERED_HTLC: u64 = 1 + 1 + 73 + 1 + 32 + 1 + 133;
// number_of_witness_elements + sig_length + revocation_sig + pubkey_length + revocationpubkey + witness_script_length + witness_script
pub(crate) const WEIGHT_RECEIVED_HTLC: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 139;
// number_of_witness_elements + sig_length + revocation_sig + true_length + op_true + witness_script_length + witness_script
pub(crate) const WEIGHT_REVOKED_OUTPUT: u64 = 1 + 1 + 73 + 1 + 1 + 1 + 77;

/// Height delay at which transactions are fee-bumped/rebroadcasted with a low priority.
const LOW_FREQUENCY_BUMP_INTERVAL: u32 = 15;
/// Height delay at which transactions are fee-bumped/rebroadcasted with a middle priority.
const MIDDLE_FREQUENCY_BUMP_INTERVAL: u32 = 3;
/// Height delay at which transactions are fee-bumped/rebroadcasted with a high priority.
const HIGH_FREQUENCY_BUMP_INTERVAL: u32 = 1;

/// A struct to describe a revoked output and corresponding information to generate a solving
/// witness spending a commitment `to_local` output or a second-stage HTLC transaction output.
///
/// CSV and pubkeys are used as part of a witnessScript redeeming a balance output, amount is used
/// as part of the signature hash and revocation secret to generate a satisfying witness.
#[derive(Clone, PartialEq)]
pub(crate) struct RevokedOutput {
        per_commitment_point: PublicKey,
        counterparty_delayed_payment_base_key: PublicKey,
        counterparty_htlc_base_key: PublicKey,
        per_commitment_key: SecretKey,
        weight: u64,
        amount: u64,
        on_counterparty_tx_csv: u16,
}

impl RevokedOutput {
        pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, per_commitment_key: SecretKey, amount: u64, on_counterparty_tx_csv: u16) -> Self {
                RevokedOutput {
                        per_commitment_point,
                        counterparty_delayed_payment_base_key,
                        counterparty_htlc_base_key,
                        per_commitment_key,
                        weight: WEIGHT_REVOKED_OUTPUT,
                        amount,
                        on_counterparty_tx_csv
                }
        }
}

impl_writeable_tlv_based!(RevokedOutput, {
        (0, per_commitment_point, required),
        (2, counterparty_delayed_payment_base_key, required),
        (4, counterparty_htlc_base_key, required),
        (6, per_commitment_key, required),
        (8, weight, required),
        (10, amount, required),
        (12, on_counterparty_tx_csv, required),
});

/// A struct to describe a revoked offered output and corresponding information to generate a
/// solving witness.
///
/// HTLCOuputInCommitment (hash timelock, direction) and pubkeys are used to generate a suitable
/// witnessScript.
///
/// CSV is used as part of a witnessScript redeeming a balance output, amount is used as part
/// of the signature hash and revocation secret to generate a satisfying witness.
#[derive(Clone, PartialEq)]
pub(crate) struct RevokedHTLCOutput {
        per_commitment_point: PublicKey,
        counterparty_delayed_payment_base_key: PublicKey,
        counterparty_htlc_base_key: PublicKey,
        per_commitment_key: SecretKey,
        weight: u64,
        amount: u64,
        htlc: HTLCOutputInCommitment,
}

impl RevokedHTLCOutput {
        pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, per_commitment_key: SecretKey, amount: u64, htlc: HTLCOutputInCommitment) -> Self {
                let weight = if htlc.offered { WEIGHT_REVOKED_OFFERED_HTLC } else { WEIGHT_REVOKED_RECEIVED_HTLC };
                RevokedHTLCOutput {
                        per_commitment_point,
                        counterparty_delayed_payment_base_key,
                        counterparty_htlc_base_key,
                        per_commitment_key,
                        weight,
                        amount,
                        htlc
                }
        }
}

impl_writeable_tlv_based!(RevokedHTLCOutput, {
        (0, per_commitment_point, required),
        (2, counterparty_delayed_payment_base_key, required),
        (4, counterparty_htlc_base_key, required),
        (6, per_commitment_key, required),
        (8, weight, required),
        (10, amount, required),
        (12, htlc, required),
});

/// A struct to describe a HTLC output on a counterparty commitment transaction.
///
/// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
/// witnessScript.
///
/// The preimage is used as part of the witness.
#[derive(Clone, PartialEq)]
pub(crate) struct CounterpartyOfferedHTLCOutput {
        per_commitment_point: PublicKey,
        counterparty_delayed_payment_base_key: PublicKey,
        counterparty_htlc_base_key: PublicKey,
        preimage: PaymentPreimage,
        htlc: HTLCOutputInCommitment
}

impl CounterpartyOfferedHTLCOutput {
        pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, preimage: PaymentPreimage, htlc: HTLCOutputInCommitment) -> Self {
                CounterpartyOfferedHTLCOutput {
                        per_commitment_point,
                        counterparty_delayed_payment_base_key,
                        counterparty_htlc_base_key,
                        preimage,
                        htlc
                }
        }
}

impl_writeable_tlv_based!(CounterpartyOfferedHTLCOutput, {
        (0, per_commitment_point, required),
        (2, counterparty_delayed_payment_base_key, required),
        (4, counterparty_htlc_base_key, required),
        (6, preimage, required),
        (8, htlc, required),
});

/// A struct to describe a HTLC output on a counterparty commitment transaction.
///
/// HTLCOutputInCommitment (hash, timelock, directon) and pubkeys are used to generate a suitable
/// witnessScript.
#[derive(Clone, PartialEq)]
pub(crate) struct CounterpartyReceivedHTLCOutput {
        per_commitment_point: PublicKey,
        counterparty_delayed_payment_base_key: PublicKey,
        counterparty_htlc_base_key: PublicKey,
        htlc: HTLCOutputInCommitment
}

impl CounterpartyReceivedHTLCOutput {
        pub(crate) fn build(per_commitment_point: PublicKey, counterparty_delayed_payment_base_key: PublicKey, counterparty_htlc_base_key: PublicKey, htlc: HTLCOutputInCommitment) -> Self {
                CounterpartyReceivedHTLCOutput {
                        per_commitment_point,
                        counterparty_delayed_payment_base_key,
                        counterparty_htlc_base_key,
                        htlc
                }
        }
}

impl_writeable_tlv_based!(CounterpartyReceivedHTLCOutput, {
        (0, per_commitment_point, required),
        (2, counterparty_delayed_payment_base_key, required),
        (4, counterparty_htlc_base_key, required),
        (6, htlc, required),
});

/// A struct to describe a HTLC output on holder commitment transaction.
///
/// Either offered or received, the amount is always used as part of the bip143 sighash.
/// Preimage is only included as part of the witness in former case.
#[derive(Clone, PartialEq)]
pub(crate) struct HolderHTLCOutput {
        preimage: Option<PaymentPreimage>,
        amount: u64,
        /// Defaults to 0 for HTLC-Success transactions, which have no expiry
        cltv_expiry: u32,
}

impl HolderHTLCOutput {
        pub(crate) fn build_offered(amount: u64, cltv_expiry: u32) -> Self {
                HolderHTLCOutput {
                        preimage: None,
                        amount,
                        cltv_expiry,
                }
        }

        pub(crate) fn build_accepted(preimage: PaymentPreimage, amount: u64) -> Self {
                HolderHTLCOutput {
                        preimage: Some(preimage),
                        amount,
                        cltv_expiry: 0,
                }
        }
}

impl_writeable_tlv_based!(HolderHTLCOutput, {
        (0, amount, required),
        (2, cltv_expiry, required),
        (4, preimage, option)
});

/// A struct to describe the channel output on the funding transaction.
///
/// witnessScript is used as part of the witness redeeming the funding utxo.
#[derive(Clone, PartialEq)]
pub(crate) struct HolderFundingOutput {
        funding_redeemscript: Script,
}

impl HolderFundingOutput {
        pub(crate) fn build(funding_redeemscript: Script) -> Self {
                HolderFundingOutput {
                        funding_redeemscript,
                }
        }
}

impl_writeable_tlv_based!(HolderFundingOutput, {
        (0, funding_redeemscript, required),
});

/// A wrapper encapsulating all in-protocol differing outputs types.
///
/// The generic API offers access to an outputs common attributes or allow transformation such as
/// finalizing an input claiming the output.
#[derive(Clone, PartialEq)]
pub(crate) enum PackageSolvingData {
        RevokedOutput(RevokedOutput),
        RevokedHTLCOutput(RevokedHTLCOutput),
        CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput),
        CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput),
        HolderHTLCOutput(HolderHTLCOutput),
        HolderFundingOutput(HolderFundingOutput),
}

impl PackageSolvingData {
        fn amount(&self) -> u64 {
                let amt = match self {
                        PackageSolvingData::RevokedOutput(ref outp) => { outp.amount },
                        PackageSolvingData::RevokedHTLCOutput(ref outp) => { outp.amount },
                        PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => { outp.htlc.amount_msat / 1000 },
                        PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => { outp.htlc.amount_msat / 1000 },
                        // Note: Currently, amounts of holder outputs spending witnesses aren't used
                        // as we can't malleate spending package to increase their feerate. This
                        // should change with the remaining anchor output patchset.
                        PackageSolvingData::HolderHTLCOutput(..) => { unreachable!() },
                        PackageSolvingData::HolderFundingOutput(..) => { unreachable!() },
                };
                amt
        }
        fn weight(&self) -> usize {
                let weight = match self {
                        PackageSolvingData::RevokedOutput(ref outp) => { outp.weight as usize },
                        PackageSolvingData::RevokedHTLCOutput(ref outp) => { outp.weight as usize },
                        PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { WEIGHT_OFFERED_HTLC as usize },
                        PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { WEIGHT_RECEIVED_HTLC as usize },
                        // Note: Currently, weights of holder outputs spending witnesses aren't used
                        // as we can't malleate spending package to increase their feerate. This
                        // should change with the remaining anchor output patchset.
                        PackageSolvingData::HolderHTLCOutput(..) => { unreachable!() },
                        PackageSolvingData::HolderFundingOutput(..) => { unreachable!() },
                };
                weight
        }
        fn is_compatible(&self, input: &PackageSolvingData) -> bool {
                match self {
                        PackageSolvingData::RevokedOutput(..) => {
                                match input {
                                        PackageSolvingData::RevokedHTLCOutput(..) => { true },
                                        PackageSolvingData::RevokedOutput(..) => { true },
                                        _ => { false }
                                }
                        },
                        PackageSolvingData::RevokedHTLCOutput(..) => {
                                match input {
                                        PackageSolvingData::RevokedOutput(..) => { true },
                                        PackageSolvingData::RevokedHTLCOutput(..) => { true },
                                        _ => { false }
                                }
                        },
                        _ => { mem::discriminant(self) == mem::discriminant(&input) }
                }
        }
        fn finalize_input<Signer: Sign>(&self, bumped_tx: &mut Transaction, i: usize, onchain_handler: &mut OnchainTxHandler<Signer>) -> bool {
                match self {
                        PackageSolvingData::RevokedOutput(ref outp) => {
                                if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
                                        let witness_script = chan_utils::get_revokeable_redeemscript(&chan_keys.revocation_key, outp.on_counterparty_tx_csv, &chan_keys.broadcaster_delayed_payment_key);
                                        //TODO: should we panic on signer failure ?
                                        if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_output(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &onchain_handler.secp_ctx) {
                                                bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
                                                bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
                                                bumped_tx.input[i].witness.push(vec!(1));
                                                bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
                                        } else { return false; }
                                }
                        },
                        PackageSolvingData::RevokedHTLCOutput(ref outp) => {
                                if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
                                        let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);
                                        //TODO: should we panic on signer failure ?
                                        if let Ok(sig) = onchain_handler.signer.sign_justice_revoked_htlc(&bumped_tx, i, outp.amount, &outp.per_commitment_key, &outp.htlc, &onchain_handler.secp_ctx) {
                                                bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
                                                bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
                                                bumped_tx.input[i].witness.push(chan_keys.revocation_key.clone().serialize().to_vec());
                                                bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
                                        } else { return false; }
                                }
                        },
                        PackageSolvingData::CounterpartyOfferedHTLCOutput(ref outp) => {
                                if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
                                        let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);

                                        if let Ok(sig) = onchain_handler.signer.sign_counterparty_htlc_transaction(&bumped_tx, i, &outp.htlc.amount_msat / 1000, &outp.per_commitment_point, &outp.htlc, &onchain_handler.secp_ctx) {
                                                bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
                                                bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
                                                bumped_tx.input[i].witness.push(outp.preimage.0.to_vec());
                                                bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
                                        }
                                }
                        },
                        PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => {
                                if let Ok(chan_keys) = TxCreationKeys::derive_new(&onchain_handler.secp_ctx, &outp.per_commitment_point, &outp.counterparty_delayed_payment_base_key, &outp.counterparty_htlc_base_key, &onchain_handler.signer.pubkeys().revocation_basepoint, &onchain_handler.signer.pubkeys().htlc_basepoint) {
                                        let witness_script = chan_utils::get_htlc_redeemscript_with_explicit_keys(&outp.htlc, &chan_keys.broadcaster_htlc_key, &chan_keys.countersignatory_htlc_key, &chan_keys.revocation_key);

                                        bumped_tx.lock_time = outp.htlc.cltv_expiry; // Right now we don't aggregate time-locked transaction, if we do we should set lock_time before to avoid breaking hash computation
                                        if let Ok(sig) = onchain_handler.signer.sign_counterparty_htlc_transaction(&bumped_tx, i, &outp.htlc.amount_msat / 1000, &outp.per_commitment_point, &outp.htlc, &onchain_handler.secp_ctx) {
                                                bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
                                                bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
                                                // Due to BIP146 (MINIMALIF) this must be a zero-length element to relay.
                                                bumped_tx.input[i].witness.push(vec![]);
                                                bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
                                        }
                                }
                        },
                        _ => { panic!("API Error!"); }
                }
                true
        }
        fn get_finalized_tx<Signer: Sign>(&self, outpoint: &BitcoinOutPoint, onchain_handler: &mut OnchainTxHandler<Signer>) -> Option<Transaction> {
                match self {
                        PackageSolvingData::HolderHTLCOutput(ref outp) => { return onchain_handler.get_fully_signed_htlc_tx(outpoint, &outp.preimage); }
                        PackageSolvingData::HolderFundingOutput(ref outp) => { return Some(onchain_handler.get_fully_signed_holder_tx(&outp.funding_redeemscript)); }
                        _ => { panic!("API Error!"); }
                }
        }
        fn absolute_tx_timelock(&self, output_conf_height: u32) -> u32 {
                // Get the absolute timelock at which this output can be spent given the height at which
                // this output was confirmed. We use `output_conf_height + 1` as a safe default as we can
                // be confirmed in the next block and transactions with time lock `current_height + 1`
                // always propagate.
                let absolute_timelock = match self {
                        PackageSolvingData::RevokedOutput(_) => output_conf_height + 1,
                        PackageSolvingData::RevokedHTLCOutput(_) => output_conf_height + 1,
                        PackageSolvingData::CounterpartyOfferedHTLCOutput(_) => output_conf_height + 1,
                        PackageSolvingData::CounterpartyReceivedHTLCOutput(ref outp) => cmp::max(outp.htlc.cltv_expiry, output_conf_height + 1),
                        PackageSolvingData::HolderHTLCOutput(ref outp) => cmp::max(outp.cltv_expiry, output_conf_height + 1),
                        PackageSolvingData::HolderFundingOutput(_) => output_conf_height + 1,
                };
                absolute_timelock
        }
}

impl_writeable_tlv_based_enum!(PackageSolvingData, ;
        (0, RevokedOutput),
        (1, RevokedHTLCOutput),
        (2, CounterpartyOfferedHTLCOutput),
        (3, CounterpartyReceivedHTLCOutput),
        (4, HolderHTLCOutput),
        (5, HolderFundingOutput),
);

/// A malleable package might be aggregated with other packages to save on fees.
/// A untractable package has been counter-signed and aggregable will break cached counterparty
/// signatures.
#[derive(Clone, PartialEq)]
pub(crate) enum PackageMalleability {
        Malleable,
        Untractable,
}

/// A structure to describe a package content that is generated by ChannelMonitor and
/// used by OnchainTxHandler to generate and broadcast transactions settling onchain claims.
///
/// A package is defined as one or more transactions claiming onchain outputs in reaction
/// to confirmation of a channel transaction. Those packages might be aggregated to save on
/// fees, if satisfaction of outputs's witnessScript let's us do so.
///
/// As packages are time-sensitive, we fee-bump and rebroadcast them at scheduled intervals.
/// Failing to confirm a package translate as a loss of funds for the user.
#[derive(Clone, PartialEq)]
pub struct PackageTemplate {
        // List of onchain outputs and solving data to generate satisfying witnesses.
        inputs: Vec<(BitcoinOutPoint, PackageSolvingData)>,
        // Packages are deemed as malleable if we have local knwoledge of at least one set of
        // private keys yielding a satisfying witnesses. Malleability implies that we can aggregate
        // packages among them to save on fees or rely on RBF to bump their feerates.
        // Untractable packages have been counter-signed and thus imply that we can't aggregate
        // them without breaking signatures. Fee-bumping strategy will also rely on CPFP.
        malleability: PackageMalleability,
        // Block height after which the earlier-output belonging to this package is mature for a
        // competing claim by the counterparty. As our chain tip becomes nearer from the timelock,
        // the fee-bumping frequency will increase. See `OnchainTxHandler::get_height_timer`.
        soonest_conf_deadline: u32,
        // Determines if this package can be aggregated.
        // Timelocked outputs belonging to the same transaction might have differing
        // satisfying heights. Picking up the later height among the output set would be a valid
        // aggregable strategy but it comes with at least 2 trade-offs :
        // * earlier-output fund are going to take longer to come back
        // * CLTV delta backing up a corresponding HTLC on an upstream channel could be swallowed
        // by the requirement of the later-output part of the set
        // For now, we mark such timelocked outputs as non-aggregable, though we might introduce
        // smarter aggregable strategy in the future.
        aggregable: bool,
        // Cache of package feerate committed at previous (re)broadcast. If bumping resources
        // (either claimed output value or external utxo), it will keep increasing until holder
        // or counterparty successful claim.
        feerate_previous: u64,
        // Cache of next height at which fee-bumping and rebroadcast will be attempted. In
        // the future, we might abstract it to an observed mempool fluctuation.
        height_timer: Option<u32>,
        // Confirmation height of the claimed outputs set transaction. In case of reorg reaching
        // it, we wipe out and forget the package.
        height_original: u32,
}

impl PackageTemplate {
        pub(crate) fn is_malleable(&self) -> bool {
                self.malleability == PackageMalleability::Malleable
        }
        pub(crate) fn timelock(&self) -> u32 {
                self.soonest_conf_deadline
        }
        pub(crate) fn aggregable(&self) -> bool {
                self.aggregable
        }
        pub(crate) fn set_feerate(&mut self, new_feerate: u64) {
                self.feerate_previous = new_feerate;
        }
        pub(crate) fn timer(&self) -> Option<u32> {
                if let Some(ref timer) = self.height_timer {
                        return Some(*timer);
                }
                None
        }
        pub(crate) fn set_timer(&mut self, new_timer: Option<u32>) {
                self.height_timer = new_timer;
        }
        pub(crate) fn outpoints(&self) -> Vec<&BitcoinOutPoint> {
                self.inputs.iter().map(|(o, _)| o).collect()
        }
        pub(crate) fn split_package(&mut self, split_outp: &BitcoinOutPoint) -> Option<PackageTemplate> {
                match self.malleability {
                        PackageMalleability::Malleable => {
                                let mut split_package = None;
                                let timelock = self.soonest_conf_deadline;
                                let aggregable = self.aggregable;
                                let feerate_previous = self.feerate_previous;
                                let height_timer = self.height_timer;
                                let height_original = self.height_original;
                                self.inputs.retain(|outp| {
                                        if *split_outp == outp.0 {
                                                split_package = Some(PackageTemplate {
                                                        inputs: vec![(outp.0, outp.1.clone())],
                                                        malleability: PackageMalleability::Malleable,
                                                        soonest_conf_deadline: timelock,
                                                        aggregable,
                                                        feerate_previous,
                                                        height_timer,
                                                        height_original,
                                                });
                                                return false;
                                        }
                                        return true;
                                });
                                return split_package;
                        },
                        _ => {
                                // Note, we may try to split on remote transaction for
                                // which we don't have a competing one (HTLC-Success before
                                // timelock expiration). This explain we don't panic!
                                // We should refactor OnchainTxHandler::block_connected to
                                // only test equality on competing claims.
                                return None;
                        }
                }
        }
        pub(crate) fn merge_package(&mut self, mut merge_from: PackageTemplate) {
                assert_eq!(self.height_original, merge_from.height_original);
                if self.malleability == PackageMalleability::Untractable || merge_from.malleability == PackageMalleability::Untractable {
                        panic!("Merging template on untractable packages");
                }
                if !self.aggregable || !merge_from.aggregable {
                        panic!("Merging non aggregatable packages");
                }
                if let Some((_, lead_input)) = self.inputs.first() {
                        for (_, v) in merge_from.inputs.iter() {
                                if !lead_input.is_compatible(v) { panic!("Merging outputs from differing types !"); }
                        }
                } else { panic!("Merging template on an empty package"); }
                for (k, v) in merge_from.inputs.drain(..) {
                        self.inputs.push((k, v));
                }
                //TODO: verify coverage and sanity?
                if self.soonest_conf_deadline > merge_from.soonest_conf_deadline {
                        self.soonest_conf_deadline = merge_from.soonest_conf_deadline;
                }
                if self.feerate_previous > merge_from.feerate_previous {
                        self.feerate_previous = merge_from.feerate_previous;
                }
                self.height_timer = cmp::min(self.height_timer, merge_from.height_timer);
        }
        /// Gets the amount of all outptus being spent by this package, only valid for malleable
        /// packages.
        fn package_amount(&self) -> u64 {
                let mut amounts = 0;
                for (_, outp) in self.inputs.iter() {
                        amounts += outp.amount();
                }
                amounts
        }
        pub(crate) fn package_timelock(&self) -> u32 {
                self.inputs.iter().map(|(_, outp)| outp.absolute_tx_timelock(self.height_original))
                        .max().expect("There must always be at least one output to spend in a PackageTemplate")
        }
        pub(crate) fn package_weight(&self, destination_script: &Script) -> usize {
                let mut inputs_weight = 0;
                let mut witnesses_weight = 2; // count segwit flags
                for (_, outp) in self.inputs.iter() {
                        // previous_out_point: 36 bytes ; var_int: 1 byte ; sequence: 4 bytes
                        inputs_weight += 41 * WITNESS_SCALE_FACTOR;
                        witnesses_weight += outp.weight();
                }
                // version: 4 bytes ; count_tx_in: 1 byte ; count_tx_out: 1 byte ; lock_time: 4 bytes
                let transaction_weight = 10 * WITNESS_SCALE_FACTOR;
                // value: 8 bytes ; var_int: 1 byte ; pk_script: `destination_script.len()`
                let output_weight = (8 + 1 + destination_script.len()) * WITNESS_SCALE_FACTOR;
                inputs_weight + witnesses_weight + transaction_weight + output_weight
        }
        pub(crate) fn finalize_package<L: Deref, Signer: Sign>(&self, onchain_handler: &mut OnchainTxHandler<Signer>, value: u64, destination_script: Script, logger: &L) -> Option<Transaction>
                where L::Target: Logger,
        {
                match self.malleability {
                        PackageMalleability::Malleable => {
                                let mut bumped_tx = Transaction {
                                        version: 2,
                                        lock_time: 0,
                                        input: vec![],
                                        output: vec![TxOut {
                                                script_pubkey: destination_script,
                                                value,
                                        }],
                                };
                                for (outpoint, _) in self.inputs.iter() {
                                        bumped_tx.input.push(TxIn {
                                                previous_output: *outpoint,
                                                script_sig: Script::new(),
                                                sequence: 0xfffffffd,
                                                witness: Vec::new(),
                                        });
                                }
                                for (i, (outpoint, out)) in self.inputs.iter().enumerate() {
                                        log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
                                        if !out.finalize_input(&mut bumped_tx, i, onchain_handler) { return None; }
                                }
                                log_debug!(logger, "Finalized transaction {} ready to broadcast", bumped_tx.txid());
                                return Some(bumped_tx);
                        },
                        PackageMalleability::Untractable => {
                                debug_assert_eq!(value, 0, "value is ignored for non-malleable packages, should be zero to ensure callsites are correct");
                                if let Some((outpoint, outp)) = self.inputs.first() {
                                        if let Some(final_tx) = outp.get_finalized_tx(outpoint, onchain_handler) {
                                                log_debug!(logger, "Adding claiming input for outpoint {}:{}", outpoint.txid, outpoint.vout);
                                                log_debug!(logger, "Finalized transaction {} ready to broadcast", final_tx.txid());
                                                return Some(final_tx);
                                        }
                                        return None;
                                } else { panic!("API Error: Package must not be inputs empty"); }
                        },
                }
        }
        /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
        /// output detection, we generate a first version of a claim tx and associate to it a height timer. A height timer is an absolute block
        /// height that once reached we should generate a new bumped "version" of the claim tx to be sure that we safely claim outputs before
        /// that our counterparty can do so. If timelock expires soon, height timer is going to be scaled down in consequence to increase
        /// frequency of the bump and so increase our bets of success.
        pub(crate) fn get_height_timer(&self, current_height: u32) -> u32 {
                if self.soonest_conf_deadline <= current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL {
                        return current_height + HIGH_FREQUENCY_BUMP_INTERVAL
                } else if self.soonest_conf_deadline - current_height <= LOW_FREQUENCY_BUMP_INTERVAL {
                        return current_height + MIDDLE_FREQUENCY_BUMP_INTERVAL
                }
                current_height + LOW_FREQUENCY_BUMP_INTERVAL
        }
        /// Returns value in satoshis to be included as package outgoing output amount and feerate with which package finalization should be done.
        pub(crate) fn compute_package_output<F: Deref, L: Deref>(&self, predicted_weight: usize, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
                where F::Target: FeeEstimator,
                      L::Target: Logger,
        {
                debug_assert!(self.malleability == PackageMalleability::Malleable, "The package output is fixed for non-malleable packages");
                let input_amounts = self.package_amount();
                // If old feerate is 0, first iteration of this claim, use normal fee calculation
                if self.feerate_previous != 0 {
                        if let Some((new_fee, feerate)) = feerate_bump(predicted_weight, input_amounts, self.feerate_previous, fee_estimator, logger) {
                                // If new computed fee is superior at the whole claimable amount burn all in fees
                                if new_fee > input_amounts {
                                        return Some((0, feerate));
                                } else {
                                        return Some((input_amounts - new_fee, feerate));
                                }
                        }
                } else {
                        if let Some((new_fee, feerate)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
                                return Some((input_amounts - new_fee, feerate));
                        }
                }
                None
        }
        pub (crate) fn build_package(txid: Txid, vout: u32, input_solving_data: PackageSolvingData, soonest_conf_deadline: u32, aggregable: bool, height_original: u32) -> Self {
                let malleability = match input_solving_data {
                        PackageSolvingData::RevokedOutput(..) => { PackageMalleability::Malleable },
                        PackageSolvingData::RevokedHTLCOutput(..) => { PackageMalleability::Malleable },
                        PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { PackageMalleability::Malleable },
                        PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { PackageMalleability::Malleable },
                        PackageSolvingData::HolderHTLCOutput(..) => { PackageMalleability::Untractable },
                        PackageSolvingData::HolderFundingOutput(..) => { PackageMalleability::Untractable },
                };
                let mut inputs = Vec::with_capacity(1);
                inputs.push((BitcoinOutPoint { txid, vout }, input_solving_data));
                PackageTemplate {
                        inputs,
                        malleability,
                        soonest_conf_deadline,
                        aggregable,
                        feerate_previous: 0,
                        height_timer: None,
                        height_original,
                }
        }
}

impl Writeable for PackageTemplate {
        fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
                writer.write_all(&byte_utils::be64_to_array(self.inputs.len() as u64))?;
                for (ref outpoint, ref rev_outp) in self.inputs.iter() {
                        outpoint.write(writer)?;
                        rev_outp.write(writer)?;
                }
                write_tlv_fields!(writer, {
                        (0, self.soonest_conf_deadline, required),
                        (2, self.feerate_previous, required),
                        (4, self.height_original, required),
                        (6, self.height_timer, option)
                });
                Ok(())
        }
}

impl Readable for PackageTemplate {
        fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
                let inputs_count = <u64 as Readable>::read(reader)?;
                let mut inputs: Vec<(BitcoinOutPoint, PackageSolvingData)> = Vec::with_capacity(cmp::min(inputs_count as usize, MAX_ALLOC_SIZE / 128));
                for _ in 0..inputs_count {
                        let outpoint = Readable::read(reader)?;
                        let rev_outp = Readable::read(reader)?;
                        inputs.push((outpoint, rev_outp));
                }
                let (malleability, aggregable) = if let Some((_, lead_input)) = inputs.first() {
                        match lead_input {
                                PackageSolvingData::RevokedOutput(..) => { (PackageMalleability::Malleable, true) },
                                PackageSolvingData::RevokedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
                                PackageSolvingData::CounterpartyOfferedHTLCOutput(..) => { (PackageMalleability::Malleable, true) },
                                PackageSolvingData::CounterpartyReceivedHTLCOutput(..) => { (PackageMalleability::Malleable, false) },
                                PackageSolvingData::HolderHTLCOutput(..) => { (PackageMalleability::Untractable, false) },
                                PackageSolvingData::HolderFundingOutput(..) => { (PackageMalleability::Untractable, false) },
                        }
                } else { return Err(DecodeError::InvalidValue); };
                let mut soonest_conf_deadline = 0;
                let mut feerate_previous = 0;
                let mut height_timer = None;
                let mut height_original = 0;
                read_tlv_fields!(reader, {
                        (0, soonest_conf_deadline, required),
                        (2, feerate_previous, required),
                        (4, height_original, required),
                        (6, height_timer, option),
                });
                Ok(PackageTemplate {
                        inputs,
                        malleability,
                        soonest_conf_deadline,
                        aggregable,
                        feerate_previous,
                        height_timer,
                        height_original,
                })
        }
}

/// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
/// weight. We start with the highest priority feerate returned by the node's fee estimator then
/// fall-back to lower priorities until we have enough value available to suck from.
///
/// If the proposed fee is less than the available spent output's values, we return the proposed
/// fee and the corresponding updated feerate. If the proposed fee is equal or more than the
/// available spent output's values, we return nothing
fn compute_fee_from_spent_amounts<F: Deref, L: Deref>(input_amounts: u64, predicted_weight: usize, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
        where F::Target: FeeEstimator,
              L::Target: Logger,
{
        let mut updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64;
        let mut fee = updated_feerate * (predicted_weight as u64) / 1000;
        if input_amounts <= fee {
                updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal) as u64;
                fee = updated_feerate * (predicted_weight as u64) / 1000;
                if input_amounts <= fee {
                        updated_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) as u64;
                        fee = updated_feerate * (predicted_weight as u64) / 1000;
                        if input_amounts <= fee {
                                log_error!(logger, "Failed to generate an on-chain punishment tx as even low priority fee ({} sat) was more than the entire claim balance ({} sat)",
                                        fee, input_amounts);
                                None
                        } else {
                                log_warn!(logger, "Used low priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
                                        input_amounts);
                                Some((fee, updated_feerate))
                        }
                } else {
                        log_warn!(logger, "Used medium priority fee for on-chain punishment tx as high priority fee was more than the entire claim balance ({} sat)",
                                input_amounts);
                        Some((fee, updated_feerate))
                }
        } else {
                Some((fee, updated_feerate))
        }
}

/// Attempt to propose a bumping fee for a transaction from its spent output's values and predicted
/// weight. If feerates proposed by the fee-estimator have been increasing since last fee-bumping
/// attempt, use them. Otherwise, blindly bump the feerate by 25% of the previous feerate. We also
/// verify that those bumping heuristics respect BIP125 rules 3) and 4) and if required adjust
/// the new fee to meet the RBF policy requirement.
fn feerate_bump<F: Deref, L: Deref>(predicted_weight: usize, input_amounts: u64, previous_feerate: u64, fee_estimator: &F, logger: &L) -> Option<(u64, u64)>
        where F::Target: FeeEstimator,
              L::Target: Logger,
{
        // If old feerate inferior to actual one given back by Fee Estimator, use it to compute new fee...
        let new_fee = if let Some((new_fee, _)) = compute_fee_from_spent_amounts(input_amounts, predicted_weight, fee_estimator, logger) {
                let updated_feerate = new_fee / (predicted_weight as u64 * 1000);
                if updated_feerate > previous_feerate {
                        new_fee
                } else {
                        // ...else just increase the previous feerate by 25% (because that's a nice number)
                        let new_fee = previous_feerate * (predicted_weight as u64) / 750;
                        if input_amounts <= new_fee {
                                log_warn!(logger, "Can't 25% bump new claiming tx, amount {} is too small", input_amounts);
                                return None;
                        }
                        new_fee
                }
        } else {
                log_warn!(logger, "Can't new-estimation bump new claiming tx, amount {} is too small", input_amounts);
                return None;
        };

        let previous_fee = previous_feerate * (predicted_weight as u64) / 1000;
        let min_relay_fee = MIN_RELAY_FEE_SAT_PER_1000_WEIGHT * (predicted_weight as u64) / 1000;
        // BIP 125 Opt-in Full Replace-by-Fee Signaling
        //      * 3. The replacement transaction pays an absolute fee of at least the sum paid by the original transactions.
        //      * 4. The replacement transaction must also pay for its own bandwidth at or above the rate set by the node's minimum relay fee setting.
        let new_fee = if new_fee < previous_fee + min_relay_fee {
                new_fee + previous_fee + min_relay_fee - new_fee
        } else {
                new_fee
        };
        Some((new_fee, new_fee * 1000 / (predicted_weight as u64)))
}

#[cfg(test)]
mod tests {
        use chain::package::{CounterpartyReceivedHTLCOutput, HolderHTLCOutput, PackageTemplate, PackageSolvingData, RevokedOutput, WEIGHT_REVOKED_OUTPUT};
        use chain::Txid;
        use ln::chan_utils::HTLCOutputInCommitment;
        use ln::{PaymentPreimage, PaymentHash};

        use bitcoin::blockdata::constants::WITNESS_SCALE_FACTOR;
        use bitcoin::blockdata::script::Script;
        use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;

        use bitcoin::hashes::hex::FromHex;

        use bitcoin::secp256k1::key::{PublicKey,SecretKey};
        use bitcoin::secp256k1::Secp256k1;

        macro_rules! dumb_revk_output {
                ($secp_ctx: expr) => {
                        {
                                let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
                                let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
                                PackageSolvingData::RevokedOutput(RevokedOutput::build(dumb_point, dumb_point, dumb_point, dumb_scalar, 0, 0))
                        }
                }
        }

        macro_rules! dumb_counterparty_output {
                ($secp_ctx: expr, $amt: expr) => {
                        {
                                let dumb_scalar = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
                                let dumb_point = PublicKey::from_secret_key(&$secp_ctx, &dumb_scalar);
                                let hash = PaymentHash([1; 32]);
                                let htlc = HTLCOutputInCommitment { offered: true, amount_msat: $amt, cltv_expiry: 0, payment_hash: hash, transaction_output_index: None };
                                PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(dumb_point, dumb_point, dumb_point, htlc))
                        }
                }
        }

        macro_rules! dumb_htlc_output {
                () => {
                        {
                                let preimage = PaymentPreimage([2;32]);
                                PackageSolvingData::HolderHTLCOutput(HolderHTLCOutput::build_accepted(preimage, 0))
                        }
                }
        }

        #[test]
        #[should_panic]
        fn test_package_differing_heights() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let mut package_one_hundred = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
                let package_two_hundred = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 200);
                package_one_hundred.merge_package(package_two_hundred);
        }

        #[test]
        #[should_panic]
        fn test_package_untractable_merge_to() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);
                let htlc_outp = dumb_htlc_output!();

                let mut untractable_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
                let malleable_package = PackageTemplate::build_package(txid, 1, htlc_outp.clone(), 1000, true, 100);
                untractable_package.merge_package(malleable_package);
        }

        #[test]
        #[should_panic]
        fn test_package_untractable_merge_from() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let htlc_outp = dumb_htlc_output!();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let mut malleable_package = PackageTemplate::build_package(txid, 0, htlc_outp.clone(), 1000, true, 100);
                let untractable_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
                malleable_package.merge_package(untractable_package);
        }

        #[test]
        #[should_panic]
        fn test_package_noaggregation_to() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let mut noaggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, false, 100);
                let aggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
                noaggregation_package.merge_package(aggregation_package);
        }

        #[test]
        #[should_panic]
        fn test_package_noaggregation_from() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let mut aggregation_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
                let noaggregation_package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, false, 100);
                aggregation_package.merge_package(noaggregation_package);
        }

        #[test]
        #[should_panic]
        fn test_package_empty() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let mut empty_package = PackageTemplate::build_package(txid, 0, revk_outp.clone(), 1000, true, 100);
                empty_package.inputs = vec![];
                let package = PackageTemplate::build_package(txid, 1, revk_outp.clone(), 1000, true, 100);
                empty_package.merge_package(package);
        }

        #[test]
        #[should_panic]
        fn test_package_differing_categories() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);
                let counterparty_outp = dumb_counterparty_output!(secp_ctx, 0);

                let mut revoked_package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100);
                let counterparty_package = PackageTemplate::build_package(txid, 1, counterparty_outp, 1000, true, 100);
                revoked_package.merge_package(counterparty_package);
        }

        #[test]
        fn test_package_split_malleable() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp_one = dumb_revk_output!(secp_ctx);
                let revk_outp_two = dumb_revk_output!(secp_ctx);
                let revk_outp_three = dumb_revk_output!(secp_ctx);

                let mut package_one = PackageTemplate::build_package(txid, 0, revk_outp_one, 1000, true, 100);
                let package_two = PackageTemplate::build_package(txid, 1, revk_outp_two, 1000, true, 100);
                let package_three = PackageTemplate::build_package(txid, 2, revk_outp_three, 1000, true, 100);

                package_one.merge_package(package_two);
                package_one.merge_package(package_three);
                assert_eq!(package_one.outpoints().len(), 3);

                if let Some(split_package) = package_one.split_package(&BitcoinOutPoint { txid, vout: 1 }) {
                        // Packages attributes should be identical
                        assert!(split_package.is_malleable());
                        assert_eq!(split_package.soonest_conf_deadline, package_one.soonest_conf_deadline);
                        assert_eq!(split_package.aggregable, package_one.aggregable);
                        assert_eq!(split_package.feerate_previous, package_one.feerate_previous);
                        assert_eq!(split_package.height_timer, package_one.height_timer);
                        assert_eq!(split_package.height_original, package_one.height_original);
                } else { panic!(); }
                assert_eq!(package_one.outpoints().len(), 2);
        }

        #[test]
        fn test_package_split_untractable() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let htlc_outp_one = dumb_htlc_output!();

                let mut package_one = PackageTemplate::build_package(txid, 0, htlc_outp_one, 1000, true, 100);
                let ret_split = package_one.split_package(&BitcoinOutPoint { txid, vout: 0});
                assert!(ret_split.is_none());
        }

        #[test]
        fn test_package_timer() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let mut package = PackageTemplate::build_package(txid, 0, revk_outp, 1000, true, 100);
                let timer_none = package.timer();
                assert!(timer_none.is_none());
                package.set_timer(Some(100));
                if let Some(timer_some) = package.timer() {
                        assert_eq!(timer_some, 100);
                } else { panic!() }
        }

        #[test]
        fn test_package_amounts() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let counterparty_outp = dumb_counterparty_output!(secp_ctx, 1_000_000);

                let package = PackageTemplate::build_package(txid, 0, counterparty_outp, 1000, true, 100);
                assert_eq!(package.package_amount(), 1000);
        }

        #[test]
        fn test_package_weight() {
                let txid = Txid::from_hex("c2d4449afa8d26140898dd54d3390b057ba2a5afcf03ba29d7dc0d8b9ffe966e").unwrap();
                let secp_ctx = Secp256k1::new();
                let revk_outp = dumb_revk_output!(secp_ctx);

                let package = PackageTemplate::build_package(txid, 0, revk_outp, 0, true, 100);
                // (nVersion (4) + nLocktime (4) + count_tx_in (1) + prevout (36) + sequence (4) + script_length (1) + count_tx_out (1) + value (8) + var_int (1)) * WITNESS_SCALE_FACTOR
                // + witness marker (2) + WEIGHT_REVOKED_OUTPUT
                assert_eq!(package.package_weight(&Script::new()), (4 + 4 + 1 + 36 + 4 + 1 + 1 + 8 + 1) * WITNESS_SCALE_FACTOR + 2 + WEIGHT_REVOKED_OUTPUT as usize);
        }
}