Added config interface to allow users to specify channel limits

Author: SWvheerden

fuzz/fuzz_targets/full_stack_target.rs

@@ -24,6 +24,7 @@ use lightning::util::events::{EventsProvider,Event};
 use lightning::util::reset_rng_state;
 use lightning::util::logger::Logger;
 use lightning::util::sha2::Sha256;
+use lightning::util::config::UserConfig;
 
 mod utils;
 
@@ -305,7 +306,11 @@ pub fn do_test(data: &[u8], logger: &Arc<Logger>) {
 	let monitor = channelmonitor::SimpleManyChannelMonitor::new(watch.clone(), broadcast.clone(), Arc::clone(&logger));
 
 	let keys_manager = Arc::new(KeyProvider { node_secret: our_network_key.clone() });
-	let channelmanager = ChannelManager::new(slice_to_be32(get_slice!(4)), get_slice!(1)[0] != 0, Network::Bitcoin, fee_est.clone(), monitor.clone(), watch.clone(), broadcast.clone(), Arc::clone(&logger), keys_manager.clone()).unwrap();
+	let mut config = UserConfig::new();
+	config.channel_options.fee_proportional_millionths =  slice_to_be32(get_slice!(4));
+	config.channel_options.announced_channel = get_slice!(1)[0] != 0;
+	config.channel_limits.min_dust_limit_satoshis = 0;
+	let channelmanager = ChannelManager::new(Network::Bitcoin, fee_est.clone(), monitor.clone(), watch.clone(), broadcast.clone(), Arc::clone(&logger), keys_manager.clone(), config).unwrap();
 	let router = Arc::new(Router::new(PublicKey::from_secret_key(&secp_ctx, &keys_manager.get_node_secret()), watch.clone(), Arc::clone(&logger)));
 
 	let peers = RefCell::new([false; 256]);

src/ln/channel.rs

@@ -28,6 +28,7 @@ use util::ser::{Readable, ReadableArgs, Writeable, Writer, WriterWriteAdaptor};
 use util::sha2::Sha256;
 use util::logger::Logger;
 use util::errors::APIError;
+use util::config::{UserConfig,ChannelConfig};
 
 use std;
 use std::default::Default;
@@ -230,13 +231,14 @@ const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
 // calling channel_id() before we're set up or things like get_outbound_funding_signed on an
 // inbound channel.
 pub(super) struct Channel {
+	config: ChannelConfig,
+
 	user_id: u64,
 
 	channel_id: [u8; 32],
 	channel_state: u32,
 	channel_outbound: bool,
 	secp_ctx: Secp256k1<secp256k1::All>,
-	announce_publicly: bool,
 	channel_value_satoshis: u64,
 
 	local_keys: ChannelKeys,
@@ -415,7 +417,7 @@ impl Channel {
 	}
 
 	// Constructors:
-	pub fn new_outbound(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, announce_publicly: bool, user_id: u64, logger: Arc<Logger>) -> Result<Channel, APIError> {
+	pub fn new_outbound(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel, APIError> {
 		let chan_keys = keys_provider.get_channel_keys(false);
 
 		if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
@@ -441,12 +443,12 @@ impl Channel {
 
 		Ok(Channel {
 			user_id: user_id,
+			config: config.channel_options.clone(),
 
 			channel_id: rng::rand_u832(),
 			channel_state: ChannelState::OurInitSent as u32,
 			channel_outbound: true,
 			secp_ctx: secp_ctx,
-			announce_publicly: announce_publicly,
 			channel_value_satoshis: channel_value_satoshis,
 
 			local_keys: chan_keys,
@@ -526,8 +528,9 @@ impl Channel {
 
 	/// Creates a new channel from a remote sides' request for one.
 	/// Assumes chain_hash has already been checked and corresponds with what we expect!
-	pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, msg: &msgs::OpenChannel, user_id: u64, require_announce: bool, allow_announce: bool, logger: Arc<Logger>) -> Result<Channel, ChannelError> {
+	pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface>, their_node_id: PublicKey, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel, ChannelError> {
 		let chan_keys = keys_provider.get_channel_keys(true);
+		let mut local_config = (*config).channel_options.clone();
 
 		// Check sanity of message fields:
 		if msg.funding_satoshis >= MAX_FUNDING_SATOSHIS {
@@ -560,22 +563,46 @@ impl Channel {
 			return Err(ChannelError::Close("max_accpted_htlcs > 483"));
 		}
 
+		// Now check against optional parameters as set by config...
+		if msg.funding_satoshis < config.channel_limits.min_funding_satoshis {
+			return Err(ChannelError::Close("funding satoshis is less than the user specified limit"));
+		}
+		if msg.htlc_minimum_msat > config.channel_limits.max_htlc_minimum_msat {
+			return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit"));
+		}
+		if msg.max_htlc_value_in_flight_msat < config.channel_limits.min_max_htlc_value_in_flight_msat {
+			return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit"));
+		}
+		if msg.channel_reserve_satoshis > config.channel_limits.max_channel_reserve_satoshis {
+			return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit"));
+		}
+		if msg.max_accepted_htlcs < config.channel_limits.min_max_accepted_htlcs {
+			return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit"));
+		}
+		if msg.dust_limit_satoshis < config.channel_limits.min_dust_limit_satoshis {
+			return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit"));
+		}
+		if msg.dust_limit_satoshis > config.channel_limits.max_dust_limit_satoshis {
+			return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit"));
+		}
+
 		// Convert things into internal flags and prep our state:
 
 		let their_announce = if (msg.channel_flags & 1) == 1 { true } else { false };
-		if require_announce && !their_announce {
-			return Err(ChannelError::Close("Peer tried to open unannounced channel, but we require public ones"));
-		}
-		if !allow_announce && their_announce {
-			return Err(ChannelError::Close("Peer tried to open announced channel, but we require private ones"));
+		if config.channel_limits.force_announced_channel_preference {
+			if local_config.announced_channel != their_announce {
+				return Err(ChannelError::Close("Peer tried to open channel but their announcement preference is different from ours"));
+			}
 		}
+		// we either accept their preference or the preferences match
+		local_config.announced_channel = their_announce;
 
 		let background_feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background);
 
 		let our_dust_limit_satoshis = Channel::derive_our_dust_limit_satoshis(background_feerate);
 		let our_channel_reserve_satoshis = Channel::get_our_channel_reserve_satoshis(msg.funding_satoshis);
 		if our_channel_reserve_satoshis < our_dust_limit_satoshis {
-			return Err(ChannelError::Close("Suitalbe channel reserve not found. aborting"));
+			return Err(ChannelError::Close("Suitable channel reserve not found. aborting"));
 		}
 		if msg.channel_reserve_satoshis < our_dust_limit_satoshis {
 			return Err(ChannelError::Close("channel_reserve_satoshis too small"));
@@ -606,12 +633,12 @@ impl Channel {
 
 		let mut chan = Channel {
 			user_id: user_id,
+			config: local_config,
 
 			channel_id: msg.temporary_channel_id,
 			channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
 			channel_outbound: false,
 			secp_ctx: secp_ctx,
-			announce_publicly: their_announce,
 
 			local_keys: chan_keys,
 			shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
@@ -1262,7 +1289,7 @@ impl Channel {
 
 	// Message handlers:
 
-	pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel) -> Result<(), ChannelError> {
+	pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig) -> Result<(), ChannelError> {
 		// Check sanity of message fields:
 		if !self.channel_outbound {
 			return Err(ChannelError::Close("Got an accept_channel message from an inbound peer"));
@@ -1298,14 +1325,28 @@ impl Channel {
 			return Err(ChannelError::Close("max_accpted_htlcs > 483"));
 		}
 
-		// TODO: Optional additional constraints mentioned in the spec
-		// MAY fail the channel if
-		// funding_satoshi is too small
-		// htlc_minimum_msat too large
-		// max_htlc_value_in_flight_msat too small
-		// channel_reserve_satoshis too large
-		// max_accepted_htlcs too small
-		// dust_limit_satoshis too small
+		// Now check against optional parameters as set by config...
+		if msg.htlc_minimum_msat > config.channel_limits.max_htlc_minimum_msat {
+			return Err(ChannelError::Close("htlc minimum msat is higher than the user specified limit"));
+		}
+		if msg.max_htlc_value_in_flight_msat < config.channel_limits.min_max_htlc_value_in_flight_msat {
+			return Err(ChannelError::Close("max htlc value in flight msat is less than the user specified limit"));
+		}
+		if msg.channel_reserve_satoshis > config.channel_limits.max_channel_reserve_satoshis {
+			return Err(ChannelError::Close("channel reserve satoshis is higher than the user specified limit"));
+		}
+		if msg.max_accepted_htlcs < config.channel_limits.min_max_accepted_htlcs {
+			return Err(ChannelError::Close("max accepted htlcs is less than the user specified limit"));
+		}
+		if msg.dust_limit_satoshis < config.channel_limits.min_dust_limit_satoshis {
+			return Err(ChannelError::Close("dust limit satoshis is less than the user specified limit"));
+		}
+		if msg.dust_limit_satoshis > config.channel_limits.max_dust_limit_satoshis {
+			return Err(ChannelError::Close("dust limit satoshis is greater than the user specified limit"));
+		}
+		if msg.minimum_depth > config.channel_limits.max_minimum_depth {
+			return Err(ChannelError::Close("We consider the minimum depth to be unreasonably large"));
+		}
 
 		self.channel_monitor.set_their_base_keys(&msg.htlc_basepoint, &msg.delayed_payment_basepoint);
 
@@ -2571,6 +2612,10 @@ impl Channel {
 		self.channel_value_satoshis
 	}
 
+	pub fn get_fee_proportional_millionths(&self) -> u32 {
+		self.config.fee_proportional_millionths
+	}
+
 	#[cfg(test)]
 	pub fn get_feerate(&self) -> u64 {
 		self.feerate_per_kw
@@ -2624,7 +2669,7 @@ impl Channel {
 	}
 
 	pub fn should_announce(&self) -> bool {
-		self.announce_publicly
+		self.config.announced_channel
 	}
 
 	pub fn is_outbound(&self) -> bool {
@@ -2823,7 +2868,7 @@ impl Channel {
 			delayed_payment_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.delayed_payment_base_key),
 			htlc_basepoint: PublicKey::from_secret_key(&self.secp_ctx, &self.local_keys.htlc_base_key),
 			first_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &local_commitment_secret),
-			channel_flags: if self.announce_publicly {1} else {0},
+			channel_flags: if self.config.announced_channel {1} else {0},
 			shutdown_scriptpubkey: None,
 		}
 	}
@@ -2927,7 +2972,7 @@ impl Channel {
 	/// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
 	/// https://github.com/lightningnetwork/lightning-rfc/issues/468
 	pub fn get_channel_announcement(&self, our_node_id: PublicKey, chain_hash: Sha256dHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
-		if !self.announce_publicly {
+		if !self.config.announced_channel {
 			return Err(ChannelError::Ignore("Channel is not available for public announcements"));
 		}
 		if self.channel_state & (ChannelState::ChannelFunded as u32) == 0 {
@@ -3303,11 +3348,11 @@ impl Writeable for Channel {
 		writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
 
 		self.user_id.write(writer)?;
+		self.config.write(writer)?;
 
 		self.channel_id.write(writer)?;
 		(self.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
 		self.channel_outbound.write(writer)?;
-		self.announce_publicly.write(writer)?;
 		self.channel_value_satoshis.write(writer)?;
 
 		self.local_keys.write(writer)?;
@@ -3506,11 +3551,11 @@ impl<R : ::std::io::Read> ReadableArgs<R, Arc<Logger>> for Channel {
 		}
 
 		let user_id = Readable::read(reader)?;
+		let config: ChannelConfig = Readable::read(reader)?;
 
 		let channel_id = Readable::read(reader)?;
 		let channel_state = Readable::read(reader)?;
 		let channel_outbound = Readable::read(reader)?;
-		let announce_publicly = Readable::read(reader)?;
 		let channel_value_satoshis = Readable::read(reader)?;
 
 		let local_keys = Readable::read(reader)?;
@@ -3675,11 +3720,11 @@ impl<R : ::std::io::Read> ReadableArgs<R, Arc<Logger>> for Channel {
 		Ok(Channel {
 			user_id,
 
+			config,
 			channel_id,
 			channel_state,
 			channel_outbound,
 			secp_ctx: Secp256k1::new(),
-			announce_publicly,
 			channel_value_satoshis,
 
 			local_keys,
@@ -3766,6 +3811,7 @@ mod tests {
 	use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
 	use chain::keysinterface::KeysInterface;
 	use chain::transaction::OutPoint;
+	use util::config::UserConfig;
 	use util::test_utils;
 	use util::logger::Logger;
 	use secp256k1::{Secp256k1,Message,Signature};
@@ -3832,7 +3878,9 @@ mod tests {
 		let keys_provider: Arc<KeysInterface> = Arc::new(Keys { chan_keys });
 
 		let their_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&secp_ctx, &[42; 32]).unwrap());
-		let mut chan = Channel::new_outbound(&feeest, &keys_provider, their_node_id, 10000000, 100000, false, 42, Arc::clone(&logger)).unwrap(); // Nothing uses their network key in this test
+		let mut config = UserConfig::new();
+		config.channel_options.announced_channel = false;
+		let mut chan = Channel::new_outbound(&feeest, &keys_provider, their_node_id, 10000000, 100000, 42, Arc::clone(&logger), &config).unwrap(); // Nothing uses their network key in this test
 		chan.their_to_self_delay = 144;
 		chan.our_dust_limit_satoshis = 546;