Merge pull request #1226 from TheBlueMatt/2022-01-bindings-no-std
[rust-lightning] / lightning / src / routing / network_graph.rs
index 4d33bbdee9278717525c9991805245280bc22137..0b09b74aa9a484db8912587accd83e9f2ff7434a 100644 (file)
@@ -43,6 +43,13 @@ use sync::Mutex;
 use core::ops::Deref;
 use bitcoin::hashes::hex::ToHex;
 
+#[cfg(feature = "std")]
+use std::time::{SystemTime, UNIX_EPOCH};
+
+/// We remove stale channel directional info two weeks after the last update, per BOLT 7's
+/// suggestion.
+const STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS: u64 = 60 * 60 * 24 * 14;
+
 /// The maximum number of extra bytes which we do not understand in a gossip message before we will
 /// refuse to relay the message.
 const MAX_EXCESS_BYTES_FOR_RELAY: usize = 1024;
@@ -242,6 +249,14 @@ where C::Target: chain::Access, L::Target: Logger
                self.chain_access = chain_access;
        }
 
+       /// Gets a reference to the underlying [`NetworkGraph`] which was provided in
+       /// [`NetGraphMsgHandler::new`].
+       ///
+       /// (C-not exported) as bindings don't support a reference-to-a-reference yet
+       pub fn network_graph(&self) -> &G {
+               &self.network_graph
+       }
+
        /// Returns true when a full routing table sync should be performed with a peer.
        fn should_request_full_sync(&self, _node_id: &PublicKey) -> bool {
                //TODO: Determine whether to request a full sync based on the network map.
@@ -628,6 +643,10 @@ pub struct ChannelInfo {
        /// Everything else is useful only for sending out for initial routing sync.
        /// Not stored if contains excess data to prevent DoS.
        pub announcement_message: Option<ChannelAnnouncement>,
+       /// The timestamp when we received the announcement, if we are running with feature = "std"
+       /// (which we can probably assume we are - no-std environments probably won't have a full
+       /// network graph in memory!).
+       announcement_received_time: u64,
 }
 
 impl fmt::Display for ChannelInfo {
@@ -640,6 +659,7 @@ impl fmt::Display for ChannelInfo {
 
 impl_writeable_tlv_based!(ChannelInfo, {
        (0, features, required),
+       (1, announcement_received_time, (default_value, 0)),
        (2, node_one, required),
        (4, one_to_two, required),
        (6, node_two, required),
@@ -847,8 +867,13 @@ impl NetworkGraph {
                        None => Err(LightningError{err: "No existing channels for node_announcement".to_owned(), action: ErrorAction::IgnoreError}),
                        Some(node) => {
                                if let Some(node_info) = node.announcement_info.as_ref() {
-                                       if node_info.last_update  >= msg.timestamp {
+                                       // The timestamp field is somewhat of a misnomer - the BOLTs use it to order
+                                       // updates to ensure you always have the latest one, only vaguely suggesting
+                                       // that it be at least the current time.
+                                       if node_info.last_update  > msg.timestamp {
                                                return Err(LightningError{err: "Update older than last processed update".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                                       } else if node_info.last_update  == msg.timestamp {
+                                               return Err(LightningError{err: "Update had the same timestamp as last processed update".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
                                        }
                                }
 
@@ -947,6 +972,13 @@ impl NetworkGraph {
                        },
                };
 
+               #[allow(unused_mut, unused_assignments)]
+               let mut announcement_received_time = 0;
+               #[cfg(feature = "std")]
+               {
+                       announcement_received_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+               }
+
                let chan_info = ChannelInfo {
                                features: msg.features.clone(),
                                node_one: NodeId::from_pubkey(&msg.node_id_1),
@@ -956,6 +988,7 @@ impl NetworkGraph {
                                capacity_sats: utxo_value,
                                announcement_message: if msg.excess_data.len() <= MAX_EXCESS_BYTES_FOR_RELAY
                                        { full_msg.cloned() } else { None },
+                               announcement_received_time,
                        };
 
                let mut channels = self.channels.write().unwrap();
@@ -977,7 +1010,7 @@ impl NetworkGraph {
                                        Self::remove_channel_in_nodes(&mut nodes, &entry.get(), msg.short_channel_id);
                                        *entry.get_mut() = chan_info;
                                } else {
-                                       return Err(LightningError{err: "Already have knowledge of channel".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)})
+                                       return Err(LightningError{err: "Already have knowledge of channel".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
                                }
                        },
                        BtreeEntry::Vacant(entry) => {
@@ -1040,12 +1073,78 @@ impl NetworkGraph {
                }
        }
 
+       #[cfg(feature = "std")]
+       /// Removes information about channels that we haven't heard any updates about in some time.
+       /// This can be used regularly to prune the network graph of channels that likely no longer
+       /// exist.
+       ///
+       /// While there is no formal requirement that nodes regularly re-broadcast their channel
+       /// updates every two weeks, the non-normative section of BOLT 7 currently suggests that
+       /// pruning occur for updates which are at least two weeks old, which we implement here.
+       ///
+       /// Note that for users of the `lightning-background-processor` crate this method may be
+       /// automatically called regularly for you.
+       ///
+       /// This method is only available with the `std` feature. See
+       /// [`NetworkGraph::remove_stale_channels_with_time`] for `no-std` use.
+       pub fn remove_stale_channels(&self) {
+               let time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+               self.remove_stale_channels_with_time(time);
+       }
+
+       /// Removes information about channels that we haven't heard any updates about in some time.
+       /// This can be used regularly to prune the network graph of channels that likely no longer
+       /// exist.
+       ///
+       /// While there is no formal requirement that nodes regularly re-broadcast their channel
+       /// updates every two weeks, the non-normative section of BOLT 7 currently suggests that
+       /// pruning occur for updates which are at least two weeks old, which we implement here.
+       ///
+       /// This function takes the current unix time as an argument. For users with the `std` feature
+       /// enabled, [`NetworkGraph::remove_stale_channels`] may be preferable.
+       pub fn remove_stale_channels_with_time(&self, current_time_unix: u64) {
+               let mut channels = self.channels.write().unwrap();
+               // Time out if we haven't received an update in at least 14 days.
+               if current_time_unix > u32::max_value() as u64 { return; } // Remove by 2106
+               if current_time_unix < STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS { return; }
+               let min_time_unix: u32 = (current_time_unix - STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS) as u32;
+               // Sadly BTreeMap::retain was only stabilized in 1.53 so we can't switch to it for some
+               // time.
+               let mut scids_to_remove = Vec::new();
+               for (scid, info) in channels.iter_mut() {
+                       if info.one_to_two.is_some() && info.one_to_two.as_ref().unwrap().last_update < min_time_unix {
+                               info.one_to_two = None;
+                       }
+                       if info.two_to_one.is_some() && info.two_to_one.as_ref().unwrap().last_update < min_time_unix {
+                               info.two_to_one = None;
+                       }
+                       if info.one_to_two.is_none() && info.two_to_one.is_none() {
+                               // We check the announcement_received_time here to ensure we don't drop
+                               // announcements that we just received and are just waiting for our peer to send a
+                               // channel_update for.
+                               if info.announcement_received_time < min_time_unix as u64 {
+                                       scids_to_remove.push(*scid);
+                               }
+                       }
+               }
+               if !scids_to_remove.is_empty() {
+                       let mut nodes = self.nodes.write().unwrap();
+                       for scid in scids_to_remove {
+                               let info = channels.remove(&scid).expect("We just accessed this scid, it should be present");
+                               Self::remove_channel_in_nodes(&mut nodes, &info, scid);
+                       }
+               }
+       }
+
        /// For an already known (from announcement) channel, update info about one of the directions
        /// of the channel.
        ///
        /// You probably don't want to call this directly, instead relying on a NetGraphMsgHandler's
        /// RoutingMessageHandler implementation to call it indirectly. This may be useful to accept
        /// routing messages from a source using a protocol other than the lightning P2P protocol.
+       ///
+       /// If built with `no-std`, any updates with a timestamp more than two weeks in the past or
+       /// materially in the future will be rejected.
        pub fn update_channel<T: secp256k1::Verification>(&self, msg: &msgs::ChannelUpdate, secp_ctx: &Secp256k1<T>) -> Result<(), LightningError> {
                self.update_channel_intern(&msg.contents, Some(&msg), Some((&msg.signature, secp_ctx)))
        }
@@ -1053,6 +1152,9 @@ impl NetworkGraph {
        /// For an already known (from announcement) channel, update info about one of the directions
        /// of the channel without verifying the associated signatures. Because we aren't given the
        /// associated signatures here we cannot relay the channel update to any of our peers.
+       ///
+       /// If built with `no-std`, any updates with a timestamp more than two weeks in the past or
+       /// materially in the future will be rejected.
        pub fn update_channel_unsigned(&self, msg: &msgs::UnsignedChannelUpdate) -> Result<(), LightningError> {
                self.update_channel_intern(msg, None, None::<(&secp256k1::Signature, &Secp256k1<secp256k1::VerifyOnly>)>)
        }
@@ -1062,6 +1164,19 @@ impl NetworkGraph {
                let chan_enabled = msg.flags & (1 << 1) != (1 << 1);
                let chan_was_enabled;
 
+               #[cfg(all(feature = "std", not(test), not(feature = "_test_utils")))]
+               {
+                       // Note that many tests rely on being able to set arbitrarily old timestamps, thus we
+                       // disable this check during tests!
+                       let time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+                       if (msg.timestamp as u64) < time - STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS {
+                               return Err(LightningError{err: "channel_update is older than two weeks old".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                       }
+                       if msg.timestamp as u64 > time + 60 * 60 * 24 {
+                               return Err(LightningError{err: "channel_update has a timestamp more than a day in the future".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                       }
+               }
+
                let mut channels = self.channels.write().unwrap();
                match channels.get_mut(&msg.short_channel_id) {
                        None => return Err(LightningError{err: "Couldn't find channel for update".to_owned(), action: ErrorAction::IgnoreError}),
@@ -1082,8 +1197,16 @@ impl NetworkGraph {
                                macro_rules! maybe_update_channel_info {
                                        ( $target: expr, $src_node: expr) => {
                                                if let Some(existing_chan_info) = $target.as_ref() {
-                                                       if existing_chan_info.last_update >= msg.timestamp {
+                                                       // The timestamp field is somewhat of a misnomer - the BOLTs use it to
+                                                       // order updates to ensure you always have the latest one, only
+                                                       // suggesting  that it be at least the current time. For
+                                                       // channel_updates specifically, the BOLTs discuss the possibility of
+                                                       // pruning based on the timestamp field being more than two weeks old,
+                                                       // but only in the non-normative section.
+                                                       if existing_chan_info.last_update > msg.timestamp {
                                                                return Err(LightningError{err: "Update older than last processed update".to_owned(), action: ErrorAction::IgnoreAndLog(Level::Gossip)});
+                                                       } else if existing_chan_info.last_update == msg.timestamp {
+                                                               return Err(LightningError{err: "Update had same timestamp as last processed update".to_owned(), action: ErrorAction::IgnoreDuplicateGossip});
                                                        }
                                                        chan_was_enabled = existing_chan_info.enabled;
                                                } else {
@@ -1237,11 +1360,13 @@ mod tests {
        use util::events::{Event, EventHandler, MessageSendEvent, MessageSendEventsProvider};
        use util::scid_utils::scid_from_parts;
 
+       use super::STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS;
+
        use bitcoin::hashes::sha256d::Hash as Sha256dHash;
        use bitcoin::hashes::Hash;
        use bitcoin::network::constants::Network;
        use bitcoin::blockdata::constants::genesis_block;
-       use bitcoin::blockdata::script::Builder;
+       use bitcoin::blockdata::script::{Builder, Script};
        use bitcoin::blockdata::transaction::TxOut;
        use bitcoin::blockdata::opcodes;
 
@@ -1282,36 +1407,95 @@ mod tests {
                assert!(!net_graph_msg_handler.should_request_full_sync(&node_id));
        }
 
-       #[test]
-       fn handling_node_announcements() {
-               let network_graph = create_network_graph();
-               let (secp_ctx, net_graph_msg_handler) = create_net_graph_msg_handler(&network_graph);
-
-               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
-               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-               let zero_hash = Sha256dHash::hash(&[0; 32]);
-               let first_announcement_time = 500;
-
+       fn get_signed_node_announcement<F: Fn(&mut UnsignedNodeAnnouncement)>(f: F, node_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> NodeAnnouncement {
+               let node_id = PublicKey::from_secret_key(&secp_ctx, node_key);
                let mut unsigned_announcement = UnsignedNodeAnnouncement {
                        features: NodeFeatures::known(),
-                       timestamp: first_announcement_time,
-                       node_id: node_id_1,
+                       timestamp: 100,
+                       node_id: node_id,
                        rgb: [0; 3],
                        alias: [0; 32],
                        addresses: Vec::new(),
                        excess_address_data: Vec::new(),
                        excess_data: Vec::new(),
                };
-               let mut msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = NodeAnnouncement {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_announcement.clone()
+               f(&mut unsigned_announcement);
+               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
+               NodeAnnouncement {
+                       signature: secp_ctx.sign(&msghash, node_key),
+                       contents: unsigned_announcement
+               }
+       }
+
+       fn get_signed_channel_announcement<F: Fn(&mut UnsignedChannelAnnouncement)>(f: F, node_1_key: &SecretKey, node_2_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> ChannelAnnouncement {
+               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_key);
+               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_key);
+               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
+               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
+
+               let mut unsigned_announcement = UnsignedChannelAnnouncement {
+                       features: ChannelFeatures::known(),
+                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+                       short_channel_id: 0,
+                       node_id_1,
+                       node_id_2,
+                       bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
+                       bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
+                       excess_data: Vec::new(),
+               };
+               f(&mut unsigned_announcement);
+               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
+               ChannelAnnouncement {
+                       node_signature_1: secp_ctx.sign(&msghash, node_1_key),
+                       node_signature_2: secp_ctx.sign(&msghash, node_2_key),
+                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
+                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
+                       contents: unsigned_announcement,
+               }
+       }
+
+       fn get_channel_script(secp_ctx: &Secp256k1<secp256k1::All>) -> Script {
+               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
+               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
+               Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
+                             .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_1_btckey).serialize())
+                             .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_2_btckey).serialize())
+                             .push_opcode(opcodes::all::OP_PUSHNUM_2)
+                             .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script()
+                             .to_v0_p2wsh()
+       }
+
+       fn get_signed_channel_update<F: Fn(&mut UnsignedChannelUpdate)>(f: F, node_key: &SecretKey, secp_ctx: &Secp256k1<secp256k1::All>) -> ChannelUpdate {
+               let mut unsigned_channel_update = UnsignedChannelUpdate {
+                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
+                       short_channel_id: 0,
+                       timestamp: 100,
+                       flags: 0,
+                       cltv_expiry_delta: 144,
+                       htlc_minimum_msat: 1_000_000,
+                       htlc_maximum_msat: OptionalField::Absent,
+                       fee_base_msat: 10_000,
+                       fee_proportional_millionths: 20,
+                       excess_data: Vec::new()
                };
+               f(&mut unsigned_channel_update);
+               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
+               ChannelUpdate {
+                       signature: secp_ctx.sign(&msghash, node_key),
+                       contents: unsigned_channel_update
+               }
+       }
+
+       #[test]
+       fn handling_node_announcements() {
+               let network_graph = create_network_graph();
+               let (secp_ctx, net_graph_msg_handler) = create_net_graph_msg_handler(&network_graph);
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+               let zero_hash = Sha256dHash::hash(&[0; 32]);
 
+               let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!("No existing channels for node_announcement", e.err)
@@ -1319,25 +1503,7 @@ mod tests {
 
                {
                        // Announce a channel to add a corresponding node.
-                       let unsigned_announcement = UnsignedChannelAnnouncement {
-                               features: ChannelFeatures::known(),
-                               chain_hash: genesis_block(Network::Testnet).header.block_hash(),
-                               short_channel_id: 0,
-                               node_id_1,
-                               node_id_2,
-                               bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                               bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                               excess_data: Vec::new(),
-                       };
-
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_announcement = ChannelAnnouncement {
-                               node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                               node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                               bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                               bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                               contents: unsigned_announcement.clone(),
-                       };
+                       let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                                Ok(res) => assert!(res),
                                _ => panic!()
@@ -1353,34 +1519,27 @@ mod tests {
                match net_graph_msg_handler.handle_node_announcement(
                        &NodeAnnouncement {
                                signature: secp_ctx.sign(&fake_msghash, node_1_privkey),
-                               contents: unsigned_announcement.clone()
+                               contents: valid_announcement.contents.clone()
                }) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Invalid signature from remote node")
                };
 
-               unsigned_announcement.timestamp += 1000;
-               unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let announcement_with_data = NodeAnnouncement {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_announcement.clone()
-               };
+               let announcement_with_data = get_signed_node_announcement(|unsigned_announcement| {
+                       unsigned_announcement.timestamp += 1000;
+                       unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
+               }, node_1_privkey, &secp_ctx);
                // Return false because contains excess data.
                match net_graph_msg_handler.handle_node_announcement(&announcement_with_data) {
                        Ok(res) => assert!(!res),
                        Err(_) => panic!()
                };
-               unsigned_announcement.excess_data = Vec::new();
 
                // Even though previous announcement was not relayed further, we still accepted it,
                // so we now won't accept announcements before the previous one.
-               unsigned_announcement.timestamp -= 10;
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let outdated_announcement = NodeAnnouncement {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_announcement.clone()
-               };
+               let outdated_announcement = get_signed_node_announcement(|unsigned_announcement| {
+                       unsigned_announcement.timestamp += 1000 - 10;
+               }, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_node_announcement(&outdated_announcement) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Update older than last processed update")
@@ -1394,37 +1553,9 @@ mod tests {
 
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-
-               let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
-                  .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_1_btckey).serialize())
-                  .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_2_btckey).serialize())
-                  .push_opcode(opcodes::all::OP_PUSHNUM_2)
-                  .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
 
-
-               let mut unsigned_announcement = UnsignedChannelAnnouncement {
-                       features: ChannelFeatures::known(),
-                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
-                       short_channel_id: 0,
-                       node_id_1,
-                       node_id_2,
-                       bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                       bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                       excess_data: Vec::new(),
-               };
-
-               let mut msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let good_script = get_channel_script(&secp_ctx);
+               let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
 
                // Test if the UTXO lookups were not supported
                let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
@@ -1435,7 +1566,7 @@ mod tests {
                };
 
                {
-                       match network_graph.read_only().channels().get(&unsigned_announcement.short_channel_id) {
+                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
                                None => panic!(),
                                Some(_) => ()
                        };
@@ -1453,41 +1584,27 @@ mod tests {
                *chain_source.utxo_ret.lock().unwrap() = Err(chain::AccessError::UnknownTx);
                let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
                net_graph_msg_handler = NetGraphMsgHandler::new(&network_graph, Some(chain_source.clone()), Arc::clone(&logger));
-               unsigned_announcement.short_channel_id += 1;
-
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
 
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.short_channel_id += 1;
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Channel announced without corresponding UTXO entry")
                };
 
                // Now test if the transaction is found in the UTXO set and the script is correct.
-               unsigned_announcement.short_channel_id += 1;
                *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: 0, script_pubkey: good_script.clone() });
-
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.short_channel_id += 2;
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                        Ok(res) => assert!(res),
                        _ => panic!()
                };
 
                {
-                       match network_graph.read_only().channels().get(&unsigned_announcement.short_channel_id) {
+                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
                                None => panic!(),
                                Some(_) => ()
                        };
@@ -1503,21 +1620,16 @@ mod tests {
 
                // But if it is confirmed, replace the channel
                *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: 0, script_pubkey: good_script });
-               unsigned_announcement.features = ChannelFeatures::empty();
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.features = ChannelFeatures::empty();
+                       unsigned_announcement.short_channel_id += 2;
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                        Ok(res) => assert!(res),
                        _ => panic!()
                };
                {
-                       match network_graph.read_only().channels().get(&unsigned_announcement.short_channel_id) {
+                       match network_graph.read_only().channels().get(&valid_announcement.contents.short_channel_id) {
                                Some(channel_entry) => {
                                        assert_eq!(channel_entry.features, ChannelFeatures::empty());
                                },
@@ -1526,43 +1638,23 @@ mod tests {
                }
 
                // Don't relay valid channels with excess data
-               unsigned_announcement.short_channel_id += 1;
-               unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                       unsigned_announcement.short_channel_id += 3;
+                       unsigned_announcement.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
+               }, node_1_privkey, node_2_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                        Ok(res) => assert!(!res),
                        _ => panic!()
                };
 
-               unsigned_announcement.excess_data = Vec::new();
-               let invalid_sig_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_1_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let mut invalid_sig_announcement = valid_announcement.clone();
+               invalid_sig_announcement.contents.excess_data = Vec::new();
                match net_graph_msg_handler.handle_channel_announcement(&invalid_sig_announcement) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Invalid signature from remote node")
                };
 
-               unsigned_announcement.node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let channel_to_itself_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_2_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let channel_to_itself_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_announcement(&channel_to_itself_announcement) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Channel announcement node had a channel with itself")
@@ -1579,43 +1671,17 @@ mod tests {
 
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
 
-               let zero_hash = Sha256dHash::hash(&[0; 32]);
-               let short_channel_id = 0;
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
                let amount_sats = 1000_000;
+               let short_channel_id;
 
                {
                        // Announce a channel we will update
-                       let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
-                          .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_1_btckey).serialize())
-                          .push_slice(&PublicKey::from_secret_key(&secp_ctx, node_2_btckey).serialize())
-                          .push_opcode(opcodes::all::OP_PUSHNUM_2)
-                          .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
+                       let good_script = get_channel_script(&secp_ctx);
                        *chain_source.utxo_ret.lock().unwrap() = Ok(TxOut { value: amount_sats, script_pubkey: good_script.clone() });
-                       let unsigned_announcement = UnsignedChannelAnnouncement {
-                               features: ChannelFeatures::empty(),
-                               chain_hash,
-                               short_channel_id,
-                               node_id_1,
-                               node_id_2,
-                               bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                               bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                               excess_data: Vec::new(),
-                       };
 
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_channel_announcement = ChannelAnnouncement {
-                               node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                               node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                               bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                               bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                               contents: unsigned_announcement.clone(),
-                       };
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
                        match net_graph_msg_handler.handle_channel_announcement(&valid_channel_announcement) {
                                Ok(_) => (),
                                Err(_) => panic!()
@@ -1623,24 +1689,7 @@ mod tests {
 
                }
 
-               let mut unsigned_channel_update = UnsignedChannelUpdate {
-                       chain_hash,
-                       short_channel_id,
-                       timestamp: 100,
-                       flags: 0,
-                       cltv_expiry_delta: 144,
-                       htlc_minimum_msat: 1000000,
-                       htlc_maximum_msat: OptionalField::Absent,
-                       fee_base_msat: 10000,
-                       fee_proportional_millionths: 20,
-                       excess_data: Vec::new()
-               };
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               let valid_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
-
+               let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                        Ok(res) => assert!(res),
                        _ => panic!()
@@ -1656,85 +1705,63 @@ mod tests {
                        };
                }
 
-               unsigned_channel_update.timestamp += 100;
-               unsigned_channel_update.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               let valid_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 100;
+                       unsigned_channel_update.excess_data.resize(MAX_EXCESS_BYTES_FOR_RELAY + 1, 0);
+               }, node_1_privkey, &secp_ctx);
                // Return false because contains excess data
                match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                        Ok(res) => assert!(!res),
                        _ => panic!()
                };
-               unsigned_channel_update.timestamp += 10;
-
-               unsigned_channel_update.short_channel_id += 1;
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               let valid_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
 
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 110;
+                       unsigned_channel_update.short_channel_id += 1;
+               }, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Couldn't find channel for update")
                };
-               unsigned_channel_update.short_channel_id = short_channel_id;
-
-               unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(MAX_VALUE_MSAT + 1);
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               let valid_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
 
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(MAX_VALUE_MSAT + 1);
+                       unsigned_channel_update.timestamp += 110;
+               }, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "htlc_maximum_msat is larger than maximum possible msats")
                };
-               unsigned_channel_update.htlc_maximum_msat = OptionalField::Absent;
-
-               unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(amount_sats * 1000 + 1);
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               let valid_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
 
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.htlc_maximum_msat = OptionalField::Present(amount_sats * 1000 + 1);
+                       unsigned_channel_update.timestamp += 110;
+               }, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "htlc_maximum_msat is larger than channel capacity or capacity is bogus")
                };
-               unsigned_channel_update.htlc_maximum_msat = OptionalField::Absent;
 
                // Even though previous update was not relayed further, we still accepted it,
                // so we now won't accept update before the previous one.
-               unsigned_channel_update.timestamp -= 10;
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-               let valid_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
-
+               let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 100;
+               }, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                        Ok(_) => panic!(),
-                       Err(e) => assert_eq!(e.err, "Update older than last processed update")
+                       Err(e) => assert_eq!(e.err, "Update had same timestamp as last processed update")
                };
-               unsigned_channel_update.timestamp += 500;
 
+               let mut invalid_sig_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                       unsigned_channel_update.timestamp += 500;
+               }, node_1_privkey, &secp_ctx);
+               let zero_hash = Sha256dHash::hash(&[0; 32]);
                let fake_msghash = hash_to_message!(&zero_hash);
-               let invalid_sig_channel_update = ChannelUpdate {
-                       signature: secp_ctx.sign(&fake_msghash, node_1_privkey),
-                       contents: unsigned_channel_update.clone()
-               };
-
+               invalid_sig_channel_update.signature = secp_ctx.sign(&fake_msghash, node_1_privkey);
                match net_graph_msg_handler.handle_channel_update(&invalid_sig_channel_update) {
                        Ok(_) => panic!(),
                        Err(e) => assert_eq!(e.err, "Invalid signature from remote node")
                };
-
        }
 
        #[test]
@@ -1748,62 +1775,22 @@ mod tests {
 
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-
-               let short_channel_id = 0;
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
 
                {
                        // There is no nodes in the table at the beginning.
                        assert_eq!(network_graph.read_only().nodes().len(), 0);
                }
 
+               let short_channel_id;
                {
                        // Announce a channel we will update
-                       let unsigned_announcement = UnsignedChannelAnnouncement {
-                               features: ChannelFeatures::empty(),
-                               chain_hash,
-                               short_channel_id,
-                               node_id_1,
-                               node_id_2,
-                               bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                               bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                               excess_data: Vec::new(),
-                       };
-
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_channel_announcement = ChannelAnnouncement {
-                               node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                               node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                               bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                               bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                               contents: unsigned_announcement.clone(),
-                       };
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
                        let chain_source: Option<&test_utils::TestChainSource> = None;
                        assert!(network_graph.update_channel_from_announcement(&valid_channel_announcement, &chain_source, &secp_ctx).is_ok());
                        assert!(network_graph.read_only().channels().get(&short_channel_id).is_some());
 
-                       let unsigned_channel_update = UnsignedChannelUpdate {
-                               chain_hash,
-                               short_channel_id,
-                               timestamp: 100,
-                               flags: 0,
-                               cltv_expiry_delta: 144,
-                               htlc_minimum_msat: 1000000,
-                               htlc_maximum_msat: OptionalField::Absent,
-                               fee_base_msat: 10000,
-                               fee_proportional_millionths: 20,
-                               excess_data: Vec::new()
-                       };
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-                       let valid_channel_update = ChannelUpdate {
-                               signature: secp_ctx.sign(&msghash, node_1_privkey),
-                               contents: unsigned_channel_update.clone()
-                       };
-
+                       let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
                        assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_none());
 
                        net_graph_msg_handler.handle_event(&Event::PaymentPathFailed {
@@ -1858,28 +1845,73 @@ mod tests {
                }
 
                // Permanent closing deletes a channel
+               net_graph_msg_handler.handle_event(&Event::PaymentPathFailed {
+                       payment_id: None,
+                       payment_hash: PaymentHash([0; 32]),
+                       rejected_by_dest: false,
+                       all_paths_failed: true,
+                       path: vec![],
+                       network_update: Some(NetworkUpdate::ChannelClosed {
+                               short_channel_id,
+                               is_permanent: true,
+                       }),
+                       short_channel_id: None,
+                       retry: None,
+                       error_code: None,
+                       error_data: None,
+               });
+
+               assert_eq!(network_graph.read_only().channels().len(), 0);
+               // Nodes are also deleted because there are no associated channels anymore
+               assert_eq!(network_graph.read_only().nodes().len(), 0);
+               // TODO: Test NetworkUpdate::NodeFailure, which is not implemented yet.
+       }
+
+       #[test]
+       fn test_channel_timeouts() {
+               // Test the removal of channels with `remove_stale_channels`.
+               let logger = test_utils::TestLogger::new();
+               let chain_source = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
+               let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
+               let network_graph = NetworkGraph::new(genesis_hash);
+               let net_graph_msg_handler = NetGraphMsgHandler::new(&network_graph, Some(chain_source.clone()), &logger);
+               let secp_ctx = Secp256k1::new();
+
+               let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
+               let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
+
+               let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+               let short_channel_id = valid_channel_announcement.contents.short_channel_id;
+               let chain_source: Option<&test_utils::TestChainSource> = None;
+               assert!(network_graph.update_channel_from_announcement(&valid_channel_announcement, &chain_source, &secp_ctx).is_ok());
+               assert!(network_graph.read_only().channels().get(&short_channel_id).is_some());
+
+               let valid_channel_update = get_signed_channel_update(|_| {}, node_1_privkey, &secp_ctx);
+               assert!(net_graph_msg_handler.handle_channel_update(&valid_channel_update).is_ok());
+               assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_some());
+
+               network_graph.remove_stale_channels_with_time(100 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
+               assert_eq!(network_graph.read_only().channels().len(), 1);
+               assert_eq!(network_graph.read_only().nodes().len(), 2);
+
+               network_graph.remove_stale_channels_with_time(101 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
+               #[cfg(feature = "std")]
                {
-                       net_graph_msg_handler.handle_event(&Event::PaymentPathFailed {
-                               payment_id: None,
-                               payment_hash: PaymentHash([0; 32]),
-                               rejected_by_dest: false,
-                               all_paths_failed: true,
-                               path: vec![],
-                               network_update: Some(NetworkUpdate::ChannelClosed {
-                                       short_channel_id,
-                                       is_permanent: true,
-                               }),
-                               short_channel_id: None,
-                               retry: None,
-                               error_code: None,
-                               error_data: None,
-                       });
+                       // In std mode, a further check is performed before fully removing the channel -
+                       // the channel_announcement must have been received at least two weeks ago. We
+                       // fudge that here by indicating the time has jumped two weeks. Note that the
+                       // directional channel information will have been removed already..
+                       assert_eq!(network_graph.read_only().channels().len(), 1);
+                       assert_eq!(network_graph.read_only().nodes().len(), 2);
+                       assert!(network_graph.read_only().channels().get(&short_channel_id).unwrap().one_to_two.is_none());
 
-                       assert_eq!(network_graph.read_only().channels().len(), 0);
-                       // Nodes are also deleted because there are no associated channels anymore
-                       assert_eq!(network_graph.read_only().nodes().len(), 0);
+                       use std::time::{SystemTime, UNIX_EPOCH};
+                       let announcement_time = SystemTime::now().duration_since(UNIX_EPOCH).expect("Time must be > 1970").as_secs();
+                       network_graph.remove_stale_channels_with_time(announcement_time + 1 + STALE_CHANNEL_UPDATE_AGE_LIMIT_SECS);
                }
-               // TODO: Test NetworkUpdate::NodeFailure, which is not implemented yet.
+
+               assert_eq!(network_graph.read_only().channels().len(), 0);
+               assert_eq!(network_graph.read_only().nodes().len(), 0);
        }
 
        #[test]
@@ -1888,39 +1920,16 @@ mod tests {
                let (secp_ctx, net_graph_msg_handler) = create_net_graph_msg_handler(&network_graph);
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-
-               let short_channel_id = 1;
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
 
                // Channels were not announced yet.
                let channels_with_announcements = net_graph_msg_handler.get_next_channel_announcements(0, 1);
                assert_eq!(channels_with_announcements.len(), 0);
 
+               let short_channel_id;
                {
                        // Announce a channel we will update
-                       let unsigned_announcement = UnsignedChannelAnnouncement {
-                               features: ChannelFeatures::empty(),
-                               chain_hash,
-                               short_channel_id,
-                               node_id_1,
-                               node_id_2,
-                               bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                               bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                               excess_data: Vec::new(),
-                       };
-
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_channel_announcement = ChannelAnnouncement {
-                               node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                               node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                               bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                               bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                               contents: unsigned_announcement.clone(),
-                       };
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
+                       short_channel_id = valid_channel_announcement.contents.short_channel_id;
                        match net_graph_msg_handler.handle_channel_announcement(&valid_channel_announcement) {
                                Ok(_) => (),
                                Err(_) => panic!()
@@ -1941,23 +1950,9 @@ mod tests {
 
                {
                        // Valid channel update
-                       let unsigned_channel_update = UnsignedChannelUpdate {
-                               chain_hash,
-                               short_channel_id,
-                               timestamp: 101,
-                               flags: 0,
-                               cltv_expiry_delta: 144,
-                               htlc_minimum_msat: 1000000,
-                               htlc_maximum_msat: OptionalField::Absent,
-                               fee_base_msat: 10000,
-                               fee_proportional_millionths: 20,
-                               excess_data: Vec::new()
-                       };
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-                       let valid_channel_update = ChannelUpdate {
-                               signature: secp_ctx.sign(&msghash, node_1_privkey),
-                               contents: unsigned_channel_update.clone()
-                       };
+                       let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                               unsigned_channel_update.timestamp = 101;
+                       }, node_1_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                                Ok(_) => (),
                                Err(_) => panic!()
@@ -1975,26 +1970,12 @@ mod tests {
                        panic!();
                }
 
-
                {
                        // Channel update with excess data.
-                       let unsigned_channel_update = UnsignedChannelUpdate {
-                               chain_hash,
-                               short_channel_id,
-                               timestamp: 102,
-                               flags: 0,
-                               cltv_expiry_delta: 144,
-                               htlc_minimum_msat: 1000000,
-                               htlc_maximum_msat: OptionalField::Absent,
-                               fee_base_msat: 10000,
-                               fee_proportional_millionths: 20,
-                               excess_data: [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec()
-                       };
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_channel_update.encode()[..])[..]);
-                       let valid_channel_update = ChannelUpdate {
-                               signature: secp_ctx.sign(&msghash, node_1_privkey),
-                               contents: unsigned_channel_update.clone()
-                       };
+                       let valid_channel_update = get_signed_channel_update(|unsigned_channel_update| {
+                               unsigned_channel_update.timestamp = 102;
+                               unsigned_channel_update.excess_data = [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec();
+                       }, node_1_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
                                Ok(_) => (),
                                Err(_) => panic!()
@@ -2024,12 +2005,6 @@ mod tests {
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
                let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-
-               let short_channel_id = 1;
-               let chain_hash = genesis_block(Network::Testnet).header.block_hash();
 
                // No nodes yet.
                let next_announcements = net_graph_msg_handler.get_next_node_announcements(None, 10);
@@ -2037,25 +2012,7 @@ mod tests {
 
                {
                        // Announce a channel to add 2 nodes
-                       let unsigned_announcement = UnsignedChannelAnnouncement {
-                               features: ChannelFeatures::empty(),
-                               chain_hash,
-                               short_channel_id,
-                               node_id_1,
-                               node_id_2,
-                               bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                               bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                               excess_data: Vec::new(),
-                       };
-
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_channel_announcement = ChannelAnnouncement {
-                               node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                               node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                               bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                               bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                               contents: unsigned_announcement.clone(),
-                       };
+                       let valid_channel_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_channel_announcement(&valid_channel_announcement) {
                                Ok(_) => (),
                                Err(_) => panic!()
@@ -2068,33 +2025,13 @@ mod tests {
                assert_eq!(next_announcements.len(), 0);
 
                {
-                       let mut unsigned_announcement = UnsignedNodeAnnouncement {
-                               features: NodeFeatures::known(),
-                               timestamp: 1000,
-                               node_id: node_id_1,
-                               rgb: [0; 3],
-                               alias: [0; 32],
-                               addresses: Vec::new(),
-                               excess_address_data: Vec::new(),
-                               excess_data: Vec::new(),
-                       };
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_announcement = NodeAnnouncement {
-                               signature: secp_ctx.sign(&msghash, node_1_privkey),
-                               contents: unsigned_announcement.clone()
-                       };
+                       let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
                                Ok(_) => (),
                                Err(_) => panic!()
                        };
 
-                       unsigned_announcement.node_id = node_id_2;
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_announcement = NodeAnnouncement {
-                               signature: secp_ctx.sign(&msghash, node_2_privkey),
-                               contents: unsigned_announcement.clone()
-                       };
-
+                       let valid_announcement = get_signed_node_announcement(|_| {}, node_2_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
                                Ok(_) => (),
                                Err(_) => panic!()
@@ -2110,21 +2047,10 @@ mod tests {
 
                {
                        // Later announcement which should not be relayed (excess data) prevent us from sharing a node
-                       let unsigned_announcement = UnsignedNodeAnnouncement {
-                               features: NodeFeatures::known(),
-                               timestamp: 1010,
-                               node_id: node_id_2,
-                               rgb: [0; 3],
-                               alias: [0; 32],
-                               addresses: Vec::new(),
-                               excess_address_data: Vec::new(),
-                               excess_data: [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec(),
-                       };
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_announcement = NodeAnnouncement {
-                               signature: secp_ctx.sign(&msghash, node_2_privkey),
-                               contents: unsigned_announcement.clone()
-                       };
+                       let valid_announcement = get_signed_node_announcement(|unsigned_announcement| {
+                               unsigned_announcement.timestamp += 10;
+                               unsigned_announcement.excess_data = [1; MAX_EXCESS_BYTES_FOR_RELAY + 1].to_vec();
+                       }, node_2_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
                                Ok(res) => assert!(!res),
                                Err(_) => panic!()
@@ -2142,54 +2068,15 @@ mod tests {
 
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
 
                // Announce a channel to add a corresponding node.
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let unsigned_announcement = UnsignedChannelAnnouncement {
-                       features: ChannelFeatures::known(),
-                       chain_hash: genesis_block(Network::Testnet).header.block_hash(),
-                       short_channel_id: 0,
-                       node_id_1,
-                       node_id_2,
-                       bitcoin_key_1: PublicKey::from_secret_key(&secp_ctx, node_1_btckey),
-                       bitcoin_key_2: PublicKey::from_secret_key(&secp_ctx, node_2_btckey),
-                       excess_data: Vec::new(),
-               };
-
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = ChannelAnnouncement {
-                       node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                       node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                       bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                       bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                       contents: unsigned_announcement.clone(),
-               };
+               let valid_announcement = get_signed_channel_announcement(|_| {}, node_1_privkey, node_2_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                        Ok(res) => assert!(res),
                        _ => panic!()
                };
 
-
-               let node_id = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
-               let unsigned_announcement = UnsignedNodeAnnouncement {
-                       features: NodeFeatures::known(),
-                       timestamp: 100,
-                       node_id,
-                       rgb: [0; 3],
-                       alias: [0; 32],
-                       addresses: Vec::new(),
-                       excess_address_data: Vec::new(),
-                       excess_data: Vec::new(),
-               };
-               let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-               let valid_announcement = NodeAnnouncement {
-                       signature: secp_ctx.sign(&msghash, node_1_privkey),
-                       contents: unsigned_announcement.clone()
-               };
-
+               let valid_announcement = get_signed_node_announcement(|_| {}, node_1_privkey, &secp_ctx);
                match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
                        Ok(_) => (),
                        Err(_) => panic!()
@@ -2347,12 +2234,7 @@ mod tests {
                let chain_hash = genesis_block(Network::Testnet).header.block_hash();
                let node_1_privkey = &SecretKey::from_slice(&[42; 32]).unwrap();
                let node_2_privkey = &SecretKey::from_slice(&[41; 32]).unwrap();
-               let node_1_btckey = &SecretKey::from_slice(&[40; 32]).unwrap();
-               let node_2_btckey = &SecretKey::from_slice(&[39; 32]).unwrap();
-               let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
                let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
-               let bitcoin_key_1 = PublicKey::from_secret_key(&secp_ctx, node_1_btckey);
-               let bitcoin_key_2 = PublicKey::from_secret_key(&secp_ctx, node_2_btckey);
 
                let mut scids: Vec<u64> = vec![
                        scid_from_parts(0xfffffe, 0xffffff, 0xffff).unwrap(), // max
@@ -2368,25 +2250,9 @@ mod tests {
                scids.push(scid_from_parts(108001, 1, 0).unwrap());
 
                for scid in scids {
-                       let unsigned_announcement = UnsignedChannelAnnouncement {
-                               features: ChannelFeatures::known(),
-                               chain_hash: chain_hash.clone(),
-                               short_channel_id: scid,
-                               node_id_1,
-                               node_id_2,
-                               bitcoin_key_1,
-                               bitcoin_key_2,
-                               excess_data: Vec::new(),
-                       };
-
-                       let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
-                       let valid_announcement = ChannelAnnouncement {
-                               node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
-                               node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
-                               bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_btckey),
-                               bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_btckey),
-                               contents: unsigned_announcement.clone(),
-                       };
+                       let valid_announcement = get_signed_channel_announcement(|unsigned_announcement| {
+                               unsigned_announcement.short_channel_id = scid;
+                       }, node_1_privkey, node_2_privkey, &secp_ctx);
                        match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
                                Ok(_) => (),
                                _ => panic!()