Remove user_payment_id
authorValentine Wallace <vwallace@protonmail.com>
Fri, 12 Nov 2021 19:48:39 +0000 (14:48 -0500)
committerValentine Wallace <vwallace@protonmail.com>
Fri, 19 Nov 2021 22:59:09 +0000 (17:59 -0500)
In upcoming commits, we'll be making the payment secret and payment hash/preimage
derivable from info about the payment + a node secret. This means we don't
need to store any info about incoming payments and can eventually get rid of the
channelmanager::pending_inbound_payments map.

fuzz/src/chanmon_consistency.rs
fuzz/src/full_stack.rs
lightning-invoice/src/utils.rs
lightning/src/ln/channelmanager.rs
lightning/src/ln/functional_test_utils.rs
lightning/src/ln/functional_tests.rs
lightning/src/util/events.rs

index acdf3cb3ca2dc3b2f902aa1a323e645b837d2368..8921acdeb8fe3c4e65c6b6bb01534360f40aabdf 100644 (file)
@@ -284,7 +284,7 @@ fn get_payment_secret_hash(dest: &ChanMan, payment_id: &mut u8) -> Option<(Payme
        let mut payment_hash;
        for _ in 0..256 {
                payment_hash = PaymentHash(Sha256::hash(&[*payment_id; 1]).into_inner());
-               if let Ok(payment_secret) = dest.create_inbound_payment_for_hash(payment_hash, None, 3600, 0) {
+               if let Ok(payment_secret) = dest.create_inbound_payment_for_hash(payment_hash, None, 3600) {
                        return Some((payment_secret, payment_hash));
                }
                *payment_id = payment_id.wrapping_add(1);
index 81408b85bb4681d62d7fe43df9b20871a0d597be..c1e9870fd8467e234c654abb2922231bf76505a1 100644 (file)
@@ -529,7 +529,7 @@ pub fn do_test(data: &[u8], logger: &Arc<dyn Logger>) {
                                let payment_hash = PaymentHash(Sha256::from_engine(sha).into_inner());
                                // Note that this may fail - our hashes may collide and we'll end up trying to
                                // double-register the same payment_hash.
-                               let _ = channelmanager.create_inbound_payment_for_hash(payment_hash, None, 1, 0);
+                               let _ = channelmanager.create_inbound_payment_for_hash(payment_hash, None, 1);
                        },
                        9 => {
                                for payment in payments_received.drain(..) {
index b7fdb73f2337e645da21389e0a5b1ad80595518d..f4cc7e713f20063dfb28f371479de5c2655ee70b 100644 (file)
@@ -63,7 +63,6 @@ where
        let (payment_hash, payment_secret) = channelmanager.create_inbound_payment(
                amt_msat,
                DEFAULT_EXPIRY_TIME.try_into().unwrap(),
-               0,
        );
        let our_node_pubkey = channelmanager.get_our_node_id();
        let mut invoice = InvoiceBuilder::new(network)
index 1e60dcdccd401538cf4b2210b030024818e2ef17..3231beebb1163d550c535d8cf183ff887a7d081b 100644 (file)
@@ -413,6 +413,9 @@ struct PeerState {
 ///
 /// For users who don't want to bother doing their own payment preimage storage, we also store that
 /// here.
+///
+/// Note that this struct will be removed entirely soon, in favor of storing no inbound payment data
+/// and instead encoding it in the payment secret.
 struct PendingInboundPayment {
        /// The payment secret that the sender must use for us to accept this payment
        payment_secret: PaymentSecret,
@@ -2887,7 +2890,6 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                                        purpose: events::PaymentPurpose::InvoicePayment {
                                                                                                                payment_preimage: inbound_payment.get().payment_preimage,
                                                                                                                payment_secret: payment_data.payment_secret,
-                                                                                                               user_payment_id: inbound_payment.get().user_payment_id,
                                                                                                        },
                                                                                                        amt: total_value,
                                                                                                });
@@ -4523,7 +4525,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
        }
 
-       fn set_payment_hash_secret_map(&self, payment_hash: PaymentHash, payment_preimage: Option<PaymentPreimage>, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32, user_payment_id: u64) -> Result<PaymentSecret, APIError> {
+       fn set_payment_hash_secret_map(&self, payment_hash: PaymentHash, payment_preimage: Option<PaymentPreimage>, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32) -> Result<PaymentSecret, APIError> {
                assert!(invoice_expiry_delta_secs <= 60*60*24*365); // Sadly bitcoin timestamps are u32s, so panic before 2106
 
                let payment_secret = PaymentSecret(self.keys_manager.get_secure_random_bytes());
@@ -4533,7 +4535,8 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                match payment_secrets.entry(payment_hash) {
                        hash_map::Entry::Vacant(e) => {
                                e.insert(PendingInboundPayment {
-                                       payment_secret, min_value_msat, user_payment_id, payment_preimage,
+                                       payment_secret, min_value_msat, payment_preimage,
+                                       user_payment_id: 0, // For compatibility with version 0.0.103 and earlier
                                        // We assume that highest_seen_timestamp is pretty close to the current time -
                                        // its updated when we receive a new block with the maximum time we've seen in
                                        // a header. It should never be more than two hours in the future.
@@ -4565,12 +4568,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// [`PaymentReceived`]: events::Event::PaymentReceived
        /// [`PaymentReceived::payment_preimage`]: events::Event::PaymentReceived::payment_preimage
        /// [`create_inbound_payment_for_hash`]: Self::create_inbound_payment_for_hash
-       pub fn create_inbound_payment(&self, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32, user_payment_id: u64) -> (PaymentHash, PaymentSecret) {
+       pub fn create_inbound_payment(&self, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32) -> (PaymentHash, PaymentSecret) {
                let payment_preimage = PaymentPreimage(self.keys_manager.get_secure_random_bytes());
                let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
 
                (payment_hash,
-                       self.set_payment_hash_secret_map(payment_hash, Some(payment_preimage), min_value_msat, invoice_expiry_delta_secs, user_payment_id)
+                       self.set_payment_hash_secret_map(payment_hash, Some(payment_preimage), min_value_msat, invoice_expiry_delta_secs)
                                .expect("RNG Generated Duplicate PaymentHash"))
        }
 
@@ -4584,12 +4587,6 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// The [`PaymentHash`] (and corresponding [`PaymentPreimage`]) must be globally unique. This
        /// method may return an Err if another payment with the same payment_hash is still pending.
        ///
-       /// `user_payment_id` will be provided back in [`PaymentPurpose::InvoicePayment::user_payment_id`] events to
-       /// allow tracking of which events correspond with which calls to this and
-       /// [`create_inbound_payment`]. `user_payment_id` has no meaning inside of LDK, it is simply
-       /// copied to events and otherwise ignored. It may be used to correlate PaymentReceived events
-       /// with invoice metadata stored elsewhere.
-       ///
        /// `min_value_msat` should be set if the invoice being generated contains a value. Any payment
        /// received for the returned [`PaymentHash`] will be required to be at least `min_value_msat`
        /// before a [`PaymentReceived`] event will be generated, ensuring that we do not provide the
@@ -4618,9 +4615,8 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///
        /// [`create_inbound_payment`]: Self::create_inbound_payment
        /// [`PaymentReceived`]: events::Event::PaymentReceived
-       /// [`PaymentPurpose::InvoicePayment::user_payment_id`]: events::PaymentPurpose::InvoicePayment::user_payment_id
-       pub fn create_inbound_payment_for_hash(&self, payment_hash: PaymentHash, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32, user_payment_id: u64) -> Result<PaymentSecret, APIError> {
-               self.set_payment_hash_secret_map(payment_hash, None, min_value_msat, invoice_expiry_delta_secs, user_payment_id)
+       pub fn create_inbound_payment_for_hash(&self, payment_hash: PaymentHash, min_value_msat: Option<u64>, invoice_expiry_delta_secs: u32) -> Result<PaymentSecret, APIError> {
+               self.set_payment_hash_secret_map(payment_hash, None, min_value_msat, invoice_expiry_delta_secs)
        }
 
        #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
@@ -6680,7 +6676,7 @@ pub mod bench {
                                payment_preimage.0[0..8].copy_from_slice(&payment_count.to_le_bytes());
                                payment_count += 1;
                                let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
-                               let payment_secret = $node_b.create_inbound_payment_for_hash(payment_hash, None, 7200, 0).unwrap();
+                               let payment_secret = $node_b.create_inbound_payment_for_hash(payment_hash, None, 7200).unwrap();
 
                                $node_a.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
                                let payment_event = SendEvent::from_event($node_a.get_and_clear_pending_msg_events().pop().unwrap());
index e9e36e607ec45950dc4ebadab6a8c940c756f114..08681964821f07a6caa65cfc39e620a08070366e 100644 (file)
@@ -999,7 +999,7 @@ macro_rules! get_payment_preimage_hash {
                        let payment_preimage = PaymentPreimage([*payment_count; 32]);
                        *payment_count += 1;
                        let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
-                       let payment_secret = $dest_node.node.create_inbound_payment_for_hash(payment_hash, $min_value_msat, 7200, 0).unwrap();
+                       let payment_secret = $dest_node.node.create_inbound_payment_for_hash(payment_hash, $min_value_msat, 7200).unwrap();
                        (payment_preimage, payment_hash, payment_secret)
                }
        }
index 8e9893870dadf8c128b2025b6b2142443df7505c..2ae12c39ec75f89fff610a17e9387098941c84c5 100644 (file)
@@ -1152,7 +1152,7 @@ fn test_duplicate_htlc_different_direction_onchain() {
        let (payment_preimage, payment_hash, _) = route_payment(&nodes[0], &vec!(&nodes[1])[..], 900_000);
 
        let (route, _, _, _) = get_route_and_payment_hash!(nodes[1], nodes[0], 800_000);
-       let node_a_payment_secret = nodes[0].node.create_inbound_payment_for_hash(payment_hash, None, 7200, 0).unwrap();
+       let node_a_payment_secret = nodes[0].node.create_inbound_payment_for_hash(payment_hash, None, 7200).unwrap();
        send_along_route_with_secret(&nodes[1], route, &[&[&nodes[0]]], 800_000, payment_hash, node_a_payment_secret);
 
        // Provide preimage to node 0 by claiming payment
@@ -4957,7 +4957,7 @@ fn test_duplicate_payment_hash_one_failure_one_success() {
 
        let (our_payment_preimage, duplicate_payment_hash, _) = route_payment(&nodes[0], &vec!(&nodes[1], &nodes[2])[..], 900000);
 
-       let payment_secret = nodes[3].node.create_inbound_payment_for_hash(duplicate_payment_hash, None, 7200, 0).unwrap();
+       let payment_secret = nodes[3].node.create_inbound_payment_for_hash(duplicate_payment_hash, None, 7200).unwrap();
        // We reduce the final CLTV here by a somewhat arbitrary constant to keep it under the one-byte
        // script push size limit so that the below script length checks match
        // ACCEPTED_HTLC_SCRIPT_WEIGHT.
@@ -5160,30 +5160,30 @@ fn do_test_fail_backwards_unrevoked_remote_announce(deliver_last_raa: bool, anno
        let (_, payment_hash_2, _) = route_payment(&nodes[0], &[&nodes[2], &nodes[3], &nodes[4]], ds_dust_limit*1000); // not added < dust limit + HTLC tx fee
        let (route, _, _, _) = get_route_and_payment_hash!(nodes[1], nodes[5], ds_dust_limit*1000);
        // 2nd HTLC:
-       send_along_route_with_secret(&nodes[1], route.clone(), &[&[&nodes[2], &nodes[3], &nodes[5]]], ds_dust_limit*1000, payment_hash_1, nodes[5].node.create_inbound_payment_for_hash(payment_hash_1, None, 7200, 0).unwrap()); // not added < dust limit + HTLC tx fee
+       send_along_route_with_secret(&nodes[1], route.clone(), &[&[&nodes[2], &nodes[3], &nodes[5]]], ds_dust_limit*1000, payment_hash_1, nodes[5].node.create_inbound_payment_for_hash(payment_hash_1, None, 7200).unwrap()); // not added < dust limit + HTLC tx fee
        // 3rd HTLC:
-       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], ds_dust_limit*1000, payment_hash_2, nodes[5].node.create_inbound_payment_for_hash(payment_hash_2, None, 7200, 0).unwrap()); // not added < dust limit + HTLC tx fee
+       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], ds_dust_limit*1000, payment_hash_2, nodes[5].node.create_inbound_payment_for_hash(payment_hash_2, None, 7200).unwrap()); // not added < dust limit + HTLC tx fee
        // 4th HTLC:
        let (_, payment_hash_3, _) = route_payment(&nodes[0], &[&nodes[2], &nodes[3], &nodes[4]], 1000000);
        // 5th HTLC:
        let (_, payment_hash_4, _) = route_payment(&nodes[0], &[&nodes[2], &nodes[3], &nodes[4]], 1000000);
        let (route, _, _, _) = get_route_and_payment_hash!(nodes[1], nodes[5], 1000000);
        // 6th HTLC:
-       send_along_route_with_secret(&nodes[1], route.clone(), &[&[&nodes[2], &nodes[3], &nodes[5]]], 1000000, payment_hash_3, nodes[5].node.create_inbound_payment_for_hash(payment_hash_3, None, 7200, 0).unwrap());
+       send_along_route_with_secret(&nodes[1], route.clone(), &[&[&nodes[2], &nodes[3], &nodes[5]]], 1000000, payment_hash_3, nodes[5].node.create_inbound_payment_for_hash(payment_hash_3, None, 7200).unwrap());
        // 7th HTLC:
-       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], 1000000, payment_hash_4, nodes[5].node.create_inbound_payment_for_hash(payment_hash_4, None, 7200, 0).unwrap());
+       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], 1000000, payment_hash_4, nodes[5].node.create_inbound_payment_for_hash(payment_hash_4, None, 7200).unwrap());
 
        // 8th HTLC:
        let (_, payment_hash_5, _) = route_payment(&nodes[0], &[&nodes[2], &nodes[3], &nodes[4]], 1000000);
        // 9th HTLC:
        let (route, _, _, _) = get_route_and_payment_hash!(nodes[1], nodes[5], ds_dust_limit*1000);
-       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], ds_dust_limit*1000, payment_hash_5, nodes[5].node.create_inbound_payment_for_hash(payment_hash_5, None, 7200, 0).unwrap()); // not added < dust limit + HTLC tx fee
+       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], ds_dust_limit*1000, payment_hash_5, nodes[5].node.create_inbound_payment_for_hash(payment_hash_5, None, 7200).unwrap()); // not added < dust limit + HTLC tx fee
 
        // 10th HTLC:
        let (_, payment_hash_6, _) = route_payment(&nodes[0], &[&nodes[2], &nodes[3], &nodes[4]], ds_dust_limit*1000); // not added < dust limit + HTLC tx fee
        // 11th HTLC:
        let (route, _, _, _) = get_route_and_payment_hash!(nodes[1], nodes[5], 1000000);
-       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], 1000000, payment_hash_6, nodes[5].node.create_inbound_payment_for_hash(payment_hash_6, None, 7200, 0).unwrap());
+       send_along_route_with_secret(&nodes[1], route, &[&[&nodes[2], &nodes[3], &nodes[5]]], 1000000, payment_hash_6, nodes[5].node.create_inbound_payment_for_hash(payment_hash_6, None, 7200).unwrap());
 
        // Double-check that six of the new HTLC were added
        // We now have six HTLCs pending over the dust limit and six HTLCs under the dust limit (ie,
@@ -7164,7 +7164,7 @@ fn test_check_htlc_underpaying() {
        let payee = Payee::from_node_id(nodes[1].node.get_our_node_id()).with_features(InvoiceFeatures::known());
        let route = get_route(&nodes[0].node.get_our_node_id(), &payee, nodes[0].network_graph, None, 10_000, TEST_FINAL_CLTV, nodes[0].logger, &scorer).unwrap();
        let (_, our_payment_hash, _) = get_payment_preimage_hash!(nodes[0]);
-       let our_payment_secret = nodes[1].node.create_inbound_payment_for_hash(our_payment_hash, Some(100_000), 7200, 0).unwrap();
+       let our_payment_secret = nodes[1].node.create_inbound_payment_for_hash(our_payment_hash, Some(100_000), 7200).unwrap();
        nodes[0].node.send_payment(&route, our_payment_hash, &Some(our_payment_secret)).unwrap();
        check_added_monitors!(nodes[0], 1);
 
@@ -8018,7 +8018,7 @@ fn test_preimage_storage() {
        create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 
        {
-               let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(100_000), 7200, 42);
+               let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(100_000), 7200);
                let (route, _, _, _) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
                nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
                check_added_monitors!(nodes[0], 1);
@@ -8035,8 +8035,7 @@ fn test_preimage_storage() {
        match events[0] {
                Event::PaymentReceived { ref purpose, .. } => {
                        match &purpose {
-                               PaymentPurpose::InvoicePayment { payment_preimage, user_payment_id, .. } => {
-                                       assert_eq!(*user_payment_id, 42);
+                               PaymentPurpose::InvoicePayment { payment_preimage, .. } => {
                                        claim_payment(&nodes[0], &[&nodes[1]], payment_preimage.unwrap());
                                },
                                _ => panic!("expected PaymentPurpose::InvoicePayment")
@@ -8056,11 +8055,11 @@ fn test_secret_timeout() {
 
        create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 
-       let (payment_hash, payment_secret_1) = nodes[1].node.create_inbound_payment(Some(100_000), 2, 0);
+       let (payment_hash, payment_secret_1) = nodes[1].node.create_inbound_payment(Some(100_000), 2);
 
        // We should fail to register the same payment hash twice, at least until we've connected a
        // block with time 7200 + CHAN_CONFIRM_DEPTH + 1.
-       if let Err(APIError::APIMisuseError { err }) = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(100_000), 2, 0) {
+       if let Err(APIError::APIMisuseError { err }) = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(100_000), 2) {
                assert_eq!(err, "Duplicate payment hash");
        } else { panic!(); }
        let mut block = {
@@ -8075,16 +8074,16 @@ fn test_secret_timeout() {
                }
        };
        connect_block(&nodes[1], &block);
-       if let Err(APIError::APIMisuseError { err }) = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(100_000), 2, 0) {
+       if let Err(APIError::APIMisuseError { err }) = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(100_000), 2) {
                assert_eq!(err, "Duplicate payment hash");
        } else { panic!(); }
 
        // If we then connect the second block, we should be able to register the same payment hash
-       // again with a different user_payment_id (this time getting a new payment secret).
+       // again (this time getting a new payment secret).
        block.header.prev_blockhash = block.header.block_hash();
        block.header.time += 1;
        connect_block(&nodes[1], &block);
-       let our_payment_secret = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(100_000), 2, 42).unwrap();
+       let our_payment_secret = nodes[1].node.create_inbound_payment_for_hash(payment_hash, Some(100_000), 2).unwrap();
        assert_ne!(payment_secret_1, our_payment_secret);
 
        {
@@ -8102,9 +8101,8 @@ fn test_secret_timeout() {
        let events = nodes[1].node.get_and_clear_pending_events();
        assert_eq!(events.len(), 1);
        match events[0] {
-               Event::PaymentReceived { purpose: PaymentPurpose::InvoicePayment { payment_preimage, payment_secret, user_payment_id }, .. } => {
+               Event::PaymentReceived { purpose: PaymentPurpose::InvoicePayment { payment_preimage, payment_secret }, .. } => {
                        assert!(payment_preimage.is_none());
-                       assert_eq!(user_payment_id, 42);
                        assert_eq!(payment_secret, our_payment_secret);
                        // We don't actually have the payment preimage with which to claim this payment!
                },
@@ -8124,7 +8122,7 @@ fn test_bad_secret_hash() {
 
        let random_payment_hash = PaymentHash([42; 32]);
        let random_payment_secret = PaymentSecret([43; 32]);
-       let (our_payment_hash, our_payment_secret) = nodes[1].node.create_inbound_payment(Some(100_000), 2, 0);
+       let (our_payment_hash, our_payment_secret) = nodes[1].node.create_inbound_payment(Some(100_000), 2);
        let (route, _, _, _) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
 
        // All the below cases should end up being handled exactly identically, so we macro the
index 6bbd6b9946ccc49e18ae7b85a715b23d2478f4ad..29d294c5cbd11066391eb5950655226ae2dd97e0 100644 (file)
@@ -60,15 +60,6 @@ pub enum PaymentPurpose {
                /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
                /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
                payment_secret: PaymentSecret,
-               /// This is the `user_payment_id` which was provided to
-               /// [`ChannelManager::create_inbound_payment_for_hash`] or
-               /// [`ChannelManager::create_inbound_payment`]. It has no meaning inside of LDK and is
-               /// simply copied here. It may be used to correlate PaymentReceived events with invoice
-               /// metadata stored elsewhere.
-               ///
-               /// [`ChannelManager::create_inbound_payment`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment
-               /// [`ChannelManager::create_inbound_payment_for_hash`]: crate::ln::channelmanager::ChannelManager::create_inbound_payment_for_hash
-               user_payment_id: u64,
        },
        /// Because this is a spontaneous payment, the payer generated their own preimage rather than us
        /// (the payee) providing a preimage.
@@ -352,13 +343,11 @@ impl Writeable for Event {
                        &Event::PaymentReceived { ref payment_hash, ref amt, ref purpose } => {
                                1u8.write(writer)?;
                                let mut payment_secret = None;
-                               let mut user_payment_id = None;
                                let payment_preimage;
                                match &purpose {
-                                       PaymentPurpose::InvoicePayment { payment_preimage: preimage, payment_secret: secret, user_payment_id: id } => {
+                                       PaymentPurpose::InvoicePayment { payment_preimage: preimage, payment_secret: secret } => {
                                                payment_secret = Some(secret);
                                                payment_preimage = *preimage;
-                                               user_payment_id = Some(id);
                                        },
                                        PaymentPurpose::SpontaneousPayment(preimage) => {
                                                payment_preimage = Some(*preimage);
@@ -368,7 +357,7 @@ impl Writeable for Event {
                                        (0, payment_hash, required),
                                        (2, payment_secret, option),
                                        (4, amt, required),
-                                       (6, user_payment_id, option),
+                                       (6, 0u64, required), // user_payment_id required for compatibility with 0.0.103 and earlier
                                        (8, payment_preimage, option),
                                });
                        },
@@ -457,21 +446,18 @@ impl MaybeReadable for Event {
                                        let mut payment_preimage = None;
                                        let mut payment_secret = None;
                                        let mut amt = 0;
-                                       let mut user_payment_id = None;
+                                       let mut _user_payment_id = None; // For compatibility with 0.0.103 and earlier
                                        read_tlv_fields!(reader, {
                                                (0, payment_hash, required),
                                                (2, payment_secret, option),
                                                (4, amt, required),
-                                               (6, user_payment_id, option),
+                                               (6, _user_payment_id, option),
                                                (8, payment_preimage, option),
                                        });
                                        let purpose = match payment_secret {
                                                Some(secret) => PaymentPurpose::InvoicePayment {
                                                        payment_preimage,
-                                                       payment_secret: secret,
-                                                       user_payment_id: if let Some(id) = user_payment_id {
-                                                               id
-                                                       } else { return Err(msgs::DecodeError::InvalidValue) }
+                                                       payment_secret: secret
                                                },
                                                None if payment_preimage.is_some() => PaymentPurpose::SpontaneousPayment(payment_preimage.unwrap()),
                                                None => return Err(msgs::DecodeError::InvalidValue),