Merge pull request #1057 from TheBlueMatt/2021-08-invoice-fails
[rust-lightning] / lightning-invoice / src / lib.rs
index 2ce58f296f9b26b06ec4c92d8b634a57f680d5b3..61e394da6dba4ef70979a5dae1d673ce2b483732 100644 (file)
@@ -127,6 +127,7 @@ pub fn check_platform() {
 ///
 /// ```
 /// extern crate secp256k1;
+/// extern crate lightning;
 /// extern crate lightning_invoice;
 /// extern crate bitcoin_hashes;
 ///
@@ -136,6 +137,8 @@ pub fn check_platform() {
 /// use secp256k1::Secp256k1;
 /// use secp256k1::key::SecretKey;
 ///
+/// use lightning::ln::PaymentSecret;
+///
 /// use lightning_invoice::{Currency, InvoiceBuilder};
 ///
 /// # fn main() {
@@ -148,10 +151,12 @@ pub fn check_platform() {
 ///    ).unwrap();
 ///
 /// let payment_hash = sha256::Hash::from_slice(&[0; 32][..]).unwrap();
+/// let payment_secret = PaymentSecret([42u8; 32]);
 ///
 /// let invoice = InvoiceBuilder::new(Currency::Bitcoin)
 ///    .description("Coins pls!".into())
 ///    .payment_hash(payment_hash)
+///    .payment_secret(payment_secret)
 ///    .current_timestamp()
 ///    .min_final_cltv_expiry(144)
 ///    .build_signed(|hash| {
@@ -321,7 +326,7 @@ impl SiPrefix {
 }
 
 /// Enum representing the crypto currencies (or networks) supported by this library
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub enum Currency {
        /// Bitcoin mainnet
        Bitcoin,
@@ -342,7 +347,7 @@ pub enum Currency {
 /// Tagged field which may have an unknown tag
 ///
 /// (C-not exported) as we don't currently support TaggedField
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub enum RawTaggedField {
        /// Parsed tagged field with known tag
        KnownSemantics(TaggedField),
@@ -357,7 +362,7 @@ pub enum RawTaggedField {
 /// (C-not exported) As we don't yet support enum variants with the same name the struct contained
 /// in the variant.
 #[allow(missing_docs)]
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub enum TaggedField {
        PaymentHash(Sha256),
        Description(Description),
@@ -372,18 +377,18 @@ pub enum TaggedField {
 }
 
 /// SHA-256 hash
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub struct Sha256(pub sha256::Hash);
 
 /// Description string
 ///
 /// # Invariants
 /// The description can be at most 639 __bytes__ long
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub struct Description(String);
 
 /// Payee public key
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub struct PayeePubKey(pub PublicKey);
 
 /// Positive duration that defines when (relatively to the timestamp) in the future the invoice
@@ -393,17 +398,17 @@ pub struct PayeePubKey(pub PublicKey);
 /// The number of seconds this expiry time represents has to be in the range
 /// `0...(SYSTEM_TIME_MAX_UNIX_TIMESTAMP - MAX_EXPIRY_TIME)` to avoid overflows when adding it to a
 /// timestamp
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub struct ExpiryTime(Duration);
 
 /// `min_final_cltv_expiry` to use for the last HTLC in the route
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub struct MinFinalCltvExpiry(pub u64);
 
 // TODO: better types instead onf byte arrays
 /// Fallback address in case no LN payment is possible
 #[allow(missing_docs)]
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub enum Fallback {
        SegWitProgram {
                version: u5,
@@ -414,7 +419,7 @@ pub enum Fallback {
 }
 
 /// Recoverable signature
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Eq, PartialEq)]
 pub struct InvoiceSignature(pub RecoverableSignature);
 
 /// Private routing information
@@ -422,7 +427,7 @@ pub struct InvoiceSignature(pub RecoverableSignature);
 /// # Invariants
 /// The encoded route has to be <1024 5bit characters long (<=639 bytes or <=12 hops)
 ///
-#[derive(Eq, PartialEq, Debug, Clone)]
+#[derive(Clone, Debug, Hash, Eq, PartialEq)]
 pub struct PrivateRoute(RouteHint);
 
 /// Tag constants as specified in BOLT11
@@ -480,8 +485,9 @@ impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool, S: tb::Bool> InvoiceBui
                }
        }
 
-       /// Sets the amount in pico BTC. The optimal SI prefix is choosen automatically.
-       pub fn amount_pico_btc(mut self, amount: u64) -> Self {
+       /// Sets the amount in millisatoshis. The optimal SI prefix is chosen automatically.
+       pub fn amount_milli_satoshis(mut self, amount_msat: u64) -> Self {
+               let amount = amount_msat * 10; // Invoices are denominated in "pico BTC"
                let biggest_possible_si_prefix = SiPrefix::values_desc()
                        .iter()
                        .find(|prefix| amount % prefix.multiplier() == 0)
@@ -633,7 +639,7 @@ impl<D: tb::Bool, H: tb::Bool, T: tb::Bool, C: tb::Bool> InvoiceBuilder<D, H, T,
        }
 }
 
-impl<S: tb::Bool> InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, S> {
+impl InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, tb::True> {
        /// Builds and signs an invoice using the supplied `sign_function`. This function MAY NOT fail
        /// and MUST produce a recoverable signature valid for the given hash and if applicable also for
        /// the included payee public key.
@@ -673,6 +679,7 @@ impl<S: tb::Bool> InvoiceBuilder<tb::True, tb::True, tb::True, tb::True, S> {
 
                invoice.check_field_counts().expect("should be ensured by type signature of builder");
                invoice.check_feature_bits().expect("should be ensured by type signature of builder");
+               invoice.check_amount().expect("should be ensured by type signature of builder");
 
                Ok(invoice)
        }
@@ -1016,35 +1023,54 @@ impl Invoice {
                        return  Err(SemanticError::MultipleDescriptions);
                }
 
+               self.check_payment_secret()?;
+
                Ok(())
        }
 
-       /// Check that feature bits are set as required
-       fn check_feature_bits(&self) -> Result<(), SemanticError> {
-               // "If the payment_secret feature is set, MUST include exactly one s field."
+       /// Checks that there is exactly one payment secret field
+       fn check_payment_secret(&self) -> Result<(), SemanticError> {
+               // "A writer MUST include exactly one `s` field."
                let payment_secret_count = self.tagged_fields().filter(|&tf| match *tf {
                        TaggedField::PaymentSecret(_) => true,
                        _ => false,
                }).count();
-               if payment_secret_count > 1 {
+               if payment_secret_count < 1 {
+                       return Err(SemanticError::NoPaymentSecret);
+               } else if payment_secret_count > 1 {
                        return Err(SemanticError::MultiplePaymentSecrets);
                }
 
+               Ok(())
+       }
+
+       /// Check that amount is a whole number of millisatoshis
+       fn check_amount(&self) -> Result<(), SemanticError> {
+               if let Some(amount_pico_btc) = self.amount_pico_btc() {
+                       if amount_pico_btc % 10 != 0 {
+                               return Err(SemanticError::ImpreciseAmount);
+                       }
+               }
+               Ok(())
+       }
+
+       /// Check that feature bits are set as required
+       fn check_feature_bits(&self) -> Result<(), SemanticError> {
+               self.check_payment_secret()?;
+
                // "A writer MUST set an s field if and only if the payment_secret feature is set."
-               let has_payment_secret = payment_secret_count == 1;
+               // (this requirement has been since removed, and we now require the payment secret
+               // feature bit always).
                let features = self.tagged_fields().find(|&tf| match *tf {
                        TaggedField::Features(_) => true,
                        _ => false,
                });
                match features {
-                       None if has_payment_secret => Err(SemanticError::InvalidFeatures),
-                       None => Ok(()),
+                       None => Err(SemanticError::InvalidFeatures),
                        Some(TaggedField::Features(features)) => {
-                               if features.supports_payment_secret() && has_payment_secret {
-                                       Ok(())
-                               } else if has_payment_secret {
+                               if features.requires_unknown_bits() {
                                        Err(SemanticError::InvalidFeatures)
-                               } else if features.supports_payment_secret() {
+                               } else if !features.supports_payment_secret() {
                                        Err(SemanticError::InvalidFeatures)
                                } else {
                                        Ok(())
@@ -1059,7 +1085,9 @@ impl Invoice {
                match self.signed_invoice.recover_payee_pub_key() {
                        Err(secp256k1::Error::InvalidRecoveryId) =>
                                return Err(SemanticError::InvalidRecoveryId),
-                       Err(_) => panic!("no other error may occur"),
+                       Err(secp256k1::Error::InvalidSignature) =>
+                               return Err(SemanticError::InvalidSignature),
+                       Err(e) => panic!("no other error may occur, got {:?}", e),
                        Ok(_) => {},
                }
 
@@ -1074,10 +1102,17 @@ impl Invoice {
        /// ```
        /// use lightning_invoice::*;
        ///
-       /// let invoice = "lnbc1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdp\
-       ///     l2pkx2ctnv5sxxmmwwd5kgetjypeh2ursdae8g6twvus8g6rfwvs8qun0dfjkxaq8rkx3yf5tcsyz3d7\
-       ///     3gafnh3cax9rn449d9p5uxz9ezhhypd0elx87sjle52x86fux2ypatgddc6k63n7erqz25le42c4u4ec\
-       ///     ky03ylcqca784w";
+       /// let invoice = "lnbc100p1psj9jhxdqud3jxktt5w46x7unfv9kz6mn0v3jsnp4q0d3p2sfluzdx45tqcs\
+       /// h2pu5qc7lgq0xs578ngs6s0s68ua4h7cvspp5q6rmq35js88zp5dvwrv9m459tnk2zunwj5jalqtyxqulh0l\
+       /// 5gflssp5nf55ny5gcrfl30xuhzj3nphgj27rstekmr9fw3ny5989s300gyus9qyysgqcqpcrzjqw2sxwe993\
+       /// h5pcm4dxzpvttgza8zhkqxpgffcrf5v25nwpr3cmfg7z54kuqq8rgqqqqqqqq2qqqqq9qq9qrzjqd0ylaqcl\
+       /// j9424x9m8h2vcukcgnm6s56xfgu3j78zyqzhgs4hlpzvznlugqq9vsqqqqqqqlgqqqqqeqq9qrzjqwldmj9d\
+       /// ha74df76zhx6l9we0vjdquygcdt3kssupehe64g6yyp5yz5rhuqqwccqqyqqqqlgqqqqjcqq9qrzjqf9e58a\
+       /// guqr0rcun0ajlvmzq3ek63cw2w282gv3z5uupmuwvgjtq2z55qsqqg6qqqyqqqrtnqqqzq3cqygrzjqvphms\
+       /// ywntrrhqjcraumvc4y6r8v4z5v593trte429v4hredj7ms5z52usqq9ngqqqqqqqlgqqqqqqgq9qrzjq2v0v\
+       /// p62g49p7569ev48cmulecsxe59lvaw3wlxm7r982zxa9zzj7z5l0cqqxusqqyqqqqlgqqqqqzsqygarl9fh3\
+       /// 8s0gyuxjjgux34w75dnc6xp2l35j7es3jd4ugt3lu0xzre26yg5m7ke54n2d5sym4xcmxtl8238xxvw5h5h5\
+       /// j5r6drg6k6zcqj0fcwg";
        ///
        /// let signed = invoice.parse::<SignedRawInvoice>().unwrap();
        ///
@@ -1090,6 +1125,7 @@ impl Invoice {
                invoice.check_field_counts()?;
                invoice.check_feature_bits()?;
                invoice.check_signature()?;
+               invoice.check_amount()?;
 
                Ok(invoice)
        }
@@ -1130,8 +1166,8 @@ impl Invoice {
        }
 
        /// Get the payment secret if one was included in the invoice
-       pub fn payment_secret(&self) -> Option<&PaymentSecret> {
-               self.signed_invoice.payment_secret()
+       pub fn payment_secret(&self) -> &PaymentSecret {
+               self.signed_invoice.payment_secret().expect("was checked by constructor")
        }
 
        /// Get the invoice features if they were included in the invoice
@@ -1388,6 +1424,10 @@ pub enum SemanticError {
        /// The invoice contains multiple descriptions and/or description hashes which isn't allowed
        MultipleDescriptions,
 
+       /// The invoice is missing the mandatory payment secret, which all modern lightning nodes
+       /// should provide.
+       NoPaymentSecret,
+
        /// The invoice contains multiple payment secrets
        MultiplePaymentSecrets,
 
@@ -1399,6 +1439,9 @@ pub enum SemanticError {
 
        /// The invoice's signature is invalid
        InvalidSignature,
+
+       /// The invoice's amount was not a whole number of millisatoshis
+       ImpreciseAmount,
 }
 
 impl Display for SemanticError {
@@ -1408,10 +1451,12 @@ impl Display for SemanticError {
                        SemanticError::MultiplePaymentHashes => f.write_str("The invoice has multiple payment hashes which isn't allowed"),
                        SemanticError::NoDescription => f.write_str("No description or description hash are part of the invoice"),
                        SemanticError::MultipleDescriptions => f.write_str("The invoice contains multiple descriptions and/or description hashes which isn't allowed"),
+                       SemanticError::NoPaymentSecret => f.write_str("The invoice is missing the mandatory payment secret"),
                        SemanticError::MultiplePaymentSecrets => f.write_str("The invoice contains multiple payment secrets"),
                        SemanticError::InvalidFeatures => f.write_str("The invoice's features are invalid"),
                        SemanticError::InvalidRecoveryId => f.write_str("The recovery id doesn't fit the signature/pub key"),
                        SemanticError::InvalidSignature => f.write_str("The invoice's signature is invalid"),
+                       SemanticError::ImpreciseAmount => f.write_str("The invoice's amount was not a whole number of millisatoshis"),
                }
        }
 }
@@ -1623,7 +1668,7 @@ mod test {
                        let invoice = invoice_template.clone();
                        invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
                }.unwrap();
-               assert!(Invoice::from_signed(invoice).is_ok());
+               assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
 
                // No payment secret or feature bits
                let invoice = {
@@ -1631,7 +1676,7 @@ mod test {
                        invoice.data.tagged_fields.push(Features(InvoiceFeatures::empty()).into());
                        invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
                }.unwrap();
-               assert!(Invoice::from_signed(invoice).is_ok());
+               assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
 
                // Missing payment secret
                let invoice = {
@@ -1639,7 +1684,7 @@ mod test {
                        invoice.data.tagged_fields.push(Features(InvoiceFeatures::known()).into());
                        invoice.sign::<_, ()>(|hash| Ok(Secp256k1::new().sign_recoverable(hash, &private_key)))
                }.unwrap();
-               assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::InvalidFeatures));
+               assert_eq!(Invoice::from_signed(invoice), Err(SemanticError::NoPaymentSecret));
 
                // Multiple payment secrets
                let invoice = {
@@ -1661,7 +1706,7 @@ mod test {
                        .current_timestamp();
 
                let invoice = builder.clone()
-                       .amount_pico_btc(15000)
+                       .amount_milli_satoshis(1500)
                        .build_raw()
                        .unwrap();
 
@@ -1670,7 +1715,7 @@ mod test {
 
 
                let invoice = builder.clone()
-                       .amount_pico_btc(1500)
+                       .amount_milli_satoshis(150)
                        .build_raw()
                        .unwrap();
 
@@ -1725,6 +1770,7 @@ mod test {
 
                let sign_error_res = builder.clone()
                        .description("Test".into())
+                       .payment_secret(PaymentSecret([0; 32]))
                        .try_build_signed(|_| {
                                Err("ImaginaryError")
                        });
@@ -1801,7 +1847,7 @@ mod test {
                ]);
 
                let builder = InvoiceBuilder::new(Currency::BitcoinTestnet)
-                       .amount_pico_btc(123)
+                       .amount_milli_satoshis(123)
                        .timestamp(UNIX_EPOCH + Duration::from_secs(1234567))
                        .payee_pub_key(public_key.clone())
                        .expiry_time(Duration::from_secs(54321))
@@ -1821,7 +1867,7 @@ mod test {
                assert!(invoice.check_signature().is_ok());
                assert_eq!(invoice.tagged_fields().count(), 10);
 
-               assert_eq!(invoice.amount_pico_btc(), Some(123));
+               assert_eq!(invoice.amount_pico_btc(), Some(1230));
                assert_eq!(invoice.currency(), Currency::BitcoinTestnet);
                assert_eq!(
                        invoice.timestamp().duration_since(UNIX_EPOCH).unwrap().as_secs(),
@@ -1837,7 +1883,7 @@ mod test {
                        InvoiceDescription::Hash(&Sha256(sha256::Hash::from_slice(&[3;32][..]).unwrap()))
                );
                assert_eq!(invoice.payment_hash(), &sha256::Hash::from_slice(&[21;32][..]).unwrap());
-               assert_eq!(invoice.payment_secret(), Some(&PaymentSecret([42; 32])));
+               assert_eq!(invoice.payment_secret(), &PaymentSecret([42; 32]));
                assert_eq!(invoice.features(), Some(&InvoiceFeatures::known()));
 
                let raw_invoice = builder.build_raw().unwrap();
@@ -1853,6 +1899,7 @@ mod test {
                let signed_invoice = InvoiceBuilder::new(Currency::Bitcoin)
                        .description("Test".into())
                        .payment_hash(sha256::Hash::from_slice(&[0;32][..]).unwrap())
+                       .payment_secret(PaymentSecret([0; 32]))
                        .current_timestamp()
                        .build_raw()
                        .unwrap()