Implement bundle burn validation and serialization

Cargo.toml

@@ -23,4 +23,4 @@ zcash_encoding = { path = "components/zcash_encoding" }
 zcash_note_encryption = { path = "components/zcash_note_encryption" }
 schemer = { git = "https://github.com/aschampion/schemer.git", rev = "6726b60f43f72c6e24a18d31be0ec7d42829e5e1" }
 schemer-rusqlite = { git = "https://github.com/aschampion/schemer.git", rev = "6726b60f43f72c6e24a18d31be0ec7d42829e5e1" }
-orchard = { version = "0.3", git = "https://github.com/QED-it/orchard", rev = "35da288c7867c5b0fb0ae84e444915689e49084c" }
+orchard = { version = "0.3", git = "https://github.com/QED-it/orchard", rev = "65c9f1817c55e05319dc8e0e118f647f29ffd178" }

zcash_history/Cargo.toml

@@ -14,6 +14,10 @@ assert_matches = "1.3.0"
 quickcheck = "0.9"
 
 [dependencies]
+# TODO: Pined until we move to rust v1.64.0 or above to support winnow > 0.4.1
+winnow = "=0.4.1"
+# TODO: Pined until we move to rust v1.64.0 or above to support toml_datetime > 0.6.1
+toml_datetime = "=0.6.1"
 primitive-types = "0.11"
 byteorder = "1"
 blake2 = { package = "blake2b_simd", version = "1" }

zcash_primitives/src/transaction/components/orchard.rs

@@ -16,6 +16,11 @@ use zcash_encoding::{Array, CompactSize, Vector};
 use super::Amount;
 use crate::transaction::Transaction;
 
+mod burn_serialization;
+mod burn_validation;
+
+use burn_serialization::{read_bundle_burn, write_bundle_burn};
+
 pub const FLAG_SPENDS_ENABLED: u8 = 0b0000_0001;
 pub const FLAG_OUTPUTS_ENABLED: u8 = 0b0000_0010;
 pub const FLAGS_EXPECTED_UNSET: u8 = !(FLAG_SPENDS_ENABLED | FLAG_OUTPUTS_ENABLED);
@@ -44,6 +49,7 @@ pub fn read_v5_bundle<R: Read>(
     } else {
         let flags = read_flags(&mut reader)?;
         let value_balance = Transaction::read_amount(&mut reader)?;
+        let burn = read_bundle_burn(&mut reader)?;
         let anchor = read_anchor(&mut reader)?;
         let proof_bytes = Vector::read(&mut reader, |r| r.read_u8())?;
         let actions = NonEmpty::from_vec(
@@ -64,7 +70,7 @@ pub fn read_v5_bundle<R: Read>(
             actions,
             flags,
             value_balance,
-            vec![], // TODO implement "burn" reading and writing
+            burn,
             anchor,
             authorization,
         )))
@@ -194,6 +200,7 @@ pub fn write_v5_bundle<W: Write>(
 
         writer.write_all(&[bundle.flags().to_byte()])?;
         writer.write_all(&bundle.value_balance().to_i64_le_bytes())?;
+        write_bundle_burn(&mut writer, bundle.burn())?;
         writer.write_all(&bundle.anchor().to_bytes())?;
         Vector::write(
             &mut writer,

zcash_primitives/src/transaction/components/orchard/burn_serialization.rs

@@ -0,0 +1,114 @@
+use std::io::{self, Read, Write};
+
+use orchard::note::AssetBase;
+
+use zcash_encoding::Vector;
+
+use crate::transaction::Transaction;
+
+use super::{burn_validation::validate_bundle_burn, Amount};
+
+fn read_asset_base<R: Read>(mut reader: R) -> io::Result<AssetBase> {
+    let mut bytes = [0u8; 32];
+
+    reader.read_exact(&mut bytes)?;
+
+    Option::from(AssetBase::from_bytes(&bytes))
+        .ok_or_else(|| io::Error::new(io::ErrorKind::InvalidData, "Invalid AssetBase!"))
+}
+
+fn read_asset_burn<R: Read>(mut reader: R) -> io::Result<(AssetBase, Amount)> {
+    let asset_base = read_asset_base(&mut reader)?;
+    let amount = Transaction::read_amount(&mut reader)?;
+
+    Ok((asset_base, amount))
+}
+
+pub fn read_bundle_burn<R: Read>(mut reader: R) -> io::Result<Vec<(AssetBase, Amount)>> {
+    let burn = Vector::read(&mut reader, |r| read_asset_burn(r))?;
+    validate_bundle_burn(&burn)
+        .map_err(|err| io::Error::new(io::ErrorKind::InvalidData, err.to_string()))?;
+    Ok(burn)
+}
+
+fn write_amount<W: Write>(mut writer: W, amount: &Amount) -> io::Result<()> {
+    writer.write_all(&amount.to_i64_le_bytes())
+}
+
+fn write_asset_base<W: Write>(mut writer: W, asset_base: &AssetBase) -> io::Result<()> {
+    writer.write_all(&asset_base.to_bytes())
+}
+
+fn write_asset_burn<W: Write>(
+    mut writer: W,
+    (asset_base, amount): &(AssetBase, Amount),
+) -> io::Result<()> {
+    write_asset_base(&mut writer, asset_base)?;
+    write_amount(&mut writer, amount)?;
+
+    Ok(())
+}
+
+pub fn write_bundle_burn<W: Write>(
+    mut writer: W,
+    bundle_burn: &[(AssetBase, Amount)],
+) -> io::Result<()> {
+    Vector::write(&mut writer, bundle_burn, |w, b| write_asset_burn(w, b))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use std::io::Cursor;
+
+    use crate::transaction::tests::create_test_asset;
+
+    use super::super::burn_validation::BurnError;
+
+    #[test]
+    fn test_read_write_bundle_burn_success() {
+        let bundle_burn = (1..10)
+            .map(|i| {
+                (
+                    create_test_asset(&format!("Asset {i}")),
+                    Amount::from_u64(i * 10).unwrap(),
+                )
+            })
+            .collect::<Vec<_>>();
+
+        let mut buffer = Vec::new();
+        let mut cursor = Cursor::new(&mut buffer);
+        write_bundle_burn(&mut cursor, &bundle_burn).unwrap();
+
+        cursor.set_position(0);
+        let result = read_bundle_burn(&mut cursor).unwrap();
+
+        assert_eq!(result, bundle_burn);
+    }
+
+    // This test implementation covers only one failure case intentionally,
+    // as the other cases are already covered in the validate_bundle_burn tests.
+    #[test]
+    fn test_read_bundle_burn_duplicate_asset() {
+        let bundle_burn = vec![
+            (create_test_asset("Asset 1"), Amount::from_u64(10).unwrap()),
+            (create_test_asset("Asset 1"), Amount::from_u64(20).unwrap()),
+            (create_test_asset("Asset 3"), Amount::from_u64(10).unwrap()),
+        ];
+
+        let mut buffer = Vec::new();
+        let mut cursor = Cursor::new(&mut buffer);
+
+        write_bundle_burn(&mut cursor, &bundle_burn).unwrap();
+
+        cursor.set_position(0);
+
+        let result = read_bundle_burn(&mut cursor);
+
+        assert!(
+            matches!(result, Err(ref err) if err.kind() == io::ErrorKind::InvalidData &&
+              err.to_string() == BurnError::DuplicateAsset.to_string())
+        );
+    }
+}

zcash_primitives/src/transaction/components/orchard/burn_validation.rs

@@ -0,0 +1,118 @@
+use std::fmt;
+
+use orchard::note::AssetBase;
+
+use super::Amount;
+
+// FIXME: Consider making tuple (AssetBase, Amount) a new type.
+
+#[derive(Debug)]
+#[cfg_attr(test, derive(PartialEq))]
+pub enum BurnError {
+    DuplicateAsset,
+    NativeAsset,
+    ZeroAmount,
+}
+
+impl fmt::Display for BurnError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match *self {
+            BurnError::DuplicateAsset => write!(f, "Encountered a duplicate asset to burn."),
+            BurnError::NativeAsset => write!(f, "Cannot burn a native asset."),
+            BurnError::ZeroAmount => write!(f, "Cannot burn an asset with a zero amount."),
+        }
+    }
+}
+
+/// Validates burns for a bundle by ensuring each asset is unique, non-native, and has a non-zero value.
+///
+/// Each burn element is represented as a tuple of `AssetBase` and `Amount`, where `AssetBase` identifies
+/// the asset to be burned and `Amount` is the quantity to burn.
+///
+/// # Arguments
+///
+/// * `burns` - A vector of burns, where each burn is represented as a tuple of `AssetBase` and `Amount`.
+///
+/// # Errors
+///
+/// Returns a `BurnError` if:
+/// * Any asset in the list of burns is not unique (`BurnError::DuplicateAsset`).
+/// * Any asset in the list of burns is native (`BurnError::NativeAsset`).
+/// * Any asset in the list of burns has a zero amount (`BurnError::ZeroAmount`).
+pub fn validate_bundle_burn(bundle_burn: &Vec<(AssetBase, Amount)>) -> Result<(), BurnError> {
+    let mut asset_set = std::collections::HashSet::<AssetBase>::new();
+
+    for (asset, amount) in bundle_burn {
+        if !asset_set.insert(*asset) {
+            return Err(BurnError::DuplicateAsset);
+        }
+        if asset.is_native().into() {
+            return Err(BurnError::NativeAsset);
+        }
+        // FIXME: check for negative amounts?
+        if i64::from(amount) == 0 {
+            return Err(BurnError::ZeroAmount);
+        }
+    }
+
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use crate::transaction::tests::create_test_asset;
+
+    #[test]
+    fn test_validate_bundle_burn_success() {
+        let bundle_burn = vec![
+            (create_test_asset("Asset 1"), Amount::from_u64(10).unwrap()),
+            (create_test_asset("Asset 2"), Amount::from_u64(20).unwrap()),
+            (create_test_asset("Asset 3"), Amount::from_u64(10).unwrap()),
+        ];
+
+        let result = validate_bundle_burn(&bundle_burn);
+
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_validate_bundle_burn_duplicate_asset() {
+        let bundle_burn = vec![
+            (create_test_asset("Asset 1"), Amount::from_u64(10).unwrap()),
+            (create_test_asset("Asset 1"), Amount::from_u64(20).unwrap()),
+            (create_test_asset("Asset 3"), Amount::from_u64(10).unwrap()),
+        ];
+
+        let result = validate_bundle_burn(&bundle_burn);
+
+        assert_eq!(result, Err(BurnError::DuplicateAsset));
+    }
+
+    #[test]
+    fn test_validate_bundle_burn_native_asset() {
+        let bundle_burn = vec![
+            (create_test_asset("Asset 1"), Amount::from_u64(10).unwrap()),
+            (AssetBase::native(), Amount::from_u64(20).unwrap()),
+            (create_test_asset("Asset 3"), Amount::from_u64(10).unwrap()),
+        ];
+
+        let result = validate_bundle_burn(&bundle_burn);
+
+        assert_eq!(result, Err(BurnError::NativeAsset));
+    }
+
+    #[test]
+    fn test_validate_bundle_burn_zero_amount() {
+        let bundle_burn = vec![
+            (create_test_asset("Asset 1"), Amount::from_u64(10).unwrap()),
+            (create_test_asset("Asset 2"), Amount::from_u64(0).unwrap()),
+            (create_test_asset("Asset 3"), Amount::from_u64(10).unwrap()),
+        ];
+
+        let result = validate_bundle_burn(&bundle_burn);
+
+        assert_eq!(result, Err(BurnError::ZeroAmount));
+    }
+}

zcash_primitives/src/transaction/tests.rs

@@ -23,6 +23,18 @@ use super::{
 #[cfg(feature = "zfuture")]
 use super::components::tze;
 
+pub fn create_test_asset(asset_desc: &str) -> orchard::note::AssetBase {
+    use orchard::{
+        keys::{IssuanceAuthorizingKey, IssuanceValidatingKey, SpendingKey},
+        note::AssetBase,
+    };
+
+    let sk = SpendingKey::from_bytes([0u8; 32]).unwrap();
+    let isk: IssuanceAuthorizingKey = (&sk).into();
+
+    AssetBase::derive(&IssuanceValidatingKey::from(&isk), asset_desc)
+}
+
 #[test]
 fn tx_read_write() {
     let data = &self::data::tx_read_write::TX_READ_WRITE;