Implement handling of EphemeralAddresses

zcash_client_memory/Cargo.toml

@@ -60,6 +60,7 @@ async-trait = { version = "0.1" }
 # - Test dependencies
 proptest = { workspace = true, optional = true }
 wasm_sync = "0.1.2"
+time.workspace = true
 
 [dev-dependencies]
 ciborium = "0.2.2"

zcash_client_memory/src/error.rs

@@ -38,7 +38,8 @@ pub enum Error {
     Io(std::io::Error),
     #[error("Corrupted Data: {0}")]
     CorruptedData(String),
-    #[error("An error occurred while processing an account due to a failure in deriving the account's keys: {0}")]
+    #[error("An error occurred while processing an account due to a failure in deriving the account's keys: {0}"
+    )]
     BadAccountData(String),
     #[error("Blocks are non sequental")]
     NonSequentialBlocks,
@@ -65,10 +66,19 @@ pub enum Error {
     #[cfg(feature = "transparent-inputs")]
     #[error("Requested gap limit {1} reached for account {0:?}")]
     ReachedGapLimit(AccountId, u32),
+    #[cfg(feature = "transparent-inputs")]
+    #[error("Transparent derivation: {0}")]
+    TransparentDerivation(bip32::Error),
     #[error("Address Conversion error: {0}")]
     ConversionError(ConversionError<&'static str>),
 }
+#[cfg(feature = "transparent-inputs")]
 
+impl From<bip32::Error> for Error {
+    fn from(value: bip32::Error) -> Self {
+        Error::TransparentDerivation(value)
+    }
+}
 impl From<ConversionError<&'static str>> for Error {
     fn from(value: ConversionError<&'static str>) -> Self {
         Error::ConversionError(value)

zcash_client_memory/src/lib.rs

@@ -8,6 +8,7 @@ use shardtree::{
     store::{memory::MemoryShardStore, ShardStore as _},
     ShardTree,
 };
+use std::cmp::min;
 use std::{
     collections::{btree_map::Entry, BTreeMap, BTreeSet},
     num::NonZeroU32,
@@ -31,7 +32,7 @@ use zcash_primitives::{
     transaction::{components::OutPoint, TxId},
 };
 
-use zcash_client_backend::data_api::SAPLING_SHARD_HEIGHT;
+use zcash_client_backend::data_api::{GAP_LIMIT, SAPLING_SHARD_HEIGHT};
 use zcash_client_backend::{
     data_api::{
         scanning::{ScanPriority, ScanRange},
@@ -67,6 +68,7 @@ pub(crate) const PRUNING_DEPTH: u32 = 100;
 pub(crate) const VERIFY_LOOKAHEAD: u32 = 10;
 
 use types::serialization::*;
+use zcash_primitives::transaction::Transaction;
 
 /// The main in-memory wallet database. Implements all the traits needed to be used as a backend.
 #[serde_as]
@@ -232,6 +234,63 @@ impl<P: consensus::Parameters> MemoryWalletDb<P> {
         Ok((id, account))
     }
 
+    #[cfg(feature = "transparent-inputs")]
+    pub fn first_unsafe_index(&self, account_id: AccountId) -> Result<u32, Error> {
+        let first_unmined_index = if let Some(account) = self.accounts.get(account_id) {
+            let mut idx = 0;
+            for ((tidx, eph_addr)) in account.ephemeral_addresses.iter().rev() {
+                if let Some(_) = eph_addr
+                    .seen
+                    .and_then(|txid| self.tx_table.get(&txid))
+                    .and_then(|tx| tx.mined_height())
+                {
+                    idx = tidx.checked_add(1).unwrap();
+                    break;
+                }
+            }
+            idx
+        } else {
+            0
+        };
+
+        Ok(min(
+            1 << 31,
+            first_unmined_index.checked_add(GAP_LIMIT).unwrap(),
+        ))
+    }
+
+    pub fn get_funding_accounts(&self, tx: &Transaction) -> Result<BTreeSet<AccountId>, Error> {
+        let mut funding_accounts = BTreeSet::new();
+        #[cfg(feature = "transparent-inputs")]
+        funding_accounts.extend(
+            self.transparent_received_outputs.detect_spending_accounts(
+                tx.transparent_bundle()
+                    .iter()
+                    .flat_map(|bundle| bundle.vin.iter().map(|txin| &txin.prevout)),
+            )?,
+        );
+
+        funding_accounts.extend(self.received_notes.detect_sapling_spending_accounts(
+            tx.sapling_bundle().iter().flat_map(|bundle| {
+                bundle
+                    .shielded_spends()
+                    .iter()
+                    .map(|spend| spend.nullifier())
+            }),
+        )?);
+
+        #[cfg(feature = "orchard")]
+        funding_accounts.extend(
+            self.received_notes.detect_orchard_spending_accounts(
+                tx.orchard_bundle()
+                    .iter()
+                    .flat_map(|bundle| bundle.actions().iter().map(|action| action.nullifier())),
+            )?,
+        );
+
+        Ok(funding_accounts)
+    }
+
     pub(crate) fn get_received_notes(&self) -> &ReceivedNoteTable {
         &self.received_notes
     }
@@ -906,20 +965,12 @@ impl<P: consensus::Parameters> MemoryWalletDb<P> {
         }
     }
 
+    #[cfg(feature = "transparent-inputs")]
     pub(crate) fn find_account_for_transparent_address(
         &self,
         address: &TransparentAddress,
     ) -> Result<Option<AccountId>, Error> {
-        Ok(self
-            .accounts
-            .iter()
-            .find(|(_, account)| {
-                account
-                    .addresses()
-                    .iter()
-                    .any(|(_, unified_address)| unified_address.transparent() == Some(address))
-            })
-            .map(|(id, _)| id.clone()))
+        self.accounts.find_account_for_transparent_address(address)
     }
 
     pub(crate) fn mark_transparent_output_spent(
@@ -1027,7 +1078,6 @@ impl<P: consensus::Parameters> MemoryWalletDb<P> {
 
 #[cfg(test)]
 mod test {
-
     use ciborium::into_writer;
 
     use crate::MemoryWalletDb;

zcash_client_memory/src/testing/mod.rs

@@ -109,22 +109,29 @@ where
                     receiving_account,
                     ..
                 } => {
-                    let account = self.get_account(receiving_account)?.unwrap();
-                    let idx = *account
-                        .addresses()
-                        .iter()
-                        .find(|(_, addr)| addr.transparent() == Some(&ephemeral_address))
-                        .unwrap()
-                        .0;
-                    let idx = idx.try_into().unwrap();
-
-                    Ok((
-                        // TODO: Use the ephemeral address index to look up the address
-                        // and find the correct index
-                        note.value.into_u64(),
-                        Some(Address::from(ephemeral_address)),
-                        Some((Address::from(ephemeral_address), idx)),
-                    ))
+                    #[cfg(feature = "transparent-inputs")]
+                    {
+                        let account = self.get_account(receiving_account)?.unwrap();
+                        let (_addr, meta) = account
+                            .ephemeral_addresses()?
+                            .into_iter()
+                            .find(|(addr, _)| addr == &ephemeral_address)
+                            .unwrap();
+                        Ok((
+                            // TODO: Use the ephemeral address index to look up the address
+                            // and find the correct index
+                            note.value.into_u64(),
+                            Some(Address::from(ephemeral_address)),
+                            Some((
+                                Address::from(ephemeral_address),
+                                meta.address_index().index(),
+                            )),
+                        ))
+                    }
+                    #[cfg(not(feature = "transparent-inputs"))]
+                    {
+                        unimplemented!("EphemeralTransparent recipients are not supported without the `transparent-inputs` feature.")
+                    }
                 }
                 Recipient::InternalAccount { .. } => Ok((note.value.into_u64(), None, None)),
             })