From d10a2b78b1100aba9122afb526f7d456c9cbedd1 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Sat, 27 Feb 2021 10:56:50 -0300
Subject: [PATCH 01/29] add transaction V5 stub

---
 zebra-chain/src/transaction.rs           | 19 +++++++++++++++++++
 zebra-chain/src/transaction/serialize.rs | 18 ++++++++++++++++++
 zebra-chain/src/transaction/sighash.rs   | 17 ++++++++++++-----
 zebra-consensus/src/transaction.rs       |  5 ++++-
 zebra-consensus/src/transaction/check.rs | 10 ++++++++--
 zebra-state/src/tests.rs                 |  1 +
 6 files changed, 62 insertions(+), 8 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index 1d8401f643e..23bd30258b8 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -99,6 +99,21 @@ pub enum Transaction {
         /// The shielded data for this transaction, if any.
         shielded_data: Option<ShieldedData>,
     },
+    /// An Orchard transaction (`version = 5`).
+    V5 {
+        /// The transparent inputs to the transaction.
+        tx_in: Vec<transparent::Input>,
+        /// The transparent outputs from the transaction.
+        tx_out: Vec<transparent::Output>,
+        /// The earliest time or block height that this transaction can be added to the
+        /// chain.
+        lock_time: LockTime,
+        /// The latest block height that this transaction can be added to the chain.
+        expiry_height: block::Height,
+
+        /// The rest of the transaction as bytes
+        rest: Vec<u8>,
+    },
 }
 
 impl Transaction {
@@ -114,6 +129,7 @@ impl Transaction {
             Transaction::V2 { ref inputs, .. } => inputs,
             Transaction::V3 { ref inputs, .. } => inputs,
             Transaction::V4 { ref inputs, .. } => inputs,
+            Transaction::V5 { ref tx_in, .. } => tx_in,
         }
     }
 
@@ -124,6 +140,7 @@ impl Transaction {
             Transaction::V2 { ref outputs, .. } => outputs,
             Transaction::V3 { ref outputs, .. } => outputs,
             Transaction::V4 { ref outputs, .. } => outputs,
+            Transaction::V5 { ref tx_out, .. } => tx_out,
         }
     }
 
@@ -134,6 +151,7 @@ impl Transaction {
             Transaction::V2 { lock_time, .. } => *lock_time,
             Transaction::V3 { lock_time, .. } => *lock_time,
             Transaction::V4 { lock_time, .. } => *lock_time,
+            Transaction::V5 { lock_time, .. } => *lock_time,
         }
     }
 
@@ -144,6 +162,7 @@ impl Transaction {
             Transaction::V2 { .. } => None,
             Transaction::V3 { expiry_height, .. } => Some(*expiry_height),
             Transaction::V4 { expiry_height, .. } => Some(*expiry_height),
+            Transaction::V5 { expiry_height, .. } => Some(*expiry_height),
         }
     }
 
diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index dc9c28fa776..2fa6fd8883f 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -18,6 +18,7 @@ use super::*;
 
 const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
 const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
+const ORCHARD_VERSION_GROUP_ID: u32 = 0x6A7_270A;
 
 impl ZcashDeserialize for jubjub::Fq {
     fn zcash_deserialize<R: io::Read>(mut reader: R) -> Result<Self, SerializationError> {
@@ -182,6 +183,23 @@ impl ZcashSerialize for Transaction {
                     None => {}
                 }
             }
+            Transaction::V5 {
+                tx_in,
+                tx_out,
+                lock_time,
+                expiry_height,
+                rest,
+            } => {
+                // Write version 4 and set the fOverwintered bit.
+                writer.write_u32::<LittleEndian>(4 | (1 << 31))?;
+                writer.write_u32::<LittleEndian>(ORCHARD_VERSION_GROUP_ID)?;
+                tx_in.zcash_serialize(&mut writer)?;
+                tx_out.zcash_serialize(&mut writer)?;
+                lock_time.zcash_serialize(&mut writer)?;
+                writer.write_u32::<LittleEndian>(expiry_height.0)?;
+                // write the rest
+                writer.write_all(rest)?;
+            }
         }
         Ok(())
     }
diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index 525b503523e..fc5795386ce 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -14,6 +14,7 @@ static ZIP243_EXPLANATION: &str = "Invalid transaction version: after Sapling ac
 
 const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
 const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
+const ORCHARD_VERSION_GROUP_ID: u32 = 0x6A7_270A;
 
 const ZCASH_SIGHASH_PERSONALIZATION_PREFIX: &[u8; 12] = b"ZcashSigHash";
 const ZCASH_PREVOUTS_HASH_PERSONALIZATION: &[u8; 16] = b"ZcashPrevoutHash";
@@ -129,6 +130,7 @@ impl<'a> SigHasher<'a> {
             Transaction::V1 { .. } | Transaction::V2 { .. } => unreachable!(ZIP143_EXPLANATION),
             Transaction::V3 { .. } => 3 | overwintered_flag,
             Transaction::V4 { .. } => 4 | overwintered_flag,
+            Transaction::V5 { .. } => 5 | overwintered_flag,
         })
     }
 
@@ -137,6 +139,7 @@ impl<'a> SigHasher<'a> {
             Transaction::V1 { .. } | Transaction::V2 { .. } => unreachable!(ZIP143_EXPLANATION),
             Transaction::V3 { .. } => OVERWINTER_VERSION_GROUP_ID,
             Transaction::V4 { .. } => SAPLING_VERSION_GROUP_ID,
+            Transaction::V5 { .. } => ORCHARD_VERSION_GROUP_ID,
         })
     }
 
@@ -243,6 +246,7 @@ impl<'a> SigHasher<'a> {
             Transaction::V1 { .. } | Transaction::V2 { .. } => unreachable!(ZIP143_EXPLANATION),
             Transaction::V3 { joinsplit_data, .. } => joinsplit_data.is_some(),
             Transaction::V4 { joinsplit_data, .. } => joinsplit_data.is_some(),
+            Transaction::V5 { .. } => unimplemented!("v5 transaction"),
         };
 
         if !has_joinsplits {
@@ -398,14 +402,15 @@ impl<'a> SigHasher<'a> {
         use Transaction::*;
 
         let shielded_data = match self.trans {
-            Transaction::V4 {
+            V4 {
                 shielded_data: Some(shielded_data),
                 ..
             } => shielded_data,
-            Transaction::V4 {
+            V4 {
                 shielded_data: None,
                 ..
             } => return writer.write_all(&[0; 32]),
+            V5 { .. } => unimplemented!("v5 transaction"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 
@@ -434,14 +439,15 @@ impl<'a> SigHasher<'a> {
         use Transaction::*;
 
         let shielded_data = match self.trans {
-            Transaction::V4 {
+            V4 {
                 shielded_data: Some(shielded_data),
                 ..
             } => shielded_data,
-            Transaction::V4 {
+            V4 {
                 shielded_data: None,
                 ..
             } => return writer.write_all(&[0; 32]),
+            V5 { .. } => unimplemented!("v5 transaction"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 
@@ -465,7 +471,8 @@ impl<'a> SigHasher<'a> {
         use Transaction::*;
 
         let value_balance = match self.trans {
-            Transaction::V4 { value_balance, .. } => value_balance,
+            V4 { value_balance, .. } => value_balance,
+            V5 { .. } => unreachable!("NOT IMPLEMENTED YET!"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 
diff --git a/zebra-consensus/src/transaction.rs b/zebra-consensus/src/transaction.rs
index ae684ae9fa4..33244f9ba44 100644
--- a/zebra-consensus/src/transaction.rs
+++ b/zebra-consensus/src/transaction.rs
@@ -132,7 +132,10 @@ where
         async move {
             tracing::trace!(?tx);
             match &*tx {
-                Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+                Transaction::V1 { .. }
+                | Transaction::V2 { .. }
+                | Transaction::V3 { .. }
+                | Transaction::V5 { .. } => {
                     tracing::debug!(?tx, "got transaction with wrong version");
                     Err(TransactionError::WrongVersion)
                 }
diff --git a/zebra-consensus/src/transaction/check.rs b/zebra-consensus/src/transaction/check.rs
index fb2316ab8ba..710ede6bf3d 100644
--- a/zebra-consensus/src/transaction/check.rs
+++ b/zebra-consensus/src/transaction/check.rs
@@ -68,7 +68,10 @@ pub fn has_inputs_and_outputs(tx: &Transaction) -> Result<(), TransactionError>
                 Ok(())
             }
         }
-        Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+        Transaction::V1 { .. }
+        | Transaction::V2 { .. }
+        | Transaction::V3 { .. }
+        | Transaction::V5 { .. } => {
             unreachable!("tx version is checked first")
         }
     }
@@ -111,7 +114,10 @@ pub fn coinbase_tx_no_joinsplit_or_spend(tx: &Transaction) -> Result<(), Transac
 
             Transaction::V4 { .. } => Ok(()),
 
-            Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+            Transaction::V1 { .. }
+            | Transaction::V2 { .. }
+            | Transaction::V3 { .. }
+            | Transaction::V5 { .. } => {
                 unreachable!("tx version is checked first")
             }
         }
diff --git a/zebra-state/src/tests.rs b/zebra-state/src/tests.rs
index 8510504fe18..457a0dfe200 100644
--- a/zebra-state/src/tests.rs
+++ b/zebra-state/src/tests.rs
@@ -53,6 +53,7 @@ impl FakeChainHelper for Arc<Block> {
             Transaction::V2 { inputs, .. } => &mut inputs[0],
             Transaction::V3 { inputs, .. } => &mut inputs[0],
             Transaction::V4 { inputs, .. } => &mut inputs[0],
+            Transaction::V5 { tx_in, .. } => &mut tx_in[0],
         };
 
         match input {

From dc014d5eef06e4386bebc2992359d534da058ae6 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Sat, 27 Feb 2021 13:58:23 -0300
Subject: [PATCH 02/29] add v5_strategy

---
 zebra-chain/src/transaction/arbitrary.rs | 25 +++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/zebra-chain/src/transaction/arbitrary.rs b/zebra-chain/src/transaction/arbitrary.rs
index c34da137b33..cea6caf416c 100644
--- a/zebra-chain/src/transaction/arbitrary.rs
+++ b/zebra-chain/src/transaction/arbitrary.rs
@@ -104,6 +104,26 @@ impl Transaction {
             )
             .boxed()
     }
+    /// Generate a proptest strategy for V5 Transactions
+    pub fn v5_strategy(ledger_state: LedgerState) -> BoxedStrategy<Self> {
+        (
+            transparent::Input::vec_strategy(ledger_state, 10),
+            vec(any::<transparent::Output>(), 0..10),
+            any::<LockTime>(),
+            any::<block::Height>(),
+            any::<Vec<u8>>(),
+        )
+            .prop_map(
+                |(tx_in, tx_out, lock_time, expiry_height, rest)| Transaction::V5 {
+                    tx_in,
+                    tx_out,
+                    lock_time,
+                    expiry_height,
+                    rest,
+                },
+            )
+            .boxed()
+    }
 
     /// Proptest Strategy for creating a Vector of transactions where the first
     /// transaction is always the only coinbase transaction
@@ -236,9 +256,8 @@ impl Arbitrary for Transaction {
             NetworkUpgrade::Blossom | NetworkUpgrade::Heartwood | NetworkUpgrade::Canopy => {
                 Self::v4_strategy(ledger_state)
             }
-            NetworkUpgrade::NU5 => {
-                unimplemented!("NU5 upgrade can use v4 or v5 transactions, as specified in ZIP-225")
-            }
+            // Blocked by #1823
+            //NetworkUpgrade::NU5 => Self::v5_strategy(ledger_state),
         }
     }
 

From 402aa9ed24f8d5a62906f0184b1d539382f12b0d Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Sat, 27 Feb 2021 14:52:01 -0300
Subject: [PATCH 03/29] deduplicate version group ids

---
 zebra-chain/src/parameters.rs             | 2 ++
 zebra-chain/src/parameters/transaction.rs | 8 ++++++++
 zebra-chain/src/transaction/serialize.rs  | 5 +----
 zebra-chain/src/transaction/sighash.rs    | 9 ++++-----
 4 files changed, 15 insertions(+), 9 deletions(-)
 create mode 100644 zebra-chain/src/parameters/transaction.rs

diff --git a/zebra-chain/src/parameters.rs b/zebra-chain/src/parameters.rs
index 0fa86428d44..ff369e79853 100644
--- a/zebra-chain/src/parameters.rs
+++ b/zebra-chain/src/parameters.rs
@@ -15,10 +15,12 @@
 mod genesis;
 mod network;
 mod network_upgrade;
+mod transaction;
 
 pub use genesis::*;
 pub use network::Network;
 pub use network_upgrade::*;
+pub use transaction::*;
 
 #[cfg(test)]
 mod tests;
diff --git a/zebra-chain/src/parameters/transaction.rs b/zebra-chain/src/parameters/transaction.rs
new file mode 100644
index 00000000000..a0857dd10a9
--- /dev/null
+++ b/zebra-chain/src/parameters/transaction.rs
@@ -0,0 +1,8 @@
+//! Transaction consensus and utility parameters.
+
+///The Overwinter version group ID.
+pub const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
+///The Sapling version group ID.
+pub const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
+///The Orchard version group ID.
+pub const ORCHARD_VERSION_GROUP_ID: u32 = 0x6A7_270A;
diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index 2fa6fd8883f..d6ac55b6e23 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -6,6 +6,7 @@ use std::{io, sync::Arc};
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 
 use crate::{
+    parameters::{ORCHARD_VERSION_GROUP_ID, OVERWINTER_VERSION_GROUP_ID, SAPLING_VERSION_GROUP_ID},
     primitives::ZkSnarkProof,
     serialization::{
         ReadZcashExt, SerializationError, WriteZcashExt, ZcashDeserialize, ZcashDeserializeInto,
@@ -16,10 +17,6 @@ use crate::{
 
 use super::*;
 
-const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
-const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
-const ORCHARD_VERSION_GROUP_ID: u32 = 0x6A7_270A;
-
 impl ZcashDeserialize for jubjub::Fq {
     fn zcash_deserialize<R: io::Read>(mut reader: R) -> Result<Self, SerializationError> {
         let possible_scalar = jubjub::Fq::from_bytes(&reader.read_32_bytes()?);
diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index fc5795386ce..033cb17fc6e 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -1,6 +1,9 @@
 use super::Transaction;
 use crate::{
-    parameters::{ConsensusBranchId, NetworkUpgrade},
+    parameters::{
+        ConsensusBranchId, NetworkUpgrade, ORCHARD_VERSION_GROUP_ID, OVERWINTER_VERSION_GROUP_ID,
+        SAPLING_VERSION_GROUP_ID,
+    },
     serialization::{WriteZcashExt, ZcashSerialize},
     transparent,
 };
@@ -12,10 +15,6 @@ use std::io;
 static ZIP143_EXPLANATION: &str = "Invalid transaction version: after Overwinter activation transaction versions 1 and 2 are rejected";
 static ZIP243_EXPLANATION: &str = "Invalid transaction version: after Sapling activation transaction versions 1, 2, and 3 are rejected";
 
-const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
-const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
-const ORCHARD_VERSION_GROUP_ID: u32 = 0x6A7_270A;
-
 const ZCASH_SIGHASH_PERSONALIZATION_PREFIX: &[u8; 12] = b"ZcashSigHash";
 const ZCASH_PREVOUTS_HASH_PERSONALIZATION: &[u8; 16] = b"ZcashPrevoutHash";
 const ZCASH_SEQUENCE_HASH_PERSONALIZATION: &[u8; 16] = b"ZcashSequencHash";

From ba1890f2be06271628a8099895289bd7fa2a318a Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Sat, 27 Feb 2021 14:58:56 -0300
Subject: [PATCH 04/29] fix version in serialize

---
 zebra-chain/src/transaction/serialize.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index d6ac55b6e23..440b03260fd 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -187,8 +187,8 @@ impl ZcashSerialize for Transaction {
                 expiry_height,
                 rest,
             } => {
-                // Write version 4 and set the fOverwintered bit.
-                writer.write_u32::<LittleEndian>(4 | (1 << 31))?;
+                // Write version 5 and set the fOverwintered bit.
+                writer.write_u32::<LittleEndian>(5 | (1 << 31))?;
                 writer.write_u32::<LittleEndian>(ORCHARD_VERSION_GROUP_ID)?;
                 tx_in.zcash_serialize(&mut writer)?;
                 tx_out.zcash_serialize(&mut writer)?;

From 5745db89735a528b0e4cc2e21f2256780da7f81a Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Sat, 27 Feb 2021 20:29:30 -0300
Subject: [PATCH 05/29] replace an unreachable

---
 zebra-chain/src/transaction/sighash.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index 033cb17fc6e..400c50a02a2 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -471,7 +471,7 @@ impl<'a> SigHasher<'a> {
 
         let value_balance = match self.trans {
             V4 { value_balance, .. } => value_balance,
-            V5 { .. } => unreachable!("NOT IMPLEMENTED YET!"),
+            V5 { .. } => unimplemented!("v5 transaction"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 

From 7356b861e2616fe5aa24d1ae93283813bdcf19b8 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Mon, 1 Mar 2021 11:35:18 +1000
Subject: [PATCH 06/29] Update comment for V5 transactions

---
 zebra-chain/src/transaction.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index 23bd30258b8..1a64a78cf37 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -42,7 +42,7 @@ use crate::{
 /// internally by different enum variants. Because we checkpoint on Sapling
 /// activation, we do not validate any pre-Sapling transaction types.
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
-// XXX consider boxing the Optional fields of V4 txs
+// XXX consider boxing the Optional fields of V4 and V5 txs
 #[allow(clippy::large_enum_variant)]
 pub enum Transaction {
     /// A fully transparent transaction (`version = 1`).

From 32fdcff0d65d6c4b7e69581525f1cc839dc02166 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Mon, 1 Mar 2021 12:30:05 +1000
Subject: [PATCH 07/29] Add V5 transactions to non_finalized_state

Currently these are all `unimplemented!(...)`
---
 zebra-state/src/service/non_finalized_state/chain.rs | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/zebra-state/src/service/non_finalized_state/chain.rs b/zebra-state/src/service/non_finalized_state/chain.rs
index 82946e6ceef..7aa5d1268ae 100644
--- a/zebra-state/src/service/non_finalized_state/chain.rs
+++ b/zebra-state/src/service/non_finalized_state/chain.rs
@@ -165,14 +165,16 @@ impl UpdateWith<PreparedBlock> for Chain {
             .zip(transaction_hashes.iter().cloned())
             .enumerate()
         {
+            use transaction::Transaction::*;
             let (inputs, shielded_data, joinsplit_data) = match transaction.deref() {
-                transaction::Transaction::V4 {
+                V4 {
                     inputs,
                     shielded_data,
                     joinsplit_data,
                     ..
                 } => (inputs, shielded_data, joinsplit_data),
-                _ => unreachable!(
+                V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
+                V1 | V2 | V3 => unreachable!(
                     "older transaction versions only exist in finalized blocks pre sapling",
                 ),
             };
@@ -223,14 +225,16 @@ impl UpdateWith<PreparedBlock> for Chain {
         for (transaction, transaction_hash) in
             block.transactions.iter().zip(transaction_hashes.iter())
         {
+            use transaction::Transaction::*;
             let (inputs, shielded_data, joinsplit_data) = match transaction.deref() {
-                transaction::Transaction::V4 {
+                V4 {
                     inputs,
                     shielded_data,
                     joinsplit_data,
                     ..
                 } => (inputs, shielded_data, joinsplit_data),
-                _ => unreachable!(
+                V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
+                V1 | V2 | V3 => unreachable!(
                     "older transaction versions only exist in finalized blocks pre sapling",
                 ),
             };

From 092543be9d3fec946f8015b57009190e6c6eb9c8 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Mon, 1 Mar 2021 13:08:20 +1000
Subject: [PATCH 08/29] Fix struct matches

---
 zebra-state/src/service/non_finalized_state/chain.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/zebra-state/src/service/non_finalized_state/chain.rs b/zebra-state/src/service/non_finalized_state/chain.rs
index 7aa5d1268ae..1a302e6f394 100644
--- a/zebra-state/src/service/non_finalized_state/chain.rs
+++ b/zebra-state/src/service/non_finalized_state/chain.rs
@@ -174,7 +174,7 @@ impl UpdateWith<PreparedBlock> for Chain {
                     ..
                 } => (inputs, shielded_data, joinsplit_data),
                 V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
-                V1 | V2 | V3 => unreachable!(
+                V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(
                     "older transaction versions only exist in finalized blocks pre sapling",
                 ),
             };
@@ -234,7 +234,7 @@ impl UpdateWith<PreparedBlock> for Chain {
                     ..
                 } => (inputs, shielded_data, joinsplit_data),
                 V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
-                V1 | V2 | V3 => unreachable!(
+                V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(
                     "older transaction versions only exist in finalized blocks pre sapling",
                 ),
             };

From c19c8dce9d83ab2b8c22353925987b383b62af11 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Mon, 1 Mar 2021 13:40:15 +1000
Subject: [PATCH 09/29] Apply trivial panic message changes

---
 zebra-chain/src/transaction/sighash.rs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index 400c50a02a2..e9122a81974 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -245,7 +245,7 @@ impl<'a> SigHasher<'a> {
             Transaction::V1 { .. } | Transaction::V2 { .. } => unreachable!(ZIP143_EXPLANATION),
             Transaction::V3 { joinsplit_data, .. } => joinsplit_data.is_some(),
             Transaction::V4 { joinsplit_data, .. } => joinsplit_data.is_some(),
-            Transaction::V5 { .. } => unimplemented!("v5 transaction"),
+            Transaction::V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
         };
 
         if !has_joinsplits {
@@ -409,7 +409,7 @@ impl<'a> SigHasher<'a> {
                 shielded_data: None,
                 ..
             } => return writer.write_all(&[0; 32]),
-            V5 { .. } => unimplemented!("v5 transaction"),
+            V5 { .. } => unimplemented!("v5 transaction hash as specified in ZIP-225 and ZIP-244"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 
@@ -446,7 +446,7 @@ impl<'a> SigHasher<'a> {
                 shielded_data: None,
                 ..
             } => return writer.write_all(&[0; 32]),
-            V5 { .. } => unimplemented!("v5 transaction"),
+            V5 { .. } => unimplemented!("v5 transaction hash as specified in ZIP-225 and ZIP-244"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 
@@ -471,7 +471,7 @@ impl<'a> SigHasher<'a> {
 
         let value_balance = match self.trans {
             V4 { value_balance, .. } => value_balance,
-            V5 { .. } => unimplemented!("v5 transaction"),
+            V5 { .. } => unimplemented!("v5 transaction hash as specified in ZIP-225 and ZIP-244"),
             V1 { .. } | V2 { .. } | V3 { .. } => unreachable!(ZIP243_EXPLANATION),
         };
 

From 3817ecdc5a5bb104afc475fd39cc57e3d775f0cd Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Mon, 1 Mar 2021 13:44:49 +1000
Subject: [PATCH 10/29] rustfmt

---
 zebra-chain/src/transaction/sighash.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index e9122a81974..7db2238eeb6 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -245,7 +245,9 @@ impl<'a> SigHasher<'a> {
             Transaction::V1 { .. } | Transaction::V2 { .. } => unreachable!(ZIP143_EXPLANATION),
             Transaction::V3 { joinsplit_data, .. } => joinsplit_data.is_some(),
             Transaction::V4 { joinsplit_data, .. } => joinsplit_data.is_some(),
-            Transaction::V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
+            Transaction::V5 { .. } => {
+                unimplemented!("v5 transaction format as specified in ZIP-225")
+            }
         };
 
         if !has_joinsplits {

From 7bf53563aa2800d59aa6239b3afcc7bcaa178fc3 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 10:07:35 -0300
Subject: [PATCH 11/29] use TX_V5_VERSION_GROUP_ID

---
 zebra-chain/src/parameters/transaction.rs | 13 +++++++++----
 zebra-chain/src/transaction/serialize.rs  |  4 ++--
 zebra-chain/src/transaction/sighash.rs    |  6 +++---
 3 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/zebra-chain/src/parameters/transaction.rs b/zebra-chain/src/parameters/transaction.rs
index a0857dd10a9..01d5175b940 100644
--- a/zebra-chain/src/parameters/transaction.rs
+++ b/zebra-chain/src/parameters/transaction.rs
@@ -1,8 +1,13 @@
 //! Transaction consensus and utility parameters.
 
-///The Overwinter version group ID.
+///The version group ID for Overwinter transactions.
 pub const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
-///The Sapling version group ID.
+
+///The version group ID for Sapling transactions.
 pub const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
-///The Orchard version group ID.
-pub const ORCHARD_VERSION_GROUP_ID: u32 = 0x6A7_270A;
+
+/// The version group ID for version 5 transactions.
+///
+/// Orchard transactions must use transaction version 5 and this version
+/// group ID. Sapling transactions can use v4 or v5 transactions.
+pub const TX_V5_VERSION_GROUP_ID: u32 = 0x26A7_270A;
diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index 440b03260fd..31adcea2346 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -6,7 +6,7 @@ use std::{io, sync::Arc};
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 
 use crate::{
-    parameters::{ORCHARD_VERSION_GROUP_ID, OVERWINTER_VERSION_GROUP_ID, SAPLING_VERSION_GROUP_ID},
+    parameters::{OVERWINTER_VERSION_GROUP_ID, SAPLING_VERSION_GROUP_ID, TX_V5_VERSION_GROUP_ID},
     primitives::ZkSnarkProof,
     serialization::{
         ReadZcashExt, SerializationError, WriteZcashExt, ZcashDeserialize, ZcashDeserializeInto,
@@ -189,7 +189,7 @@ impl ZcashSerialize for Transaction {
             } => {
                 // Write version 5 and set the fOverwintered bit.
                 writer.write_u32::<LittleEndian>(5 | (1 << 31))?;
-                writer.write_u32::<LittleEndian>(ORCHARD_VERSION_GROUP_ID)?;
+                writer.write_u32::<LittleEndian>(TX_V5_VERSION_GROUP_ID)?;
                 tx_in.zcash_serialize(&mut writer)?;
                 tx_out.zcash_serialize(&mut writer)?;
                 lock_time.zcash_serialize(&mut writer)?;
diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index 7db2238eeb6..b63d2688681 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -1,8 +1,8 @@
 use super::Transaction;
 use crate::{
     parameters::{
-        ConsensusBranchId, NetworkUpgrade, ORCHARD_VERSION_GROUP_ID, OVERWINTER_VERSION_GROUP_ID,
-        SAPLING_VERSION_GROUP_ID,
+        ConsensusBranchId, NetworkUpgrade, OVERWINTER_VERSION_GROUP_ID, SAPLING_VERSION_GROUP_ID,
+        TX_V5_VERSION_GROUP_ID,
     },
     serialization::{WriteZcashExt, ZcashSerialize},
     transparent,
@@ -138,7 +138,7 @@ impl<'a> SigHasher<'a> {
             Transaction::V1 { .. } | Transaction::V2 { .. } => unreachable!(ZIP143_EXPLANATION),
             Transaction::V3 { .. } => OVERWINTER_VERSION_GROUP_ID,
             Transaction::V4 { .. } => SAPLING_VERSION_GROUP_ID,
-            Transaction::V5 { .. } => ORCHARD_VERSION_GROUP_ID,
+            Transaction::V5 { .. } => TX_V5_VERSION_GROUP_ID,
         })
     }
 

From 2d428ff9078355fd95a424a2e475a3466cbdde4b Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 10:10:44 -0300
Subject: [PATCH 12/29] fix comment, spacing

---
 zebra-chain/src/parameters/transaction.rs | 4 ++--
 zebra-chain/src/transaction.rs            | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/zebra-chain/src/parameters/transaction.rs b/zebra-chain/src/parameters/transaction.rs
index 01d5175b940..bab59e794db 100644
--- a/zebra-chain/src/parameters/transaction.rs
+++ b/zebra-chain/src/parameters/transaction.rs
@@ -1,9 +1,9 @@
 //! Transaction consensus and utility parameters.
 
-///The version group ID for Overwinter transactions.
+/// The version group ID for Overwinter transactions.
 pub const OVERWINTER_VERSION_GROUP_ID: u32 = 0x03C4_8270;
 
-///The version group ID for Sapling transactions.
+/// The version group ID for Sapling transactions.
 pub const SAPLING_VERSION_GROUP_ID: u32 = 0x892F_2085;
 
 /// The version group ID for version 5 transactions.
diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index 1a64a78cf37..ab75b564d27 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -99,7 +99,7 @@ pub enum Transaction {
         /// The shielded data for this transaction, if any.
         shielded_data: Option<ShieldedData>,
     },
-    /// An Orchard transaction (`version = 5`).
+    /// A `version = 5` transaction, which supports `Sapling` and `Orchard`.
     V5 {
         /// The transparent inputs to the transaction.
         tx_in: Vec<transparent::Input>,

From 37eadb7775a8bb5925bf49d9bb090c8c9a81cb1e Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 12:37:53 -0300
Subject: [PATCH 13/29] add zcash_deserialize for V5

---
 zebra-chain/src/transaction/serialize.rs | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index 31adcea2346..900c0bce523 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -300,6 +300,23 @@ impl ZcashDeserialize for Transaction {
                     joinsplit_data,
                 })
             }
+            (5, false) => {
+                let id = reader.read_u32::<LittleEndian>()?;
+                if id != TX_V5_VERSION_GROUP_ID {
+                    return Err(SerializationError::Parse("expected TX_V5_VERSION_GROUP_ID"));
+                }
+                Ok(Transaction::V5 {
+                    tx_in: Vec::zcash_deserialize(&mut reader)?,
+                    tx_out: Vec::zcash_deserialize(&mut reader)?,
+                    lock_time: LockTime::zcash_deserialize(&mut reader)?,
+                    expiry_height: block::Height(reader.read_u32::<LittleEndian>()?),
+                    rest: {
+                        let mut buffer = Vec::new();
+                        reader.read_to_end(&mut buffer)?;
+                        buffer
+                    },
+                })
+            }
             (_, _) => Err(SerializationError::Parse("bad tx header")),
         }
     }

From 8c333820b31b617d8e20c1a4ed55232be4267b36 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 14:05:34 -0300
Subject: [PATCH 14/29] change blocked code in arbitrary

---
 zebra-chain/src/transaction/arbitrary.rs | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/zebra-chain/src/transaction/arbitrary.rs b/zebra-chain/src/transaction/arbitrary.rs
index cea6caf416c..c0297937009 100644
--- a/zebra-chain/src/transaction/arbitrary.rs
+++ b/zebra-chain/src/transaction/arbitrary.rs
@@ -256,8 +256,13 @@ impl Arbitrary for Transaction {
             NetworkUpgrade::Blossom | NetworkUpgrade::Heartwood | NetworkUpgrade::Canopy => {
                 Self::v4_strategy(ledger_state)
             }
-            // Blocked by #1823
-            //NetworkUpgrade::NU5 => Self::v5_strategy(ledger_state),
+            // Blocked by #1823 and #1824, see #1826
+            /*
+            NetworkUpgrade::NU5 => prop_oneof!(
+                Self::v4_strategy(ledger_state),
+                Self::v5_strategy(ledger_state)
+            ),
+            */
         }
     }
 

From 21fd59b0294555bfa0ca4ba3002a99c66ad9ee16 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 14:35:35 -0300
Subject: [PATCH 15/29] make all tx versions explicit in sprout and sapling
 nullifier functions

---
 zebra-chain/src/transaction.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index ab75b564d27..6fd9aed9cbd 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -194,7 +194,8 @@ impl Transaction {
                     .flat_map(|joinsplit| joinsplit.nullifiers.iter()),
             ),
             // No JoinSplits
-            _ => Box::new(std::iter::empty()),
+            Transaction::V1 { .. } | Transaction::V5 { .. } => Box::new(std::iter::empty()),
+            _ => Box::new(std::iter::empty())
         }
     }
 
@@ -208,8 +209,10 @@ impl Transaction {
                 shielded_data: Some(shielded_data),
                 ..
             } => Box::new(shielded_data.nullifiers()),
+            Transaction::V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
             // No JoinSplits
-            _ => Box::new(std::iter::empty()),
+            Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => Box::new(std::iter::empty()),
+            _ => Box::new(std::iter::empty())
         }
     }
 

From e8510471bc6f6138502b5b1ced661a40e51201b4 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 14:38:57 -0300
Subject: [PATCH 16/29] rustfmt

---
 zebra-chain/src/transaction/arbitrary.rs | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/zebra-chain/src/transaction/arbitrary.rs b/zebra-chain/src/transaction/arbitrary.rs
index c0297937009..1ef7a01d24d 100644
--- a/zebra-chain/src/transaction/arbitrary.rs
+++ b/zebra-chain/src/transaction/arbitrary.rs
@@ -255,14 +255,13 @@ impl Arbitrary for Transaction {
             NetworkUpgrade::Sapling => Self::v3_strategy(ledger_state),
             NetworkUpgrade::Blossom | NetworkUpgrade::Heartwood | NetworkUpgrade::Canopy => {
                 Self::v4_strategy(ledger_state)
-            }
-            // Blocked by #1823 and #1824, see #1826
-            /*
-            NetworkUpgrade::NU5 => prop_oneof!(
-                Self::v4_strategy(ledger_state),
-                Self::v5_strategy(ledger_state)
-            ),
-            */
+            } // Blocked by #1823 and #1824, see #1826
+              /*
+              NetworkUpgrade::NU5 => prop_oneof!(
+                  Self::v4_strategy(ledger_state),
+                  Self::v5_strategy(ledger_state)
+              ),
+              */
         }
     }
 

From 41d0c695c3c977c46d6e8037d440e80f54894250 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 14:57:46 -0300
Subject: [PATCH 17/29] rustfmt

---
 zebra-chain/src/transaction.rs | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index 6fd9aed9cbd..732ba332793 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -195,7 +195,7 @@ impl Transaction {
             ),
             // No JoinSplits
             Transaction::V1 { .. } | Transaction::V5 { .. } => Box::new(std::iter::empty()),
-            _ => Box::new(std::iter::empty())
+            _ => Box::new(std::iter::empty()),
         }
     }
 
@@ -209,10 +209,14 @@ impl Transaction {
                 shielded_data: Some(shielded_data),
                 ..
             } => Box::new(shielded_data.nullifiers()),
-            Transaction::V5 { .. } => unimplemented!("v5 transaction format as specified in ZIP-225"),
+            Transaction::V5 { .. } => {
+                unimplemented!("v5 transaction format as specified in ZIP-225")
+            }
             // No JoinSplits
-            Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => Box::new(std::iter::empty()),
-            _ => Box::new(std::iter::empty())
+            Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+                Box::new(std::iter::empty())
+            }
+            _ => Box::new(std::iter::empty()),
         }
     }
 

From 68346ea8c95804094e751f5219ed9d905ca7cdd9 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 15:51:34 -0300
Subject: [PATCH 18/29] replace some unreacheables with unimplemented

---
 zebra-consensus/src/transaction.rs       | 3 +--
 zebra-consensus/src/transaction/check.rs | 4 ++--
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/zebra-consensus/src/transaction.rs b/zebra-consensus/src/transaction.rs
index 33244f9ba44..ee0ab877b2d 100644
--- a/zebra-consensus/src/transaction.rs
+++ b/zebra-consensus/src/transaction.rs
@@ -136,8 +136,7 @@ where
                 | Transaction::V2 { .. }
                 | Transaction::V3 { .. }
                 | Transaction::V5 { .. } => {
-                    tracing::debug!(?tx, "got transaction with wrong version");
-                    Err(TransactionError::WrongVersion)
+                    unimplemented!("v5 transaction validation as specified in ZIP-216, ZIP-224, ZIP-225, and ZIP-244")
                 }
                 Transaction::V4 {
                     inputs,
diff --git a/zebra-consensus/src/transaction/check.rs b/zebra-consensus/src/transaction/check.rs
index 710ede6bf3d..2b10d314a47 100644
--- a/zebra-consensus/src/transaction/check.rs
+++ b/zebra-consensus/src/transaction/check.rs
@@ -72,7 +72,7 @@ pub fn has_inputs_and_outputs(tx: &Transaction) -> Result<(), TransactionError>
         | Transaction::V2 { .. }
         | Transaction::V3 { .. }
         | Transaction::V5 { .. } => {
-            unreachable!("tx version is checked first")
+            unimplemented!("v5 transaction format as specified in ZIP-225")
         }
     }
 }
@@ -118,7 +118,7 @@ pub fn coinbase_tx_no_joinsplit_or_spend(tx: &Transaction) -> Result<(), Transac
             | Transaction::V2 { .. }
             | Transaction::V3 { .. }
             | Transaction::V5 { .. } => {
-                unreachable!("tx version is checked first")
+                unimplemented!("v5 coinbase validation as specified in ZIP-225 and the draft spec")
             }
         }
     } else {

From ef8f0f2954140774a6b487ffac241bc68872d4b1 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Mon, 1 Mar 2021 21:24:30 -0300
Subject: [PATCH 19/29] replace tx_in and tx_out with inputs and outputs

---
 zebra-chain/src/transaction.rs           |  8 ++++----
 zebra-chain/src/transaction/arbitrary.rs |  6 +++---
 zebra-chain/src/transaction/serialize.rs | 12 ++++++------
 zebra-state/src/tests.rs                 |  2 +-
 4 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index 732ba332793..df410222cd6 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -102,9 +102,9 @@ pub enum Transaction {
     /// A `version = 5` transaction, which supports `Sapling` and `Orchard`.
     V5 {
         /// The transparent inputs to the transaction.
-        tx_in: Vec<transparent::Input>,
+        inputs: Vec<transparent::Input>,
         /// The transparent outputs from the transaction.
-        tx_out: Vec<transparent::Output>,
+        outputs: Vec<transparent::Output>,
         /// The earliest time or block height that this transaction can be added to the
         /// chain.
         lock_time: LockTime,
@@ -129,7 +129,7 @@ impl Transaction {
             Transaction::V2 { ref inputs, .. } => inputs,
             Transaction::V3 { ref inputs, .. } => inputs,
             Transaction::V4 { ref inputs, .. } => inputs,
-            Transaction::V5 { ref tx_in, .. } => tx_in,
+            Transaction::V5 { ref inputs, .. } => inputs,
         }
     }
 
@@ -140,7 +140,7 @@ impl Transaction {
             Transaction::V2 { ref outputs, .. } => outputs,
             Transaction::V3 { ref outputs, .. } => outputs,
             Transaction::V4 { ref outputs, .. } => outputs,
-            Transaction::V5 { ref tx_out, .. } => tx_out,
+            Transaction::V5 { ref outputs, .. } => outputs,
         }
     }
 
diff --git a/zebra-chain/src/transaction/arbitrary.rs b/zebra-chain/src/transaction/arbitrary.rs
index 1ef7a01d24d..a79fda2f859 100644
--- a/zebra-chain/src/transaction/arbitrary.rs
+++ b/zebra-chain/src/transaction/arbitrary.rs
@@ -114,9 +114,9 @@ impl Transaction {
             any::<Vec<u8>>(),
         )
             .prop_map(
-                |(tx_in, tx_out, lock_time, expiry_height, rest)| Transaction::V5 {
-                    tx_in,
-                    tx_out,
+                |(inputs, outputs, lock_time, expiry_height, rest)| Transaction::V5 {
+                    inputs,
+                    outputs,
                     lock_time,
                     expiry_height,
                     rest,
diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index 900c0bce523..315c2d07095 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -181,8 +181,8 @@ impl ZcashSerialize for Transaction {
                 }
             }
             Transaction::V5 {
-                tx_in,
-                tx_out,
+                inputs,
+                outputs,
                 lock_time,
                 expiry_height,
                 rest,
@@ -190,8 +190,8 @@ impl ZcashSerialize for Transaction {
                 // Write version 5 and set the fOverwintered bit.
                 writer.write_u32::<LittleEndian>(5 | (1 << 31))?;
                 writer.write_u32::<LittleEndian>(TX_V5_VERSION_GROUP_ID)?;
-                tx_in.zcash_serialize(&mut writer)?;
-                tx_out.zcash_serialize(&mut writer)?;
+                inputs.zcash_serialize(&mut writer)?;
+                outputs.zcash_serialize(&mut writer)?;
                 lock_time.zcash_serialize(&mut writer)?;
                 writer.write_u32::<LittleEndian>(expiry_height.0)?;
                 // write the rest
@@ -306,8 +306,8 @@ impl ZcashDeserialize for Transaction {
                     return Err(SerializationError::Parse("expected TX_V5_VERSION_GROUP_ID"));
                 }
                 Ok(Transaction::V5 {
-                    tx_in: Vec::zcash_deserialize(&mut reader)?,
-                    tx_out: Vec::zcash_deserialize(&mut reader)?,
+                    inputs: Vec::zcash_deserialize(&mut reader)?,
+                    outputs: Vec::zcash_deserialize(&mut reader)?,
                     lock_time: LockTime::zcash_deserialize(&mut reader)?,
                     expiry_height: block::Height(reader.read_u32::<LittleEndian>()?),
                     rest: {
diff --git a/zebra-state/src/tests.rs b/zebra-state/src/tests.rs
index 457a0dfe200..247a80aa76d 100644
--- a/zebra-state/src/tests.rs
+++ b/zebra-state/src/tests.rs
@@ -53,7 +53,7 @@ impl FakeChainHelper for Arc<Block> {
             Transaction::V2 { inputs, .. } => &mut inputs[0],
             Transaction::V3 { inputs, .. } => &mut inputs[0],
             Transaction::V4 { inputs, .. } => &mut inputs[0],
-            Transaction::V5 { tx_in, .. } => &mut tx_in[0],
+            Transaction::V5 { inputs, .. } => &mut inputs[0],
         };
 
         match input {

From 02e1ff5a067d4f1dcf063aafb03b5c20372ec05c Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Tue, 2 Mar 2021 10:10:41 -0300
Subject: [PATCH 20/29] match exhaustively in sprout and sapling nullifier
 functions

---
 zebra-chain/src/transaction.rs | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index df410222cd6..f8c076db453 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -194,8 +194,20 @@ impl Transaction {
                     .flat_map(|joinsplit| joinsplit.nullifiers.iter()),
             ),
             // No JoinSplits
-            Transaction::V1 { .. } | Transaction::V5 { .. } => Box::new(std::iter::empty()),
-            _ => Box::new(std::iter::empty()),
+            Transaction::V1 { .. }
+            | Transaction::V2 {
+                joinsplit_data: None,
+                ..
+            }
+            | Transaction::V3 {
+                joinsplit_data: None,
+                ..
+            }
+            | Transaction::V4 {
+                joinsplit_data: None,
+                ..
+            }
+            | Transaction::V5 { .. } => Box::new(std::iter::empty()),
         }
     }
 
@@ -213,10 +225,13 @@ impl Transaction {
                 unimplemented!("v5 transaction format as specified in ZIP-225")
             }
             // No JoinSplits
-            Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
-                Box::new(std::iter::empty())
-            }
-            _ => Box::new(std::iter::empty()),
+            Transaction::V1 { .. }
+            | Transaction::V2 { .. }
+            | Transaction::V3 { .. }
+            | Transaction::V4 {
+                shielded_data: None,
+                ..
+            } => Box::new(std::iter::empty()),
         }
     }
 

From 5fb99635659dccc4adf1a6383dd0fbeb598d7433 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Tue, 2 Mar 2021 10:23:47 -0300
Subject: [PATCH 21/29] follow V4 let binding pattern

---
 zebra-chain/src/transaction/serialize.rs | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index 315c2d07095..3beb04d0ed5 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -305,16 +305,19 @@ impl ZcashDeserialize for Transaction {
                 if id != TX_V5_VERSION_GROUP_ID {
                     return Err(SerializationError::Parse("expected TX_V5_VERSION_GROUP_ID"));
                 }
+                let inputs = Vec::zcash_deserialize(&mut reader)?;
+                let outputs = Vec::zcash_deserialize(&mut reader)?;
+                let lock_time = LockTime::zcash_deserialize(&mut reader)?;
+                let expiry_height = block::Height(reader.read_u32::<LittleEndian>()?);
+                let mut rest = Vec::new();
+                reader.read_to_end(&mut rest)?;
+
                 Ok(Transaction::V5 {
-                    inputs: Vec::zcash_deserialize(&mut reader)?,
-                    outputs: Vec::zcash_deserialize(&mut reader)?,
-                    lock_time: LockTime::zcash_deserialize(&mut reader)?,
-                    expiry_height: block::Height(reader.read_u32::<LittleEndian>()?),
-                    rest: {
-                        let mut buffer = Vec::new();
-                        reader.read_to_end(&mut buffer)?;
-                        buffer
-                    },
+                    inputs,
+                    outputs,
+                    lock_time,
+                    expiry_height,
+                    rest,
                 })
             }
             (_, _) => Err(SerializationError::Parse("bad tx header")),

From 8302d8dcfc463dea8dd34ca52b9128142b2a4397 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Tue, 2 Mar 2021 10:40:14 -0300
Subject: [PATCH 22/29] fix matches in zebra-consensus

---
 zebra-consensus/src/transaction.rs       | 11 ++++++-----
 zebra-consensus/src/transaction/check.rs | 17 +++++++++--------
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/zebra-consensus/src/transaction.rs b/zebra-consensus/src/transaction.rs
index ee0ab877b2d..a2716dff12e 100644
--- a/zebra-consensus/src/transaction.rs
+++ b/zebra-consensus/src/transaction.rs
@@ -132,11 +132,9 @@ where
         async move {
             tracing::trace!(?tx);
             match &*tx {
-                Transaction::V1 { .. }
-                | Transaction::V2 { .. }
-                | Transaction::V3 { .. }
-                | Transaction::V5 { .. } => {
-                    unimplemented!("v5 transaction validation as specified in ZIP-216, ZIP-224, ZIP-225, and ZIP-244")
+                Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+                    tracing::debug!(?tx, "got transaction with wrong version");
+                    Err(TransactionError::WrongVersion)
                 }
                 Transaction::V4 {
                     inputs,
@@ -260,6 +258,9 @@ where
 
                     Ok(tx.hash())
                 }
+                Transaction::V5 { .. } => {
+                    unimplemented!("v5 transaction validation as specified in ZIP-216, ZIP-224, ZIP-225, and ZIP-244")
+                }
             }
         }
         .instrument(span)
diff --git a/zebra-consensus/src/transaction/check.rs b/zebra-consensus/src/transaction/check.rs
index 2b10d314a47..621ac71dd9a 100644
--- a/zebra-consensus/src/transaction/check.rs
+++ b/zebra-consensus/src/transaction/check.rs
@@ -68,10 +68,10 @@ pub fn has_inputs_and_outputs(tx: &Transaction) -> Result<(), TransactionError>
                 Ok(())
             }
         }
-        Transaction::V1 { .. }
-        | Transaction::V2 { .. }
-        | Transaction::V3 { .. }
-        | Transaction::V5 { .. } => {
+        Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+            unreachable!("tx version is checked first")
+        }
+        Transaction::V5 { .. } => {
             unimplemented!("v5 transaction format as specified in ZIP-225")
         }
     }
@@ -114,10 +114,11 @@ pub fn coinbase_tx_no_joinsplit_or_spend(tx: &Transaction) -> Result<(), Transac
 
             Transaction::V4 { .. } => Ok(()),
 
-            Transaction::V1 { .. }
-            | Transaction::V2 { .. }
-            | Transaction::V3 { .. }
-            | Transaction::V5 { .. } => {
+            Transaction::V1 { .. } | Transaction::V2 { .. } | Transaction::V3 { .. } => {
+                unreachable!("tx version is checked first")
+            }
+
+            Transaction::V5 { .. } => {
                 unimplemented!("v5 coinbase validation as specified in ZIP-225 and the draft spec")
             }
         }

From d5f25197421b08f515effe58be7da914173b88da Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Tue, 2 Mar 2021 19:39:12 -0300
Subject: [PATCH 23/29] change transaction fields order

---
 zebra-chain/src/transaction.rs           |  9 ++++-----
 zebra-chain/src/transaction/serialize.rs | 16 ++++++++--------
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index f8c076db453..ea6c271524f 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -101,16 +101,15 @@ pub enum Transaction {
     },
     /// A `version = 5` transaction, which supports `Sapling` and `Orchard`.
     V5 {
-        /// The transparent inputs to the transaction.
-        inputs: Vec<transparent::Input>,
-        /// The transparent outputs from the transaction.
-        outputs: Vec<transparent::Output>,
         /// The earliest time or block height that this transaction can be added to the
         /// chain.
         lock_time: LockTime,
         /// The latest block height that this transaction can be added to the chain.
         expiry_height: block::Height,
-
+        /// The transparent inputs to the transaction.
+        inputs: Vec<transparent::Input>,
+        /// The transparent outputs from the transaction.
+        outputs: Vec<transparent::Output>,
         /// The rest of the transaction as bytes
         rest: Vec<u8>,
     },
diff --git a/zebra-chain/src/transaction/serialize.rs b/zebra-chain/src/transaction/serialize.rs
index 3beb04d0ed5..742da3ba2c6 100644
--- a/zebra-chain/src/transaction/serialize.rs
+++ b/zebra-chain/src/transaction/serialize.rs
@@ -181,19 +181,19 @@ impl ZcashSerialize for Transaction {
                 }
             }
             Transaction::V5 {
-                inputs,
-                outputs,
                 lock_time,
                 expiry_height,
+                inputs,
+                outputs,
                 rest,
             } => {
                 // Write version 5 and set the fOverwintered bit.
                 writer.write_u32::<LittleEndian>(5 | (1 << 31))?;
                 writer.write_u32::<LittleEndian>(TX_V5_VERSION_GROUP_ID)?;
-                inputs.zcash_serialize(&mut writer)?;
-                outputs.zcash_serialize(&mut writer)?;
                 lock_time.zcash_serialize(&mut writer)?;
                 writer.write_u32::<LittleEndian>(expiry_height.0)?;
+                inputs.zcash_serialize(&mut writer)?;
+                outputs.zcash_serialize(&mut writer)?;
                 // write the rest
                 writer.write_all(rest)?;
             }
@@ -305,18 +305,18 @@ impl ZcashDeserialize for Transaction {
                 if id != TX_V5_VERSION_GROUP_ID {
                     return Err(SerializationError::Parse("expected TX_V5_VERSION_GROUP_ID"));
                 }
-                let inputs = Vec::zcash_deserialize(&mut reader)?;
-                let outputs = Vec::zcash_deserialize(&mut reader)?;
                 let lock_time = LockTime::zcash_deserialize(&mut reader)?;
                 let expiry_height = block::Height(reader.read_u32::<LittleEndian>()?);
+                let inputs = Vec::zcash_deserialize(&mut reader)?;
+                let outputs = Vec::zcash_deserialize(&mut reader)?;
                 let mut rest = Vec::new();
                 reader.read_to_end(&mut rest)?;
 
                 Ok(Transaction::V5 {
-                    inputs,
-                    outputs,
                     lock_time,
                     expiry_height,
+                    inputs,
+                    outputs,
                     rest,
                 })
             }

From 510b571eb1d7202283a7634f344518cf70938a90 Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Tue, 2 Mar 2021 20:03:45 -0300
Subject: [PATCH 24/29] fix unblocked NU5 strategy

---
 zebra-chain/src/transaction/arbitrary.rs | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/zebra-chain/src/transaction/arbitrary.rs b/zebra-chain/src/transaction/arbitrary.rs
index a79fda2f859..33ce6e090f9 100644
--- a/zebra-chain/src/transaction/arbitrary.rs
+++ b/zebra-chain/src/transaction/arbitrary.rs
@@ -255,13 +255,12 @@ impl Arbitrary for Transaction {
             NetworkUpgrade::Sapling => Self::v3_strategy(ledger_state),
             NetworkUpgrade::Blossom | NetworkUpgrade::Heartwood | NetworkUpgrade::Canopy => {
                 Self::v4_strategy(ledger_state)
-            } // Blocked by #1823 and #1824, see #1826
-              /*
-              NetworkUpgrade::NU5 => prop_oneof!(
-                  Self::v4_strategy(ledger_state),
-                  Self::v5_strategy(ledger_state)
-              ),
-              */
+            }
+            NetworkUpgrade::NU5 => prop_oneof![
+                Self::v4_strategy(ledger_state),
+                Self::v5_strategy(ledger_state)
+            ]
+            .boxed(),
         }
     }
 

From 21b85a33f715408c04f8c4b314516d10fa1e7b6f Mon Sep 17 00:00:00 2001
From: Alfredo Garcia <oxarbitrage@gmail.com>
Date: Tue, 2 Mar 2021 21:40:47 -0300
Subject: [PATCH 25/29] change fields order in arbitrary

---
 zebra-chain/src/transaction/arbitrary.rs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/zebra-chain/src/transaction/arbitrary.rs b/zebra-chain/src/transaction/arbitrary.rs
index 33ce6e090f9..80950803fbe 100644
--- a/zebra-chain/src/transaction/arbitrary.rs
+++ b/zebra-chain/src/transaction/arbitrary.rs
@@ -107,18 +107,18 @@ impl Transaction {
     /// Generate a proptest strategy for V5 Transactions
     pub fn v5_strategy(ledger_state: LedgerState) -> BoxedStrategy<Self> {
         (
-            transparent::Input::vec_strategy(ledger_state, 10),
-            vec(any::<transparent::Output>(), 0..10),
             any::<LockTime>(),
             any::<block::Height>(),
+            transparent::Input::vec_strategy(ledger_state, 10),
+            vec(any::<transparent::Output>(), 0..10),
             any::<Vec<u8>>(),
         )
             .prop_map(
-                |(inputs, outputs, lock_time, expiry_height, rest)| Transaction::V5 {
-                    inputs,
-                    outputs,
+                |(lock_time, expiry_height, inputs, outputs, rest)| Transaction::V5 {
                     lock_time,
                     expiry_height,
+                    inputs,
+                    outputs,
                     rest,
                 },
             )

From 9de491fdf7e48d70803b5aaf2595a49b2961af91 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Wed, 3 Mar 2021 16:41:50 +1000
Subject: [PATCH 26/29] We're still deciding if v5 transactions support Sprout

---
 zebra-chain/src/transaction.rs | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index ea6c271524f..f9e6b304390 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -100,6 +100,8 @@ pub enum Transaction {
         shielded_data: Option<ShieldedData>,
     },
     /// A `version = 5` transaction, which supports `Sapling` and `Orchard`.
+    // TODO: does this transaction type support `Sprout`?
+    // Check for ZIP-225 updates after the decision on 2021-03-05.
     V5 {
         /// The earliest time or block height that this transaction can be added to the
         /// chain.
@@ -192,6 +194,12 @@ impl Transaction {
                     .joinsplits()
                     .flat_map(|joinsplit| joinsplit.nullifiers.iter()),
             ),
+            // Maybe JoinSplits, maybe not, we're still deciding
+            Transaction::V5 { .. } => {
+                unimplemented!(
+                    "v5 transaction format as specified in ZIP-225 after decision on 2021-03-05"
+                )
+            }
             // No JoinSplits
             Transaction::V1 { .. }
             | Transaction::V2 {
@@ -205,8 +213,7 @@ impl Transaction {
             | Transaction::V4 {
                 joinsplit_data: None,
                 ..
-            }
-            | Transaction::V5 { .. } => Box::new(std::iter::empty()),
+            } => Box::new(std::iter::empty()),
         }
     }
 

From 433626c426f9e5a4253f2d1c4682f5119a15f2d7 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Wed, 3 Mar 2021 16:42:35 +1000
Subject: [PATCH 27/29] Minor log and comment tweaks

---
 zebra-chain/src/transaction/sighash.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index b63d2688681..b8cc9ea345b 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -246,7 +246,7 @@ impl<'a> SigHasher<'a> {
             Transaction::V3 { joinsplit_data, .. } => joinsplit_data.is_some(),
             Transaction::V4 { joinsplit_data, .. } => joinsplit_data.is_some(),
             Transaction::V5 { .. } => {
-                unimplemented!("v5 transaction format as specified in ZIP-225")
+                unimplemented!("v5 transaction hash as specified in ZIP-225 and ZIP-244")
             }
         };
 
@@ -261,7 +261,7 @@ impl<'a> SigHasher<'a> {
 
         // This code, and the check above for has_joinsplits cannot be combined
         // into a single branch because the `joinsplit_data` type of each
-        // tranaction kind has a different type.
+        // transaction kind has a different type.
         //
         // For v3 joinsplit_data is a JoinSplitData<Bctv14Proof>
         // For v4 joinsplit_data is a JoinSplitData<Groth16Proof>
@@ -269,6 +269,8 @@ impl<'a> SigHasher<'a> {
         // The type parameter on these types prevents them from being unified,
         // which forces us to duplicate the logic in each branch even though the
         // code within each branch is identical.
+        //
+        // TODO: use a generic function to remove the duplicate code
         match self.trans {
             Transaction::V3 {
                 joinsplit_data: Some(jsd),

From 48fb77e69e35b17c54dc92f14531f358f44a8db9 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Wed, 3 Mar 2021 16:42:51 +1000
Subject: [PATCH 28/29] Add a missing V5 transaction match case

---
 zebra-chain/src/transaction/sighash.rs | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/zebra-chain/src/transaction/sighash.rs b/zebra-chain/src/transaction/sighash.rs
index b8cc9ea345b..2b7544b5478 100644
--- a/zebra-chain/src/transaction/sighash.rs
+++ b/zebra-chain/src/transaction/sighash.rs
@@ -290,7 +290,20 @@ impl<'a> SigHasher<'a> {
                 }
                 (&mut hash).write_all(&<[u8; 32]>::from(jsd.pub_key)[..])?;
             }
-            _ => unreachable!("already checked transaction kind above"),
+            Transaction::V5 { .. } => {
+                unimplemented!("v5 transaction hash as specified in ZIP-225 and ZIP-244")
+            }
+
+            Transaction::V1 { .. }
+            | Transaction::V2 { .. }
+            | Transaction::V3 {
+                joinsplit_data: None,
+                ..
+            }
+            | Transaction::V4 {
+                joinsplit_data: None,
+                ..
+            } => unreachable!("already checked transaction kind above"),
         };
 
         writer.write_all(hash.finalize().as_ref())

From 04c7def7ee6f6d4e18876b390a53415fa338bd05 Mon Sep 17 00:00:00 2001
From: teor <teor@riseup.net>
Date: Thu, 4 Mar 2021 07:54:25 +1000
Subject: [PATCH 29/29] Fix decision date

---
 zebra-chain/src/transaction.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/zebra-chain/src/transaction.rs b/zebra-chain/src/transaction.rs
index f9e6b304390..4f2c1285bab 100644
--- a/zebra-chain/src/transaction.rs
+++ b/zebra-chain/src/transaction.rs
@@ -197,7 +197,7 @@ impl Transaction {
             // Maybe JoinSplits, maybe not, we're still deciding
             Transaction::V5 { .. } => {
                 unimplemented!(
-                    "v5 transaction format as specified in ZIP-225 after decision on 2021-03-05"
+                    "v5 transaction format as specified in ZIP-225 after decision on 2021-03-12"
                 )
             }
             // No JoinSplits