From a8003c8ff52973dc506a9a0f05d37f39753256b6 Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@electriccoin.co>
Date: Wed, 8 Mar 2023 03:45:01 +0000
Subject: [PATCH] Temporarily re-expose ability to construct invalid Sapling
 bundles

Until zcash/zcash#6397 is closed, this ability is needed by `zcashd` for
crossing the FFI.
---
 zcash_primitives/CHANGELOG.md                 | 10 +++
 zcash_primitives/Cargo.toml                   |  3 +-
 .../src/transaction/components/sapling.rs     | 62 ++++++++++++++++++-
 3 files changed, 71 insertions(+), 4 deletions(-)

diff --git a/zcash_primitives/CHANGELOG.md b/zcash_primitives/CHANGELOG.md
index 0dcaa7fbe..b017d7909 100644
--- a/zcash_primitives/CHANGELOG.md
+++ b/zcash_primitives/CHANGELOG.md
@@ -7,6 +7,16 @@ and this library adheres to Rust's notion of
 
 ## [Unreleased]
 
+## [0.10.1] - 2023-03-08
+### Added
+- Sapling bundle component constructors, behind the `temporary-zcashd` feature
+  flag. These temporarily re-expose the ability to construct invalid Sapling
+  bundles (that was removed in 0.10.0), and will be removed in a future release:
+  - `zcash_primitives::transaction::components::sapling`:
+    - `Bundle::temporary_zcashd_from_parts`
+    - `SpendDescription::temporary_zcashd_from_parts`
+    - `OutputDescription::temporary_zcashd_from_parts`
+
 ## [0.10.0] - 2023-02-01
 ### Added
 - `zcash_primitives::sapling`:
diff --git a/zcash_primitives/Cargo.toml b/zcash_primitives/Cargo.toml
index bda15d5fb..d0e7e8e38 100644
--- a/zcash_primitives/Cargo.toml
+++ b/zcash_primitives/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "zcash_primitives"
 description = "Rust implementations of the Zcash primitives"
-version = "0.10.0"
+version = "0.10.1"
 authors = [
     "Jack Grigg <jack@z.cash>",
     "Kris Nuttycombe <kris@electriccoin.co>"
@@ -98,6 +98,7 @@ inferno = ">=0.11, <0.11.5" # MSRV 1.59
 
 [features]
 transparent-inputs = ["hdwallet", "ripemd", "secp256k1"]
+temporary-zcashd = []
 test-dependencies = ["proptest", "orchard/test-dependencies"]
 zfuture = []
 
diff --git a/zcash_primitives/src/transaction/components/sapling.rs b/zcash_primitives/src/transaction/components/sapling.rs
index 7730098e4..dc1b66380 100644
--- a/zcash_primitives/src/transaction/components/sapling.rs
+++ b/zcash_primitives/src/transaction/components/sapling.rs
@@ -105,6 +105,22 @@ pub struct Bundle<A: Authorization> {
 }
 
 impl<A: Authorization> Bundle<A> {
+    /// Constructs a `Bundle` from its constituent parts.
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_from_parts(
+        shielded_spends: Vec<SpendDescription<A>>,
+        shielded_outputs: Vec<OutputDescription<A::OutputProof>>,
+        value_balance: Amount,
+        authorization: A,
+    ) -> Self {
+        Self::from_parts(
+            shielded_spends,
+            shielded_outputs,
+            value_balance,
+            authorization,
+        )
+    }
+
     /// Constructs a `Bundle` from its constituent parts.
     pub(crate) fn from_parts(
         shielded_spends: Vec<SpendDescription<A>>,
@@ -197,6 +213,25 @@ impl<A: Authorization> std::fmt::Debug for SpendDescription<A> {
 }
 
 impl<A: Authorization> SpendDescription<A> {
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_from_parts(
+        cv: ValueCommitment,
+        anchor: bls12_381::Scalar,
+        nullifier: Nullifier,
+        rk: PublicKey,
+        zkproof: A::SpendProof,
+        spend_auth_sig: A::AuthSig,
+    ) -> Self {
+        Self {
+            cv,
+            anchor,
+            nullifier,
+            rk,
+            zkproof,
+            spend_auth_sig,
+        }
+    }
+
     /// Returns the commitment to the value consumed by this spend.
     pub fn cv(&self) -> &ValueCommitment {
         &self.cv
@@ -410,10 +445,27 @@ impl<Proof> OutputDescription<Proof> {
     pub fn zkproof(&self) -> &Proof {
         &self.zkproof
     }
-}
 
-#[cfg(test)]
-impl<Proof> OutputDescription<Proof> {
+    #[cfg(feature = "temporary-zcashd")]
+    pub fn temporary_zcashd_from_parts(
+        cv: ValueCommitment,
+        cmu: ExtractedNoteCommitment,
+        ephemeral_key: EphemeralKeyBytes,
+        enc_ciphertext: [u8; 580],
+        out_ciphertext: [u8; 80],
+        zkproof: Proof,
+    ) -> Self {
+        Self::from_parts(
+            cv,
+            cmu,
+            ephemeral_key,
+            enc_ciphertext,
+            out_ciphertext,
+            zkproof,
+        )
+    }
+
+    #[cfg(any(test, feature = "temporary-zcashd"))]
     pub(crate) fn from_parts(
         cv: ValueCommitment,
         cmu: ExtractedNoteCommitment,
@@ -431,6 +483,10 @@ impl<Proof> OutputDescription<Proof> {
             zkproof,
         }
     }
+}
+
+#[cfg(test)]
+impl<Proof> OutputDescription<Proof> {
     pub(crate) fn cv_mut(&mut self) -> &mut ValueCommitment {
         &mut self.cv
     }