From 75573d331a83dc2b78b302c9e0b85cb07570b4b1 Mon Sep 17 00:00:00 2001
From: Kris Nuttycombe <kris@electriccoin.co>
Date: Fri, 23 Apr 2021 12:53:13 -0600
Subject: [PATCH] Add canonical byte conversions for value commitments.

---
 src/bundle.rs |  2 +-
 src/value.rs  | 13 ++++++++++++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/bundle.rs b/src/bundle.rs
index 9489d578..55834c45 100644
--- a/src/bundle.rs
+++ b/src/bundle.rs
@@ -7,7 +7,7 @@ use crate::{
     note::{ExtractedNoteCommitment, Nullifier, TransmittedNoteCiphertext},
     primitives::redpallas::{self, Binding, SpendAuth},
     tree::Anchor,
-    value::{ValueCommitment},
+    value::ValueCommitment,
 };
 
 /// An action applied to the global ledger.
diff --git a/src/value.rs b/src/value.rs
index 08c35fe2..20b9f1c8 100644
--- a/src/value.rs
+++ b/src/value.rs
@@ -14,7 +14,7 @@
 //! [`Action`]: crate::bundle::Action
 //! [`Bundle`]: crate::bundle::Bundle
 
-use std::convert::{TryInto, TryFrom};
+use std::convert::{TryFrom, TryInto};
 use std::fmt::{self, Debug};
 use std::iter::Sum;
 use std::ops::{Add, Sub};
@@ -27,6 +27,7 @@ use pasta_curves::{
     pallas,
 };
 use rand::RngCore;
+use subtle::CtOption;
 
 use crate::primitives::redpallas::{self, Binding};
 
@@ -214,6 +215,16 @@ impl ValueCommitment {
         // TODO: impl From<pallas::Point> for redpallas::VerificationKey.
         self.0.to_bytes().try_into().unwrap()
     }
+
+    /// Deserialize a value commitment from its byte representation
+    pub fn from_bytes(bytes: &[u8; 32]) -> CtOption<ValueCommitment> {
+        pallas::Point::from_bytes(bytes).map(ValueCommitment)
+    }
+
+    /// Serialize this value commitment to its canonical byte representation.
+    pub fn to_bytes(&self) -> [u8; 32] {
+        self.0.to_bytes()
+    }
 }
 
 #[cfg(test)]