From 91ea65f6af7039095c7a3af7bc1e4ce302a68a8d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81lvaro=20Rodr=C3=ADguez?= <sirasistant@gmail.com>
Date: Wed, 31 May 2023 16:28:50 +0200
Subject: [PATCH] feat!: added keccakvar constraints (#213)

feat: added keccakvar constraints
---
 flake.lock                     |  6 ++---
 src/barretenberg_structures.rs | 40 ++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/flake.lock b/flake.lock
index cbf59563..dff81844 100644
--- a/flake.lock
+++ b/flake.lock
@@ -10,11 +10,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1685019724,
-        "narHash": "sha256-QWsYyrOda1u0qAQVifybjdibeP6NCWzk4cJ2mtrzA2E=",
+        "lastModified": 1685045859,
+        "narHash": "sha256-AdR8z8z/6JZDvyiaMCfHZ+JA5VQw5KhlAeiaytO6sns=",
         "owner": "AztecProtocol",
         "repo": "barretenberg",
-        "rev": "ad282152836f5e3a5c8f34256b29bdea9d16b854",
+        "rev": "083479164411be9cf9642e755182f059c9415a53",
         "type": "github"
       },
       "original": {
diff --git a/src/barretenberg_structures.rs b/src/barretenberg_structures.rs
index 55ca562a..3ffb37ea 100644
--- a/src/barretenberg_structures.rs
+++ b/src/barretenberg_structures.rs
@@ -337,6 +337,36 @@ impl Keccak256Constraint {
     }
 }
 
+#[derive(Clone, Hash, Debug, Serialize, Deserialize)]
+pub(crate) struct Keccak256VarConstraint {
+    pub(crate) inputs: Vec<(i32, i32)>,
+    pub(crate) result: [i32; 32],
+    pub(crate) var_message_size: i32,
+}
+
+impl Keccak256VarConstraint {
+    fn to_bytes(&self) -> Vec<u8> {
+        let mut buffer = Vec::new();
+
+        let inputs_len = self.inputs.len() as u32;
+        buffer.extend_from_slice(&inputs_len.to_be_bytes());
+        for constraint in self.inputs.iter() {
+            buffer.extend_from_slice(&constraint.0.to_be_bytes());
+            buffer.extend_from_slice(&constraint.1.to_be_bytes());
+        }
+
+        let result_len = self.result.len() as u32;
+        buffer.extend_from_slice(&result_len.to_be_bytes());
+        for constraint in self.result.iter() {
+            buffer.extend_from_slice(&constraint.to_be_bytes());
+        }
+
+        buffer.extend_from_slice(&self.var_message_size.to_be_bytes());
+
+        buffer
+    }
+}
+
 #[derive(Clone, Hash, Debug, Serialize, Deserialize)]
 pub(crate) struct PedersenConstraint {
     pub(crate) inputs: Vec<i32>,
@@ -435,6 +465,7 @@ pub(crate) struct ConstraintSystem {
     blake2s_constraints: Vec<Blake2sConstraint>,
     block_constraints: Vec<BlockConstraint>,
     keccak_constraints: Vec<Keccak256Constraint>,
+    keccak_var_constraints: Vec<Keccak256VarConstraint>,
     pedersen_constraints: Vec<PedersenConstraint>,
     hash_to_field_constraints: Vec<HashToFieldConstraint>,
     fixed_base_scalar_mul_constraints: Vec<FixedBaseScalarMulConstraint>,
@@ -626,6 +657,13 @@ impl ConstraintSystem {
             buffer.extend(&constraint.to_bytes());
         }
 
+        // Serialize each Keccak Var constraint
+        let keccak_var_len = self.keccak_var_constraints.len() as u32;
+        buffer.extend_from_slice(&keccak_var_len.to_be_bytes());
+        for constraint in self.keccak_var_constraints.iter() {
+            buffer.extend(&constraint.to_bytes());
+        }
+
         // Serialize each Pedersen constraint
         let pedersen_len = self.pedersen_constraints.len() as u32;
         buffer.extend_from_slice(&pedersen_len.to_be_bytes());
@@ -749,6 +787,7 @@ impl TryFrom<&Circuit> for ConstraintSystem {
         let mut blake2s_constraints: Vec<Blake2sConstraint> = Vec::new();
         let mut block_constraints: Vec<BlockConstraint> = Vec::new();
         let mut keccak_constraints: Vec<Keccak256Constraint> = Vec::new();
+        let keccak_var_constraints: Vec<Keccak256VarConstraint> = Vec::new();
         let mut pedersen_constraints: Vec<PedersenConstraint> = Vec::new();
         let mut compute_merkle_root_constraints: Vec<ComputeMerkleRootConstraint> = Vec::new();
         let mut schnorr_constraints: Vec<SchnorrConstraint> = Vec::new();
@@ -1126,6 +1165,7 @@ impl TryFrom<&Circuit> for ConstraintSystem {
             blake2s_constraints,
             block_constraints,
             keccak_constraints,
+            keccak_var_constraints,
             hash_to_field_constraints,
             constraints,
             fixed_base_scalar_mul_constraints,