From 53c8645ac859feeade5e505582d8fb70e71c3274 Mon Sep 17 00:00:00 2001
From: Mathieu <60658558+enitrat@users.noreply.github.com>
Date: Fri, 13 Sep 2024 12:07:18 +0200
Subject: [PATCH] fix: signature y parity deserialization (#934)

---
 crates/utils/src/serialization.cairo          | 29 +++++++++++++++++--
 scripts/compute_rlp_encoding.ts               | 11 ++++++-
 .../data/input_eip1559_y_parity_false.json    | 11 +++++++
 3 files changed, 47 insertions(+), 4 deletions(-)
 create mode 100644 scripts/data/input_eip1559_y_parity_false.json

diff --git a/crates/utils/src/serialization.cairo b/crates/utils/src/serialization.cairo
index c29b2f9f2..58c17b910 100644
--- a/crates/utils/src/serialization.cairo
+++ b/crates/utils/src/serialization.cairo
@@ -11,7 +11,9 @@ pub fn deserialize_signature(signature: Span<felt252>, chain_id: u64) -> Option<
 
     let v: u128 = (*signature.at(4)).try_into()?;
 
-    let y_parity = if (v == 0 || v == 1) {
+    let odd_y_parity = if v == 0 {
+        false
+    } else if v == 1 {
         true
     } else {
         compute_y_parity(v, chain_id)?
@@ -19,7 +21,9 @@ pub fn deserialize_signature(signature: Span<felt252>, chain_id: u64) -> Option<
 
     Option::Some(
         Signature {
-            r: u256 { low: r_low, high: r_high }, s: u256 { low: s_low, high: s_high }, y_parity,
+            r: u256 { low: r_low, high: r_high },
+            s: u256 { low: s_low, high: s_high },
+            y_parity: odd_y_parity,
         }
     )
 }
@@ -196,6 +200,13 @@ mod tests {
             y_parity: true
         };
 
+        // tx_type = 2 with false y parity - cf input_eip1559_y_parity_false.json
+        let signature_3 = Signature {
+            r: 0x782ce82b688abbf13a5e7536b27be67d2795a28b9d4bf819120c17630d88e609,
+            s: 0x43b90a3315977fe71c9b3687a89857544158e23c5045e7a5852bae03323c9898,
+            y_parity: false
+        };
+
         let signature_0_felt252_arr: Array<felt252> = array![
             signature_0.r.low.into(),
             signature_0.r.high.into(),
@@ -209,7 +220,7 @@ mod tests {
             signature_1.r.high.into(),
             signature_1.s.low.into(),
             signature_1.s.high.into(),
-            0x0
+            0x1
         ];
 
         let signature_2_felt252_arr: Array<felt252> = array![
@@ -217,6 +228,14 @@ mod tests {
             signature_2.r.high.into(),
             signature_2.s.low.into(),
             signature_2.s.high.into(),
+            0x1
+        ];
+
+        let signature_3_felt252_arr: Array<felt252> = array![
+            signature_3.r.low.into(),
+            signature_3.r.high.into(),
+            signature_3.s.low.into(),
+            signature_3.s.high.into(),
             0x0
         ];
 
@@ -231,5 +250,9 @@ mod tests {
         let result: Signature = deserialize_signature(signature_2_felt252_arr.span(), CHAIN_ID)
             .unwrap();
         assert_eq!(result, signature_2);
+
+        let result: Signature = deserialize_signature(signature_3_felt252_arr.span(), CHAIN_ID)
+            .unwrap();
+        assert_eq!(result, signature_3);
     }
 }
diff --git a/scripts/compute_rlp_encoding.ts b/scripts/compute_rlp_encoding.ts
index a9d00be58..692922397 100644
--- a/scripts/compute_rlp_encoding.ts
+++ b/scripts/compute_rlp_encoding.ts
@@ -36,7 +36,7 @@ const main = async () => {
 
   let tx_type = parseInt(
     await question(
-      "enter transaction, 0: legacy, 1: 2930, 2:1559, 3: inc_counter ",
+      "enter transaction, 0: legacy, 1: 2930, 2:1559, 3: inc_counter, 4: y_parity_false eip1559: ",
     ),
   );
 
@@ -68,6 +68,15 @@ const main = async () => {
         ),
       );
       break;
+    case 4:
+      tx_type = 2;
+      tx = JSON.parse(
+        readFileSync(
+          "./scripts/data/input_eip1559_y_parity_false.json",
+          "utf-8",
+        ),
+      );
+      break;
     default:
       throw new Error(
         `transaction type ${tx_type} isn't a valid transaction type`,
diff --git a/scripts/data/input_eip1559_y_parity_false.json b/scripts/data/input_eip1559_y_parity_false.json
new file mode 100644
index 000000000..16ac42ade
--- /dev/null
+++ b/scripts/data/input_eip1559_y_parity_false.json
@@ -0,0 +1,11 @@
+{
+  "nonce": "0x1",
+  "maxPriorityFeePerGas": "0x64",
+  "maxFeePerGas": "0x3e8",
+  "gasLimit": "0x64c9",
+  "to": "0xcccccccccccccccccccccccccccccccccccccccc",
+  "value": "0x0",
+  "data": "0x00",
+  "accessList": [],
+  "chainId": "0x4b4b5254"
+}