From 28b703f9a6730cce98bb4aaf1e8de9772c8356f2 Mon Sep 17 00:00:00 2001
From: Jochem Brouwer <jochembrouwer96@gmail.com>
Date: Sun, 5 May 2024 06:30:39 +0200
Subject: [PATCH] evm: fix bls g1add/g2add

---
 .../evm/src/precompiles/0b-bls12-g1add.ts     |  4 +--
 .../evm/src/precompiles/0e-bls12-g2add.ts     |  4 +--
 .../evm/src/precompiles/util/bls12_381.ts     | 31 +++++++++++++------
 3 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/packages/evm/src/precompiles/0b-bls12-g1add.ts b/packages/evm/src/precompiles/0b-bls12-g1add.ts
index d3e63d1619..060f40418a 100644
--- a/packages/evm/src/precompiles/0b-bls12-g1add.ts
+++ b/packages/evm/src/precompiles/0b-bls12-g1add.ts
@@ -60,8 +60,8 @@ export async function precompile0b(opts: PrecompileInput): Promise<ExecResult> {
   let mclPoint1
   let mclPoint2
   try {
-    mclPoint1 = BLS12_381_ToG1Point(opts.data.subarray(0, 128), mcl)
-    mclPoint2 = BLS12_381_ToG1Point(opts.data.subarray(128, 256), mcl)
+    mclPoint1 = BLS12_381_ToG1Point(opts.data.subarray(0, 128), mcl, false)
+    mclPoint2 = BLS12_381_ToG1Point(opts.data.subarray(128, 256), mcl, false)
   } catch (e: any) {
     if (opts._debug !== undefined) {
       opts._debug(`BLS12G1ADD (0x0b) failed: ${e.message}`)
diff --git a/packages/evm/src/precompiles/0e-bls12-g2add.ts b/packages/evm/src/precompiles/0e-bls12-g2add.ts
index 1694a47399..a86a401f41 100644
--- a/packages/evm/src/precompiles/0e-bls12-g2add.ts
+++ b/packages/evm/src/precompiles/0e-bls12-g2add.ts
@@ -67,8 +67,8 @@ export async function precompile0e(opts: PrecompileInput): Promise<ExecResult> {
   let mclPoint2
 
   try {
-    mclPoint1 = BLS12_381_ToG2Point(opts.data.subarray(0, 256), mcl)
-    mclPoint2 = BLS12_381_ToG2Point(opts.data.subarray(256, 512), mcl)
+    mclPoint1 = BLS12_381_ToG2Point(opts.data.subarray(0, 256), mcl, false)
+    mclPoint2 = BLS12_381_ToG2Point(opts.data.subarray(256, 512), mcl, false)
   } catch (e: any) {
     return EvmErrorResult(e, opts.gasLimit)
   }
diff --git a/packages/evm/src/precompiles/util/bls12_381.ts b/packages/evm/src/precompiles/util/bls12_381.ts
index 7f7e24e941..a882c8c4b6 100644
--- a/packages/evm/src/precompiles/util/bls12_381.ts
+++ b/packages/evm/src/precompiles/util/bls12_381.ts
@@ -145,10 +145,15 @@ export const gasDiscountPairs = [
   [127, 175],
   [128, 174],
 ]
-// convert an input Uint8Array to a mcl G1 point
-// this does /NOT/ do any input checks. the input Uint8Array needs to be of length 128
-// it does raise an error if the point is not on the curve.
-function BLS12_381_ToG1Point(input: Uint8Array, mcl: any): any {
+/**
+ * Converts an Uint8Array to a MCL G1 point. Raises errors if the point is not on the curve
+ * and (if activated) if the point is in the subgroup / order check.
+ * @param input Input Uint8Array. Should be 128 bytes
+ * @param mcl MCL instance
+ * @param verifyOrder Perform the subgroup check (defaults to true)
+ * @returns MCL G1 point
+ */
+function BLS12_381_ToG1Point(input: Uint8Array, mcl: any, verifyOrder = true): any {
   const p_x = bytesToUnprefixedHex(input.subarray(16, 64))
   const p_y = bytesToUnprefixedHex(input.subarray(80, 128))
 
@@ -171,7 +176,8 @@ function BLS12_381_ToG1Point(input: Uint8Array, mcl: any): any {
   G1.setY(Fp_Y)
   G1.setZ(One)
 
-  if (G1.isValidOrder() === false) {
+  mcl.verifyOrderG1(verifyOrder)
+  if (verifyOrder && G1.isValidOrder() === false) {
     throw new EvmError(ERROR.BLS_12_381_POINT_NOT_ON_CURVE)
   }
 
@@ -206,9 +212,15 @@ function BLS12_381_FromG1Point(input: any): Uint8Array {
   return concatBytes(xBuffer, yBuffer)
 }
 
-// convert an input Uint8Array to a mcl G2 point
-// this does /NOT/ do any input checks. the input Uint8Array needs to be of length 256
-function BLS12_381_ToG2Point(input: Uint8Array, mcl: any): any {
+/**
+ * Converts an Uint8Array to a MCL G2 point. Raises errors if the point is not on the curve
+ * and (if activated) if the point is in the subgroup / order check.
+ * @param input Input Uint8Array. Should be 256 bytes
+ * @param mcl MCL instance
+ * @param verifyOrder Perform the subgroup check (defaults to true)
+ * @returns MCL G2 point
+ */
+function BLS12_381_ToG2Point(input: Uint8Array, mcl: any, verifyOrder = true): any {
   const p_x_1 = input.subarray(0, 64)
   const p_x_2 = input.subarray(64, 128)
   const p_y_1 = input.subarray(128, 192)
@@ -245,7 +257,8 @@ function BLS12_381_ToG2Point(input: Uint8Array, mcl: any): any {
   mclPoint.setY(Fp2Y)
   mclPoint.setZ(Fp2One)
 
-  if (mclPoint.isValidOrder() === false) {
+  mcl.verifyOrderG2(verifyOrder)
+  if (verifyOrder && mclPoint.isValidOrder() === false) {
     throw new EvmError(ERROR.BLS_12_381_POINT_NOT_ON_CURVE)
   }