From f2fb3616315f6c30fb5f354e9b3147d581c9d8d2 Mon Sep 17 00:00:00 2001
From: Rodrigo Quelhas <rodrigo_quelhas@outlook.pt>
Date: Thu, 23 May 2024 11:44:10 +0100
Subject: [PATCH] add MockSignature and MockSigner to precompile test utils

---
 precompiles/src/testing/account.rs | 88 ++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/precompiles/src/testing/account.rs b/precompiles/src/testing/account.rs
index ad83047713..77aa0f6c7b 100644
--- a/precompiles/src/testing/account.rs
+++ b/precompiles/src/testing/account.rs
@@ -100,6 +100,94 @@ impl sp_runtime::traits::Convert<H160, MockAccount> for MockAccount {
 	}
 }
 
+#[derive(
+	Eq,
+	PartialEq,
+	Clone,
+	Encode,
+	Decode,
+	sp_core::RuntimeDebug,
+	TypeInfo,
+	Serialize,
+	Deserialize
+)]
+pub struct MockSignature(sp_core::ecdsa::Signature);
+
+impl From<sp_core::ecdsa::Signature> for MockSignature {
+	fn from(x: sp_core::ecdsa::Signature) -> Self {
+		MockSignature(x)
+	}
+}
+
+impl From<sp_runtime::MultiSignature> for MockSignature {
+	fn from(signature: sp_runtime::MultiSignature) -> Self {
+		match signature {
+			sp_runtime::MultiSignature::Ed25519(_) => {
+				panic!("Ed25519 not supported for MockSignature")
+			}
+			sp_runtime::MultiSignature::Sr25519(_) => {
+				panic!("Sr25519 not supported for MockSignature")
+			}
+			sp_runtime::MultiSignature::Ecdsa(sig) => Self(sig),
+		}
+	}
+}
+
+impl sp_runtime::traits::Verify for MockSignature {
+	type Signer = MockSigner;
+	fn verify<L: sp_runtime::traits::Lazy<[u8]>>(&self, mut msg: L, signer: &MockAccount) -> bool {
+		let mut m = [0u8; 32];
+		m.copy_from_slice(<sha3::Keccak256 as sha3::Digest>::digest(msg.get()).as_slice());
+		match sp_io::crypto::secp256k1_ecdsa_recover(self.0.as_ref(), &m) {
+			Ok(pubkey) => {
+				MockAccount(sp_core::H160::from_slice(
+					&<sha3::Keccak256 as sha3::Digest>::digest(pubkey).as_slice()[12..32],
+				)) == *signer
+			}
+			Err(sp_io::EcdsaVerifyError::BadRS) => {
+				log::error!(target: "evm", "Error recovering: Incorrect value of R or S");
+				false
+			}
+			Err(sp_io::EcdsaVerifyError::BadV) => {
+				log::error!(target: "evm", "Error recovering: Incorrect value of V");
+				false
+			}
+			Err(sp_io::EcdsaVerifyError::BadSignature) => {
+				log::error!(target: "evm", "Error recovering: Invalid signature");
+				false
+			}
+		}
+	}
+}
+
+/// Public key for an Ethereum compatible account
+#[derive(
+	Eq,
+	PartialEq,
+	Ord,
+	PartialOrd,
+	Clone,
+	Encode,
+	Decode,
+	sp_core::RuntimeDebug,
+	TypeInfo
+)]
+#[cfg_attr(feature = "std", derive(serde::Serialize, serde::Deserialize))]
+pub struct MockSigner([u8; 20]);
+
+impl sp_runtime::traits::IdentifyAccount for MockSigner {
+	type AccountId = MockAccount;
+	fn into_account(self) -> MockAccount {
+		MockAccount(self.0.into())
+	}
+}
+
+impl From<[u8; 20]> for MockSigner {
+	fn from(x: [u8; 20]) -> Self {
+		MockSigner(x)
+	}
+}
+
 #[macro_export]
 macro_rules! mock_account {
 	($name:ident, $convert:expr) => {