From 989f68bd38052c15d8cb1485d80eb1b764cbecae Mon Sep 17 00:00:00 2001
From: Chris Smith <chris@walletconnect.com>
Date: Sat, 27 Apr 2024 20:26:07 -0400
Subject: [PATCH] fix: use Alloy address recovery

---
 relay_rpc/Cargo.toml                         |  3 +-
 relay_rpc/src/auth/cacao/signature/eip191.rs | 34 ++++++--------------
 relay_rpc/src/auth/cacao/signature/mod.rs    |  4 +--
 3 files changed, 12 insertions(+), 29 deletions(-)

diff --git a/relay_rpc/Cargo.toml b/relay_rpc/Cargo.toml
index 677a92a..0473b69 100644
--- a/relay_rpc/Cargo.toml
+++ b/relay_rpc/Cargo.toml
@@ -7,7 +7,6 @@ license = "Apache-2.0"
 [features]
 default = ["cacao"]
 cacao = [
-    "dep:k256",
     "dep:alloy-provider",
     "dep:alloy-primitives",
     "dep:erc6492",
@@ -35,7 +34,6 @@ chrono = { version = "0.4", default-features = false, features = [
 regex = "1.7"
 once_cell = "1.16"
 jsonwebtoken = "8.1"
-k256 = { version = "0.13", optional = true }
 sha2 = { version = "0.10.6" }
 url = "2"
 alloy-provider = { git = "https://github.com/alloy-rs/alloy.git", rev = "d68a6b7", optional = true }
@@ -44,6 +42,7 @@ erc6492 = { git = "https://github.com/WalletConnect/erc6492.git", optional = tru
 strum = { version = "0.26", features = ["strum_macros", "derive"] }
 
 [dev-dependencies]
+k256 = "0.13"
 tokio = { version = "1.35.1", features = ["test-util", "macros"] }
 
 [lints.clippy]
diff --git a/relay_rpc/src/auth/cacao/signature/eip191.rs b/relay_rpc/src/auth/cacao/signature/eip191.rs
index 33ad441..7fec4fa 100644
--- a/relay_rpc/src/auth/cacao/signature/eip191.rs
+++ b/relay_rpc/src/auth/cacao/signature/eip191.rs
@@ -1,36 +1,20 @@
 use {
     super::CacaoError,
-    alloy_primitives::{Address, FixedBytes},
+    alloy_primitives::{Address, Signature},
 };
 
 pub const EIP191: &str = "eip191";
 
-pub fn eip191_bytes(message: &str) -> Vec<u8> {
-    format!(
-        "\u{0019}Ethereum Signed Message:\n{}{}",
-        message.as_bytes().len(),
-        message
-    )
-    .into()
-}
-
 pub fn verify_eip191(
     signature: &[u8],
     address: &Address,
-    hash: FixedBytes<32>,
+    message: &[u8],
 ) -> Result<(), CacaoError> {
-    use k256::ecdsa::{RecoveryId, Signature as Sig, VerifyingKey};
-
-    let sig = Sig::try_from(signature.get(..64).ok_or(CacaoError::Verification)?)
-        .map_err(|_| CacaoError::Verification)?;
-    let recovery_id = RecoveryId::try_from(signature.get(64).ok_or(CacaoError::Verification)? % 27)
+    let signature = Signature::try_from(signature).map_err(|_| CacaoError::Verification)?;
+    let add = signature
+        .recover_address_from_msg(message)
         .map_err(|_| CacaoError::Verification)?;
 
-    let recovered_key = VerifyingKey::recover_from_prehash(hash.as_slice(), &sig, recovery_id)
-        .map_err(|_| CacaoError::Verification)?;
-
-    let add = Address::from_public_key(&recovered_key);
-
     if &add == address {
         Ok(())
     } else {
@@ -61,7 +45,7 @@ mod tests {
         let message = "xxx";
         let signature = sign_message(message, &private_key);
         let address = Address::from_private_key(&private_key);
-        verify_eip191(&signature, &address, eip191_hash_message(message)).unwrap();
+        verify_eip191(&signature, &address, message.as_bytes()).unwrap();
     }
 
     #[test]
@@ -71,7 +55,7 @@ mod tests {
         let mut signature = sign_message(message, &private_key);
         *signature.first_mut().unwrap() = signature.first().unwrap().wrapping_add(1);
         let address = Address::from_private_key(&private_key);
-        assert!(verify_eip191(&signature, &address, eip191_hash_message(message)).is_err());
+        assert!(verify_eip191(&signature, &address, message.as_bytes()).is_err());
     }
 
     #[test]
@@ -81,7 +65,7 @@ mod tests {
         let signature = sign_message(message, &private_key);
         let mut address = Address::from_private_key(&private_key);
         *address.0.first_mut().unwrap() = address.0.first().unwrap().wrapping_add(1);
-        assert!(verify_eip191(&signature, &address, eip191_hash_message(message)).is_err());
+        assert!(verify_eip191(&signature, &address, message.as_bytes()).is_err());
     }
 
     #[test]
@@ -91,6 +75,6 @@ mod tests {
         let signature = sign_message(message, &private_key);
         let address = Address::from_private_key(&private_key);
         let message2 = "yyy";
-        assert!(verify_eip191(&signature, &address, eip191_hash_message(message2)).is_err());
+        assert!(verify_eip191(&signature, &address, message2.as_bytes()).is_err());
     }
 }
diff --git a/relay_rpc/src/auth/cacao/signature/mod.rs b/relay_rpc/src/auth/cacao/signature/mod.rs
index 9b133b6..c04b077 100644
--- a/relay_rpc/src/auth/cacao/signature/mod.rs
+++ b/relay_rpc/src/auth/cacao/signature/mod.rs
@@ -4,7 +4,7 @@ use {
         get_rpc_url::GetRpcUrl,
     },
     super::{Cacao, CacaoError},
-    alloy_primitives::{eip191_hash_message, hex::FromHex, Address, Bytes},
+    alloy_primitives::{hex::FromHex, Address, Bytes},
     alloy_provider::{network::Ethereum, ReqwestProvider},
     erc6492::verify_signature,
     serde::{Deserialize, Serialize},
@@ -39,7 +39,7 @@ impl Signature {
             EIP191 => {
                 // Technically we can use EIP-6492 to verify EIP-191 signatures as well,
                 // but since we know the signature type we can avoid an RPC request.
-                verify_eip191(&signature, &address, eip191_hash_message(message))
+                verify_eip191(&signature, &address, message.as_bytes())
             }
             EIP1271 | EIP6492 => {
                 if let Some(provider) = provider {