Update mock signer interface

lib/src/signer.rs

@@ -43,10 +43,27 @@ pub struct SignResult {
     pub s_hex: String,
 }
 
+#[near(serializers = [json])]
+pub struct AffnPnt {
+    pub affine_point: String,
+}
+
+#[near(serializers = [json])]
+pub struct Sclr {
+    pub scalar: String,
+}
+
+#[near(serializers = [json])]
+pub struct SignatureResponse {
+    pub big_r: AffnPnt,
+    pub s: Sclr,
+    pub recovery_id: u8,
+}
+
 #[allow(clippy::ptr_arg)]
 #[ext_contract(ext_signer)]
 pub trait SignerInterface {
-    fn sign(&mut self, request: SignRequest) -> PromiseOrValue<SignResult>;
+    fn sign(&mut self, request: SignRequest) -> PromiseOrValue<SignatureResponse>;
     fn public_key(&self) -> near_sdk::PublicKey;
     fn derived_public_key(
         &self,
@@ -115,3 +132,25 @@ impl TryFrom<SignResult> for ethers_core::types::Signature {
         })
     }
 }
+
+impl TryFrom<SignatureResponse> for ethers_core::types::Signature {
+    type Error = SignResultDecodeError;
+
+    fn try_from(signature_response: SignatureResponse) -> Result<Self, Self::Error> {
+        let big_r = Option::<AffinePoint>::from(AffinePoint::from_bytes(
+            hex::decode(signature_response.big_r.affine_point)?[..].into(),
+        ))
+        .ok_or(SignResultDecodeError::InvalidSignatureData)?;
+        let s = hex::decode(signature_response.s.scalar)?;
+
+        let r = <k256::Scalar as Reduce<<Secp256k1 as elliptic_curve::Curve>::Uint>>::reduce_bytes(
+            &big_r.x(),
+        );
+
+        Ok(ethers_core::types::Signature {
+            r: r.to_bytes().as_slice().into(),
+            s: s.as_slice().into(),
+            v: signature_response.recovery_id.into(),
+        })
+    }
+}

mock/signer/src/lib.rs

@@ -1,6 +1,6 @@
 use lib::{
     kdf::sha256,
-    signer::{SignRequest, SignResult, SignerInterface},
+    signer::{AffnPnt, Sclr, SignRequest, SignResult, SignatureResponse, SignerInterface},
     Rejectable,
 };
 use near_sdk::{env, near, require, AccountId, PromiseOrValue, PublicKey};
@@ -23,7 +23,7 @@ pub struct MockSignerContract {}
 #[near]
 impl SignerInterface for MockSignerContract {
     #[payable]
-    fn sign(&mut self, request: SignRequest) -> PromiseOrValue<SignResult> {
+    fn sign(&mut self, request: SignRequest) -> PromiseOrValue<SignatureResponse> {
         require!(
             request.key_version == KEY_VERSION,
             "Key version not supported",
@@ -35,7 +35,22 @@ impl SignerInterface for MockSignerContract {
         let (sig, recid) = signing_key
             .sign_prehash_recoverable(&request.payload)
             .unwrap();
-        PromiseOrValue::Value(SignResult::from_ecdsa_signature(sig, recid).unwrap())
+
+        // Create SignResult from the signature
+        let sign_result = SignResult::from_ecdsa_signature(sig, recid).unwrap();
+
+        // Convert SignResult to SignatureResponse
+        let signature_response = SignatureResponse {
+            big_r: AffnPnt {
+                affine_point: sign_result.big_r_hex,
+            },
+            s: Sclr {
+                scalar: sign_result.s_hex,
+            },
+            recovery_id: recid.to_byte(),
+        };
+
+        PromiseOrValue::Value(signature_response)
     }
 
     fn public_key(&self) -> PublicKey {

nft_key/src/lib.rs

@@ -1,6 +1,6 @@
 use lib::{
     chain_key::{ext_chain_key_token_approval_receiver, ChainKeyToken, ChainKeyTokenApproval},
-    signer::{ext_signer, SignRequest, SignResult},
+    signer::{ext_signer, SignRequest, SignatureResponse},
     Rejectable,
 };
 use near_sdk::{
@@ -195,11 +195,11 @@ impl NftKeyContract {
     #[must_use]
     pub fn sign_callback(
         &self,
-        #[callback_result] result: Result<SignResult, PromiseError>,
+        #[callback_result] result: Result<SignatureResponse, PromiseError>,
     ) -> String {
-        let mpc_signature = result.unwrap();
+        let signature_response = result.unwrap();
         let ethers_signature: ethers_core::types::Signature =
-            mpc_signature.try_into().unwrap_or_reject();
+            signature_response.try_into().unwrap_or_reject();
         ethers_signature.to_string()
     }