add MsgSubmitRepaymentAdaptorSignature

Author: keithsue

api/side/lending/lending.pulsar.go

@@ -94,6 +94,7 @@ message Repayment {
     string txid = 2;
     string tx = 3;
     string repay_adaptor_point = 4;
-    string borrower_signature = 5;
-    google.protobuf.Timestamp create_at = 6 [(gogoproto.nullable) = false, (gogoproto.stdtime) = true];
+    string dca_adaptor_signature = 5;
+    string borrower_signature = 6;
+    google.protobuf.Timestamp create_at = 7 [(gogoproto.nullable) = false, (gogoproto.stdtime) = true];
 }

api/side/lending/tx.pulsar.go

@@ -18,6 +18,7 @@ service Msg {
     rpc Approve(MsgApprove) returns (MsgApproveResponse);
     rpc Redeem(MsgRedeem) returns (MsgRedeemResponse);
     rpc Repay(MsgRepay) returns (MsgRepayResponse);
+    rpc SubmitRepaymentAdaptorSignature(MsgSubmitRepaymentAdaptorSignature) returns (MsgSubmitRepaymentAdaptorSignatureResponse);
     rpc Close(MsgClose) returns (MsgCloseResponse);
 }
 
@@ -107,6 +108,18 @@ message MsgApproveResponse {
 
 }
 
+message MsgSubmitRepaymentAdaptorSignature {
+    option (cosmos.msg.v1.signer) = "relayer";
+    
+    string relayer = 1;
+    string loan_id = 2;
+    string adaptor_signature = 3;
+}
+
+message MsgSubmitRepaymentAdaptorSignatureResponse {
+
+}
+
 message MsgClose {
     option (cosmos.msg.v1.signer) = "relayer";
 

api/side/lending/tx_grpc.pb.go

@@ -4,13 +4,15 @@ import (
 	"bytes"
 	"context"
 	"encoding/base64"
+	"encoding/hex"
 	"fmt"
 
 	"cosmossdk.io/math"
 	"github.com/btcsuite/btcd/btcutil/psbt"
 
 	sdk "github.com/cosmos/cosmos-sdk/types"
 
+	"github.com/sideprotocol/side/crypto/adaptor"
 	dlc "github.com/sideprotocol/side/x/dlc/types"
 	"github.com/sideprotocol/side/x/lending/types"
 )
@@ -275,6 +277,51 @@ func (m msgServer) Repay(goCtx context.Context, msg *types.MsgRepay) (*types.Msg
 	return &types.MsgRepayResponse{}, nil
 }
 
+// SubmitRepaymentAdaptorSignature implements types.MsgServer.
+func (m msgServer) SubmitRepaymentAdaptorSignature(goCtx context.Context, msg *types.MsgSubmitRepaymentAdaptorSignature) (*types.MsgSubmitRepaymentAdaptorSignatureResponse, error) {
+	if err := msg.ValidateBasic(); err != nil {
+		return nil, err
+	}
+
+	ctx := sdk.UnwrapSDKContext(goCtx)
+
+	if !m.HasLoan(ctx, msg.LoanId) {
+		return nil, types.ErrLoanNotExists
+	}
+
+	if !m.HasRepayment(ctx, msg.LoanId) {
+		return nil, types.ErrInvalidRepayment
+	}
+
+	repayment := m.GetRepayment(ctx, msg.LoanId)
+	if len(repayment.DcaAdaptorSignature) != 0 {
+		return nil, types.ErrRepaymentAdaptorSigAlreadyExists
+	}
+
+	loan := m.GetLoan(ctx, msg.LoanId)
+
+	adaptorSigBytes, _ := hex.DecodeString(msg.AdaptorSignature)
+	adaptorPointBytes, _ := hex.DecodeString(repayment.RepayAdaptorPoint)
+	pubKeyBytes, _ := hex.DecodeString(loan.Agency)
+
+	// TODO: calculate sig hash
+	sigHash := []byte{}
+
+	if !adaptor.Verify(adaptorSigBytes, sigHash, pubKeyBytes, adaptorPointBytes) {
+		return nil, types.ErrInvalidAdaptorSignature
+	}
+
+	repayment.DcaAdaptorSignature = msg.AdaptorSignature
+	m.SetRepayment(ctx, repayment)
+
+	m.EmitEvent(ctx, msg.Relayer,
+		sdk.NewAttribute("loan_id", msg.LoanId),
+		sdk.NewAttribute("adaptor_signature", msg.AdaptorSignature),
+	)
+
+	return &types.MsgSubmitRepaymentAdaptorSignatureResponse{}, nil
+}
+
 // Close implements types.MsgServer.
 func (m msgServer) Close(goCtx context.Context, msg *types.MsgClose) (*types.MsgCloseResponse, error) {
 	ctx := sdk.UnwrapSDKContext(goCtx)

proto/side/lending/lending.proto

@@ -38,8 +38,11 @@ var (
 	ErrEmptyLoanSecret    = errorsmod.Register(ModuleName, 5002, "invalid loan secret")
 	ErrMismatchLoanSecret = errorsmod.Register(ModuleName, 5003, "mismatch loan secret")
 
-	ErrEmptyAdaptorPoint      = errorsmod.Register(ModuleName, 6001, "invalid adaptor point")
-	ErrInvalidRepayment       = errorsmod.Register(ModuleName, 6002, "invalid repayment")
-	ErrInvalidRepaymentTx     = errorsmod.Register(ModuleName, 6003, "invalid repayment tx")
-	ErrInvalidRepaymentSecret = errorsmod.Register(ModuleName, 6003, "invalid repayment secret")
+	ErrEmptyAdaptorPoint                = errorsmod.Register(ModuleName, 6001, "invalid adaptor point")
+	ErrInvalidRepayment                 = errorsmod.Register(ModuleName, 6002, "invalid repayment")
+	ErrInvalidRepaymentTx               = errorsmod.Register(ModuleName, 6003, "invalid repayment tx")
+	ErrInvalidRepaymentSecret           = errorsmod.Register(ModuleName, 6004, "invalid repayment secret")
+	ErrRepaymentAdaptorSigAlreadyExists = errorsmod.Register(ModuleName, 6005, "repayment adaptor signature already exists")
+	ErrInvalidAdaptorSignature          = errorsmod.Register(ModuleName, 6006, "invalid adaptor signature")
+	ErrEmptyLoanId                      = errorsmod.Register(ModuleName, 6007, "empty loan id")
 )