From d6ab3503bc3977b64719027faebd7dc66c2dd42a Mon Sep 17 00:00:00 2001
From: ChronosX88 <chronosx88@gmail.com>
Date: Thu, 3 Dec 2020 01:18:47 +0400
Subject: [PATCH] Implement payload validation manager

---
 consensus/pre_prepare_pool.go                 | 26 +++----------
 consensus/validation/filecoin/filecoin.go     | 39 +++++++++++++++++++
 .../validation/payload_validation_manager.go  | 19 +++++++++
 3 files changed, 64 insertions(+), 20 deletions(-)
 create mode 100644 consensus/validation/filecoin/filecoin.go
 create mode 100644 consensus/validation/payload_validation_manager.go

diff --git a/consensus/pre_prepare_pool.go b/consensus/pre_prepare_pool.go
index d33075e..6d1d0ec 100644
--- a/consensus/pre_prepare_pool.go
+++ b/consensus/pre_prepare_pool.go
@@ -1,13 +1,11 @@
 package consensus
 
 import (
-	"bytes"
 	"fmt"
 
+	"github.com/Secured-Finance/dione/consensus/validation"
 	rtypes "github.com/Secured-Finance/dione/rpc/types"
 
-	ftypes "github.com/Secured-Finance/dione/rpc/filecoin/types"
-
 	oracleEmitter "github.com/Secured-Finance/dione/contracts/oracleemitter"
 
 	"github.com/Secured-Finance/dione/node"
@@ -167,23 +165,11 @@ func (ppp *PrePreparePool) IsValidPrePrepare(prePrepare *types2.Message) bool {
 	}
 	//////////////////////////////////////
 
-	// === verify filecoin message signature ===
-	if consensusMsg.Task.OriginChain == rtypes.RPCTypeFilecoin && consensusMsg.Task.RequestType == "getTransaction" {
-		var msg ftypes.SignedMessage
-		if err := msg.UnmarshalCBOR(bytes.NewReader(consensusMsg.Task.Payload)); err != nil {
-			if err := msg.Message.UnmarshalCBOR(bytes.NewReader(consensusMsg.Task.Payload)); err != nil {
-				return false
-			}
-		}
-
-		if msg.Type == ftypes.MessageTypeSecp256k1 {
-			if err = sigs.Verify(msg.Signature, msg.Message.From.Bytes(), msg.Message.Cid().Bytes()); err != nil {
-				logrus.Errorf("Couldn't verify transaction %v", err)
-			}
-			return true
-		} else {
-			// TODO: BLS Signature verification
-			return true
+	// === validate payload by specific-chain checks ===
+	if validationFunc := validation.GetValidationMethod(rtypes.RPCTypeFilecoin, consensusMsg.Task.RequestType); validationFunc != nil {
+		err := validationFunc(consensusMsg.Task.Payload)
+		if err != nil {
+			logrus.Errorf("payload validation has failed: %v", err)
 		}
 	}
 	/////////////////////////////////
diff --git a/consensus/validation/filecoin/filecoin.go b/consensus/validation/filecoin/filecoin.go
new file mode 100644
index 0000000..af9322d
--- /dev/null
+++ b/consensus/validation/filecoin/filecoin.go
@@ -0,0 +1,39 @@
+package filecoin
+
+import (
+	"bytes"
+
+	"github.com/Secured-Finance/dione/consensus/validation"
+	rtypes "github.com/Secured-Finance/dione/rpc/types"
+
+	ftypes "github.com/Secured-Finance/dione/rpc/filecoin/types"
+	"github.com/Secured-Finance/dione/sigs"
+	"github.com/sirupsen/logrus"
+	"golang.org/x/xerrors"
+)
+
+func ValidateGetTransaction(payload []byte) error {
+	var msg ftypes.SignedMessage
+	if err := msg.UnmarshalCBOR(bytes.NewReader(payload)); err != nil {
+		if err := msg.Message.UnmarshalCBOR(bytes.NewReader(payload)); err != nil {
+			return xerrors.Errorf("cannot unmarshal payload")
+		}
+	}
+
+	if msg.Type == ftypes.MessageTypeSecp256k1 {
+		if err := sigs.Verify(msg.Signature, msg.Message.From.Bytes(), msg.Message.Cid().Bytes()); err != nil {
+			logrus.Errorf("Couldn't verify transaction %v", err)
+			return xerrors.Errorf("Couldn't verify transaction: %v")
+		}
+		return nil
+	} else {
+		// TODO: BLS Signature verification
+		return nil
+	}
+}
+
+func init() {
+	validation.RegisterValidation(rtypes.RPCTypeFilecoin, map[string]func([]byte) error{
+		"getTransaction": ValidateGetTransaction,
+	})
+}
diff --git a/consensus/validation/payload_validation_manager.go b/consensus/validation/payload_validation_manager.go
new file mode 100644
index 0000000..0eed568
--- /dev/null
+++ b/consensus/validation/payload_validation_manager.go
@@ -0,0 +1,19 @@
+package validation
+
+var validations = map[uint8]map[string]func([]byte) error{} // rpcType -> {rpcMethodName -> actual func var}
+
+func RegisterValidation(typ uint8, methods map[string]func([]byte) error) {
+	validations[typ] = methods
+}
+
+func GetValidationMethod(typ uint8, methodName string) func([]byte) error {
+	rpcMethods, ok := validations[typ]
+	if !ok {
+		return nil
+	}
+	actualMethod, ok := rpcMethods[methodName]
+	if !ok {
+		return nil
+	}
+	return actualMethod
+}