Use canonical json

go.mod

@@ -26,6 +26,7 @@ require (
 	github.com/deckarep/golang-set v1.8.0 // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0 // indirect
 	github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f // indirect
+	github.com/gibson042/canonicaljson-go v1.0.3 // indirect
 	github.com/go-stack/stack v1.8.1 // indirect
 	github.com/google/uuid v1.3.0 // indirect
 	github.com/gorilla/websocket v1.5.0 // indirect

go.sum

@@ -54,6 +54,8 @@ github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/r
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/fsnotify/fsnotify v1.4.9/go.mod h1:znqG4EE+3YCdAaPaxE2ZRY/06pZUdp0tY4IgpuI1SZQ=
+github.com/gibson042/canonicaljson-go v1.0.3 h1:EAyF8L74AWabkyUmrvEFHEt/AGFQeD6RfwbAuf0j1bI=
+github.com/gibson042/canonicaljson-go v1.0.3/go.mod h1:DsLpJTThXyGNO+KZlI85C1/KDcImpP67k/RKVjcaEqo=
 github.com/go-chi/httpvcr v0.2.0 h1:jOsPvc4ZOoyNv9KCv/O4YoSjMFrHFq/Orc90A0DotUU=
 github.com/go-stack/stack v1.8.1 h1:ntEHSVwIt7PNXNpgPmVfMrNhLtgjlmnZha2kOpuRiDw=
 github.com/go-stack/stack v1.8.1/go.mod h1:dcoOX6HbPZSZptuspn9bctJ+N/CnF5gGygcUP3XYfe4=

intents/intent.go

@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/gibson042/canonicaljson-go"
+
 	"github.com/0xsequence/ethkit/go-ethereum/common"
 	"github.com/0xsequence/ethkit/go-ethereum/crypto"
 )
@@ -54,7 +56,7 @@ func (intent *Intent) Hash() ([]byte, error) {
 	packet := intent.Packet
 
 	// Convert packet to bytes
-	packetBytes, err := json.Marshal(packet)
+	packetBytes, err := canonicaljson.Marshal(packet)
 	if err != nil {
 		return nil, err
 	}