pss: Distill whisper elements in pss to a custom fallback crypto (ethersphere#1731)

* pss: Distilled whisper message structure and encryption to default crypto implementation.

Added Topic to PssMsg
Simplified PssMsg Payload to []byte
Moved crypto to own package

Author: kortatu

pss/api.go

@@ -117,13 +117,13 @@ func (pssapi *API) BaseAddr() (PssAddress, error) {
 // Retrieves the node's public key in hex form
 func (pssapi *API) GetPublicKey() (keybytes hexutil.Bytes) {
 	key := pssapi.Pss.PublicKey()
-	keybytes = pssapi.Pss.Crypto.FromECDSAPub(key)
+	keybytes = pssapi.Pss.Crypto.SerializePublicKey(key)
 	return keybytes
 }
 
 // Set Public key to associate with a particular Pss peer
 func (pssapi *API) SetPeerPublicKey(pubkey hexutil.Bytes, topic Topic, addr PssAddress) error {
-	pk, err := pssapi.Pss.Crypto.UnmarshalPubkey(pubkey)
+	pk, err := pssapi.Pss.Crypto.UnmarshalPublicKey(pubkey)
 	if err != nil {
 		return fmt.Errorf("Cannot unmarshal pubkey: %x", pubkey)
 	}

pss/client/client_test.go

@@ -25,6 +25,7 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/common/hexutil"
+	ethCrypto "github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/ethereum/go-ethereum/node"
 	"github.com/ethereum/go-ethereum/p2p"
@@ -45,7 +46,6 @@ type protoCtrl struct {
 }
 
 var (
-	cryptoUtils pss.CryptoUtils
 	// custom logging
 	psslogmain   log.Logger
 	pssprotocols map[string]*protoCtrl
@@ -62,8 +62,6 @@ func init() {
 
 	psslogmain = log.New("psslog", "*")
 
-	cryptoUtils = pss.NewCryptoUtils()
-
 	pssprotocols = make(map[string]*protoCtrl)
 }
 
@@ -231,13 +229,7 @@ func newServices() adapters.Services {
 	}
 	return adapters.Services{
 		"pss": func(ctx *adapters.ServiceContext) (node.Service, error) {
-			ctxlocal, cancel := context.WithTimeout(context.Background(), time.Second)
-			defer cancel()
-			keys, err := cryptoUtils.NewKeyPair(ctxlocal)
-			if err != nil {
-				return nil, err
-			}
-			privkey, err := cryptoUtils.GetPrivateKey(keys)
+			privkey, err := ethCrypto.GenerateKey()
 			if err != nil {
 				return nil, err
 			}