Remove reliance on default Signer

This change allows the default privValidator to use a custom Signer
implementation with no reliance on the default Signer implementation.

cmd/hsm/main.go

@@ -35,8 +35,12 @@ func main() {
 	rootCmd.AddCommand(tc.TestnetFilesCmd)
 	rootCmd.AddCommand(tc.VersionCmd)
 
-	privValidator := types.LoadOrGenPrivValidator(config.PrivValidatorFile(), logger)
-	privValidator.SetSigner(types.NewDefaultSigner(privValidator.PrivKey))
+	// Override with HSM implementation, otherwise nil will trigger default
+	// software signer:
+	var signer types.Signer = nil
+
+	privValidator := types.LoadPrivValidatorWithSigner(config.PrivValidatorFile(),
+		signer)
 	rootCmd.AddCommand(tc.NewRunNodeCmd(privValidator))
 
 	cmd := cli.PrepareBaseCmd(rootCmd, "TM", os.ExpandEnv("$HOME/.tendermint"))

types/priv_validator.go

@@ -112,6 +112,10 @@ func GenPrivValidator() *PrivValidator {
 }
 
 func LoadPrivValidator(filePath string) *PrivValidator {
+	return LoadPrivValidatorWithSigner(filePath, nil)
+}
+
+func LoadPrivValidatorWithSigner(filePath string, signer Signer) *PrivValidator {
 	privValJSONBytes, err := ioutil.ReadFile(filePath)
 	if err != nil {
 		Exit(err.Error())
@@ -123,7 +127,11 @@ func LoadPrivValidator(filePath string) *PrivValidator {
 	}
 
 	privVal.filePath = filePath
-	privVal.Signer = NewDefaultSigner(privVal.PrivKey)
+	if signer == nil {
+		privVal.Signer = NewDefaultSigner(privVal.PrivKey)
+	} else {
+		privVal.Signer = signer
+	}
 	privVal.setPubKeyAndAddress()
 	return &privVal
 }