From d06321632438f233b12f85e68ac919402f8769fc Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Thu, 28 Nov 2019 23:52:35 +0100
Subject: [PATCH] Lint: Fix several linter advices

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 main.go    | 25 +++++++++++++------------
 ssh_key.go | 49 +++++++++++++++++++++++++------------------------
 2 files changed, 38 insertions(+), 36 deletions(-)

diff --git a/main.go b/main.go
index ea9175e..42a9e0b 100644
--- a/main.go
+++ b/main.go
@@ -121,8 +121,10 @@ func main() {
 	}
 
 	config := &ssh.ClientConfig{
-		User:            cfg.RemoteUser,
-		Auth:            []ssh.AuthMethod{privateKey},
+		User: cfg.RemoteUser,
+		Auth: []ssh.AuthMethod{privateKey},
+
+		//#nosec G106 // For now no validation is supported
 		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
 	}
 
@@ -212,15 +214,14 @@ func main() {
 		sigC <- syscall.SIGINT
 	}()
 
-	for {
-		select {
-		case <-sigC:
-			log.Info("Signal triggered, shutting down")
-			if err := session.Signal(ssh.SIGHUP); err != nil {
-				log.WithError(err).Error("Unable to send TERM signal to remote process")
-			}
-			running = false
-			return
-		}
+	// Wait for signal to occur
+	<-sigC
+
+	// Do a proper teardown
+	log.Info("Signal triggered, shutting down")
+	running = false
+
+	if err := session.Signal(ssh.SIGHUP); err != nil {
+		log.WithError(err).Error("Unable to send TERM signal to remote process")
 	}
 }
diff --git a/ssh_key.go b/ssh_key.go
index b281ae2..797bbac 100644
--- a/ssh_key.go
+++ b/ssh_key.go
@@ -3,19 +3,18 @@ package main
 import (
 	"crypto/x509"
 	"encoding/pem"
-	"errors"
-	"fmt"
 
+	"github.com/pkg/errors"
 	"golang.org/x/crypto/ssh"
 )
 
 func signerFromPem(pemBytes []byte, password []byte) (ssh.Signer, error) {
+	var err error
 
 	// read pem block
-	err := errors.New("Pem decode failed, no key found")
 	pemBlock, _ := pem.Decode(pemBytes)
 	if pemBlock == nil {
-		return nil, err
+		return nil, errors.New("Pem decode failed, no key found")
 	}
 
 	// handle encrypted key
@@ -23,7 +22,7 @@ func signerFromPem(pemBytes []byte, password []byte) (ssh.Signer, error) {
 		// decrypt PEM
 		pemBlock.Bytes, err = x509.DecryptPEMBlock(pemBlock, password)
 		if err != nil {
-			return nil, fmt.Errorf("Decrypting PEM block failed %v", err)
+			return nil, errors.Wrap(err, "Decrypting PEM block failed")
 		}
 
 		// get RSA, EC or DSA key
@@ -35,45 +34,47 @@ func signerFromPem(pemBytes []byte, password []byte) (ssh.Signer, error) {
 		// generate signer instance from key
 		signer, err := ssh.NewSignerFromKey(key)
 		if err != nil {
-			return nil, fmt.Errorf("Creating signer from encrypted key failed %v", err)
-		}
-
-		return signer, nil
-	} else {
-		// generate signer instance from plain key
-		signer, err := ssh.ParsePrivateKey(pemBytes)
-		if err != nil {
-			return nil, fmt.Errorf("Parsing plain private key failed %v", err)
+			return nil, errors.Wrap(err, "Creating signer from encrypted key failed")
 		}
 
 		return signer, nil
 	}
+
+	// generate signer instance from plain key
+	signer, err := ssh.ParsePrivateKey(pemBytes)
+	if err != nil {
+		return nil, errors.Wrap(err, "Parsing plain private key failed")
+	}
+
+	return signer, nil
 }
 
 func parsePemBlock(block *pem.Block) (interface{}, error) {
 	switch block.Type {
+
 	case "RSA PRIVATE KEY":
 		key, err := x509.ParsePKCS1PrivateKey(block.Bytes)
 		if err != nil {
-			return nil, fmt.Errorf("Parsing PKCS private key failed %v", err)
-		} else {
-			return key, nil
+			return nil, errors.Wrap(err, "Parsing PKCS private key failed")
 		}
+		return key, nil
+
 	case "EC PRIVATE KEY":
 		key, err := x509.ParseECPrivateKey(block.Bytes)
 		if err != nil {
-			return nil, fmt.Errorf("Parsing EC private key failed %v", err)
-		} else {
-			return key, nil
+			return nil, errors.Wrap(err, "Parsing EC private key failed")
 		}
+		return key, nil
+
 	case "DSA PRIVATE KEY":
 		key, err := ssh.ParseDSAPrivateKey(block.Bytes)
 		if err != nil {
-			return nil, fmt.Errorf("Parsing DSA private key failed %v", err)
-		} else {
-			return key, nil
+			return nil, errors.Wrap(err, "Parsing DSA private key failed")
 		}
+		return key, nil
+
 	default:
-		return nil, fmt.Errorf("Parsing private key failed, unsupported key type %q", block.Type)
+		return nil, errors.Errorf("Parsing private key failed, unsupported key type %q", block.Type)
+
 	}
 }