update linter config, satisfy linter (#28)

app/crypto.go

@@ -1,3 +1,5 @@
+package app
+
 /*
 Copyright © 2024 Thomas von Dein
 
@@ -14,7 +16,6 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
-package app
 
 import (
 	"crypto/rand"
@@ -35,7 +36,7 @@ const (
 	ArgonParallel uint8  = 2
 	ArgonSaltLen  int    = 16
 	ArgonKeyLen   uint32 = 32
-	B64SaltLen    int    = 16 //22
+	B64SaltLen    int    = 16 // 22
 )
 
 type Key struct {
@@ -47,7 +48,8 @@ type Key struct {
 // password
 func AskForPassword() ([]byte, error) {
 	fmt.Fprint(os.Stderr, "Password: ")
-	pass, err := term.ReadPassword(int(syscall.Stdin))
+
+	pass, err := term.ReadPassword(syscall.Stdin)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read password: %w", err)
 	}
@@ -57,6 +59,8 @@ func AskForPassword() ([]byte, error) {
 	return pass, nil
 }
 
+// DeriveKey derives a key from password.
+//
 // We're  using the  Argon2id  key derivation  algorithm  to derive  a
 // secure  key from  the given  password. This  is important,  because
 // users might  use unsecure  passwords. The resulting  encrypted data
@@ -78,7 +82,7 @@ func DeriveKey(password []byte, salt []byte) (*Key, error) {
 	}
 
 	hash := argon2.IDKey(
-		[]byte(password), salt,
+		password, salt,
 		ArgonIter,
 		ArgonMem,
 		ArgonParallel,
@@ -95,6 +99,7 @@ func DeriveKey(password []byte, salt []byte) (*Key, error) {
 // Retrieve a random chunk of given size
 func GetRandom(size int, capacity int) ([]byte, error) {
 	buf := make([]byte, size, capacity)
+
 	_, err := rand.Read(buf)
 	if err != nil {
 		return nil, fmt.Errorf("failed to retrieve random bytes: %w", err)
@@ -103,7 +108,7 @@ func GetRandom(size int, capacity int) ([]byte, error) {
 	return buf, nil
 }
 
-// Encrypt clear  text given in  attr using ChaCha20  and auhtenticate
+// Encrypt clear  text given in  attr using ChaCha20  and authenticate
 // using the mac Poly1305. The cipher text will be put into attr, thus
 // modifying it.
 //
@@ -143,7 +148,7 @@ func Encrypt(pass []byte, attr *DbAttr) error {
 // Do the reverse
 func Decrypt(pass []byte, cipherb []byte) ([]byte, error) {
 	if len(cipherb) < B64SaltLen {
-		return nil, fmt.Errorf("encrypted cipher block too small")
+		return nil, errors.New("encrypted cipher block too small")
 	}
 
 	key, err := DeriveKey(pass, cipherb[0:B64SaltLen])