add -confirm-key option

choice.go

@@ -31,14 +31,43 @@ chooseKey:
 			fmt.Print("\n")
 		default:
 			key = hash([]byte(in))
-
 			memory.Zero(&in)
 
+			if confirmKey {
+				fmt.Print(eviInput)
+
+				in, err := line(true)
+				if err != nil {
+					fmt.Printf(eviError, err)
+					os.Exit(1)
+				}
+
+				confirmedKey := hash([]byte(in))
+				memory.Zero(&in)
+
+				if !keysMatch(key, confirmedKey) {
+					fmt.Printf(eviError, "keys do not match")
+					os.Exit(1)
+				}
+			}
+
 			break chooseKey
 		}
 	}
 }
 
+func keysMatch(key, confirmedKey []byte) bool {
+	if len(key) != len(confirmedKey) {
+		return false
+	}
+	for i, b := range key {
+		if b != confirmedKey[i] {
+			return false
+		}
+	}
+	return true
+}
+
 func removeFile() {
 	fmt.Printf(eviInfo, "Remove file? [y/N]")
 	fmt.Print(eviInput)

main.go

@@ -8,27 +8,32 @@ import (
 )
 
 var (
-	noDecrypt bool
-	noEdit    bool
-	noEncrypt bool
+	confirmKey bool
+	noDecrypt  bool
+	noEdit     bool
+	noEncrypt  bool
 )
 
 func main() {
 	var keyFlag string
-	flag.StringVar(&keyFlag, "key", "", "")
-	flag.StringVar(&keyFlag, "k", "", "")
+	flag.BoolVar(&confirmKey, "confirm-key", confirmKey, "")
+	flag.BoolVar(&confirmKey, "c", confirmKey, "")
+
+	flag.StringVar(&keyFlag, "key", keyFlag, "")
+	flag.StringVar(&keyFlag, "k", keyFlag, "")
 
 	flag.BoolVar(&noDecrypt, "no-decrypt", noDecrypt, "")
 	flag.BoolVar(&noEdit, "no-edit", noEdit, "")
 	flag.BoolVar(&noEncrypt, "no-encrypt", noEncrypt, "")
 
 	flag.Usage = func() {
 		fmt.Println("Usage: evi [options...] <file>")
-		fmt.Println(" -h, -help        Show this help menu")
-		fmt.Println(" -k, -key         Preset the encryption key")
-		fmt.Println("     -no-decrypt  Stop the program from decrypting the file")
-		fmt.Println("     -no-edit     Stop the program from opening the editor")
-		fmt.Println("     -no-encrypt  Stop the program from re-encrypting the file")
+		fmt.Println(" -c, -confirm-key  Program asks for key twice")
+		fmt.Println(" -h, -help         Show this help menu")
+		fmt.Println(" -k, -key          Preset the encryption key")
+		fmt.Println("     -no-decrypt   Stop the program from decrypting the file")
+		fmt.Println("     -no-edit      Stop the program from opening the editor")
+		fmt.Println("     -no-encrypt   Stop the program from re-encrypting the file")
 	}
 
 	flag.Parse()