Package de.uplanet.security

Class Salt

  • @Scriptable
public final class Salt
extends Object
    Used to create cryptographically secure random strings that can be used as salt values.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int DEFAULT_SALT_LENGTH
      The default length of a salt string in bytes (16).

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static String get()
      Create a cryptographically secure hex-encoded salt value of the default length in bytes.
      static String get​(byte[] p_key, int p_iLen)
      Create a hex-encoded salt value of the given length in bytes.
      static String get​(int p_iLen)
      Create a cryptographically secure hex-encoded salt value of the given length in bytes.
      static byte[] getBinary()
      Create cryptographically secure salt value of the default length in bytes.
      static byte[] getBinary​(byte[] p_key, int p_iLen)
      Create a salt value of the given length in bytes.
      static byte[] getBinary​(int p_iLen)
      Create a cryptographically secure hex-encoded salt value of the given length in bytes.
      static byte[] toBinary​(String p_strHex)
      Convert the given hex string to bytes.
      static String toHex​(byte[] p_buf)
      Convert the given bytes to a hex-encoded string.

    • Field Detail

      • DEFAULT_SALT_LENGTH

        public static final int DEFAULT_SALT_LENGTH
        The default length of a salt string in bytes (16).
        See Also:
        Constant Field Values

    • Method Detail

      • get

        public static String get()
        Create a cryptographically secure hex-encoded salt value of the default length in bytes.

        Note that the length of the returned hex-encoded string is twice of the length in bytes.

        Returns:
        The hex-encoded salt value.
        See Also:
        getBinary()

      • getBinary

        public static byte[] getBinary()
        Create cryptographically secure salt value of the default length in bytes.
        Returns:
        The salt value.
        See Also:
        getBinary(int)

      • get

        public static String get​(int p_iLen)
        Create a cryptographically secure hex-encoded salt value of the given length in bytes.

        Note that the length of the returned hex-encoded string is twice of the length in bytes.

        Parameters:
        p_iLen - The length of the salt value in bytes.
        Returns:
        The hex-encoded salt value.

      • getBinary

        public static byte[] getBinary​(int p_iLen)
        Create a cryptographically secure hex-encoded salt value of the given length in bytes.
        Parameters:
        p_iLen - The length of the salt value in bytes.
        Returns:
        The salt value.

      • get

        public static String get​(byte[] p_key,
                         int p_iLen)
        Create a hex-encoded salt value of the given length in bytes.

        The created salt is only cryptographically secure if the provided key material is cryptographically secure, i.e. contains cryptographically secure random bits.

        The derived salt value contains at most 256 bits of entropy.

        The given key material cannot be recovered from the generated salt.

        Note that the length of the returned hex-encoded string is twice of the length in bytes.

        Parameters:
        p_key - The key material that determines the value of the salt.
        p_iLen - The length of the salt value in bytes.
        Returns:
        The hex-encoded salt value.

      • getBinary

        public static byte[] getBinary​(byte[] p_key,
                               int p_iLen)
        Create a salt value of the given length in bytes.

        The created salt is only cryptographically secure if the provided key material is cryptographically secure, i.e. contains cryptographically secure random bits.

        The derived salt value contains at most 256 bits of entropy.

        The given key material cannot be recovered from the generated salt.

        Parameters:
        p_key - The key material that determines the value of the salt.
        p_iLen - The length of the salt value in bytes.
        Returns:
        The salt value.

      • toHex

        public static String toHex​(byte[] p_buf)
        Convert the given bytes to a hex-encoded string.
        Parameters:
        p_buf - The bytes to convert
        Returns:
        The hex-encoded bytes.

      • toBinary

        public static byte[] toBinary​(String p_strHex)
        Convert the given hex string to bytes.
        Parameters:
        p_strHex - A string of hex-encoded bytes.
        Returns:
        The decoded bytes.
        Throws:
        IllegalArgumentException - If the input length is odd or if the input contains non-hexadecimal digits.