Package com.ongres.scram.common

Enum ScramMechanisms

  • All Implemented Interfaces:
    ScramMechanism, java.io.Serializable, java.lang.Comparable<ScramMechanisms>
    public enum ScramMechanisms
extends java.lang.Enum<ScramMechanisms>
implements ScramMechanism
    SCRAM Mechanisms supported by this library. At least, SCRAM-SHA-1 and SCRAM-SHA-256 are provided, since both the hash and the HMAC implementations are provided by the Java JDK version 6 or greater. MessageDigest: "Every implementation of the Java platform is required to support the following standard MessageDigest algorithms: MD5, SHA-1, SHA-256". Mac: "Every implementation of the Java platform is required to support the following standard Mac algorithms: HmacMD5, HmacSHA1, HmacSHA256".
    See Also:
    SASL SCRAM Family Mechanisms

    • Field Detail

      • SCRAM_MECHANISM_NAME_PREFIX

        private static final java.lang.String SCRAM_MECHANISM_NAME_PREFIX
        See Also:
        Constant Field Values

      • CHANNEL_BINDING_SUFFIX

        private static final java.lang.String CHANNEL_BINDING_SUFFIX
        See Also:
        Constant Field Values

      • PBKDF2_PREFIX_ALGORITHM_NAME

        private static final java.lang.String PBKDF2_PREFIX_ALGORITHM_NAME
        See Also:
        Constant Field Values

      • BY_NAME_MAPPING

        private static final java.util.Map<java.lang.String,​ScramMechanisms> BY_NAME_MAPPING

      • mechanismName

        private final java.lang.String mechanismName

      • hashAlgorithmName

        private final java.lang.String hashAlgorithmName

      • keyLength

        private final int keyLength

      • hmacAlgorithmName

        private final java.lang.String hmacAlgorithmName

      • channelBinding

        private final boolean channelBinding

      • priority

        private final int priority

    • Constructor Detail

      • ScramMechanisms

        private ScramMechanisms​(java.lang.String name,
                        java.lang.String hashAlgorithmName,
                        int keyLength,
                        java.lang.String hmacAlgorithmName,
                        boolean channelBinding,
                        int priority)

    • Method Detail

      • values

        public static ScramMechanisms[] values()
        Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows: 
        for (ScramMechanisms c : ScramMechanisms.values())
    System.out.println(c);
        Returns:
        an array containing the constants of this enum type, in the order they are declared

      • valueOf

        public static ScramMechanisms valueOf​(java.lang.String name)
        Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
        Parameters:
        name - the name of the enum constant to be returned.
        Returns:
        the enum constant with the specified name
        Throws:
        java.lang.IllegalArgumentException - if this enum type has no constant with the specified name
        java.lang.NullPointerException - if the argument is null

      • getHashAlgorithmName

        protected java.lang.String getHashAlgorithmName()
        Method that returns the name of the hash algorithm. It is protected since should be of no interest for direct users. The instance is supposed to provide abstractions over the algorithm names, and are not meant to be directly exposed.
        Returns:
        The name of the hash algorithm

      • getHmacAlgorithmName

        protected java.lang.String getHmacAlgorithmName()
        Method that returns the name of the HMAC algorithm. It is protected since should be of no interest for direct users. The instance is supposed to provide abstractions over the algorithm names, and are not meant to be directly exposed.
        Returns:
        The name of the HMAC algorithm

      • supportsChannelBinding

        public boolean supportsChannelBinding()
        Description copied from interface: ScramMechanism
        Whether this mechanism supports channel binding
        Specified by:
        supportsChannelBinding in interface ScramMechanism
        Returns:
        True if it supports channel binding, false otherwise

      • getMessageDigestInstance

        public java.security.MessageDigest getMessageDigestInstance()
        Description copied from interface: ScramMechanism
        Gets a constructed MessageDigest instance, according to the algorithm of the SCRAM mechanism.
        Specified by:
        getMessageDigestInstance in interface ScramMechanism
        Returns:
        The MessageDigest instance

      • getMacInstance

        public javax.crypto.Mac getMacInstance()
        Description copied from interface: ScramMechanism
        Gets a constructed Mac instance, according to the algorithm of the SCRAM mechanism.
        Specified by:
        getMacInstance in interface ScramMechanism
        Returns:
        The Mac instance

      • secretKeySpec

        public javax.crypto.spec.SecretKeySpec secretKeySpec​(byte[] key)
        Description copied from interface: ScramMechanism
        Generates a key of the algorith used, based on the key given.
        Specified by:
        secretKeySpec in interface ScramMechanism
        Parameters:
        key - The bytes of the key to use
        Returns:
        The instance of SecretKeySpec

      • secretKeyFactory

        public javax.crypto.SecretKeyFactory secretKeyFactory()
        Description copied from interface: ScramMechanism
        Gets a SecretKeyFactory for the given algorithm.
        Specified by:
        secretKeyFactory in interface ScramMechanism
        Returns:
        The SecretKeyFactory

      • algorithmKeyLength

        public int algorithmKeyLength()
        Description copied from interface: ScramMechanism
        Returns the length of the key length of the algorithm.
        Specified by:
        algorithmKeyLength in interface ScramMechanism
        Returns:
        The length (in bits)

      • byName

        public static java.util.Optional<ScramMechanisms> byName​(java.lang.String name)
        Gets a SCRAM mechanism, given its standard IANA name.
        Parameters:
        name - The standard IANA full name of the mechanism.
        Returns:
        An Optional instance that contains the ScramMechanism if it was found, or empty otherwise.

      • selectMatchingMechanism

        public static java.util.Optional<ScramMechanism> selectMatchingMechanism​(boolean channelBinding,
                                                                         java.lang.String... peerMechanisms)
        This class classifies SCRAM mechanisms by two properties: whether they support channel binding; and a priority, which is higher for safer algorithms (like SHA-256 vs SHA-1). Given a list of SCRAM mechanisms supported by the peer, pick one that matches the channel binding requirements and has the highest priority.
        Parameters:
        channelBinding - The type of matching mechanism searched for
        peerMechanisms - The mechanisms supported by the other peer
        Returns:
        The selected mechanism, or null if no mechanism matched