java.lang.Object
java.lang.Enum<SigType>
net.i2p.crypto.SigType
All Implemented Interfaces:
Serializable, Comparable<SigType>, java.lang.constant.Constable
public enum SigTypeextends Enum<SigType>
Defines the properties for various signature types that I2P supports or may someday support.

All Signatures, SigningPublicKeys, and SigningPrivateKeys have a type. Note that a SigType specifies both an algorithm and parameters, so that we may change primes or curves for a given algorithm.

  • Enum Constant Details

    • DSA_SHA1

      public static final SigType DSA_SHA1
      DSA_SHA1 is the default. Pubkey 128 bytes; privkey 20 bytes; hash 20 bytes; sig 40 bytes.

    • ECDSA_SHA256_P256

      public static final SigType ECDSA_SHA256_P256
      Pubkey 64 bytes; privkey 32 bytes; hash 32 bytes; sig 64 bytes.

    • ECDSA_SHA384_P384

      public static final SigType ECDSA_SHA384_P384
      Pubkey 96 bytes; privkey 48 bytes; hash 48 bytes; sig 96 bytes.

    • ECDSA_SHA512_P521

      public static final SigType ECDSA_SHA512_P521
      Pubkey 132 bytes; privkey 66 bytes; hash 64 bytes; sig 132 bytes.

    • RSA_SHA256_2048

      public static final SigType RSA_SHA256_2048
      Pubkey 256 bytes; privkey 512 bytes; hash 32 bytes; sig 256 bytes.

    • RSA_SHA384_3072

      public static final SigType RSA_SHA384_3072
      Pubkey 384 bytes; privkey 768 bytes; hash 48 bytes; sig 384 bytes.

    • RSA_SHA512_4096

      public static final SigType RSA_SHA512_4096
      Pubkey 512 bytes; privkey 1024 bytes; hash 64 bytes; sig 512 bytes.

    • EdDSA_SHA512_Ed25519

      public static final SigType EdDSA_SHA512_Ed25519
      Pubkey 32 bytes; privkey 32 bytes; hash 64 bytes; sig 64 bytes

      Due to bugs in previous versions, minimum version is 0.9.17.

    • EdDSA_SHA512_Ed25519ph

      public static final SigType EdDSA_SHA512_Ed25519ph
      Prehash version (double hashing, for offline use such as su3, not for use on the network) Pubkey 32 bytes; privkey 32 bytes; hash 64 bytes; sig 64 bytes.

    • RedDSA_SHA512_Ed25519

      public static final SigType RedDSA_SHA512_Ed25519
      Blinded version of EdDSA, use for encrypted LS2 Pubkey 32 bytes; privkey 32 bytes; hash 64 bytes; sig 64 bytes.

  • Field Details

    • code

      private final int code
      The two byte signature type code.

    • pubkeyLen

      private final int pubkeyLen
      Length of the public key, in bytes.

    • privkeyLen

      private final int privkeyLen
      Length of the private key, in bytes.

    • hashLen

      private final int hashLen
      Length of the hash signed, in bytes.

    • sigLen

      private final int sigLen
      Length of the signature, in bytes.

    • base

      private final SigAlgo base
      The underlying algorithm family.

    • digestName

      private final String digestName
      Name of the digest algorithm used.

    • algoName

      private final String algoName
      Name of the signature algorithm for display.

    • oid

      private final String oid
      The object identifier of the algorithm, if any.

    • since

      private final String since
      Version that introduced this type.

    • params

      private final AlgorithmParameterSpec params
      Parameters of the algorithm, if any.

    • isAvail

      private final boolean isAvail
      True if the implementation is available.

    • digestProto

      private volatile MessageDigest digestProto
      Pristine digest for digestName, created once and cloned per call. Never handed out and never fed data, so any clone of it is a fully independent digest in its initial state. Lazily created by getDigestPrototype() so that an unavailable algorithm still leaves the enum constant constructible.

    • BY_CODE

      private static final SigType[] BY_CODE
      The types indexed by their code.

  • Constructor Details

    • SigType

      private SigType(int cod, int pubLen, int privLen, int hLen, int sLen, SigAlgo baseAlgo, String mdName, String aName, AlgorithmParameterSpec pSpec, String oid, String supportedSince)
      Creates a signature type with its parameters.
      Parameters:
      cod - the two byte signature type code
      pubLen - length of the public key, in bytes
      privLen - length of the private key, in bytes
      hLen - length of the hash signed, in bytes
      sLen - length of the signature, in bytes
      baseAlgo - the underlying algorithm family
      mdName - name of the digest algorithm used
      aName - name of the signature algorithm for display
      pSpec - parameters of the algorithm, null if none
      oid - the object identifier of the algorithm, null if none
      supportedSince - version that introduced this type

  • Method Details

    • values

      public static SigType[] values()
      Returns an array containing the constants of this enum class, in the order they are declared.
      Returns:
      an array containing the constants of this enum class, in the order they are declared

    • valueOf

      public static SigType valueOf(String name)
      Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (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:
      IllegalArgumentException - if this enum class has no constant with the specified name
      NullPointerException - if the argument is null

    • getCode

      public int getCode()
      The unique identifier for this type.
      Returns:
      the code carried in the RouterIdentity

    • getPubkeyLen

      public int getPubkeyLen()
      The length of the public key, in bytes.
      Returns:
      the public key size

    • getPrivkeyLen

      public int getPrivkeyLen()
      The length of the private key, in bytes.
      Returns:
      the private key size

    • getHashLen

      public int getHashLen()
      The length of the hash, in bytes.
      Returns:
      the digest size

    • getSigLen

      public int getSigLen()
      The length of the signature, in bytes.
      Returns:
      the signature size

    • getBaseAlgorithm

      public SigAlgo getBaseAlgorithm()
      The standard base algorithm name used for the Java crypto factories.
      Returns:
      the key family, one of DSA, EC, RSA or EdDSA

    • getAlgorithmName

      public String getAlgorithmName()
      The standard name used for the Java crypto factories.
      Returns:
      the JCA signature algorithm name, e.g. SHA256withECDSA

    • getParams

      public AlgorithmParameterSpec getParams() throws InvalidParameterSpecException
      The elliptic curve ECParameterSpec for ECDSA; DSAParameterSpec for DSA.
      Returns:
      the domain parameters this signature type was created with, an ECParameterSpec for ECDSA or a DSAParameterSpec for DSA
      Throws:
      InvalidParameterSpecException - if the algorithm is not available on this JVM.

    • getDigestInstance

      public MessageDigest getDigestInstance()
      A private, unshared MessageDigest instance for this signature type, in its initial state.

      A MessageDigest is stateful and not thread safe, so the prototype is never returned directly; it is cloned on every call. Cloning skips the JCA provider lookup (algorithm string hashing plus provider list scanning) that MessageDigest.getInstance(String) performs, and the clone shares no state with the prototype or with any other clone.

      Returns:
      a new digest instance owned by the caller
      Throws:
      UnsupportedOperationException - if not supported

    • getDigestPrototype

      private MessageDigest getDigestPrototype()
      The pristine digest prototype for this type, created on first use.
      Returns:
      the prototype, which callers must not use or modify
      Throws:
      UnsupportedOperationException - if not supported

    • createDigestInstance

      private static MessageDigest createDigestInstance(String name)
      Provider lookup for a digest by name. Called at most once per SigType.
      Parameters:
      name - the JCA digest name
      Returns:
      a new digest instance
      Throws:
      UnsupportedOperationException - if not supported

    • getHashInstance

      public SimpleDataStructure getHashInstance()
      Create a Hash instance for this signature type.
      Returns:
      the hash instance
      Throws:
      UnsupportedOperationException - if not supported

    • getSupportedSince

      public String getSupportedSince()
      The router version in which this type was first supported.
      Returns:
      the supported since

    • getOID

      public String getOID()
      The object identifier assigned to the signature algorithm.
      Returns:
      the dotted decimal OID, null if none is assigned

    • isAvailable

      public boolean isAvailable()
      Checks if this signature type is available in the JVM.
      Returns:
      true if supported in this JVM

    • x_isAvailable

      private boolean x_isAvailable()
      Checks whether the implementation loads.
      Returns:
      true if the signatures can be verified

    • isAvailable

      public static boolean isAvailable(int code)
      Checks if the signature type with the given code is available.
      Parameters:
      code - the signature type code to look up
      Returns:
      true if supported in this JVM

    • isAvailable

      public static boolean isAvailable(String stype)
      Checks if the signature type with the given name or number is available.
      Parameters:
      stype - number or name
      Returns:
      true if supported in this JVM

    • getByCode

      public static SigType getByCode(int code)
      Signature type by code.
      Parameters:
      code - the signature type code to look up
      Returns:
      Null if not supported.

    • parseSigType

      public static SigType parseSigType(String stype)
      Convenience for user apps.
      Parameters:
      stype - number or name
      Returns:
      null if not found