Package org.bouncycastle.crypto.signers

## Class PSSSigner

- java.lang.Object
- - org.bouncycastle.crypto.signers.PSSSigner

- All Implemented Interfaces:
    `Signer`

      public class PSSSigner
      extends java.lang.Object
      implements Signer

  RSA-PSS as described in PKCS# 1 v 2.1.

  Note: the usual value for the salt length is the number of bytes in the hash function.

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `static byte` | `TRAILER_IMPLICIT` |

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest digest, byte[] salt)` |
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest digest, int sLen)` | basic constructor
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest digest, int sLen, byte trailer)` |
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest contentDigest, Digest mgfDigest, byte[] salt)` |
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest contentDigest, Digest mgfDigest, byte[] salt, byte trailer)` |
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest contentDigest, Digest mgfDigest, int sLen)` |
    `PSSSigner​(AsymmetricBlockCipher cipher, Digest contentDigest, Digest mgfDigest, int sLen, byte trailer)` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `byte[]` | `generateSignature()` | generate a signature for the message we've been loaded with using the key we were initialised with.
    `void` | `init​(boolean forSigning, CipherParameters param)` | Initialise the signer for signing or verification.
    `void` | `reset()` | reset the internal state
    `void` | `update​(byte b)` | update the internal digest with the byte b
    `void` | `update​(byte[] in, int off, int len)` | update the internal digest with the byte array in
    `boolean` | `verifySignature​(byte[] signature)` | return true if the internal state represents the signature described in the passed in array.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Field Detail

    - #### TRAILER_IMPLICIT

          public static final byte TRAILER_IMPLICIT

      See Also:
        Constant Field Values

  - ### Constructor Detail

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest digest,
                           int sLen)

      basic constructor
      Parameters:
        `cipher` - the asymmetric cipher to use.
        `digest` - the digest to use.
        `sLen` - the length of the salt to use (in bytes).

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest contentDigest,
                           Digest mgfDigest,
                           int sLen)

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest digest,
                           int sLen,
                           byte trailer)

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest contentDigest,
                           Digest mgfDigest,
                           int sLen,
                           byte trailer)

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest digest,
                           byte[] salt)

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest contentDigest,
                           Digest mgfDigest,
                           byte[] salt)

    - #### PSSSigner

          public PSSSigner​(AsymmetricBlockCipher cipher,
                           Digest contentDigest,
                           Digest mgfDigest,
                           byte[] salt,
                           byte trailer)

  - ### Method Detail

    - #### init

          public void init​(boolean forSigning,
                           CipherParameters param)

      Description copied from interface: `Signer`
      Initialise the signer for signing or verification.
      Specified by:
        `init` in interface `Signer`
      Parameters:
        `forSigning` - true if for signing, false otherwise
        `param` - necessary parameters.

    - #### update

          public void update​(byte b)

      update the internal digest with the byte b
      Specified by:
        `update` in interface `Signer`

    - #### update

          public void update​(byte[] in,
                             int off,
                             int len)

      update the internal digest with the byte array in
      Specified by:
        `update` in interface `Signer`

    - #### reset

          public void reset()

      reset the internal state
      Specified by:
        `reset` in interface `Signer`

    - #### generateSignature

          public byte[] generateSignature()
                                   throws CryptoException,
                                          DataLengthException

      generate a signature for the message we've been loaded with using the key we were initialised with.
      Specified by:
        `generateSignature` in interface `Signer`
      Throws:
        `CryptoException`
        `DataLengthException`

    - #### verifySignature

          public boolean verifySignature​(byte[] signature)

      return true if the internal state represents the signature described in the passed in array.
      Specified by:
        `verifySignature` in interface `Signer`