Package com.itextpdf.signatures

Interface IExternalSignature

All Known Implementing Classes:
PrivateKeySignature
public interface IExternalSignature
Interface that needs to be implemented to do the actual signing. For instance: you'll have to implement this interface if you want to sign a PDF using a smart card.

  • Method Details

    • getDigestAlgorithmName

      String getDigestAlgorithmName()
      Returns the digest algorithm.
      Returns:
      The digest algorithm (e.g. "SHA-1", "SHA-256,...").

    • getSignatureAlgorithmName

      String getSignatureAlgorithmName()
      Returns the signature algorithm used for signing, disregarding the digest function.
      Returns:
      The signature algorithm ("RSA", "DSA", "ECDSA", "Ed25519" or "Ed448").

    • getSignatureMechanismParameters

      ISignatureMechanismParams getSignatureMechanismParameters()
      Return the algorithm parameters that need to be encoded together with the signature mechanism identifier. If there are no parameters, return `null`. A non-null value is required for RSASSA-PSS; see RSASSAPSSMechanismParams.
      Returns:
      algorithm parameters

    • sign

      byte[] sign (byte[] message) throws GeneralSecurityException
      Signs the given message using the encryption algorithm in combination with the hash algorithm.
      Parameters:
      message - The message you want to be hashed and signed.
      Returns:
      A signed message digest.
      Throws:
      GeneralSecurityException - when requested cryptographic algorithm or security provider is not available