PdfDigitalId Class

Namespace:
GemBox.Pdf.Security
Assembly:
GemBox.Pdf.dll

A digital ID used to sign and encrypt documents.

The certificate that comes with your digital ID is sent to others so that they can verify your signature.

The most secure digital IDs are issued by trusted Certificate authorities and are based on secure devices like smart card or token. Some are based on files.

public class PdfDigitalId
Public Class PdfDigitalId
Inheritance:
System.Object
PdfDigitalId
Derived
PdfDelayOrReSignDigitalId
PdfPkcs11DigitalId
Remarks

GemBox.Pdf doesn't use System.Security.Cryptography.X509Certificates.X509Certificate2 class to represent a digital ID because System.Security.Cryptography.X509Certificates.X509Certificate2 creates a file that holds the private key and another file that holds the certificate with the public key (in various locations on a hard drive) and on some operating systems and platforms those files are not deleted unless System.Security.Cryptography.X509Certificates.X509Certificate2.Reset method is called. This creation of files prevents usages of digital IDs in Medium Trust.

Another reason why GemBox.Pdf abstracts a digital ID with a PdfDigitalId class instead of using System.Security.Cryptography.X509Certificates.X509Certificate2 directly is to enable different implementations of a digital ID. For example, either System.Security.Cryptography.X509Certificates.X509Certificate2 implementation from .NET or Org.BouncyCastle.X509.X509Certificate with Org.BouncyCastle.Crypto.AsymmetricKeyParameter (private key) implementation from Bouncy Castle could be used.

Lastly, GemBox.Pdf abstracts a digital ID with a PdfDigitalId class to enable usage of signers for which private key parameters cannot be exported into .NET or Bouncy Castle implementation. These are, for example, Hardware Security Module (HSM), USB token, smart card or a web service and their functionality is called when overriding GemBox.Pdf.Security.PdfDigitalId.SignHash(System.Byte[], GemBox.Pdf.Security.PdfHashAlgorithm, GemBox.Pdf.Security.PdfRSASignaturePadding) method.

Constructors

PdfDigitalId(Object)

Initializes a new instance of the PdfDigitalId class from the specified source.

The digital ID source is either an instance of a System.Security.Cryptography.X509Certificates.X509Certificate2 with a private key or an instance of a System.Security.Cryptography.CspParameters.

public PdfDigitalId(object source)
Public Sub New(source As Object)
Parameters
source
System.Object

The digital ID source that is either an instance of a System.Security.Cryptography.X509Certificates.X509Certificate2 with a private key or an instance of a System.Security.Cryptography.CspParameters.

Exceptions
System.ArgumentException

The source parameter is not an instance of a System.Security.Cryptography.X509Certificates.X509Certificate2 or a System.Security.Cryptography.CspParameters.

System.InvalidOperationException

Digital ID doesn't have a private key.

PdfDigitalId(String, String)

Initializes a new instance of the PdfDigitalId class from a file with the specified file name and the password protecting the private key.

The most common format for such files is a PKCS#12 file, which uses .pfx or .p12 file extension and is a password protected storage container for digital IDs containing the public key (Certificate) and the associated private key.

public PdfDigitalId(string fileName, string password)
Public Sub New(fileName As String, password As String)
Parameters
fileName
System.String

The name of a digital ID file that contains the public key (Certificate) and the associated private key.

password
System.String

The password protecting the private key.

Exceptions
System.ArgumentNullException

fileName is null.

System.InvalidOperationException

Digital ID doesn't have a private key.

Properties

Certificate

Gets or sets the certificate.

public PdfCertificate Certificate { get; set; }
Public Property Certificate As PdfCertificate
Property Value
PdfCertificate

The certificate.

Exceptions
System.InvalidOperationException

The Certificate is already set.

System.ArgumentNullException

Value is null.

Methods

ToString()

Returns a System.String that represents this PdfDigitalId instance.

public override string ToString()
Public Overrides Function ToString As String
Returns
System.String

A System.String that represents this PdfDigitalId instance.

Overrides
System.Object.ToString()
Remarks

This method should be used primarily for debugging purposes and should be considered volatile (format of its return value might change in future versions).

Examples