PDFEncrypt Component

Properties   Methods   Events   Config Settings   Errors  

The PDFEncrypt component encrypts PDF documents.

Syntax

nsoftware.SecurePDF.PDFEncrypt

Remarks

As with signing, PDF encryption is part of the PDF format itself. It is used to prevent unauthorized access to documents and is performed using either an encryption password (known as password-based or symmetric encryption) or the intended document recipient's public X.509 certificate (known as certificate-based or asymmetric encryption). The PDFEncrypt component supports both encryption types.

The benefit of this encryption scheme as defined in the standard is that encrypted PDF documents are still valid PDF documents and can be handled by almost any PDF reader. Of course, this software will need to be able to decrypt such documents, but it can always reach the metadata (information about the document) and document structure.

Password-Based Encryption

The following code shows how to encrypt a PDF document with a user password: pdfencrypt.InputFile = "input.pdf"; pdfencrypt.OutputFile = "password_encrypted.pdf"; pdfencrypt.Password = "password"; pdfencrypt.Encrypt(); Owner passwords are also supported. Compared to user passwords, these passwords are used to protect the permissions (set via the Permissions property) that will be embedded into the document. For example, you may want to prevent the recipient from printing or editing the document. You can encrypt the document with an owner password by specifying the OwnerPassword configuration setting before calling the Encrypt method.

Certificate-Based Encryption

The following code shows how to encrypt a PDF document with a certificate: pdfencrypt.InputFile = "input.pdf"; pdfencrypt.OutputFile = "cert_encrypted.pdf"; pdfencrypt.EncryptionCert = new Certificate(CertStoreTypes.cstPublicKeyFile, "C:/MyCerts/cert.cer", "", "*"); pdfencrypt.Encrypt(); When encrypting using either a password or certificate, set the EncryptionAlgorithm property to the desired encryption algorithm. As additional encryption options, you can also decide whether the document metadata will be encrypted and embed permissions into the document via the EncryptMetadata and Permissions properties respectively.

Property List

The following is the full list of the properties of the component with short descriptions. Click on the links for further details.

Method List

The following is the full list of the methods of the component with short descriptions. Click on the links for further details.

Event List

The following is the full list of the events fired by the component with short descriptions. Click on the links for further details.

Config Settings

The following is a list of config settings for the component with short descriptions. Click on the links for further details.

EncryptionAlgorithm Property (PDFEncrypt Component)

The encryption algorithm to encrypt the PDF document with.

Syntax

• C#
• VB.NET

public string EncryptionAlgorithm { get; set; }

Public Property EncryptionAlgorithm As String

Default Value

"AES256"

Remarks

This property is used to specify the encryption algorithm to encrypt the document with.

Possible values are:

• RC4
• AES128
• AES256

EncryptionCert Property (PDFEncrypt Component)

The encryption certificate.

Syntax

• C#
• VB.NET

public Certificate EncryptionCert { get; set; }

Public Property EncryptionCert As Certificate

Remarks

This property is used to provide the certificate used for encryption. Note that this certificate need not have a private key associated with it, but the intended recipient of the encrypted document does.

Note: Encryption for multiple recipients is currently unsupported.

This property is not available at design time.

EncryptMetadata Property (PDFEncrypt Component)

Whether to encrypt the document metadata.

Syntax

• C#
• VB.NET

public bool EncryptMetadata { get; set; }

Public Property EncryptMetadata As Boolean

Default Value

True

Remarks

This property indicates whether the document metadata will be encrypted when the Encrypt method is called. Metadata contains additional information about the document, such as its name and author.

InputData Property (PDFEncrypt Component)

A byte array containing the PDF document to process.

Syntax

• C#
• VB.NET

public byte[] InputData { get; set; }

Public Property InputData As Byte()

Remarks

This property is used to assign a byte array containing the PDF document to be processed.

This property is not available at design time.

InputFile Property (PDFEncrypt Component)

The PDF file to process.

Syntax

• C#
• VB.NET

public string InputFile { get; set; }

Public Property InputFile As String

Default Value

""

Remarks

This property is used to provide a path to the PDF document to be processed.

OutputData Property (PDFEncrypt Component)

A byte array containing the PDF document after processing.

Syntax

• C#
• VB.NET

public byte[] OutputData { get; }

Public ReadOnly Property OutputData As Byte()

Remarks

This property is used to read the byte array containing the produced output after the operation has completed. It will only be set if an output file and output stream have not been assigned via OutputFile and SetOutputStream respectively.

This property is read-only and not available at design time.

OutputFile Property (PDFEncrypt Component)

The path to a local file where the output will be written.

Syntax

• C#
• VB.NET

public string OutputFile { get; set; }

Public Property OutputFile As String

Default Value

""

Remarks

This property is used to provide a path where the resulting PDF document will be saved after the operation has completed.

Overwrite Property (PDFEncrypt Component)

Whether or not the component should overwrite files.

Syntax

• C#
• VB.NET

public bool Overwrite { get; set; }

Public Property Overwrite As Boolean

Default Value

False

Remarks

This property indicates whether or not the component will overwrite OutputFile, OutputData, or the stream set in SetOutputStream. If set to false, an error will be thrown whenever OutputFile, OutputData, or the stream set in SetOutputStream exists before an operation.

Password Property (PDFEncrypt Component)

The password to encrypt the document with.

Syntax

• C#
• VB.NET

public string Password { get; set; }

Public Property Password As String

Default Value

""

Remarks

This property is used to provide the user password for encryption. Though it may be different from OwnerPassword, most implementations use the same value for both.

Permissions Property (PDFEncrypt Component)

The document permissions associated with the encryption.

Syntax

• C#
• VB.NET

public int Permissions { get; set; }

Public Property Permissions As Integer

Default Value

0

Remarks

This property is used to specify the permissions protected by this encryption. The PDF specification expects applications to comply with these permissions when handling encrypted documents, but note that it is a policy-like requirement rather than an enforcement.

Its value should be provided as a bitmask of the following flags:

This property is not available at design time.

Close Method (PDFEncrypt Component)

Closes an opened PDF document.

Syntax

• C#
• VB.NET

public void Close();

Async Version
public async Task Close();
public async Task Close(CancellationToken cancellationToken);

Public Sub Close()

Async Version
Public Sub Close() As Task
Public Sub Close(cancellationToken As CancellationToken) As Task

Remarks

This method is used to close the previously opened document specified in InputFile, InputData, or SetInputStream. It should always be preceded by a call to the Open method.

Example: component.InputFile = "input.pdf"; component.Open(); // Some operation component.Close();

If any changes are made to the document, they will be saved automatically to OutputFile, OutputData, or the stream set in SetOutputStream when this method is called. To configure this saving behavior, set the SaveChanges configuration setting.

Config Method (PDFEncrypt Component)

Sets or retrieves a configuration setting.

Syntax

• C#
• VB.NET

public string Config(string configurationString);

Async Version
public async Task<string> Config(string configurationString);
public async Task<string> Config(string configurationString, CancellationToken cancellationToken);

Public Function Config(ByVal ConfigurationString As String) As String

Async Version
Public Function Config(ByVal ConfigurationString As String) As Task(Of String)
Public Function Config(ByVal ConfigurationString As String, cancellationToken As CancellationToken) As Task(Of String)

Remarks

Config is a generic method available in every component. It is used to set and retrieve configuration settings for the component.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the component, access to these internal properties is provided through the Config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

Encrypt Method (PDFEncrypt Component)

Encrypts a PDF document.

Syntax

• C#
• VB.NET

public void Encrypt();

Async Version
public async Task Encrypt();
public async Task Encrypt(CancellationToken cancellationToken);

Public Sub Encrypt()

Async Version
Public Sub Encrypt() As Task
Public Sub Encrypt(cancellationToken As CancellationToken) As Task

Remarks

This method is used to encrypt the PDF document specified in InputFile, InputData, or SetInputStream. The document will be encrypted using EncryptionAlgorithm and either Password (for password-based encryption) or EncryptionCert (for certificate-based encryption), then saved in OutputFile, OutputData, or the stream set in SetOutputStream.

Example: pdfencrypt.InputFile = "input.pdf"; pdfencrypt.OutputFile = "encrypted.pdf"; pdfencrypt.Password = "password"; pdfencrypt.EncryptionAlgorithm = "AES256"; pdfencrypt.Encrypt(); Note: If the document is not already opened, this method will open it, perform the operation, then close it.

Encrypted Method (PDFEncrypt Component)

Checks whether a PDF document is encrypted.

Syntax

• C#
• VB.NET

public bool Encrypted();

Async Version
public async Task<bool> Encrypted();
public async Task<bool> Encrypted(CancellationToken cancellationToken);

Public Function Encrypted() As Boolean

Async Version
Public Function Encrypted() As Task(Of Boolean)
Public Function Encrypted(cancellationToken As CancellationToken) As Task(Of Boolean)

Remarks

This method is used to determine whether or not the document specified in InputFile, InputData, or SetInputStream is encrypted. It will return false if the document is pseudo-encrypted with an empty password.

Example: pdfencrypt.InputFile = "input.pdf"; if (!pdfencrypt.Encrypted()) { pdfencrypt.OutputFile = "encrypted.pdf"; // Set Password or EncryptionCert pdfencrypt.Encrypt(); } Note: If the document is not already opened, this method will open it, perform the operation, then close it.

Open Method (PDFEncrypt Component)

Opens a PDF document for processing.

Syntax

• C#
• VB.NET

public void Open();

Async Version
public async Task Open();
public async Task Open(CancellationToken cancellationToken);

Public Sub Open()

Async Version
Public Sub Open() As Task
Public Sub Open(cancellationToken As CancellationToken) As Task

Remarks

This method is used to open the document specified in InputFile, InputData, or SetInputStream before performing some operation on it, such as signing, updating, verifying signatures, or removing signatures. When finished, call Close to complete or discard the operation.

It is recommended to use this method (alongside Close) when performing multiple operations on the document at once.

Automatic Decryption Functionality

Once the correct decryption material is supplied, the component will then attempt to decrypt the document automatically within this method. When this occurs, the decrypted content is kept in memory so that the document's encrypted status is preserved when it is saved later. Use the Decrypt method to save a decrypted copy of the document instead.

Reset Method (PDFEncrypt Component)

Resets the component.

Syntax

• C#
• VB.NET

public void Reset();

Async Version
public async Task Reset();
public async Task Reset(CancellationToken cancellationToken);

Public Sub Reset()

Async Version
Public Sub Reset() As Task
Public Sub Reset(cancellationToken As CancellationToken) As Task

Remarks

This method is used to reset the component's properties and configuration settings to their default values.

SetInputStream Method (PDFEncrypt Component)

Sets the stream containing the PDF document to process.

Syntax

• C#
• VB.NET

public void SetInputStream(System.IO.Stream inputStream);

Async Version
public async Task SetInputStream(System.IO.Stream inputStream);
public async Task SetInputStream(System.IO.Stream inputStream, CancellationToken cancellationToken);

Public Sub SetInputStream(ByVal InputStream As System.IO.Stream)

Async Version
Public Sub SetInputStream(ByVal InputStream As System.IO.Stream) As Task
Public Sub SetInputStream(ByVal InputStream As System.IO.Stream, cancellationToken As CancellationToken) As Task

Remarks

This method is used to set the stream from which the component will read the PDF document to be processed. If an input stream is set before the component attempts to perform operations on the document, the component will read the data from the input stream instead of from the InputFile or InputData properties.

Note: It may be useful to additionally set the CloseInputStreamAfterProcessing configuration setting to true when using input streams.

SetOutputStream Method (PDFEncrypt Component)

Sets the stream to write the processed document to.

Syntax

• C#
• VB.NET

public void SetOutputStream(System.IO.Stream outputStream);

Async Version
public async Task SetOutputStream(System.IO.Stream outputStream);
public async Task SetOutputStream(System.IO.Stream outputStream, CancellationToken cancellationToken);

Public Sub SetOutputStream(ByVal OutputStream As System.IO.Stream)

Async Version
Public Sub SetOutputStream(ByVal OutputStream As System.IO.Stream) As Task
Public Sub SetOutputStream(ByVal OutputStream As System.IO.Stream, cancellationToken As CancellationToken) As Task

Remarks

This method is used to set the stream to which the component will write the resulting PDF document. If an output stream is set before the component attempts to perform operations on the document, the component will write the data to the output stream instead of writing to OutputFile or populating OutputData.

Note: It may be useful to additionally set the CloseOutputStreamAfterProcessing configuration setting to true when using output streams.

Error Event (PDFEncrypt Component)

Fired when information is available about errors during data delivery.

Syntax

• C#
• VB.NET

public event OnErrorHandler OnError;

public delegate void OnErrorHandler(object sender, PDFEncryptErrorEventArgs e);

public class PDFEncryptErrorEventArgs : EventArgs {
  public int ErrorCode { get; }
  public string Description { get; }
}

Public Event OnError As OnErrorHandler

Public Delegate Sub OnErrorHandler(sender As Object, e As PDFEncryptErrorEventArgs)

Public Class PDFEncryptErrorEventArgs Inherits EventArgs
  Public ReadOnly Property ErrorCode As Integer
  Public ReadOnly Property Description As String
End Class

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the component throws an exception.

The ErrorCode parameter contains an error code, and the Description parameter contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

Log Event (PDFEncrypt Component)

Fired once for each log message.

Syntax

• C#
• VB.NET

public event OnLogHandler OnLog;

public delegate void OnLogHandler(object sender, PDFEncryptLogEventArgs e);

public class PDFEncryptLogEventArgs : EventArgs {
  public int LogLevel { get; }
  public string Message { get; }
  public string LogType { get; }
}

Public Event OnLog As OnLogHandler

Public Delegate Sub OnLogHandler(sender As Object, e As PDFEncryptLogEventArgs)

Public Class PDFEncryptLogEventArgs Inherits EventArgs
  Public ReadOnly Property LogLevel As Integer
  Public ReadOnly Property Message As String
  Public ReadOnly Property LogType As String
End Class

Remarks

This event is fired once for each log message generated by the component. The verbosity is controlled by the LogLevel configuration setting.

The LogLevel parameter indicates the detail level of the message. Possible values are:

The Message parameter is the log message.

The LogType parameter identifies the type of log entry. Possible values are:

• CertValidator
• Font
• HTTP
• PDFInvalidSignature
• PDFRevocationInfo
• Timestamp
• TSL

Password Event (PDFEncrypt Component)

Fired when the component detects that the PDF document is encrypted with a password.

Syntax

• C#
• VB.NET

public event OnPasswordHandler OnPassword;

public delegate void OnPasswordHandler(object sender, PDFEncryptPasswordEventArgs e);

public class PDFEncryptPasswordEventArgs : EventArgs {
  public bool Available { get; }
  public bool Cancel { get; set; }
}

Public Event OnPassword As OnPasswordHandler

Public Delegate Sub OnPasswordHandler(sender As Object, e As PDFEncryptPasswordEventArgs)

Public Class PDFEncryptPasswordEventArgs Inherits EventArgs
  Public ReadOnly Property Available As Boolean
  Public Property Cancel As Boolean
End Class

Remarks

This event is fired during document processing to report that the document is encrypted with a password. It may be used to supply the correct decryption password to the Password property.

The Available parameter indicates whether the decryption password is already available to the component or still needs to be set. If this parameter is set to false, the correct password must be provided for the decryption attempt to succeed.

The Cancel parameter determines whether the component will stop firing this event to request a password.

RecipientInfo Event (PDFEncrypt Component)

Fired for each recipient certificate of the encrypted PDF document.

Syntax

• C#
• VB.NET

public event OnRecipientInfoHandler OnRecipientInfo;

public delegate void OnRecipientInfoHandler(object sender, PDFEncryptRecipientInfoEventArgs e);

public class PDFEncryptRecipientInfoEventArgs : EventArgs {
  public string Issuer { get; }
  public string SerialNumber { get; }
  public string SubjectKeyIdentifier { get; }
  public bool Available { get; }
  public bool Cancel { get; set; }
}

Public Event OnRecipientInfo As OnRecipientInfoHandler

Public Delegate Sub OnRecipientInfoHandler(sender As Object, e As PDFEncryptRecipientInfoEventArgs)

Public Class PDFEncryptRecipientInfoEventArgs Inherits EventArgs
  Public ReadOnly Property Issuer As String
  Public ReadOnly Property SerialNumber As String
  Public ReadOnly Property SubjectKeyIdentifier As String
  Public ReadOnly Property Available As Boolean
  Public Property Cancel As Boolean
End Class

Remarks

This event is fired during document processing for each recipient certificate that the document has been encrypted for (if applicable). It may be used to identify the certificate(s) to load and supply to the DecryptionCert property.

The Issuer parameter specifies the subject of the issuer certificate.

The SerialNumber parameter specifies the serial number of the encryption certificate.

The SubjectKeyIdentifier parameter specifies the X.509 subjectKeyIdentifier extension value of the encryption certificate, encoded as a hex string.

The Available parameter indicates whether the decryption certificate is already available to the component or still needs to be set. If this parameter is set to false, the correct certificate must be provided for the decryption attempt to succeed.

The Cancel parameter determines whether the component will stop firing this event to request a certificate.

Note: The document may be encrypted with more than one certificate (or have "more than one recipient"), in which case each certificate will cause its own invocation of this event.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

Fields

Constructors

• C#
• VB.NET

public Certificate();

Public Certificate()

• C#
• VB.NET

public Certificate(string certificateFile);

Public Certificate(ByVal CertificateFile As String)

• C#
• VB.NET

public Certificate(byte[] encoded);

Public Certificate(ByVal Encoded As Byte())

• C#
• VB.NET

public Certificate(CertStoreTypes storeType, string store, string storePassword, string subject);

Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Subject As String)

• C#
• VB.NET

public Certificate(CertStoreTypes storeType, string store, string storePassword, string subject, string configurationString);

Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Subject As String, ByVal ConfigurationString As String)

• C#
• VB.NET

public Certificate(CertStoreTypes storeType, string store, string storePassword, byte[] encoded);

Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As String, ByVal StorePassword As String, ByVal Encoded As Byte())

• C#
• VB.NET

public Certificate(CertStoreTypes storeType, byte[] store, string storePassword, string subject);

Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As Byte(), ByVal StorePassword As String, ByVal Subject As String)

• C#
• VB.NET

public Certificate(CertStoreTypes storeType, byte[] store, string storePassword, string subject, string configurationString);

Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As Byte(), ByVal StorePassword As String, ByVal Subject As String, ByVal ConfigurationString As String)

• C#
• VB.NET

public Certificate(CertStoreTypes storeType, byte[] store, string storePassword, byte[] encoded);

Public Certificate(ByVal StoreType As CertStoreTypes, ByVal Store As Byte(), ByVal StorePassword As String, ByVal Encoded As Byte())

Config Settings (PDFEncrypt Component)

PDFEncrypt Config Settings

Base Config Settings

Trappable Errors (PDFEncrypt Component)

PDFEncrypt Errors

PDF Errors

Parsing Errors