PGPWriter Class

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The PGPWriter class protects data using PGP keys.

Syntax

class secureblackbox.PGPWriter

Remarks

PGPWriter lets you encrypt, sign, armor, and compress files and data in accordance with PGP standard.

PGPWriter supports all modern PGP keys and formats, from last-century PGP 2.6.x to the state-of-the art PGP 6. Single- and multi-file, as well as for-your-eyes-only PGP containers are supported.

Important note. Starting with SecureBlackbox 2024, PGPWriter and PGPReader fully support PGPv6 specification. Introduction of PGPv6 comes with certain upgrade of the default security settings used in these components. Although any projects that rely on earlier SecureBlackbox versions are likely to migrate to SecureBlackbox 2024 without any issues, the mentioned upgrade in security defaults may make protected files that your software produces incompatible with the software on the other end (particularly if that software is on the older scale of age).

While every care was taken to preserve interoperability wherever possible, some security settings could not be upgraded without the risk of affecting it. That said, none of the functionality was removed, so if you start encountering compatibility problems after upgrading to SecureBlackbox 2024, there is always a way back to the 'working' settings.

Please see the section at the end of this topic for the summary of differences between SBB 2022 and SBB 2024 in terms of security settings.

Preparing keys

Encryption and signing in PGP is done with asymmetric keys. Keys are normally stored in files called keyrings. More often that not they consist of a pair of files: a public keyring (e.g pubring.pkr) and a secret keyring (secring.skr), although there are exceptions. Sometimes, recipients provide senders with standalone public keys that they want them to encrypt data with.

Whichever form your keyring takes, use PGPKeyring to load it first. It is recommended to load all the keyring files that you have to make sure you have all the keys loaded. PGPKeyring can detect duplicate keys, so don't worry about loading the same key twice - any duplicates will be neatly merged together into one key object.

 
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  PGPKeyring keyring = new PGPKeyring();
  keyring.ImportFromFile("pubring.pkr");
  keyring.ImportFromFile("secring.skr");

Now that you've loaded the keyring files, it is time to identify the key(s) that you need to use and pass them to PGPWriter. The best way to do it may differ between environments. Among the options available are iterating over the whole keys collection of the PGPKeyring object, using its select method to filter keys by UserID, or just using the whole set of keys if loading a standalone key.

Whichever way you choose to select the keys, there are a few considerations that need to be taken into account. First, keep in mind that the keys collection contains both the primary keys and their subkeys. PGP is very flexible on how the 'key trees' can be formed, which means that keys from different vendors may use different key tree patterns.

The most commonly used key tree pattern is where the primary key is sign-only, and its only subkey is encrypt-only. However, there can be different arrangements: for example, there can be more than one subkey in the key tree, or the primary key can be used for encryption alongside the subkey. Please take extra care to figure out what kind of key tree you are dealing with, and select appropriate keys with that structure in mind.

The following properties of the key objects might be helpful in filtering the keys by their purpose:

• and properties of the key objects provide information on the key algorithm capabilities. If you are looking to encrypt data, a key or subkey with its CanEncrypt set to false can be safely excluded from the candidate list.
• and specify whether the key contains the public or private part of the keypair. If you are looking to sign data, keys with their IsSecret set to false can be discarded, as signing can only be done with private keys.
• specifies the key's expiration date. Expired keys can be ignored. This is often useful where the vendor updates their keys by issuing fresh subkeys while keeping older ones in the key tree.

Now that you've identified the appropriate keys, you can add them to the respective collections of PGPWriter: encrypting_keys and signing_keys. However, there is one important catch that you need to keep in mind.

Private PGP keys are typically protected with passwords. To be able to use them, you need to provide the valid password to the component. You can do that in one of the following two ways:

• By assigning the password to property. You can check whether the provided passphrase is valid using the property.
• By subscribing to on_key_passphrase_needed event and providing the password from within the event handler. This event will be fired for each private key for which no valid password was provided.

Configuring protection

Protection configuration if quite straightforward and encompasses adjustment of the following settings:

• Provide the input data via the input_file (or input_bytes) property.
• Provide the destination in output_file. If no output destination is provided, the output will be generated in output_bytes.
• Provide the filename for the file being protected in filename.
• Set encryption_algorithm and hash_algorithm, as (and if) required.
• Set compress to true if you would like the input compressed. You can tune up compression further with compression_algorithm and compression_level settings.
• Set armor if you would like the output to be base64-armored.

Protecting the file

You are all set now. Call the appropriate protection method to proceed with the file protection:

• encrypt: encrypt the input data with all the public keys provided in encrypting_keys.
• sign: sign the input data with all the private keys provided in signing_keys.
• encrypt_and_sign: encrypt the input data with all the public keys provided in encrypting_keys and sign it with all the private keys provided in signing_keys.
• clear_text_sign: sign the input data in email-like way with all the private keys provided in signing_keys. This method only works with textual ASCII data.

 
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  Writer.InputFile = "C:\files\input.txt";
  Writer.OutputFile = "C:\files\output.pgp";
  Writer.Filename = "input.txt";
  Writer.EncryptionAlgorithm = "AES256";
  Writer.SigningKeys.Add(Keyring.Keys[0]);
  Writer.EncryptingKeys.Add(Keyring.Keys[1]);
  Writer.EncryptAndSign();

Summary of changes in security defaults between SBB 2022 and SBB 2024

Protection type.

While the set of protection elements stayed the same, the meaning of the elements changed (deflated):

• pptNone: stayed the same
• pptLow in version 2024 corresponds to the protection settings that used to be marked as pptNormal in version 2022.
• pptNormal in version 2024 corresponds to the protection settings that used to be marked as pptHigh in version 2022.
• pptHigh has no equivalent level of protection in version 2022. It corresponds to strong authenticated encryption (AEAD) and KDF introduced in PGP v5 and v6.

Cryptographic algorithms

The default value of hash_algorithm has changed from SHA1 (SBB 2022) to SHA256 (SBB 2024). The default value of encryption_algorithm changed from CAST5 (SBB 2022) to AES128 (SBB 2024).

This change applies throughout all the PGP components.

UseNewFeatures configuration setting

In SBB 2022 and earlier versions the meaning behind this configuration setting was about enforcing 'new' RFC4880 features, such as MDC packets for authenticated encryption and one-pass signatures.

In SBB 2024, this setting regained its 'new' connotation and applies to PGP v6 features such as AEAD encryption. Use this setting with care as older PGP implementations may struggle to process files protected with PGP v6 features.

Property List

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

Method List

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

Event List

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

Config Settings

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

armor Property

Specifies whether the data should be armored.

Syntax

def get_armor() -> bool: ...
def set_armor(value: bool) -> None: ...

armor = property(get_armor, set_armor)

Default Value

FALSE

Remarks

Switch this property on to armor the protected data by encoding it in base64 and enveloping with BEGIN and END markings.

armor_boundary Property

A boundary to put around the base64 armor.

Syntax

def get_armor_boundary() -> str: ...
def set_armor_boundary(value: str) -> None: ...

armor_boundary = property(get_armor_boundary, set_armor_boundary)

Default Value

""

Remarks

Use this property to specify the boundary to put around the base64 armor. If set to 'PGP MESSAGE', the armored data will be enveloped with '-----BEGIN PGP MESSAGE-----' and '-----END PGP MESSAGE-----' lines.

This property only makes sense if armor is set True.

armor_headers Property

Additional headers to include with the armored message.

Syntax

def get_armor_headers() -> str: ...
def set_armor_headers(value: str) -> None: ...

armor_headers = property(get_armor_headers, set_armor_headers)

Default Value

""

Remarks

Use this property to specify additional headers to be included with the armored message.

Assign this property with a multi-line text, with each line being of "header: value" form (without quotes).

compress Property

Whether to compress the data before encrypting it.

Syntax

def get_compress() -> bool: ...
def set_compress(value: bool) -> None: ...

compress = property(get_compress, set_compress)

Default Value

FALSE

Remarks

Set this property to True to compress the data before encryption. Use compression_algorithm and compression_level to tune up compression parameters.

compression_algorithm Property

The compression algorithm to use.

Syntax

def get_compression_algorithm() -> str: ...
def set_compression_algorithm(value: str) -> None: ...

compression_algorithm = property(get_compression_algorithm, set_compression_algorithm)

Default Value

"Uncompressed"

Remarks

Use this property to specify the compression algorithm to use before encrypting the data. This property only makes sense if compress is True.

compression_level Property

The compression level to use.

Syntax

def get_compression_level() -> int: ...
def set_compression_level(value: int) -> None: ...

compression_level = property(get_compression_level, set_compression_level)

Default Value

0

Remarks

Use this property to specify the compression level, from 1 (fastest) to 9 (best).

encrypting_key_count Property

The number of records in the EncryptingKey arrays.

Syntax

def get_encrypting_key_count() -> int: ...
def set_encrypting_key_count(value: int) -> None: ...

encrypting_key_count = property(get_encrypting_key_count, set_encrypting_key_count)

Default Value

0

Remarks

This property controls the size of the following arrays:

• encrypting_key_handle
• encrypting_key_key_fp
• encrypting_key_key_id
• encrypting_key_username

The array indices start at 0 and end at encrypting_key_count - 1.

encrypting_key_handle Property

Allows to get or set a 'handle', a unique identifier of the underlying property object.

Syntax

def get_encrypting_key_handle(encrypting_key_index: int) -> int: ...
def set_encrypting_key_handle(encrypting_key_index: int, value: int) -> None: ...

Default Value

0

Remarks

Allows to get or set a 'handle', a unique identifier of the underlying property object. Use this property to assign objects of the same type in a quicker manner, without copying them fieldwise.

When you pass a handle of one object to another, the source object is copied to the destination rather than assigned. It is safe to get rid of the original object after such operation.

 
 Copy
  pdfSigner.setSigningCertHandle(certMgr.getCertHandle());

The encrypting_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the encrypting_key_count property.

encrypting_key_key_fp Property

The 20-byte fingerprint (hash value) of this key.

Syntax

def get_encrypting_key_key_fp(encrypting_key_index: int) -> str: ...

Default Value

""

Remarks

The 20-byte fingerprint (hash value) of this key.

KeyFP could be used to distinguish two keys with the same KeyID.

The encrypting_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the encrypting_key_count property.

This property is read-only.

encrypting_key_key_id Property

Contains a 8-byte key identifier.

Syntax

def get_encrypting_key_key_id(encrypting_key_index: int) -> str: ...

Default Value

""

Remarks

Contains a 8-byte key identifier.

It is quite rare that IDs of two keys collide. If that happens, their fingerprints (KeyFP) can be used for distinguish between the keys. Please note that many PGP implementations show only 4 lowest bytes of the KeyID to the user.

The encrypting_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the encrypting_key_count property.

This property is read-only.

encrypting_key_username Property

Specifies the name of the user bound to this key.

Syntax

def get_encrypting_key_username(encrypting_key_index: int) -> str: ...

Default Value

""

Remarks

Specifies the name of the user bound to this key.

The PGP username is typically represented with a full name and an email address, but generally can be any non-empty string.

The encrypting_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the encrypting_key_count property.

This property is read-only.

encryption_algorithm Property

A symmetric algorithm to use for data encryption.

Syntax

def get_encryption_algorithm() -> str: ...
def set_encryption_algorithm(value: str) -> None: ...

encryption_algorithm = property(get_encryption_algorithm, set_encryption_algorithm)

Default Value

"AES128"

Remarks

Use this property to specify a symmetric algorithm to use for data encryption.

external_crypto_async_document_id Property

Specifies an optional document ID for SignAsyncBegin() and SignAsyncEnd() calls.

Syntax

def get_external_crypto_async_document_id() -> str: ...
def set_external_crypto_async_document_id(value: str) -> None: ...

external_crypto_async_document_id = property(get_external_crypto_async_document_id, set_external_crypto_async_document_id)

Default Value

""

Remarks

Specifies an optional document ID for SignAsyncBegin() and SignAsyncEnd() calls.

Use this property when working with multi-signature DCAuth requests and responses to uniquely identify documents signed within a larger batch. On the completion stage, this value helps the signing component identify the correct signature in the returned batch of responses.

If using batched requests, make sure to set this property to the same value on both the pre-signing (SignAsyncBegin) and completion (SignAsyncEnd) stages.

external_crypto_custom_params Property

Custom parameters to be passed to the signing service (uninterpreted).

Syntax

def get_external_crypto_custom_params() -> str: ...
def set_external_crypto_custom_params(value: str) -> None: ...

external_crypto_custom_params = property(get_external_crypto_custom_params, set_external_crypto_custom_params)

Default Value

""

Remarks

Custom parameters to be passed to the signing service (uninterpreted).

external_crypto_data Property

Additional data to be included in the async state and mirrored back by the requestor.

Syntax

def get_external_crypto_data() -> str: ...
def set_external_crypto_data(value: str) -> None: ...

external_crypto_data = property(get_external_crypto_data, set_external_crypto_data)

Default Value

""

Remarks

Additional data to be included in the async state and mirrored back by the requestor.

external_crypto_external_hash_calculation Property

Specifies whether the message hash is to be calculated at the external endpoint.

Syntax

def get_external_crypto_external_hash_calculation() -> bool: ...
def set_external_crypto_external_hash_calculation(value: bool) -> None: ...

external_crypto_external_hash_calculation = property(get_external_crypto_external_hash_calculation, set_external_crypto_external_hash_calculation)

Default Value

FALSE

Remarks

Specifies whether the message hash is to be calculated at the external endpoint. Please note that this mode is not supported by the DCAuth class.

If set to true, the class will pass a few kilobytes of to-be-signed data from the document to the OnExternalSign event. This only applies when SignExternal() is called.

external_crypto_hash_algorithm Property

Specifies the request's signature hash algorithm.

Syntax

def get_external_crypto_hash_algorithm() -> str: ...
def set_external_crypto_hash_algorithm(value: str) -> None: ...

external_crypto_hash_algorithm = property(get_external_crypto_hash_algorithm, set_external_crypto_hash_algorithm)

Default Value

"SHA256"

Remarks

Specifies the request's signature hash algorithm.

external_crypto_key_id Property

The ID of the pre-shared key used for DC request authentication.

Syntax

def get_external_crypto_key_id() -> str: ...
def set_external_crypto_key_id(value: str) -> None: ...

external_crypto_key_id = property(get_external_crypto_key_id, set_external_crypto_key_id)

Default Value

""

Remarks

The ID of the pre-shared key used for DC request authentication.

Asynchronous DCAuth-driven communication requires that parties authenticate each other with a secret pre-shared cryptographic key. This provides an extra protection layer for the protocol and diminishes the risk of the private key becoming abused by foreign parties. Use this property to provide the pre-shared key identifier, and use external_crypto_key_secret to pass the key itself.

The same KeyID/KeySecret pair should be used on the DCAuth side for the signing requests to be accepted.

Note: The KeyID/KeySecret scheme is very similar to the AuthKey scheme used in various Cloud service providers to authenticate users.

Example:

 
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  signer.ExternalCrypto.KeyID = "MainSigningKey";
  signer.ExternalCrypto.KeySecret = "abcdef0123456789";

external_crypto_key_secret Property

The pre-shared key used for DC request authentication.

Syntax

def get_external_crypto_key_secret() -> str: ...
def set_external_crypto_key_secret(value: str) -> None: ...

external_crypto_key_secret = property(get_external_crypto_key_secret, set_external_crypto_key_secret)

Default Value

""

Remarks

The pre-shared key used for DC request authentication. This key must be set and match the key used by the DCAuth counterpart for the scheme to work.

Read more about configuring authentication in the external_crypto_key_id topic.

external_crypto_method Property

Specifies the asynchronous signing method.

Syntax

def get_external_crypto_method() -> int: ...
def set_external_crypto_method(value: int) -> None: ...

external_crypto_method = property(get_external_crypto_method, set_external_crypto_method)

Possible Values

0   # PKCS1
1   # PKCS7

Default Value

0

Remarks

Specifies the asynchronous signing method. This is typically defined by the DC server capabilities and setup.

Available options:

external_crypto_mode Property

Specifies the external cryptography mode.

Syntax

def get_external_crypto_mode() -> int: ...
def set_external_crypto_mode(value: int) -> None: ...

external_crypto_mode = property(get_external_crypto_mode, set_external_crypto_mode)

Possible Values

0   # Default
1   # Disabled
2   # Generic
3   # DCAuth
4   # DCAuthJSON

Default Value

0

Remarks

Specifies the external cryptography mode.

Available options:

external_crypto_public_key_algorithm Property

Provide the public key algorithm here if the certificate is not available on the pre-signing stage.

Syntax

def get_external_crypto_public_key_algorithm() -> str: ...
def set_external_crypto_public_key_algorithm(value: str) -> None: ...

external_crypto_public_key_algorithm = property(get_external_crypto_public_key_algorithm, set_external_crypto_public_key_algorithm)

Default Value

""

Remarks

Provide the public key algorithm here if the certificate is not available on the pre-signing stage.

file_name Property

Specifies the name of the file being protected.

Syntax

def get_file_name() -> str: ...
def set_file_name(value: str) -> None: ...

file_name = property(get_file_name, set_file_name)

Default Value

""

Remarks

Use this property to set the name of the file being protected, such as 'document.txt'. If Filename is empty or its value is "_CONSOLE", the data will be protected for-your-eyes-only, meaning the decryptor will only be able to read it on their screen, but not save.

fips_mode Property

Reserved.

Syntax

def get_fips_mode() -> bool: ...
def set_fips_mode(value: bool) -> None: ...

fips_mode = property(get_fips_mode, set_fips_mode)

Default Value

FALSE

Remarks

This property is reserved for future use.

hash_algorithm Property

The hash algorithm to use for signing.

Syntax

def get_hash_algorithm() -> str: ...
def set_hash_algorithm(value: str) -> None: ...

hash_algorithm = property(get_hash_algorithm, set_hash_algorithm)

Default Value

""

Remarks

Use this property to specify the hash algorithm to use for calculating signatures.

input_bytes Property

Use this property to pass the input to class in byte array form.

Syntax

def get_input_bytes() -> bytes: ...
def set_input_bytes(value: bytes) -> None: ...

input_bytes = property(get_input_bytes, set_input_bytes)

Remarks

Assign a byte array containing the data to be processed to this property.

input_file Property

Provides a filename of a file to process.

Syntax

def get_input_file() -> str: ...
def set_input_file(value: str) -> None: ...

input_file = property(get_input_file, set_input_file)

Default Value

""

Remarks

Use this property to provide a path to the file to be encrypted and/or signed.

If you assign this property with a directory name, all the files contained in the directory will be packed into the resulting protected file.

input_is_text Property

Whether the input data is text.

Syntax

def get_input_is_text() -> bool: ...
def set_input_is_text(value: bool) -> None: ...

input_is_text = property(get_input_is_text, set_input_is_text)

Default Value

FALSE

Remarks

Set this property to true to indicate that the supplied data should be treated as text.

output_bytes Property

Use this property to read the output the class object has produced.

Syntax

def get_output_bytes() -> bytes: ...

output_bytes = property(get_output_bytes, None)

Remarks

Read the contents of this property after the operation has completed to read the produced output. This property will only be set if the output_file and output_stream properties had not been assigned.

This property is read-only.

output_file Property

The file where the encrypted and/or signed data will be saved.

Syntax

def get_output_file() -> str: ...
def set_output_file(value: str) -> None: ...

output_file = property(get_output_file, set_output_file)

Default Value

""

Remarks

Use this property to provide a path to the file where the class should store the encrypted and/or signed data.

passphrase Property

The encryption password.

Syntax

def get_passphrase() -> str: ...
def set_passphrase(value: str) -> None: ...

passphrase = property(get_passphrase, set_passphrase)

Default Value

""

Remarks

Use this property to provide the encryption password. If an encryption password is used, no key will be needed to decrypt the data.

profile Property

Specifies a pre-defined profile to apply when creating the signature.

Syntax

def get_profile() -> str: ...
def set_profile(value: str) -> None: ...

profile = property(get_profile, set_profile)

Default Value

""

Remarks

Advanced signatures come in many variants, which are often defined by parties that needs to process them or by local standards. SecureBlackbox profiles are sets of pre-defined configurations which correspond to particular signature variants. By specifying a profile, you are pre-configuring the component to make it produce the signature that matches the configuration corresponding to that profile.

protection Property

Specifies a password protection level.

Syntax

def get_protection() -> int: ...
def set_protection(value: int) -> None: ...

protection = property(get_protection, set_protection)

Possible Values

0   # None
1   # Low
2   # Normal
3   # High

Default Value

0

Remarks

This property specifies the complexity of key derivation function for password-protected documents.

Allowed values:

signing_key_count Property

The number of records in the SigningKey arrays.

Syntax

def get_signing_key_count() -> int: ...
def set_signing_key_count(value: int) -> None: ...

signing_key_count = property(get_signing_key_count, set_signing_key_count)

Default Value

0

Remarks

This property controls the size of the following arrays:

• signing_key_handle
• signing_key_key_fp
• signing_key_key_id
• signing_key_passphrase
• signing_key_passphrase_valid
• signing_key_username

The array indices start at 0 and end at signing_key_count - 1.

signing_key_handle Property

Allows to get or set a 'handle', a unique identifier of the underlying property object.

Syntax

def get_signing_key_handle(signing_key_index: int) -> int: ...
def set_signing_key_handle(signing_key_index: int, value: int) -> None: ...

Default Value

0

Remarks

Allows to get or set a 'handle', a unique identifier of the underlying property object. Use this property to assign objects of the same type in a quicker manner, without copying them fieldwise.

When you pass a handle of one object to another, the source object is copied to the destination rather than assigned. It is safe to get rid of the original object after such operation.

 
 Copy
  pdfSigner.setSigningCertHandle(certMgr.getCertHandle());

The signing_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the signing_key_count property.

signing_key_key_fp Property

The 20-byte fingerprint (hash value) of this key.

Syntax

def get_signing_key_key_fp(signing_key_index: int) -> str: ...

Default Value

""

Remarks

The 20-byte fingerprint (hash value) of this key.

KeyFP could be used to distinguish two keys with the same KeyID.

The signing_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the signing_key_count property.

This property is read-only.

signing_key_key_id Property

Contains a 8-byte key identifier.

Syntax

def get_signing_key_key_id(signing_key_index: int) -> str: ...

Default Value

""

Remarks

Contains a 8-byte key identifier.

It is quite rare that IDs of two keys collide. If that happens, their fingerprints (KeyFP) can be used for distinguish between the keys. Please note that many PGP implementations show only 4 lowest bytes of the KeyID to the user.

The signing_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the signing_key_count property.

This property is read-only.

signing_key_passphrase Property

The key protection password.

Syntax

def get_signing_key_passphrase(signing_key_index: int) -> str: ...
def set_signing_key_passphrase(signing_key_index: int, value: str) -> None: ...

Default Value

""

Remarks

The key protection password.

The signing_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the signing_key_count property.

signing_key_passphrase_valid Property

Use this property to check whether the specified Passphrase is valid and can be used to unlock the secret key.

Syntax

def get_signing_key_passphrase_valid(signing_key_index: int) -> bool: ...

Default Value

FALSE

Remarks

Use this property to check whether the specified signing_key_passphrase is valid and can be used to unlock the secret key.

The signing_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the signing_key_count property.

This property is read-only.

signing_key_username Property

Specifies the name of the user bound to this key.

Syntax

def get_signing_key_username(signing_key_index: int) -> str: ...

Default Value

""

Remarks

Specifies the name of the user bound to this key.

The PGP username is typically represented with a full name and an email address, but generally can be any non-empty string.

The signing_key_index parameter specifies the index of the item in the array. The size of the array is controlled by the signing_key_count property.

This property is read-only.

timestamp Property

The date and time of the last modification of the protected data file (in UTC).

Syntax

def get_timestamp() -> str: ...
def set_timestamp(value: str) -> None: ...

timestamp = property(get_timestamp, set_timestamp)

Default Value

""

Remarks

Use this property to set a timestamp for the data being protected.

clear_text_sign Method

Creates a cleartext signature over the provided data.

Syntax

def clear_text_sign() -> None: ...

Remarks

Call this method to create a cleartext signature over the provided data buffer (input_bytes). Only textual data can be signed in cleartext.

Pass the signing key(s) via signing_keys property.

config Method

Sets or retrieves a configuration setting.

Syntax

def config(configuration_string: str) -> str: ...

Remarks

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

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, 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.

do_action Method

Performs an additional action.

Syntax

def do_action(action_id: str, action_params: str) -> str: ...

Remarks

do_action is a generic method available in every class. It is used to perform an additional action introduced after the product major release. The list of actions is not fixed, and may be flexibly extended over time.

The unique identifier (case insensitive) of the action is provided in the ActionID parameter.

ActionParams contains the value of a single parameter, or a list of multiple parameters for the action in the form of PARAM1=VALUE1;PARAM2=VALUE2;....

Common ActionIDs:

encrypt Method

Encrypts data.

Syntax

def encrypt() -> None: ...

Remarks

Use this method to encrypt input data from a byte array (input_bytes), a file (input_file) or a stream (input_stream) and get the protected message in another byte array (output_bytes), or another file (output_file), or another stream (output_stream).

Specify encryption keys in encrypting_keys property, and/or encryption password via passphrase property.

encrypt_and_sign Method

Encrypts and signs data.

Syntax

def encrypt_and_sign() -> None: ...

Remarks

Use this method to encrypt and sign a byte array (input_bytes), a file (input_file) or a stream (input_stream) and get the protected message in another byte array (output_bytes), or another file (output_file), or another stream (output_stream).

Specify encryption keys in encrypting_keys property, and/or encryption password via passphrase property. Use signing_keys to provide the signing keys.

Please note that you might need to provide a passphrase to decrypt your signing key. This can be done via on_key_passphrase_needed event, or by assigning the passphrase to the key object's Passphrase property.

reset Method

Resets the class settings.

Syntax

def reset() -> None: ...

Remarks

reset is a generic method available in every class.

sign Method

Signs data.

Syntax

def sign(detached: bool) -> None: ...

Remarks

Use this method to sign a byte array (input_bytes), a file (input_file) or a stream (input_stream) and get the signed message in another byte array (output_bytes), or another file (output_file), or another stream (output_stream).

Use signing_keys to provide the signing keys.

Please note that you might need to provide a passphrase to decrypt your signing key. This can be done via on_key_passphrase_needed event, or by assigning the passphrase to the key object's Passphrase property.

on_error Event

Information about errors during PGP encryption.

Syntax

class PGPWriterErrorEventParams(object):
  @property
  def error_code() -> int: ...

  @property
  def description() -> str: ...

# In class PGPWriter:
@property
def on_error() -> Callable[[PGPWriterErrorEventParams], None]: ...
@on_error.setter
def on_error(event_hook: Callable[[PGPWriterErrorEventParams], None]) -> None: ...

Remarks

The event is fired in case of exceptional conditions during data encryption or signing.

ErrorCode contains an error code and Description contains a textual description of the error.

on_external_sign Event

Handles remote or external signing initiated by the SignExternal method or other source.

Syntax

class PGPWriterExternalSignEventParams(object):
  @property
  def operation_id() -> str: ...

  @property
  def hash_algorithm() -> str: ...

  @property
  def pars() -> str: ...

  @property
  def data() -> str: ...

  @property
  def signed_data() -> str: ...
  @signed_data.setter
  def signed_data(value) -> None: ...

# In class PGPWriter:
@property
def on_external_sign() -> Callable[[PGPWriterExternalSignEventParams], None]: ...
@on_external_sign.setter
def on_external_sign(event_hook: Callable[[PGPWriterExternalSignEventParams], None]) -> None: ...

Remarks

Assign a handler to this event if you need to delegate a low-level signing operation to an external, remote, or custom signing engine. Depending on the settings, the handler will receive a hashed or unhashed value to be signed.

The event handler must pass the value of Data to the signer, obtain the signature, and pass it back to the class via the SignedData parameter.

OperationId provides a comment about the operation and its origin. It depends on the exact class being used, and may be empty. HashAlgorithm specifies the hash algorithm being used for the operation, and Pars contains algorithm-dependent parameters.

The class uses base16 (hex) encoding for the Data, SignedData, and Pars parameters. If your signing engine uses a different input and output encoding, you may need to decode and/or encode the data before and/or after the signing.

A sample MD5 hash encoded in base16: a0dee2a0382afbb09120ffa7ccd8a152 - lower case base16 A0DEE2A0382AFBB09120FFA7CCD8A152 - upper case base16

A sample event handler that uses the .NET RSACryptoServiceProvider class may look like the following:

 
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signer.OnExternalSign += (s, e) =>
{
       var cert = new X509Certificate2("cert.pfx", "", X509KeyStorageFlags.Exportable);
       var key = (RSACryptoServiceProvider)cert.PrivateKey;

       var dataToSign = e.Data.FromBase16String();
       var signedData = key.SignHash(dataToSign, "2.16.840.1.101.3.4.2.1");
       e.SignedData = signedData.ToBase16String();
};

on_key_passphrase_needed Event

Requests a key protection password from the application.

Syntax

class PGPWriterKeyPassphraseNeededEventParams(object):
  @property
  def key_id() -> str: ...

  @property
  def user_id() -> str: ...

  @property
  def main_key() -> bool: ...

  @property
  def passphrase() -> str: ...
  @passphrase.setter
  def passphrase(value) -> None: ...

  @property
  def skip() -> bool: ...
  @skip.setter
  def skip(value) -> None: ...

# In class PGPWriter:
@property
def on_key_passphrase_needed() -> Callable[[PGPWriterKeyPassphraseNeededEventParams], None]: ...
@on_key_passphrase_needed.setter
def on_key_passphrase_needed(event_hook: Callable[[PGPWriterKeyPassphraseNeededEventParams], None]) -> None: ...

Remarks

The class fires this event to request a secret key passphrase from the application. Note that this event asks for a key protection passphrase rather than a message protection passphrase. The class fires it when it attempts to use a secret key to sign the data.

This event is fired for every protected secret key residing in signing_keys. KeyID specifies the key for which the password is requested, and UserID identifies its user. MainKey tells whether the key is a master key or a subkey.

The handler should provide password via the Passphrase parameter, or set Skip to True to skip this key.

For each key KeyPassphraseNeeded is called in a loop until the correct password is provided or the maximum number of password attempts reached.

on_notification Event

This event notifies the application about an underlying control flow event.

Syntax

class PGPWriterNotificationEventParams(object):
  @property
  def event_id() -> str: ...

  @property
  def event_param() -> str: ...

# In class PGPWriter:
@property
def on_notification() -> Callable[[PGPWriterNotificationEventParams], None]: ...
@on_notification.setter
def on_notification(event_hook: Callable[[PGPWriterNotificationEventParams], None]) -> None: ...

Remarks

The class fires this event to let the application know about some event, occurrence, or milestone in the class. For example, it may fire to report completion of the document processing. The list of events being reported is not fixed, and may be flexibly extended over time.

The unique identifier of the event is provided in the EventID parameter. EventParam contains any parameters accompanying the occurrence. Depending on the type of the class, the exact action it is performing, or the document being processed, one or both may be omitted.

on_progress Event

Reports the progress of the decryption operation.

Syntax

class PGPWriterProgressEventParams(object):
  @property
  def current() -> int: ...

  @property
  def total() -> int: ...

  @property
  def cancel() -> bool: ...
  @cancel.setter
  def cancel(value) -> None: ...

# In class PGPWriter:
@property
def on_progress() -> Callable[[PGPWriterProgressEventParams], None]: ...
@on_progress.setter
def on_progress(event_hook: Callable[[PGPWriterProgressEventParams], None]) -> None: ...

Remarks

The class fires this event repeatedly to report the progress of the file protection operation.

Current indicates the amount of processed data in bytes, and Total is the total number of bytes to be processed. Use Cancel to terminate the protection process.

PGPWriter Config Settings

PGPWriter Config Settings

Base Config Settings

 
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PKICache=certificate,crl,ocsp

 
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PKICachePath=C:\Temp\cache

 
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Config("XMLRDNDescriptorName[OID]=PrimaryName,Alias1,Alias2");

 
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Config("XMLRDNDescriptorName[2.5.4.5]=SERIALNUMBER");

 
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Config("XMLRDNDescriptorName[1.2.840.113549.1.9.1]=E,EMAIL,EMAILADDRESS");

PGPWriter Errors

PGPWriter Errors