A class that is used to encrypt a PDF file and set document permissions on the PDF file. More...

#include <PdfEncrypt.h>

Inherited by PoDoFo::PdfEncryptMD5Base.

Public Member Functions
void	EnsureEncryptionInitialized (const PdfString &documentId, PdfEncryptContext &context)
	Ensure encryption key and /O, /U, /OE, /UE values are initialized. More...

void	Authenticate (const std::string_view &password, const PdfString &documentId, PdfEncryptContext &context) const
	Tries to authenticate a user using either the user or owner password. More...

virtual void	CreateEncryptionDictionary (PdfDictionary &dictionary) const =0
	Fill all keys into a encryption dictionary. More...

virtual std::unique_ptr< InputStream >	CreateEncryptionInputStream (InputStream &inputStream, size_t inputLen, PdfEncryptContext &context, const PdfReference &objref) const =0
	Create an InputStream that decrypts all data read from it using the current settings of the PdfEncrypt object. More...

virtual std::unique_ptr< OutputStream >	CreateEncryptionOutputStream (OutputStream &outputStream, PdfEncryptContext &context, const PdfReference &objref) const =0
	Create an OutputStream that encrypts all data written to it using the current settings of the PdfEncrypt object. More...

PdfEncryptionAlgorithm	GetEncryptAlgorithm () const
	Get the encryption algorithm of this object. More...

bool	IsOwnerPasswordSet () const
	Checks if an owner password is set. More...

bool	IsPrintAllowed () const
	Checks if printing this document is allowed. More...

bool	IsEditAllowed () const
	Checks if modifying this document (besides annotations, form fields or changing pages) is allowed. More...

bool	IsCopyAllowed () const
	Checks if text and graphics extraction is allowed. More...

bool	IsEditNotesAllowed () const
	Checks if it is allowed to add or modify annotations or form fields Every PDF consuming applications has to adhere this value! More...

bool	IsFillAndSignAllowed () const
	Checks if it is allowed to fill in existing form or signature fields Every PDF consuming applications has to adhere this value! More...

bool	IsAccessibilityAllowed () const
	Checks if it is allowed to extract text and graphics to support users with disabilities Every PDF consuming applications has to adhere this value! More...

bool	IsDocAssemblyAllowed () const
	Checks if it is allowed to insert, create, rotate, delete pages or add bookmarks Every PDF consuming applications has to adhere this value! More...

bool	IsHighPrintAllowed () const
	Checks if it is allowed to print a high quality version of this document Every PDF consuming applications has to adhere this value! More...

void	EncryptTo (charbuff &out, const bufferview &view, PdfEncryptContext &context, const PdfReference &objref) const
	Encrypt a character span.

void	DecryptTo (charbuff &out, const bufferview &view, PdfEncryptContext &context, const PdfReference &objref) const
	Decrypt a character span.

virtual size_t	CalculateStreamLength (size_t length) const =0
	Calculate stream size.

virtual size_t	CalculateStreamOffset () const =0
	Calculate stream offset.

unsigned	GetKeyLengthBytes () const
	Get the encryption key length in bytes. More...

bufferview	GetUValue () const
	Get the U object value (user)

bufferview	GetOValue () const
	Get the O object value (owner)

PdfKeyLength	GetKeyLength () const
	Get the length of the encryption key in bits.

PdfPermissions	GetPValue () const
	Get the P object value (protection)

unsigned	GetRevision () const
	Get the revision number of the encryption method.

bool	IsMetadataEncrypted () const

bool	IsParsed () const

Static Public Member Functions
static std::unique_ptr< PdfEncrypt >	Create (const std::string_view &userPassword, const std::string_view &ownerPassword, PdfPermissions protection=PdfPermissions::Default, PdfEncryptionAlgorithm algorithm=PdfEncryptionAlgorithm::AESV2, PdfKeyLength keyLength=PdfKeyLength::Unknown)
	Create a PdfEncrypt object which can be used to encrypt a PDF file. More...

static std::unique_ptr< PdfEncrypt >	CreateFromObject (const PdfObject &obj)
	Initialize a PdfEncrypt object from an encryption dictionary in a PDF file. More...

static PdfEncryptionAlgorithm	GetEnabledEncryptionAlgorithms ()
	Retrieve the list of encryption algorithms that are used when loading a PDF document. More...

static bool	IsEncryptionEnabled (PdfEncryptionAlgorithm algorithm)
	Test if a certain encryption algorithm is enabled for loading PDF documents. More...

Protected Types
enum class	PdfRC4Revision { R2 = 2 , R3 = 3 }

Protected Member Functions
const unsigned char *	GetUValueRaw () const

const unsigned char *	GetOValueRaw () const

const std::string &	GetUserPassword () const

const std::string &	GetOwnerPassword () const

int64_t	GetPValueForSerialization () const

void	InitFromValues (PdfEncryptionAlgorithm algorithm, PdfKeyLength keyLength, unsigned char revision, PdfPermissions pValue, const bufferview &uValue, const bufferview &oValue, bool encryptedMetadata)
	Init from parsed values.

void	InitFromScratch (const std::string_view &userPassword, const std::string_view &ownerPassword, PdfEncryptionAlgorithm algorithm, PdfKeyLength keyLength, unsigned char revision, PdfPermissions pValue, bool encryptedMetadata)
	Init from scratch with user/owner password. More...

virtual void	Decrypt (const char inStr, size_t inLen, PdfEncryptContext &context, const PdfReference &objref, char outStr, size_t &outLen) const =0

virtual void	Encrypt (const char inStr, size_t inLen, PdfEncryptContext &context, const PdfReference &objref, char outStr, size_t outLen) const =0

virtual PdfAuthResult	Authenticate (const std::string_view &password, const std::string_view &documentId, PODOFO_CRYPT_CTX *ctx, unsigned char encryptionKey[32]) const =0

virtual void	GenerateEncryptionKey (const std::string_view &documentId, PdfAuthResult authResult, PODOFO_CRYPT_CTX *ctx, unsigned char uValue[48], unsigned char oValue[48], unsigned char encryptionKey[32])=0

bool	CheckKey (const unsigned char key1[32], const unsigned char key2[32]) const

Friends
class	PdfEncryptMD5Base

class	PdfEncryptAESV3

Detailed Description

A class that is used to encrypt a PDF file and set document permissions on the PDF file.

As a user of this class, you have only to instantiate a object of this class and pass it to PdfWriter, PdfMemDocument, PdfStreamedDocument or PdfImmediateWriter. You do not have to call any other method of this class. The above classes know how to handle encryption using PdfEncrypt.

Member Function Documentation

◆ Authenticate()

void PoDoFo::PdfEncrypt::Authenticate	(	const std::string_view &	password,
		const PdfString &	documentId,
		PdfEncryptContext &	context
	)		const

Tries to authenticate a user using either the user or owner password.

Parameters

password	owner or user password
documentId	the documentId of the PDF file

Returns: true if either the owner or user password matches password

◆ Create()

unique_ptr< PdfEncrypt > PdfEncrypt::Create	(	const std::string_view &	userPassword,
		const std::string_view &	ownerPassword,
		PdfPermissions	protection = `PdfPermissions::Default`,
		PdfEncryptionAlgorithm	algorithm = `PdfEncryptionAlgorithm::AESV2`,
		PdfKeyLength	keyLength = `PdfKeyLength::Unknown`
	)

static

Create a PdfEncrypt object which can be used to encrypt a PDF file.

Parameters

userPassword	the user password (if empty the user does not have to enter a password to open the document)
ownerPassword	the owner password
protection	several PdfPermissions values or'ed together to set the users permissions for this document
algorithm	the revision of the encryption algorithm to be used
keyLength	the length of the encryption key ranging from 40 to 128 bits (only used if algorithm == PdfEncryptAlgorithm::RC4V2)

See also: EnsureEncryptionInitialized with the documentID to generate the real encryption key using this information

◆ CreateEncryptionDictionary()

virtual void PoDoFo::PdfEncrypt::CreateEncryptionDictionary ( PdfDictionary & dictionary ) const

pure virtual

Fill all keys into a encryption dictionary.

This dictionary is usually added to the PDF files trailer under the /Encryption key.

Parameters

dictionary an empty dictionary which is filled with information about the used encryption algorithm

◆ CreateEncryptionInputStream()

virtual std::unique_ptr<InputStream> PoDoFo::PdfEncrypt::CreateEncryptionInputStream	(	InputStream &	inputStream,
		size_t	inputLen,
		PdfEncryptContext &	context,
		const PdfReference &	objref
	)		const

pure virtual

Create an InputStream that decrypts all data read from it using the current settings of the PdfEncrypt object.

Warning: Currently only RC4 based encryption is supported using output streams!

Parameters

inputStream the created InputStream reads all decrypted data to this input stream.

Returns: an InputStream that decrypts all data.

Implemented in PoDoFo::PdfEncryptRC4, and PoDoFo::PdfEncryptAESV2.

◆ CreateEncryptionOutputStream()

virtual std::unique_ptr<OutputStream> PoDoFo::PdfEncrypt::CreateEncryptionOutputStream	(	OutputStream &	outputStream,
		PdfEncryptContext &	context,
		const PdfReference &	objref
	)		const

pure virtual

Create an OutputStream that encrypts all data written to it using the current settings of the PdfEncrypt object.

Warning: Currently only RC4 based encryption is supported using output streams!

Parameters

outputStream the created OutputStream writes all encrypted data to this output stream.

Returns: a OutputStream that encrypts all data.

Implemented in PoDoFo::PdfEncryptRC4, and PoDoFo::PdfEncryptAESV2.

◆ CreateFromObject()

unique_ptr< PdfEncrypt > PdfEncrypt::CreateFromObject ( const PdfObject & obj )

static

Initialize a PdfEncrypt object from an encryption dictionary in a PDF file.

This is required for encrypting a PDF file, but handled internally in PdfParser for you.

Will use only encrypting algorithms that are enabled.

Parameters

obj	a PDF encryption dictionary

See also: GetEnabledEncryptionAlgorithms

◆ EnsureEncryptionInitialized()

void PdfEncrypt::EnsureEncryptionInitialized	(	const PdfString &	documentId,
		PdfEncryptContext &	context
	)

Ensure encryption key and /O, /U, /OE, /UE values are initialized.

Parameters

documentId the documentId of the current document

◆ GetEnabledEncryptionAlgorithms()

PdfEncryptionAlgorithm PdfEncrypt::GetEnabledEncryptionAlgorithms ( )

static

Retrieve the list of encryption algorithms that are used when loading a PDF document.

By default all algorithms are enabled.

See also: IsEncryptionEnabled; SetEnabledEncryptionAlgorithms

Returns: an or'ed together list of all enabled encryption algorithms

◆ GetEncryptAlgorithm()

PdfEncryptionAlgorithm PoDoFo::PdfEncrypt::GetEncryptAlgorithm ( ) const

inline

Get the encryption algorithm of this object.

Returns: the PdfEncryptAlgorithm of this object

◆ GetKeyLengthBytes()

unsigned PdfEncrypt::GetKeyLengthBytes ( ) const

Get the encryption key length in bytes.

Remarks: The maximum is 32 bytes

◆ InitFromScratch()

void PdfEncrypt::InitFromScratch	(	const std::string_view &	userPassword,
		const std::string_view &	ownerPassword,
		PdfEncryptionAlgorithm	algorithm,
		PdfKeyLength	keyLength,
		unsigned char	revision,
		PdfPermissions	pValue,
		bool	encryptedMetadata
	)

protected

Init from scratch with user/owner password.

Requires full initialization with EnsureEncryptionInitialized

◆ IsAccessibilityAllowed()

bool PdfEncrypt::IsAccessibilityAllowed ( ) const

Checks if it is allowed to extract text and graphics to support users with disabilities Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to extract text and graphics to support users with disabilities

See also: PdfEncrypt to set own document permissions.

◆ IsCopyAllowed()

bool PdfEncrypt::IsCopyAllowed ( ) const

Checks if text and graphics extraction is allowed.

Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to extract text and graphics from this document

See also: PdfEncrypt to set own document permissions.

◆ IsDocAssemblyAllowed()

bool PdfEncrypt::IsDocAssemblyAllowed ( ) const

Checks if it is allowed to insert, create, rotate, delete pages or add bookmarks Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to insert, create, rotate, delete pages or add bookmarks

See also: PdfEncrypt to set own document permissions.

◆ IsEditAllowed()

bool PdfEncrypt::IsEditAllowed ( ) const

Checks if modifying this document (besides annotations, form fields or changing pages) is allowed.

Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to modify this document

See also: PdfEncrypt to set own document permissions.

◆ IsEditNotesAllowed()

bool PdfEncrypt::IsEditNotesAllowed ( ) const

Checks if it is allowed to add or modify annotations or form fields Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to add or modify annotations or form fields

See also: PdfEncrypt to set own document permissions.

◆ IsEncryptionEnabled()

bool PdfEncrypt::IsEncryptionEnabled ( PdfEncryptionAlgorithm algorithm )

static

Test if a certain encryption algorithm is enabled for loading PDF documents.

Returns: true if the encryption algorithm is enabled

See also: GetEnabledEncryptionAlgorithms; SetEnabledEncryptionAlgorithms

◆ IsFillAndSignAllowed()

bool PdfEncrypt::IsFillAndSignAllowed ( ) const

Checks if it is allowed to fill in existing form or signature fields Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to fill in existing form or signature fields

See also: PdfEncrypt to set own document permissions.

◆ IsHighPrintAllowed()

bool PdfEncrypt::IsHighPrintAllowed ( ) const

Checks if it is allowed to print a high quality version of this document Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to print a high quality version of this document

See also: PdfEncrypt to set own document permissions.

◆ IsOwnerPasswordSet()

bool PdfEncrypt::IsOwnerPasswordSet ( ) const

Checks if an owner password is set.

An application reading PDF must adhere to permissions for printing, copying, etc., unless the owner password was used to open it.

Returns: true if the owner password is set, in which case IsPrintAllowed etc. should be ignored

See also: PdfEncrypt to set own document permissions.

◆ IsPrintAllowed()

bool PdfEncrypt::IsPrintAllowed ( ) const

Checks if printing this document is allowed.

Every PDF consuming applications has to adhere this value!

Returns: true if you are allowed to print this document

See also: PdfEncrypt to set own document permissions.

The documentation for this class was generated from the following files:

src/podofo/main/PdfEncrypt.h
src/podofo/main/PdfEncrypt.cpp

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Friends

Detailed Description

Member Function Documentation

◆ Authenticate()

◆ Create()

◆ CreateEncryptionDictionary()

◆ CreateEncryptionInputStream()

◆ CreateEncryptionOutputStream()

◆ CreateFromObject()

◆ EnsureEncryptionInitialized()

◆ GetEnabledEncryptionAlgorithms()

◆ GetEncryptAlgorithm()

◆ GetKeyLengthBytes()

◆ InitFromScratch()

◆ IsAccessibilityAllowed()

◆ IsCopyAllowed()

◆ IsDocAssemblyAllowed()

◆ IsEditAllowed()

◆ IsEditNotesAllowed()

◆ IsEncryptionEnabled()

◆ IsFillAndSignAllowed()

◆ IsHighPrintAllowed()

◆ IsOwnerPasswordSet()

◆ IsPrintAllowed()