SymmetricCipher Class Reference

Interface for one direction (encryption or decryption) of a stream cipher or cipher mode. More...

Inheritance diagram for SymmetricCipher:
SimpleKeyingInterface StreamTransformation Algorithm Clonable CipherModeBase Weak1::ARC4_Base BlockOrientedCipherModeBase ModePolicyCommonTemplate< POLICY_INTERFACE > ModePolicyCommonTemplate< AdditiveCipherAbstractPolicy > ModePolicyCommonTemplate< CFB_CipherAbstractPolicy > Weak1::MARC4_Base CBC_ModeBase ECB_OneWay CTR_ModePolicy OFB_ModePolicy CFB_ModePolicy CBC_Decryption CBC_Encryption AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > CBC_CTS_Decryption CBC_CTS_Encryption AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > > ConcretePolicyHolder< Empty, AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > > > CipherModeFinalTemplate_ExternalCipher< ConcretePolicyHolder< Empty, AdditiveCipherTemplate< AbstractPolicyHolder< AdditiveCipherAbstractPolicy, CTR_ModePolicy > > > >

List of all members.

Public Types

enum  IV_Requirement {
  UNIQUE_IV = 0, RANDOM_IV, UNPREDICTABLE_RANDOM_IV, INTERNALLY_GENERATED_IV,
  NOT_RESYNCHRONIZABLE
}
 

Provides IV requirements as an enumerated value.

More...

Public Member Functions

virtual size_t MinKeyLength () const =0
 Returns smallest valid key length in bytes.
virtual size_t MaxKeyLength () const =0
 Returns largest valid key length in bytes.
virtual size_t DefaultKeyLength () const =0
 Returns default (recommended) key length in bytes.
virtual size_t GetValidKeyLength (size_t n) const =0
virtual bool IsValidKeyLength (size_t keylength) const
 Returns whether keylength is a valid key length.
virtual void SetKey (const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
 Sets or reset the key of this object.
void SetKeyWithRounds (const byte *key, size_t length, int rounds)
 Sets or reset the key of this object.
void SetKeyWithIV (const byte *key, size_t length, const byte *iv, size_t ivLength)
 Sets or reset the key of this object.
void SetKeyWithIV (const byte *key, size_t length, const byte *iv)
 Sets or reset the key of this object.
virtual IV_Requirement IVRequirement () const =0
 returns the minimal requirement for secure IVs
bool IsResynchronizable () const
 returns whether the object can be resynchronized (i.e. supports initialization vectors)
bool CanUseRandomIVs () const
 returns whether the object can use random IVs (in addition to ones returned by GetNextIV)
bool CanUsePredictableIVs () const
 returns whether the object can use random but possibly predictable IVs (in addition to ones returned by GetNextIV)
bool CanUseStructuredIVs () const
 returns whether the object can use structured IVs, for example a counter (in addition to ones returned by GetNextIV)
virtual unsigned int IVSize () const
 Returns length of the IV accepted by this object.
unsigned int DefaultIVLength () const
 returns default length of IVs accepted by this object
virtual unsigned int MinIVLength () const
 returns minimal length of IVs accepted by this object
virtual unsigned int MaxIVLength () const
 returns maximal length of IVs accepted by this object
virtual void Resynchronize (const byte *iv, int ivLength=-1)
 resynchronize with an IV. ivLength=-1 means use IVSize()
virtual void GetNextIV (RandomNumberGenerator &rng, byte *iv)
 Gets a secure IV for the next message.
StreamTransformationRef ()
 Provides a reference to this object.
virtual unsigned int MandatoryBlockSize () const
 Provides the mandatory block size of the cipher.
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this cipher.
virtual unsigned int GetOptimalBlockSizeUsed () const
 Provides the number of bytes used in the current block when processing at optimal block size.
virtual unsigned int OptimalDataAlignment () const
 Provides input and output data alignment for optimal performance.
virtual void ProcessData (byte *outString, const byte *inString, size_t length)=0
 Encrypt or decrypt an array of bytes.
virtual void ProcessLastBlock (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt the last block of data.
virtual unsigned int MinLastBlockSize () const
 returns the minimum size of the last block, 0 indicating the last block is not special
void ProcessString (byte *inoutString, size_t length)
 Encrypt or decrypt a string of bytes.
void ProcessString (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt a string of bytes.
byte ProcessByte (byte input)
 Encrypt or decrypt a byte.
virtual bool IsRandomAccess () const =0
 Determines whether the cipher supports random access.
virtual void Seek (lword pos)
 Seek to an absolute position.
virtual bool IsSelfInverting () const =0
 Determines whether the cipher is self-inverting.
virtual bool IsForwardTransformation () const =0
 Determines if the cipher is being operated in its forward direction.
virtual std::string AlgorithmName () const
 Provides the name of this algorithm.
virtual ClonableClone () const
 Copies this object.

Detailed Description

Interface for one direction (encryption or decryption) of a stream cipher or cipher mode.

Definition at line 1020 of file cryptlib.h.


Member Enumeration Documentation

Provides IV requirements as an enumerated value.

Enumerator:
UNIQUE_IV 

The IV must be unique.

RANDOM_IV 

The IV must be random.

UNPREDICTABLE_RANDOM_IV 

The IV must be unpredictable.

INTERNALLY_GENERATED_IV 

The IV is set by the object.

NOT_RESYNCHRONIZABLE 

The object does not use an IV.

Definition at line 555 of file cryptlib.h.


Member Function Documentation

virtual size_t SimpleKeyingInterface::GetValidKeyLength ( size_t  n  )  const [pure virtual, inherited]
virtual bool SimpleKeyingInterface::IsValidKeyLength ( size_t  keylength  )  const [inline, virtual, inherited]

Returns whether keylength is a valid key length.

Internally the function calls GetValidKeyLength()

Reimplemented in CCM_Base, EAX_Base, GCM_Base, and CipherModeBase.

Definition at line 515 of file cryptlib.h.

void SimpleKeyingInterface::SetKey ( const byte *  key,
size_t  length,
const NameValuePairs params = g_nullNameValuePairs 
) [virtual, inherited]

Sets or reset the key of this object.

Parameters:
key the key to use when keying the object
length the size of the key, in bytes
params additional initialization parameters that cannot be passed directly through the constructor

Reimplemented in AuthenticatedSymmetricCipherBase, and ECB_OneWay.

Definition at line 100 of file cryptlib.cpp.

Referenced by HKDF< T >::DeriveKey(), SimpleKeyingInterface::SetKeyWithIV(), SimpleKeyingInterface::SetKeyWithRounds(), VMAC_Base::UncheckedSetKey(), and CMAC_Base::UncheckedSetKey().

void SimpleKeyingInterface::SetKeyWithRounds ( const byte *  key,
size_t  length,
int  rounds 
) [inherited]

Sets or reset the key of this object.

Parameters:
key the key to use when keying the object
length the size of the key, in bytes
rounds the number of rounds to apply the transformation function, if applicable

SetKeyWithRounds calls SetKey with an NameValuePairs object that just specifies rounds. rounds is an integer parameter, and -1 means use the default number of rounds.

Definition at line 106 of file cryptlib.cpp.

References MakeParameters(), Rounds(), and SimpleKeyingInterface::SetKey().

void SimpleKeyingInterface::SetKeyWithIV ( const byte *  key,
size_t  length,
const byte *  iv,
size_t  ivLength 
) [inherited]

Sets or reset the key of this object.

Parameters:
key the key to use when keying the object
length the size of the key, in bytes
iv the intiialization vector to use when keying the object
ivLength the size of the iv, in bytes

SetKeyWithIV calls SetKey with an NameValuePairs object that just specifies iv. iv is a byte buffer with size ivLength.

Definition at line 111 of file cryptlib.cpp.

References IV(), MakeParameters(), and SimpleKeyingInterface::SetKey().

void SimpleKeyingInterface::SetKeyWithIV ( const byte *  key,
size_t  length,
const byte *  iv 
) [inline, inherited]

Sets or reset the key of this object.

Parameters:
key the key to use when keying the object
length the size of the key, in bytes
iv the intiialization vector to use when keying the object

SetKeyWithIV calls SetKey with an NameValuePairs object that just specifies iv. iv is a byte buffer, and it must have a size IVSize.

Definition at line 551 of file cryptlib.h.

References SimpleKeyingInterface::SetKeyWithIV().

Referenced by SimpleKeyingInterface::SetKeyWithIV().

bool SimpleKeyingInterface::IsResynchronizable (  )  const [inline, inherited]

returns whether the object can be resynchronized (i.e. supports initialization vectors)

If this function returns true, and no IV is passed to SetKey() and CanUseStructuredIVs()==true, an IV of all 0's will be assumed.

Definition at line 573 of file cryptlib.h.

Referenced by BlockOrientedCipherModeBase::UncheckedSetKey().

virtual unsigned int SimpleKeyingInterface::IVSize (  )  const [inline, virtual, inherited]
void SimpleKeyingInterface::GetNextIV ( RandomNumberGenerator rng,
byte *  iv 
) [virtual, inherited]

Gets a secure IV for the next message.

Parameters:
rng a RandomNumberGenerator to produce keying material
iv a block of bytes to receive the IV

This method should be called after you finish encrypting one message and are ready to start the next one. After calling it, you must call SetKey() or Resynchronize() before using this object again.

key must be at least IVSize() in length.

Note:
This method is not implemented on decryption objects.

Reimplemented in VMAC_Base.

Definition at line 176 of file cryptlib.cpp.

References RandomNumberGenerator::GenerateBlock(), and SimpleKeyingInterface::IVSize().

StreamTransformation& StreamTransformation::Ref (  )  [inline, inherited]

Provides a reference to this object.

Returns:
A reference to this object

Useful for passing a temporary object to a function that takes a non-const reference

Definition at line 758 of file cryptlib.h.

virtual unsigned int StreamTransformation::MandatoryBlockSize (  )  const [inline, virtual, inherited]

Provides the mandatory block size of the cipher.

Returns:
The block size of the cipher if input must be processed in blocks, 1 otherwise

Reimplemented in BlockOrientedCipherModeBase.

Definition at line 762 of file cryptlib.h.

Referenced by StreamTransformation::ProcessLastBlock().

virtual unsigned int StreamTransformation::OptimalBlockSize (  )  const [inline, virtual, inherited]

Provides the input block size most efficient for this cipher.

Returns:
The input block size that is most efficient for the cipher

The base class implemnetation returns MandatoryBlockSize().

Note:
Optimal input length is n * OptimalBlockSize() - GetOptimalBlockSizeUsed() for any n > 0.

Reimplemented in ECB_OneWay.

Definition at line 769 of file cryptlib.h.

virtual unsigned int StreamTransformation::GetOptimalBlockSizeUsed (  )  const [inline, virtual, inherited]

Provides the number of bytes used in the current block when processing at optimal block size.

Returns:
the number of bytes used in the current block when processing at the optimal block size

Definition at line 773 of file cryptlib.h.

unsigned int StreamTransformation::OptimalDataAlignment (  )  const [virtual, inherited]

Provides input and output data alignment for optimal performance.

Returns:
the input data alignment that provides optimal performance

Reimplemented in CCM_Base, EAX_Base, GCM_Base, and CipherModeBase.

Definition at line 237 of file cryptlib.cpp.

virtual void StreamTransformation::ProcessData ( byte *  outString,
const byte *  inString,
size_t  length 
) [pure virtual, inherited]

Encrypt or decrypt an array of bytes.

Parameters:
outString the output byte buffer
inString the input byte buffer
length the size of the input and output byte buffers, in bytes

Either inString == outString, or they must not overlap.

Implemented in Weak1::ARC4_Base, AuthenticatedSymmetricCipherBase, PublicBlumBlumShub, ECB_OneWay, CBC_Encryption, and CBC_Decryption.

Referenced by AuthenticatedSymmetricCipherBase::ProcessData(), and StreamTransformation::ProcessLastBlock().

void StreamTransformation::ProcessLastBlock ( byte *  outString,
const byte *  inString,
size_t  length 
) [virtual, inherited]

Encrypt or decrypt the last block of data.

Parameters:
outString the output byte buffer
inString the input byte buffer
length the size of the input and output byte buffers, in bytes ProcessLastBlock is used when the last block of data is special. Currently the only use of this function is CBC-CTS mode.

Reimplemented in CBC_CTS_Encryption, and CBC_CTS_Decryption.

Definition at line 247 of file cryptlib.cpp.

References Algorithm::AlgorithmName(), StreamTransformation::MandatoryBlockSize(), StreamTransformation::MinLastBlockSize(), and StreamTransformation::ProcessData().

void StreamTransformation::ProcessString ( byte *  inoutString,
size_t  length 
) [inline, inherited]

Encrypt or decrypt a string of bytes.

Parameters:
inoutString the string to process
length the size of the inoutString, in bytes

Internally, the base class implementation calls ProcessData().

Definition at line 801 of file cryptlib.h.

Referenced by AuthenticatedSymmetricCipher::DecryptAndVerify(), and AuthenticatedSymmetricCipher::EncryptAndAuthenticate().

void StreamTransformation::ProcessString ( byte *  outString,
const byte *  inString,
size_t  length 
) [inline, inherited]

Encrypt or decrypt a string of bytes.

Parameters:
outString the output string to process
inString the input string to process
length the size of the input and output strings, in bytes

Internally, the base class implementation calls ProcessData().

Definition at line 809 of file cryptlib.h.

byte StreamTransformation::ProcessByte ( byte  input  )  [inline, inherited]

Encrypt or decrypt a byte.

Parameters:
input the input byte to process

Internally, the base class implementation calls ProcessData() with a size of 1.

Definition at line 815 of file cryptlib.h.

virtual bool StreamTransformation::IsRandomAccess (  )  const [pure virtual, inherited]

Determines whether the cipher supports random access.

Returns:
true if the cipher supports random access, false otherwise

Implemented in Weak1::ARC4_Base, AuthenticatedSymmetricCipherBase, BlumBlumShub, and BlockOrientedCipherModeBase.

virtual void StreamTransformation::Seek ( lword  pos  )  [inline, virtual, inherited]

Seek to an absolute position.

Parameters:
pos position to seek
Exceptions:
NotImplemented 

The base class implementation throws NotImplemented. The function asserts IsRandomAccess() in debug builds.

Reimplemented in BlumBlumShub.

Definition at line 827 of file cryptlib.h.

virtual bool StreamTransformation::IsSelfInverting (  )  const [pure virtual, inherited]

Determines whether the cipher is self-inverting.

Returns:
true if the cipher is self-inverting, false otherwise

IsSelfInverting determines whether this transformation is self-inverting (e.g. xor with a keystream).

Implemented in Weak1::ARC4_Base, AuthenticatedSymmetricCipherBase, PublicBlumBlumShub, and BlockOrientedCipherModeBase.

Referenced by AuthenticatedDecryptionFilter::AuthenticatedDecryptionFilter().

virtual bool StreamTransformation::IsForwardTransformation (  )  const [pure virtual, inherited]
virtual std::string Algorithm::AlgorithmName (  )  const [inline, virtual, inherited]

Provides the name of this algorithm.

Returns:
the standard algorithm name

The standard algorithm name can be a name like AES or AES/GCM. Some algorithms do not have standard names yet. For example, there is no standard algorithm name for Shoup's ECIES.

Note:
AlgorithmName is not universally implemented yet

Reimplemented in Adler32, CCM_Base, CRC32, ClassNullRNG, AuthenticatedSymmetricCipher, DH_Domain< GROUP_PARAMETERS, COFACTOR_OPTION >, EAX_Base, StreamTransformationFilter, HashFilter, HashVerificationFilter, AuthenticatedDecryptionFilter, SignerFilter, SignatureVerificationFilter, GCM_Base, HMAC< T >, RDRAND, RDSEED, SHA3, BitBucket, and VMAC_Base.

Definition at line 488 of file cryptlib.h.

Referenced by BufferedTransformation::ChannelCreatePutSpace(), BufferedTransformation::ChannelFlush(), BufferedTransformation::ChannelMessageSeriesEnd(), BufferedTransformation::ChannelPut2(), TF_DecryptorBase::Decrypt(), TF_EncryptorBase::Encrypt(), StreamTransformation::ProcessLastBlock(), and PK_DefaultDecryptionFilter::Put2().

virtual Clonable* Clonable::Clone (  )  const [inline, virtual, inherited]

Copies this object.

Returns:
a copy of this object
Exceptions:
NotImplemented 
Note:
this is not implemented by most classes
See also:
NotCopyable

Definition at line 464 of file cryptlib.h.


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

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