Crypto++  5.6.3
Free C++ class library of cryptographic schemes
Classes | Public Member Functions | List of all members
AuthenticatedSymmetricCipher Class Referenceabstract

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

+ Inheritance diagram for AuthenticatedSymmetricCipher:

Classes

class  BadState
 Exception thrown when the object is in the wrong state for the operation. More...
 

Public Member Functions

virtual lword MaxHeaderLength () const =0
 Provides the maximum length of AAD that can be input. More...
 
virtual lword MaxMessageLength () const =0
 Provides the maximum length of encrypted data. More...
 
virtual lword MaxFooterLength () const
 Provides the the maximum length of AAD. More...
 
virtual bool NeedsPrespecifiedDataLengths () const
 Determines if data lengths must be specified prior to inputting data. More...
 
void SpecifyDataLengths (lword headerLength, lword messageLength, lword footerLength=0)
 Prespecifies the data lengths. More...
 
virtual void EncryptAndAuthenticate (byte *ciphertext, byte *mac, size_t macSize, const byte *iv, int ivLength, const byte *header, size_t headerLength, const byte *message, size_t messageLength)
 Encrypts and calculates a MAC in one call. More...
 
virtual bool DecryptAndVerify (byte *message, const byte *mac, size_t macLength, const byte *iv, int ivLength, const byte *header, size_t headerLength, const byte *ciphertext, size_t ciphertextLength)
 Decrypts and verifies a MAC in one call. More...
 
virtual std::string AlgorithmName () const =0
 Provides the name of this algorithm. More...
 
- Public Member Functions inherited from SimpleKeyingInterface
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. More...
 
virtual void SetKey (const byte *key, size_t length, const NameValuePairs &params=g_nullNameValuePairs)
 Sets or reset the key of this object. More...
 
void SetKeyWithRounds (const byte *key, size_t length, int rounds)
 Sets or reset the key of this object. More...
 
void SetKeyWithIV (const byte *key, size_t length, const byte *iv, size_t ivLength)
 Sets or reset the key of this object. More...
 
void SetKeyWithIV (const byte *key, size_t length, const byte *iv)
 Sets or reset the key of this object. More...
 
virtual IV_Requirement IVRequirement () const =0
 Minimal requirement for secure IVs. More...
 
bool IsResynchronizable () const
 Determines if the object can be resynchronized. More...
 
bool CanUseRandomIVs () const
 Determines if the object can use random IVs. More...
 
bool CanUsePredictableIVs () const
 Determines if the object can use random but possibly predictable IVs. More...
 
bool CanUseStructuredIVs () const
 Determines if the object can use structured IVs returns whether the object can use structured IVs, for example a counter (in addition to ones returned by GetNextIV), false otherwise.
 
virtual unsigned int IVSize () const
 Returns length of the IV accepted by this object. More...
 
unsigned int DefaultIVLength () const
 Provides the default size of an IV. More...
 
virtual unsigned int MinIVLength () const
 Provides the minimum size of an IV. More...
 
virtual unsigned int MaxIVLength () const
 Provides the maximum size of an IV. More...
 
virtual void Resynchronize (const byte *iv, int ivLength=-1)
 Resynchronize with an IV. More...
 
virtual void GetNextIV (RandomNumberGenerator &rng, byte *iv)
 Retrieves a secure IV for the next message. More...
 
- Public Member Functions inherited from HashTransformation
HashTransformationRef ()
 Provides a reference to this object. More...
 
virtual void Update (const byte *input, size_t length)=0
 Updates a hash with additional input. More...
 
virtual byte * CreateUpdateSpace (size_t &size)
 Request space which can be written into by the caller. More...
 
virtual void Final (byte *digest)
 Computes the hash of the current message. More...
 
virtual void Restart ()
 Restart the hash. More...
 
virtual unsigned int DigestSize () const =0
 Provides the digest size of the hash. More...
 
unsigned int TagSize () const
 Provides the tag size of the hash. More...
 
virtual unsigned int BlockSize () const
 Provides the block size of the compression function. More...
 
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this hash. More...
 
virtual unsigned int OptimalDataAlignment () const
 Provides input and output data alignment for optimal performance. More...
 
virtual void CalculateDigest (byte *digest, const byte *input, size_t length)
 Updates the hash with additional input and computes the hash of the current message. More...
 
virtual bool Verify (const byte *digest)
 Verifies the hash of the current message. More...
 
virtual bool VerifyDigest (const byte *digest, const byte *input, size_t length)
 Updates the hash with additional input and verifies the hash of the current message. More...
 
virtual void TruncatedFinal (byte *digest, size_t digestSize)=0
 Computes the hash of the current message. More...
 
virtual void CalculateTruncatedDigest (byte *digest, size_t digestSize, const byte *input, size_t length)
 Updates the hash with additional input and computes the hash of the current message. More...
 
virtual bool TruncatedVerify (const byte *digest, size_t digestLength)
 Verifies the hash of the current message. More...
 
virtual bool VerifyTruncatedDigest (const byte *digest, size_t digestLength, const byte *input, size_t length)
 Updates the hash with additional input and verifies the hash of the current message. More...
 
- Public Member Functions inherited from Algorithm
 Algorithm (bool checkSelfTestStatus=true)
 Interface for all crypto algorithms. More...
 
- Public Member Functions inherited from Clonable
virtual ClonableClone () const
 Copies this object. More...
 
- Public Member Functions inherited from StreamTransformation
StreamTransformationRef ()
 Provides a reference to this object. More...
 
virtual unsigned int MandatoryBlockSize () const
 Provides the mandatory block size of the cipher. More...
 
virtual unsigned int OptimalBlockSize () const
 Provides the input block size most efficient for this cipher. More...
 
virtual unsigned int GetOptimalBlockSizeUsed () const
 Provides the number of bytes used in the current block when processing at optimal block size. More...
 
virtual unsigned int OptimalDataAlignment () const
 Provides input and output data alignment for optimal performance. More...
 
virtual void ProcessData (byte *outString, const byte *inString, size_t length)=0
 Encrypt or decrypt an array of bytes. More...
 
virtual void ProcessLastBlock (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt the last block of data. More...
 
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. More...
 
void ProcessString (byte *outString, const byte *inString, size_t length)
 Encrypt or decrypt a string of bytes. More...
 
byte ProcessByte (byte input)
 Encrypt or decrypt a byte. More...
 
virtual bool IsRandomAccess () const =0
 Determines whether the cipher supports random access. More...
 
virtual void Seek (lword pos)
 Seek to an absolute position. More...
 
virtual bool IsSelfInverting () const =0
 Determines whether the cipher is self-inverting. More...
 
virtual bool IsForwardTransformation () const =0
 Determines if the cipher is being operated in its forward direction. More...
 

Additional Inherited Members

- Public Types inherited from SimpleKeyingInterface
enum  IV_Requirement {
  UNIQUE_IV = 0, RANDOM_IV, UNPREDICTABLE_RANDOM_IV, INTERNALLY_GENERATED_IV,
  NOT_RESYNCHRONIZABLE
}
 Secure IVs requirements as enumerated values. More...
 

Detailed Description

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

The StreamTransformation part of this interface is used to encrypt/decrypt the data, and the MessageAuthenticationCode part of this interface is used to input additional authenticated data (AAD, which is MAC'ed but not encrypted), and to generate/verify the MAC.

Definition at line 1117 of file cryptlib.h.

Member Function Documentation

virtual lword AuthenticatedSymmetricCipher::MaxHeaderLength ( ) const
pure virtual

Provides the maximum length of AAD that can be input.

Returns
the maximum length of AAD that can be input before the encrypted data

Implemented in GCM_Base, CCM_Base, and EAX_Base.

virtual lword AuthenticatedSymmetricCipher::MaxMessageLength ( ) const
pure virtual

Provides the maximum length of encrypted data.

Returns
the maximum length of encrypted data

Implemented in GCM_Base, CCM_Base, and EAX_Base.

virtual lword AuthenticatedSymmetricCipher::MaxFooterLength ( ) const
inlinevirtual

Provides the the maximum length of AAD.

Returns
the maximum length of AAD that can be input after the encrypted data

Definition at line 1142 of file cryptlib.h.

virtual bool AuthenticatedSymmetricCipher::NeedsPrespecifiedDataLengths ( ) const
inlinevirtual

Determines if data lengths must be specified prior to inputting data.

Returns
true if the data lengths are required before inputting data, false otherwise

if this function returns true, SpecifyDataLengths() must be called before attempting to input data. This is the case for some schemes, such as CCM.

See also
SpecifyDataLengths()

Reimplemented in CCM_Base.

Definition at line 1148 of file cryptlib.h.

void AuthenticatedSymmetricCipher::SpecifyDataLengths ( lword  headerLength,
lword  messageLength,
lword  footerLength = 0 
)

Prespecifies the data lengths.

this function only needs to be called if NeedsPrespecifiedDataLengths() returns true

See also
NeedsPrespecifiedDataLengths()

Definition at line 257 of file cryptlib.cpp.

void AuthenticatedSymmetricCipher::EncryptAndAuthenticate ( byte *  ciphertext,
byte *  mac,
size_t  macSize,
const byte *  iv,
int  ivLength,
const byte *  header,
size_t  headerLength,
const byte *  message,
size_t  messageLength 
)
virtual

Encrypts and calculates a MAC in one call.

Returns
true if the authenticated encryption succeeded, false otherwise

EncryptAndAuthenticate() encrypts and generates the MAC in one call. The function will truncate MAC if macSize < TagSize().

Definition at line 271 of file cryptlib.cpp.

bool AuthenticatedSymmetricCipher::DecryptAndVerify ( byte *  message,
const byte *  mac,
size_t  macLength,
const byte *  iv,
int  ivLength,
const byte *  header,
size_t  headerLength,
const byte *  ciphertext,
size_t  ciphertextLength 
)
virtual

Decrypts and verifies a MAC in one call.

Returns
true if the MAC is valid and the decoding succeeded, false otherwise

DecryptAndVerify() decrypts and verifies the MAC in one call. The function returns true iff MAC is valid. DecryptAndVerify() will assume MAC is truncated if macLength < TagSize().

Definition at line 280 of file cryptlib.cpp.

virtual std::string AuthenticatedSymmetricCipher::AlgorithmName ( ) const
pure virtual

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.

Reimplemented from Algorithm.

Implemented in GCM_Base, CCM_Base, and EAX_Base.


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