Team Fortress 2 Source Code as on 22/4/2020
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// seckey.h - written and placed in the public domain by Wei Dai
//! \file
//! \brief Classes and functions for implementing secret key algorithms.
#ifndef CRYPTOPP_SECKEY_H
#define CRYPTOPP_SECKEY_H
#include "config.h"
#if CRYPTOPP_MSC_VERSION
# pragma warning(push)
# pragma warning(disable: 4189)
#endif
#include "cryptlib.h"
#include "misc.h"
#include "simple.h"
NAMESPACE_BEGIN(CryptoPP)
//! \brief Inverts the cipher's direction
//! \param dir the cipher's direction
//! \returns DECRYPTION if dir is ENCRYPTION, DECRYPTION otherwise
inline CipherDir ReverseCipherDir(CipherDir dir)
{
return (dir == ENCRYPTION) ? DECRYPTION : ENCRYPTION;
}
//! \class FixedBlockSize
//! \brief Inherited by block ciphers with fixed block size
//! \tparam N the blocksize of the cipher
template <unsigned int N>
class FixedBlockSize
{
public:
//! \brief The block size of the cipher provided as a constant.
CRYPTOPP_CONSTANT(BLOCKSIZE = N)
};
// ************** rounds ***************
//! \class FixedRounds
//! \brief Inherited by ciphers with fixed number of rounds
//! \tparam R the number of rounds used by the cipher
template <unsigned int R>
class FixedRounds
{
public:
//! \brief The number of rounds for the cipher provided as a constant.
CRYPTOPP_CONSTANT(ROUNDS = R)
};
//! \class VariableRounds
//! \brief Inherited by ciphers with variable number of rounds
//! \tparam D Default number of rounds
//! \tparam N Minimum number of rounds
//! \tparam D Maximum number of rounds
template <unsigned int D, unsigned int N=1, unsigned int M=INT_MAX> // use INT_MAX here because enums are treated as signed ints
class VariableRounds
{
public:
//! \brief The default number of rounds for the cipher provided as a constant.
CRYPTOPP_CONSTANT(DEFAULT_ROUNDS = D)
//! \brief The minimum number of rounds for the cipher provided as a constant.
CRYPTOPP_CONSTANT(MIN_ROUNDS = N)
//! \brief The maximum number of rounds for the cipher provided as a constant.
CRYPTOPP_CONSTANT(MAX_ROUNDS = M)
//! \brief The default number of rounds for the cipher based on key length
//! provided by a static function.
//! \param keylength the size of the key, in bytes
//! \details keylength is unused in the default implementation.
static unsigned int StaticGetDefaultRounds(size_t keylength)
{CRYPTOPP_UNUSED(keylength); return DEFAULT_ROUNDS;}
protected:
//! \brief Validates the number of rounds for a cipher.
//! \param rounds the canddiate number of rounds
//! \param alg an Algorithm object used if the number of rounds are invalid
//! \throws InvalidRounds if the number of rounds are invalid
inline void ThrowIfInvalidRounds(int rounds, const Algorithm *alg)
{
#if (M==INT_MAX) // Coverity and result_independent_of_operands
if (rounds < MIN_ROUNDS)
throw InvalidRounds(alg ? alg->AlgorithmName() : "VariableRounds", rounds);
#else
if (rounds < MIN_ROUNDS || rounds > MAX_ROUNDS)
throw InvalidRounds(alg ? alg->AlgorithmName() : "VariableRounds", rounds);
#endif
}
//! \brief Validates the number of rounds for a cipher
//! \param param the canddiate number of rounds
//! \param alg an Algorithm object used if the number of rounds are invalid
//! \returns the number of rounds for the cipher
//! \throws InvalidRounds if the number of rounds are invalid
inline unsigned int GetRoundsAndThrowIfInvalid(const NameValuePairs &param, const Algorithm *alg)
{
int rounds = param.GetIntValueWithDefault("Rounds", DEFAULT_ROUNDS);
ThrowIfInvalidRounds(rounds, alg);
return (unsigned int)rounds;
}
};
// ************** key length ***************
//! \class FixedKeyLength
//! \brief Inherited by keyed algorithms with fixed key length
//! \tparam N Default key length, in bytes
//! \tparam IV_REQ The IV requirements. See IV_Requirement in cryptlib.h for allowed values
//! \tparam IV_L Default IV length, in bytes
template <unsigned int N, unsigned int IV_REQ = SimpleKeyingInterface::NOT_RESYNCHRONIZABLE, unsigned int IV_L = 0>
class FixedKeyLength
{
public:
//! \brief The default key length used by the cipher provided as a constant
//! \details KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(KEYLENGTH=N)
//! \brief The minimum key length used by the cipher provided as a constant
//! \details MIN_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(MIN_KEYLENGTH=N)
//! \brief The maximum key length used by the cipher provided as a constant
//! \details MAX_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(MAX_KEYLENGTH=N)
//! \brief The default key length used by the cipher provided as a constant
//! \details DEFAULT_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH=N)
//! \brief The default IV requirements for the cipher provided as a constant
//! \details The default value is NOT_RESYNCHRONIZABLE. See IV_Requirement
//! in cryptlib.h for allowed values.
CRYPTOPP_CONSTANT(IV_REQUIREMENT = IV_REQ)
//! \brief The default IV length used by the cipher provided as a constant
//! \details IV_LENGTH is provided in bytes, not bits. The default implementation uses 0.
CRYPTOPP_CONSTANT(IV_LENGTH = IV_L)
//! \brief The default key length for the cipher provided by a static function.
//! \param keylength the size of the key, in bytes
//! \details The default implementation returns KEYLENGTH. keylength is unused
//! in the default implementation.
static size_t CRYPTOPP_API StaticGetValidKeyLength(size_t keylength)
{CRYPTOPP_UNUSED(keylength); return KEYLENGTH;}
};
//! \class VariableKeyLength
//! \brief Inherited by keyed algorithms with variable key length
//! \tparam D Default key length, in bytes
//! \tparam N Minimum key length, in bytes
//! \tparam M Maximum key length, in bytes
//! \tparam M Default key length multiple, in bytes. The default multiple is 1.
//! \tparam IV_REQ The IV requirements. See IV_Requirement in cryptlib.h for allowed values
//! \tparam IV_L Default IV length, in bytes. The default length is 0.
template <unsigned int D, unsigned int N, unsigned int M, unsigned int Q = 1, unsigned int IV_REQ = SimpleKeyingInterface::NOT_RESYNCHRONIZABLE, unsigned int IV_L = 0>
class VariableKeyLength
{
// Make these private to avoid Doxygen documenting them in all derived classes
CRYPTOPP_COMPILE_ASSERT(Q > 0);
CRYPTOPP_COMPILE_ASSERT(N % Q == 0);
CRYPTOPP_COMPILE_ASSERT(M % Q == 0);
CRYPTOPP_COMPILE_ASSERT(N < M);
CRYPTOPP_COMPILE_ASSERT(D >= N);
CRYPTOPP_COMPILE_ASSERT(M >= D);
public:
//! \brief The minimum key length used by the cipher provided as a constant
//! \details MIN_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(MIN_KEYLENGTH=N)
//! \brief The maximum key length used by the cipher provided as a constant
//! \details MAX_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(MAX_KEYLENGTH=M)
//! \brief The default key length used by the cipher provided as a constant
//! \details DEFAULT_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH=D)
//! \brief The key length multiple used by the cipher provided as a constant
//! \details MAX_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(KEYLENGTH_MULTIPLE=Q)
//! \brief The default IV requirements for the cipher provided as a constant
//! \details The default value is NOT_RESYNCHRONIZABLE. See IV_Requirement
//! in cryptlib.h for allowed values.
CRYPTOPP_CONSTANT(IV_REQUIREMENT=IV_REQ)
//! \brief The default initialization vector length for the cipher provided as a constant
//! \details IV_LENGTH is provided in bytes, not bits. The default implementation uses 0.
CRYPTOPP_CONSTANT(IV_LENGTH=IV_L)
//! \brief Provides a valid key length for the cipher provided by a static function.
//! \param keylength the size of the key, in bytes
//! \details If keylength is less than MIN_KEYLENGTH, then the function returns
//! MIN_KEYLENGTH. If keylength is greater than MAX_KEYLENGTH, then the function
//! returns MAX_KEYLENGTH. If keylength is a multiple of KEYLENGTH_MULTIPLE,
//! then keylength is returned. Otherwise, the function returns keylength rounded
//! \a down to the next smaller multiple of KEYLENGTH_MULTIPLE.
//! \details keylength is provided in bytes, not bits.
static size_t CRYPTOPP_API StaticGetValidKeyLength(size_t keylength)
{
#if MIN_KEYLENGTH > 0
if (keylength < (size_t)MIN_KEYLENGTH)
return MIN_KEYLENGTH;
else
#endif
if (keylength > (size_t)MAX_KEYLENGTH)
return (size_t)MAX_KEYLENGTH;
else
{
keylength += KEYLENGTH_MULTIPLE-1;
return keylength - keylength%KEYLENGTH_MULTIPLE;
}
}
};
//! \class SameKeyLengthAs
//! \brief Provides key lengths based on another class's key length
//! \tparam T another FixedKeyLength or VariableKeyLength class
//! \tparam IV_REQ The IV requirements. See IV_Requirement in cryptlib.h for allowed values
//! \tparam IV_L Default IV length, in bytes
template <class T, unsigned int IV_REQ = SimpleKeyingInterface::NOT_RESYNCHRONIZABLE, unsigned int IV_L = 0>
class SameKeyLengthAs
{
public:
//! \brief The minimum key length used by the cipher provided as a constant
//! \details MIN_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(MIN_KEYLENGTH=T::MIN_KEYLENGTH)
//! \brief The maximum key length used by the cipher provided as a constant
//! \details MIN_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(MAX_KEYLENGTH=T::MAX_KEYLENGTH)
//! \brief The default key length used by the cipher provided as a constant
//! \details MIN_KEYLENGTH is provided in bytes, not bits
CRYPTOPP_CONSTANT(DEFAULT_KEYLENGTH=T::DEFAULT_KEYLENGTH)
//! \brief The default IV requirements for the cipher provided as a constant
//! \details The default value is NOT_RESYNCHRONIZABLE. See IV_Requirement
//! in cryptlib.h for allowed values.
CRYPTOPP_CONSTANT(IV_REQUIREMENT=IV_REQ)
//! \brief The default initialization vector length for the cipher provided as a constant
//! \details IV_LENGTH is provided in bytes, not bits. The default implementation uses 0.
CRYPTOPP_CONSTANT(IV_LENGTH=IV_L)
//! \brief Provides a valid key length for the cipher provided by a static function.
//! \param keylength the size of the key, in bytes
//! \details If keylength is less than MIN_KEYLENGTH, then the function returns
//! MIN_KEYLENGTH. If keylength is greater than MAX_KEYLENGTH, then the function
//! returns MAX_KEYLENGTH. If keylength is a multiple of KEYLENGTH_MULTIPLE,
//! then keylength is returned. Otherwise, the function returns keylength rounded
//! \a down to the next smaller multiple of KEYLENGTH_MULTIPLE.
//! \details keylength is provided in bytes, not bits.
static size_t CRYPTOPP_API StaticGetValidKeyLength(size_t keylength)
{return T::StaticGetValidKeyLength(keylength);}
};
// ************** implementation helper for SimpleKeyed ***************
//! \class SimpleKeyingInterfaceImpl
//! \brief Provides class member functions to access SimpleKeyingInterface constants
//! \tparam BASE a SimpleKeyingInterface derived class
//! \tparam INFO a SimpleKeyingInterface derived class
template <class BASE, class INFO = BASE>
class CRYPTOPP_NO_VTABLE SimpleKeyingInterfaceImpl : public BASE
{
public:
//! \brief The minimum key length used by the cipher
size_t MinKeyLength() const
{return INFO::MIN_KEYLENGTH;}
//! \brief The maximum key length used by the cipher
size_t MaxKeyLength() const
{return (size_t)INFO::MAX_KEYLENGTH;}
//! \brief The default key length used by the cipher
size_t DefaultKeyLength() const
{return INFO::DEFAULT_KEYLENGTH;}
//! \brief Provides a valid key length for the cipher
//! \param keylength the size of the key, in bytes
//! \details keylength is provided in bytes, not bits. If keylength is less than MIN_KEYLENGTH,
//! then the function returns MIN_KEYLENGTH. If keylength is greater than MAX_KEYLENGTH,
//! then the function returns MAX_KEYLENGTH. if If keylength is a multiple of KEYLENGTH_MULTIPLE,
//! then keylength is returned. Otherwise, the function returns a \a lower multiple of
//! KEYLENGTH_MULTIPLE.
size_t GetValidKeyLength(size_t keylength) const {return INFO::StaticGetValidKeyLength(keylength);}
//! \brief The default IV requirements for the cipher
//! \details The default value is NOT_RESYNCHRONIZABLE. See IV_Requirement
//! in cryptlib.h for allowed values.
SimpleKeyingInterface::IV_Requirement IVRequirement() const
{return (SimpleKeyingInterface::IV_Requirement)INFO::IV_REQUIREMENT;}
//! \brief The default initialization vector length for the cipher
//! \details IVSize is provided in bytes, not bits. The default implementation uses IV_LENGTH, which is 0.
unsigned int IVSize() const
{return INFO::IV_LENGTH;}
};
//! \class BlockCipherImpl
//! \brief Provides class member functions to access BlockCipher constants
//! \tparam INFO a SimpleKeyingInterface derived class
//! \tparam BASE a SimpleKeyingInterface derived class
template <class INFO, class BASE = BlockCipher>
class CRYPTOPP_NO_VTABLE BlockCipherImpl : public AlgorithmImpl<SimpleKeyingInterfaceImpl<TwoBases<BASE, INFO> > >
{
public:
//! Provides the block size of the cipher
//! \returns the block size of the cipher, in bytes
unsigned int BlockSize() const {return this->BLOCKSIZE;}
};
//! \class BlockCipherFinal
//! \brief Provides class member functions to key a block cipher
//! \tparam DIR a CipherDir
//! \tparam BASE a BlockCipherImpl derived class
template <CipherDir DIR, class BASE>
class BlockCipherFinal : public ClonableImpl<BlockCipherFinal<DIR, BASE>, BASE>
{
public:
//! \brief Construct a default BlockCipherFinal
//! \details The cipher is not keyed.
BlockCipherFinal() {}
//! \brief Construct a BlockCipherFinal
//! \param key a byte array used to key the cipher
//! \details key must be at least DEFAULT_KEYLENGTH in length. Internally, the function calls
//! SimpleKeyingInterface::SetKey.
BlockCipherFinal(const byte *key)
{this->SetKey(key, this->DEFAULT_KEYLENGTH);}
//! \brief Construct a BlockCipherFinal
//! \param key a byte array used to key the cipher
//! \param length the length of the byte array
//! \details key must be at least DEFAULT_KEYLENGTH in length. Internally, the function calls
//! SimpleKeyingInterface::SetKey.
BlockCipherFinal(const byte *key, size_t length)
{this->SetKey(key, length);}
//! \brief Construct a BlockCipherFinal
//! \param key a byte array used to key the cipher
//! \param length the length of the byte array
//! \param rounds the number of rounds
//! \details key must be at least DEFAULT_KEYLENGTH in length. Internally, the function calls
//! SimpleKeyingInterface::SetKeyWithRounds.
BlockCipherFinal(const byte *key, size_t length, unsigned int rounds)
{this->SetKeyWithRounds(key, length, rounds);}
//! \brief Provides the direction of the cipher
//! \returns true if DIR is ENCRYPTION, false otherwise
//! \sa IsForwardTransformation(), IsPermutation(), GetCipherDirection()
bool IsForwardTransformation() const {return DIR == ENCRYPTION;}
};
//! \class MessageAuthenticationCodeImpl
//! \brief Provides class member functions to access MessageAuthenticationCode constants
//! \tparam INFO a SimpleKeyingInterface derived class
//! \tparam BASE a SimpleKeyingInterface derived class
template <class BASE, class INFO = BASE>
class MessageAuthenticationCodeImpl : public AlgorithmImpl<SimpleKeyingInterfaceImpl<BASE, INFO>, INFO>
{
};
//! \class MessageAuthenticationCodeFinal
//! \brief Provides class member functions to key a message authentication code
//! \tparam DIR a CipherDir
//! \tparam BASE a BlockCipherImpl derived class
template <class BASE>
class MessageAuthenticationCodeFinal : public ClonableImpl<MessageAuthenticationCodeFinal<BASE>, MessageAuthenticationCodeImpl<BASE> >
{
public:
//! \brief Construct a default MessageAuthenticationCodeFinal
//! \details The message authentication code is not keyed.
MessageAuthenticationCodeFinal() {}
//! \brief Construct a BlockCipherFinal
//! \param key a byte array used to key the cipher
//! \details key must be at least DEFAULT_KEYLENGTH in length. Internally, the function calls
//! SimpleKeyingInterface::SetKey.
MessageAuthenticationCodeFinal(const byte *key)
{this->SetKey(key, this->DEFAULT_KEYLENGTH);}
//! \brief Construct a BlockCipherFinal
//! \param key a byte array used to key the cipher
//! \param length the length of the byte array
//! \details key must be at least DEFAULT_KEYLENGTH in length. Internally, the function calls
//! SimpleKeyingInterface::SetKey.
MessageAuthenticationCodeFinal(const byte *key, size_t length)
{this->SetKey(key, length);}
};
// ************** documentation ***************
//! \class BlockCipherDocumentation
//! \brief Provides Encryption and Decryption typedefs used by derived classes to
//! implement a block cipher
//! \details These objects usually should not be used directly. See CipherModeDocumentation
//! instead. Each class derived from this one defines two types, Encryption and Decryption,
//! both of which implement the BlockCipher interface.
struct BlockCipherDocumentation
{
//! implements the BlockCipher interface
typedef BlockCipher Encryption;
//! implements the BlockCipher interface
typedef BlockCipher Decryption;
};
//! \class SymmetricCipherDocumentation
//! \brief Provides Encryption and Decryption typedefs used by derived classes to
//! implement a symmetric cipher
//! \details Each class derived from this one defines two types, Encryption and Decryption,
//! both of which implement the SymmetricCipher interface. Two types of classes derive
//! from this class: stream ciphers and block cipher modes. Stream ciphers can be used
//! alone, cipher mode classes need to be used with a block cipher. See CipherModeDocumentation
//! for more for information about using cipher modes and block ciphers.
struct SymmetricCipherDocumentation
{
//! implements the SymmetricCipher interface
typedef SymmetricCipher Encryption;
//! implements the SymmetricCipher interface
typedef SymmetricCipher Decryption;
};
//! \class AuthenticatedSymmetricCipherDocumentation
//! \brief Provides Encryption and Decryption typedefs used by derived classes to
//! implement an authenticated encryption cipher
//! \details Each class derived from this one defines two types, Encryption and Decryption,
//! both of which implement the AuthenticatedSymmetricCipher interface.
struct AuthenticatedSymmetricCipherDocumentation
{
//! implements the AuthenticatedSymmetricCipher interface
typedef AuthenticatedSymmetricCipher Encryption;
//! implements the AuthenticatedSymmetricCipher interface
typedef AuthenticatedSymmetricCipher Decryption;
};
NAMESPACE_END
#if CRYPTOPP_MSC_VERSION
# pragma warning(pop)
#endif
#endif