Botan  1.10.9
Public Types | Public Member Functions | Protected Member Functions | List of all members
Botan::XTEA Class Reference

#include <xtea.h>

Inheritance diagram for Botan::XTEA:
Botan::Block_Cipher_Fixed_Params< 8, 16 > Botan::BlockCipher Botan::SymmetricAlgorithm Botan::Algorithm Botan::XTEA_SIMD

Public Types

enum  
 

Public Member Functions

size_t block_size () const
 
void clear ()
 
BlockCipherclone () const
 
void decrypt (const byte in[], byte out[]) const
 
void decrypt (byte block[]) const
 
void decrypt_n (const byte in[], byte out[], size_t blocks) const
 
void encrypt (const byte in[], byte out[]) const
 
void encrypt (byte block[]) const
 
void encrypt_n (const byte in[], byte out[], size_t blocks) const
 
Key_Length_Specification key_spec () const
 
size_t maximum_keylength () const
 
size_t minimum_keylength () const
 
std::string name () const
 
size_t parallel_bytes () const
 
virtual size_t parallelism () const
 
void set_key (const SymmetricKey &key)
 
void set_key (const byte key[], size_t length)
 
bool valid_keylength (size_t length) const
 
 XTEA ()
 

Protected Member Functions

const SecureVector< u32bit > & get_EK () const
 

Detailed Description

XTEA

Definition at line 18 of file xtea.h.

Member Enumeration Documentation

anonymous enum
inherited

Constructor & Destructor Documentation

Botan::XTEA::XTEA ( )
inline

Definition at line 28 of file xtea.h.

28 : EK(64) {}

Member Function Documentation

size_t Botan::Block_Cipher_Fixed_Params< BS, KMIN, 0 , 1 >::block_size ( ) const
inlinevirtualinherited
Returns
block size of this algorithm

Implements Botan::BlockCipher.

Definition at line 108 of file block_cipher.h.

108 { return BS; }
void Botan::XTEA::clear ( )
inlinevirtual

Zeroize internal state

Implements Botan::Algorithm.

Definition at line 24 of file xtea.h.

References Botan::zeroise().

24 { zeroise(EK); }
void zeroise(MemoryRegion< T > &vec)
Definition: secmem.h:415
BlockCipher* Botan::XTEA::clone ( ) const
inlinevirtual

Get a new object representing the same algorithm as *this

Implements Botan::BlockCipher.

Reimplemented in Botan::XTEA_SIMD.

Definition at line 26 of file xtea.h.

26 { return new XTEA; }
XTEA()
Definition: xtea.h:28
void Botan::BlockCipher::decrypt ( const byte  in[],
byte  out[] 
) const
inlineinherited

Decrypt a block.

Parameters
inThe ciphertext block to be decypted as a byte array. Must be of length block_size().
outThe byte array designated to hold the decrypted block. Must be of length block_size().

Definition at line 57 of file block_cipher.h.

Referenced by Botan::DESX::decrypt_n().

58  { decrypt_n(in, out, 1); }
virtual void decrypt_n(const byte in[], byte out[], size_t blocks) const =0
void Botan::BlockCipher::decrypt ( byte  block[]) const
inlineinherited

Decrypt a block.

Parameters
blockthe ciphertext block to be decrypted Must be of length block_size(). Will hold the result when the function has finished.

Definition at line 74 of file block_cipher.h.

74 { decrypt_n(block, block, 1); }
virtual void decrypt_n(const byte in[], byte out[], size_t blocks) const =0
void Botan::XTEA::decrypt_n ( const byte  in[],
byte  out[],
size_t  blocks 
) const
virtual

Decrypt one or more blocks

Parameters
inthe input buffer (multiple of block_size())
outthe output buffer (same size as in)
blocksthe number of blocks to process

Implements Botan::BlockCipher.

Reimplemented in Botan::XTEA_SIMD.

Definition at line 93 of file xtea.cpp.

References Botan::Block_Cipher_Fixed_Params< 8, 16 >::BLOCK_SIZE, Botan::load_be< u32bit >(), and Botan::store_be().

Referenced by Botan::XTEA_SIMD::decrypt_n().

94  {
95  while(blocks >= 4)
96  {
97  xtea_decrypt_4(in, out, &(this->EK[0]));
98  in += 4 * BLOCK_SIZE;
99  out += 4 * BLOCK_SIZE;
100  blocks -= 4;
101  }
102 
103  for(size_t i = 0; i != blocks; ++i)
104  {
105  u32bit L = load_be<u32bit>(in, 0);
106  u32bit R = load_be<u32bit>(in, 1);
107 
108  for(size_t j = 0; j != 32; ++j)
109  {
110  R -= (((L << 4) ^ (L >> 5)) + L) ^ EK[63 - 2*j];
111  L -= (((R << 4) ^ (R >> 5)) + R) ^ EK[62 - 2*j];
112  }
113 
114  store_be(out, L, R);
115 
116  in += BLOCK_SIZE;
117  out += BLOCK_SIZE;
118  }
119  }
u32bit load_be< u32bit >(const byte in[], size_t off)
Definition: loadstor.h:166
void store_be(u16bit in, byte out[2])
Definition: loadstor.h:412
unsigned int u32bit
Definition: types.h:32
void Botan::BlockCipher::encrypt ( const byte  in[],
byte  out[] 
) const
inlineinherited

Encrypt a block.

Parameters
inThe plaintext block to be encrypted as a byte array. Must be of length block_size().
outThe byte array designated to hold the encrypted block. Must be of length block_size().

Definition at line 47 of file block_cipher.h.

Referenced by Botan::aont_package(), Botan::aont_unpackage(), Botan::OFB::cipher(), Botan::DESX::encrypt_n(), Botan::CFB_Encryption::set_iv(), Botan::OFB::set_iv(), Botan::XTS_Encryption::set_iv(), Botan::CFB_Decryption::set_iv(), and Botan::XTS_Decryption::set_iv().

48  { encrypt_n(in, out, 1); }
virtual void encrypt_n(const byte in[], byte out[], size_t blocks) const =0
void Botan::BlockCipher::encrypt ( byte  block[]) const
inlineinherited

Encrypt a block.

Parameters
blockthe plaintext block to be encrypted Must be of length block_size(). Will hold the result when the function has finished.

Definition at line 66 of file block_cipher.h.

66 { encrypt_n(block, block, 1); }
virtual void encrypt_n(const byte in[], byte out[], size_t blocks) const =0
void Botan::XTEA::encrypt_n ( const byte  in[],
byte  out[],
size_t  blocks 
) const
virtual

Encrypt one or more blocks

Parameters
inthe input buffer (multiple of block_size())
outthe output buffer (same size as in)
blocksthe number of blocks to process

Implements Botan::BlockCipher.

Reimplemented in Botan::XTEA_SIMD.

Definition at line 62 of file xtea.cpp.

References Botan::Block_Cipher_Fixed_Params< 8, 16 >::BLOCK_SIZE, Botan::load_be< u32bit >(), and Botan::store_be().

Referenced by Botan::XTEA_SIMD::encrypt_n().

63  {
64  while(blocks >= 4)
65  {
66  xtea_encrypt_4(in, out, &(this->EK[0]));
67  in += 4 * BLOCK_SIZE;
68  out += 4 * BLOCK_SIZE;
69  blocks -= 4;
70  }
71 
72  for(size_t i = 0; i != blocks; ++i)
73  {
74  u32bit L = load_be<u32bit>(in, 0);
75  u32bit R = load_be<u32bit>(in, 1);
76 
77  for(size_t j = 0; j != 32; ++j)
78  {
79  L += (((R << 4) ^ (R >> 5)) + R) ^ EK[2*j];
80  R += (((L << 4) ^ (L >> 5)) + L) ^ EK[2*j+1];
81  }
82 
83  store_be(out, L, R);
84 
85  in += BLOCK_SIZE;
86  out += BLOCK_SIZE;
87  }
88  }
u32bit load_be< u32bit >(const byte in[], size_t off)
Definition: loadstor.h:166
void store_be(u16bit in, byte out[2])
Definition: loadstor.h:412
unsigned int u32bit
Definition: types.h:32
const SecureVector<u32bit>& Botan::XTEA::get_EK ( ) const
inlineprotected
Returns
const reference to the key schedule

Definition at line 33 of file xtea.h.

Referenced by Botan::XTEA_SIMD::decrypt_n(), and Botan::XTEA_SIMD::encrypt_n().

33 { return EK; }
Key_Length_Specification Botan::Block_Cipher_Fixed_Params< BS, KMIN, 0 , 1 >::key_spec ( ) const
inlinevirtualinherited
Returns
object describing limits on key size

Implements Botan::SymmetricAlgorithm.

Definition at line 110 of file block_cipher.h.

111  {
112  return Key_Length_Specification(KMIN, KMAX, KMOD);
113  }
size_t Botan::SymmetricAlgorithm::maximum_keylength ( ) const
inlineinherited
Returns
minimum allowed key length

Definition at line 33 of file sym_algo.h.

34  {
35  return key_spec().maximum_keylength();
36  }
size_t maximum_keylength() const
Definition: key_spec.h:69
virtual Key_Length_Specification key_spec() const =0
size_t Botan::SymmetricAlgorithm::minimum_keylength ( ) const
inlineinherited
Returns
maxmium allowed key length

Definition at line 41 of file sym_algo.h.

42  {
43  return key_spec().minimum_keylength();
44  }
size_t minimum_keylength() const
Definition: key_spec.h:61
virtual Key_Length_Specification key_spec() const =0
std::string Botan::XTEA::name ( ) const
inlinevirtual
Returns
name of this algorithm

Implements Botan::Algorithm.

Definition at line 25 of file xtea.h.

25 { return "XTEA"; }
size_t Botan::BlockCipher::parallel_bytes ( ) const
inlineinherited
Returns
prefererred parallelism of this cipher in bytes

Definition at line 35 of file block_cipher.h.

References block_size.

36  {
37  return parallelism() * block_size() * BOTAN_BLOCK_CIPHER_PAR_MULT;
38  }
virtual size_t parallelism() const
Definition: block_cipher.h:30
virtual size_t block_size() const =0
virtual size_t Botan::BlockCipher::parallelism ( ) const
inlinevirtualinherited
Returns
native parallelism of this cipher in blocks

Reimplemented in Botan::AES_256_NI, Botan::AES_192_NI, Botan::AES_128_NI, Botan::IDEA_SSE2, Botan::Noekeon_SIMD, Botan::Serpent_SIMD, and Botan::XTEA_SIMD.

Definition at line 30 of file block_cipher.h.

30 { return 1; }
void Botan::SymmetricAlgorithm::set_key ( const SymmetricKey key)
inlineinherited
void Botan::SymmetricAlgorithm::set_key ( const byte  key[],
size_t  length 
)
inlineinherited

Set the symmetric key of this object.

Parameters
keythe to be set as a byte array.
lengthin bytes of key param

Definition at line 68 of file sym_algo.h.

69  {
70  if(!valid_keylength(length))
71  throw Invalid_Key_Length(name(), length);
72  key_schedule(key, length);
73  }
bool valid_keylength(size_t length) const
Definition: sym_algo.h:51
virtual std::string name() const =0
bool Botan::SymmetricAlgorithm::valid_keylength ( size_t  length) const
inlineinherited

Check whether a given key length is valid for this algorithm.

Parameters
lengththe key length to be checked.
Returns
true if the key length is valid.

Definition at line 51 of file sym_algo.h.

Referenced by Botan::aont_package(), Botan::aont_unpackage(), Botan::HMAC_RNG::HMAC_RNG(), Botan::Lion::Lion(), Botan::Randpool::Randpool(), and Botan::EAX_Base::valid_keylength().

52  {
53  return key_spec().valid_keylength(length);
54  }
bool valid_keylength(size_t length) const
Definition: key_spec.h:51
virtual Key_Length_Specification key_spec() const =0

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