Botan  1.10.9
Public Member Functions | List of all members
Botan::LubyRackoff Class Reference

#include <lubyrack.h>

Inheritance diagram for Botan::LubyRackoff:
Botan::BlockCipher Botan::SymmetricAlgorithm Botan::Algorithm

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
 
 LubyRackoff (HashFunction *hash)
 
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
 
 ~LubyRackoff ()
 

Detailed Description

Luby-Rackoff block cipher construction

Definition at line 19 of file lubyrack.h.

Constructor & Destructor Documentation

Botan::LubyRackoff::LubyRackoff ( HashFunction hash)
Parameters
hashfunction to use to form the block cipher

Definition at line 127 of file lubyrack.cpp.

Referenced by clone().

127  : hash(h)
128  {
129  }
Botan::LubyRackoff::~LubyRackoff ( )
inline

Definition at line 40 of file lubyrack.h.

40 { delete hash; }

Member Function Documentation

size_t Botan::LubyRackoff::block_size ( ) const
inlinevirtual
Returns
block size of this algorithm

Implements Botan::BlockCipher.

Definition at line 25 of file lubyrack.h.

25 { return 2 * hash->output_length(); }
virtual size_t output_length() const =0
void Botan::LubyRackoff::clear ( )
virtual

Zeroize internal state

Implements Botan::Algorithm.

Definition at line 101 of file lubyrack.cpp.

References Botan::Algorithm::clear(), and Botan::zeroise().

102  {
103  zeroise(K1);
104  zeroise(K2);
105  hash->clear();
106  }
virtual void clear()=0
void zeroise(MemoryRegion< T > &vec)
Definition: secmem.h:415
BlockCipher * Botan::LubyRackoff::clone ( ) const
virtual

Get a new object representing the same algorithm as *this

Implements Botan::BlockCipher.

Definition at line 111 of file lubyrack.cpp.

References Botan::HashFunction::clone(), and LubyRackoff().

112  {
113  return new LubyRackoff(hash->clone());
114  }
LubyRackoff(HashFunction *hash)
Definition: lubyrack.cpp:127
virtual HashFunction * clone() const =0
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::LubyRackoff::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.

Definition at line 53 of file lubyrack.cpp.

References Botan::Buffered_Computation::final(), Botan::Buffered_Computation::output_length(), Botan::Buffered_Computation::update(), and Botan::xor_buf().

54  {
55  const size_t len = hash->output_length();
56 
57  SecureVector<byte> buffer_vec(len);
58  byte* buffer = &buffer_vec[0];
59 
60  for(size_t i = 0; i != blocks; ++i)
61  {
62  hash->update(K2);
63  hash->update(in + len, len);
64  hash->final(buffer);
65  xor_buf(out, in, buffer, len);
66 
67  hash->update(K1);
68  hash->update(out, len);
69  hash->final(buffer);
70  xor_buf(out + len, in + len, buffer, len);
71 
72  hash->update(K2);
73  hash->update(out + len, len);
74  hash->final(buffer);
75  xor_buf(out, buffer, len);
76 
77  hash->update(K1);
78  hash->update(out, len);
79  hash->final(buffer);
80  xor_buf(out + len, buffer, len);
81 
82  in += 2 * len;
83  out += 2 * len;
84  }
85  }
unsigned char byte
Definition: types.h:22
void update(const byte in[], size_t length)
Definition: buf_comp.h:33
void final(byte out[])
Definition: buf_comp.h:80
void xor_buf(byte out[], const byte in[], size_t length)
Definition: xor_buf.h:21
virtual size_t output_length() const =0
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::LubyRackoff::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.

Definition at line 16 of file lubyrack.cpp.

References Botan::Buffered_Computation::final(), Botan::Buffered_Computation::output_length(), Botan::Buffered_Computation::update(), and Botan::xor_buf().

17  {
18  const size_t len = hash->output_length();
19 
20  SecureVector<byte> buffer_vec(len);
21  byte* buffer = &buffer_vec[0];
22 
23  for(size_t i = 0; i != blocks; ++i)
24  {
25  hash->update(K1);
26  hash->update(in, len);
27  hash->final(buffer);
28  xor_buf(out + len, in + len, buffer, len);
29 
30  hash->update(K2);
31  hash->update(out + len, len);
32  hash->final(buffer);
33  xor_buf(out, in, buffer, len);
34 
35  hash->update(K1);
36  hash->update(out, len);
37  hash->final(buffer);
38  xor_buf(out + len, buffer, len);
39 
40  hash->update(K2);
41  hash->update(out + len, len);
42  hash->final(buffer);
43  xor_buf(out, buffer, len);
44 
45  in += 2 * len;
46  out += 2 * len;
47  }
48  }
unsigned char byte
Definition: types.h:22
void update(const byte in[], size_t length)
Definition: buf_comp.h:33
void final(byte out[])
Definition: buf_comp.h:80
void xor_buf(byte out[], const byte in[], size_t length)
Definition: xor_buf.h:21
virtual size_t output_length() const =0
Key_Length_Specification Botan::LubyRackoff::key_spec ( ) const
inlinevirtual
Returns
object describing limits on key size

Implements Botan::SymmetricAlgorithm.

Definition at line 27 of file lubyrack.h.

28  {
29  return Key_Length_Specification(2, 32, 2);
30  }
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::LubyRackoff::name ( ) const
virtual
Returns
name of this algorithm

Implements Botan::Algorithm.

Definition at line 119 of file lubyrack.cpp.

References Botan::Algorithm::name().

120  {
121  return "Luby-Rackoff(" + hash->name() + ")";
122  }
virtual std::string name() const =0
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: