Botan  1.10.9
Public Types | Public Member Functions | List of all members
Botan::RC5 Class Reference

#include <rc5.h>

Inheritance diagram for Botan::RC5:
Botan::Block_Cipher_Fixed_Params< 8, 1, 32 > Botan::BlockCipher Botan::SymmetricAlgorithm Botan::Algorithm

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
 
 RC5 (size_t rounds)
 
void set_key (const SymmetricKey &key)
 
void set_key (const byte key[], size_t length)
 
bool valid_keylength (size_t length) const
 

Detailed Description

RC5

Definition at line 18 of file rc5.h.

Member Enumeration Documentation

anonymous enum
inherited

Constructor & Destructor Documentation

Botan::RC5::RC5 ( size_t  rounds)
Parameters
roundsthe number of RC5 rounds to run. Must be between 8 and 32 and a multiple of 4.

Definition at line 125 of file rc5.cpp.

References Botan::to_string().

126  {
127  if(rounds < 8 || rounds > 32 || (rounds % 4 != 0))
128  throw Invalid_Argument("RC5: Invalid number of rounds " +
129  to_string(rounds));
130 
131  S.resize(2*rounds + 2);
132  }
void resize(size_t n)
Definition: secmem.h:211
std::invalid_argument Invalid_Argument
Definition: exceptn.h:20
std::string to_string(u64bit n, size_t min_len)
Definition: parsing.cpp:42

Member Function Documentation

size_t Botan::Block_Cipher_Fixed_Params< BS, KMIN, KMAX, 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::RC5::clear ( )
inlinevirtual

Zeroize internal state

Implements Botan::Algorithm.

Definition at line 24 of file rc5.h.

References Botan::zeroise().

24 { zeroise(S); }
void zeroise(MemoryRegion< T > &vec)
Definition: secmem.h:415
BlockCipher* Botan::RC5::clone ( ) const
inlinevirtual

Get a new object representing the same algorithm as *this

Implements Botan::BlockCipher.

Definition at line 26 of file rc5.h.

26 { return new RC5(get_rounds()); }
RC5(size_t rounds)
Definition: rc5.cpp:125
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::RC5::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 54 of file rc5.cpp.

References Botan::Block_Cipher_Fixed_Params< 8, 1, 32 >::BLOCK_SIZE, Botan::load_le< u32bit >(), Botan::rotate_right(), Botan::MemoryRegion< T >::size(), and Botan::store_le().

55  {
56  const size_t rounds = (S.size() - 2) / 2;
57 
58  for(size_t i = 0; i != blocks; ++i)
59  {
60  u32bit A = load_le<u32bit>(in, 0);
61  u32bit B = load_le<u32bit>(in, 1);
62 
63  for(size_t j = rounds; j != 0; j -= 4)
64  {
65  B = rotate_right(B - S[2*j+1], A % 32) ^ A;
66  A = rotate_right(A - S[2*j ], B % 32) ^ B;
67 
68  B = rotate_right(B - S[2*j-1], A % 32) ^ A;
69  A = rotate_right(A - S[2*j-2], B % 32) ^ B;
70 
71  B = rotate_right(B - S[2*j-3], A % 32) ^ A;
72  A = rotate_right(A - S[2*j-4], B % 32) ^ B;
73 
74  B = rotate_right(B - S[2*j-5], A % 32) ^ A;
75  A = rotate_right(A - S[2*j-6], B % 32) ^ B;
76  }
77  B -= S[1]; A -= S[0];
78 
79  store_le(out, A, B);
80 
81  in += BLOCK_SIZE;
82  out += BLOCK_SIZE;
83  }
84  }
void store_le(u16bit in, byte out[2])
Definition: loadstor.h:427
T rotate_right(T input, size_t rot)
Definition: rotate.h:34
u32bit load_le< u32bit >(const byte in[], size_t off)
Definition: loadstor.h:183
size_t size() const
Definition: secmem.h:29
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::RC5::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 19 of file rc5.cpp.

References Botan::Block_Cipher_Fixed_Params< 8, 1, 32 >::BLOCK_SIZE, Botan::load_le< u32bit >(), Botan::rotate_left(), Botan::MemoryRegion< T >::size(), and Botan::store_le().

20  {
21  const size_t rounds = (S.size() - 2) / 2;
22 
23  for(size_t i = 0; i != blocks; ++i)
24  {
25  u32bit A = load_le<u32bit>(in, 0);
26  u32bit B = load_le<u32bit>(in, 1);
27 
28  A += S[0]; B += S[1];
29  for(size_t j = 0; j != rounds; j += 4)
30  {
31  A = rotate_left(A ^ B, B % 32) + S[2*j+2];
32  B = rotate_left(B ^ A, A % 32) + S[2*j+3];
33 
34  A = rotate_left(A ^ B, B % 32) + S[2*j+4];
35  B = rotate_left(B ^ A, A % 32) + S[2*j+5];
36 
37  A = rotate_left(A ^ B, B % 32) + S[2*j+6];
38  B = rotate_left(B ^ A, A % 32) + S[2*j+7];
39 
40  A = rotate_left(A ^ B, B % 32) + S[2*j+8];
41  B = rotate_left(B ^ A, A % 32) + S[2*j+9];
42  }
43 
44  store_le(out, A, B);
45 
46  in += BLOCK_SIZE;
47  out += BLOCK_SIZE;
48  }
49  }
void store_le(u16bit in, byte out[2])
Definition: loadstor.h:427
T rotate_left(T input, size_t rot)
Definition: rotate.h:21
u32bit load_le< u32bit >(const byte in[], size_t off)
Definition: loadstor.h:183
size_t size() const
Definition: secmem.h:29
unsigned int u32bit
Definition: types.h:32
Key_Length_Specification Botan::Block_Cipher_Fixed_Params< BS, KMIN, KMAX, 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::RC5::name ( ) const
virtual
Returns
name of this algorithm

Implements Botan::Algorithm.

Definition at line 117 of file rc5.cpp.

References Botan::to_string().

118  {
119  return "RC5(" + to_string(get_rounds()) + ")";
120  }
std::string to_string(u64bit n, size_t min_len)
Definition: parsing.cpp:42
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: