aboutsummaryrefslogtreecommitdiffstats
path: root/lib/block/block_cipher.h
blob: 5cbd6bdae6ac679f4dfc670c3df6f905119a5295 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
/*
* Block Cipher Base Class
* (C) 1999-2009 Jack Lloyd
*
* Distributed under the terms of the Botan license
*/

#ifndef BOTAN_BLOCK_CIPHER_H__
#define BOTAN_BLOCK_CIPHER_H__

#include <botan/sym_algo.h>

namespace Botan {

/**
* This class represents a block cipher object.
*/
class BOTAN_DLL BlockCipher : public SymmetricAlgorithm
   {
   public:

      /**
      * @return block size of this algorithm
      */
      virtual size_t block_size() const = 0;

      /**
      * @return native parallelism of this cipher in blocks
      */
      virtual size_t parallelism() const { return 1; }

      /**
      * @return prefererred parallelism of this cipher in bytes
      */
      size_t parallel_bytes() const
         {
         return parallelism() * block_size() * BOTAN_BLOCK_CIPHER_PAR_MULT;
         }

      /**
      * Encrypt a block.
      * @param in The plaintext block to be encrypted as a byte array.
      * Must be of length block_size().
      * @param out The byte array designated to hold the encrypted block.
      * Must be of length block_size().
      */
      void encrypt(const byte in[], byte out[]) const
         { encrypt_n(in, out, 1); }

      /**
      * Decrypt a block.
      * @param in The ciphertext block to be decypted as a byte array.
      * Must be of length block_size().
      * @param out The byte array designated to hold the decrypted block.
      * Must be of length block_size().
      */
      void decrypt(const byte in[], byte out[]) const
         { decrypt_n(in, out, 1); }

      /**
      * Encrypt a block.
      * @param block the plaintext block to be encrypted
      * Must be of length block_size(). Will hold the result when the function
      * has finished.
      */
      void encrypt(byte block[]) const { encrypt_n(block, block, 1); }

      /**
      * Decrypt a block.
      * @param block the ciphertext block to be decrypted
      * Must be of length block_size(). Will hold the result when the function
      * has finished.
      */
      void decrypt(byte block[]) const { decrypt_n(block, block, 1); }

      /**
      * Encrypt one or more blocks
      * @param block the input/output buffer (multiple of block_size())
      */
      template<typename Alloc>
      void encrypt(std::vector<byte, Alloc>& block) const
         {
         return encrypt_n(&block[0], &block[0], block.size() / block_size());
         }

      /**
      * Decrypt one or more blocks
      * @param block the input/output buffer (multiple of block_size())
      */
      template<typename Alloc>
      void decrypt(std::vector<byte, Alloc>& block) const
         {
         return decrypt_n(&block[0], &block[0], block.size() / block_size());
         }

      /**
      * Encrypt one or more blocks
      * @param in the input buffer (multiple of block_size())
      * @param out the output buffer (same size as in)
      */
      template<typename Alloc, typename Alloc2>
      void encrypt(const std::vector<byte, Alloc>& in,
                   std::vector<byte, Alloc2>& out) const
         {
         return encrypt_n(&in[0], &out[0], in.size() / block_size());
         }

      /**
      * Decrypt one or more blocks
      * @param in the input buffer (multiple of block_size())
      * @param out the output buffer (same size as in)
      */
      template<typename Alloc, typename Alloc2>
      void decrypt(const std::vector<byte, Alloc>& in,
                   std::vector<byte, Alloc2>& out) const
         {
         return decrypt_n(&in[0], &out[0], in.size() / block_size());
         }

      /**
      * Encrypt one or more blocks
      * @param in the input buffer (multiple of block_size())
      * @param out the output buffer (same size as in)
      * @param blocks the number of blocks to process
      */
      virtual void encrypt_n(const byte in[], byte out[],
                             size_t blocks) const = 0;

      /**
      * Decrypt one or more blocks
      * @param in the input buffer (multiple of block_size())
      * @param out the output buffer (same size as in)
      * @param blocks the number of blocks to process
      */
      virtual void decrypt_n(const byte in[], byte out[],
                             size_t blocks) const = 0;

      /**
      * @return new object representing the same algorithm as *this
      */
      virtual BlockCipher* clone() const = 0;
   };

/**
* Represents a block cipher with a single fixed block size
*/
template<size_t BS, size_t KMIN, size_t KMAX = 0, size_t KMOD = 1>
class Block_Cipher_Fixed_Params : public BlockCipher
   {
   public:
      enum { BLOCK_SIZE = BS };
      size_t block_size() const { return BS; }

      Key_Length_Specification key_spec() const
         {
         return Key_Length_Specification(KMIN, KMAX, KMOD);
         }
   };

}

#endif