2
---------------------------------------------------------------------------
3
Copyright (c) 1998-2007, Brian Gladman, Worcester, UK. All rights reserved.
7
The free distribution and use of this software is allowed (with or without
8
changes) provided that:
10
1. source code distributions include the above copyright notice, this
11
list of conditions and the following disclaimer;
13
2. binary distributions include the above copyright notice, this list
14
of conditions and the following disclaimer in their documentation;
16
3. the name of the copyright holder is not used to endorse products
17
built using this software without specific written permission.
21
This software is provided 'as is' with no explicit or implied warranties
22
in respect of its properties, including, but not limited to, correctness
23
and/or fitness for purpose.
24
---------------------------------------------------------------------------
25
Issue Date: 20/12/2007
27
This file contains the definitions required to use AES in C. See aesopt.h
28
for optimisation details.
36
/* This include is used to find 8 & 32 bit unsigned integer types */
37
#include "brg_types.h"
39
#if defined(__cplusplus)
44
#define AES_128 /* if a fast 128 bit key scheduler is needed */
45
#define AES_192 /* if a fast 192 bit key scheduler is needed */
46
#define AES_256 /* if a fast 256 bit key scheduler is needed */
47
#define AES_VAR /* if variable key size scheduler is needed */
48
#define AES_MODES /* if support is needed for modes */
50
/* The following must also be set in assembler files if being used */
52
#define AES_ENCRYPT /* if support for encryption is needed */
53
#define AES_DECRYPT /* if support for decryption is needed */
54
#define AES_REV_DKS /* define to reverse decryption key schedule */
56
#define AES_BLOCK_SIZE 16 /* the AES block size in bytes */
57
#define N_COLS 4 /* the number of columns in the state */
59
/* The key schedule length is 11, 13 or 15 16-byte blocks for 128, */
60
/* 192 or 256-bit keys respectively. That is 176, 208 or 240 bytes */
61
/* or 44, 52 or 60 32-bit words. */
63
#if defined( AES_VAR ) || defined( AES_256 )
65
#elif defined( AES_192 )
71
#define AES_RETURN INT_RETURN
73
/* the character array 'inf' in the following structures is used */
74
/* to hold AES context information. This AES code uses cx->inf.b[0] */
75
/* to hold the number of rounds multiplied by 16. The other three */
76
/* elements can be used by code that implements additional modes */
84
{ uint_32t ks[KS_LENGTH];
89
{ uint_32t ks[KS_LENGTH];
93
/* This routine must be called before first use if non-static */
94
/* tables are being used */
96
AES_RETURN aes_init(void);
98
/* Key lengths in the range 16 <= key_len <= 32 are given in bytes, */
99
/* those in the range 128 <= key_len <= 256 are given in bits */
101
#if defined( AES_ENCRYPT )
103
#if defined( AES_128 ) || defined( AES_VAR)
104
AES_RETURN aes_encrypt_key128(const unsigned char *key, aes_encrypt_ctx cx[1]);
107
#if defined( AES_192 ) || defined( AES_VAR)
108
AES_RETURN aes_encrypt_key192(const unsigned char *key, aes_encrypt_ctx cx[1]);
111
#if defined( AES_256 ) || defined( AES_VAR)
112
AES_RETURN aes_encrypt_key256(const unsigned char *key, aes_encrypt_ctx cx[1]);
115
#if defined( AES_VAR )
116
AES_RETURN aes_encrypt_key(const unsigned char *key, int key_len, aes_encrypt_ctx cx[1]);
119
AES_RETURN aes_encrypt(const unsigned char *in, unsigned char *out, const aes_encrypt_ctx cx[1]);
123
#if defined( AES_DECRYPT )
125
#if defined( AES_128 ) || defined( AES_VAR)
126
AES_RETURN aes_decrypt_key128(const unsigned char *key, aes_decrypt_ctx cx[1]);
129
#if defined( AES_192 ) || defined( AES_VAR)
130
AES_RETURN aes_decrypt_key192(const unsigned char *key, aes_decrypt_ctx cx[1]);
133
#if defined( AES_256 ) || defined( AES_VAR)
134
AES_RETURN aes_decrypt_key256(const unsigned char *key, aes_decrypt_ctx cx[1]);
137
#if defined( AES_VAR )
138
AES_RETURN aes_decrypt_key(const unsigned char *key, int key_len, aes_decrypt_ctx cx[1]);
141
AES_RETURN aes_decrypt(const unsigned char *in, unsigned char *out, const aes_decrypt_ctx cx[1]);
145
#if defined( AES_MODES )
147
/* Multiple calls to the following subroutines for multiple block */
148
/* ECB, CBC, CFB, OFB and CTR mode encryption can be used to handle */
149
/* long messages incremantally provided that the context AND the iv */
150
/* are preserved between all such calls. For the ECB and CBC modes */
151
/* each individual call within a series of incremental calls must */
152
/* process only full blocks (i.e. len must be a multiple of 16) but */
153
/* the CFB, OFB and CTR mode calls can handle multiple incremental */
154
/* calls of any length. Each mode is reset when a new AES key is */
155
/* set but ECB and CBC operations can be reset without setting a */
156
/* new key by setting a new IV value. To reset CFB, OFB and CTR */
157
/* without setting the key, aes_mode_reset() must be called and the */
158
/* IV must be set. NOTE: All these calls update the IV on exit so */
159
/* this has to be reset if a new operation with the same IV as the */
160
/* previous one is required (or decryption follows encryption with */
161
/* the same IV array). */
163
AES_RETURN aes_test_alignment_detection(unsigned int n);
165
AES_RETURN aes_ecb_encrypt(const unsigned char *ibuf, unsigned char *obuf,
166
int len, const aes_encrypt_ctx cx[1]);
168
AES_RETURN aes_ecb_decrypt(const unsigned char *ibuf, unsigned char *obuf,
169
int len, const aes_decrypt_ctx cx[1]);
171
AES_RETURN aes_cbc_encrypt(const unsigned char *ibuf, unsigned char *obuf,
172
int len, unsigned char *iv, const aes_encrypt_ctx cx[1]);
174
AES_RETURN aes_cbc_decrypt(const unsigned char *ibuf, unsigned char *obuf,
175
int len, unsigned char *iv, const aes_decrypt_ctx cx[1]);
177
AES_RETURN aes_mode_reset(aes_encrypt_ctx cx[1]);
179
AES_RETURN aes_cfb_encrypt(const unsigned char *ibuf, unsigned char *obuf,
180
int len, unsigned char *iv, aes_encrypt_ctx cx[1]);
182
AES_RETURN aes_cfb_decrypt(const unsigned char *ibuf, unsigned char *obuf,
183
int len, unsigned char *iv, aes_encrypt_ctx cx[1]);
185
#define aes_ofb_encrypt aes_ofb_crypt
186
#define aes_ofb_decrypt aes_ofb_crypt
188
AES_RETURN aes_ofb_crypt(const unsigned char *ibuf, unsigned char *obuf,
189
int len, unsigned char *iv, aes_encrypt_ctx cx[1]);
191
typedef void cbuf_inc(unsigned char *cbuf);
193
#define aes_ctr_encrypt aes_ctr_crypt
194
#define aes_ctr_decrypt aes_ctr_crypt
196
AES_RETURN aes_ctr_crypt(const unsigned char *ibuf, unsigned char *obuf,
197
int len, unsigned char *cbuf, cbuf_inc ctr_inc, aes_encrypt_ctx cx[1]);
201
#if defined(__cplusplus)