include/asterisk/aes.h

   1 /*
   2  * Asterisk -- An open source telephony toolkit.
   3  *
   4  * See http://www.asterisk.org for more information about
   5  * the Asterisk project. Please do not directly contact
   6  * any of the maintainers of this project for assistance;
   7  * the project provides a web site, mailing lists and IRC
   8  * channels for your use.
   9  */
  10
  11 /*
  12  ---------------------------------------------------------------------------
  13  Copyright (c) 2003, Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
  14  All rights reserved.
  15
  16  LICENSE TERMS
  17
  18  The free distribution and use of this software in both source and binary
  19  form is allowed (with or without changes) provided that:
  20
  21    1. distributions of this source code include the above copyright
  22       notice, this list of conditions and the following disclaimer;
  23
  24    2. distributions in binary form include the above copyright
  25       notice, this list of conditions and the following disclaimer
  26       in the documentation and/or other associated materials;
  27
  28    3. the copyright holder's name is not used to endorse products
  29       built using this software without specific written permission.
  30
  31  ALTERNATIVELY, provided that this notice is retained in full, this product
  32  may be distributed under the terms of the GNU General Public License (GPL),
  33  in which case the provisions of the GPL apply INSTEAD OF those given above.
  34
  35  DISCLAIMER
  36
  37  This software is provided 'as is' with no explicit or implied warranties
  38  in respect of its properties, including, but not limited to, correctness
  39  and/or fitness for purpose.
  40  ---------------------------------------------------------------------------
  41  Issue Date: 26/08/2003
  42 */
  43 /*!\file
  44
  45  \brief This file contains the definitions required to use AES in C. See aesopt.h
  46  for optimisation details.
  47 */
  48
  49 #ifndef _AES_H
  50 #define _AES_H
  51
  52 /*  This include is used to find 8 & 32 bit unsigned integer types  */
  53 #include "limits.h"
  54
  55 #if defined(__cplusplus)
  56 extern "C"
  57 {
  58 #endif
  59
  60 #define AES_128     /* define if AES with 128 bit keys is needed    */
  61 #undef AES_192     /* define if AES with 192 bit keys is needed    */
  62 #undef AES_256     /* define if AES with 256 bit keys is needed    */
  63 #undef AES_VAR     /* define if a variable key size is needed      */
  64
  65 /* The following must also be set in assembler files if being used  */
  66
  67 #define AES_ENCRYPT /* if support for encryption is needed          */
  68 #define AES_DECRYPT /* if support for decryption is needed          */
  69 #define AES_ERR_CHK /* for parameter checks & error return codes    */
  70
  71 #if UCHAR_MAX == 0xff                   /* an unsigned 8 bit type   */
  72   typedef unsigned char      aes_08t;
  73 #else
  74 #error Please define aes_08t as an 8-bit unsigned integer type in aes.h
  75 #endif
  76
  77 #if UINT_MAX == 0xffffffff              /* an unsigned 32 bit type  */
  78   typedef   unsigned int     aes_32t;
  79 #elif ULONG_MAX == 0xffffffff
  80   typedef   unsigned long    aes_32t;
  81 #else
  82 #error Please define aes_32t as a 32-bit unsigned integer type in aes.h
  83 #endif
  84
  85 #define AES_BLOCK_SIZE  16  /* the AES block size in bytes          */
  86 #define N_COLS           4  /* the number of columns in the state   */
  87
  88 /* a maximum of 60 32-bit words are needed for the key schedule but */
  89 /* 64 are claimed to allow space at the top for a CBC xor buffer.   */
  90 /* If this is not needed, this value can be reduced to 60. A value  */
  91 /* of 64 may also help in maintaining alignment in some situations  */
  92 #define KS_LENGTH       64
  93
  94 #ifdef  AES_ERR_CHK
  95 #define aes_ret     int
  96 #define aes_good    0
  97 #define aes_error  -1
  98 #else
  99 #define aes_ret     void
 100 #endif
 101
 102 #ifndef AES_DLL                 /* implement normal/DLL functions   */
 103 #define aes_rval    aes_ret
 104 #else
 105 #define aes_rval    aes_ret __declspec(dllexport) _stdcall
 106 #endif
 107
 108 /* This routine must be called before first use if non-static       */
 109 /* tables are being used                                            */
 110
 111 void gen_tabs(void);
 112
 113 /* The key length (klen) is input in bytes when it is in the range  */
 114 /* 16 <= klen <= 32 or in bits when in the range 128 <= klen <= 256 */
 115
 116 #ifdef  AES_ENCRYPT
 117
 118 typedef struct
 119 {   aes_32t ks[KS_LENGTH];
 120 } aes_encrypt_ctx;
 121
 122 #if defined(AES_128) || defined(AES_VAR)
 123 aes_rval aes_encrypt_key128(const void *in_key, aes_encrypt_ctx cx[1]);
 124 #endif
 125
 126 #if defined(AES_192) || defined(AES_VAR)
 127 aes_rval aes_encrypt_key192(const void *in_key, aes_encrypt_ctx cx[1]);
 128 #endif
 129
 130 #if defined(AES_256) || defined(AES_VAR)
 131 aes_rval aes_encrypt_key256(const void *in_key, aes_encrypt_ctx cx[1]);
 132 #endif
 133
 134 #if defined(AES_VAR)
 135 aes_rval aes_encrypt_key(const void *in_key, int key_len, aes_encrypt_ctx cx[1]);
 136 #endif
 137
 138 aes_rval aes_encrypt(const void *in_blk, void *out_blk, const aes_encrypt_ctx cx[1]);
 139 #endif
 140
 141 #ifdef AES_DECRYPT
 142
 143 typedef struct
 144 {   aes_32t ks[KS_LENGTH];
 145 } aes_decrypt_ctx;
 146
 147 #if defined(AES_128) || defined(AES_VAR)
 148 aes_rval aes_decrypt_key128(const void *in_key, aes_decrypt_ctx cx[1]);
 149 #endif
 150
 151 #if defined(AES_192) || defined(AES_VAR)
 152 aes_rval aes_decrypt_key192(const void *in_key, aes_decrypt_ctx cx[1]);
 153 #endif
 154
 155 #if defined(AES_256) || defined(AES_VAR)
 156 aes_rval aes_decrypt_key256(const void *in_key, aes_decrypt_ctx cx[1]);
 157 #endif
 158
 159 #if defined(AES_VAR)
 160 aes_rval aes_decrypt_key(const void *in_key, int key_len, aes_decrypt_ctx cx[1]);
 161 #endif
 162
 163 aes_rval aes_decrypt(const void *in_blk, void *out_blk, const aes_decrypt_ctx cx[1]);
 164 #endif
 165
 166 #if defined(__cplusplus)
 167 }
 168 #endif
 169
 170 #endif