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/* 
 --------------------------------------------------------------------------- 
 Copyright (c) 2003, Dr Brian Gladman, Worcester, UK.   All rights reserved. 
 
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      in the documentation and/or other associated materials; 
 
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 ALTERNATIVELY, provided that this notice is retained in full, this product 
 may be distributed under the terms of the GNU General Public License (GPL), 
 in which case the provisions of the GPL apply INSTEAD OF those given above. 
 
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 Issue 01/08/2005 
 
 This file contains the compilation options for AES (Rijndael) and code 
 that is common across encryption, key scheduling and table generation. 
 
 OPERATION 
 
 These source code files implement the AES algorithm Rijndael designed by 
 Joan Daemen and Vincent Rijmen. This version is designed for the standard 
 block size of 16 bytes and for key sizes of 128, 192 and 256 bits (16, 24 
 and 32 bytes). 
 
 This version is designed for flexibility and speed using operations on 
 32-bit words rather than operations on bytes.  It can be compiled with 
 either big or little endian internal byte order but is faster when the 
 native byte order for the processor is used. 
 
 THE CIPHER INTERFACE 
 
 The cipher interface is implemented as an array of bytes in which lower 
 AES bit sequence indexes map to higher numeric significance within bytes. 
 
  uint_8t                 (an unsigned  8-bit type) 
  uint_32t                 (an unsigned 32-bit type) 
  struct aes_encrypt_ctx  (structure for the cipher encryption context) 
  struct aes_decrypt_ctx  (structure for the cipher decryption context) 
  aes_rval                the function return type 
 
  C subroutine calls: 
 
  aes_rval aes_encrypt_key128(const unsigned char *key, aes_encrypt_ctx cx[1]); 
  aes_rval aes_encrypt_key192(const unsigned char *key, aes_encrypt_ctx cx[1]); 
  aes_rval aes_encrypt_key256(const unsigned char *key, aes_encrypt_ctx cx[1]); 
  aes_rval aes_encrypt(const unsigned char *in, unsigned char *out, 
                                                  const aes_encrypt_ctx cx[1]); 
 
  aes_rval aes_decrypt_key128(const unsigned char *key, aes_decrypt_ctx cx[1]); 
  aes_rval aes_decrypt_key192(const unsigned char *key, aes_decrypt_ctx cx[1]); 
  aes_rval aes_decrypt_key256(const unsigned char *key, aes_decrypt_ctx cx[1]); 
  aes_rval aes_decrypt(const unsigned char *in, unsigned char *out, 
                                                  const aes_decrypt_ctx cx[1]); 
 
 IMPORTANT NOTE: If you are using this C interface with dynamic tables make sure that 
 you call genTabs() before AES is used so that the tables are initialised. 
 
 C++ aes class subroutines: 
 
     Class AESencrypt  for encryption 
 
      Construtors: 
          AESencrypt(void) 
          AESencrypt(const unsigned char *key) - 128 bit key 
      Members: 
          aes_rval key128(const unsigned char *key) 
          aes_rval key192(const unsigned char *key) 
          aes_rval key256(const unsigned char *key) 
          aes_rval encrypt(const unsigned char *in, unsigned char *out) const 
 
      Class AESdecrypt  for encryption 
      Construtors: 
          AESdecrypt(void) 
          AESdecrypt(const unsigned char *key) - 128 bit key 
      Members: 
          aes_rval key128(const unsigned char *key) 
          aes_rval key192(const unsigned char *key) 
          aes_rval key256(const unsigned char *key) 
          aes_rval decrypt(const unsigned char *in, unsigned char *out) const 
 
    COMPILATION 
 
    The files used to provide AES (Rijndael) are 
 
    a. aes.h for the definitions needed for use in C. 
    b. aescpp.h for the definitions needed for use in C++. 
    c. aesopt.h for setting compilation options (also includes common code). 
    d. aescrypt.c for encryption and decrytpion, or 
    e. aeskey.c for key scheduling. 
    f. aestab.c for table loading or generation. 
    g. aescrypt.asm for encryption and decryption using assembler code. 
    h. aescrypt.mmx.asm for encryption and decryption using MMX assembler. 
 
    To compile AES (Rijndael) for use in C code use aes.h and set the 
    defines here for the facilities you need (key lengths, encryption 
    and/or decryption). Do not define BUILD_DLL or AES_CPP.  Set the options 
    for optimisations and table sizes here. 
 
    To compile AES (Rijndael) for use in in C++ code use aescpp.h but do 
    not define BUILD_DLL 
 
    To compile AES (Rijndael) in C as a Dynamic Link Library DLL) use 
    aes.h and include the BUILD_DLL define. 
 
    CONFIGURATION OPTIONS (here and in aes.h) 
 
    a. set BUILD_DLL in aes.h if AES (Rijndael) is to be compiled as a DLL 
    b. You may need to set PLATFORM_BYTE_ORDER to define the byte order. 
    c. If you want the code to run in a specific internal byte order, then 
       ALGORITHM_BYTE_ORDER must be set accordingly. 
    d. set other configuration options decribed below. 
*/ 
 
/* Adapted for TrueCrypt by the TrueCrypt Foundation */ 
 
#if !defined( _AESOPT_H ) 
#define _AESOPT_H 
 
#if defined( __cplusplus ) && defined( AES_CPP ) 
#include "aescpp.h" 
#else 
#include "Aes.h" 
#endif 
 
/*  PLATFORM SPECIFIC INCLUDES */ 
 
#include "Endian.h" 
#define IS_LITTLE_ENDIAN   1234 /* byte 0 is least significant (i386) */ 
#define IS_BIG_ENDIAN      4321 /* byte 0 is most significant (mc68k) */ 
 
#if BYTE_ORDER == LITTLE_ENDIAN 
#  define PLATFORM_BYTE_ORDER IS_LITTLE_ENDIAN 
#endif 
 
#if BYTE_ORDER == BIG_ENDIAN 
#  define PLATFORM_BYTE_ORDER IS_BIG_ENDIAN 
#endif 
 
 
/*  CONFIGURATION - THE USE OF DEFINES 
 
    Later in this section there are a number of defines that control the 
    operation of the code.  In each section, the purpose of each define is 
    explained so that the relevant form can be included or excluded by 
    setting either 1's or 0's respectively on the branches of the related 
    #if clauses.  The following local defines should not be changed. 
*/ 
 
#define ENCRYPTION_IN_C     1 
#define DECRYPTION_IN_C     2 
#define ENC_KEYING_IN_C     4 
#define DEC_KEYING_IN_C     8 
 
#define ENCRYPTION_IN_ASM  16 
#define DECRYPTION_IN_ASM  32 
#define ENC_KEYING_IN_ASM  64 
#define DEC_KEYING_IN_ASM 128 
 
#define NO_TABLES           0 
#define ONE_TABLE           1 
#define FOUR_TABLES         4 
#define NONE                0 
#define PARTIAL             1 
#define FULL                2 
 
/*  1. BYTE ORDER WITHIN 32 BIT WORDS 
 
    The fundamental data processing units in Rijndael are 8-bit bytes. The 
    input, output and key input are all enumerated arrays of bytes in which 
    bytes are numbered starting at zero and increasing to one less than the 
    number of bytes in the array in question. This enumeration is only used 
    for naming bytes and does not imply any adjacency or order relationship 
    from one byte to another. When these inputs and outputs are considered 
    as bit sequences, bits 8*n to 8*n+7 of the bit sequence are mapped to 
    byte[n] with bit 8n+i in the sequence mapped to bit 7-i within the byte. 
    In this implementation bits are numbered from 0 to 7 starting at the 
    numerically least significant end of each byte (bit n represents 2^n). 
 
    However, Rijndael can be implemented more efficiently using 32-bit 
    words by packing bytes into words so that bytes 4*n to 4*n+3 are placed 
    into word[n]. While in principle these bytes can be assembled into words 
    in any positions, this implementation only supports the two formats in 
    which bytes in adjacent positions within words also have adjacent byte 
    numbers. This order is called big-endian if the lowest numbered bytes 
    in words have the highest numeric significance and little-endian if the 
    opposite applies. 
 
    This code can work in either order irrespective of the order used by the 
    machine on which it runs. Normally the internal byte order will be set 
    to the order of the processor on which the code is to be run but this 
    define can be used to reverse this in special situations 
 
    WARNING: Assembler code versions rely on PLATFORM_BYTE_ORDER being set. 
    This define will hence be redefined later (in section 4) if necessary 
*/ 
 
#if 1  
#define ALGORITHM_BYTE_ORDER PLATFORM_BYTE_ORDER 
#elif 0 
#define ALGORITHM_BYTE_ORDER IS_LITTLE_ENDIAN 
#elif 0 
#define ALGORITHM_BYTE_ORDER IS_BIG_ENDIAN 
#else 
#error The algorithm byte order is not defined 
#endif 
 
/*  2. VIA ACE SUPPORT 
 
    Define this option if support for the VIA ACE is required. This uses  
    inline assembler instructions and is only implemented for the Microsoft,  
    Intel and GCC compilers.  If VIA ACE is known to be present, then defining 
    ASSUME_VIA_ACE_PRESENT will remove the ordinary encryption/decryption  
    code.  If USE_VIA_ACE_IF_PRESENT is defined then VIA ACE will be used if 
    it is detected (both present and enabled) but the normal AES code will  
    also be present.  
     
    When VIA ACE is to be used, all AES encryption contexts MUST be 16 byte  
    aligned; other input/output buffers do not need to be 16 byte aligned  
    but there are very large performance gains if this can be arranged.   
    VIA ACE also requires the decryption key schedule to be in reverse  
    order (which the following defines ensure). 
*/ 
 
#if 0 && !defined( USE_VIA_ACE_IF_PRESENT ) 
#define USE_VIA_ACE_IF_PRESENT 
#endif 
 
#if 0 && !defined( ASSUME_VIA_ACE_PRESENT ) 
#define ASSUME_VIA_ACE_PRESENT 
#endif 
 
#if !defined( _MSC_VER ) && !defined( __GNUC__ ) 
#  if defined( ASSUME_VIA_ACE_PRESENT ) 
#    undef ASSUME_VIA_ACE_PRESENT 
#  endif 
#  if defined( USE_VIA_ACE_IF_PRESENT ) 
#    undef USE_VIA_ACE_IF_PRESENT 
#  endif 
#endif 
 
#if defined( ASSUME_VIA_ACE_PRESENT ) && !defined( USE_VIA_ACE_IF_PRESENT ) 
#define USE_VIA_ACE_IF_PRESENT 
#endif 
 
#if defined( USE_VIA_ACE_IF_PRESENT ) && !defined ( AES_REV_DKS ) 
#define AES_REV_DKS 
#endif 
 
/*  3. ASSEMBLER SUPPORT 
 
    This define (which can be on the command line) enables the use of the 
    assembler code routines for encryption, decryption and key scheduling 
    as follows: 
 
        ASM_V1		uses the assembler (aescrypt1.asm) for large tables with 
                    tables and key scheduling in C 
        ASM_V2		uses assembler (aescrypt2.asm) with compressed tables  
                    and key scheduling 
        ASM_V2C		uses assembler (aescrypt2.asm) with compressed tables 
                    but uses key scheduling in C 
*/ 
 
#if 0 && !defined( ASM_V1 ) 
#define ASM_V1 
#elif 0 && !defined( ASM_V2 ) 
#define ASM_V2 
#elif 0 && !defined( ASM_V2C ) 
#define ASM_V2C 
#endif 
 
#if defined( ASM_V1 ) && (ALGORITHM_BYTE_ORDER != PLATFORM_BYTE_ORDER) 
#undef  ALGORITHM_BYTE_ORDER 
#define ALGORITHM_BYTE_ORDER PLATFORM_BYTE_ORDER 
#endif 
 
/*  4. FUNCTIONS REQUIRED 
 
    This implementation provides subroutines for encryption, decryption 
    and for setting the three key lengths (separately) for encryption 
    and decryption. When the assembler code is not being used the following 
    definition blocks allow the selection of the routines that are to be 
    included in the compilation. 
*/ 
 
#if !defined( AES_ENCRYPT ) 
#  define EFUNCS_IN_C   0 
#elif defined( USE_VIA_ACE_IF_PRESENT ) || defined( ASM_V1 ) 
#  define EFUNCS_IN_C   ENC_KEYING_IN_C 
#elif defined( ASM_V2C ) 
#  define EFUNCS_IN_C   ENC_KEYING_IN_C 
#elif !defined( ASM_V2 ) 
#  define EFUNCS_IN_C   ( ENCRYPTION_IN_C | ENC_KEYING_IN_C ) 
#else 
#  define EFUNCS_IN_C   0 
#endif 
 
#if !defined( AES_DECRYPT ) 
#  define DFUNCS_IN_C   0 
#elif defined( USE_VIA_ACE_IF_PRESENT ) || defined( ASM_V1 ) 
#  define DFUNCS_IN_C   DEC_KEYING_IN_C 
#elif defined( ASM_V2C ) 
#  define DFUNCS_IN_C   DEC_KEYING_IN_C 
#elif !defined( ASM_V2 ) 
#  define DFUNCS_IN_C   ( DECRYPTION_IN_C | DEC_KEYING_IN_C ) 
#else 
#  define DFUNCS_IN_C   0 
#endif 
 
#define FUNCS_IN_C  ( EFUNCS_IN_C | DFUNCS_IN_C ) 
 
/*  5. FAST INPUT/OUTPUT OPERATIONS. 
 
    On some machines it is possible to improve speed by transferring the 
    bytes in the input and output arrays to and from the internal 32-bit 
    variables by addressing these arrays as if they are arrays of 32-bit 
    words.  On some machines this will always be possible but there may 
    be a large performance penalty if the byte arrays are not aligned on 
    the normal word boundaries. On other machines this technique will 
    lead to memory access errors when such 32-bit word accesses are not 
    properly aligned. The option SAFE_IO avoids such problems but will 
    often be slower on those machines that support misaligned access 
    (especially so if care is taken to align the input  and output byte 
    arrays on 32-bit word boundaries). If SAFE_IO is not defined it is 
    assumed that access to byte arrays as if they are arrays of 32-bit 
    words will not cause problems when such accesses are misaligned. 
*/ 
#if 1 && !defined(_MSC_VER) 
#define SAFE_IO 
#endif 
 
/*  6. LOOP UNROLLING 
 
    The code for encryption and decrytpion cycles through a number of rounds 
    that can be implemented either in a loop or by expanding the code into a 
    long sequence of instructions, the latter producing a larger program but 
    one that will often be much faster. The latter is called loop unrolling. 
    There are also potential speed advantages in expanding two iterations in 
    a loop with half the number of iterations, which is called partial loop 
    unrolling.  The following options allow partial or full loop unrolling 
    to be set independently for encryption and decryption 
*/ 
#if 1 
#define ENC_UNROLL  FULL 
#elif 0 
#define ENC_UNROLL  PARTIAL 
#else 
#define ENC_UNROLL  NONE 
#endif 
 
#if 1 
#define DEC_UNROLL  FULL 
#elif 0 
#define DEC_UNROLL  PARTIAL 
#else 
#define DEC_UNROLL  NONE 
#endif 
 
/*  7. FAST FINITE FIELD OPERATIONS 
 
    If this section is included, tables are used to provide faster finite 
    field arithmetic (this has no effect if FIXED_TABLES is defined). 
*/ 
#if 1 
#define FF_TABLES 
#endif 
 
/*  8. INTERNAL STATE VARIABLE FORMAT 
 
    The internal state of Rijndael is stored in a number of local 32-bit 
    word varaibles which can be defined either as an array or as individual 
    names variables. Include this section if you want to store these local 
    varaibles in arrays. Otherwise individual local variables will be used. 
*/ 
#if 1 
#define ARRAYS 
#endif 
 
/* In this implementation the columns of the state array are each held in 
   32-bit words. The state array can be held in various ways: in an array 
   of words, in a number of individual word variables or in a number of 
   processor registers. The following define maps a variable name x and 
   a column number c to the way the state array variable is to be held. 
   The first define below maps the state into an array x[c] whereas the 
   second form maps the state into a number of individual variables x0, 
   x1, etc.  Another form could map individual state colums to machine 
   register names. 
*/ 
 
#if defined(ARRAYS) 
#define s(x,c) x[c] 
#else 
#define s(x,c) x##c 
#endif 
 
/*  9. FIXED OR DYNAMIC TABLES 
 
    When this section is included the tables used by the code are compiled 
    statically into the binary file.  Otherwise the subroutine gen_tabs() 
    must be called to compute them before the code is first used. 
*/ 
#if 1 
#define FIXED_TABLES 
#endif 
 
/*  10. TABLE ALIGNMENT 
 
    On some sytsems speed will be improved by aligning the AES large lookup 
    tables on particular boundaries. This define should be set to a power of 
    two giving the desired alignment. It can be left undefined if alignment 
    is not needed.  This option is specific to the Microsft VC++ compiler - 
    it seems to sometimes cause trouble for the VC++ version 6 compiler. 
*/ 
 
#if 1 && defined(_MSC_VER) && (_MSC_VER >= 1300) 
#define TABLE_ALIGN 32 
#endif 
 
/*  11. INTERNAL TABLE CONFIGURATION 
 
    This cipher proceeds by repeating in a number of cycles known as 'rounds' 
    which are implemented by a round function which can optionally be speeded 
    up using tables.  The basic tables are each 256 32-bit words, with either 
    one or four tables being required for each round function depending on 
    how much speed is required. The encryption and decryption round functions 
    are different and the last encryption and decrytpion round functions are 
    different again making four different round functions in all. 
 
    This means that: 
      1. Normal encryption and decryption rounds can each use either 0, 1 
         or 4 tables and table spaces of 0, 1024 or 4096 bytes each. 
      2. The last encryption and decryption rounds can also use either 0, 1 
         or 4 tables and table spaces of 0, 1024 or 4096 bytes each. 
 
    Include or exclude the appropriate definitions below to set the number 
    of tables used by this implementation. 
*/ 
 
#if 1   /* set tables for the normal encryption round */ 
#define ENC_ROUND   FOUR_TABLES 
#elif 0 
#define ENC_ROUND   ONE_TABLE 
#else 
#define ENC_ROUND   NO_TABLES 
#endif 
 
#if 1   /* set tables for the last encryption round */ 
#define LAST_ENC_ROUND  FOUR_TABLES 
#elif 0 
#define LAST_ENC_ROUND  ONE_TABLE 
#else 
#define LAST_ENC_ROUND  NO_TABLES 
#endif 
 
#if 1   /* set tables for the normal decryption round */ 
#define DEC_ROUND   FOUR_TABLES 
#elif 0 
#define DEC_ROUND   ONE_TABLE 
#else 
#define DEC_ROUND   NO_TABLES 
#endif 
 
#if 1   /* set tables for the last decryption round */ 
#define LAST_DEC_ROUND  FOUR_TABLES 
#elif 0 
#define LAST_DEC_ROUND  ONE_TABLE 
#else 
#define LAST_DEC_ROUND  NO_TABLES 
#endif 
 
/*  The decryption key schedule can be speeded up with tables in the same 
    way that the round functions can.  Include or exclude the following 
    defines to set this requirement. 
*/ 
#if 1 
#define KEY_SCHED   FOUR_TABLES 
#elif 0 
#define KEY_SCHED   ONE_TABLE 
#else 
#define KEY_SCHED   NO_TABLES 
#endif 
 
/* END OF CONFIGURATION OPTIONS */ 
 
#define RC_LENGTH   (5 * (AES_BLOCK_SIZE / 4 - 2)) 
 
/* Disable or report errors on some combinations of options */ 
 
#if ENC_ROUND == NO_TABLES && LAST_ENC_ROUND != NO_TABLES 
#undef  LAST_ENC_ROUND 
#define LAST_ENC_ROUND  NO_TABLES 
#elif ENC_ROUND == ONE_TABLE && LAST_ENC_ROUND == FOUR_TABLES 
#undef  LAST_ENC_ROUND 
#define LAST_ENC_ROUND  ONE_TABLE 
#endif 
 
#if ENC_ROUND == NO_TABLES && ENC_UNROLL != NONE 
#undef  ENC_UNROLL 
#define ENC_UNROLL  NONE 
#endif 
 
#if DEC_ROUND == NO_TABLES && LAST_DEC_ROUND != NO_TABLES 
#undef  LAST_DEC_ROUND 
#define LAST_DEC_ROUND  NO_TABLES 
#elif DEC_ROUND == ONE_TABLE && LAST_DEC_ROUND == FOUR_TABLES 
#undef  LAST_DEC_ROUND 
#define LAST_DEC_ROUND  ONE_TABLE 
#endif 
 
#if DEC_ROUND == NO_TABLES && DEC_UNROLL != NONE 
#undef  DEC_UNROLL 
#define DEC_UNROLL  NONE 
#endif 
 
#if defined(bswap32) 
#define aes_sw32    bswap32 
#elif defined(bswap_32) 
#define aes_sw32    bswap_32 
#else 
#define brot(x,n)   (((uint_32t)(x) <<  n) | ((uint_32t)(x) >> (32 - n))) 
#define aes_sw32(x) ((brot((x),8) & 0x00ff00ff) | (brot((x),24) & 0xff00ff00)) 
#endif 
 
/*  upr(x,n):  rotates bytes within words by n positions, moving bytes to 
               higher index positions with wrap around into low positions 
    ups(x,n):  moves bytes by n positions to higher index positions in 
               words but without wrap around 
    bval(x,n): extracts a byte from a word 
 
    WARNING:   The definitions given here are intended only for use with 
               unsigned variables and with shift counts that are compile 
               time constants 
*/ 
 
#if (ALGORITHM_BYTE_ORDER == IS_LITTLE_ENDIAN) 
#define upr(x,n)        (((uint_32t)(x) << (8 * (n))) | ((uint_32t)(x) >> (32 - 8 * (n)))) 
#define ups(x,n)        ((uint_32t) (x) << (8 * (n))) 
#define bval(x,n)       ((uint_8t)((x) >> (8 * (n)))) 
#define bytes2word(b0, b1, b2, b3)  \ 
        (((uint_32t)(b3) << 24) | ((uint_32t)(b2) << 16) | ((uint_32t)(b1) << 8) | (b0)) 
#endif 
 
#if (ALGORITHM_BYTE_ORDER == IS_BIG_ENDIAN) 
#define upr(x,n)        (((uint_32t)(x) >> (8 * (n))) | ((uint_32t)(x) << (32 - 8 * (n)))) 
#define ups(x,n)        ((uint_32t) (x) >> (8 * (n))) 
#define bval(x,n)       ((uint_8t)((x) >> (24 - 8 * (n)))) 
#define bytes2word(b0, b1, b2, b3)  \ 
        (((uint_32t)(b0) << 24) | ((uint_32t)(b1) << 16) | ((uint_32t)(b2) << 8) | (b3)) 
#endif 
 
#if defined(SAFE_IO) 
 
#define word_in(x,c)    bytes2word(((const uint_8t*)(x)+4*c)[0], ((const uint_8t*)(x)+4*c)[1], \ 
                                   ((const uint_8t*)(x)+4*c)[2], ((const uint_8t*)(x)+4*c)[3]) 
#define word_out(x,c,v) { ((uint_8t*)(x)+4*c)[0] = bval(v,0); ((uint_8t*)(x)+4*c)[1] = bval(v,1); \ 
                          ((uint_8t*)(x)+4*c)[2] = bval(v,2); ((uint_8t*)(x)+4*c)[3] = bval(v,3); } 
 
#elif (ALGORITHM_BYTE_ORDER == PLATFORM_BYTE_ORDER) 
 
#define word_in(x,c)    (*((uint_32t*)(x)+(c))) 
#define word_out(x,c,v) (*((uint_32t*)(x)+(c)) = (v)) 
 
#else 
 
#define word_in(x,c)    aes_sw32(*((uint_32t*)(x)+(c))) 
#define word_out(x,c,v) (*((uint_32t*)(x)+(c)) = aes_sw32(v)) 
 
#endif 
 
/* the finite field modular polynomial and elements */ 
 
#define WPOLY   0x011b 
#define BPOLY     0x1b 
 
/* multiply four bytes in GF(2^8) by 'x' {02} in parallel */ 
 
#define m1  0x80808080 
#define m2  0x7f7f7f7f 
#define gf_mulx(x)  ((((x) & m2) << 1) ^ ((((x) & m1) >> 7) * BPOLY)) 
 
/* The following defines provide alternative definitions of gf_mulx that might 
   give improved performance if a fast 32-bit multiply is not available. Note 
   that a temporary variable u needs to be defined where gf_mulx is used. 
 
#define gf_mulx(x) (u = (x) & m1, u |= (u >> 1), ((x) & m2) << 1) ^ ((u >> 3) | (u >> 6)) 
#define m4  (0x01010101 * BPOLY) 
#define gf_mulx(x) (u = (x) & m1, ((x) & m2) << 1) ^ ((u - (u >> 7)) & m4) 
*/ 
 
/* Work out which tables are needed for the different options   */ 
 
#if defined( ASM_V1 ) 
#if defined( ENC_ROUND ) 
#undef  ENC_ROUND 
#endif 
#define ENC_ROUND   FOUR_TABLES 
#if defined( LAST_ENC_ROUND ) 
#undef  LAST_ENC_ROUND 
#endif 
#define LAST_ENC_ROUND  FOUR_TABLES 
#if defined( DEC_ROUND ) 
#undef  DEC_ROUND 
#endif 
#define DEC_ROUND   FOUR_TABLES 
#if defined( LAST_DEC_ROUND ) 
#undef  LAST_DEC_ROUND 
#endif 
#define LAST_DEC_ROUND  FOUR_TABLES 
#if defined( KEY_SCHED ) 
#undef  KEY_SCHED 
#define KEY_SCHED   FOUR_TABLES 
#endif 
#endif 
 
#if (FUNCS_IN_C & ENCRYPTION_IN_C) || ASM_V1 
#if ENC_ROUND == ONE_TABLE 
#define FT1_SET 
#elif ENC_ROUND == FOUR_TABLES 
#define FT4_SET 
#else 
#define SBX_SET 
#endif 
#if LAST_ENC_ROUND == ONE_TABLE 
#define FL1_SET 
#elif LAST_ENC_ROUND == FOUR_TABLES 
#define FL4_SET 
#elif !defined(SBX_SET) 
#define SBX_SET 
#endif 
#endif 
 
#if (FUNCS_IN_C & DECRYPTION_IN_C) || ASM_V1 
#if DEC_ROUND == ONE_TABLE 
#define IT1_SET 
#elif DEC_ROUND == FOUR_TABLES 
#define IT4_SET 
#else 
#define ISB_SET 
#endif 
#if LAST_DEC_ROUND == ONE_TABLE 
#define IL1_SET 
#elif LAST_DEC_ROUND == FOUR_TABLES 
#define IL4_SET 
#elif !defined(ISB_SET) 
#define ISB_SET 
#endif 
#endif 
 
#if (FUNCS_IN_C & ENC_KEYING_IN_C) || (FUNCS_IN_C & DEC_KEYING_IN_C) 
#if KEY_SCHED == ONE_TABLE 
#define LS1_SET 
#elif KEY_SCHED == FOUR_TABLES 
#define LS4_SET 
#elif !defined(SBX_SET) 
#define SBX_SET 
#endif 
#endif 
 
#if (FUNCS_IN_C & DEC_KEYING_IN_C) 
#if KEY_SCHED == ONE_TABLE 
#define IM1_SET 
#elif KEY_SCHED == FOUR_TABLES 
#define IM4_SET 
#elif !defined(SBX_SET) 
#define SBX_SET 
#endif 
#endif 
 
/* generic definitions of Rijndael macros that use tables    */ 
 
#define no_table(x,box,vf,rf,c) bytes2word( \ 
    box[bval(vf(x,0,c),rf(0,c))], \ 
    box[bval(vf(x,1,c),rf(1,c))], \ 
    box[bval(vf(x,2,c),rf(2,c))], \ 
    box[bval(vf(x,3,c),rf(3,c))]) 
 
#define one_table(x,op,tab,vf,rf,c) \ 
 (     tab[bval(vf(x,0,c),rf(0,c))] \ 
  ^ op(tab[bval(vf(x,1,c),rf(1,c))],1) \ 
  ^ op(tab[bval(vf(x,2,c),rf(2,c))],2) \ 
  ^ op(tab[bval(vf(x,3,c),rf(3,c))],3)) 
 
#define four_tables(x,tab,vf,rf,c) \ 
 (  tab[0][bval(vf(x,0,c),rf(0,c))] \ 
  ^ tab[1][bval(vf(x,1,c),rf(1,c))] \ 
  ^ tab[2][bval(vf(x,2,c),rf(2,c))] \ 
  ^ tab[3][bval(vf(x,3,c),rf(3,c))]) 
 
#define vf1(x,r,c)  (x) 
#define rf1(r,c)    (r) 
#define rf2(r,c)    ((8+r-c)&3) 
 
/* perform forward and inverse column mix operation on four bytes in long word x in */ 
/* parallel. NOTE: x must be a simple variable, NOT an expression in these macros.  */ 
 
#if defined(FM4_SET)    /* not currently used */ 
#define fwd_mcol(x)     four_tables(x,t_use(f,m),vf1,rf1,0) 
#elif defined(FM1_SET)  /* not currently used */ 
#define fwd_mcol(x)     one_table(x,upr,t_use(f,m),vf1,rf1,0) 
#else 
#define dec_fmvars      uint_32t g2 
#define fwd_mcol(x)     (g2 = gf_mulx(x), g2 ^ upr((x) ^ g2, 3) ^ upr((x), 2) ^ upr((x), 1)) 
#endif 
 
#if defined(IM4_SET) 
#define inv_mcol(x)     four_tables(x,t_use(i,m),vf1,rf1,0) 
#elif defined(IM1_SET) 
#define inv_mcol(x)     one_table(x,upr,t_use(i,m),vf1,rf1,0) 
#else 
#define dec_imvars      uint_32t g2, g4, g9 
#define inv_mcol(x)     (g2 = gf_mulx(x), g4 = gf_mulx(g2), g9 = (x) ^ gf_mulx(g4), g4 ^= g9, \ 
                        (x) ^ g2 ^ g4 ^ upr(g2 ^ g9, 3) ^ upr(g4, 2) ^ upr(g9, 1)) 
#endif 
 
#if defined(FL4_SET) 
#define ls_box(x,c)     four_tables(x,t_use(f,l),vf1,rf2,c) 
#elif   defined(LS4_SET) 
#define ls_box(x,c)     four_tables(x,t_use(l,s),vf1,rf2,c) 
#elif defined(FL1_SET) 
#define ls_box(x,c)     one_table(x,upr,t_use(f,l),vf1,rf2,c) 
#elif defined(LS1_SET) 
#define ls_box(x,c)     one_table(x,upr,t_use(l,s),vf1,rf2,c) 
#else 
#define ls_box(x,c)     no_table(x,t_use(s,box),vf1,rf2,c) 
#endif 
 
#if defined( ASM_V1 ) && defined( AES_DECRYPT ) && !defined( ISB_SET ) 
#define ISB_SET 
#endif 
 
#endif