aesopt.h

aes算法的加密解密

#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 USER CONFIGURED OPTIONS ---- */

/* VIA ACE support is only available for VC++ and GCC */

#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

/* Assembler support requires the use of platform byte order */

#if ( defined( ASM_X86_V1C ) || defined( ASM_X86_V2C ) || defined( ASM_AMD64_C ) ) \
    && (ALGORITHM_BYTE_ORDER != PLATFORM_BYTE_ORDER)
#  undef  ALGORITHM_BYTE_ORDER
#  define ALGORITHM_BYTE_ORDER PLATFORM_BYTE_ORDER
#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

/*  This implementation provides subroutines for encryption, decryption
    and for setting the three key lengths (separately) for encryption
    and decryption. Since not all functions are needed, masks are set
    up here to determine which will be implemented in C
*/

#if !defined( AES_ENCRYPT )
#  define EFUNCS_IN_C   0
#elif defined( ASSUME_VIA_ACE_PRESENT ) || defined( ASM_X86_V1C ) \
    || defined( ASM_X86_V2C ) || defined( ASM_AMD64_C )
#  define EFUNCS_IN_C   ENC_KEYING_IN_C
#elif !defined( ASM_X86_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( ASSUME_VIA_ACE_PRESENT ) || defined( ASM_X86_V1C ) \
    || defined( ASM_X86_V2C ) || defined( ASM_AMD64_C )
#  define DFUNCS_IN_C   DEC_KEYING_IN_C
#elif !defined( ASM_X86_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 )

/* 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)     to_byte((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)     to_byte((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_X86_V1C )
#  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 ) || defined( ASM_X86_V1C )
#  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 ) || defined( ASM_X86_V1C )
#  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 !(defined( REDUCE_CODE_SIZE ) && (defined( ASM_X86_V2 ) || defined( ASM_X86_V2C )))
#  if ((FUNCS_IN_C & ENC_KEYING_IN_C) || (FUNCS_IN_C & DEC_KEYING_IN_C))
#    if KEY_SCHED == ONE_TABLE
#      if !defined( FL1_SET )  && !defined( FL4_SET ) 
#        define LS1_SET
#      endif
#    elif KEY_SCHED == FOUR_TABLES
#      if !defined( FL4_SET )
#        define LS4_SET
#      endif
#    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
#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( REDUCE_CODE_SIZE ) && (defined( ASM_X86_V2 ) || defined( ASM_X86_V2C ))) 

#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

#endif

#if defined( ASM_X86_V1C ) && defined( AES_DECRYPT ) && !defined( ISB_SET )
#  define ISB_SET
#endif

#endif