crypto/des/fcrypt_b.c

   1 /*
   2  * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 /*
  11  * DES low level APIs are deprecated for public use, but still ok for internal
  12  * use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <stdio.h>
  17
  18 #define DES_FCRYPT
  19 #include "des_local.h"
  20 #undef DES_FCRYPT
  21
  22 #undef PERM_OP
  23 #define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
  24         (b)^=(t),\
  25         (a)^=((t)<<(n)))
  26
  27 #undef HPERM_OP
  28 #define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
  29         (a)=(a)^(t)^(t>>(16-(n))))\
  30
  31 void fcrypt_body(DES_LONG *out, DES_key_schedule *ks, DES_LONG Eswap0,
  32                  DES_LONG Eswap1)
  33 {
  34     register DES_LONG l, r, t, u;
  35     register DES_LONG *s;
  36     register int j;
  37     register DES_LONG E0, E1;
  38
  39     l = 0;
  40     r = 0;
  41
  42     s = (DES_LONG *)ks;
  43     E0 = Eswap0;
  44     E1 = Eswap1;
  45
  46     for (j = 0; j < 25; j++) {
  47         D_ENCRYPT(l, r, 0);     /* 1 */
  48         D_ENCRYPT(r, l, 2);     /* 2 */
  49         D_ENCRYPT(l, r, 4);     /* 3 */
  50         D_ENCRYPT(r, l, 6);     /* 4 */
  51         D_ENCRYPT(l, r, 8);     /* 5 */
  52         D_ENCRYPT(r, l, 10);    /* 6 */
  53         D_ENCRYPT(l, r, 12);    /* 7 */
  54         D_ENCRYPT(r, l, 14);    /* 8 */
  55         D_ENCRYPT(l, r, 16);    /* 9 */
  56         D_ENCRYPT(r, l, 18);    /* 10 */
  57         D_ENCRYPT(l, r, 20);    /* 11 */
  58         D_ENCRYPT(r, l, 22);    /* 12 */
  59         D_ENCRYPT(l, r, 24);    /* 13 */
  60         D_ENCRYPT(r, l, 26);    /* 14 */
  61         D_ENCRYPT(l, r, 28);    /* 15 */
  62         D_ENCRYPT(r, l, 30);    /* 16 */
  63         t = l;
  64         l = r;
  65         r = t;
  66     }
  67     l = ROTATE(l, 3) & 0xffffffffL;
  68     r = ROTATE(r, 3) & 0xffffffffL;
  69
  70     PERM_OP(l, r, t,  1, 0x55555555L);
  71     PERM_OP(r, l, t,  8, 0x00ff00ffL);
  72     PERM_OP(l, r, t,  2, 0x33333333L);
  73     PERM_OP(r, l, t, 16, 0x0000ffffL);
  74     PERM_OP(l, r, t,  4, 0x0f0f0f0fL);
  75
  76     out[0] = r;
  77     out[1] = l;
  78 }