crypto/rc5/rc5_enc.c

   1 /*
   2  * Copyright 1995-2016 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 #include <stdio.h>
  11 #include <openssl/rc5.h>
  12 #include "rc5_local.h"
  13
  14 void RC5_32_cbc_encrypt(const unsigned char *in, unsigned char *out,
  15                         long length, RC5_32_KEY *ks, unsigned char *iv,
  16                         int encrypt)
  17 {
  18     register unsigned long tin0, tin1;
  19     register unsigned long tout0, tout1, xor0, xor1;
  20     register long l = length;
  21     unsigned long tin[2];
  22
  23     if (encrypt) {
  24         c2l(iv, tout0);
  25         c2l(iv, tout1);
  26         iv -= 8;
  27         for (l -= 8; l >= 0; l -= 8) {
  28             c2l(in, tin0);
  29             c2l(in, tin1);
  30             tin0 ^= tout0;
  31             tin1 ^= tout1;
  32             tin[0] = tin0;
  33             tin[1] = tin1;
  34             RC5_32_encrypt(tin, ks);
  35             tout0 = tin[0];
  36             l2c(tout0, out);
  37             tout1 = tin[1];
  38             l2c(tout1, out);
  39         }
  40         if (l != -8) {
  41             c2ln(in, tin0, tin1, l + 8);
  42             tin0 ^= tout0;
  43             tin1 ^= tout1;
  44             tin[0] = tin0;
  45             tin[1] = tin1;
  46             RC5_32_encrypt(tin, ks);
  47             tout0 = tin[0];
  48             l2c(tout0, out);
  49             tout1 = tin[1];
  50             l2c(tout1, out);
  51         }
  52         l2c(tout0, iv);
  53         l2c(tout1, iv);
  54     } else {
  55         c2l(iv, xor0);
  56         c2l(iv, xor1);
  57         iv -= 8;
  58         for (l -= 8; l >= 0; l -= 8) {
  59             c2l(in, tin0);
  60             tin[0] = tin0;
  61             c2l(in, tin1);
  62             tin[1] = tin1;
  63             RC5_32_decrypt(tin, ks);
  64             tout0 = tin[0] ^ xor0;
  65             tout1 = tin[1] ^ xor1;
  66             l2c(tout0, out);
  67             l2c(tout1, out);
  68             xor0 = tin0;
  69             xor1 = tin1;
  70         }
  71         if (l != -8) {
  72             c2l(in, tin0);
  73             tin[0] = tin0;
  74             c2l(in, tin1);
  75             tin[1] = tin1;
  76             RC5_32_decrypt(tin, ks);
  77             tout0 = tin[0] ^ xor0;
  78             tout1 = tin[1] ^ xor1;
  79             l2cn(tout0, tout1, out, l + 8);
  80             xor0 = tin0;
  81             xor1 = tin1;
  82         }
  83         l2c(xor0, iv);
  84         l2c(xor1, iv);
  85     }
  86     tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0;
  87     tin[0] = tin[1] = 0;
  88 }
  89
  90 void RC5_32_encrypt(unsigned long *d, RC5_32_KEY *key)
  91 {
  92     RC5_32_INT a, b, *s;
  93
  94     s = key->data;
  95
  96     a = d[0] + s[0];
  97     b = d[1] + s[1];
  98     E_RC5_32(a, b, s, 2);
  99     E_RC5_32(a, b, s, 4);
 100     E_RC5_32(a, b, s, 6);
 101     E_RC5_32(a, b, s, 8);
 102     E_RC5_32(a, b, s, 10);
 103     E_RC5_32(a, b, s, 12);
 104     E_RC5_32(a, b, s, 14);
 105     E_RC5_32(a, b, s, 16);
 106     if (key->rounds == 12) {
 107         E_RC5_32(a, b, s, 18);
 108         E_RC5_32(a, b, s, 20);
 109         E_RC5_32(a, b, s, 22);
 110         E_RC5_32(a, b, s, 24);
 111     } else if (key->rounds == 16) {
 112         /* Do a full expansion to avoid a jump */
 113         E_RC5_32(a, b, s, 18);
 114         E_RC5_32(a, b, s, 20);
 115         E_RC5_32(a, b, s, 22);
 116         E_RC5_32(a, b, s, 24);
 117         E_RC5_32(a, b, s, 26);
 118         E_RC5_32(a, b, s, 28);
 119         E_RC5_32(a, b, s, 30);
 120         E_RC5_32(a, b, s, 32);
 121     }
 122     d[0] = a;
 123     d[1] = b;
 124 }
 125
 126 void RC5_32_decrypt(unsigned long *d, RC5_32_KEY *key)
 127 {
 128     RC5_32_INT a, b, *s;
 129
 130     s = key->data;
 131
 132     a = d[0];
 133     b = d[1];
 134     if (key->rounds == 16) {
 135         D_RC5_32(a, b, s, 32);
 136         D_RC5_32(a, b, s, 30);
 137         D_RC5_32(a, b, s, 28);
 138         D_RC5_32(a, b, s, 26);
 139         /* Do a full expansion to avoid a jump */
 140         D_RC5_32(a, b, s, 24);
 141         D_RC5_32(a, b, s, 22);
 142         D_RC5_32(a, b, s, 20);
 143         D_RC5_32(a, b, s, 18);
 144     } else if (key->rounds == 12) {
 145         D_RC5_32(a, b, s, 24);
 146         D_RC5_32(a, b, s, 22);
 147         D_RC5_32(a, b, s, 20);
 148         D_RC5_32(a, b, s, 18);
 149     }
 150     D_RC5_32(a, b, s, 16);
 151     D_RC5_32(a, b, s, 14);
 152     D_RC5_32(a, b, s, 12);
 153     D_RC5_32(a, b, s, 10);
 154     D_RC5_32(a, b, s, 8);
 155     D_RC5_32(a, b, s, 6);
 156     D_RC5_32(a, b, s, 4);
 157     D_RC5_32(a, b, s, 2);
 158     d[0] = a - s[0];
 159     d[1] = b - s[1];
 160 }