crypto/external/bsd/heimdal/dist/lib/hcrypto/rc2.c

   1 /*      $NetBSD: rc2.c,v 1.1.1.2 2014/04/24 12:45:30 pettai Exp $       */
   2
   3 /*
   4  * Copyright (c) 2004 Kungliga Tekniska Högskolan
   5  * (Royal Institute of Technology, Stockholm, Sweden).
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <config.h>
  37
  38 #include "rc2.h"
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42
  43 /*
  44  * Implemented from Peter Gutmann's "Specification for Ron Rivests Cipher No.2"
  45  * rfc2268 and "On the Design and Security of RC2" was also useful.
  46  */
  47
  48 static unsigned int Sbox[256] = {
  49     0xd9, 0x78, 0xf9, 0xc4, 0x19, 0xdd, 0xb5, 0xed,
  50     0x28, 0xe9, 0xfd, 0x79, 0x4a, 0xa0, 0xd8, 0x9d,
  51     0xc6, 0x7e, 0x37, 0x83, 0x2b, 0x76, 0x53, 0x8e,
  52     0x62, 0x4c, 0x64, 0x88, 0x44, 0x8b, 0xfb, 0xa2,
  53     0x17, 0x9a, 0x59, 0xf5, 0x87, 0xb3, 0x4f, 0x13,
  54     0x61, 0x45, 0x6d, 0x8d, 0x09, 0x81, 0x7d, 0x32,
  55     0xbd, 0x8f, 0x40, 0xeb, 0x86, 0xb7, 0x7b, 0x0b,
  56     0xf0, 0x95, 0x21, 0x22, 0x5c, 0x6b, 0x4e, 0x82,
  57     0x54, 0xd6, 0x65, 0x93, 0xce, 0x60, 0xb2, 0x1c,
  58     0x73, 0x56, 0xc0, 0x14, 0xa7, 0x8c, 0xf1, 0xdc,
  59     0x12, 0x75, 0xca, 0x1f, 0x3b, 0xbe, 0xe4, 0xd1,
  60     0x42, 0x3d, 0xd4, 0x30, 0xa3, 0x3c, 0xb6, 0x26,
  61     0x6f, 0xbf, 0x0e, 0xda, 0x46, 0x69, 0x07, 0x57,
  62     0x27, 0xf2, 0x1d, 0x9b, 0xbc, 0x94, 0x43, 0x03,
  63     0xf8, 0x11, 0xc7, 0xf6, 0x90, 0xef, 0x3e, 0xe7,
  64     0x06, 0xc3, 0xd5, 0x2f, 0xc8, 0x66, 0x1e, 0xd7,
  65     0x08, 0xe8, 0xea, 0xde, 0x80, 0x52, 0xee, 0xf7,
  66     0x84, 0xaa, 0x72, 0xac, 0x35, 0x4d, 0x6a, 0x2a,
  67     0x96, 0x1a, 0xd2, 0x71, 0x5a, 0x15, 0x49, 0x74,
  68     0x4b, 0x9f, 0xd0, 0x5e, 0x04, 0x18, 0xa4, 0xec,
  69     0xc2, 0xe0, 0x41, 0x6e, 0x0f, 0x51, 0xcb, 0xcc,
  70     0x24, 0x91, 0xaf, 0x50, 0xa1, 0xf4, 0x70, 0x39,
  71     0x99, 0x7c, 0x3a, 0x85, 0x23, 0xb8, 0xb4, 0x7a,
  72     0xfc, 0x02, 0x36, 0x5b, 0x25, 0x55, 0x97, 0x31,
  73     0x2d, 0x5d, 0xfa, 0x98, 0xe3, 0x8a, 0x92, 0xae,
  74     0x05, 0xdf, 0x29, 0x10, 0x67, 0x6c, 0xba, 0xc9,
  75     0xd3, 0x00, 0xe6, 0xcf, 0xe1, 0x9e, 0xa8, 0x2c,
  76     0x63, 0x16, 0x01, 0x3f, 0x58, 0xe2, 0x89, 0xa9,
  77     0x0d, 0x38, 0x34, 0x1b, 0xab, 0x33, 0xff, 0xb0,
  78     0xbb, 0x48, 0x0c, 0x5f, 0xb9, 0xb1, 0xcd, 0x2e,
  79     0xc5, 0xf3, 0xdb, 0x47, 0xe5, 0xa5, 0x9c, 0x77,
  80     0x0a, 0xa6, 0x20, 0x68, 0xfe, 0x7f, 0xc1, 0xad
  81 };
  82
  83 void
  84 RC2_set_key(RC2_KEY *key, int len, const unsigned char *data, int bits)
  85 {
  86     unsigned char k[128];
  87     int j, T8, TM;
  88
  89     if (len <= 0)
  90         abort();
  91     if (len > 128)
  92         len = 128;
  93     if (bits <= 0 || bits > 1024)
  94         bits = 1024;
  95
  96     for (j = 0; j < len; j++)
  97         k[j] = data[j];
  98     for (; j < 128; j++)
  99         k[j] = Sbox[(k[j - len] + k[j - 1]) & 0xff];
 100
 101     T8 = (bits + 7) / 8;
 102     j = (8*T8 - bits);
 103     TM = 0xff >> j;
 104
 105     k[128 - T8] = Sbox[k[128 - T8] & TM];
 106
 107     for (j = 127 - T8; j >= 0; j--)
 108         k[j] = Sbox[k[j + 1] ^ k[j + T8]];
 109
 110     for (j = 0; j < 64; j++)
 111         key->data[j] = k[(j * 2) + 0] | (k[(j * 2) + 1] << 8);
 112     memset(k, 0, sizeof(k));
 113 }
 114
 115 #define ROT16L(w,n)  ((w<<n)|(w>>(16-n)))
 116 #define ROT16R(w,n)  ((w>>n)|(w<<(16-n)))
 117
 118 void
 119 RC2_encryptc(unsigned char *in, unsigned char *out, const RC2_KEY *key)
 120 {
 121     int i, j;
 122     int w0, w1, w2, w3;
 123     int t0, t1, t2, t3;
 124
 125     w0 = in[0] | (in[1] << 8);
 126     w1 = in[2] | (in[3] << 8);
 127     w2 = in[4] | (in[5] << 8);
 128     w3 = in[6] | (in[7] << 8);
 129
 130     for (i = 0; i < 16; i++) {
 131         j = i * 4;
 132         t0 = (w0 + (w1 & ~w3) + (w2 & w3) + key->data[j + 0]) & 0xffff;
 133         w0 = ROT16L(t0, 1);
 134         t1 = (w1 + (w2 & ~w0) + (w3 & w0) + key->data[j + 1]) & 0xffff;
 135         w1 = ROT16L(t1, 2);
 136         t2 = (w2 + (w3 & ~w1) + (w0 & w1) + key->data[j + 2]) & 0xffff;
 137         w2 = ROT16L(t2, 3);
 138         t3 = (w3 + (w0 & ~w2) + (w1 & w2) + key->data[j + 3]) & 0xffff;
 139         w3 = ROT16L(t3, 5);
 140         if(i == 4 || i == 10) {
 141             w0 += key->data[w3 & 63];
 142             w1 += key->data[w0 & 63];
 143             w2 += key->data[w1 & 63];
 144             w3 += key->data[w2 & 63];
 145         }
 146     }
 147
 148     out[0] = w0 & 0xff;
 149     out[1] = (w0 >> 8) & 0xff;
 150     out[2] = w1 & 0xff;
 151     out[3] = (w1 >> 8) & 0xff;
 152     out[4] = w2 & 0xff;
 153     out[5] = (w2 >> 8) & 0xff;
 154     out[6] = w3 & 0xff;
 155     out[7] = (w3 >> 8) & 0xff;
 156 }
 157
 158 void
 159 RC2_decryptc(unsigned char *in, unsigned char *out, const RC2_KEY *key)
 160 {
 161     int i, j;
 162     int w0, w1, w2, w3;
 163     int t0, t1, t2, t3;
 164
 165     w0 = in[0] | (in[1] << 8);
 166     w1 = in[2] | (in[3] << 8);
 167     w2 = in[4] | (in[5] << 8);
 168     w3 = in[6] | (in[7] << 8);
 169
 170     for (i = 15; i >= 0; i--) {
 171         j = i * 4;
 172
 173         if(i == 4 || i == 10) {
 174             w3 = (w3 - key->data[w2 & 63]) & 0xffff;
 175             w2 = (w2 - key->data[w1 & 63]) & 0xffff;
 176             w1 = (w1 - key->data[w0 & 63]) & 0xffff;
 177             w0 = (w0 - key->data[w3 & 63]) & 0xffff;
 178         }
 179
 180         t3 = ROT16R(w3, 5);
 181         w3 = (t3 - (w0 & ~w2) - (w1 & w2) - key->data[j + 3]) & 0xffff;
 182         t2 = ROT16R(w2, 3);
 183         w2 = (t2 - (w3 & ~w1) - (w0 & w1) - key->data[j + 2]) & 0xffff;
 184         t1 = ROT16R(w1, 2);
 185         w1 = (t1 - (w2 & ~w0) - (w3 & w0) - key->data[j + 1]) & 0xffff;
 186         t0 = ROT16R(w0, 1);
 187         w0 = (t0 - (w1 & ~w3) - (w2 & w3) - key->data[j + 0]) & 0xffff;
 188
 189     }
 190     out[0] = w0 & 0xff;
 191     out[1] = (w0 >> 8) & 0xff;
 192     out[2] = w1 & 0xff;
 193     out[3] = (w1 >> 8) & 0xff;
 194     out[4] = w2 & 0xff;
 195     out[5] = (w2 >> 8) & 0xff;
 196     out[6] = w3 & 0xff;
 197     out[7] = (w3 >> 8) & 0xff;
 198 }
 199
 200 void
 201 RC2_cbc_encrypt(const unsigned char *in, unsigned char *out, long size,
 202                 RC2_KEY *key, unsigned char *iv, int forward_encrypt)
 203 {
 204     unsigned char tmp[RC2_BLOCK_SIZE];
 205     int i;
 206
 207     if (forward_encrypt) {
 208         while (size >= RC2_BLOCK_SIZE) {
 209             for (i = 0; i < RC2_BLOCK_SIZE; i++)
 210                 tmp[i] = in[i] ^ iv[i];
 211             RC2_encryptc(tmp, out, key);
 212             memcpy(iv, out, RC2_BLOCK_SIZE);
 213             size -= RC2_BLOCK_SIZE;
 214             in += RC2_BLOCK_SIZE;
 215             out += RC2_BLOCK_SIZE;
 216         }
 217         if (size) {
 218             for (i = 0; i < size; i++)
 219                 tmp[i] = in[i] ^ iv[i];
 220             for (i = size; i < RC2_BLOCK_SIZE; i++)
 221                 tmp[i] = iv[i];
 222             RC2_encryptc(tmp, out, key);
 223             memcpy(iv, out, RC2_BLOCK_SIZE);
 224         }
 225     } else {
 226         while (size >= RC2_BLOCK_SIZE) {
 227             memcpy(tmp, in, RC2_BLOCK_SIZE);
 228             RC2_decryptc(tmp, out, key);
 229             for (i = 0; i < RC2_BLOCK_SIZE; i++)
 230                 out[i] ^= iv[i];
 231             memcpy(iv, tmp, RC2_BLOCK_SIZE);
 232             size -= RC2_BLOCK_SIZE;
 233             in += RC2_BLOCK_SIZE;
 234             out += RC2_BLOCK_SIZE;
 235         }
 236         if (size) {
 237             memcpy(tmp, in, RC2_BLOCK_SIZE);
 238             RC2_decryptc(tmp, out, key);
 239             for (i = 0; i < size; i++)
 240                 out[i] ^= iv[i];
 241             memcpy(iv, tmp, RC2_BLOCK_SIZE);
 242         }
 243     }
 244 }