1 /* 2 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the OpenSSL license (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 <openssl/cast.h> 11 #include "cast_local.h" 12 13 void CAST_encrypt(CAST_LONG *data, const CAST_KEY *key) 14 { 15 CAST_LONG l, r, t; 16 const CAST_LONG *k; 17 18 k = &(key->data[0]); 19 l = data[0]; 20 r = data[1]; 21 22 E_CAST(0, k, l, r, +, ^, -); 23 E_CAST(1, k, r, l, ^, -, +); 24 E_CAST(2, k, l, r, -, +, ^); 25 E_CAST(3, k, r, l, +, ^, -); 26 E_CAST(4, k, l, r, ^, -, +); 27 E_CAST(5, k, r, l, -, +, ^); 28 E_CAST(6, k, l, r, +, ^, -); 29 E_CAST(7, k, r, l, ^, -, +); 30 E_CAST(8, k, l, r, -, +, ^); 31 E_CAST(9, k, r, l, +, ^, -); 32 E_CAST(10, k, l, r, ^, -, +); 33 E_CAST(11, k, r, l, -, +, ^); 34 if (!key->short_key) { 35 E_CAST(12, k, l, r, +, ^, -); 36 E_CAST(13, k, r, l, ^, -, +); 37 E_CAST(14, k, l, r, -, +, ^); 38 E_CAST(15, k, r, l, +, ^, -); 39 } 40 41 data[1] = l & 0xffffffffL; 42 data[0] = r & 0xffffffffL; 43 } 44 45 void CAST_decrypt(CAST_LONG *data, const CAST_KEY *key) 46 { 47 CAST_LONG l, r, t; 48 const CAST_LONG *k; 49 50 k = &(key->data[0]); 51 l = data[0]; 52 r = data[1]; 53 54 if (!key->short_key) { 55 E_CAST(15, k, l, r, +, ^, -); 56 E_CAST(14, k, r, l, -, +, ^); 57 E_CAST(13, k, l, r, ^, -, +); 58 E_CAST(12, k, r, l, +, ^, -); 59 } 60 E_CAST(11, k, l, r, -, +, ^); 61 E_CAST(10, k, r, l, ^, -, +); 62 E_CAST(9, k, l, r, +, ^, -); 63 E_CAST(8, k, r, l, -, +, ^); 64 E_CAST(7, k, l, r, ^, -, +); 65 E_CAST(6, k, r, l, +, ^, -); 66 E_CAST(5, k, l, r, -, +, ^); 67 E_CAST(4, k, r, l, ^, -, +); 68 E_CAST(3, k, l, r, +, ^, -); 69 E_CAST(2, k, r, l, -, +, ^); 70 E_CAST(1, k, l, r, ^, -, +); 71 E_CAST(0, k, r, l, +, ^, -); 72 73 data[1] = l & 0xffffffffL; 74 data[0] = r & 0xffffffffL; 75 } 76 77 void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out, 78 long length, const CAST_KEY *ks, unsigned char *iv, 79 int enc) 80 { 81 register CAST_LONG tin0, tin1; 82 register CAST_LONG tout0, tout1, xor0, xor1; 83 register long l = length; 84 CAST_LONG tin[2]; 85 86 if (enc) { 87 n2l(iv, tout0); 88 n2l(iv, tout1); 89 iv -= 8; 90 for (l -= 8; l >= 0; l -= 8) { 91 n2l(in, tin0); 92 n2l(in, tin1); 93 tin0 ^= tout0; 94 tin1 ^= tout1; 95 tin[0] = tin0; 96 tin[1] = tin1; 97 CAST_encrypt(tin, ks); 98 tout0 = tin[0]; 99 tout1 = tin[1]; 100 l2n(tout0, out); 101 l2n(tout1, out); 102 } 103 if (l != -8) { 104 n2ln(in, tin0, tin1, l + 8); 105 tin0 ^= tout0; 106 tin1 ^= tout1; 107 tin[0] = tin0; 108 tin[1] = tin1; 109 CAST_encrypt(tin, ks); 110 tout0 = tin[0]; 111 tout1 = tin[1]; 112 l2n(tout0, out); 113 l2n(tout1, out); 114 } 115 l2n(tout0, iv); 116 l2n(tout1, iv); 117 } else { 118 n2l(iv, xor0); 119 n2l(iv, xor1); 120 iv -= 8; 121 for (l -= 8; l >= 0; l -= 8) { 122 n2l(in, tin0); 123 n2l(in, tin1); 124 tin[0] = tin0; 125 tin[1] = tin1; 126 CAST_decrypt(tin, ks); 127 tout0 = tin[0] ^ xor0; 128 tout1 = tin[1] ^ xor1; 129 l2n(tout0, out); 130 l2n(tout1, out); 131 xor0 = tin0; 132 xor1 = tin1; 133 } 134 if (l != -8) { 135 n2l(in, tin0); 136 n2l(in, tin1); 137 tin[0] = tin0; 138 tin[1] = tin1; 139 CAST_decrypt(tin, ks); 140 tout0 = tin[0] ^ xor0; 141 tout1 = tin[1] ^ xor1; 142 l2nn(tout0, tout1, out, l + 8); 143 xor0 = tin0; 144 xor1 = tin1; 145 } 146 l2n(xor0, iv); 147 l2n(xor1, iv); 148 } 149 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0; 150 tin[0] = tin[1] = 0; 151 } 152