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 * CAST low level APIs are deprecated for public use, but still ok for 12 * internal use. 13 */ 14 #include "internal/deprecated.h" 15 16 #include <openssl/cast.h> 17 #include "cast_local.h" 18 19 void CAST_encrypt(CAST_LONG *data, const CAST_KEY *key) 20 { 21 CAST_LONG l, r, t; 22 const CAST_LONG *k; 23 24 k = &(key->data[0]); 25 l = data[0]; 26 r = data[1]; 27 28 E_CAST(0, k, l, r, +, ^, -); 29 E_CAST(1, k, r, l, ^, -, +); 30 E_CAST(2, k, l, r, -, +, ^); 31 E_CAST(3, k, r, l, +, ^, -); 32 E_CAST(4, k, l, r, ^, -, +); 33 E_CAST(5, k, r, l, -, +, ^); 34 E_CAST(6, k, l, r, +, ^, -); 35 E_CAST(7, k, r, l, ^, -, +); 36 E_CAST(8, k, l, r, -, +, ^); 37 E_CAST(9, k, r, l, +, ^, -); 38 E_CAST(10, k, l, r, ^, -, +); 39 E_CAST(11, k, r, l, -, +, ^); 40 if (!key->short_key) { 41 E_CAST(12, k, l, r, +, ^, -); 42 E_CAST(13, k, r, l, ^, -, +); 43 E_CAST(14, k, l, r, -, +, ^); 44 E_CAST(15, k, r, l, +, ^, -); 45 } 46 47 data[1] = l & 0xffffffffL; 48 data[0] = r & 0xffffffffL; 49 } 50 51 void CAST_decrypt(CAST_LONG *data, const CAST_KEY *key) 52 { 53 CAST_LONG l, r, t; 54 const CAST_LONG *k; 55 56 k = &(key->data[0]); 57 l = data[0]; 58 r = data[1]; 59 60 if (!key->short_key) { 61 E_CAST(15, k, l, r, +, ^, -); 62 E_CAST(14, k, r, l, -, +, ^); 63 E_CAST(13, k, l, r, ^, -, +); 64 E_CAST(12, k, r, l, +, ^, -); 65 } 66 E_CAST(11, k, l, r, -, +, ^); 67 E_CAST(10, k, r, l, ^, -, +); 68 E_CAST(9, k, l, r, +, ^, -); 69 E_CAST(8, k, r, l, -, +, ^); 70 E_CAST(7, k, l, r, ^, -, +); 71 E_CAST(6, k, r, l, +, ^, -); 72 E_CAST(5, k, l, r, -, +, ^); 73 E_CAST(4, k, r, l, ^, -, +); 74 E_CAST(3, k, l, r, +, ^, -); 75 E_CAST(2, k, r, l, -, +, ^); 76 E_CAST(1, k, l, r, ^, -, +); 77 E_CAST(0, k, r, l, +, ^, -); 78 79 data[1] = l & 0xffffffffL; 80 data[0] = r & 0xffffffffL; 81 } 82 83 void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out, 84 long length, const CAST_KEY *ks, unsigned char *iv, 85 int enc) 86 { 87 register CAST_LONG tin0, tin1; 88 register CAST_LONG tout0, tout1, xor0, xor1; 89 register long l = length; 90 CAST_LONG tin[2]; 91 92 if (enc) { 93 n2l(iv, tout0); 94 n2l(iv, tout1); 95 iv -= 8; 96 for (l -= 8; l >= 0; l -= 8) { 97 n2l(in, tin0); 98 n2l(in, tin1); 99 tin0 ^= tout0; 100 tin1 ^= tout1; 101 tin[0] = tin0; 102 tin[1] = tin1; 103 CAST_encrypt(tin, ks); 104 tout0 = tin[0]; 105 tout1 = tin[1]; 106 l2n(tout0, out); 107 l2n(tout1, out); 108 } 109 if (l != -8) { 110 n2ln(in, tin0, tin1, l + 8); 111 tin0 ^= tout0; 112 tin1 ^= tout1; 113 tin[0] = tin0; 114 tin[1] = tin1; 115 CAST_encrypt(tin, ks); 116 tout0 = tin[0]; 117 tout1 = tin[1]; 118 l2n(tout0, out); 119 l2n(tout1, out); 120 } 121 l2n(tout0, iv); 122 l2n(tout1, iv); 123 } else { 124 n2l(iv, xor0); 125 n2l(iv, xor1); 126 iv -= 8; 127 for (l -= 8; l >= 0; l -= 8) { 128 n2l(in, tin0); 129 n2l(in, tin1); 130 tin[0] = tin0; 131 tin[1] = tin1; 132 CAST_decrypt(tin, ks); 133 tout0 = tin[0] ^ xor0; 134 tout1 = tin[1] ^ xor1; 135 l2n(tout0, out); 136 l2n(tout1, out); 137 xor0 = tin0; 138 xor1 = tin1; 139 } 140 if (l != -8) { 141 n2l(in, tin0); 142 n2l(in, tin1); 143 tin[0] = tin0; 144 tin[1] = tin1; 145 CAST_decrypt(tin, ks); 146 tout0 = tin[0] ^ xor0; 147 tout1 = tin[1] ^ xor1; 148 l2nn(tout0, tout1, out, l + 8); 149 xor0 = tin0; 150 xor1 = tin1; 151 } 152 l2n(xor0, iv); 153 l2n(xor1, iv); 154 } 155 tin0 = tin1 = tout0 = tout1 = xor0 = xor1 = 0; 156 tin[0] = tin[1] = 0; 157 } 158