1 /* crypto/seed/seed_cbc.c -*- mode:C; c-file-style: "eay" -*- */ 2 /* ==================================================================== 3 * Copyright (c) 1998-2007 The OpenSSL Project. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in 14 * the documentation and/or other materials provided with the 15 * distribution. 16 * 17 * 3. All advertising materials mentioning features or use of this 18 * software must display the following acknowledgment: 19 * "This product includes software developed by the OpenSSL Project 20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 21 * 22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 23 * endorse or promote products derived from this software without 24 * prior written permission. For written permission, please contact 25 * openssl-core@openssl.org. 26 * 27 * 5. Products derived from this software may not be called "OpenSSL" 28 * nor may "OpenSSL" appear in their names without prior written 29 * permission of the OpenSSL Project. 30 * 31 * 6. Redistributions of any form whatsoever must retain the following 32 * acknowledgment: 33 * "This product includes software developed by the OpenSSL Project 34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 35 * 36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 47 * OF THE POSSIBILITY OF SUCH DAMAGE. 48 * ==================================================================== 49 * 50 */ 51 52 #include "seed_locl.h" 53 #include <string.h> 54 55 void SEED_cbc_encrypt(const unsigned char *in, unsigned char *out, 56 size_t len, const SEED_KEY_SCHEDULE *ks, 57 unsigned char ivec[SEED_BLOCK_SIZE], int enc) 58 { 59 size_t n; 60 unsigned char tmp[SEED_BLOCK_SIZE]; 61 const unsigned char *iv = ivec; 62 63 if (enc) 64 { 65 while (len >= SEED_BLOCK_SIZE) 66 { 67 for (n = 0; n < SEED_BLOCK_SIZE; ++n) 68 out[n] = in[n] ^ iv[n]; 69 SEED_encrypt(out, out, ks); 70 iv = out; 71 len -= SEED_BLOCK_SIZE; 72 in += SEED_BLOCK_SIZE; 73 out += SEED_BLOCK_SIZE; 74 } 75 if (len) 76 { 77 for (n = 0; n < len; ++n) 78 out[n] = in[n] ^ iv[n]; 79 for (n = len; n < SEED_BLOCK_SIZE; ++n) 80 out[n] = iv[n]; 81 SEED_encrypt(out, out, ks); 82 iv = out; 83 } 84 memcpy(ivec, iv, SEED_BLOCK_SIZE); 85 } 86 else if (in != out) /* decrypt */ 87 { 88 while (len >= SEED_BLOCK_SIZE) 89 { 90 SEED_decrypt(in, out, ks); 91 for (n = 0; n < SEED_BLOCK_SIZE; ++n) 92 out[n] ^= iv[n]; 93 iv = in; 94 len -= SEED_BLOCK_SIZE; 95 in += SEED_BLOCK_SIZE; 96 out += SEED_BLOCK_SIZE; 97 } 98 if (len) 99 { 100 SEED_decrypt(in, tmp, ks); 101 for (n = 0; n < len; ++n) 102 out[n] = tmp[n] ^ iv[n]; 103 iv = in; 104 } 105 memcpy(ivec, iv, SEED_BLOCK_SIZE); 106 } 107 else /* decrypt, overlap */ 108 { 109 while (len >= SEED_BLOCK_SIZE) 110 { 111 memcpy(tmp, in, SEED_BLOCK_SIZE); 112 SEED_decrypt(in, out, ks); 113 for (n = 0; n < SEED_BLOCK_SIZE; ++n) 114 out[n] ^= ivec[n]; 115 memcpy(ivec, tmp, SEED_BLOCK_SIZE); 116 len -= SEED_BLOCK_SIZE; 117 in += SEED_BLOCK_SIZE; 118 out += SEED_BLOCK_SIZE; 119 } 120 if (len) 121 { 122 memcpy(tmp, in, SEED_BLOCK_SIZE); 123 SEED_decrypt(tmp, tmp, ks); 124 for (n = 0; n < len; ++n) 125 out[n] = tmp[n] ^ ivec[n]; 126 memcpy(ivec, tmp, SEED_BLOCK_SIZE); 127 } 128 } 129 } 130