1 /* ==================================================================== 2 * Copyright (c) 2008 The OpenSSL Project. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in 13 * the documentation and/or other materials provided with the 14 * distribution. 15 * 16 * 3. All advertising materials mentioning features or use of this 17 * software must display the following acknowledgment: 18 * "This product includes software developed by the OpenSSL Project 19 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 20 * 21 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 22 * endorse or promote products derived from this software without 23 * prior written permission. For written permission, please contact 24 * openssl-core (at) openssl.org. 25 * 26 * 5. Products derived from this software may not be called "OpenSSL" 27 * nor may "OpenSSL" appear in their names without prior written 28 * permission of the OpenSSL Project. 29 * 30 * 6. Redistributions of any form whatsoever must retain the following 31 * acknowledgment: 32 * "This product includes software developed by the OpenSSL Project 33 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 34 * 35 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 36 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 38 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 39 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 40 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 41 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 42 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 44 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 45 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 46 * OF THE POSSIBILITY OF SUCH DAMAGE. 47 * ==================================================================== */ 48 49 #include <openssl/modes.h> 50 51 #include <assert.h> 52 53 #include "internal.h" 54 55 56 void CRYPTO_ofb128_encrypt(const uint8_t *in, uint8_t *out, size_t len, 57 const void *key, uint8_t ivec[16], int *num, 58 block128_f block) { 59 unsigned int n; 60 size_t l=0; 61 62 assert(in && out && key && ivec && num); 63 assert((16 % sizeof(size_t)) == 0); 64 65 n = *num; 66 67 while (n && len) { 68 *(out++) = *(in++) ^ ivec[n]; 69 --len; 70 n = (n + 1) % 16; 71 } 72 73 if (STRICT_ALIGNMENT && 74 ((size_t)in | (size_t)out | (size_t)ivec) % sizeof(size_t) != 0) { 75 while (l < len) { 76 if (n == 0) { 77 (*block)(ivec, ivec, key); 78 } 79 out[l] = in[l] ^ ivec[n]; 80 ++l; 81 n = (n + 1) % 16; 82 } 83 84 *num = n; 85 return; 86 } 87 88 while (len >= 16) { 89 (*block)(ivec, ivec, key); 90 for (; n < 16; n += sizeof(size_t)) { 91 *(size_t *)(out + n) = *(size_t *)(in + n) ^ *(size_t *)(ivec + n); 92 } 93 len -= 16; 94 out += 16; 95 in += 16; 96 n = 0; 97 } 98 if (len) { 99 (*block)(ivec, ivec, key); 100 while (len--) { 101 out[n] = in[n] ^ ivec[n]; 102 ++n; 103 } 104 } 105 *num = n; 106 } 107
