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Diffstat (limited to 'crypto/modes/ofb128.c')
| -rw-r--r-- | crypto/modes/ofb128.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/crypto/modes/ofb128.c b/crypto/modes/ofb128.c new file mode 100644 index 0000000000..09b3430034 --- /dev/null +++ b/crypto/modes/ofb128.c @@ -0,0 +1,128 @@ +/* ==================================================================== + * Copyright (c) 2008 The OpenSSL Project. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * + * 3. All advertising materials mentioning features or use of this + * software must display the following acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" + * + * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to + * endorse or promote products derived from this software without + * prior written permission. For written permission, please contact + * openssl-core@openssl.org. + * + * 5. Products derived from this software may not be called "OpenSSL" + * nor may "OpenSSL" appear in their names without prior written + * permission of the OpenSSL Project. + * + * 6. Redistributions of any form whatsoever must retain the following + * acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit (http://www.openssl.org/)" + * + * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY + * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR + * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * ==================================================================== + * + */ + +#include "modes.h" +#include <string.h> + +#ifndef MODES_DEBUG +# ifndef NDEBUG +# define NDEBUG +# endif +#endif +#include <assert.h> + +#define STRICT_ALIGNMENT +#if defined(__i386) || defined(__i386__) || \ + defined(__x86_64) || defined(__x86_64__) || \ + defined(_M_IX86) || defined(_M_AMD64) || defined(_M_X64) || \ + defined(__s390__) || defined(__s390x__) +# undef STRICT_ALIGNMENT +#endif + +/* The input and output encrypted as though 128bit ofb mode is being + * used. The extra state information to record how much of the + * 128bit block we have used is contained in *num; + */ +void CRYPTO_ofb128_encrypt(const unsigned char *in, unsigned char *out, + size_t len, const void *key, + unsigned char ivec[16], int *num, + block128_f block) +{ + unsigned int n; + size_t l=0; + + assert(in && out && key && ivec && num); + + n = *num; + +#if !defined(OPENSSL_SMALL_FOOTPRINT) + if (16%sizeof(size_t) == 0) do { /* always true actually */ + while (n && len) { + *(out++) = *(in++) ^ ivec[n]; + --len; + n = (n+1) % 16; + } +#if defined(STRICT_ALIGNMENT) + if (((size_t)in|(size_t)out|(size_t)ivec)%sizeof(size_t) != 0) + break; +#endif + while (len>=16) { + (*block)(ivec, ivec, key); + for (n=0; n<16; n+=sizeof(size_t)) + *(size_t*)(out+n) = + *(size_t*)(in+n) ^ *(size_t*)(ivec+n); + len -= 16; + out += 16; + in += 16; + } + n = 0; + if (len) { + (*block)(ivec, ivec, key); + while (len--) { + out[n] = in[n] ^ ivec[n]; + ++n; + } + } + *num = n; + return; + } while(0); + /* the rest would be commonly eliminated by x86* compiler */ +#endif + while (l<len) { + if (n==0) { + (*block)(ivec, ivec, key); + } + out[l] = in[l] ^ ivec[n]; + ++l; + n = (n+1) % 16; + } + + *num=n; +} |