/* $OpenBSD: aes_ige.c,v 1.5 2014/06/12 15:49:27 deraadt Exp $ */ /* ==================================================================== * Copyright (c) 2006 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 #include #include "aes_locl.h" #define N_WORDS (AES_BLOCK_SIZE / sizeof(unsigned long)) typedef struct { unsigned long data[N_WORDS]; } aes_block_t; /* XXX: probably some better way to do this */ #if defined(__i386__) || defined(__x86_64__) #define UNALIGNED_MEMOPS_ARE_FAST 1 #else #define UNALIGNED_MEMOPS_ARE_FAST 0 #endif #if UNALIGNED_MEMOPS_ARE_FAST #define load_block(d, s) (d) = *(const aes_block_t *)(s) #define store_block(d, s) *(aes_block_t *)(d) = (s) #else #define load_block(d, s) memcpy((d).data, (s), AES_BLOCK_SIZE) #define store_block(d, s) memcpy((d), (s).data, AES_BLOCK_SIZE) #endif /* N.B. The IV for this mode is _twice_ the block size */ void AES_ige_encrypt(const unsigned char *in, unsigned char *out, size_t length, const AES_KEY *key, unsigned char *ivec, const int enc) { size_t n; size_t len = length; OPENSSL_assert(in && out && key && ivec); OPENSSL_assert((AES_ENCRYPT == enc) || (AES_DECRYPT == enc)); OPENSSL_assert((length % AES_BLOCK_SIZE) == 0); len = length / AES_BLOCK_SIZE; if (AES_ENCRYPT == enc) { if (in != out && (UNALIGNED_MEMOPS_ARE_FAST || ((size_t)in|(size_t)out|(size_t)ivec) % sizeof(long) == 0)) { aes_block_t *ivp = (aes_block_t *)ivec; aes_block_t *iv2p = (aes_block_t *)(ivec + AES_BLOCK_SIZE); while (len) { aes_block_t *inp = (aes_block_t *)in; aes_block_t *outp = (aes_block_t *)out; for (n = 0; n < N_WORDS; ++n) outp->data[n] = inp->data[n] ^ ivp->data[n]; AES_encrypt((unsigned char *)outp->data, (unsigned char *)outp->data, key); for (n = 0; n < N_WORDS; ++n) outp->data[n] ^= iv2p->data[n]; ivp = outp; iv2p = inp; --len; in += AES_BLOCK_SIZE; out += AES_BLOCK_SIZE; } memcpy(ivec, ivp->data, AES_BLOCK_SIZE); memcpy(ivec + AES_BLOCK_SIZE, iv2p->data, AES_BLOCK_SIZE); } else { aes_block_t tmp, tmp2; aes_block_t iv; aes_block_t iv2; load_block(iv, ivec); load_block(iv2, ivec + AES_BLOCK_SIZE); while (len) { load_block(tmp, in); for (n = 0; n < N_WORDS; ++n) tmp2.data[n] = tmp.data[n] ^ iv.data[n]; AES_encrypt((unsigned char *)tmp2.data, (unsigned char *)tmp2.data, key); for (n = 0; n < N_WORDS; ++n) tmp2.data[n] ^= iv2.data[n]; store_block(out, tmp2); iv = tmp2; iv2 = tmp; --len; in += AES_BLOCK_SIZE; out += AES_BLOCK_SIZE; } memcpy(ivec, iv.data, AES_BLOCK_SIZE); memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE); } } else { if (in != out && (UNALIGNED_MEMOPS_ARE_FAST || ((size_t)in|(size_t)out|(size_t)ivec) % sizeof(long) == 0)) { aes_block_t *ivp = (aes_block_t *)ivec; aes_block_t *iv2p = (aes_block_t *)(ivec + AES_BLOCK_SIZE); while (len) { aes_block_t tmp; aes_block_t *inp = (aes_block_t *)in; aes_block_t *outp = (aes_block_t *)out; for (n = 0; n < N_WORDS; ++n) tmp.data[n] = inp->data[n] ^ iv2p->data[n]; AES_decrypt((unsigned char *)tmp.data, (unsigned char *)outp->data, key); for (n = 0; n < N_WORDS; ++n) outp->data[n] ^= ivp->data[n]; ivp = inp; iv2p = outp; --len; in += AES_BLOCK_SIZE; out += AES_BLOCK_SIZE; } memcpy(ivec, ivp->data, AES_BLOCK_SIZE); memcpy(ivec + AES_BLOCK_SIZE, iv2p->data, AES_BLOCK_SIZE); } else { aes_block_t tmp, tmp2; aes_block_t iv; aes_block_t iv2; load_block(iv, ivec); load_block(iv2, ivec + AES_BLOCK_SIZE); while (len) { load_block(tmp, in); tmp2 = tmp; for (n = 0; n < N_WORDS; ++n) tmp.data[n] ^= iv2.data[n]; AES_decrypt((unsigned char *)tmp.data, (unsigned char *)tmp.data, key); for (n = 0; n < N_WORDS; ++n) tmp.data[n] ^= iv.data[n]; store_block(out, tmp); iv = tmp2; iv2 = tmp; --len; in += AES_BLOCK_SIZE; out += AES_BLOCK_SIZE; } memcpy(ivec, iv.data, AES_BLOCK_SIZE); memcpy(ivec + AES_BLOCK_SIZE, iv2.data, AES_BLOCK_SIZE); } } }