diff options
Diffstat (limited to 'openssl/crypto/modes/xts128.c')
| -rw-r--r-- | openssl/crypto/modes/xts128.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/openssl/crypto/modes/xts128.c b/openssl/crypto/modes/xts128.c new file mode 100644 index 000000000..9cf27a25e --- /dev/null +++ b/openssl/crypto/modes/xts128.c @@ -0,0 +1,187 @@ +/* ==================================================================== + * Copyright (c) 2011 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 <openssl/crypto.h> +#include "modes_lcl.h" +#include <string.h> + +#ifndef MODES_DEBUG +# ifndef NDEBUG +# define NDEBUG +# endif +#endif +#include <assert.h> + +int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, const unsigned char iv[16], + const unsigned char *inp, unsigned char *out, + size_t len, int enc) +{ + const union { long one; char little; } is_endian = {1}; + union { u64 u[2]; u32 d[4]; u8 c[16]; } tweak, scratch; + unsigned int i; + + if (len<16) return -1; + + memcpy(tweak.c, iv, 16); + + (*ctx->block2)(tweak.c,tweak.c,ctx->key2); + + if (!enc && (len%16)) len-=16; + + while (len>=16) { +#if defined(STRICT_ALIGNMENT) + memcpy(scratch.c,inp,16); + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; +#else + scratch.u[0] = ((u64*)inp)[0]^tweak.u[0]; + scratch.u[1] = ((u64*)inp)[1]^tweak.u[1]; +#endif + (*ctx->block1)(scratch.c,scratch.c,ctx->key1); +#if defined(STRICT_ALIGNMENT) + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + memcpy(out,scratch.c,16); +#else + ((u64*)out)[0] = scratch.u[0]^=tweak.u[0]; + ((u64*)out)[1] = scratch.u[1]^=tweak.u[1]; +#endif + inp += 16; + out += 16; + len -= 16; + + if (len==0) return 0; + + if (is_endian.little) { + unsigned int carry,res; + + res = 0x87&(((int)tweak.d[3])>>31); + carry = (unsigned int)(tweak.u[0]>>63); + tweak.u[0] = (tweak.u[0]<<1)^res; + tweak.u[1] = (tweak.u[1]<<1)|carry; + } + else { + size_t c; + + for (c=0,i=0;i<16;++i) { + /*+ substitutes for |, because c is 1 bit */ + c += ((size_t)tweak.c[i])<<1; + tweak.c[i] = (u8)c; + c = c>>8; + } + tweak.c[0] ^= (u8)(0x87&(0-c)); + } + } + if (enc) { + for (i=0;i<len;++i) { + u8 c = inp[i]; + out[i] = scratch.c[i]; + scratch.c[i] = c; + } + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + (*ctx->block1)(scratch.c,scratch.c,ctx->key1); + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + memcpy(out-16,scratch.c,16); + } + else { + union { u64 u[2]; u8 c[16]; } tweak1; + + if (is_endian.little) { + unsigned int carry,res; + + res = 0x87&(((int)tweak.d[3])>>31); + carry = (unsigned int)(tweak.u[0]>>63); + tweak1.u[0] = (tweak.u[0]<<1)^res; + tweak1.u[1] = (tweak.u[1]<<1)|carry; + } + else { + size_t c; + + for (c=0,i=0;i<16;++i) { + /*+ substitutes for |, because c is 1 bit */ + c += ((size_t)tweak.c[i])<<1; + tweak1.c[i] = (u8)c; + c = c>>8; + } + tweak1.c[0] ^= (u8)(0x87&(0-c)); + } +#if defined(STRICT_ALIGNMENT) + memcpy(scratch.c,inp,16); + scratch.u[0] ^= tweak1.u[0]; + scratch.u[1] ^= tweak1.u[1]; +#else + scratch.u[0] = ((u64*)inp)[0]^tweak1.u[0]; + scratch.u[1] = ((u64*)inp)[1]^tweak1.u[1]; +#endif + (*ctx->block1)(scratch.c,scratch.c,ctx->key1); + scratch.u[0] ^= tweak1.u[0]; + scratch.u[1] ^= tweak1.u[1]; + + for (i=0;i<len;++i) { + u8 c = inp[16+i]; + out[16+i] = scratch.c[i]; + scratch.c[i] = c; + } + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + (*ctx->block1)(scratch.c,scratch.c,ctx->key1); +#if defined(STRICT_ALIGNMENT) + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + memcpy (out,scratch.c,16); +#else + ((u64*)out)[0] = scratch.u[0]^tweak.u[0]; + ((u64*)out)[1] = scratch.u[1]^tweak.u[1]; +#endif + } + + return 0; +} |