diff options
author | Andy Polyakov <appro@openssl.org> | 2011-02-10 21:16:21 +0000 |
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committer | Andy Polyakov <appro@openssl.org> | 2011-02-10 21:16:21 +0000 |
commit | 01be5db64e9060eaa991fd35791438b63482ef14 (patch) | |
tree | f96f7df3702a26c8469d52ab878422bd55ee3f16 /crypto/modes/xts128.c | |
parent | a4113c52b227182627c1a102ff70245d210cb669 (diff) |
xts128.c: initial draft.
Diffstat (limited to 'crypto/modes/xts128.c')
-rw-r--r-- | crypto/modes/xts128.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/crypto/modes/xts128.c b/crypto/modes/xts128.c new file mode 100644 index 0000000000..f3890c8854 --- /dev/null +++ b/crypto/modes/xts128.c @@ -0,0 +1,189 @@ +/* ==================================================================== + * 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> + +typedef struct { + void *key1, *key2; + block128_f block1,block2; +} XTS128_CONTEXT; + +int CRYPTO_xts128_encrypt(const XTS128_CONTEXT *ctx, u64 secno, + 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; + + if (len<16) return -1; + + if (is_endian.little) { + tweak.u[0] = secno; + tweak.u[1] = 0; + } + else { + PUTU32(tweak.c,secno); + PUTU32(tweak.c+4,secno>>32); + tweak.u[1] = 0; + } + + (*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); + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + memcpy(out,scratch.c,16); + inp += 16; + out += 16; + len -= 16; + + if (is_endian.little) { + unsigned int carry,res; + + res = 0x87&(((int)tweak.d[3])>>31); + carry = tweak.u[0]>>63; + tweak.u[0] = (tweak.u[0]<<1)^res; + tweak.u[1] = (tweak.u[1]<<1)|carry; + } + else { + unsigned int carry,c,i; + + for (carry=0,i=0;i<16;++i) { + c = tweak.c[i]; + tweak.c[i] = (c<<1)|carry; + carry = c>>7; + } + tweak.c[0] ^= 0x87&(0-carry); + } + } + if (len) { + unsigned int i; + + 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 = tweak.u[0]>>63; + tweak1.u[0] = (tweak.u[0]<<1)^res; + tweak1.u[1] = (tweak.u[1]<<1)|carry; + } + else { + unsigned int carry,c; + + for (carry=0,i=0;i<16;++i) { + c = tweak.c[i]; + tweak1.c[i] = (c<<1)|carry; + carry = c>>7; + } + tweak1.c[0] ^= 0x87&(0-carry); + } +#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); + scratch.u[0] ^= tweak.u[0]; + scratch.u[1] ^= tweak.u[1]; + memcpy (out,scratch.c,16); + } + } + + return 0; +} |