diff options
Diffstat (limited to 'openssl-1.1.0h/crypto/modes/xts128.c')
| -rw-r--r-- | openssl-1.1.0h/crypto/modes/xts128.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/modes/xts128.c b/openssl-1.1.0h/crypto/modes/xts128.c new file mode 100644 index 0000000..81b1eac --- /dev/null +++ b/openssl-1.1.0h/crypto/modes/xts128.c @@ -0,0 +1,157 @@ +/* + * Copyright 2011-2016 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the OpenSSL license (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html + */ + +#include <openssl/crypto.h> +#include "modes_lcl.h" +#include <string.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; +} |