1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/netwerk/srtp/src/crypto/include/gf2_8.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,79 @@
1.4 +/*
1.5 + * gf2_8.h
1.6 + *
1.7 + * GF(256) implementation
1.8 + *
1.9 + * David A. McGrew
1.10 + * Cisco Systems, Inc.
1.11 + */
1.12 +
1.13 +/*
1.14 + *
1.15 + * Copyright (c) 2001-2006, Cisco Systems, Inc.
1.16 + * All rights reserved.
1.17 + *
1.18 + * Redistribution and use in source and binary forms, with or without
1.19 + * modification, are permitted provided that the following conditions
1.20 + * are met:
1.21 + *
1.22 + * Redistributions of source code must retain the above copyright
1.23 + * notice, this list of conditions and the following disclaimer.
1.24 + *
1.25 + * Redistributions in binary form must reproduce the above
1.26 + * copyright notice, this list of conditions and the following
1.27 + * disclaimer in the documentation and/or other materials provided
1.28 + * with the distribution.
1.29 + *
1.30 + * Neither the name of the Cisco Systems, Inc. nor the names of its
1.31 + * contributors may be used to endorse or promote products derived
1.32 + * from this software without specific prior written permission.
1.33 + *
1.34 + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.35 + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.36 + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
1.37 + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
1.38 + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
1.39 + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
1.40 + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
1.41 + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
1.42 + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
1.43 + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.44 + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
1.45 + * OF THE POSSIBILITY OF SUCH DAMAGE.
1.46 + *
1.47 + */
1.48 +
1.49 +
1.50 +#ifndef GF2_8_H
1.51 +#define GF2_8_H
1.52 +
1.53 +#include "datatypes.h" /* for uint8_t definition */
1.54 +
1.55 +typedef uint8_t gf2_8;
1.56 +
1.57 +#define gf2_8_field_polynomial 0x1B
1.58 +
1.59 +/*
1.60 + * gf2_8_shift(x) returns
1.61 + */
1.62 +
1.63 +/*
1.64 + * gf2_8_shift(z) returns the result of the GF(2^8) 'multiply by x'
1.65 + * operation, using the field representation from AES; that is, the
1.66 + * next gf2_8 value in the cyclic representation of that field. The
1.67 + * value z should be an uint8_t.
1.68 + */
1.69 +
1.70 +#define gf2_8_shift(z) (((z) & 128) ? \
1.71 + (((z) << 1) ^ gf2_8_field_polynomial) : ((z) << 1))
1.72 +
1.73 +gf2_8
1.74 +gf2_8_compute_inverse(gf2_8 x);
1.75 +
1.76 +void
1.77 +test_gf2_8(void);
1.78 +
1.79 +gf2_8
1.80 +gf2_8_multiply(gf2_8 x, gf2_8 y);
1.81 +
1.82 +#endif /* GF2_8_H */
