418 lines
19 KiB
C
418 lines
19 KiB
C
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/* Copyright (C) 1995-1997 Eric Young (eay@cryptsoft.com)
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* All rights reserved.
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*
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* This package is an SSL implementation written
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* by Eric Young (eay@cryptsoft.com).
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* The implementation was written so as to conform with Netscapes SSL.
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*
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* This library is free for commercial and non-commercial use as long as
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* the following conditions are aheared to. The following conditions
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* apply to all code found in this distribution, be it the RC4, RSA,
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* lhash, DES, etc., code; not just the SSL code. The SSL documentation
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* included with this distribution is covered by the same copyright terms
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* except that the holder is Tim Hudson (tjh@cryptsoft.com).
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*
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* Copyright remains Eric Young's, and as such any Copyright notices in
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* the code are not to be removed.
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* If this package is used in a product, Eric Young should be given attribution
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* as the author of the parts of the library used.
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* This can be in the form of a textual message at program startup or
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* in documentation (online or textual) provided with the package.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* "This product includes cryptographic software written by
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* Eric Young (eay@cryptsoft.com)"
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* The word 'cryptographic' can be left out if the rouines from the library
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* being used are not cryptographic related :-).
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* 4. If you include any Windows specific code (or a derivative thereof) from
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* the apps directory (application code) you must include an acknowledgement:
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* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
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*
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* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* The licence and distribution terms for any publically available version or
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* derivative of this code cannot be changed. i.e. this code cannot simply be
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* copied and put under another distribution licence
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* [including the GNU Public Licence.]
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*/
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/* ====================================================================
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* Copyright (c) 1998-2006 The OpenSSL Project. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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*
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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*
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* 3. All advertising materials mentioning features or use of this
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* software must display the following acknowledgment:
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* "This product includes software developed by the OpenSSL Project
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* for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
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*
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* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
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* endorse or promote products derived from this software without
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* prior written permission. For written permission, please contact
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* openssl-core@openssl.org.
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*
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* 5. Products derived from this software may not be called "OpenSSL"
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* nor may "OpenSSL" appear in their names without prior written
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* permission of the OpenSSL Project.
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*
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* 6. Redistributions of any form whatsoever must retain the following
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* acknowledgment:
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* "This product includes software developed by the OpenSSL Project
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* for use in the OpenSSL Toolkit (http://www.openssl.org/)"
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*
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* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
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* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
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* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
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* OF THE POSSIBILITY OF SUCH DAMAGE.
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* ====================================================================
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*
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* This product includes cryptographic software written by Eric Young
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* (eay@cryptsoft.com). This product includes software written by Tim
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* Hudson (tjh@cryptsoft.com).
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*
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*/
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/* ====================================================================
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* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
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*
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* Portions of the attached software ("Contribution") are developed by
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* SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
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*
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* The Contribution is licensed pursuant to the Eric Young open source
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* license provided above.
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*
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* The binary polynomial arithmetic software is originally written by
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* Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems
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* Laboratories. */
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#ifndef OPENSSL_HEADER_BN_INTERNAL_H
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#define OPENSSL_HEADER_BN_INTERNAL_H
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#include <openssl/base.h>
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#if defined(OPENSSL_X86_64) && defined(_MSC_VER)
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OPENSSL_MSVC_PRAGMA(warning(push, 3))
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#include <intrin.h>
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OPENSSL_MSVC_PRAGMA(warning(pop))
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#pragma intrinsic(__umulh, _umul128)
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#endif
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#include "../../internal.h"
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#if defined(__cplusplus)
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extern "C" {
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#endif
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#if defined(OPENSSL_64_BIT)
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#if defined(BORINGSSL_HAS_UINT128)
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// MSVC doesn't support two-word integers on 64-bit.
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#define BN_ULLONG uint128_t
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#if defined(BORINGSSL_CAN_DIVIDE_UINT128)
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#define BN_CAN_DIVIDE_ULLONG
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#endif
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#endif
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#define BN_BITS2 64
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#define BN_BYTES 8
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#define BN_BITS4 32
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#define BN_MASK2 (0xffffffffffffffffUL)
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#define BN_MASK2l (0xffffffffUL)
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#define BN_MASK2h (0xffffffff00000000UL)
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#define BN_MASK2h1 (0xffffffff80000000UL)
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#define BN_MONT_CTX_N0_LIMBS 1
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#define BN_DEC_CONV (10000000000000000000UL)
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#define BN_DEC_NUM 19
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#define TOBN(hi, lo) ((BN_ULONG)(hi) << 32 | (lo))
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#elif defined(OPENSSL_32_BIT)
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#define BN_ULLONG uint64_t
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#define BN_CAN_DIVIDE_ULLONG
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#define BN_BITS2 32
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#define BN_BYTES 4
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#define BN_BITS4 16
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#define BN_MASK2 (0xffffffffUL)
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#define BN_MASK2l (0xffffUL)
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#define BN_MASK2h1 (0xffff8000UL)
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#define BN_MASK2h (0xffff0000UL)
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// On some 32-bit platforms, Montgomery multiplication is done using 64-bit
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// arithmetic with SIMD instructions. On such platforms, |BN_MONT_CTX::n0|
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// needs to be two words long. Only certain 32-bit platforms actually make use
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// of n0[1] and shorter R value would suffice for the others. However,
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// currently only the assembly files know which is which.
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#define BN_MONT_CTX_N0_LIMBS 2
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#define BN_DEC_CONV (1000000000UL)
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#define BN_DEC_NUM 9
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#define TOBN(hi, lo) (lo), (hi)
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#else
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#error "Must define either OPENSSL_32_BIT or OPENSSL_64_BIT"
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#endif
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#define STATIC_BIGNUM(x) \
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{ \
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(BN_ULONG *)(x), sizeof(x) / sizeof(BN_ULONG), \
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sizeof(x) / sizeof(BN_ULONG), 0, BN_FLG_STATIC_DATA \
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}
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#if defined(BN_ULLONG)
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#define Lw(t) ((BN_ULONG)(t))
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#define Hw(t) ((BN_ULONG)((t) >> BN_BITS2))
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#endif
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// bn_correct_top decrements |bn->top| until |bn->d[top-1]| is non-zero or
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// until |top| is zero. If |bn| is zero, |bn->neg| is set to zero.
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void bn_correct_top(BIGNUM *bn);
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// bn_wexpand ensures that |bn| has at least |words| works of space without
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// altering its value. It returns one on success or zero on allocation
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// failure.
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int bn_wexpand(BIGNUM *bn, size_t words);
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// bn_expand acts the same as |bn_wexpand|, but takes a number of bits rather
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// than a number of words.
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int bn_expand(BIGNUM *bn, size_t bits);
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// bn_set_words sets |bn| to the value encoded in the |num| words in |words|,
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// least significant word first.
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int bn_set_words(BIGNUM *bn, const BN_ULONG *words, size_t num);
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// bn_mul_add_words multiples |ap| by |w|, adds the result to |rp|, and places
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// the result in |rp|. |ap| and |rp| must both be |num| words long. It returns
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// the carry word of the operation. |ap| and |rp| may be equal but otherwise may
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// not alias.
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BN_ULONG bn_mul_add_words(BN_ULONG *rp, const BN_ULONG *ap, size_t num,
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BN_ULONG w);
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// bn_mul_words multiples |ap| by |w| and places the result in |rp|. |ap| and
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// |rp| must both be |num| words long. It returns the carry word of the
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// operation. |ap| and |rp| may be equal but otherwise may not alias.
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BN_ULONG bn_mul_words(BN_ULONG *rp, const BN_ULONG *ap, size_t num, BN_ULONG w);
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// bn_sqr_words sets |rp[2*i]| and |rp[2*i+1]| to |ap[i]|'s square, for all |i|
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// up to |num|. |ap| is an array of |num| words and |rp| an array of |2*num|
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// words. |ap| and |rp| may not alias.
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//
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// This gives the contribution of the |ap[i]*ap[i]| terms when squaring |ap|.
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void bn_sqr_words(BN_ULONG *rp, const BN_ULONG *ap, size_t num);
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// bn_add_words adds |ap| to |bp| and places the result in |rp|, each of which
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// are |num| words long. It returns the carry bit, which is one if the operation
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// overflowed and zero otherwise. Any pair of |ap|, |bp|, and |rp| may be equal
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// to each other but otherwise may not alias.
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BN_ULONG bn_add_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,
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size_t num);
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// bn_sub_words subtracts |bp| from |ap| and places the result in |rp|. It
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// returns the borrow bit, which is one if the computation underflowed and zero
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// otherwise. Any pair of |ap|, |bp|, and |rp| may be equal to each other but
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// otherwise may not alias.
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BN_ULONG bn_sub_words(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,
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size_t num);
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// bn_mul_comba4 sets |r| to the product of |a| and |b|.
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void bn_mul_comba4(BN_ULONG r[8], const BN_ULONG a[4], const BN_ULONG b[4]);
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// bn_mul_comba8 sets |r| to the product of |a| and |b|.
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void bn_mul_comba8(BN_ULONG r[16], const BN_ULONG a[8], const BN_ULONG b[8]);
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// bn_sqr_comba8 sets |r| to |a|^2.
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void bn_sqr_comba8(BN_ULONG r[16], const BN_ULONG a[4]);
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// bn_sqr_comba4 sets |r| to |a|^2.
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void bn_sqr_comba4(BN_ULONG r[8], const BN_ULONG a[4]);
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// bn_cmp_words returns a value less than, equal to or greater than zero if
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// the, length |n|, array |a| is less than, equal to or greater than |b|.
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int bn_cmp_words(const BN_ULONG *a, const BN_ULONG *b, int n);
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// bn_cmp_words returns a value less than, equal to or greater than zero if the
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// array |a| is less than, equal to or greater than |b|. The arrays can be of
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// different lengths: |cl| gives the minimum of the two lengths and |dl| gives
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// the length of |a| minus the length of |b|.
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int bn_cmp_part_words(const BN_ULONG *a, const BN_ULONG *b, int cl, int dl);
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// bn_less_than_words returns one if |a| < |b| and zero otherwise, where |a|
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// and |b| both are |len| words long. It runs in constant time.
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int bn_less_than_words(const BN_ULONG *a, const BN_ULONG *b, size_t len);
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// bn_in_range_words returns one if |min_inclusive| <= |a| < |max_exclusive|,
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// where |a| and |max_exclusive| both are |len| words long. This function leaks
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// which of [0, min_inclusive), [min_inclusive, max_exclusive), and
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// [max_exclusive, 2^(BN_BITS2*len)) contains |a|, but otherwise the value of
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// |a| is secret.
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int bn_in_range_words(const BN_ULONG *a, BN_ULONG min_inclusive,
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const BN_ULONG *max_exclusive, size_t len);
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// bn_rand_range_words sets |out| to a uniformly distributed random number from
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// |min_inclusive| to |max_exclusive|. Both |out| and |max_exclusive| are |len|
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// words long.
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//
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// This function runs in time independent of the result, but |min_inclusive| and
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// |max_exclusive| are public data. (Information about the range is unavoidably
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// leaked by how many iterations it took to select a number.)
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int bn_rand_range_words(BN_ULONG *out, BN_ULONG min_inclusive,
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const BN_ULONG *max_exclusive, size_t len,
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const uint8_t additional_data[32]);
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int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,
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const BN_ULONG *np, const BN_ULONG *n0, int num);
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uint64_t bn_mont_n0(const BIGNUM *n);
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int bn_mod_exp_base_2_vartime(BIGNUM *r, unsigned p, const BIGNUM *n);
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#if defined(OPENSSL_X86_64) && defined(_MSC_VER)
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#define BN_UMULT_LOHI(low, high, a, b) ((low) = _umul128((a), (b), &(high)))
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#endif
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#if !defined(BN_ULLONG) && !defined(BN_UMULT_LOHI)
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#error "Either BN_ULLONG or BN_UMULT_LOHI must be defined on every platform."
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#endif
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// bn_mod_inverse_prime sets |out| to the modular inverse of |a| modulo |p|,
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// computed with Fermat's Little Theorem. It returns one on success and zero on
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// error. If |mont_p| is NULL, one will be computed temporarily.
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int bn_mod_inverse_prime(BIGNUM *out, const BIGNUM *a, const BIGNUM *p,
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BN_CTX *ctx, const BN_MONT_CTX *mont_p);
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// bn_mod_inverse_secret_prime behaves like |bn_mod_inverse_prime| but uses
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// |BN_mod_exp_mont_consttime| instead of |BN_mod_exp_mont| in hopes of
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// protecting the exponent.
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int bn_mod_inverse_secret_prime(BIGNUM *out, const BIGNUM *a, const BIGNUM *p,
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BN_CTX *ctx, const BN_MONT_CTX *mont_p);
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// bn_jacobi returns the Jacobi symbol of |a| and |b| (which is -1, 0 or 1), or
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// -2 on error.
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int bn_jacobi(const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx);
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// bn_is_bit_set_words returns one if bit |bit| is set in |a| and zero
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// otherwise.
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int bn_is_bit_set_words(const BN_ULONG *a, size_t num, unsigned bit);
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// Low-level operations for small numbers.
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//
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// The following functions implement algorithms suitable for use with scalars
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// and field elements in elliptic curves. They rely on the number being small
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// both to stack-allocate various temporaries and because they do not implement
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// optimizations useful for the larger values used in RSA.
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// BN_SMALL_MAX_WORDS is the largest size input these functions handle. This
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// limit allows temporaries to be more easily stack-allocated. This limit is set
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// to accommodate P-521.
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#if defined(OPENSSL_32_BIT)
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#define BN_SMALL_MAX_WORDS 17
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#else
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#define BN_SMALL_MAX_WORDS 9
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#endif
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// bn_mul_small sets |r| to |a|*|b|. |num_r| must be |num_a| + |num_b|. |r| may
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// not alias with |a| or |b|. This function returns one on success and zero if
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// lengths are inconsistent.
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int bn_mul_small(BN_ULONG *r, size_t num_r, const BN_ULONG *a, size_t num_a,
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const BN_ULONG *b, size_t num_b);
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// bn_sqr_small sets |r| to |a|^2. |num_a| must be at most |BN_SMALL_MAX_WORDS|.
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// |num_r| must be |num_a|*2. |r| and |a| may not alias. This function returns
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// one on success and zero on programmer error.
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int bn_sqr_small(BN_ULONG *r, size_t num_r, const BN_ULONG *a, size_t num_a);
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// In the following functions, the modulus must be at most |BN_SMALL_MAX_WORDS|
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// words long.
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// bn_to_montgomery_small sets |r| to |a| translated to the Montgomery domain.
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// |num_a| and |num_r| must be the length of the modulus, which is
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// |mont->N.top|. |a| must be fully reduced. This function returns one on
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// success and zero if lengths are inconsistent. |r| and |a| may alias.
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int bn_to_montgomery_small(BN_ULONG *r, size_t num_r, const BN_ULONG *a,
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size_t num_a, const BN_MONT_CTX *mont);
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// bn_from_montgomery_small sets |r| to |a| translated out of the Montgomery
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// domain. |num_r| must be the length of the modulus, which is |mont->N.top|.
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// |a| must be at most |mont->N.top| * R and |num_a| must be at most 2 *
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// |mont->N.top|. This function returns one on success and zero if lengths are
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// inconsistent. |r| and |a| may alias.
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int bn_from_montgomery_small(BN_ULONG *r, size_t num_r, const BN_ULONG *a,
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size_t num_a, const BN_MONT_CTX *mont);
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// bn_mod_mul_montgomery_small sets |r| to |a| * |b| mod |mont->N|. Both inputs
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// and outputs are in the Montgomery domain. |num_r| must be the length of the
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// modulus, which is |mont->N.top|. This function returns one on success and
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// zero on internal error or inconsistent lengths. Any two of |r|, |a|, and |b|
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// may alias.
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//
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// This function requires |a| * |b| < N * R, where N is the modulus and R is the
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// Montgomery divisor, 2^(N.top * BN_BITS2). This should generally be satisfied
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// by ensuring |a| and |b| are fully reduced, however ECDSA has one computation
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// which requires the more general bound.
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int bn_mod_mul_montgomery_small(BN_ULONG *r, size_t num_r, const BN_ULONG *a,
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size_t num_a, const BN_ULONG *b, size_t num_b,
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const BN_MONT_CTX *mont);
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// bn_mod_exp_mont_small sets |r| to |a|^|p| mod |mont->N|. It returns one on
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// success and zero on programmer or internal error. Both inputs and outputs are
|
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// in the Montgomery domain. |num_r| and |num_a| must be |mont->N.top|, which
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// must be at most |BN_SMALL_MAX_WORDS|. |a| must be fully-reduced. This
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// function runs in time independent of |a|, but |p| and |mont->N| are public
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// values.
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//
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// Note this function differs from |BN_mod_exp_mont| which uses Montgomery
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// reduction but takes input and output outside the Montgomery domain. Combine
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// this function with |bn_from_montgomery_small| and |bn_to_montgomery_small|
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// if necessary.
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int bn_mod_exp_mont_small(BN_ULONG *r, size_t num_r, const BN_ULONG *a,
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size_t num_a, const BN_ULONG *p, size_t num_p,
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|
const BN_MONT_CTX *mont);
|
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|
// bn_mod_inverse_prime_mont_small sets |r| to |a|^-1 mod |mont->N|. |mont->N|
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// must be a prime. |num_r| and |num_a| must be |mont->N.top|, which must be at
|
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|
// most |BN_SMALL_MAX_WORDS|. |a| must be fully-reduced. This function runs in
|
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|
// time independent of |a|, but |mont->N| is a public value.
|
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|
int bn_mod_inverse_prime_mont_small(BN_ULONG *r, size_t num_r,
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|
const BN_ULONG *a, size_t num_a,
|
||
|
const BN_MONT_CTX *mont);
|
||
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|
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|
#if defined(__cplusplus)
|
||
|
} // extern C
|
||
|
#endif
|
||
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|
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|
#endif // OPENSSL_HEADER_BN_INTERNAL_H
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