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/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
* All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* 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 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 acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS 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 AUTHOR OR 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.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.]
*/
/* ====================================================================
* Copyright (c) 1998-2001 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.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com). */
#ifndef OPENSSL_HEADER_CRYPTO_INTERNAL_H
#define OPENSSL_HEADER_CRYPTO_INTERNAL_H
#include <openssl/ex_data.h>
#if defined(__cplusplus)
extern "C" {
#endif
/* st_CRYPTO_EX_DATA_IMPL contains an ex_data implementation. See the comments
* in ex_data.h for details of the behaviour of each of the functions. */
struct st_CRYPTO_EX_DATA_IMPL {
int (*new_class)(void);
void (*cleanup)(void);
int (*get_new_index)(int class_value, long argl, void *argp,
CRYPTO_EX_new *new_func, CRYPTO_EX_dup *dup_func,
CRYPTO_EX_free *free_func);
int (*new_ex_data)(int class_value, void *obj, CRYPTO_EX_DATA *ad);
int (*dup_ex_data)(int class_value, CRYPTO_EX_DATA *to,
const CRYPTO_EX_DATA *from);
void (*free_ex_data)(int class_value, void *obj, CRYPTO_EX_DATA *ad);
};
#if defined(_MSC_VER)
#define OPENSSL_U64(x) x##UI64
#else
#if defined(OPENSSL_64_BIT)
#define OPENSSL_U64(x) x##UL
#else
#define OPENSSL_U64(x) x##ULL
#endif
#endif /* defined(_MSC_VER) */
#if defined(OPENSSL_X86) || defined(OPENSSL_X86_64) || defined(OPENSSL_ARM) || \
defined(OPENSSL_AARCH64)
/* OPENSSL_cpuid_setup initializes OPENSSL_ia32cap_P. */
void OPENSSL_cpuid_setup(void);
#endif
#if !defined(inline)
#define inline __inline
#endif
/* Constant-time utility functions.
*
* The following methods return a bitmask of all ones (0xff...f) for true and 0
* for false. This is useful for choosing a value based on the result of a
* conditional in constant time. For example,
*
* if (a < b) {
* c = a;
* } else {
* c = b;
* }
*
* can be written as
*
* unsigned int lt = constant_time_lt(a, b);
* c = constant_time_select(lt, a, b); */
/* constant_time_msb returns the given value with the MSB copied to all the
* other bits. */
static inline unsigned int constant_time_msb(unsigned int a) {
return (unsigned int)((int)(a) >> (sizeof(int) * 8 - 1));
}
/* constant_time_lt returns 0xff..f if a < b and 0 otherwise. */
static inline unsigned int constant_time_lt(unsigned int a, unsigned int b) {
/* Consider the two cases of the problem:
* msb(a) == msb(b): a < b iff the MSB of a - b is set.
* msb(a) != msb(b): a < b iff the MSB of b is set.
*
* If msb(a) == msb(b) then the following evaluates as:
* msb(a^((a^b)|((a-b)^a))) ==
* msb(a^((a-b) ^ a)) == (because msb(a^b) == 0)
* msb(a^a^(a-b)) == (rearranging)
* msb(a-b) (because ∀x. x^x == 0)
*
* Else, if msb(a) != msb(b) then the following evaluates as:
* msb(a^((a^b)|((a-b)^a))) ==
* msb(a^(𝟙 | ((a-b)^a))) == (because msb(a^b) == 1 and 𝟙
* represents a value s.t. msb(𝟙) = 1)
* msb(a^𝟙) == (because ORing with 1 results in 1)
* msb(b)
*
*
* Here is an SMT-LIB verification of this formula:
*
* (define-fun lt ((a (_ BitVec 32)) (b (_ BitVec 32))) (_ BitVec 32)
* (bvxor a (bvor (bvxor a b) (bvxor (bvsub a b) a)))
* )
*
* (declare-fun a () (_ BitVec 32))
* (declare-fun b () (_ BitVec 32))
*
* (assert (not (= (= #x00000001 (bvlshr (lt a b) #x0000001f)) (bvult a b))))
* (check-sat)
* (get-model)
*/
return constant_time_msb(a^((a^b)|((a-b)^a)));
}
/* constant_time_lt_8 acts like |constant_time_lt| but returns an 8-bit mask. */
static inline uint8_t constant_time_lt_8(unsigned int a, unsigned int b) {
return (uint8_t)(constant_time_lt(a, b));
}
/* constant_time_gt returns 0xff..f if a >= b and 0 otherwise. */
static inline unsigned int constant_time_ge(unsigned int a, unsigned int b) {
return ~constant_time_lt(a, b);
}
/* constant_time_ge_8 acts like |constant_time_ge| but returns an 8-bit mask. */
static inline uint8_t constant_time_ge_8(unsigned int a, unsigned int b) {
return (uint8_t)(constant_time_ge(a, b));
}
/* constant_time_is_zero returns 0xff..f if a == 0 and 0 otherwise. */
static inline unsigned int constant_time_is_zero(unsigned int a) {
/* Here is an SMT-LIB verification of this formula:
*
* (define-fun is_zero ((a (_ BitVec 32))) (_ BitVec 32)
* (bvand (bvnot a) (bvsub a #x00000001))
* )
*
* (declare-fun a () (_ BitVec 32))
*
* (assert (not (= (= #x00000001 (bvlshr (is_zero a) #x0000001f)) (= a #x00000000))))
* (check-sat)
* (get-model)
*/
return constant_time_msb(~a & (a - 1));
}
/* constant_time_is_zero_8 acts like constant_time_is_zero but returns an 8-bit
* mask. */
static inline uint8_t constant_time_is_zero_8(unsigned int a) {
return (uint8_t)(constant_time_is_zero(a));
}
/* constant_time_eq returns 0xff..f if a == b and 0 otherwise. */
static inline unsigned int constant_time_eq(unsigned int a, unsigned int b) {
return constant_time_is_zero(a ^ b);
}
/* constant_time_eq_8 acts like |constant_time_eq| but returns an 8-bit mask. */
static inline uint8_t constant_time_eq_8(unsigned int a, unsigned int b) {
return (uint8_t)(constant_time_eq(a, b));
}
/* constant_time_eq_int acts like |constant_time_eq| but works on int values. */
static inline unsigned int constant_time_eq_int(int a, int b) {
return constant_time_eq((unsigned)(a), (unsigned)(b));
}
/* constant_time_eq_int_8 acts like |constant_time_eq_int| but returns an 8-bit
* mask. */
static inline uint8_t constant_time_eq_int_8(int a, int b) {
return constant_time_eq_8((unsigned)(a), (unsigned)(b));
}
/* constant_time_select returns (mask & a) | (~mask & b). When |mask| is all 1s
* or all 0s (as returned by the methods above), the select methods return
* either |a| (if |mask| is nonzero) or |b| (if |mask| is zero). */
static inline unsigned int constant_time_select(unsigned int mask,
unsigned int a, unsigned int b) {
return (mask & a) | (~mask & b);
}
/* constant_time_select_8 acts like |constant_time_select| but operates on
* 8-bit values. */
static inline uint8_t constant_time_select_8(uint8_t mask, uint8_t a,
uint8_t b) {
return (uint8_t)(constant_time_select(mask, a, b));
}
/* constant_time_select_int acts like |constant_time_select| but operates on
* ints. */
static inline int constant_time_select_int(unsigned int mask, int a, int b) {
return (int)(constant_time_select(mask, (unsigned)(a), (unsigned)(b)));
}
#if defined(__cplusplus)
} /* extern C */
#endif
#endif /* OPENSSL_HEADER_CRYPTO_INTERNAL_H */