/* 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 #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(OPENSSL_WINDOWS) #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 /* OPENSSL_WINDOWS */ #if defined(OPENSSL_X86) || defined(OPENSSL_X86_64) /* 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 */