1 /* 2 * Copyright 2014-2021 The OpenSSL Project Authors. All Rights Reserved. 3 * 4 * Licensed under the Apache License 2.0 (the "License"). You may not use 5 * this file except in compliance with the License. You can obtain a copy 6 * in the file LICENSE in the source distribution or at 7 * https://www.openssl.org/source/license.html 8 */ 9 10 #ifndef OSSL_CRYPTO_BN_H 11 # define OSSL_CRYPTO_BN_H 12 # pragma once 13 14 # include <openssl/bn.h> 15 # include <limits.h> 16 17 BIGNUM *bn_wexpand(BIGNUM *a, int words); 18 BIGNUM *bn_expand2(BIGNUM *a, int words); 19 20 void bn_correct_top(BIGNUM *a); 21 22 /* 23 * Determine the modified width-(w+1) Non-Adjacent Form (wNAF) of 'scalar'. 24 * This is an array r[] of values that are either zero or odd with an 25 * absolute value less than 2^w satisfying scalar = \sum_j r[j]*2^j where at 26 * most one of any w+1 consecutive digits is non-zero with the exception that 27 * the most significant digit may be only w-1 zeros away from that next 28 * non-zero digit. 29 */ 30 signed char *bn_compute_wNAF(const BIGNUM *scalar, int w, size_t *ret_len); 31 32 int bn_get_top(const BIGNUM *a); 33 34 int bn_get_dmax(const BIGNUM *a); 35 36 /* Set all words to zero */ 37 void bn_set_all_zero(BIGNUM *a); 38 39 /* 40 * Copy the internal BIGNUM words into out which holds size elements (and size 41 * must be bigger than top) 42 */ 43 int bn_copy_words(BN_ULONG *out, const BIGNUM *in, int size); 44 45 BN_ULONG *bn_get_words(const BIGNUM *a); 46 47 /* 48 * Set the internal data words in a to point to words which contains size 49 * elements. The BN_FLG_STATIC_DATA flag is set 50 */ 51 void bn_set_static_words(BIGNUM *a, const BN_ULONG *words, int size); 52 53 /* 54 * Copy words into the BIGNUM |a|, reallocating space as necessary. 55 * The negative flag of |a| is not modified. 56 * Returns 1 on success and 0 on failure. 57 */ 58 /* 59 * |num_words| is int because bn_expand2 takes an int. This is an internal 60 * function so we simply trust callers not to pass negative values. 61 */ 62 int bn_set_words(BIGNUM *a, const BN_ULONG *words, int num_words); 63 64 /* 65 * Some BIGNUM functions assume most significant limb to be non-zero, which 66 * is customarily arranged by bn_correct_top. Output from below functions 67 * is not processed with bn_correct_top, and for this reason it may not be 68 * returned out of public API. It may only be passed internally into other 69 * functions known to support non-minimal or zero-padded BIGNUMs. Even 70 * though the goal is to facilitate constant-time-ness, not each subroutine 71 * is constant-time by itself. They all have pre-conditions, consult source 72 * code... 73 */ 74 int bn_mul_mont_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 75 BN_MONT_CTX *mont, BN_CTX *ctx); 76 int bn_to_mont_fixed_top(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont, 77 BN_CTX *ctx); 78 int bn_from_mont_fixed_top(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont, 79 BN_CTX *ctx); 80 int bn_mod_add_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 81 const BIGNUM *m); 82 int bn_mod_sub_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, 83 const BIGNUM *m); 84 int bn_mul_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx); 85 int bn_sqr_fixed_top(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx); 86 int bn_lshift_fixed_top(BIGNUM *r, const BIGNUM *a, int n); 87 int bn_rshift_fixed_top(BIGNUM *r, const BIGNUM *a, int n); 88 int bn_div_fixed_top(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, 89 const BIGNUM *d, BN_CTX *ctx); 90 91 #define BN_PRIMETEST_COMPOSITE 0 92 #define BN_PRIMETEST_COMPOSITE_WITH_FACTOR 1 93 #define BN_PRIMETEST_COMPOSITE_NOT_POWER_OF_PRIME 2 94 #define BN_PRIMETEST_PROBABLY_PRIME 3 95 96 int ossl_bn_miller_rabin_is_prime(const BIGNUM *w, int iterations, BN_CTX *ctx, 97 BN_GENCB *cb, int enhanced, int *status); 98 99 const BIGNUM *ossl_bn_get0_small_factors(void); 100 101 int ossl_bn_rsa_fips186_4_gen_prob_primes(BIGNUM *p, BIGNUM *Xpout, 102 BIGNUM *p1, BIGNUM *p2, 103 const BIGNUM *Xp, const BIGNUM *Xp1, 104 const BIGNUM *Xp2, int nlen, 105 const BIGNUM *e, BN_CTX *ctx, 106 BN_GENCB *cb); 107 108 int ossl_bn_rsa_fips186_4_derive_prime(BIGNUM *Y, BIGNUM *X, const BIGNUM *Xin, 109 const BIGNUM *r1, const BIGNUM *r2, 110 int nlen, const BIGNUM *e, BN_CTX *ctx, 111 BN_GENCB *cb); 112 113 OSSL_LIB_CTX *ossl_bn_get_libctx(BN_CTX *ctx); 114 115 extern const BIGNUM ossl_bn_inv_sqrt_2; 116 117 int ossl_bn_rsa_do_unblind(const BIGNUM *intermediate, 118 const BN_BLINDING *blinding, 119 const BIGNUM *possible_arg2, 120 const BIGNUM *to_mod, BN_CTX *ctx, 121 unsigned char *buf, int num); 122 123 #endif 124