2 * Copyright 2014-2021 The OpenSSL Project Authors. All Rights Reserved.
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
10 #ifndef OSSL_CRYPTO_BN_H
11 # define OSSL_CRYPTO_BN_H
14 # include <openssl/bn.h>
17 BIGNUM *bn_wexpand(BIGNUM *a, int words);
18 BIGNUM *bn_expand2(BIGNUM *a, int words);
20 void bn_correct_top(BIGNUM *a);
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
30 signed char *bn_compute_wNAF(const BIGNUM *scalar, int w, size_t *ret_len);
32 int bn_get_top(const BIGNUM *a);
34 int bn_get_dmax(const BIGNUM *a);
36 /* Set all words to zero */
37 void bn_set_all_zero(BIGNUM *a);
40 * Copy the internal BIGNUM words into out which holds size elements (and size
41 * must be bigger than top)
43 int bn_copy_words(BN_ULONG *out, const BIGNUM *in, int size);
45 BN_ULONG *bn_get_words(const BIGNUM *a);
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
51 void bn_set_static_words(BIGNUM *a, const BN_ULONG *words, int size);
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.
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.
62 int bn_set_words(BIGNUM *a, const BN_ULONG *words, int num_words);
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
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,
78 int bn_from_mont_fixed_top(BIGNUM *r, const BIGNUM *a, BN_MONT_CTX *mont,
80 int bn_mod_add_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
82 int bn_mod_sub_fixed_top(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
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);
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
96 int ossl_bn_miller_rabin_is_prime(const BIGNUM *w, int iterations, BN_CTX *ctx,
97 BN_GENCB *cb, int enhanced, int *status);
99 const BIGNUM *ossl_bn_get0_small_factors(void);
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,
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,
113 OSSL_LIB_CTX *ossl_bn_get_libctx(BN_CTX *ctx);
115 extern const BIGNUM ossl_bn_inv_sqrt_2;
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);