diff options
Diffstat (limited to 'openssl-1.1.0h/crypto/bn/bn_x931p.c')
| -rw-r--r-- | openssl-1.1.0h/crypto/bn/bn_x931p.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/openssl-1.1.0h/crypto/bn/bn_x931p.c b/openssl-1.1.0h/crypto/bn/bn_x931p.c new file mode 100644 index 0000000..8bfbcac --- /dev/null +++ b/openssl-1.1.0h/crypto/bn/bn_x931p.c @@ -0,0 +1,242 @@ +/* + * Copyright 2011-2016 The OpenSSL Project Authors. All Rights Reserved. + * + * Licensed under the OpenSSL license (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html + */ + +#include <stdio.h> +#include <openssl/bn.h> +#include "bn_lcl.h" + +/* X9.31 routines for prime derivation */ + +/* + * X9.31 prime derivation. This is used to generate the primes pi (p1, p2, + * q1, q2) from a parameter Xpi by checking successive odd integers. + */ + +static int bn_x931_derive_pi(BIGNUM *pi, const BIGNUM *Xpi, BN_CTX *ctx, + BN_GENCB *cb) +{ + int i = 0, is_prime; + if (!BN_copy(pi, Xpi)) + return 0; + if (!BN_is_odd(pi) && !BN_add_word(pi, 1)) + return 0; + for (;;) { + i++; + BN_GENCB_call(cb, 0, i); + /* NB 27 MR is specified in X9.31 */ + is_prime = BN_is_prime_fasttest_ex(pi, 27, ctx, 1, cb); + if (is_prime < 0) + return 0; + if (is_prime) + break; + if (!BN_add_word(pi, 2)) + return 0; + } + BN_GENCB_call(cb, 2, i); + return 1; +} + +/* + * This is the main X9.31 prime derivation function. From parameters Xp1, Xp2 + * and Xp derive the prime p. If the parameters p1 or p2 are not NULL they + * will be returned too: this is needed for testing. + */ + +int BN_X931_derive_prime_ex(BIGNUM *p, BIGNUM *p1, BIGNUM *p2, + const BIGNUM *Xp, const BIGNUM *Xp1, + const BIGNUM *Xp2, const BIGNUM *e, BN_CTX *ctx, + BN_GENCB *cb) +{ + int ret = 0; + + BIGNUM *t, *p1p2, *pm1; + + /* Only even e supported */ + if (!BN_is_odd(e)) + return 0; + + BN_CTX_start(ctx); + if (!p1) + p1 = BN_CTX_get(ctx); + + if (!p2) + p2 = BN_CTX_get(ctx); + + t = BN_CTX_get(ctx); + + p1p2 = BN_CTX_get(ctx); + + pm1 = BN_CTX_get(ctx); + + if (pm1 == NULL) + goto err; + + if (!bn_x931_derive_pi(p1, Xp1, ctx, cb)) + goto err; + + if (!bn_x931_derive_pi(p2, Xp2, ctx, cb)) + goto err; + + if (!BN_mul(p1p2, p1, p2, ctx)) + goto err; + + /* First set p to value of Rp */ + + if (!BN_mod_inverse(p, p2, p1, ctx)) + goto err; + + if (!BN_mul(p, p, p2, ctx)) + goto err; + + if (!BN_mod_inverse(t, p1, p2, ctx)) + goto err; + + if (!BN_mul(t, t, p1, ctx)) + goto err; + + if (!BN_sub(p, p, t)) + goto err; + + if (p->neg && !BN_add(p, p, p1p2)) + goto err; + + /* p now equals Rp */ + + if (!BN_mod_sub(p, p, Xp, p1p2, ctx)) + goto err; + + if (!BN_add(p, p, Xp)) + goto err; + + /* p now equals Yp0 */ + + for (;;) { + int i = 1; + BN_GENCB_call(cb, 0, i++); + if (!BN_copy(pm1, p)) + goto err; + if (!BN_sub_word(pm1, 1)) + goto err; + if (!BN_gcd(t, pm1, e, ctx)) + goto err; + if (BN_is_one(t)) { + /* + * X9.31 specifies 8 MR and 1 Lucas test or any prime test + * offering similar or better guarantees 50 MR is considerably + * better. + */ + int r = BN_is_prime_fasttest_ex(p, 50, ctx, 1, cb); + if (r < 0) + goto err; + if (r) + break; + } + if (!BN_add(p, p, p1p2)) + goto err; + } + + BN_GENCB_call(cb, 3, 0); + + ret = 1; + + err: + + BN_CTX_end(ctx); + + return ret; +} + +/* + * Generate pair of parameters Xp, Xq for X9.31 prime generation. Note: nbits + * parameter is sum of number of bits in both. + */ + +int BN_X931_generate_Xpq(BIGNUM *Xp, BIGNUM *Xq, int nbits, BN_CTX *ctx) +{ + BIGNUM *t; + int i; + /* + * Number of bits for each prime is of the form 512+128s for s = 0, 1, + * ... + */ + if ((nbits < 1024) || (nbits & 0xff)) + return 0; + nbits >>= 1; + /* + * The random value Xp must be between sqrt(2) * 2^(nbits-1) and 2^nbits + * - 1. By setting the top two bits we ensure that the lower bound is + * exceeded. + */ + if (!BN_rand(Xp, nbits, BN_RAND_TOP_TWO, BN_RAND_BOTTOM_ANY)) + goto err; + + BN_CTX_start(ctx); + t = BN_CTX_get(ctx); + if (t == NULL) + goto err; + + for (i = 0; i < 1000; i++) { + if (!BN_rand(Xq, nbits, BN_RAND_TOP_TWO, BN_RAND_BOTTOM_ANY)) + goto err; + /* Check that |Xp - Xq| > 2^(nbits - 100) */ + BN_sub(t, Xp, Xq); + if (BN_num_bits(t) > (nbits - 100)) + break; + } + + BN_CTX_end(ctx); + + if (i < 1000) + return 1; + + return 0; + + err: + BN_CTX_end(ctx); + return 0; +} + +/* + * Generate primes using X9.31 algorithm. Of the values p, p1, p2, Xp1 and + * Xp2 only 'p' needs to be non-NULL. If any of the others are not NULL the + * relevant parameter will be stored in it. Due to the fact that |Xp - Xq| > + * 2^(nbits - 100) must be satisfied Xp and Xq are generated using the + * previous function and supplied as input. + */ + +int BN_X931_generate_prime_ex(BIGNUM *p, BIGNUM *p1, BIGNUM *p2, + BIGNUM *Xp1, BIGNUM *Xp2, + const BIGNUM *Xp, + const BIGNUM *e, BN_CTX *ctx, BN_GENCB *cb) +{ + int ret = 0; + + BN_CTX_start(ctx); + if (Xp1 == NULL) + Xp1 = BN_CTX_get(ctx); + if (Xp2 == NULL) + Xp2 = BN_CTX_get(ctx); + if (Xp1 == NULL || Xp2 == NULL) + goto error; + + if (!BN_rand(Xp1, 101, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY)) + goto error; + if (!BN_rand(Xp2, 101, BN_RAND_TOP_ONE, BN_RAND_BOTTOM_ANY)) + goto error; + if (!BN_X931_derive_prime_ex(p, p1, p2, Xp, Xp1, Xp2, e, ctx, cb)) + goto error; + + ret = 1; + + error: + BN_CTX_end(ctx); + + return ret; + +} |