1 /* 2 * Copyright 2016-2020 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 #include <openssl/dh.h> 11 #include "internal/refcount.h" 12 #include "internal/ffc.h" 13 14 #define DH_MIN_MODULUS_BITS 512 15 16 struct dh_st { 17 /* 18 * This first argument is used to pick up errors when a DH is passed 19 * instead of a EVP_PKEY 20 */ 21 int pad; 22 int version; 23 FFC_PARAMS params; 24 /* max generated private key length (can be less than len(q)) */ 25 int32_t length; 26 BIGNUM *pub_key; /* g^x % p */ 27 BIGNUM *priv_key; /* x */ 28 int flags; 29 BN_MONT_CTX *method_mont_p; 30 CRYPTO_REF_COUNT references; 31 #ifndef FIPS_MODULE 32 CRYPTO_EX_DATA ex_data; 33 ENGINE *engine; 34 #endif 35 OSSL_LIB_CTX *libctx; 36 const DH_METHOD *meth; 37 CRYPTO_RWLOCK *lock; 38 39 /* Provider data */ 40 size_t dirty_cnt; /* If any key material changes, increment this */ 41 }; 42 43 struct dh_method { 44 char *name; 45 /* Methods here */ 46 int (*generate_key) (DH *dh); 47 int (*compute_key) (unsigned char *key, const BIGNUM *pub_key, DH *dh); 48 49 /* Can be null */ 50 int (*bn_mod_exp) (const DH *dh, BIGNUM *r, const BIGNUM *a, 51 const BIGNUM *p, const BIGNUM *m, BN_CTX *ctx, 52 BN_MONT_CTX *m_ctx); 53 int (*init) (DH *dh); 54 int (*finish) (DH *dh); 55 int flags; 56 char *app_data; 57 /* If this is non-NULL, it will be used to generate parameters */ 58 int (*generate_params) (DH *dh, int prime_len, int generator, 59 BN_GENCB *cb); 60 }; 61