2 * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
5 * Licensed under the Apache License 2.0 (the "License"). You may not use
6 * this file except in compliance with the License. You can obtain a copy
7 * in the file LICENSE in the source distribution or at
8 * https://www.openssl.org/source/license.html
12 * Implementation of the FIPS 140-2 section 4.9.2 Conditional Tests.
16 #include <openssl/evp.h>
17 #include <openssl/core_dispatch.h>
18 #include <openssl/params.h>
19 #include "prov/providercommon.h"
20 #include "prov/provider_ctx.h"
21 #include "internal/cryptlib.h"
22 #include "prov/rand_pool.h"
23 #include "drbg_local.h"
24 #include "prov/seeding.h"
26 typedef struct crng_test_global_st {
27 unsigned char crngt_prev[EVP_MAX_MD_SIZE];
28 RAND_POOL *crngt_pool;
31 static int crngt_get_entropy(OPENSSL_CTX *ctx, RAND_POOL *pool,
32 unsigned char *buf, unsigned char *md,
33 unsigned int *md_size)
43 n = prov_pool_acquire_entropy(pool);
44 if (n >= CRNGT_BUFSIZ) {
45 fmd = EVP_MD_fetch(ctx, "SHA256", "");
48 p = rand_pool_detach(pool);
49 r = EVP_Digest(p, CRNGT_BUFSIZ, md, md_size, fmd, NULL);
51 memcpy(buf, p, CRNGT_BUFSIZ);
52 rand_pool_reattach(pool, p);
59 static void rand_crng_ossl_ctx_free(void *vcrngt_glob)
61 CRNG_TEST_GLOBAL *crngt_glob = vcrngt_glob;
63 rand_pool_free(crngt_glob->crngt_pool);
64 OPENSSL_free(crngt_glob);
67 static void *rand_crng_ossl_ctx_new(OPENSSL_CTX *ctx)
69 unsigned char buf[CRNGT_BUFSIZ];
70 CRNG_TEST_GLOBAL *crngt_glob = OPENSSL_zalloc(sizeof(*crngt_glob));
72 if (crngt_glob == NULL)
75 if ((crngt_glob->crngt_pool
76 = rand_pool_new(0, 1, CRNGT_BUFSIZ, CRNGT_BUFSIZ)) == NULL) {
77 OPENSSL_free(crngt_glob);
80 if (crngt_get_entropy(ctx, crngt_glob->crngt_pool, buf,
81 crngt_glob->crngt_prev, NULL)) {
82 OPENSSL_cleanse(buf, sizeof(buf));
85 rand_pool_free(crngt_glob->crngt_pool);
86 OPENSSL_free(crngt_glob);
90 static const OPENSSL_CTX_METHOD rand_crng_ossl_ctx_method = {
91 rand_crng_ossl_ctx_new,
92 rand_crng_ossl_ctx_free,
95 size_t prov_crngt_get_entropy(PROV_DRBG *drbg,
97 int entropy, size_t min_len, size_t max_len,
98 int prediction_resistance)
100 unsigned char buf[CRNGT_BUFSIZ], md[EVP_MAX_MD_SIZE];
103 size_t q, r = 0, s, t = 0;
105 OPENSSL_CTX *libctx = PROV_LIBRARY_CONTEXT_OF(drbg->provctx);
106 CRNG_TEST_GLOBAL *crngt_glob
107 = openssl_ctx_get_data(libctx, OPENSSL_CTX_RAND_CRNGT_INDEX,
108 &rand_crng_ossl_ctx_method);
110 if (crngt_glob == NULL)
113 if ((pool = rand_pool_new(entropy, 1, min_len, max_len)) == NULL)
116 while ((q = rand_pool_bytes_needed(pool, 1)) > 0 && attempts-- > 0) {
117 s = q > sizeof(buf) ? sizeof(buf) : q;
118 if (!crngt_get_entropy(libctx, crngt_glob->crngt_pool, buf, md,
120 || memcmp(crngt_glob->crngt_prev, md, sz) == 0
121 || !rand_pool_add(pool, buf, s, s * 8))
123 memcpy(crngt_glob->crngt_prev, md, sz);
128 *pout = rand_pool_detach(pool);
130 OPENSSL_cleanse(buf, sizeof(buf));
131 rand_pool_free(pool);
135 void prov_crngt_cleanup_entropy(PROV_DRBG *drbg,
136 unsigned char *out, size_t outlen)
138 OPENSSL_secure_clear_free(out, outlen);