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 "internal/rand_int.h"
18 #include "internal/thread_once.h"
19 #include "internal/cryptlib.h"
22 typedef struct crng_test_global_st {
23 unsigned char crngt_prev[EVP_MAX_MD_SIZE];
24 RAND_POOL *crngt_pool;
27 int (*crngt_get_entropy)(OPENSSL_CTX *, unsigned char *, unsigned char *,
29 = &rand_crngt_get_entropy_cb;
31 static void rand_crng_ossl_ctx_free(void *vcrngt_glob)
33 CRNG_TEST_GLOBAL *crngt_glob = vcrngt_glob;
35 rand_pool_free(crngt_glob->crngt_pool);
36 OPENSSL_free(crngt_glob);
39 static void *rand_crng_ossl_ctx_new(OPENSSL_CTX *ctx)
41 unsigned char buf[CRNGT_BUFSIZ];
42 CRNG_TEST_GLOBAL *crngt_glob = OPENSSL_zalloc(sizeof(*crngt_glob));
44 if (crngt_glob == NULL)
47 if ((crngt_glob->crngt_pool
48 = rand_pool_new(0, CRNGT_BUFSIZ, CRNGT_BUFSIZ)) == NULL) {
49 OPENSSL_free(crngt_glob);
52 if (crngt_get_entropy(ctx, buf, crngt_glob->crngt_prev, NULL)) {
53 OPENSSL_cleanse(buf, sizeof(buf));
56 rand_pool_free(crngt_glob->crngt_pool);
57 OPENSSL_free(crngt_glob);
61 static const OPENSSL_CTX_METHOD rand_crng_ossl_ctx_method = {
62 rand_crng_ossl_ctx_new,
63 rand_crng_ossl_ctx_free,
66 int rand_crngt_get_entropy_cb(OPENSSL_CTX *ctx,
69 unsigned int *md_size)
74 CRNG_TEST_GLOBAL *crngt_glob
75 = openssl_ctx_get_data(ctx, OPENSSL_CTX_RAND_CRNGT_INDEX,
76 &rand_crng_ossl_ctx_method);
78 if (crngt_glob == NULL)
81 n = rand_pool_acquire_entropy(crngt_glob->crngt_pool);
82 if (n >= CRNGT_BUFSIZ) {
83 p = rand_pool_detach(crngt_glob->crngt_pool);
84 r = EVP_Digest(p, CRNGT_BUFSIZ, md, md_size, EVP_sha256(), NULL);
86 memcpy(buf, p, CRNGT_BUFSIZ);
87 rand_pool_reattach(crngt_glob->crngt_pool, p);
93 size_t rand_crngt_get_entropy(RAND_DRBG *drbg,
95 int entropy, size_t min_len, size_t max_len,
96 int prediction_resistance)
98 unsigned char buf[CRNGT_BUFSIZ], md[EVP_MAX_MD_SIZE];
101 size_t q, r = 0, s, t = 0;
103 CRNG_TEST_GLOBAL *crngt_glob
104 = openssl_ctx_get_data(drbg->libctx, OPENSSL_CTX_RAND_CRNGT_INDEX,
105 &rand_crng_ossl_ctx_method);
107 if (crngt_glob == NULL)
110 if ((pool = rand_pool_new(entropy, min_len, max_len)) == NULL)
113 while ((q = rand_pool_bytes_needed(pool, 1)) > 0 && attempts-- > 0) {
114 s = q > sizeof(buf) ? sizeof(buf) : q;
115 if (!crngt_get_entropy(drbg->libctx, buf, md, &sz)
116 || memcmp(crngt_glob->crngt_prev, md, sz) == 0
117 || !rand_pool_add(pool, buf, s, s * 8))
119 memcpy(crngt_glob->crngt_prev, md, sz);
124 *pout = rand_pool_detach(pool);
126 OPENSSL_cleanse(buf, sizeof(buf));
127 rand_pool_free(pool);
131 void rand_crngt_cleanup_entropy(RAND_DRBG *drbg,
132 unsigned char *out, size_t outlen)
134 OPENSSL_secure_clear_free(out, outlen);