2 * Copyright 2019-2020 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 <openssl/self_test.h>
20 #include "prov/providercommon.h"
21 #include "prov/provider_ctx.h"
22 #include "internal/cryptlib.h"
23 #include "prov/rand_pool.h"
24 #include "drbg_local.h"
25 #include "prov/seeding.h"
27 typedef struct crng_test_global_st {
28 unsigned char crngt_prev[EVP_MAX_MD_SIZE];
29 RAND_POOL *crngt_pool;
32 static int crngt_get_entropy(OSSL_LIB_CTX *ctx, RAND_POOL *pool,
33 unsigned char *buf, unsigned char *md,
34 unsigned int *md_size)
44 n = prov_pool_acquire_entropy(pool);
45 if (n >= CRNGT_BUFSIZ) {
46 fmd = EVP_MD_fetch(ctx, "SHA256", "");
49 p = rand_pool_detach(pool);
50 r = EVP_Digest(p, CRNGT_BUFSIZ, md, md_size, fmd, NULL);
52 memcpy(buf, p, CRNGT_BUFSIZ);
53 rand_pool_reattach(pool, p);
60 static void rand_crng_ossl_ctx_free(void *vcrngt_glob)
62 CRNG_TEST_GLOBAL *crngt_glob = vcrngt_glob;
64 rand_pool_free(crngt_glob->crngt_pool);
65 OPENSSL_free(crngt_glob);
68 static void *rand_crng_ossl_ctx_new(OSSL_LIB_CTX *ctx)
70 unsigned char buf[CRNGT_BUFSIZ];
71 CRNG_TEST_GLOBAL *crngt_glob = OPENSSL_zalloc(sizeof(*crngt_glob));
73 if (crngt_glob == NULL)
76 if ((crngt_glob->crngt_pool
77 = rand_pool_new(0, 1, CRNGT_BUFSIZ, CRNGT_BUFSIZ)) == NULL) {
78 OPENSSL_free(crngt_glob);
81 if (crngt_get_entropy(ctx, crngt_glob->crngt_pool, buf,
82 crngt_glob->crngt_prev, NULL)) {
83 OPENSSL_cleanse(buf, sizeof(buf));
86 rand_pool_free(crngt_glob->crngt_pool);
87 OPENSSL_free(crngt_glob);
91 static const OSSL_LIB_CTX_METHOD rand_crng_ossl_ctx_method = {
92 rand_crng_ossl_ctx_new,
93 rand_crng_ossl_ctx_free,
96 static int prov_crngt_compare_previous(const unsigned char *prev,
97 const unsigned char *cur,
100 const int res = memcmp(prev, cur, sz) != 0;
103 ossl_set_error_state(OSSL_SELF_TEST_TYPE_CRNG);
107 size_t prov_crngt_get_entropy(PROV_DRBG *drbg,
108 unsigned char **pout,
109 int entropy, size_t min_len, size_t max_len,
110 int prediction_resistance)
112 unsigned char buf[CRNGT_BUFSIZ], md[EVP_MAX_MD_SIZE];
115 size_t q, r = 0, s, t = 0;
116 int attempts = 3, crng_test_pass = 1;
117 OSSL_LIB_CTX *libctx = PROV_LIBCTX_OF(drbg->provctx);
118 CRNG_TEST_GLOBAL *crngt_glob
119 = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_RAND_CRNGT_INDEX,
120 &rand_crng_ossl_ctx_method);
121 OSSL_CALLBACK *stcb = NULL;
122 void *stcbarg = NULL;
123 OSSL_SELF_TEST *st = NULL;
125 if (crngt_glob == NULL)
128 if ((pool = rand_pool_new(entropy, 1, min_len, max_len)) == NULL)
131 OSSL_SELF_TEST_get_callback(libctx, &stcb, &stcbarg);
133 st = OSSL_SELF_TEST_new(stcb, stcbarg);
136 OSSL_SELF_TEST_onbegin(st, OSSL_SELF_TEST_TYPE_CRNG,
137 OSSL_SELF_TEST_DESC_RNG);
140 while ((q = rand_pool_bytes_needed(pool, 1)) > 0 && attempts-- > 0) {
141 s = q > sizeof(buf) ? sizeof(buf) : q;
142 if (!crngt_get_entropy(libctx, crngt_glob->crngt_pool, buf, md, &sz))
144 /* Force a failure here if the callback returns 1 */
145 if (OSSL_SELF_TEST_oncorrupt_byte(st, md))
146 memcpy(md, crngt_glob->crngt_prev, sz);
147 if (!prov_crngt_compare_previous(crngt_glob->crngt_prev, md, sz)) {
151 if (!rand_pool_add(pool, buf, s, s * 8))
153 memcpy(crngt_glob->crngt_prev, md, sz);
158 *pout = rand_pool_detach(pool);
160 OSSL_SELF_TEST_onend(st, crng_test_pass);
161 OSSL_SELF_TEST_free(st);
162 OPENSSL_cleanse(buf, sizeof(buf));
163 rand_pool_free(pool);
167 void prov_crngt_cleanup_entropy(PROV_DRBG *drbg,
168 unsigned char *out, size_t outlen)
170 OPENSSL_secure_clear_free(out, outlen);