1/*
2 * Copyright 2020-2021 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/core_dispatch.h>
11#include "prov/seeding.h"
12
13static OSSL_FUNC_get_entropy_fn *c_get_entropy = NULL;
14static OSSL_FUNC_cleanup_entropy_fn *c_cleanup_entropy = NULL;
15static OSSL_FUNC_get_nonce_fn *c_get_nonce = NULL;
16static OSSL_FUNC_cleanup_nonce_fn *c_cleanup_nonce = NULL;
17
18int ossl_prov_seeding_from_dispatch(const OSSL_DISPATCH *fns)
19{
20    for (; fns->function_id != 0; fns++) {
21        /*
22         * We do not support the scenario of an application linked against
23         * multiple versions of libcrypto (e.g. one static and one dynamic), but
24         * sharing a single fips.so. We do a simple sanity check here.
25         */
26#define set_func(c, f) \
27    do { if (c == NULL) c = f; else if (c != f) return 0; } while (0)
28        switch (fns->function_id) {
29        case OSSL_FUNC_GET_ENTROPY:
30            set_func(c_get_entropy, OSSL_FUNC_get_entropy(fns));
31            break;
32        case OSSL_FUNC_CLEANUP_ENTROPY:
33            set_func(c_cleanup_entropy, OSSL_FUNC_cleanup_entropy(fns));
34            break;
35        case OSSL_FUNC_GET_NONCE:
36            set_func(c_get_nonce, OSSL_FUNC_get_nonce(fns));
37            break;
38        case OSSL_FUNC_CLEANUP_NONCE:
39            set_func(c_cleanup_nonce, OSSL_FUNC_cleanup_nonce(fns));
40            break;
41        }
42#undef set_func
43    }
44    return 1;
45}
46
47size_t ossl_prov_get_entropy(PROV_CTX *prov_ctx, unsigned char **pout,
48                             int entropy, size_t min_len, size_t max_len)
49{
50    if (c_get_entropy == NULL)
51        return 0;
52    return c_get_entropy(ossl_prov_ctx_get0_handle(prov_ctx),
53                         pout, entropy, min_len, max_len);
54}
55
56void ossl_prov_cleanup_entropy(PROV_CTX *prov_ctx, unsigned char *buf,
57                               size_t len)
58{
59    if (c_cleanup_entropy != NULL)
60        c_cleanup_entropy(ossl_prov_ctx_get0_handle(prov_ctx), buf, len);
61}
62
63size_t ossl_prov_get_nonce(PROV_CTX *prov_ctx, unsigned char **pout,
64                           size_t min_len, size_t max_len,
65                           const void *salt,size_t salt_len)
66{
67    if (c_get_nonce == NULL)
68        return 0;
69    return c_get_nonce(ossl_prov_ctx_get0_handle(prov_ctx), pout,
70                       min_len, max_len, salt, salt_len);
71}
72
73void ossl_prov_cleanup_nonce(PROV_CTX *prov_ctx, unsigned char *buf, size_t len)
74{
75    if (c_cleanup_nonce != NULL)
76        c_cleanup_nonce(ossl_prov_ctx_get0_handle(prov_ctx), buf, len);
77}
78