1 /*
2 * Copyright 2019-2023 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 /*
11 * This implemments a dummy key manager for legacy KDFs that still support the
12 * old way of performing a KDF via EVP_PKEY_derive(). New KDFs should not be
13 * implemented this way. In reality there is no key data for such KDFs, so this
14 * key manager does very little.
15 */
16
17 #include <openssl/core_dispatch.h>
18 #include <openssl/core_names.h>
19 #include <openssl/err.h>
20 #include "prov/implementations.h"
21 #include "prov/providercommon.h"
22 #include "prov/provider_ctx.h"
23 #include "prov/kdfexchange.h"
24
25 static OSSL_FUNC_keymgmt_new_fn kdf_newdata;
26 static OSSL_FUNC_keymgmt_free_fn kdf_freedata;
27 static OSSL_FUNC_keymgmt_has_fn kdf_has;
28
ossl_kdf_data_new(void * provctx)29 KDF_DATA *ossl_kdf_data_new(void *provctx)
30 {
31 KDF_DATA *kdfdata;
32
33 if (!ossl_prov_is_running())
34 return NULL;
35
36 kdfdata = OPENSSL_zalloc(sizeof(*kdfdata));
37 if (kdfdata == NULL)
38 return NULL;
39
40 if (!CRYPTO_NEW_REF(&kdfdata->refcnt, 1)) {
41 OPENSSL_free(kdfdata);
42 return NULL;
43 }
44 kdfdata->libctx = PROV_LIBCTX_OF(provctx);
45
46 return kdfdata;
47 }
48
ossl_kdf_data_free(KDF_DATA * kdfdata)49 void ossl_kdf_data_free(KDF_DATA *kdfdata)
50 {
51 int ref = 0;
52
53 if (kdfdata == NULL)
54 return;
55
56 CRYPTO_DOWN_REF(&kdfdata->refcnt, &ref);
57 if (ref > 0)
58 return;
59
60 CRYPTO_FREE_REF(&kdfdata->refcnt);
61 OPENSSL_free(kdfdata);
62 }
63
ossl_kdf_data_up_ref(KDF_DATA * kdfdata)64 int ossl_kdf_data_up_ref(KDF_DATA *kdfdata)
65 {
66 int ref = 0;
67
68 /* This is effectively doing a new operation on the KDF_DATA and should be
69 * adequately guarded again modules' error states. However, both current
70 * calls here are guarded properly in exchange/kdf_exch.c. Thus, it
71 * could be removed here. The concern is that something in the future
72 * might call this function without adequate guards. It's a cheap call,
73 * it seems best to leave it even though it is currently redundant.
74 */
75 if (!ossl_prov_is_running())
76 return 0;
77
78 CRYPTO_UP_REF(&kdfdata->refcnt, &ref);
79 return 1;
80 }
81
kdf_newdata(void * provctx)82 static void *kdf_newdata(void *provctx)
83 {
84 return ossl_kdf_data_new(provctx);
85 }
86
kdf_freedata(void * kdfdata)87 static void kdf_freedata(void *kdfdata)
88 {
89 ossl_kdf_data_free(kdfdata);
90 }
91
kdf_has(const void * keydata,int selection)92 static int kdf_has(const void *keydata, int selection)
93 {
94 return 1; /* nothing is missing */
95 }
96
97 const OSSL_DISPATCH ossl_kdf_keymgmt_functions[] = {
98 { OSSL_FUNC_KEYMGMT_NEW, (void (*)(void))kdf_newdata },
99 { OSSL_FUNC_KEYMGMT_FREE, (void (*)(void))kdf_freedata },
100 { OSSL_FUNC_KEYMGMT_HAS, (void (*)(void))kdf_has },
101 OSSL_DISPATCH_END
102 };
103
