xref: /aosp_15_r20/system/keymaster/km_openssl/rsa_key.cpp (revision 789431f29546679ab5188a97751fb38e3018d44d)
1 /*
2  * Copyright 2014 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <keymaster/km_openssl/rsa_key.h>
18 
19 #include <keymaster/keymaster_context.h>
20 #include <keymaster/km_openssl/openssl_err.h>
21 #include <keymaster/km_openssl/openssl_utils.h>
22 #include <keymaster/km_openssl/rsa_operation.h>
23 
24 namespace keymaster {
25 
EvpToInternal(const EVP_PKEY * pkey)26 bool RsaKey::EvpToInternal(const EVP_PKEY* pkey) {
27     rsa_key_.reset(EVP_PKEY_get1_RSA(const_cast<EVP_PKEY*>(pkey)));
28     return rsa_key_.get() != nullptr;
29 }
30 
InternalToEvp() const31 EVP_PKEY_Ptr RsaKey::InternalToEvp() const {
32     EVP_PKEY_Ptr pkey(EVP_PKEY_new());
33     if (pkey.get() != nullptr) {
34         if (EVP_PKEY_set1_RSA(pkey.get(), rsa_key_.get()) != 1) {
35             return {};
36         }
37     }
38     return pkey;
39 }
40 
SupportedMode(keymaster_purpose_t purpose,keymaster_padding_t padding)41 bool RsaKey::SupportedMode(keymaster_purpose_t purpose, keymaster_padding_t padding) {
42     switch (purpose) {
43     case KM_PURPOSE_ATTEST_KEY:
44         return true;
45 
46     case KM_PURPOSE_SIGN:
47     case KM_PURPOSE_VERIFY:
48         return padding == KM_PAD_NONE || padding == KM_PAD_RSA_PSS ||
49                padding == KM_PAD_RSA_PKCS1_1_5_SIGN;
50 
51     case KM_PURPOSE_ENCRYPT:
52     case KM_PURPOSE_DECRYPT:
53     case KM_PURPOSE_WRAP:
54         return padding == KM_PAD_RSA_OAEP || padding == KM_PAD_RSA_PKCS1_1_5_ENCRYPT;
55 
56     case KM_PURPOSE_DERIVE_KEY:
57     case KM_PURPOSE_AGREE_KEY:
58         return false;
59     };
60     return false;
61 }
62 
SupportedMode(keymaster_purpose_t purpose,keymaster_digest_t digest)63 bool RsaKey::SupportedMode(keymaster_purpose_t purpose, keymaster_digest_t digest) {
64     switch (purpose) {
65     case KM_PURPOSE_ATTEST_KEY:
66         return true;
67 
68     case KM_PURPOSE_SIGN:
69     case KM_PURPOSE_VERIFY:
70         return digest == KM_DIGEST_NONE || digest == KM_DIGEST_SHA_2_256;
71 
72     case KM_PURPOSE_ENCRYPT:
73     case KM_PURPOSE_DECRYPT:
74     case KM_PURPOSE_WRAP:
75         /* Don't care */
76         break;
77 
78     case KM_PURPOSE_DERIVE_KEY:
79     case KM_PURPOSE_AGREE_KEY:
80         return false;
81     };
82     return true;
83 }
84 
85 }  // namespace keymaster
86