2 * Copyright (c) 2015 Samsung Electronics Co., Ltd All Rights Reserved
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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
18 * @author Bartłomiej Grzelewski (b.grzelewski@samsung.com)
19 * @author Lukasz Kostyra (l.kostyra@samsung.com)
22 #include <dpl/log/log.h>
24 #include <crypto-backend.h>
26 #include <platform/decider.h>
28 #include <generic-backend/exception.h>
29 #include <sw-backend/store.h>
31 #ifdef TZ_BACKEND_ENABLED
32 #include <tz-backend/store.h>
33 #include <tz-backend/tz-context.h>
35 #include <tee_client_api.h>
36 #include <km_ta_defines.h>
37 #endif // TZ_BACKEND_ENABLED
49 std::string ValueToString(const T& value)
51 std::stringstream str;
52 // we need to re-cast because otherwise stringstream
53 // will write our value incorrectly
54 str << std::setfill('0') << std::setw(2 * sizeof(T)) << std::hex
55 << static_cast<uint64_t>(value);
59 CryptoBackend chooseCryptoBackend(DataType data,
63 #ifdef TZ_BACKEND_ENABLED
64 // user directly point proper backend - we will not discuss with it
65 if (policy.backend == CKM::PolicyBackend::FORCE_SOFTWARE)
66 return CryptoBackend::OpenSSL;
68 // user directly point proper backend - we will not discuss with it
69 if (policy.backend == CKM::PolicyBackend::FORCE_HARDWARE)
70 return CryptoBackend::TrustZone;
72 // For now only software backend supports device encyption key
73 // TODO tz-backend could support the master key, but it would require
74 // hardcoding a known key ID and querying TA whether the key is
77 return CryptoBackend::OpenSSL;
79 // tz-backend allows only for data binary export
80 if (policy.extractable && !data.isBinaryData())
81 return CryptoBackend::OpenSSL;
83 // Use TrustZone only with symmetric keys or unencrypted binary
84 // data until asymmetric cryptography is implemented
85 if (!data.isSKey() && !data.isBinaryData())
86 return CryptoBackend::OpenSSL;
89 LogDebug("Trying to open TA session...");
90 TZ::Internals::TrustZoneContext::Instance();
91 } catch (const Exc::Crypto::InternalError& e) {
92 LogDebug("...failed. Selecting SW backend.");
93 return CryptoBackend::OpenSSL;
96 LogDebug("...succeeded. Selecting TZ backend.");
97 return CryptoBackend::TrustZone;
98 #else // TZ_BACKEND_ENABLED
102 return CryptoBackend::OpenSSL;
103 #endif // TZ_BACKEND_ENABLED
109 : m_swStore(new SW::Store(CryptoBackend::OpenSSL))
110 #ifdef TZ_BACKEND_ENABLED
111 , m_tzStore(new TZ::Store(CryptoBackend::TrustZone))
116 GStore &Decider::getStore(const Token &token) const
118 return getStore(token.backendId);
121 GStore &Decider::getStore(CryptoBackend cryptoBackend) const
123 GStore *gStore = NULL;
125 if (cryptoBackend == CryptoBackend::OpenSSL)
126 gStore = m_swStore.get();
127 #ifdef TZ_BACKEND_ENABLED
128 if (cryptoBackend == CryptoBackend::TrustZone)
129 gStore = m_tzStore.get();
134 ThrowErr(Exc::Crypto::InternalError,
135 "Backend not available. BackendId: ", (int)cryptoBackend);
138 GStore &Decider::getStore(DataType data, const Policy &policy, bool encrypted) const
140 return getStore(chooseCryptoBackend(data, policy, encrypted));
143 } // namespace Crypto