xref: /aosp_15_r20/external/tink/cc/keyderivation/key_derivation_key_templates.cc (revision e7b1675dde1b92d52ec075b0a92829627f2c52a5)
1 // Copyright 2019 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //     http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 ////////////////////////////////////////////////////////////////////////////////
16 
17 #include "tink/keyderivation/key_derivation_key_templates.h"
18 
19 #include <memory>
20 
21 #include "tink/keyderivation/internal/prf_based_deriver_key_manager.h"
22 #include "tink/subtle/random.h"
23 
24 namespace crypto {
25 namespace tink {
26 
27 using ::google::crypto::tink::KeyTemplate;
28 using ::google::crypto::tink::PrfBasedDeriverKeyFormat;
29 
30 util::StatusOr<KeyTemplate>
CreatePrfBasedKeyTemplate(const KeyTemplate & prf_key_template,const KeyTemplate & derived_key_template)31 KeyDerivationKeyTemplates::CreatePrfBasedKeyTemplate(
32     const KeyTemplate& prf_key_template,
33     const KeyTemplate& derived_key_template) {
34   KeyTemplate key_template;
35   key_template.set_type_url(
36       internal::PrfBasedDeriverKeyManager().get_key_type());
37   key_template.set_output_prefix_type(
38       derived_key_template.output_prefix_type());
39 
40   PrfBasedDeriverKeyFormat format;
41   *format.mutable_prf_key_template() = prf_key_template;
42   *format.mutable_params()->mutable_derived_key_template() =
43       derived_key_template;
44   format.SerializeToString(key_template.mutable_value());
45 
46   // Verify `key_template` is derivable.
47   util::StatusOr<std::unique_ptr<KeysetHandle>> handle =
48       KeysetHandle::GenerateNew(key_template);
49   if (!handle.ok()) {
50     return handle.status();
51   }
52   util::StatusOr<std::unique_ptr<KeysetDeriver>> deriver =
53       (*handle)->GetPrimitive<KeysetDeriver>();
54   if (!deriver.ok()) {
55     return deriver.status();
56   }
57 
58   return key_template;
59 }
60 
61 }  // namespace tink
62 }  // namespace crypto
63