1 /*
2 * Copyright 2015 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/legacy_support/ec_keymaster1_key.h>
18
19 #include <memory>
20 #include <utility>
21
22 #include <keymaster/km_openssl/ecdsa_operation.h>
23 #include <keymaster/logger.h>
24
25 #include "ecdsa_keymaster1_operation.h"
26
27 using std::unique_ptr;
28
29 namespace keymaster {
30
EcdsaKeymaster1KeyFactory(const SoftwareKeyBlobMaker & blob_maker,const KeymasterContext & context,const Keymaster1Engine * engine)31 EcdsaKeymaster1KeyFactory::EcdsaKeymaster1KeyFactory(const SoftwareKeyBlobMaker& blob_maker,
32 const KeymasterContext& context,
33 const Keymaster1Engine* engine)
34 : EcKeyFactory(blob_maker, context), engine_(engine),
35 sign_factory_(new (std::nothrow) EcdsaKeymaster1OperationFactory(KM_PURPOSE_SIGN, engine)),
36 // For pubkey ops we can use the normal operation factories.
37 verify_factory_(new (std::nothrow) EcdsaVerifyOperationFactory) {}
38
is_supported(uint32_t digest)39 static bool is_supported(uint32_t digest) {
40 return digest == KM_DIGEST_NONE || digest == KM_DIGEST_SHA_2_256;
41 }
42
UpdateToWorkAroundUnsupportedDigests(const AuthorizationSet & key_description,AuthorizationSet * new_description)43 static void UpdateToWorkAroundUnsupportedDigests(const AuthorizationSet& key_description,
44 AuthorizationSet* new_description) {
45 bool have_unsupported_digests = false;
46 bool have_digest_none = false;
47 for (const keymaster_key_param_t& entry : key_description) {
48 new_description->push_back(entry);
49
50 if (entry.tag == TAG_DIGEST) {
51 if (entry.enumerated == KM_DIGEST_NONE) {
52 have_digest_none = true;
53 } else if (!is_supported(entry.enumerated)) {
54 LOG_D("Found request for unsupported digest %u", entry.enumerated);
55 have_unsupported_digests = true;
56 }
57 }
58 }
59
60 if (have_unsupported_digests && !have_digest_none) {
61 LOG_I("Adding KM_DIGEST_NONE to key authorization, to enable software digesting");
62 new_description->push_back(TAG_DIGEST, KM_DIGEST_NONE);
63 }
64 }
65
GenerateKey(const AuthorizationSet & key_description,UniquePtr<Key>,const KeymasterBlob &,KeymasterKeyBlob * key_blob,AuthorizationSet * hw_enforced,AuthorizationSet * sw_enforced,CertificateChain *) const66 keymaster_error_t EcdsaKeymaster1KeyFactory::GenerateKey(const AuthorizationSet& key_description,
67 UniquePtr<Key> /* attest_key */,
68 const KeymasterBlob& /* issuer_subject */,
69 KeymasterKeyBlob* key_blob,
70 AuthorizationSet* hw_enforced,
71 AuthorizationSet* sw_enforced,
72 CertificateChain* /* cert_chain */) const {
73 AuthorizationSet key_params_copy;
74 UpdateToWorkAroundUnsupportedDigests(key_description, &key_params_copy);
75
76 keymaster_ec_curve_t ec_curve;
77 uint32_t key_size;
78 keymaster_error_t error = GetCurveAndSize(key_description, &ec_curve, &key_size);
79 if (error != KM_ERROR_OK) {
80 return error;
81 } else if (!key_description.Contains(TAG_KEY_SIZE, key_size)) {
82 key_params_copy.push_back(TAG_KEY_SIZE, key_size);
83 }
84 return engine_->GenerateKey(key_params_copy, key_blob, hw_enforced, sw_enforced);
85 }
86
87 keymaster_error_t
ImportKey(const AuthorizationSet & key_description,keymaster_key_format_t input_key_material_format,const KeymasterKeyBlob & input_key_material,UniquePtr<Key>,const KeymasterBlob &,KeymasterKeyBlob * output_key_blob,AuthorizationSet * hw_enforced,AuthorizationSet * sw_enforced,CertificateChain *) const88 EcdsaKeymaster1KeyFactory::ImportKey(const AuthorizationSet& key_description, //
89 keymaster_key_format_t input_key_material_format, //
90 const KeymasterKeyBlob& input_key_material, //
91 UniquePtr<Key> /* attest_key */, //
92 const KeymasterBlob& /* issuer_subject */,
93 KeymasterKeyBlob* output_key_blob, //
94 AuthorizationSet* hw_enforced, //
95 AuthorizationSet* sw_enforced,
96 CertificateChain* /* cert_chain */) const {
97 AuthorizationSet key_params_copy;
98 UpdateToWorkAroundUnsupportedDigests(key_description, &key_params_copy);
99 return engine_->ImportKey(key_params_copy, input_key_material_format, input_key_material,
100 output_key_blob, hw_enforced, sw_enforced);
101 }
102
LoadKey(KeymasterKeyBlob && key_material,const AuthorizationSet & additional_params,AuthorizationSet && hw_enforced,AuthorizationSet && sw_enforced,UniquePtr<Key> * key) const103 keymaster_error_t EcdsaKeymaster1KeyFactory::LoadKey(KeymasterKeyBlob&& key_material,
104 const AuthorizationSet& additional_params,
105 AuthorizationSet&& hw_enforced,
106 AuthorizationSet&& sw_enforced,
107 UniquePtr<Key>* key) const {
108 if (!key) return KM_ERROR_OUTPUT_PARAMETER_NULL;
109
110 keymaster_error_t error;
111 unique_ptr<EC_KEY, EC_KEY_Delete> ecdsa(
112 engine_->BuildEcKey(key_material, additional_params, &error));
113 if (!ecdsa) return error;
114
115 key->reset(new (std::nothrow)
116 EcdsaKeymaster1Key(ecdsa.release(), std::move(hw_enforced),
117 std::move(sw_enforced), this));
118 if (!(*key)) return KM_ERROR_MEMORY_ALLOCATION_FAILED;
119
120 (*key)->key_material() = std::move(key_material);
121 return KM_ERROR_OK;
122 }
123
124 OperationFactory*
GetOperationFactory(keymaster_purpose_t purpose) const125 EcdsaKeymaster1KeyFactory::GetOperationFactory(keymaster_purpose_t purpose) const {
126 switch (purpose) {
127 case KM_PURPOSE_SIGN:
128 return sign_factory_.get();
129 case KM_PURPOSE_VERIFY:
130 return verify_factory_.get();
131 default:
132 return nullptr;
133 }
134 }
135
136 } // namespace keymaster
137