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
21 #include <keymaster/km_openssl/ecdsa_operation.h>
22 #include <keymaster/logger.h>
23
24 #include "ecdsa_keymaster1_operation.h"
25
26 using std::unique_ptr;
27
28 namespace keymaster {
29
EcdsaKeymaster1KeyFactory(const SoftwareKeyBlobMaker & blob_maker,const KeymasterContext & context,const Keymaster1Engine * engine)30 EcdsaKeymaster1KeyFactory::EcdsaKeymaster1KeyFactory(const SoftwareKeyBlobMaker& blob_maker,
31 const KeymasterContext& context,
32 const Keymaster1Engine* engine)
33 : EcKeyFactory(blob_maker, context), engine_(engine),
34 sign_factory_(new EcdsaKeymaster1OperationFactory(KM_PURPOSE_SIGN, engine)),
35 // For pubkey ops we can use the normal operation factories.
36 verify_factory_(new EcdsaVerifyOperationFactory) {}
37
is_supported(uint32_t digest)38 static bool is_supported(uint32_t digest) {
39 return digest == KM_DIGEST_NONE || digest == KM_DIGEST_SHA_2_256;
40 }
41
UpdateToWorkAroundUnsupportedDigests(const AuthorizationSet & key_description,AuthorizationSet * new_description)42 static void UpdateToWorkAroundUnsupportedDigests(const AuthorizationSet& key_description,
43 AuthorizationSet* new_description) {
44 bool have_unsupported_digests = false;
45 bool have_digest_none = false;
46 for (const keymaster_key_param_t& entry : key_description) {
47 new_description->push_back(entry);
48
49 if (entry.tag == TAG_DIGEST) {
50 if (entry.enumerated == KM_DIGEST_NONE) {
51 have_digest_none = true;
52 } else if (!is_supported(entry.enumerated)) {
53 LOG_D("Found request for unsupported digest %u", entry.enumerated);
54 have_unsupported_digests = true;
55 }
56 }
57 }
58
59 if (have_unsupported_digests && !have_digest_none) {
60 LOG_I("Adding KM_DIGEST_NONE to key authorization, to enable software digesting", 0);
61 new_description->push_back(TAG_DIGEST, KM_DIGEST_NONE);
62 }
63 }
64
GenerateKey(const AuthorizationSet & key_description,UniquePtr<Key>,const KeymasterBlob &,KeymasterKeyBlob * key_blob,AuthorizationSet * hw_enforced,AuthorizationSet * sw_enforced,CertificateChain *) const65 keymaster_error_t EcdsaKeymaster1KeyFactory::GenerateKey(const AuthorizationSet& key_description,
66 UniquePtr<Key> /* attest_key */,
67 const KeymasterBlob& /* issuer_subject */,
68 KeymasterKeyBlob* key_blob,
69 AuthorizationSet* hw_enforced,
70 AuthorizationSet* sw_enforced,
71 CertificateChain* /* cert_chain */) const {
72 AuthorizationSet key_params_copy;
73 UpdateToWorkAroundUnsupportedDigests(key_description, &key_params_copy);
74
75 keymaster_ec_curve_t ec_curve;
76 uint32_t key_size;
77 keymaster_error_t error = GetCurveAndSize(key_description, &ec_curve, &key_size);
78 if (error != KM_ERROR_OK) {
79 return error;
80 } else if (!key_description.Contains(TAG_KEY_SIZE, key_size)) {
81 key_params_copy.push_back(TAG_KEY_SIZE, key_size);
82 }
83 return engine_->GenerateKey(key_params_copy, key_blob, hw_enforced, sw_enforced);
84 }
85
86 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 *) const87 EcdsaKeymaster1KeyFactory::ImportKey(const AuthorizationSet& key_description, //
88 keymaster_key_format_t input_key_material_format, //
89 const KeymasterKeyBlob& input_key_material, //
90 UniquePtr<Key> /* attest_key */, //
91 const KeymasterBlob& /* issuer_subject */,
92 KeymasterKeyBlob* output_key_blob, //
93 AuthorizationSet* hw_enforced, //
94 AuthorizationSet* sw_enforced,
95 CertificateChain* /* cert_chain */) const {
96 AuthorizationSet key_params_copy;
97 UpdateToWorkAroundUnsupportedDigests(key_description, &key_params_copy);
98 return engine_->ImportKey(key_params_copy, input_key_material_format, input_key_material,
99 output_key_blob, hw_enforced, sw_enforced);
100 }
101
LoadKey(KeymasterKeyBlob && key_material,const AuthorizationSet & additional_params,AuthorizationSet && hw_enforced,AuthorizationSet && sw_enforced,UniquePtr<Key> * key) const102 keymaster_error_t EcdsaKeymaster1KeyFactory::LoadKey(KeymasterKeyBlob&& key_material,
103 const AuthorizationSet& additional_params,
104 AuthorizationSet&& hw_enforced,
105 AuthorizationSet&& sw_enforced,
106 UniquePtr<Key>* key) const {
107 if (!key) return KM_ERROR_OUTPUT_PARAMETER_NULL;
108
109 keymaster_error_t error;
110 unique_ptr<EC_KEY, EC_KEY_Delete> ecdsa(
111 engine_->BuildEcKey(key_material, additional_params, &error));
112 if (!ecdsa) return error;
113
114 key->reset(new (std::nothrow)
115 EcdsaKeymaster1Key(ecdsa.release(), move(hw_enforced), move(sw_enforced), this));
116 if (!(*key)) return KM_ERROR_MEMORY_ALLOCATION_FAILED;
117
118 (*key)->key_material() = move(key_material);
119 return KM_ERROR_OK;
120 }
121
122 OperationFactory*
GetOperationFactory(keymaster_purpose_t purpose) const123 EcdsaKeymaster1KeyFactory::GetOperationFactory(keymaster_purpose_t purpose) const {
124 switch (purpose) {
125 case KM_PURPOSE_SIGN:
126 return sign_factory_.get();
127 case KM_PURPOSE_VERIFY:
128 return verify_factory_.get();
129 default:
130 return nullptr;
131 }
132 }
133
134 } // namespace keymaster
135