1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
|
/*
* Copyright (c) 2019, The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define LOG_TAG "credstore"
#include <algorithm>
#include <optional>
#include <android-base/logging.h>
#include <android/hardware/security/keymint/IRemotelyProvisionedComponent.h>
#include <android/hardware/security/keymint/RpcHardwareInfo.h>
#include <android/security/remoteprovisioning/IRemotelyProvisionedKeyPool.h>
#include <android/security/remoteprovisioning/RemotelyProvisionedKey.h>
#include <binder/IPCThreadState.h>
#include <binder/IServiceManager.h>
#include "Credential.h"
#include "CredentialData.h"
#include "CredentialStore.h"
#include "Session.h"
#include "Util.h"
#include "WritableCredential.h"
namespace android {
namespace security {
namespace identity {
namespace {
using ::android::hardware::security::keymint::IRemotelyProvisionedComponent;
using ::android::hardware::security::keymint::RpcHardwareInfo;
using ::android::security::remoteprovisioning::IRemotelyProvisionedKeyPool;
using ::android::security::remoteprovisioning::RemotelyProvisionedKey;
std::optional<std::string>
getRemotelyProvisionedComponentId(const sp<IIdentityCredentialStore>& hal) {
auto init = [](const sp<IIdentityCredentialStore>& hal) -> std::optional<std::string> {
sp<IRemotelyProvisionedComponent> remotelyProvisionedComponent;
Status status = hal->getRemotelyProvisionedComponent(&remotelyProvisionedComponent);
if (!status.isOk()) {
LOG(ERROR) << "Error getting remotely provisioned component: " << status;
return std::nullopt;
}
RpcHardwareInfo rpcHwInfo;
status = remotelyProvisionedComponent->getHardwareInfo(&rpcHwInfo);
if (!status.isOk()) {
LOG(ERROR) << "Error getting remotely provisioned component hardware info: " << status;
return std::nullopt;
}
if (!rpcHwInfo.uniqueId) {
LOG(ERROR) << "Remotely provisioned component is missing a unique id, which is "
<< "required for credential key remotely provisioned attestation keys. "
<< "This is a bug in the vendor implementation.";
return std::nullopt;
}
// This id is required to later fetch remotely provisioned attestation keys.
return *rpcHwInfo.uniqueId;
};
static std::optional<std::string> id = init(hal);
return id;
}
} // namespace
CredentialStore::CredentialStore(const std::string& dataPath, sp<IIdentityCredentialStore> hal)
: dataPath_(dataPath), hal_(hal) {}
bool CredentialStore::init() {
Status status = hal_->getHardwareInformation(&hwInfo_);
if (!status.isOk()) {
LOG(ERROR) << "Error getting hardware information: " << status.toString8();
return false;
}
halApiVersion_ = hal_->getInterfaceVersion();
if (hwInfo_.isRemoteKeyProvisioningSupported) {
keyPool_ = android::waitForService<IRemotelyProvisionedKeyPool>(
IRemotelyProvisionedKeyPool::descriptor);
if (keyPool_.get() == nullptr) {
LOG(ERROR) << "Error getting IRemotelyProvisionedKeyPool HAL with service name '"
<< IRemotelyProvisionedKeyPool::descriptor << "'";
return false;
}
}
LOG(INFO) << "Connected to Identity Credential HAL with API version " << halApiVersion_
<< " and name '" << hwInfo_.credentialStoreName << "' authored by '"
<< hwInfo_.credentialStoreAuthorName << "' with chunk size " << hwInfo_.dataChunkSize
<< " and directoAccess set to " << (hwInfo_.isDirectAccess ? "true" : "false");
return true;
}
CredentialStore::~CredentialStore() {}
Status CredentialStore::getSecurityHardwareInfo(SecurityHardwareInfoParcel* _aidl_return) {
SecurityHardwareInfoParcel info;
info.directAccess = hwInfo_.isDirectAccess;
info.supportedDocTypes = hwInfo_.supportedDocTypes;
*_aidl_return = info;
return Status::ok();
};
Status CredentialStore::createCredential(const std::string& credentialName,
const std::string& docType,
sp<IWritableCredential>* _aidl_return) {
uid_t callingUid = android::IPCThreadState::self()->getCallingUid();
optional<bool> credentialExists =
CredentialData::credentialExists(dataPath_, callingUid, credentialName);
if (!credentialExists.has_value()) {
return Status::fromServiceSpecificError(
ERROR_GENERIC, "Error determining if credential with given name exists");
}
if (credentialExists.value()) {
return Status::fromServiceSpecificError(ERROR_ALREADY_PERSONALIZED,
"Credential with given name already exists");
}
if (hwInfo_.supportedDocTypes.size() > 0) {
if (std::find(hwInfo_.supportedDocTypes.begin(), hwInfo_.supportedDocTypes.end(),
docType) == hwInfo_.supportedDocTypes.end()) {
return Status::fromServiceSpecificError(ERROR_DOCUMENT_TYPE_NOT_SUPPORTED,
"No support for given document type");
}
}
sp<IWritableIdentityCredential> halWritableCredential;
Status status = hal_->createCredential(docType, false, &halWritableCredential);
if (!status.isOk()) {
return halStatusToGenericError(status);
}
if (hwInfo_.isRemoteKeyProvisioningSupported) {
status = setRemotelyProvisionedAttestationKey(halWritableCredential.get());
if (!status.isOk()) {
return halStatusToGenericError(status);
}
}
sp<IWritableCredential> writableCredential = new WritableCredential(
dataPath_, credentialName, docType, false, hwInfo_, halWritableCredential);
*_aidl_return = writableCredential;
return Status::ok();
}
Status CredentialStore::getCredentialCommon(const std::string& credentialName, int32_t cipherSuite,
sp<IPresentationSession> halSessionBinder,
sp<ICredential>* _aidl_return) {
*_aidl_return = nullptr;
uid_t callingUid = android::IPCThreadState::self()->getCallingUid();
optional<bool> credentialExists =
CredentialData::credentialExists(dataPath_, callingUid, credentialName);
if (!credentialExists.has_value()) {
return Status::fromServiceSpecificError(
ERROR_GENERIC, "Error determining if credential with given name exists");
}
if (!credentialExists.value()) {
return Status::fromServiceSpecificError(ERROR_NO_SUCH_CREDENTIAL,
"Credential with given name doesn't exist");
}
// Note: IdentityCredentialStore.java's CipherSuite enumeration and CipherSuite from the
// HAL is manually kept in sync. So this cast is safe.
sp<Credential> credential =
new Credential(CipherSuite(cipherSuite), dataPath_, credentialName, callingUid, hwInfo_,
hal_, halSessionBinder, halApiVersion_);
Status loadStatus = credential->ensureOrReplaceHalBinder();
if (!loadStatus.isOk()) {
LOG(ERROR) << "Error loading credential";
} else {
*_aidl_return = credential;
}
return loadStatus;
}
Status CredentialStore::getCredentialByName(const std::string& credentialName, int32_t cipherSuite,
sp<ICredential>* _aidl_return) {
return getCredentialCommon(credentialName, cipherSuite, nullptr, _aidl_return);
}
Status CredentialStore::createPresentationSession(int32_t cipherSuite, sp<ISession>* _aidl_return) {
sp<IPresentationSession> halPresentationSession;
Status status =
hal_->createPresentationSession(CipherSuite(cipherSuite), &halPresentationSession);
if (!status.isOk()) {
return halStatusToGenericError(status);
}
*_aidl_return = new Session(cipherSuite, halPresentationSession, this);
return Status::ok();
}
Status CredentialStore::setRemotelyProvisionedAttestationKey(
IWritableIdentityCredential* halWritableCredential) {
std::optional<std::string> rpcId = getRemotelyProvisionedComponentId(hal_);
if (!rpcId) {
return Status::fromServiceSpecificError(ERROR_GENERIC,
"Error getting remotely provisioned component id");
}
uid_t callingUid = android::IPCThreadState::self()->getCallingUid();
RemotelyProvisionedKey key;
Status status = keyPool_->getAttestationKey(callingUid, *rpcId, &key);
if (!status.isOk()) {
LOG(WARNING) << "Unable to fetch remotely provisioned attestation key, falling back "
<< "to the factory-provisioned attestation key.";
return Status::ok();
}
status = halWritableCredential->setRemotelyProvisionedAttestationKey(key.keyBlob,
key.encodedCertChain);
if (!status.isOk()) {
LOG(ERROR) << "Error setting remotely provisioned attestation key on credential";
return status;
}
return Status::ok();
}
} // namespace identity
} // namespace security
} // namespace android
|
