1 /*
2 * Copyright 2020, 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 #define LOG_TAG "android.hardware.security.keymint-impl"
18 #include <android-base/logging.h>
19
20 #include "KeyMintUtils.h"
21
22 namespace aidl::android::hardware::security::keymint::km_utils {
23
24 namespace {
25
26 using keymaster::hton;
27
kmEnumParam2Aidl(const keymaster_key_param_t & param)28 KeyParameter kmEnumParam2Aidl(const keymaster_key_param_t& param) {
29 switch (param.tag) {
30 case KM_TAG_PURPOSE:
31 return KeyParameter{Tag::PURPOSE, KeyParameterValue::make<KeyParameterValue::keyPurpose>(
32 static_cast<KeyPurpose>(param.enumerated))};
33 case KM_TAG_ALGORITHM:
34 return KeyParameter{Tag::ALGORITHM, KeyParameterValue::make<KeyParameterValue::algorithm>(
35 static_cast<Algorithm>(param.enumerated))};
36 case KM_TAG_BLOCK_MODE:
37 return KeyParameter{Tag::BLOCK_MODE, KeyParameterValue::make<KeyParameterValue::blockMode>(
38 static_cast<BlockMode>(param.enumerated))};
39 case KM_TAG_DIGEST:
40 return KeyParameter{Tag::DIGEST, KeyParameterValue::make<KeyParameterValue::digest>(
41 static_cast<Digest>(param.enumerated))};
42 case KM_TAG_PADDING:
43 return KeyParameter{Tag::PADDING, KeyParameterValue::make<KeyParameterValue::paddingMode>(
44 static_cast<PaddingMode>(param.enumerated))};
45 case KM_TAG_EC_CURVE:
46 return KeyParameter{Tag::EC_CURVE, KeyParameterValue::make<KeyParameterValue::ecCurve>(
47 static_cast<EcCurve>(param.enumerated))};
48 case KM_TAG_USER_AUTH_TYPE:
49 return KeyParameter{Tag::USER_AUTH_TYPE,
50 KeyParameterValue::make<KeyParameterValue::hardwareAuthenticatorType>(
51 static_cast<HardwareAuthenticatorType>(param.enumerated))};
52 case KM_TAG_ORIGIN:
53 return KeyParameter{Tag::ORIGIN, KeyParameterValue::make<KeyParameterValue::origin>(
54 static_cast<KeyOrigin>(param.enumerated))};
55 case KM_TAG_BLOB_USAGE_REQUIREMENTS:
56 case KM_TAG_KDF:
57 default:
58 return KeyParameter{Tag::INVALID, false};
59 }
60 }
61
62 keymaster_key_param_t kInvalidTag{.tag = KM_TAG_INVALID, .integer = 0};
63
64 template <KeyParameterValue::Tag aidl_tag>
aidlEnumVal2Km(keymaster_tag_t km_tag,const KeyParameterValue & value)65 keymaster_key_param_t aidlEnumVal2Km(keymaster_tag_t km_tag, const KeyParameterValue& value) {
66 return value.getTag() == aidl_tag
67 ? keymaster_param_enum(km_tag, static_cast<uint32_t>(value.get<aidl_tag>()))
68 : kInvalidTag;
69 }
70
aidlEnumParam2Km(const KeyParameter & param)71 keymaster_key_param_t aidlEnumParam2Km(const KeyParameter& param) {
72 auto tag = km_utils::legacy_enum_conversion(param.tag);
73 switch (tag) {
74 case KM_TAG_PURPOSE:
75 return aidlEnumVal2Km<KeyParameterValue::keyPurpose>(tag, param.value);
76 case KM_TAG_ALGORITHM:
77 return aidlEnumVal2Km<KeyParameterValue::algorithm>(tag, param.value);
78 case KM_TAG_BLOCK_MODE:
79 return aidlEnumVal2Km<KeyParameterValue::blockMode>(tag, param.value);
80 case KM_TAG_DIGEST:
81 case KM_TAG_RSA_OAEP_MGF_DIGEST:
82 return aidlEnumVal2Km<KeyParameterValue::digest>(tag, param.value);
83 case KM_TAG_PADDING:
84 return aidlEnumVal2Km<KeyParameterValue::paddingMode>(tag, param.value);
85 case KM_TAG_EC_CURVE:
86 return aidlEnumVal2Km<KeyParameterValue::ecCurve>(tag, param.value);
87 case KM_TAG_USER_AUTH_TYPE:
88 return aidlEnumVal2Km<KeyParameterValue::hardwareAuthenticatorType>(tag, param.value);
89 case KM_TAG_ORIGIN:
90 return aidlEnumVal2Km<KeyParameterValue::origin>(tag, param.value);
91 case KM_TAG_BLOB_USAGE_REQUIREMENTS:
92 case KM_TAG_KDF:
93 default:
94 CHECK(false) << "Unknown or unused enum tag: Something is broken";
95 return keymaster_param_enum(tag, false);
96 }
97 }
98
99 } // namespace
100
authToken2AidlVec(const std::optional<HardwareAuthToken> & token)101 vector<uint8_t> authToken2AidlVec(const std::optional<HardwareAuthToken>& token) {
102 static_assert(1 /* version size */ + sizeof(token->challenge) + sizeof(token->userId) +
103 sizeof(token->authenticatorId) + sizeof(token->authenticatorType) +
104 sizeof(token->timestamp) + 32 /* HMAC size */
105 == sizeof(hw_auth_token_t),
106 "HardwareAuthToken content size does not match hw_auth_token_t size");
107
108 vector<uint8_t> result;
109
110 if (!token.has_value()) return result;
111 if (token->mac.size() < 32) return result;
112
113 result.resize(sizeof(hw_auth_token_t));
114 auto pos = result.begin();
115 *pos++ = 0; // Version byte
116 pos = copy_bytes_to_iterator(token->challenge, pos);
117 pos = copy_bytes_to_iterator(token->userId, pos);
118 pos = copy_bytes_to_iterator(token->authenticatorId, pos);
119 pos = copy_bytes_to_iterator(hton(static_cast<uint32_t>(token->authenticatorType)), pos);
120 pos = copy_bytes_to_iterator(hton(token->timestamp.milliSeconds), pos);
121 pos = std::copy(token->mac.data(), token->mac.data() + token->mac.size(), pos);
122
123 return result;
124 }
125
kmParam2Aidl(const keymaster_key_param_t & param)126 KeyParameter kmParam2Aidl(const keymaster_key_param_t& param) {
127 auto tag = legacy_enum_conversion(param.tag);
128 switch (typeFromTag(param.tag)) {
129 case KM_ENUM:
130 case KM_ENUM_REP:
131 return kmEnumParam2Aidl(param);
132 break;
133
134 case KM_UINT:
135 case KM_UINT_REP:
136 return KeyParameter{tag,
137 KeyParameterValue::make<KeyParameterValue::integer>(param.integer)};
138
139 case KM_ULONG:
140 case KM_ULONG_REP:
141 return KeyParameter{
142 tag, KeyParameterValue::make<KeyParameterValue::longInteger>(param.long_integer)};
143 break;
144
145 case KM_DATE:
146 return KeyParameter{tag,
147 KeyParameterValue::make<KeyParameterValue::dateTime>(param.date_time)};
148 break;
149
150 case KM_BOOL:
151 return KeyParameter{tag, param.boolean};
152 break;
153
154 case KM_BIGNUM:
155 case KM_BYTES:
156 return {tag, KeyParameterValue::make<KeyParameterValue::blob>(
157 std::vector(param.blob.data, param.blob.data + param.blob.data_length))};
158 break;
159
160 case KM_INVALID:
161 default:
162 CHECK(false) << "Unknown or unused tag type: Something is broken";
163 return KeyParameter{Tag::INVALID, false};
164 break;
165 }
166 }
167
kmParamSet2Aidl(const keymaster_key_param_set_t & set)168 vector<KeyParameter> kmParamSet2Aidl(const keymaster_key_param_set_t& set) {
169 vector<KeyParameter> result;
170 if (set.length == 0 || set.params == nullptr) return result;
171
172 result.reserve(set.length);
173 for (size_t i = 0; i < set.length; ++i) {
174 result.push_back(kmParam2Aidl(set.params[i]));
175 }
176 return result;
177 }
178
aidlKeyParams2Km(const vector<KeyParameter> & keyParams)179 keymaster_key_param_set_t aidlKeyParams2Km(const vector<KeyParameter>& keyParams) {
180 keymaster_key_param_set_t set;
181
182 set.params = static_cast<keymaster_key_param_t*>(
183 malloc(keyParams.size() * sizeof(keymaster_key_param_t)));
184 set.length = keyParams.size();
185
186 for (size_t i = 0; i < keyParams.size(); ++i) {
187 const auto& param = keyParams[i];
188 auto tag = legacy_enum_conversion(param.tag);
189 switch (typeFromTag(tag)) {
190
191 case KM_ENUM:
192 case KM_ENUM_REP:
193 set.params[i] = aidlEnumParam2Km(param);
194 break;
195
196 case KM_UINT:
197 case KM_UINT_REP:
198 set.params[i] =
199 param.value.getTag() == KeyParameterValue::integer
200 ? keymaster_param_int(tag, param.value.get<KeyParameterValue::integer>())
201 : kInvalidTag;
202 break;
203
204 case KM_ULONG:
205 case KM_ULONG_REP:
206 set.params[i] =
207 param.value.getTag() == KeyParameterValue::longInteger
208 ? keymaster_param_long(tag, param.value.get<KeyParameterValue::longInteger>())
209 : kInvalidTag;
210 break;
211
212 case KM_DATE:
213 set.params[i] =
214 param.value.getTag() == KeyParameterValue::dateTime
215 ? keymaster_param_date(tag, param.value.get<KeyParameterValue::dateTime>())
216 : kInvalidTag;
217 break;
218
219 case KM_BOOL:
220 set.params[i] = keymaster_param_bool(tag);
221 break;
222
223 case KM_BIGNUM:
224 case KM_BYTES:
225 if (param.value.getTag() == KeyParameterValue::blob) {
226 const auto& value = param.value.get<KeyParameterValue::blob>();
227 uint8_t* copy = static_cast<uint8_t*>(malloc(value.size()));
228 std::copy(value.begin(), value.end(), copy);
229 set.params[i] = keymaster_param_blob(tag, copy, value.size());
230 } else {
231 set.params[i] = kInvalidTag;
232 }
233 break;
234
235 case KM_INVALID:
236 default:
237 CHECK(false) << "Invalid tag: Something is broken";
238 set.params[i].tag = KM_TAG_INVALID;
239 /* just skip */
240 break;
241 }
242 }
243
244 return set;
245 }
246
247 } // namespace aidl::android::hardware::security::keymint::km_utils
248