1 /*
2 * Copyright (C) 2019 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 <android-base/file.h>
18 #include <android-base/logging.h>
19 #include <android-base/unique_fd.h>
20
21 #include "HadamardUtils.h"
22 #include "rebootescrow-impl/RebootEscrow.h"
23
24 namespace aidl {
25 namespace android {
26 namespace hardware {
27 namespace rebootescrow {
28
29 using ::android::base::unique_fd;
30
storeKey(const std::vector<int8_t> & kek)31 ndk::ScopedAStatus RebootEscrow::storeKey(const std::vector<int8_t>& kek) {
32 int rawFd = TEMP_FAILURE_RETRY(::open(devicePath_.c_str(), O_WRONLY | O_NOFOLLOW | O_CLOEXEC));
33 unique_fd fd(rawFd);
34 if (fd.get() < 0) {
35 LOG(WARNING) << "Could not open reboot escrow device";
36 return ndk::ScopedAStatus(AStatus_fromExceptionCode(EX_UNSUPPORTED_OPERATION));
37 }
38
39 std::vector<uint8_t> ukek(kek.begin(), kek.end());
40 auto encoded = hadamard::EncodeKey(ukek);
41
42 if (!::android::base::WriteFully(fd, encoded.data(), encoded.size())) {
43 LOG(WARNING) << "Could not write data fully to character device";
44 return ndk::ScopedAStatus(AStatus_fromExceptionCode(EX_UNSUPPORTED_OPERATION));
45 }
46
47 return ndk::ScopedAStatus::ok();
48 }
49
retrieveKey(std::vector<int8_t> * _aidl_return)50 ndk::ScopedAStatus RebootEscrow::retrieveKey(std::vector<int8_t>* _aidl_return) {
51 int rawFd = TEMP_FAILURE_RETRY(::open(devicePath_.c_str(), O_RDONLY | O_NOFOLLOW | O_CLOEXEC));
52 unique_fd fd(rawFd);
53 if (fd.get() < 0) {
54 LOG(WARNING) << "Could not open reboot escrow device";
55 return ndk::ScopedAStatus(AStatus_fromExceptionCode(EX_UNSUPPORTED_OPERATION));
56 }
57
58 std::vector<uint8_t> encodedBytes(hadamard::OUTPUT_SIZE_BYTES);
59 if (!::android::base::ReadFully(fd, &encodedBytes[0], encodedBytes.size())) {
60 LOG(WARNING) << "Could not read device";
61 return ndk::ScopedAStatus(AStatus_fromExceptionCode(EX_UNSUPPORTED_OPERATION));
62 }
63
64 auto keyBytes = hadamard::DecodeKey(encodedBytes);
65
66 std::vector<int8_t> signedKeyBytes(keyBytes.begin(), keyBytes.end());
67 *_aidl_return = signedKeyBytes;
68 return ndk::ScopedAStatus::ok();
69 }
70
71 } // namespace rebootescrow
72 } // namespace hardware
73 } // namespace android
74 } // namespace aidl
75