1 /*
2 * Copyright 2022 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 "common/libs/security/confui_sign.h"
18
19 #include <android-base/logging.h>
20
21 #include "common/libs/fs/shared_buf.h"
22
23 namespace cuttlefish {
Send(SharedFD output,const confui::SignMessageError error,const std::vector<std::uint8_t> & payload)24 bool ConfUiSignerImpl::Send(SharedFD output,
25 const confui::SignMessageError error,
26 const std::vector<std::uint8_t>& payload) {
27 #define SET_FLAG_AND_RETURN_SEND \
28 sign_status_ |= kIoError; \
29 return false
30
31 // this looks redudant but makes sure that the byte-length of
32 // the error is guaranteed to be the same when it is received
33 confui::SignRawMessage msg;
34 msg.error_ = error;
35 auto n_written_err = WriteAllBinary(output, &(msg.error_));
36 if (n_written_err != sizeof(msg.error_)) {
37 sign_status_ |= kIoError;
38 SET_FLAG_AND_RETURN_SEND;
39 }
40 decltype(msg.payload_.size()) payload_size = payload.size();
41 auto n_written_payload_size = WriteAllBinary(output, &payload_size);
42 if (n_written_payload_size != sizeof(payload_size)) {
43 SET_FLAG_AND_RETURN_SEND;
44 }
45 const char* buf = reinterpret_cast<const char*>(payload.data());
46 auto n_written_payload = WriteAll(output, buf, payload.size());
47
48 if (n_written_payload != payload.size()) {
49 SET_FLAG_AND_RETURN_SEND;
50 }
51 return true;
52 }
53
Receive(SharedFD input)54 std::optional<confui::SignRawMessage> ConfUiSignerImpl::Receive(
55 SharedFD input) {
56 confui::SignRawMessage msg;
57
58 auto n_read = ReadExactBinary(input, &(msg.error_));
59 if (n_read != sizeof(msg.error_)) {
60 sign_status_ |= kIoError;
61 }
62 if (msg.error_ != confui::SignMessageError::kOk) {
63 sign_status_ |= kLogicError;
64 }
65 if (!IsOk()) {
66 return std::nullopt;
67 }
68
69 decltype(msg.payload_.size()) payload_size = 0;
70 n_read = ReadExactBinary(input, &payload_size);
71 if (n_read != sizeof(payload_size)) {
72 sign_status_ |= kIoError;
73 return std::nullopt;
74 }
75
76 std::vector<std::uint8_t> buffer(payload_size);
77 char* buf_data = reinterpret_cast<char*>(buffer.data());
78 n_read = ReadExact(input, buf_data, payload_size);
79 if (n_read != payload_size) {
80 sign_status_ |= kIoError;
81 return std::nullopt;
82 }
83 msg.payload_.swap(buffer);
84 return {msg};
85 }
86
Receive()87 std::optional<confui::SignRawMessage> ConfUiSignSender::Receive() {
88 return impl_.Receive(server_fd_);
89 }
90
Send(const SignMessageError error,const std::vector<std::uint8_t> & encoded_hmac)91 bool ConfUiSignSender::Send(const SignMessageError error,
92 const std::vector<std::uint8_t>& encoded_hmac) {
93 if (!impl_.IsOk()) {
94 return false;
95 }
96 impl_.Send(server_fd_, error, encoded_hmac);
97 return impl_.IsOk();
98 }
99
Request(const std::vector<std::uint8_t> & message)100 bool ConfUiSignRequester::Request(const std::vector<std::uint8_t>& message) {
101 impl_.Send(client_fd_, confui::SignMessageError::kOk, message);
102 return impl_.IsOk();
103 }
104
Receive()105 std::optional<confui::SignRawMessage> ConfUiSignRequester::Receive() {
106 if (!impl_.IsOk()) {
107 return std::nullopt;
108 }
109 return impl_.Receive(client_fd_);
110 }
111 } // namespace cuttlefish
112