1 /*
2 * Copyright (C) 2021 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 "RpcRawTransport"
18 #include <log/log.h>
19
20 #include <poll.h>
21 #include <stddef.h>
22 #include <sys/socket.h>
23
24 #include <binder/RpcTransportRaw.h>
25
26 #include "FdTrigger.h"
27 #include "OS.h"
28 #include "RpcState.h"
29 #include "RpcTransportUtils.h"
30
31 namespace android {
32
33 using namespace android::binder::impl;
34 using android::binder::borrowed_fd;
35 using android::binder::unique_fd;
36
37 // RpcTransport with TLS disabled.
38 class RpcTransportRaw : public RpcTransport {
39 public:
RpcTransportRaw(android::RpcTransportFd socket)40 explicit RpcTransportRaw(android::RpcTransportFd socket) : mSocket(std::move(socket)) {}
pollRead(void)41 status_t pollRead(void) override {
42 uint8_t buf;
43 ssize_t ret = TEMP_FAILURE_RETRY(
44 ::recv(mSocket.fd.get(), &buf, sizeof(buf), MSG_PEEK | MSG_DONTWAIT));
45 if (ret < 0) {
46 int savedErrno = errno;
47 if (savedErrno == EAGAIN || savedErrno == EWOULDBLOCK) {
48 return WOULD_BLOCK;
49 }
50
51 LOG_RPC_DETAIL("RpcTransport poll(): %s", strerror(savedErrno));
52 return -savedErrno;
53 } else if (ret == 0) {
54 return DEAD_OBJECT;
55 }
56
57 return OK;
58 }
59
interruptableWriteFully(FdTrigger * fdTrigger,iovec * iovs,int niovs,const std::optional<SmallFunction<status_t ()>> & altPoll,const std::vector<std::variant<unique_fd,borrowed_fd>> * ancillaryFds)60 status_t interruptableWriteFully(
61 FdTrigger* fdTrigger, iovec* iovs, int niovs,
62 const std::optional<SmallFunction<status_t()>>& altPoll,
63 const std::vector<std::variant<unique_fd, borrowed_fd>>* ancillaryFds) override {
64 bool sentFds = false;
65 auto send = [&](iovec* iovs, int niovs) -> ssize_t {
66 ssize_t ret = binder::os::sendMessageOnSocket(mSocket, iovs, niovs,
67 sentFds ? nullptr : ancillaryFds);
68 sentFds |= ret > 0;
69 return ret;
70 };
71 return interruptableReadOrWrite(mSocket, fdTrigger, iovs, niovs, send, "sendmsg", POLLOUT,
72 altPoll);
73 }
74
interruptableReadFully(FdTrigger * fdTrigger,iovec * iovs,int niovs,const std::optional<SmallFunction<status_t ()>> & altPoll,std::vector<std::variant<unique_fd,borrowed_fd>> * ancillaryFds)75 status_t interruptableReadFully(
76 FdTrigger* fdTrigger, iovec* iovs, int niovs,
77 const std::optional<SmallFunction<status_t()>>& altPoll,
78 std::vector<std::variant<unique_fd, borrowed_fd>>* ancillaryFds) override {
79 auto recv = [&](iovec* iovs, int niovs) -> ssize_t {
80 return binder::os::receiveMessageFromSocket(mSocket, iovs, niovs, ancillaryFds);
81 };
82 return interruptableReadOrWrite(mSocket, fdTrigger, iovs, niovs, recv, "recvmsg", POLLIN,
83 altPoll);
84 }
85
isWaiting()86 bool isWaiting() override { return mSocket.isInPollingState(); }
87
88 private:
89 android::RpcTransportFd mSocket;
90 };
91
92 // RpcTransportCtx with TLS disabled.
93 class RpcTransportCtxRaw : public RpcTransportCtx {
94 public:
newTransport(android::RpcTransportFd socket,FdTrigger *) const95 std::unique_ptr<RpcTransport> newTransport(android::RpcTransportFd socket,
96 FdTrigger*) const override {
97 return std::make_unique<RpcTransportRaw>(std::move(socket));
98 }
getCertificate(RpcCertificateFormat) const99 std::vector<uint8_t> getCertificate(RpcCertificateFormat) const override { return {}; }
100 };
101
newServerCtx() const102 std::unique_ptr<RpcTransportCtx> RpcTransportCtxFactoryRaw::newServerCtx() const {
103 return std::make_unique<RpcTransportCtxRaw>();
104 }
105
newClientCtx() const106 std::unique_ptr<RpcTransportCtx> RpcTransportCtxFactoryRaw::newClientCtx() const {
107 return std::make_unique<RpcTransportCtxRaw>();
108 }
109
toCString() const110 const char *RpcTransportCtxFactoryRaw::toCString() const {
111 return "raw";
112 }
113
make()114 std::unique_ptr<RpcTransportCtxFactory> RpcTransportCtxFactoryRaw::make() {
115 return std::unique_ptr<RpcTransportCtxFactoryRaw>(new RpcTransportCtxFactoryRaw());
116 }
117
118 } // namespace android
119