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/logging.h>
18 #include <android-base/parseint.h>
19 #include <android-base/strings.h>
20 #include <android/hardware/automotive/can/1.0/ICanBus.h>
21 #include <android/hidl/manager/1.2/IServiceManager.h>
22
23 #include <iostream>
24 #include <string>
25
26 namespace android::hardware::automotive::can {
27
28 using ICanBus = V1_0::ICanBus;
29 using Result = V1_0::Result;
30
usage()31 static void usage() {
32 std::cerr << "canhalsend - simple command line tool to send raw CAN frames" << std::endl;
33 std::cerr << std::endl << "usage:" << std::endl << std::endl;
34 std::cerr << "canhalsend <bus name> <can id>#<data>" << std::endl;
35 std::cerr << "where:" << std::endl;
36 std::cerr << " bus name - name under which ICanBus is published" << std::endl;
37 std::cerr << " can id - such as 1a5 or 1fab5982" << std::endl;
38 std::cerr << " data - such as deadbeef, 010203, or R for a remote frame" << std::endl;
39 }
40
41 // TODO(b/135918744): extract to a new library
tryOpen(const std::string & busname)42 static sp<ICanBus> tryOpen(const std::string& busname) {
43 auto bus = ICanBus::tryGetService(busname);
44 if (bus != nullptr) return bus;
45
46 /* Fallback for interfaces not registered in manifest. For testing purposes only,
47 * one should not depend on this in production deployment. */
48 auto manager = hidl::manager::V1_2::IServiceManager::getService();
49 auto ret = manager->get(ICanBus::descriptor, busname).withDefault(nullptr);
50 if (ret == nullptr) return nullptr;
51
52 std::cerr << "WARNING: bus " << busname << " is not registered in device manifest, "
53 << "trying to fetch it directly..." << std::endl;
54
55 return ICanBus::castFrom(ret);
56 }
57
cansend(const std::string & busname,const V1_0::CanMessage & msg)58 static int cansend(const std::string& busname, const V1_0::CanMessage& msg) {
59 auto bus = tryOpen(busname);
60 if (bus == nullptr) {
61 std::cerr << "Bus " << busname << " is not available" << std::endl;
62 return -1;
63 }
64
65 const auto result = bus->send(msg);
66 if (result != Result::OK) {
67 std::cerr << "Send call failed: " << toString(result) << std::endl;
68 return -1;
69 }
70 return 0;
71 }
72
parseCanMessage(const std::string & msg)73 static std::optional<V1_0::CanMessage> parseCanMessage(const std::string& msg) {
74 const auto hashpos = msg.find("#");
75 if (hashpos == std::string::npos) return std::nullopt;
76
77 const std::string msgidStr = msg.substr(0, hashpos);
78 const std::string payloadStr = msg.substr(hashpos + 1);
79
80 V1_0::CanMessageId msgid;
81 // "0x" must be prepended to msgidStr, since ParseUint doesn't accept a base argument.
82 if (!android::base::ParseUint("0x" + msgidStr, &msgid)) return std::nullopt;
83
84 V1_0::CanMessage canmsg = {};
85 canmsg.id = msgid;
86 if (msgid > 0x7FF) {
87 canmsg.isExtendedId = true;
88 }
89
90 if (android::base::StartsWith(payloadStr, "R")) {
91 canmsg.remoteTransmissionRequest = true;
92
93 /* The CAN bus HAL doesn't define a data length code (DLC) field, since it is inferrred
94 * from the payload size. RTR messages indicate to the receiver how many bytes they are
95 * expecting to receive back via the DLC sent with the RTR frame. */
96 if (payloadStr.size() <= 1) return canmsg;
97
98 unsigned int dlc = 0;
99
100 /* The maximum DLC for CAN-FD is 64 bytes and CAN 2.0 is 8 bytes. Limit the size of the DLC
101 * to something memory safe and let the HAL determine if the DLC is valid. */
102 if (!android::base::ParseUint(payloadStr.substr(1), &dlc, 10000u)) {
103 std::cerr << "Invalid DLC for RTR frame!" << std::endl;
104 return std::nullopt;
105 }
106 canmsg.payload.resize(dlc);
107 return canmsg;
108 }
109
110 std::vector<uint8_t> payload;
111 if (payloadStr.size() % 2 != 0) return std::nullopt;
112 for (size_t i = 0; i < payloadStr.size(); i += 2) {
113 std::string byteStr(payloadStr, i, 2);
114 uint8_t byteBuf;
115 if (!android::base::ParseUint("0x" + byteStr, &byteBuf)) return std::nullopt;
116 payload.emplace_back(byteBuf);
117 }
118 canmsg.payload = payload;
119
120 return canmsg;
121 }
122
main(int argc,char * argv[])123 static int main(int argc, char* argv[]) {
124 base::SetDefaultTag("CanHalSend");
125 base::SetMinimumLogSeverity(android::base::VERBOSE);
126
127 if (argc == 0) {
128 usage();
129 return 0;
130 }
131
132 if (argc != 2) {
133 std::cerr << "Invalid number of arguments" << std::endl;
134 usage();
135 return -1;
136 }
137
138 std::string busname(argv[0]);
139 const auto canmsg = parseCanMessage(argv[1]);
140 if (!canmsg) {
141 std::cerr << "Failed to parse CAN message argument" << std::endl;
142 return -1;
143 }
144
145 return cansend(busname, *canmsg);
146 }
147
148 } // namespace android::hardware::automotive::can
149
main(int argc,char * argv[])150 int main(int argc, char* argv[]) {
151 if (argc < 1) return -1;
152 return ::android::hardware::automotive::can::main(--argc, ++argv);
153 }
154