1 // Copyright 2022 Google LLC
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 //      http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #include <fmt/format.h>
16 
17 #include <sdeventplus/event.hpp>
18 #include <sdeventplus/source/io.hpp>
19 #include <stdplus/fd/create.hpp>
20 #include <stdplus/fd/ops.hpp>
21 
22 using namespace std::string_view_literals;
23 
24 // A privileged port that is reserved for querying BMC DHCP completion.
25 // This is well known by the clients querying the status.
26 constexpr uint16_t kListenPort = 23;
27 enum : uint8_t
28 {
29     DONE = 0,
30     POWERCYCLE = 1,
31 };
32 
33 stdplus::ManagedFd createListener()
34 {
35     using namespace stdplus::fd;
36     auto sock = socket(SocketDomain::INet6, SocketType::Stream,
37                        SocketProto::TCP);
38     setFileFlags(sock, getFileFlags(sock).set(stdplus::fd::FileFlag::NonBlock));
39     sockaddr_in6 addr = {};
40     addr.sin6_family = AF_INET6;
41     addr.sin6_port = htons(kListenPort);
42     bind(sock, addr);
43     listen(sock, 10);
44     return sock;
45 }
46 
47 int main(int argc, char* argv[])
48 {
49     if (argc != 2)
50     {
51         fmt::print(stderr, "Invalid parameter count\n");
52         return 1;
53     }
54 
55     std::vector<uint8_t> data;
56 
57     if (argv[1] == "POWERCYCLE"sv)
58     {
59         data.push_back(POWERCYCLE);
60     }
61     else if (argv[1] == "DONE"sv)
62     {
63         data.push_back(DONE);
64     }
65     else
66     {
67         fmt::print(stderr, "Invalid parameter\n");
68         return 1;
69     }
70 
71     try
72     {
73         auto listener = createListener();
74         auto event = sdeventplus::Event::get_default();
75         sdeventplus::source::IO do_accept(
76             event, listener.get(), EPOLLIN | EPOLLET,
77             [&](sdeventplus::source::IO&, int, uint32_t) {
78             while (auto fd = stdplus::fd::accept(listener))
79             {
80                 stdplus::fd::sendExact(*fd, data, stdplus::fd::SendFlags(0));
81             }
82         });
83         return event.loop();
84     }
85     catch (const std::exception& e)
86     {
87         fmt::print(stderr, "Failed: {}\n", e.what());
88         return 1;
89     }
90 }
91