jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2022, sin-ack <sin-ack@protonmail.com>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include "SystemServerTakeover.h"
8#include <LibCore/Socket.h>
9#include <LibCore/System.h>
10
11namespace Core {
12
13HashMap<DeprecatedString, int> s_overtaken_sockets {};
14bool s_overtaken_sockets_parsed { false };
15
16static void parse_sockets_from_system_server()
17{
18 VERIFY(!s_overtaken_sockets_parsed);
19
20 constexpr auto socket_takeover = "SOCKET_TAKEOVER";
21 char const* sockets = getenv(socket_takeover);
22 if (!sockets) {
23 s_overtaken_sockets_parsed = true;
24 return;
25 }
26
27 for (auto const socket : StringView { sockets, strlen(sockets) }.split_view(';')) {
28 auto params = socket.split_view(':');
29 s_overtaken_sockets.set(params[0].to_deprecated_string(), strtol(params[1].to_deprecated_string().characters(), nullptr, 10));
30 }
31
32 s_overtaken_sockets_parsed = true;
33 // We wouldn't want our children to think we're passing
34 // them a socket either, so unset the env variable.
35 unsetenv(socket_takeover);
36}
37
38ErrorOr<NonnullOwnPtr<Core::LocalSocket>> take_over_socket_from_system_server(DeprecatedString const& socket_path)
39{
40 if (!s_overtaken_sockets_parsed)
41 parse_sockets_from_system_server();
42
43 int fd;
44 if (socket_path.is_null()) {
45 // We want the first (and only) socket.
46 VERIFY(s_overtaken_sockets.size() == 1);
47 fd = s_overtaken_sockets.begin()->value;
48 } else {
49 auto it = s_overtaken_sockets.find(socket_path);
50 if (it == s_overtaken_sockets.end())
51 return Error::from_string_literal("Non-existent socket requested");
52 fd = it->value;
53 }
54
55 // Sanity check: it has to be a socket.
56 auto stat = TRY(Core::System::fstat(fd));
57
58 if (!S_ISSOCK(stat.st_mode))
59 return Error::from_string_literal("The fd we got from SystemServer is not a socket");
60
61 auto socket = TRY(Core::LocalSocket::adopt_fd(fd));
62 // It had to be !CLOEXEC for obvious reasons, but we
63 // don't need it to be !CLOEXEC anymore, so set the
64 // CLOEXEC flag now.
65 TRY(socket->set_close_on_exec(true));
66
67 return socket;
68}
69
70}