1/*
2 * systemd socket activation support
3 *
4 * Copyright 2017 Red Hat, Inc. and/or its affiliates
5 *
6 * Authors:
7 * Richard W.M. Jones <rjones@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 */
12
13#include "qemu/osdep.h"
14#include "qemu/systemd.h"
15#include "qemu/cutils.h"
16#include "qemu/error-report.h"
17
18#ifndef _WIN32
19unsigned int check_socket_activation(void)
20{
21 const char *s;
22 unsigned long pid;
23 unsigned long nr_fds;
24 unsigned int i;
25 int fd;
26 int err;
27
28 s = getenv("LISTEN_PID");
29 if (s == NULL) {
30 return 0;
31 }
32 err = qemu_strtoul(s, NULL, 10, &pid);
33 if (err) {
34 return 0;
35 }
36 if (pid != getpid()) {
37 return 0;
38 }
39
40 s = getenv("LISTEN_FDS");
41 if (s == NULL) {
42 return 0;
43 }
44 err = qemu_strtoul(s, NULL, 10, &nr_fds);
45 if (err) {
46 return 0;
47 }
48 assert(nr_fds <= UINT_MAX);
49
50 /* So these are not passed to any child processes we might start. */
51 unsetenv("LISTEN_FDS");
52 unsetenv("LISTEN_PID");
53
54 /* So the file descriptors don't leak into child processes. */
55 for (i = 0; i < nr_fds; ++i) {
56 fd = FIRST_SOCKET_ACTIVATION_FD + i;
57 if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1) {
58 /* If we cannot set FD_CLOEXEC then it probably means the file
59 * descriptor is invalid, so socket activation has gone wrong
60 * and we should exit.
61 */
62 error_report("Socket activation failed: "
63 "invalid file descriptor fd = %d: %m",
64 fd);
65 exit(EXIT_FAILURE);
66 }
67 }
68
69 return (unsigned int) nr_fds;
70}
71
72#else /* !_WIN32 */
73unsigned int check_socket_activation(void)
74{
75 return 0;
76}
77#endif
78