1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2
3 #include <errno.h>
4 #include <netinet/in.h>
5 #include <stdbool.h>
6 #include <stddef.h>
7 #include <string.h>
8 #include <sys/un.h>
9 #include <unistd.h>
10
11 #include "alloc-util.h"
12 #include "fd-util.h"
13 #include "fs-util.h"
14 #include "log.h"
15 #include "macro.h"
16 #include "missing_socket.h"
17 #include "mkdir-label.h"
18 #include "selinux-util.h"
19 #include "socket-util.h"
20 #include "umask-util.h"
21
socket_address_listen(const SocketAddress * a,int flags,int backlog,SocketAddressBindIPv6Only only,const char * bind_to_device,bool reuse_port,bool free_bind,bool transparent,mode_t directory_mode,mode_t socket_mode,const char * label)22 int socket_address_listen(
23 const SocketAddress *a,
24 int flags,
25 int backlog,
26 SocketAddressBindIPv6Only only,
27 const char *bind_to_device,
28 bool reuse_port,
29 bool free_bind,
30 bool transparent,
31 mode_t directory_mode,
32 mode_t socket_mode,
33 const char *label) {
34
35 _cleanup_close_ int fd = -1;
36 const char *p;
37 int r;
38
39 assert(a);
40
41 r = socket_address_verify(a, true);
42 if (r < 0)
43 return r;
44
45 if (socket_address_family(a) == AF_INET6 && !socket_ipv6_is_supported())
46 return -EAFNOSUPPORT;
47
48 if (label) {
49 r = mac_selinux_create_socket_prepare(label);
50 if (r < 0)
51 return r;
52 }
53
54 fd = RET_NERRNO(socket(socket_address_family(a), a->type | flags, a->protocol));
55
56 if (label)
57 mac_selinux_create_socket_clear();
58
59 if (fd < 0)
60 return fd;
61
62 if (socket_address_family(a) == AF_INET6 && only != SOCKET_ADDRESS_DEFAULT) {
63 r = setsockopt_int(fd, IPPROTO_IPV6, IPV6_V6ONLY, only == SOCKET_ADDRESS_IPV6_ONLY);
64 if (r < 0)
65 return r;
66 }
67
68 if (IN_SET(socket_address_family(a), AF_INET, AF_INET6)) {
69 if (bind_to_device) {
70 r = socket_bind_to_ifname(fd, bind_to_device);
71 if (r < 0)
72 return r;
73 }
74
75 if (reuse_port) {
76 r = setsockopt_int(fd, SOL_SOCKET, SO_REUSEPORT, true);
77 if (r < 0)
78 log_warning_errno(r, "SO_REUSEPORT failed: %m");
79 }
80
81 if (free_bind) {
82 r = socket_set_freebind(fd, socket_address_family(a), true);
83 if (r < 0)
84 log_warning_errno(r, "IP_FREEBIND/IPV6_FREEBIND failed: %m");
85 }
86
87 if (transparent) {
88 r = socket_set_transparent(fd, socket_address_family(a), true);
89 if (r < 0)
90 log_warning_errno(r, "IP_TRANSPARENT/IPV6_TRANSPARENT failed: %m");
91 }
92 }
93
94 r = setsockopt_int(fd, SOL_SOCKET, SO_REUSEADDR, true);
95 if (r < 0)
96 return r;
97
98 p = socket_address_get_path(a);
99 if (p) {
100 /* Create parents */
101 (void) mkdir_parents_label(p, directory_mode);
102
103 /* Enforce the right access mode for the socket */
104 RUN_WITH_UMASK(~socket_mode) {
105 r = mac_selinux_bind(fd, &a->sockaddr.sa, a->size);
106 if (r == -EADDRINUSE) {
107 /* Unlink and try again */
108
109 if (unlink(p) < 0)
110 return r; /* didn't work, return original error */
111
112 r = mac_selinux_bind(fd, &a->sockaddr.sa, a->size);
113 }
114 if (r < 0)
115 return r;
116 }
117 } else {
118 if (bind(fd, &a->sockaddr.sa, a->size) < 0)
119 return -errno;
120 }
121
122 if (socket_address_can_accept(a))
123 if (listen(fd, backlog) < 0)
124 return -errno;
125
126 /* Let's trigger an inotify event on the socket node, so that anyone waiting for this socket to be connectable
127 * gets notified */
128 if (p)
129 (void) touch(p);
130
131 return TAKE_FD(fd);
132 }
133