1 /* Find network interface names and index numbers. Hurd version.
2 Copyright (C) 2000-2023 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #include <error.h>
20 #include <net/if.h>
21 #include <string.h>
22 #include <sys/ioctl.h>
23 #include <unistd.h>
24
25 #include <hurd.h>
26 #include <hurd/ioctl.h>
27 #include <hurd/pfinet.h>
28
29 /* Return the interface index corresponding to interface IFNAME.
30 On error, return 0. */
31 unsigned int
32 __if_nametoindex (const char *ifname)
33 {
34 struct ifreq ifr;
35 int fd = __socket (AF_INET, SOCK_DGRAM, 0);
36
37 if (fd < 0)
38 return 0;
39
40 if (strlen (ifname) >= IFNAMSIZ)
41 return __hurd_fail (ENODEV), 0;
42
43 strncpy (ifr.ifr_name, ifname, IFNAMSIZ);
44 if (__ioctl (fd, SIOCGIFINDEX, &ifr) < 0)
45 {
46 int saved_errno = errno;
47 __close (fd);
48 if (saved_errno == EINVAL || saved_errno == ENOTTY)
49 __hurd_fail (ENOSYS);
50 return 0;
51 }
52 __close (fd);
53 return ifr.ifr_ifindex;
54 }
55 libc_hidden_def (__if_nametoindex)
56 weak_alias (__if_nametoindex, if_nametoindex)
57 libc_hidden_weak (if_nametoindex)
58
59 /* Free the structure IFN returned by if_nameindex. */
60 void
61 __if_freenameindex (struct if_nameindex *ifn)
62 {
63 struct if_nameindex *ptr = ifn;
64 while (ptr->if_name || ptr->if_index)
65 {
66 free (ptr->if_name);
67 ++ptr;
68 }
69 free (ifn);
70 }
71 libc_hidden_def (__if_freenameindex)
72 weak_alias (__if_freenameindex, if_freenameindex)
73 libc_hidden_weak (if_freenameindex)
74
75 /* Return an array of if_nameindex structures, one for each network
76 interface present, plus one indicating the end of the array. On
77 error, return NULL. */
78 struct if_nameindex *
79 __if_nameindex (void)
80 {
81 error_t err = 0;
82 char data[2048];
83 file_t server;
84 int fd = __socket (AF_INET, SOCK_DGRAM, 0);
85 struct ifconf ifc;
86 unsigned int nifs, i;
87 struct if_nameindex *idx = NULL;
88
89 ifc.ifc_buf = data;
90
91 if (fd < 0)
92 return NULL;
93
94 server = _hurd_socket_server (PF_INET, 0);
95 if (server == MACH_PORT_NULL)
96 nifs = 0;
97 else
98 {
99 mach_msg_type_number_t len = sizeof data;
100 err = __pfinet_siocgifconf (server, -1, &ifc.ifc_buf, &len);
101 if (err == MACH_SEND_INVALID_DEST || err == MIG_SERVER_DIED)
102 {
103 /* On the first use of the socket server during the operation,
104 allow for the old server port dying. */
105 server = _hurd_socket_server (PF_INET, 1);
106 if (server == MACH_PORT_NULL)
107 goto out;
108 err = __pfinet_siocgifconf (server, -1, &ifc.ifc_buf, &len);
109 }
110 if (err)
111 goto out;
112
113 ifc.ifc_len = len;
114 nifs = len / sizeof (struct ifreq);
115 }
116
117 idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
118 if (idx == NULL)
119 {
120 err = ENOBUFS;
121 goto out;
122 }
123
124 for (i = 0; i < nifs; ++i)
125 {
126 struct ifreq *ifr = &ifc.ifc_req[i];
127 idx[i].if_name = __strdup (ifr->ifr_name);
128 if (idx[i].if_name == NULL
129 || __ioctl (fd, SIOCGIFINDEX, ifr) < 0)
130 {
131 unsigned int j;
132 err = errno;
133
134 for (j = 0; j < i; ++j)
135 free (idx[j].if_name);
136 free (idx);
137 idx = NULL;
138
139 if (err == EINVAL)
140 err = ENOSYS;
141 else if (err == ENOMEM)
142 err = ENOBUFS;
143 goto out;
144 }
145 idx[i].if_index = ifr->ifr_ifindex;
146 }
147
148 idx[i].if_index = 0;
149 idx[i].if_name = NULL;
150
151 out:
152 __close (fd);
153 if (data != ifc.ifc_buf)
154 __vm_deallocate (__mach_task_self (), (vm_address_t) ifc.ifc_buf,
155 ifc.ifc_len);
156 __set_errno (err);
157 return idx;
158 }
159 weak_alias (__if_nameindex, if_nameindex)
160 libc_hidden_weak (if_nameindex)
161
162 /* Store the name of the interface corresponding to index IFINDEX in
163 IFNAME (which has space for at least IFNAMSIZ characters). Return
164 IFNAME, or NULL on error. */
165 char *
166 __if_indextoname (unsigned int ifindex, char ifname[IF_NAMESIZE])
167 {
168 struct ifreq ifr;
169 int fd = __socket (AF_INET, SOCK_DGRAM, 0);
170
171 if (fd < 0)
172 return NULL;
173
174 ifr.ifr_ifindex = ifindex;
175 if (__ioctl (fd, SIOCGIFNAME, &ifr) < 0)
176 {
177 int saved_errno = errno;
178 __close (fd);
179 if (saved_errno == EINVAL || saved_errno == ENOTTY)
180 __hurd_fail (ENOSYS);
181 else if (saved_errno == ENODEV)
182 __hurd_fail (ENXIO);
183 return NULL;
184 }
185 __close (fd);
186 return strncpy (ifname, ifr.ifr_name, IFNAMSIZ);
187 }
188 weak_alias (__if_indextoname, if_indextoname)
189 libc_hidden_weak (if_indextoname)
190
191 #if 0
192 void
193 __protocol_available (int *have_inet, int *have_inet6)
194 {
195 *have_inet = _hurd_socket_server (PF_INET, 0) != MACH_PORT_NULL;
196 *have_inet6 = _hurd_socket_server (PF_INET6, 0) != MACH_PORT_NULL;
197 }
198 #endif