1/* Set source filter. Linux version.
2 Copyright (C) 2004-2024 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 <errno.h>
20#include <string.h>
21#include <netinet/in.h>
22#include <scratch_buffer.h>
23#include "getsourcefilter.h"
24
25
26int
27setsourcefilter (int s, uint32_t interface, const struct sockaddr *group,
28 socklen_t grouplen, uint32_t fmode, uint32_t numsrc,
29 const struct sockaddr_storage *slist)
30{
31 /* We have to create an struct ip_msfilter object which we can pass
32 to the kernel. */
33 size_t needed = GROUP_FILTER_SIZE (numsrc);
34
35 struct scratch_buffer buf;
36 scratch_buffer_init (buffer: &buf);
37 if (!scratch_buffer_set_array_size (buffer: &buf, nelem: 1, size: needed))
38 return -1;
39 struct group_filter *gf = buf.data;
40
41 gf->gf_interface = interface;
42 memcpy (&gf->gf_group, group, grouplen);
43 gf->gf_fmode = fmode;
44 gf->gf_numsrc = numsrc;
45 memcpy (gf->gf_slist, slist, numsrc * sizeof (struct sockaddr_storage));
46
47 /* We need to provide the appropriate socket level value. */
48 int result;
49 int sol = __get_sol (af: group->sa_family, len: grouplen);
50 if (sol == -1)
51 {
52 __set_errno (EINVAL);
53 result = -1;
54 }
55 else
56 result = __setsockopt (s, sol, MCAST_MSFILTER, gf, needed);
57
58 scratch_buffer_free (buffer: &buf);
59
60 return result;
61}
62

source code of glibc/sysdeps/unix/sysv/linux/setsourcefilter.c