1/* Set source filter. Linux version.
2 Copyright (C) 2004-2017 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Ulrich Drepper <drepper@redhat.com>, 2004.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20#include <alloca.h>
21#include <errno.h>
22#include <stdlib.h>
23#include <string.h>
24#include <stdint.h>
25#include <netinet/in.h>
26#include <sys/socket.h>
27
28
29/* Defined in getsourcefilter.c. */
30extern int __get_sol (int af, socklen_t len);
31
32
33int
34setsourcefilter (int s, uint32_t interface, const struct sockaddr *group,
35 socklen_t grouplen, uint32_t fmode, uint32_t numsrc,
36 const struct sockaddr_storage *slist)
37{
38 /* We have to create an struct ip_msfilter object which we can pass
39 to the kernel. */
40 size_t needed = GROUP_FILTER_SIZE (numsrc);
41 int use_alloca = __libc_use_alloca (needed);
42
43 struct group_filter *gf;
44 if (use_alloca)
45 gf = (struct group_filter *) alloca (needed);
46 else
47 {
48 gf = (struct group_filter *) malloc (needed);
49 if (gf == NULL)
50 return -1;
51 }
52
53 gf->gf_interface = interface;
54 memcpy (&gf->gf_group, group, grouplen);
55 gf->gf_fmode = fmode;
56 gf->gf_numsrc = numsrc;
57 memcpy (gf->gf_slist, slist, numsrc * sizeof (struct sockaddr_storage));
58
59 /* We need to provide the appropriate socket level value. */
60 int result;
61 int sol = __get_sol (group->sa_family, grouplen);
62 if (sol == -1)
63 {
64 __set_errno (EINVAL);
65 result = -1;
66 }
67 else
68 result = __setsockopt (s, sol, MCAST_MSFILTER, gf, needed);
69
70 if (! use_alloca)
71 {
72 int save_errno = errno;
73 free (gf);
74 __set_errno (save_errno);
75 }
76
77 return result;
78}
79