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. */ |
30 | extern int __get_sol (int af, socklen_t len); |
31 | |
32 | |
33 | int |
34 | setsourcefilter (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 | |