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/*
* BIRD Internet Routing Daemon -- NetBSD Multicasting and Network Includes
*
* (c) 2004 Ondrej Filip <feela@network.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifdef IPV6
static inline void
set_inaddr(struct in6_addr * ia, ip_addr a)
{
ipa_hton(a);
memcpy(ia, &a, sizeof(a));
}
#else
#include <net/if.h>
static inline void
set_inaddr(struct in_addr * ia, ip_addr a)
{
ipa_hton(a);
memcpy(&ia->s_addr, &a, sizeof(a));
}
static inline char *
sysio_mcast_setup(sock * s)
{
u8 zero = 0;
u8 one = 1;
if (ipa_nonzero(s->daddr)) {
if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &zero, sizeof(zero)) < 0)
return "IP_MULTICAST_LOOP";
if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_TTL, &one, sizeof(one)) < 0)
return "IP_MULTICAST_TTL";
}
return NULL;
}
static inline char *
sysio_mcast_join(sock * s)
{
struct in_addr m;
struct ip_mreq mreq;
char *err;
set_inaddr(&m, s->iface->addr->ip );
bzero(&mreq, sizeof(mreq));
set_inaddr(&mreq.imr_interface, s->iface->addr->ip);
set_inaddr(&mreq.imr_multiaddr, s->daddr);
/* And this one sets interface for _receiving_ multicasts from */
if (ipa_nonzero(s->daddr) &&
setsockopt(s->fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
return "IP_ADD_MEMBERSHIP";
/* This defines where should we send _outgoing_ multicasts */
if (ipa_nonzero(s->daddr) && setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_IF, &m, sizeof(m)) < 0)
return "IP_MULTICAST_IF";
if (err = sysio_mcast_setup(s))
return err;
return NULL;
}
#endif
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