From 88abd6c49ee7fb6aefb08ea36f2cda49955c5eda Mon Sep 17 00:00:00 2001 From: Laurentiu Nicola Date: Tue, 7 Jan 2014 20:26:50 +0200 Subject: [PATCH] rtp-recv: Only try adding the group membership for multicast addresses --- src/modules/rtp/module-rtp-recv.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) diff --git a/src/modules/rtp/module-rtp-recv.c b/src/modules/rtp/module-rtp-recv.c index 41b18ab0..9dc2febe 100644 --- a/src/modules/rtp/module-rtp-recv.c +++ b/src/modules/rtp/module-rtp-recv.c @@ -450,17 +450,26 @@ static int mcast_socket(const struct sockaddr* sa, socklen_t salen) { goto fail; } + r = 0; if (af == AF_INET) { - struct ip_mreq mr4; - memset(&mr4, 0, sizeof(mr4)); - mr4.imr_multiaddr = ((const struct sockaddr_in*) sa)->sin_addr; - r = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mr4, sizeof(mr4)); + /* IPv4 multicast addresses are in the 224.0.0.0-239.255.255.255 range */ + static const uint32_t ipv4_mcast_mask = 0xe0000000; + + if ((ntohl(((const struct sockaddr_in*) sa)->sin_addr.s_addr) & ipv4_mcast_mask) == ipv4_mcast_mask) { + struct ip_mreq mr4; + memset(&mr4, 0, sizeof(mr4)); + mr4.imr_multiaddr = ((const struct sockaddr_in*) sa)->sin_addr; + r = setsockopt(fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mr4, sizeof(mr4)); + } #ifdef HAVE_IPV6 } else if (af == AF_INET6) { - struct ipv6_mreq mr6; - memset(&mr6, 0, sizeof(mr6)); - mr6.ipv6mr_multiaddr = ((const struct sockaddr_in6*) sa)->sin6_addr; - r = setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mr6, sizeof(mr6)); + /* IPv6 multicast addresses have 255 as the most significant byte */ + if (((const struct sockaddr_in6*) sa)->sin6_addr.s6_addr[0] == 0xff) { + struct ipv6_mreq mr6; + memset(&mr6, 0, sizeof(mr6)); + mr6.ipv6mr_multiaddr = ((const struct sockaddr_in6*) sa)->sin6_addr; + r = setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mr6, sizeof(mr6)); + } #endif } else pa_assert_not_reached(); -- 2.39.2