diff options
| -rw-r--r-- | socket.c | 92 | ||||
| -rw-r--r-- | socket.h | 7 |
2 files changed, 89 insertions, 10 deletions
@@ -24,6 +24,7 @@ #include <arpa/inet.h> #include <linux/netlink.h> #include <linux/rtnetlink.h> +#include <net/if.h> #include <netinet/in.h> #include <sys/socket.h> #include <sys/types.h> @@ -35,11 +36,10 @@ static const int YES = 1; static const int NO = 0; -int socket_open_v4(uint16_t port) +int socket_open_ipv4(uint16_t port) { int sock; struct sockaddr_in sa; - struct ip_mreq mreq; sock = socket(AF_INET, SOCK_DGRAM, 0); if (sock < 0) { @@ -49,7 +49,7 @@ int socket_open_v4(uint16_t port) /* pass pktinfo struct on received packets */ if (setsockopt(sock, IPPROTO_IP, IP_PKTINFO, &YES, sizeof(YES)) < 0) { - log_err("Failed to set IP_PKTINFO option: %s\n", strerror(errno)); + log_err("Failed to set IPv4 packet info socket option: %s\n", strerror(errno)); goto err; } @@ -64,13 +64,41 @@ int socket_open_v4(uint16_t port) goto err; } - /* join the multicast group */ - memset(&mreq, 0, sizeof(mreq)); - mreq.imr_interface.s_addr = INADDR_ANY; - inet_pton(AF_INET, LLMNR_IPV4_MCAST_ADDR, &mreq.imr_multiaddr); + return sock; +err: + close(sock); + return -1; +} + +int socket_open_ipv6(uint16_t port) +{ + int sock, opt_pktinfo; + struct sockaddr_in6 sa; - if (setsockopt(sock, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0) { - log_err("Failed to join multicast group: %s\n", strerror(errno)); + sock = socket(AF_INET6, SOCK_DGRAM, 0); + if (sock < 0) { + log_err("Failed to open UDP socket: %s\n", strerror(errno)); + return -1; + } + + /* pass pktinfo struct on received packets */ +#if defined(IPV6_RECVPKTINFO) + opt_pktinfo = IPV6_RECVPKTINFO; +#elif defined(IPV6_PKTINFO) + opt_pktinfo = IPV6_PKTINFO; +#endif + if (setsockopt(sock, IPPROTO_IPV6, opt_pktinfo, &YES, sizeof(YES)) < 0) { + log_err("Failed to set IPv4 packet info socket option: %s\n", strerror(errno)); + goto err; + } + + /* bind the socket */ + memset(&sa, 0, sizeof(sa)); + sa.sin6_family = AF_INET6; + sa.sin6_port = htons(port); + + if (bind(sock, (struct sockaddr *)&sa, sizeof(sa)) < 0) { + log_err("Failed to bind() socket: %s\n", strerror(errno)); goto err; } @@ -111,3 +139,49 @@ err: close(sock); return -1; } + +int socket_mcast_group_ipv4(int sock, unsigned int ifindex, bool join) +{ + struct ip_mreqn mreq; + char ifname[IF_NAMESIZE]; + + /* silently ignore, we might not be listening on an IPv4 socket */ + if (sock < 0) + return -1; + + memset(&mreq, 0, sizeof(mreq)); + mreq.imr_ifindex = ifindex; + mreq.imr_address.s_addr = INADDR_ANY; + inet_pton(AF_INET, LLMNR_IPV4_MCAST_ADDR, &mreq.imr_multiaddr); + + if (setsockopt(sock, IPPROTO_IP, join ? IP_ADD_MEMBERSHIP : IP_DROP_MEMBERSHIP, + &mreq, sizeof(mreq)) < 0) { + log_err("Failed to join multicast group on interface %s: %s\n", + if_indextoname(ifindex, ifname), strerror(errno)); + return -1; + } + + return 0; +} + +int socket_mcast_group_ipv6(int sock, unsigned int ifindex, bool join) +{ + struct ipv6_mreq mreq; + char ifname[IF_NAMESIZE]; + + /* silently ignore, we might not be listening on an IPv6 socket */ + if (sock < 0) + return -1; + + memset(&mreq, 0, sizeof(mreq)); + inet_pton(AF_INET6, LLMNR_IPV6_MCAST_ADDR, &mreq.ipv6mr_multiaddr); + + if (setsockopt(sock, IPPROTO_IP, join ? IP_ADD_MEMBERSHIP : IP_DROP_MEMBERSHIP, + &mreq, sizeof(mreq)) < 0) { + log_err("Failed to join multicast group on interface %s: %s\n", + if_indextoname(ifindex, ifname), strerror(errno)); + return -1; + } + + return 0; +} @@ -19,9 +19,14 @@ #ifndef SOCKET_H #define SOCKET_H +#include <stdbool.h> #include <stdint.h> -int socket_open_v4(uint16_t port); +int socket_open_ipv4(uint16_t port); +int socket_open_ipv6(uint16_t port); int socket_open_rtnl(void); +int socket_mcast_group_ipv4(int sock, unsigned int ifindex, bool join); +int socket_mcast_group_ipv6(int sock, unsigned int ifindex, bool join); + #endif /* SOCKET_H */ |