From d4995c6d71ded118dc90834fd1f886b47ad75301 Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Wed, 12 Aug 2015 18:45:42 +0200 Subject: [PATCH] udp: configure the socket with the TTL option. Signed-off-by: Richard Cochran --- udp.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/udp.c b/udp.c index b100dbf..b8aa76a 100644 --- a/udp.c +++ b/udp.c @@ -30,6 +30,7 @@ #include #include "address.h" +#include "config.h" #include "contain.h" #include "print.h" #include "sk.h" @@ -92,7 +93,8 @@ static int udp_close(struct transport *t, struct fdarray *fda) return 0; } -static int open_socket(const char *name, struct in_addr mc_addr[2], short port) +static int open_socket(const char *name, struct in_addr mc_addr[2], short port, + int ttl) { struct sockaddr_in addr; int fd, index, on = 1; @@ -123,6 +125,10 @@ static int open_socket(const char *name, struct in_addr mc_addr[2], short port) pr_err("setsockopt SO_BINDTODEVICE failed: %m"); goto no_option; } + if (setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl))) { + pr_err("setsockopt IP_MULTICAST_TTL failed: %m"); + goto no_option; + } addr.sin_addr = mc_addr[0]; if (mcast_join(fd, index, (struct sockaddr *) &addr, sizeof(addr))) { pr_err("mcast_join failed"); @@ -151,8 +157,9 @@ static int udp_open(struct transport *t, const char *name, struct fdarray *fda, enum timestamp_type ts_type) { struct udp *udp = container_of(t, struct udp, t); - int efd, gfd; + int efd, gfd, ttl; + ttl = config_get_int(t->cfg, name, "udp_ttl"); udp->mac.len = 0; sk_interface_macaddr(name, &udp->mac); @@ -165,11 +172,11 @@ static int udp_open(struct transport *t, const char *name, struct fdarray *fda, if (!inet_aton(PTP_PDELAY_MCAST_IPADDR, &mcast_addr[MC_PDELAY])) return -1; - efd = open_socket(name, mcast_addr, EVENT_PORT); + efd = open_socket(name, mcast_addr, EVENT_PORT, ttl); if (efd < 0) goto no_event; - gfd = open_socket(name, mcast_addr, GENERAL_PORT); + gfd = open_socket(name, mcast_addr, GENERAL_PORT, ttl); if (gfd < 0) goto no_general;