[Linuxptp-users] PTP4L daemon seems to have a problem with to a link local address for IPv6

[Mario M. <mar...@we...>]

Hallo Richard,
I have make a observation that the PTP4L daemon seems to have a problem with to a link local address for IPv6 .
For IPV6 tests I have changed PTP_PRIMARY_MCAST_IP6ADDR  to a link local address.
(#define PTP_PRIMARY_MCAST_IP6ADDR "FF02:0:0:0:0:0:0:181")
After this change I have saw that the communication  and explicit the udp6_send didn't work.

I have review the the code of  udp6_send and I have saw that the sin6_sopce_id of struct sockaddr_in6 addr is not correct initialize.

I have corrected this and the communication problem disappears.

--- a/udp6.c
+++ b/udp6.c
@@ -135,6 +135,8 @@ enum { MC_PRIMARY, MC_PDELAY };
 
 static struct in6_addr mc6_addr[2];
 
+static unsigned ip6_scope_id;
+
 static int udp6_open(struct transport *t, char *name, struct fdarray *fda,
 		    enum timestamp_type ts_type)
 {
@@ -156,7 +158,8 @@ static int udp6_open(struct transport *t, char *name, struct fdarray *fda,
 
 	if (sk_timestamping_init(efd, name, ts_type, TRANS_UDP_IPV6))
 		goto no_timestamping;
-
+	
+	ip6_scope_id = if_nametoindex(name);
 	fda->fd[FD_EVENT] = efd;
 	fda->fd[FD_GENERAL] = gfd;
 	return 0;
@@ -181,11 +184,14 @@ static int udp6_send(struct transport *t, struct fdarray *fda, int event, int pe
 	ssize_t cnt;
 	int fd = event ? fda->fd[FD_EVENT] : fda->fd[FD_GENERAL];
 	struct sockaddr_in6 addr;
+	memset(&addr, 0, sizeof(struct sockaddr_in6)); /* Init */
+	
 	unsigned char junk[1600];
 
 	addr.sin6_family = AF_INET6;
 	addr.sin6_addr = peer ? mc6_addr[MC_PDELAY] : mc6_addr[MC_PRIMARY];
 	addr.sin6_port = htons(event ? EVENT_PORT : GENERAL_PORT);
+	addr.sin6_scope_id = ip6_scope_id;
 
 	len += 2; /* Extend the payload by two, for UDP checksum corrections. */
 -- 

Could you please check and review my changes?
I appreciate your opinion and ideas.
You can find the changes as patch file attached to this email.

Best Regards and thanks,
Mario