Add MTU to IPv6 routes on Linux.

diff --git a/if-linux.c b/if-linux.c
index 46b726cfe6c67828fda586ca1e480a0fa52ef2ac..eaf60c65f1a2b93ae94d7fc67fe48e28f1214375 100644 (file)
--- a/if-linux.c
+++ b/if-linux.c
@@ -614,10 +614,32 @@ if_address6(const struct interface *ifp, const struct ipv6_addr *ap, int action)
        return retval;
 }
 
+static int
+rta_add_attr_32(struct rtattr *rta, unsigned int maxlen,
+    int type, uint32_t data)
+{
+       unsigned int len = RTA_LENGTH(sizeof(data));
+       struct rtattr *subrta;
+
+       if (RTA_ALIGN(rta->rta_len) + len > maxlen) {
+               errno = ENOBUFS;
+               return -1;
+       }
+
+       subrta = (struct rtattr*)(((char*)rta) + RTA_ALIGN(rta->rta_len));
+       subrta->rta_type = type;
+       subrta->rta_len = len;
+       memcpy(RTA_DATA(subrta), &data, sizeof(data));
+       rta->rta_len = NLMSG_ALIGN(rta->rta_len) + len;
+       return 0;
+}
+
 int
 if_route6(const struct rt6 *rt, int action)
 {
        struct nlmr *nlm;
+       char metricsbuf[32];
+       struct rtattr *metrics = (void *)metricsbuf;
        int retval = 0;
 
        nlm = xzalloc(sizeof(*nlm));
@@ -659,6 +681,14 @@ if_route6(const struct rt6 *rt, int action)
        add_attr_32(&nlm->hdr, sizeof(*nlm), RTA_OIF, rt->iface->index);
        add_attr_32(&nlm->hdr, sizeof(*nlm), RTA_PRIORITY, rt->metric);
 
+       if (rt->mtu) {
+               metrics->rta_type = RTA_METRICS;
+               metrics->rta_len = RTA_LENGTH(0);
+               rta_add_attr_32(metrics, sizeof(metricsbuf), RTAX_MTU, rt->mtu);
+               add_attr_l(&nlm->hdr, sizeof(*nlm), RTA_METRICS,
+                   RTA_DATA(metrics), RTA_PAYLOAD(metrics));
+       }
+
        if (send_netlink(&nlm->hdr) == -1)
                retval = -1;
        free(nlm);