NetBSD: Gear up for kernel RA removal.

linkmtu will vanish from nd_ifinfo along with other things.
Also, there is not need to pre-fetch ifinfo because flags are no
longer updated when setting ifinfo back again.

diff --git a/src/if-bsd.c b/src/if-bsd.c
index 3c8950ca8f4c1709260b9b1bbf3c124a6e693110..3f3f60705324697a143451b254ccbc7d0e1d98e1 100644 (file)
--- a/src/if-bsd.c
+++ b/src/if-bsd.c
@@ -1476,19 +1476,31 @@ int
 if_applyra(const struct ra *rap)
 {
 #ifdef SIOCSIFINFO_IN6
-       struct in6_ndireq ndi = { .ndi.chlim = 0 };
-       struct priv *priv = rap->iface->ctx->priv;
+       struct in6_ndireq nd = { .ndi.chlim = 0 };
+       struct dhcpcd_ctx *ctx = rap->iface->ctx;
+       struct priv *priv = ctx->priv;
        int error;
 
-       strlcpy(ndi.ifname, rap->iface->name, sizeof(ndi.ifname));
-       if (ioctl(priv->pf_inet6_fd, SIOCGIFINFO_IN6, &ndi) == -1)
+       strlcpy(nd.ifname, rap->iface->name, sizeof(nd.ifname));
+
+#ifdef IPV6CTL_ACCEPT_RTADV
+       /*
+        * NetBSD changed SIOCSIFINFO_IN6 to NOT set flags when kernel
+        * RA was removed, however both FreeBSD and DragonFlyBSD still do.
+        * linkmtu was also removed.
+        * Hopefully this guard will still work if either remove kernel RA.
+        */
+       if (ioctl(priv->pf_inet6_fd, SIOCGIFINFO_IN6, &nd, sizeof(nd)) == -1)
                return -1;
 
-       ndi.ndi.linkmtu = rap->mtu;
-       ndi.ndi.chlim = rap->hoplimit;
-       ndi.ndi.retrans = rap->retrans;
-       ndi.ndi.basereachable = rap->reachable;
-       error = ioctl(priv->pf_inet6_fd, SIOCSIFINFO_IN6, &ndi);
+       nd.ndi.linkmtu = rap->mtu;
+#endif
+
+       nd.ndi.chlim = rap->hoplimit;
+       nd.ndi.retrans = rap->retrans;
+       nd.ndi.basereachable = rap->reachable;
+       error = ioctl(priv->pf_inet6_fd, SIOCSIFINFO_IN6, &nd, sizeof(nd));
+#ifdef IPV6CTL_ACCEPT_RTADV
        if (error == -1 && errno == EINVAL) {
                /*
                 * Very likely that this is caused by a dodgy MTU
@@ -1500,6 +1512,7 @@ if_applyra(const struct ra *rap)
                ndi.ndi.linkmtu = 0;
                error = ioctl(priv->pf_inet6_fd, SIOCSIFINFO_IN6, &ndi);
        }
+#endif
        return error;
 #else
 #warning OS does not allow setting of RA bits hoplimit, retrans or reachable