vrrpd: allow searching for interfaces late

Break out code for assigning macvlan interface to a vrrp router into its
own function so it can be called multiple times. This allows bringing up
IPv4 and IPv6 at different times if all the interfaces are not created
yet.

Signed-off-by: Quentin Young <qlyoung@cumulusnetworks.com>

1 files changed, 34 insertions, 17 deletions

diff --git a/vrrpd/vrrp.c b/vrrpd/vrrp.c
index c6ca897f4..0cc9ed0e9 100644
--- a/vrrpd/vrrp.c
+++ b/vrrpd/vrrp.c
@@ -200,21 +200,18 @@ static void vrrp_router_addr_list_del_cb(void *val)
 	XFREE(MTYPE_TMP, ip);
 }
 
-static struct vrrp_router *vrrp_router_create(struct vrrp_vrouter *vr,
-					      int family)
+/*
+ * Search for a suitable macvlan subinterface we can attach to, and if found,
+ * attach to it.
+ *
+ * r
+ *    Router to attach to interface
+ *
+ * Returns:
+ *    Whether an interface was successfully attached
+ */
+static bool vrrp_attach_interface(struct vrrp_router *r)
 {
-	struct vrrp_router *r = XCALLOC(MTYPE_TMP, sizeof(struct vrrp_router));
-
-	r->family = family;
-	r->sock_rx = -1;
-	r->sock_tx = -1;
-	r->vr = vr;
-	r->addrs = list_new();
-	r->addrs->del = vrrp_router_addr_list_del_cb;
-	r->priority = vr->priority;
-	r->fsm.state = VRRP_STATE_INITIALIZE;
-	vrrp_mac_set(&r->vmac, family == AF_INET6, vr->vrid);
-
 	/* Search for existing interface with computed MAC address */
 	struct interface **ifps;
 	size_t ifps_cnt = if_lookup_by_hwaddr(
@@ -231,7 +228,6 @@ static struct vrrp_router *vrrp_router_create(struct vrrp_vrouter *vr,
 	unsigned int candidates = 0;
 	struct interface *selection = NULL;
 	for (unsigned int i = 0; i < ifps_cnt; i++) {
-		zlog_info("Found VRRP interface %s", ifps[i]->name);
 		if (strncmp(ifps[i]->name, r->vr->ifp->name,
 			    strlen(r->vr->ifp->name)))
 			ifps[i] = NULL;
@@ -251,7 +247,7 @@ static struct vrrp_router *vrrp_router_create(struct vrrp_vrouter *vr,
 
 	if (candidates == 0)
 		zlog_warn(VRRP_LOGPFX VRRP_LOGPFX_VRID
-			  "No interface found w/ MAC %s; using default",
+			  "No interface found w/ MAC %s",
 			  r->vr->vrid, ethstr);
 	else if (candidates > 1)
 		zlog_warn(VRRP_LOGPFX VRRP_LOGPFX_VRID
@@ -263,6 +259,27 @@ static struct vrrp_router *vrrp_router_create(struct vrrp_vrouter *vr,
 
 	r->mvl_ifp = selection;
 
+	return !!r->mvl_ifp;
+
+}
+
+static struct vrrp_router *vrrp_router_create(struct vrrp_vrouter *vr,
+					      int family)
+{
+	struct vrrp_router *r = XCALLOC(MTYPE_TMP, sizeof(struct vrrp_router));
+
+	r->family = family;
+	r->sock_rx = -1;
+	r->sock_tx = -1;
+	r->vr = vr;
+	r->addrs = list_new();
+	r->addrs->del = vrrp_router_addr_list_del_cb;
+	r->priority = vr->priority;
+	r->fsm.state = VRRP_STATE_INITIALIZE;
+	vrrp_mac_set(&r->vmac, family == AF_INET6, vr->vrid);
+
+	vrrp_attach_interface(r);
+
 	return r;
 }
 
@@ -1011,7 +1028,7 @@ static int vrrp_startup(struct vrrp_router *r)
 		return -1;
 
 	/* Must have a valid macvlan interface available */
-	if (r->mvl_ifp == NULL) {
+	if (r->mvl_ifp == NULL && !vrrp_attach_interface(r)) {
 		zlog_warn(VRRP_LOGPFX VRRP_LOGPFX_VRID
 			  "No appropriate interface for %s VRRP found",
 			  r->vr->vrid, family2str(r->family));