vrrpd: fix ownership discovery and mcast OIF

* Look for virtual IP ownership on the parent of the macvlan, not the
  macvlan itself
* IPv4: bind socket to real IP of the macvlan parent, but transmit on
  the macvlan interface
* IPv6: bind socket to IPv6 link local of the macvlan interface

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

diff --git a/vrrpd/vrrp.c b/vrrpd/vrrp.c
index 1f89ef7b96dc344fd925d0186b1846feadee8603..3677e9c76dd2095b5853699b7a6787627bda596a 100644 (file)
--- a/vrrpd/vrrp.c
+++ b/vrrpd/vrrp.c
@@ -107,35 +107,15 @@ static void vrrp_recalculate_timers(struct vrrp_router *r)
  * Returns:
  *    whether or not vr owns the specified address
  */
-static bool vrrp_is_owner(struct vrrp_vrouter *vr, struct ipaddr *addr)
+static bool vrrp_is_owner(struct interface *ifp, struct ipaddr *addr)
 {
-       struct prefix *p;
-       struct prefix_ipv4 p4;
-       struct prefix_ipv6 p6;
-       struct vrrp_router *r;
-
-       if (IS_IPADDR_V4(addr)) {
-               p4.family = AF_INET;
-               p4.prefixlen = IPV4_MAX_BITLEN;
-               p4.prefix = addr->ipaddr_v4;
-               p = (struct prefix *)&p4;
-               r = vr->v4;
-       } else {
-               p6.family = AF_INET6;
-               p6.prefixlen = IPV6_MAX_BITLEN;
-               memcpy(&p6.prefix, &addr->ipaddr_v6, sizeof(struct in6_addr));
-               p = (struct prefix *)&p6;
-               r = vr->v6;
-       }
+       struct prefix p;
 
-       bool have_addr = !!connected_lookup_prefix_exact(r->mvl_ifp, p);
+       p.family = IS_IPADDR_V4(addr) ? AF_INET : AF_INET6;
+       p.prefixlen = IS_IPADDR_V4(addr) ? IPV4_MAX_BITLEN : IPV6_MAX_BITLEN;
+       memcpy(&p.u, &addr->ip, sizeof(addr->ip));
 
-       /* did we assign it? */
-       /* FIXME: this check is wrong, we need a flag to set when we install
-        * addresses on an interface when assuming master status; then
-        * ownership status is determined by (have_addr && !flag) in master
-        * state */
-       return have_addr;
+       return !!connected_lookup_prefix_exact(ifp, &p);
 }
 
 /* Configuration controllers ----------------------------------------------- */
@@ -166,7 +146,7 @@ void vrrp_add_ipv4(struct vrrp_vrouter *vr, struct in_addr v4)
        v4_ins->ipa_type = IPADDR_V4;
        v4_ins->ipaddr_v4 = v4;
 
-       if (!vrrp_is_owner(vr, v4_ins) && vr->v4->is_owner) {
+       if (!vrrp_is_owner(vr->ifp, v4_ins) && vr->v4->is_owner) {
                char ipbuf[INET6_ADDRSTRLEN];
                ipaddr2str(v4_ins, ipbuf, sizeof(ipbuf));
                zlog_err(
@@ -187,7 +167,7 @@ void vrrp_add_ipv6(struct vrrp_vrouter *vr, struct in6_addr v6)
        v6_ins->ipa_type = IPADDR_V6;
        memcpy(&v6_ins->ipaddr_v6, &v6, sizeof(struct in6_addr));
 
-       if (!vrrp_is_owner(vr, v6_ins) && vr->v6->is_owner) {
+       if (!vrrp_is_owner(vr->ifp, v6_ins) && vr->v6->is_owner) {
                char ipbuf[INET6_ADDRSTRLEN];
                ipaddr2str(v6_ins, ipbuf, sizeof(ipbuf));
                zlog_err(
@@ -271,7 +251,7 @@ static struct vrrp_router *vrrp_router_create(struct vrrp_vrouter *vr,
                zlog_info(VRRP_LOGPFX VRRP_LOGPFX_VRID "Selected %s",
                          r->vr->vrid, selection->name);
 
-       r->mvl_ifp = selection ? selection : r->vr->ifp;
+       r->mvl_ifp = selection;
 
        return r;
 }
@@ -553,34 +533,44 @@ done:
 static int vrrp_bind_to_primary_connected(struct vrrp_router *r)
 {
        char ipstr[INET6_ADDRSTRLEN];
+       struct interface *ifp;
+
+       /*
+        * A slight quirk: the RFC specifies that advertisements under IPv6 must
+        * be transmitted using the link local address of the source interface
+        */
+       ifp = r->family == AF_INET ? r->vr->ifp : r->mvl_ifp;
 
        struct listnode *ln;
        struct connected *c = NULL;
-       for (ALL_LIST_ELEMENTS_RO(r->mvl_ifp->connected, ln, c))
+       for (ALL_LIST_ELEMENTS_RO(ifp->connected, ln, c))
                if (c->address->family == r->family)
                        break;
 
        if (c == NULL) {
                zlog_err(VRRP_LOGPFX VRRP_LOGPFX_VRID
                         "Failed to find %s address to bind on %s",
-                        r->vr->vrid, family2str(r->family), r->mvl_ifp->name);
+                        r->vr->vrid, family2str(r->family), ifp->name);
                return -1;
        }
 
-       struct sockaddr_in sa4 = {
-               .sin_family = AF_INET,
-               .sin_addr = c->address->u.prefix4,
-       };
-       struct sockaddr_in6 sa6 = {
-               .sin6_family = AF_INET6,
-               .sin6_addr = c->address->u.prefix6,
-       };
+       union sockunion su;
+       memset(&su, 0x00, sizeof(su));
 
-       struct sockaddr *sa = r->family == AF_INET ? (struct sockaddr *)&sa4
-                                                  : (struct sockaddr *)&sa6;
+       switch (r->family) {
+       case AF_INET:
+               su.sin.sin_family = AF_INET;
+               su.sin.sin_addr = c->address->u.prefix4;
+               break;
+       case AF_INET6:
+               su.sin6.sin6_family = AF_INET6;
+               su.sin6.sin6_scope_id = ifp->ifindex;
+               su.sin6.sin6_addr = c->address->u.prefix6;
+               break;
+       }
 
        sockopt_reuseaddr(r->sock_tx);
-       if (bind(r->sock_tx, sa, sizeof(struct sockaddr)) < 0) {
+       if (bind(r->sock_tx, (const struct sockaddr *)&su, sizeof(su)) < 0) {
                zlog_err(
                        VRRP_LOGPFX VRRP_LOGPFX_VRID
                        "Failed to bind Tx socket to primary IP address %s: %s",
@@ -677,6 +667,23 @@ static int vrrp_socket(struct vrrp_router *r)
                ret = setsockopt_ipv4_multicast(r->sock_rx, IP_ADD_MEMBERSHIP,
                                                v4, htonl(VRRP_MCASTV4_GROUP),
                                                r->vr->ifp->ifindex);
+
+               /* Set outgoing interface for advertisements */
+               struct ip_mreqn mreqn = {};
+               mreqn.imr_ifindex = r->mvl_ifp->ifindex;
+               ret = setsockopt(r->sock_tx, IPPROTO_IP, IP_MULTICAST_IF,
+                                (void *)&mreqn, sizeof(mreqn));
+               if (ret < 0) {
+                       zlog_warn(
+                               VRRP_LOGPFX VRRP_LOGPFX_VRID
+                               "Could not set %s as outgoing multicast interface",
+                               r->vr->vrid, r->mvl_ifp->name);
+                       failed = true;
+                       goto done;
+               }
+               zlog_info(VRRP_LOGPFX VRRP_LOGPFX_VRID
+                         "Set %s as outgoing multicast interface",
+                         r->vr->vrid, r->mvl_ifp->name);
        } else if (r->family == AF_INET6) {
                /* Always transmit IPv6 packets with hop limit set to 255 */
                ret = setsockopt_ipv6_multicast_hops(r->sock_tx, 255);
@@ -702,6 +709,21 @@ static int vrrp_socket(struct vrrp_router *r)
                mreq.ipv6mr_interface = r->vr->ifp->ifindex;
                ret = setsockopt(r->sock_rx, IPPROTO_IPV6, IPV6_JOIN_GROUP,
                                 &mreq, sizeof(mreq));
+
+               /* Set outgoing interface for advertisements */
+               ret = setsockopt(r->sock_tx, IPPROTO_IPV6, IPV6_MULTICAST_IF,
+                                &r->mvl_ifp->ifindex, sizeof(ifindex_t));
+               if (ret < 0) {
+                       zlog_warn(
+                               VRRP_LOGPFX VRRP_LOGPFX_VRID
+                               "Could not set %s as outgoing multicast interface",
+                               r->vr->vrid, r->mvl_ifp->name);
+                       failed = true;
+                       goto done;
+               }
+               zlog_info(VRRP_LOGPFX VRRP_LOGPFX_VRID
+                         "Set %s as outgoing multicast interface",
+                         r->vr->vrid, r->mvl_ifp->name);
        }
 
        if (ret < 0) {
@@ -879,6 +901,14 @@ static int vrrp_startup(struct vrrp_router *r)
        if (r->fsm.state != VRRP_STATE_INITIALIZE)
                return -1;
 
+       /* Must have a valid macvlan interface available */
+       if (r->mvl_ifp == NULL) {
+               zlog_warn(VRRP_LOGPFX VRRP_LOGPFX_VRID
+                         "No appropriate interface for %s VRRP found",
+                         r->vr->vrid, family2str(r->family));
+               return -1;
+       }
+
        /* Initialize global gratuitous ARP socket if necessary */
        if (r->family == AF_INET && !vrrp_garp_is_init())
                vrrp_garp_init();
@@ -899,7 +929,7 @@ static int vrrp_startup(struct vrrp_router *r)
        char ipbuf[INET6_ADDRSTRLEN];
        inet_ntop(r->family, &primary->ip.addr, ipbuf, sizeof(ipbuf));
 
-       if (vrrp_is_owner(r->vr, primary)) {
+       if (vrrp_is_owner(r->vr->ifp, primary)) {
                r->priority = VRRP_PRIO_MASTER;
                vrrp_recalculate_timers(r);