Type: fix
The router flag on a neighbor advertisement can be used by neighbors to
detect that a router has changed to a host (RFC 4861 section 4.4).
If a neighbor adds routes after receiving a router advertisement sent
by VPP and subsequently receives a neighbor advertisement sent by VPP,
it may remove any routes it added based on the RA if the NA does not
have the router flag set. It appears that this is how windows behaves.
When sending a neighbor advertisement, set the router flag if sending
RAs is enabled on the interface.
Signed-off-by: Matthew Smith <mgsmith@netgate.com>
Change-Id: I1f3e42bbd8ea1a4c116b1ce5a8273652d4cd763d
#include <vnet/ip/icmp46_packet.h>
#include <vnet/ip/ip6.h>
#include <vnet/ip-neighbor/ip_neighbor_types.h>
#include <vnet/ip/icmp46_packet.h>
#include <vnet/ip/ip6.h>
#include <vnet/ip-neighbor/ip_neighbor_types.h>
+#include <vnet/ip6-nd/ip6_ra.h>
clib_host_to_net_u32 (ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_SOLICITED |
ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE);
clib_host_to_net_u32 (ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_SOLICITED |
ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_OVERRIDE);
+ /* if sending RAs is enabled, the "router" flag should be set,
+ * otherwise, neighbors may believe we have changed from a router
+ * to a host - RFC 4861 section 4.4 */
+ if (ip6_ra_adv_enabled (sw_if_index0))
+ icmp6_nsa->advertisement_flags |=
+ clib_host_to_net_u32 (ICMP6_NEIGHBOR_ADVERTISEMENT_FLAG_ROUTER);
+
icmp6_nsa->icmp.checksum = 0;
icmp6_nsa->icmp.checksum =
ip6_tcp_udp_icmp_compute_checksum (vm, b, ip6_h, &bogus_length);
icmp6_nsa->icmp.checksum = 0;
icmp6_nsa->icmp.checksum =
ip6_tcp_udp_icmp_compute_checksum (vm, b, ip6_h, &bogus_length);
+u8
+ip6_ra_adv_enabled (u32 sw_if_index)
+{
+ ip6_ra_t *ra;
+
+ ra = ip6_ra_get_itf (sw_if_index);
+
+ return ((ra != NULL) && (ra->send_radv != 0));
+}
+
/* for "syslogging" - use elog for now */
#define foreach_log_level \
_ (DEBUG, "DEBUG") \
/* for "syslogging" - use elog for now */
#define foreach_log_level \
_ (DEBUG, "DEBUG") \
u32 primary_sw_if_index,
u32 valid_time,
u32 preferred_time);
u32 primary_sw_if_index,
u32 valid_time,
u32 preferred_time);
+extern u8 ip6_ra_adv_enabled (u32 sw_if_index);
#endif /* included_ip6_neighbor_h */
/*
#endif /* included_ip6_neighbor_h */
/*