diff options
| author |   Matthew Smith <mgsmith@netgate.com> | 2022-11-05 18:33:08 +0000 |
|---|---|---|
| committer |   Dave Barach <openvpp@barachs.net> | 2022-11-06 12:48:15 +0000 |
| commit | ce1ff6a9b1ab2c4ab74165b26c92c2d551f53cf8 (patch) | |
| tree | d8eaeb827bee743bc71e3a6f82c6f2ab70c2cad6 /src/vnet/ip6-nd/ip6_nd_inline.h | |
| parent | f094ce7653917b8c331a79c088ef63ea2679c40d (diff) | |
ip6-nd: set router flag on NA if appropriate
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
Diffstat (limited to 'src/vnet/ip6-nd/ip6_nd_inline.h')
| -rw-r--r-- | src/vnet/ip6-nd/ip6_nd_inline.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/vnet/ip6-nd/ip6_nd_inline.h b/src/vnet/ip6-nd/ip6_nd_inline.h index 5e8b9d6e4c0..c959c94ed1d 100644 --- a/src/vnet/ip6-nd/ip6_nd_inline.h +++ b/src/vnet/ip6-nd/ip6_nd_inline.h @@ -23,6 +23,7 @@ #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> typedef enum { @@ -71,6 +72,13 @@ icmp6_send_neighbor_advertisement ( 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); |