bgpd: bgpd-set-v4-nexthop-for-v6-peering.patch

BGP: While advertising v4 prefixes over a v6 session, set the correct v4 nexthop.

ISSUE:

For an IPv6 peer, BGPd sets the local router-id as the next-hop's v4 address.
This is incorrect as the router-id may not be a valid next-hop to be included
in UPDATEs that contain v4 prefixes.

PATCH:

Set the v4 address in the next-hop field based on the interface that the
peering is on (directly connected interface or loopback).

Signed-off-by: Pradosh Mohapatra <pmohapat at cumulusnetworks.com>
Reviewed-by: Scott Feldman <sfeldma at cumulusnetworks.com>
Acked-by: Feng Lu <lu.feng@6wind.com>
This commit is contained in:
Pradosh Mohapatra 2014-01-12 18:30:13 +00:00 committed by Vincent JARDIN
parent a83a1e9c2f
commit 6ee06fa9ed
2 changed files with 32 additions and 2 deletions

View File

@ -534,6 +534,25 @@ if_get_ipv6_local (struct interface *ifp, struct in6_addr *addr)
}
#endif /* HAVE_IPV6 */
static int
if_get_ipv4_address (struct interface *ifp, struct in_addr *addr)
{
struct listnode *cnode;
struct connected *connected;
struct prefix *cp;
for (ALL_LIST_ELEMENTS_RO (ifp->connected, cnode, connected))
{
cp = connected->address;
if ((cp->family == AF_INET) && !ipv4_martian(&(cp->u.prefix4)))
{
*addr = cp->u.prefix4;
return 1;
}
}
return 0;
}
int
bgp_nexthop_set (union sockunion *local, union sockunion *remote,
struct bgp_nexthop *nexthop, struct peer *peer)
@ -592,8 +611,9 @@ bgp_nexthop_set (union sockunion *local, union sockunion *remote,
{
struct interface *direct = NULL;
/* IPv4 nexthop. I don't care about it. */
if (peer->local_id.s_addr)
/* IPv4 nexthop. */
ret = if_get_ipv4_address(ifp, &nexthop->v4);
if (!ret && peer->local_id.s_addr)
nexthop->v4 = peer->local_id;
/* Global address*/

View File

@ -196,4 +196,14 @@ extern const char *inet6_ntoa (struct in6_addr);
extern int all_digit (const char *);
static inline int ipv4_martian (struct in_addr *addr)
{
in_addr_t ip = addr->s_addr;
if (IPV4_NET0(ip) || IPV4_NET127(ip) || IPV4_CLASS_DE(ip)) {
return 1;
}
return 0;
}
#endif /* _ZEBRA_PREFIX_H */