Better handle IPv6 routes advertisement (non-)support.

Don't try to enable multiprotocol BGP when the peer says it can't.

Signed-off-by: Benjamin Cama <benoar@dolka.fr>
This commit is contained in:
Benjamin Cama 2011-07-20 17:46:21 +02:00
parent 7407c1a1c4
commit e86393ea90
2 changed files with 39 additions and 18 deletions

49
bgp.c
View file

@ -295,6 +295,8 @@ int bgp_start(struct bgp_peer *peer, char *name, int as, int keepalive,
BGP_PATH_ATTR_MP_UNREACH_NLRI_PARTIAL_SIZE); BGP_PATH_ATTR_MP_UNREACH_NLRI_PARTIAL_SIZE);
} }
peer->mp_handling = HandlingUnknown;
LOG(4, 0, 0, "Initiating BGP connection to %s (routing %s)\n", LOG(4, 0, 0, "Initiating BGP connection to %s (routing %s)\n",
name, enable ? "enabled" : "suspended"); name, enable ? "enabled" : "suspended");
@ -967,8 +969,6 @@ static int bgp_connect(struct bgp_peer *peer)
LOG(4, 0, 0, "BGP peer %s: state Active\n", inet_ntoa(addr.sin_addr)); LOG(4, 0, 0, "BGP peer %s: state Active\n", inet_ntoa(addr.sin_addr));
peer->handle_ipv6_routes = 0;
return bgp_send_open(peer); return bgp_send_open(peer);
} }
@ -992,8 +992,6 @@ static int bgp_handle_connect(struct bgp_peer *peer)
LOG(4, 0, 0, "BGP peer %s: state Active\n", peer->name); LOG(4, 0, 0, "BGP peer %s: state Active\n", peer->name);
peer->handle_ipv6_routes = 0;
return bgp_send_open(peer); return bgp_send_open(peer);
} }
@ -1260,7 +1258,7 @@ static int bgp_handle_input(struct bgp_peer *peer)
continue; continue;
} }
peer->handle_ipv6_routes = 1; peer->mp_handling = HandleIPv6Routes;
} }
} }
@ -1298,6 +1296,15 @@ static int bgp_handle_input(struct bgp_peer *peer)
return 0; return 0;
} }
if (notification->error_code == BGP_ERR_OPEN
&& notification->error_subcode == BGP_ERR_OPN_UNSUP_PARAM)
{
LOG(4, 0, 0, "BGP peer %s doesn't support BGP Capabilities\n", peer->name);
peer->mp_handling = DoesntHandleIPv6Routes;
bgp_restart(peer);
return 0;
}
if (notification->error_code == BGP_ERR_OPEN if (notification->error_code == BGP_ERR_OPEN
&& notification->error_subcode == BGP_ERR_OPN_UNSUP_CAP) && notification->error_subcode == BGP_ERR_OPN_UNSUP_CAP)
{ {
@ -1305,7 +1312,7 @@ static int bgp_handle_input(struct bgp_peer *peer)
an "unsupported capability" message, we disable IPv6 routes for an "unsupported capability" message, we disable IPv6 routes for
this peer */ this peer */
LOG(4, 0, 0, "BGP peer %s doesn't support IPv6 routes advertisement\n", peer->name); LOG(4, 0, 0, "BGP peer %s doesn't support IPv6 routes advertisement\n", peer->name);
peer->handle_ipv6_routes = 0; peer->mp_handling = DoesntHandleIPv6Routes;
break; break;
} }
@ -1354,20 +1361,28 @@ static int bgp_send_open(struct bgp_peer *peer)
data.hold_time = htons(peer->hold); data.hold_time = htons(peer->hold);
data.identifier = my_address; data.identifier = my_address;
/* construct the param and capability */ /* if we know peer doesn't support MP (mp_handling == DoesntHandleIPv6Routes)
cap_mp_ipv6.code = BGP_CAP_CODE_MP; then don't add this parameter */
cap_mp_ipv6.len = sizeof(mp_ipv6); if (peer->mp_handling == HandlingUnknown
memcpy(&cap_mp_ipv6.value, &mp_ipv6, cap_mp_ipv6.len); || peer->mp_handling == HandleIPv6Routes)
{
/* construct the param and capability */
cap_mp_ipv6.code = BGP_CAP_CODE_MP;
cap_mp_ipv6.len = sizeof(mp_ipv6);
memcpy(&cap_mp_ipv6.value, &mp_ipv6, cap_mp_ipv6.len);
param_cap_mp_ipv6.type = BGP_PARAM_TYPE_CAPABILITY; param_cap_mp_ipv6.type = BGP_PARAM_TYPE_CAPABILITY;
param_cap_mp_ipv6.len = 2 + sizeof(mp_ipv6); param_cap_mp_ipv6.len = 2 + sizeof(mp_ipv6);
memcpy(&param_cap_mp_ipv6.value, &cap_mp_ipv6, param_cap_mp_ipv6.len); memcpy(&param_cap_mp_ipv6.value, &cap_mp_ipv6, param_cap_mp_ipv6.len);
data.opt_len = 2 + param_cap_mp_ipv6.len; data.opt_len = 2 + param_cap_mp_ipv6.len;
memcpy(&data.opt_params, &param_cap_mp_ipv6, data.opt_len); memcpy(&data.opt_params, &param_cap_mp_ipv6, data.opt_len);
}
else
data.opt_len = 0;
memcpy(peer->outbuf->packet.data, &data, BGP_DATA_OPEN_SIZE); memcpy(peer->outbuf->packet.data, &data, BGP_DATA_OPEN_SIZE + data.opt_len);
len += BGP_DATA_OPEN_SIZE; len += BGP_DATA_OPEN_SIZE + data.opt_len;
peer->outbuf->packet.header.len = htons(len); peer->outbuf->packet.header.len = htons(len);
peer->outbuf->done = 0; peer->outbuf->done = 0;

8
bgp.h
View file

@ -209,6 +209,12 @@ struct bgp_buf {
size_t done; /* bytes sent/recvd */ size_t done; /* bytes sent/recvd */
}; };
enum bgp_mp_handling {
HandleIPv6Routes,
DoesntHandleIPv6Routes,
HandlingUnknown,
};
/* state */ /* state */
struct bgp_peer { struct bgp_peer {
char name[32]; /* peer name */ char name[32]; /* peer name */
@ -237,7 +243,7 @@ struct bgp_peer {
int path_attr_len_without_nexthop; /* length of path attrs without NEXT_HOP */ int path_attr_len_without_nexthop; /* length of path attrs without NEXT_HOP */
uint32_t events; /* events to poll */ uint32_t events; /* events to poll */
struct event_data edata; /* poll data */ struct event_data edata; /* poll data */
int handle_ipv6_routes; /* can handle IPv6 routes advertisements */ enum bgp_mp_handling mp_handling; /* how it handles IPv6 routes advertisements */
int update_routes6; /* UPDATE required for IPv6 routes */ int update_routes6; /* UPDATE required for IPv6 routes */
struct bgp_route6_list *routes6; /* IPv6 routes known by this peer */ struct bgp_route6_list *routes6; /* IPv6 routes known by this peer */
char mp_reach_nlri_partial[BGP_PATH_ATTR_MP_REACH_NLRI_PARTIAL_SIZE]; char mp_reach_nlri_partial[BGP_PATH_ATTR_MP_REACH_NLRI_PARTIAL_SIZE];