diff options
| -rw-r--r-- | bgpd/bgp_attr.c | 45 | ||||
| -rw-r--r-- | lib/prefix.h | 1 |
2 files changed, 40 insertions, 6 deletions
diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c index d1ba0dac..6905ab52 100644 --- a/bgpd/bgp_attr.c +++ b/bgpd/bgp_attr.c @@ -964,15 +964,31 @@ bgp_attr_nexthop (struct peer *peer, bgp_size_t length, struct attr *attr, u_char flag, u_char *startp) { bgp_size_t total; + in_addr_t nexthop_h, nexthop_n; total = length + (CHECK_FLAG (flag, BGP_ATTR_FLAG_EXTLEN) ? 4 : 3); - /* Flag check. */ - if (CHECK_FLAG (flag, BGP_ATTR_FLAG_OPTIONAL) - || ! CHECK_FLAG (flag, BGP_ATTR_FLAG_TRANS)) + /* Flags check. */ + if (CHECK_FLAG (flag, BGP_ATTR_FLAG_OPTIONAL)) { - zlog (peer->log, LOG_ERR, - "Origin attribute flag isn't transitive %d", flag); + zlog (peer->log, LOG_ERR, + "NEXT_HOP attribute must not be flagged as \"optional\" (%u)", flag); + return bgp_attr_malformed (peer, BGP_ATTR_NEXT_HOP, flag, + BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR, + startp, total); + } + if (! CHECK_FLAG (flag, BGP_ATTR_FLAG_TRANS)) + { + zlog (peer->log, LOG_ERR, + "NEXT_HOP attribute must be flagged as \"transitive\" (%u)", flag); + return bgp_attr_malformed (peer, BGP_ATTR_NEXT_HOP, flag, + BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR, + startp, total); + } + if (CHECK_FLAG (flag, BGP_ATTR_FLAG_PARTIAL)) + { + zlog (peer->log, LOG_ERR, + "NEXT_HOP attribute must not be flagged as \"partial\" (%u)", flag); return bgp_attr_malformed (peer, BGP_ATTR_NEXT_HOP, flag, BGP_NOTIFY_UPDATE_ATTR_FLAG_ERR, startp, total); @@ -989,7 +1005,24 @@ bgp_attr_nexthop (struct peer *peer, bgp_size_t length, startp, total); } - attr->nexthop.s_addr = stream_get_ipv4 (peer->ibuf); + /* According to section 6.3 of RFC4271, syntactically incorrect NEXT_HOP + attribute must result in a NOTIFICATION message (this is implemented below). + At the same time, semantically incorrect NEXT_HOP is more likely to be just + logged locally (this is implemented somewhere else). The UPDATE message + gets ignored in any of these cases. */ + nexthop_n = stream_get_ipv4 (peer->ibuf); + nexthop_h = ntohl (nexthop_n); + if (IPV4_NET0 (nexthop_h) || IPV4_NET127 (nexthop_h) || IPV4_CLASS_DE (nexthop_h)) + { + char buf[INET_ADDRSTRLEN]; + inet_ntop (AF_INET, &nexthop_h, buf, INET_ADDRSTRLEN); + zlog (peer->log, LOG_ERR, "Martian nexthop %s", buf); + return bgp_attr_malformed (peer, BGP_ATTR_NEXT_HOP, flag, + BGP_NOTIFY_UPDATE_INVAL_NEXT_HOP, + startp, total); + } + + attr->nexthop.s_addr = nexthop_n; attr->flag |= ATTR_FLAG_BIT (BGP_ATTR_NEXT_HOP); return BGP_ATTR_PARSE_PROCEED; diff --git a/lib/prefix.h b/lib/prefix.h index 5f1ff05c..1cb91b2a 100644 --- a/lib/prefix.h +++ b/lib/prefix.h @@ -112,6 +112,7 @@ struct prefix_rd #define IPV4_NET0(a) ((((u_int32_t) (a)) & 0xff000000) == 0x00000000) #define IPV4_NET127(a) ((((u_int32_t) (a)) & 0xff000000) == 0x7f000000) #define IPV4_LINKLOCAL(a) ((((u_int32_t) (a)) & 0xffff0000) == 0xa9fe0000) +#define IPV4_CLASS_DE(a) ((u_int32_t) (a) >= 0xe0000000) /* Max bit/byte length of IPv6 address. */ #define IPV6_MAX_BYTELEN 16 |