diff options
| author | Ondrej Zajicek (work) <santiago@crfreenet.org> | 2017-02-23 16:32:07 +0100 |
|---|---|---|
| committer | Ondrej Zajicek (work) <santiago@crfreenet.org> | 2017-02-23 16:32:07 +0100 |
| commit | 1950a479c020d1972b6007d8ea0f66e3d4f8564a (patch) | |
| tree | 6f023363fb7536eb912e4b373039e8c283626a8b /proto | |
| parent | 4e379bde60172823452cf96e9c0b6b1737c490f0 (diff) | |
BGP: Allow exchanging LOCAL_PREF with eBGP peers
Adds option 'allow bgp_local_pref' to override the usual restriction of
LOCAL_PREF on eBGP sessions.
Thanks to Lennert Buytenhek for the patch.
Diffstat (limited to 'proto')
| -rw-r--r-- | proto/bgp/attrs.c | 20 | ||||
| -rw-r--r-- | proto/bgp/bgp.h | 1 | ||||
| -rw-r--r-- | proto/bgp/config.Y | 1 |
3 files changed, 17 insertions, 5 deletions
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c index 2b0a92dc..b9e2490d 100644 --- a/proto/bgp/attrs.c +++ b/proto/bgp/attrs.c @@ -306,7 +306,7 @@ static struct attr_desc bgp_attr_table[] = { bgp_check_next_hop, bgp_format_next_hop }, { "med", 4, BAF_OPTIONAL, EAF_TYPE_INT, 1, /* BA_MULTI_EXIT_DISC */ NULL, NULL }, - { "local_pref", 4, BAF_TRANSITIVE, EAF_TYPE_INT, 0, /* BA_LOCAL_PREF */ + { "local_pref", 4, BAF_TRANSITIVE, EAF_TYPE_INT, 1, /* BA_LOCAL_PREF */ NULL, NULL }, { "atomic_aggr", 0, BAF_TRANSITIVE, EAF_TYPE_OPAQUE, 1, /* BA_ATOMIC_AGGR */ NULL, NULL }, @@ -821,8 +821,13 @@ bgp_get_bucket(struct bgp_proto *p, net *n, ea_list *attrs, int originate) code = EA_ID(a->id); if (ATTR_KNOWN(code)) { - if (!bgp_attr_table[code].allow_in_ebgp && !p->is_internal) - continue; + if (!p->is_internal) + { + if (!bgp_attr_table[code].allow_in_ebgp) + continue; + if ((code == BA_LOCAL_PREF) && !p->cf->allow_local_pref) + continue; + } /* The flags might have been zero if the attr was added by filters */ a->flags = (a->flags & BAF_PARTIAL) | bgp_attr_table[code].expected_flags; if (code < 32) @@ -1776,8 +1781,13 @@ bgp_decode_attrs(struct bgp_conn *conn, byte *attr, uint len, struct linpool *po { errcode = 5; goto err; } if ((desc->expected_flags ^ flags) & (BAF_OPTIONAL | BAF_TRANSITIVE)) { errcode = 4; goto err; } - if (!desc->allow_in_ebgp && !bgp->is_internal) - continue; + if (!bgp->is_internal) + { + if (!desc->allow_in_ebgp) + continue; + if ((code == BA_LOCAL_PREF) && !bgp->cf->allow_local_pref) + continue; + } if (desc->validate) { errcode = desc->validate(bgp, z, l); diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h index bf933554..e47a0eb1 100644 --- a/proto/bgp/bgp.h +++ b/proto/bgp/bgp.h @@ -50,6 +50,7 @@ struct bgp_config { int secondary; /* Accept also non-best routes (i.e. RA_ACCEPTED) */ int add_path; /* Use ADD-PATH extension [RFC7911] */ int allow_local_as; /* Allow that number of local ASNs in incoming AS_PATHs */ + int allow_local_pref; /* Allow LOCAL_PREF in EBGP sessions */ int gr_mode; /* Graceful restart mode (BGP_GR_*) */ int setkey; /* Set MD5 password to system SA/SP database */ unsigned gr_time; /* Graceful restart timeout */ diff --git a/proto/bgp/config.Y b/proto/bgp/config.Y index 32ae88a3..55c602f1 100644 --- a/proto/bgp/config.Y +++ b/proto/bgp/config.Y @@ -126,6 +126,7 @@ bgp_proto: | bgp_proto ADD PATHS RX ';' { BGP_CFG->add_path = ADD_PATH_RX; } | bgp_proto ADD PATHS TX ';' { BGP_CFG->add_path = ADD_PATH_TX; } | bgp_proto ADD PATHS bool ';' { BGP_CFG->add_path = $4 ? ADD_PATH_FULL : 0; } + | bgp_proto ALLOW BGP_LOCAL_PREF bool ';' { BGP_CFG->allow_local_pref = $4; } | bgp_proto ALLOW LOCAL AS ';' { BGP_CFG->allow_local_as = -1; } | bgp_proto ALLOW LOCAL AS expr ';' { BGP_CFG->allow_local_as = $5; } | bgp_proto GRACEFUL RESTART bool ';' { BGP_CFG->gr_mode = $4; } |