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-rw-r--r--proto/bgp/attrs.c12
-rw-r--r--proto/bgp/bgp.c9
-rw-r--r--proto/bgp/bgp.h4
-rw-r--r--proto/bgp/packets.c180
4 files changed, 131 insertions, 74 deletions
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index dc267fdb..dcc4a273 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -285,15 +285,20 @@ bgp_encode_next_hop(struct bgp_write_state *s, eattr *a, byte *buf, uint size)
* store it and encode it later by AFI-specific hooks.
*/
- if ((s->channel->afi == BGP_AF_IPV4) && !s->channel->ext_next_hop)
+ if (!s->mp_reach)
{
- ASSERT(a->u.ptr->length == sizeof(ip_addr));
+ // ASSERT(a->u.ptr->length == sizeof(ip_addr));
+
+ /* FIXME: skip IPv6 next hops for IPv4 routes during MRT dump */
+ ip_addr *addr = (void *) a->u.ptr->data;
+ if ((a->u.ptr->length != sizeof(ip_addr)) || !ipa_is_ip4(*addr))
+ return 0;
if (size < (3+4))
return -1;
bgp_put_attr_hdr3(buf, BA_NEXT_HOP, a->flags, 4);
- put_ip4(buf+3, ipa_to_ip4( *(ip_addr *) a->u.ptr->data ));
+ put_ip4(buf+3, ipa_to_ip4(*addr));
return 3+4;
}
@@ -946,6 +951,7 @@ bgp_encode_attr(struct bgp_write_state *s, eattr *a, byte *buf, uint size)
*
* The bgp_encode_attrs() function takes a list of extended attributes
* and converts it to its BGP representation (a part of an Update message).
+ * BGP write state may be fake when called from MRT protocol.
*
* Result: Length of the attribute block generated or -1 if not enough space.
*/
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index e2a57137..7f2eb4d0 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -477,7 +477,7 @@ static inline void
bgp_conn_set_state(struct bgp_conn *conn, uint new_state)
{
if (conn->bgp->p.mrtdump & MD_STATES)
- mrt_dump_bgp_state_change(conn, conn->state, new_state);
+ bgp_dump_state_change(conn, conn->state, new_state);
conn->state = new_state;
}
@@ -528,6 +528,9 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
/* Number of active channels */
int num = 0;
+ /* Summary state of ADD_PATH RX for active channels */
+ uint summary_add_path_rx = 0;
+
WALK_LIST(c, p->p.channels)
{
const struct bgp_af_caps *loc = bgp_find_af_caps(local, c->afi);
@@ -586,6 +589,9 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
c->add_path_rx = (loc->add_path & BGP_ADD_PATH_RX) && (rem->add_path & BGP_ADD_PATH_TX);
c->add_path_tx = (loc->add_path & BGP_ADD_PATH_TX) && (rem->add_path & BGP_ADD_PATH_RX);
+ if (active)
+ summary_add_path_rx |= !c->add_path_rx ? 1 : 2;
+
/* Update RA mode */
if (c->add_path_tx)
c->c.ra_mode = RA_ANY;
@@ -598,6 +604,7 @@ bgp_conn_enter_established_state(struct bgp_conn *conn)
p->afi_map = mb_alloc(p->p.pool, num * sizeof(u32));
p->channel_map = mb_alloc(p->p.pool, num * sizeof(void *));
p->channel_count = num;
+ p->summary_add_path_rx = summary_add_path_rx;
WALK_LIST(c, p->p.channels)
{
diff --git a/proto/bgp/bgp.h b/proto/bgp/bgp.h
index 6f0a5587..2729780c 100644
--- a/proto/bgp/bgp.h
+++ b/proto/bgp/bgp.h
@@ -266,6 +266,7 @@ struct bgp_proto {
u8 llgr_ready; /* Neighbor could do Long-lived GR, implies gr_ready */
u8 gr_active_num; /* Neighbor is doing GR, number of active channels */
u8 channel_count; /* Number of active channels */
+ u8 summary_add_path_rx; /* Summary state of ADD_PATH RX w.r.t active channels */
u32 *afi_map; /* Map channel index -> AFI */
struct bgp_channel **channel_map; /* Map channel index -> channel */
struct bgp_conn *conn; /* Connection we have established */
@@ -361,6 +362,7 @@ struct bgp_write_state {
struct bgp_channel *channel;
struct linpool *pool;
+ int mp_reach;
int as4_session;
int add_path;
int mpls;
@@ -538,7 +540,7 @@ void bgp_get_route_info(struct rte *, byte *buf);
/* packets.c */
-void mrt_dump_bgp_state_change(struct bgp_conn *conn, unsigned old, unsigned new);
+void bgp_dump_state_change(struct bgp_conn *conn, uint old, uint new);
const struct bgp_af_desc *bgp_get_af_desc(u32 afi);
const struct bgp_af_caps *bgp_find_af_caps(struct bgp_caps *caps, u32 afi);
void bgp_schedule_packet(struct bgp_conn *conn, struct bgp_channel *c, int type);
diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index ed1db04b..3be48c00 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -17,7 +17,7 @@
#include "nest/protocol.h"
#include "nest/route.h"
#include "nest/attrs.h"
-#include "nest/mrtdump.h"
+#include "proto/mrt/mrt.h"
#include "conf/conf.h"
#include "lib/unaligned.h"
#include "lib/flowspec.h"
@@ -90,91 +90,71 @@ get_af4(byte *buf)
return (get_u16(buf) << 16) | buf[3];
}
-/*
- * MRT Dump format is not semantically specified.
- * We will use these values in appropriate fields:
- *
- * Local AS, Remote AS - configured AS numbers for given BGP instance.
- * Local IP, Remote IP - IP addresses of the TCP connection (0 if no connection)
- *
- * We dump two kinds of MRT messages: STATE_CHANGE (for BGP state
- * changes) and MESSAGE (for received BGP messages).
- *
- * STATE_CHANGE uses always AS4 variant, but MESSAGE uses AS4 variant
- * only when AS4 session is established and even in that case MESSAGE
- * does not use AS4 variant for initial OPEN message. This strange
- * behavior is here for compatibility with Quagga and Bgpdump,
- */
-
-static byte *
-mrt_put_bgp4_hdr(byte *buf, struct bgp_conn *conn, int as4)
+static void
+init_mrt_bgp_data(struct bgp_conn *conn, struct mrt_bgp_data *d)
{
struct bgp_proto *p = conn->bgp;
- uint v4 = ipa_is_ip4(p->cf->remote_ip);
+ int p_ok = conn->state >= BS_OPENCONFIRM;
- if (as4)
- {
- put_u32(buf+0, p->remote_as);
- put_u32(buf+4, p->public_as);
- buf+=8;
- }
- else
- {
- put_u16(buf+0, (p->remote_as <= 0xFFFF) ? p->remote_as : AS_TRANS);
- put_u16(buf+2, (p->public_as <= 0xFFFF) ? p->public_as : AS_TRANS);
- buf+=4;
- }
+ memset(d, 0, sizeof(struct mrt_bgp_data));
+ d->peer_as = p->remote_as;
+ d->local_as = p->local_as;
+ d->index = (p->neigh && p->neigh->iface) ? p->neigh->iface->index : 0;
+ d->af = ipa_is_ip4(p->cf->remote_ip) ? BGP_AFI_IPV4 : BGP_AFI_IPV6;
+ d->peer_ip = conn->sk ? conn->sk->daddr : IPA_NONE;
+ d->local_ip = conn->sk ? conn->sk->saddr : IPA_NONE;
+ d->as4 = p_ok ? p->as4_session : 0;
+}
- put_u16(buf+0, (p->neigh && p->neigh->iface) ? p->neigh->iface->index : 0);
- put_u16(buf+2, v4 ? BGP_AFI_IPV4 : BGP_AFI_IPV6);
- buf+=4;
+static uint bgp_find_update_afi(byte *pos, uint len);
- if (v4)
- {
- buf = put_ip4(buf, conn->sk ? ipa_to_ip4(conn->sk->daddr) : IP4_NONE);
- buf = put_ip4(buf, conn->sk ? ipa_to_ip4(conn->sk->saddr) : IP4_NONE);
- }
- else
+static int
+bgp_estimate_add_path(struct bgp_proto *p, byte *pkt, uint len)
+{
+ /* No need to estimate it for other messages than UPDATE */
+ if (pkt[18] != PKT_UPDATE)
+ return 0;
+
+ /* 1 -> no channel, 2 -> all channels, 3 -> some channels */
+ if (p->summary_add_path_rx < 3)
+ return p->summary_add_path_rx == 2;
+
+ uint afi = bgp_find_update_afi(pkt, len);
+ struct bgp_channel *c = bgp_get_channel(p, afi);
+ if (!c)
{
- buf = put_ip6(buf, conn->sk ? ipa_to_ip6(conn->sk->daddr) : IP6_NONE);
- buf = put_ip6(buf, conn->sk ? ipa_to_ip6(conn->sk->saddr) : IP6_NONE);
+ /* Either frame error (if !afi) or unknown AFI/SAFI,
+ will be reported later in regular parsing */
+ BGP_TRACE(D_PACKETS, "MRT processing noticed invalid packet");
+ return 0;
}
- return buf;
+ return c->add_path_rx;
}
static void
-mrt_dump_bgp_packet(struct bgp_conn *conn, byte *pkt, uint len)
+bgp_dump_message(struct bgp_conn *conn, byte *pkt, uint len)
{
- byte *buf = alloca(128+len); /* 128 is enough for MRT headers */
- byte *bp = buf + MRTDUMP_HDR_LENGTH;
- int as4 = conn->bgp->as4_session;
+ struct mrt_bgp_data d;
+ init_mrt_bgp_data(conn, &d);
- bp = mrt_put_bgp4_hdr(bp, conn, as4);
- memcpy(bp, pkt, len);
- bp += len;
- mrt_dump_message(&conn->bgp->p, BGP4MP, as4 ? BGP4MP_MESSAGE_AS4 : BGP4MP_MESSAGE,
- buf, bp-buf);
-}
+ d.message = pkt;
+ d.msg_len = len;
+ d.add_path = bgp_estimate_add_path(conn->bgp, pkt, len);
-static inline u16
-convert_state(uint state)
-{
- /* Convert state from our BS_* values to values used in MRTDump */
- return (state == BS_CLOSE) ? 1 : state + 1;
+ mrt_dump_bgp_message(&d);
}
void
-mrt_dump_bgp_state_change(struct bgp_conn *conn, uint old, uint new)
+bgp_dump_state_change(struct bgp_conn *conn, uint old, uint new)
{
- byte buf[128];
- byte *bp = buf + MRTDUMP_HDR_LENGTH;
+ struct mrt_bgp_data d;
+ init_mrt_bgp_data(conn, &d);
+
+ d.old_state = old;
+ d.new_state = new;
- bp = mrt_put_bgp4_hdr(bp, conn, 1);
- put_u16(bp+0, convert_state(old));
- put_u16(bp+2, convert_state(new));
- bp += 4;
- mrt_dump_message(&conn->bgp->p, BGP4MP, BGP4MP_STATE_CHANGE_AS4, buf, bp-buf);
+ mrt_dump_bgp_state_change(&d);
}
static byte *
@@ -2135,6 +2115,7 @@ again: ;
.proto = p,
.channel = c,
.pool = bgp_linpool,
+ .mp_reach = (c->afi != BGP_AF_IPV4) || c->ext_next_hop,
.as4_session = p->as4_session,
.add_path = c->add_path_tx,
.mpls = c->desc->mpls,
@@ -2162,7 +2143,7 @@ again: ;
goto again;
}
- res = (c->afi == BGP_AF_IPV4) && !c->ext_next_hop ?
+ res = !s.mp_reach ?
bgp_create_ip_reach(&s, buck, buf, end):
bgp_create_mp_reach(&s, buck, buf, end);
@@ -2389,6 +2370,67 @@ done:
return;
}
+static uint
+bgp_find_update_afi(byte *pos, uint len)
+{
+ /*
+ * This is stripped-down version of bgp_rx_update(), bgp_decode_attrs() and
+ * bgp_decode_mp_[un]reach_nlri() used by MRT code in order to find out which
+ * AFI/SAFI is associated with incoming UPDATE. Returns 0 for framing errors.
+ */
+ if (len < 23)
+ return 0;
+
+ /* Assume there is no withrawn NLRI, read lengths and move to attribute list */
+ uint wlen = get_u16(pos + 19);
+ uint alen = get_u16(pos + 21);
+ ADVANCE(pos, len, 23);
+
+ /* Either non-zero withdrawn NLRI, non-zero reachable NLRI, or IPv4 End-of-RIB */
+ if ((wlen != 0) || (alen < len) || !alen)
+ return BGP_AF_IPV4;
+
+ if (alen > len)
+ return 0;
+
+ /* Process attribute list (alen == len) */
+ while (len)
+ {
+ if (len < 2)
+ return 0;
+
+ uint flags = pos[0];
+ uint code = pos[1];
+ ADVANCE(pos, len, 2);
+
+ uint ll = !(flags & BAF_EXT_LEN) ? 1 : 2;
+ if (len < ll)
+ return 0;
+
+ /* Read attribute length and move to attribute body */
+ alen = (ll == 1) ? get_u8(pos) : get_u16(pos);
+ ADVANCE(pos, len, ll);
+
+ if (len < alen)
+ return 0;
+
+ /* Found MP NLRI */
+ if ((code == BA_MP_REACH_NLRI) || (code == BA_MP_UNREACH_NLRI))
+ {
+ if (alen < 3)
+ return 0;
+
+ return BGP_AF(get_u16(pos), pos[2]);
+ }
+
+ /* Move to the next attribute */
+ ADVANCE(pos, len, alen);
+ }
+
+ /* No basic or MP NLRI, but there are some attributes -> error */
+ return 0;
+}
+
/*
* ROUTE-REFRESH
@@ -2890,7 +2932,7 @@ bgp_rx_packet(struct bgp_conn *conn, byte *pkt, uint len)
DBG("BGP: Got packet %02x (%d bytes)\n", type, len);
if (conn->bgp->p.mrtdump & MD_MESSAGES)
- mrt_dump_bgp_packet(conn, pkt, len);
+ bgp_dump_message(conn, pkt, len);
switch (type)
{
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 12:11:42 +0000