bgpd: bmp loc-rib RFC9069 compliant monitoring messages

set field peer bgp id to the peer's remote id in every case except loc-rib (RFC9069 case) in which we put the bgp instance's router-id if available or 0-filled if not available
set field peer asn to local primary bgp asn in case of loc-rib instance (RFC9069) else it's set to the peer's asn
set field peer address to 0 in loc-rib instance (RFC9069 case) and to the peer's address in other cases
had to pass struct bgp reference to bmp_per_peer_hdr to access router-id and such, but it's always safely accessed when used

Signed-off-by: Maxence Younsi <mx.yns@outlook.fr>

diff --git a/bgpd/bgp_bmp.c b/bgpd/bgp_bmp.c
index 2cce7f84f5ceaed8adf7d8d93e20dfc1ea4c436c..e75f08eaff0ff41ed8a682881d46563aabe9a651 100644 (file)
--- a/bgpd/bgp_bmp.c
+++ b/bgpd/bgp_bmp.c
@@ -243,15 +243,16 @@ static void bmp_free(struct bmp *bmp)
 static uint64_t bmp_get_peer_distinguisher(struct bmp *bmp, afi_t afi)
 {
 
-       // legacy : TODO should be turned into an option at some point
-       // return bmp->targets->bgp->vrf_id;
+       /* legacy : TODO should be turned into an option at some point
+        * return bmp->targets->bgp->vrf_id;
+        */
        struct bgp *bgp = bmp->targets->bgp;
        struct prefix_rd *prd = &bgp->vpn_policy[afi].tovpn_rd;
        /*
         * default vrf => can't have RD => 0
         * vrf => has RD?
-        *              if yes => use RD value
-        *              else => use vrf_id and convert it so that
+        *              if yes => use RD value
+        *              else => use vrf_id and convert it so that
         * peer_distinguisher is 0::vrf_id
         */
        return bgp->inst_type == VRF_DEFAULT ? 0
@@ -266,7 +267,7 @@ static void bmp_common_hdr(struct stream *s, uint8_t ver, uint8_t type)
        stream_putc(s, type);
 }
 
-static void bmp_per_peer_hdr(struct stream *s, struct peer *peer, uint8_t flags,
+static void bmp_per_peer_hdr(struct stream *s, struct bgp* bgp, struct peer *peer, uint8_t flags,
                             uint8_t peer_type_flag,
                             uint64_t peer_distinguisher,
                             const struct timeval *tv)
@@ -281,6 +282,8 @@ static void bmp_per_peer_hdr(struct stream *s, struct peer *peer, uint8_t flags,
 #define BMP_PEER_FLAG_L (1 << 6)
 #define BMP_PEER_FLAG_A (1 << 5)
 
+       bool is_locrib = peer_type_flag == BMP_PEER_TYPE_LOC_RIB_INSTANCE;
+
        /* Peer Type */
        stream_putc(s, peer_type_flag);
 
@@ -295,25 +298,32 @@ static void bmp_per_peer_hdr(struct stream *s, struct peer *peer, uint8_t flags,
        stream_put(s, (uint8_t *)&peer_distinguisher, 8);
 
        /* Peer Address */
-       if (peer->connection->su.sa.sa_family == AF_INET6)
-               stream_put(s, &peer->connection->su.sin6.sin6_addr, 16);
-       else if (peer->connection->su.sa.sa_family == AF_INET) {
+       /* Set to 0 if it's a LOC-RIB INSTANCE (RFC 9069) or if it's not an IPv4/6 address */
+       if (is_locrib
+           || (peer->connection->su.sa.sa_family != AF_INET6 && peer->connection->su.sa.sa_family != AF_INET)) {
                stream_putl(s, 0);
                stream_putl(s, 0);
                stream_putl(s, 0);
-               stream_put_in_addr(s, &peer->connection->su.sin.sin_addr);
-       } else {
                stream_putl(s, 0);
+       } else if (peer->connection->su.sa.sa_family == AF_INET6)
+               stream_put(s, &peer->connection->su.sin6.sin6_addr, 16);
+       else if (peer->connection->su.sa.sa_family == AF_INET) {
                stream_putl(s, 0);
                stream_putl(s, 0);
                stream_putl(s, 0);
+               stream_put_in_addr(s, &peer->connection->su.sin.sin_addr);
        }
 
        /* Peer AS */
-       stream_putl(s, peer->as);
+       /* set peer ASN but for LOC-RIB INSTANCE (RFC 9069) put the local bgp ASN if available or 0 */
+       as_t asn = !is_locrib ? peer->as : bgp ? bgp->as : 0L;
+       stream_putl(s, asn);
 
        /* Peer BGP ID */
-       stream_put_in_addr(s, &peer->remote_id);
+       /* set router-id but for LOC-RIB INSTANCE (RFC 9069) put the instance router-id if available or 0 */
+       struct in_addr* bgp_id = !is_locrib ? &peer->remote_id : bgp ? &bgp->router_id : NULL;
+       zlog_info("bmp: per peer header is_locrib=%d, peer->remote_id=%pI4, bgp->router_id=%pI4, selected=%pI4", is_locrib, &peer->remote_id, &bgp->router_id, bgp_id);
+       stream_put_in_addr(s, bgp_id);
 
        /* Timestamp */
        if (tv) {
@@ -395,7 +405,7 @@ static struct stream *bmp_peerstate(struct peer *peer, bool down)
 
                bmp_common_hdr(s, BMP_VERSION_3,
                                BMP_TYPE_PEER_UP_NOTIFICATION);
-               bmp_per_peer_hdr(s, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
+               bmp_per_peer_hdr(s, peer->bgp, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
                                 &uptime_real);
 
                /* Local Address (16 bytes) */
@@ -449,7 +459,7 @@ static struct stream *bmp_peerstate(struct peer *peer, bool down)
 
                bmp_common_hdr(s, BMP_VERSION_3,
                                BMP_TYPE_PEER_DOWN_NOTIFICATION);
-               bmp_per_peer_hdr(s, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
+               bmp_per_peer_hdr(s, peer->bgp, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
                                 &uptime_real);
 
                type_pos = stream_get_endp(s);
@@ -640,7 +650,7 @@ static void bmp_wrmirror_lost(struct bmp *bmp, struct pullwr *pullwr)
        s = stream_new(BGP_MAX_PACKET_SIZE);
 
        bmp_common_hdr(s, BMP_VERSION_3, BMP_TYPE_ROUTE_MIRRORING);
-       bmp_per_peer_hdr(s, bmp->targets->bgp->peer_self, 0,
+       bmp_per_peer_hdr(s, bmp->targets->bgp, bmp->targets->bgp->peer_self, 0,
                         BMP_PEER_TYPE_GLOBAL_INSTANCE, 0, &tv);
 
        stream_putw(s, BMP_MIRROR_TLV_TYPE_INFO);
@@ -679,7 +689,7 @@ static bool bmp_wrmirror(struct bmp *bmp, struct pullwr *pullwr)
        s = stream_new(BGP_MAX_PACKET_SIZE);
 
        bmp_common_hdr(s, BMP_VERSION_3, BMP_TYPE_ROUTE_MIRRORING);
-       bmp_per_peer_hdr(s, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
+       bmp_per_peer_hdr(s, bmp->targets->bgp, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
                         &bmq->tv);
 
        /* BMP Mirror TLV. */
@@ -831,7 +841,7 @@ static void bmp_eor(struct bmp *bmp, afi_t afi, safi_t safi, uint8_t flags, uint
 
                bmp_common_hdr(s2, BMP_VERSION_3,
                                BMP_TYPE_ROUTE_MONITORING);
-               bmp_per_peer_hdr(s2, peer, flags, peer_type_flag, 0, NULL);
+               bmp_per_peer_hdr(s2, bmp->targets->bgp, peer, flags, peer_type_flag, 0, NULL);
 
                stream_putl_at(s2, BMP_LENGTH_POS,
                                stream_get_endp(s) + stream_get_endp(s2));
@@ -954,7 +964,7 @@ static void bmp_monitor(struct bmp *bmp, struct peer *peer, uint8_t flags,
 
        hdr = stream_new(BGP_MAX_PACKET_SIZE);
        bmp_common_hdr(hdr, BMP_VERSION_3, BMP_TYPE_ROUTE_MONITORING);
-       bmp_per_peer_hdr(hdr, peer, flags, peer_type_flags, peer_distinguisher_flag, &uptime_real);
+       bmp_per_peer_hdr(hdr, bmp->targets->bgp, peer, flags, peer_type_flags, peer_distinguisher_flag, &uptime_real);
 
        stream_putl_at(hdr, BMP_LENGTH_POS,
                        stream_get_endp(hdr) + stream_get_endp(msg));
@@ -1535,7 +1545,7 @@ static void bmp_stats(struct event *thread)
 
                s = stream_new(BGP_MAX_PACKET_SIZE);
                bmp_common_hdr(s, BMP_VERSION_3, BMP_TYPE_STATISTICS_REPORT);
-               bmp_per_peer_hdr(s, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
+               bmp_per_peer_hdr(s, bt->bgp, peer, 0, BMP_PEER_TYPE_GLOBAL_INSTANCE, 0,
                                 &tv);
 
                count_pos = stream_get_endp(s);