bgpd: BMP Loc-Rib Monitoring (RFC9069) Implementation

bgpd/bgp_bmp.h

@@ -124,6 +124,7 @@ struct bmp {
 	 * ahead we need to make sure that refcount is decremented.  Also, on
 	 * disconnects we need to walk the queue and drop our reference.
 	 */
+	struct bmp_queue_entry *locrib_queuepos;
 	struct bmp_queue_entry *queuepos;
 	struct bmp_mirrorq *mirrorpos;
 	bool mirror_lost;
@@ -215,12 +216,14 @@ struct bmp_targets {
 	int stat_msec;
 
 	/* only supporting:
-	 * - IPv4 / unicast & multicast
-	 * - IPv6 / unicast & multicast
+	 * - IPv4 / unicast & multicast & VPN
+	 * - IPv6 / unicast & multicast & VPN
 	 * - L2VPN / EVPN
 	 */
 #define BMP_MON_PREPOLICY	(1 << 0)
 #define BMP_MON_POSTPOLICY	(1 << 1)
+#define BMP_MON_LOC_RIB (1 << 2)
+
 	uint8_t afimon[AFI_MAX][SAFI_MAX];
 	bool mirror;
 
@@ -232,6 +235,9 @@ struct bmp_targets {
 	struct bmp_qhash_head updhash;
 	struct bmp_qlist_head updlist;
 
+	struct bmp_qhash_head locupdhash;
+	struct bmp_qlist_head locupdlist;
+
 	uint64_t cnt_accept, cnt_aclrefused;
 
 	QOBJ_FIELDS;

bgpd/bgp_route.c

@@ -85,6 +85,11 @@ DEFINE_HOOK(bgp_rpki_prefix_status,
 	     const struct prefix *prefix),
 	    (peer, attr, prefix));
 
+DEFINE_HOOK(bgp_route_update,
+	    (struct bgp *bgp, afi_t afi, safi_t safi, struct bgp_dest *bn,
+	     struct bgp_path_info *old_route, struct bgp_path_info *new_route),
+	    (bgp, afi, safi, bn, old_route, new_route));
+
 /* Extern from bgp_dump.c */
 extern const char *bgp_origin_str[];
 extern const char *bgp_origin_long_str[];
@@ -3435,6 +3440,7 @@ static void bgp_process_main_one(struct bgp *bgp, struct bgp_dest *dest,
 				&bgp->t_rmap_def_originate_eval);
 	}
 
+	/* TODO BMP insert rib update hook */
 	if (old_select)
 		bgp_path_info_unset_flag(dest, old_select, BGP_PATH_SELECTED);
 	if (new_select) {
@@ -3447,6 +3453,15 @@ static void bgp_process_main_one(struct bgp *bgp, struct bgp_dest *dest,
 		UNSET_FLAG(new_select->flags, BGP_PATH_LINK_BW_CHG);
 	}
 
+	/* call bmp hook for loc-rib route update / withdraw after flags were
+	 * set
+	 */
+	if (old_select || new_select) {
+		hook_call(bgp_route_update, bgp, afi, safi, dest, old_select,
+			  new_select);
+	}
+
+
 #ifdef ENABLE_BGP_VNC
 	if ((afi == AFI_IP || afi == AFI_IP6) && (safi == SAFI_UNICAST)) {
 		if (old_select != new_select) {

bgpd/bgp_route.h

@@ -211,6 +211,9 @@ struct bgp_path_info_extra {
 	mpls_label_t label[BGP_MAX_LABELS];
 	uint32_t num_labels;
 
+	/* timestamp of the rib installation */
+	time_t bgp_rib_uptime;
+
 	/*For EVPN*/
 	struct bgp_path_info_extra_evpn *evpn;
 
@@ -674,6 +677,12 @@ DECLARE_HOOK(bgp_process,
 	      struct peer *peer, bool withdraw),
 	     (bgp, afi, safi, bn, peer, withdraw));
 
+/* called when a route is updated in the rib */
+DECLARE_HOOK(bgp_route_update,
+	     (struct bgp *bgp, afi_t afi, safi_t safi, struct bgp_dest *bn,
+	      struct bgp_path_info *old_route, struct bgp_path_info *new_route),
+	     (bgp, afi, safi, bn, old_route, new_route));
+
 /* BGP show options */
 #define BGP_SHOW_OPT_JSON (1 << 0)
 #define BGP_SHOW_OPT_WIDE (1 << 1)

bgpd/bgp_trace.h

@@ -135,11 +135,12 @@ TRACEPOINT_LOGLEVEL(frr_bgp, bmp_mirror_packet, TRACE_INFO)
 TRACEPOINT_EVENT(
 	frr_bgp,
 	bmp_eor,
-	TP_ARGS(afi_t, afi, safi_t, safi, uint8_t, flags),
+	TP_ARGS(afi_t, afi, safi_t, safi, uint8_t, flags, peer_type_flag),
 	TP_FIELDS(
 		ctf_integer(afi_t, afi, afi)
 		ctf_integer(safi_t, safi, safi)
 		ctf_integer(uint8_t, flags, flags)
+		ctf_integer(uint8_t, peer_type_flag, peer_type_flag)
 	)
 )
 

doc/developer/bmp.rst

@@ -0,0 +1,49 @@
+.. _bmp:
+
+***
+BMP
+***
+
+RFC 7854
+========
+Missing features (non exhaustive):
+  - Per-Peer Header
+
+    - Peer Type Flag
+    - Peer Distingsher
+
+  - Peer Up
+
+    - Reason codes (according to TODO comments in code)
+
+Peer Type Flag and Peer Distinguisher can be implemented easily using RFC 9069's base code.
+
+RFC 9069
+========
+Everything that isn't listed here is implemented and should be working.
+Missing features (should be exhaustive):
+
+- Per-Peer Header
+
+  - Timestamp
+
+    - set to 0
+    - value is now saved `struct bgp_path_info -> locrib_uptime`
+    - needs testing
+
+- Peer Up/Down
+
+  - VRF/Table Name TLV
+
+    - code for TLV exists
+    - need better RFC understanding
+
+- Peer Down Only
+
+  - Reason code (bc not supported in RFC 7854 either)
+
+- Statistics Report
+
+  - Stat Type = 8: (64-bit Gauge) Number of routes in Loc-RIB.
+  - Stat Type = 10: Number of routes in per-AFI/SAFI Loc-RIB. The value is
+    structured as: 2-byte AFI, 1-byte SAFI, followed by a 64-bit Gauge.

doc/developer/subdir.am

@@ -5,6 +5,7 @@
 dev_RSTFILES = \
 	doc/developer/bgp-typecodes.rst \
 	doc/developer/bgpd.rst \
+	doc/developer/bmp.rst \
 	doc/developer/building-frr-for-alpine.rst \
 	doc/developer/building-frr-for-archlinux.rst \
 	doc/developer/building-frr-for-centos6.rst \

doc/user/bmp.rst

@@ -36,8 +36,8 @@ The `BMP` implementation in FRR has the following properties:
   successfully.  OPEN messages for failed sessions cannot currently be
   mirrored.
 
-- **route monitoring** is available for IPv4 and IPv6 AFIs, unicast and
-  multicast SAFIs.  Other SAFIs (VPN, Labeled-Unicast, Flowspec, etc.) are not
+- **route monitoring** is available for IPv4 and IPv6 AFIs, unicast, multicast,
+  EVPN and VPN SAFIs. Other SAFIs (VPN, Labeled-Unicast, Flowspec, etc.) are not
   currently supported.
 
 - monitoring peers that have BGP **add-path** enabled on the session will
@@ -146,10 +146,10 @@ associated with a particular ``bmp targets``:
    Send BMP Statistics (counter) messages at the specified interval (in
    milliseconds.)
 
-.. clicmd:: bmp monitor AFI SAFI <pre-policy|post-policy>
+.. clicmd:: bmp monitor AFI SAFI <pre-policy|post-policy|loc-rib>
 
    Perform Route Monitoring for the specified AFI and SAFI.  Only IPv4 and
-   IPv6 are currently valid for AFI. SAFI valid values are currently 
+   IPv6 are currently valid for AFI. SAFI valid values are currently
    unicast, multicast, evpn and vpn.
    Other AFI/SAFI combinations may be added in the future.
 

tests/topotests/bgp_bmp/test_bgp_bmp.py

@@ -49,6 +49,7 @@
 
 PRE_POLICY = "pre-policy"
 POST_POLICY = "post-policy"
+LOC_RIB = "loc-rib"
 
 
 def build_topo(tgen):
@@ -120,7 +121,7 @@ def get_bmp_messages():
     return messages
 
 
-def check_for_prefixes(expected_prefixes, bmp_log_type, post_policy):
+def check_for_prefixes(expected_prefixes, bmp_log_type, policy):
     """
     Check for the presence of the given prefixes in the BMP server logs with
     the given message type and the set policy.
@@ -138,7 +139,7 @@ def check_for_prefixes(expected_prefixes, bmp_log_type, post_policy):
         if "ip_prefix" in m.keys()
         and "bmp_log_type" in m.keys()
         and m["bmp_log_type"] == bmp_log_type
-        and m["post_policy"] == post_policy
+        and m["policy"] == policy
     ]
 
     # check for prefixes
@@ -202,15 +203,15 @@ def unicast_prefixes(policy):
 
     logger.info("checking for updated prefixes")
     # check
-    test_func = partial(check_for_prefixes, prefixes, "update", policy == POST_POLICY)
+    test_func = partial(check_for_prefixes, prefixes, "update", policy)
     success, _ = topotest.run_and_expect(test_func, True, wait=0.5)
     assert success, "Checking the updated prefixes has been failed !."
 
     # withdraw prefixes
     configure_prefixes(tgen, "r2", 65502, "unicast", prefixes, update=False)
     logger.info("checking for withdrawed prefxies")
     # check
-    test_func = partial(check_for_prefixes, prefixes, "withdraw", policy == POST_POLICY)
+    test_func = partial(check_for_prefixes, prefixes, "withdraw", policy)
     success, _ = topotest.run_and_expect(test_func, True, wait=0.5)
     assert success, "Checking the withdrawed prefixes has been failed !."
 
@@ -239,6 +240,8 @@ def test_bmp_bgp_unicast():
     unicast_prefixes(PRE_POLICY)
     logger.info("*** Unicast prefixes post-policy logging ***")
     unicast_prefixes(POST_POLICY)
+    logger.info("*** Unicast prefixes loc-rib logging ***")
+    unicast_prefixes(LOC_RIB)
 
 
 if __name__ == "__main__":

tests/topotests/lib/bmp_collector/bmp.py

@@ -252,14 +252,15 @@ def dissect(cls, data):
 
         if peer_type == 0x03:
             msg['is_filtered'] = bool(peer_flags & IS_FILTERED)
+            msg['policy'] = 'loc-rib'
         else:
             # peer_flags = 0x0000 0000
             # ipv6, post-policy, as-path, adj-rib-out, reserverdx4
             is_adj_rib_out = bool(peer_flags & IS_ADJ_RIB_OUT)
             is_as_path = bool(peer_flags & IS_AS_PATH)
             is_post_policy = bool(peer_flags & IS_POST_POLICY)
             is_ipv6 = bool(peer_flags & IS_IPV6)
-            msg['post_policy'] = is_post_policy
+            msg['policy'] = 'post-policy' if is_post_policy else 'pre-policy'
             msg['ipv6'] = is_ipv6
             msg['peer_ip'] = bin2str_ipaddress(peer_address, is_ipv6)