BMP protocol support

Initial implementation of a basic subset of the BMP (BGP Monitoring
Protocol, RFC 7854) from Akamai team. Submitted for further review
and improvement.

1 files changed, 152 insertions, 0 deletions

diff --git a/proto/bmp/bmp.h b/proto/bmp/bmp.h
new file mode 100644
index 00000000..03c5f529
--- /dev/null
+++ b/proto/bmp/bmp.h
@@ -0,0 +1,152 @@
+/*
+ *	BIRD -- The BGP Monitoring Protocol (BMP)
+ *
+ *	(c) 2020 Akamai Technologies, Inc. (Pawel Maslanka, pmaslank@akamai.com)
+ *
+ *	Can be freely distributed and used under the terms of the GNU GPL.
+ */
+
+#ifndef _BIRD_BMP_H_
+#define _BIRD_BMP_H_
+
+#include "nest/bird.h"
+#include "nest/protocol.h"
+#include "lib/lists.h"
+#include "nest/route.h"
+#include "lib/event.h"
+#include "lib/hash.h"
+#include "lib/socket.h"
+#include "proto/bmp/map.h"
+
+#include <stdbool.h>
+
+// Max length of MIB-II description object
+#define MIB_II_STR_LEN 255
+
+enum bmp_peer_down {
+  // Value of packet size of 'pkt_size' argument of bmp_peer_down() function
+  // used for pointing out that there was not any packet to pass
+  BMP_PEER_DOWN_NULL_PKT_SIZE = 0
+};
+
+// The following fields of this structure controls whether there will be put
+// specific routes into Route Monitoring message and send to BMP collector
+struct monitoring_rib {
+  bool in_pre_policy;  // Monitoring pre-policy Adj-Rib-In
+  bool in_post_policy; // Monitoring post-policy Adj-Rib-In
+  bool local;          // Monitoring Local Rib
+};
+
+struct bmp_config {
+  struct proto_config c;
+  char *sys_descr;                    // sysDescr MIB-II [RFC1213] object
+  char *sys_name;                     // sysName MIB-II [RFC1213] object
+  ip_addr station_ip;                 // Monitoring station address
+  u16 station_port;                   // Monitoring station TCP port
+  bool disabled;                      // Manually disabled
+  bool monitoring_rib_in_pre_policy;  // Route monitoring pre-policy Adj-Rib-In
+  bool monitoring_rib_in_post_policy; // Route monitoring post-policy Adj-Rib-In
+  bool monitoring_rib_local;          // Route monitoring Local Rib
+};
+
+/* Forward declarations */
+struct bgp_proto;
+struct bmp_proto;
+
+struct bmp_conn {
+  struct bmp_proto *bmp;
+  struct birdsock *sk;
+  event *tx_ev;
+};
+
+// Stores sent and received BGP OPEN MSGs
+struct bmp_peer_open_msg {
+  struct bmp_peer_map tx_msg;
+  struct bmp_peer_map rx_msg;
+};
+
+// Keeps necessary information during composing BGP UPDATE MSG which is going
+// to be sent to the BMP collector
+struct rt_table_info {
+  list update_msg_queue;         // Stores all composed BGP UPDATE MSGs
+  size_t update_msg_size;        // Size of all BGP UPDATE MSGs
+  struct timeval update_begin_time; // Keeps timestamp of starting BGP UPDATE MSGs composing
+  bool update_in_progress;       // Holds information whether composing process is still in progress
+};
+
+struct bmp_proto {
+  struct proto p;                  // Parent proto
+  const struct bmp_config *cf;     // Shortcut to BMP configuration
+  struct bmp_conn *conn;           // Connection we have established
+  char sys_descr[MIB_II_STR_LEN];  // sysDescr MIB-II [RFC1213] object
+  char sys_name[MIB_II_STR_LEN];   // sysName MIB-II [RFC1213] object
+  ip_addr station_ip;              // Monitoring station IP address
+  u16 station_port;                // Monitoring station TCP port
+  bool disabled;                   // Manually disabled
+  struct monitoring_rib monitoring_rib;
+  // Below fields are for internal use
+  int station_socket;              // Socket associated with the BMP collector
+  struct bmp_peer_map bgp_peers;   // Stores 'bgp_proto' structure per BGP peer
+  struct bmp_peer_open_msg peer_open_msg; // Stores sent and received BGP OPEN MSG per BGP peer
+  pool *buffer_mpool;              // Memory pool used for BMP buffer allocations
+  pool *map_mem_pool;              // Memory pool used for BMP map allocations
+  pool *tx_mem_pool;               // Memory pool used for packet allocations designated to BMP collector
+  pool *update_msg_mem_pool;       // Memory pool used for BPG UPDATE MSG allocations
+  list tx_queue;                   // Stores queued packets going to be sent
+  timer *connect_retry_timer;      // Timer for retrying connection to the BMP collector
+  struct rt_table_info rt_table_in_pre_policy; // Pre-policy route import table
+  bool station_connected;          // Flag that stores connection status with BMP station
+  bool started;                    // Flag that stores running status of BMP instance
+};
+
+/**
+ * bmp_put_sent_bgp_open_msg - save sent BGP OPEN msg packet in BMP implementation.
+ * NOTE: If there has been passed sent and received BGP OPEN MSGs to the BMP
+ *       implementation, then there is going to be send BMP Peer Up Notification
+ *       message to the BMP collector.
+ */
+void
+bmp_put_sent_bgp_open_msg(const struct bgp_proto *bgp, const byte* pkt,
+  const size_t pkt_size);
+
+/**
+ * bmp_put_recv_bgp_open_msg - save received BGP OPEN msg packet in BMP implementation.
+ * NOTE: If there has been passed sent and received BGP OPEN MSGs to the BMP
+ *       implementation, then there is going to be send BMP Peer Up Notification
+ *       message to the BMP collector.
+ */
+void
+bmp_put_recv_bgp_open_msg(const struct bgp_proto *bgp, const byte* pkt,
+  const size_t pkt_size);
+
+/**
+ * The following 4 functions create BMP Route Monitoring message based on
+ * pre-policy Adj-RIB-In. Composing Route Monitoring message consist of few
+ * stages. First of all call bmp_route_monitor_update_in_pre_begin() in order
+ * to start composing message. As a second step, call
+ * bmp_route_monitor_put_update_in_pre_msg() in order to save BGP UPDATE msg.
+ * As a third step call bmp_route_monitor_update_in_pre_commit() in order to
+ * send BMP Route Monitoring message to the BMP collector. As a last step,
+ * call bmp_route_monitor_update_in_pre_end() in order to release resources.
+ */
+void
+bmp_route_monitor_update_in_pre_begin(void);
+
+void
+bmp_route_monitor_put_update_in_pre_msg(const byte *data, const size_t data_size);
+
+void
+bmp_route_monitor_update_in_pre_commit(const struct bgp_proto *bgp);
+
+void
+bmp_route_monitor_update_in_pre_end(void);
+
+/**
+ * bmp_peer_down - send notification that BGP peer connection is not in
+ * established state
+ */
+void
+bmp_peer_down(const struct bgp_proto *bgp, const int err_class, const byte *pkt,
+  size_t pkt_size);
+
+#endif	/* _BIRD_BMP_H_ */