text: /* BGP attributes.
   * Copyright (C) 1996, 97, 98 Kunihiro Ishiguro
   *
   * This file is part of GNU Zebra.
   *
   * GNU Zebra is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License as published by the
   * Free Software Foundation; either version 2, or (at your option) any
   * later version.
   *
   * GNU Zebra is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License along
   * with this program; see the file COPYING; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  #ifndef _QUAGGA_BGP_ATTR_H
  #define _QUAGGA_BGP_ATTR_H
  
  #include "mpls.h"
  #include "bgp_attr_evpn.h"
  #include "bgpd/bgp_encap_types.h"
  #include "srte.h"
  
  /* Simple bit mapping. */
  #define BITMAP_NBBY 8
  
  #define SET_BITMAP(MAP, NUM)                                                   \
  	SET_FLAG(MAP[(NUM) / BITMAP_NBBY], 1 << ((NUM) % BITMAP_NBBY))
  
  #define CHECK_BITMAP(MAP, NUM)                                                 \
  	CHECK_FLAG(MAP[(NUM) / BITMAP_NBBY], 1 << ((NUM) % BITMAP_NBBY))
  
  #define BGP_MED_MAX UINT32_MAX
  
  /* BGP Attribute type range. */
  #define BGP_ATTR_TYPE_RANGE     256
  #define BGP_ATTR_BITMAP_SIZE    (BGP_ATTR_TYPE_RANGE / BITMAP_NBBY)
  
  /* BGP Attribute flags. */
  #define BGP_ATTR_FLAG_OPTIONAL  0x80	/* Attribute is optional. */
  #define BGP_ATTR_FLAG_TRANS     0x40	/* Attribute is transitive. */
  #define BGP_ATTR_FLAG_PARTIAL   0x20	/* Attribute is partial. */
  #define BGP_ATTR_FLAG_EXTLEN    0x10	/* Extended length flag. */
  
  /* BGP attribute header must bigger than 2. */
  #define BGP_ATTR_MIN_LEN        3       /* Attribute flag, type length. */
  #define BGP_ATTR_DEFAULT_WEIGHT 32768
  
  /* Valid lengths for mp_nexthop_len */
  #define BGP_ATTR_NHLEN_IPV4               IPV4_MAX_BYTELEN
  #define BGP_ATTR_NHLEN_VPNV4              8+IPV4_MAX_BYTELEN
  #define BGP_ATTR_NHLEN_IPV6_GLOBAL        IPV6_MAX_BYTELEN
  #define BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL (IPV6_MAX_BYTELEN * 2)
  #define BGP_ATTR_NHLEN_VPNV6_GLOBAL       8+IPV6_MAX_BYTELEN
  #define BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL ((8+IPV6_MAX_BYTELEN) * 2)
  
  /* Prefix SID types */
  #define BGP_PREFIX_SID_LABEL_INDEX     1
  #define BGP_PREFIX_SID_IPV6            2
  #define BGP_PREFIX_SID_ORIGINATOR_SRGB 3
  #define BGP_PREFIX_SID_VPN_SID 4
  #define BGP_PREFIX_SID_SRV6_L3_SERVICE 5
  #define BGP_PREFIX_SID_SRV6_L2_SERVICE 6
  
  #define BGP_PREFIX_SID_LABEL_INDEX_LENGTH      7
  #define BGP_PREFIX_SID_IPV6_LENGTH            19
  #define BGP_PREFIX_SID_ORIGINATOR_SRGB_LENGTH  6
  #define BGP_PREFIX_SID_VPN_SID_LENGTH         19
  
  /* SRv6 Service Sub-TLV types */
  #define BGP_PREFIX_SID_SRV6_L3_SERVICE_SID_INFO 1
  #define BGP_PREFIX_SID_SRV6_L3_SERVICE_SID_INFO_LENGTH 21
  
  /* SRv6 Service Data Sub-Sub-TLV types */
  #define BGP_PREFIX_SID_SRV6_L3_SERVICE_SID_STRUCTURE 1
  #define BGP_PREFIX_SID_SRV6_L3_SERVICE_SID_STRUCTURE_LENGTH 6
  
  /* SRv6 SID Structure default values */
  #define BGP_PREFIX_SID_SRV6_LOCATOR_BLOCK_LENGTH 40
  #define BGP_PREFIX_SID_SRV6_LOCATOR_NODE_LENGTH 24
  #define BGP_PREFIX_SID_SRV6_FUNCTION_LENGTH 16
  #define BGP_PREFIX_SID_SRV6_ARGUMENT_LENGTH 0
  #define BGP_PREFIX_SID_SRV6_TRANSPOSITION_LENGTH 16
  #define BGP_PREFIX_SID_SRV6_TRANSPOSITION_OFFSET 64
  
  #define BGP_ATTR_NH_AFI(afi, attr) \
  	((afi != AFI_L2VPN) ? afi : \
  	((attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV4) ? AFI_IP : AFI_IP6))
  
  /* PMSI tunnel types (RFC 6514) */
  
  struct bgp_attr_encap_subtlv {
  	struct bgp_attr_encap_subtlv *next; /* for chaining */
  	/* Reference count of this attribute. */
  	unsigned long refcnt;
  	uint16_t type;
  	uint16_t length;
  	uint8_t value[0]; /* will be extended */
  };
  
  #ifdef ENABLE_BGP_VNC
  /*
   * old rfp<->rfapi representation
   */
  struct bgp_tea_options {
  	struct bgp_tea_options *next;
  	uint8_t options_count;
  	uint16_t options_length; /* each TLV may be 256 in length */
  	uint8_t type;
  	uint8_t length;
  	void *value; /* pointer to data */
  };
  
  #endif
  
  enum pta_type {
  	PMSI_TNLTYPE_NO_INFO = 0,
  	PMSI_TNLTYPE_RSVP_TE_P2MP,
  	PMSI_TNLTYPE_MLDP_P2MP,
  	PMSI_TNLTYPE_PIM_SSM,
  	PMSI_TNLTYPE_PIM_SM,
  	PMSI_TNLTYPE_PIM_BIDIR,
  	PMSI_TNLTYPE_INGR_REPL,
  	PMSI_TNLTYPE_MLDP_MP2MP,
  	PMSI_TNLTYPE_MAX = PMSI_TNLTYPE_MLDP_MP2MP
  };
  
  /*
   * Prefix-SID type-4
   * SRv6-VPN-SID-TLV
   * draft-dawra-idr-srv6-vpn-04
   */
  struct bgp_attr_srv6_vpn {
  	unsigned long refcnt;
  	uint8_t sid_flags;
  	struct in6_addr sid;
  };
  
  /*
   * Prefix-SID type-5
   * SRv6-L3VPN-Service-TLV
   * draft-dawra-idr-srv6-vpn-05
   */
  struct bgp_attr_srv6_l3vpn {
  	unsigned long refcnt;
  	uint8_t sid_flags;
  	uint16_t endpoint_behavior;
  	struct in6_addr sid;
  	uint8_t loc_block_len;
  	uint8_t loc_node_len;
  	uint8_t func_len;
  	uint8_t arg_len;
  	uint8_t transposition_len;
  	uint8_t transposition_offset;
  };
  
  /* BGP core attribute structure. */
  struct attr {
  	/* AS Path structure */
  	struct aspath *aspath;
  
  	/* Community structure */
  	struct community *community;
  
  	/* Reference count of this attribute. */
  	unsigned long refcnt;
  
  	/* Flag of attribute is set or not. */
  	uint64_t flag;
  
  	/* Apart from in6_addr, the remaining static attributes */
  	struct in_addr nexthop;
  	uint32_t med;
  	uint32_t local_pref;
  	ifindex_t nh_ifindex;
  
  	/* Path origin attribute */
  	uint8_t origin;
  
  	/* PMSI tunnel type (RFC 6514). */
  	enum pta_type pmsi_tnl_type;
  
  	/* has the route-map changed any attribute?
  	   Used on the peer outbound side. */
  	uint32_t rmap_change_flags;
  
  	/* Multi-Protocol Nexthop, AFI IPv6 */
  	struct in6_addr mp_nexthop_global;
  	struct in6_addr mp_nexthop_local;
  
  	/* ifIndex corresponding to mp_nexthop_local. */
  	ifindex_t nh_lla_ifindex;
  
  	/* Extended Communities attribute. */
  	struct ecommunity *ecommunity;
  
  	/* Extended Communities attribute. */
  	struct ecommunity *ipv6_ecommunity;
  
  	/* Large Communities attribute. */
  	struct lcommunity *lcommunity;
  
  	/* Route-Reflector Cluster attribute */
  	struct cluster_list *cluster1;
  
  	/* Unknown transitive attribute. */
  	struct transit *transit;
  
  	struct in_addr mp_nexthop_global_in;
  
  	/* Aggregator Router ID attribute */
  	struct in_addr aggregator_addr;
  
  	/* Route Reflector Originator attribute */
  	struct in_addr originator_id;
  
  	/* Local weight, not actually an attribute */
  	uint32_t weight;
  
  	/* Aggregator ASN */
  	as_t aggregator_as;
  
  	/* MP Nexthop length */
  	uint8_t mp_nexthop_len;
  
  	/* MP Nexthop preference */
  	uint8_t mp_nexthop_prefer_global;
  
  	/* Static MAC for EVPN */
  	uint8_t sticky;
  
  	/* Flag for default gateway extended community in EVPN */
  	uint8_t default_gw;
  
  	/* NA router flag (R-bit) support in EVPN */
  	uint8_t router_flag;
  
  	/* ES info */
  	uint8_t es_flags;
  	/* Path is not "locally-active" on the advertising VTEP. This is
  	 * translated into an ARP-ND ECOM.
  	 */
  #define ATTR_ES_PROXY_ADVERT (1 << 0)
  	/* Destination ES is present locally. This flag is set on local
  	 * paths and sync paths
  	 */
  #define ATTR_ES_IS_LOCAL (1 << 1)
  	/* There are one or more non-best paths from ES peers. Note that
  	 * this flag is only set on the local MAC-IP paths in the VNI
  	 * route table (not set in the global routing table). And only
  	 * non-proxy advertisements from an ES peer can result in this
  	 * flag being set.
  	 */
  #define ATTR_ES_PEER_ACTIVE (1 << 2)
  	/* There are one or more non-best proxy paths from ES peers */
  #define ATTR_ES_PEER_PROXY (1 << 3)
  	/* An ES peer has router bit set - only applicable if
  	 * ATTR_ES_PEER_ACTIVE is set
  	 */
  #define ATTR_ES_PEER_ROUTER (1 << 4)
  
  	/* These two flags are only set on L3 routes installed in a
  	 * VRF as a result of EVPN MAC-IP route
  	 * XXX - while splitting up per-family attrs these need to be
  	 * classified as non-EVPN
  	 */
  #define ATTR_ES_L3_NHG_USE (1 << 5)
  #define ATTR_ES_L3_NHG_ACTIVE (1 << 6)
  #define ATTR_ES_L3_NHG (ATTR_ES_L3_NHG_USE | ATTR_ES_L3_NHG_ACTIVE)
  
  	/* route tag */
  	route_tag_t tag;
  
  	/* Label index */
  	uint32_t label_index;
  
  	/* MPLS label */
  	mpls_label_t label;
  
  	/* SRv6 VPN SID */
  	struct bgp_attr_srv6_vpn *srv6_vpn;
  
  	/* SRv6 L3VPN SID */
  	struct bgp_attr_srv6_l3vpn *srv6_l3vpn;
  
  	uint16_t encap_tunneltype;		     /* grr */
  	struct bgp_attr_encap_subtlv *encap_subtlvs; /* rfc5512 */
  
  #ifdef ENABLE_BGP_VNC
  	struct bgp_attr_encap_subtlv *vnc_subtlvs; /* VNC-specific */
  #endif
  	/* EVPN */
  	struct bgp_route_evpn evpn_overlay;
  
  	/* EVPN MAC Mobility sequence number, if any. */
  	uint32_t mm_seqnum;
  	/* highest MM sequence number rxed in a MAC-IP route from an
  	 * ES peer (this includes both proxy and non-proxy MAC-IP
  	 * advertisements from ES peers).
  	 * This is only applicable to local paths in the VNI routing
  	 * table and derived from other imported/non-best paths.
  	 */
  	uint32_t mm_sync_seqnum;
  
  	/* EVPN local router-mac */
  	struct ethaddr rmac;
  
  	/* Distance as applied by Route map */
  	uint8_t distance;
  
  	/* rmap set table */
  	uint32_t rmap_table_id;
  
  	/* Link bandwidth value, if any. */
  	uint32_t link_bw;
  
  	/* EVPN ES */
  	esi_t esi;
  
  	/* SR-TE Color */
  	uint32_t srte_color;
  
  	/* EVPN DF preference and algorithm for DF election on local ESs */
  	uint16_t df_pref;
  	uint8_t df_alg;
  
  	/* Nexthop type */
  	enum nexthop_types_t nh_type;
  
  	/* If NEXTHOP_TYPE_BLACKHOLE, then blackhole type */
  	enum blackhole_type bh_type;
  };
  
  /* rmap_change_flags definition */
  #define BATTR_RMAP_IPV4_NHOP_CHANGED (1 << 0)
  #define BATTR_RMAP_NEXTHOP_PEER_ADDRESS (1 << 1)
  #define BATTR_REFLECTED (1 << 2)
  #define BATTR_RMAP_NEXTHOP_UNCHANGED (1 << 3)
  #define BATTR_RMAP_IPV6_GLOBAL_NHOP_CHANGED (1 << 4)
  #define BATTR_RMAP_IPV6_LL_NHOP_CHANGED (1 << 5)
  #define BATTR_RMAP_IPV6_PREFER_GLOBAL_CHANGED (1 << 6)
  #define BATTR_RMAP_LINK_BW_SET (1 << 7)
  
  /* Router Reflector related structure. */
  struct cluster_list {
  	unsigned long refcnt;
  	int length;
  	struct in_addr *list;
  };
  
  /* Unknown transit attribute. */
  struct transit {
  	unsigned long refcnt;
  	int length;
  	uint8_t *val;
  };
  
  /* "(void) 0" will generate a compiler error.  this is a safety check to
   * ensure we're not using a value that exceeds the bit size of attr->flag. */
  #define ATTR_FLAG_BIT(X)                                                       \
  	__builtin_choose_expr((X) >= 1 && (X) <= 64, 1ULL << ((X)-1), (void)0)
  
  #define BGP_CLUSTER_LIST_LENGTH(attr)                                          \
  	(((attr)->flag & ATTR_FLAG_BIT(BGP_ATTR_CLUSTER_LIST))                 \
  		 ? bgp_attr_get_cluster((attr))->length                        \
  		 : 0)
  
  typedef enum {
  	BGP_ATTR_PARSE_PROCEED = 0,
  	BGP_ATTR_PARSE_ERROR = -1,
  	BGP_ATTR_PARSE_WITHDRAW = -2,
  
  	/* only used internally, send notify + convert to BGP_ATTR_PARSE_ERROR
  	   */
  	BGP_ATTR_PARSE_ERROR_NOTIFYPLS = -3,
  	BGP_ATTR_PARSE_EOR = -4,
  } bgp_attr_parse_ret_t;
  
  struct bpacket_attr_vec_arr;
  
  /* Prototypes. */
  extern void bgp_attr_init(void);
  extern void bgp_attr_finish(void);
  extern bgp_attr_parse_ret_t bgp_attr_parse(struct peer *, struct attr *,
  					   bgp_size_t, struct bgp_nlri *,
  					   struct bgp_nlri *);
  extern void bgp_attr_undup(struct attr *new, struct attr *old);
  extern struct attr *bgp_attr_intern(struct attr *attr);
  extern void bgp_attr_unintern_sub(struct attr *);
  extern void bgp_attr_unintern(struct attr **);
  extern void bgp_attr_flush(struct attr *);
  extern struct attr *bgp_attr_default_set(struct attr *attr, uint8_t);
  extern struct attr *bgp_attr_aggregate_intern(
  	struct bgp *bgp, uint8_t origin, struct aspath *aspath,
  	struct community *community, struct ecommunity *ecommunity,
  	struct lcommunity *lcommunity, struct bgp_aggregate *aggregate,
  	uint8_t atomic_aggregate, const struct prefix *p);
  extern bgp_size_t bgp_packet_attribute(struct bgp *bgp, struct peer *,
  				       struct stream *, struct attr *,
  				       struct bpacket_attr_vec_arr *vecarr,
  				       struct prefix *, afi_t, safi_t,
  				       struct peer *, struct prefix_rd *,
  				       mpls_label_t *, uint32_t, int, uint32_t);
  extern void bgp_dump_routes_attr(struct stream *s, struct attr *attr,
  				 const struct prefix *p);
  extern bool attrhash_cmp(const void *arg1, const void *arg2);
  extern unsigned int attrhash_key_make(const void *);
  extern void attr_show_all(struct vty *);
  extern unsigned long int attr_count(void);
  extern unsigned long int attr_unknown_count(void);
  
  /* Cluster list prototypes. */
  extern bool cluster_loop_check(struct cluster_list *, struct in_addr);
  
  /* Below exported for unit-test purposes only */
  struct bgp_attr_parser_args {
  	struct peer *peer;
  	bgp_size_t length; /* attribute data length; */
  	bgp_size_t total;  /* total length, inc header */
  	struct attr *attr;
  	uint8_t type;
  	uint8_t flags;
  	uint8_t *startp;
  };
  extern int bgp_mp_reach_parse(struct bgp_attr_parser_args *args,
  			      struct bgp_nlri *);
  extern int bgp_mp_unreach_parse(struct bgp_attr_parser_args *args,
  				struct bgp_nlri *);
  extern bgp_attr_parse_ret_t
  bgp_attr_prefix_sid(struct bgp_attr_parser_args *args);
  
  extern struct bgp_attr_encap_subtlv *
  encap_tlv_dup(struct bgp_attr_encap_subtlv *orig);
  
  extern void bgp_attr_flush_encap(struct attr *attr);
  
  extern void bgp_attr_extcom_tunnel_type(struct attr *attr,
  					 bgp_encap_types *tunnel_type);
  
  /**
   * Set of functions to encode MP_REACH_NLRI and MP_UNREACH_NLRI attributes.
   * Typical call sequence is to call _start(), followed by multiple _prefix(),
   * one for each NLRI that needs to be encoded into the UPDATE message, and
   * finally the _end() function.
   */
  extern size_t bgp_packet_mpattr_start(struct stream *s, struct peer *peer,
  				      afi_t afi, safi_t safi,
  				      struct bpacket_attr_vec_arr *vecarr,
  				      struct attr *attr);
  extern void bgp_packet_mpattr_prefix(struct stream *s, afi_t afi, safi_t safi,
  				     const struct prefix *p,
  				     const struct prefix_rd *prd,
  				     mpls_label_t *label, uint32_t num_labels,
  				     int addpath_encode, uint32_t addpath_tx_id,
  				     struct attr *);
  extern size_t bgp_packet_mpattr_prefix_size(afi_t afi, safi_t safi,
  					    const struct prefix *p);
  extern void bgp_packet_mpattr_end(struct stream *s, size_t sizep);
  
  extern size_t bgp_packet_mpunreach_start(struct stream *s, afi_t afi,
  					 safi_t safi);
  extern void bgp_packet_mpunreach_prefix(
  	struct stream *s, const struct prefix *p, afi_t afi, safi_t safi,
  	const struct prefix_rd *prd, mpls_label_t *label, uint32_t num_labels,
  	int addpath_encode, uint32_t addpath_tx_id, struct attr *attr);
  extern void bgp_packet_mpunreach_end(struct stream *s, size_t attrlen_pnt);
  
  extern bgp_attr_parse_ret_t bgp_attr_nexthop_valid(struct peer *peer,
  						   struct attr *attr);
  
  static inline int bgp_rmap_nhop_changed(uint32_t out_rmap_flags,
  					uint32_t in_rmap_flags)
  {
  	return ((CHECK_FLAG(out_rmap_flags, BATTR_RMAP_NEXTHOP_PEER_ADDRESS)
  		 || CHECK_FLAG(out_rmap_flags, BATTR_RMAP_NEXTHOP_UNCHANGED)
  		 || CHECK_FLAG(out_rmap_flags, BATTR_RMAP_IPV4_NHOP_CHANGED)
  		 || CHECK_FLAG(out_rmap_flags,
  			       BATTR_RMAP_IPV6_GLOBAL_NHOP_CHANGED)
  		 || CHECK_FLAG(out_rmap_flags,
  			       BATTR_RMAP_IPV6_PREFER_GLOBAL_CHANGED)
  		 || CHECK_FLAG(out_rmap_flags, BATTR_RMAP_IPV6_LL_NHOP_CHANGED)
  		 || CHECK_FLAG(in_rmap_flags, BATTR_RMAP_NEXTHOP_UNCHANGED))
  			? 1
  			: 0);
  }
  
  static inline uint32_t mac_mobility_seqnum(struct attr *attr)
  {
  	return (attr) ? attr->mm_seqnum : 0;
  }
  
  static inline enum pta_type bgp_attr_get_pmsi_tnl_type(struct attr *attr)
  {
  	return attr->pmsi_tnl_type;
  }
  
  static inline void bgp_attr_set_pmsi_tnl_type(struct attr *attr,
  					      enum pta_type pmsi_tnl_type)
  {
  	attr->pmsi_tnl_type = pmsi_tnl_type;
  }
  
  static inline struct ecommunity *
  bgp_attr_get_ipv6_ecommunity(const struct attr *attr)
  {
  	return attr->ipv6_ecommunity;
  }
  
  static inline void bgp_attr_set_ipv6_ecommunity(struct attr *attr,
  						struct ecommunity *ipv6_ecomm)
  {
  	attr->ipv6_ecommunity = ipv6_ecomm;
  }
  
  static inline struct transit *bgp_attr_get_transit(const struct attr *attr)
  {
  	return attr->transit;
  }
  
  static inline void bgp_attr_set_transit(struct attr *attr,
  					struct transit *transit)
  {
  	attr->transit = transit;
  }
  
  static inline struct cluster_list *bgp_attr_get_cluster(const struct attr *attr)
  {
  	return attr->cluster1;
  }
  
  static inline void bgp_attr_set_cluster(struct attr *attr,
  					struct cluster_list *cl)
  {
  	attr->cluster1 = cl;
  }
  
  static inline const struct bgp_route_evpn *
  bgp_attr_get_evpn_overlay(const struct attr *attr)
  {
  	return &attr->evpn_overlay;
  }
  
  static inline void bgp_attr_set_evpn_overlay(struct attr *attr,
  					     struct bgp_route_evpn *eo)
  {
  	memcpy(&attr->evpn_overlay, eo, sizeof(struct bgp_route_evpn));
  }
  
  static inline struct bgp_attr_encap_subtlv *
  bgp_attr_get_vnc_subtlvs(const struct attr *attr)
  {
  #ifdef ENABLE_BGP_VNC
  	return attr->vnc_subtlvs;
  #else
  	return NULL;
  #endif
  }
  
  static inline void
  bgp_attr_set_vnc_subtlvs(struct attr *attr,
  			 struct bgp_attr_encap_subtlv *vnc_subtlvs)
  {
  #ifdef ENABLE_BGP_VNC
  	attr->vnc_subtlvs = vnc_subtlvs;
  #endif
  }
  
  #endif /* _QUAGGA_BGP_ATTR_H */
  