/src/frr/bgpd/bgp_nexthop.c

Source
// SPDX-License-Identifier: GPL-2.0-or-later
/* BGP nexthop scan
 * Copyright (C) 2000 Kunihiro Ishiguro
 */

#include <zebra.h>

#include "command.h"
#include "frrevent.h"
#include "prefix.h"
#include "lib/json.h"
#include "zclient.h"
#include "stream.h"
#include "network.h"
#include "log.h"
#include "memory.h"
#include "hash.h"
#include "jhash.h"
#include "nexthop.h"
#include "queue.h"
#include "filter.h"
#include "printfrr.h"

#include "bgpd/bgpd.h"
#include "bgpd/bgp_route.h"
#include "bgpd/bgp_attr.h"
#include "bgpd/bgp_nexthop.h"
#include "bgpd/bgp_nht.h"
#include "bgpd/bgp_debug.h"
#include "bgpd/bgp_damp.h"
#include "bgpd/bgp_fsm.h"
#include "bgpd/bgp_vty.h"
#include "bgpd/bgp_rd.h"
#include "bgpd/bgp_mplsvpn.h"

DEFINE_MTYPE_STATIC(BGPD, MARTIAN_STRING, "BGP Martian Addr Intf String");

int bgp_nexthop_cache_compare(const struct bgp_nexthop_cache *a,
            const struct bgp_nexthop_cache *b)
{
  if (a->srte_color < b->srte_color)
    return -1;
  if (a->srte_color > b->srte_color)
    return 1;

  if (a->ifindex < b->ifindex)
    return -1;
  if (a->ifindex > b->ifindex)
    return 1;

  return prefix_cmp(&a->prefix, &b->prefix);
}

void bnc_nexthop_free(struct bgp_nexthop_cache *bnc)
{
  nexthops_free(bnc->nexthop);
}

struct bgp_nexthop_cache *bnc_new(struct bgp_nexthop_cache_head *tree,
          struct prefix *prefix, uint32_t srte_color,
          ifindex_t ifindex)
{
  struct bgp_nexthop_cache *bnc;

  bnc = XCALLOC(MTYPE_BGP_NEXTHOP_CACHE,
          sizeof(struct bgp_nexthop_cache));
  bnc->prefix = *prefix;
  bnc->ifindex = ifindex;
  bnc->srte_color = srte_color;
  bnc->tree = tree;
  LIST_INIT(&(bnc->paths));
  bgp_nexthop_cache_add(tree, bnc);

  return bnc;
}

bool bnc_existing_for_prefix(struct bgp_nexthop_cache *bnc)
{
  struct bgp_nexthop_cache *bnc_tmp;

  frr_each (bgp_nexthop_cache, bnc->tree, bnc_tmp) {
    if (bnc_tmp == bnc)
      continue;
    if (prefix_cmp(&bnc->prefix, &bnc_tmp->prefix) == 0)
      return true;
  }
  return false;
}

void bnc_free(struct bgp_nexthop_cache *bnc)
{
  bnc_nexthop_free(bnc);
  bgp_nexthop_cache_del(bnc->tree, bnc);
  XFREE(MTYPE_BGP_NEXTHOP_CACHE, bnc);
}

struct bgp_nexthop_cache *bnc_find(struct bgp_nexthop_cache_head *tree,
           struct prefix *prefix, uint32_t srte_color,
           ifindex_t ifindex)
{
  struct bgp_nexthop_cache bnc = {};

  if (!tree)
    return NULL;

  bnc.prefix = *prefix;
  bnc.srte_color = srte_color;
  bnc.ifindex = ifindex;
  return bgp_nexthop_cache_find(tree, &bnc);
}

/* Reset and free all BGP nexthop cache. */
static void bgp_nexthop_cache_reset(struct bgp_nexthop_cache_head *tree)
{
  struct bgp_nexthop_cache *bnc;

  while (bgp_nexthop_cache_count(tree) > 0) {
    bnc = bgp_nexthop_cache_first(tree);

    while (!LIST_EMPTY(&(bnc->paths))) {
      struct bgp_path_info *path = LIST_FIRST(&(bnc->paths));

      bgp_mplsvpn_path_nh_label_unlink(path);

      path_nh_map(path, bnc, false);
    }

    bnc_free(bnc);
  }
}

static void *bgp_tip_hash_alloc(void *p)
{
  const struct in_addr *val = (const struct in_addr *)p;
  struct tip_addr *addr;

  addr = XMALLOC(MTYPE_TIP_ADDR, sizeof(struct tip_addr));
  addr->refcnt = 0;
  addr->addr.s_addr = val->s_addr;

  return addr;
}

static void bgp_tip_hash_free(void *addr)
{
  XFREE(MTYPE_TIP_ADDR, addr);
}

static unsigned int bgp_tip_hash_key_make(const void *p)
{
  const struct tip_addr *addr = p;

  return jhash_1word(addr->addr.s_addr, 0);
}

static bool bgp_tip_hash_cmp(const void *p1, const void *p2)
{
  const struct tip_addr *addr1 = p1;
  const struct tip_addr *addr2 = p2;

  return addr1->addr.s_addr == addr2->addr.s_addr;
}

void bgp_tip_hash_init(struct bgp *bgp)
{
  bgp->tip_hash = hash_create(bgp_tip_hash_key_make, bgp_tip_hash_cmp,
            "BGP TIP hash");
}

void bgp_tip_hash_destroy(struct bgp *bgp)
{
  hash_clean_and_free(&bgp->tip_hash, bgp_tip_hash_free);
}

/* Add/Update Tunnel-IP entry of bgp martian next-hop table.
 *
 * Returns true only if we add a _new_ TIP so the caller knows that an
 * actionable change has occurred. If we find an existing TIP then we
 * only need to update the refcnt, since the collection of known TIPs
 * has not changed.
 */
bool bgp_tip_add(struct bgp *bgp, struct in_addr *tip)
{
  struct tip_addr tmp;
  struct tip_addr *addr;
  bool tip_added = false;

  tmp.addr = *tip;

  addr = hash_lookup(bgp->tip_hash, &tmp);
  if (!addr) {
    addr = hash_get(bgp->tip_hash, &tmp, bgp_tip_hash_alloc);
    tip_added = true;
  }

  addr->refcnt++;

  return tip_added;
}

void bgp_tip_del(struct bgp *bgp, struct in_addr *tip)
{
  struct tip_addr tmp;
  struct tip_addr *addr;

  tmp.addr = *tip;

  addr = hash_lookup(bgp->tip_hash, &tmp);
  /* may have been deleted earlier by bgp_interface_down() */
  if (addr == NULL)
    return;

  addr->refcnt--;

  if (addr->refcnt == 0) {
    hash_release(bgp->tip_hash, addr);
    XFREE(MTYPE_TIP_ADDR, addr);
  }
}

/* BGP own address structure */
struct bgp_addr {
  struct prefix p;
  struct list *ifp_name_list;
};

static void show_address_entry(struct hash_bucket *bucket, void *args)
{
  struct vty *vty = (struct vty *)args;
  struct bgp_addr *addr = (struct bgp_addr *)bucket->data;
  char *name;
  struct listnode *node;
  char str[INET6_ADDRSTRLEN] = {0};

  vty_out(vty, "addr: %s, count: %d : ",
    inet_ntop(addr->p.family, &(addr->p.u.prefix),
        str, INET6_ADDRSTRLEN),
    addr->ifp_name_list->count);

  for (ALL_LIST_ELEMENTS_RO(addr->ifp_name_list, node, name)) {
    vty_out(vty, " %s,", name);
  }

  vty_out(vty, "\n");
}

void bgp_nexthop_show_address_hash(struct vty *vty, struct bgp *bgp)
{
  hash_iterate(bgp->address_hash,
         (void (*)(struct hash_bucket *, void *))show_address_entry,
         vty);
}

static void bgp_address_hash_string_del(void *val)
{
  char *data = val;

  XFREE(MTYPE_MARTIAN_STRING, data);
}

static void *bgp_address_hash_alloc(void *p)
{
  struct bgp_addr *copy_addr = p;
  struct bgp_addr *addr = NULL;

  addr = XMALLOC(MTYPE_BGP_ADDR, sizeof(struct bgp_addr));
  prefix_copy(&addr->p, &copy_addr->p);

  addr->ifp_name_list = list_new();
  addr->ifp_name_list->del = bgp_address_hash_string_del;

  return addr;
}

static void bgp_address_hash_free(void *data)
{
  struct bgp_addr *addr = data;

  list_delete(&addr->ifp_name_list);
  XFREE(MTYPE_BGP_ADDR, addr);
}

static unsigned int bgp_address_hash_key_make(const void *p)
{
  const struct bgp_addr *addr = p;

  return prefix_hash_key(&addr->p);
}

static bool bgp_address_hash_cmp(const void *p1, const void *p2)
{
  const struct bgp_addr *addr1 = p1;
  const struct bgp_addr *addr2 = p2;

  return prefix_same(&addr1->p, &addr2->p);
}

void bgp_address_init(struct bgp *bgp)
{
  bgp->address_hash =
    hash_create(bgp_address_hash_key_make, bgp_address_hash_cmp,
        "BGP Connected Address Hash");
}

void bgp_address_destroy(struct bgp *bgp)
{
  hash_clean_and_free(&bgp->address_hash, bgp_address_hash_free);
}

static void bgp_address_add(struct bgp *bgp, struct connected *ifc,
          struct prefix *p)
{
  struct bgp_addr tmp;
  struct bgp_addr *addr;
  struct listnode *node;
  char *name;

  tmp.p = *p;

  if (tmp.p.family == AF_INET)
    tmp.p.prefixlen = IPV4_MAX_BITLEN;
  else if (tmp.p.family == AF_INET6)
    tmp.p.prefixlen = IPV6_MAX_BITLEN;

  addr = hash_get(bgp->address_hash, &tmp, bgp_address_hash_alloc);

  for (ALL_LIST_ELEMENTS_RO(addr->ifp_name_list, node, name)) {
    if (strcmp(ifc->ifp->name, name) == 0)
      break;
  }
  if (!node) {
    name = XSTRDUP(MTYPE_MARTIAN_STRING, ifc->ifp->name);
    listnode_add(addr->ifp_name_list, name);
  }
}

static void bgp_address_del(struct bgp *bgp, struct connected *ifc,
          struct prefix *p)
{
  struct bgp_addr tmp;
  struct bgp_addr *addr;
  struct listnode *node;
  char *name;

  tmp.p = *p;

  if (tmp.p.family == AF_INET)
    tmp.p.prefixlen = IPV4_MAX_BITLEN;
  else if (tmp.p.family == AF_INET6)
    tmp.p.prefixlen = IPV6_MAX_BITLEN;

  addr = hash_lookup(bgp->address_hash, &tmp);
  /* may have been deleted earlier by bgp_interface_down() */
  if (addr == NULL)
    return;

  for (ALL_LIST_ELEMENTS_RO(addr->ifp_name_list, node, name)) {
    if (strcmp(ifc->ifp->name, name) == 0)
      break;
  }

  if (node) {
    list_delete_node(addr->ifp_name_list, node);
    XFREE(MTYPE_MARTIAN_STRING, name);
  }

  if (addr->ifp_name_list->count == 0) {
    hash_release(bgp->address_hash, addr);
    list_delete(&addr->ifp_name_list);
    XFREE(MTYPE_BGP_ADDR, addr);
  }
}


struct bgp_connected_ref {
  unsigned int refcnt;
};

void bgp_connected_add(struct bgp *bgp, struct connected *ifc)
{
  struct prefix p;
  struct prefix *addr;
  struct bgp_dest *dest;
  struct bgp_connected_ref *bc;
  struct listnode *node, *nnode;
  struct peer *peer;

  addr = ifc->address;

  p = *(CONNECTED_PREFIX(ifc));
  if (addr->family == AF_INET) {
    apply_mask_ipv4((struct prefix_ipv4 *)&p);

    if (prefix_ipv4_any((struct prefix_ipv4 *)&p))
      return;

    bgp_address_add(bgp, ifc, addr);

    dest = bgp_node_get(bgp->connected_table[AFI_IP], &p);
    bc = bgp_dest_get_bgp_connected_ref_info(dest);
    if (bc)
      bc->refcnt++;
    else {
      bc = XCALLOC(MTYPE_BGP_CONN,
             sizeof(struct bgp_connected_ref));
      bc->refcnt = 1;
      bgp_dest_set_bgp_connected_ref_info(dest, bc);
    }

    for (ALL_LIST_ELEMENTS(bgp->peer, node, nnode, peer)) {
      if (peer->conf_if
          && (strcmp(peer->conf_if, ifc->ifp->name) == 0)
          && !peer_established(peer)
          && !CHECK_FLAG(peer->flags,
             PEER_FLAG_IFPEER_V6ONLY)) {
        if (peer_active(peer))
          BGP_EVENT_ADD(peer, BGP_Stop);
        BGP_EVENT_ADD(peer, BGP_Start);
      }
    }
  } else if (addr->family == AF_INET6) {
    apply_mask_ipv6((struct prefix_ipv6 *)&p);

    if (IN6_IS_ADDR_UNSPECIFIED(&p.u.prefix6))
      return;

    if (IN6_IS_ADDR_LINKLOCAL(&p.u.prefix6))
      return;

    bgp_address_add(bgp, ifc, addr);

    dest = bgp_node_get(bgp->connected_table[AFI_IP6], &p);

    bc = bgp_dest_get_bgp_connected_ref_info(dest);
    if (bc)
      bc->refcnt++;
    else {
      bc = XCALLOC(MTYPE_BGP_CONN,
             sizeof(struct bgp_connected_ref));
      bc->refcnt = 1;
      bgp_dest_set_bgp_connected_ref_info(dest, bc);
    }
  }
}

void bgp_connected_delete(struct bgp *bgp, struct connected *ifc)
{
  struct prefix p;
  struct prefix *addr;
  struct bgp_dest *dest = NULL;
  struct bgp_connected_ref *bc;

  addr = ifc->address;

  p = *(CONNECTED_PREFIX(ifc));
  apply_mask(&p);
  if (addr->family == AF_INET) {
    if (prefix_ipv4_any((struct prefix_ipv4 *)&p))
      return;

    bgp_address_del(bgp, ifc, addr);

    dest = bgp_node_lookup(bgp->connected_table[AFI_IP], &p);
  } else if (addr->family == AF_INET6) {
    if (IN6_IS_ADDR_UNSPECIFIED(&p.u.prefix6))
      return;

    if (IN6_IS_ADDR_LINKLOCAL(&p.u.prefix6))
      return;

    bgp_address_del(bgp, ifc, addr);

    dest = bgp_node_lookup(bgp->connected_table[AFI_IP6], &p);
  }

  if (!dest)
    return;

  bc = bgp_dest_get_bgp_connected_ref_info(dest);
  bc->refcnt--;
  if (bc->refcnt == 0) {
    XFREE(MTYPE_BGP_CONN, bc);
    bgp_dest_set_bgp_connected_ref_info(dest, NULL);
  }
  bgp_dest_unlock_node(dest);
  bgp_dest_unlock_node(dest);
}

static void bgp_connected_cleanup(struct route_table *table,
          struct route_node *rn)
{
  struct bgp_connected_ref *bc;
  struct bgp_dest *bn = bgp_dest_from_rnode(rn);

  bc = bgp_dest_get_bgp_connected_ref_info(bn);
  if (!bc)
    return;

  XFREE(MTYPE_BGP_CONN, bc);
  bgp_dest_set_bgp_connected_ref_info(bn, NULL);
}

bool bgp_nexthop_self(struct bgp *bgp, afi_t afi, uint8_t type,
          uint8_t sub_type, struct attr *attr,
          struct bgp_dest *dest)
{
  uint8_t new_afi = afi == AFI_IP ? AF_INET : AF_INET6;
  struct bgp_addr tmp_addr = {{0}}, *addr = NULL;
  struct tip_addr tmp_tip, *tip = NULL;
  const struct prefix *p = bgp_dest_get_prefix(dest);
  bool is_bgp_static_route =
    ((type == ZEBRA_ROUTE_BGP) && (sub_type == BGP_ROUTE_STATIC))
      ? true
      : false;

  if (!is_bgp_static_route)
    new_afi = BGP_ATTR_NEXTHOP_AFI_IP6(attr) ? AF_INET6 : AF_INET;

  tmp_addr.p.family = new_afi;
  switch (new_afi) {
  case AF_INET:
    if (is_bgp_static_route) {
      tmp_addr.p.u.prefix4 = p->u.prefix4;
      tmp_addr.p.prefixlen = p->prefixlen;
    } else {
      /* Here we need to find out which nexthop to be used*/
      if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP)) {
        tmp_addr.p.u.prefix4 = attr->nexthop;
        tmp_addr.p.prefixlen = IPV4_MAX_BITLEN;
      } else if ((attr->mp_nexthop_len)
           && ((attr->mp_nexthop_len
          == BGP_ATTR_NHLEN_IPV4)
               || (attr->mp_nexthop_len
             == BGP_ATTR_NHLEN_VPNV4))) {
        tmp_addr.p.u.prefix4 =
          attr->mp_nexthop_global_in;
        tmp_addr.p.prefixlen = IPV4_MAX_BITLEN;
      } else
        return false;
    }
    break;
  case AF_INET6:
    if (is_bgp_static_route) {
      tmp_addr.p.u.prefix6 = p->u.prefix6;
      tmp_addr.p.prefixlen = p->prefixlen;
    } else {
      tmp_addr.p.u.prefix6 = attr->mp_nexthop_global;
      tmp_addr.p.prefixlen = IPV6_MAX_BITLEN;
    }
    break;
  default:
    break;
  }

  addr = hash_lookup(bgp->address_hash, &tmp_addr);
  if (addr)
    return true;

  if (new_afi == AF_INET && hashcount(bgp->tip_hash)) {
    memset(&tmp_tip, 0, sizeof(tmp_tip));
    tmp_tip.addr = attr->nexthop;

    if (attr->flag & ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP)) {
      tmp_tip.addr = attr->nexthop;
    } else if ((attr->mp_nexthop_len) &&
         ((attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV4)
          || (attr->mp_nexthop_len == BGP_ATTR_NHLEN_VPNV4))) {
      tmp_tip.addr = attr->mp_nexthop_global_in;
    }

    tip = hash_lookup(bgp->tip_hash, &tmp_tip);
    if (tip)
      return true;
  }

  return false;
}

bool bgp_multiaccess_check_v4(struct in_addr nexthop, struct peer *peer)
{
  struct bgp_dest *dest1;
  struct bgp_dest *dest2;
  struct prefix p;
  int ret;

  p.family = AF_INET;
  p.prefixlen = IPV4_MAX_BITLEN;
  p.u.prefix4 = nexthop;

  dest1 = bgp_node_match(peer->bgp->connected_table[AFI_IP], &p);
  if (!dest1)
    return false;

  p.family = AF_INET;
  p.prefixlen = IPV4_MAX_BITLEN;
  p.u.prefix4 = peer->su.sin.sin_addr;

  dest2 = bgp_node_match(peer->bgp->connected_table[AFI_IP], &p);
  if (!dest2) {
    bgp_dest_unlock_node(dest1);
    return false;
  }

  ret = (dest1 == dest2);

  bgp_dest_unlock_node(dest1);
  bgp_dest_unlock_node(dest2);

  return ret;
}

bool bgp_multiaccess_check_v6(struct in6_addr nexthop, struct peer *peer)
{
  struct bgp_dest *dest1;
  struct bgp_dest *dest2;
  struct prefix p;
  int ret;

  p.family = AF_INET6;
  p.prefixlen = IPV6_MAX_BITLEN;
  p.u.prefix6 = nexthop;

  dest1 = bgp_node_match(peer->bgp->connected_table[AFI_IP6], &p);
  if (!dest1)
    return false;

  p.family = AF_INET6;
  p.prefixlen = IPV6_MAX_BITLEN;
  p.u.prefix6 = peer->su.sin6.sin6_addr;

  dest2 = bgp_node_match(peer->bgp->connected_table[AFI_IP6], &p);
  if (!dest2) {
    bgp_dest_unlock_node(dest1);
    return false;
  }

  ret = (dest1 == dest2);

  bgp_dest_unlock_node(dest1);
  bgp_dest_unlock_node(dest2);

  return ret;
}

bool bgp_subgrp_multiaccess_check_v6(struct in6_addr nexthop,
             struct update_subgroup *subgrp,
             struct peer *exclude)
{
  struct bgp_dest *dest1 = NULL, *dest2 = NULL;
  struct peer_af *paf = NULL;
  struct prefix p = {0}, np = {0};
  struct bgp *bgp = NULL;

  np.family = AF_INET6;
  np.prefixlen = IPV6_MAX_BITLEN;
  np.u.prefix6 = nexthop;

  p.family = AF_INET;
  p.prefixlen = IPV6_MAX_BITLEN;

  bgp = SUBGRP_INST(subgrp);
  dest1 = bgp_node_match(bgp->connected_table[AFI_IP6], &np);
  if (!dest1)
    return false;

  SUBGRP_FOREACH_PEER (subgrp, paf) {
    /* Skip peer we're told to exclude - e.g., source of route. */
    if (paf->peer == exclude)
      continue;

    p.u.prefix6 = paf->peer->su.sin6.sin6_addr;
    dest2 = bgp_node_match(bgp->connected_table[AFI_IP6], &p);
    if (dest1 == dest2) {
      bgp_dest_unlock_node(dest1);
      bgp_dest_unlock_node(dest2);
      return true;
    }

    if (dest2)
      bgp_dest_unlock_node(dest2);
  }

  bgp_dest_unlock_node(dest1);
  return false;
}

bool bgp_subgrp_multiaccess_check_v4(struct in_addr nexthop,
             struct update_subgroup *subgrp,
             struct peer *exclude)
{
  struct bgp_dest *dest1, *dest2;
  struct peer_af *paf;
  struct prefix p, np;
  struct bgp *bgp;

  np.family = AF_INET;
  np.prefixlen = IPV4_MAX_BITLEN;
  np.u.prefix4 = nexthop;

  p.family = AF_INET;
  p.prefixlen = IPV4_MAX_BITLEN;

  bgp = SUBGRP_INST(subgrp);
  dest1 = bgp_node_match(bgp->connected_table[AFI_IP], &np);
  if (!dest1)
    return false;

  SUBGRP_FOREACH_PEER (subgrp, paf) {
    /* Skip peer we're told to exclude - e.g., source of route. */
    if (paf->peer == exclude)
      continue;

    p.u.prefix4 = paf->peer->su.sin.sin_addr;

    dest2 = bgp_node_match(bgp->connected_table[AFI_IP], &p);
    if (dest1 == dest2) {
      bgp_dest_unlock_node(dest1);
      bgp_dest_unlock_node(dest2);
      return true;
    }

    if (dest2)
      bgp_dest_unlock_node(dest2);
  }

  bgp_dest_unlock_node(dest1);
  return false;
}

static void bgp_show_bgp_path_info_flags(uint32_t flags, json_object *json)
{
  json_object *json_flags = NULL;

  if (!json)
    return;

  json_flags = json_object_new_object();
  json_object_boolean_add(json_flags, "igpChanged",
        CHECK_FLAG(flags, BGP_PATH_IGP_CHANGED));
  json_object_boolean_add(json_flags, "damped",
        CHECK_FLAG(flags, BGP_PATH_DAMPED));
  json_object_boolean_add(json_flags, "history",
        CHECK_FLAG(flags, BGP_PATH_HISTORY));
  json_object_boolean_add(json_flags, "bestpath",
        CHECK_FLAG(flags, BGP_PATH_SELECTED));
  json_object_boolean_add(json_flags, "valid",
        CHECK_FLAG(flags, BGP_PATH_VALID));
  json_object_boolean_add(json_flags, "attrChanged",
        CHECK_FLAG(flags, BGP_PATH_ATTR_CHANGED));
  json_object_boolean_add(json_flags, "deterministicMedCheck",
        CHECK_FLAG(flags, BGP_PATH_DMED_CHECK));
  json_object_boolean_add(json_flags, "deterministicMedSelected",
        CHECK_FLAG(flags, BGP_PATH_DMED_SELECTED));
  json_object_boolean_add(json_flags, "stale",
        CHECK_FLAG(flags, BGP_PATH_STALE));
  json_object_boolean_add(json_flags, "removed",
        CHECK_FLAG(flags, BGP_PATH_REMOVED));
  json_object_boolean_add(json_flags, "counted",
        CHECK_FLAG(flags, BGP_PATH_COUNTED));
  json_object_boolean_add(json_flags, "multipath",
        CHECK_FLAG(flags, BGP_PATH_MULTIPATH));
  json_object_boolean_add(json_flags, "multipathChanged",
        CHECK_FLAG(flags, BGP_PATH_MULTIPATH_CHG));
  json_object_boolean_add(json_flags, "ribAttributeChanged",
        CHECK_FLAG(flags, BGP_PATH_RIB_ATTR_CHG));
  json_object_boolean_add(json_flags, "nexthopSelf",
        CHECK_FLAG(flags, BGP_PATH_ANNC_NH_SELF));
  json_object_boolean_add(json_flags, "linkBandwidthChanged",
        CHECK_FLAG(flags, BGP_PATH_LINK_BW_CHG));
  json_object_boolean_add(json_flags, "acceptOwn",
        CHECK_FLAG(flags, BGP_PATH_ACCEPT_OWN));
  json_object_object_add(json, "flags", json_flags);
}

static void bgp_show_nexthop_paths(struct vty *vty, struct bgp *bgp,
           struct bgp_nexthop_cache *bnc,
           json_object *json)
{
  struct bgp_dest *dest;
  struct bgp_path_info *path;
  afi_t afi;
  safi_t safi;
  struct bgp_table *table;
  struct bgp *bgp_path;
  json_object *paths = NULL;
  json_object *json_path = NULL;

  if (json)
    paths = json_object_new_array();
  else
    vty_out(vty, "  Paths:\n");
  LIST_FOREACH (path, &(bnc->paths), nh_thread) {
    dest = path->net;
    assert(dest && bgp_dest_table(dest));
    afi = family2afi(bgp_dest_get_prefix(dest)->family);
    table = bgp_dest_table(dest);
    safi = table->safi;
    bgp_path = table->bgp;


    if (json) {
      json_path = json_object_new_object();
      json_object_string_add(json_path, "afi", afi2str(afi));
      json_object_string_add(json_path, "safi",
                 safi2str(safi));
      json_object_string_addf(json_path, "prefix", "%pBD",
            dest);
      if (dest->pdest)
        json_object_string_addf(
          json_path, "rd",
          BGP_RD_AS_FORMAT(bgp->asnotation),
          (struct prefix_rd *)bgp_dest_get_prefix(
            dest->pdest));
      json_object_string_add(
        json_path, "vrf",
        vrf_id_to_name(bgp_path->vrf_id));
      bgp_show_bgp_path_info_flags(path->flags, json_path);
      json_object_array_add(paths, json_path);
      continue;
    }
    if (dest->pdest) {
      vty_out(vty, "    %d/%d %pBD RD ", afi, safi, dest);
      vty_out(vty, BGP_RD_AS_FORMAT(bgp->asnotation),
        (struct prefix_rd *)bgp_dest_get_prefix(
          dest->pdest));
      vty_out(vty, " %s flags 0x%x\n", bgp_path->name_pretty,
        path->flags);
    } else
      vty_out(vty, "    %d/%d %pBD %s flags 0x%x\n",
        afi, safi, dest, bgp_path->name_pretty, path->flags);
  }
  if (json)
    json_object_object_add(json, "paths", paths);
}

static void bgp_show_nexthops_detail(struct vty *vty, struct bgp *bgp,
             struct bgp_nexthop_cache *bnc,
             json_object *json)
{
  struct nexthop *nexthop;
  json_object *json_gates = NULL;
  json_object *json_gate = NULL;

  if (json)
    json_gates = json_object_new_array();
  for (nexthop = bnc->nexthop; nexthop; nexthop = nexthop->next) {
    if (json) {
      json_gate = json_object_new_object();
      switch (nexthop->type) {
      case NEXTHOP_TYPE_IPV6:
        json_object_string_addf(json_gate, "ip", "%pI6",
              &nexthop->gate.ipv6);
        break;
      case NEXTHOP_TYPE_IPV6_IFINDEX:
        json_object_string_addf(json_gate, "ip", "%pI6",
              &nexthop->gate.ipv6);
        json_object_string_add(
          json_gate, "interfaceName",
          ifindex2ifname(
            bnc->ifindex ? bnc->ifindex
                   : nexthop->ifindex,
            bgp->vrf_id));
        break;
      case NEXTHOP_TYPE_IPV4:
        json_object_string_addf(json_gate, "ip", "%pI4",
              &nexthop->gate.ipv4);
        break;
      case NEXTHOP_TYPE_IFINDEX:
        json_object_string_add(
          json_gate, "interfaceName",
          ifindex2ifname(
            bnc->ifindex ? bnc->ifindex
                   : nexthop->ifindex,
            bgp->vrf_id));
        break;
      case NEXTHOP_TYPE_IPV4_IFINDEX:
        json_object_string_addf(json_gate, "ip", "%pI4",
              &nexthop->gate.ipv4);
        json_object_string_add(
          json_gate, "interfaceName",
          ifindex2ifname(
            bnc->ifindex ? bnc->ifindex
                   : nexthop->ifindex,
            bgp->vrf_id));
        break;
      case NEXTHOP_TYPE_BLACKHOLE:
        json_object_boolean_true_add(json_gate,
                   "unreachable");
        switch (nexthop->bh_type) {
        case BLACKHOLE_REJECT:
          json_object_boolean_true_add(json_gate,
                     "reject");
          break;
        case BLACKHOLE_ADMINPROHIB:
          json_object_boolean_true_add(
            json_gate, "adminProhibited");
          break;
        case BLACKHOLE_NULL:
          json_object_boolean_true_add(
            json_gate, "blackhole");
          break;
        case BLACKHOLE_UNSPEC:
          break;
        }
        break;
      default:
        break;
      }
      json_object_array_add(json_gates, json_gate);
      continue;
    }
    switch (nexthop->type) {
    case NEXTHOP_TYPE_IPV6:
    case NEXTHOP_TYPE_IPV6_IFINDEX:
      vty_out(vty, "  gate %pI6", &nexthop->gate.ipv6);
      if (nexthop->type == NEXTHOP_TYPE_IPV6_IFINDEX &&
          bnc->ifindex)
        vty_out(vty, ", if %s\n",
          ifindex2ifname(bnc->ifindex,
                   bgp->vrf_id));
      else if (nexthop->ifindex)
        vty_out(vty, ", if %s\n",
          ifindex2ifname(nexthop->ifindex,
                   bgp->vrf_id));
      else
        vty_out(vty, "\n");
      break;
    case NEXTHOP_TYPE_IPV4:
    case NEXTHOP_TYPE_IPV4_IFINDEX:
      vty_out(vty, "  gate %pI4", &nexthop->gate.ipv4);
      if (nexthop->type == NEXTHOP_TYPE_IPV4_IFINDEX &&
          bnc->ifindex)
        vty_out(vty, ", if %s\n",
          ifindex2ifname(bnc->ifindex,
                   bgp->vrf_id));
      else if (nexthop->ifindex)
        vty_out(vty, ", if %s\n",
          ifindex2ifname(nexthop->ifindex,
                   bgp->vrf_id));
      else
        vty_out(vty, "\n");
      break;
    case NEXTHOP_TYPE_IFINDEX:
      vty_out(vty, "  if %s\n",
        ifindex2ifname(bnc->ifindex ? bnc->ifindex
                  : nexthop->ifindex,
                 bgp->vrf_id));
      break;
    case NEXTHOP_TYPE_BLACKHOLE:
      vty_out(vty, "  blackhole\n");
      break;
    default:
      vty_out(vty, "  invalid nexthop type %u\n",
        nexthop->type);
    }
  }
  if (json)
    json_object_object_add(json, "nexthops", json_gates);
}

static void bgp_show_nexthop(struct vty *vty, struct bgp *bgp,
           struct bgp_nexthop_cache *bnc, bool specific,
           json_object *json)
{
  char buf[PREFIX2STR_BUFFER];
  time_t tbuf;
  struct peer *peer;
  json_object *json_last_update = NULL;
  json_object *json_nexthop = NULL;

  peer = (struct peer *)bnc->nht_info;

  if (json)
    json_nexthop = json_object_new_object();
  if (bnc->srte_color) {
    if (json)
      json_object_int_add(json_nexthop, "srteColor",
              bnc->srte_color);
    else
      vty_out(vty, " SR-TE color %u -", bnc->srte_color);
  }
  inet_ntop(bnc->prefix.family, &bnc->prefix.u.prefix, buf, sizeof(buf));
  if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID)) {
    if (json) {
      json_object_boolean_true_add(json_nexthop, "valid");
      json_object_boolean_true_add(json_nexthop, "complete");
      json_object_int_add(json_nexthop, "igpMetric",
              bnc->metric);
      json_object_int_add(json_nexthop, "pathCount",
              bnc->path_count);
      if (peer)
        json_object_string_add(json_nexthop, "peer",
                   peer->host);
      if (bnc->is_evpn_gwip_nexthop)
        json_object_boolean_true_add(json_nexthop,
                   "isEvpnGatewayIp");
    } else {
      vty_out(vty, " %s valid [IGP metric %d], #paths %d",
        buf, bnc->metric, bnc->path_count);
      if (peer)
        vty_out(vty, ", peer %s", peer->host);
      if (bnc->is_evpn_gwip_nexthop)
        vty_out(vty, " EVPN Gateway IP");
      vty_out(vty, "\n");
    }
    bgp_show_nexthops_detail(vty, bgp, bnc, json_nexthop);
  } else if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_EVPN_INCOMPLETE)) {
    if (json) {
      json_object_boolean_true_add(json_nexthop, "valid");
      json_object_boolean_false_add(json_nexthop, "complete");
      json_object_int_add(json_nexthop, "igpMetric",
              bnc->metric);
      json_object_int_add(json_nexthop, "pathCount",
              bnc->path_count);
      if (bnc->is_evpn_gwip_nexthop)
        json_object_boolean_true_add(json_nexthop,
                   "isEvpnGatewayIp");
    } else {
      vty_out(vty,
        " %s overlay index unresolved [IGP metric %d], #paths %d",
        buf, bnc->metric, bnc->path_count);
      if (bnc->is_evpn_gwip_nexthop)
        vty_out(vty, " EVPN Gateway IP");
      vty_out(vty, "\n");
    }
    bgp_show_nexthops_detail(vty, bgp, bnc, json_nexthop);
  } else {
    if (json) {
      json_object_boolean_false_add(json_nexthop, "valid");
      json_object_boolean_false_add(json_nexthop, "complete");
      json_object_int_add(json_nexthop, "pathCount",
              bnc->path_count);
      if (peer)
        json_object_string_add(json_nexthop, "peer",
                   peer->host);
      if (bnc->is_evpn_gwip_nexthop)
        json_object_boolean_true_add(json_nexthop,
                   "isEvpnGatewayIp");
      if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED))
        json_object_boolean_false_add(json_nexthop,
                    "isConnected");
      if (!CHECK_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED))
        json_object_boolean_false_add(json_nexthop,
                    "isRegistered");
    } else {
      vty_out(vty, " %s invalid, #paths %d", buf,
        bnc->path_count);
      if (peer)
        vty_out(vty, ", peer %s", peer->host);
      if (bnc->is_evpn_gwip_nexthop)
        vty_out(vty, " EVPN Gateway IP");
      vty_out(vty, "\n");
      if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED))
        vty_out(vty, "  Must be Connected\n");
      if (!CHECK_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED))
        vty_out(vty, "  Is not Registered\n");
    }
  }
  tbuf = time(NULL) - (monotime(NULL) - bnc->last_update);
  if (json) {
    if (!specific) {
      json_last_update = json_object_new_object();
      json_object_int_add(json_last_update, "epoch", tbuf);
      json_object_string_add(json_last_update, "string",
                 ctime(&tbuf));
      json_object_object_add(json_nexthop, "lastUpdate",
                 json_last_update);
    } else {
      json_object_int_add(json_nexthop, "lastUpdate", tbuf);
    }
  } else {
    vty_out(vty, "  Last update: %s", ctime(&tbuf));
  }

  /* show paths dependent on nexthop, if needed. */
  if (specific)
    bgp_show_nexthop_paths(vty, bgp, bnc, json_nexthop);
  if (json)
    json_object_object_add(json, buf, json_nexthop);
}

static void bgp_show_nexthops(struct vty *vty, struct bgp *bgp,
            bool import_table, json_object *json, afi_t afi,
            bool detail)
{
  struct bgp_nexthop_cache *bnc;
  struct bgp_nexthop_cache_head(*tree)[AFI_MAX];
  json_object *json_afi = NULL;
  bool found = false;

  if (!json) {
    if (import_table)
      vty_out(vty, "Current BGP import check cache:\n");
    else
      vty_out(vty, "Current BGP nexthop cache:\n");
  }
  if (import_table)
    tree = &bgp->import_check_table;
  else
    tree = &bgp->nexthop_cache_table;

  if (afi == AFI_IP || afi == AFI_IP6) {
    if (json)
      json_afi = json_object_new_object();
    frr_each (bgp_nexthop_cache, &(*tree)[afi], bnc) {
      bgp_show_nexthop(vty, bgp, bnc, detail, json_afi);
      found = true;
    }
    if (found && json)
      json_object_object_add(
        json, (afi == AFI_IP) ? "ipv4" : "ipv6",
        json_afi);
    return;
  }

  for (afi = AFI_IP; afi < AFI_MAX; afi++) {
    if (json && (afi == AFI_IP || afi == AFI_IP6))
      json_afi = json_object_new_object();
    frr_each (bgp_nexthop_cache, &(*tree)[afi], bnc)
      bgp_show_nexthop(vty, bgp, bnc, detail, json_afi);
    if (json && (afi == AFI_IP || afi == AFI_IP6))
      json_object_object_add(
        json, (afi == AFI_IP) ? "ipv4" : "ipv6",
        json_afi);
  }
}

static int show_ip_bgp_nexthop_table(struct vty *vty, const char *name,
             const char *nhopip_str, bool import_table,
             json_object *json, afi_t afi, bool detail)
{
  struct bgp *bgp;

  if (name && !strmatch(name, VRF_DEFAULT_NAME))
    bgp = bgp_lookup_by_name(name);
  else
    bgp = bgp_get_default();
  if (!bgp) {
    if (!json)
      vty_out(vty, "%% No such BGP instance exist\n");
    return CMD_WARNING;
  }

  if (nhopip_str) {
    struct prefix nhop;
    struct bgp_nexthop_cache_head (*tree)[AFI_MAX];
    struct bgp_nexthop_cache *bnc;
    bool found = false;
    json_object *json_afi = NULL;

    if (!str2prefix(nhopip_str, &nhop)) {
      if (!json)
        vty_out(vty, "nexthop address is malformed\n");
      return CMD_WARNING;
    }
    tree = import_table ? &bgp->import_check_table
            : &bgp->nexthop_cache_table;
    if (json)
      json_afi = json_object_new_object();
    frr_each (bgp_nexthop_cache, &(*tree)[family2afi(nhop.family)],
        bnc) {
      if (prefix_cmp(&bnc->prefix, &nhop))
        continue;
      bgp_show_nexthop(vty, bgp, bnc, true, json_afi);
      found = true;
    }
    if (json)
      json_object_object_add(
        json,
        (family2afi(nhop.family) == AFI_IP) ? "ipv4"
                    : "ipv6",
        json_afi);
    if (!found && !json)
      vty_out(vty, "nexthop %s does not have entry\n",
        nhopip_str);
  } else
    bgp_show_nexthops(vty, bgp, import_table, json, afi, detail);

  return CMD_SUCCESS;
}

static void bgp_show_all_instances_nexthops_vty(struct vty *vty,
            json_object *json, afi_t afi,
            bool detail)
{
  struct listnode *node, *nnode;
  struct bgp *bgp;
  const char *inst_name;
  json_object *json_instance = NULL;

  for (ALL_LIST_ELEMENTS(bm->bgp, node, nnode, bgp)) {
    inst_name = (bgp->inst_type == BGP_INSTANCE_TYPE_DEFAULT)
            ? VRF_DEFAULT_NAME
            : bgp->name;
    if (json)
      json_instance = json_object_new_object();
    else
      vty_out(vty, "\nInstance %s:\n", inst_name);

    bgp_show_nexthops(vty, bgp, false, json_instance, afi, detail);

    if (json)
      json_object_object_add(json, inst_name, json_instance);
  }
}

#include "bgpd/bgp_nexthop_clippy.c"

DEFPY (show_ip_bgp_nexthop,
       show_ip_bgp_nexthop_cmd,
       "show [ip] bgp [<view|vrf> VIEWVRFNAME$vrf] nexthop [<A.B.C.D|X:X::X:X>$nhop] [<ipv4$afi [A.B.C.D$nhop]|ipv6$afi [X:X::X:X$nhop]>] [detail$detail] [json$uj]",
       SHOW_STR
       IP_STR
       BGP_STR
       BGP_INSTANCE_HELP_STR
       "BGP nexthop table\n"
       "IPv4 nexthop address\n"
       "IPv6 nexthop address\n"
       "BGP nexthop IPv4 table\n"
       "IPv4 nexthop address\n"
       "BGP nexthop IPv6 table\n"
       "IPv6 nexthop address\n"
       "Show detailed information\n"
       JSON_STR)
{
  int rc = 0;
  json_object *json = NULL;
  afi_t afiz = AFI_UNSPEC;

  if (uj)
    json = json_object_new_object();

  if (afi)
    afiz = bgp_vty_afi_from_str(afi);

  rc = show_ip_bgp_nexthop_table(vty, vrf, nhop_str, false, json, afiz,
               detail);

  if (uj)
    vty_json(vty, json);

  return rc;
}

DEFPY (show_ip_bgp_import_check,
       show_ip_bgp_import_check_cmd,
       "show [ip] bgp [<view|vrf> VIEWVRFNAME$vrf] import-check-table [detail$detail] [json$uj]",
       SHOW_STR
       IP_STR
       BGP_STR
       BGP_INSTANCE_HELP_STR
       "BGP import check table\n"
       "Show detailed information\n"
       JSON_STR)
{
  int rc = 0;
  json_object *json = NULL;

  if (uj)
    json = json_object_new_object();

  rc = show_ip_bgp_nexthop_table(vty, vrf, NULL, true, json, AFI_UNSPEC,
               detail);

  if (uj)
    vty_json(vty, json);

  return rc;
}

DEFPY (show_ip_bgp_instance_all_nexthop,
       show_ip_bgp_instance_all_nexthop_cmd,
       "show [ip] bgp <view|vrf> all nexthop [<ipv4|ipv6>$afi] [detail$detail] [json$uj]",
       SHOW_STR
       IP_STR
       BGP_STR
       BGP_INSTANCE_ALL_HELP_STR
       "BGP nexthop table\n"
       "BGP IPv4 nexthop table\n"
       "BGP IPv6 nexthop table\n"
       "Show detailed information\n"
       JSON_STR)
{
  json_object *json = NULL;
  afi_t afiz = AFI_UNSPEC;

  if (uj)
    json = json_object_new_object();

  if (afi)
    afiz = bgp_vty_afi_from_str(afi);

  bgp_show_all_instances_nexthops_vty(vty, json, afiz, detail);

  if (uj)
    vty_json(vty, json);

  return CMD_SUCCESS;
}

void bgp_scan_init(struct bgp *bgp)
{
  afi_t afi;

  for (afi = AFI_IP; afi < AFI_MAX; afi++) {
    bgp_nexthop_cache_init(&bgp->nexthop_cache_table[afi]);
    bgp_nexthop_cache_init(&bgp->import_check_table[afi]);
    bgp->connected_table[afi] = bgp_table_init(bgp, afi,
      SAFI_UNICAST);
  }
}

void bgp_scan_vty_init(void)
{
  install_element(VIEW_NODE, &show_ip_bgp_nexthop_cmd);
  install_element(VIEW_NODE, &show_ip_bgp_import_check_cmd);
  install_element(VIEW_NODE, &show_ip_bgp_instance_all_nexthop_cmd);
}

void bgp_scan_finish(struct bgp *bgp)
{
  afi_t afi;

  for (afi = AFI_IP; afi < AFI_MAX; afi++) {
    /* Only the current one needs to be reset. */
    bgp_nexthop_cache_reset(&bgp->nexthop_cache_table[afi]);
    bgp_nexthop_cache_reset(&bgp->import_check_table[afi]);

    bgp->connected_table[afi]->route_table->cleanup =
      bgp_connected_cleanup;
    bgp_table_unlock(bgp->connected_table[afi]);
    bgp->connected_table[afi] = NULL;
  }
}

char *bgp_nexthop_dump_bnc_flags(struct bgp_nexthop_cache *bnc, char *buf,
         size_t len)
{
  if (bnc->flags == 0) {
    snprintfrr(buf, len, "None ");
    return buf;
  }

  snprintfrr(buf, len, "%s%s%s%s%s%s%s",
       CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID) ? "Valid " : "",
       CHECK_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED) ? "Reg " : "",
       CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED) ? "Conn " : "",
       CHECK_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED) ? "Notify "
                     : "",
       CHECK_FLAG(bnc->flags, BGP_STATIC_ROUTE) ? "Static " : "",
       CHECK_FLAG(bnc->flags, BGP_STATIC_ROUTE_EXACT_MATCH)
         ? "Static Exact "
         : "",
       CHECK_FLAG(bnc->flags, BGP_NEXTHOP_LABELED_VALID)
         ? "Label Valid "
         : "");

  return buf;
}

char *bgp_nexthop_dump_bnc_change_flags(struct bgp_nexthop_cache *bnc,
          char *buf, size_t len)
{
  if (bnc->flags == 0) {
    snprintfrr(buf, len, "None ");
    return buf;
  }

  snprintfrr(buf, len, "%s%s%s",
       CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_CHANGED)
         ? "Changed "
         : "",
       CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_METRIC_CHANGED)
         ? "Metric "
         : "",
       CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_CONNECTED_CHANGED)
         ? "Connected "
         : "");

  return buf;
}

Coverage Report

Created: 2026-01-01 06:18