Merge pull request #531 from qlyoung/fix-stack-ref

[mirror_frr.git] / lib / nexthop.c

/* A generic nexthop structure
 * Copyright (C) 2013 Cumulus Networks, Inc.
 *
 * This file is part of Quagga.
 *
 * Quagga 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.
 *
 * Quagga 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 Quagga; see the file COPYING.  If not, write to the Free
 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */
#include <zebra.h>

#include "prefix.h"
#include "table.h"
#include "memory.h"
#include "command.h"
#include "if.h"
#include "log.h"
#include "sockunion.h"
#include "linklist.h"
#include "thread.h"
#include "prefix.h"
#include "nexthop.h"
#include "mpls.h"

DEFINE_MTYPE_STATIC(LIB, NEXTHOP,	"Nexthop")
DEFINE_MTYPE_STATIC(LIB, NH_LABEL,	"Nexthop label")

/* check if nexthops are same, non-recursive */
int
nexthop_same_no_recurse (struct nexthop *next1, struct nexthop *next2)
{
  if (next1->type != next2->type)
    return 0;

  switch (next1->type)
    {
    case NEXTHOP_TYPE_IPV4:
    case NEXTHOP_TYPE_IPV4_IFINDEX:
      if (! IPV4_ADDR_SAME (&next1->gate.ipv4, &next2->gate.ipv4))
	return 0;
      if (next1->ifindex && (next1->ifindex != next2->ifindex))
	return 0;
      break;
    case NEXTHOP_TYPE_IFINDEX:
      if (next1->ifindex != next2->ifindex)
	return 0;
      break;
    case NEXTHOP_TYPE_IPV6:
      if (! IPV6_ADDR_SAME (&next1->gate.ipv6, &next2->gate.ipv6))
	return 0;
      break;
    case NEXTHOP_TYPE_IPV6_IFINDEX:
      if (! IPV6_ADDR_SAME (&next1->gate.ipv6, &next2->gate.ipv6))
	return 0;
      if (next1->ifindex != next2->ifindex)
	return 0;
      break;
    default:
      /* do nothing */
      break;
    }
  return 1;
}

/*
 * nexthop_type_to_str
 */
const char *
nexthop_type_to_str (enum nexthop_types_t nh_type)
{
  static const char *desc[] = {
    "none",
    "Directly connected",
    "IPv4 nexthop",
    "IPv4 nexthop with ifindex",
    "IPv6 nexthop",
    "IPv6 nexthop with ifindex",
    "Null0 nexthop",
  };

  return desc[nh_type];
}

/*
 * Check if the labels match for the 2 nexthops specified.
 */
int
nexthop_labels_match (struct nexthop *nh1, struct nexthop *nh2)
{
  struct nexthop_label *nhl1, *nhl2;

  nhl1 = nh1->nh_label;
  nhl2 = nh2->nh_label;
  if ((nhl1 && !nhl2) || (!nhl1 && nhl2))
    return 0;

  if (nhl1->num_labels != nhl2->num_labels)
    return 0;

  if (memcmp (nhl1->label, nhl2->label, nhl1->num_labels))
    return 0;

  return 1;
}

struct nexthop *
nexthop_new (void)
{
  return XCALLOC (MTYPE_NEXTHOP, sizeof (struct nexthop));
}

/* Add nexthop to the end of a nexthop list.  */
void
nexthop_add (struct nexthop **target, struct nexthop *nexthop)
{
  struct nexthop *last;

  for (last = *target; last && last->next; last = last->next)
    ;
  if (last)
    last->next = nexthop;
  else
    *target = nexthop;
  nexthop->prev = last;
}

void
copy_nexthops (struct nexthop **tnh, struct nexthop *nh)
{
  struct nexthop *nexthop;
  struct nexthop *nh1;

  for (nh1 = nh; nh1; nh1 = nh1->next)
    {
      nexthop = nexthop_new();
      nexthop->flags = nh->flags;
      nexthop->type = nh->type;
      nexthop->ifindex = nh->ifindex;
      memcpy(&(nexthop->gate), &(nh->gate), sizeof(union g_addr));
      memcpy(&(nexthop->src), &(nh->src), sizeof(union g_addr));
      if (nh->nh_label)
        nexthop_add_labels (nexthop, nh->nh_label_type,
			    nh->nh_label->num_labels, &nh->nh_label->label[0]);
      nexthop_add(tnh, nexthop);

      if (CHECK_FLAG(nh1->flags, NEXTHOP_FLAG_RECURSIVE))
	copy_nexthops(&nexthop->resolved, nh1->resolved);
    }
}

/* Free nexthop. */
void
nexthop_free (struct nexthop *nexthop)
{
  nexthop_del_labels (nexthop);
  if (nexthop->resolved)
    nexthops_free(nexthop->resolved);
  XFREE (MTYPE_NEXTHOP, nexthop);
}

/* Frees a list of nexthops */
void
nexthops_free (struct nexthop *nexthop)
{
  struct nexthop *nh, *next;

  for (nh = nexthop; nh; nh = next)
    {
      next = nh->next;
      nexthop_free (nh);
    }
}

/* Update nexthop with label information. */
void
nexthop_add_labels (struct nexthop *nexthop, enum lsp_types_t type,
		    u_int8_t num_labels, mpls_label_t *label)
{
  struct nexthop_label *nh_label;
  int i;

  nexthop->nh_label_type = type;
  nh_label = XCALLOC (MTYPE_NH_LABEL, sizeof (struct nexthop_label) +
		      num_labels * sizeof (mpls_label_t));
  nh_label->num_labels = num_labels;
  for (i = 0; i < num_labels; i++)
    nh_label->label[i] = *(label + i);
  nexthop->nh_label = nh_label;
}

/* Free label information of nexthop, if present. */
void
nexthop_del_labels (struct nexthop *nexthop)
{
  if (nexthop->nh_label)
    {
      XFREE (MTYPE_NH_LABEL, nexthop->nh_label);
      nexthop->nh_label_type = ZEBRA_LSP_NONE;
    }
}

const char *
nexthop2str (struct nexthop *nexthop, char *str, int size)
{
  switch (nexthop->type)
    {
      case NEXTHOP_TYPE_IFINDEX:
        snprintf (str, size, "if %u", nexthop->ifindex);
        break;
      case NEXTHOP_TYPE_IPV4:
        snprintf (str, size, "%s", inet_ntoa (nexthop->gate.ipv4));
        break;
      case NEXTHOP_TYPE_IPV4_IFINDEX:
        snprintf (str, size, "%s if %u",
                  inet_ntoa (nexthop->gate.ipv4), nexthop->ifindex);
        break;
      case NEXTHOP_TYPE_IPV6:
        snprintf (str, size, "%s", inet6_ntoa (nexthop->gate.ipv6));
        break;
      case NEXTHOP_TYPE_IPV6_IFINDEX:
        snprintf (str, size, "%s if %u",
                  inet6_ntoa (nexthop->gate.ipv6), nexthop->ifindex);
        break;
      case NEXTHOP_TYPE_BLACKHOLE:
        snprintf (str, size, "blackhole");
        break;
      default:
        snprintf (str, size, "unknown");
        break;
    }

  return str;
}