path: root/pimd/pim_zlookup.c

/*
 * PIM for Quagga
 * Copyright (C) 2008  Everton da Silva Marques
 *
 * This program 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 of the License, or
 * (at your option) any later version.
 *
 * This program 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
 */

#include <zebra.h>
#include "zebra/rib.h"

#include "log.h"
#include "prefix.h"
#include "zclient.h"
#include "stream.h"
#include "network.h"
#include "thread.h"
#include "prefix.h"
#include "vty.h"

#include "pimd.h"
#include "pim_iface.h"
#include "pim_pim.h"
#include "pim_str.h"
#include "pim_oil.h"
#include "pim_zlookup.h"

static struct zclient *zlookup = NULL;

static void zclient_lookup_sched(struct zclient *zlookup, int delay);

/* Connect to zebra for nexthop lookup. */
static int zclient_lookup_connect(struct thread *t)
{
  struct zclient *zlookup;

  zlookup = THREAD_ARG(t);
  zlookup->t_connect = NULL;

  if (zlookup->sock >= 0) {
    return 0;
  }

  if (zclient_socket_connect(zlookup) < 0) {
    ++zlookup->fail;
    zlog_warn("%s: failure connecting zclient socket: failures=%d",
	      __PRETTY_FUNCTION__, zlookup->fail);
  }
  else {
    zlookup->fail = 0; /* reset counter on connection */
  }

  zassert(!zlookup->t_connect);
  if (zlookup->sock < 0) {
    /* Since last connect failed, retry within 10 secs */
    zclient_lookup_sched(zlookup, 10);
    return -1;
  }

  return 0;
}

/* Schedule connection with delay. */
static void zclient_lookup_sched(struct zclient *zlookup, int delay)
{
  zassert(!zlookup->t_connect);

  thread_add_timer(master, zclient_lookup_connect, zlookup, delay,
                   &zlookup->t_connect);

  zlog_notice("%s: zclient lookup connection scheduled for %d seconds",
	      __PRETTY_FUNCTION__, delay);
}

/* Schedule connection for now. */
static void zclient_lookup_sched_now(struct zclient *zlookup)
{
  zassert(!zlookup->t_connect);
  thread_add_event(master, zclient_lookup_connect, zlookup, 0,
                   &zlookup->t_connect);

  zlog_notice("%s: zclient lookup immediate connection scheduled",
	      __PRETTY_FUNCTION__);
}

/* Schedule reconnection, if needed. */
static void zclient_lookup_reconnect(struct zclient *zlookup)
{
  if (zlookup->t_connect) {
    return;
  }

  zclient_lookup_sched_now(zlookup);
}

static void zclient_lookup_failed(struct zclient *zlookup)
{
  if (zlookup->sock >= 0) {
    if (close(zlookup->sock)) {
      zlog_warn("%s: closing fd=%d: errno=%d %s", __func__, zlookup->sock,
		errno, safe_strerror(errno));
    }
    zlookup->sock = -1;
  }

  zclient_lookup_reconnect(zlookup);
}

void
zclient_lookup_free (void)
{
  zclient_free (zlookup);
  zlookup = NULL;
}

void
zclient_lookup_new (void)
{
  zlookup = zclient_new (master);
  if (!zlookup) {
    zlog_err("%s: zclient_new() failure",
	     __PRETTY_FUNCTION__);
    return;
  }

  zlookup->sock = -1;
  zlookup->t_connect = NULL;

  zclient_lookup_sched_now(zlookup);

  zlog_notice("%s: zclient lookup socket initialized",
	      __PRETTY_FUNCTION__);

}

static int zclient_read_nexthop(struct zclient *zlookup,
				struct pim_zlookup_nexthop nexthop_tab[],
				const int tab_size,
				struct in_addr addr)
{
  int num_ifindex = 0;
  struct stream *s;
  const uint16_t MIN_LEN = 10; /* getipv4=4 getc=1 getl=4 getc=1 */
  uint16_t length;
  u_char marker;
  u_char version;
  vrf_id_t vrf_id;
  uint16_t command = 0;
  struct in_addr raddr;
  uint8_t distance;
  uint32_t metric;
  int nexthop_num;
  int i, err;

  if (PIM_DEBUG_PIM_TRACE_DETAIL) {
    char addr_str[INET_ADDRSTRLEN];
    pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
    zlog_debug("%s: addr=%s", 
	       __PRETTY_FUNCTION__,
	       addr_str);
  }

  s = zlookup->ibuf;

  while (command != ZEBRA_IPV4_NEXTHOP_LOOKUP_MRIB)
    {
      stream_reset(s);
      err = zclient_read_header (s, zlookup->sock, &length, &marker, &version,
				 &vrf_id, &command);
      if (err < 0) {
	zlog_err("%s %s: zclient_read_header() failed",
		 __FILE__, __PRETTY_FUNCTION__);
	zclient_lookup_failed(zlookup);
	return -1;
      }

      if (length < MIN_LEN) {
	zlog_err("%s %s: failure reading zclient lookup socket: len=%d < MIN_LEN=%d",
		 __FILE__, __PRETTY_FUNCTION__, length, MIN_LEN);
	zclient_lookup_failed(zlookup);
	return -2;
      }
    }

  raddr.s_addr = stream_get_ipv4(s);

  if (raddr.s_addr != addr.s_addr) {
    char addr_str[INET_ADDRSTRLEN];
    char raddr_str[INET_ADDRSTRLEN];
    pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
    pim_inet4_dump("<raddr?>", raddr, raddr_str, sizeof(raddr_str));
    zlog_warn("%s: address mismatch: addr=%s raddr=%s", 
	       __PRETTY_FUNCTION__,
	       addr_str, raddr_str);
    /* warning only */
  }

  distance = stream_getc(s);
  metric = stream_getl(s);
  nexthop_num = stream_getc(s);

  if (nexthop_num < 1) {
    zlog_err("%s: socket %d bad nexthop_num=%d",
            __func__, zlookup->sock, nexthop_num);
    return -6;
  }

  for (i = 0; i < nexthop_num; ++i) {
    enum nexthop_types_t nexthop_type;
    struct pim_neighbor *nbr;
    struct prefix p;

    nexthop_type = stream_getc(s);
    if (num_ifindex >= tab_size) {
      char addr_str[INET_ADDRSTRLEN];
      pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
      zlog_warn("%s %s: found too many nexthop ifindexes (%d > %d) for address %s",
		__FILE__, __PRETTY_FUNCTION__,
		(num_ifindex + 1), tab_size, addr_str);
      return num_ifindex;
    }
    switch (nexthop_type) {
    case NEXTHOP_TYPE_IFINDEX:
    case NEXTHOP_TYPE_IPV4_IFINDEX:
    case NEXTHOP_TYPE_IPV4:
      nexthop_tab[num_ifindex].nexthop_addr.family = AF_INET;
      if (nexthop_type == NEXTHOP_TYPE_IPV4_IFINDEX ||
	  nexthop_type == NEXTHOP_TYPE_IPV4) {
	nexthop_tab[num_ifindex].nexthop_addr.u.prefix4.s_addr = stream_get_ipv4(s);
      }
      else {
	nexthop_tab[num_ifindex].nexthop_addr.u.prefix4.s_addr = PIM_NET_INADDR_ANY;
      }
      nexthop_tab[num_ifindex].ifindex           = stream_getl(s);
      nexthop_tab[num_ifindex].protocol_distance = distance;
      nexthop_tab[num_ifindex].route_metric      = metric;
      ++num_ifindex;
      break;
    case NEXTHOP_TYPE_IPV6_IFINDEX:
      nexthop_tab[num_ifindex].nexthop_addr.family = AF_INET6;
      stream_get (&nexthop_tab[num_ifindex].nexthop_addr.u.prefix6,
		  s,
		  sizeof(struct in6_addr));
      nexthop_tab[num_ifindex].ifindex = stream_getl (s);

      p.family = AF_INET6;
      p.prefixlen = IPV6_MAX_PREFIXLEN;
      memcpy (&p.u.prefix6,
	      &nexthop_tab[num_ifindex].nexthop_addr.u.prefix6,
	      sizeof(struct in6_addr));

      /*
       * If we are sending v6 secondary assume we receive v6 secondary
       */
      if (pimg->send_v6_secondary)
        nbr = pim_neighbor_find_by_secondary(if_lookup_by_index (nexthop_tab[num_ifindex].ifindex, VRF_DEFAULT), &p);
      else
        nbr = pim_neighbor_find_if (if_lookup_by_index (nexthop_tab[num_ifindex].ifindex, VRF_DEFAULT));
      if (nbr)
        {
          nexthop_tab[num_ifindex].nexthop_addr.family = AF_INET;
          nexthop_tab[num_ifindex].nexthop_addr.u.prefix4 = nbr->source_addr;
        }
        ++num_ifindex;
      break;
    default:
      /* do nothing */
      {
	char addr_str[INET_ADDRSTRLEN];
	pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
	zlog_warn("%s %s: found non-ifindex nexthop type=%d for address %s",
		 __FILE__, __PRETTY_FUNCTION__,
		  nexthop_type, addr_str);
      }
      break;
    }
  }

  return num_ifindex;
}

static int
zclient_lookup_nexthop_once (struct pim_zlookup_nexthop nexthop_tab[],
			     const int tab_size,
			     struct in_addr addr)
{
  struct stream *s;
  int ret;

  if (PIM_DEBUG_PIM_TRACE_DETAIL) {
    char addr_str[INET_ADDRSTRLEN];
    pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
    zlog_debug("%s: addr=%s", 
	       __PRETTY_FUNCTION__,
	       addr_str);
  }

  /* Check socket. */
  if (zlookup->sock < 0) {
    zlog_err("%s %s: zclient lookup socket is not connected",
	     __FILE__, __PRETTY_FUNCTION__);
    zclient_lookup_failed(zlookup);
    return -1;
  }
  
  s = zlookup->obuf;
  stream_reset(s);
  zclient_create_header(s, ZEBRA_IPV4_NEXTHOP_LOOKUP_MRIB, VRF_DEFAULT);
  stream_put_in_addr(s, &addr);
  stream_putw_at(s, 0, stream_get_endp(s));
  
  ret = writen(zlookup->sock, s->data, stream_get_endp(s));
  if (ret < 0) {
    zlog_err("%s %s: writen() failure: %d writing to zclient lookup socket",
	     __FILE__, __PRETTY_FUNCTION__, errno);
    zclient_lookup_failed(zlookup);
    return -2;
  }
  if (ret == 0) {
    zlog_err("%s %s: connection closed on zclient lookup socket",
	     __FILE__, __PRETTY_FUNCTION__);
    zclient_lookup_failed(zlookup);
    return -3;
  }
  
  return zclient_read_nexthop(zlookup, nexthop_tab,
			      tab_size, addr);
}

int
zclient_lookup_nexthop (struct pim_zlookup_nexthop nexthop_tab[],
			const int tab_size,
			struct in_addr addr,
			int max_lookup)
{
  int lookup;
  uint32_t route_metric = 0xFFFFFFFF;
  uint8_t  protocol_distance = 0xFF;

  qpim_nexthop_lookups++;

  for (lookup = 0; lookup < max_lookup; ++lookup) {
    int num_ifindex;
    int first_ifindex;
    struct prefix nexthop_addr;

    num_ifindex = zclient_lookup_nexthop_once(nexthop_tab,
					      tab_size, addr);
    if (num_ifindex < 1) {
      if (PIM_DEBUG_ZEBRA) {
	char addr_str[INET_ADDRSTRLEN];
	pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
	zlog_debug("%s %s: lookup=%d/%d: could not find nexthop ifindex for address %s",
		   __FILE__, __PRETTY_FUNCTION__,
		   lookup, max_lookup, addr_str);
      }
      return -1;
    }

    if (lookup < 1) {
      /* this is the non-recursive lookup - save original metric/distance */
      route_metric = nexthop_tab[0].route_metric;
      protocol_distance = nexthop_tab[0].protocol_distance;
    }
    
    /*
     * FIXME: Non-recursive nexthop ensured only for first ifindex.
     * However, recursive route lookup should really be fixed in zebra daemon.
     * See also TODO T24.
     *
     * So Zebra for NEXTHOP_TYPE_IPV4 returns the ifindex now since
     * it was being stored.  This Doesn't solve all cases of
     * recursive lookup but for the most common types it does.
     */
    first_ifindex = nexthop_tab[0].ifindex;
    nexthop_addr = nexthop_tab[0].nexthop_addr;
    if (first_ifindex > 0) {
      /* found: first ifindex is non-recursive nexthop */

      if (lookup > 0) {
	/* Report non-recursive success after first lookup */
	if (PIM_DEBUG_ZEBRA) {
	  char addr_str[INET_ADDRSTRLEN];
	  pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
	  zlog_debug("%s %s: lookup=%d/%d: found non-recursive ifindex=%d for address %s dist=%d met=%d",
		     __FILE__, __PRETTY_FUNCTION__,
		     lookup, max_lookup, first_ifindex, addr_str,
		     nexthop_tab[0].protocol_distance,
		     nexthop_tab[0].route_metric);
	}

	/* use last address as nexthop address */
	nexthop_tab[0].nexthop_addr.u.prefix4 = addr;

	/* report original route metric/distance */
	nexthop_tab[0].route_metric = route_metric;
	nexthop_tab[0].protocol_distance = protocol_distance;
      }

      return num_ifindex;
    }

    if (PIM_DEBUG_ZEBRA) {
      char addr_str[INET_ADDRSTRLEN];
      char nexthop_str[PREFIX_STRLEN];
      pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
      pim_addr_dump("<nexthop?>", &nexthop_addr, nexthop_str, sizeof(nexthop_str));
      zlog_debug("%s %s: lookup=%d/%d: zebra returned recursive nexthop %s for address %s dist=%d met=%d",
		__FILE__, __PRETTY_FUNCTION__,
		lookup, max_lookup, nexthop_str, addr_str,
		nexthop_tab[0].protocol_distance,
		nexthop_tab[0].route_metric);
    }

    addr = nexthop_addr.u.prefix4; /* use nexthop addr for recursive lookup */

  } /* for (max_lookup) */

  if (PIM_DEBUG_ZEBRA) {
    char addr_str[INET_ADDRSTRLEN];
    pim_inet4_dump("<addr?>", addr, addr_str, sizeof(addr_str));
    zlog_warn("%s %s: lookup=%d/%d: failure searching recursive nexthop ifindex for address %s",
	      __FILE__, __PRETTY_FUNCTION__,
	      lookup, max_lookup, addr_str);
  }

  return -2;
}

void
pim_zlookup_show_ip_multicast (struct vty *vty)
{
  vty_out(vty, "Zclient lookup socket: ");
  if (zlookup) {
    vty_out(vty, "%d failures=%d%s", zlookup->sock,
            zlookup->fail, VTY_NEWLINE);
  }
  else {
    vty_out(vty, "<null zclient>%s", VTY_NEWLINE);
  }
}

int
pim_zlookup_sg_statistics (struct channel_oil *c_oil)
{
  struct stream *s = zlookup->obuf;
  uint16_t command = 0;
  unsigned long long lastused;
  struct prefix_sg sg;
  int count = 0;
  int ret;
  struct interface *ifp = pim_if_find_by_vif_index (c_oil->oil.mfcc_parent);

  if (PIM_DEBUG_ZEBRA)
    {
      struct prefix_sg more;

      more.src = c_oil->oil.mfcc_origin;
      more.grp = c_oil->oil.mfcc_mcastgrp;
      zlog_debug ("Sending Request for New Channel Oil Information(%s) VIIF %d",
            pim_str_sg_dump (&more), c_oil->oil.mfcc_parent);
    }

  if (!ifp)
    return -1;

  stream_reset (s);
  zclient_create_header (s, ZEBRA_IPMR_ROUTE_STATS, VRF_DEFAULT);
  stream_put_in_addr (s, &c_oil->oil.mfcc_origin);
  stream_put_in_addr (s, &c_oil->oil.mfcc_mcastgrp);
  stream_putl (s,  ifp->ifindex);
  stream_putw_at(s, 0, stream_get_endp(s));

  count = stream_get_endp (s);
  ret = writen (zlookup->sock, s->data, count);
  if (ret <= 0)
    {
      zlog_err("%s %s: writen() failure: %d writing to zclient lookup socket",
               __FILE__, __PRETTY_FUNCTION__, errno);
      return -1;
    }

  s = zlookup->ibuf;

  while (command != ZEBRA_IPMR_ROUTE_STATS)
    {
      int err;
      uint16_t length = 0;
      vrf_id_t vrf_id;
      u_char marker;
      u_char version;

      stream_reset (s);
      err = zclient_read_header (s, zlookup->sock, &length, &marker, &version,
				 &vrf_id, &command);
      if (err < 0)
        {
          zlog_err ("%s %s: zclient_read_header() failed",
                 __FILE__, __PRETTY_FUNCTION__);
        zclient_lookup_failed(zlookup);
        return -1;
        }
    }

  sg.src.s_addr = stream_get_ipv4 (s);
  sg.grp.s_addr = stream_get_ipv4 (s);
  if (sg.src.s_addr != c_oil->oil.mfcc_origin.s_addr ||
      sg.grp.s_addr != c_oil->oil.mfcc_mcastgrp.s_addr)
    {
       zlog_err ("%s: Received wrong %s information",
		 __PRETTY_FUNCTION__, pim_str_sg_dump (&sg));
       zclient_lookup_failed (zlookup);
       return -3;
    }

  stream_get (&lastused, s, sizeof (lastused));
  ret = stream_getl (s);

  if (PIM_DEBUG_ZEBRA)
    zlog_debug ("Received %lld for %s success: %d", lastused, pim_str_sg_dump (&sg), ret);

  c_oil->cc.lastused = lastused;

  return 0;

}