[mirror_frr.git] / pimd / pim_register.c

/*
 * PIM for Quagga
 * Copyright (C) 2015 Cumulus Networks, Inc.
 * Donald Sharp
 *
 * 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 "log.h"
#include "if.h"
#include "thread.h"
#include "prefix.h"
#include "vty.h"
#include "plist.h"

#include "pimd.h"
#include "pim_mroute.h"
#include "pim_iface.h"
#include "pim_msg.h"
#include "pim_pim.h"
#include "pim_str.h"
#include "pim_rp.h"
#include "pim_register.h"
#include "pim_upstream.h"
#include "pim_br.h"
#include "pim_rpf.h"
#include "pim_oil.h"
#include "pim_zebra.h"
#include "pim_join.h"
#include "pim_util.h"

struct thread *send_test_packet_timer = NULL;

void
pim_register_stop_send (struct interface *ifp, struct prefix_sg *sg,
			struct in_addr src, struct in_addr originator)
{
  struct pim_interface *pinfo;
  unsigned char buffer[10000];
  unsigned int b1length = 0;
  unsigned int length;
  uint8_t *b1;
  struct prefix p;

  if (PIM_DEBUG_PIM_REG)
    {
      zlog_debug ("Sending Register stop for %s to %s on %s",
		  pim_str_sg_dump (sg), inet_ntoa(originator), ifp->name);
    }

  memset (buffer, 0, 10000);
  b1 = (uint8_t *)buffer + PIM_MSG_REGISTER_STOP_LEN;

  length = pim_encode_addr_group (b1, AFI_IP, 0, 0, sg->grp);
  b1length += length;
  b1 += length;

  p.family = AF_INET;
  p.u.prefix4 = sg->src;
  p.prefixlen = 32;
  length = pim_encode_addr_ucast (b1, &p);
  b1length += length;

  pim_msg_build_header (buffer, b1length + PIM_MSG_REGISTER_STOP_LEN, PIM_MSG_TYPE_REG_STOP);

  pinfo = (struct pim_interface *)ifp->info;
  if (!pinfo)
    {
      if (PIM_DEBUG_PIM_TRACE)
        zlog_debug ("%s: No pinfo!\n", __PRETTY_FUNCTION__);
      return;
    }
  if (pim_msg_send (pinfo->pim_sock_fd, src, originator,
		    buffer, b1length + PIM_MSG_REGISTER_STOP_LEN,
		    ifp->name))
    {
      if (PIM_DEBUG_PIM_TRACE)
	{
	  zlog_debug ("%s: could not send PIM register stop message on interface %s",
		      __PRETTY_FUNCTION__, ifp->name);
	}
    }
}

int
pim_register_stop_recv (uint8_t *buf, int buf_size)
{
  struct pim_upstream *upstream = NULL;
  struct prefix source;
  struct prefix_sg sg;
  int l;

  memset (&sg, 0, sizeof (struct prefix_sg));
  l = pim_parse_addr_group (&sg, buf, buf_size);
  buf += l;
  buf_size -= l;
  pim_parse_addr_ucast (&source, buf, buf_size);
  sg.src = source.u.prefix4;

  if (PIM_DEBUG_PIM_REG)
    {
      zlog_debug ("Received Register stop for %s",
		  pim_str_sg_dump (&sg));
    }

  upstream = pim_upstream_find (&sg);
  if (!upstream)
    {
      return 0;
    }

  switch (upstream->join_state)
    {
    case PIM_UPSTREAM_NOTJOINED:
    case PIM_UPSTREAM_PRUNE:
      return 0;
      break;
    case PIM_UPSTREAM_JOINED:
      upstream->join_state = PIM_UPSTREAM_PRUNE;
      pim_channel_del_oif (upstream->channel_oil, pim_regiface, PIM_OIF_FLAG_PROTO_PIM);
      pim_upstream_start_register_stop_timer (upstream, 0);
    case PIM_UPSTREAM_JOIN_PENDING:
      upstream->join_state = PIM_UPSTREAM_PRUNE;
      pim_upstream_start_register_stop_timer (upstream, 0);
      return 0;
      break;
    }

  return 0;
}

void
pim_register_send (const uint8_t *buf, int buf_size, struct in_addr src, struct pim_rpf *rpg, int null_register, struct pim_upstream *up)
{
  unsigned char buffer[10000];
  unsigned char *b1;
  struct pim_interface *pinfo;
  struct interface *ifp;

  if (PIM_DEBUG_PIM_REG)
    {
       char rp_str[INET_ADDRSTRLEN];
       strcpy (rp_str, inet_ntoa (rpg->rpf_addr.u.prefix4));
       zlog_debug ("Sending %s %sRegister Packet to %s",
		   pim_str_sg_dump (&up->sg), null_register ? "NULL " : "", rp_str);
    }

  ifp = rpg->source_nexthop.interface;
  if (!ifp)
    {
      if (PIM_DEBUG_PIM_REG)
        zlog_debug ("%s: No interface to transmit register on", __PRETTY_FUNCTION__);
      return;
    }
  pinfo = (struct pim_interface *)ifp->info;
  if (!pinfo) {
    if (PIM_DEBUG_PIM_REG)
      zlog_debug("%s: Interface: %s not configured for pim to trasmit on!\n", __PRETTY_FUNCTION__, ifp->name);
    return;
  }

  memset(buffer, 0, 10000);
  b1 = buffer + PIM_MSG_HEADER_LEN;
  *b1 |= null_register << 6;
  b1 = buffer + PIM_MSG_REGISTER_LEN;

  memcpy(b1, (const unsigned char *)buf, buf_size);

  pim_msg_build_header(buffer, buf_size + PIM_MSG_REGISTER_LEN, PIM_MSG_TYPE_REGISTER);

  if (pim_msg_send(pinfo->pim_sock_fd,
		   src,
		   rpg->rpf_addr.u.prefix4,
		   buffer,
		   buf_size + PIM_MSG_REGISTER_LEN,
		   ifp->name)) {
    if (PIM_DEBUG_PIM_TRACE) {
      zlog_debug("%s: could not send PIM register message on interface %s",
		 __PRETTY_FUNCTION__, ifp->name);
    }
    return;
  }
}

/*
 * 4.4.2 Receiving Register Messages at the RP
 *
 *   When an RP receives a Register message, the course of action is
 *  decided according to the following pseudocode:
 *
 *  packet_arrives_on_rp_tunnel( pkt ) {
 *      if( outer.dst is not one of my addresses ) {
 *          drop the packet silently.
 *          # Note: this may be a spoofing attempt
 *      }
 *      if( I_am_RP(G) AND outer.dst == RP(G) ) {
 *            sentRegisterStop = FALSE;
 *            if ( register.borderbit == TRUE ) {
 *                 if ( PMBR(S,G) == unknown ) {
 *                      PMBR(S,G) = outer.src
 *                 } else if ( outer.src != PMBR(S,G) ) {
 *                      send Register-Stop(S,G) to outer.src
 *                      drop the packet silently.
 *                 }
 *            }
 *            if ( SPTbit(S,G) OR
 *             ( SwitchToSptDesired(S,G) AND
 *               ( inherited_olist(S,G) == NULL ))) {
 *              send Register-Stop(S,G) to outer.src
 *              sentRegisterStop = TRUE;
 *            }
 *            if ( SPTbit(S,G) OR SwitchToSptDesired(S,G) ) {
 *                 if ( sentRegisterStop == TRUE ) {
 *                      set KeepaliveTimer(S,G) to RP_Keepalive_Period;
 *                 } else {
 *                      set KeepaliveTimer(S,G) to Keepalive_Period;
 *                 }
 *            }
 *            if( !SPTbit(S,G) AND ! pkt.NullRegisterBit ) {
 *                 decapsulate and forward the inner packet to
 *                 inherited_olist(S,G,rpt) # Note (+)
 *            }
 *      } else {
 *          send Register-Stop(S,G) to outer.src
 *          # Note (*)
 *      }
 *  }
 */
int
pim_register_recv (struct interface *ifp,
		   struct in_addr dest_addr,
		   struct in_addr src_addr,
		   uint8_t *tlv_buf, int tlv_buf_size)
{
  int sentRegisterStop = 0;
  struct ip *ip_hdr;
  struct prefix_sg sg;
  uint32_t *bits;
  int i_am_rp = 0;

#define PIM_MSG_REGISTER_BIT_RESERVED_LEN 4
  ip_hdr = (struct ip *)(tlv_buf + PIM_MSG_REGISTER_BIT_RESERVED_LEN);

  if (!pim_rp_check_is_my_ip_address (ip_hdr->ip_dst, dest_addr)) {
    if (PIM_DEBUG_PIM_REG) {
      char dest[INET_ADDRSTRLEN];

      pim_inet4_dump ("<dst?>", dest_addr, dest, sizeof(dest));
      zlog_debug ("%s: Received Register message for %s that I do not own", __func__,
		  dest);
    }
    return 0;
  }

  /*
   * Please note this is not drawn to get the correct bit/data size
   *
   * The entirety of the REGISTER packet looks like this:
   * -------------------------------------------------------------
   * | Ver  | Type | Reserved     |       Checksum               |
   * |-----------------------------------------------------------|
   * |B|N|     Reserved 2                                        |
   * |-----------------------------------------------------------|
   * | Encap  |                IP HDR                            |
   * | Mcast  |                                                  |
   * | Packet |--------------------------------------------------|
   * |        |               Mcast Data                         |
   * |        |                                                  |
   * ...
   *
   * tlv_buf when received from the caller points at the B bit
   * We need to know the inner source and dest
   */
  bits = (uint32_t *)tlv_buf;

  /*
   * tlv_buf points to the start of the |B|N|... Reserved
   * Line above.  So we need to add 4 bytes to get to the
   * start of the actual Encapsulated data.
   */
  memset (&sg, 0, sizeof (struct prefix_sg));
  sg.src = ip_hdr->ip_src;
  sg.grp = ip_hdr->ip_dst;

  i_am_rp = I_am_RP (sg.grp);

  if (PIM_DEBUG_PIM_REG)
    {
      char src_str[INET_ADDRSTRLEN];

      pim_inet4_dump ("<src?>", src_addr, src_str, sizeof (src_str));
      zlog_debug ("Received Register message(%s) from %s on %s, rp: %d",
                  pim_str_sg_dump (&sg), src_str, ifp->name, i_am_rp);
    }

  if (i_am_rp && (dest_addr.s_addr == ((RP (sg.grp))->rpf_addr.u.prefix4.s_addr))) {
    sentRegisterStop = 0;

    if (*bits & PIM_REGISTER_BORDER_BIT) {
      struct in_addr pimbr = pim_br_get_pmbr (&sg);
      if (PIM_DEBUG_PIM_PACKETS)
	zlog_debug("%s: Received Register message with Border bit set", __func__);

      if (pimbr.s_addr == pim_br_unknown.s_addr)
	pim_br_set_pmbr(&sg, src_addr);
      else if (src_addr.s_addr != pimbr.s_addr) {
	pim_register_stop_send (ifp, &sg, dest_addr, src_addr);
	if (PIM_DEBUG_PIM_PACKETS)
	  zlog_debug("%s: Sending register-Stop to %s and dropping mr. packet",
	    __func__, "Sender");
	/* Drop Packet Silently */
	return 1;
      }
    }

    struct pim_upstream *upstream = pim_upstream_find (&sg);
    /*
     * If we don't have a place to send ignore the packet
     */
    if (!upstream)
      {
	upstream = pim_upstream_add (&sg, ifp,
				     PIM_UPSTREAM_FLAG_MASK_SRC_STREAM,
				     __PRETTY_FUNCTION__);
        if (!upstream)
          {
            zlog_warn ("Failure to create upstream state");
            return 1;
          }
        PIM_UPSTREAM_FLAG_SET_SRC_STREAM(upstream->flags);

        upstream->upstream_register = src_addr;
	pim_rp_set_upstream_addr (&upstream->upstream_addr, sg.src, sg.grp);
	if (pim_nexthop_lookup (&upstream->rpf.source_nexthop,
			        upstream->upstream_addr, 1) != 0)
          {
            if (PIM_DEBUG_PIM_REG)
              {
                zlog_debug ("Received Register(%s), for which I have no path back", pim_str_sg_dump (&upstream->sg));
              }
            PIM_UPSTREAM_FLAG_UNSET_SRC_STREAM(upstream->flags);
            pim_upstream_del (upstream, __PRETTY_FUNCTION__);
            return 1;
          }
	upstream->sg.src = sg.src;
	upstream->rpf.rpf_addr = upstream->rpf.source_nexthop.mrib_nexthop_addr;

	upstream->join_state = PIM_UPSTREAM_PRUNE;

      }

    if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) ||
	((SwitchToSptDesired(&sg)) &&
	 pim_upstream_inherited_olist (upstream) == 0)) {
      //pim_scan_individual_oil (upstream->channel_oil);
      pim_register_stop_send (ifp, &sg, dest_addr, src_addr);
      sentRegisterStop = 1;
    } else {
      if (PIM_DEBUG_PIM_REG)
         zlog_debug ("(%s) sptbit: %d", pim_str_sg_dump (&upstream->sg), upstream->sptbit);
    }
    if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) ||
	(SwitchToSptDesired(&sg))) {
      if (sentRegisterStop) {
	pim_upstream_keep_alive_timer_start (upstream, qpim_rp_keep_alive_time);
      } else {
	pim_upstream_keep_alive_timer_start (upstream, qpim_keep_alive_time);
      }
    }

    if (!(upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) &&
	!(*bits & PIM_REGISTER_NR_BIT))
      {
	//decapsulate and forward the iner packet to
	//inherited_olist(S,G,rpt)
	// This is taken care of by the kernel for us
      }
     pim_upstream_msdp_reg_timer_start(upstream);
  } else {
    if (PIM_DEBUG_PIM_REG)
      {
	if (!i_am_rp)
	  zlog_debug ("Received Register packet for %s, Rejecting packet because I am not the RP configured for group",
		      pim_str_sg_dump (&sg));
	else
	  zlog_debug ("Received Register packet for %s, Rejecting packet because the dst ip address is not the actual RP",
		      pim_str_sg_dump (&sg));
      }
    pim_register_stop_send (ifp, &sg, dest_addr, src_addr);
  }

  return 1;
}
Commit	Line	Data
01d68c9b DS	1	/*
	2	* PIM for Quagga
	3	* Copyright (C) 2015 Cumulus Networks, Inc.
	4	* Donald Sharp
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful, but
	12	* WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	* General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; see the file COPYING; if not, write to the
	18	* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
	19	* MA 02110-1301 USA
	20	*/
	21
	22	#include <zebra.h>
	23
	24	#include "log.h"
	25	#include "if.h"
	26	#include "thread.h"
13c2408c	27	#include "prefix.h"
dfe43e25 DW	28	#include "vty.h"
dfe43e25 DW	29	#include "plist.h"
01d68c9b DS	30
01d68c9b DS	31	#include "pimd.h"
998af219 DS	32	#include "pim_mroute.h"
	33	#include "pim_iface.h"
	34	#include "pim_msg.h"
	35	#include "pim_pim.h"
01d68c9b DS	36	#include "pim_str.h"
	37	#include "pim_rp.h"
	38	#include "pim_register.h"
80c0d168	39	#include "pim_upstream.h"
01d68c9b	40	#include "pim_br.h"
2ca35b3d DS	41	#include "pim_rpf.h"
	42	#include "pim_oil.h"
	43	#include "pim_zebra.h"
	44	#include "pim_join.h"
13c2408c	45	#include "pim_util.h"
01d68c9b DS	46
	47	struct thread *send_test_packet_timer = NULL;
	48
8e38a2cf	49	void
4ed0af70	50	pim_register_stop_send (struct interface ifp, struct prefix_sg sg,
4df01a4e	51	struct in_addr src, struct in_addr originator)
01d68c9b	52	{
13c2408c	53	struct pim_interface *pinfo;
19e55095	54	unsigned char buffer[10000];
13c2408c DS	55	unsigned int b1length = 0;
	56	unsigned int length;
	57	uint8_t *b1;
	58	struct prefix p;
	59
9add3b88 DS	60	if (PIM_DEBUG_PIM_REG)
	61	{
	62	zlog_debug ("Sending Register stop for %s to %s on %s",
	63	pim_str_sg_dump (sg), inet_ntoa(originator), ifp->name);
	64	}
	65
19e55095	66	memset (buffer, 0, 10000);
13c2408c DS	67	b1 = (uint8_t *)buffer + PIM_MSG_REGISTER_STOP_LEN;
13c2408c DS	68
4ed0af70	69	length = pim_encode_addr_group (b1, AFI_IP, 0, 0, sg->grp);
13c2408c DS	70	b1length += length;
	71	b1 += length;
	72
	73	p.family = AF_INET;
4ed0af70	74	p.u.prefix4 = sg->src;
13c2408c DS	75	p.prefixlen = 32;
	76	length = pim_encode_addr_ucast (b1, &p);
	77	b1length += length;
	78
	79	pim_msg_build_header (buffer, b1length + PIM_MSG_REGISTER_STOP_LEN, PIM_MSG_TYPE_REG_STOP);
	80
	81	pinfo = (struct pim_interface *)ifp->info;
	82	if (!pinfo)
	83	{
	84	if (PIM_DEBUG_PIM_TRACE)
	85	zlog_debug ("%s: No pinfo!\n", __PRETTY_FUNCTION__);
	86	return;
	87	}
4df01a4e	88	if (pim_msg_send (pinfo->pim_sock_fd, src, originator,
13c2408c DS	89	buffer, b1length + PIM_MSG_REGISTER_STOP_LEN,
	90	ifp->name))
	91	{
	92	if (PIM_DEBUG_PIM_TRACE)
	93	{
	94	zlog_debug ("%s: could not send PIM register stop message on interface %s",
	95	__PRETTY_FUNCTION__, ifp->name);
	96	}
	97	}
01d68c9b DS	98	}
01d68c9b DS	99
4dffc880	100	int
56638739	101	pim_register_stop_recv (uint8_t *buf, int buf_size)
4dffc880	102	{
56638739 DS	103	struct pim_upstream *upstream = NULL;
56638739 DS	104	struct prefix source;
4ed0af70	105	struct prefix_sg sg;
56638739 DS	106	int l;
56638739 DS	107
53e39e14	108	memset (&sg, 0, sizeof (struct prefix_sg));
bce0e645	109	l = pim_parse_addr_group (&sg, buf, buf_size);
56638739 DS	110	buf += l;
56638739 DS	111	buf_size -= l;
a878ba45	112	pim_parse_addr_ucast (&source, buf, buf_size);
4ed0af70	113	sg.src = source.u.prefix4;
9add3b88 DS	114
	115	if (PIM_DEBUG_PIM_REG)
	116	{
	117	zlog_debug ("Received Register stop for %s",
	118	pim_str_sg_dump (&sg));
	119	}
	120
5074a423	121	upstream = pim_upstream_find (&sg);
56638739 DS	122	if (!upstream)
	123	{
	124	return 0;
	125	}
	126
	127	switch (upstream->join_state)
	128	{
	129	case PIM_UPSTREAM_NOTJOINED:
	130	case PIM_UPSTREAM_PRUNE:
	131	return 0;
	132	break;
	133	case PIM_UPSTREAM_JOINED:
bb027ee8 DS	134	upstream->join_state = PIM_UPSTREAM_PRUNE;
	135	pim_channel_del_oif (upstream->channel_oil, pim_regiface, PIM_OIF_FLAG_PROTO_PIM);
	136	pim_upstream_start_register_stop_timer (upstream, 0);
56638739 DS	137	case PIM_UPSTREAM_JOIN_PENDING:
	138	upstream->join_state = PIM_UPSTREAM_PRUNE;
	139	pim_upstream_start_register_stop_timer (upstream, 0);
56638739 DS	140	return 0;
	141	break;
	142	}
	143
4dffc880 DS	144	return 0;
	145	}
	146
998af219	147	void
0e3b3d5d	148	pim_register_send (const uint8_t buf, int buf_size, struct in_addr src, struct pim_rpf rpg, int null_register, struct pim_upstream *up)
998af219	149	{
19e55095	150	unsigned char buffer[10000];
998af219 DS	151	unsigned char *b1;
	152	struct pim_interface *pinfo;
	153	struct interface *ifp;
998af219	154
9add3b88 DS	155	if (PIM_DEBUG_PIM_REG)
9add3b88 DS	156	{
eaa54bdb	157	char rp_str[INET_ADDRSTRLEN];
63c59d0c	158	strcpy (rp_str, inet_ntoa (rpg->rpf_addr.u.prefix4));
0e3b3d5d DS	159	zlog_debug ("Sending %s %sRegister Packet to %s",
0e3b3d5d DS	160	pim_str_sg_dump (&up->sg), null_register ? "NULL " : "", rp_str);
9add3b88 DS	161	}
9add3b88 DS	162
998af219	163	ifp = rpg->source_nexthop.interface;
63b8f7a3 DS	164	if (!ifp)
	165	{
	166	if (PIM_DEBUG_PIM_REG)
	167	zlog_debug ("%s: No interface to transmit register on", __PRETTY_FUNCTION__);
	168	return;
	169	}
998af219 DS	170	pinfo = (struct pim_interface *)ifp->info;
998af219 DS	171	if (!pinfo) {
63b8f7a3 DS	172	if (PIM_DEBUG_PIM_REG)
63b8f7a3 DS	173	zlog_debug("%s: Interface: %s not configured for pim to trasmit on!\n", __PRETTY_FUNCTION__, ifp->name);
998af219 DS	174	return;
	175	}
	176
19e55095	177	memset(buffer, 0, 10000);
b100a4f5	178	b1 = buffer + PIM_MSG_HEADER_LEN;
dc686f82	179	*b1 \|= null_register << 6;
998af219 DS	180	b1 = buffer + PIM_MSG_REGISTER_LEN;
998af219 DS	181
b100a4f5	182	memcpy(b1, (const unsigned char *)buf, buf_size);
998af219	183
b100a4f5	184	pim_msg_build_header(buffer, buf_size + PIM_MSG_REGISTER_LEN, PIM_MSG_TYPE_REGISTER);
998af219 DS	185
998af219 DS	186	if (pim_msg_send(pinfo->pim_sock_fd,
4df01a4e	187	src,
63c59d0c	188	rpg->rpf_addr.u.prefix4,
998af219	189	buffer,
b100a4f5	190	buf_size + PIM_MSG_REGISTER_LEN,
998af219 DS	191	ifp->name)) {
	192	if (PIM_DEBUG_PIM_TRACE) {
	193	zlog_debug("%s: could not send PIM register message on interface %s",
	194	__PRETTY_FUNCTION__, ifp->name);
	195	}
	196	return;
	197	}
	198	}
	199
01d68c9b DS	200	/*
	201	* 4.4.2 Receiving Register Messages at the RP
	202	*
	203	* When an RP receives a Register message, the course of action is
	204	* decided according to the following pseudocode:
	205	*
	206	* packet_arrives_on_rp_tunnel( pkt ) {
	207	* if( outer.dst is not one of my addresses ) {
	208	* drop the packet silently.
	209	* # Note: this may be a spoofing attempt
	210	* }
	211	* if( I_am_RP(G) AND outer.dst == RP(G) ) {
	212	* sentRegisterStop = FALSE;
	213	* if ( register.borderbit == TRUE ) {
	214	* if ( PMBR(S,G) == unknown ) {
	215	* PMBR(S,G) = outer.src
	216	* } else if ( outer.src != PMBR(S,G) ) {
	217	* send Register-Stop(S,G) to outer.src
	218	* drop the packet silently.
	219	* }
	220	* }
	221	* if ( SPTbit(S,G) OR
	222	* ( SwitchToSptDesired(S,G) AND
	223	* ( inherited_olist(S,G) == NULL ))) {
	224	* send Register-Stop(S,G) to outer.src
	225	* sentRegisterStop = TRUE;
	226	* }
	227	* if ( SPTbit(S,G) OR SwitchToSptDesired(S,G) ) {
	228	* if ( sentRegisterStop == TRUE ) {
	229	* set KeepaliveTimer(S,G) to RP_Keepalive_Period;
	230	* } else {
	231	* set KeepaliveTimer(S,G) to Keepalive_Period;
	232	* }
	233	* }
	234	* if( !SPTbit(S,G) AND ! pkt.NullRegisterBit ) {
	235	* decapsulate and forward the inner packet to
	236	* inherited_olist(S,G,rpt) # Note (+)
	237	* }
	238	* } else {
	239	* send Register-Stop(S,G) to outer.src
	240	* # Note (*)
	241	* }
	242	* }
	243	*/
	244	int
	245	pim_register_recv (struct interface *ifp,
	246	struct in_addr dest_addr,
	247	struct in_addr src_addr,
	248	uint8_t *tlv_buf, int tlv_buf_size)
	249	{
77e390e5 DS	250	int sentRegisterStop = 0;
77e390e5 DS	251	struct ip *ip_hdr;
4ed0af70	252	struct prefix_sg sg;
77e390e5	253	uint32_t *bits;
a6dc7de6	254	int i_am_rp = 0;
01d68c9b	255
75a26779 DS	256	#define PIM_MSG_REGISTER_BIT_RESERVED_LEN 4
	257	ip_hdr = (struct ip *)(tlv_buf + PIM_MSG_REGISTER_BIT_RESERVED_LEN);
	258
	259	if (!pim_rp_check_is_my_ip_address (ip_hdr->ip_dst, dest_addr)) {
d41b415c	260	if (PIM_DEBUG_PIM_REG) {
eaa54bdb	261	char dest[INET_ADDRSTRLEN];
01d68c9b DS	262
	263	pim_inet4_dump ("<dst?>", dest_addr, dest, sizeof(dest));
	264	zlog_debug ("%s: Received Register message for %s that I do not own", __func__,
	265	dest);
	266	}
	267	return 0;
	268	}
	269
77e390e5 DS	270	/*
	271	* Please note this is not drawn to get the correct bit/data size
	272	*
	273	* The entirety of the REGISTER packet looks like this:
	274	* -------------------------------------------------------------
	275	* \| Ver \| Type \| Reserved \| Checksum \|
	276	* \|-----------------------------------------------------------\|
	277	* \|B\|N\| Reserved 2 \|
	278	* \|-----------------------------------------------------------\|
	279	* \| Encap \| IP HDR \|
	280	* \| Mcast \| \|
	281	* \| Packet \|--------------------------------------------------\|
	282	* \| \| Mcast Data \|
	283	* \| \| \|
	284	* ...
	285	*
	286	* tlv_buf when received from the caller points at the B bit
	287	* We need to know the inner source and dest
	288	*/
	289	bits = (uint32_t *)tlv_buf;
83d8ff00 DS	290
	291	/*
	292	* tlv_buf points to the start of the \|B\|N\|... Reserved
	293	* Line above. So we need to add 4 bytes to get to the
	294	* start of the actual Encapsulated data.
	295	*/
4ed0af70 DS	296	memset (&sg, 0, sizeof (struct prefix_sg));
	297	sg.src = ip_hdr->ip_src;
	298	sg.grp = ip_hdr->ip_dst;
77e390e5	299
a6dc7de6	300	i_am_rp = I_am_RP (sg.grp);
5d84a3bc DS	301
	302	if (PIM_DEBUG_PIM_REG)
	303	{
	304	char src_str[INET_ADDRSTRLEN];
	305
	306	pim_inet4_dump ("<src?>", src_addr, src_str, sizeof (src_str));
	307	zlog_debug ("Received Register message(%s) from %s on %s, rp: %d",
	308	pim_str_sg_dump (&sg), src_str, ifp->name, i_am_rp);
	309	}
	310
a6dc7de6	311	if (i_am_rp && (dest_addr.s_addr == ((RP (sg.grp))->rpf_addr.u.prefix4.s_addr))) {
77e390e5	312	sentRegisterStop = 0;
01d68c9b	313
9eda95bd	314	if (*bits & PIM_REGISTER_BORDER_BIT) {
65e1fcd7	315	struct in_addr pimbr = pim_br_get_pmbr (&sg);
01d68c9b DS	316	if (PIM_DEBUG_PIM_PACKETS)
	317	zlog_debug("%s: Received Register message with Border bit set", __func__);
	318
	319	if (pimbr.s_addr == pim_br_unknown.s_addr)
65e1fcd7	320	pim_br_set_pmbr(&sg, src_addr);
80c0d168	321	else if (src_addr.s_addr != pimbr.s_addr) {
4df01a4e	322	pim_register_stop_send (ifp, &sg, dest_addr, src_addr);
01d68c9b DS	323	if (PIM_DEBUG_PIM_PACKETS)
	324	zlog_debug("%s: Sending register-Stop to %s and dropping mr. packet",
	325	__func__, "Sender");
77e390e5 DS	326	/* Drop Packet Silently */
77e390e5 DS	327	return 1;
01d68c9b DS	328	}
01d68c9b DS	329	}
77e390e5	330
5074a423	331	struct pim_upstream *upstream = pim_upstream_find (&sg);
77e390e5 DS	332	/*
	333	* If we don't have a place to send ignore the packet
	334	*/
	335	if (!upstream)
9fd309db	336	{
e5905a3b DS	337	upstream = pim_upstream_add (&sg, ifp,
	338	PIM_UPSTREAM_FLAG_MASK_SRC_STREAM,
	339	__PRETTY_FUNCTION__);
4e85d209 DS	340	if (!upstream)
4e85d209 DS	341	{
63b8f7a3	342	zlog_warn ("Failure to create upstream state");
4e85d209 DS	343	return 1;
4e85d209 DS	344	}
1bf16443	345	PIM_UPSTREAM_FLAG_SET_SRC_STREAM(upstream->flags);
5ce79466	346
8e38a2cf	347	upstream->upstream_register = src_addr;
36d6bd7d	348	pim_rp_set_upstream_addr (&upstream->upstream_addr, sg.src, sg.grp);
e5009aed DS	349	if (pim_nexthop_lookup (&upstream->rpf.source_nexthop,
	350	upstream->upstream_addr, 1) != 0)
	351	{
	352	if (PIM_DEBUG_PIM_REG)
	353	{
	354	zlog_debug ("Received Register(%s), for which I have no path back", pim_str_sg_dump (&upstream->sg));
	355	}
1bf16443	356	PIM_UPSTREAM_FLAG_UNSET_SRC_STREAM(upstream->flags);
e5009aed DS	357	pim_upstream_del (upstream, __PRETTY_FUNCTION__);
	358	return 1;
	359	}
4ed0af70	360	upstream->sg.src = sg.src;
216bb84f DS	361	upstream->rpf.rpf_addr = upstream->rpf.source_nexthop.mrib_nexthop_addr;
216bb84f DS	362
8e38a2cf	363	upstream->join_state = PIM_UPSTREAM_PRUNE;
219e0013	364
9fd309db DS	365	}
9fd309db DS	366
77e390e5	367	if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) \|\|
ad410c6c	368	((SwitchToSptDesired(&sg)) &&
4fdc8f36	369	pim_upstream_inherited_olist (upstream) == 0)) {
216bb84f	370	//pim_scan_individual_oil (upstream->channel_oil);
4df01a4e	371	pim_register_stop_send (ifp, &sg, dest_addr, src_addr);
77e390e5	372	sentRegisterStop = 1;
5d84a3bc DS	373	} else {
	374	if (PIM_DEBUG_PIM_REG)
	375	zlog_debug ("(%s) sptbit: %d", pim_str_sg_dump (&upstream->sg), upstream->sptbit);
77e390e5	376	}
77e390e5	377	if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) \|\|
ad410c6c	378	(SwitchToSptDesired(&sg))) {
80c0d168	379	if (sentRegisterStop) {
01408ede	380	pim_upstream_keep_alive_timer_start (upstream, qpim_rp_keep_alive_time);
77e390e5	381	} else {
4304f95c	382	pim_upstream_keep_alive_timer_start (upstream, qpim_keep_alive_time);
77e390e5 DS	383	}
	384	}
	385
	386	if (!(upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE) &&
2ca35b3d DS	387	!(*bits & PIM_REGISTER_NR_BIT))
2ca35b3d DS	388	{
2ca35b3d DS	389	//decapsulate and forward the iner packet to
2ca35b3d DS	390	//inherited_olist(S,G,rpt)
0365f56b	391	// This is taken care of by the kernel for us
2ca35b3d	392	}
1bf16443	393	pim_upstream_msdp_reg_timer_start(upstream);
77e390e5	394	} else {
a6dc7de6 DS	395	if (PIM_DEBUG_PIM_REG)
	396	{
	397	if (!i_am_rp)
	398	zlog_debug ("Received Register packet for %s, Rejecting packet because I am not the RP configured for group",
	399	pim_str_sg_dump (&sg));
	400	else
	401	zlog_debug ("Received Register packet for %s, Rejecting packet because the dst ip address is not the actual RP",
	402	pim_str_sg_dump (&sg));
	403	}
4df01a4e	404	pim_register_stop_send (ifp, &sg, dest_addr, src_addr);
77e390e5	405	}
01d68c9b DS	406
	407	return 1;
	408	}