[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"
#include "pim_ssm.h"

struct thread *send_test_packet_timer = NULL;

void pim_register_join(struct pim_upstream *up)
{
	struct pim_instance *pim = up->channel_oil->pim;

	if (pim_is_grp_ssm(pim, up->sg.grp)) {
		if (PIM_DEBUG_PIM_EVENTS)
			zlog_debug("%s register setup skipped as group is SSM",
				   up->sg_str);
		return;
	}

	pim_channel_add_oif(up->channel_oil, pim->regiface,
			    PIM_OIF_FLAG_PROTO_PIM);
	up->reg_state = PIM_REG_JOIN;
}

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);
		}
	}
	++pinfo->pim_ifstat_reg_stop_send;
}

int pim_register_stop_recv(struct interface *ifp, uint8_t *buf, int buf_size)
{
	struct pim_interface *pim_ifp = ifp->info;
	struct pim_instance *pim = pim_ifp->pim;
	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;

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

	if (PIM_DEBUG_PIM_REG)
		zlog_debug("Received Register stop for %s", upstream->sg_str);

	switch (upstream->reg_state) {
	case PIM_REG_NOINFO:
	case PIM_REG_PRUNE:
		return 0;
		break;
	case PIM_REG_JOIN:
		upstream->reg_state = PIM_REG_PRUNE;
		pim_channel_del_oif(upstream->channel_oil, pim->regiface,
				    PIM_OIF_FLAG_PROTO_PIM);
		pim_upstream_start_register_stop_timer(upstream, 0);
		break;
	case PIM_REG_JOIN_PENDING:
		upstream->reg_state = PIM_REG_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) {
		zlog_debug("Sending %s %sRegister Packet to %s", up->sg_str,
			   null_register ? "NULL " : "",
			   inet_ntoa(rpg->rpf_addr.u.prefix4));
	}

	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;
	}

	if (PIM_DEBUG_PIM_REG) {
		char rp_str[INET_ADDRSTRLEN];
		strncpy(rp_str, inet_ntoa(rpg->rpf_addr.u.prefix4),
			INET_ADDRSTRLEN - 1);
		zlog_debug("%s: Sending %s %sRegister Packet to %s on %s",
			   __PRETTY_FUNCTION__, up->sg_str,
			   null_register ? "NULL " : "", rp_str, ifp->name);
	}

	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);

	++pinfo->pim_ifstat_reg_send;

	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;
	struct pim_interface *pim_ifp = NULL;

	pim_ifp = ifp->info;

#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(pim_ifp->pim, 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;
	}

	++pim_ifp->pim_ifstat_reg_recv;

	/*
	 * 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(pim_ifp->pim, 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(pim_ifp->pim, 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 0;
			}
		}

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

			upstream->upstream_register = src_addr;
		} else {
			/*
			 * If the FHR has set a very very fast register timer
			 * there exists a possibility that the incoming NULL
			 * register
			 * is happening before we set the spt bit.  If so
			 * Do a quick check to update the counters and
			 * then set the spt bit as appropriate
			 */
			if (upstream->sptbit != PIM_UPSTREAM_SPTBIT_TRUE) {
				pim_mroute_update_counters(
					upstream->channel_oil);
				/*
				 * Have we seen packets?
				 */
				if (upstream->channel_oil->cc.oldpktcnt
				    < upstream->channel_oil->cc.pktcnt)
					pim_upstream_set_sptbit(
						upstream,
						upstream->rpf.source_nexthop
							.interface);
			}
		}

		if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
		    || ((SwitchToSptDesired(pim_ifp->pim, &sg))
			&& pim_upstream_inherited_olist(pim_ifp->pim, 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", upstream->sg_str,
					   upstream->sptbit);
		}
		if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
		    || (SwitchToSptDesired(pim_ifp->pim, &sg))) {
			if (sentRegisterStop) {
				pim_upstream_keep_alive_timer_start(
					upstream,
					pim_ifp->pim->rp_keep_alive_time);
			} else {
				pim_upstream_keep_alive_timer_start(
					upstream,
					pim_ifp->pim->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 0;
}
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	*
896014f4 DL	16	* You should have received a copy of the GNU General Public License along
	17	* with this program; see the file COPYING; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
01d68c9b DS	19	*/
	20
	21	#include <zebra.h>
	22
	23	#include "log.h"
	24	#include "if.h"
	25	#include "thread.h"
13c2408c	26	#include "prefix.h"
dfe43e25 DW	27	#include "vty.h"
dfe43e25 DW	28	#include "plist.h"
01d68c9b DS	29
01d68c9b DS	30	#include "pimd.h"
998af219 DS	31	#include "pim_mroute.h"
	32	#include "pim_iface.h"
	33	#include "pim_msg.h"
	34	#include "pim_pim.h"
01d68c9b DS	35	#include "pim_str.h"
	36	#include "pim_rp.h"
	37	#include "pim_register.h"
80c0d168	38	#include "pim_upstream.h"
01d68c9b	39	#include "pim_br.h"
2ca35b3d DS	40	#include "pim_rpf.h"
	41	#include "pim_oil.h"
	42	#include "pim_zebra.h"
	43	#include "pim_join.h"
13c2408c	44	#include "pim_util.h"
15a5dafe	45	#include "pim_ssm.h"
01d68c9b DS	46
	47	struct thread *send_test_packet_timer = NULL;
	48
d62a17ae	49	void pim_register_join(struct pim_upstream *up)
15a5dafe	50	{
ac7eaeb4 DS	51	struct pim_instance *pim = up->channel_oil->pim;
ac7eaeb4 DS	52
6f439a70	53	if (pim_is_grp_ssm(pim, up->sg.grp)) {
d62a17ae	54	if (PIM_DEBUG_PIM_EVENTS)
	55	zlog_debug("%s register setup skipped as group is SSM",
	56	up->sg_str);
	57	return;
	58	}
	59
ac7eaeb4	60	pim_channel_add_oif(up->channel_oil, pim->regiface,
d62a17ae	61	PIM_OIF_FLAG_PROTO_PIM);
d62a17ae	62	up->reg_state = PIM_REG_JOIN;
15a5dafe	63	}
15a5dafe	64
d62a17ae	65	void pim_register_stop_send(struct interface ifp, struct prefix_sg sg,
d62a17ae	66	struct in_addr src, struct in_addr originator)
01d68c9b	67	{
d62a17ae	68	struct pim_interface *pinfo;
	69	unsigned char buffer[10000];
	70	unsigned int b1length = 0;
	71	unsigned int length;
	72	uint8_t *b1;
	73	struct prefix p;
	74
	75	if (PIM_DEBUG_PIM_REG) {
	76	zlog_debug("Sending Register stop for %s to %s on %s",
	77	pim_str_sg_dump(sg), inet_ntoa(originator),
	78	ifp->name);
	79	}
	80
	81	memset(buffer, 0, 10000);
	82	b1 = (uint8_t *)buffer + PIM_MSG_REGISTER_STOP_LEN;
	83
	84	length = pim_encode_addr_group(b1, AFI_IP, 0, 0, sg->grp);
	85	b1length += length;
	86	b1 += length;
	87
	88	p.family = AF_INET;
	89	p.u.prefix4 = sg->src;
	90	p.prefixlen = 32;
	91	length = pim_encode_addr_ucast(b1, &p);
	92	b1length += length;
	93
	94	pim_msg_build_header(buffer, b1length + PIM_MSG_REGISTER_STOP_LEN,
	95	PIM_MSG_TYPE_REG_STOP);
	96
	97	pinfo = (struct pim_interface *)ifp->info;
	98	if (!pinfo) {
	99	if (PIM_DEBUG_PIM_TRACE)
	100	zlog_debug("%s: No pinfo!\n", __PRETTY_FUNCTION__);
	101	return;
13c2408c	102	}
d62a17ae	103	if (pim_msg_send(pinfo->pim_sock_fd, src, originator, buffer,
	104	b1length + PIM_MSG_REGISTER_STOP_LEN, ifp->name)) {
	105	if (PIM_DEBUG_PIM_TRACE) {
	106	zlog_debug(
	107	"%s: could not send PIM register stop message on interface %s",
	108	__PRETTY_FUNCTION__, ifp->name);
	109	}
	110	}
	111	++pinfo->pim_ifstat_reg_stop_send;
01d68c9b DS	112	}
01d68c9b DS	113
b206566b	114	int pim_register_stop_recv(struct interface ifp, uint8_t buf, int buf_size)
4dffc880	115	{
b206566b DS	116	struct pim_interface *pim_ifp = ifp->info;
b206566b DS	117	struct pim_instance *pim = pim_ifp->pim;
d62a17ae	118	struct pim_upstream *upstream = NULL;
	119	struct prefix source;
	120	struct prefix_sg sg;
	121	int l;
	122
	123	memset(&sg, 0, sizeof(struct prefix_sg));
	124	l = pim_parse_addr_group(&sg, buf, buf_size);
	125	buf += l;
	126	buf_size -= l;
	127	pim_parse_addr_ucast(&source, buf, buf_size);
	128	sg.src = source.u.prefix4;
	129
b206566b	130	upstream = pim_upstream_find(pim, &sg);
d62a17ae	131	if (!upstream) {
	132	return 0;
	133	}
	134
	135	if (PIM_DEBUG_PIM_REG)
	136	zlog_debug("Received Register stop for %s", upstream->sg_str);
	137
	138	switch (upstream->reg_state) {
	139	case PIM_REG_NOINFO:
	140	case PIM_REG_PRUNE:
	141	return 0;
	142	break;
	143	case PIM_REG_JOIN:
	144	upstream->reg_state = PIM_REG_PRUNE;
b206566b	145	pim_channel_del_oif(upstream->channel_oil, pim->regiface,
d62a17ae	146	PIM_OIF_FLAG_PROTO_PIM);
	147	pim_upstream_start_register_stop_timer(upstream, 0);
	148	break;
	149	case PIM_REG_JOIN_PENDING:
	150	upstream->reg_state = PIM_REG_PRUNE;
	151	pim_upstream_start_register_stop_timer(upstream, 0);
	152	return 0;
	153	break;
	154	}
	155
	156	return 0;
4dffc880 DS	157	}
4dffc880 DS	158
d62a17ae	159	void pim_register_send(const uint8_t *buf, int buf_size, struct in_addr src,
	160	struct pim_rpf *rpg, int null_register,
	161	struct pim_upstream *up)
998af219	162	{
d62a17ae	163	unsigned char buffer[10000];
	164	unsigned char *b1;
	165	struct pim_interface *pinfo;
	166	struct interface *ifp;
	167
	168	if (PIM_DEBUG_PIM_REG) {
	169	zlog_debug("Sending %s %sRegister Packet to %s", up->sg_str,
	170	null_register ? "NULL " : "",
	171	inet_ntoa(rpg->rpf_addr.u.prefix4));
	172	}
	173
	174	ifp = rpg->source_nexthop.interface;
	175	if (!ifp) {
	176	if (PIM_DEBUG_PIM_REG)
	177	zlog_debug("%s: No interface to transmit register on",
	178	__PRETTY_FUNCTION__);
	179	return;
	180	}
	181	pinfo = (struct pim_interface *)ifp->info;
	182	if (!pinfo) {
	183	if (PIM_DEBUG_PIM_REG)
	184	zlog_debug(
	185	"%s: Interface: %s not configured for pim to trasmit on!\n",
	186	__PRETTY_FUNCTION__, ifp->name);
	187	return;
	188	}
	189
	190	if (PIM_DEBUG_PIM_REG) {
	191	char rp_str[INET_ADDRSTRLEN];
	192	strncpy(rp_str, inet_ntoa(rpg->rpf_addr.u.prefix4),
	193	INET_ADDRSTRLEN - 1);
	194	zlog_debug("%s: Sending %s %sRegister Packet to %s on %s",
	195	__PRETTY_FUNCTION__, up->sg_str,
	196	null_register ? "NULL " : "", rp_str, ifp->name);
	197	}
	198
	199	memset(buffer, 0, 10000);
	200	b1 = buffer + PIM_MSG_HEADER_LEN;
	201	*b1 \|= null_register << 6;
	202	b1 = buffer + PIM_MSG_REGISTER_LEN;
	203
	204	memcpy(b1, (const unsigned char *)buf, buf_size);
	205
	206	pim_msg_build_header(buffer, buf_size + PIM_MSG_REGISTER_LEN,
	207	PIM_MSG_TYPE_REGISTER);
	208
	209	++pinfo->pim_ifstat_reg_send;
	210
	211	if (pim_msg_send(pinfo->pim_sock_fd, src, rpg->rpf_addr.u.prefix4,
	212	buffer, buf_size + PIM_MSG_REGISTER_LEN, ifp->name)) {
	213	if (PIM_DEBUG_PIM_TRACE) {
	214	zlog_debug(
	215	"%s: could not send PIM register message on interface %s",
	216	__PRETTY_FUNCTION__, ifp->name);
	217	}
	218	return;
	219	}
998af219 DS	220	}
998af219 DS	221
01d68c9b DS	222	/*
	223	* 4.4.2 Receiving Register Messages at the RP
	224	*
	225	* When an RP receives a Register message, the course of action is
	226	* decided according to the following pseudocode:
	227	*
	228	* packet_arrives_on_rp_tunnel( pkt ) {
	229	* if( outer.dst is not one of my addresses ) {
	230	* drop the packet silently.
	231	* # Note: this may be a spoofing attempt
	232	* }
	233	* if( I_am_RP(G) AND outer.dst == RP(G) ) {
	234	* sentRegisterStop = FALSE;
	235	* if ( register.borderbit == TRUE ) {
	236	* if ( PMBR(S,G) == unknown ) {
	237	* PMBR(S,G) = outer.src
	238	* } else if ( outer.src != PMBR(S,G) ) {
	239	* send Register-Stop(S,G) to outer.src
	240	* drop the packet silently.
	241	* }
	242	* }
	243	* if ( SPTbit(S,G) OR
	244	* ( SwitchToSptDesired(S,G) AND
	245	* ( inherited_olist(S,G) == NULL ))) {
	246	* send Register-Stop(S,G) to outer.src
	247	* sentRegisterStop = TRUE;
	248	* }
	249	* if ( SPTbit(S,G) OR SwitchToSptDesired(S,G) ) {
	250	* if ( sentRegisterStop == TRUE ) {
	251	* set KeepaliveTimer(S,G) to RP_Keepalive_Period;
	252	* } else {
	253	* set KeepaliveTimer(S,G) to Keepalive_Period;
	254	* }
	255	* }
	256	* if( !SPTbit(S,G) AND ! pkt.NullRegisterBit ) {
	257	* decapsulate and forward the inner packet to
	258	* inherited_olist(S,G,rpt) # Note (+)
	259	* }
	260	* } else {
	261	* send Register-Stop(S,G) to outer.src
	262	* # Note (*)
	263	* }
	264	* }
	265	*/
d62a17ae	266	int pim_register_recv(struct interface *ifp, struct in_addr dest_addr,
	267	struct in_addr src_addr, uint8_t *tlv_buf,
	268	int tlv_buf_size)
01d68c9b	269	{
d62a17ae	270	int sentRegisterStop = 0;
	271	struct ip *ip_hdr;
	272	struct prefix_sg sg;
	273	uint32_t *bits;
	274	int i_am_rp = 0;
	275	struct pim_interface *pim_ifp = NULL;
01d68c9b	276
fec883d9 DS	277	pim_ifp = ifp->info;
fec883d9 DS	278
75a26779	279	#define PIM_MSG_REGISTER_BIT_RESERVED_LEN 4
d62a17ae	280	ip_hdr = (struct ip *)(tlv_buf + PIM_MSG_REGISTER_BIT_RESERVED_LEN);
d62a17ae	281
fec883d9 DS	282	if (!pim_rp_check_is_my_ip_address(pim_ifp->pim, ip_hdr->ip_dst,
fec883d9 DS	283	dest_addr)) {
d62a17ae	284	if (PIM_DEBUG_PIM_REG) {
	285	char dest[INET_ADDRSTRLEN];
	286
	287	pim_inet4_dump("<dst?>", dest_addr, dest, sizeof(dest));
	288	zlog_debug(
	289	"%s: Received Register message for %s that I do not own",
	290	__func__, dest);
	291	}
	292	return 0;
	293	}
	294
d62a17ae	295	++pim_ifp->pim_ifstat_reg_recv;
	296
	297	/*
	298	* Please note this is not drawn to get the correct bit/data size
	299	*
	300	* The entirety of the REGISTER packet looks like this:
	301	* -------------------------------------------------------------
	302	* \| Ver \| Type \| Reserved \| Checksum \|
	303	* \|-----------------------------------------------------------\|
	304	* \|B\|N\| Reserved 2 \|
	305	* \|-----------------------------------------------------------\|
	306	* \| Encap \| IP HDR \|
	307	* \| Mcast \| \|
	308	* \| Packet \|--------------------------------------------------\|
	309	* \| \| Mcast Data \|
	310	* \| \| \|
	311	* ...
	312	*
	313	* tlv_buf when received from the caller points at the B bit
	314	* We need to know the inner source and dest
	315	*/
	316	bits = (uint32_t *)tlv_buf;
	317
	318	/*
	319	* tlv_buf points to the start of the \|B\|N\|... Reserved
	320	* Line above. So we need to add 4 bytes to get to the
	321	* start of the actual Encapsulated data.
	322	*/
	323	memset(&sg, 0, sizeof(struct prefix_sg));
	324	sg.src = ip_hdr->ip_src;
	325	sg.grp = ip_hdr->ip_dst;
	326
d9c9a9ee	327	i_am_rp = I_am_RP(pim_ifp->pim, sg.grp);
d62a17ae	328
	329	if (PIM_DEBUG_PIM_REG) {
	330	char src_str[INET_ADDRSTRLEN];
	331
	332	pim_inet4_dump("<src?>", src_addr, src_str, sizeof(src_str));
	333	zlog_debug(
	334	"Received Register message(%s) from %s on %s, rp: %d",
	335	pim_str_sg_dump(&sg), src_str, ifp->name, i_am_rp);
	336	}
	337
fec883d9 DS	338	if (i_am_rp
	339	&& (dest_addr.s_addr
	340	== ((RP(pim_ifp->pim, sg.grp))->rpf_addr.u.prefix4.s_addr))) {
d62a17ae	341	sentRegisterStop = 0;
	342
	343	if (*bits & PIM_REGISTER_BORDER_BIT) {
	344	struct in_addr pimbr = pim_br_get_pmbr(&sg);
	345	if (PIM_DEBUG_PIM_PACKETS)
	346	zlog_debug(
	347	"%s: Received Register message with Border bit set",
	348	__func__);
	349
	350	if (pimbr.s_addr == pim_br_unknown.s_addr)
	351	pim_br_set_pmbr(&sg, src_addr);
	352	else if (src_addr.s_addr != pimbr.s_addr) {
	353	pim_register_stop_send(ifp, &sg, dest_addr,
	354	src_addr);
	355	if (PIM_DEBUG_PIM_PACKETS)
	356	zlog_debug(
	357	"%s: Sending register-Stop to %s and dropping mr. packet",
	358	__func__, "Sender");
	359	/* Drop Packet Silently */
	360	return 0;
	361	}
	362	}
	363
9b29ea95 DS	364	struct pim_upstream *upstream =
9b29ea95 DS	365	pim_upstream_find(pim_ifp->pim, &sg);
d62a17ae	366	/*
	367	* If we don't have a place to send ignore the packet
	368	*/
	369	if (!upstream) {
	370	upstream = pim_upstream_add(
2002dcdb DS	371	pim_ifp->pim, &sg, ifp,
2002dcdb DS	372	PIM_UPSTREAM_FLAG_MASK_SRC_STREAM,
0885a9f1	373	__PRETTY_FUNCTION__, NULL);
d62a17ae	374	if (!upstream) {
	375	zlog_warn("Failure to create upstream state");
	376	return 1;
	377	}
	378
	379	upstream->upstream_register = src_addr;
cc61055f DS	380	} else {
	381	/*
	382	* If the FHR has set a very very fast register timer
	383	* there exists a possibility that the incoming NULL
	384	* register
	385	* is happening before we set the spt bit. If so
	386	* Do a quick check to update the counters and
	387	* then set the spt bit as appropriate
	388	*/
	389	if (upstream->sptbit != PIM_UPSTREAM_SPTBIT_TRUE) {
	390	pim_mroute_update_counters(
	391	upstream->channel_oil);
	392	/*
	393	* Have we seen packets?
	394	*/
	395	if (upstream->channel_oil->cc.oldpktcnt
	396	< upstream->channel_oil->cc.pktcnt)
	397	pim_upstream_set_sptbit(
	398	upstream,
	399	upstream->rpf.source_nexthop
	400	.interface);
	401	}
d62a17ae	402	}
	403
	404	if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
8e5f97e3	405	\|\| ((SwitchToSptDesired(pim_ifp->pim, &sg))
9b29ea95 DS	406	&& pim_upstream_inherited_olist(pim_ifp->pim, upstream)
9b29ea95 DS	407	== 0)) {
d62a17ae	408	// pim_scan_individual_oil (upstream->channel_oil);
	409	pim_register_stop_send(ifp, &sg, dest_addr, src_addr);
	410	sentRegisterStop = 1;
	411	} else {
	412	if (PIM_DEBUG_PIM_REG)
	413	zlog_debug("(%s) sptbit: %d", upstream->sg_str,
	414	upstream->sptbit);
	415	}
	416	if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
8e5f97e3	417	\|\| (SwitchToSptDesired(pim_ifp->pim, &sg))) {
d62a17ae	418	if (sentRegisterStop) {
d62a17ae	419	pim_upstream_keep_alive_timer_start(
996c9314 LB	420	upstream,
996c9314 LB	421	pim_ifp->pim->rp_keep_alive_time);
d62a17ae	422	} else {
d62a17ae	423	pim_upstream_keep_alive_timer_start(
996c9314 LB	424	upstream,
996c9314 LB	425	pim_ifp->pim->keep_alive_time);
d62a17ae	426	}
	427	}
	428
	429	if (!(upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
	430	&& !(*bits & PIM_REGISTER_NR_BIT)) {
	431	// decapsulate and forward the iner packet to
	432	// inherited_olist(S,G,rpt)
	433	// This is taken care of by the kernel for us
	434	}
	435	pim_upstream_msdp_reg_timer_start(upstream);
	436	} else {
	437	if (PIM_DEBUG_PIM_REG) {
	438	if (!i_am_rp)
	439	zlog_debug(
	440	"Received Register packet for %s, Rejecting packet because I am not the RP configured for group",
	441	pim_str_sg_dump(&sg));
	442	else
	443	zlog_debug(
	444	"Received Register packet for %s, Rejecting packet because the dst ip address is not the actual RP",
	445	pim_str_sg_dump(&sg));
	446	}
	447	pim_register_stop_send(ifp, &sg, dest_addr, src_addr);
	448	}
	449
8dc60b69	450	return 0;
01d68c9b	451	}