[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)
{
	if (pim_is_grp_ssm(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, pimg->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(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;

	upstream = pim_upstream_find(&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, pimg->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(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(&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;
			}

			upstream->upstream_register = src_addr;
		}

		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", upstream->sg_str,
					   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 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	{
d62a17ae	51	if (pim_is_grp_ssm(up->sg.grp)) {
	52	if (PIM_DEBUG_PIM_EVENTS)
	53	zlog_debug("%s register setup skipped as group is SSM",
	54	up->sg_str);
	55	return;
	56	}
	57
43e40fdf	58	pim_channel_add_oif(up->channel_oil, pimg->regiface,
d62a17ae	59	PIM_OIF_FLAG_PROTO_PIM);
d62a17ae	60	up->reg_state = PIM_REG_JOIN;
15a5dafe	61	}
15a5dafe	62
d62a17ae	63	void pim_register_stop_send(struct interface ifp, struct prefix_sg sg,
d62a17ae	64	struct in_addr src, struct in_addr originator)
01d68c9b	65	{
d62a17ae	66	struct pim_interface *pinfo;
	67	unsigned char buffer[10000];
	68	unsigned int b1length = 0;
	69	unsigned int length;
	70	uint8_t *b1;
	71	struct prefix p;
	72
	73	if (PIM_DEBUG_PIM_REG) {
	74	zlog_debug("Sending Register stop for %s to %s on %s",
	75	pim_str_sg_dump(sg), inet_ntoa(originator),
	76	ifp->name);
	77	}
	78
	79	memset(buffer, 0, 10000);
	80	b1 = (uint8_t *)buffer + PIM_MSG_REGISTER_STOP_LEN;
	81
	82	length = pim_encode_addr_group(b1, AFI_IP, 0, 0, sg->grp);
	83	b1length += length;
	84	b1 += length;
	85
	86	p.family = AF_INET;
	87	p.u.prefix4 = sg->src;
	88	p.prefixlen = 32;
	89	length = pim_encode_addr_ucast(b1, &p);
	90	b1length += length;
	91
	92	pim_msg_build_header(buffer, b1length + PIM_MSG_REGISTER_STOP_LEN,
	93	PIM_MSG_TYPE_REG_STOP);
	94
	95	pinfo = (struct pim_interface *)ifp->info;
	96	if (!pinfo) {
	97	if (PIM_DEBUG_PIM_TRACE)
	98	zlog_debug("%s: No pinfo!\n", __PRETTY_FUNCTION__);
	99	return;
13c2408c	100	}
d62a17ae	101	if (pim_msg_send(pinfo->pim_sock_fd, src, originator, buffer,
	102	b1length + PIM_MSG_REGISTER_STOP_LEN, ifp->name)) {
	103	if (PIM_DEBUG_PIM_TRACE) {
	104	zlog_debug(
	105	"%s: could not send PIM register stop message on interface %s",
	106	__PRETTY_FUNCTION__, ifp->name);
	107	}
	108	}
	109	++pinfo->pim_ifstat_reg_stop_send;
01d68c9b DS	110	}
01d68c9b DS	111
d62a17ae	112	int pim_register_stop_recv(uint8_t *buf, int buf_size)
4dffc880	113	{
d62a17ae	114	struct pim_upstream *upstream = NULL;
	115	struct prefix source;
	116	struct prefix_sg sg;
	117	int l;
	118
	119	memset(&sg, 0, sizeof(struct prefix_sg));
	120	l = pim_parse_addr_group(&sg, buf, buf_size);
	121	buf += l;
	122	buf_size -= l;
	123	pim_parse_addr_ucast(&source, buf, buf_size);
	124	sg.src = source.u.prefix4;
	125
	126	upstream = pim_upstream_find(&sg);
	127	if (!upstream) {
	128	return 0;
	129	}
	130
	131	if (PIM_DEBUG_PIM_REG)
	132	zlog_debug("Received Register stop for %s", upstream->sg_str);
	133
	134	switch (upstream->reg_state) {
	135	case PIM_REG_NOINFO:
	136	case PIM_REG_PRUNE:
	137	return 0;
	138	break;
	139	case PIM_REG_JOIN:
	140	upstream->reg_state = PIM_REG_PRUNE;
43e40fdf	141	pim_channel_del_oif(upstream->channel_oil, pimg->regiface,
d62a17ae	142	PIM_OIF_FLAG_PROTO_PIM);
	143	pim_upstream_start_register_stop_timer(upstream, 0);
	144	break;
	145	case PIM_REG_JOIN_PENDING:
	146	upstream->reg_state = PIM_REG_PRUNE;
	147	pim_upstream_start_register_stop_timer(upstream, 0);
	148	return 0;
	149	break;
	150	}
	151
	152	return 0;
4dffc880 DS	153	}
4dffc880 DS	154
d62a17ae	155	void pim_register_send(const uint8_t *buf, int buf_size, struct in_addr src,
	156	struct pim_rpf *rpg, int null_register,
	157	struct pim_upstream *up)
998af219	158	{
d62a17ae	159	unsigned char buffer[10000];
	160	unsigned char *b1;
	161	struct pim_interface *pinfo;
	162	struct interface *ifp;
	163
	164	if (PIM_DEBUG_PIM_REG) {
	165	zlog_debug("Sending %s %sRegister Packet to %s", up->sg_str,
	166	null_register ? "NULL " : "",
	167	inet_ntoa(rpg->rpf_addr.u.prefix4));
	168	}
	169
	170	ifp = rpg->source_nexthop.interface;
	171	if (!ifp) {
	172	if (PIM_DEBUG_PIM_REG)
	173	zlog_debug("%s: No interface to transmit register on",
	174	__PRETTY_FUNCTION__);
	175	return;
	176	}
	177	pinfo = (struct pim_interface *)ifp->info;
	178	if (!pinfo) {
	179	if (PIM_DEBUG_PIM_REG)
	180	zlog_debug(
	181	"%s: Interface: %s not configured for pim to trasmit on!\n",
	182	__PRETTY_FUNCTION__, ifp->name);
	183	return;
	184	}
	185
	186	if (PIM_DEBUG_PIM_REG) {
	187	char rp_str[INET_ADDRSTRLEN];
	188	strncpy(rp_str, inet_ntoa(rpg->rpf_addr.u.prefix4),
	189	INET_ADDRSTRLEN - 1);
	190	zlog_debug("%s: Sending %s %sRegister Packet to %s on %s",
	191	__PRETTY_FUNCTION__, up->sg_str,
	192	null_register ? "NULL " : "", rp_str, ifp->name);
	193	}
	194
	195	memset(buffer, 0, 10000);
	196	b1 = buffer + PIM_MSG_HEADER_LEN;
	197	*b1 \|= null_register << 6;
	198	b1 = buffer + PIM_MSG_REGISTER_LEN;
	199
	200	memcpy(b1, (const unsigned char *)buf, buf_size);
	201
	202	pim_msg_build_header(buffer, buf_size + PIM_MSG_REGISTER_LEN,
	203	PIM_MSG_TYPE_REGISTER);
	204
	205	++pinfo->pim_ifstat_reg_send;
	206
	207	if (pim_msg_send(pinfo->pim_sock_fd, src, rpg->rpf_addr.u.prefix4,
	208	buffer, buf_size + PIM_MSG_REGISTER_LEN, ifp->name)) {
	209	if (PIM_DEBUG_PIM_TRACE) {
	210	zlog_debug(
	211	"%s: could not send PIM register message on interface %s",
	212	__PRETTY_FUNCTION__, ifp->name);
	213	}
	214	return;
	215	}
998af219 DS	216	}
998af219 DS	217
01d68c9b DS	218	/*
	219	* 4.4.2 Receiving Register Messages at the RP
	220	*
	221	* When an RP receives a Register message, the course of action is
	222	* decided according to the following pseudocode:
	223	*
	224	* packet_arrives_on_rp_tunnel( pkt ) {
	225	* if( outer.dst is not one of my addresses ) {
	226	* drop the packet silently.
	227	* # Note: this may be a spoofing attempt
	228	* }
	229	* if( I_am_RP(G) AND outer.dst == RP(G) ) {
	230	* sentRegisterStop = FALSE;
	231	* if ( register.borderbit == TRUE ) {
	232	* if ( PMBR(S,G) == unknown ) {
	233	* PMBR(S,G) = outer.src
	234	* } else if ( outer.src != PMBR(S,G) ) {
	235	* send Register-Stop(S,G) to outer.src
	236	* drop the packet silently.
	237	* }
	238	* }
	239	* if ( SPTbit(S,G) OR
	240	* ( SwitchToSptDesired(S,G) AND
	241	* ( inherited_olist(S,G) == NULL ))) {
	242	* send Register-Stop(S,G) to outer.src
	243	* sentRegisterStop = TRUE;
	244	* }
	245	* if ( SPTbit(S,G) OR SwitchToSptDesired(S,G) ) {
	246	* if ( sentRegisterStop == TRUE ) {
	247	* set KeepaliveTimer(S,G) to RP_Keepalive_Period;
	248	* } else {
	249	* set KeepaliveTimer(S,G) to Keepalive_Period;
	250	* }
	251	* }
	252	* if( !SPTbit(S,G) AND ! pkt.NullRegisterBit ) {
	253	* decapsulate and forward the inner packet to
	254	* inherited_olist(S,G,rpt) # Note (+)
	255	* }
	256	* } else {
	257	* send Register-Stop(S,G) to outer.src
	258	* # Note (*)
	259	* }
	260	* }
	261	*/
d62a17ae	262	int pim_register_recv(struct interface *ifp, struct in_addr dest_addr,
	263	struct in_addr src_addr, uint8_t *tlv_buf,
	264	int tlv_buf_size)
01d68c9b	265	{
d62a17ae	266	int sentRegisterStop = 0;
	267	struct ip *ip_hdr;
	268	struct prefix_sg sg;
	269	uint32_t *bits;
	270	int i_am_rp = 0;
	271	struct pim_interface *pim_ifp = NULL;
01d68c9b	272
fec883d9 DS	273	pim_ifp = ifp->info;
fec883d9 DS	274
75a26779	275	#define PIM_MSG_REGISTER_BIT_RESERVED_LEN 4
d62a17ae	276	ip_hdr = (struct ip *)(tlv_buf + PIM_MSG_REGISTER_BIT_RESERVED_LEN);
d62a17ae	277
fec883d9 DS	278	if (!pim_rp_check_is_my_ip_address(pim_ifp->pim, ip_hdr->ip_dst,
fec883d9 DS	279	dest_addr)) {
d62a17ae	280	if (PIM_DEBUG_PIM_REG) {
	281	char dest[INET_ADDRSTRLEN];
	282
	283	pim_inet4_dump("<dst?>", dest_addr, dest, sizeof(dest));
	284	zlog_debug(
	285	"%s: Received Register message for %s that I do not own",
	286	__func__, dest);
	287	}
	288	return 0;
	289	}
	290
d62a17ae	291	++pim_ifp->pim_ifstat_reg_recv;
	292
	293	/*
	294	* Please note this is not drawn to get the correct bit/data size
	295	*
	296	* The entirety of the REGISTER packet looks like this:
	297	* -------------------------------------------------------------
	298	* \| Ver \| Type \| Reserved \| Checksum \|
	299	* \|-----------------------------------------------------------\|
	300	* \|B\|N\| Reserved 2 \|
	301	* \|-----------------------------------------------------------\|
	302	* \| Encap \| IP HDR \|
	303	* \| Mcast \| \|
	304	* \| Packet \|--------------------------------------------------\|
	305	* \| \| Mcast Data \|
	306	* \| \| \|
	307	* ...
	308	*
	309	* tlv_buf when received from the caller points at the B bit
	310	* We need to know the inner source and dest
	311	*/
	312	bits = (uint32_t *)tlv_buf;
	313
	314	/*
	315	* tlv_buf points to the start of the \|B\|N\|... Reserved
	316	* Line above. So we need to add 4 bytes to get to the
	317	* start of the actual Encapsulated data.
	318	*/
	319	memset(&sg, 0, sizeof(struct prefix_sg));
	320	sg.src = ip_hdr->ip_src;
	321	sg.grp = ip_hdr->ip_dst;
	322
	323	i_am_rp = I_am_RP(sg.grp);
	324
	325	if (PIM_DEBUG_PIM_REG) {
	326	char src_str[INET_ADDRSTRLEN];
	327
	328	pim_inet4_dump("<src?>", src_addr, src_str, sizeof(src_str));
	329	zlog_debug(
	330	"Received Register message(%s) from %s on %s, rp: %d",
	331	pim_str_sg_dump(&sg), src_str, ifp->name, i_am_rp);
	332	}
	333
fec883d9 DS	334	if (i_am_rp
	335	&& (dest_addr.s_addr
	336	== ((RP(pim_ifp->pim, sg.grp))->rpf_addr.u.prefix4.s_addr))) {
d62a17ae	337	sentRegisterStop = 0;
	338
	339	if (*bits & PIM_REGISTER_BORDER_BIT) {
	340	struct in_addr pimbr = pim_br_get_pmbr(&sg);
	341	if (PIM_DEBUG_PIM_PACKETS)
	342	zlog_debug(
	343	"%s: Received Register message with Border bit set",
	344	__func__);
	345
	346	if (pimbr.s_addr == pim_br_unknown.s_addr)
	347	pim_br_set_pmbr(&sg, src_addr);
	348	else if (src_addr.s_addr != pimbr.s_addr) {
	349	pim_register_stop_send(ifp, &sg, dest_addr,
	350	src_addr);
	351	if (PIM_DEBUG_PIM_PACKETS)
	352	zlog_debug(
	353	"%s: Sending register-Stop to %s and dropping mr. packet",
	354	__func__, "Sender");
	355	/* Drop Packet Silently */
	356	return 0;
	357	}
	358	}
	359
	360	struct pim_upstream *upstream = pim_upstream_find(&sg);
	361	/*
	362	* If we don't have a place to send ignore the packet
	363	*/
	364	if (!upstream) {
	365	upstream = pim_upstream_add(
	366	&sg, ifp, PIM_UPSTREAM_FLAG_MASK_SRC_STREAM,
	367	__PRETTY_FUNCTION__);
	368	if (!upstream) {
	369	zlog_warn("Failure to create upstream state");
	370	return 1;
	371	}
	372
	373	upstream->upstream_register = src_addr;
	374	}
	375
	376	if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
	377	\|\| ((SwitchToSptDesired(&sg))
	378	&& pim_upstream_inherited_olist(upstream) == 0)) {
	379	// pim_scan_individual_oil (upstream->channel_oil);
	380	pim_register_stop_send(ifp, &sg, dest_addr, src_addr);
	381	sentRegisterStop = 1;
	382	} else {
	383	if (PIM_DEBUG_PIM_REG)
	384	zlog_debug("(%s) sptbit: %d", upstream->sg_str,
	385	upstream->sptbit);
	386	}
	387	if ((upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
	388	\|\| (SwitchToSptDesired(&sg))) {
	389	if (sentRegisterStop) {
	390	pim_upstream_keep_alive_timer_start(
	391	upstream, qpim_rp_keep_alive_time);
	392	} else {
	393	pim_upstream_keep_alive_timer_start(
	394	upstream, qpim_keep_alive_time);
	395	}
	396	}
	397
	398	if (!(upstream->sptbit == PIM_UPSTREAM_SPTBIT_TRUE)
	399	&& !(*bits & PIM_REGISTER_NR_BIT)) {
	400	// decapsulate and forward the iner packet to
401	// inherited_olist(S,G,rpt)
402	// This is taken care of by the kernel for us
403	}
404	pim_upstream_msdp_reg_timer_start(upstream);
405	} else {
406	if (PIM_DEBUG_PIM_REG) {
407	if (!i_am_rp)
408	zlog_debug(
409	"Received Register packet for %s, Rejecting packet because I am not the RP configured for group",
410	pim_str_sg_dump(&sg));
411	else
412	zlog_debug(
413	"Received Register packet for %s, Rejecting packet because the dst ip address is not the actual RP",
414	pim_str_sg_dump(&sg));
415	}
416	pim_register_stop_send(ifp, &sg, dest_addr, src_addr);
417	}
418
8dc60b69	419	return 0;
01d68c9b	420	}