[mirror_frr.git] / isisd / isis_pfpacket.c

/*
 * IS-IS Rout(e)ing protocol - isis_pfpacket.c
 *
 * Copyright (C) 2001,2002    Sampo Saaristo
 *                            Tampere University of Technology
 *                            Institute of Communications Engineering
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public Licenseas 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>
#if ISIS_METHOD == ISIS_METHOD_PFPACKET
#include <net/ethernet.h> /* the L2 protocols */
#include <netpacket/packet.h>

#include <linux/filter.h>

#include "log.h"
#include "network.h"
#include "stream.h"
#include "if.h"
#include "lib_errors.h"
#include "vrf.h"

#include "isisd/isis_constants.h"
#include "isisd/isis_common.h"
#include "isisd/isis_circuit.h"
#include "isisd/isis_flags.h"
#include "isisd/isisd.h"
#include "isisd/isis_constants.h"
#include "isisd/isis_circuit.h"
#include "isisd/isis_network.h"

#include "privs.h"

/* tcpdump -i eth0 'isis' -dd */
static const struct sock_filter isisfilter[] = {
	/* NB: we're in SOCK_DGRAM, so src/dst mac + length are stripped
	 * off!
	 * (OTOH it's a bit more lower-layer agnostic and might work
	 * over GRE?) */
	/*	{ 0x28, 0, 0, 0x0000000c - 14 }, */
	/*	{ 0x25, 5, 0, 0x000005dc }, */
	{0x28, 0, 0, 0x0000000e - 14}, {0x15, 0, 3, 0x0000fefe},
	{0x30, 0, 0, 0x00000011 - 14}, {0x15, 0, 1, 0x00000083},
	{0x6, 0, 0, 0x00040000},       {0x6, 0, 0, 0x00000000},
};

static const struct sock_fprog bpf = {
	.len = array_size(isisfilter),
	.filter = (struct sock_filter *)isisfilter,
};

/*
 * Table 9 - Architectural constants for use with ISO 8802 subnetworks
 * ISO 10589 - 8.4.8
 */

static const uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
static const uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
static const uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
static const uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};

static uint8_t discard_buff[8192];

/*
 * if level is 0 we are joining p2p multicast
 * FIXME: and the p2p multicast being ???
 */
static int isis_multicast_join(int fd, int registerto, int if_num)
{
	struct packet_mreq mreq;

	memset(&mreq, 0, sizeof(mreq));
	mreq.mr_ifindex = if_num;
	if (registerto) {
		mreq.mr_type = PACKET_MR_MULTICAST;
		mreq.mr_alen = ETH_ALEN;
		if (registerto == 1)
			memcpy(&mreq.mr_address, ALL_L1_ISS, ETH_ALEN);
		else if (registerto == 2)
			memcpy(&mreq.mr_address, ALL_L2_ISS, ETH_ALEN);
		else if (registerto == 3)
			memcpy(&mreq.mr_address, ALL_ISS, ETH_ALEN);
		else
			memcpy(&mreq.mr_address, ALL_ESS, ETH_ALEN);

	} else {
		mreq.mr_type = PACKET_MR_ALLMULTI;
	}
#ifdef EXTREME_DEBUG
	if (IS_DEBUG_EVENTS)
		zlog_debug(
			"isis_multicast_join(): fd=%d, reg_to=%d, if_num=%d, address = %02x:%02x:%02x:%02x:%02x:%02x",
			fd, registerto, if_num, mreq.mr_address[0],
			mreq.mr_address[1], mreq.mr_address[2],
			mreq.mr_address[3], mreq.mr_address[4],
			mreq.mr_address[5]);
#endif /* EXTREME_DEBUG */
	if (setsockopt(fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq,
		       sizeof(struct packet_mreq))) {
		zlog_warn("isis_multicast_join(): setsockopt(): %s",
			  safe_strerror(errno));
		return ISIS_WARNING;
	}

	return ISIS_OK;
}

static int open_packet_socket(struct isis_circuit *circuit)
{
	struct sockaddr_ll s_addr;
	int fd, retval = ISIS_OK;
	struct vrf *vrf = NULL;

	vrf = circuit->interface->vrf;

	fd = vrf_socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_ALL), vrf->vrf_id,
			vrf->name);

	if (fd < 0) {
		zlog_warn("open_packet_socket(): socket() failed %s",
			  safe_strerror(errno));
		return ISIS_WARNING;
	}

	if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf, sizeof(bpf))) {
		zlog_warn("open_packet_socket(): SO_ATTACH_FILTER failed: %s",
			  safe_strerror(errno));
	}

	/*
	 * Bind to the physical interface
	 */
	memset(&s_addr, 0, sizeof(struct sockaddr_ll));
	s_addr.sll_family = AF_PACKET;
	s_addr.sll_protocol = htons(ETH_P_ALL);
	s_addr.sll_ifindex = circuit->interface->ifindex;

	if (bind(fd, (struct sockaddr *)(&s_addr), sizeof(struct sockaddr_ll))
	    < 0) {
		zlog_warn("open_packet_socket(): bind() failed: %s",
			  safe_strerror(errno));
		close(fd);
		return ISIS_WARNING;
	}

	circuit->fd = fd;

	if (if_is_broadcast(circuit->interface)) {
		/*
		 * Join to multicast groups
		 * according to
		 * 8.4.2 - Broadcast subnetwork IIH PDUs
		 * FIXME: is there a case only one will fail??
		 */
		/* joining ALL_L1_ISS */
		retval |= isis_multicast_join(circuit->fd, 1,
					      circuit->interface->ifindex);
		/* joining ALL_L2_ISS */
		retval |= isis_multicast_join(circuit->fd, 2,
					      circuit->interface->ifindex);
		/* joining ALL_ISS (used in RFC 5309 p2p-over-lan as well) */
		retval |= isis_multicast_join(circuit->fd, 3,
					      circuit->interface->ifindex);
	} else {
		retval = isis_multicast_join(circuit->fd, 0,
					     circuit->interface->ifindex);
	}

	return retval;
}

/*
 * Create the socket and set the tx/rx funcs
 */
int isis_sock_init(struct isis_circuit *circuit)
{
	int retval = ISIS_OK;

	frr_with_privs(&isisd_privs) {

		retval = open_packet_socket(circuit);

		if (retval != ISIS_OK) {
			zlog_warn("%s: could not initialize the socket",
				  __func__);
			break;
		}

	/* Assign Rx and Tx callbacks are based on real if type */
		if (if_is_broadcast(circuit->interface)) {
			circuit->tx = isis_send_pdu_bcast;
			circuit->rx = isis_recv_pdu_bcast;
		} else if (if_is_pointopoint(circuit->interface)) {
			circuit->tx = isis_send_pdu_p2p;
			circuit->rx = isis_recv_pdu_p2p;
		} else {
			zlog_warn("isis_sock_init(): unknown circuit type");
			retval = ISIS_WARNING;
			break;
		}
	}

	return retval;
}

static inline int llc_check(uint8_t *llc)
{
	if (*llc != ISO_SAP || *(llc + 1) != ISO_SAP || *(llc + 2) != 3)
		return 0;

	return 1;
}

int isis_recv_pdu_bcast(struct isis_circuit *circuit, uint8_t *ssnpa)
{
	int bytesread, addr_len;
	struct sockaddr_ll s_addr;
	uint8_t llc[LLC_LEN];

	addr_len = sizeof(s_addr);

	memset(&s_addr, 0, sizeof(struct sockaddr_ll));

	bytesread =
		recvfrom(circuit->fd, (void *)&llc, LLC_LEN, MSG_PEEK,
			 (struct sockaddr *)&s_addr, (socklen_t *)&addr_len);

	if ((bytesread < 0)
	    || (s_addr.sll_ifindex != (int)circuit->interface->ifindex)) {
		if (bytesread < 0) {
			zlog_warn(
				"isis_recv_packet_bcast(): ifname %s, fd %d, bytesread %d, recvfrom(): %s",
				circuit->interface->name, circuit->fd,
				bytesread, safe_strerror(errno));
		}
		if (s_addr.sll_ifindex != (int)circuit->interface->ifindex) {
			zlog_warn(
				"packet is received on multiple interfaces: socket interface %d, circuit interface %d, packet type %u",
				s_addr.sll_ifindex, circuit->interface->ifindex,
				s_addr.sll_pkttype);
		}

		/* get rid of the packet */
		bytesread = recvfrom(circuit->fd, discard_buff,
				     sizeof(discard_buff), MSG_DONTWAIT,
				     (struct sockaddr *)&s_addr,
				     (socklen_t *)&addr_len);

		if (bytesread < 0)
			zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");

		return ISIS_WARNING;
	}
	/*
	 * Filtering by llc field, discard packets sent by this host (other
	 * circuit)
	 */
	if (!llc_check(llc) || s_addr.sll_pkttype == PACKET_OUTGOING) {
		/*  Read the packet into discard buff */
		bytesread = recvfrom(circuit->fd, discard_buff,
				     sizeof(discard_buff), MSG_DONTWAIT,
				     (struct sockaddr *)&s_addr,
				     (socklen_t *)&addr_len);
		if (bytesread < 0)
			zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
		return ISIS_WARNING;
	}

	/* Ensure that we have enough space for a pdu padded to fill the mtu */
	unsigned int max_size =
		circuit->interface->mtu > circuit->interface->mtu6
			? circuit->interface->mtu
			: circuit->interface->mtu6;
	uint8_t temp_buff[max_size];
	bytesread =
		recvfrom(circuit->fd, temp_buff, max_size, MSG_DONTWAIT,
			 (struct sockaddr *)&s_addr, (socklen_t *)&addr_len);
	if (bytesread < 0) {
		zlog_warn("%s: recvfrom() failed", __func__);
		return ISIS_WARNING;
	}
	/* then we lose the LLC */
	stream_write(circuit->rcv_stream, temp_buff + LLC_LEN,
		     bytesread - LLC_LEN);
	memcpy(ssnpa, &s_addr.sll_addr, s_addr.sll_halen);

	return ISIS_OK;
}

int isis_recv_pdu_p2p(struct isis_circuit *circuit, uint8_t *ssnpa)
{
	int bytesread, addr_len;
	struct sockaddr_ll s_addr;

	memset(&s_addr, 0, sizeof(struct sockaddr_ll));
	addr_len = sizeof(s_addr);

	/* we can read directly to the stream */
	(void)stream_recvfrom(
		circuit->rcv_stream, circuit->fd, circuit->interface->mtu, 0,
		(struct sockaddr *)&s_addr, (socklen_t *)&addr_len);

	if (s_addr.sll_pkttype == PACKET_OUTGOING) {
		/*  Read the packet into discard buff */
		bytesread = recvfrom(circuit->fd, discard_buff,
				     sizeof(discard_buff), MSG_DONTWAIT,
				     (struct sockaddr *)&s_addr,
				     (socklen_t *)&addr_len);
		if (bytesread < 0)
			zlog_warn("isis_recv_pdu_p2p(): recvfrom() failed");
		return ISIS_WARNING;
	}

	/* If we don't have protocol type 0x00FE which is
	 * ISO over GRE we exit with pain :)
	 */
	if (ntohs(s_addr.sll_protocol) != 0x00FE) {
		zlog_warn("isis_recv_pdu_p2p(): protocol mismatch(): %X",
			  ntohs(s_addr.sll_protocol));
		return ISIS_WARNING;
	}

	memcpy(ssnpa, &s_addr.sll_addr, s_addr.sll_halen);

	return ISIS_OK;
}

int isis_send_pdu_bcast(struct isis_circuit *circuit, int level)
{
	struct msghdr msg;
	struct iovec iov[2];
	char temp_buff[LLC_LEN];

	/* we need to do the LLC in here because of P2P circuits, which will
	 * not need it
	 */
	struct sockaddr_ll sa;

	stream_set_getp(circuit->snd_stream, 0);
	memset(&sa, 0, sizeof(struct sockaddr_ll));
	sa.sll_family = AF_PACKET;

	size_t frame_size = stream_get_endp(circuit->snd_stream) + LLC_LEN;
	sa.sll_protocol = htons(isis_ethertype(frame_size));
	sa.sll_ifindex = circuit->interface->ifindex;
	sa.sll_halen = ETH_ALEN;
	/* RFC5309 section 4.1 recommends ALL_ISS */
	if (circuit->circ_type == CIRCUIT_T_P2P)
		memcpy(&sa.sll_addr, ALL_ISS, ETH_ALEN);
	else if (level == 1)
		memcpy(&sa.sll_addr, ALL_L1_ISS, ETH_ALEN);
	else
		memcpy(&sa.sll_addr, ALL_L2_ISS, ETH_ALEN);

	/* on a broadcast circuit */
	/* first we put the LLC in */
	temp_buff[0] = 0xFE;
	temp_buff[1] = 0xFE;
	temp_buff[2] = 0x03;

	memset(&msg, 0, sizeof(msg));
	msg.msg_name = &sa;
	msg.msg_namelen = sizeof(struct sockaddr_ll);
	msg.msg_iov = iov;
	msg.msg_iovlen = 2;
	iov[0].iov_base = temp_buff;
	iov[0].iov_len = LLC_LEN;
	iov[1].iov_base = circuit->snd_stream->data;
	iov[1].iov_len = stream_get_endp(circuit->snd_stream);

	if (sendmsg(circuit->fd, &msg, 0) < 0) {
		zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
			  circuit->interface->name, safe_strerror(errno));
		if (ERRNO_IO_RETRY(errno))
			return ISIS_WARNING;
		return ISIS_ERROR;
	}
	return ISIS_OK;
}

int isis_send_pdu_p2p(struct isis_circuit *circuit, int level)
{
	struct sockaddr_ll sa;
	ssize_t rv;

	stream_set_getp(circuit->snd_stream, 0);
	memset(&sa, 0, sizeof(struct sockaddr_ll));
	sa.sll_family = AF_PACKET;
	sa.sll_ifindex = circuit->interface->ifindex;
	sa.sll_halen = ETH_ALEN;
	if (level == 1)
		memcpy(&sa.sll_addr, ALL_L1_ISS, ETH_ALEN);
	else
		memcpy(&sa.sll_addr, ALL_L2_ISS, ETH_ALEN);


	/* lets try correcting the protocol */
	sa.sll_protocol = htons(0x00FE);
	rv = sendto(circuit->fd, circuit->snd_stream->data,
		    stream_get_endp(circuit->snd_stream), 0,
		    (struct sockaddr *)&sa, sizeof(struct sockaddr_ll));
	if (rv < 0) {
		zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
			  circuit->interface->name, safe_strerror(errno));
		if (ERRNO_IO_RETRY(errno))
			return ISIS_WARNING;
		return ISIS_ERROR;
	}
	return ISIS_OK;
}

#endif /* ISIS_METHOD == ISIS_METHOD_PFPACKET */
Commit	Line	Data
8bc98059 PJ	1	/*
	2	* IS-IS Rout(e)ing protocol - isis_pfpacket.c
	3	*
	4	* Copyright (C) 2001,2002 Sampo Saaristo
d62a17ae	5	* Tampere University of Technology
8bc98059 PJ	6	* Institute of Communications Engineering
8bc98059 PJ	7	*
d62a17ae	8	* This program is free software; you can redistribute it and/or modify it
	9	* under the terms of the GNU General Public Licenseas published by the Free
	10	* Software Foundation; either version 2 of the License, or (at your option)
8bc98059 PJ	11	* any later version.
8bc98059 PJ	12	*
d62a17ae	13	* This program is distributed in the hope that it will be useful,but WITHOUT
	14	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	15	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
8bc98059	16	* more details.
896014f4 DL	17	*
	18	* You should have received a copy of the GNU General Public License along
	19	* with this program; see the file COPYING; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
8bc98059 PJ	21	*/
	22
	23	#include <zebra.h>
745bf05f	24	#if ISIS_METHOD == ISIS_METHOD_PFPACKET
d62a17ae	25	#include <net/ethernet.h> /* the L2 protocols */
8bc98059 PJ	26	#include <netpacket/packet.h>
8bc98059 PJ	27
4fa80053 DL	28	#include <linux/filter.h>
4fa80053 DL	29
8bc98059	30	#include "log.h"
cfd1f27b	31	#include "network.h"
8bc98059 PJ	32	#include "stream.h"
8bc98059 PJ	33	#include "if.h"
38937bd5	34	#include "lib_errors.h"
caa18d49	35	#include "vrf.h"
8bc98059	36
8bc98059 PJ	37	#include "isisd/isis_constants.h"
	38	#include "isisd/isis_common.h"
	39	#include "isisd/isis_circuit.h"
	40	#include "isisd/isis_flags.h"
	41	#include "isisd/isisd.h"
	42	#include "isisd/isis_constants.h"
	43	#include "isisd/isis_circuit.h"
	44	#include "isisd/isis_network.h"
	45
	46	#include "privs.h"
	47
4fa80053	48	/* tcpdump -i eth0 'isis' -dd */
2b64873d	49	static const struct sock_filter isisfilter[] = {
996c9314 LB	50	/* NB: we're in SOCK_DGRAM, so src/dst mac + length are stripped
	51	* off!
	52	* (OTOH it's a bit more lower-layer agnostic and might work
	53	* over GRE?) */
	54	/* { 0x28, 0, 0, 0x0000000c - 14 }, */
	55	/* { 0x25, 5, 0, 0x000005dc }, */
	56	{0x28, 0, 0, 0x0000000e - 14}, {0x15, 0, 3, 0x0000fefe},
	57	{0x30, 0, 0, 0x00000011 - 14}, {0x15, 0, 1, 0x00000083},
	58	{0x6, 0, 0, 0x00040000}, {0x6, 0, 0, 0x00000000},
4fa80053 DL	59	};
4fa80053 DL	60
2b64873d	61	static const struct sock_fprog bpf = {
4fa80053	62	.len = array_size(isisfilter),
2b64873d	63	.filter = (struct sock_filter *)isisfilter,
4fa80053 DL	64	};
4fa80053 DL	65
8bc98059 PJ	66	/*
	67	* Table 9 - Architectural constants for use with ISO 8802 subnetworks
	68	* ISO 10589 - 8.4.8
	69	*/
	70
2b64873d DL	71	static const uint8_t ALL_L1_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
	72	static const uint8_t ALL_L2_ISS[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
	73	static const uint8_t ALL_ISS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
	74	static const uint8_t ALL_ESS[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
8bc98059	75
f2bce9a5	76	static uint8_t discard_buff[8192];
8bc98059 PJ	77
	78	/*
	79	* if level is 0 we are joining p2p multicast
	80	* FIXME: and the p2p multicast being ???
	81	*/
d62a17ae	82	static int isis_multicast_join(int fd, int registerto, int if_num)
8bc98059	83	{
d62a17ae	84	struct packet_mreq mreq;
	85
	86	memset(&mreq, 0, sizeof(mreq));
	87	mreq.mr_ifindex = if_num;
	88	if (registerto) {
	89	mreq.mr_type = PACKET_MR_MULTICAST;
	90	mreq.mr_alen = ETH_ALEN;
	91	if (registerto == 1)
	92	memcpy(&mreq.mr_address, ALL_L1_ISS, ETH_ALEN);
	93	else if (registerto == 2)
	94	memcpy(&mreq.mr_address, ALL_L2_ISS, ETH_ALEN);
	95	else if (registerto == 3)
	96	memcpy(&mreq.mr_address, ALL_ISS, ETH_ALEN);
	97	else
	98	memcpy(&mreq.mr_address, ALL_ESS, ETH_ALEN);
	99
	100	} else {
	101	mreq.mr_type = PACKET_MR_ALLMULTI;
	102	}
8bc98059	103	#ifdef EXTREME_DEBUG
b0814935 PG	104	if (IS_DEBUG_EVENTS)
	105	zlog_debug(
	106	"isis_multicast_join(): fd=%d, reg_to=%d, if_num=%d, address = %02x:%02x:%02x:%02x:%02x:%02x",
	107	fd, registerto, if_num, mreq.mr_address[0],
	108	mreq.mr_address[1], mreq.mr_address[2],
	109	mreq.mr_address[3], mreq.mr_address[4],
	110	mreq.mr_address[5]);
8bc98059	111	#endif /* EXTREME_DEBUG */
d62a17ae	112	if (setsockopt(fd, SOL_PACKET, PACKET_ADD_MEMBERSHIP, &mreq,
	113	sizeof(struct packet_mreq))) {
	114	zlog_warn("isis_multicast_join(): setsockopt(): %s",
	115	safe_strerror(errno));
	116	return ISIS_WARNING;
	117	}
	118
	119	return ISIS_OK;
8bc98059 PJ	120	}
8bc98059 PJ	121
d62a17ae	122	static int open_packet_socket(struct isis_circuit *circuit)
8bc98059	123	{
d62a17ae	124	struct sockaddr_ll s_addr;
d62a17ae	125	int fd, retval = ISIS_OK;
caa18d49 K	126	struct vrf *vrf = NULL;
caa18d49 K	127
096f7609	128	vrf = circuit->interface->vrf;
caa18d49	129
096f7609 IR	130	fd = vrf_socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_ALL), vrf->vrf_id,
096f7609 IR	131	vrf->name);
d62a17ae	132
d62a17ae	133	if (fd < 0) {
	134	zlog_warn("open_packet_socket(): socket() failed %s",
	135	safe_strerror(errno));
	136	return ISIS_WARNING;
	137	}
	138
	139	if (setsockopt(fd, SOL_SOCKET, SO_ATTACH_FILTER, &bpf, sizeof(bpf))) {
	140	zlog_warn("open_packet_socket(): SO_ATTACH_FILTER failed: %s",
	141	safe_strerror(errno));
	142	}
	143
	144	/*
	145	* Bind to the physical interface
	146	*/
	147	memset(&s_addr, 0, sizeof(struct sockaddr_ll));
	148	s_addr.sll_family = AF_PACKET;
	149	s_addr.sll_protocol = htons(ETH_P_ALL);
	150	s_addr.sll_ifindex = circuit->interface->ifindex;
	151
	152	if (bind(fd, (struct sockaddr *)(&s_addr), sizeof(struct sockaddr_ll))
	153	< 0) {
	154	zlog_warn("open_packet_socket(): bind() failed: %s",
	155	safe_strerror(errno));
	156	close(fd);
	157	return ISIS_WARNING;
	158	}
	159
	160	circuit->fd = fd;
	161
	162	if (if_is_broadcast(circuit->interface)) {
	163	/*
	164	* Join to multicast groups
	165	* according to
	166	* 8.4.2 - Broadcast subnetwork IIH PDUs
	167	* FIXME: is there a case only one will fail??
	168	*/
	169	/* joining ALL_L1_ISS */
	170	retval \|= isis_multicast_join(circuit->fd, 1,
	171	circuit->interface->ifindex);
	172	/* joining ALL_L2_ISS */
	173	retval \|= isis_multicast_join(circuit->fd, 2,
	174	circuit->interface->ifindex);
	175	/* joining ALL_ISS (used in RFC 5309 p2p-over-lan as well) */
	176	retval \|= isis_multicast_join(circuit->fd, 3,
	177	circuit->interface->ifindex);
	178	} else {
	179	retval = isis_multicast_join(circuit->fd, 0,
	180	circuit->interface->ifindex);
	181	}
	182
	183	return retval;
8bc98059 PJ	184	}
	185
	186	/*
	187	* Create the socket and set the tx/rx funcs
	188	*/
d62a17ae	189	int isis_sock_init(struct isis_circuit *circuit)
8bc98059	190	{
d62a17ae	191	int retval = ISIS_OK;
d62a17ae	192
0cf6db21	193	frr_with_privs(&isisd_privs) {
d62a17ae	194
01b9e3fd	195	retval = open_packet_socket(circuit);
d62a17ae	196
01b9e3fd	197	if (retval != ISIS_OK) {
633fc9b1 DL	198	zlog_warn("%s: could not initialize the socket",
633fc9b1 DL	199	__func__);
01b9e3fd DL	200	break;
01b9e3fd DL	201	}
d62a17ae	202
d62a17ae	203	/* Assign Rx and Tx callbacks are based on real if type */
01b9e3fd DL	204	if (if_is_broadcast(circuit->interface)) {
	205	circuit->tx = isis_send_pdu_bcast;
	206	circuit->rx = isis_recv_pdu_bcast;
	207	} else if (if_is_pointopoint(circuit->interface)) {
	208	circuit->tx = isis_send_pdu_p2p;
	209	circuit->rx = isis_recv_pdu_p2p;
	210	} else {
	211	zlog_warn("isis_sock_init(): unknown circuit type");
	212	retval = ISIS_WARNING;
	213	break;
	214	}
633fc9b1	215	}
8bc98059	216
d62a17ae	217	return retval;
8bc98059 PJ	218	}
8bc98059 PJ	219
d7c0a89a	220	static inline int llc_check(uint8_t *llc)
8bc98059	221	{
d62a17ae	222	if (llc != ISO_SAP \|\| (llc + 1) != ISO_SAP \|\| *(llc + 2) != 3)
d62a17ae	223	return 0;
8bc98059	224
d62a17ae	225	return 1;
8bc98059 PJ	226	}
8bc98059 PJ	227
d7c0a89a	228	int isis_recv_pdu_bcast(struct isis_circuit circuit, uint8_t ssnpa)
8bc98059	229	{
d62a17ae	230	int bytesread, addr_len;
d62a17ae	231	struct sockaddr_ll s_addr;
d7c0a89a	232	uint8_t llc[LLC_LEN];
d62a17ae	233
	234	addr_len = sizeof(s_addr);
	235
	236	memset(&s_addr, 0, sizeof(struct sockaddr_ll));
	237
	238	bytesread =
	239	recvfrom(circuit->fd, (void *)&llc, LLC_LEN, MSG_PEEK,
	240	(struct sockaddr )&s_addr, (socklen_t )&addr_len);
	241
	242	if ((bytesread < 0)
	243	\|\| (s_addr.sll_ifindex != (int)circuit->interface->ifindex)) {
	244	if (bytesread < 0) {
	245	zlog_warn(
3efd0893	246	"isis_recv_packet_bcast(): ifname %s, fd %d, bytesread %d, recvfrom(): %s",
d62a17ae	247	circuit->interface->name, circuit->fd,
	248	bytesread, safe_strerror(errno));
	249	}
	250	if (s_addr.sll_ifindex != (int)circuit->interface->ifindex) {
	251	zlog_warn(
3efd0893	252	"packet is received on multiple interfaces: socket interface %d, circuit interface %d, packet type %u",
d62a17ae	253	s_addr.sll_ifindex, circuit->interface->ifindex,
	254	s_addr.sll_pkttype);
	255	}
	256
	257	/* get rid of the packet */
	258	bytesread = recvfrom(circuit->fd, discard_buff,
	259	sizeof(discard_buff), MSG_DONTWAIT,
	260	(struct sockaddr *)&s_addr,
	261	(socklen_t *)&addr_len);
	262
	263	if (bytesread < 0)
	264	zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
	265
	266	return ISIS_WARNING;
	267	}
	268	/*
	269	* Filtering by llc field, discard packets sent by this host (other
	270	* circuit)
	271	*/
	272	if (!llc_check(llc) \|\| s_addr.sll_pkttype == PACKET_OUTGOING) {
	273	/* Read the packet into discard buff */
	274	bytesread = recvfrom(circuit->fd, discard_buff,
	275	sizeof(discard_buff), MSG_DONTWAIT,
	276	(struct sockaddr *)&s_addr,
	277	(socklen_t *)&addr_len);
	278	if (bytesread < 0)
	279	zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
	280	return ISIS_WARNING;
	281	}
	282
32fed393 EDP	283	/* Ensure that we have enough space for a pdu padded to fill the mtu */
	284	unsigned int max_size =
	285	circuit->interface->mtu > circuit->interface->mtu6
	286	? circuit->interface->mtu
	287	: circuit->interface->mtu6;
	288	uint8_t temp_buff[max_size];
	289	bytesread =
	290	recvfrom(circuit->fd, temp_buff, max_size, MSG_DONTWAIT,
	291	(struct sockaddr )&s_addr, (socklen_t )&addr_len);
d62a17ae	292	if (bytesread < 0) {
32fed393	293	zlog_warn("%s: recvfrom() failed", __func__);
d62a17ae	294	return ISIS_WARNING;
d62a17ae	295	}
d62a17ae	296	/* then we lose the LLC */
32fed393	297	stream_write(circuit->rcv_stream, temp_buff + LLC_LEN,
d62a17ae	298	bytesread - LLC_LEN);
d62a17ae	299	memcpy(ssnpa, &s_addr.sll_addr, s_addr.sll_halen);
	300
	301	return ISIS_OK;
8bc98059 PJ	302	}
8bc98059 PJ	303
d7c0a89a	304	int isis_recv_pdu_p2p(struct isis_circuit circuit, uint8_t ssnpa)
8bc98059	305	{
d62a17ae	306	int bytesread, addr_len;
	307	struct sockaddr_ll s_addr;
	308
	309	memset(&s_addr, 0, sizeof(struct sockaddr_ll));
	310	addr_len = sizeof(s_addr);
	311
	312	/* we can read directly to the stream */
aa979109 A	313	(void)stream_recvfrom(
	314	circuit->rcv_stream, circuit->fd, circuit->interface->mtu, 0,
	315	(struct sockaddr )&s_addr, (socklen_t )&addr_len);
d62a17ae	316
	317	if (s_addr.sll_pkttype == PACKET_OUTGOING) {
	318	/* Read the packet into discard buff */
	319	bytesread = recvfrom(circuit->fd, discard_buff,
	320	sizeof(discard_buff), MSG_DONTWAIT,
	321	(struct sockaddr *)&s_addr,
	322	(socklen_t *)&addr_len);
	323	if (bytesread < 0)
	324	zlog_warn("isis_recv_pdu_p2p(): recvfrom() failed");
	325	return ISIS_WARNING;
	326	}
	327
	328	/* If we don't have protocol type 0x00FE which is
	329	* ISO over GRE we exit with pain :)
	330	*/
	331	if (ntohs(s_addr.sll_protocol) != 0x00FE) {
	332	zlog_warn("isis_recv_pdu_p2p(): protocol mismatch(): %X",
	333	ntohs(s_addr.sll_protocol));
	334	return ISIS_WARNING;
	335	}
	336
	337	memcpy(ssnpa, &s_addr.sll_addr, s_addr.sll_halen);
	338
	339	return ISIS_OK;
8bc98059 PJ	340	}
8bc98059 PJ	341
d62a17ae	342	int isis_send_pdu_bcast(struct isis_circuit *circuit, int level)
8bc98059	343	{
d62a17ae	344	struct msghdr msg;
d62a17ae	345	struct iovec iov[2];
32fed393	346	char temp_buff[LLC_LEN];
d62a17ae	347
	348	/* we need to do the LLC in here because of P2P circuits, which will
	349	* not need it
	350	*/
	351	struct sockaddr_ll sa;
	352
	353	stream_set_getp(circuit->snd_stream, 0);
	354	memset(&sa, 0, sizeof(struct sockaddr_ll));
	355	sa.sll_family = AF_PACKET;
	356
	357	size_t frame_size = stream_get_endp(circuit->snd_stream) + LLC_LEN;
	358	sa.sll_protocol = htons(isis_ethertype(frame_size));
	359	sa.sll_ifindex = circuit->interface->ifindex;
	360	sa.sll_halen = ETH_ALEN;
	361	/* RFC5309 section 4.1 recommends ALL_ISS */
	362	if (circuit->circ_type == CIRCUIT_T_P2P)
	363	memcpy(&sa.sll_addr, ALL_ISS, ETH_ALEN);
	364	else if (level == 1)
	365	memcpy(&sa.sll_addr, ALL_L1_ISS, ETH_ALEN);
	366	else
	367	memcpy(&sa.sll_addr, ALL_L2_ISS, ETH_ALEN);
	368
	369	/* on a broadcast circuit */
	370	/* first we put the LLC in */
32fed393 EDP	371	temp_buff[0] = 0xFE;
	372	temp_buff[1] = 0xFE;
	373	temp_buff[2] = 0x03;
d62a17ae	374
	375	memset(&msg, 0, sizeof(msg));
	376	msg.msg_name = &sa;
	377	msg.msg_namelen = sizeof(struct sockaddr_ll);
	378	msg.msg_iov = iov;
	379	msg.msg_iovlen = 2;
32fed393	380	iov[0].iov_base = temp_buff;
d62a17ae	381	iov[0].iov_len = LLC_LEN;
	382	iov[1].iov_base = circuit->snd_stream->data;
	383	iov[1].iov_len = stream_get_endp(circuit->snd_stream);
	384
	385	if (sendmsg(circuit->fd, &msg, 0) < 0) {
	386	zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
	387	circuit->interface->name, safe_strerror(errno));
	388	if (ERRNO_IO_RETRY(errno))
	389	return ISIS_WARNING;
	390	return ISIS_ERROR;
	391	}
	392	return ISIS_OK;
8bc98059 PJ	393	}
8bc98059 PJ	394
d62a17ae	395	int isis_send_pdu_p2p(struct isis_circuit *circuit, int level)
8bc98059	396	{
d62a17ae	397	struct sockaddr_ll sa;
	398	ssize_t rv;
	399
	400	stream_set_getp(circuit->snd_stream, 0);
	401	memset(&sa, 0, sizeof(struct sockaddr_ll));
	402	sa.sll_family = AF_PACKET;
	403	sa.sll_ifindex = circuit->interface->ifindex;
	404	sa.sll_halen = ETH_ALEN;
	405	if (level == 1)
	406	memcpy(&sa.sll_addr, ALL_L1_ISS, ETH_ALEN);
	407	else
	408	memcpy(&sa.sll_addr, ALL_L2_ISS, ETH_ALEN);
	409
	410
	411	/* lets try correcting the protocol */
	412	sa.sll_protocol = htons(0x00FE);
	413	rv = sendto(circuit->fd, circuit->snd_stream->data,
	414	stream_get_endp(circuit->snd_stream), 0,
	415	(struct sockaddr *)&sa, sizeof(struct sockaddr_ll));
	416	if (rv < 0) {
	417	zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
	418	circuit->interface->name, safe_strerror(errno));
	419	if (ERRNO_IO_RETRY(errno))
	420	return ISIS_WARNING;
	421	return ISIS_ERROR;
	422	}
	423	return ISIS_OK;
8bc98059	424	}
745bf05f DL	425
745bf05f DL	426	#endif /* ISIS_METHOD == ISIS_METHOD_PFPACKET */