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2 * IS-IS Rout(e)ing protocol - isis_pfpacket.c
4 * Copyright (C) 2001,2002 Sampo Saaristo
5 * Tampere University of Technology
6 * Institute of Communications Engineering
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)
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
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
24 #if ISIS_METHOD == ISIS_METHOD_PFPACKET
25 #include <net/ethernet.h> /* the L2 protocols */
26 #include <netpacket/packet.h>
28 #include <linux/filter.h>
34 #include "lib_errors.h"
36 #include "isisd/dict.h"
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"
48 /* tcpdump -i eth0 'isis' -dd */
49 static struct sock_filter isisfilter
[] = {
50 /* NB: we're in SOCK_DGRAM, so src/dst mac + length are stripped
52 * (OTOH it's a bit more lower-layer agnostic and might work
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},
61 static struct sock_fprog bpf
= {
62 .len
= array_size(isisfilter
),
67 * Table 9 - Architectural constants for use with ISO 8802 subnetworks
71 uint8_t ALL_L1_ISS
[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
72 uint8_t ALL_L2_ISS
[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
73 uint8_t ALL_ISS
[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
74 uint8_t ALL_ESS
[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
76 static uint8_t discard_buff
[8192];
77 static uint8_t sock_buff
[8192];
80 * if level is 0 we are joining p2p multicast
81 * FIXME: and the p2p multicast being ???
83 static int isis_multicast_join(int fd
, int registerto
, int if_num
)
85 struct packet_mreq mreq
;
87 memset(&mreq
, 0, sizeof(mreq
));
88 mreq
.mr_ifindex
= if_num
;
90 mreq
.mr_type
= PACKET_MR_MULTICAST
;
91 mreq
.mr_alen
= ETH_ALEN
;
93 memcpy(&mreq
.mr_address
, ALL_L1_ISS
, ETH_ALEN
);
94 else if (registerto
== 2)
95 memcpy(&mreq
.mr_address
, ALL_L2_ISS
, ETH_ALEN
);
96 else if (registerto
== 3)
97 memcpy(&mreq
.mr_address
, ALL_ISS
, ETH_ALEN
);
99 memcpy(&mreq
.mr_address
, ALL_ESS
, ETH_ALEN
);
102 mreq
.mr_type
= PACKET_MR_ALLMULTI
;
106 "isis_multicast_join(): fd=%d, reg_to=%d, if_num=%d, "
107 "address = %02x:%02x:%02x:%02x:%02x:%02x",
108 fd
, registerto
, if_num
, mreq
.mr_address
[0], mreq
.mr_address
[1],
109 mreq
.mr_address
[2], mreq
.mr_address
[3], mreq
.mr_address
[4],
111 #endif /* EXTREME_DEBUG */
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
));
122 static int open_packet_socket(struct isis_circuit
*circuit
)
124 struct sockaddr_ll s_addr
;
125 int fd
, retval
= ISIS_OK
;
127 fd
= socket(PF_PACKET
, SOCK_DGRAM
, htons(ETH_P_ALL
));
129 zlog_warn("open_packet_socket(): socket() failed %s",
130 safe_strerror(errno
));
134 if (setsockopt(fd
, SOL_SOCKET
, SO_ATTACH_FILTER
, &bpf
, sizeof(bpf
))) {
135 zlog_warn("open_packet_socket(): SO_ATTACH_FILTER failed: %s",
136 safe_strerror(errno
));
140 * Bind to the physical interface
142 memset(&s_addr
, 0, sizeof(struct sockaddr_ll
));
143 s_addr
.sll_family
= AF_PACKET
;
144 s_addr
.sll_protocol
= htons(ETH_P_ALL
);
145 s_addr
.sll_ifindex
= circuit
->interface
->ifindex
;
147 if (bind(fd
, (struct sockaddr
*)(&s_addr
), sizeof(struct sockaddr_ll
))
149 zlog_warn("open_packet_socket(): bind() failed: %s",
150 safe_strerror(errno
));
157 if (if_is_broadcast(circuit
->interface
)) {
159 * Join to multicast groups
161 * 8.4.2 - Broadcast subnetwork IIH PDUs
162 * FIXME: is there a case only one will fail??
164 /* joining ALL_L1_ISS */
165 retval
|= isis_multicast_join(circuit
->fd
, 1,
166 circuit
->interface
->ifindex
);
167 /* joining ALL_L2_ISS */
168 retval
|= isis_multicast_join(circuit
->fd
, 2,
169 circuit
->interface
->ifindex
);
170 /* joining ALL_ISS (used in RFC 5309 p2p-over-lan as well) */
171 retval
|= isis_multicast_join(circuit
->fd
, 3,
172 circuit
->interface
->ifindex
);
174 retval
= isis_multicast_join(circuit
->fd
, 0,
175 circuit
->interface
->ifindex
);
182 * Create the socket and set the tx/rx funcs
184 int isis_sock_init(struct isis_circuit
*circuit
)
186 int retval
= ISIS_OK
;
188 frr_elevate_privs(&isisd_privs
) {
190 retval
= open_packet_socket(circuit
);
192 if (retval
!= ISIS_OK
) {
193 zlog_warn("%s: could not initialize the socket",
198 /* Assign Rx and Tx callbacks are based on real if type */
199 if (if_is_broadcast(circuit
->interface
)) {
200 circuit
->tx
= isis_send_pdu_bcast
;
201 circuit
->rx
= isis_recv_pdu_bcast
;
202 } else if (if_is_pointopoint(circuit
->interface
)) {
203 circuit
->tx
= isis_send_pdu_p2p
;
204 circuit
->rx
= isis_recv_pdu_p2p
;
206 zlog_warn("isis_sock_init(): unknown circuit type");
207 retval
= ISIS_WARNING
;
215 static inline int llc_check(uint8_t *llc
)
217 if (*llc
!= ISO_SAP
|| *(llc
+ 1) != ISO_SAP
|| *(llc
+ 2) != 3)
223 int isis_recv_pdu_bcast(struct isis_circuit
*circuit
, uint8_t *ssnpa
)
225 int bytesread
, addr_len
;
226 struct sockaddr_ll s_addr
;
227 uint8_t llc
[LLC_LEN
];
229 addr_len
= sizeof(s_addr
);
231 memset(&s_addr
, 0, sizeof(struct sockaddr_ll
));
234 recvfrom(circuit
->fd
, (void *)&llc
, LLC_LEN
, MSG_PEEK
,
235 (struct sockaddr
*)&s_addr
, (socklen_t
*)&addr_len
);
238 || (s_addr
.sll_ifindex
!= (int)circuit
->interface
->ifindex
)) {
241 "isis_recv_packet_bcast(): ifname %s, fd %d, "
242 "bytesread %d, recvfrom(): %s",
243 circuit
->interface
->name
, circuit
->fd
,
244 bytesread
, safe_strerror(errno
));
246 if (s_addr
.sll_ifindex
!= (int)circuit
->interface
->ifindex
) {
248 "packet is received on multiple interfaces: "
249 "socket interface %d, circuit interface %d, "
251 s_addr
.sll_ifindex
, circuit
->interface
->ifindex
,
255 /* get rid of the packet */
256 bytesread
= recvfrom(circuit
->fd
, discard_buff
,
257 sizeof(discard_buff
), MSG_DONTWAIT
,
258 (struct sockaddr
*)&s_addr
,
259 (socklen_t
*)&addr_len
);
262 zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
267 * Filtering by llc field, discard packets sent by this host (other
270 if (!llc_check(llc
) || s_addr
.sll_pkttype
== PACKET_OUTGOING
) {
271 /* Read the packet into discard buff */
272 bytesread
= recvfrom(circuit
->fd
, discard_buff
,
273 sizeof(discard_buff
), MSG_DONTWAIT
,
274 (struct sockaddr
*)&s_addr
,
275 (socklen_t
*)&addr_len
);
277 zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
281 /* on lan we have to read to the static buff first */
282 bytesread
= recvfrom(circuit
->fd
, sock_buff
, sizeof(sock_buff
),
283 MSG_DONTWAIT
, (struct sockaddr
*)&s_addr
,
284 (socklen_t
*)&addr_len
);
286 zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
290 /* then we lose the LLC */
291 stream_write(circuit
->rcv_stream
, sock_buff
+ LLC_LEN
,
292 bytesread
- LLC_LEN
);
294 memcpy(ssnpa
, &s_addr
.sll_addr
, s_addr
.sll_halen
);
299 int isis_recv_pdu_p2p(struct isis_circuit
*circuit
, uint8_t *ssnpa
)
301 int bytesread
, addr_len
;
302 struct sockaddr_ll s_addr
;
304 memset(&s_addr
, 0, sizeof(struct sockaddr_ll
));
305 addr_len
= sizeof(s_addr
);
307 /* we can read directly to the stream */
308 (void)stream_recvfrom(
309 circuit
->rcv_stream
, circuit
->fd
, circuit
->interface
->mtu
, 0,
310 (struct sockaddr
*)&s_addr
, (socklen_t
*)&addr_len
);
312 if (s_addr
.sll_pkttype
== PACKET_OUTGOING
) {
313 /* Read the packet into discard buff */
314 bytesread
= recvfrom(circuit
->fd
, discard_buff
,
315 sizeof(discard_buff
), MSG_DONTWAIT
,
316 (struct sockaddr
*)&s_addr
,
317 (socklen_t
*)&addr_len
);
319 zlog_warn("isis_recv_pdu_p2p(): recvfrom() failed");
323 /* If we don't have protocol type 0x00FE which is
324 * ISO over GRE we exit with pain :)
326 if (ntohs(s_addr
.sll_protocol
) != 0x00FE) {
327 zlog_warn("isis_recv_pdu_p2p(): protocol mismatch(): %X",
328 ntohs(s_addr
.sll_protocol
));
332 memcpy(ssnpa
, &s_addr
.sll_addr
, s_addr
.sll_halen
);
337 int isis_send_pdu_bcast(struct isis_circuit
*circuit
, int level
)
342 /* we need to do the LLC in here because of P2P circuits, which will
345 struct sockaddr_ll sa
;
347 stream_set_getp(circuit
->snd_stream
, 0);
348 memset(&sa
, 0, sizeof(struct sockaddr_ll
));
349 sa
.sll_family
= AF_PACKET
;
351 size_t frame_size
= stream_get_endp(circuit
->snd_stream
) + LLC_LEN
;
352 sa
.sll_protocol
= htons(isis_ethertype(frame_size
));
353 sa
.sll_ifindex
= circuit
->interface
->ifindex
;
354 sa
.sll_halen
= ETH_ALEN
;
355 /* RFC5309 section 4.1 recommends ALL_ISS */
356 if (circuit
->circ_type
== CIRCUIT_T_P2P
)
357 memcpy(&sa
.sll_addr
, ALL_ISS
, ETH_ALEN
);
359 memcpy(&sa
.sll_addr
, ALL_L1_ISS
, ETH_ALEN
);
361 memcpy(&sa
.sll_addr
, ALL_L2_ISS
, ETH_ALEN
);
363 /* on a broadcast circuit */
364 /* first we put the LLC in */
369 memset(&msg
, 0, sizeof(msg
));
371 msg
.msg_namelen
= sizeof(struct sockaddr_ll
);
374 iov
[0].iov_base
= sock_buff
;
375 iov
[0].iov_len
= LLC_LEN
;
376 iov
[1].iov_base
= circuit
->snd_stream
->data
;
377 iov
[1].iov_len
= stream_get_endp(circuit
->snd_stream
);
379 if (sendmsg(circuit
->fd
, &msg
, 0) < 0) {
380 zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
381 circuit
->interface
->name
, safe_strerror(errno
));
382 if (ERRNO_IO_RETRY(errno
))
389 int isis_send_pdu_p2p(struct isis_circuit
*circuit
, int level
)
391 struct sockaddr_ll sa
;
394 stream_set_getp(circuit
->snd_stream
, 0);
395 memset(&sa
, 0, sizeof(struct sockaddr_ll
));
396 sa
.sll_family
= AF_PACKET
;
397 sa
.sll_ifindex
= circuit
->interface
->ifindex
;
398 sa
.sll_halen
= ETH_ALEN
;
400 memcpy(&sa
.sll_addr
, ALL_L1_ISS
, ETH_ALEN
);
402 memcpy(&sa
.sll_addr
, ALL_L2_ISS
, ETH_ALEN
);
405 /* lets try correcting the protocol */
406 sa
.sll_protocol
= htons(0x00FE);
407 rv
= sendto(circuit
->fd
, circuit
->snd_stream
->data
,
408 stream_get_endp(circuit
->snd_stream
), 0,
409 (struct sockaddr
*)&sa
, sizeof(struct sockaddr_ll
));
411 zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
412 circuit
->interface
->name
, safe_strerror(errno
));
413 if (ERRNO_IO_RETRY(errno
))
420 #endif /* ISIS_METHOD == ISIS_METHOD_PFPACKET */