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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/isis_constants.h"
37 #include "isisd/isis_common.h"
38 #include "isisd/isis_circuit.h"
39 #include "isisd/isis_flags.h"
40 #include "isisd/isisd.h"
41 #include "isisd/isis_constants.h"
42 #include "isisd/isis_circuit.h"
43 #include "isisd/isis_network.h"
47 /* tcpdump -i eth0 'isis' -dd */
48 static struct sock_filter isisfilter
[] = {
49 /* NB: we're in SOCK_DGRAM, so src/dst mac + length are stripped
51 * (OTOH it's a bit more lower-layer agnostic and might work
53 /* { 0x28, 0, 0, 0x0000000c - 14 }, */
54 /* { 0x25, 5, 0, 0x000005dc }, */
55 {0x28, 0, 0, 0x0000000e - 14}, {0x15, 0, 3, 0x0000fefe},
56 {0x30, 0, 0, 0x00000011 - 14}, {0x15, 0, 1, 0x00000083},
57 {0x6, 0, 0, 0x00040000}, {0x6, 0, 0, 0x00000000},
60 static struct sock_fprog bpf
= {
61 .len
= array_size(isisfilter
),
66 * Table 9 - Architectural constants for use with ISO 8802 subnetworks
70 uint8_t ALL_L1_ISS
[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x14};
71 uint8_t ALL_L2_ISS
[6] = {0x01, 0x80, 0xC2, 0x00, 0x00, 0x15};
72 uint8_t ALL_ISS
[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x05};
73 uint8_t ALL_ESS
[6] = {0x09, 0x00, 0x2B, 0x00, 0x00, 0x04};
75 static uint8_t discard_buff
[8192];
78 * if level is 0 we are joining p2p multicast
79 * FIXME: and the p2p multicast being ???
81 static int isis_multicast_join(int fd
, int registerto
, int if_num
)
83 struct packet_mreq mreq
;
85 memset(&mreq
, 0, sizeof(mreq
));
86 mreq
.mr_ifindex
= if_num
;
88 mreq
.mr_type
= PACKET_MR_MULTICAST
;
89 mreq
.mr_alen
= ETH_ALEN
;
91 memcpy(&mreq
.mr_address
, ALL_L1_ISS
, ETH_ALEN
);
92 else if (registerto
== 2)
93 memcpy(&mreq
.mr_address
, ALL_L2_ISS
, ETH_ALEN
);
94 else if (registerto
== 3)
95 memcpy(&mreq
.mr_address
, ALL_ISS
, ETH_ALEN
);
97 memcpy(&mreq
.mr_address
, ALL_ESS
, ETH_ALEN
);
100 mreq
.mr_type
= PACKET_MR_ALLMULTI
;
104 "isis_multicast_join(): fd=%d, reg_to=%d, if_num=%d, "
105 "address = %02x:%02x:%02x:%02x:%02x:%02x",
106 fd
, registerto
, if_num
, mreq
.mr_address
[0], mreq
.mr_address
[1],
107 mreq
.mr_address
[2], mreq
.mr_address
[3], mreq
.mr_address
[4],
109 #endif /* EXTREME_DEBUG */
110 if (setsockopt(fd
, SOL_PACKET
, PACKET_ADD_MEMBERSHIP
, &mreq
,
111 sizeof(struct packet_mreq
))) {
112 zlog_warn("isis_multicast_join(): setsockopt(): %s",
113 safe_strerror(errno
));
120 static int open_packet_socket(struct isis_circuit
*circuit
)
122 struct sockaddr_ll s_addr
;
123 int fd
, retval
= ISIS_OK
;
125 fd
= socket(PF_PACKET
, SOCK_DGRAM
, htons(ETH_P_ALL
));
127 zlog_warn("open_packet_socket(): socket() failed %s",
128 safe_strerror(errno
));
132 if (setsockopt(fd
, SOL_SOCKET
, SO_ATTACH_FILTER
, &bpf
, sizeof(bpf
))) {
133 zlog_warn("open_packet_socket(): SO_ATTACH_FILTER failed: %s",
134 safe_strerror(errno
));
138 * Bind to the physical interface
140 memset(&s_addr
, 0, sizeof(struct sockaddr_ll
));
141 s_addr
.sll_family
= AF_PACKET
;
142 s_addr
.sll_protocol
= htons(ETH_P_ALL
);
143 s_addr
.sll_ifindex
= circuit
->interface
->ifindex
;
145 if (bind(fd
, (struct sockaddr
*)(&s_addr
), sizeof(struct sockaddr_ll
))
147 zlog_warn("open_packet_socket(): bind() failed: %s",
148 safe_strerror(errno
));
155 if (if_is_broadcast(circuit
->interface
)) {
157 * Join to multicast groups
159 * 8.4.2 - Broadcast subnetwork IIH PDUs
160 * FIXME: is there a case only one will fail??
162 /* joining ALL_L1_ISS */
163 retval
|= isis_multicast_join(circuit
->fd
, 1,
164 circuit
->interface
->ifindex
);
165 /* joining ALL_L2_ISS */
166 retval
|= isis_multicast_join(circuit
->fd
, 2,
167 circuit
->interface
->ifindex
);
168 /* joining ALL_ISS (used in RFC 5309 p2p-over-lan as well) */
169 retval
|= isis_multicast_join(circuit
->fd
, 3,
170 circuit
->interface
->ifindex
);
172 retval
= isis_multicast_join(circuit
->fd
, 0,
173 circuit
->interface
->ifindex
);
180 * Create the socket and set the tx/rx funcs
182 int isis_sock_init(struct isis_circuit
*circuit
)
184 int retval
= ISIS_OK
;
186 frr_elevate_privs(&isisd_privs
) {
188 retval
= open_packet_socket(circuit
);
190 if (retval
!= ISIS_OK
) {
191 zlog_warn("%s: could not initialize the socket",
196 /* Assign Rx and Tx callbacks are based on real if type */
197 if (if_is_broadcast(circuit
->interface
)) {
198 circuit
->tx
= isis_send_pdu_bcast
;
199 circuit
->rx
= isis_recv_pdu_bcast
;
200 } else if (if_is_pointopoint(circuit
->interface
)) {
201 circuit
->tx
= isis_send_pdu_p2p
;
202 circuit
->rx
= isis_recv_pdu_p2p
;
204 zlog_warn("isis_sock_init(): unknown circuit type");
205 retval
= ISIS_WARNING
;
213 static inline int llc_check(uint8_t *llc
)
215 if (*llc
!= ISO_SAP
|| *(llc
+ 1) != ISO_SAP
|| *(llc
+ 2) != 3)
221 int isis_recv_pdu_bcast(struct isis_circuit
*circuit
, uint8_t *ssnpa
)
223 int bytesread
, addr_len
;
224 struct sockaddr_ll s_addr
;
225 uint8_t llc
[LLC_LEN
];
227 addr_len
= sizeof(s_addr
);
229 memset(&s_addr
, 0, sizeof(struct sockaddr_ll
));
232 recvfrom(circuit
->fd
, (void *)&llc
, LLC_LEN
, MSG_PEEK
,
233 (struct sockaddr
*)&s_addr
, (socklen_t
*)&addr_len
);
236 || (s_addr
.sll_ifindex
!= (int)circuit
->interface
->ifindex
)) {
239 "isis_recv_packet_bcast(): ifname %s, fd %d, "
240 "bytesread %d, recvfrom(): %s",
241 circuit
->interface
->name
, circuit
->fd
,
242 bytesread
, safe_strerror(errno
));
244 if (s_addr
.sll_ifindex
!= (int)circuit
->interface
->ifindex
) {
246 "packet is received on multiple interfaces: "
247 "socket interface %d, circuit interface %d, "
249 s_addr
.sll_ifindex
, circuit
->interface
->ifindex
,
253 /* get rid of the packet */
254 bytesread
= recvfrom(circuit
->fd
, discard_buff
,
255 sizeof(discard_buff
), MSG_DONTWAIT
,
256 (struct sockaddr
*)&s_addr
,
257 (socklen_t
*)&addr_len
);
260 zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
265 * Filtering by llc field, discard packets sent by this host (other
268 if (!llc_check(llc
) || s_addr
.sll_pkttype
== PACKET_OUTGOING
) {
269 /* Read the packet into discard buff */
270 bytesread
= recvfrom(circuit
->fd
, discard_buff
,
271 sizeof(discard_buff
), MSG_DONTWAIT
,
272 (struct sockaddr
*)&s_addr
,
273 (socklen_t
*)&addr_len
);
275 zlog_warn("isis_recv_pdu_bcast(): recvfrom() failed");
279 /* Ensure that we have enough space for a pdu padded to fill the mtu */
280 unsigned int max_size
=
281 circuit
->interface
->mtu
> circuit
->interface
->mtu6
282 ? circuit
->interface
->mtu
283 : circuit
->interface
->mtu6
;
284 uint8_t temp_buff
[max_size
];
286 recvfrom(circuit
->fd
, temp_buff
, max_size
, MSG_DONTWAIT
,
287 (struct sockaddr
*)&s_addr
, (socklen_t
*)&addr_len
);
289 zlog_warn("%s: recvfrom() failed", __func__
);
292 /* then we lose the LLC */
293 stream_write(circuit
->rcv_stream
, temp_buff
+ LLC_LEN
,
294 bytesread
- LLC_LEN
);
295 memcpy(ssnpa
, &s_addr
.sll_addr
, s_addr
.sll_halen
);
300 int isis_recv_pdu_p2p(struct isis_circuit
*circuit
, uint8_t *ssnpa
)
302 int bytesread
, addr_len
;
303 struct sockaddr_ll s_addr
;
305 memset(&s_addr
, 0, sizeof(struct sockaddr_ll
));
306 addr_len
= sizeof(s_addr
);
308 /* we can read directly to the stream */
309 (void)stream_recvfrom(
310 circuit
->rcv_stream
, circuit
->fd
, circuit
->interface
->mtu
, 0,
311 (struct sockaddr
*)&s_addr
, (socklen_t
*)&addr_len
);
313 if (s_addr
.sll_pkttype
== PACKET_OUTGOING
) {
314 /* Read the packet into discard buff */
315 bytesread
= recvfrom(circuit
->fd
, discard_buff
,
316 sizeof(discard_buff
), MSG_DONTWAIT
,
317 (struct sockaddr
*)&s_addr
,
318 (socklen_t
*)&addr_len
);
320 zlog_warn("isis_recv_pdu_p2p(): recvfrom() failed");
324 /* If we don't have protocol type 0x00FE which is
325 * ISO over GRE we exit with pain :)
327 if (ntohs(s_addr
.sll_protocol
) != 0x00FE) {
328 zlog_warn("isis_recv_pdu_p2p(): protocol mismatch(): %X",
329 ntohs(s_addr
.sll_protocol
));
333 memcpy(ssnpa
, &s_addr
.sll_addr
, s_addr
.sll_halen
);
338 int isis_send_pdu_bcast(struct isis_circuit
*circuit
, int level
)
342 char temp_buff
[LLC_LEN
];
344 /* we need to do the LLC in here because of P2P circuits, which will
347 struct sockaddr_ll sa
;
349 stream_set_getp(circuit
->snd_stream
, 0);
350 memset(&sa
, 0, sizeof(struct sockaddr_ll
));
351 sa
.sll_family
= AF_PACKET
;
353 size_t frame_size
= stream_get_endp(circuit
->snd_stream
) + LLC_LEN
;
354 sa
.sll_protocol
= htons(isis_ethertype(frame_size
));
355 sa
.sll_ifindex
= circuit
->interface
->ifindex
;
356 sa
.sll_halen
= ETH_ALEN
;
357 /* RFC5309 section 4.1 recommends ALL_ISS */
358 if (circuit
->circ_type
== CIRCUIT_T_P2P
)
359 memcpy(&sa
.sll_addr
, ALL_ISS
, ETH_ALEN
);
361 memcpy(&sa
.sll_addr
, ALL_L1_ISS
, ETH_ALEN
);
363 memcpy(&sa
.sll_addr
, ALL_L2_ISS
, ETH_ALEN
);
365 /* on a broadcast circuit */
366 /* first we put the LLC in */
371 memset(&msg
, 0, sizeof(msg
));
373 msg
.msg_namelen
= sizeof(struct sockaddr_ll
);
376 iov
[0].iov_base
= temp_buff
;
377 iov
[0].iov_len
= LLC_LEN
;
378 iov
[1].iov_base
= circuit
->snd_stream
->data
;
379 iov
[1].iov_len
= stream_get_endp(circuit
->snd_stream
);
381 if (sendmsg(circuit
->fd
, &msg
, 0) < 0) {
382 zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
383 circuit
->interface
->name
, safe_strerror(errno
));
384 if (ERRNO_IO_RETRY(errno
))
391 int isis_send_pdu_p2p(struct isis_circuit
*circuit
, int level
)
393 struct sockaddr_ll sa
;
396 stream_set_getp(circuit
->snd_stream
, 0);
397 memset(&sa
, 0, sizeof(struct sockaddr_ll
));
398 sa
.sll_family
= AF_PACKET
;
399 sa
.sll_ifindex
= circuit
->interface
->ifindex
;
400 sa
.sll_halen
= ETH_ALEN
;
402 memcpy(&sa
.sll_addr
, ALL_L1_ISS
, ETH_ALEN
);
404 memcpy(&sa
.sll_addr
, ALL_L2_ISS
, ETH_ALEN
);
407 /* lets try correcting the protocol */
408 sa
.sll_protocol
= htons(0x00FE);
409 rv
= sendto(circuit
->fd
, circuit
->snd_stream
->data
,
410 stream_get_endp(circuit
->snd_stream
), 0,
411 (struct sockaddr
*)&sa
, sizeof(struct sockaddr_ll
));
413 zlog_warn("IS-IS pfpacket: could not transmit packet on %s: %s",
414 circuit
->interface
->name
, safe_strerror(errno
));
415 if (ERRNO_IO_RETRY(errno
))
422 #endif /* ISIS_METHOD == ISIS_METHOD_PFPACKET */