Commit | Line | Data |
---|---|---|
fba76a58 | 1 | // SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) |
465c0deb | 2 | /* gw.c - CAN frame Gateway/Router/Bridge with netlink interface |
c1aabdf3 | 3 | * |
456a8a64 | 4 | * Copyright (c) 2019 Volkswagen Group Electronic Research |
c1aabdf3 OH |
5 | * All rights reserved. |
6 | * | |
7 | * Redistribution and use in source and binary forms, with or without | |
8 | * modification, are permitted provided that the following conditions | |
9 | * are met: | |
10 | * 1. Redistributions of source code must retain the above copyright | |
11 | * notice, this list of conditions and the following disclaimer. | |
12 | * 2. Redistributions in binary form must reproduce the above copyright | |
13 | * notice, this list of conditions and the following disclaimer in the | |
14 | * documentation and/or other materials provided with the distribution. | |
15 | * 3. Neither the name of Volkswagen nor the names of its contributors | |
16 | * may be used to endorse or promote products derived from this software | |
17 | * without specific prior written permission. | |
18 | * | |
19 | * Alternatively, provided that this notice is retained in full, this | |
20 | * software may be distributed under the terms of the GNU General | |
21 | * Public License ("GPL") version 2, in which case the provisions of the | |
22 | * GPL apply INSTEAD OF those given above. | |
23 | * | |
24 | * The provided data structures and external interfaces from this code | |
25 | * are not restricted to be used by modules with a GPL compatible license. | |
26 | * | |
27 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |
28 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
29 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |
30 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | |
31 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
32 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | |
33 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
34 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
35 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
36 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
37 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH | |
38 | * DAMAGE. | |
39 | * | |
c1aabdf3 OH |
40 | */ |
41 | ||
42 | #include <linux/module.h> | |
43 | #include <linux/init.h> | |
44 | #include <linux/types.h> | |
be286baf | 45 | #include <linux/kernel.h> |
c1aabdf3 OH |
46 | #include <linux/list.h> |
47 | #include <linux/spinlock.h> | |
48 | #include <linux/rcupdate.h> | |
49 | #include <linux/rculist.h> | |
50 | #include <linux/net.h> | |
51 | #include <linux/netdevice.h> | |
52 | #include <linux/if_arp.h> | |
53 | #include <linux/skbuff.h> | |
54 | #include <linux/can.h> | |
55 | #include <linux/can/core.h> | |
d904d3ed | 56 | #include <linux/can/skb.h> |
c1aabdf3 OH |
57 | #include <linux/can/gw.h> |
58 | #include <net/rtnetlink.h> | |
59 | #include <net/net_namespace.h> | |
60 | #include <net/sock.h> | |
61 | ||
456a8a64 | 62 | #define CAN_GW_VERSION "20190810" |
be286baf | 63 | #define CAN_GW_NAME "can-gw" |
c1aabdf3 OH |
64 | |
65 | MODULE_DESCRIPTION("PF_CAN netlink gateway"); | |
66 | MODULE_LICENSE("Dual BSD/GPL"); | |
67 | MODULE_AUTHOR("Oliver Hartkopp <oliver.hartkopp@volkswagen.de>"); | |
be286baf OH |
68 | MODULE_ALIAS(CAN_GW_NAME); |
69 | ||
70 | #define CGW_MIN_HOPS 1 | |
71 | #define CGW_MAX_HOPS 6 | |
72 | #define CGW_DEFAULT_HOPS 1 | |
73 | ||
74 | static unsigned int max_hops __read_mostly = CGW_DEFAULT_HOPS; | |
d6444062 | 75 | module_param(max_hops, uint, 0444); |
be286baf OH |
76 | MODULE_PARM_DESC(max_hops, |
77 | "maximum " CAN_GW_NAME " routing hops for CAN frames " | |
78 | "(valid values: " __stringify(CGW_MIN_HOPS) "-" | |
79 | __stringify(CGW_MAX_HOPS) " hops, " | |
80 | "default: " __stringify(CGW_DEFAULT_HOPS) ")"); | |
c1aabdf3 | 81 | |
c1aabdf3 | 82 | static struct notifier_block notifier; |
c1aabdf3 OH |
83 | static struct kmem_cache *cgw_cache __read_mostly; |
84 | ||
85 | /* structure that contains the (on-the-fly) CAN frame modifications */ | |
86 | struct cf_mod { | |
87 | struct { | |
e9dc7c60 OH |
88 | struct canfd_frame and; |
89 | struct canfd_frame or; | |
90 | struct canfd_frame xor; | |
91 | struct canfd_frame set; | |
c1aabdf3 OH |
92 | } modframe; |
93 | struct { | |
94 | u8 and; | |
95 | u8 or; | |
96 | u8 xor; | |
97 | u8 set; | |
98 | } modtype; | |
e9dc7c60 | 99 | void (*modfunc[MAX_MODFUNCTIONS])(struct canfd_frame *cf, |
c1aabdf3 OH |
100 | struct cf_mod *mod); |
101 | ||
102 | /* CAN frame checksum calculation after CAN frame modifications */ | |
103 | struct { | |
104 | struct cgw_csum_xor xor; | |
105 | struct cgw_csum_crc8 crc8; | |
106 | } csum; | |
107 | struct { | |
e9dc7c60 OH |
108 | void (*xor)(struct canfd_frame *cf, |
109 | struct cgw_csum_xor *xor); | |
110 | void (*crc8)(struct canfd_frame *cf, | |
111 | struct cgw_csum_crc8 *crc8); | |
c1aabdf3 | 112 | } csumfunc; |
dd895d7f | 113 | u32 uid; |
c1aabdf3 OH |
114 | }; |
115 | ||
465c0deb | 116 | /* So far we just support CAN -> CAN routing and frame modifications. |
c1aabdf3 OH |
117 | * |
118 | * The internal can_can_gw structure contains data and attributes for | |
119 | * a CAN -> CAN gateway job. | |
120 | */ | |
121 | struct can_can_gw { | |
122 | struct can_filter filter; | |
123 | int src_idx; | |
124 | int dst_idx; | |
125 | }; | |
126 | ||
127 | /* list entry for CAN gateways jobs */ | |
128 | struct cgw_job { | |
129 | struct hlist_node list; | |
130 | struct rcu_head rcu; | |
131 | u32 handled_frames; | |
132 | u32 dropped_frames; | |
e6afa00a | 133 | u32 deleted_frames; |
c1aabdf3 OH |
134 | struct cf_mod mod; |
135 | union { | |
136 | /* CAN frame data source */ | |
137 | struct net_device *dev; | |
138 | } src; | |
139 | union { | |
140 | /* CAN frame data destination */ | |
141 | struct net_device *dev; | |
142 | } dst; | |
143 | union { | |
144 | struct can_can_gw ccgw; | |
145 | /* tbc */ | |
146 | }; | |
147 | u8 gwtype; | |
391ac128 | 148 | u8 limit_hops; |
c1aabdf3 OH |
149 | u16 flags; |
150 | }; | |
151 | ||
152 | /* modification functions that are invoked in the hot path in can_can_gw_rcv */ | |
153 | ||
e9dc7c60 | 154 | #define MODFUNC(func, op) static void func(struct canfd_frame *cf, \ |
c1aabdf3 OH |
155 | struct cf_mod *mod) { op ; } |
156 | ||
157 | MODFUNC(mod_and_id, cf->can_id &= mod->modframe.and.can_id) | |
e9dc7c60 | 158 | MODFUNC(mod_and_len, cf->len &= mod->modframe.and.len) |
456a8a64 | 159 | MODFUNC(mod_and_flags, cf->flags &= mod->modframe.and.flags) |
c1aabdf3 OH |
160 | MODFUNC(mod_and_data, *(u64 *)cf->data &= *(u64 *)mod->modframe.and.data) |
161 | MODFUNC(mod_or_id, cf->can_id |= mod->modframe.or.can_id) | |
e9dc7c60 | 162 | MODFUNC(mod_or_len, cf->len |= mod->modframe.or.len) |
456a8a64 | 163 | MODFUNC(mod_or_flags, cf->flags |= mod->modframe.or.flags) |
c1aabdf3 OH |
164 | MODFUNC(mod_or_data, *(u64 *)cf->data |= *(u64 *)mod->modframe.or.data) |
165 | MODFUNC(mod_xor_id, cf->can_id ^= mod->modframe.xor.can_id) | |
e9dc7c60 | 166 | MODFUNC(mod_xor_len, cf->len ^= mod->modframe.xor.len) |
456a8a64 | 167 | MODFUNC(mod_xor_flags, cf->flags ^= mod->modframe.xor.flags) |
c1aabdf3 OH |
168 | MODFUNC(mod_xor_data, *(u64 *)cf->data ^= *(u64 *)mod->modframe.xor.data) |
169 | MODFUNC(mod_set_id, cf->can_id = mod->modframe.set.can_id) | |
e9dc7c60 | 170 | MODFUNC(mod_set_len, cf->len = mod->modframe.set.len) |
456a8a64 | 171 | MODFUNC(mod_set_flags, cf->flags = mod->modframe.set.flags) |
c1aabdf3 OH |
172 | MODFUNC(mod_set_data, *(u64 *)cf->data = *(u64 *)mod->modframe.set.data) |
173 | ||
456a8a64 OH |
174 | static void mod_and_fddata(struct canfd_frame *cf, struct cf_mod *mod) |
175 | { | |
176 | int i; | |
177 | ||
178 | for (i = 0; i < CANFD_MAX_DLEN; i += 8) | |
179 | *(u64 *)(cf->data + i) &= *(u64 *)(mod->modframe.and.data + i); | |
180 | } | |
181 | ||
182 | static void mod_or_fddata(struct canfd_frame *cf, struct cf_mod *mod) | |
183 | { | |
184 | int i; | |
185 | ||
186 | for (i = 0; i < CANFD_MAX_DLEN; i += 8) | |
187 | *(u64 *)(cf->data + i) |= *(u64 *)(mod->modframe.or.data + i); | |
188 | } | |
189 | ||
190 | static void mod_xor_fddata(struct canfd_frame *cf, struct cf_mod *mod) | |
191 | { | |
192 | int i; | |
193 | ||
194 | for (i = 0; i < CANFD_MAX_DLEN; i += 8) | |
195 | *(u64 *)(cf->data + i) ^= *(u64 *)(mod->modframe.xor.data + i); | |
196 | } | |
197 | ||
198 | static void mod_set_fddata(struct canfd_frame *cf, struct cf_mod *mod) | |
199 | { | |
200 | memcpy(cf->data, mod->modframe.set.data, CANFD_MAX_DLEN); | |
201 | } | |
202 | ||
e9dc7c60 | 203 | static void canframecpy(struct canfd_frame *dst, struct can_frame *src) |
c1aabdf3 | 204 | { |
465c0deb | 205 | /* Copy the struct members separately to ensure that no uninitialized |
c1aabdf3 OH |
206 | * data are copied in the 3 bytes hole of the struct. This is needed |
207 | * to make easy compares of the data in the struct cf_mod. | |
208 | */ | |
209 | ||
210 | dst->can_id = src->can_id; | |
e9dc7c60 | 211 | dst->len = src->can_dlc; |
c1aabdf3 OH |
212 | *(u64 *)dst->data = *(u64 *)src->data; |
213 | } | |
214 | ||
456a8a64 OH |
215 | static void canfdframecpy(struct canfd_frame *dst, struct canfd_frame *src) |
216 | { | |
217 | /* Copy the struct members separately to ensure that no uninitialized | |
218 | * data are copied in the 2 bytes hole of the struct. This is needed | |
219 | * to make easy compares of the data in the struct cf_mod. | |
220 | */ | |
221 | ||
222 | dst->can_id = src->can_id; | |
223 | dst->flags = src->flags; | |
224 | dst->len = src->len; | |
225 | memcpy(dst->data, src->data, CANFD_MAX_DLEN); | |
226 | } | |
227 | ||
228 | static int cgw_chk_csum_parms(s8 fr, s8 to, s8 re, struct rtcanmsg *r) | |
c1aabdf3 | 229 | { |
e9dc7c60 OH |
230 | s8 dlen = CAN_MAX_DLEN; |
231 | ||
456a8a64 OH |
232 | if (r->flags & CGW_FLAGS_CAN_FD) |
233 | dlen = CANFD_MAX_DLEN; | |
234 | ||
465c0deb | 235 | /* absolute dlc values 0 .. 7 => 0 .. 7, e.g. data [0] |
c1aabdf3 OH |
236 | * relative to received dlc -1 .. -8 : |
237 | * e.g. for received dlc = 8 | |
238 | * -1 => index = 7 (data[7]) | |
239 | * -3 => index = 5 (data[5]) | |
240 | * -8 => index = 0 (data[0]) | |
241 | */ | |
242 | ||
e9dc7c60 OH |
243 | if (fr >= -dlen && fr < dlen && |
244 | to >= -dlen && to < dlen && | |
245 | re >= -dlen && re < dlen) | |
c1aabdf3 OH |
246 | return 0; |
247 | else | |
248 | return -EINVAL; | |
249 | } | |
250 | ||
e9dc7c60 | 251 | static inline int calc_idx(int idx, int rx_len) |
c1aabdf3 OH |
252 | { |
253 | if (idx < 0) | |
e9dc7c60 | 254 | return rx_len + idx; |
c1aabdf3 OH |
255 | else |
256 | return idx; | |
257 | } | |
258 | ||
e9dc7c60 | 259 | static void cgw_csum_xor_rel(struct canfd_frame *cf, struct cgw_csum_xor *xor) |
c1aabdf3 | 260 | { |
e9dc7c60 OH |
261 | int from = calc_idx(xor->from_idx, cf->len); |
262 | int to = calc_idx(xor->to_idx, cf->len); | |
263 | int res = calc_idx(xor->result_idx, cf->len); | |
c1aabdf3 OH |
264 | u8 val = xor->init_xor_val; |
265 | int i; | |
266 | ||
267 | if (from < 0 || to < 0 || res < 0) | |
268 | return; | |
269 | ||
270 | if (from <= to) { | |
271 | for (i = from; i <= to; i++) | |
272 | val ^= cf->data[i]; | |
273 | } else { | |
274 | for (i = from; i >= to; i--) | |
275 | val ^= cf->data[i]; | |
276 | } | |
277 | ||
278 | cf->data[res] = val; | |
279 | } | |
280 | ||
e9dc7c60 | 281 | static void cgw_csum_xor_pos(struct canfd_frame *cf, struct cgw_csum_xor *xor) |
c1aabdf3 OH |
282 | { |
283 | u8 val = xor->init_xor_val; | |
284 | int i; | |
285 | ||
286 | for (i = xor->from_idx; i <= xor->to_idx; i++) | |
287 | val ^= cf->data[i]; | |
288 | ||
289 | cf->data[xor->result_idx] = val; | |
290 | } | |
291 | ||
e9dc7c60 | 292 | static void cgw_csum_xor_neg(struct canfd_frame *cf, struct cgw_csum_xor *xor) |
c1aabdf3 OH |
293 | { |
294 | u8 val = xor->init_xor_val; | |
295 | int i; | |
296 | ||
297 | for (i = xor->from_idx; i >= xor->to_idx; i--) | |
298 | val ^= cf->data[i]; | |
299 | ||
300 | cf->data[xor->result_idx] = val; | |
301 | } | |
302 | ||
e9dc7c60 OH |
303 | static void cgw_csum_crc8_rel(struct canfd_frame *cf, |
304 | struct cgw_csum_crc8 *crc8) | |
c1aabdf3 | 305 | { |
e9dc7c60 OH |
306 | int from = calc_idx(crc8->from_idx, cf->len); |
307 | int to = calc_idx(crc8->to_idx, cf->len); | |
308 | int res = calc_idx(crc8->result_idx, cf->len); | |
c1aabdf3 OH |
309 | u8 crc = crc8->init_crc_val; |
310 | int i; | |
311 | ||
312 | if (from < 0 || to < 0 || res < 0) | |
313 | return; | |
314 | ||
315 | if (from <= to) { | |
316 | for (i = crc8->from_idx; i <= crc8->to_idx; i++) | |
5dfc8c94 | 317 | crc = crc8->crctab[crc ^ cf->data[i]]; |
c1aabdf3 OH |
318 | } else { |
319 | for (i = crc8->from_idx; i >= crc8->to_idx; i--) | |
5dfc8c94 | 320 | crc = crc8->crctab[crc ^ cf->data[i]]; |
c1aabdf3 OH |
321 | } |
322 | ||
323 | switch (crc8->profile) { | |
c1aabdf3 | 324 | case CGW_CRC8PRF_1U8: |
5dfc8c94 | 325 | crc = crc8->crctab[crc ^ crc8->profile_data[0]]; |
c1aabdf3 OH |
326 | break; |
327 | ||
328 | case CGW_CRC8PRF_16U8: | |
5dfc8c94 | 329 | crc = crc8->crctab[crc ^ crc8->profile_data[cf->data[1] & 0xF]]; |
c1aabdf3 OH |
330 | break; |
331 | ||
332 | case CGW_CRC8PRF_SFFID_XOR: | |
5dfc8c94 | 333 | crc = crc8->crctab[crc ^ (cf->can_id & 0xFF) ^ |
c1aabdf3 OH |
334 | (cf->can_id >> 8 & 0xFF)]; |
335 | break; | |
c1aabdf3 OH |
336 | } |
337 | ||
5dfc8c94 | 338 | cf->data[crc8->result_idx] = crc ^ crc8->final_xor_val; |
c1aabdf3 OH |
339 | } |
340 | ||
e9dc7c60 OH |
341 | static void cgw_csum_crc8_pos(struct canfd_frame *cf, |
342 | struct cgw_csum_crc8 *crc8) | |
c1aabdf3 OH |
343 | { |
344 | u8 crc = crc8->init_crc_val; | |
345 | int i; | |
346 | ||
347 | for (i = crc8->from_idx; i <= crc8->to_idx; i++) | |
5dfc8c94 | 348 | crc = crc8->crctab[crc ^ cf->data[i]]; |
c1aabdf3 OH |
349 | |
350 | switch (crc8->profile) { | |
c1aabdf3 | 351 | case CGW_CRC8PRF_1U8: |
5dfc8c94 | 352 | crc = crc8->crctab[crc ^ crc8->profile_data[0]]; |
c1aabdf3 OH |
353 | break; |
354 | ||
355 | case CGW_CRC8PRF_16U8: | |
5dfc8c94 | 356 | crc = crc8->crctab[crc ^ crc8->profile_data[cf->data[1] & 0xF]]; |
c1aabdf3 OH |
357 | break; |
358 | ||
359 | case CGW_CRC8PRF_SFFID_XOR: | |
5dfc8c94 | 360 | crc = crc8->crctab[crc ^ (cf->can_id & 0xFF) ^ |
c1aabdf3 OH |
361 | (cf->can_id >> 8 & 0xFF)]; |
362 | break; | |
363 | } | |
364 | ||
5dfc8c94 | 365 | cf->data[crc8->result_idx] = crc ^ crc8->final_xor_val; |
c1aabdf3 OH |
366 | } |
367 | ||
e9dc7c60 OH |
368 | static void cgw_csum_crc8_neg(struct canfd_frame *cf, |
369 | struct cgw_csum_crc8 *crc8) | |
c1aabdf3 OH |
370 | { |
371 | u8 crc = crc8->init_crc_val; | |
372 | int i; | |
373 | ||
374 | for (i = crc8->from_idx; i >= crc8->to_idx; i--) | |
5dfc8c94 | 375 | crc = crc8->crctab[crc ^ cf->data[i]]; |
c1aabdf3 OH |
376 | |
377 | switch (crc8->profile) { | |
c1aabdf3 | 378 | case CGW_CRC8PRF_1U8: |
5dfc8c94 | 379 | crc = crc8->crctab[crc ^ crc8->profile_data[0]]; |
c1aabdf3 OH |
380 | break; |
381 | ||
382 | case CGW_CRC8PRF_16U8: | |
5dfc8c94 | 383 | crc = crc8->crctab[crc ^ crc8->profile_data[cf->data[1] & 0xF]]; |
c1aabdf3 OH |
384 | break; |
385 | ||
386 | case CGW_CRC8PRF_SFFID_XOR: | |
5dfc8c94 | 387 | crc = crc8->crctab[crc ^ (cf->can_id & 0xFF) ^ |
c1aabdf3 OH |
388 | (cf->can_id >> 8 & 0xFF)]; |
389 | break; | |
390 | } | |
391 | ||
5dfc8c94 | 392 | cf->data[crc8->result_idx] = crc ^ crc8->final_xor_val; |
c1aabdf3 OH |
393 | } |
394 | ||
395 | /* the receive & process & send function */ | |
396 | static void can_can_gw_rcv(struct sk_buff *skb, void *data) | |
397 | { | |
398 | struct cgw_job *gwj = (struct cgw_job *)data; | |
e9dc7c60 | 399 | struct canfd_frame *cf; |
c1aabdf3 OH |
400 | struct sk_buff *nskb; |
401 | int modidx = 0; | |
402 | ||
456a8a64 OH |
403 | /* process strictly Classic CAN or CAN FD frames */ |
404 | if (gwj->flags & CGW_FLAGS_CAN_FD) { | |
405 | if (skb->len != CANFD_MTU) | |
406 | return; | |
407 | } else { | |
408 | if (skb->len != CAN_MTU) | |
409 | return; | |
410 | } | |
411 | ||
465c0deb | 412 | /* Do not handle CAN frames routed more than 'max_hops' times. |
be286baf OH |
413 | * In general we should never catch this delimiter which is intended |
414 | * to cover a misconfiguration protection (e.g. circular CAN routes). | |
415 | * | |
416 | * The Controller Area Network controllers only accept CAN frames with | |
417 | * correct CRCs - which are not visible in the controller registers. | |
418 | * According to skbuff.h documentation the csum_start element for IP | |
069f8457 | 419 | * checksums is undefined/unused when ip_summed == CHECKSUM_UNNECESSARY. |
be286baf OH |
420 | * Only CAN skbs can be processed here which already have this property. |
421 | */ | |
422 | ||
423 | #define cgw_hops(skb) ((skb)->csum_start) | |
424 | ||
425 | BUG_ON(skb->ip_summed != CHECKSUM_UNNECESSARY); | |
426 | ||
e6afa00a OH |
427 | if (cgw_hops(skb) >= max_hops) { |
428 | /* indicate deleted frames due to misconfiguration */ | |
429 | gwj->deleted_frames++; | |
c1aabdf3 | 430 | return; |
e6afa00a | 431 | } |
c1aabdf3 OH |
432 | |
433 | if (!(gwj->dst.dev->flags & IFF_UP)) { | |
434 | gwj->dropped_frames++; | |
435 | return; | |
436 | } | |
437 | ||
d904d3ed OH |
438 | /* is sending the skb back to the incoming interface not allowed? */ |
439 | if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) && | |
2bf3440d | 440 | can_skb_prv(skb)->ifindex == gwj->dst.dev->ifindex) |
d904d3ed OH |
441 | return; |
442 | ||
465c0deb | 443 | /* clone the given skb, which has not been done in can_rcv() |
c1aabdf3 OH |
444 | * |
445 | * When there is at least one modification function activated, | |
446 | * we need to copy the skb as we want to modify skb->data. | |
447 | */ | |
448 | if (gwj->mod.modfunc[0]) | |
449 | nskb = skb_copy(skb, GFP_ATOMIC); | |
450 | else | |
451 | nskb = skb_clone(skb, GFP_ATOMIC); | |
452 | ||
453 | if (!nskb) { | |
454 | gwj->dropped_frames++; | |
455 | return; | |
456 | } | |
457 | ||
be286baf OH |
458 | /* put the incremented hop counter in the cloned skb */ |
459 | cgw_hops(nskb) = cgw_hops(skb) + 1; | |
391ac128 OH |
460 | |
461 | /* first processing of this CAN frame -> adjust to private hop limit */ | |
462 | if (gwj->limit_hops && cgw_hops(nskb) == 1) | |
463 | cgw_hops(nskb) = max_hops - gwj->limit_hops + 1; | |
464 | ||
c1aabdf3 OH |
465 | nskb->dev = gwj->dst.dev; |
466 | ||
467 | /* pointer to modifiable CAN frame */ | |
e9dc7c60 | 468 | cf = (struct canfd_frame *)nskb->data; |
c1aabdf3 OH |
469 | |
470 | /* perform preprocessed modification functions if there are any */ | |
471 | while (modidx < MAX_MODFUNCTIONS && gwj->mod.modfunc[modidx]) | |
472 | (*gwj->mod.modfunc[modidx++])(cf, &gwj->mod); | |
473 | ||
0aaa8137 | 474 | /* Has the CAN frame been modified? */ |
c1aabdf3 | 475 | if (modidx) { |
0aaa8137 | 476 | /* get available space for the processed CAN frame type */ |
e9dc7c60 | 477 | int max_len = nskb->len - offsetof(struct canfd_frame, data); |
0aaa8137 OH |
478 | |
479 | /* dlc may have changed, make sure it fits to the CAN frame */ | |
456a8a64 OH |
480 | if (cf->len > max_len) { |
481 | /* delete frame due to misconfiguration */ | |
482 | gwj->deleted_frames++; | |
483 | kfree_skb(nskb); | |
484 | return; | |
0aaa8137 OH |
485 | } |
486 | ||
456a8a64 OH |
487 | /* check for checksum updates */ |
488 | if (gwj->mod.csumfunc.crc8) | |
489 | (*gwj->mod.csumfunc.crc8)(cf, &gwj->mod.csum.crc8); | |
c1aabdf3 | 490 | |
456a8a64 | 491 | if (gwj->mod.csumfunc.xor) |
c1aabdf3 OH |
492 | (*gwj->mod.csumfunc.xor)(cf, &gwj->mod.csum.xor); |
493 | } | |
494 | ||
495 | /* clear the skb timestamp if not configured the other way */ | |
496 | if (!(gwj->flags & CGW_FLAGS_CAN_SRC_TSTAMP)) | |
2456e855 | 497 | nskb->tstamp = 0; |
c1aabdf3 OH |
498 | |
499 | /* send to netdevice */ | |
500 | if (can_send(nskb, gwj->flags & CGW_FLAGS_CAN_ECHO)) | |
501 | gwj->dropped_frames++; | |
502 | else | |
503 | gwj->handled_frames++; | |
504 | } | |
505 | ||
1ef83310 | 506 | static inline int cgw_register_filter(struct net *net, struct cgw_job *gwj) |
c1aabdf3 | 507 | { |
1ef83310 | 508 | return can_rx_register(net, gwj->src.dev, gwj->ccgw.filter.can_id, |
c1aabdf3 | 509 | gwj->ccgw.filter.can_mask, can_can_gw_rcv, |
f1712c73 | 510 | gwj, "gw", NULL); |
c1aabdf3 OH |
511 | } |
512 | ||
1ef83310 | 513 | static inline void cgw_unregister_filter(struct net *net, struct cgw_job *gwj) |
c1aabdf3 | 514 | { |
1ef83310 | 515 | can_rx_unregister(net, gwj->src.dev, gwj->ccgw.filter.can_id, |
c1aabdf3 OH |
516 | gwj->ccgw.filter.can_mask, can_can_gw_rcv, gwj); |
517 | } | |
518 | ||
519 | static int cgw_notifier(struct notifier_block *nb, | |
351638e7 | 520 | unsigned long msg, void *ptr) |
c1aabdf3 | 521 | { |
351638e7 | 522 | struct net_device *dev = netdev_notifier_info_to_dev(ptr); |
1ef83310 | 523 | struct net *net = dev_net(dev); |
c1aabdf3 | 524 | |
c1aabdf3 OH |
525 | if (dev->type != ARPHRD_CAN) |
526 | return NOTIFY_DONE; | |
527 | ||
528 | if (msg == NETDEV_UNREGISTER) { | |
c1aabdf3 | 529 | struct cgw_job *gwj = NULL; |
b67bfe0d | 530 | struct hlist_node *nx; |
c1aabdf3 OH |
531 | |
532 | ASSERT_RTNL(); | |
533 | ||
1ef83310 | 534 | hlist_for_each_entry_safe(gwj, nx, &net->can.cgw_list, list) { |
c1aabdf3 OH |
535 | if (gwj->src.dev == dev || gwj->dst.dev == dev) { |
536 | hlist_del(&gwj->list); | |
1ef83310 | 537 | cgw_unregister_filter(net, gwj); |
3480a212 | 538 | kmem_cache_free(cgw_cache, gwj); |
c1aabdf3 OH |
539 | } |
540 | } | |
541 | } | |
542 | ||
543 | return NOTIFY_DONE; | |
544 | } | |
545 | ||
1da0faa3 TG |
546 | static int cgw_put_job(struct sk_buff *skb, struct cgw_job *gwj, int type, |
547 | u32 pid, u32 seq, int flags) | |
c1aabdf3 | 548 | { |
c1aabdf3 | 549 | struct rtcanmsg *rtcan; |
1da0faa3 TG |
550 | struct nlmsghdr *nlh; |
551 | ||
552 | nlh = nlmsg_put(skb, pid, seq, type, sizeof(*rtcan), flags); | |
c1aabdf3 OH |
553 | if (!nlh) |
554 | return -EMSGSIZE; | |
555 | ||
556 | rtcan = nlmsg_data(nlh); | |
557 | rtcan->can_family = AF_CAN; | |
558 | rtcan->gwtype = gwj->gwtype; | |
559 | rtcan->flags = gwj->flags; | |
560 | ||
561 | /* add statistics if available */ | |
562 | ||
563 | if (gwj->handled_frames) { | |
564 | if (nla_put_u32(skb, CGW_HANDLED, gwj->handled_frames) < 0) | |
565 | goto cancel; | |
c1aabdf3 OH |
566 | } |
567 | ||
568 | if (gwj->dropped_frames) { | |
569 | if (nla_put_u32(skb, CGW_DROPPED, gwj->dropped_frames) < 0) | |
570 | goto cancel; | |
c1aabdf3 OH |
571 | } |
572 | ||
e6afa00a OH |
573 | if (gwj->deleted_frames) { |
574 | if (nla_put_u32(skb, CGW_DELETED, gwj->deleted_frames) < 0) | |
575 | goto cancel; | |
576 | } | |
577 | ||
c1aabdf3 OH |
578 | /* check non default settings of attributes */ |
579 | ||
391ac128 OH |
580 | if (gwj->limit_hops) { |
581 | if (nla_put_u8(skb, CGW_LIM_HOPS, gwj->limit_hops) < 0) | |
582 | goto cancel; | |
583 | } | |
584 | ||
456a8a64 OH |
585 | if (gwj->flags & CGW_FLAGS_CAN_FD) { |
586 | struct cgw_fdframe_mod mb; | |
587 | ||
588 | if (gwj->mod.modtype.and) { | |
589 | memcpy(&mb.cf, &gwj->mod.modframe.and, sizeof(mb.cf)); | |
590 | mb.modtype = gwj->mod.modtype.and; | |
591 | if (nla_put(skb, CGW_FDMOD_AND, sizeof(mb), &mb) < 0) | |
592 | goto cancel; | |
593 | } | |
594 | ||
595 | if (gwj->mod.modtype.or) { | |
596 | memcpy(&mb.cf, &gwj->mod.modframe.or, sizeof(mb.cf)); | |
597 | mb.modtype = gwj->mod.modtype.or; | |
598 | if (nla_put(skb, CGW_FDMOD_OR, sizeof(mb), &mb) < 0) | |
599 | goto cancel; | |
600 | } | |
601 | ||
602 | if (gwj->mod.modtype.xor) { | |
603 | memcpy(&mb.cf, &gwj->mod.modframe.xor, sizeof(mb.cf)); | |
604 | mb.modtype = gwj->mod.modtype.xor; | |
605 | if (nla_put(skb, CGW_FDMOD_XOR, sizeof(mb), &mb) < 0) | |
606 | goto cancel; | |
607 | } | |
608 | ||
609 | if (gwj->mod.modtype.set) { | |
610 | memcpy(&mb.cf, &gwj->mod.modframe.set, sizeof(mb.cf)); | |
611 | mb.modtype = gwj->mod.modtype.set; | |
612 | if (nla_put(skb, CGW_FDMOD_SET, sizeof(mb), &mb) < 0) | |
613 | goto cancel; | |
614 | } | |
615 | } else { | |
e9dc7c60 | 616 | struct cgw_frame_mod mb; |
c1aabdf3 | 617 | |
e9dc7c60 OH |
618 | if (gwj->mod.modtype.and) { |
619 | memcpy(&mb.cf, &gwj->mod.modframe.and, sizeof(mb.cf)); | |
620 | mb.modtype = gwj->mod.modtype.and; | |
621 | if (nla_put(skb, CGW_MOD_AND, sizeof(mb), &mb) < 0) | |
622 | goto cancel; | |
623 | } | |
c1aabdf3 | 624 | |
e9dc7c60 OH |
625 | if (gwj->mod.modtype.or) { |
626 | memcpy(&mb.cf, &gwj->mod.modframe.or, sizeof(mb.cf)); | |
627 | mb.modtype = gwj->mod.modtype.or; | |
628 | if (nla_put(skb, CGW_MOD_OR, sizeof(mb), &mb) < 0) | |
629 | goto cancel; | |
630 | } | |
c1aabdf3 | 631 | |
e9dc7c60 OH |
632 | if (gwj->mod.modtype.xor) { |
633 | memcpy(&mb.cf, &gwj->mod.modframe.xor, sizeof(mb.cf)); | |
634 | mb.modtype = gwj->mod.modtype.xor; | |
635 | if (nla_put(skb, CGW_MOD_XOR, sizeof(mb), &mb) < 0) | |
636 | goto cancel; | |
637 | } | |
638 | ||
639 | if (gwj->mod.modtype.set) { | |
640 | memcpy(&mb.cf, &gwj->mod.modframe.set, sizeof(mb.cf)); | |
641 | mb.modtype = gwj->mod.modtype.set; | |
642 | if (nla_put(skb, CGW_MOD_SET, sizeof(mb), &mb) < 0) | |
643 | goto cancel; | |
644 | } | |
c1aabdf3 OH |
645 | } |
646 | ||
dd895d7f OH |
647 | if (gwj->mod.uid) { |
648 | if (nla_put_u32(skb, CGW_MOD_UID, gwj->mod.uid) < 0) | |
649 | goto cancel; | |
650 | } | |
651 | ||
c1aabdf3 OH |
652 | if (gwj->mod.csumfunc.crc8) { |
653 | if (nla_put(skb, CGW_CS_CRC8, CGW_CS_CRC8_LEN, | |
654 | &gwj->mod.csum.crc8) < 0) | |
655 | goto cancel; | |
c1aabdf3 OH |
656 | } |
657 | ||
658 | if (gwj->mod.csumfunc.xor) { | |
659 | if (nla_put(skb, CGW_CS_XOR, CGW_CS_XOR_LEN, | |
660 | &gwj->mod.csum.xor) < 0) | |
661 | goto cancel; | |
c1aabdf3 OH |
662 | } |
663 | ||
664 | if (gwj->gwtype == CGW_TYPE_CAN_CAN) { | |
c1aabdf3 OH |
665 | if (gwj->ccgw.filter.can_id || gwj->ccgw.filter.can_mask) { |
666 | if (nla_put(skb, CGW_FILTER, sizeof(struct can_filter), | |
667 | &gwj->ccgw.filter) < 0) | |
668 | goto cancel; | |
c1aabdf3 OH |
669 | } |
670 | ||
671 | if (nla_put_u32(skb, CGW_SRC_IF, gwj->ccgw.src_idx) < 0) | |
672 | goto cancel; | |
c1aabdf3 OH |
673 | |
674 | if (nla_put_u32(skb, CGW_DST_IF, gwj->ccgw.dst_idx) < 0) | |
675 | goto cancel; | |
c1aabdf3 OH |
676 | } |
677 | ||
053c095a JB |
678 | nlmsg_end(skb, nlh); |
679 | return 0; | |
c1aabdf3 OH |
680 | |
681 | cancel: | |
682 | nlmsg_cancel(skb, nlh); | |
683 | return -EMSGSIZE; | |
684 | } | |
685 | ||
686 | /* Dump information about all CAN gateway jobs, in response to RTM_GETROUTE */ | |
687 | static int cgw_dump_jobs(struct sk_buff *skb, struct netlink_callback *cb) | |
688 | { | |
1ef83310 | 689 | struct net *net = sock_net(skb->sk); |
c1aabdf3 | 690 | struct cgw_job *gwj = NULL; |
c1aabdf3 OH |
691 | int idx = 0; |
692 | int s_idx = cb->args[0]; | |
693 | ||
694 | rcu_read_lock(); | |
1ef83310 | 695 | hlist_for_each_entry_rcu(gwj, &net->can.cgw_list, list) { |
c1aabdf3 OH |
696 | if (idx < s_idx) |
697 | goto cont; | |
698 | ||
78f8a326 MKB |
699 | if (cgw_put_job(skb, gwj, RTM_NEWROUTE, |
700 | NETLINK_CB(cb->skb).portid, | |
701 | cb->nlh->nlmsg_seq, NLM_F_MULTI) < 0) | |
c1aabdf3 OH |
702 | break; |
703 | cont: | |
704 | idx++; | |
705 | } | |
706 | rcu_read_unlock(); | |
707 | ||
708 | cb->args[0] = idx; | |
709 | ||
710 | return skb->len; | |
711 | } | |
712 | ||
5dfc8c94 | 713 | static const struct nla_policy cgw_policy[CGW_MAX + 1] = { |
732d35fd TG |
714 | [CGW_MOD_AND] = { .len = sizeof(struct cgw_frame_mod) }, |
715 | [CGW_MOD_OR] = { .len = sizeof(struct cgw_frame_mod) }, | |
716 | [CGW_MOD_XOR] = { .len = sizeof(struct cgw_frame_mod) }, | |
717 | [CGW_MOD_SET] = { .len = sizeof(struct cgw_frame_mod) }, | |
718 | [CGW_CS_XOR] = { .len = sizeof(struct cgw_csum_xor) }, | |
719 | [CGW_CS_CRC8] = { .len = sizeof(struct cgw_csum_crc8) }, | |
720 | [CGW_SRC_IF] = { .type = NLA_U32 }, | |
721 | [CGW_DST_IF] = { .type = NLA_U32 }, | |
722 | [CGW_FILTER] = { .len = sizeof(struct can_filter) }, | |
391ac128 | 723 | [CGW_LIM_HOPS] = { .type = NLA_U8 }, |
dd895d7f | 724 | [CGW_MOD_UID] = { .type = NLA_U32 }, |
456a8a64 OH |
725 | [CGW_FDMOD_AND] = { .len = sizeof(struct cgw_fdframe_mod) }, |
726 | [CGW_FDMOD_OR] = { .len = sizeof(struct cgw_fdframe_mod) }, | |
727 | [CGW_FDMOD_XOR] = { .len = sizeof(struct cgw_fdframe_mod) }, | |
728 | [CGW_FDMOD_SET] = { .len = sizeof(struct cgw_fdframe_mod) }, | |
732d35fd TG |
729 | }; |
730 | ||
c1aabdf3 OH |
731 | /* check for common and gwtype specific attributes */ |
732 | static int cgw_parse_attr(struct nlmsghdr *nlh, struct cf_mod *mod, | |
391ac128 | 733 | u8 gwtype, void *gwtypeattr, u8 *limhops) |
c1aabdf3 | 734 | { |
5dfc8c94 | 735 | struct nlattr *tb[CGW_MAX + 1]; |
456a8a64 | 736 | struct rtcanmsg *r = nlmsg_data(nlh); |
c1aabdf3 OH |
737 | int modidx = 0; |
738 | int err = 0; | |
739 | ||
740 | /* initialize modification & checksum data space */ | |
741 | memset(mod, 0, sizeof(*mod)); | |
742 | ||
8cb08174 JB |
743 | err = nlmsg_parse_deprecated(nlh, sizeof(struct rtcanmsg), tb, |
744 | CGW_MAX, cgw_policy, NULL); | |
c1aabdf3 OH |
745 | if (err < 0) |
746 | return err; | |
747 | ||
391ac128 OH |
748 | if (tb[CGW_LIM_HOPS]) { |
749 | *limhops = nla_get_u8(tb[CGW_LIM_HOPS]); | |
750 | ||
751 | if (*limhops < 1 || *limhops > max_hops) | |
752 | return -EINVAL; | |
753 | } | |
754 | ||
c1aabdf3 | 755 | /* check for AND/OR/XOR/SET modifications */ |
456a8a64 OH |
756 | if (r->flags & CGW_FLAGS_CAN_FD) { |
757 | struct cgw_fdframe_mod mb; | |
758 | ||
759 | if (tb[CGW_FDMOD_AND]) { | |
760 | nla_memcpy(&mb, tb[CGW_FDMOD_AND], CGW_FDMODATTR_LEN); | |
761 | ||
762 | canfdframecpy(&mod->modframe.and, &mb.cf); | |
763 | mod->modtype.and = mb.modtype; | |
764 | ||
765 | if (mb.modtype & CGW_MOD_ID) | |
766 | mod->modfunc[modidx++] = mod_and_id; | |
767 | ||
768 | if (mb.modtype & CGW_MOD_LEN) | |
769 | mod->modfunc[modidx++] = mod_and_len; | |
770 | ||
771 | if (mb.modtype & CGW_MOD_FLAGS) | |
772 | mod->modfunc[modidx++] = mod_and_flags; | |
773 | ||
774 | if (mb.modtype & CGW_MOD_DATA) | |
775 | mod->modfunc[modidx++] = mod_and_fddata; | |
776 | } | |
777 | ||
778 | if (tb[CGW_FDMOD_OR]) { | |
779 | nla_memcpy(&mb, tb[CGW_FDMOD_OR], CGW_FDMODATTR_LEN); | |
780 | ||
781 | canfdframecpy(&mod->modframe.or, &mb.cf); | |
782 | mod->modtype.or = mb.modtype; | |
783 | ||
784 | if (mb.modtype & CGW_MOD_ID) | |
785 | mod->modfunc[modidx++] = mod_or_id; | |
786 | ||
787 | if (mb.modtype & CGW_MOD_LEN) | |
788 | mod->modfunc[modidx++] = mod_or_len; | |
789 | ||
790 | if (mb.modtype & CGW_MOD_FLAGS) | |
791 | mod->modfunc[modidx++] = mod_or_flags; | |
792 | ||
793 | if (mb.modtype & CGW_MOD_DATA) | |
794 | mod->modfunc[modidx++] = mod_or_fddata; | |
795 | } | |
796 | ||
797 | if (tb[CGW_FDMOD_XOR]) { | |
798 | nla_memcpy(&mb, tb[CGW_FDMOD_XOR], CGW_FDMODATTR_LEN); | |
799 | ||
800 | canfdframecpy(&mod->modframe.xor, &mb.cf); | |
801 | mod->modtype.xor = mb.modtype; | |
802 | ||
803 | if (mb.modtype & CGW_MOD_ID) | |
804 | mod->modfunc[modidx++] = mod_xor_id; | |
805 | ||
806 | if (mb.modtype & CGW_MOD_LEN) | |
807 | mod->modfunc[modidx++] = mod_xor_len; | |
808 | ||
809 | if (mb.modtype & CGW_MOD_FLAGS) | |
810 | mod->modfunc[modidx++] = mod_xor_flags; | |
811 | ||
812 | if (mb.modtype & CGW_MOD_DATA) | |
813 | mod->modfunc[modidx++] = mod_xor_fddata; | |
814 | } | |
815 | ||
816 | if (tb[CGW_FDMOD_SET]) { | |
817 | nla_memcpy(&mb, tb[CGW_FDMOD_SET], CGW_FDMODATTR_LEN); | |
818 | ||
819 | canfdframecpy(&mod->modframe.set, &mb.cf); | |
820 | mod->modtype.set = mb.modtype; | |
821 | ||
822 | if (mb.modtype & CGW_MOD_ID) | |
823 | mod->modfunc[modidx++] = mod_set_id; | |
824 | ||
825 | if (mb.modtype & CGW_MOD_LEN) | |
826 | mod->modfunc[modidx++] = mod_set_len; | |
827 | ||
828 | if (mb.modtype & CGW_MOD_FLAGS) | |
829 | mod->modfunc[modidx++] = mod_set_flags; | |
830 | ||
831 | if (mb.modtype & CGW_MOD_DATA) | |
832 | mod->modfunc[modidx++] = mod_set_fddata; | |
833 | } | |
834 | } else { | |
e9dc7c60 | 835 | struct cgw_frame_mod mb; |
c1aabdf3 | 836 | |
e9dc7c60 OH |
837 | if (tb[CGW_MOD_AND]) { |
838 | nla_memcpy(&mb, tb[CGW_MOD_AND], CGW_MODATTR_LEN); | |
c1aabdf3 | 839 | |
e9dc7c60 OH |
840 | canframecpy(&mod->modframe.and, &mb.cf); |
841 | mod->modtype.and = mb.modtype; | |
c1aabdf3 | 842 | |
e9dc7c60 OH |
843 | if (mb.modtype & CGW_MOD_ID) |
844 | mod->modfunc[modidx++] = mod_and_id; | |
c1aabdf3 | 845 | |
e9dc7c60 OH |
846 | if (mb.modtype & CGW_MOD_LEN) |
847 | mod->modfunc[modidx++] = mod_and_len; | |
c1aabdf3 | 848 | |
e9dc7c60 OH |
849 | if (mb.modtype & CGW_MOD_DATA) |
850 | mod->modfunc[modidx++] = mod_and_data; | |
851 | } | |
c1aabdf3 | 852 | |
e9dc7c60 OH |
853 | if (tb[CGW_MOD_OR]) { |
854 | nla_memcpy(&mb, tb[CGW_MOD_OR], CGW_MODATTR_LEN); | |
c1aabdf3 | 855 | |
e9dc7c60 OH |
856 | canframecpy(&mod->modframe.or, &mb.cf); |
857 | mod->modtype.or = mb.modtype; | |
c1aabdf3 | 858 | |
e9dc7c60 OH |
859 | if (mb.modtype & CGW_MOD_ID) |
860 | mod->modfunc[modidx++] = mod_or_id; | |
c1aabdf3 | 861 | |
e9dc7c60 OH |
862 | if (mb.modtype & CGW_MOD_LEN) |
863 | mod->modfunc[modidx++] = mod_or_len; | |
c1aabdf3 | 864 | |
e9dc7c60 OH |
865 | if (mb.modtype & CGW_MOD_DATA) |
866 | mod->modfunc[modidx++] = mod_or_data; | |
867 | } | |
c1aabdf3 | 868 | |
e9dc7c60 OH |
869 | if (tb[CGW_MOD_XOR]) { |
870 | nla_memcpy(&mb, tb[CGW_MOD_XOR], CGW_MODATTR_LEN); | |
c1aabdf3 | 871 | |
e9dc7c60 OH |
872 | canframecpy(&mod->modframe.xor, &mb.cf); |
873 | mod->modtype.xor = mb.modtype; | |
c1aabdf3 | 874 | |
e9dc7c60 OH |
875 | if (mb.modtype & CGW_MOD_ID) |
876 | mod->modfunc[modidx++] = mod_xor_id; | |
c1aabdf3 | 877 | |
e9dc7c60 OH |
878 | if (mb.modtype & CGW_MOD_LEN) |
879 | mod->modfunc[modidx++] = mod_xor_len; | |
c1aabdf3 | 880 | |
e9dc7c60 OH |
881 | if (mb.modtype & CGW_MOD_DATA) |
882 | mod->modfunc[modidx++] = mod_xor_data; | |
883 | } | |
c1aabdf3 | 884 | |
e9dc7c60 OH |
885 | if (tb[CGW_MOD_SET]) { |
886 | nla_memcpy(&mb, tb[CGW_MOD_SET], CGW_MODATTR_LEN); | |
c1aabdf3 | 887 | |
e9dc7c60 OH |
888 | canframecpy(&mod->modframe.set, &mb.cf); |
889 | mod->modtype.set = mb.modtype; | |
c1aabdf3 | 890 | |
e9dc7c60 OH |
891 | if (mb.modtype & CGW_MOD_ID) |
892 | mod->modfunc[modidx++] = mod_set_id; | |
c1aabdf3 | 893 | |
e9dc7c60 OH |
894 | if (mb.modtype & CGW_MOD_LEN) |
895 | mod->modfunc[modidx++] = mod_set_len; | |
c1aabdf3 | 896 | |
e9dc7c60 OH |
897 | if (mb.modtype & CGW_MOD_DATA) |
898 | mod->modfunc[modidx++] = mod_set_data; | |
899 | } | |
c1aabdf3 OH |
900 | } |
901 | ||
902 | /* check for checksum operations after CAN frame modifications */ | |
903 | if (modidx) { | |
732d35fd | 904 | if (tb[CGW_CS_CRC8]) { |
5d91efa8 | 905 | struct cgw_csum_crc8 *c = nla_data(tb[CGW_CS_CRC8]); |
c1aabdf3 OH |
906 | |
907 | err = cgw_chk_csum_parms(c->from_idx, c->to_idx, | |
456a8a64 | 908 | c->result_idx, r); |
c1aabdf3 OH |
909 | if (err) |
910 | return err; | |
911 | ||
912 | nla_memcpy(&mod->csum.crc8, tb[CGW_CS_CRC8], | |
913 | CGW_CS_CRC8_LEN); | |
914 | ||
465c0deb | 915 | /* select dedicated processing function to reduce |
c1aabdf3 OH |
916 | * runtime operations in receive hot path. |
917 | */ | |
918 | if (c->from_idx < 0 || c->to_idx < 0 || | |
919 | c->result_idx < 0) | |
920 | mod->csumfunc.crc8 = cgw_csum_crc8_rel; | |
921 | else if (c->from_idx <= c->to_idx) | |
922 | mod->csumfunc.crc8 = cgw_csum_crc8_pos; | |
923 | else | |
924 | mod->csumfunc.crc8 = cgw_csum_crc8_neg; | |
925 | } | |
926 | ||
732d35fd | 927 | if (tb[CGW_CS_XOR]) { |
5d91efa8 | 928 | struct cgw_csum_xor *c = nla_data(tb[CGW_CS_XOR]); |
c1aabdf3 OH |
929 | |
930 | err = cgw_chk_csum_parms(c->from_idx, c->to_idx, | |
456a8a64 | 931 | c->result_idx, r); |
c1aabdf3 OH |
932 | if (err) |
933 | return err; | |
934 | ||
935 | nla_memcpy(&mod->csum.xor, tb[CGW_CS_XOR], | |
936 | CGW_CS_XOR_LEN); | |
937 | ||
465c0deb | 938 | /* select dedicated processing function to reduce |
c1aabdf3 OH |
939 | * runtime operations in receive hot path. |
940 | */ | |
941 | if (c->from_idx < 0 || c->to_idx < 0 || | |
942 | c->result_idx < 0) | |
943 | mod->csumfunc.xor = cgw_csum_xor_rel; | |
944 | else if (c->from_idx <= c->to_idx) | |
945 | mod->csumfunc.xor = cgw_csum_xor_pos; | |
946 | else | |
947 | mod->csumfunc.xor = cgw_csum_xor_neg; | |
948 | } | |
dd895d7f | 949 | |
21468e6d | 950 | if (tb[CGW_MOD_UID]) |
dd895d7f | 951 | nla_memcpy(&mod->uid, tb[CGW_MOD_UID], sizeof(u32)); |
c1aabdf3 OH |
952 | } |
953 | ||
954 | if (gwtype == CGW_TYPE_CAN_CAN) { | |
c1aabdf3 | 955 | /* check CGW_TYPE_CAN_CAN specific attributes */ |
c1aabdf3 | 956 | struct can_can_gw *ccgw = (struct can_can_gw *)gwtypeattr; |
f62564f5 | 957 | |
c1aabdf3 OH |
958 | memset(ccgw, 0, sizeof(*ccgw)); |
959 | ||
960 | /* check for can_filter in attributes */ | |
732d35fd | 961 | if (tb[CGW_FILTER]) |
c1aabdf3 OH |
962 | nla_memcpy(&ccgw->filter, tb[CGW_FILTER], |
963 | sizeof(struct can_filter)); | |
964 | ||
965 | err = -ENODEV; | |
966 | ||
967 | /* specifying two interfaces is mandatory */ | |
968 | if (!tb[CGW_SRC_IF] || !tb[CGW_DST_IF]) | |
969 | return err; | |
970 | ||
732d35fd TG |
971 | ccgw->src_idx = nla_get_u32(tb[CGW_SRC_IF]); |
972 | ccgw->dst_idx = nla_get_u32(tb[CGW_DST_IF]); | |
c1aabdf3 OH |
973 | |
974 | /* both indices set to 0 for flushing all routing entries */ | |
975 | if (!ccgw->src_idx && !ccgw->dst_idx) | |
976 | return 0; | |
977 | ||
978 | /* only one index set to 0 is an error */ | |
979 | if (!ccgw->src_idx || !ccgw->dst_idx) | |
980 | return err; | |
981 | } | |
982 | ||
983 | /* add the checks for other gwtypes here */ | |
984 | ||
985 | return 0; | |
986 | } | |
987 | ||
c21ef3e3 DA |
988 | static int cgw_create_job(struct sk_buff *skb, struct nlmsghdr *nlh, |
989 | struct netlink_ext_ack *extack) | |
c1aabdf3 | 990 | { |
1ef83310 | 991 | struct net *net = sock_net(skb->sk); |
c1aabdf3 OH |
992 | struct rtcanmsg *r; |
993 | struct cgw_job *gwj; | |
dd895d7f OH |
994 | struct cf_mod mod; |
995 | struct can_can_gw ccgw; | |
391ac128 | 996 | u8 limhops = 0; |
c1aabdf3 OH |
997 | int err = 0; |
998 | ||
90f62cf3 | 999 | if (!netlink_capable(skb, CAP_NET_ADMIN)) |
dfc47ef8 EB |
1000 | return -EPERM; |
1001 | ||
c1aabdf3 OH |
1002 | if (nlmsg_len(nlh) < sizeof(*r)) |
1003 | return -EINVAL; | |
1004 | ||
1005 | r = nlmsg_data(nlh); | |
1006 | if (r->can_family != AF_CAN) | |
1007 | return -EPFNOSUPPORT; | |
1008 | ||
1009 | /* so far we only support CAN -> CAN routings */ | |
1010 | if (r->gwtype != CGW_TYPE_CAN_CAN) | |
1011 | return -EINVAL; | |
1012 | ||
dd895d7f OH |
1013 | err = cgw_parse_attr(nlh, &mod, CGW_TYPE_CAN_CAN, &ccgw, &limhops); |
1014 | if (err < 0) | |
1015 | return err; | |
1016 | ||
1017 | if (mod.uid) { | |
dd895d7f OH |
1018 | ASSERT_RTNL(); |
1019 | ||
1020 | /* check for updating an existing job with identical uid */ | |
1ef83310 | 1021 | hlist_for_each_entry(gwj, &net->can.cgw_list, list) { |
dd895d7f OH |
1022 | if (gwj->mod.uid != mod.uid) |
1023 | continue; | |
1024 | ||
1025 | /* interfaces & filters must be identical */ | |
1026 | if (memcmp(&gwj->ccgw, &ccgw, sizeof(ccgw))) | |
1027 | return -EINVAL; | |
1028 | ||
1029 | /* update modifications with disabled softirq & quit */ | |
1030 | local_bh_disable(); | |
1031 | memcpy(&gwj->mod, &mod, sizeof(mod)); | |
1032 | local_bh_enable(); | |
1033 | return 0; | |
1034 | } | |
1035 | } | |
1036 | ||
1037 | /* ifindex == 0 is not allowed for job creation */ | |
1038 | if (!ccgw.src_idx || !ccgw.dst_idx) | |
1039 | return -ENODEV; | |
1040 | ||
c1aabdf3 OH |
1041 | gwj = kmem_cache_alloc(cgw_cache, GFP_KERNEL); |
1042 | if (!gwj) | |
1043 | return -ENOMEM; | |
1044 | ||
1045 | gwj->handled_frames = 0; | |
1046 | gwj->dropped_frames = 0; | |
e6afa00a | 1047 | gwj->deleted_frames = 0; |
c1aabdf3 OH |
1048 | gwj->flags = r->flags; |
1049 | gwj->gwtype = r->gwtype; | |
dd895d7f | 1050 | gwj->limit_hops = limhops; |
c1aabdf3 | 1051 | |
dd895d7f OH |
1052 | /* insert already parsed information */ |
1053 | memcpy(&gwj->mod, &mod, sizeof(mod)); | |
1054 | memcpy(&gwj->ccgw, &ccgw, sizeof(ccgw)); | |
c1aabdf3 OH |
1055 | |
1056 | err = -ENODEV; | |
1057 | ||
1ef83310 | 1058 | gwj->src.dev = __dev_get_by_index(net, gwj->ccgw.src_idx); |
c1aabdf3 OH |
1059 | |
1060 | if (!gwj->src.dev) | |
1061 | goto out; | |
1062 | ||
c0ebbdd6 | 1063 | if (gwj->src.dev->type != ARPHRD_CAN) |
5af28de3 | 1064 | goto out; |
c1aabdf3 | 1065 | |
1ef83310 | 1066 | gwj->dst.dev = __dev_get_by_index(net, gwj->ccgw.dst_idx); |
c1aabdf3 OH |
1067 | |
1068 | if (!gwj->dst.dev) | |
5af28de3 | 1069 | goto out; |
c1aabdf3 | 1070 | |
c0ebbdd6 | 1071 | if (gwj->dst.dev->type != ARPHRD_CAN) |
5af28de3 | 1072 | goto out; |
c1aabdf3 OH |
1073 | |
1074 | ASSERT_RTNL(); | |
1075 | ||
1ef83310 | 1076 | err = cgw_register_filter(net, gwj); |
c1aabdf3 | 1077 | if (!err) |
1ef83310 | 1078 | hlist_add_head_rcu(&gwj->list, &net->can.cgw_list); |
c1aabdf3 OH |
1079 | out: |
1080 | if (err) | |
1081 | kmem_cache_free(cgw_cache, gwj); | |
1082 | ||
1083 | return err; | |
1084 | } | |
1085 | ||
1ef83310 | 1086 | static void cgw_remove_all_jobs(struct net *net) |
c1aabdf3 OH |
1087 | { |
1088 | struct cgw_job *gwj = NULL; | |
b67bfe0d | 1089 | struct hlist_node *nx; |
c1aabdf3 OH |
1090 | |
1091 | ASSERT_RTNL(); | |
1092 | ||
1ef83310 | 1093 | hlist_for_each_entry_safe(gwj, nx, &net->can.cgw_list, list) { |
c1aabdf3 | 1094 | hlist_del(&gwj->list); |
1ef83310 | 1095 | cgw_unregister_filter(net, gwj); |
3480a212 | 1096 | kmem_cache_free(cgw_cache, gwj); |
c1aabdf3 OH |
1097 | } |
1098 | } | |
1099 | ||
c21ef3e3 DA |
1100 | static int cgw_remove_job(struct sk_buff *skb, struct nlmsghdr *nlh, |
1101 | struct netlink_ext_ack *extack) | |
c1aabdf3 | 1102 | { |
1ef83310 | 1103 | struct net *net = sock_net(skb->sk); |
c1aabdf3 | 1104 | struct cgw_job *gwj = NULL; |
b67bfe0d | 1105 | struct hlist_node *nx; |
c1aabdf3 OH |
1106 | struct rtcanmsg *r; |
1107 | struct cf_mod mod; | |
1108 | struct can_can_gw ccgw; | |
391ac128 | 1109 | u8 limhops = 0; |
c1aabdf3 OH |
1110 | int err = 0; |
1111 | ||
90f62cf3 | 1112 | if (!netlink_capable(skb, CAP_NET_ADMIN)) |
dfc47ef8 EB |
1113 | return -EPERM; |
1114 | ||
c1aabdf3 OH |
1115 | if (nlmsg_len(nlh) < sizeof(*r)) |
1116 | return -EINVAL; | |
1117 | ||
1118 | r = nlmsg_data(nlh); | |
1119 | if (r->can_family != AF_CAN) | |
1120 | return -EPFNOSUPPORT; | |
1121 | ||
1122 | /* so far we only support CAN -> CAN routings */ | |
1123 | if (r->gwtype != CGW_TYPE_CAN_CAN) | |
1124 | return -EINVAL; | |
1125 | ||
391ac128 | 1126 | err = cgw_parse_attr(nlh, &mod, CGW_TYPE_CAN_CAN, &ccgw, &limhops); |
c1aabdf3 OH |
1127 | if (err < 0) |
1128 | return err; | |
1129 | ||
1130 | /* two interface indices both set to 0 => remove all entries */ | |
1131 | if (!ccgw.src_idx && !ccgw.dst_idx) { | |
1ef83310 | 1132 | cgw_remove_all_jobs(net); |
c1aabdf3 OH |
1133 | return 0; |
1134 | } | |
1135 | ||
1136 | err = -EINVAL; | |
1137 | ||
1138 | ASSERT_RTNL(); | |
1139 | ||
1140 | /* remove only the first matching entry */ | |
1ef83310 | 1141 | hlist_for_each_entry_safe(gwj, nx, &net->can.cgw_list, list) { |
c1aabdf3 OH |
1142 | if (gwj->flags != r->flags) |
1143 | continue; | |
1144 | ||
391ac128 OH |
1145 | if (gwj->limit_hops != limhops) |
1146 | continue; | |
1147 | ||
dd895d7f OH |
1148 | /* we have a match when uid is enabled and identical */ |
1149 | if (gwj->mod.uid || mod.uid) { | |
1150 | if (gwj->mod.uid != mod.uid) | |
1151 | continue; | |
1152 | } else { | |
1153 | /* no uid => check for identical modifications */ | |
1154 | if (memcmp(&gwj->mod, &mod, sizeof(mod))) | |
1155 | continue; | |
1156 | } | |
c1aabdf3 OH |
1157 | |
1158 | /* if (r->gwtype == CGW_TYPE_CAN_CAN) - is made sure here */ | |
1159 | if (memcmp(&gwj->ccgw, &ccgw, sizeof(ccgw))) | |
1160 | continue; | |
1161 | ||
1162 | hlist_del(&gwj->list); | |
1ef83310 | 1163 | cgw_unregister_filter(net, gwj); |
3480a212 | 1164 | kmem_cache_free(cgw_cache, gwj); |
c1aabdf3 OH |
1165 | err = 0; |
1166 | break; | |
1167 | } | |
1168 | ||
1169 | return err; | |
1170 | } | |
1171 | ||
1ef83310 OH |
1172 | static int __net_init cangw_pernet_init(struct net *net) |
1173 | { | |
1174 | INIT_HLIST_HEAD(&net->can.cgw_list); | |
1175 | return 0; | |
1176 | } | |
1177 | ||
1178 | static void __net_exit cangw_pernet_exit(struct net *net) | |
1179 | { | |
1180 | rtnl_lock(); | |
1181 | cgw_remove_all_jobs(net); | |
1182 | rtnl_unlock(); | |
1183 | } | |
1184 | ||
1185 | static struct pernet_operations cangw_pernet_ops = { | |
1186 | .init = cangw_pernet_init, | |
1187 | .exit = cangw_pernet_exit, | |
1188 | }; | |
1189 | ||
c1aabdf3 OH |
1190 | static __init int cgw_module_init(void) |
1191 | { | |
c1c502b5 FW |
1192 | int ret; |
1193 | ||
be286baf OH |
1194 | /* sanitize given module parameter */ |
1195 | max_hops = clamp_t(unsigned int, max_hops, CGW_MIN_HOPS, CGW_MAX_HOPS); | |
1196 | ||
1197 | pr_info("can: netlink gateway (rev " CAN_GW_VERSION ") max_hops=%d\n", | |
1198 | max_hops); | |
c1aabdf3 | 1199 | |
b7a14297 Y |
1200 | ret = register_pernet_subsys(&cangw_pernet_ops); |
1201 | if (ret) | |
1202 | return ret; | |
1203 | ||
1204 | ret = -ENOMEM; | |
c1aabdf3 OH |
1205 | cgw_cache = kmem_cache_create("can_gw", sizeof(struct cgw_job), |
1206 | 0, 0, NULL); | |
c1aabdf3 | 1207 | if (!cgw_cache) |
b7a14297 | 1208 | goto out_cache_create; |
c1aabdf3 OH |
1209 | |
1210 | /* set notifier */ | |
1211 | notifier.notifier_call = cgw_notifier; | |
b7a14297 Y |
1212 | ret = register_netdevice_notifier(¬ifier); |
1213 | if (ret) | |
1214 | goto out_register_notifier; | |
c1aabdf3 | 1215 | |
c1c502b5 FW |
1216 | ret = rtnl_register_module(THIS_MODULE, PF_CAN, RTM_GETROUTE, |
1217 | NULL, cgw_dump_jobs, 0); | |
b7a14297 Y |
1218 | if (ret) |
1219 | goto out_rtnl_register1; | |
1220 | ||
1221 | ret = rtnl_register_module(THIS_MODULE, PF_CAN, RTM_NEWROUTE, | |
1222 | cgw_create_job, NULL, 0); | |
1223 | if (ret) | |
1224 | goto out_rtnl_register2; | |
1225 | ret = rtnl_register_module(THIS_MODULE, PF_CAN, RTM_DELROUTE, | |
1226 | cgw_remove_job, NULL, 0); | |
1227 | if (ret) | |
1228 | goto out_rtnl_register3; | |
c1aabdf3 OH |
1229 | |
1230 | return 0; | |
b7a14297 Y |
1231 | |
1232 | out_rtnl_register3: | |
1233 | rtnl_unregister(PF_CAN, RTM_NEWROUTE); | |
1234 | out_rtnl_register2: | |
1235 | rtnl_unregister(PF_CAN, RTM_GETROUTE); | |
1236 | out_rtnl_register1: | |
1237 | unregister_netdevice_notifier(¬ifier); | |
1238 | out_register_notifier: | |
1239 | kmem_cache_destroy(cgw_cache); | |
1240 | out_cache_create: | |
1241 | unregister_pernet_subsys(&cangw_pernet_ops); | |
1242 | ||
1243 | return ret; | |
c1aabdf3 OH |
1244 | } |
1245 | ||
1246 | static __exit void cgw_module_exit(void) | |
1247 | { | |
1248 | rtnl_unregister_all(PF_CAN); | |
1249 | ||
1250 | unregister_netdevice_notifier(¬ifier); | |
1251 | ||
1ef83310 | 1252 | unregister_pernet_subsys(&cangw_pernet_ops); |
c1aabdf3 OH |
1253 | rcu_barrier(); /* Wait for completion of call_rcu()'s */ |
1254 | ||
1255 | kmem_cache_destroy(cgw_cache); | |
1256 | } | |
1257 | ||
1258 | module_init(cgw_module_init); | |
1259 | module_exit(cgw_module_exit); |