1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
5 * Copyright (c) 1980, 1986, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 #include <sys/param.h>
34 #include <sys/eventhandler.h>
35 #include <sys/malloc.h>
36 #include <sys/limits.h>
37 #include <sys/lock.h>
38 #include <sys/mutex.h>
39 #include <sys/kernel.h>
40 #include <sys/systm.h>
41 #include <sys/types.h>
42 #include <sys/socket.h>
43
44 #include <net/if.h>
45 #include <net/if_var.h>
46 #include <net/if_private.h>
47 #include <net/if_clone.h>
48 #include <net/radix.h>
49 #include <net/route.h>
50 #include <net/vnet.h>
51
52 #include <netlink/netlink.h>
53 #include <netlink/netlink_ctl.h>
54 #include <netlink/netlink_route.h>
55 #include <netlink/route/route_var.h>
56
57 /* Current IF_MAXUNIT expands maximum to 5 characters. */
58 #define IFCLOSIZ (IFNAMSIZ - 5)
59
60 /*
61 * Structure describing a `cloning' interface.
62 *
63 * List of locks
64 * (c) const until freeing
65 * (d) driver specific data, may need external protection.
66 * (e) locked by if_cloners_mtx
67 * (i) locked by ifc_mtx mtx
68 */
69 struct if_clone {
70 char ifc_name[IFCLOSIZ]; /* (c) Name of device, e.g. `gif' */
71 struct unrhdr *ifc_unrhdr; /* (c) alloc_unr(9) header */
72 int ifc_maxunit; /* (c) maximum unit number */
73 int ifc_flags;
74 long ifc_refcnt; /* (i) Reference count. */
75 LIST_HEAD(, ifnet) ifc_iflist; /* (i) List of cloned interfaces */
76 struct mtx ifc_mtx; /* Mutex to protect members. */
77
78 ifc_match_f *ifc_match; /* (c) Matcher function */
79 ifc_create_f *ifc_create; /* (c) Creates new interface */
80 ifc_destroy_f *ifc_destroy; /* (c) Destroys cloned interface */
81
82 ifc_create_nl_f *create_nl; /* (c) Netlink creation handler */
83 ifc_modify_nl_f *modify_nl; /* (c) Netlink modification handler */
84 ifc_dump_nl_f *dump_nl; /* (c) Netlink dump handler */
85
86 #ifdef CLONE_COMPAT_13
87 /* (c) Driver specific cloning functions. Called with no locks held. */
88 union {
89 struct { /* advanced cloner */
90 ifc_create_t *_ifc_create;
91 ifc_destroy_t *_ifc_destroy;
92 } A;
93 struct { /* simple cloner */
94 ifcs_create_t *_ifcs_create;
95 ifcs_destroy_t *_ifcs_destroy;
96 int _ifcs_minifs; /* minimum ifs */
97
98 } S;
99 } U;
100 #define ifca_create U.A._ifc_create
101 #define ifca_destroy U.A._ifc_destroy
102 #define ifcs_create U.S._ifcs_create
103 #define ifcs_destroy U.S._ifcs_destroy
104 #define ifcs_minifs U.S._ifcs_minifs
105 #endif
106
107 LIST_ENTRY(if_clone) ifc_list; /* (e) On list of cloners */
108 };
109
110
111
112 static void if_clone_free(struct if_clone *ifc);
113 static int if_clone_createif_nl(struct if_clone *ifc, const char *name,
114 struct ifc_data_nl *ifd);
115
116 static int ifc_simple_match(struct if_clone *ifc, const char *name);
117 static int ifc_handle_unit(struct if_clone *ifc, char *name, size_t len, int *punit);
118 static struct if_clone *ifc_find_cloner(const char *name);
119 static struct if_clone *ifc_find_cloner_match(const char *name);
120
121 #ifdef CLONE_COMPAT_13
122 static int ifc_simple_create_wrapper(struct if_clone *ifc, char *name, size_t maxlen,
123 struct ifc_data *ifc_data, struct ifnet **ifpp);
124 static int ifc_advanced_create_wrapper(struct if_clone *ifc, char *name, size_t maxlen,
125 struct ifc_data *ifc_data, struct ifnet **ifpp);
126 #endif
127
128 static struct mtx if_cloners_mtx;
129 MTX_SYSINIT(if_cloners_lock, &if_cloners_mtx, "if_cloners lock", MTX_DEF);
130 VNET_DEFINE_STATIC(int, if_cloners_count);
131 VNET_DEFINE(LIST_HEAD(, if_clone), if_cloners);
132
133 #define V_if_cloners_count VNET(if_cloners_count)
134 #define V_if_cloners VNET(if_cloners)
135
136 #define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED)
137 #define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx)
138 #define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx)
139
140 #define IF_CLONE_LOCK_INIT(ifc) \
141 mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF)
142 #define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx)
143 #define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED)
144 #define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx)
145 #define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx)
146
147 #define IF_CLONE_ADDREF(ifc) \
148 do { \
149 IF_CLONE_LOCK(ifc); \
150 IF_CLONE_ADDREF_LOCKED(ifc); \
151 IF_CLONE_UNLOCK(ifc); \
152 } while (0)
153 #define IF_CLONE_ADDREF_LOCKED(ifc) \
154 do { \
155 IF_CLONE_LOCK_ASSERT(ifc); \
156 KASSERT((ifc)->ifc_refcnt >= 0, \
157 ("negative refcnt %ld", (ifc)->ifc_refcnt)); \
158 (ifc)->ifc_refcnt++; \
159 } while (0)
160 #define IF_CLONE_REMREF(ifc) \
161 do { \
162 IF_CLONE_LOCK(ifc); \
163 IF_CLONE_REMREF_LOCKED(ifc); \
164 } while (0)
165 #define IF_CLONE_REMREF_LOCKED(ifc) \
166 do { \
167 IF_CLONE_LOCK_ASSERT(ifc); \
168 KASSERT((ifc)->ifc_refcnt > 0, \
169 ("bogus refcnt %ld", (ifc)->ifc_refcnt)); \
170 if (--(ifc)->ifc_refcnt == 0) { \
171 IF_CLONE_UNLOCK(ifc); \
172 if_clone_free(ifc); \
173 } else { \
174 /* silently free the lock */ \
175 IF_CLONE_UNLOCK(ifc); \
176 } \
177 } while (0)
178
179 #define IFC_IFLIST_INSERT(_ifc, _ifp) \
180 LIST_INSERT_HEAD(&_ifc->ifc_iflist, _ifp, if_clones)
181 #define IFC_IFLIST_REMOVE(_ifc, _ifp) \
182 LIST_REMOVE(_ifp, if_clones)
183
184 static MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
185
186 void
vnet_if_clone_init(void)187 vnet_if_clone_init(void)
188 {
189
190 LIST_INIT(&V_if_cloners);
191 }
192
193 /*
194 * Lookup and create a clone network interface.
195 */
196 int
ifc_create_ifp(const char * name,struct ifc_data * ifd,struct ifnet ** ifpp)197 ifc_create_ifp(const char *name, struct ifc_data *ifd, struct ifnet **ifpp)
198 {
199 struct if_clone *ifc = ifc_find_cloner_match(name);
200
201 if (ifc == NULL)
202 return (EINVAL);
203
204 struct ifc_data_nl ifd_new = {
205 .flags = ifd->flags,
206 .unit = ifd->unit,
207 .params = ifd->params,
208 };
209
210 int error = if_clone_createif_nl(ifc, name, &ifd_new);
211
212 if (ifpp != NULL)
213 *ifpp = ifd_new.ifp;
214
215 return (error);
216 }
217
218 bool
ifc_create_ifp_nl(const char * name,struct ifc_data_nl * ifd)219 ifc_create_ifp_nl(const char *name, struct ifc_data_nl *ifd)
220 {
221 struct if_clone *ifc = ifc_find_cloner_match(name);
222 if (ifc == NULL) {
223 ifd->error = EINVAL;
224 return (false);
225 }
226
227 ifd->error = if_clone_createif_nl(ifc, name, ifd);
228
229 return (true);
230 }
231
232 int
if_clone_create(char * name,size_t len,caddr_t params)233 if_clone_create(char *name, size_t len, caddr_t params)
234 {
235 struct ifc_data ifd = { .params = params };
236 struct ifnet *ifp;
237
238 int error = ifc_create_ifp(name, &ifd, &ifp);
239
240 if (error == 0)
241 strlcpy(name, if_name(ifp), len);
242
243 return (error);
244 }
245
246 bool
ifc_modify_ifp_nl(struct ifnet * ifp,struct ifc_data_nl * ifd)247 ifc_modify_ifp_nl(struct ifnet *ifp, struct ifc_data_nl *ifd)
248 {
249 struct if_clone *ifc = ifc_find_cloner(ifp->if_dname);
250 if (ifc == NULL) {
251 ifd->error = EINVAL;
252 return (false);
253 }
254
255 ifd->error = (*ifc->modify_nl)(ifp, ifd);
256 return (true);
257 }
258
259 bool
ifc_dump_ifp_nl(struct ifnet * ifp,struct nl_writer * nw)260 ifc_dump_ifp_nl(struct ifnet *ifp, struct nl_writer *nw)
261 {
262 struct if_clone *ifc = ifc_find_cloner(ifp->if_dname);
263 if (ifc == NULL)
264 return (false);
265
266 (*ifc->dump_nl)(ifp, nw);
267 return (true);
268 }
269
270 static int
ifc_create_ifp_nl_default(struct if_clone * ifc,char * name,size_t len,struct ifc_data_nl * ifd)271 ifc_create_ifp_nl_default(struct if_clone *ifc, char *name, size_t len,
272 struct ifc_data_nl *ifd)
273 {
274 struct ifc_data ifd_new = {
275 .flags = ifd->flags,
276 .unit = ifd->unit,
277 .params = ifd->params,
278 };
279
280 return ((*ifc->ifc_create)(ifc, name, len, &ifd_new, &ifd->ifp));
281 }
282
283 static int
ifc_modify_ifp_nl_default(struct ifnet * ifp,struct ifc_data_nl * ifd)284 ifc_modify_ifp_nl_default(struct ifnet *ifp, struct ifc_data_nl *ifd)
285 {
286 if (ifd->lattrs != NULL)
287 return (nl_modify_ifp_generic(ifp, ifd->lattrs, ifd->bm, ifd->npt));
288 return (0);
289 }
290
291 static void
ifc_dump_ifp_nl_default(struct ifnet * ifp,struct nl_writer * nw)292 ifc_dump_ifp_nl_default(struct ifnet *ifp, struct nl_writer *nw)
293 {
294 int off = nlattr_add_nested(nw, IFLA_LINKINFO);
295
296 if (off != 0) {
297 nlattr_add_string(nw, IFLA_INFO_KIND, ifp->if_dname);
298 nlattr_set_len(nw, off);
299 }
300 }
301
302 void
ifc_link_ifp(struct if_clone * ifc,struct ifnet * ifp)303 ifc_link_ifp(struct if_clone *ifc, struct ifnet *ifp)
304 {
305
306 if_addgroup(ifp, ifc->ifc_name);
307
308 IF_CLONE_LOCK(ifc);
309 IFC_IFLIST_INSERT(ifc, ifp);
310 IF_CLONE_UNLOCK(ifc);
311 }
312
313 void
if_clone_addif(struct if_clone * ifc,struct ifnet * ifp)314 if_clone_addif(struct if_clone *ifc, struct ifnet *ifp)
315 {
316 ifc_link_ifp(ifc, ifp);
317 }
318
319 bool
ifc_unlink_ifp(struct if_clone * ifc,struct ifnet * ifp)320 ifc_unlink_ifp(struct if_clone *ifc, struct ifnet *ifp)
321 {
322 struct ifnet *ifcifp;
323
324 IF_CLONE_LOCK(ifc);
325 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
326 if (ifcifp == ifp) {
327 IFC_IFLIST_REMOVE(ifc, ifp);
328 break;
329 }
330 }
331 IF_CLONE_UNLOCK(ifc);
332
333 if (ifcifp != NULL)
334 if_delgroup(ifp, ifc->ifc_name);
335
336 return (ifcifp != NULL);
337 }
338
339 static struct if_clone *
ifc_find_cloner_match(const char * name)340 ifc_find_cloner_match(const char *name)
341 {
342 struct if_clone *ifc;
343
344 IF_CLONERS_LOCK();
345 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
346 if (ifc->ifc_match(ifc, name))
347 break;
348 }
349 IF_CLONERS_UNLOCK();
350
351 return (ifc);
352 }
353
354 static struct if_clone *
ifc_find_cloner(const char * name)355 ifc_find_cloner(const char *name)
356 {
357 struct if_clone *ifc;
358
359 IF_CLONERS_LOCK();
360 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
361 if (strcmp(ifc->ifc_name, name) == 0) {
362 break;
363 }
364 }
365 IF_CLONERS_UNLOCK();
366
367 return (ifc);
368 }
369
370 static struct if_clone *
ifc_find_cloner_in_vnet(const char * name,struct vnet * vnet)371 ifc_find_cloner_in_vnet(const char *name, struct vnet *vnet)
372 {
373 CURVNET_SET_QUIET(vnet);
374 struct if_clone *ifc = ifc_find_cloner(name);
375 CURVNET_RESTORE();
376
377 return (ifc);
378 }
379
380 /*
381 * Create a clone network interface.
382 */
383 static int
if_clone_createif_nl(struct if_clone * ifc,const char * ifname,struct ifc_data_nl * ifd)384 if_clone_createif_nl(struct if_clone *ifc, const char *ifname, struct ifc_data_nl *ifd)
385 {
386 char name[IFNAMSIZ];
387 int error;
388
389 strlcpy(name, ifname, sizeof(name));
390
391 if (ifunit(name) != NULL)
392 return (EEXIST);
393
394 if (ifc->ifc_flags & IFC_F_AUTOUNIT) {
395 if ((error = ifc_handle_unit(ifc, name, sizeof(name), &ifd->unit)) != 0)
396 return (error);
397 }
398
399 if (ifd->lattrs != NULL)
400 error = (*ifc->create_nl)(ifc, name, sizeof(name), ifd);
401 else
402 error = ifc_create_ifp_nl_default(ifc, name, sizeof(name), ifd);
403 if (error != 0) {
404 if (ifc->ifc_flags & IFC_F_AUTOUNIT)
405 ifc_free_unit(ifc, ifd->unit);
406 return (error);
407 }
408
409 MPASS(ifd->ifp != NULL);
410 if_clone_addif(ifc, ifd->ifp);
411
412 if (ifd->lattrs != NULL)
413 error = (*ifc->modify_nl)(ifd->ifp, ifd);
414
415 return (error);
416 }
417
418 /*
419 * Lookup and destroy a clone network interface.
420 */
421 int
if_clone_destroy(const char * name)422 if_clone_destroy(const char *name)
423 {
424 int err;
425 struct if_clone *ifc;
426 struct ifnet *ifp;
427
428 ifp = ifunit_ref(name);
429 if (ifp == NULL)
430 return (ENXIO);
431
432 ifc = ifc_find_cloner_in_vnet(ifp->if_dname, ifp->if_home_vnet);
433 if (ifc == NULL) {
434 if_rele(ifp);
435 return (EINVAL);
436 }
437
438 err = if_clone_destroyif(ifc, ifp);
439 if_rele(ifp);
440 return err;
441 }
442
443 /*
444 * Destroy a clone network interface.
445 */
446 static int
if_clone_destroyif_flags(struct if_clone * ifc,struct ifnet * ifp,uint32_t flags)447 if_clone_destroyif_flags(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags)
448 {
449 int err;
450
451 /*
452 * Given that the cloned ifnet might be attached to a different
453 * vnet from where its cloner was registered, we have to
454 * switch to the vnet context of the target vnet.
455 */
456 CURVNET_SET_QUIET(ifp->if_vnet);
457
458 if (!ifc_unlink_ifp(ifc, ifp)) {
459 CURVNET_RESTORE();
460 return (ENXIO); /* ifp is not on the list. */
461 }
462
463 int unit = ifp->if_dunit;
464 err = (*ifc->ifc_destroy)(ifc, ifp, flags);
465
466 if (err != 0)
467 ifc_link_ifp(ifc, ifp);
468 else if (ifc->ifc_flags & IFC_F_AUTOUNIT)
469 ifc_free_unit(ifc, unit);
470 CURVNET_RESTORE();
471 return (err);
472 }
473
474 int
if_clone_destroyif(struct if_clone * ifc,struct ifnet * ifp)475 if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
476 {
477 return (if_clone_destroyif_flags(ifc, ifp, 0));
478 }
479
480 static struct if_clone *
if_clone_alloc(const char * name,int maxunit)481 if_clone_alloc(const char *name, int maxunit)
482 {
483 struct if_clone *ifc;
484
485 KASSERT(name != NULL, ("%s: no name\n", __func__));
486
487 ifc = malloc(sizeof(struct if_clone), M_CLONE, M_WAITOK | M_ZERO);
488 strncpy(ifc->ifc_name, name, IFCLOSIZ-1);
489 IF_CLONE_LOCK_INIT(ifc);
490 IF_CLONE_ADDREF(ifc);
491 ifc->ifc_maxunit = maxunit ? maxunit : IF_MAXUNIT;
492 ifc->ifc_unrhdr = new_unrhdr(0, ifc->ifc_maxunit, &ifc->ifc_mtx);
493 LIST_INIT(&ifc->ifc_iflist);
494
495 ifc->create_nl = ifc_create_ifp_nl_default;
496 ifc->modify_nl = ifc_modify_ifp_nl_default;
497 ifc->dump_nl = ifc_dump_ifp_nl_default;
498
499 return (ifc);
500 }
501
502 static int
if_clone_attach(struct if_clone * ifc)503 if_clone_attach(struct if_clone *ifc)
504 {
505 struct if_clone *ifc1;
506
507 IF_CLONERS_LOCK();
508 LIST_FOREACH(ifc1, &V_if_cloners, ifc_list)
509 if (strcmp(ifc->ifc_name, ifc1->ifc_name) == 0) {
510 IF_CLONERS_UNLOCK();
511 IF_CLONE_REMREF(ifc);
512 return (EEXIST);
513 }
514 LIST_INSERT_HEAD(&V_if_cloners, ifc, ifc_list);
515 V_if_cloners_count++;
516 IF_CLONERS_UNLOCK();
517
518 return (0);
519 }
520
521 struct if_clone *
ifc_attach_cloner(const char * name,struct if_clone_addreq * req)522 ifc_attach_cloner(const char *name, struct if_clone_addreq *req)
523 {
524 if (req->create_f == NULL || req->destroy_f == NULL)
525 return (NULL);
526 if (strnlen(name, IFCLOSIZ) >= (IFCLOSIZ - 1))
527 return (NULL);
528
529 struct if_clone *ifc = if_clone_alloc(name, req->maxunit);
530 ifc->ifc_match = req->match_f != NULL ? req->match_f : ifc_simple_match;
531 ifc->ifc_create = req->create_f;
532 ifc->ifc_destroy = req->destroy_f;
533 ifc->ifc_flags = (req->flags & IFC_F_AUTOUNIT);
534
535 if (req->version == 2) {
536 struct if_clone_addreq_v2 *req2 = (struct if_clone_addreq_v2 *)req;
537
538 ifc->create_nl = req2->create_nl_f;
539 ifc->modify_nl = req2->modify_nl_f;
540 ifc->dump_nl = req2->dump_nl_f;
541 }
542
543 ifc->dump_nl = ifc_dump_ifp_nl_default;
544
545 if (if_clone_attach(ifc) != 0)
546 return (NULL);
547
548 EVENTHANDLER_INVOKE(if_clone_event, ifc);
549
550 return (ifc);
551 }
552
553 void
ifc_detach_cloner(struct if_clone * ifc)554 ifc_detach_cloner(struct if_clone *ifc)
555 {
556 if_clone_detach(ifc);
557 }
558
559
560 #ifdef CLONE_COMPAT_13
561
562 static int
ifc_advanced_create_wrapper(struct if_clone * ifc,char * name,size_t maxlen,struct ifc_data * ifc_data,struct ifnet ** ifpp)563 ifc_advanced_create_wrapper(struct if_clone *ifc, char *name, size_t maxlen,
564 struct ifc_data *ifc_data, struct ifnet **ifpp)
565 {
566 int error = ifc->ifca_create(ifc, name, maxlen, ifc_data->params);
567
568 if (error == 0)
569 *ifpp = ifunit(name);
570 return (error);
571 }
572
573 static int
ifc_advanced_destroy_wrapper(struct if_clone * ifc,struct ifnet * ifp,uint32_t flags)574 ifc_advanced_destroy_wrapper(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags)
575 {
576 if (ifc->ifca_destroy == NULL)
577 return (ENOTSUP);
578 return (ifc->ifca_destroy(ifc, ifp));
579 }
580
581 struct if_clone *
if_clone_advanced(const char * name,u_int maxunit,ifc_match_t match,ifc_create_t create,ifc_destroy_t destroy)582 if_clone_advanced(const char *name, u_int maxunit, ifc_match_t match,
583 ifc_create_t create, ifc_destroy_t destroy)
584 {
585 struct if_clone *ifc;
586
587 ifc = if_clone_alloc(name, maxunit);
588 ifc->ifc_match = match;
589 ifc->ifc_create = ifc_advanced_create_wrapper;
590 ifc->ifc_destroy = ifc_advanced_destroy_wrapper;
591 ifc->ifca_destroy = destroy;
592 ifc->ifca_create = create;
593
594 if (if_clone_attach(ifc) != 0)
595 return (NULL);
596
597 EVENTHANDLER_INVOKE(if_clone_event, ifc);
598
599 return (ifc);
600 }
601
602 static int
ifc_simple_create_wrapper(struct if_clone * ifc,char * name,size_t maxlen,struct ifc_data * ifc_data,struct ifnet ** ifpp)603 ifc_simple_create_wrapper(struct if_clone *ifc, char *name, size_t maxlen,
604 struct ifc_data *ifc_data, struct ifnet **ifpp)
605 {
606 int unit = 0;
607
608 ifc_name2unit(name, &unit);
609 int error = ifc->ifcs_create(ifc, unit, ifc_data->params);
610 if (error == 0)
611 *ifpp = ifunit(name);
612 return (error);
613 }
614
615 static int
ifc_simple_destroy_wrapper(struct if_clone * ifc,struct ifnet * ifp,uint32_t flags)616 ifc_simple_destroy_wrapper(struct if_clone *ifc, struct ifnet *ifp, uint32_t flags)
617 {
618 if (ifp->if_dunit < ifc->ifcs_minifs && (flags & IFC_F_FORCE) == 0)
619 return (EINVAL);
620
621 ifc->ifcs_destroy(ifp);
622 return (0);
623 }
624
625 struct if_clone *
if_clone_simple(const char * name,ifcs_create_t create,ifcs_destroy_t destroy,u_int minifs)626 if_clone_simple(const char *name, ifcs_create_t create, ifcs_destroy_t destroy,
627 u_int minifs)
628 {
629 struct if_clone *ifc;
630 u_int unit;
631
632 ifc = if_clone_alloc(name, 0);
633 ifc->ifc_match = ifc_simple_match;
634 ifc->ifc_create = ifc_simple_create_wrapper;
635 ifc->ifc_destroy = ifc_simple_destroy_wrapper;
636 ifc->ifcs_create = create;
637 ifc->ifcs_destroy = destroy;
638 ifc->ifcs_minifs = minifs;
639 ifc->ifc_flags = IFC_F_AUTOUNIT;
640
641 if (if_clone_attach(ifc) != 0)
642 return (NULL);
643
644 for (unit = 0; unit < minifs; unit++) {
645 char name[IFNAMSIZ];
646 int error __unused;
647 struct ifc_data_nl ifd = {};
648
649 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
650 error = if_clone_createif_nl(ifc, name, &ifd);
651 KASSERT(error == 0,
652 ("%s: failed to create required interface %s",
653 __func__, name));
654 }
655
656 EVENTHANDLER_INVOKE(if_clone_event, ifc);
657
658 return (ifc);
659 }
660 #endif
661
662 /*
663 * Unregister a network interface cloner.
664 */
665 void
if_clone_detach(struct if_clone * ifc)666 if_clone_detach(struct if_clone *ifc)
667 {
668
669 IF_CLONERS_LOCK();
670 LIST_REMOVE(ifc, ifc_list);
671 V_if_cloners_count--;
672 IF_CLONERS_UNLOCK();
673
674 /* destroy all interfaces for this cloner */
675 while (!LIST_EMPTY(&ifc->ifc_iflist))
676 if_clone_destroyif_flags(ifc, LIST_FIRST(&ifc->ifc_iflist), IFC_F_FORCE);
677
678 IF_CLONE_REMREF(ifc);
679 }
680
681 static void
if_clone_free(struct if_clone * ifc)682 if_clone_free(struct if_clone *ifc)
683 {
684
685 KASSERT(LIST_EMPTY(&ifc->ifc_iflist),
686 ("%s: ifc_iflist not empty", __func__));
687
688 IF_CLONE_LOCK_DESTROY(ifc);
689 delete_unrhdr(ifc->ifc_unrhdr);
690 free(ifc, M_CLONE);
691 }
692
693 /*
694 * Provide list of interface cloners to userspace.
695 */
696 int
if_clone_list(struct if_clonereq * ifcr)697 if_clone_list(struct if_clonereq *ifcr)
698 {
699 char *buf, *dst, *outbuf = NULL;
700 struct if_clone *ifc;
701 int buf_count, count, err = 0;
702
703 if (ifcr->ifcr_count < 0)
704 return (EINVAL);
705
706 IF_CLONERS_LOCK();
707 /*
708 * Set our internal output buffer size. We could end up not
709 * reporting a cloner that is added between the unlock and lock
710 * below, but that's not a major problem. Not caping our
711 * allocation to the number of cloners actually in the system
712 * could be because that would let arbitrary users cause us to
713 * allocate arbitrary amounts of kernel memory.
714 */
715 buf_count = (V_if_cloners_count < ifcr->ifcr_count) ?
716 V_if_cloners_count : ifcr->ifcr_count;
717 IF_CLONERS_UNLOCK();
718
719 outbuf = malloc(IFNAMSIZ*buf_count, M_CLONE, M_WAITOK | M_ZERO);
720
721 IF_CLONERS_LOCK();
722
723 ifcr->ifcr_total = V_if_cloners_count;
724 if ((dst = ifcr->ifcr_buffer) == NULL) {
725 /* Just asking how many there are. */
726 goto done;
727 }
728 count = (V_if_cloners_count < buf_count) ?
729 V_if_cloners_count : buf_count;
730
731 for (ifc = LIST_FIRST(&V_if_cloners), buf = outbuf;
732 ifc != NULL && count != 0;
733 ifc = LIST_NEXT(ifc, ifc_list), count--, buf += IFNAMSIZ) {
734 strlcpy(buf, ifc->ifc_name, IFNAMSIZ);
735 }
736
737 done:
738 IF_CLONERS_UNLOCK();
739 if (err == 0 && dst != NULL)
740 err = copyout(outbuf, dst, buf_count*IFNAMSIZ);
741 if (outbuf != NULL)
742 free(outbuf, M_CLONE);
743 return (err);
744 }
745
746 #ifdef VIMAGE
747 /*
748 * if_clone_restoregroup() is used in context of if_vmove().
749 *
750 * Since if_detach_internal() has removed the interface from ALL groups, we
751 * need to "restore" interface membership in the cloner's group. Note that
752 * interface belongs to cloner in its home vnet, so we first find the original
753 * cloner, and then we confirm that cloner with the same name exists in the
754 * current vnet.
755 */
756 void
if_clone_restoregroup(struct ifnet * ifp)757 if_clone_restoregroup(struct ifnet *ifp)
758 {
759 struct if_clone *ifc;
760 struct ifnet *ifcifp;
761 char ifc_name[IFCLOSIZ] = { [0] = '\0' };
762
763 CURVNET_SET_QUIET(ifp->if_home_vnet);
764 IF_CLONERS_LOCK();
765 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
766 IF_CLONE_LOCK(ifc);
767 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
768 if (ifp == ifcifp) {
769 strncpy(ifc_name, ifc->ifc_name, IFCLOSIZ-1);
770 break;
771 }
772 }
773 IF_CLONE_UNLOCK(ifc);
774 if (ifc_name[0] != '\0')
775 break;
776 }
777 CURVNET_RESTORE();
778 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
779 if (strcmp(ifc->ifc_name, ifc_name) == 0)
780 break;
781 IF_CLONERS_UNLOCK();
782
783 if (ifc != NULL)
784 if_addgroup(ifp, ifc_name);
785 }
786 #endif
787
788 /*
789 * A utility function to extract unit numbers from interface names of
790 * the form name###.
791 *
792 * Returns 0 on success and an error on failure.
793 */
794 int
ifc_name2unit(const char * name,int * unit)795 ifc_name2unit(const char *name, int *unit)
796 {
797 const char *cp;
798 int cutoff = INT_MAX / 10;
799 int cutlim = INT_MAX % 10;
800
801 for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++)
802 ;
803 if (*cp == '\0') {
804 *unit = -1;
805 } else if (cp[0] == '0' && cp[1] != '\0') {
806 /* Disallow leading zeroes. */
807 return (EINVAL);
808 } else {
809 for (*unit = 0; *cp != '\0'; cp++) {
810 if (*cp < '0' || *cp > '9') {
811 /* Bogus unit number. */
812 return (EINVAL);
813 }
814 if (*unit > cutoff ||
815 (*unit == cutoff && *cp - '0' > cutlim))
816 return (EINVAL);
817 *unit = (*unit * 10) + (*cp - '0');
818 }
819 }
820
821 return (0);
822 }
823
824 static int
ifc_alloc_unit_specific(struct if_clone * ifc,int * unit)825 ifc_alloc_unit_specific(struct if_clone *ifc, int *unit)
826 {
827 char name[IFNAMSIZ];
828
829 if (*unit > ifc->ifc_maxunit)
830 return (ENOSPC);
831
832 if (alloc_unr_specific(ifc->ifc_unrhdr, *unit) == -1)
833 return (EEXIST);
834
835 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, *unit);
836 if (ifunit(name) != NULL) {
837 free_unr(ifc->ifc_unrhdr, *unit);
838 return (EEXIST);
839 }
840
841 IF_CLONE_ADDREF(ifc);
842
843 return (0);
844 }
845
846 static int
ifc_alloc_unit_next(struct if_clone * ifc,int * unit)847 ifc_alloc_unit_next(struct if_clone *ifc, int *unit)
848 {
849 int error;
850
851 *unit = alloc_unr(ifc->ifc_unrhdr);
852 if (*unit == -1)
853 return (ENOSPC);
854
855 free_unr(ifc->ifc_unrhdr, *unit);
856 for (;;) {
857 error = ifc_alloc_unit_specific(ifc, unit);
858 if (error != EEXIST)
859 break;
860
861 (*unit)++;
862 }
863
864 return (error);
865 }
866
867 int
ifc_alloc_unit(struct if_clone * ifc,int * unit)868 ifc_alloc_unit(struct if_clone *ifc, int *unit)
869 {
870 if (*unit < 0)
871 return (ifc_alloc_unit_next(ifc, unit));
872 else
873 return (ifc_alloc_unit_specific(ifc, unit));
874 }
875
876 void
ifc_free_unit(struct if_clone * ifc,int unit)877 ifc_free_unit(struct if_clone *ifc, int unit)
878 {
879
880 free_unr(ifc->ifc_unrhdr, unit);
881 IF_CLONE_REMREF(ifc);
882 }
883
884 static int
ifc_simple_match(struct if_clone * ifc,const char * name)885 ifc_simple_match(struct if_clone *ifc, const char *name)
886 {
887 const char *cp;
888 int i;
889
890 /* Match the name */
891 for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) {
892 if (ifc->ifc_name[i] != *cp)
893 return (0);
894 }
895
896 /* Make sure there's a unit number or nothing after the name */
897 for (; *cp != '\0'; cp++) {
898 if (*cp < '0' || *cp > '9')
899 return (0);
900 }
901
902 return (1);
903 }
904
905 static int
ifc_handle_unit(struct if_clone * ifc,char * name,size_t len,int * punit)906 ifc_handle_unit(struct if_clone *ifc, char *name, size_t len, int *punit)
907 {
908 char *dp;
909 int wildcard;
910 int unit;
911 int err;
912
913 err = ifc_name2unit(name, &unit);
914 if (err != 0)
915 return (err);
916
917 wildcard = (unit < 0);
918
919 err = ifc_alloc_unit(ifc, &unit);
920 if (err != 0)
921 return (err);
922
923 /* In the wildcard case, we need to update the name. */
924 if (wildcard) {
925 for (dp = name; *dp != '\0'; dp++);
926 if (snprintf(dp, len - (dp-name), "%d", unit) >
927 len - (dp-name) - 1) {
928 /*
929 * This can only be a programmer error and
930 * there's no straightforward way to recover if
931 * it happens.
932 */
933 panic("if_clone_create(): interface name too long");
934 }
935 }
936 *punit = unit;
937
938 return (0);
939 }
940
941 int
ifc_copyin(const struct ifc_data * ifd,void * target,size_t len)942 ifc_copyin(const struct ifc_data *ifd, void *target, size_t len)
943 {
944 if (ifd->params == NULL)
945 return (EINVAL);
946
947 if (ifd->flags & IFC_F_SYSSPACE) {
948 memcpy(target, ifd->params, len);
949 return (0);
950 } else
951 return (copyin(ifd->params, target, len));
952 }
953