2 * SPDX-License-Identifier: BSD-3-Clause
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.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
32 * @(#)if.c 8.5 (Berkeley) 1/9/95
36 #include <sys/param.h>
37 #include <sys/eventhandler.h>
38 #include <sys/malloc.h>
39 #include <sys/limits.h>
41 #include <sys/mutex.h>
42 #include <sys/kernel.h>
43 #include <sys/systm.h>
44 #include <sys/types.h>
45 #include <sys/socket.h>
48 #include <net/if_var.h>
49 #include <net/if_clone.h>
50 #include <net/radix.h>
51 #include <net/route.h>
54 /* Current IF_MAXUNIT expands maximum to 5 characters. */
55 #define IFCLOSIZ (IFNAMSIZ - 5)
58 * Structure describing a `cloning' interface.
61 * (c) const until freeing
62 * (d) driver specific data, may need external protection.
63 * (e) locked by if_cloners_mtx
64 * (i) locked by ifc_mtx mtx
67 char ifc_name[IFCLOSIZ]; /* (c) Name of device, e.g. `gif' */
68 struct unrhdr *ifc_unrhdr; /* (c) alloc_unr(9) header */
69 int ifc_maxunit; /* (c) maximum unit number */
71 long ifc_refcnt; /* (i) Reference count. */
72 LIST_HEAD(, ifnet) ifc_iflist; /* (i) List of cloned interfaces */
73 struct mtx ifc_mtx; /* Mutex to protect members. */
75 enum { SIMPLE, ADVANCED } ifc_type; /* (c) */
77 /* (c) Driver specific cloning functions. Called with no locks held. */
79 struct { /* advanced cloner */
80 ifc_match_t *_ifc_match;
81 ifc_create_t *_ifc_create;
82 ifc_destroy_t *_ifc_destroy;
84 struct { /* simple cloner */
85 ifcs_create_t *_ifcs_create;
86 ifcs_destroy_t *_ifcs_destroy;
87 int _ifcs_minifs; /* minimum ifs */
91 #define ifc_match U.A._ifc_match
92 #define ifc_create U.A._ifc_create
93 #define ifc_destroy U.A._ifc_destroy
94 #define ifcs_create U.S._ifcs_create
95 #define ifcs_destroy U.S._ifcs_destroy
96 #define ifcs_minifs U.S._ifcs_minifs
98 LIST_ENTRY(if_clone) ifc_list; /* (e) On list of cloners */
101 static void if_clone_free(struct if_clone *ifc);
102 static int if_clone_createif(struct if_clone *ifc, char *name, size_t len,
105 static int ifc_simple_match(struct if_clone *, const char *);
106 static int ifc_simple_create(struct if_clone *, char *, size_t, caddr_t);
107 static int ifc_simple_destroy(struct if_clone *, struct ifnet *);
109 static struct mtx if_cloners_mtx;
110 MTX_SYSINIT(if_cloners_lock, &if_cloners_mtx, "if_cloners lock", MTX_DEF);
111 VNET_DEFINE_STATIC(int, if_cloners_count);
112 VNET_DEFINE(LIST_HEAD(, if_clone), if_cloners);
114 #define V_if_cloners_count VNET(if_cloners_count)
115 #define V_if_cloners VNET(if_cloners)
117 #define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED)
118 #define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx)
119 #define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx)
121 #define IF_CLONE_LOCK_INIT(ifc) \
122 mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF)
123 #define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx)
124 #define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED)
125 #define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx)
126 #define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx)
128 #define IF_CLONE_ADDREF(ifc) \
130 IF_CLONE_LOCK(ifc); \
131 IF_CLONE_ADDREF_LOCKED(ifc); \
132 IF_CLONE_UNLOCK(ifc); \
134 #define IF_CLONE_ADDREF_LOCKED(ifc) \
136 IF_CLONE_LOCK_ASSERT(ifc); \
137 KASSERT((ifc)->ifc_refcnt >= 0, \
138 ("negative refcnt %ld", (ifc)->ifc_refcnt)); \
139 (ifc)->ifc_refcnt++; \
141 #define IF_CLONE_REMREF(ifc) \
143 IF_CLONE_LOCK(ifc); \
144 IF_CLONE_REMREF_LOCKED(ifc); \
146 #define IF_CLONE_REMREF_LOCKED(ifc) \
148 IF_CLONE_LOCK_ASSERT(ifc); \
149 KASSERT((ifc)->ifc_refcnt > 0, \
150 ("bogus refcnt %ld", (ifc)->ifc_refcnt)); \
151 if (--(ifc)->ifc_refcnt == 0) { \
152 IF_CLONE_UNLOCK(ifc); \
153 if_clone_free(ifc); \
155 /* silently free the lock */ \
156 IF_CLONE_UNLOCK(ifc); \
160 #define IFC_IFLIST_INSERT(_ifc, _ifp) \
161 LIST_INSERT_HEAD(&_ifc->ifc_iflist, _ifp, if_clones)
162 #define IFC_IFLIST_REMOVE(_ifc, _ifp) \
163 LIST_REMOVE(_ifp, if_clones)
165 static MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
168 vnet_if_clone_init(void)
171 LIST_INIT(&V_if_cloners);
175 * Lookup and create a clone network interface.
178 if_clone_create(char *name, size_t len, caddr_t params)
180 struct if_clone *ifc;
182 /* Try to find an applicable cloner for this request */
184 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
185 if (ifc->ifc_type == SIMPLE) {
186 if (ifc_simple_match(ifc, name))
189 if (ifc->ifc_match(ifc, name))
197 return (if_clone_createif(ifc, name, len, params));
201 if_clone_addif(struct if_clone *ifc, struct ifnet *ifp)
204 if ((ifc->ifc_flags & IFC_NOGROUP) == 0)
205 if_addgroup(ifp, ifc->ifc_name);
208 IFC_IFLIST_INSERT(ifc, ifp);
209 IF_CLONE_UNLOCK(ifc);
213 * Create a clone network interface.
216 if_clone_createif(struct if_clone *ifc, char *name, size_t len, caddr_t params)
221 if (ifunit(name) != NULL)
224 if (ifc->ifc_type == SIMPLE)
225 err = ifc_simple_create(ifc, name, len, params);
227 err = (*ifc->ifc_create)(ifc, name, len, params);
232 panic("%s: lookup failed for %s", __func__, name);
234 if_clone_addif(ifc, ifp);
241 * Lookup and destroy a clone network interface.
244 if_clone_destroy(const char *name)
247 struct if_clone *ifc;
250 ifp = ifunit_ref(name);
254 /* Find the cloner for this interface */
255 CURVNET_SET_QUIET(ifp->if_home_vnet);
257 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
258 if (strcmp(ifc->ifc_name, ifp->if_dname) == 0) {
269 err = if_clone_destroyif(ifc, ifp);
275 * Destroy a clone network interface.
278 if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
281 struct ifnet *ifcifp;
283 if (ifc->ifc_type == ADVANCED && ifc->ifc_destroy == NULL)
287 * Given that the cloned ifnet might be attached to a different
288 * vnet from where its cloner was registered, we have to
289 * switch to the vnet context of the target vnet.
291 CURVNET_SET_QUIET(ifp->if_vnet);
294 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
296 IFC_IFLIST_REMOVE(ifc, ifp);
300 IF_CLONE_UNLOCK(ifc);
301 if (ifcifp == NULL) {
303 return (ENXIO); /* ifp is not on the list. */
305 if ((ifc->ifc_flags & IFC_NOGROUP) == 0)
306 if_delgroup(ifp, ifc->ifc_name);
308 if (ifc->ifc_type == SIMPLE)
309 err = ifc_simple_destroy(ifc, ifp);
311 err = (*ifc->ifc_destroy)(ifc, ifp);
314 if ((ifc->ifc_flags & IFC_NOGROUP) == 0)
315 if_addgroup(ifp, ifc->ifc_name);
318 IFC_IFLIST_INSERT(ifc, ifp);
319 IF_CLONE_UNLOCK(ifc);
325 static struct if_clone *
326 if_clone_alloc(const char *name, int maxunit)
328 struct if_clone *ifc;
330 KASSERT(name != NULL, ("%s: no name\n", __func__));
332 ifc = malloc(sizeof(struct if_clone), M_CLONE, M_WAITOK | M_ZERO);
333 strncpy(ifc->ifc_name, name, IFCLOSIZ-1);
334 IF_CLONE_LOCK_INIT(ifc);
335 IF_CLONE_ADDREF(ifc);
336 ifc->ifc_maxunit = maxunit ? maxunit : IF_MAXUNIT;
337 ifc->ifc_unrhdr = new_unrhdr(0, ifc->ifc_maxunit, &ifc->ifc_mtx);
338 LIST_INIT(&ifc->ifc_iflist);
344 if_clone_attach(struct if_clone *ifc)
346 struct if_clone *ifc1;
349 LIST_FOREACH(ifc1, &V_if_cloners, ifc_list)
350 if (strcmp(ifc->ifc_name, ifc1->ifc_name) == 0) {
352 IF_CLONE_REMREF(ifc);
355 LIST_INSERT_HEAD(&V_if_cloners, ifc, ifc_list);
356 V_if_cloners_count++;
363 if_clone_advanced(const char *name, u_int maxunit, ifc_match_t match,
364 ifc_create_t create, ifc_destroy_t destroy)
366 struct if_clone *ifc;
368 ifc = if_clone_alloc(name, maxunit);
369 ifc->ifc_type = ADVANCED;
370 ifc->ifc_match = match;
371 ifc->ifc_create = create;
372 ifc->ifc_destroy = destroy;
374 if (if_clone_attach(ifc) != 0)
377 EVENTHANDLER_INVOKE(if_clone_event, ifc);
383 if_clone_simple(const char *name, ifcs_create_t create, ifcs_destroy_t destroy,
386 struct if_clone *ifc;
389 ifc = if_clone_alloc(name, 0);
390 ifc->ifc_type = SIMPLE;
391 ifc->ifcs_create = create;
392 ifc->ifcs_destroy = destroy;
393 ifc->ifcs_minifs = minifs;
395 if (if_clone_attach(ifc) != 0)
398 for (unit = 0; unit < minifs; unit++) {
402 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
403 error = if_clone_createif(ifc, name, IFNAMSIZ, NULL);
405 ("%s: failed to create required interface %s",
409 EVENTHANDLER_INVOKE(if_clone_event, ifc);
415 * Unregister a network interface cloner.
418 if_clone_detach(struct if_clone *ifc)
422 LIST_REMOVE(ifc, ifc_list);
423 V_if_cloners_count--;
426 /* Allow all simples to be destroyed */
427 if (ifc->ifc_type == SIMPLE)
428 ifc->ifcs_minifs = 0;
430 /* destroy all interfaces for this cloner */
431 while (!LIST_EMPTY(&ifc->ifc_iflist))
432 if_clone_destroyif(ifc, LIST_FIRST(&ifc->ifc_iflist));
434 IF_CLONE_REMREF(ifc);
438 if_clone_free(struct if_clone *ifc)
441 KASSERT(LIST_EMPTY(&ifc->ifc_iflist),
442 ("%s: ifc_iflist not empty", __func__));
444 IF_CLONE_LOCK_DESTROY(ifc);
445 delete_unrhdr(ifc->ifc_unrhdr);
450 * Provide list of interface cloners to userspace.
453 if_clone_list(struct if_clonereq *ifcr)
455 char *buf, *dst, *outbuf = NULL;
456 struct if_clone *ifc;
457 int buf_count, count, err = 0;
459 if (ifcr->ifcr_count < 0)
464 * Set our internal output buffer size. We could end up not
465 * reporting a cloner that is added between the unlock and lock
466 * below, but that's not a major problem. Not caping our
467 * allocation to the number of cloners actually in the system
468 * could be because that would let arbitrary users cause us to
469 * allocate arbitrary amounts of kernel memory.
471 buf_count = (V_if_cloners_count < ifcr->ifcr_count) ?
472 V_if_cloners_count : ifcr->ifcr_count;
475 outbuf = malloc(IFNAMSIZ*buf_count, M_CLONE, M_WAITOK | M_ZERO);
479 ifcr->ifcr_total = V_if_cloners_count;
480 if ((dst = ifcr->ifcr_buffer) == NULL) {
481 /* Just asking how many there are. */
484 count = (V_if_cloners_count < buf_count) ?
485 V_if_cloners_count : buf_count;
487 for (ifc = LIST_FIRST(&V_if_cloners), buf = outbuf;
488 ifc != NULL && count != 0;
489 ifc = LIST_NEXT(ifc, ifc_list), count--, buf += IFNAMSIZ) {
490 strlcpy(buf, ifc->ifc_name, IFNAMSIZ);
495 if (err == 0 && dst != NULL)
496 err = copyout(outbuf, dst, buf_count*IFNAMSIZ);
498 free(outbuf, M_CLONE);
504 * if_clone_restoregroup() is used in context of if_vmove().
506 * Since if_detach_internal() has removed the interface from ALL groups, we
507 * need to "restore" interface membership in the cloner's group. Note that
508 * interface belongs to cloner in its home vnet, so we first find the original
509 * cloner, and then we confirm that cloner with the same name exists in the
513 if_clone_restoregroup(struct ifnet *ifp)
515 struct if_clone *ifc;
516 struct ifnet *ifcifp;
517 char ifc_name[IFCLOSIZ] = { [0] = '\0' };
519 CURVNET_SET_QUIET(ifp->if_home_vnet);
521 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
523 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
525 strncpy(ifc_name, ifc->ifc_name, IFCLOSIZ-1);
529 IF_CLONE_UNLOCK(ifc);
530 if (ifc_name[0] != '\0')
534 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
535 if (strcmp(ifc->ifc_name, ifc_name) == 0 &&
536 ((ifc->ifc_flags & IFC_NOGROUP) == 0))
541 if_addgroup(ifp, ifc_name);
546 * A utility function to extract unit numbers from interface names of
549 * Returns 0 on success and an error on failure.
552 ifc_name2unit(const char *name, int *unit)
555 int cutoff = INT_MAX / 10;
556 int cutlim = INT_MAX % 10;
558 for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++)
562 } else if (cp[0] == '0' && cp[1] != '\0') {
563 /* Disallow leading zeroes. */
566 for (*unit = 0; *cp != '\0'; cp++) {
567 if (*cp < '0' || *cp > '9') {
568 /* Bogus unit number. */
571 if (*unit > cutoff ||
572 (*unit == cutoff && *cp - '0' > cutlim))
574 *unit = (*unit * 10) + (*cp - '0');
582 ifc_alloc_unit_specific(struct if_clone *ifc, int *unit)
586 if (*unit > ifc->ifc_maxunit)
589 if (alloc_unr_specific(ifc->ifc_unrhdr, *unit) == -1)
592 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, *unit);
593 if (ifunit(name) != NULL) {
594 free_unr(ifc->ifc_unrhdr, *unit);
598 IF_CLONE_ADDREF(ifc);
604 ifc_alloc_unit_next(struct if_clone *ifc, int *unit)
608 *unit = alloc_unr(ifc->ifc_unrhdr);
612 free_unr(ifc->ifc_unrhdr, *unit);
614 error = ifc_alloc_unit_specific(ifc, unit);
625 ifc_alloc_unit(struct if_clone *ifc, int *unit)
628 return (ifc_alloc_unit_next(ifc, unit));
630 return (ifc_alloc_unit_specific(ifc, unit));
634 ifc_free_unit(struct if_clone *ifc, int unit)
637 free_unr(ifc->ifc_unrhdr, unit);
638 IF_CLONE_REMREF(ifc);
642 ifc_simple_match(struct if_clone *ifc, const char *name)
648 for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) {
649 if (ifc->ifc_name[i] != *cp)
653 /* Make sure there's a unit number or nothing after the name */
654 for (; *cp != '\0'; cp++) {
655 if (*cp < '0' || *cp > '9')
663 ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
670 err = ifc_name2unit(name, &unit);
674 wildcard = (unit < 0);
676 err = ifc_alloc_unit(ifc, &unit);
680 err = ifc->ifcs_create(ifc, unit, params);
682 ifc_free_unit(ifc, unit);
686 /* In the wildcard case, we need to update the name. */
688 for (dp = name; *dp != '\0'; dp++);
689 if (snprintf(dp, len - (dp-name), "%d", unit) >
690 len - (dp-name) - 1) {
692 * This can only be a programmer error and
693 * there's no straightforward way to recover if
696 panic("if_clone_create(): interface name too long");
704 ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp)
708 unit = ifp->if_dunit;
710 if (unit < ifc->ifcs_minifs)
713 ifc->ifcs_destroy(ifp);
715 ifc_free_unit(ifc, unit);
721 ifc_name(struct if_clone *ifc)
723 return (ifc->ifc_name);
727 ifc_flags_set(struct if_clone *ifc, int flags)
729 ifc->ifc_flags = flags;
733 ifc_flags_get(struct if_clone *ifc)
735 return (ifc->ifc_flags);