2 * Copyright (c) 2012 Gleb Smirnoff <glebius@FreeBSD.org>
3 * Copyright (c) 1980, 1986, 1993
4 * The Regents of the University of California. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 4. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * @(#)if.c 8.5 (Berkeley) 1/9/95
34 #include <sys/param.h>
35 #include <sys/eventhandler.h>
36 #include <sys/malloc.h>
37 #include <sys/limits.h>
39 #include <sys/mutex.h>
40 #include <sys/kernel.h>
41 #include <sys/systm.h>
42 #include <sys/types.h>
43 #include <sys/socket.h>
46 #include <net/if_var.h>
47 #include <net/if_clone.h>
48 #include <net/radix.h>
49 #include <net/route.h>
52 /* Current IF_MAXUNIT expands maximum to 5 characters. */
53 #define IFCLOSIZ (IFNAMSIZ - 5)
56 * Structure describing a `cloning' interface.
59 * (c) const until freeing
60 * (d) driver specific data, may need external protection.
61 * (e) locked by if_cloners_mtx
62 * (i) locked by ifc_mtx mtx
65 char ifc_name[IFCLOSIZ]; /* (c) Name of device, e.g. `gif' */
66 struct unrhdr *ifc_unrhdr; /* (c) alloc_unr(9) header */
67 int ifc_maxunit; /* (c) maximum unit number */
68 long ifc_refcnt; /* (i) Reference count. */
69 LIST_HEAD(, ifnet) ifc_iflist; /* (i) List of cloned interfaces */
70 struct mtx ifc_mtx; /* Mutex to protect members. */
72 enum { SIMPLE, ADVANCED } ifc_type; /* (c) */
74 /* (c) Driver specific cloning functions. Called with no locks held. */
76 struct { /* advanced cloner */
77 ifc_match_t *_ifc_match;
78 ifc_create_t *_ifc_create;
79 ifc_destroy_t *_ifc_destroy;
81 struct { /* simple cloner */
82 ifcs_create_t *_ifcs_create;
83 ifcs_destroy_t *_ifcs_destroy;
84 int _ifcs_minifs; /* minimum ifs */
88 #define ifc_match U.A._ifc_match
89 #define ifc_create U.A._ifc_create
90 #define ifc_destroy U.A._ifc_destroy
91 #define ifcs_create U.S._ifcs_create
92 #define ifcs_destroy U.S._ifcs_destroy
93 #define ifcs_minifs U.S._ifcs_minifs
95 LIST_ENTRY(if_clone) ifc_list; /* (e) On list of cloners */
98 static void if_clone_free(struct if_clone *ifc);
99 static int if_clone_createif(struct if_clone *ifc, char *name, size_t len,
102 static int ifc_simple_match(struct if_clone *, const char *);
103 static int ifc_simple_create(struct if_clone *, char *, size_t, caddr_t);
104 static int ifc_simple_destroy(struct if_clone *, struct ifnet *);
106 static struct mtx if_cloners_mtx;
107 MTX_SYSINIT(if_cloners_lock, &if_cloners_mtx, "if_cloners lock", MTX_DEF);
108 static VNET_DEFINE(int, if_cloners_count);
109 VNET_DEFINE(LIST_HEAD(, if_clone), if_cloners);
111 #define V_if_cloners_count VNET(if_cloners_count)
112 #define V_if_cloners VNET(if_cloners)
114 #define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED)
115 #define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx)
116 #define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx)
118 #define IF_CLONE_LOCK_INIT(ifc) \
119 mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF)
120 #define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx)
121 #define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED)
122 #define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx)
123 #define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx)
125 #define IF_CLONE_ADDREF(ifc) \
127 IF_CLONE_LOCK(ifc); \
128 IF_CLONE_ADDREF_LOCKED(ifc); \
129 IF_CLONE_UNLOCK(ifc); \
131 #define IF_CLONE_ADDREF_LOCKED(ifc) \
133 IF_CLONE_LOCK_ASSERT(ifc); \
134 KASSERT((ifc)->ifc_refcnt >= 0, \
135 ("negative refcnt %ld", (ifc)->ifc_refcnt)); \
136 (ifc)->ifc_refcnt++; \
138 #define IF_CLONE_REMREF(ifc) \
140 IF_CLONE_LOCK(ifc); \
141 IF_CLONE_REMREF_LOCKED(ifc); \
143 #define IF_CLONE_REMREF_LOCKED(ifc) \
145 IF_CLONE_LOCK_ASSERT(ifc); \
146 KASSERT((ifc)->ifc_refcnt > 0, \
147 ("bogus refcnt %ld", (ifc)->ifc_refcnt)); \
148 if (--(ifc)->ifc_refcnt == 0) { \
149 IF_CLONE_UNLOCK(ifc); \
150 if_clone_free(ifc); \
152 /* silently free the lock */ \
153 IF_CLONE_UNLOCK(ifc); \
157 #define IFC_IFLIST_INSERT(_ifc, _ifp) \
158 LIST_INSERT_HEAD(&_ifc->ifc_iflist, _ifp, if_clones)
159 #define IFC_IFLIST_REMOVE(_ifc, _ifp) \
160 LIST_REMOVE(_ifp, if_clones)
162 static MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework");
165 vnet_if_clone_init(void)
168 LIST_INIT(&V_if_cloners);
172 * Lookup and create a clone network interface.
175 if_clone_create(char *name, size_t len, caddr_t params)
177 struct if_clone *ifc;
179 /* Try to find an applicable cloner for this request */
181 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
182 if (ifc->ifc_type == SIMPLE) {
183 if (ifc_simple_match(ifc, name))
186 if (ifc->ifc_match(ifc, name))
190 if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
191 CURVNET_SET_QUIET(vnet0);
192 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
193 if (ifc->ifc_type == SIMPLE) {
194 if (ifc_simple_match(ifc, name))
197 if (ifc->ifc_match(ifc, name))
208 return (if_clone_createif(ifc, name, len, params));
212 * Create a clone network interface.
215 if_clone_createif(struct if_clone *ifc, char *name, size_t len, caddr_t params)
220 if (ifunit(name) != NULL)
223 if (ifc->ifc_type == SIMPLE)
224 err = ifc_simple_create(ifc, name, len, params);
226 err = (*ifc->ifc_create)(ifc, name, len, params);
231 panic("%s: lookup failed for %s", __func__, name);
233 if_addgroup(ifp, ifc->ifc_name);
236 IFC_IFLIST_INSERT(ifc, ifp);
237 IF_CLONE_UNLOCK(ifc);
244 * Lookup and destroy a clone network interface.
247 if_clone_destroy(const char *name)
250 struct if_clone *ifc;
253 ifp = ifunit_ref(name);
257 /* Find the cloner for this interface */
259 LIST_FOREACH(ifc, &V_if_cloners, ifc_list) {
260 if (strcmp(ifc->ifc_name, ifp->if_dname) == 0) {
265 if (ifc == NULL && !IS_DEFAULT_VNET(curvnet)) {
266 CURVNET_SET_QUIET(vnet0);
267 LIST_FOREACH(ifc, &V_if_cloners, ifc_list)
268 if (ifc->ifc_type == SIMPLE) {
269 if (ifc_simple_match(ifc, name))
272 if (ifc->ifc_match(ifc, name))
284 err = if_clone_destroyif(ifc, ifp);
290 * Destroy a clone network interface.
293 if_clone_destroyif(struct if_clone *ifc, struct ifnet *ifp)
296 struct ifnet *ifcifp;
298 if (ifc->ifc_type == ADVANCED && ifc->ifc_destroy == NULL)
302 * Given that the cloned ifnet might be attached to a different
303 * vnet from where its cloner was registered, we have to
304 * switch to the vnet context of the target vnet.
306 CURVNET_SET_QUIET(ifp->if_vnet);
309 LIST_FOREACH(ifcifp, &ifc->ifc_iflist, if_clones) {
311 IFC_IFLIST_REMOVE(ifc, ifp);
315 IF_CLONE_UNLOCK(ifc);
316 if (ifcifp == NULL) {
318 return (ENXIO); /* ifp is not on the list. */
321 if_delgroup(ifp, ifc->ifc_name);
323 if (ifc->ifc_type == SIMPLE)
324 err = ifc_simple_destroy(ifc, ifp);
326 err = (*ifc->ifc_destroy)(ifc, ifp);
329 if_addgroup(ifp, ifc->ifc_name);
332 IFC_IFLIST_INSERT(ifc, ifp);
333 IF_CLONE_UNLOCK(ifc);
339 static struct if_clone *
340 if_clone_alloc(const char *name, int maxunit)
342 struct if_clone *ifc;
344 KASSERT(name != NULL, ("%s: no name\n", __func__));
346 ifc = malloc(sizeof(struct if_clone), M_CLONE, M_WAITOK | M_ZERO);
347 strncpy(ifc->ifc_name, name, IFCLOSIZ-1);
348 IF_CLONE_LOCK_INIT(ifc);
349 IF_CLONE_ADDREF(ifc);
350 ifc->ifc_maxunit = maxunit ? maxunit : IF_MAXUNIT;
351 ifc->ifc_unrhdr = new_unrhdr(0, ifc->ifc_maxunit, &ifc->ifc_mtx);
352 LIST_INIT(&ifc->ifc_iflist);
358 if_clone_attach(struct if_clone *ifc)
360 struct if_clone *ifc1;
363 LIST_FOREACH(ifc1, &V_if_cloners, ifc_list)
364 if (strcmp(ifc->ifc_name, ifc1->ifc_name) == 0) {
366 IF_CLONE_REMREF(ifc);
369 LIST_INSERT_HEAD(&V_if_cloners, ifc, ifc_list);
370 V_if_cloners_count++;
377 if_clone_advanced(const char *name, u_int maxunit, ifc_match_t match,
378 ifc_create_t create, ifc_destroy_t destroy)
380 struct if_clone *ifc;
382 ifc = if_clone_alloc(name, maxunit);
383 ifc->ifc_type = ADVANCED;
384 ifc->ifc_match = match;
385 ifc->ifc_create = create;
386 ifc->ifc_destroy = destroy;
388 if (if_clone_attach(ifc) != 0) {
393 EVENTHANDLER_INVOKE(if_clone_event, ifc);
399 if_clone_simple(const char *name, ifcs_create_t create, ifcs_destroy_t destroy,
402 struct if_clone *ifc;
405 ifc = if_clone_alloc(name, 0);
406 ifc->ifc_type = SIMPLE;
407 ifc->ifcs_create = create;
408 ifc->ifcs_destroy = destroy;
409 ifc->ifcs_minifs = minifs;
411 if (if_clone_attach(ifc) != 0) {
416 for (unit = 0; unit < minifs; unit++) {
420 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit);
421 error = if_clone_createif(ifc, name, IFNAMSIZ, NULL);
423 ("%s: failed to create required interface %s",
427 EVENTHANDLER_INVOKE(if_clone_event, ifc);
433 * Unregister a network interface cloner.
436 if_clone_detach(struct if_clone *ifc)
440 LIST_REMOVE(ifc, ifc_list);
441 V_if_cloners_count--;
444 /* Allow all simples to be destroyed */
445 if (ifc->ifc_type == SIMPLE)
446 ifc->ifcs_minifs = 0;
448 /* destroy all interfaces for this cloner */
449 while (!LIST_EMPTY(&ifc->ifc_iflist))
450 if_clone_destroyif(ifc, LIST_FIRST(&ifc->ifc_iflist));
452 IF_CLONE_REMREF(ifc);
456 if_clone_free(struct if_clone *ifc)
459 KASSERT(LIST_EMPTY(&ifc->ifc_iflist),
460 ("%s: ifc_iflist not empty", __func__));
462 IF_CLONE_LOCK_DESTROY(ifc);
463 delete_unrhdr(ifc->ifc_unrhdr);
468 * Provide list of interface cloners to userspace.
471 if_clone_list(struct if_clonereq *ifcr)
473 char *buf, *dst, *outbuf = NULL;
474 struct if_clone *ifc;
475 int buf_count, count, err = 0;
477 if (ifcr->ifcr_count < 0)
482 * Set our internal output buffer size. We could end up not
483 * reporting a cloner that is added between the unlock and lock
484 * below, but that's not a major problem. Not caping our
485 * allocation to the number of cloners actually in the system
486 * could be because that would let arbitrary users cause us to
487 * allocate abritrary amounts of kernel memory.
489 buf_count = (V_if_cloners_count < ifcr->ifcr_count) ?
490 V_if_cloners_count : ifcr->ifcr_count;
493 outbuf = malloc(IFNAMSIZ*buf_count, M_CLONE, M_WAITOK | M_ZERO);
497 ifcr->ifcr_total = V_if_cloners_count;
498 if ((dst = ifcr->ifcr_buffer) == NULL) {
499 /* Just asking how many there are. */
502 count = (V_if_cloners_count < buf_count) ?
503 V_if_cloners_count : buf_count;
505 for (ifc = LIST_FIRST(&V_if_cloners), buf = outbuf;
506 ifc != NULL && count != 0;
507 ifc = LIST_NEXT(ifc, ifc_list), count--, buf += IFNAMSIZ) {
508 strlcpy(buf, ifc->ifc_name, IFNAMSIZ);
514 err = copyout(outbuf, dst, buf_count*IFNAMSIZ);
516 free(outbuf, M_CLONE);
521 * A utility function to extract unit numbers from interface names of
524 * Returns 0 on success and an error on failure.
527 ifc_name2unit(const char *name, int *unit)
530 int cutoff = INT_MAX / 10;
531 int cutlim = INT_MAX % 10;
533 for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++);
536 } else if (cp[0] == '0' && cp[1] != '\0') {
537 /* Disallow leading zeroes. */
540 for (*unit = 0; *cp != '\0'; cp++) {
541 if (*cp < '0' || *cp > '9') {
542 /* Bogus unit number. */
545 if (*unit > cutoff ||
546 (*unit == cutoff && *cp - '0' > cutlim))
548 *unit = (*unit * 10) + (*cp - '0');
556 ifc_alloc_unit(struct if_clone *ifc, int *unit)
561 wildcard = (*unit < 0);
563 if (*unit > ifc->ifc_maxunit)
566 *unit = alloc_unr(ifc->ifc_unrhdr);
570 *unit = alloc_unr_specific(ifc->ifc_unrhdr, *unit);
580 snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, *unit);
581 if (ifunit(name) != NULL) {
582 free_unr(ifc->ifc_unrhdr, *unit);
590 IF_CLONE_ADDREF(ifc);
596 ifc_free_unit(struct if_clone *ifc, int unit)
599 free_unr(ifc->ifc_unrhdr, unit);
600 IF_CLONE_REMREF(ifc);
604 ifc_simple_match(struct if_clone *ifc, const char *name)
610 for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) {
611 if (ifc->ifc_name[i] != *cp)
615 /* Make sure there's a unit number or nothing after the name */
616 for (; *cp != '\0'; cp++) {
617 if (*cp < '0' || *cp > '9')
625 ifc_simple_create(struct if_clone *ifc, char *name, size_t len, caddr_t params)
632 err = ifc_name2unit(name, &unit);
636 wildcard = (unit < 0);
638 err = ifc_alloc_unit(ifc, &unit);
642 err = ifc->ifcs_create(ifc, unit, params);
644 ifc_free_unit(ifc, unit);
648 /* In the wildcard case, we need to update the name. */
650 for (dp = name; *dp != '\0'; dp++);
651 if (snprintf(dp, len - (dp-name), "%d", unit) >
652 len - (dp-name) - 1) {
654 * This can only be a programmer error and
655 * there's no straightforward way to recover if
658 panic("if_clone_create(): interface name too long");
667 ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp)
671 unit = ifp->if_dunit;
673 if (unit < ifc->ifcs_minifs)
676 ifc->ifcs_destroy(ifp);
678 ifc_free_unit(ifc, unit);