diff options
Diffstat (limited to 'sys/net/if_clone.c')
-rw-r--r-- | sys/net/if_clone.c | 468 |
1 files changed, 468 insertions, 0 deletions
diff --git a/sys/net/if_clone.c b/sys/net/if_clone.c new file mode 100644 index 0000000..37184b2 --- /dev/null +++ b/sys/net/if_clone.c @@ -0,0 +1,468 @@ +/* + * Copyright (c) 1980, 1986, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * @(#)if.c 8.5 (Berkeley) 1/9/95 + * $FreeBSD$ + */ + +#include <sys/param.h> +#include <sys/malloc.h> +#include <sys/lock.h> +#include <sys/mutex.h> +#include <sys/kernel.h> +#include <sys/systm.h> +#include <sys/types.h> +#include <sys/socket.h> + +#include <net/if.h> +#include <net/if_clone.h> +#if 0 +#include <net/if_dl.h> +#endif +#include <net/if_types.h> +#include <net/if_var.h> +#include <net/radix.h> +#include <net/route.h> + +static void if_clone_free(struct if_clone *ifc); + +static struct mtx if_cloners_mtx; +static int if_cloners_count; +LIST_HEAD(, if_clone) if_cloners = LIST_HEAD_INITIALIZER(if_cloners); + +#define IF_CLONERS_LOCK_INIT() \ + mtx_init(&if_cloners_mtx, "if_cloners lock", NULL, MTX_DEF) +#define IF_CLONERS_LOCK_ASSERT() mtx_assert(&if_cloners_mtx, MA_OWNED) +#define IF_CLONERS_LOCK() mtx_lock(&if_cloners_mtx) +#define IF_CLONERS_UNLOCK() mtx_unlock(&if_cloners_mtx) + +#define IF_CLONE_LOCK_INIT(ifc) \ + mtx_init(&(ifc)->ifc_mtx, "if_clone lock", NULL, MTX_DEF) +#define IF_CLONE_LOCK_DESTROY(ifc) mtx_destroy(&(ifc)->ifc_mtx) +#define IF_CLONE_LOCK_ASSERT(ifc) mtx_assert(&(ifc)->ifc_mtx, MA_OWNED) +#define IF_CLONE_LOCK(ifc) mtx_lock(&(ifc)->ifc_mtx) +#define IF_CLONE_UNLOCK(ifc) mtx_unlock(&(ifc)->ifc_mtx) + +#define IF_CLONE_ADDREF(ifc) \ + do { \ + IF_CLONE_LOCK(ifc); \ + IF_CLONE_ADDREF_LOCKED(ifc); \ + IF_CLONE_UNLOCK(ifc); \ + } while (0) +#define IF_CLONE_ADDREF_LOCKED(ifc) \ + do { \ + IF_CLONE_LOCK_ASSERT(ifc); \ + KASSERT((ifc)->ifc_refcnt >= 0, \ + ("negative refcnt %ld", (ifc)->ifc_refcnt)); \ + (ifc)->ifc_refcnt++; \ + } while (0) +#define IF_CLONE_REMREF(ifc) \ + do { \ + IF_CLONE_LOCK(ifc); \ + IF_CLONE_REMREF_LOCKED(ifc); \ + } while (0) +#define IF_CLONE_REMREF_LOCKED(ifc) \ + do { \ + IF_CLONE_LOCK_ASSERT(ifc); \ + KASSERT((ifc)->ifc_refcnt > 0, \ + ("bogus refcnt %ld", (ifc)->ifc_refcnt)); \ + if (--(ifc)->ifc_refcnt == 0) { \ + IF_CLONE_UNLOCK(ifc); \ + if_clone_free(ifc); \ + } \ + /* silently free the lock */ \ + IF_CLONE_UNLOCK(ifc); \ + } while (0) + +MALLOC_DEFINE(M_CLONE, "clone", "interface cloning framework"); + +void +if_clone_init(void) +{ + IF_CLONERS_LOCK_INIT(); +} + +/* + * Create a clone network interface. + */ +int +if_clone_create(char *name, size_t len) +{ + int err; + struct if_clone *ifc; + + if (ifunit(name) != NULL) + return (EEXIST); + + /* Try to find an applicable cloner for this request */ + IF_CLONERS_LOCK(); + LIST_FOREACH(ifc, &if_cloners, ifc_list) { + if (ifc->ifc_match(ifc, name)) { + IF_CLONE_ADDREF(ifc); + break; + } + } + IF_CLONERS_UNLOCK(); + + if (ifc == NULL) + return (EINVAL); + + err = (*ifc->ifc_create)(ifc, name, len); + IF_CLONE_REMREF(ifc); + return (err); +} + +/* + * Destroy a clone network interface. + */ +int +if_clone_destroy(const char *name) +{ + int err; + struct if_clone *ifc; + struct ifnet *ifp; + + ifp = ifunit(name); + if (ifp == NULL) + return (ENXIO); + + /* Find the cloner for this interface */ + IF_CLONERS_LOCK(); + LIST_FOREACH(ifc, &if_cloners, ifc_list) { + if (strcmp(ifc->ifc_name, ifp->if_dname) == 0) { + IF_CLONE_ADDREF(ifc); + break; + } + } + IF_CLONERS_UNLOCK(); + if (ifc == NULL) + return (EINVAL); + + if (ifc->ifc_destroy == NULL) { + err = EOPNOTSUPP; + goto done; + } + + err = (*ifc->ifc_destroy)(ifc, ifp); + +done: + IF_CLONE_REMREF(ifc); + return (err); +} + +/* + * Register a network interface cloner. + */ +void +if_clone_attach(struct if_clone *ifc) +{ + int len, maxclone; + + /* + * Compute bitmap size and allocate it. + */ + maxclone = ifc->ifc_maxunit + 1; + len = maxclone >> 3; + if ((len << 3) < maxclone) + len++; + ifc->ifc_units = malloc(len, M_CLONE, M_WAITOK | M_ZERO); + ifc->ifc_bmlen = len; + IF_CLONE_LOCK_INIT(ifc); + IF_CLONE_ADDREF(ifc); + + IF_CLONERS_LOCK(); + LIST_INSERT_HEAD(&if_cloners, ifc, ifc_list); + if_cloners_count++; + IF_CLONERS_UNLOCK(); + + if (ifc->ifc_attach != NULL) + (*ifc->ifc_attach)(ifc); + EVENTHANDLER_INVOKE(if_clone_event, ifc); +} + +/* + * Unregister a network interface cloner. + */ +void +if_clone_detach(struct if_clone *ifc) +{ + + IF_CLONERS_LOCK(); + LIST_REMOVE(ifc, ifc_list); + if_cloners_count--; + IF_CLONERS_UNLOCK(); + + IF_CLONE_REMREF(ifc); +} + +static void +if_clone_free(struct if_clone *ifc) +{ + + IF_CLONE_LOCK_DESTROY(ifc); + free(ifc->ifc_units, M_CLONE); +} + +/* + * Provide list of interface cloners to userspace. + */ +int +if_clone_list(struct if_clonereq *ifcr) +{ + char outbuf[IFNAMSIZ], *dst; + struct if_clone *ifc; + int count, err = 0; + + IF_CLONERS_LOCK(); + + ifcr->ifcr_total = if_cloners_count; + if ((dst = ifcr->ifcr_buffer) == NULL) { + /* Just asking how many there are. */ + goto done; + } + + if (ifcr->ifcr_count < 0) { + err = EINVAL; + goto done; + } + + count = (if_cloners_count < ifcr->ifcr_count) ? + if_cloners_count : ifcr->ifcr_count; + + for (ifc = LIST_FIRST(&if_cloners); ifc != NULL && count != 0; + ifc = LIST_NEXT(ifc, ifc_list), count--, dst += IFNAMSIZ) { + strlcpy(outbuf, ifc->ifc_name, IFNAMSIZ); + err = copyout(outbuf, dst, IFNAMSIZ); + if (err) + break; + } + +done: + IF_CLONERS_UNLOCK(); + return (err); +} + +/* + * A utility function to extract unit numbers from interface names of + * the form name###. + * + * Returns 0 on success and an error on failure. + */ +int +ifc_name2unit(const char *name, int *unit) +{ + const char *cp; + + for (cp = name; *cp != '\0' && (*cp < '0' || *cp > '9'); cp++); + if (*cp == '\0') { + *unit = -1; + } else { + for (*unit = 0; *cp != '\0'; cp++) { + if (*cp < '0' || *cp > '9') { + /* Bogus unit number. */ + return (EINVAL); + } + *unit = (*unit * 10) + (*cp - '0'); + } + } + + return (0); +} + +int +ifc_alloc_unit(struct if_clone *ifc, int *unit) +{ + int wildcard, bytoff, bitoff; + int err = 0; + + IF_CLONE_LOCK(ifc); + + bytoff = bitoff = 0; + wildcard = (*unit < 0); + /* + * Find a free unit if none was given. + */ + if (wildcard) { + while ((bytoff < ifc->ifc_bmlen) + && (ifc->ifc_units[bytoff] == 0xff)) + bytoff++; + if (bytoff >= ifc->ifc_bmlen) { + err = ENOSPC; + goto done; + } + while ((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0) + bitoff++; + *unit = (bytoff << 3) + bitoff; + } + + if (*unit > ifc->ifc_maxunit) { + err = ENOSPC; + goto done; + } + + if (!wildcard) { + bytoff = *unit >> 3; + bitoff = *unit - (bytoff << 3); + } + + if((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0) { + err = EEXIST; + goto done; + } + /* + * Allocate the unit in the bitmap. + */ + ifc->ifc_units[bytoff] |= (1 << bitoff); + +done: + IF_CLONE_UNLOCK(ifc); + return (err); +} + +void +ifc_free_unit(struct if_clone *ifc, int unit) +{ + int bytoff, bitoff; + + + /* + * Compute offset in the bitmap and deallocate the unit. + */ + bytoff = unit >> 3; + bitoff = unit - (bytoff << 3); + + IF_CLONE_LOCK(ifc); + KASSERT((ifc->ifc_units[bytoff] & (1 << bitoff)) != 0, + ("%s: bit is already cleared", __func__)); + ifc->ifc_units[bytoff] &= ~(1 << bitoff); + IF_CLONE_UNLOCK(ifc); +} + +void +ifc_simple_attach(struct if_clone *ifc) +{ + int err; + int unit; + char name[IFNAMSIZ]; + struct ifc_simple_data *ifcs = ifc->ifc_data; + + KASSERT(ifcs->ifcs_minifs - 1 <= ifc->ifc_maxunit, + ("%s: %s requested more units then allowed (%d > %d)", + __func__, ifc->ifc_name, ifcs->ifcs_minifs, + ifc->ifc_maxunit + 1)); + + for (unit = 0; unit < ifcs->ifcs_minifs; unit++) { + snprintf(name, IFNAMSIZ, "%s%d", ifc->ifc_name, unit); + err = (*ifc->ifc_create)(ifc, name, IFNAMSIZ); + KASSERT(err == 0, + ("%s: failed to create required interface %s", + __func__, name)); + } +} + +int +ifc_simple_match(struct if_clone *ifc, const char *name) +{ + const char *cp; + int i; + + /* Match the name */ + for (cp = name, i = 0; i < strlen(ifc->ifc_name); i++, cp++) { + if (ifc->ifc_name[i] != *cp) + return (0); + } + + /* Make sure there's a unit number or nothing after the name */ + for (; *cp != '\0'; cp++) { + if (*cp < '0' || *cp > '9') + return (0); + } + + return (1); +} + +int +ifc_simple_create(struct if_clone *ifc, char *name, size_t len) +{ + char *dp; + int wildcard; + int unit; + int err; + struct ifc_simple_data *ifcs = ifc->ifc_data; + + err = ifc_name2unit(name, &unit); + if (err != 0) + return (err); + + wildcard = (unit < 0); + + err = ifc_alloc_unit(ifc, &unit); + if (err != 0) + return (err); + + err = ifcs->ifcs_create(ifc, unit); + if (err != 0) { + ifc_free_unit(ifc, unit); + return (err); + } + + /* In the wildcard case, we need to update the name. */ + if (wildcard) { + for (dp = name; *dp != '\0'; dp++); + if (snprintf(dp, len - (dp-name), "%d", unit) > + len - (dp-name) - 1) { + /* + * This can only be a programmer error and + * there's no straightforward way to recover if + * it happens. + */ + panic("if_clone_create(): interface name too long"); + } + + } + + return (0); +} + +int +ifc_simple_destroy(struct if_clone *ifc, struct ifnet *ifp) +{ + int unit; + struct ifc_simple_data *ifcs = ifc->ifc_data; + + unit = ifp->if_dunit; + + if (unit < ifcs->ifcs_minifs) + return (EINVAL); + + ifcs->ifcs_destroy(ifp); + + ifc_free_unit(ifc, unit); + + return (0); +} |