FreeBSD-5.3/sys/netgraph/ng_vlan.c
/*-
* Copyright (c) 2003 IPNET Internet Communication Company
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* Author: Ruslan Ermilov <ru@FreeBSD.org>
*
* $FreeBSD: src/sys/netgraph/ng_vlan.c,v 1.2 2004/05/29 00:51:11 julian Exp $
*/
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/systm.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_vlan_var.h>
#include <netgraph/ng_message.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_vlan.h>
#include <netgraph/netgraph.h>
static ng_constructor_t ng_vlan_constructor;
static ng_rcvmsg_t ng_vlan_rcvmsg;
static ng_shutdown_t ng_vlan_shutdown;
static ng_newhook_t ng_vlan_newhook;
static ng_rcvdata_t ng_vlan_rcvdata;
static ng_disconnect_t ng_vlan_disconnect;
/* Parse type for struct ng_vlan_filter. */
static const struct ng_parse_struct_field ng_vlan_filter_fields[] =
NG_VLAN_FILTER_FIELDS;
static const struct ng_parse_type ng_vlan_filter_type = {
&ng_parse_struct_type,
&ng_vlan_filter_fields
};
static int
ng_vlan_getTableLength(const struct ng_parse_type *type,
const u_char *start, const u_char *buf)
{
const struct ng_vlan_table *const table =
(const struct ng_vlan_table *)(buf - sizeof(u_int32_t));
return table->n;
}
/* Parse type for struct ng_vlan_table. */
static const struct ng_parse_array_info ng_vlan_table_array_info = {
&ng_vlan_filter_type,
ng_vlan_getTableLength
};
static const struct ng_parse_type ng_vlan_table_array_type = {
&ng_parse_array_type,
&ng_vlan_table_array_info
};
static const struct ng_parse_struct_field ng_vlan_table_fields[] =
NG_VLAN_TABLE_FIELDS;
static const struct ng_parse_type ng_vlan_table_type = {
&ng_parse_struct_type,
&ng_vlan_table_fields
};
/* List of commands and how to convert arguments to/from ASCII. */
static const struct ng_cmdlist ng_vlan_cmdlist[] = {
{
NGM_VLAN_COOKIE,
NGM_VLAN_ADD_FILTER,
"addfilter",
&ng_vlan_filter_type,
NULL
},
{
NGM_VLAN_COOKIE,
NGM_VLAN_DEL_FILTER,
"delfilter",
&ng_parse_hookbuf_type,
NULL
},
{
NGM_VLAN_COOKIE,
NGM_VLAN_GET_TABLE,
"gettable",
NULL,
&ng_vlan_table_type
},
{ 0 }
};
static struct ng_type ng_vlan_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_VLAN_NODE_TYPE,
.constructor = ng_vlan_constructor,
.rcvmsg = ng_vlan_rcvmsg,
.shutdown = ng_vlan_shutdown,
.newhook = ng_vlan_newhook,
.rcvdata = ng_vlan_rcvdata,
.disconnect = ng_vlan_disconnect,
.cmdlist = ng_vlan_cmdlist,
};
NETGRAPH_INIT(vlan, &ng_vlan_typestruct);
struct filter {
LIST_ENTRY(filter) next;
u_int16_t vlan;
hook_p hook;
};
#define HASHSIZE 16
#define HASH(id) ((((id) >> 8) ^ ((id) >> 4) ^ (id)) & 0x0f)
LIST_HEAD(filterhead, filter);
typedef struct {
hook_p downstream_hook;
hook_p nomatch_hook;
struct filterhead hashtable[HASHSIZE];
u_int32_t nent;
} *priv_p;
static struct filter *
ng_vlan_findentry(priv_p priv, u_int16_t vlan)
{
struct filterhead *chain = &priv->hashtable[HASH(vlan)];
struct filter *f;
LIST_FOREACH(f, chain, next)
if (f->vlan == vlan)
return (f);
return (NULL);
}
static int
ng_vlan_constructor(node_p node)
{
priv_p priv;
int i;
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL)
return (ENOMEM);
for (i = 0; i < HASHSIZE; i++)
LIST_INIT(&priv->hashtable[i]);
NG_NODE_SET_PRIVATE(node, priv);
return (0);
}
static int
ng_vlan_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p priv = NG_NODE_PRIVATE(node);
if (strcmp(name, NG_VLAN_HOOK_DOWNSTREAM) == 0)
priv->downstream_hook = hook;
else if (strcmp(name, NG_VLAN_HOOK_NOMATCH) == 0)
priv->nomatch_hook = hook;
else {
/*
* Any other hook name is valid and can
* later be associated with a filter rule.
*/
}
NG_HOOK_SET_PRIVATE(hook, NULL);
return (0);
}
static int
ng_vlan_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = NG_NODE_PRIVATE(node);
int error = 0;
struct ng_mesg *msg, *resp = NULL;
struct ng_vlan_filter *vf;
struct filter *f;
hook_p hook;
struct ng_vlan_table *t;
int i;
NGI_GET_MSG(item, msg);
/* Deal with message according to cookie and command. */
switch (msg->header.typecookie) {
case NGM_VLAN_COOKIE:
switch (msg->header.cmd) {
case NGM_VLAN_ADD_FILTER:
/* Check that message is long enough. */
if (msg->header.arglen != sizeof(*vf)) {
error = EINVAL;
break;
}
vf = (struct ng_vlan_filter *)msg->data;
/* Sanity check the VLAN ID value. */
if (vf->vlan & ~EVL_VLID_MASK) {
error = EINVAL;
break;
}
/* Check that a referenced hook exists. */
hook = ng_findhook(node, vf->hook);
if (hook == NULL) {
error = ENOENT;
break;
}
/* And is not one of the special hooks. */
if (hook == priv->downstream_hook ||
hook == priv->nomatch_hook) {
error = EINVAL;
break;
}
/* And is not already in service. */
if (NG_HOOK_PRIVATE(hook) != NULL) {
error = EEXIST;
break;
}
/* Check we don't already trap this VLAN. */
if (ng_vlan_findentry(priv, vf->vlan)) {
error = EEXIST;
break;
}
/* Create filter. */
MALLOC(f, struct filter *, sizeof(*f),
M_NETGRAPH, M_NOWAIT | M_ZERO);
if (f == NULL) {
error = ENOMEM;
break;
}
/* Link filter and hook together. */
f->hook = hook;
f->vlan = vf->vlan;
NG_HOOK_SET_PRIVATE(hook, f);
/* Register filter in a hash table. */
LIST_INSERT_HEAD(
&priv->hashtable[HASH(f->vlan)], f, next);
priv->nent++;
break;
case NGM_VLAN_DEL_FILTER:
/* Check that message is long enough. */
if (msg->header.arglen != NG_HOOKSIZ) {
error = EINVAL;
break;
}
/* Check that hook exists and is active. */
hook = ng_findhook(node, (char *)msg->data);
if (hook == NULL ||
(f = NG_HOOK_PRIVATE(hook)) == NULL) {
error = ENOENT;
break;
}
/* Purge a rule that refers to this hook. */
NG_HOOK_SET_PRIVATE(hook, NULL);
LIST_REMOVE(f, next);
priv->nent--;
FREE(f, M_NETGRAPH);
break;
case NGM_VLAN_GET_TABLE:
NG_MKRESPONSE(resp, msg, sizeof(*t) +
priv->nent * sizeof(*t->filter), M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
t = (struct ng_vlan_table *)resp->data;
t->n = priv->nent;
vf = &t->filter[0];
for (i = 0; i < HASHSIZE; i++) {
LIST_FOREACH(f, &priv->hashtable[i], next) {
vf->vlan = f->vlan;
strncpy(vf->hook, NG_HOOK_NAME(f->hook),
NG_HOOKSIZ);
vf++;
}
}
break;
default: /* Unknown command. */
error = EINVAL;
break;
}
break;
default: /* Unknown type cookie. */
error = EINVAL;
break;
}
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
static int
ng_vlan_rcvdata(hook_p hook, item_p item)
{
const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct ether_header *eh;
struct ether_vlan_header *evl;
int error;
u_int16_t vlan;
struct mbuf *m;
struct m_tag *mtag;
struct filter *f;
/* Make sure we have an entire header. */
NGI_GET_M(item, m);
if (m->m_len < sizeof(*eh) &&
(m = m_pullup(m, sizeof(*eh))) == NULL) {
NG_FREE_ITEM(item);
return (EINVAL);
}
eh = mtod(m, struct ether_header *);
if (hook == priv->downstream_hook) {
/*
* If from downstream, select between a match hook
* or the nomatch hook.
*/
mtag = m_tag_locate(m, MTAG_VLAN, MTAG_VLAN_TAG, NULL);
if (mtag != NULL || eh->ether_type == htons(ETHERTYPE_VLAN)) {
if (mtag != NULL) {
/*
* Packet is tagged, m contains a normal
* Ethernet frame; tag is stored out-of-band.
*/
vlan = EVL_VLANOFTAG(VLAN_TAG_VALUE(mtag));
(void)&evl; /* XXX silence GCC */
} else {
if (m->m_len < sizeof(*evl) &&
(m = m_pullup(m, sizeof(*evl))) == NULL) {
NG_FREE_ITEM(item);
return (EINVAL);
}
evl = mtod(m, struct ether_vlan_header *);
vlan = EVL_VLANOFTAG(ntohs(evl->evl_tag));
}
if ((f = ng_vlan_findentry(priv, vlan)) != NULL) {
if (mtag != NULL)
m_tag_delete(m, mtag);
else {
evl->evl_encap_proto = evl->evl_proto;
bcopy(mtod(m, caddr_t),
mtod(m, caddr_t) +
ETHER_VLAN_ENCAP_LEN,
ETHER_HDR_LEN);
m_adj(m, ETHER_VLAN_ENCAP_LEN);
}
}
} else
f = NULL;
if (f != NULL)
NG_FWD_NEW_DATA(error, item, f->hook, m);
else
NG_FWD_NEW_DATA(error, item, priv->nomatch_hook, m);
} else {
/*
* It is heading towards the downstream.
* If from nomatch, pass it unmodified.
* Otherwise, do the VLAN encapsulation.
*/
if (hook != priv->nomatch_hook) {
if ((f = NG_HOOK_PRIVATE(hook)) == NULL) {
NG_FREE_ITEM(item);
NG_FREE_M(m);
return (EOPNOTSUPP);
}
M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT);
/* M_PREPEND takes care of m_len and m_pkthdr.len. */
if (m == NULL || (m->m_len < sizeof(*evl) &&
(m = m_pullup(m, sizeof(*evl))) == NULL)) {
NG_FREE_ITEM(item);
return (ENOMEM);
}
/*
* Transform the Ethernet header into an Ethernet header
* with 802.1Q encapsulation.
*/
bcopy(mtod(m, char *) + ETHER_VLAN_ENCAP_LEN,
mtod(m, char *), ETHER_HDR_LEN);
evl = mtod(m, struct ether_vlan_header *);
evl->evl_proto = evl->evl_encap_proto;
evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
evl->evl_tag = htons(f->vlan);
}
NG_FWD_NEW_DATA(error, item, priv->downstream_hook, m);
}
return (error);
}
static int
ng_vlan_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node);
FREE(priv, M_NETGRAPH);
return (0);
}
static int
ng_vlan_disconnect(hook_p hook)
{
const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct filter *f;
if (hook == priv->downstream_hook)
priv->downstream_hook = NULL;
else if (hook == priv->nomatch_hook)
priv->nomatch_hook = NULL;
else {
/* Purge a rule that refers to this hook. */
if ((f = NG_HOOK_PRIVATE(hook)) != NULL) {
LIST_REMOVE(f, next);
priv->nent--;
FREE(f, M_NETGRAPH);
}
}
NG_HOOK_SET_PRIVATE(hook, NULL);
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) &&
(NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
ng_rmnode_self(NG_HOOK_NODE(hook));
return (0);
}