FreeBSD-5.3/sys/netgraph/ng_eiface.c
/*-
*
* Copyright (c) 1999-2001, Vitaly V Belekhov
* 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 unmodified, 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.
*
* $FreeBSD: src/sys/netgraph/ng_eiface.c,v 1.17 2004/07/14 20:26:29 rwatson Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/mutex.h>
#include <sys/errno.h>
#include <sys/sockio.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_eiface.h>
#include <net/bpf.h>
#include <net/ethernet.h>
#include <net/if_arp.h>
static const struct ng_cmdlist ng_eiface_cmdlist[] = {
{
NGM_EIFACE_COOKIE,
NGM_EIFACE_SET,
"set",
&ng_parse_enaddr_type,
NULL
},
{ 0 }
};
/* Node private data */
struct ng_eiface_private {
struct arpcom arpcom; /* per-interface network data */
struct ifnet *ifp; /* This interface */
int unit; /* Interface unit number */
node_p node; /* Our netgraph node */
hook_p ether; /* Hook for ethernet stream */
};
typedef struct ng_eiface_private *priv_p;
/* Interface methods */
static void ng_eiface_init(void *xsc);
static void ng_eiface_start(struct ifnet *ifp);
static int ng_eiface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
#ifdef DEBUG
static void ng_eiface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
#endif
/* Netgraph methods */
static ng_constructor_t ng_eiface_constructor;
static ng_rcvmsg_t ng_eiface_rcvmsg;
static ng_shutdown_t ng_eiface_rmnode;
static ng_newhook_t ng_eiface_newhook;
static ng_rcvdata_t ng_eiface_rcvdata;
static ng_connect_t ng_eiface_connect;
static ng_disconnect_t ng_eiface_disconnect;
/* Node type descriptor */
static struct ng_type typestruct = {
.version = NG_ABI_VERSION,
.name = NG_EIFACE_NODE_TYPE,
.constructor = ng_eiface_constructor,
.rcvmsg = ng_eiface_rcvmsg,
.shutdown = ng_eiface_rmnode,
.newhook = ng_eiface_newhook,
.connect = ng_eiface_connect,
.rcvdata = ng_eiface_rcvdata,
.disconnect = ng_eiface_disconnect,
.cmdlist = ng_eiface_cmdlist
};
NETGRAPH_INIT(eiface, &typestruct);
/* We keep a bitmap indicating which unit numbers are free.
One means the unit number is free, zero means it's taken. */
static int *ng_eiface_units = NULL;
static int ng_eiface_units_len = 0;
static int ng_units_in_use = 0;
#define UNITS_BITSPERWORD (sizeof(*ng_eiface_units) * NBBY)
static struct mtx ng_eiface_mtx;
MTX_SYSINIT(ng_eiface, &ng_eiface_mtx, "ng_eiface", MTX_DEF);
/************************************************************************
HELPER STUFF
************************************************************************/
/*
* Find the first free unit number for a new interface.
* Increase the size of the unit bitmap as necessary.
*/
static __inline int
ng_eiface_get_unit(int *unit)
{
int index, bit;
mtx_lock(&ng_eiface_mtx);
for (index = 0; index < ng_eiface_units_len
&& ng_eiface_units[index] == 0; index++);
if (index == ng_eiface_units_len) { /* extend array */
int i, *newarray, newlen;
newlen = (2 * ng_eiface_units_len) + 4;
MALLOC(newarray, int *, newlen * sizeof(*ng_eiface_units),
M_NETGRAPH, M_NOWAIT);
if (newarray == NULL) {
mtx_unlock(&ng_eiface_mtx);
return (ENOMEM);
}
bcopy(ng_eiface_units, newarray,
ng_eiface_units_len * sizeof(*ng_eiface_units));
for (i = ng_eiface_units_len; i < newlen; i++)
newarray[i] = ~0;
if (ng_eiface_units != NULL)
FREE(ng_eiface_units, M_NETGRAPH);
ng_eiface_units = newarray;
ng_eiface_units_len = newlen;
}
bit = ffs(ng_eiface_units[index]) - 1;
KASSERT(bit >= 0 && bit <= UNITS_BITSPERWORD - 1,
("%s: word=%d bit=%d", __func__, ng_eiface_units[index], bit));
ng_eiface_units[index] &= ~(1 << bit);
*unit = (index * UNITS_BITSPERWORD) + bit;
ng_units_in_use++;
mtx_unlock(&ng_eiface_mtx);
return (0);
}
/*
* Free a no longer needed unit number.
*/
static __inline void
ng_eiface_free_unit(int unit)
{
int index, bit;
index = unit / UNITS_BITSPERWORD;
bit = unit % UNITS_BITSPERWORD;
mtx_lock(&ng_eiface_mtx);
KASSERT(index < ng_eiface_units_len,
("%s: unit=%d len=%d", __func__, unit, ng_eiface_units_len));
KASSERT((ng_eiface_units[index] & (1 << bit)) == 0,
("%s: unit=%d is free", __func__, unit));
ng_eiface_units[index] |= (1 << bit);
/*
* XXX We could think about reducing the size of ng_eiface_units[]
* XXX here if the last portion is all ones
* XXX At least free it if no more units.
* Needed if we are to eventually be able to unload.
*/
ng_units_in_use--;
if (ng_units_in_use == 0) { /* XXX make SMP safe */
FREE(ng_eiface_units, M_NETGRAPH);
ng_eiface_units_len = 0;
ng_eiface_units = NULL;
}
mtx_unlock(&ng_eiface_mtx);
}
/************************************************************************
INTERFACE STUFF
************************************************************************/
/*
* Process an ioctl for the virtual interface
*/
static int
ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
{
struct ifreq *const ifr = (struct ifreq *)data;
int s, error = 0;
#ifdef DEBUG
ng_eiface_print_ioctl(ifp, command, data);
#endif
s = splimp();
switch (command)
{
/* These two are mostly handled at a higher layer */
case SIOCSIFADDR:
error = ether_ioctl(ifp, command, data);
break;
case SIOCGIFADDR:
break;
/* Set flags */
case SIOCSIFFLAGS:
/*
* If the interface is marked up and stopped, then
* start it. If it is marked down and running,
* then stop it.
*/
if (ifr->ifr_flags & IFF_UP) {
if (!(ifp->if_flags & IFF_RUNNING)) {
ifp->if_flags &= ~(IFF_OACTIVE);
ifp->if_flags |= IFF_RUNNING;
}
} else {
if (ifp->if_flags & IFF_RUNNING)
ifp->if_flags
&= ~(IFF_RUNNING | IFF_OACTIVE);
}
break;
/* Set the interface MTU */
case SIOCSIFMTU:
if (ifr->ifr_mtu > NG_EIFACE_MTU_MAX
|| ifr->ifr_mtu < NG_EIFACE_MTU_MIN)
error = EINVAL;
else
ifp->if_mtu = ifr->ifr_mtu;
break;
/* Stuff that's not supported */
case SIOCADDMULTI:
case SIOCDELMULTI:
error = 0;
break;
case SIOCSIFPHYS:
error = EOPNOTSUPP;
break;
default:
error = EINVAL;
break;
}
(void)splx(s);
return (error);
}
static void
ng_eiface_init(void *xsc)
{
priv_p sc = xsc;
struct ifnet *ifp = sc->ifp;
int s;
s = splimp();
ifp->if_flags |= IFF_RUNNING;
ifp->if_flags &= ~IFF_OACTIVE;
splx(s);
}
/*
* We simply relay the packet to the ether hook, if it is connected.
* We have been throughthe netgraph locking an are guaranteed to
* be the only code running in this node at this time.
*/
static void
ng_eiface_start2(node_p node, hook_p hook, void *arg1, int arg2)
{
struct ifnet *ifp = arg1;
const priv_p priv = (priv_p) ifp->if_softc;
int len, error = 0;
struct mbuf *m;
/* Check interface flags */
if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) != (IFF_UP | IFF_RUNNING))
return;
/* Don't do anything if output is active */
if (ifp->if_flags & IFF_OACTIVE)
return;
ifp->if_flags |= IFF_OACTIVE;
/*
* Grab a packet to transmit.
*/
IF_DEQUEUE(&ifp->if_snd, m);
/* If there's nothing to send, return. */
if (m == NULL) {
ifp->if_flags &= ~IFF_OACTIVE;
return;
}
/* Berkeley packet filter
* Pass packet to bpf if there is a listener.
* XXX is this safe? locking?
*/
BPF_MTAP(ifp, m);
/* Copy length before the mbuf gets invalidated */
len = m->m_pkthdr.len;
/*
* Send packet; if hook is not connected, mbuf will get
* freed.
*/
NG_SEND_DATA_ONLY(error, priv->ether, m);
/* Update stats */
if (error == 0) {
ifp->if_obytes += len;
ifp->if_opackets++;
}
ifp->if_flags &= ~IFF_OACTIVE;
return;
}
/*
* This routine is called to deliver a packet out the interface.
* We simply queue the netgraph version to be called when netgraph locking
* allows it to happen.
* Until we know what the rest of the networking code is doing for
* locking, we don't know how we will interact with it.
* Take comfort from the fact that the ifnet struct is part of our
* private info and can't go away while we are queued.
* [Though we don't know it is still there now....]
* it is possible we don't gain anything from this because
* we would like to get the mbuf and queue it as data
* somehow, but we can't and if we did would we solve anything?
*/
static void
ng_eiface_start(struct ifnet *ifp)
{
const priv_p priv = (priv_p) ifp->if_softc;
ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0);
}
#ifdef DEBUG
/*
* Display an ioctl to the virtual interface
*/
static void
ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data){
char *str;
switch (command & IOC_DIRMASK)
{
case IOC_VOID:
str = "IO";
break;
case IOC_OUT:
str = "IOR";
break;
case IOC_IN:
str = "IOW";
break;
case IOC_INOUT:
str = "IORW";
break;
default:
str = "IO??";
}
log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
ifp->if_xname,
str,
IOCGROUP(command),
command & 0xff,
IOCPARM_LEN(command));
}
#endif /* DEBUG */
/************************************************************************
NETGRAPH NODE STUFF
************************************************************************/
/*
* Constructor for a node
*/
static int
ng_eiface_constructor(node_p node)
{
struct ifnet *ifp;
priv_p priv;
int error = 0;
/* Allocate node and interface private structures */
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK);
if (priv == NULL) {
return (ENOMEM);
}
bzero(priv, sizeof(*priv));
ifp = &(priv->arpcom.ac_if);
/* Link them together */
ifp->if_softc = priv;
priv->ifp = ifp;
/* Get an interface unit number */
if ((error = ng_eiface_get_unit(&priv->unit)) != 0) {
FREE(priv, M_NETGRAPH);
return (error);
}
/* Link together node and private info */
NG_NODE_SET_PRIVATE(node, priv);
priv->node = node;
/* Initialize interface structure */
if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
ifp->if_init = ng_eiface_init;
ifp->if_output = ether_output;
ifp->if_start = ng_eiface_start;
ifp->if_ioctl = ng_eiface_ioctl;
ifp->if_watchdog = NULL;
ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
/*
* Give this node name * bzero(ifname, sizeof(ifname));
* sprintf(ifname, "if%s", ifp->if_xname); (void)
* ng_name_node(node, ifname);
*/
/* Attach the interface */
ether_ifattach(ifp, priv->arpcom.ac_enaddr);
/* Done */
return (0);
}
/*
* Give our ok for a hook to be added
*/
static int
ng_eiface_newhook(node_p node, hook_p hook, const char *name)
{
priv_p priv = NG_NODE_PRIVATE(node);
if (strcmp(name, NG_EIFACE_HOOK_ETHER))
return (EPFNOSUPPORT);
if (priv->ether != NULL)
return (EISCONN);
priv->ether = hook;
NG_HOOK_SET_PRIVATE(hook, &priv->ether);
return (0);
}
/*
* Receive a control message
*/
static int
ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
priv_p priv = NG_NODE_PRIVATE(node);
struct ifnet *const ifp = priv->ifp;
struct ng_mesg *resp = NULL;
int error = 0;
struct ng_mesg *msg;
NGI_GET_MSG(item, msg);
switch (msg->header.typecookie) {
case NGM_EIFACE_COOKIE:
switch (msg->header.cmd) {
case NGM_EIFACE_SET:
{
struct ether_addr *eaddr;
struct ifaddr *ifa;
struct sockaddr_dl *sdl;
if (msg->header.arglen != sizeof(struct ether_addr)){
error = EINVAL;
break;
}
eaddr = (struct ether_addr *)(msg->data);
bcopy(eaddr, priv->arpcom.ac_enaddr, ETHER_ADDR_LEN);
/* And put it in the ifaddr list */
TAILQ_FOREACH(ifa, &(ifp->if_addrhead), ifa_link) {
sdl = (struct sockaddr_dl *)ifa->ifa_addr;
if (sdl->sdl_type == IFT_ETHER) {
bcopy((IFP2AC(ifp))->ac_enaddr,
LLADDR(sdl), ifp->if_addrlen);
break;
}
}
break;
}
case NGM_EIFACE_GET_IFNAME:
{
struct ng_eiface_ifname *arg;
NG_MKRESPONSE(resp, msg, sizeof(*arg), M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
arg = (struct ng_eiface_ifname *)resp->data;
strlcpy(arg->ngif_name, ifp->if_xname,
sizeof(arg->ngif_name));
break;
}
case NGM_EIFACE_GET_IFADDRS:
{
struct ifaddr *ifa;
caddr_t ptr;
int buflen;
#define SA_SIZE(s) ((s)->sa_len<sizeof(*(s))? sizeof(*(s)):(s)->sa_len)
/* Determine size of response and allocate it */
buflen = 0;
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
buflen += SA_SIZE(ifa->ifa_addr);
NG_MKRESPONSE(resp, msg, buflen, M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
/* Add addresses */
ptr = resp->data;
TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
const int len = SA_SIZE(ifa->ifa_addr);
if (buflen < len) {
log(LOG_ERR, "%s: len changed?\n",
ifp->if_xname);
break;
}
bcopy(ifa->ifa_addr, ptr, len);
ptr += len;
buflen -= len;
}
break;
#undef SA_SIZE
}
default:
error = EINVAL;
break;
} /* end of inner switch() */
break;
default:
error = EINVAL;
break;
}
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Recive data from a hook. Pass the packet to the ether_input routine.
*/
static int
ng_eiface_rcvdata(hook_p hook, item_p item)
{
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct ifnet *const ifp = priv->ifp;
struct mbuf *m;
NGI_GET_M(item, m);
/* Meta-data ends its life here... */
NG_FREE_ITEM(item);
if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING)) {
NG_FREE_M(m);
return (ENETDOWN);
}
/* Note receiving interface */
m->m_pkthdr.rcvif = ifp;
/* Update interface stats */
ifp->if_ipackets++;
(*ifp->if_input)(ifp, m);
/* Done */
return (0);
}
/*
* the node.
*/
static int
ng_eiface_rmnode(node_p node)
{
priv_p priv = NG_NODE_PRIVATE(node);
struct ifnet *const ifp = priv->ifp;
ether_ifdetach(ifp);
ng_eiface_free_unit(priv->unit);
FREE(priv, M_NETGRAPH);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(node);
return (0);
}
/*
* This is called once we've already connected a new hook to the other node.
* It gives us a chance to balk at the last minute.
*/
static int
ng_eiface_connect(hook_p hook)
{
/* be really amiable and just say "YUP that's OK by me! " */
return (0);
}
/*
* Hook disconnection
*/
static int
ng_eiface_disconnect(hook_p hook)
{
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
priv->ether = NULL;
return (0);
}