/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2002 Mark Santcroos <marks@ripe.net>
* Copyright (c) 2004-2005 Gleb Smirnoff <glebius@FreeBSD.org>
*
* 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 ``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 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.
*
* Netgraph "device" node
*
* This node presents a /dev/ngd%d device that interfaces to an other
* netgraph node.
*
*/
#if 0
#define DBG do { printf("ng_device: %s\n", __func__ ); } while (0)
#else
#define DBG do {} while (0)
#endif
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/ioccom.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/poll.h>
#include <sys/proc.h>
#include <sys/epoch.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/systm.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_var.h>
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_device.h>
#include <netgraph/ng_parse.h>
#define ERROUT(x) do { error = (x); goto done; } while (0)
/* Netgraph methods */
static int ng_device_mod_event(module_t, int, void *);
static ng_constructor_t ng_device_constructor;
static ng_rcvmsg_t ng_device_rcvmsg;
static ng_shutdown_t ng_device_shutdown;
static ng_newhook_t ng_device_newhook;
static ng_rcvdata_t ng_device_rcvdata;
static ng_disconnect_t ng_device_disconnect;
/* List of commands and how to convert arguments to/from ASCII. */
static const struct ng_cmdlist ng_device_cmds[] = {
{
NGM_DEVICE_COOKIE,
NGM_DEVICE_GET_DEVNAME,
"getdevname",
NULL,
&ng_parse_string_type
},
{
NGM_DEVICE_COOKIE,
NGM_DEVICE_ETHERALIGN,
"etheralign",
NULL,
NULL
},
{ 0 }
};
/* Netgraph type */
static struct ng_type ngd_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_DEVICE_NODE_TYPE,
.mod_event = ng_device_mod_event,
.constructor = ng_device_constructor,
.rcvmsg = ng_device_rcvmsg,
.shutdown = ng_device_shutdown,
.newhook = ng_device_newhook,
.rcvdata = ng_device_rcvdata,
.disconnect = ng_device_disconnect,
.cmdlist = ng_device_cmds,
};
NETGRAPH_INIT(device, &ngd_typestruct);
/* per node data */
struct ngd_private {
struct ifqueue readq;
struct ng_node *node;
struct ng_hook *hook;
struct cdev *ngddev;
struct mtx ngd_mtx;
int unit;
int ether_align;
uint16_t flags;
#define NGDF_OPEN 0x0001
#define NGDF_RWAIT 0x0002
};
typedef struct ngd_private *priv_p;
/* unit number allocator entity */
static struct unrhdr *ngd_unit;
/* Maximum number of NGD devices */
#define MAX_NGD 999
static d_close_t ngdclose;
static d_open_t ngdopen;
static d_read_t ngdread;
static d_write_t ngdwrite;
#if 0
static d_ioctl_t ngdioctl;
#endif
static d_poll_t ngdpoll;
static struct cdevsw ngd_cdevsw = {
.d_version = D_VERSION,
.d_open = ngdopen,
.d_close = ngdclose,
.d_read = ngdread,
.d_write = ngdwrite,
#if 0
.d_ioctl = ngdioctl,
#endif
.d_poll = ngdpoll,
.d_name = NG_DEVICE_DEVNAME,
};
/******************************************************************************
* Netgraph methods
******************************************************************************/
/*
* Handle loading and unloading for this node type.
*/
static int
ng_device_mod_event(module_t mod, int event, void *data)
{
int error = 0;
switch (event) {
case MOD_LOAD:
ngd_unit = new_unrhdr(0, MAX_NGD, NULL);
break;
case MOD_UNLOAD:
delete_unrhdr(ngd_unit);
break;
default:
error = EOPNOTSUPP;
break;
}
return (error);
}
/*
* create new node
*/
static int
ng_device_constructor(node_p node)
{
priv_p priv;
DBG;
priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO);
/* Allocate unit number */
priv->unit = alloc_unr(ngd_unit);
/* Initialize mutexes and queue */
mtx_init(&priv->ngd_mtx, "ng_device", NULL, MTX_DEF);
mtx_init(&priv->readq.ifq_mtx, "ng_device queue", NULL, MTX_DEF);
IFQ_SET_MAXLEN(&priv->readq, ifqmaxlen);
/* Link everything together */
NG_NODE_SET_PRIVATE(node, priv);
priv->node = node;
priv->ngddev = make_dev(&ngd_cdevsw, priv->unit, UID_ROOT,
GID_WHEEL, 0600, NG_DEVICE_DEVNAME "%d", priv->unit);
if(priv->ngddev == NULL) {
printf("%s(): make_dev() failed\n",__func__);
mtx_destroy(&priv->ngd_mtx);
mtx_destroy(&priv->readq.ifq_mtx);
free_unr(ngd_unit, priv->unit);
free(priv, M_NETGRAPH);
return(EINVAL);
}
/* XXX: race here? */
priv->ngddev->si_drv1 = priv;
/* Give this node the same name as the device (if possible). */
if (ng_name_node(node, devtoname(priv->ngddev)) != 0)
log(LOG_WARNING, "%s: can't acquire netgraph name\n",
devtoname(priv->ngddev));
return(0);
}
/*
* Process control message.
*/
static int
ng_device_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = NG_NODE_PRIVATE(node);
struct ng_mesg *msg;
struct ng_mesg *resp = NULL;
const char *dn;
int error = 0;
NGI_GET_MSG(item, msg);
if (msg->header.typecookie == NGM_DEVICE_COOKIE) {
switch (msg->header.cmd) {
case NGM_DEVICE_GET_DEVNAME:
/* XXX: Fix when MAX_NGD us bigger */
NG_MKRESPONSE(resp, msg,
strlen(NG_DEVICE_DEVNAME) + 4, M_NOWAIT);
if (resp == NULL)
ERROUT(ENOMEM);
dn = devtoname(priv->ngddev);
strlcpy((char *)resp->data, dn, strlen(dn) + 1);
break;
case NGM_DEVICE_ETHERALIGN:
/* Use ETHER_ALIGN on arches that require it. */
#ifndef __NO_STRICT_ALIGNMENT
priv->ether_align = ETHER_ALIGN;
#endif
break;
default:
error = EINVAL;
break;
}
} else
error = EINVAL;
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Accept incoming hook. We support only one hook per node.
*/
static int
ng_device_newhook(node_p node, hook_p hook, const char *name)
{
priv_p priv = NG_NODE_PRIVATE(node);
DBG;
/* We have only one hook per node */
if (priv->hook != NULL)
return (EISCONN);
priv->hook = hook;
return(0);
}
/*
* Receive data from hook, write it to device.
*/
static int
ng_device_rcvdata(hook_p hook, item_p item)
{
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct mbuf *m;
DBG;
NGI_GET_M(item, m);
NG_FREE_ITEM(item);
IF_LOCK(&priv->readq);
if (_IF_QFULL(&priv->readq)) {
IF_UNLOCK(&priv->readq);
NG_FREE_M(m);
return (ENOBUFS);
}
_IF_ENQUEUE(&priv->readq, m);
IF_UNLOCK(&priv->readq);
mtx_lock(&priv->ngd_mtx);
if (priv->flags & NGDF_RWAIT) {
priv->flags &= ~NGDF_RWAIT;
wakeup(priv);
}
mtx_unlock(&priv->ngd_mtx);
return(0);
}
/*
* Removal of the hook destroys the node.
*/
static int
ng_device_disconnect(hook_p hook)
{
priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
DBG;
destroy_dev(priv->ngddev);
mtx_destroy(&priv->ngd_mtx);
IF_DRAIN(&priv->readq);
mtx_destroy(&(priv)->readq.ifq_mtx);
free_unr(ngd_unit, priv->unit);
free(priv, M_NETGRAPH);
ng_rmnode_self(NG_HOOK_NODE(hook));
return(0);
}
/*
* Node shutdown. Everything is already done in disconnect method.
*/
static int
ng_device_shutdown(node_p node)
{
NG_NODE_UNREF(node);
return (0);
}
/******************************************************************************
* Device methods
******************************************************************************/
/*
* the device is opened
*/
static int
ngdopen(struct cdev *dev, int flag, int mode, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
DBG;
mtx_lock(&priv->ngd_mtx);
priv->flags |= NGDF_OPEN;
mtx_unlock(&priv->ngd_mtx);
return(0);
}
/*
* the device is closed
*/
static int
ngdclose(struct cdev *dev, int flag, int mode, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
DBG;
mtx_lock(&priv->ngd_mtx);
priv->flags &= ~NGDF_OPEN;
mtx_unlock(&priv->ngd_mtx);
return(0);
}
#if 0 /*
* The ioctl is transformed into netgraph control message.
* We do not process them, yet.
*/
/*
* process ioctl
*
* they are translated into netgraph messages and passed on
*
*/
static int
ngdioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flag, struct thread *td)
{
struct ngd_softc *sc = &ngd_softc;
struct ngd_connection * connection = NULL;
struct ngd_connection * tmp;
int error = 0;
struct ng_mesg *msg;
struct ngd_param_s * datap;
DBG;
NG_MKMESSAGE(msg, NGM_DEVICE_COOKIE, cmd, sizeof(struct ngd_param_s),
M_NOWAIT);
if (msg == NULL) {
printf("%s(): msg == NULL\n",__func__);
goto nomsg;
}
/* pass the ioctl data into the ->data area */
datap = (struct ngd_param_s *)msg->data;
datap->p = addr;
NG_SEND_MSG_HOOK(error, sc->node, msg, connection->active_hook, 0);
if(error)
printf("%s(): NG_SEND_MSG_HOOK error: %d\n",__func__,error);
nomsg:
return(0);
}
#endif /* if 0 */
/*
* This function is called when a read(2) is done to our device.
* We process one mbuf from queue.
*/
static int
ngdread(struct cdev *dev, struct uio *uio, int flag)
{
priv_p priv = (priv_p )dev->si_drv1;
struct mbuf *m;
int len, error = 0;
DBG;
/* get an mbuf */
do {
IF_DEQUEUE(&priv->readq, m);
if (m == NULL) {
if (flag & IO_NDELAY)
return (EWOULDBLOCK);
mtx_lock(&priv->ngd_mtx);
priv->flags |= NGDF_RWAIT;
if ((error = msleep(priv, &priv->ngd_mtx,
PDROP | PCATCH | (PZERO + 1),
"ngdread", 0)) != 0)
return (error);
}
} while (m == NULL);
while (m && uio->uio_resid > 0 && error == 0) {
len = MIN(uio->uio_resid, m->m_len);
if (len != 0)
error = uiomove(mtod(m, void *), len, uio);
m = m_free(m);
}
if (m)
m_freem(m);
return (error);
}
/*
* This function is called when our device is written to.
* We read the data from userland into mbuf chain and pass it to the remote hook.
*
*/
static int
ngdwrite(struct cdev *dev, struct uio *uio, int flag)
{
struct epoch_tracker et;
priv_p priv = (priv_p )dev->si_drv1;
struct mbuf *m;
int error = 0;
DBG;
if (uio->uio_resid == 0)
return (0);
if (uio->uio_resid < 0 || uio->uio_resid > IP_MAXPACKET)
return (EIO);
m = m_uiotombuf(uio, M_NOWAIT, 0, priv->ether_align, M_PKTHDR);
if (m == NULL)
return (ENOBUFS);
NET_EPOCH_ENTER(et);
NG_SEND_DATA_ONLY(error, priv->hook, m);
NET_EPOCH_EXIT(et);
return (error);
}
/*
* we are being polled/selected
* check if there is data available for read
*/
static int
ngdpoll(struct cdev *dev, int events, struct thread *td)
{
priv_p priv = (priv_p )dev->si_drv1;
int revents = 0;
if (events & (POLLIN | POLLRDNORM) &&
!IFQ_IS_EMPTY(&priv->readq))
revents |= events & (POLLIN | POLLRDNORM);
return (revents);
}
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