FreeBSD-5.3/sys/netgraph/ng_tee.c
/*
* ng_tee.c
*
* Copyright (c) 1996-1999 Whistle Communications, Inc.
* All rights reserved.
*
* Subject to the following obligations and disclaimer of warranty, use and
* redistribution of this software, in source or object code forms, with or
* without modifications are expressly permitted by Whistle Communications;
* provided, however, that:
* 1. Any and all reproductions of the source or object code must include the
* copyright notice above and the following disclaimer of warranties; and
* 2. No rights are granted, in any manner or form, to use Whistle
* Communications, Inc. trademarks, including the mark "WHISTLE
* COMMUNICATIONS" on advertising, endorsements, or otherwise except as
* such appears in the above copyright notice or in the software.
*
* THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
* TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
* REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
* INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
* WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
* REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
* SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
* IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
* RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
* WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
* PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER 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 WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
* OF SUCH DAMAGE.
*
* Author: Julian Elischer <julian@freebsd.org>
*
* $FreeBSD: src/sys/netgraph/ng_tee.c,v 1.31 2004/06/26 22:24:16 julian Exp $
* $Whistle: ng_tee.c,v 1.18 1999/11/01 09:24:52 julian Exp $
*/
/*
* This node is like the tee(1) command and is useful for ``snooping.''
* It has 4 hooks: left, right, left2right, and right2left. Data
* entering from the right is passed to the left and duplicated on
* right2left, and data entering from the left is passed to the right
* and duplicated on left2right. Data entering from left2right is
* sent to left, and data from right2left to right.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_tee.h>
/* Per hook info */
struct hookinfo {
hook_p hook;
struct ng_tee_hookstat stats;
};
/* Per node info */
struct privdata {
node_p node;
struct hookinfo left;
struct hookinfo right;
struct hookinfo left2right;
struct hookinfo right2left;
};
typedef struct privdata *sc_p;
/* Netgraph methods */
static ng_constructor_t ngt_constructor;
static ng_rcvmsg_t ngt_rcvmsg;
static ng_close_t ngt_close;
static ng_shutdown_t ngt_shutdown;
static ng_newhook_t ngt_newhook;
static ng_rcvdata_t ngt_rcvdata;
static ng_disconnect_t ngt_disconnect;
/* Parse type for struct ng_tee_hookstat */
static const struct ng_parse_struct_field ng_tee_hookstat_type_fields[]
= NG_TEE_HOOKSTAT_INFO;
static const struct ng_parse_type ng_tee_hookstat_type = {
&ng_parse_struct_type,
&ng_tee_hookstat_type_fields
};
/* Parse type for struct ng_tee_stats */
static const struct ng_parse_struct_field ng_tee_stats_type_fields[]
= NG_TEE_STATS_INFO(&ng_tee_hookstat_type);
static const struct ng_parse_type ng_tee_stats_type = {
&ng_parse_struct_type,
&ng_tee_stats_type_fields
};
/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_tee_cmds[] = {
{
NGM_TEE_COOKIE,
NGM_TEE_GET_STATS,
"getstats",
NULL,
&ng_tee_stats_type
},
{
NGM_TEE_COOKIE,
NGM_TEE_CLR_STATS,
"clrstats",
NULL,
NULL
},
{
NGM_TEE_COOKIE,
NGM_TEE_GETCLR_STATS,
"getclrstats",
NULL,
&ng_tee_stats_type
},
{ 0 }
};
/* Netgraph type descriptor */
static struct ng_type ng_tee_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_TEE_NODE_TYPE,
.constructor = ngt_constructor,
.rcvmsg = ngt_rcvmsg,
.close = ngt_close,
.shutdown = ngt_shutdown,
.newhook = ngt_newhook,
.rcvdata = ngt_rcvdata,
.disconnect = ngt_disconnect,
.cmdlist = ng_tee_cmds,
};
NETGRAPH_INIT(tee, &ng_tee_typestruct);
/*
* Node constructor
*/
static int
ngt_constructor(node_p node)
{
sc_p privdata;
MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT|M_ZERO);
if (privdata == NULL)
return (ENOMEM);
NG_NODE_SET_PRIVATE(node, privdata);
privdata->node = node;
return (0);
}
/*
* Add a hook
*/
static int
ngt_newhook(node_p node, hook_p hook, const char *name)
{
const sc_p sc = NG_NODE_PRIVATE(node);
if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) {
sc->right.hook = hook;
bzero(&sc->right.stats, sizeof(sc->right.stats));
NG_HOOK_SET_PRIVATE(hook, &sc->right);
} else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) {
sc->left.hook = hook;
bzero(&sc->left.stats, sizeof(sc->left.stats));
NG_HOOK_SET_PRIVATE(hook, &sc->left);
} else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) {
sc->right2left.hook = hook;
bzero(&sc->right2left.stats, sizeof(sc->right2left.stats));
NG_HOOK_SET_PRIVATE(hook, &sc->right2left);
} else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) {
sc->left2right.hook = hook;
bzero(&sc->left2right.stats, sizeof(sc->left2right.stats));
NG_HOOK_SET_PRIVATE(hook, &sc->left2right);
} else
return (EINVAL);
return (0);
}
/*
* Receive a control message
*/
static int
ngt_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const sc_p sc = NG_NODE_PRIVATE(node);
struct ng_mesg *resp = NULL;
int error = 0;
struct ng_mesg *msg;
NGI_GET_MSG(item, msg);
switch (msg->header.typecookie) {
case NGM_TEE_COOKIE:
switch (msg->header.cmd) {
case NGM_TEE_GET_STATS:
case NGM_TEE_CLR_STATS:
case NGM_TEE_GETCLR_STATS:
{
struct ng_tee_stats *stats;
if (msg->header.cmd != NGM_TEE_CLR_STATS) {
NG_MKRESPONSE(resp, msg,
sizeof(*stats), M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
goto done;
}
stats = (struct ng_tee_stats *)resp->data;
bcopy(&sc->right.stats, &stats->right,
sizeof(stats->right));
bcopy(&sc->left.stats, &stats->left,
sizeof(stats->left));
bcopy(&sc->right2left.stats, &stats->right2left,
sizeof(stats->right2left));
bcopy(&sc->left2right.stats, &stats->left2right,
sizeof(stats->left2right));
}
if (msg->header.cmd != NGM_TEE_GET_STATS) {
bzero(&sc->right.stats,
sizeof(sc->right.stats));
bzero(&sc->left.stats,
sizeof(sc->left.stats));
bzero(&sc->right2left.stats,
sizeof(sc->right2left.stats));
bzero(&sc->left2right.stats,
sizeof(sc->left2right.stats));
}
break;
}
default:
error = EINVAL;
break;
}
break;
case NGM_FLOW_COOKIE:
if (lasthook) {
if (lasthook == sc->left.hook) {
if (sc->right.hook) {
NGI_MSG(item) = msg;
NG_FWD_ITEM_HOOK(error, item,
sc->right.hook);
return (error);
}
} else {
if (sc->left.hook) {
NGI_MSG(item) = msg;
NG_FWD_ITEM_HOOK(error, item,
sc->left.hook);
return (error);
}
}
}
break;
default:
error = EINVAL;
break;
}
done:
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive data on a hook
*
* If data comes in the right link send a copy out right2left, and then
* send the original onwards out through the left link.
* Do the opposite for data coming in from the left link.
* Data coming in right2left or left2right is forwarded
* on through the appropriate destination hook as if it had come
* from the other side.
*/
static int
ngt_rcvdata(hook_p hook, item_p item)
{
const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook);
struct hookinfo *dest;
struct hookinfo *dup;
int error = 0;
struct mbuf *m;
m = NGI_M(item);
/* Which hook? */
if (hinfo == &sc->left) {
dup = &sc->left2right;
dest = &sc->right;
} else if (hinfo == &sc->right) {
dup = &sc->right2left;
dest = &sc->left;
} else if (hinfo == &sc->right2left) {
dup = NULL;
dest = &sc->right;
} else if (hinfo == &sc->left2right) {
dup = NULL;
dest = &sc->left;
} else {
panic("%s: no hook!", __func__);
#ifdef RESTARTABLE_PANICS
return(EINVAL);
#endif
}
/* Update stats on incoming hook */
hinfo->stats.inOctets += m->m_pkthdr.len;
hinfo->stats.inFrames++;
/*
* Don't make a copy if only the dup hook exists.
*/
if ((dup && dup->hook) && (dest->hook == NULL)) {
dest = dup;
dup = NULL;
}
/* Duplicate packet if requried */
if (dup && dup->hook) {
struct mbuf *m2;
/* Copy packet (failure will not stop the original)*/
m2 = m_dup(m, M_DONTWAIT);
if (m2) {
/* Deliver duplicate */
dup->stats.outOctets += m->m_pkthdr.len;
dup->stats.outFrames++;
NG_SEND_DATA_ONLY(error, dup->hook, m2);
}
}
/* Deliver frame out destination hook */
if (dest->hook) {
dest->stats.outOctets += m->m_pkthdr.len;
dest->stats.outFrames++;
NG_FWD_ITEM_HOOK(error, item, dest->hook);
} else
NG_FREE_ITEM(item);
return (error);
}
/*
* We are going to be shut down soon
*
* If we have both a left and right hook, then we probably want to extricate
* ourselves and leave the two peers still linked to each other. Otherwise we
* should just shut down as a normal node would.
*/
static int
ngt_close(node_p node)
{
const sc_p privdata = NG_NODE_PRIVATE(node);
if (privdata->left.hook && privdata->right.hook)
ng_bypass(privdata->left.hook, privdata->right.hook);
return (0);
}
/*
* Shutdown processing
*/
static int
ngt_shutdown(node_p node)
{
const sc_p privdata = NG_NODE_PRIVATE(node);
NG_NODE_SET_PRIVATE(node, NULL);
NG_NODE_UNREF(privdata->node);
FREE(privdata, M_NETGRAPH);
return (0);
}
/*
* Hook disconnection
*/
static int
ngt_disconnect(hook_p hook)
{
struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook);
KASSERT(hinfo != NULL, ("%s: null info", __func__));
hinfo->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);
}