freebsd-nq/sys/netgraph/ng_tee.c
Julian Elischer 589f6ed8ce Divorce the kernel binary ABI version number from the message
format version number. (userland programs should not need to be
recompiled when the netgraph kernel internal ABI is changed.

Also fix modules that don;t handle the fact that a caller may not supply
a return message pointer. (benign at the moment because the calling code
checks, but that will change)
2000-12-18 20:03:32 +00:00

386 lines
10 KiB
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>
*
* $FreeBSD$
* $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 right, and data from right2left to left.
*/
#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_shutdown_t ngt_rmnode;
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_info
ng_tee_hookstat_type_info = NG_TEE_HOOKSTAT_INFO;
static const struct ng_parse_type ng_tee_hookstat_type = {
&ng_parse_struct_type,
&ng_tee_hookstat_type_info,
};
/* Parse type for struct ng_tee_stats */
static const struct ng_parse_struct_info
ng_tee_stats_type_info = 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_info,
};
/* 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 = {
NG_ABI_VERSION,
NG_TEE_NODE_TYPE,
NULL,
ngt_constructor,
ngt_rcvmsg,
ngt_rmnode,
ngt_newhook,
NULL,
NULL,
ngt_rcvdata,
ngt_disconnect,
ng_tee_cmds
};
NETGRAPH_INIT(tee, &ng_tee_typestruct);
/*
* Node constructor
*/
static int
ngt_constructor(node_p *nodep)
{
sc_p privdata;
int error = 0;
MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT|M_ZERO);
if (privdata == NULL)
return (ENOMEM);
if ((error = ng_make_node_common(&ng_tee_typestruct, nodep))) {
FREE(privdata, M_NETGRAPH);
return (error);
}
(*nodep)->private = privdata;
privdata->node = *nodep;
return (0);
}
/*
* Add a hook
*/
static int
ngt_newhook(node_p node, hook_p hook, const char *name)
{
const sc_p sc = node->private;
if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) {
sc->right.hook = hook;
bzero(&sc->right.stats, sizeof(sc->right.stats));
hook->private = &sc->right;
} else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) {
sc->left.hook = hook;
bzero(&sc->left.stats, sizeof(sc->left.stats));
hook->private = &sc->left;
} else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) {
sc->right2left.hook = hook;
bzero(&sc->right2left.stats, sizeof(sc->right2left.stats));
hook->private = &sc->right2left;
} else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) {
sc->left2right.hook = hook;
bzero(&sc->left2right.stats, sizeof(sc->left2right.stats));
hook->private = &sc->left2right;
} else
return (EINVAL);
return (0);
}
/*
* Receive a control message
*/
static int
ngt_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
struct ng_mesg **rptr, hook_p lasthook)
{
const sc_p sc = node->private;
struct ng_mesg *resp = NULL;
int error = 0;
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;
default:
error = EINVAL;
break;
}
if (rptr)
*rptr = resp;
else if (resp)
FREE(resp, M_NETGRAPH);
done:
FREE(msg, M_NETGRAPH);
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, struct mbuf *m, meta_p meta,
struct mbuf **ret_m, meta_p *ret_meta, struct ng_mesg **resp)
{
const sc_p sc = hook->node->private;
struct hookinfo *const hinfo = (struct hookinfo *) hook->private;
struct hookinfo *dest;
struct hookinfo *dup;
int error = 0;
/* 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->left;
} else if (hinfo == &sc->left2right) {
dup = NULL;
dest = &sc->right;
} else
panic("%s: no hook!", __FUNCTION__);
/* Update stats on incoming hook */
hinfo->stats.inOctets += m->m_pkthdr.len;
hinfo->stats.inFrames++;
/* Duplicate packet and meta info if requried */
if (dup != NULL) {
struct mbuf *m2;
meta_p meta2;
/* Copy packet */
m2 = m_dup(m, M_NOWAIT);
if (m2 == NULL) {
NG_FREE_DATA(m, meta);
return (ENOBUFS);
}
/* Copy meta info */
if (meta != NULL) {
MALLOC(meta2, meta_p,
meta->used_len, M_NETGRAPH, M_NOWAIT);
if (meta2 == NULL) {
m_freem(m2);
NG_FREE_DATA(m, meta);
return (ENOMEM);
}
bcopy(meta, meta2, meta->used_len);
meta2->allocated_len = meta->used_len;
} else
meta2 = NULL;
/* Deliver duplicate */
dup->stats.outOctets += m->m_pkthdr.len;
dup->stats.outFrames++;
NG_SEND_DATA(error, dup->hook, m2, meta2);
}
/* Deliver frame out destination hook */
dest->stats.outOctets += m->m_pkthdr.len;
dest->stats.outFrames++;
NG_SEND_DATA(error, dest->hook, m, meta);
return (0);
}
/*
* Shutdown processing
*
* This is tricky. 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.
*
* To keep the scope of info correct the routine to "extract" a node
* from two links is in ng_base.c.
*/
static int
ngt_rmnode(node_p node)
{
const sc_p privdata = node->private;
node->flags |= NG_INVALID;
if (privdata->left.hook && privdata->right.hook)
ng_bypass(privdata->left.hook, privdata->right.hook);
ng_cutlinks(node);
ng_unname(node);
node->private = NULL;
ng_unref(privdata->node);
FREE(privdata, M_NETGRAPH);
return (0);
}
/*
* Hook disconnection
*/
static int
ngt_disconnect(hook_p hook)
{
struct hookinfo *const hinfo = (struct hookinfo *) hook->private;
KASSERT(hinfo != NULL, ("%s: null info", __FUNCTION__));
hinfo->hook = NULL;
if (hook->node->numhooks == 0)
ng_rmnode(hook->node);
return (0);
}