freebsd-skq/sys/netgraph/ng_gif.c
Julian Elischer be4252b367 Slight cosmetic changes.
Also introduce a macro to be called by persistent nodes to signal their
persistence during shutdown to hide this mechanism from the node author.

Make node flags have a consistent style in naming.

Document the change.
2004-07-20 17:15:38 +00:00

595 lines
16 KiB
C

/*
* ng_gif.c
*
* Copyright 2001 The Aerospace Corporation. 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.
* 3. The name of The Aerospace Corporation may not be used to endorse or
* promote products derived from this software.
*
* THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``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 AEROSPACE CORPORATION 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.
*
*
* Copyright (c) 1996-2000 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.
*
* $FreeBSD$
*/
/*
* ng_gif(4) netgraph node type
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/errno.h>
#include <sys/syslog.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/route.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <net/if_gif.h>
#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_parse.h>
#include <netgraph/ng_gif.h>
#define IFP2NG(ifp) ((struct ng_node *)((struct gif_softc *)(ifp))->gif_netgraph)
/* Per-node private data */
struct private {
struct ifnet *ifp; /* associated interface */
hook_p lower; /* lower OR orphan hook connection */
u_char lowerOrphan; /* whether lower is lower or orphan */
};
typedef struct private *priv_p;
/* Functional hooks called from if_gif.c */
static void ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af);
static void ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af);
static void ng_gif_attach(struct ifnet *ifp);
static void ng_gif_detach(struct ifnet *ifp);
/* Other functions */
static void ng_gif_input2(node_p node, struct mbuf **mp, int af);
static int ng_gif_glue_af(struct mbuf **mp, int af);
static int ng_gif_rcv_lower(node_p node, struct mbuf *m);
/* Netgraph node methods */
static ng_constructor_t ng_gif_constructor;
static ng_rcvmsg_t ng_gif_rcvmsg;
static ng_shutdown_t ng_gif_shutdown;
static ng_newhook_t ng_gif_newhook;
static ng_connect_t ng_gif_connect;
static ng_rcvdata_t ng_gif_rcvdata;
static ng_disconnect_t ng_gif_disconnect;
static int ng_gif_mod_event(module_t mod, int event, void *data);
/* List of commands and how to convert arguments to/from ASCII */
static const struct ng_cmdlist ng_gif_cmdlist[] = {
{
NGM_GIF_COOKIE,
NGM_GIF_GET_IFNAME,
"getifname",
NULL,
&ng_parse_string_type
},
{
NGM_GIF_COOKIE,
NGM_GIF_GET_IFINDEX,
"getifindex",
NULL,
&ng_parse_int32_type
},
{ 0 }
};
static struct ng_type ng_gif_typestruct = {
.version = NG_ABI_VERSION,
.name = NG_GIF_NODE_TYPE,
.mod_event = ng_gif_mod_event,
.constructor = ng_gif_constructor,
.rcvmsg = ng_gif_rcvmsg,
.shutdown = ng_gif_shutdown,
.newhook = ng_gif_newhook,
.connect = ng_gif_connect,
.rcvdata = ng_gif_rcvdata,
.disconnect = ng_gif_disconnect,
.cmdlist = ng_gif_cmdlist,
};
MODULE_VERSION(ng_gif, 1);
MODULE_DEPEND(ng_gif, if_gif, 1,1,1);
NETGRAPH_INIT(gif, &ng_gif_typestruct);
/******************************************************************
GIF FUNCTION HOOKS
******************************************************************/
/*
* Handle a packet that has come in on an interface. We get to
* look at it here before any upper layer protocols do.
*
* NOTE: this function will get called at splimp()
*/
static void
ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af)
{
const node_p node = IFP2NG(ifp);
const priv_p priv = NG_NODE_PRIVATE(node);
/* If "lower" hook not connected, let packet continue */
if (priv->lower == NULL || priv->lowerOrphan)
return;
ng_gif_input2(node, mp, af);
}
/*
* Handle a packet that has come in on an interface, and which
* does not match any of our known protocols (an ``orphan'').
*
* NOTE: this function will get called at splimp()
*/
static void
ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af)
{
const node_p node = IFP2NG(ifp);
const priv_p priv = NG_NODE_PRIVATE(node);
/* If "orphan" hook not connected, let packet continue */
if (priv->lower == NULL || !priv->lowerOrphan) {
m_freem(m);
return;
}
ng_gif_input2(node, &m, af);
if (m != NULL)
m_freem(m);
}
/*
* Handle a packet that has come in on a gif interface.
* Attach the address family to the mbuf for later use.
*
* NOTE: this function will get called at splimp()
*/
static void
ng_gif_input2(node_p node, struct mbuf **mp, int af)
{
const priv_p priv = NG_NODE_PRIVATE(node);
int error;
/* Glue address family on */
if ((error = ng_gif_glue_af(mp, af)) != 0)
return;
/* Send out lower/orphan hook */
NG_SEND_DATA_ONLY(error, priv->lower, *mp);
*mp = NULL;
}
/*
* A new gif interface has been attached.
* Create a new node for it, etc.
*/
static void
ng_gif_attach(struct ifnet *ifp)
{
priv_p priv;
node_p node;
/* Create node */
KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
if (ng_make_node_common(&ng_gif_typestruct, &node) != 0) {
log(LOG_ERR, "%s: can't %s for %s\n",
__func__, "create node", ifp->if_xname);
return;
}
/* Allocate private data */
MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
if (priv == NULL) {
log(LOG_ERR, "%s: can't %s for %s\n",
__func__, "allocate memory", ifp->if_xname);
NG_NODE_UNREF(node);
return;
}
NG_NODE_SET_PRIVATE(node, priv);
priv->ifp = ifp;
IFP2NG(ifp) = node;
/* Try to give the node the same name as the interface */
if (ng_name_node(node, ifp->if_xname) != 0) {
log(LOG_WARNING, "%s: can't name node %s\n",
__func__, ifp->if_xname);
}
}
/*
* An interface is being detached.
* REALLY Destroy its node.
*/
static void
ng_gif_detach(struct ifnet *ifp)
{
const node_p node = IFP2NG(ifp);
priv_p priv;
if (node == NULL) /* no node (why not?), ignore */
return;
priv = NG_NODE_PRIVATE(node);
NG_NODE_REALLY_DIE(node); /* Force real removal of node */
/*
* We can't assume the ifnet is still around when we run shutdown
* So zap it now. XXX We HOPE that anything running at this time
* handles it (as it should in the non netgraph case).
*/
IFP2NG(ifp) = NULL;
priv->ifp = NULL; /* XXX race if interrupted an output packet */
ng_rmnode_self(node); /* remove all netgraph parts */
}
/*
* Optimization for gluing the address family onto
* the front of an incoming packet.
*/
static int
ng_gif_glue_af(struct mbuf **mp, int af)
{
struct mbuf *m = *mp;
int error = 0;
sa_family_t tmp_af;
tmp_af = (sa_family_t) af;
/*
* XXX: should try to bring back some of the optimizations from
* ng_ether.c
*/
/*
* Doing anything more is likely to get more
* expensive than it's worth..
* it's probable that everything else is in one
* big lump. The next node will do an m_pullup()
* for exactly the amount of data it needs and
* hopefully everything after that will not
* need one. So let's just use M_PREPEND.
*/
M_PREPEND(m, sizeof (tmp_af), M_DONTWAIT);
if (m == NULL) {
error = ENOBUFS;
goto done;
}
#if 0
copy:
#endif
/* Copy header and return (possibly new) mbuf */
*mtod(m, sa_family_t *) = tmp_af;
#if 0
bcopy((caddr_t)&tmp_af, mtod(m, sa_family_t *), sizeof(tmp_af));
#endif
done:
*mp = m;
return error;
}
/******************************************************************
NETGRAPH NODE METHODS
******************************************************************/
/*
* It is not possible or allowable to create a node of this type.
* Nodes get created when the interface is attached (or, when
* this node type's KLD is loaded).
*/
static int
ng_gif_constructor(node_p node)
{
return (EINVAL);
}
/*
* Check for attaching a new hook.
*/
static int
ng_gif_newhook(node_p node, hook_p hook, const char *name)
{
const priv_p priv = NG_NODE_PRIVATE(node);
u_char orphan = priv->lowerOrphan;
hook_p *hookptr;
/* Divert hook is an alias for lower */
if (strcmp(name, NG_GIF_HOOK_DIVERT) == 0)
name = NG_GIF_HOOK_LOWER;
/* Which hook? */
if (strcmp(name, NG_GIF_HOOK_LOWER) == 0) {
hookptr = &priv->lower;
orphan = 0;
} else if (strcmp(name, NG_GIF_HOOK_ORPHAN) == 0) {
hookptr = &priv->lower;
orphan = 1;
} else
return (EINVAL);
/* Check if already connected (shouldn't be, but doesn't hurt) */
if (*hookptr != NULL)
return (EISCONN);
/* OK */
*hookptr = hook;
priv->lowerOrphan = orphan;
return (0);
}
/*
* Hooks are attached, adjust to force queueing.
* We don't really care which hook it is.
* they should all be queuing for outgoing data.
*/
static int
ng_gif_connect(hook_p hook)
{
NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook));
return (0);
}
/*
* Receive an incoming control message.
*/
static int
ng_gif_rcvmsg(node_p node, item_p item, hook_p lasthook)
{
const priv_p priv = 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_GIF_COOKIE:
switch (msg->header.cmd) {
case NGM_GIF_GET_IFNAME:
NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ + 1);
break;
case NGM_GIF_GET_IFINDEX:
NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
if (resp == NULL) {
error = ENOMEM;
break;
}
*((u_int32_t *)resp->data) = priv->ifp->if_index;
break;
default:
error = EINVAL;
break;
}
break;
default:
error = EINVAL;
break;
}
NG_RESPOND_MSG(error, node, item, resp);
NG_FREE_MSG(msg);
return (error);
}
/*
* Receive data on a hook.
*/
static int
ng_gif_rcvdata(hook_p hook, item_p item)
{
const node_p node = NG_HOOK_NODE(hook);
const priv_p priv = NG_NODE_PRIVATE(node);
struct mbuf *m;
NGI_GET_M(item, m);
NG_FREE_ITEM(item);
if (hook == priv->lower)
return ng_gif_rcv_lower(node, m);
panic("%s: weird hook", __func__);
}
/*
* Handle an mbuf received on the "lower" hook.
*/
static int
ng_gif_rcv_lower(node_p node, struct mbuf *m)
{
struct sockaddr dst;
const priv_p priv = NG_NODE_PRIVATE(node);
bzero(&dst, sizeof(dst));
/* Make sure header is fully pulled up */
if (m->m_pkthdr.len < sizeof(sa_family_t)) {
NG_FREE_M(m);
return (EINVAL);
}
if (m->m_len < sizeof(sa_family_t)
&& (m = m_pullup(m, sizeof(sa_family_t))) == NULL) {
return (ENOBUFS);
}
dst.sa_family = *mtod(m, sa_family_t *);
m_adj(m, sizeof(sa_family_t));
/* Send it on its way */
/*
* XXX: gif_output only uses dst for the family and passes the
* fourth argument (rt) to in{,6}_gif_output which ignore it.
* If this changes ng_gif will probably break.
*/
return gif_output(priv->ifp, m, &dst, NULL);
}
/*
* Shutdown node. This resets the node but does not remove it
* unless the REALLY_DIE flag is set.
*/
static int
ng_gif_shutdown(node_p node)
{
const priv_p priv = NG_NODE_PRIVATE(node);
if (node->nd_flags & NGF_REALLY_DIE) {
/*
* WE came here because the gif interface is being destroyed,
* so stop being persistant.
* Actually undo all the things we did on creation.
* Assume the ifp has already been freed.
*/
NG_NODE_SET_PRIVATE(node, NULL);
FREE(priv, M_NETGRAPH);
NG_NODE_UNREF(node); /* free node itself */
return (0);
}
NG_NODE_REVIVE(node); /* Signal ng_rmnode we are persisant */
return (0);
}
/*
* Hook disconnection.
*/
static int
ng_gif_disconnect(hook_p hook)
{
const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
if (hook == priv->lower) {
priv->lower = NULL;
priv->lowerOrphan = 0;
} else
panic("%s: weird hook", __func__);
if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
ng_rmnode_self(NG_HOOK_NODE(hook)); /* reset node */
return (0);
}
/******************************************************************
INITIALIZATION
******************************************************************/
/*
* Handle loading and unloading for this node type.
*/
static int
ng_gif_mod_event(module_t mod, int event, void *data)
{
struct ifnet *ifp;
int error = 0;
int s;
s = splnet();
switch (event) {
case MOD_LOAD:
/* Register function hooks */
if (ng_gif_attach_p != NULL) {
error = EEXIST;
break;
}
ng_gif_attach_p = ng_gif_attach;
ng_gif_detach_p = ng_gif_detach;
ng_gif_input_p = ng_gif_input;
ng_gif_input_orphan_p = ng_gif_input_orphan;
/* Create nodes for any already-existing gif interfaces */
IFNET_RLOCK();
TAILQ_FOREACH(ifp, &ifnet, if_link) {
if (ifp->if_type == IFT_GIF)
ng_gif_attach(ifp);
}
IFNET_RUNLOCK();
break;
case MOD_UNLOAD:
/*
* Note that the base code won't try to unload us until
* all nodes have been removed, and that can't happen
* until all gif interfaces are destroyed. In any
* case, we know there are no nodes left if the action
* is MOD_UNLOAD, so there's no need to detach any nodes.
*
* XXX: what about manual unloads?!?
*/
/* Unregister function hooks */
ng_gif_attach_p = NULL;
ng_gif_detach_p = NULL;
ng_gif_input_p = NULL;
ng_gif_input_orphan_p = NULL;
break;
default:
error = EOPNOTSUPP;
break;
}
splx(s);
return (error);
}