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/*
* Copyright (c) 1997-1998 University of Utah and the Flux Group.
* All rights reserved.
*
* This file is part of the Flux OSKit. The OSKit is free software, also known
* as "open source;" you can redistribute it and/or modify it under the terms
* of the GNU General Public License (GPL), version 2, as published by the Free
* Software Foundation (FSF). To explore alternate licensing terms, contact
* the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
*
* The OSKit is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GPL for more details. You should have
* received a copy of the GPL along with the OSKit; see the file COPYING. If
* not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
*/
/*
* Another netio example
*
* A simple unsafe packet filter which invokes a user-defined function
* on any incoming packet. The function decides whether the packet
* is to be pushed or not.
*/
#include <oskit/io/netio.h>
#include <oskit/c/string.h>
#include <oskit/c/stdlib.h>
#include <oskit/c/malloc.h>
#include <oskit/c/assert.h>
struct uspf_netio_impl {
oskit_netio_t ioi; /* COM I/O Interface */
unsigned count; /* reference count */
/* return 1 if packet if accepted */
int (*func)(void *frame, oskit_size_t pktsize);
oskit_netio_t *forward_to;
};
typedef struct uspf_netio_impl uspf_netio_impl_t;
/*
* Query a net I/O object for its interfaces.
*/
static OSKIT_COMDECL
net_query(oskit_netio_t *io, const oskit_iid_t *iid, void **out_ihandle)
{
struct uspf_netio_impl *po = (struct uspf_netio_impl *)io;
assert (po != NULL);
assert (po->count != 0);
if (memcmp(iid, &oskit_iunknown_iid, sizeof(*iid)) == 0 ||
memcmp(iid, &oskit_netio_iid, sizeof(*iid)) == 0) {
*out_ihandle = &po->ioi;
++po->count;
return 0;
}
*out_ihandle = NULL;
return OSKIT_E_NOINTERFACE;
}
/*
* Clone a reference to the netio interface
*/
static OSKIT_COMDECL_U
net_addref(oskit_netio_t *io)
{
struct uspf_netio_impl *po = (struct uspf_netio_impl *)io;
assert (po != NULL);
assert (po->count != 0);
return ++po->count;
}
/*
* Close ("release") a device.
*/
static OSKIT_COMDECL_U
net_release(oskit_netio_t *io)
{
struct uspf_netio_impl *po = (struct uspf_netio_impl *)io;
unsigned newcount;
assert (po != NULL);
assert (po->count != 0);
newcount = --po->count;
if (newcount == 0) {
free(po);
}
return newcount;
}
/*
* Receive a packet and forward it on to the callback function.
*/
static OSKIT_COMDECL
net_push(oskit_netio_t *io, oskit_bufio_t *b, oskit_size_t pkt_size)
{
struct uspf_netio_impl *po = (struct uspf_netio_impl *)io;
static unsigned char *frame;
oskit_error_t err, rc = 0;
assert (po != NULL);
assert (po->count != 0);
/* check to see if the bufio matches the filter */
err = oskit_bufio_map(b, (void **)&frame, 0, pkt_size);
/* XXX read in if map fails */
if (err)
return err;
/* check callback function */
if (po->func(frame, pkt_size)) {
/* matches, call the netio's push routine */
rc = oskit_netio_push(po->forward_to, b, pkt_size);
}
err = oskit_bufio_unmap(b, (void *)frame, 0, pkt_size);
assert(!err);
return rc;
}
/*
* vtable
*/
static struct oskit_netio_ops uspf_netio_impl_ops = {
net_query,
net_addref,
net_release,
net_push
};
/*
* create a unsafe packet filter
*/
oskit_netio_t *
oskit_netio_uspf_create(int (*func)(void *data, oskit_size_t pkt_size),
oskit_netio_t *push_on)
{
struct uspf_netio_impl *c;
c = (struct uspf_netio_impl *)malloc(sizeof(*c));
if (c == NULL)
return NULL;
c->ioi.ops = &uspf_netio_impl_ops;
c->count = 1;
c->func = func;
c->forward_to = push_on;
return &c->ioi;
}
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