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//==========================================================================
//
// net/icmp.c
//
// Stand-alone ICMP networking support for RedBoot
//
//==========================================================================
// ####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later
// version.
//
// eCos 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 GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License
// along with eCos; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
//
// As a special exception, if other files instantiate templates or use
// macros or inline functions from this file, or you compile this file
// and link it with other works to produce a work based on this file,
// this file does not by itself cause the resulting work to be covered by
// the GNU General Public License. However the source code for this file
// must still be made available in accordance with section (3) of the GNU
// General Public License v2.
//
// This exception does not invalidate any other reasons why a work based
// on this file might be covered by the GNU General Public License.
// -------------------------------------------
// ####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s): gthomas
// Contributors: gthomas
// Date: 2000-07-14
// Purpose:
// Description:
//
// This code is part of RedBoot (tm).
//
//####DESCRIPTIONEND####
//
//==========================================================================
#include <net/net.h>
/*
* Handle ICMP packets.
*/
static void default_icmp_handler(pktbuf_t *pkt, ip_route_t *dest);
static icmp_handler_t icmp_handler = default_icmp_handler;
/*
* Install a user defined user_handler for incoming icmp packets.
* Returns zero if successful, -1 if the user_handler is already used.
*/
int
__icmp_install_listener(icmp_handler_t user_handler)
{
if (icmp_handler == user_handler) {
return -1;
}
icmp_handler = user_handler;
return 0;
}
/*
* Replace a user defined handler by the default handler.
*/
void
__icmp_remove_listener(void)
{
if (icmp_handler != default_icmp_handler) {
icmp_handler = default_icmp_handler;
}
}
/*
* ICMP entry point with an IP packet pkt and the destination dest a reply
* should be sent to.
*/
void
__icmp_handler(pktbuf_t *pkt, ip_route_t *dest)
{
(*icmp_handler)(pkt, dest);
BSPLOG(bsp_log("icmp: dest[%s] type[%d] seq[%d]\n",
inet_ntoa(pkt->ip_hdr->destination),
pkt->icmp_hdr->type,
pkt->icmp_hdr->seqnum));
__pktbuf_free(pkt);
}
/*
* The default ICMP handler only handles ICMP incoming echo request and
* outgoing echo reply.
*/
static void
default_icmp_handler(pktbuf_t *pkt, ip_route_t *dest)
{
word cksum;
if (pkt->icmp_hdr->type == ICMP_TYPE_ECHOREQUEST
&& pkt->icmp_hdr->code == 0
&& __sum((word *)pkt->icmp_hdr, pkt->pkt_bytes, 0) == 0) {
pkt->icmp_hdr->type = ICMP_TYPE_ECHOREPLY;
pkt->icmp_hdr->checksum = 0;
cksum = __sum((word *)pkt->icmp_hdr, pkt->pkt_bytes, 0);
pkt->icmp_hdr->checksum = htons(cksum);
__ip_send(pkt, IP_PROTO_ICMP, dest);
}
}
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