/*
* Copyright (C) 2013 Michael Brown <mbrown@fensystems.co.uk>.
*
* This program 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 of the
* License, or any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*
* You can also choose to distribute this program under the terms of
* the Unmodified Binary Distribution Licence (as given in the file
* COPYING.UBDL), provided that you have satisfied its requirements.
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <byteswap.h>
#include <ipxe/refcnt.h>
#include <ipxe/list.h>
#include <ipxe/iobuf.h>
#include <ipxe/tcpip.h>
#include <ipxe/icmp.h>
#include <ipxe/interface.h>
#include <ipxe/xfer.h>
#include <ipxe/open.h>
#include <ipxe/netdevice.h>
#include <ipxe/ping.h>
/** @file
*
* ICMP ping protocol
*
*/
/**
* A ping connection
*
*/
struct ping_connection {
/** Reference counter */
struct refcnt refcnt;
/** List of ping connections */
struct list_head list;
/** Remote socket address */
struct sockaddr_tcpip peer;
/** Local port number */
uint16_t port;
/** Data transfer interface */
struct interface xfer;
};
/** List of registered ping connections */
static LIST_HEAD ( ping_conns );
/**
* Identify ping connection by local port number
*
* @v port Local port number
* @ret ping Ping connection, or NULL
*/
static struct ping_connection * ping_demux ( unsigned int port ) {
struct ping_connection *ping;
list_for_each_entry ( ping, &ping_conns, list ) {
if ( ping->port == port )
return ping;
}
return NULL;
}
/**
* Check if local port number is available
*
* @v port Local port number
* @ret port Local port number, or negative error
*/
static int ping_port_available ( int port ) {
return ( ping_demux ( port ) ? -EADDRINUSE : port );
}
/**
* Process ICMP ping reply
*
* @v iobuf I/O buffer
* @v st_src Source address
* @ret rc Return status code
*/
int ping_rx ( struct io_buffer *iobuf, struct sockaddr_tcpip *st_src ) {
struct icmp_echo *echo = iobuf->data;
struct ping_connection *ping;
struct xfer_metadata meta;
int rc;
/* Sanity check: should already have been checked by ICMP layer */
assert ( iob_len ( iobuf ) >= sizeof ( *echo ) );
/* Identify connection */
ping = ping_demux ( ntohs ( echo->ident ) );
DBGC ( ping, "PING %p reply id %#04x seq %#04x\n",
ping, ntohs ( echo->ident ), ntohs ( echo->sequence ) );
if ( ! ping ) {
rc = -ENOTCONN;
goto discard;
}
/* Strip header, construct metadata, and pass data to upper layer */
iob_pull ( iobuf, sizeof ( *echo ) );
memset ( &meta, 0, sizeof ( meta ) );
meta.src = ( ( struct sockaddr * ) st_src );
meta.flags = XFER_FL_ABS_OFFSET;
meta.offset = ntohs ( echo->sequence );
return xfer_deliver ( &ping->xfer, iob_disown ( iobuf ), &meta );
discard:
free_iob ( iobuf );
return rc;
}
/**
* Allocate I/O buffer for ping
*
* @v ping Ping connection
* @v len Payload size
* @ret iobuf I/O buffer, or NULL
*/
static struct io_buffer *
ping_alloc_iob ( struct ping_connection *ping __unused, size_t len ) {
size_t header_len;
struct io_buffer *iobuf;
header_len = ( MAX_LL_NET_HEADER_LEN + sizeof ( struct icmp_echo ) );
iobuf = alloc_iob ( header_len + len );
if ( iobuf )
iob_reserve ( iobuf, header_len );
return iobuf;
}
/**
* Deliver datagram as I/O buffer
*
* @v ping Ping connection
* @v iobuf I/O buffer
* @v meta Data transfer metadata
* @ret rc Return status code
*/
static int ping_deliver ( struct ping_connection *ping, struct io_buffer *iobuf,
struct xfer_metadata *meta ) {
struct icmp_echo *echo = iob_push ( iobuf, sizeof ( *echo ) );
int rc;
/* Construct header */
memset ( echo, 0, sizeof ( *echo ) );
echo->ident = htons ( ping->port );
echo->sequence = htons ( meta->offset );
/* Transmit echo request */
if ( ( rc = icmp_tx_echo_request ( iob_disown ( iobuf ),
&ping->peer ) ) != 0 ) {
DBGC ( ping, "PING %p could not transmit: %s\n",
ping, strerror ( rc ) );
return rc;
}
return 0;
}
/**
* Close ping connection
*
* @v ping Ping connection
* @v rc Reason for close
*/
static void ping_close ( struct ping_connection *ping, int rc ) {
/* Close data transfer interface */
intf_shutdown ( &ping->xfer, rc );
/* Remove from list of connections and drop list's reference */
list_del ( &ping->list );
ref_put ( &ping->refcnt );
DBGC ( ping, "PING %p closed\n", ping );
}
/** Ping data transfer interface operations */
static struct interface_operation ping_xfer_operations[] = {
INTF_OP ( xfer_deliver, struct ping_connection *, ping_deliver ),
INTF_OP ( xfer_alloc_iob, struct ping_connection *, ping_alloc_iob ),
INTF_OP ( intf_close, struct ping_connection *, ping_close ),
};
/** Ping data transfer interface descriptor */
static struct interface_descriptor ping_xfer_desc =
INTF_DESC ( struct ping_connection, xfer, ping_xfer_operations );
/**
* Open a ping connection
*
* @v xfer Data transfer interface
* @v peer Peer socket address
* @v local Local socket address, or NULL
* @ret rc Return status code
*/
static int ping_open ( struct interface *xfer, struct sockaddr *peer,
struct sockaddr *local ) {
struct sockaddr_tcpip *st_peer = ( struct sockaddr_tcpip * ) peer;
struct sockaddr_tcpip *st_local = ( struct sockaddr_tcpip * ) local;
struct ping_connection *ping;
int port;
int rc;
/* Allocate and initialise structure */
ping = zalloc ( sizeof ( *ping ) );
if ( ! ping ) {
rc = -ENOMEM;
goto err_alloc;
}
DBGC ( ping, "PING %p allocated\n", ping );
ref_init ( &ping->refcnt, NULL );
intf_init ( &ping->xfer, &ping_xfer_desc, &ping->refcnt );
memcpy ( &ping->peer, st_peer, sizeof ( ping->peer ) );
/* Bind to local port */
port = tcpip_bind ( st_local, ping_port_available );
if ( port < 0 ) {
rc = port;
DBGC ( ping, "PING %p could not bind: %s\n",
ping, strerror ( rc ) );
goto err_bind;
}
ping->port = port;
DBGC ( ping, "PING %p bound to id %#04x\n", ping, port );
/* Attach parent interface, transfer reference to connection
* list, and return
*/
intf_plug_plug ( &ping->xfer, xfer );
list_add ( &ping->list, &ping_conns );
return 0;
err_bind:
ref_put ( &ping->refcnt );
err_alloc:
return rc;
}
/** Ping IPv4 socket opener */
struct socket_opener ping_ipv4_socket_opener __socket_opener = {
.semantics = PING_SOCK_ECHO,
.family = AF_INET,
.open = ping_open,
};
/** Ping IPv6 socket opener */
struct socket_opener ping_ipv6_socket_opener __socket_opener = {
.semantics = PING_SOCK_ECHO,
.family = AF_INET6,
.open = ping_open,
};
/** Linkage hack */
int ping_sock_echo = PING_SOCK_ECHO;
