src/net/ping.c - ipxe - Git at Google

 /*
  * 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 socket opener */
 struct socket_opener ping_socket_opener __socket_opener = {
 	.semantics	= PING_SOCK_ECHO,
 	.open		= ping_open,
 };

 /** Linkage hack */
 int ping_sock_echo = PING_SOCK_ECHO;
	/*
	* 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 socket opener */
	struct socket_opener ping_socket_opener __socket_opener = {
	.semantics = PING_SOCK_ECHO,
	.open = ping_open,
	};

	/** Linkage hack */
	int ping_sock_echo = PING_SOCK_ECHO;