fpm/fpm.h - quagga - Gitiles

 /*
  * Public definitions pertaining to the Forwarding Plane Manager component.
  *
  * Permission is granted to use, copy, modify and/or distribute this
  * software under either one of the licenses below.
  *
  * Note that if you use other files from the Quagga tree directly or
  * indirectly, then the licenses in those files still apply.
  *
  * Please retain both licenses below when modifying this code in the
  * Quagga tree.
  *
  * Copyright (C) 2012 by Open Source Routing.
  * Copyright (C) 2012 by Internet Systems Consortium, Inc. ("ISC")
  */

 /*
  * License Option 1: GPL
  *
  * 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 (at your option)
  * 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.,
  * 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  */

 /*
  * License Option 2: ISC License
  *
  * Permission to use, copy, modify, and/or distribute this software
  * for any purpose with or without fee is hereby granted, provided
  * that the above copyright notice and this permission notice appear
  * in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
  * WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
  * AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
  * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
  * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */

 #ifndef _FPM_H
 #define _FPM_H

 /*
  * The Forwarding Plane Manager (FPM) is an optional component that
  * may be used in scenarios where the router has a forwarding path
  * that is distinct from the kernel, commonly a hardware-based fast
  * path. It is responsible for programming forwarding information
  * (such as routes and nexthops) in the fast path.
  *
  * In Quagga, the Routing Information Base is maintained in the
  * 'zebra' infrastructure daemon. Routing protocols communicate their
  * best routes to zebra, and zebra computes the best route across
  * protocols for each prefix. This latter information comprises the
  * bulk of the Forwarding Information Base.
  *
  * This header file defines a point-to-point interface using which
  * zebra can update the FPM about changes in routes. The communication
  * takes place over a stream socket. The FPM listens on a well-known
  * TCP port, and zebra initiates the connection.
  *
  * All messages sent over the connection start with a short FPM
  * header, fpm_msg_hdr_t. In the case of route add/delete messages,
  * the header is followed by a netlink message. Zebra should send a
  * complete copy of the forwarding table(s) to the FPM, including
  * routes that it may have picked up from the kernel.
  *
  * The FPM interface uses replace semantics. That is, if a 'route add'
  * message for a prefix is followed by another 'route add' message, the
  * information in the second message is complete by itself, and replaces
  * the information sent in the first message.
  *
  * If the connection to the FPM goes down for some reason, the client
  * (zebra) should send the FPM a complete copy of the forwarding
  * table(s) when it reconnects.
  */

 #define FPM_DEFAULT_PORT 2620

 /*
  * Largest message that can be sent to or received from the FPM.
  */
 #define FPM_MAX_MSG_LEN 4096

 /*
  * Header that precedes each fpm message to/from the FPM.
  */
 typedef struct fpm_msg_hdr_t_
 {
   /*
    * Protocol version.
    */
   uint8_t version;

   /*
    * Type of message, see below.
    */
   uint8_t msg_type;

   /*
    * Length of entire message, including the header, in network byte
    * order.
    *
    * Note that msg_len is rounded up to make sure that message is at
    * the desired alignment. This means that some payloads may need
    * padding at the end.
    */
   uint16_t msg_len;
 } fpm_msg_hdr_t;

 /*
  * The current version of the FPM protocol is 1.
  */
 #define FPM_PROTO_VERSION 1

 typedef enum fpm_msg_type_e_ {
   FPM_MSG_TYPE_NONE = 0,

   /*
    * Indicates that the payload is a completely formed netlink
    * message.
    */
   FPM_MSG_TYPE_NETLINK = 1,
 } fpm_msg_type_e;

 /*
  * The FPM message header is aligned to the same boundary as netlink
  * messages (4). This means that a netlink message does not need
  * padding when encapsulated in an FPM message.
  */
 #define FPM_MSG_ALIGNTO 4

 /*
  * fpm_msg_align
  *
  * Round up the given length to the desired alignment.
  */
 static inline size_t
 fpm_msg_align (size_t len)
 {
   return (len + FPM_MSG_ALIGNTO - 1) & ~(FPM_MSG_ALIGNTO - 1);
 }

 /*
  * The (rounded up) size of the FPM message header. This ensures that
  * the message payload always starts at an aligned address.
  */
 #define FPM_MSG_HDR_LEN (fpm_msg_align (sizeof (fpm_msg_hdr_t)))

 /*
  * fpm_data_len_to_msg_len
  *
  * The length value that should be placed in the msg_len field of the
  * header for a *payload* of size 'data_len'.
  */
 static inline size_t
 fpm_data_len_to_msg_len (size_t data_len)
 {
   return fpm_msg_align (data_len) + FPM_MSG_HDR_LEN;
 }

 /*
  * fpm_msg_data
  *
  * Pointer to the payload of the given fpm header.
  */
 static inline void *
 fpm_msg_data (fpm_msg_hdr_t *hdr)
 {
   return ((char*) hdr) + FPM_MSG_HDR_LEN;
 }

 /*
  * fpm_msg_len
  */
 static inline size_t
 fpm_msg_len (const fpm_msg_hdr_t *hdr)
 {
   return ntohs (hdr->msg_len);
 }

 /*
  * fpm_msg_data_len
  */
 static inline size_t
 fpm_msg_data_len (const fpm_msg_hdr_t *hdr)
 {
   return (fpm_msg_len (hdr) - FPM_MSG_HDR_LEN);
 }

 /*
  * fpm_msg_next
  *
  * Move to the next message in a buffer.
  */
 static inline fpm_msg_hdr_t *
 fpm_msg_next (fpm_msg_hdr_t *hdr, size_t *len)
 {
   size_t msg_len;

   msg_len = fpm_msg_len (hdr);

   if (len) {
     if (*len < msg_len)
       {
 	assert(0);
 	return NULL;
       }
     *len -= msg_len;
   }

   return (fpm_msg_hdr_t *) (((char*) hdr) + msg_len);
 }

 /*
  * fpm_msg_hdr_ok
  *
  * Returns TRUE if a message header looks well-formed.
  */
 static inline int
 fpm_msg_hdr_ok (const fpm_msg_hdr_t *hdr)
 {
   size_t msg_len;

   if (hdr->msg_type == FPM_MSG_TYPE_NONE)
     return 0;

   msg_len = fpm_msg_len (hdr);

   if (msg_len < FPM_MSG_HDR_LEN || msg_len > FPM_MAX_MSG_LEN)
     return 0;

   if (fpm_msg_align (msg_len) != msg_len)
     return 0;

   return 1;
 }

 /*
  * fpm_msg_ok
  *
  * Returns TRUE if a message looks well-formed.
  *
  * @param len The length in bytes from 'hdr' to the end of the buffer.
  */
 static inline int
 fpm_msg_ok (const fpm_msg_hdr_t *hdr, size_t len)
 {
   if (len < FPM_MSG_HDR_LEN)
     return 0;

   if (!fpm_msg_hdr_ok (hdr))
     return 0;

   if (fpm_msg_len (hdr) > len)
     return 0;

   return 1;
 }

 #endif /* _FPM_H */
	/*
	* Public definitions pertaining to the Forwarding Plane Manager component.
	*
	* Permission is granted to use, copy, modify and/or distribute this
	* software under either one of the licenses below.
	*
	* Note that if you use other files from the Quagga tree directly or
	* indirectly, then the licenses in those files still apply.
	*
	* Please retain both licenses below when modifying this code in the
	* Quagga tree.
	*
	* Copyright (C) 2012 by Open Source Routing.
	* Copyright (C) 2012 by Internet Systems Consortium, Inc. ("ISC")
	*/

	/*
	* License Option 1: GPL
	*
	* 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 (at your option)
	* 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.,
	* 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	*/

	/*
	* License Option 2: ISC License
	*
	* Permission to use, copy, modify, and/or distribute this software
	* for any purpose with or without fee is hereby granted, provided
	* that the above copyright notice and this permission notice appear
	* in all copies.
	*
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
	* WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
	* WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
	* AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
	* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
	* OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
	* NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
	* CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	*/

	#ifndef _FPM_H
	#define _FPM_H

	/*
	* The Forwarding Plane Manager (FPM) is an optional component that
	* may be used in scenarios where the router has a forwarding path
	* that is distinct from the kernel, commonly a hardware-based fast
	* path. It is responsible for programming forwarding information
	* (such as routes and nexthops) in the fast path.
	*
	* In Quagga, the Routing Information Base is maintained in the
	* 'zebra' infrastructure daemon. Routing protocols communicate their
	* best routes to zebra, and zebra computes the best route across
	* protocols for each prefix. This latter information comprises the
	* bulk of the Forwarding Information Base.
	*
	* This header file defines a point-to-point interface using which
	* zebra can update the FPM about changes in routes. The communication
	* takes place over a stream socket. The FPM listens on a well-known
	* TCP port, and zebra initiates the connection.
	*
	* All messages sent over the connection start with a short FPM
	* header, fpm_msg_hdr_t. In the case of route add/delete messages,
	* the header is followed by a netlink message. Zebra should send a
	* complete copy of the forwarding table(s) to the FPM, including
	* routes that it may have picked up from the kernel.
	*
	* The FPM interface uses replace semantics. That is, if a 'route add'
	* message for a prefix is followed by another 'route add' message, the
	* information in the second message is complete by itself, and replaces
	* the information sent in the first message.
	*
	* If the connection to the FPM goes down for some reason, the client
	* (zebra) should send the FPM a complete copy of the forwarding
	* table(s) when it reconnects.
	*/

	#define FPM_DEFAULT_PORT 2620

	/*
	* Largest message that can be sent to or received from the FPM.
	*/
	#define FPM_MAX_MSG_LEN 4096

	/*
	* Header that precedes each fpm message to/from the FPM.
	*/
	typedef struct fpm_msg_hdr_t_
	{
	/*
	* Protocol version.
	*/
	uint8_t version;

	/*
	* Type of message, see below.
	*/
	uint8_t msg_type;

	/*
	* Length of entire message, including the header, in network byte
	* order.
	*
	* Note that msg_len is rounded up to make sure that message is at
	* the desired alignment. This means that some payloads may need
	* padding at the end.
	*/
	uint16_t msg_len;
	} fpm_msg_hdr_t;

	/*
	* The current version of the FPM protocol is 1.
	*/
	#define FPM_PROTO_VERSION 1

	typedef enum fpm_msg_type_e_ {
	FPM_MSG_TYPE_NONE = 0,

	/*
	* Indicates that the payload is a completely formed netlink
	* message.
	*/
	FPM_MSG_TYPE_NETLINK = 1,
	} fpm_msg_type_e;

	/*
	* The FPM message header is aligned to the same boundary as netlink
	* messages (4). This means that a netlink message does not need
	* padding when encapsulated in an FPM message.
	*/
	#define FPM_MSG_ALIGNTO 4

	/*
	* fpm_msg_align
	*
	* Round up the given length to the desired alignment.
	*/
	static inline size_t
	fpm_msg_align (size_t len)
	{
	return (len + FPM_MSG_ALIGNTO - 1) & ~(FPM_MSG_ALIGNTO - 1);
	}

	/*
	* The (rounded up) size of the FPM message header. This ensures that
	* the message payload always starts at an aligned address.
	*/
	#define FPM_MSG_HDR_LEN (fpm_msg_align (sizeof (fpm_msg_hdr_t)))

	/*
	* fpm_data_len_to_msg_len
	*
	* The length value that should be placed in the msg_len field of the
	* header for a payload of size 'data_len'.
	*/
	static inline size_t
	fpm_data_len_to_msg_len (size_t data_len)
	{
	return fpm_msg_align (data_len) + FPM_MSG_HDR_LEN;
	}

	/*
	* fpm_msg_data
	*
	* Pointer to the payload of the given fpm header.
	*/
	static inline void *
	fpm_msg_data (fpm_msg_hdr_t *hdr)
	{
	return ((char*) hdr) + FPM_MSG_HDR_LEN;
	}

	/*
	* fpm_msg_len
	*/
	static inline size_t
	fpm_msg_len (const fpm_msg_hdr_t *hdr)
	{
	return ntohs (hdr->msg_len);
	}

	/*
	* fpm_msg_data_len
	*/
	static inline size_t
	fpm_msg_data_len (const fpm_msg_hdr_t *hdr)
	{
	return (fpm_msg_len (hdr) - FPM_MSG_HDR_LEN);
	}

	/*
	* fpm_msg_next
	*
	* Move to the next message in a buffer.
	*/
	static inline fpm_msg_hdr_t *
	fpm_msg_next (fpm_msg_hdr_t hdr, size_t len)
	{
	size_t msg_len;

	msg_len = fpm_msg_len (hdr);

	if (len) {
	if (*len < msg_len)
	{
	assert(0);
	return NULL;
	}
	*len -= msg_len;
	}

	return (fpm_msg_hdr_t ) (((char) hdr) + msg_len);
	}

	/*
	* fpm_msg_hdr_ok
	*
	* Returns TRUE if a message header looks well-formed.
	*/
	static inline int
	fpm_msg_hdr_ok (const fpm_msg_hdr_t *hdr)
	{
	size_t msg_len;

	if (hdr->msg_type == FPM_MSG_TYPE_NONE)
	return 0;

	msg_len = fpm_msg_len (hdr);

	if (msg_len < FPM_MSG_HDR_LEN \|\| msg_len > FPM_MAX_MSG_LEN)
	return 0;

	if (fpm_msg_align (msg_len) != msg_len)
	return 0;

	return 1;
	}

	/*
	* fpm_msg_ok
	*
	* Returns TRUE if a message looks well-formed.
	*
	* @param len The length in bytes from 'hdr' to the end of the buffer.
	*/
	static inline int
	fpm_msg_ok (const fpm_msg_hdr_t *hdr, size_t len)
	{
	if (len < FPM_MSG_HDR_LEN)
	return 0;

	if (!fpm_msg_hdr_ok (hdr))
	return 0;

	if (fpm_msg_len (hdr) > len)
	return 0;

	return 1;
	}

	#endif /* _FPM_H */