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/*
* 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.
*/
/*
* Local host as a default server for fpm connection
*/
#define FPM_DEFAULT_IP (htonl (INADDR_LOOPBACK))
/*
* default port for fpm connections
*/
#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;
}
// tcp maximum range
#define TCP_MAX_PORT 65535
// tcp minimum range
#define TCP_MIN_PORT 1
#endif /* _FPM_H */