diff --git a/include/freeDiameter/libfdcore.h b/include/freeDiameter/libfdcore.h
new file mode 100644
index 0000000..a28a542
--- /dev/null
+++ b/include/freeDiameter/libfdcore.h
@@ -0,0 +1,1211 @@
+/*********************************************************************************************************
+* Software License Agreement (BSD License)                                                               *
+* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
+*													 *
+* Copyright (c) 2016, WIDE Project and NICT								 *
+* All rights reserved.											 *
+* 													 *
+* Redistribution and use of this software in source and binary forms, with or without modification, are  *
+* permitted provided that the following conditions are met:						 *
+* 													 *
+* * Redistributions of source code must retain the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer.										 *
+*    													 *
+* * Redistributions in binary form must reproduce the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer in the documentation and/or other						 *
+*   materials provided with the distribution.								 *
+* 													 *
+* * Neither the name of the WIDE Project or NICT nor the 						 *
+*   names of its contributors may be used to endorse or 						 *
+*   promote products derived from this software without 						 *
+*   specific prior written permission of WIDE Project and 						 *
+*   NICT.												 *
+* 													 *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
+* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
+* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 	 *
+* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
+* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF   *
+* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.								 *
+*********************************************************************************************************/
+
+#ifndef _LIBFDCORE_H
+#define _LIBFDCORE_H
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <freeDiameter/libfdproto.h>
+#include <gnutls/gnutls.h>
+#include <gnutls/x509.h>
+
+/* GNUTLS version */
+#ifndef GNUTLS_VERSION
+#define GNUTLS_VERSION LIBGNUTLS_VERSION
+#endif /* GNUTLS_VERSION */
+
+/* GNUTLS calls debug level */
+#ifndef GNUTLS_DBG_LEVEL
+#define GNUTLS_DBG_LEVEL ANNOYING
+#endif /* GNUTLS_DBG_LEVEL */
+
+
+/* Check the return value of a GNUTLS function, log and propagate */
+#define CHECK_GNUTLS_GEN( faillevel, __call__, __fallback__  ) { 					\
+		CHECK_PRELUDE(__call__);								\
+		if (__ret__ < 0) {									\
+			LOG(faillevel, "TLS ERROR: in '%s' :\t%s",  #__call__ ,  gnutls_strerror(__ret__)); \
+			__fallback__;									\
+		}											\
+}
+
+/* we use this macro to help debugging gnutls usage issues -- just change the content to display what you need */
+#define GNUTLS_TRACE( __call__) {					\
+	TRACE_CALL("Check: %s", #__call__ );				\
+	(__call__);							\
+}
+
+
+#ifndef EXCLUDE_DEPRECATED
+/* Macro for transition, replace with CHECK_GNUTLS_GEN */
+#define CHECK_GNUTLS_DO( __call__, __fallback__ )	\
+	CHECK_GNUTLS_GEN( FD_LOG_ERROR, __call__, __fallback__  )
+
+#endif /* EXCLUDE_DEPRECATED */
+
+
+/*============================================================*/
+/*                      INITIALIZATION                        */
+/*============================================================*/
+
+
+/* Initialize the libfdcore internals. This also initializes libfdproto */
+int fd_core_initialize(void);
+
+/* A string describing the version of the library */
+extern const char fd_core_version[];
+
+/* Parse the freeDiameter.conf configuration file, load the extensions */
+int fd_core_parseconf(const char * conffile);
+
+/* Start the server & client threads */
+int fd_core_start(void);
+
+/* Block until the framework has completed its initialization -- useful for extensions */
+int fd_core_waitstartcomplete(void);
+
+/* Initialize shutdown of the framework */
+int fd_core_shutdown(void);
+
+/* Wait for the shutdown to be complete -- this should always be called after fd_core_shutdown */
+int fd_core_wait_shutdown_complete(void);
+
+
+/*============================================================*/
+/*                          CONFIG                            */
+/*============================================================*/
+
+/* Structure to hold the configuration of the freeDiameter daemon */
+#define	EYEC_CONFIG	0xC011F16
+struct fd_config {
+	int		 cnf_eyec;	/* Eye catcher: EYEC_CONFIG */
+	
+	const char	*cnf_file;	/* Configuration file to parse, default is DEFAULT_CONF_FILE */
+	
+	DiamId_t  	 cnf_diamid;	/* Diameter Identity of the local peer (FQDN -- ASCII) */
+	size_t		 cnf_diamid_len;/* cached length of the previous string */
+	DiamId_t	 cnf_diamrlm;	/* Diameter realm of the local peer, default to realm part of cnf_diamid */
+	size_t		 cnf_diamrlm_len;/* length of the previous string */
+	
+	unsigned int	 cnf_timer_tc;	/* The value in seconds of the default Tc timer */
+	unsigned int 	 cnf_timer_tw;	/* The value in seconds of the default Tw timer */
+	
+	uint16_t	 cnf_port;	/* the local port for legacy Diameter (default: 3868) in host byte order */
+	uint16_t	 cnf_port_tls;	/* the local port for Diameter/TLS (default: 5868) in host byte order */
+	uint16_t	 cnf_port_3436; /* Open an additional server port to listen to old TLS/SCTP clients (RFC3436, freeDiameter versions < 1.2.0) */
+	uint16_t	 cnf_sctp_str;	/* default max number of streams for SCTP associations (def: 30) */
+	struct fd_list	 cnf_endpoints;	/* the local endpoints to bind the server to. list of struct fd_endpoint. default is empty (bind all). After servers are started, this is the actual list of endpoints including port information. */
+	int		 cnf_thr_srv;	/* Number of threads per servers handling the connection state machines */
+	struct fd_list	 cnf_apps;	/* Applications locally supported (except relay, see flags). Use fd_disp_app_support to add one. list of struct fd_app. */
+	uint16_t	 cnf_dispthr;	/* Number of dispatch threads to create */
+	struct {
+		unsigned no_fwd : 1;	/* the peer does not relay messages (0xffffff app id) */
+		unsigned no_ip4 : 1;	/* disable IP */
+		unsigned no_ip6 : 1;	/* disable IPv6 */
+		unsigned no_tcp : 1;	/* disable use of TCP */
+		unsigned no_sctp: 1;	/* disable the use of SCTP */
+		unsigned pr_tcp	: 1;	/* prefer TCP over SCTP */
+		unsigned tls_alg: 1;	/* TLS algorithm for initiated cnx. 0: separate port. 1: inband-security (old) */
+	} 		 cnf_flags;
+	
+	struct {
+		int				 tls_disabled;
+		
+		/* Credentials parameters (backup) */
+		char *  			 cert_file;
+		char *				 key_file;
+		
+		char *  			 ca_file;
+		int				 ca_file_nr;
+		char *  			 crl_file;
+		
+		char *				 prio_string;
+		unsigned int 			 dh_bits;
+		char *				 dh_file;
+		
+		/* GNUTLS parameters */
+		gnutls_priority_t 		 prio_cache;
+		gnutls_dh_params_t 		 dh_cache;
+		
+		/* GNUTLS server credential(s) */
+		gnutls_certificate_credentials_t credentials; /* contains local cert + trust anchors */
+		#ifdef GNUTLS_VERSION_300
+		gnutls_x509_trust_list_t         trustlist; /* the logic to check local certificate has changed */
+		#endif /* GNUTLS_VERSION_300 */
+		
+	} 		 cnf_sec_data;
+	
+	uint32_t	 cnf_orstateid;	/* The value to use in Origin-State-Id, default to random value */
+	struct dictionary *cnf_dict;	/* pointer to the global dictionary */
+	struct fifo	  *cnf_main_ev;	/* events for the daemon's main (struct fd_event items) */
+};
+extern struct fd_config *fd_g_config; /* The pointer to access the global configuration, initalized in main */
+
+
+
+/*============================================================*/
+/*                         PEERS                              */
+/*============================================================*/
+
+/* States of a peer */
+enum peer_state {
+	/* Stable states */
+	STATE_NEW = 0,		/* The peer has been just been created, PSM thread not started yet */
+	STATE_OPEN,		/* Connexion established */
+	
+	/* Peer state machine */
+	STATE_CLOSED,		/* No connection established, will re-attempt after TcTimer. */
+	STATE_CLOSING,		/* the connection is being shutdown (DPR/DPA in progress) */
+	STATE_WAITCNXACK,	/* Attempting to establish transport-level connection */
+	STATE_WAITCNXACK_ELEC,	/* Received a CER from this same peer on an incoming connection (other peer object), while we were waiting for cnx ack */
+	STATE_WAITCEA,		/* Connection established, CER sent, waiting for CEA */
+	/* STATE_WAITRETURNS_ELEC, */	/* This state is not stable and therefore deprecated:
+				   We have sent a CER on our initiated connection, and received a CER from the remote peer on another connection. Election.
+				   If we win the election, we must disconnect the initiated connection and send a CEA on the other => we go to OPEN state.
+				   If we lose, we disconnect the other connection (receiver) and fallback to WAITCEA state. */
+	STATE_OPEN_HANDSHAKE,	/* TLS Handshake and validation are in progress in open state -- we use it only for debug purpose, it is never displayed */
+	
+	/* Failover state machine */
+	STATE_SUSPECT,		/* A DWR was sent and not answered within TwTime. Failover in progress. */
+	STATE_REOPEN,		/* Connection has been re-established, waiting for 3 DWR/DWA exchanges before putting back to service */
+	
+	/* Ordering issues with multistream & state machine. -- see top of p_psm.c for explanation */
+	STATE_OPEN_NEW, 	/* after CEA is sent, until a new message is received. Force ordering in this state */
+	STATE_CLOSING_GRACE,	/* after DPA is sent or received, give a short delay for messages in the pipe to be received. */
+	
+	/* Error state */
+	STATE_ZOMBIE		/* The PSM thread is not running anymore; it must be re-started or peer should be deleted. */
+#define STATE_MAX STATE_ZOMBIE
+};
+/* The following macro is called in freeDiameter/p_psm.c */
+#define DECLARE_STATE_STR()		\
+const char *peer_state_str[] = { 	\
+	  "STATE_NEW"			\
+	, "STATE_OPEN"			\
+	, "STATE_CLOSED"		\
+	, "STATE_CLOSING"		\
+	, "STATE_WAITCNXACK"		\
+	, "STATE_WAITCNXACK_ELEC"	\
+	, "STATE_WAITCEA"		\
+	, "STATE_OPEN_HANDSHAKE"	\
+	, "STATE_SUSPECT"		\
+	, "STATE_REOPEN"		\
+	, "STATE_OPEN_NEW"		\
+	, "STATE_CLOSING_GRACE"		\
+	, "STATE_ZOMBIE"		\
+	};
+extern const char *peer_state_str[];
+#define STATE_STR(state) \
+	(((unsigned)(state)) <= STATE_MAX ? peer_state_str[((unsigned)(state)) ] : "<Invalid>")
+
+/* Constants for the peer_info structure below */
+#define PI_P3_DEFAULT	0	/* Use any available protocol */
+#define PI_P3_IP	1	/* Use only IP to connect to this peer */
+#define PI_P3_IPv6	2	/* resp, IPv6 */
+
+#define PI_P4_DEFAULT	0	/* Attempt any available protocol */
+#define PI_P4_TCP	1	/* Only use TCP */
+#define PI_P4_SCTP	2	/* Only use SCTP */
+
+#define PI_ALGPREF_SCTP	0	/* SCTP is  attempted first (default) */
+#define PI_ALGPREF_TCP	1	/* TCP is attempted first */
+
+#define PI_SEC_DEFAULT	0	/* New TLS security (handshake after connection, protecting also CER/CEA) */
+#define PI_SEC_NONE	1	/* Transparent security with this peer (IPsec) */
+#define PI_SEC_TLS_OLD	2	/* Old TLS security (use Inband-Security-Id AVP during CER/CEA) */
+				/* Set sec = 3 to authorize use of (Inband-Security-Id == NONE) with this peer, sec = 2 only authorizing TLS */
+				
+#define PI_SCTPSEC_DEF	0	/* Use DTLS over SCTP to connect to this peer (default) */
+#define PI_SCTPSEC_3436	1	/* Use TLS over SCTP to connect to this peer (RFC3436) */
+
+#define PI_EXP_NONE	0	/* the peer entry does not expire */
+#define PI_EXP_INACTIVE	1	/* the peer entry expires (i.e. is deleted) after pi_lft seconds without activity */
+
+#define PI_PRST_NONE	0	/* the peer entry is deleted after disconnection / error */
+#define PI_PRST_ALWAYS	1	/* the peer entry is persistant (will be kept as ZOMBIE in case of error) */
+			
+/* Information about a remote peer */
+struct peer_info {
+	
+	DiamId_t	pi_diamid;	/* (supposedly) UTF-8, \0 terminated. The Diameter Identity of the remote peer. */
+	size_t		pi_diamidlen;	/* cached length of pi_diamid */
+	
+	struct {
+		struct {
+			unsigned	pro3 :2;	/* PI_P3_* */
+			unsigned	pro4 :2;	/* PI_P4_* */
+			unsigned	alg :1;		/* PI_ALGPREF_* */
+			unsigned	sec :2;		/* PI_SEC_* */
+			unsigned	sctpsec :1;	/* PI_SCTPSEC_* */
+			unsigned	exp :1;		/* PI_EXP_* */
+			unsigned	persist :1;	/* PI_PRST_* */
+			
+		}		pic_flags;	/* Flags influencing the connection to the remote peer */
+		
+		DiamId_t	pic_realm;	/* If configured, the daemon will check the received realm in CER/CEA matches this. */
+		uint16_t	pic_port; 	/* port to connect to. 0: default. */
+		
+		uint32_t 	pic_lft;	/* lifetime of this peer when inactive (see pic_flags.exp definition) */
+		int		pic_tctimer; 	/* use this value for TcTimer instead of global, if != 0 */
+		int		pic_twtimer; 	/* use this value for TwTimer instead of global, if != 0 */
+		
+		char *		pic_priority;	/* Priority string for GnuTLS if we don't use the default */
+		
+	} config;	/* Configured data (static for this peer entry) */
+	
+	struct {
+		
+		/* enum peer_state	pir_state; */ 
+		/* Since 1.1.0, read the state with fd_peer_getstate(peer). */
+		
+		DiamId_t	pir_realm;	/* The received realm in CER/CEA. */
+		size_t		pir_realmlen;	/* length of the realm */
+		
+		uint32_t	pir_vendorid;	/* Content of the Vendor-Id AVP, or 0 by default */
+		uint32_t	pir_orstate;	/* Origin-State-Id value */
+		os0_t		pir_prodname;	/* copy of Product-Name AVP (\0 terminated) */
+		uint32_t	pir_firmrev;	/* Content of the Firmware-Revision AVP */
+		int		pir_relay;	/* The remote peer advertized the relay application */
+		struct fd_list	pir_apps;	/* applications advertised by the remote peer, except relay (pi_flags.relay) */
+		int		pir_isi;	/* Inband-Security-Id advertised (PI_SEC_* bits) */
+		
+		uint32_t	pir_lastDC;	/* The last Disconnect-Cause value received */
+		
+		int		pir_proto;	/* The L4 protocol currently used with the peer (IPPROTO_TCP or IPPROTO_SCTP) */
+		const gnutls_datum_t 	*pir_cert_list; 	/* The (valid) credentials that the peer has presented, or NULL if TLS is not used */
+								/* This is inspired from http://www.gnu.org/software/gnutls/manual/gnutls.html#ex_003ax509_002dinfo 
+								   see there for example of using this data */
+		unsigned int 	pir_cert_list_size;		/* Number of certificates in the list */
+		
+	} runtime;	/* Data populated after connection, may change between 2 connections -- not used by fd_peer_add */
+	
+	struct fd_list	pi_endpoints;	/* Endpoint(s) of the remote peer (configured, discovered, or advertized). list of struct fd_endpoint. DNS resolved if empty. */
+};
+
+
+struct peer_hdr {
+	struct fd_list	 chain;	/* Link into the list of all the peers, ordered by their Diameter Id (fd_os_cmp) */
+	struct peer_info info;	/* The public data */
+	
+	/* This header is followed by more data in the private peer structure definition */
+};
+
+/* the global list of peers. 
+  Since we are not expecting so many connections, we don't use a hash, but it might be changed.
+  The list items are peer_hdr structures (actually, fd_peer, but the cast is OK) */
+extern struct fd_list fd_g_peers;
+extern pthread_rwlock_t fd_g_peers_rw; /* protect the list */
+
+/*
+ * FUNCTION:	fd_peer_add
+ *
+ * PARAMETERS:
+ *  info 	: Information to create the peer.
+ *  orig_dbg	: A string indicating the origin of the peer information, for debug (ex: conf, redirect, ...)
+ *  cb		: optional, a callback to call (once) when the peer connection is established or failed
+ *  cb_data	: opaque data to pass to the callback.
+ *
+ * DESCRIPTION: 
+ *  Add a peer to the list of peers to which the daemon must maintain a connexion.
+ *
+ *  The content of info parameter is copied, except for the list of endpoints if 
+ * not empty, which is simply moved into the created object. It means that the list
+ * items must have been malloc'd, so that they can be freed.
+ *
+ *  If cb is not null, the callback is called when the connection is in OPEN state or
+ * when an error has occurred. The callback should use the pi_state information to 
+ * determine which one it is. If the first parameter of the called callback is NULL, it 
+ * means that the peer is being destroyed before attempt success / failure. 
+ * cb is called to allow freeing cb_data in  * this case.
+ *
+ *  The orig_dbg string is only useful for easing debug, and can be left to NULL.
+ *
+ * RETURN VALUE:
+ *  0      	: The peer is added.
+ *  EINVAL 	: A parameter is invalid.
+ *  EEXIST 	: A peer with the same Diameter-Id is already in the list.
+ *  (other standard errors may be returned, too, with their standard meaning. Example:
+ *    ENOMEM 	: Memory allocation for the new object element failed.)
+ */
+int fd_peer_add ( struct peer_info * info, const char * orig_dbg, void (*cb)(struct peer_info *, void *), void * cb_data );
+
+/*
+ * FUNCTION:	fd_peer_getbyid
+ *
+ * PARAMETERS:
+ *  diamid 	: an UTF8 string describing the diameter Id of the peer to seek
+ *  diamidlen	: length of the diamid
+ *  igncase	: perform an almost-case-insensitive search? (slower)
+ *  peer	: The peer is stored here if it exists.
+ *
+ * DESCRIPTION: 
+ *   Search a peer by its Diameter-Id.
+ *
+ * RETURN VALUE:
+ *  0   : *peer has been updated (to NULL if the peer is not found).
+ * !0	: An error occurred.
+ */
+int fd_peer_getbyid( DiamId_t diamid, size_t diamidlen, int igncase, struct peer_hdr ** peer );
+
+/* 
+ * FUNCTION:	fd_peer_get_state
+ *
+ * PARAMETERS:
+ *  peer	: The peer which state to read
+ *
+ * DESCRIPTION: 
+ *   Returns the current state of the peer.
+ *
+ * RETURN VALUE:
+ *  -1  : peer is invalid
+ * >=0	: the state of the peer at the time of reading.
+ */
+int fd_peer_get_state(struct peer_hdr *peer);
+
+/* 
+ * FUNCTION:	fd_peer_cnx_proto_info
+ *
+ * PARAMETERS:
+ *  peer	: The peer which information to be read
+ *  buf		: Where to store the protocol information
+ *  len		: available space in bug
+ *
+ * DESCRIPTION: 
+ *   Creates a string describing the current connection to this peer, e.g.: "TCP,TLS,soc#3".
+ *
+ * RETURN VALUE:
+ *  0   : buffer was written
+ * >=0	: error code.
+ */
+int fd_peer_cnx_proto_info(struct peer_hdr *peer, char * buf, size_t len);
+
+/* 
+ * FUNCTION:	fd_peer_get_load_pending
+ *
+ * PARAMETERS:
+ *  peer	: The peer which load to read
+ *  to_receive  : (out) number of requests sent to this peer without matching answer yet.
+ *  to_send     : (out) number of requests received from this peer and not yet answered.
+ *
+ * DESCRIPTION: 
+ *   Returns the current number of requests sent to this peer
+ *  that have not been answered yet. This is an empirical indication
+ *  of the workload of this peer.
+ *
+ * RETURN VALUE:
+ *  0  : The load parameter has been updated. (it should have a positive value always)
+ * !0  : An error occurred
+ */
+int fd_peer_get_load_pending(struct peer_hdr *peer, long * to_receive, long * to_send);
+
+/*
+ * FUNCTION:	fd_peer_validate_register
+ *
+ * PARAMETERS:
+ *  peer_validate 	: Callback as defined below.
+ *
+ * DESCRIPTION: 
+ *  Add a callback to authorize / reject incoming peer connections.
+ * All registered callbacks are called until a callback sets auth = -1 or auth = 1.
+ * If no callback returns a clear decision, the default behavior is applied (reject unknown connections)
+ * The callbacks are called in FILO order of their registration.
+ *
+ * RETURN VALUE:
+ *  0   : The callback is added.
+ * !0	: An error occurred.
+ */
+int fd_peer_validate_register ( int (*peer_validate)(struct peer_info * /* info */, int * /* auth */, int (**cb2)(struct peer_info *)) );
+/*
+ * CALLBACK:	peer_validate
+ *
+ * PARAMETERS:
+ *   info     : Structure containing information about the peer attempting the connection.
+ *   auth     : Store there the result if the peer is accepted (1), rejected (-1), or unknown (0).
+ *   cb2      : If != NULL and in case of PI_SEC_TLS_OLD, another callback to call after handshake (if auth = 1).
+ *
+ * DESCRIPTION: 
+ *   This callback is called when a new connection is being established from an unknown peer,
+ * after the CER is received. An extension must register such callback with peer_validate_register.
+ *
+ *   The callback can learn if the peer has sent Inband-Security-Id AVPs in runtime.pir_isi fields.
+ * It can also learn if a handshake has already been performed in runtime.pir_cert_list field.
+ * The callback must set the value of config.pic_flags.sec appropriately to allow a connection without TLS.
+ *
+ *   If the old TLS mechanism is used,
+ * the extension may also need to check the credentials provided during the TLS
+ * exchange (remote certificate). For this purpose, it may set the address of a new callback
+ * to be called once the handshake is completed. This new callback receives the information
+ * structure as parameter (with pir_cert_list set) and returns 0 if the credentials are correct,
+ * or an error code otherwise. If the error code is received, the connection is closed and the 
+ * peer is destroyed.
+ * Note that freeDiameter already achieves some usual checks. The callback may be used to enforce
+ * additional restrictions.
+ *
+ * RETURN VALUE:
+ *  0      	: The authorization decision has been written in the location pointed by auth.
+ *  !0 		: An error occurred.
+ */
+
+
+
+/*============================================================*/
+/*                         MESSAGES                           */
+/*============================================================*/
+
+/*
+ * FUNCTION:	fd_msg_send, fd_msg_send_timeout  
+ *
+ * PARAMETERS:
+ *  pmsg 	: Location of the message to be sent on the network (set to NULL on function return to avoid double deletion).
+ *  anscb	: A callback to be called when corresponding answer is received, when sending a request (not used with answers)
+ *  anscb_data	: opaque data to be passed back to the anscb (or expirecb) when it is called.
+ *  expirecb    : (only for fd_msg_send_timeout) If the request did not get an answer before timeout, this callback is called.
+ *  timeout     : (only for fd_msg_send_timeout) sets the absolute time until when to wait for an answer. Past this time,
+ *                the expirecb is called with the request and the answer will be discarded if received later.
+ *
+ * DESCRIPTION: 
+ *   Sends a message on the network. (actually simply queues it in a global queue, to be picked by a daemon's thread)
+ * For requests, the end-to-end id must be set (see fd_msg_get_eteid / MSGFL_ALLOC_ETEID).
+ * For answers, the message must be created with function fd_msg_new_answer_from_req.
+ *
+ * The routing module will handle sending to the correct peer, usually based on the Destination-Realm / Destination-Host AVP.
+ *
+ * If the msg is a request, there are two ways of receiving the answer:
+ *  - either having registered a callback in the dispatch module (see fd_disp_register)
+ *  - or provide a anscb callback here. If such callback is provided, it is called before the dispatch callbacks.
+ *    The prototype for this anscb callback function is:
+ *     void anscb(void * data, struct msg ** answer)
+ *	where:
+ *		data   : opaque data that was registered along with the callback.
+ *		answer : location of the pointer to the answer.
+ *      note1: on function return, if *answer is not NULL, the message is passed to the dispatch module for regular callbacks.
+ *	       otherwise, the callback must take care of freeing the message (fd_msg_free).
+ *	note2: the opaque data is not freed by the daemon in any case, extensions should ensure clean handling in fd_ext_fini.
+ * 
+ * If no callback is registered to handle an answer, the message is discarded and an error is logged.
+ *
+ *  fd_msg_send_timeout is similar to fd_msg_send, except that it takes two additional arguments "expirecb" and "timeout". 
+ * If the message parameter is an answer, there is no difference with fd_msg_send.
+ * Otherwise, if the corresponding answer (or error) is received before the timeout date elapses, everything occurs as with fd_msg_send. 
+ * Otherwise, the request is removed from the queue (meaning the matching answer will be discarded upon reception) and passed to the expirecb 
+ * function. Upon return, if the *msg parameter is not NULL, it is freed (not passed to other callbacks). 
+ * expirecb is called in a dedicated thread.
+ * 
+ *    The prototype for the expirecb callback function is:
+ *     void expirecb(void * data, struct peer_hdr * sentto, struct msg ** request)
+ *	where:
+ *		data   : opaque data that was registered along with the callback.
+ *              sentto : pointer to the peer to which the message was sent and no answer received within timeout.
+ *		request: location of the pointer to the request that was not answered.
+ *
+ * RETURN VALUE:
+ *  0      	: The message has been queued for sending (sending may fail asynchronously).
+ *  EINVAL 	: A parameter is invalid (ex: anscb provided but message is not a request).
+ *  ...
+ */
+int fd_msg_send ( struct msg ** pmsg, void (*anscb)(void *, struct msg **), void * data );
+int fd_msg_send_timeout ( struct msg ** pmsg, void (*anscb)(void *, struct msg **), void * data, void (*expirecb)(void *, DiamId_t, size_t, struct msg **), const struct timespec *timeout );
+
+/*
+ * FUNCTION:	fd_msg_rescode_set
+ *
+ * PARAMETERS:
+ *  msg		: A msg object -- it must be an answer.
+ *  rescode	: The name of the returned error code (ex: "DIAMETER_INVALID_AVP")
+ *  errormsg    : (optional) human-readable error message to put in Error-Message AVP
+ *  optavp	: (optional) If provided, the content will be put inside a Failed-AVP
+ *  type_id	: 0 => nothing; 1 => adds Origin-Host and Origin-Realm with local info. 2=> adds Error-Reporting-Host.
+ *
+ * DESCRIPTION: 
+ *   This function adds a Result-Code AVP to a message, and optionally
+ *  - sets the 'E' error flag in the header,
+ *  - adds Error-Message, Error-Reporting-Host and Failed-AVP AVPs.
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0      	: an error occurred.
+ */
+int fd_msg_rescode_set( struct msg * msg, char * rescode, char * errormsg, struct avp * optavp, int type_id );
+
+/* Add Origin-Host, Origin-Realm, (if osi) Origin-State-Id AVPS at the end of the message */
+int fd_msg_add_origin ( struct msg * msg, int osi ); 
+
+/* Generate a new Session-Id and add it at the beginning of the message (opt is added at the end of the sid if provided) */
+int fd_msg_new_session( struct msg * msg, os0_t opt, size_t optlen );
+
+
+/* Parse a message against our dictionary, 
+	return 0 in case of success.
+	log parsing error & return error code in case of failure in parsing. 
+	In addition, if the error code is EBADMSG (the message does not follow our dictionary) 
+		if *msg was a request, *msg is NULL and *error contains the error message ready to send back on return
+		if *msg was an answer, *msg is untouched and *error==*msg if *msg was an error message, *error is null otherwise */
+int fd_msg_parse_or_error( struct msg ** msg, struct msg **error );
+
+
+
+
+/*============================================================*/
+/*                         DISPATCH                           */
+/*============================================================*/
+
+/*
+ * FUNCTION:	fd_disp_app_support
+ *
+ * PARAMETERS:
+ *  app		: The dictionary object corresponding to the Application.
+ *  vendor	: (Optional) the dictionary object of a Vendor to claim support in Vendor-Specific-Application-Id
+ *  auth	: Support auth app part.
+ *  acct	: Support acct app part.
+ *
+ * DESCRIPTION: 
+ *   Registers an application to be advertized in CER/CEA exchanges.
+ *  Messages with an application-id matching a registered value are passed to the dispatch module,
+ * while other messages are simply relayed or an error is returned (if local node does not relay)
+ *
+ * RETURN VALUE:
+ *  0      	: The application support is registered.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_disp_app_support ( struct dict_object * app, struct dict_object * vendor, int auth, int acct );
+
+/* Note: if we want to support capabilities updates, we'll have to add possibility to remove an app as well... */
+
+
+/*============================================================*/
+/*                         ROUTING                            */
+/*============================================================*/
+
+/* This file contains the definitions of types and functions involved in the routing decisions in freeDiameter,
+ * and that can be called by extensions. 
+ *
+ * Three different type of messages must be distinguished:
+ *  - Messages received, and the peer is final recipient (IN messages)
+ *  - Messages received, and the peer is not final recipient (FWD messages)
+ *  - Message is locally generated (OUT messages)
+ *
+ * There are three global message queues (in queues.c) and also peers-specific queues (in struct fd_peer).
+ *
+ * (*) IN messages processing details:
+ *   - the message is received from the remote peer, a FDEVP_CNX_MSG_RECV event is generated for the peer.
+ *   - the PSM thread parses the buffer, does some verifications, handles non routable messages (fd_msg_is_routable)
+ *   - routable messages are queued in the fd_g_incoming global queue.
+ *   - a thread (routing-in) picks the message and takes the decision if it is handled locally or forwarded, 
+ *       based on local capabilities (registered by extensions with fd_disp_app_support).
+ *   - If the message is handled locally, it is queued in fd_g_local.
+ *   - Another thread (dispatch.c) will handle this message and pass it to registered callbacks (see fd_disp_register in libfreeDiameter.h).
+ *
+ * (*) FWD messages details:
+ *   - The process is the same as for IN messages, until the routing-in threads makes its decision that the message is not handled locally.
+ *   - If the local peer does not relay message, an error DIAMETER_APPLICATION_UNSUPPORTED is returned.
+ *   - All callbacks registered with fd_rt_fwd_register are called for the message (see below).
+ *     - these callbacks will typically do proxying work. Note that adding the route-record is handled by the daemon.
+ *   - Once all callbacks have been called, the message is queued in the global fd_g_outgoing queue.
+ *   - The remaining processing is the same as for OUT messages, as described below.
+ *
+ * (*) OUT messages details:
+ *   - The message are picked from fd_g_outgoing (they are queued there as result of forwarding process or call to fd_msg_send.)
+ *   - The (routing-out) thread builds a list of possible destinations for the message, as follow:
+ *      - create a list of all known peers in the "OPEN" state.
+ *      - remove from that list all peers that are in a Route-Record AVP of the message, to avoid routing loops.
+ *      - remove also all peers that have previously replied an error message for this message.
+ *   - If the list is empty, create an error UNABLE_TO_DELIVER (note: should we trig dynamic discovery here???) and reply.
+ *   - Otherwise, call all callbacks registered by function fd_rt_out_register, with the list of peers and the message.
+ *   - Order the resulting list of peers by score (see below), and sent the message to the peer with highest (positive) score.
+ *    - in case the peer is no longer in the "OPEN" state, send the message to the second peer in the list.
+ *      - if no peer is in OPEN state anymore, restart the process of creating the list.
+ *   - Once a peer has been selected, the message is queued into that peer's outgoing queue.
+ *
+ * The following functions allow an extension to register or remove a callback as described above.
+ */
+
+/********** Forwarding callbacks: for Proxy operations ***********/
+
+/* Handle to registered callback */
+struct fd_rt_fwd_hdl;
+
+/* Message direction for the callback */
+enum fd_rt_fwd_dir {
+	RT_FWD_REQ = 1,	/* The callback will be called on forwarded requests only */
+	RT_FWD_ALL = 2,	/* The callback will be called on all forwarded messages (requests and answers )*/
+	RT_FWD_ANS = 3	/* The callback will be called on answers and errors only */
+};	
+
+/*
+ * FUNCTION:	fd_rt_fwd_register
+ *
+ * PARAMETERS:
+ *  rt_fwd_cb	  : The callback function to register (see prototype below).
+ *  cbdata	  : Pointer to pass to the callback when it is called. The data is opaque to the daemon.
+ *  dir           : One of the RT_FWD_* directions defined above.
+ *  handler       : On success, a handler to the registered callback is stored here. 
+ *		   This handler will be used to unregister the cb.
+ *
+ * DESCRIPTION: 
+ *   Register a new callback for forwarded messages. See explanations above. 
+ * Note that there is no guaranteed order for the callbacks calls.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is registered.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_rt_fwd_register ( int (*rt_fwd_cb)(void * cbdata, struct msg ** msg), void * cbdata, enum fd_rt_fwd_dir dir, struct fd_rt_fwd_hdl ** handler );
+/*
+ * CALLBACK:	rt_fwd_cb
+ *
+ * PARAMETERS:
+ *  data	: pointer to some data that was passed when the callback was registered (optional).
+ *  msg 	: The message that is being forwarded.
+ *
+ * DESCRIPTION: 
+ *   This callback is called when a message is forwarded to another peer. It may for example add a Proxy-Info AVP.
+ *  The callback may also choose to handle the message in a more complex form. In that case, it must set *msg = NULL
+ *  and handle it differently. In such case, the forwarding thread will stop processing this message.
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0 		: An error occurred -- will result in daemon's termination.
+ */
+
+/*
+ * FUNCTION:	fd_rt_fwd_unregister
+ *
+ * PARAMETERS:
+ *  handler     : The handler of the callback that must be unregistered.
+ *  cbdata	: Will receive the data registered with the callback, that can be freed if needed.
+ *
+ * DESCRIPTION: 
+ *   Removes a callback from the list of registered callbacks.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is unregistered.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_rt_fwd_unregister ( struct fd_rt_fwd_hdl * handler, void ** cbdata );
+
+
+/********** Out callbacks: for next hop routing decision operations ***********/
+
+/* Handle to registered callback */
+struct fd_rt_out_hdl;
+
+enum fd_rt_out_score {
+	FD_SCORE_NO_DELIVERY	 = -70,	/* We should not send this message to this candidate */
+	FD_SCORE_SENT_REDIRECT	 = -60, /* If this peer previously sent a Redirect indication that applies to this message */
+	FD_SCORE_INI		 =  -2, /* All candidates are initialized with this value */
+	FD_SCORE_LOAD_BALANCE	 =   1,	/* Use this to differentiate between several peers with the same score */
+	FD_SCORE_DEFAULT	 =   5,	/* The peer is a default route for all messages */
+	FD_SCORE_DEFAULT_REALM	 =  10,	/* The peer is a default route for this realm */
+	FD_SCORE_REALM		 =  15,	/* The peer belongs to Destination-Realm of the message */
+	FD_SCORE_REDIR_HOST	 =  25,	/* If there is a redirect rule with ALL_HOST for these message and peer */
+	FD_SCORE_REDIR_APP	 =  30,	/* If there is a redirect rule with ALL_APPLICATION for these message and peer */
+	FD_SCORE_REDIR_REALM	 =  35,	/* If there is a redirect rule with ALL_REALM for these message and peer */
+	FD_SCORE_REDIR_REALM_APP =  40,	/* If there is a redirect rule with REALM_AND_APPLICATION for these message and peer */
+	FD_SCORE_REDIR_USER	 =  45,	/* If there is a redirect rule with ALL_USER for these message and peer */
+	FD_SCORE_REDIR_SESSION	 =  50,	/* If there is a redirect rule with ALL_SESSION for these message and peer */
+	FD_SCORE_REDIR_ONCE	 =  55,	/* If there is a redirect rule with DONT_CACHE for these message and peer */
+	FD_SCORE_FINALDEST	 = 100	/* If the peer is the final recipient of the message (i.e. matching Destination-Host), it receives a big score. */
+};
+
+/*
+ * FUNCTION:	fd_rt_out_register
+ *
+ * PARAMETERS:
+ *  rt_out_cb	  : The callback function to register (see prototype below).
+ *  cbdata	  : Pointer to pass to the callback when it is called. The data is opaque to the daemon.
+ *  priority      : Order for calling this callback. The callbacks are called in reverse priority order (higher priority = called sooner).
+ *  handler       : On success, a handler to the registered callback is stored here. 
+ *		   This handler will be used to unregister the cb.
+ *
+ * DESCRIPTION: 
+ *   Register a new callback to handle OUT routing decisions. See explanations above. 
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is registered.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_rt_out_register ( int (*rt_out_cb)(void * cbdata, struct msg ** pmsg, struct fd_list * candidates), void * cbdata, int priority, struct fd_rt_out_hdl ** handler );
+/*
+ * CALLBACK:	rt_out_cb
+ *
+ * PARAMETERS:
+ *  cbdata	: pointer to some data that was registered with the callback.
+ *  pmsg 	: pointer to the message that must be sent. upon return if *msg is NULL, the processing stops and the message is not sent.
+ *  list        : The list of peers to which the message may be sent to, as returned by fd_rtd_candidate_extract
+ *
+ * DESCRIPTION: 
+ *   This callback must attribute a score (preferably from FD_SCORE_*) to each candidate peer in the list.
+ *  Once all registered callbacks have been called, the message is sent to the candidate with the highest score.
+ *  Note that each callback must *add* its locally-attributed score to the candidate current "score" parameter, not replace it!
+ *  Note also that this callback must be re-entrant since it may be called by several threads at the same time 
+ *  (for different messages)
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0 		: An error occurred.
+ */
+
+/*
+ * FUNCTION:	fd_rt_out_unregister
+ *
+ * PARAMETERS:
+ *  handler     : The handler of the callback that must be unregistered.
+ *  cbdata	: Will receive the data registered with the callback, that can be freed if needed.
+ *
+ * DESCRIPTION: 
+ *   Removes a callback from the list of registered callbacks.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is unregistered.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_rt_out_unregister ( struct fd_rt_out_hdl * handler, void ** cbdata );
+
+
+/*============================================================*/
+/*                         EVENTS                             */
+/*============================================================*/
+
+struct fd_event {
+	int	 code; /* codespace depends on the queue */
+	size_t 	 size;
+	void    *data;
+};
+
+/* Daemon's codespace: 1000->1999 (1500->1999 defined in fdcore-internal.h) */
+enum {
+	 FDEV_TERMINATE_INT= 1000	/* request to terminate. DO NOT USE. Use fd_core_shutdown() instead.  */
+	,FDEV_TRIGGER			/* Trigger available for extensions. size is sizeof(int), data is int * */
+};
+
+int fd_event_send(struct fifo *queue, int code, size_t datasz, void * data);
+int fd_event_get(struct fifo *queue, int * code, size_t * datasz, void ** data);
+int fd_event_timedget(struct fifo *queue, struct timespec * timeout, int timeoutcode, int * code, size_t * datasz, void ** data);
+void fd_event_destroy(struct fifo **queue, void (*free_cb)(void * data));
+const char * fd_ev_str(int event);
+
+/* for extensions */
+int fd_event_trig_regcb(int trigger_val, const char * module, void (*cb)(void));
+
+#ifndef SWIG
+DECLARE_FD_DUMP_PROTOTYPE(fd_event_trig_dump);
+
+/* The "old" FD_EV_DUMP_* events are replaced with direct calls to the following dump functions */
+DECLARE_FD_DUMP_PROTOTYPE(fd_conf_dump);
+
+DECLARE_FD_DUMP_PROTOTYPE(fd_ext_dump);
+#else /* SWIG */
+DECLARE_FD_DUMP_PROTOTYPE_simple(fd_event_trig_dump);
+DECLARE_FD_DUMP_PROTOTYPE_simple(fd_conf_dump);
+DECLARE_FD_DUMP_PROTOTYPE_simple(fd_ext_dump);
+#endif /* SWIG */
+DECLARE_FD_DUMP_PROTOTYPE(fd_servers_dump, int details);
+DECLARE_FD_DUMP_PROTOTYPE(fd_peer_dump_list, int details);
+DECLARE_FD_DUMP_PROTOTYPE(fd_peer_dump, struct peer_hdr * p, int details);
+
+/*============================================================*/
+/*                         ENDPOINTS                          */
+/*============================================================*/
+
+struct fd_endpoint {
+	struct fd_list  chain;	/* link in cnf_endpoints list */
+	
+	union {
+		sSS		ss;	/* the socket information. List is always ordered by ss value (memcmp) -- see fd_ep_add_merge */
+		sSA4		sin;
+		sSA6		sin6;
+		sSA		sa;
+	}
+#ifdef SWIG /* nested anonymous unions are not supported yet */
+			s
+#endif /* SWIG */
+	;
+	
+#define	EP_FL_CONF	(1 << 0)	/* This endpoint is statically configured in a configuration file */
+#define	EP_FL_DISC	(1 << 1)	/* This endpoint was resolved from the Diameter Identity or other DNS query */
+#define	EP_FL_ADV	(1 << 2)	/* This endpoint was advertized in Diameter CER/CEA exchange */
+#define	EP_FL_LL	(1 << 3)	/* Lower layer mechanism provided this endpoint */
+#define	EP_FL_PRIMARY	(1 << 4)	/* This endpoint is primary in a multihomed SCTP association */
+#define	EP_ACCEPTALL	(1 << 15)	/* This flag allows bypassing the address filter in fd_ep_add_merge. */
+	uint32_t	flags;		/* Additional information about the endpoint */
+		
+	/* To add: a validity timestamp for DNS records ? How do we retrieve this lifetime from DNS ? */
+};
+
+int fd_ep_add_merge( struct fd_list * list, sSA * sa, socklen_t sl, uint32_t flags );
+int fd_ep_filter( struct fd_list * list, uint32_t flags );
+int fd_ep_filter_family( struct fd_list * list, int af );
+int fd_ep_clearflags( struct fd_list * list, uint32_t flags );
+DECLARE_FD_DUMP_PROTOTYPE(fd_ep_dump_one, int preamble, struct fd_endpoint * ep );
+DECLARE_FD_DUMP_PROTOTYPE(fd_ep_dump, int preamble, int indent, struct fd_list * eps  );
+
+
+/*============================================================*/
+/*                         APPLICATIONS IDs                   */
+/*============================================================*/
+
+struct fd_app {
+	struct fd_list	 chain;	/* link in cnf_apps list. List ordered by appid. */
+	struct {
+		unsigned auth   : 1;
+		unsigned acct   : 1;
+	}		 flags;
+	vendor_id_t	 vndid; /* if not 0, Vendor-Specific-App-Id AVP will be used */
+	application_id_t appid;	/* The identifier of the application */
+};
+	
+int fd_app_merge(struct fd_list * list, application_id_t aid, vendor_id_t vid, int auth, int acct);
+int fd_app_check(struct fd_list * list, application_id_t aid, struct fd_app **detail);
+int fd_app_check_common(struct fd_list * list1, struct fd_list * list2, int * common_found);
+int fd_app_empty(struct fd_list * list);
+
+
+
+/*============================================================*/
+/*                         MONITORING                         */
+/*============================================================*/
+
+/* These functions allow an extension to collect state information about the
+ * framework, as well as being hooked at some key checkpoints in the processing
+ * for logging or statistics purpose.
+ */
+ 
+
+/* CALLBACK: 	fd_hook_cb
+ *
+ * PARAMETERS:
+ *  type	: The type of hook that triggered this call, in case same cb is registered for several hooks.
+ *  msg 	: If relevant, the pointer to the message triggering the call. NULL otherwise.
+ *  peer        : If relevant, the pointer to the peer associated with the call. NULL otherwise.
+ *  other	: For some callbacks, the remaining information is passed in this parameter. See each hook detail.
+ *  permsgdata  : Structure associated with a given message, across several hooks. 
+ *                 A different structure is associated with requests and corresponding answers. 
+ *                 See fd_hook_data_hdl below for details.
+ *                 If no fd_hook_data_hdl is registered with this callback, this parameter is always NULL
+ *  regdata     : Data pointer stored at registration, opaque for the framework.
+ *
+ * DESCRIPTION: 
+ *   When such callback is registered with fd_hook_register function, it will be called on matching events with 
+ * the parameters as described in the list of fd_hook_type below. One can use this mechanism for e.g.:
+ *  - log completely the messages for safety / backup
+ *  - create statistics information on the throughput
+ *  - ...
+ *
+ *  IMPORTANT: the callback MUST NOT change the memory pointed by the different parameters (peer, message, ...)
+ *
+ * RETURN VALUE:
+ *  none.
+ */
+ 
+/* The available hooks in the framework */
+enum fd_hook_type {
+
+	HOOK_DATA_RECEIVED = 0,
+		/* Hook called as soon as a message has been received from the network, after TLS & boundary processing.
+		 - {msg} is NULL.
+		 - {peer} is NULL.
+		 - {other} is a pointer to a struct fd_cnx_rcvdata containing the received buffer.
+		 - {permsgdata} points to either a new empty structure allocated for this message (cf. fd_hook_data_hdl), or NULL if no hdl is registered.
+		 */
+		 
+	HOOK_MESSAGE_RECEIVED,
+		/* Hook called when a message has been received and the structure has been parsed successfully (list of AVPs).
+		 - {msg} points to the parsed message. At this time, the objects have not been dictionary resolved. If you
+		   try to call fd_msg_parse_dict, it will slow down the operation of a relay agent.
+		 - {peer} is set if the message is received from a peer's connection, and NULL if the message is from a new client
+		   connected and not yet identified
+		 - {other} is NULL, or a char * identifying the connection when {peer} is null.
+		 - {permsgdata} points to either a new empty structure allocated for this message or the one passed to HOOK_DATA_RECEIVED if used.
+		 */
+	
+	HOOK_MESSAGE_LOCAL,
+		/* Hook called when a request message has been created locally by an extension and is being sent.
+		 - {msg} points to the message.
+		 - {peer} is NULL
+		 - {other} is NULL
+		 - {permsgdata} points to a new empty structure allocated for this request (cf. fd_hook_data_hdl)
+		 */
+	
+	HOOK_MESSAGE_SENDING,
+		/* Hook called when a message is about to be sent to a peer. The message pointer cannot be modified here, but the content of the message
+		  could still be changed (for example add or remove some AVP. This is the last chance.
+		 - {msg} points to the message. Some objects may not have been dictionary resolved. If you
+		   try to call fd_msg_parse_dict, it will slow down the operation of the instance.
+		 - {peer} is the one the message is being sent to.
+		 - {other} is NULL.
+		 - {permsgdata} points to existing structure if any, or a new structure otherwise. 
+		 */
+	
+	HOOK_MESSAGE_SENT,
+		/* Hook called when a message has been sent to a peer. The message might be freed as soon as the hook function returns,
+		   so it is not safe to store the pointer for asynchronous processing.
+		 - {msg} points to the sent message. Again, the objects may not have been dictionary resolved. If you
+		   try to call fd_msg_parse_dict, it will slow down the operation of a relay agent.
+		 - {peer} is set if the message is sent to a peer's connection, and NULL if the message is sent to a new client
+		   connected and not yet identified, or being rejected
+		 - {other} is NULL.
+		 - {permsgdata} points to existing structure if any, or a new structure otherwise. 
+		 */
+	
+	HOOK_MESSAGE_FAILOVER,
+		/* Hook called when a message that was sent to a peer is being requeued, because e.g. the connection was torn down.
+		   In that case the message will go again through the routing process.
+		 - {msg} points to the corresponding request message (the answer is discarded). Again, the objects may not have been dictionary resolved. If you
+		   try to call fd_msg_parse_dict, it might slow down the operation of a relay agent, although this hook is not on the normal execution path.
+		 - {peer} is the peer this message was previously sent to.
+		 - {other} is NULL.
+		 - {permsgdata} points to existing structure if any, or a new structure otherwise. 
+		 */
+	
+	HOOK_MESSAGE_PARSING_ERROR,
+		/* Hook called when a message being processed cannot be parsed successfully.
+		 - {msg} points to the message if buffer was parsed successfully, or NULL otherwise. You should not call fd_msg_parse_dict on this in any case.
+		 - {peer} is NULL or the peer that received the message. If NULL and the message is not NULL, you can still retrieve the source from the message itself.
+		 - {other} is a char * pointer to the error message (human-readable) if {msg} is not NULL, a pointer to struct fd_cnx_rcvdata containing the received buffer otherwise.
+		 - {permsgdata} points to existing structure associated with this message (or new structure if no previous hook was registered). 
+		 */
+		 
+	HOOK_MESSAGE_ROUTING_ERROR,
+		/* Hook called when a message being processed by the routing thread meets an error such as no remaining available peer for sending, based on routing callbacks decisions (maybe after retries).
+		 - {msg} points to the message. Again, the objects may not have been dictionary resolved. If you
+		   try to call fd_msg_parse_dict, it might slow down the operation of a relay agent, although this hook is not on the normal execution path.
+		 - {peer} is NULL.
+		 - {other} is a char * pointer to the error message (human-readable).
+		 - {permsgdata} points to existing structure associated with this message (or new structure if no previous hook was registered). 
+		 */
+	
+	HOOK_MESSAGE_ROUTING_FORWARD,
+		/* Hook called when a received message is deemed to be not handled locally by the routing_dispatch process.
+		   The decision of knowing which peer it will be sent to is not made yet (or if an error will be returned).
+		   The hook is trigged before the callbacks registered with fd_rt_fwd_register are called.
+		 - {msg} points to the message. Again, the objects may not have been dictionary resolved. 
+		    If you try to call fd_msg_parse_dict, it will slow down the operation of a relay agent.
+		 - {peer} is NULL.
+		 - {other} is NULL.
+		 - {permsgdata} points to existing structure associated with this message (or new structure if no previous hook was registered). 
+		 */
+	
+	HOOK_MESSAGE_ROUTING_LOCAL,
+		/* Hook called when a received message is handled locally by the routing_dispatch process (i.e., not forwarded).
+		   The hook is trigged before the callbacks registered with fd_disp_register are called.
+		 - {msg} points to the message. Here, the message has been already parsed completely & successfully.
+		 - {peer} is NULL.
+		 - {other} is NULL.
+		 - {permsgdata} points to existing structure associated with this message (or new structure if no previous hook was registered). 
+		 */
+	
+	HOOK_MESSAGE_DROPPED,
+		/* Hook called when a message is being discarded by the framework because of some error condition (normal or abnormal).
+		   It is probably a good idea to log this for analysis / backup.
+		 - {msg} points to the message, which will be freed as soon as the hook returns.
+		 - {peer} may be NULL or a peer related to the event.
+		 - {other} is a char * pointer to the error message (human-readable).
+		 - {permsgdata} points to existing structure associated with this message (or new structure if no previous hook was registered).
+		 */
+	
+	HOOK_PEER_CONNECT_FAILED,
+		/* Hook called when a connection attempt to/from a remote peer has failed. This hook is also called when the peer was in OPEN state and the connection is broken.
+		 - {msg} may be NULL (lower layer error, e.g. connection timeout) or points to a message showing the error (either invalid incoming message, or the CEA message sent or received with an error code).
+		 - {peer} may be NULL for incoming requests from unknown peers being rejected, otherwise it points to the peer structure associated with the attempt.
+		 - {other} is a char * pointer to the error message (human-readable).
+		 - {permsgdata} is always NULL for this hook.
+		 */
+	
+	HOOK_PEER_CONNECT_SUCCESS,
+		/* Hook called when a connection attempt to/from a remote peer has succeeded (the peer moves to OPEN_HANDSHAKE or OPEN state).
+		    In case of deprecated TLS handshake after the CER/CEA exchange, this hook can still be followed by HOOK_PEER_CONNECT_FAILED if TLS handshake fails.
+		 - {msg} points to the CEA message sent or received (with a success code) -- in case it is sent, you can always get access to the matching CER.
+		 - {peer} points to the peer structure.
+		 - {other} is NULL.
+		 - {permsgdata} is always NULL for this hook.
+		 */
+	
+	HOOK_MESSAGE_PARSING_ERROR2,
+		/* Hook called after an error message has been generated due to a dictionary parsing error.
+		 - {msg} points to the error message that has been generated.
+		 - {peer} is NULL. You can still retrieve the source from the message itself.
+		 - {other} is NULL
+		 - {permsgdata} points to existing structure associated with this message (or new structure if no previous hook was registered). 
+		 Use this hook if you need to populate more data in the error being returned, from the error message. 
+		 (e.g. some AVP need to be added to replies even if error case.
+		 */
+#define HOOK_LAST	HOOK_MESSAGE_PARSING_ERROR2
+};
+
+
+/* Type of the {permsgdata} pointer. It is up to each extension to define its own structure. This is opaque for the framework. */
+struct fd_hook_permsgdata;
+
+/* A handle that will be associated with the extension, and with the permsgdata structures. */
+struct fd_hook_data_hdl;
+
+/* The following structure is what is passed to the HOOK_DATA_RECEIVED hook */
+struct fd_cnx_rcvdata {
+	size_t  length;
+	uint8_t * buffer; /* internal note: the buffer is padded with a struct fd_msg_pmdl, not accounted for in length */
+};
+
+/* Function to register a new fd_hook_data_hdl. Should be called by your extension init function.
+ * The arguments are the functions called to initialize a new fd_hook_permsgdata and to free this structure when the corresponding message is being freed.
+ */
+/*
+ * FUNCTION:	fd_hook_data_register
+ *
+ * PARAMETERS:
+ *  permsgdata_size     : the size of the fd_hook_permsgdata structure. 
+ *  permsgdata_init_cb  : function called to initialize a new fd_hook_permsgdata structure, when a hook will be called for a message that does not have such structure yet. 
+ *                           The memory is already allocated and blanked, so you can pass NULL if no further handling is required.
+ *  permsgdata_fini_cb  : function called when a message is being disposed. It should free the resources associated with the fd_hook_permsgdata. 
+ *                           You can pass NULL if no special handling is required. The memory of the permsgdata structure itself will be freed by the framework.
+ *  new_handle          : On success, a handler to the registered callback is stored here. 
+ *		             This handler will be used to unregister the cb.
+ *
+ * DESCRIPTION: 
+ *   Register a new fd_hook_data_hdl. This handle is used during hooks registration (see below) in order to associate data with the messages, to allow keeping tracking of the message easily.
+ *  Note that these handlers are statically allocated and cannot be unregistered. FD_HOOK_HANDLE_LIMIT handlers can be registered at maximum (recompile libfdproto if you change this value)
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is registered.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOSPC	: Too many handles already registered. You may need to increase the limit in the code.
+ */
+int fd_hook_data_register(
+	size_t permsgdata_size,
+	void (*permsgdata_init_cb) (struct fd_hook_permsgdata *),
+        void (*permsgdata_fini_cb) (struct fd_hook_permsgdata *),
+        struct fd_hook_data_hdl **new_handle
+);
+
+/* A handler associated with a registered hook callback (for cleanup) */
+struct fd_hook_hdl; 
+
+/* Helper for building a mask of hooks for registration */
+#define HOOK_MASK(hooklist...)	fd_hook_mask_helper(0, ## hooklist, -1)
+
+/*
+ * FUNCTION:	fd_hook_register
+ *
+ * PARAMETERS:
+ *  type_mask	  : A bitmask of fd_hook_type bits for which this cb is registered, e.g. HOOK_MASK( HOOK_MESSAGE_RECEIVED, HOOK_MESSAGE_SENT )
+ *  fd_hook_cb	  : The callback function to register (see prototype above).
+ *  regdata	  : Pointer to pass to the callback when it is called. The data is opaque to the daemon.
+ *  data_hdl      : If permsgdata is requested for the hooks, a handler registered with fd_hook_data_register. NULL otherwise.
+ *  handler       : On success, a handler to the registered callback is stored here. 
+ *		   This handler can be used to unregister the cb.
+ *
+ * DESCRIPTION: 
+ *   Register a new hook in the framework. See explanations above.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is registered.
+ *  EEXIST      : Another callback is already registered for this type of hook (HOOK_DATA_RECEIVED).
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_hook_register (  uint32_t type_mask, 
+			void (*fd_hook_cb)(enum fd_hook_type type, struct msg * msg, struct peer_hdr * peer, void * other, struct fd_hook_permsgdata *pmd, void * regdata), 
+			void  *regdata, 
+			struct fd_hook_data_hdl *data_hdl,
+			struct fd_hook_hdl ** handler );
+
+/* Remove a hook registration */
+int fd_hook_unregister( struct fd_hook_hdl * handler );
+
+
+/* Use the following function to retrieve any pmd structure associated with a request matching the current answer. Returns NULL in case of error / no such structure */
+struct fd_hook_permsgdata * fd_hook_get_request_pmd(struct fd_hook_data_hdl *data_hdl, struct msg * answer);
+
+/* The following is used by HOOK_MASK macro */
+uint32_t fd_hook_mask_helper(int dummy, ...);
+
+/*============================================================*/
+
+/*
+ * The following allows an extension to retrieve stat information on the different fifo queues involved in the freeDiameter framework.
+ * There are three global queues, plus per-peer queues.
+ * This information can be used to build SNMP-like data for example, or quickly get a status of the framework to find the loaded path of execution / bottlenecks.
+ */
+enum fd_stat_type {
+	/* For the following, no peer is associated with the stat */
+	STAT_G_LOCAL= 1,	/* Get statistics for the global queue of messages processed by local extensions */
+	STAT_G_INCOMING,	/* Get statistics for the global queue of received messages to be processed by routing_in thread */
+	STAT_G_OUTGOING,	/* Get statistics for the global queue of messages to be processed by routing_out thread */
+	
+	/* For the following, the peer must be provided */
+	STAT_P_PSM,		/* Peer state machine queue (events to be processed for this peer, including received messages) */
+	STAT_P_TOSEND,		/* Queue of messages for sending to this peer */
+};
+
+/*
+ * FUNCTION:	fd_stat_getstats
+ *
+ * PARAMETERS:
+ *  stat	  : Which queue is being queried
+ *  peer	  : (depending on the stat parameter) which peer is being queried
+ *  current_count : (out) The number of items in the queue currently
+ *  limit_count   : (out) The max number of items the queue accepts before becoming blocking -- 0 means no max.
+ *  highest_count : (out) The highest count the queue has reached since startup
+ *  total_count	  : (out) Total number of items that this queue has processed (always growing, use deltas for monitoring)
+ *  total	  : (out) Cumulated time all items spent in this queue, including blocking time (always growing, use deltas for monitoring)
+ *  blocking      : (out) Cumulated time threads trying to post new items were blocked (queue full).
+ *  last          : (out) For the last element retrieved from the queue, how long it took between posting (including blocking) and poping
+ *  
+ * DESCRIPTION: 
+ *   Get statistics information about a given queue. 
+ *  Any of the (out) parameters can be NULL if not requested.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is registered.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_stat_getstats(enum fd_stat_type stat, struct peer_hdr * peer, 
+			int * current_count, int * limit_count, int * highest_count, long long * total_count,
+			struct timespec * total, struct timespec * blocking, struct timespec * last);
+
+/*============================================================*/
+/*                         EOF                                */
+/*============================================================*/
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _LIBFDCORE_H */