Initial commit

Change-Id: I6a4444e3c193dae437cd7929f4c39aba7b749efa
diff --git a/libfdcore/p_dp.c b/libfdcore/p_dp.c
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+++ b/libfdcore/p_dp.c
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+/*********************************************************************************************************
+* Software License Agreement (BSD License)                                                               *
+* Author: Sebastien Decugis <sdecugis@freediameter.net>							 *
+*													 *
+* Copyright (c) 2013, 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.								 *
+*********************************************************************************************************/
+
+#include "fdcore-internal.h"
+
+/* This file contains code to handle Disconnect Peer messages (DPR and DPA) */
+
+/* Delay to use before next reconnect attempt */
+int fd_p_dp_newdelay(struct fd_peer * peer) 
+{
+	int delay = peer->p_hdr.info.config.pic_tctimer ?: fd_g_config->cnf_timer_tc;
+	
+	switch (peer->p_hdr.info.runtime.pir_lastDC) {
+		case ACV_DC_REBOOTING:
+		default:
+			/* We use TcTimer to attempt reconnection */
+			break;
+		case ACV_DC_BUSY:
+			/* No need to hammer the overloaded peer */
+			delay *= 10;
+			break;
+		case ACV_DC_NOT_FRIEND:
+			/* He does not want to speak to us... let's retry a *lot* later maybe */
+			delay *= 200;
+			break;
+	}
+	return delay;
+}
+
+/* Handle a received message */
+int fd_p_dp_handle(struct msg ** msg, int req, struct fd_peer * peer)
+{
+	long to_receive, to_send;
+	TRACE_ENTRY("%p %d %p", msg, req, peer);
+	
+	if (req) {
+		/* We received a DPR, save the Disconnect-Cause and go to CLOSING_GRACE or terminate the connection */
+		struct avp * dc;
+		
+		CHECK_FCT( fd_msg_search_avp ( *msg, fd_dict_avp_DC, &dc ));
+		if (dc) {
+			struct avp_hdr * hdr;
+			CHECK_FCT(  fd_msg_avp_hdr( dc, &hdr )  );
+			if (hdr->avp_value == NULL) {
+				/* This is a sanity check */
+				LOG_F("BUG: Unset value in Disconnect-Cause in DPR");
+				ASSERT(0); /* To check if this really happens, and understand why... */
+			}
+
+			/* save the cause */
+			peer->p_hdr.info.runtime.pir_lastDC = hdr->avp_value->u32;
+		}
+		if (TRACE_BOOL(INFO)) {
+			if (dc) {
+				struct dict_object * dictobj;
+				struct dict_enumval_request er;
+				memset(&er, 0, sizeof(er));
+				
+				/* prepare the request */
+				CHECK_FCT( fd_dict_search( fd_g_config->cnf_dict, DICT_TYPE, TYPE_OF_AVP, fd_dict_avp_DC, &er.type_obj, ENOENT )  );
+				er.search.enum_value.u32 = peer->p_hdr.info.runtime.pir_lastDC;
+				
+				/* Search the enum value */
+				CHECK_FCT( fd_dict_search( fd_g_config->cnf_dict, DICT_ENUMVAL, ENUMVAL_BY_STRUCT, &er, &dictobj, 0 )  );
+				if (dictobj) {
+					CHECK_FCT( fd_dict_getval( dictobj, &er.search ) );
+					TRACE_DEBUG(INFO, "Peer '%s' sent a DPR with cause: %s", peer->p_hdr.info.pi_diamid, er.search.enum_name);
+				} else {
+					TRACE_DEBUG(INFO, "Peer '%s' sent a DPR with unknown cause: %u", peer->p_hdr.info.pi_diamid, peer->p_hdr.info.runtime.pir_lastDC);
+				}
+			} else {
+				TRACE_DEBUG(INFO, "Peer '%s' sent a DPR without Disconnect-Cause AVP", peer->p_hdr.info.pi_diamid);
+			}
+		}
+		
+		/* Now reply with a DPA */
+		CHECK_FCT( fd_msg_new_answer_from_req ( fd_g_config->cnf_dict, msg, 0 ) );
+		CHECK_FCT( fd_msg_rescode_set( *msg, "DIAMETER_SUCCESS", NULL, NULL, 1 ) );
+		
+		/* Do we have pending exchanges with this peer? */
+		CHECK_FCT( fd_peer_get_load_pending(&peer->p_hdr, &to_receive, &to_send) );
+		
+		if ((to_receive == 0) && (to_send == 0)) {
+			/* No pending exchange, move to CLOSING directly */
+			CHECK_FCT( fd_psm_change_state(peer, STATE_CLOSING) );
+		
+			/* Now send the DPA */
+			CHECK_FCT( fd_out_send( msg, NULL, peer, 0) );
+			
+			/* and move to CLOSED */
+			fd_psm_cleanup(peer, 0);
+
+			/* Reset the timer for next connection attempt -- we'll retry sooner or later depending on the disconnection cause */
+			fd_psm_next_timeout(peer, 1, fd_p_dp_newdelay(peer));
+		} else {
+			/* We have pending exchanges, we move to CLOSING_GRACE which allows exchanges of answers but
+			not new requests */
+			CHECK_FCT( fd_psm_change_state(peer, STATE_CLOSING_GRACE) );
+			fd_psm_next_timeout(peer, 0, GRACE_TIMEOUT);
+			
+			/* Now send the DPA */
+			CHECK_FCT( fd_out_send( msg, NULL, peer, 0) );
+		}
+	} else {
+		/* We received a DPA */
+		int curstate = fd_peer_getstate(peer);
+		if (curstate != STATE_CLOSING_GRACE) {
+			TRACE_DEBUG(INFO, "Ignoring DPA received in state %s", STATE_STR(curstate));
+		}
+			
+		/* In theory, we should control the Result-Code AVP. But since we will not go back to OPEN state here anyway, let's skip it */
+		
+		/* TODO("Control Result-Code in the DPA") */
+		CHECK_FCT_DO( fd_msg_free( *msg ), /* continue */ );
+		*msg = NULL;
+		
+		/* Do we still have pending exchanges with this peer? */
+		CHECK_FCT( fd_peer_get_load_pending(&peer->p_hdr, &to_receive, &to_send) );
+		if ((to_receive != 0) || (to_send != 0)) {
+			TRACE_DEBUG(INFO, "Received DPA but pending load: [%ld, %ld], giving grace delay before closing", to_receive, to_send);
+			fd_psm_next_timeout(peer, 0, GRACE_TIMEOUT);
+			peer->p_flags.pf_localterm = 1;
+		} else {
+			/* otherwise, go to CLOSING state, the psm will handle terminating the connection */
+			CHECK_FCT( fd_psm_change_state(peer, STATE_CLOSING) );
+		}
+	}
+	
+	return 0;
+}
+
+/* Start disconnection of a peer: send DPR */
+int fd_p_dp_initiate(struct fd_peer * peer, char * reason)
+{
+	struct msg * msg = NULL;
+	struct dict_object * dictobj = NULL;
+	struct avp * avp = NULL;
+	struct dict_enumval_request er;
+	union avp_value val;
+	
+	TRACE_ENTRY("%p %p", peer, reason);
+	
+	/* Create a new DWR instance */
+	CHECK_FCT( fd_msg_new ( fd_dict_cmd_DPR, MSGFL_ALLOC_ETEID, &msg ) );
+	
+	/* Add the Origin information */
+	CHECK_FCT( fd_msg_add_origin ( msg, 0 ) );
+	
+	/* Add the Disconnect-Cause */
+	CHECK_FCT( fd_msg_avp_new ( fd_dict_avp_DC, 0, &avp ) );
+	
+	/* Search the value in the dictionary */
+	memset(&er, 0, sizeof(er));
+	CHECK_FCT( fd_dict_search( fd_g_config->cnf_dict, DICT_TYPE, TYPE_OF_AVP, fd_dict_avp_DC, &er.type_obj, ENOENT )  );
+	er.search.enum_name = reason ?: "REBOOTING";
+	CHECK_FCT_DO( fd_dict_search( fd_g_config->cnf_dict, DICT_ENUMVAL, ENUMVAL_BY_STRUCT, &er, &dictobj, ENOENT ), { ASSERT(0); /* internal error: unknown reason */ }  );
+	CHECK_FCT( fd_dict_getval( dictobj, &er.search ) );
+	
+	/* Set the value in the AVP */
+	val.u32 = er.search.enum_value.u32;
+	CHECK_FCT( fd_msg_avp_setvalue( avp, &val ) );
+	CHECK_FCT( fd_msg_avp_add( msg, MSG_BRW_LAST_CHILD, avp ) );
+	
+	/* Save the value also in the peer */
+	peer->p_hdr.info.runtime.pir_lastDC = val.u32;
+	
+	/* Update the peer state and timer */
+	CHECK_FCT( fd_psm_change_state(peer, STATE_CLOSING_GRACE) );
+	fd_psm_next_timeout(peer, 0, DPR_TIMEOUT);
+	
+	/* Now send the DPR message */
+	CHECK_FCT_DO( fd_out_send(&msg, NULL, peer, 0), /* ignore since we are on timeout anyway */ );
+	
+	return 0;
+}