dsr_pkt_support.ex.c

opnet11.5 manet dsr和aodv协议

/* dsr_pkt_support.ex.c */
/* C support file for creation and deletion of DSR packets */


/****************************************/
/*		Copyright (c) 1987-2005			*/
/*		by OPNET Technologies, Inc.		*/
/*		(A Delaware Corporation)		*/
/*	7255 Woodmont Av., Suite 250  		*/
/*     Bethesda, MD 20814, U.S.A.       */
/*			All Rights Reserved.		*/
/****************************************/

/***** Includes *****/
#include <opnet.h>
#include <dsr.h>
#include <dsr_pkt_support.h>
#include <dsr_ptypes.h>
#include <ip_addr_v4.h>

/* Macro definition for string handling.	*/
#define DSR_PKPRINT_STRING_INSERT(str, contents, list)					\
	{										\
	str = (char*) op_prg_mem_alloc ((strlen (contents) + 1) * sizeof (char));	\
	strcpy (str, contents);								\
	op_prg_list_insert (list, str, OPC_LISTPOS_TAIL);				\
	}

/* File Globals	*/
static int 			fd_options_index = OPC_FIELD_INDEX_INVALID;

/**** Prototypes ****/
static List*							dsr_pkt_support_tlv_options_mem_copy (List* tlv_options_lptr);
static DsrT_Packet_Option*				dsr_pkt_support_route_request_mem_copy (DsrT_Packet_Option*);
static DsrT_Packet_Option*				dsr_pkt_support_route_reply_mem_copy (DsrT_Packet_Option*);
static DsrT_Packet_Option*				dsr_pkt_support_route_error_mem_copy (DsrT_Packet_Option*);
static DsrT_Packet_Option*				dsr_pkt_support_ack_request_mem_copy (DsrT_Packet_Option*);
static DsrT_Packet_Option*				dsr_pkt_support_acknowledgement_mem_copy (DsrT_Packet_Option*);
static DsrT_Packet_Option*				dsr_pkt_support_source_route_mem_copy (DsrT_Packet_Option*);

static void								dsr_pkt_support_tlv_options_mem_free (List* tlv_options_lptr);
static void								dsr_pkt_support_route_request_mem_free (DsrT_Packet_Option*);
static void								dsr_pkt_support_route_reply_mem_free (DsrT_Packet_Option*);
static void								dsr_pkt_support_route_error_mem_free (DsrT_Packet_Option*);
static void								dsr_pkt_support_ack_request_mem_free (DsrT_Packet_Option*);
static void								dsr_pkt_support_acknowledgement_mem_free (DsrT_Packet_Option*);
static void								dsr_pkt_support_source_route_mem_free (DsrT_Packet_Option*);

static DsrT_Packet_Option*				dsr_pkt_support_option_mem_alloc (void);
static DsrT_Route_Request_Option*		dsr_pkt_support_route_request_mem_alloc (void);
static DsrT_Route_Reply_Option*			dsr_pkt_support_route_reply_mem_alloc (void);
static DsrT_Route_Error_Option*			dsr_pkt_support_route_error_mem_alloc (void);
static DsrT_Acknowledgement_Request*	dsr_pkt_support_ack_request_mem_alloc (void);
static DsrT_Acknowledgement*			dsr_pkt_support_acknowledgement_mem_alloc (void);
static DsrT_Source_Route_Option*		dsr_pkt_support_source_route_mem_alloc (void);


/*****************************************************/
/************* PACKET CREATION FUNCTIONS *************/
/*****************************************************/

Packet*
dsr_pkt_support_pkt_create (int next_header)
	{
	Packet*					dsr_pkptr = OPC_NIL;
	List*					tlv_options_lptr = OPC_NIL;
	
	/** Create the DSR packet with the list of	**/
	/** options that are passed in. A single	**/
	/** packet can have multiple options		**/
	FIN (dsr_pkt_support_pkt_create (<args>));
	
	/* Create the DSR packet	*/
	dsr_pkptr = op_pk_create_fmt ("dsr");
	
	/* Create a list to store the options	*/
	tlv_options_lptr = op_prg_list_create ();
	
	/* Set the options in the packet	*/
	op_pk_nfd_set (dsr_pkptr, "Options", tlv_options_lptr, dsr_pkt_support_tlv_options_mem_copy, 
						dsr_pkt_support_tlv_options_mem_free, 0);
	
	/* Set the next header in the packet	*/
	/* The next header field of the DSR 	*/
	/* packet is set to the protocol field	*/
	/* of the IP datagram					*/
	op_pk_nfd_set (dsr_pkptr, "Next Header", next_header);
	
	FRET (dsr_pkptr);
	}


Packet*
dsr_pkt_support_pkt_create_with_options (int next_header, List* tlv_options_lptr)
	{
	Packet*					dsr_pkptr = OPC_NIL;
	DsrT_Packet_Option*		dsr_tlv_ptr = OPC_NIL;
	int						total_length = 0;
	int						num_options, count;
	
	/** Create the DSR packet with the list of	**/
	/** options that are passed in. A single	**/
	/** packet can have multiple options		**/
	FIN (dsr_pkt_support_pkt_create_with_options (<args>));
	
	/* Create the DSR packet	*/
	dsr_pkptr = op_pk_create_fmt ("dsr");
	
	/* Get the field index for the options field	*/
	if (fd_options_index == OPC_FIELD_INDEX_INVALID)
		fd_options_index = op_pk_nfd_name_to_index (dsr_pkptr, "Options");
	
	/* Determine the number of options in the list	*/
	num_options = op_prg_list_size (tlv_options_lptr);
	
	for (count = 0; count < num_options; count++)
		{
		/* Access each TLV in the list	*/
		/* to determine its size		*/
		dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_access (tlv_options_lptr, count);
		
		/* Get the total size of all the options	*/
		total_length += dsr_tlv_ptr->option_length;
		}
	
	/* Set the options in the packet	*/
	op_pk_fd_set (dsr_pkptr, fd_options_index, OPC_FIELD_TYPE_STRUCT, tlv_options_lptr, total_length,
					dsr_pkt_support_tlv_options_mem_copy, dsr_pkt_support_tlv_options_mem_free, sizeof (List));
	
	/* Set the next header in the packet	*/
	/* The next header field of the DSR 	*/
	/* packet is set to the protocol field	*/
	/* of the IP datagram					*/
	op_pk_nfd_set (dsr_pkptr, "Next Header", next_header);
	
	FRET (dsr_pkptr);
	}


void
dsr_pkt_support_option_add (Packet* dsr_pkptr, DsrT_Packet_Option* dsr_tlv_ptr)
	{
	int						total_length = 0;
	OpT_Packet_Size			field_size = 0;
	List*					tlv_options_lptr = OPC_NIL;
	int						num_options, count;
	DsrT_Packet_Option*		exist_dsr_tlv_ptr = OPC_NIL;
	Boolean					option_inserted = OPC_FALSE;
	
	/** Add an option to the DSR packet	**/
	FIN (dsr_pkt_support_option_add (<args>));

	/* Get the field index for the options field	*/
	if (fd_options_index == OPC_FIELD_INDEX_INVALID)
		fd_options_index = op_pk_nfd_name_to_index (dsr_pkptr, "Options");
		
	/* Determine the size of the field, before we strip it 	*/
	/* from the packet.										*/
	field_size = (int) op_pk_fd_size (dsr_pkptr, fd_options_index);
	
	/* Get the list of options	*/
	op_pk_fd_get (dsr_pkptr, fd_options_index, &tlv_options_lptr);

	/* Determine the number of options in the list	*/
	num_options = op_prg_list_size (tlv_options_lptr);
   	
	/* Determine the total length of the options field	*/
	/* with the new option added						*/
	total_length = field_size + dsr_tlv_ptr->option_length;
	
	/* Insert the new option into the list	*/
	/* Always insert all options before the	*/
	/* source route option					*/
	for (count = 0; count < num_options; count++)
		{
		/* Access each TLV in the list	*/
		exist_dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_access (tlv_options_lptr, count);
		
		if (exist_dsr_tlv_ptr->option_type == DSRC_SOURCE_ROUTE)
			{
			/* Insert before the source route option	*/
			op_prg_list_insert (tlv_options_lptr, dsr_tlv_ptr, count);
			
			option_inserted = OPC_TRUE;
			
			break;
			}
		}
	
	if (option_inserted == OPC_FALSE)
		{
		/* There is no source route in the packet	*/
		/* Insert the option at the end of the list	*/
		op_prg_list_insert (tlv_options_lptr, dsr_tlv_ptr, OPC_LISTPOS_TAIL);
		}
	
	/* Set the options in the packet	*/
	op_pk_fd_set (dsr_pkptr, fd_options_index, OPC_FIELD_TYPE_STRUCT, tlv_options_lptr, total_length,
					dsr_pkt_support_tlv_options_mem_copy, dsr_pkt_support_tlv_options_mem_free, sizeof (List));
	
	FOUT;
	}


void
dsr_pkt_support_option_remove (Packet* dsr_pkptr, int option_type)
	{
	int						num_options, count;
	int						total_length = 0;
	DsrT_Packet_Option*		dsr_tlv_ptr = OPC_NIL;
	List*					tlv_options_lptr = OPC_NIL;
	List*					temp_lptr = OPC_NIL;
	
	/** Removes a specific option from the DSR	**/
	/** packet and sets its size accordingly	**/
	/** There should only be one option of that	**/
	/** type in the DSR packet header			**/
	FIN (dsr_pkt_support_option_remove (<args>));
	
	/* Get the field index for the options field	*/
	if (fd_options_index == OPC_FIELD_INDEX_INVALID)
		fd_options_index = op_pk_nfd_name_to_index (dsr_pkptr, "Options");
	
	/* Get the list of options	*/
	op_pk_nfd_get (dsr_pkptr, "Options", &tlv_options_lptr);
	
	/* Determine the number of options in the list	*/
	num_options = op_prg_list_size (tlv_options_lptr);
	
	for (count = 0; count < num_options; count++)
		{
		/* Access each TLV in the list	*/
		dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_access (tlv_options_lptr, count);
		
		if (dsr_tlv_ptr->option_type == option_type)
			{
			/* Remove the matching option from the	*/
			/* list of options in the packet		*/
			dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_remove (tlv_options_lptr, count);
			
			/* Free the memory	*/
			temp_lptr = op_prg_list_create ();
			op_prg_list_insert (temp_lptr, dsr_tlv_ptr, OPC_LISTPOS_TAIL);
			dsr_pkt_support_tlv_options_mem_free (temp_lptr);
			
			break;
			}
		}
	
	/* Reset the size of the packet based on the options remaining	*/
	num_options = op_prg_list_size (tlv_options_lptr);
	
	for (count = 0; count < num_options; count++)
		{
		/* Access each TLV in the list	*/
		/* to determine its size		*/
		dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_access (tlv_options_lptr, count);
		
		/* Get the total size of all the options	*/
		total_length += dsr_tlv_ptr->option_length;
		}
	
	/* Set the options in the packet	*/
	op_pk_fd_set (dsr_pkptr, fd_options_index, OPC_FIELD_TYPE_STRUCT, tlv_options_lptr, total_length,
					dsr_pkt_support_tlv_options_mem_copy, dsr_pkt_support_tlv_options_mem_free, sizeof (List));
	
	FOUT;
	}


/*****************************************************/
/************* PACKET SUPPORT FUNCTIONS **************/
/*****************************************************/

void
dsr_pkt_support_route_request_hop_insert (Packet* ip_pkptr, InetT_Address node_address)
	{
	List*								tlv_options_lptr = OPC_NIL;
	Packet*								dsr_pkptr = OPC_NIL;
	DsrT_Packet_Option* 				dsr_tlv_ptr = OPC_NIL;
	DsrT_Route_Request_Option*			route_request_ptr = OPC_NIL;
	int									num_hops, count, num_options;
	int									total_length = 0;
	int									address_length;
	InetT_Address*						copy_address_ptr = OPC_NIL;
	OpT_Packet_Size						dsr_pkt_size;
		
	/** Inserts the hop address into the list of hops	**/
	/** traversed by this route request					**/
	FIN (dsr_pkt_support_route_request_hop_insert (<args>));
	
	/* Get the DSR packet from the IP datagram	*/
	op_pk_nfd_get (ip_pkptr, "data", &dsr_pkptr);
	
	/* Get the list of options	*/
	op_pk_nfd_get (dsr_pkptr, "Options", &tlv_options_lptr);
	
	/* Get the number of options	*/
	num_options = op_prg_list_size (tlv_options_lptr);
	
	for (count = 0; count < num_options; count++)
		{
		dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_access (tlv_options_lptr, count);
		
		if (dsr_tlv_ptr->option_type == DSRC_ROUTE_REQUEST)
			break;
		}

	/* Get a handle to route request structure	*/
	route_request_ptr = (DsrT_Route_Request_Option*) dsr_tlv_ptr->dsr_option_ptr;
	
	/* Set the node address in the hop list	*/
	copy_address_ptr = inet_address_create_dynamic (node_address);
	op_prg_list_insert (route_request_ptr->route_lptr, copy_address_ptr, OPC_LISTPOS_TAIL);
	
	/* Determine the size of the options field	*/
	address_length = (inet_address_family_get (copy_address_ptr) == InetC_Addr_Family_v4 ? IP_V4_ADDRESS_LENGTH : IP_V6_ADDRESS_LENGTH);
	num_hops = op_prg_list_size (route_request_ptr->route_lptr);
	dsr_tlv_ptr->option_length = DSR_HEADER_OPTIONS + (num_hops + 1) * address_length;
	
	/* Calculate the length of the options field   */
	for (count = 0; count < num_options; count++)
		{
		dsr_tlv_ptr = (DsrT_Packet_Option*) op_prg_list_access (tlv_options_lptr, count);
		total_length += dsr_tlv_ptr->option_length;
		}
	
	/* Set the options in the packet	*/
	op_pk_fd_set (dsr_pkptr, fd_options_index, OPC_FIELD_TYPE_STRUCT, tlv_options_lptr, total_length,
					dsr_pkt_support_tlv_options_mem_copy, dsr_pkt_support_tlv_options_mem_free, sizeof (List));
	
	/* Get new dsr packet size 							*/
	dsr_pkt_size = op_pk_total_size_get (dsr_pkptr);

	/* Set the DSR packet in the IP datagram			*/
	op_pk_nfd_set (ip_pkptr, "data", dsr_pkptr);

	/* Set the bulk size of the IP packet to model		*/
	/* the space occupied by the encapsulated data. 	*/
	op_pk_bulk_size_set (ip_pkptr, dsr_pkt_size);
	
	FOUT;
	}


InetT_Address
dsr_pkt_support_source_route_hop_obtain (DsrT_Source_Route_Option* source_route_ptr, DsrT_Hop_Type hop_type, InetT_Address src_addr, InetT_Address dest_addr)
	{
	InetT_Address*					next_hop_address_ptr;
	int								num_hops;
	int								access_number;
	
	/** Obtains the current or next hop in the 		**/
	/** source route and decrements the segments  	**/
	/** left in the source route option of the TLV  **/
	/** if the next hop is accessed					**/
	FIN (dsr_pkt_support_source_route_hop_obtain (<args>));
	
	/* Total number of hops	not including the source	*/
	/* and destination node (only intermediate nodes)	*/
	num_hops = op_prg_list_size (source_route_ptr->route_lptr);
	
	if (hop_type == DsrC_Previous_Hop)
		{
		/* Get the previous hop node from which	*/
		/* this node received the packet		*/
		access_number = num_hops - source_route_ptr->segments_left - 1;
		}
	else if (hop_type == DsrC_Current_Hop)
		{
		/* Get the current node interface address	*/
		access_number = num_hops - source_route_ptr->segments_left;
		}
	else if (hop_type == DsrC_Next_Hop)
		{
		/* Decrement the segments left to visit	*/
		/* if we are accessing the next hop		*/
		source_route_ptr->segments_left--;
		access_number = num_hops - source_route_ptr->segments_left;
		}
	
	if (access_number < 0)
		{
		/* Return the source address	*/