statable.c

一个学习SNMP项目：tmoerlan.

/*	Copyright (c) 2003, Tijmen Moerland <[e-mail]>
	Code is licensed under the BSD license.
*/

/*!	\file staTable.c
	\brief Implements the l80211IfaceStaTable table.
		
	Since the structure of this implementation is similar to if80211Table.c, please refer to that file.
	Do note that this table is double-indexed, the first index being the wireless interface number, the second a simple increasing counter starting at one indicating the station on which information is available.

	Also refer to the comments within the code.
*/
/*
 * Note: this file originally auto-generated by mib2c using
 *        : mib2c.iterate.conf,v 5.4 2002/09/11 22:42:04 hardaker Exp $
 */

#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include "staTable.h"
#include "lib80211.h"
#include <sys/time.h>
#include <sys/timeb.h>

#define CACHETIME 5	 // seconds


struct staInfo {
	long index;
	struct wi_sigextcache *cache;
	int assoc;	//1 = true, 2 = false;
	int auth;	//1 = true, 2 = false;
};

struct ifaceInfo {
	struct wi_sigextcache *sigextcache;
	int wi_sigitems;
	struct timeval cacheTimeStamp;

	struct staInfo sta[MAXWICACHE];	/* this should be WIHAP_MAX_STATIONS, but we can only have
					MAXWICACHE stations in the cache per interface anyway */
};

struct ifaceInfo ifaceInfoList[IF_MAXNR];

long global_index, if_index;
long if_nr;


/** Initialize the staTable table by defining its contents and how it's structured */
void
initialize_table_staTable(void)
{
    static oid staTable_oid[] = {1,3,6,1,4,1,18003,2,1,1,4};
    netsnmp_table_registration_info *table_info;
    netsnmp_handler_registration *my_handler;
    netsnmp_iterator_info *iinfo;

    /* create the table structure itself */
    table_info = SNMP_MALLOC_TYPEDEF(netsnmp_table_registration_info);
    iinfo = SNMP_MALLOC_TYPEDEF(netsnmp_iterator_info);

    /* if your table is read only, it's easiest to change the
       HANDLER_CAN_RWRITE definition below to HANDLER_CAN_RONLY */
    my_handler = netsnmp_create_handler_registration("staTable",
                                             staTable_handler,
                                             staTable_oid,
                                             OID_LENGTH(staTable_oid),
                                             HANDLER_CAN_RWRITE);
            
    if (!my_handler || !table_info || !iinfo)
        return; /* mallocs failed */

    /***************************************************
     * Setting up the table's definition
     */
    netsnmp_table_helper_add_indexes(table_info,
                                  ASN_INTEGER, /* index: ifIndex */
				  ASN_INTEGER, /* index: l80211StaIndex */
                             0);

    table_info->min_column = 2;
    table_info->max_column = 23;

    /* iterator access routines */
    iinfo->get_first_data_point = staTable_get_first_data_point;
    iinfo->get_next_data_point = staTable_get_next_data_point;
//    iinfo->free_loop_contet = staTable_free_loop_context;

    iinfo->table_reginfo = table_info;

    /***************************************************
     * registering the table with the master agent
     */
    DEBUGMSGTL(("staTable",
                "Registering table staTable as a table iterator\n"));		 
    netsnmp_register_table_iterator(my_handler, iinfo);
 
    bzero((char *) ifaceInfoList, IF_MAXNR * sizeof(struct ifaceInfo));
}

/** Initializes the staTable module */
void
init_staTable(void)
{

  /* here we initialize all the tables we're planning on supporting */
    initialize_table_staTable();
}

netsnmp_variable_list *
staTable_get_first_data_point(void **my_loop_context, void **my_data_context,
                          netsnmp_variable_list *put_index_data,
                          netsnmp_iterator_info *mydata)
{
	int i, flags = 0;
	char buf[IF_NAMELEN];
	struct timeval now;
	
    	netsnmp_variable_list *vptr;

//init index	
	global_index = 1;	//start from index 1
	if_index = 0;
	if_nr = getNumIf80211();

	struct ifaceInfo *currIface;
	
	if (if_nr <= 0)
		return NULL;

	do
	{
		if_index++;

		currIface = &ifaceInfoList[if_index-1];
		gettimeofday(&now, NULL);
        	if (now.tv_sec - currIface->cacheTimeStamp.tv_sec >= CACHETIME) {
                	DEBUGMSGTL(("staTable", "old copy = %ld, getting fresh copy of extcache: %ld\n", currIface->cacheTimeStamp.tv_sec,
                        	now.tv_sec));
	    		currIface->wi_sigitems = getCacheItemnr(getNameIf80211(if_index, buf));
			if (currIface->wi_sigitems > 0) {
				if (currIface->sigextcache != NULL)
					free(currIface->sigextcache);
				currIface->sigextcache = (struct wi_sigextcache *) malloc(currIface->wi_sigitems * sizeof(struct wi_sigextcache));
				getExtendedCache(getNameIf80211(if_index, buf), currIface->sigextcache, currIface->wi_sigitems);
                	}
			currIface->cacheTimeStamp.tv_sec = now.tv_sec;
	                currIface->cacheTimeStamp.tv_usec = now.tv_usec;
        	}
	        else {
        	        DEBUGMSGTL(("staTable", "using old copy of extcache, age=%f seconds\n",
                	        now.tv_sec - currIface->cacheTimeStamp.tv_sec +
                        	1e-6 * (now.tv_usec - currIface->cacheTimeStamp.tv_usec)));
	        }

	}	while (if_index < if_nr && currIface->wi_sigitems <= 0);

	DEBUGMSGTL(("staTable", "found index %d\n", if_index));

	if (if_index > if_nr)	//all interfaces where have no cache items
		return NULL;

//put the pointer to this cache into the corresponding staInfoList
	currIface->sta[global_index].index = global_index;
	currIface->sta[global_index].cache = currIface->sigextcache + (global_index-1)*sizeof(struct wi_sigextcache);
//now we need to find out about assoc and auth
//if the same mac address from the cache is found in the
//active stations list we can look up assoc/auth
//if not, both are false
//the next function returns the flags for this station, and 0 if
//station is not in the list
	flags = getStaFlags(getNameIf80211(if_index, buf), currIface->sta[global_index].cache->macsrc);
	if (flags & HOSTAP_FLAGS_ASSOC)
		currIface->sta[global_index].assoc = 1;
	else
		currIface->sta[global_index].assoc = 2;
	if (flags & HOSTAP_FLAGS_AUTHEN)
		currIface->sta[global_index].auth = 1;
	else
		currIface->sta[global_index].auth = 2;

    *my_loop_context = (void *) &global_index;
    *my_data_context = (void *) &currIface->sta[global_index];

//    DEBUGMSGTL(("staTable", "START: index=(%ld, %ld)\n", global_index, if_index));

    vptr = put_index_data;
    
    static long ifIndex;
    ifIndex = getPtrIf80211(if_index); 
    snmp_set_var_value(vptr, (u_char *) &ifIndex, sizeof(long));
    vptr = vptr->next_variable;
    snmp_set_var_value(vptr, (u_char *) &global_index, sizeof(long));

    return put_index_data;
}

netsnmp_variable_list *
staTable_get_next_data_point(void **my_loop_context, void **my_data_context,
                         netsnmp_variable_list *put_index_data,
                         netsnmp_iterator_info *mydata)
{
	int flags = 0;
	char buf[IF_NAMELEN];
	struct timeval now;
	
	struct ifaceInfo *currIface = &ifaceInfoList[if_index - 1];

    netsnmp_variable_list *vptr;

//	DEBUGMSGTL(("staTable", "start of get_next_data_point"));
	DEBUGMSGTL(("staTable", "*wi_sigitems=%d\n", currIface->wi_sigitems));
	if (global_index >= currIface->wi_sigitems) {
		//if there's no more data left,
		//we leave loop_context and data_context alone
		//and return NULL;
		DEBUGMSGTL(("staTable", "done all cache items for iface %d\n", if_index));
		if (if_index >= if_nr)
	    		return NULL;
		else {

			DEBUGMSGTL(("staTable", "searching for next iface with cache items...\n"));
			do {
				if_index++;
				DEBUGMSGTL(("staTable", "trying %d\t", if_index));
				currIface = &ifaceInfoList[if_index-1];
				gettimeofday(&now, NULL);
        	                if (now.tv_sec - currIface->cacheTimeStamp.tv_sec >= CACHETIME) {
                	                DEBUGMSGTL(("staTable", "old copy = %ld, getting fresh copy of extcache: %ld\n", currIface->cacheTimeStamp.tv_sec,
			              	                now.tv_sec));
					currIface->wi_sigitems = getCacheItemnr(getNameIf80211(if_index, buf));
		                        if (currIface->wi_sigitems > 0) {
                		                if (currIface->sigextcache != NULL)
		                                        free(currIface->sigextcache);
						currIface->sigextcache = (struct wi_sigextcache *) malloc(currIface->wi_sigitems * sizeof(struct wi_sigextcache));
                                		getExtendedCache(getNameIf80211(if_index, buf), currIface->sigextcache, currIface->wi_sigitems);
 					}                       
 	                                currIface->cacheTimeStamp.tv_sec = now.tv_sec;
        	                        currIface->cacheTimeStamp.tv_usec = now.tv_usec;
                	        }
                        	else {
                                	DEBUGMSGTL(("staTable", "using old copy of extcache, age=%f seconds\n",
                                        	now.tv_sec - currIface->cacheTimeStamp.tv_sec +
                                        	1e-6 * (now.tv_usec - currIface->cacheTimeStamp.tv_usec)));
	                        }
				DEBUGMSGTL(("staTable", "sigitems=%d\n", currIface->wi_sigitems));
			} while (if_index < if_nr && currIface->wi_sigitems <= 0);
			if (if_index > if_nr)
				return NULL;
			global_index = 1;
		}
	}
	else {
		global_index++;
//		currIface->sigextcache++;
	}

	DEBUGMSGTL(("staTable", "next: doing iface %d, station %d: %x:%x:%x\n", if_index, global_index, 
		currIface->sigextcache->macsrc[1]&0xff, currIface->sigextcache->macsrc[2]&0xff, 
		currIface->sigextcache->macsrc[2]&0xff));
//put the pointer to this cache into the corresponding staInfoList
	currIface->sta[global_index].index = global_index;
	currIface->sta[global_index].cache = currIface->sigextcache + (global_index-1);
//now we need to find out about assoc and auth
//if the same mac address from the cache is found in the
//active stations list we can look up assoc/auth
//if not, both are false
//the next function returns the flags for this station, and 0 if
//station is not in the list
	flags = getStaFlags(getNameIf80211(if_index, buf), currIface->sta[global_index].cache->macsrc);
	if (flags & HOSTAP_FLAGS_ASSOC)
                currIface->sta[global_index].assoc = 1;
        else
                currIface->sta[global_index].assoc = 2;
        if (flags & HOSTAP_FLAGS_AUTHEN)
                currIface->sta[global_index].auth = 1;
        else
                currIface->sta[global_index].auth = 2;

		
    *my_loop_context = (void *) &global_index;
    *my_data_context = (void *) &currIface->sta[global_index];