agent/mibgroup/mibII/udp.c - vendor/opensource/netsnmp - Git at Google

 /*
  *  UDP MIB group implementation - udp.c
  *
  */

 #include <net-snmp/net-snmp-config.h>
 #include "mibII_common.h"

 #ifdef HAVE_NETINET_UDP_H
 #include <netinet/udp.h>
 #endif
 #if HAVE_NETINET_UDP_VAR_H
 #include <netinet/udp_var.h>
 #endif

 #include <net-snmp/net-snmp-includes.h>
 #include <net-snmp/agent/net-snmp-agent-includes.h>
 #include <net-snmp/agent/auto_nlist.h>
 #include <net-snmp/agent/sysORTable.h>

 #include "util_funcs/MIB_STATS_CACHE_TIMEOUT.h"

 #ifdef linux
 #include "tcp.h"
 #endif
 #include "udp.h"
 #include "udpTable.h"

 #ifdef NETSNMP_CAN_USE_SYSCTL
 #include <sys/sysctl.h>
 #endif

 #ifndef MIB_STATS_CACHE_TIMEOUT
 #define MIB_STATS_CACHE_TIMEOUT	5
 #endif
 #ifndef UDP_STATS_CACHE_TIMEOUT
 #define UDP_STATS_CACHE_TIMEOUT	MIB_STATS_CACHE_TIMEOUT
 #endif

 #if defined(HAVE_LIBPERFSTAT_H) && (defined(aix4) || defined(aix5) || defined(aix6) || defined(aix7)) && !defined(FIRST_PROTOCOL)
 #ifdef HAVE_SYS_PROTOSW_H
 #include <sys/protosw.h>
 #endif
 #include <libperfstat.h>
 #ifdef FIRST_PROTOCOL
 perfstat_protocol_t ps_proto;
 perfstat_id_t ps_name;
 #define _USE_PERFSTAT_PROTOCOL 1
 #endif
 #endif

         /*********************
 	 *
 	 *  Kernel & interface information,
 	 *   and internal forward declarations
 	 *
 	 *********************/


         /*********************
 	 *
 	 *  Initialisation & common implementation functions
 	 *
 	 *********************/

 /*
  * Define the OID pointer to the top of the mib tree that we're
  * registering underneath, and the OID for the MIB module
  */
 oid             udp_oid[]               = { SNMP_OID_MIB2, 7 };
 oid             udp_module_oid[]        = { SNMP_OID_MIB2, 50 };

 void
 init_udp(void)
 {
     netsnmp_handler_registration *reginfo;
     int rc;

     /*
      * register ourselves with the agent as a group of scalars...
      */
     DEBUGMSGTL(("mibII/udpScalar", "Initialising UDP scalar group\n"));
     reginfo = netsnmp_create_handler_registration("udp", udp_handler,
 		    udp_oid, OID_LENGTH(udp_oid), HANDLER_CAN_RONLY);
     rc = netsnmp_register_scalar_group(reginfo, UDPINDATAGRAMS, UDPOUTDATAGRAMS);
     if (rc != SNMPERR_SUCCESS)
         return;

     /*
      * .... with a local cache
      *    (except for HP-UX 11, which extracts objects individually)
      */
 #ifndef hpux11
     netsnmp_inject_handler( reginfo,
 		    netsnmp_get_cache_handler(UDP_STATS_CACHE_TIMEOUT,
 			   		udp_load, udp_free,
 					udp_oid, OID_LENGTH(udp_oid)));
 #endif

     REGISTER_SYSOR_ENTRY(udp_module_oid,
                          "The MIB module for managing UDP implementations");

 #if !defined(_USE_PERFSTAT_PROTOCOL)
 #ifdef UDPSTAT_SYMBOL
     auto_nlist(UDPSTAT_SYMBOL, 0, 0);
 #endif
 #ifdef UDB_SYMBOL
     auto_nlist(UDB_SYMBOL, 0, 0);
 #endif
 #ifdef solaris2
     init_kernel_sunos5();
 #endif
 #endif
 }


         /*********************
 	 *
 	 *  System specific implementation functions
 	 *
 	 *********************/

 #ifdef hpux11
 #define UDP_STAT_STRUCTURE	int
 #endif

 #ifdef linux
 #define UDP_STAT_STRUCTURE	struct udp_mib
 #define USES_SNMP_DESIGNED_UDPSTAT
 #undef UDPSTAT_SYMBOL
 #endif

 #ifdef solaris2
 #define UDP_STAT_STRUCTURE	mib2_udp_t
 #define USES_SNMP_DESIGNED_UDPSTAT
 #endif

 #ifdef NETBSD_STATS_VIA_SYSCTL
 #define UDP_STAT_STRUCTURE      struct udp_mib
 #define USES_SNMP_DESIGNED_UDPSTAT
 #undef UDP_NSTATS
 #endif

 #ifdef HAVE_IPHLPAPI_H
 #include <iphlpapi.h>
 #define UDP_STAT_STRUCTURE MIB_UDPSTATS
 #endif

 #ifdef HAVE_SYS_TCPIPSTATS_H
 #define UDP_STAT_STRUCTURE	struct kna
 #define USES_TRADITIONAL_UDPSTAT
 #endif


 #if !defined(UDP_STAT_STRUCTURE)
 #define UDP_STAT_STRUCTURE	struct udpstat
 #define USES_TRADITIONAL_UDPSTAT
 #endif

 UDP_STAT_STRUCTURE udpstat;


         /*********************
 	 *
 	 *  System independent handler (mostly)
 	 *
 	 *********************/


 int
 udp_handler(netsnmp_mib_handler          *handler,
             netsnmp_handler_registration *reginfo,
             netsnmp_agent_request_info   *reqinfo,
             netsnmp_request_info         *requests)
 {
     netsnmp_request_info  *request;
     netsnmp_variable_list *requestvb;
     long     ret_value = -1;
     oid      subid;
     int      type = ASN_COUNTER;

     /*
      * The cached data should already have been loaded by the
      *    cache handler, higher up the handler chain.
      * But just to be safe, check this and load it manually if necessary
      */
 #if defined(_USE_PERFSTAT_PROTOCOL)
     udp_load(NULL, NULL);
 #endif


     /*
      *
      *
      */
     DEBUGMSGTL(("mibII/udpScalar", "Handler - mode %s\n",
                     se_find_label_in_slist("agent_mode", reqinfo->mode)));
     switch (reqinfo->mode) {
     case MODE_GET:
         for (request=requests; request; request=request->next) {
             requestvb = request->requestvb;
             subid = requestvb->name[OID_LENGTH(udp_oid)];  /* XXX */
             DEBUGMSGTL(( "mibII/udpScalar", "oid: "));
             DEBUGMSGOID(("mibII/udpScalar", requestvb->name,
                                             requestvb->name_length));
             DEBUGMSG((   "mibII/udpScalar", "\n"));

             switch (subid) {
 #ifdef USES_SNMP_DESIGNED_UDPSTAT
     case UDPINDATAGRAMS:
         ret_value = udpstat.udpInDatagrams;
         break;
     case UDPNOPORTS:
 #ifdef solaris2
         ret_value = udp_load(NULL, (void *)UDPNOPORTS);
 	if (ret_value == -1) {
             netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
             continue;
 	}
         break;
 #else
         ret_value = udpstat.udpNoPorts;
         break;
 #endif
     case UDPOUTDATAGRAMS:
         ret_value = udpstat.udpOutDatagrams;
         break;
     case UDPINERRORS:
         ret_value = udpstat.udpInErrors;
         break;
 #elif defined(USES_TRADITIONAL_UDPSTAT) && !defined(_USE_PERFSTAT_PROTOCOL)
 #ifdef HAVE_SYS_TCPIPSTATS_H
     /*
      * This actually reads statistics for *all* the groups together,
      * so we need to isolate the UDP-specific bits.
      */
 #define udpstat          udpstat.udpstat
 #endif
     case UDPINDATAGRAMS:
 #if HAVE_STRUCT_UDPSTAT_UDPS_IPACKETS
         ret_value = udpstat.udps_ipackets;
         break;
 #else
         netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
         continue;
 #endif

     case UDPNOPORTS:
 #if HAVE_STRUCT_UDPSTAT_UDPS_NOPORT
         ret_value = udpstat.udps_noport;
         break;
 #else
         netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
         continue;
 #endif

     case UDPOUTDATAGRAMS:
 #if HAVE_STRUCT_UDPSTAT_UDPS_OPACKETS
         ret_value = udpstat.udps_opackets;
         break;
 #else
         netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
         continue;
 #endif

     case UDPINERRORS:
         ret_value = udpstat.udps_hdrops + udpstat.udps_badsum +
 #ifdef HAVE_STRUCT_UDPSTAT_UDPS_DISCARD
             udpstat.udps_discard +
 #endif
 #ifdef HAVE_STRUCT_UDPSTAT_UDPS_FULLSOCK
             udpstat.udps_fullsock +
 #endif
             udpstat.udps_badlen;
         break;
 #ifdef HAVE_SYS_TCPIPSTATS_H
 #undef udpstat
 #endif
 #elif defined(hpux11)
     case UDPINDATAGRAMS:
     case UDPNOPORTS:
     case UDPOUTDATAGRAMS:
     case UDPINERRORS:
 	/*
 	 * This is a bit of a hack, to shoehorn the HP-UX 11
 	 * single-object retrieval approach into the caching
 	 * architecture.
 	 */
 	if (udp_load(NULL, (void*)subid) == -1 ) {
             netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
             continue;
 	}
         ret_value = udpstat;
         break;
 #elif defined(WIN32)
     case UDPINDATAGRAMS:
         ret_value = udpstat.dwInDatagrams;
         break;
     case UDPNOPORTS:
         ret_value = udpstat.dwNoPorts;
         break;
     case UDPOUTDATAGRAMS:
         ret_value = udpstat.dwOutDatagrams;
         break;
     case UDPINERRORS:
         ret_value = udpstat.dwInErrors;
         break;
 #elif defined(_USE_PERFSTAT_PROTOCOL)
     case UDPINDATAGRAMS:
         ret_value = ps_proto.u.udp.ipackets;
         break;
     case UDPNOPORTS:
         ret_value = ps_proto.u.udp.no_socket;
         break;
     case UDPOUTDATAGRAMS:
         ret_value = ps_proto.u.udp.opackets;
         break;
     case UDPINERRORS:
         ret_value = ps_proto.u.udp.ierrors;
         break;
 #endif			/* USES_SNMP_DESIGNED_UDPSTAT */

 	    }
 	    snmp_set_var_typed_value(request->requestvb, (u_char)type,
 			             (u_char *)&ret_value, sizeof(ret_value));
 	}
         break;

     case MODE_GETNEXT:
     case MODE_GETBULK:
 #ifndef NETSNMP_NO_WRITE_SUPPORT
     case MODE_SET_RESERVE1:
     case MODE_SET_RESERVE2:
     case MODE_SET_ACTION:
     case MODE_SET_COMMIT:
     case MODE_SET_FREE:
     case MODE_SET_UNDO:
         snmp_log(LOG_WARNING, "mibII/udp: Unsupported mode (%d)\n",
                                reqinfo->mode);
         break;
 #endif /* !NETSNMP_NO_WRITE_SUPPORT */
     default:
         snmp_log(LOG_WARNING, "mibII/udp: Unrecognised mode (%d)\n",
                                reqinfo->mode);
         break;
     }

     return SNMP_ERR_NOERROR;
 }


         /*********************
 	 *
 	 *  Internal implementation functions
 	 *
 	 *********************/

 #ifdef hpux11
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     int             fd;
     struct nmparms  p;
     unsigned int    ulen;
     int             ret;
     int             magic = (int) vmagic;

     if ((fd = open_mib("/dev/ip", O_RDONLY, 0, NM_ASYNC_OFF)) < 0) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP object %d (hpux11)\n", magic));
         return (-1);            /* error */
     }

     switch (magic) {
     case UDPINDATAGRAMS:
         p.objid = ID_udpInDatagrams;
         break;
     case UDPNOPORTS:
         p.objid = ID_udpNoPorts;
         break;
     case UDPOUTDATAGRAMS:
         p.objid = ID_udpOutDatagrams;
         break;
     case UDPINERRORS:
         p.objid = ID_udpInErrors;
         break;
     default:
         udpstat = 0;
         close_mib(fd);
         return -1;
     }

     p.buffer = (void *)&udpstat;
     ulen = sizeof(UDP_STAT_STRUCTURE);
     p.len = &ulen;
     ret = get_mib_info(fd, &p);
     close_mib(fd);

     DEBUGMSGTL(("mibII/udpScalar", "%s UDP object %d (hpux11)\n",
                (ret < 0 ? "Failed to load" : "Loaded"),  magic));
     return (ret);         /* 0: ok, < 0: error */
 }
 #elif defined(linux)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     ret_value = linux_read_udp_stat(&udpstat);

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (linux)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (linux)\n"));
     }
     return ret_value;
 }
 #elif defined(solaris2)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;
     int  magic = (int)vmagic;
     mib2_ip_t ipstat;

     /*
      * udpNoPorts is actually implemented as part of the MIB_IP group
      * so we need to retrieve this independently
      */
     if (magic == UDPNOPORTS) {
         if (getMibstat
             (MIB_IP, &ipstat, sizeof(mib2_ip_t), GET_FIRST,
              &Get_everything, NULL) < 0) {
             DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP object %d (solaris)\n", magic));
             return -1;
         } else {
             DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP object %d (solaris)\n", magic));
             return ipstat.udpNoPorts;
         }
     }

     /*
      * Otherwise, retrieve the whole of the MIB_UDP group (and cache it)
      */
     ret_value = getMibstat(MIB_UDP, &udpstat, sizeof(mib2_udp_t),
                            GET_FIRST, &Get_everything, NULL);

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (solaris)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (solaris)\n"));
     }
     return ret_value;
 }
 #elif defined(NETBSD_STATS_VIA_SYSCTL)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     ret_value = netbsd_read_udp_stat(&udpstat);

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (netbsd)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (netbsd)\n"));
     }
     return ret_value;
 }
 #elif defined(WIN32)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     ret_value = GetUdpStatistics(&udpstat);

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (win32)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (win32)\n"));
     }
     return ret_value;
 }
 #elif defined(_USE_PERFSTAT_PROTOCOL)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     strcpy(ps_name.name, "udp");
     ret_value = perfstat_protocol(&ps_name, &ps_proto, sizeof(ps_proto), 1);

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (AIX)\n"));
     } else {
         ret_value = 0;
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (AIX)\n"));
     }
     return ret_value;
 }
 #elif (defined(NETSNMP_CAN_USE_SYSCTL) && defined(UDPCTL_STATS))
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     int     sname[4]  = { CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_STATS };
     size_t  len       = sizeof(udpstat);
     long    ret_value = -1;

     ret_value = sysctl(sname, 4, &udpstat, &len, 0, 0);

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (sysctl)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (sysctl)\n"));
     }
     return ret_value;
 }
 #elif defined(HAVE_SYS_TCPIPSTATS_H)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     ret_value = sysmp(MP_SAGET, MPSA_TCPIPSTATS, &udpstat, sizeof(udpstat));

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (tcpipstats)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (tcpipstats)\n"));
     }
     return ret_value;
 }
 #elif defined(UDPSTAT_SYMBOL)
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     if (auto_nlist(UDPSTAT_SYMBOL, (char *)&udpstat, sizeof(udpstat)))
         ret_value = 0;

     if ( ret_value < 0 ) {
         DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (udpstat)\n"));
     } else {
         DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (udpstat)\n"));
     }
     return ret_value;
 }
 #else				/* UDPSTAT_SYMBOL */
 int
 udp_load(netsnmp_cache *cache, void *vmagic)
 {
     long ret_value = -1;

     DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (null)\n"));
     return ret_value;
 }
 #endif                          /* hpux11 */


 void
 udp_free(netsnmp_cache *cache, void *magic)
 {
 #if defined(_USE_PERFSTAT_PROTOCOL)
     memset(&ps_proto, 0, sizeof(ps_proto));
 #else
     memset(&udpstat, 0, sizeof(udpstat));
 #endif
 }
	/*
	* UDP MIB group implementation - udp.c
	*
	*/

	#include <net-snmp/net-snmp-config.h>
	#include "mibII_common.h"

	#ifdef HAVE_NETINET_UDP_H
	#include <netinet/udp.h>
	#endif
	#if HAVE_NETINET_UDP_VAR_H
	#include <netinet/udp_var.h>
	#endif

	#include <net-snmp/net-snmp-includes.h>
	#include <net-snmp/agent/net-snmp-agent-includes.h>
	#include <net-snmp/agent/auto_nlist.h>
	#include <net-snmp/agent/sysORTable.h>

	#include "util_funcs/MIB_STATS_CACHE_TIMEOUT.h"

	#ifdef linux
	#include "tcp.h"
	#endif
	#include "udp.h"
	#include "udpTable.h"

	#ifdef NETSNMP_CAN_USE_SYSCTL
	#include <sys/sysctl.h>
	#endif

	#ifndef MIB_STATS_CACHE_TIMEOUT
	#define MIB_STATS_CACHE_TIMEOUT 5
	#endif
	#ifndef UDP_STATS_CACHE_TIMEOUT
	#define UDP_STATS_CACHE_TIMEOUT MIB_STATS_CACHE_TIMEOUT
	#endif

	#if defined(HAVE_LIBPERFSTAT_H) && (defined(aix4) \|\| defined(aix5) \|\| defined(aix6) \|\| defined(aix7)) && !defined(FIRST_PROTOCOL)
	#ifdef HAVE_SYS_PROTOSW_H
	#include <sys/protosw.h>
	#endif
	#include <libperfstat.h>
	#ifdef FIRST_PROTOCOL
	perfstat_protocol_t ps_proto;
	perfstat_id_t ps_name;
	#define _USE_PERFSTAT_PROTOCOL 1
	#endif
	#endif

	/*********************
	*
	* Kernel & interface information,
	* and internal forward declarations
	*
	*********************/


	/*********************
	*
	* Initialisation & common implementation functions
	*
	*********************/

	/*
	* Define the OID pointer to the top of the mib tree that we're
	* registering underneath, and the OID for the MIB module
	*/
	oid udp_oid[] = { SNMP_OID_MIB2, 7 };
	oid udp_module_oid[] = { SNMP_OID_MIB2, 50 };

	void
	init_udp(void)
	{
	netsnmp_handler_registration *reginfo;
	int rc;

	/*
	* register ourselves with the agent as a group of scalars...
	*/
	DEBUGMSGTL(("mibII/udpScalar", "Initialising UDP scalar group\n"));
	reginfo = netsnmp_create_handler_registration("udp", udp_handler,
	udp_oid, OID_LENGTH(udp_oid), HANDLER_CAN_RONLY);
	rc = netsnmp_register_scalar_group(reginfo, UDPINDATAGRAMS, UDPOUTDATAGRAMS);
	if (rc != SNMPERR_SUCCESS)
	return;

	/*
	* .... with a local cache
	* (except for HP-UX 11, which extracts objects individually)
	*/
	#ifndef hpux11
	netsnmp_inject_handler( reginfo,
	netsnmp_get_cache_handler(UDP_STATS_CACHE_TIMEOUT,
	udp_load, udp_free,
	udp_oid, OID_LENGTH(udp_oid)));
	#endif

	REGISTER_SYSOR_ENTRY(udp_module_oid,
	"The MIB module for managing UDP implementations");

	#if !defined(_USE_PERFSTAT_PROTOCOL)
	#ifdef UDPSTAT_SYMBOL
	auto_nlist(UDPSTAT_SYMBOL, 0, 0);
	#endif
	#ifdef UDB_SYMBOL
	auto_nlist(UDB_SYMBOL, 0, 0);
	#endif
	#ifdef solaris2
	init_kernel_sunos5();
	#endif
	#endif
	}


	/*********************
	*
	* System specific implementation functions
	*
	*********************/

	#ifdef hpux11
	#define UDP_STAT_STRUCTURE int
	#endif

	#ifdef linux
	#define UDP_STAT_STRUCTURE struct udp_mib
	#define USES_SNMP_DESIGNED_UDPSTAT
	#undef UDPSTAT_SYMBOL
	#endif

	#ifdef solaris2
	#define UDP_STAT_STRUCTURE mib2_udp_t
	#define USES_SNMP_DESIGNED_UDPSTAT
	#endif

	#ifdef NETBSD_STATS_VIA_SYSCTL
	#define UDP_STAT_STRUCTURE struct udp_mib
	#define USES_SNMP_DESIGNED_UDPSTAT
	#undef UDP_NSTATS
	#endif

	#ifdef HAVE_IPHLPAPI_H
	#include <iphlpapi.h>
	#define UDP_STAT_STRUCTURE MIB_UDPSTATS
	#endif

	#ifdef HAVE_SYS_TCPIPSTATS_H
	#define UDP_STAT_STRUCTURE struct kna
	#define USES_TRADITIONAL_UDPSTAT
	#endif


	#if !defined(UDP_STAT_STRUCTURE)
	#define UDP_STAT_STRUCTURE struct udpstat
	#define USES_TRADITIONAL_UDPSTAT
	#endif

	UDP_STAT_STRUCTURE udpstat;


	/*********************
	*
	* System independent handler (mostly)
	*
	*********************/



	int
	udp_handler(netsnmp_mib_handler *handler,
	netsnmp_handler_registration *reginfo,
	netsnmp_agent_request_info *reqinfo,
	netsnmp_request_info *requests)
	{
	netsnmp_request_info *request;
	netsnmp_variable_list *requestvb;
	long ret_value = -1;
	oid subid;
	int type = ASN_COUNTER;

	/*
	* The cached data should already have been loaded by the
	* cache handler, higher up the handler chain.
	* But just to be safe, check this and load it manually if necessary
	*/
	#if defined(_USE_PERFSTAT_PROTOCOL)
	udp_load(NULL, NULL);
	#endif


	/*
	*
	*
	*/
	DEBUGMSGTL(("mibII/udpScalar", "Handler - mode %s\n",
	se_find_label_in_slist("agent_mode", reqinfo->mode)));
	switch (reqinfo->mode) {
	case MODE_GET:
	for (request=requests; request; request=request->next) {
	requestvb = request->requestvb;
	subid = requestvb->name[OID_LENGTH(udp_oid)]; /* XXX */
	DEBUGMSGTL(( "mibII/udpScalar", "oid: "));
	DEBUGMSGOID(("mibII/udpScalar", requestvb->name,
	requestvb->name_length));
	DEBUGMSG(( "mibII/udpScalar", "\n"));

	switch (subid) {
	#ifdef USES_SNMP_DESIGNED_UDPSTAT
	case UDPINDATAGRAMS:
	ret_value = udpstat.udpInDatagrams;
	break;
	case UDPNOPORTS:
	#ifdef solaris2
	ret_value = udp_load(NULL, (void *)UDPNOPORTS);
	if (ret_value == -1) {
	netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
	continue;
	}
	break;
	#else
	ret_value = udpstat.udpNoPorts;
	break;
	#endif
	case UDPOUTDATAGRAMS:
	ret_value = udpstat.udpOutDatagrams;
	break;
	case UDPINERRORS:
	ret_value = udpstat.udpInErrors;
	break;
	#elif defined(USES_TRADITIONAL_UDPSTAT) && !defined(_USE_PERFSTAT_PROTOCOL)
	#ifdef HAVE_SYS_TCPIPSTATS_H
	/*
	* This actually reads statistics for all the groups together,
	* so we need to isolate the UDP-specific bits.
	*/
	#define udpstat udpstat.udpstat
	#endif
	case UDPINDATAGRAMS:
	#if HAVE_STRUCT_UDPSTAT_UDPS_IPACKETS
	ret_value = udpstat.udps_ipackets;
	break;
	#else
	netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
	continue;
	#endif

	case UDPNOPORTS:
	#if HAVE_STRUCT_UDPSTAT_UDPS_NOPORT
	ret_value = udpstat.udps_noport;
	break;
	#else
	netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
	continue;
	#endif

	case UDPOUTDATAGRAMS:
	#if HAVE_STRUCT_UDPSTAT_UDPS_OPACKETS
	ret_value = udpstat.udps_opackets;
	break;
	#else
	netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
	continue;
	#endif

	case UDPINERRORS:
	ret_value = udpstat.udps_hdrops + udpstat.udps_badsum +
	#ifdef HAVE_STRUCT_UDPSTAT_UDPS_DISCARD
	udpstat.udps_discard +
	#endif
	#ifdef HAVE_STRUCT_UDPSTAT_UDPS_FULLSOCK
	udpstat.udps_fullsock +
	#endif
	udpstat.udps_badlen;
	break;
	#ifdef HAVE_SYS_TCPIPSTATS_H
	#undef udpstat
	#endif
	#elif defined(hpux11)
	case UDPINDATAGRAMS:
	case UDPNOPORTS:
	case UDPOUTDATAGRAMS:
	case UDPINERRORS:
	/*
	* This is a bit of a hack, to shoehorn the HP-UX 11
	* single-object retrieval approach into the caching
	* architecture.
	*/
	if (udp_load(NULL, (void*)subid) == -1 ) {
	netsnmp_set_request_error(reqinfo, request, SNMP_NOSUCHOBJECT);
	continue;
	}
	ret_value = udpstat;
	break;
	#elif defined(WIN32)
	case UDPINDATAGRAMS:
	ret_value = udpstat.dwInDatagrams;
	break;
	case UDPNOPORTS:
	ret_value = udpstat.dwNoPorts;
	break;
	case UDPOUTDATAGRAMS:
	ret_value = udpstat.dwOutDatagrams;
	break;
	case UDPINERRORS:
	ret_value = udpstat.dwInErrors;
	break;
	#elif defined(_USE_PERFSTAT_PROTOCOL)
	case UDPINDATAGRAMS:
	ret_value = ps_proto.u.udp.ipackets;
	break;
	case UDPNOPORTS:
	ret_value = ps_proto.u.udp.no_socket;
	break;
	case UDPOUTDATAGRAMS:
	ret_value = ps_proto.u.udp.opackets;
	break;
	case UDPINERRORS:
	ret_value = ps_proto.u.udp.ierrors;
	break;
	#endif /* USES_SNMP_DESIGNED_UDPSTAT */

	}
	snmp_set_var_typed_value(request->requestvb, (u_char)type,
	(u_char *)&ret_value, sizeof(ret_value));
	}
	break;

	case MODE_GETNEXT:
	case MODE_GETBULK:
	#ifndef NETSNMP_NO_WRITE_SUPPORT
	case MODE_SET_RESERVE1:
	case MODE_SET_RESERVE2:
	case MODE_SET_ACTION:
	case MODE_SET_COMMIT:
	case MODE_SET_FREE:
	case MODE_SET_UNDO:
	snmp_log(LOG_WARNING, "mibII/udp: Unsupported mode (%d)\n",
	reqinfo->mode);
	break;
	#endif /* !NETSNMP_NO_WRITE_SUPPORT */
	default:
	snmp_log(LOG_WARNING, "mibII/udp: Unrecognised mode (%d)\n",
	reqinfo->mode);
	break;
	}

	return SNMP_ERR_NOERROR;
	}


	/*********************
	*
	* Internal implementation functions
	*
	*********************/

	#ifdef hpux11
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	int fd;
	struct nmparms p;
	unsigned int ulen;
	int ret;
	int magic = (int) vmagic;

	if ((fd = open_mib("/dev/ip", O_RDONLY, 0, NM_ASYNC_OFF)) < 0) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP object %d (hpux11)\n", magic));
	return (-1); /* error */
	}

	switch (magic) {
	case UDPINDATAGRAMS:
	p.objid = ID_udpInDatagrams;
	break;
	case UDPNOPORTS:
	p.objid = ID_udpNoPorts;
	break;
	case UDPOUTDATAGRAMS:
	p.objid = ID_udpOutDatagrams;
	break;
	case UDPINERRORS:
	p.objid = ID_udpInErrors;
	break;
	default:
	udpstat = 0;
	close_mib(fd);
	return -1;
	}

	p.buffer = (void *)&udpstat;
	ulen = sizeof(UDP_STAT_STRUCTURE);
	p.len = &ulen;
	ret = get_mib_info(fd, &p);
	close_mib(fd);

	DEBUGMSGTL(("mibII/udpScalar", "%s UDP object %d (hpux11)\n",
	(ret < 0 ? "Failed to load" : "Loaded"), magic));
	return (ret); /* 0: ok, < 0: error */
	}
	#elif defined(linux)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	ret_value = linux_read_udp_stat(&udpstat);

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (linux)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (linux)\n"));
	}
	return ret_value;
	}
	#elif defined(solaris2)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;
	int magic = (int)vmagic;
	mib2_ip_t ipstat;

	/*
	* udpNoPorts is actually implemented as part of the MIB_IP group
	* so we need to retrieve this independently
	*/
	if (magic == UDPNOPORTS) {
	if (getMibstat
	(MIB_IP, &ipstat, sizeof(mib2_ip_t), GET_FIRST,
	&Get_everything, NULL) < 0) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP object %d (solaris)\n", magic));
	return -1;
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP object %d (solaris)\n", magic));
	return ipstat.udpNoPorts;
	}
	}

	/*
	* Otherwise, retrieve the whole of the MIB_UDP group (and cache it)
	*/
	ret_value = getMibstat(MIB_UDP, &udpstat, sizeof(mib2_udp_t),
	GET_FIRST, &Get_everything, NULL);

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (solaris)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (solaris)\n"));
	}
	return ret_value;
	}
	#elif defined(NETBSD_STATS_VIA_SYSCTL)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	ret_value = netbsd_read_udp_stat(&udpstat);

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (netbsd)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (netbsd)\n"));
	}
	return ret_value;
	}
	#elif defined(WIN32)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	ret_value = GetUdpStatistics(&udpstat);

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (win32)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (win32)\n"));
	}
	return ret_value;
	}
	#elif defined(_USE_PERFSTAT_PROTOCOL)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	strcpy(ps_name.name, "udp");
	ret_value = perfstat_protocol(&ps_name, &ps_proto, sizeof(ps_proto), 1);

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (AIX)\n"));
	} else {
	ret_value = 0;
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (AIX)\n"));
	}
	return ret_value;
	}
	#elif (defined(NETSNMP_CAN_USE_SYSCTL) && defined(UDPCTL_STATS))
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	int sname[4] = { CTL_NET, PF_INET, IPPROTO_UDP, UDPCTL_STATS };
	size_t len = sizeof(udpstat);
	long ret_value = -1;

	ret_value = sysctl(sname, 4, &udpstat, &len, 0, 0);

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (sysctl)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (sysctl)\n"));
	}
	return ret_value;
	}
	#elif defined(HAVE_SYS_TCPIPSTATS_H)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	ret_value = sysmp(MP_SAGET, MPSA_TCPIPSTATS, &udpstat, sizeof(udpstat));

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (tcpipstats)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (tcpipstats)\n"));
	}
	return ret_value;
	}
	#elif defined(UDPSTAT_SYMBOL)
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	if (auto_nlist(UDPSTAT_SYMBOL, (char *)&udpstat, sizeof(udpstat)))
	ret_value = 0;

	if ( ret_value < 0 ) {
	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (udpstat)\n"));
	} else {
	DEBUGMSGTL(("mibII/udpScalar", "Loaded UDP scalar Group (udpstat)\n"));
	}
	return ret_value;
	}
	#else /* UDPSTAT_SYMBOL */
	int
	udp_load(netsnmp_cache cache, void vmagic)
	{
	long ret_value = -1;

	DEBUGMSGTL(("mibII/udpScalar", "Failed to load UDP scalar Group (null)\n"));
	return ret_value;
	}
	#endif /* hpux11 */


	void
	udp_free(netsnmp_cache cache, void magic)
	{
	#if defined(_USE_PERFSTAT_PROTOCOL)
	memset(&ps_proto, 0, sizeof(ps_proto));
	#else
	memset(&udpstat, 0, sizeof(udpstat));
	#endif
	}