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/*
* gennt.c v0.14 May 15, 1996 * **************************************************************************** * * * (C) Copyright 1995 DIGITAL EQUIPMENT CORPORATION * * * * This software is an unpublished work protected under the * * the copyright laws of the United States of America, all * * rights reserved. * * * * In the event this software is licensed for use by the United * * States Government, all use, duplication or disclosure by the * * United States Government is subject to restrictions as set * * forth in either subparagraph (c)(1)(ii) of the Rights in * * Technical Data And Computer Software Clause at DFARS * * 252.227-7013, or the Commercial Computer Software Restricted * * Rights Clause at FAR 52.221-19, whichever is applicable. * * * **************************************************************************** * * Facility: * * SNMP Extension Agent * * Abstract: * * This module contains the code for dealing with the generic logic for * processing the SNMP request. It is table driven. No user modification * should be done. * * Functions: * * ResolveVarBind() * FindClass() * ResolveGetNext() * * Author: * Miriam Amos Nihart, Kathy Faust * * Date: * 2/17/95 * * Revision History: * 6/22/95 krw0001 FindClass - modify to stop checking for valid variable - we only care about valid * class. * Rewrite ResolveGetNext * 6/26/95 ags FindClass - stop checking for valid variable * Rewrite ResolveGetNext * 7/31/95 ags SNMP_oidfree works with CRTDLL.lib, hence use them. * 2/14/96 ags v0.11 one fix for the getnext bug found by Cindy * 3/19/96 kff v0.12 modified for trap support * 4/19/96 ags v0.13 Modified to get rid of trap.c in case of no traps. * 5/15/96 cs v0.14 Modified FindClass in the backward walkthru to tighten * up the verification */
#include <windows.h>
#include <malloc.h>
#include <stdio.h>
#include <snmp.h>
#include "mib.h"
#include "mib_xtrn.h"
#include "smint.h"
extern DWORD dwTimeZero ;
UINTSnmpUtilOidMatch(AsnObjectIdentifier *pOid1, AsnObjectIdentifier *pOid2){ unsigned long int nScan = min(pOid1->idLength, pOid2->idLength); unsigned long int i;
for (i = 0; i < nScan; i++) { if (pOid1->ids[i] != pOid2->ids[i]) break; }
return i;}
/*
* ResolveVarBind * * Resolves a single variable binding. Modifies the variable value pair * on a GET or a GET-NEXT. * * Arguments: * * VarBind pointer to the variable value pair * PduAction type of request - get, set, or getnext * * Return Codes: * * Standard PDU error codes. * */
UINTResolveVarBind( IN OUT RFC1157VarBind *VarBind , // Variable Binding to resolve
IN UINT PduAction ) // Action specified in PDU
{ unsigned long int cindex ; // index into the class info table
unsigned long int vindex ; // index into the class's var table
UINT instance_array[ MAX_STRING_LEN ] ; UINT status ; UINT result ; // SNMP PDU error status
AsnObjectIdentifier instance ; InstanceName native_instance ;
instance.ids = instance_array ;
// Determine which class the VarBind is for
status = FindClass( VarBind, &cindex ) ; if ( status ) { if ( PduAction != MIB_ACTION_GETNEXT ) { // Check for valid variable as this is a get or set
CHECK_VARIABLE( VarBind, cindex, vindex, status ) ; if ( !status ) return SNMP_ERRORSTATUS_NOSUCHNAME ;
// Check for valid instance
status = ( *class_info[ cindex ].FindInstance ) ( (ObjectIdentifier *)&(VarBind->name) , (ObjectIdentifier *)&instance ) ; if ( status != SNMP_ERRORSTATUS_NOERROR ) return status ;
// Check for access
CHECK_ACCESS( cindex, vindex, PduAction, status ) ; if ( !status ) { if ( PduAction == MIB_ACTION_SET ) return SNMP_ERRORSTATUS_NOTWRITABLE ; else return SNMP_ERRORSTATUS_GENERR ; }
// Ok to do the get or set
if ( PduAction == MIB_ACTION_GET ) { status = ( *class_info[ cindex ].ConvertInstance ) ( (ObjectIdentifier *)&instance, &native_instance ) ; if ( status == FAILURE ) return SNMP_ERRORSTATUS_GENERR ;
result = ( *class_info[ cindex ].variable[ vindex].SMIGet ) ( VarBind , cindex, vindex, &native_instance ) ; } else { if ( VarBind->value.asnType != class_info[ cindex ].variable[ vindex ].type ) return SNMP_ERRORSTATUS_BADVALUE ;
status = ( *class_info[ cindex ].ConvertInstance ) ( (ObjectIdentifier *)&instance, &native_instance ) ; if ( status == FAILURE ) return SNMP_ERRORSTATUS_GENERR ;
result = ( *class_info[ cindex ].variable[ vindex ].SMISet ) ( VarBind, cindex, vindex, &native_instance ) ; } } else // This is a GETNEXT
{ //
// Call ResolveGetNext() to determine which class, variable, and
// instance to do a Get on.
//
status = ResolveGetNext( VarBind, &cindex, &vindex, &instance ) ; if ( status == SUCCESS ) { status = ( *class_info[ cindex ].ConvertInstance ) ( (ObjectIdentifier *)&instance, &native_instance ) ; if ( status == FAILURE ) return SNMP_ERRORSTATUS_GENERR ;
result = ( *class_info[ cindex ].variable[ vindex ].SMIGet ) ( VarBind, cindex, vindex, &native_instance ) ; } else return SNMP_ERRORSTATUS_NOSUCHNAME ; }
} else { //
// No class found, but its a GETNEXT.. we need to find the class that has the longest
// with the requested oid and forward the request to it
//
if (PduAction == MIB_ACTION_GETNEXT) { unsigned long int ci; // index into the class info table
unsigned long int nLongestMatch; // max number of ids that matched between names
unsigned long int nCurrentMatch; // matching number of IDs at the current iteration
// scan the class_info table, relying on the fact that the table is ordered
// ordered ascendingly on the class OID.
for (ci = 0, nLongestMatch = 0; ci < CLASS_TABLE_MAX; ci++) { // pick up the number of matching ids between the VarBind and the class name..
nCurrentMatch = SnmpUtilOidMatch(&VarBind->name, class_info[ci].oid);
// store in cindex the first class with the highest match number
if (nCurrentMatch > nLongestMatch) { cindex = ci; nLongestMatch = nCurrentMatch; } }
// only if VarBind name is longer than the match number we need to look
// for an even better match
if (VarBind->name.idLength > nLongestMatch) { for (;cindex < CLASS_TABLE_MAX; cindex++) { // make sure we don't go over the range with the longest Match
if (SnmpUtilOidMatch(&VarBind->name, class_info[cindex].oid) != nLongestMatch) break;
// if the class matches entirely into the VarBind name, check if the first ID
// that follows in VarBind name is inside the range supported by the class
if (class_info[cindex].oid->idLength == nLongestMatch) { // this is a hack - we rely the var_index is always 1 more than number of ids in
// the class_info name. Since VarBind has already a name longer than nLongestMatch
// no buffer overrun happens here.
// if the VarBind name is in the right range, then we found the class - just break the loop
// (don't forget, var_index is '1' based)
if(VarBind->name.ids[class_info[cindex].var_index - 1] <= class_info[cindex].max_index) break; } else { // the VarBind name is longer than the IDs that match, the class_info name is the same
// the first ID that follows in both names can't be equal, so we can break the loop if
// the VarBind name is just in front of it.
if (VarBind->name.ids[nLongestMatch] < class_info[cindex].oid->ids[nLongestMatch]) break; }
} }
if (cindex < CLASS_TABLE_MAX ) vindex = class_info[cindex].min_index ; else return SNMP_ERRORSTATUS_NOSUCHNAME ;
SNMP_oidfree( &VarBind->name ) ; if (! SNMP_oidcpy( &VarBind->name , class_info[ cindex ].variable[ vindex ].oid ) ) { return SNMP_ERRORSTATUS_GENERR ; } status = ResolveGetNext( VarBind, &cindex, &vindex, &instance ) ; if ( status == SUCCESS ) { status = ( *class_info[ cindex ].ConvertInstance ) ( (ObjectIdentifier *)&instance, &native_instance ) ; if ( status == FAILURE ) return SNMP_ERRORSTATUS_GENERR ;
result = ( *class_info[ cindex ].variable[ vindex ].SMIGet ) ( VarBind, cindex, vindex, &native_instance ) ; } else { return SNMP_ERRORSTATUS_NOSUCHNAME ; } } else return SNMP_ERRORSTATUS_NOSUCHNAME ; }
( *class_info[ cindex ].FreeInstance )( &native_instance ) ; return result ;
} /* end of ResolveVarBind() */
/*
* FindClass * * This routine determines the class by walking the class_info table * backwards and comparing the class oids. The table is walked * backwards because it assumes that the classes are listed in * increasing order. For example, * * Group Name Group Identifier * * group1 1.3.6.1.4.1.36.2.78 * table1 1.3.6.1.4.1.36.2.78.9 * table2 1.3.6.1.4.1.36.2.78.10 * * We need to look for the longest exact match on the oid thus we * walk the table backwards. * * Arguments: * * VarBind Variable value pair * class Index into the class_info * * Return Codes: * * SUCCESS Class is valid, return index into class_info * FAILURE Invalid class * */
UINTFindClass( IN RFC1157VarBind *VarBind , IN OUT UINT *cindex ){ int index ; UINT status, vindex ; UINT length ;
for ( index = CLASS_TABLE_MAX - 1 ; index >= 0 ; index-- ) { if ( class_info[ index ].table ) // skip over the entry code -- kkf, why?
// length = class_info[ index ].var_index - 2 ;
length = class_info[ index ].var_index - 1 ; else length = class_info[ index ].var_index - 1 ; status = SNMP_oidncmp( &VarBind->name , class_info[ index ].oid , length ) ;
// if the oid don't match the class or it is shorter than the
// class go on to the next one.
// If the oid requested is shorter than the class we can't stop
// otherwise we'll point to a wrong (longest match) class.
if (status != 0 || VarBind->name.idLength < class_info[ index ].var_index) continue;
vindex = VarBind->name.ids[ class_info[ index ].var_index - 1 ] ; // cs - added the vindex verification to make sure that the varbind
// oid definitely belongs in this class (fixed partial table oids)
if ( vindex >= class_info[ index ].min_index && vindex <= class_info[ index ].max_index) { *cindex = index ; return SUCCESS ; } }
// Failed to match by walking list backwards (longest match)
// so OID supplied is shorter than expected (e.g., partial OID supplied)
// Try matching by forward walking...
for (index = 0; index < CLASS_TABLE_MAX; index++ ) { status = SNMP_oidncmp( &VarBind->name , class_info[ index ].oid , VarBind->name.idLength ) ; if ( status == 0 ) { *cindex = index ; return SUCCESS ; } }
return FAILURE ;
} /* end of FindClass() */
/*
* ResolveGetNext * * Determines the class, the variable and the instance that the * GetNext request is to be performed on. This is a recursive * routine. The input arguments VarBind and class may be modified * as part of the resolution. * * The rules for getnext are: * 1. No instance and no variable specified so return the first * variable for the first instance. * 2. No instance specified but a variable is specified so return * the variable for the first instance. * 3. An instance and a variable are specified * Follow 3a,4b for Non Tables * Follow 3b, 4b, 5b for Tables * * 3a.Return the next variable for the instance. * 4a.An instance and a variable are specified but the variable is the * last variable in the group so return the first variable for the * next group. * If there is no next group return FAILURE. * * 3b. Return the variable for the next instance ( walk down the column). * 4b. Reached the bottom of the column, start at the top of next column. * 5b. An instance and a variable are specified but it is the last * variable and the last instace so roll to the next group (class). * If there is no next group return FAILURE. * * Arguments: * * VarBind Variable value pair * cindex Index into the class_info * vindex address to specify variable for the get * * Return Codes: * * SUCCESS Able to resolve the request to a class, variable * and instance * FAILURE Unable to resolve the request within this MIB * */
UINTResolveGetNext( IN OUT RFC1157VarBind *VarBind , IN OUT UINT *cindex , IN OUT UINT *vindex , OUT AsnObjectIdentifier *instance ) { UINT status ; access_mode_t tmpAccess ;
/*
* We've come in with a pointer to the class, to start with * Do we have a variable specified? */ *vindex = 0 ; if (VarBind->name.idLength < class_info[ *cindex ].var_index ) { /*
* No variable specified. so pick the first variable (if it exists) * to start the search for a valid variable. * If not roll over to the next class. * Instnace is 0 for non Tables, and the first instance for Tables. */
if ( class_info[ *cindex ].min_index <= class_info[ *cindex ].max_index) {
*vindex = class_info[ *cindex ].min_index ; goto StartSearchAt; } else { goto BumpClass; }
} else { /*
* Yes, a variable is specified. * If it is below min_index, start testing for a valid variable at the min_index. * If it is ablove max_index roll over to the next class. * If we change the variable, Instance is reset to the first (or the only) Instance. */ *vindex = VarBind->name.ids[ class_info[ *cindex ].var_index - 1 ] ; if ( *vindex < class_info[ *cindex ].min_index) { *vindex = class_info[ *cindex ].min_index ; goto StartSearchAt; } if ( *vindex > class_info[ *cindex ].max_index) goto BumpClass; /*
* A valid variable for this class is specified. Table & NonTable are treated * differently. * In case of Non Tables: * if instance is specified, we start the serach for a valid variable at the * next variable. * if no instnace is specified, we start search at the specified variable. * * In case of Tables: * We may have * a. No Instance start at the 1st Instance * b. Partial instance start at the 1st Instance * c. Invalid instance start at the 1st Instance * d. Valid Instance start at the next Instance * All these cases will be handled by the FindNextInstance * Hence first check that access of the given vaiable, if it is readable * get the Next Instance. If not start the search for a valid variable at the next * variable. */
if ( class_info[ *cindex ].table == NON_TABLE ) { /* test for the Instance */ if ( VarBind->name.idLength > class_info[ *cindex ].var_index) (*vindex)++ ;
goto StartSearchAt; } else { /* Start Table case */ tmpAccess = class_info[ *cindex ].variable[ *vindex ].access_mode ; if ( ( tmpAccess == NSM_READ_ONLY ) || (tmpAccess == NSM_READ_WRITE) ) { /*
* readable Variable, walk down the column */ status = ( *class_info[ *cindex ].FindNextInstance ) ( (ObjectIdentifier *)&(VarBind->name) , (ObjectIdentifier *)instance ) ; if (status == SNMP_ERRORSTATUS_NOERROR) { SNMP_oidfree ( &VarBind->name ) ; if (! SNMP_oidcpy ( &VarBind->name, class_info[*cindex ].variable[*vindex].oid ) ) { return FAILURE; } if (!SNMP_oidappend ( &VarBind->name, instance )) { return FAILURE; } return SUCCESS ; /* we are all done */ } } /*
* Either at end of the column, or variable specified is non Readable. * Hence we need to move to the next column, * This means we start at the 1st instnace. */ (*vindex)++ ; goto StartSearchAt; /* End Table case */ } /* end of variable specified case */ }StartSearchAt: /*
* We have a start variable in *vindex. * At this point we are moving to the next column in case of a Table * Hence if we can't find an NextInstance ( empty Table), move to the * next class. */ status = FAILURE; while ( *vindex <= class_info[ *cindex ].max_index) {
tmpAccess = class_info[ *cindex ].variable[ *vindex ].access_mode ; if ( ( tmpAccess == NSM_READ_ONLY ) || (tmpAccess == NSM_READ_WRITE) ) { status = SUCCESS; break; } else { (*vindex)++; } }
if ( status == SUCCESS) { /*
* we hava a valid variable, get the instance */ SNMP_oidfree ( &VarBind->name ) ; if (!SNMP_oidcpy ( &VarBind->name, class_info[ *cindex ].variable[*vindex ].oid )) { return FAILURE; } if ( class_info[ *cindex ].table == NON_TABLE) { instance->ids[ 0 ] = 0 ; instance->idLength = 1 ; if (!SNMP_oidappend ( &VarBind->name, instance )) { return FAILURE; } return SUCCESS ;
} else {
status = ( *class_info[ *cindex ].FindNextInstance ) ( (ObjectIdentifier *)&(VarBind->name) , (ObjectIdentifier *)instance ) ; if (status == SNMP_ERRORSTATUS_NOERROR) { if (!SNMP_oidappend ( &VarBind->name, instance )) { return FAILURE; } return SUCCESS ; } } }
/*
* Come here to move on to the next class */
BumpClass: { (*cindex)++ ; if ( *cindex >= CLASS_TABLE_MAX) return FAILURE ; SNMP_oidfree( &VarBind->name ); if (!SNMP_oidcpy ( &VarBind->name, class_info[ *cindex ].oid )) { return FAILURE; } status = ResolveGetNext( VarBind, cindex, vindex, instance) ; return status ; } // This oughtn't to happen
return FAILURE ;} /* end of ResolveGetNext() */
#ifndef TRAPS
//
// If there are no traps, TrapInit() is still needed.
// If there are traps, all this code appears in
// generated file trap.c
//
UINT number_of_traps = 0 ;
trap_t trap_info[] = { { NULL, 0, 0, 0, NULL }} ;
externtrap_t trap_info[] ;
externUINT number_of_traps ;
extern HANDLE hEnabledTraps ;extern HANDLE hTrapQMutex ;
/*
* TrapInit * * This routine initializes the trap handle. * * Arguments: * * hPollForTrapEvent handle for traps - this is used to coordinate * between the Extendible Agent and this Extension * Agent. * - NULL indicates no traps * - value from CreateEvent() indicates traps * are implemented and the Extendible agent * must poll for them * * Return Code: * * SUCCESS Successful initialization * FAILURE Unable to initialize * |========================================================================= | There are no Traps associated with the HostMIB. Consequently this | routine is taken over and used to create a handle to a timer rather | than an event. | | We want to be entered at "SnmpExtensionTrap()" (in "HOSTMIB.C") on | a periodic interval. When entered, we won't really do any trap processing, | instead we'll refresh the cached information associated with SNMP | attribute "hrProcessorLoad" (in "HRPROCES.C") thru a call to function | "hrProcessLoad_Refresh()" (also in "HRPROCES.C"). | | So the contents of this standard function is replaced. (Note that the | "hTrapQMutex" is no longer created). */
VOIDTrapInit( IN OUT HANDLE *hPollForTrapEvent ){#if 0
// The default value for traps is NULL indicating NO traps.
*hPollForTrapEvent = NULL ; hTrapQMutex = NULL ;
// Call to CreateEvent uses the default security descriptor (therefore
// the handle is not inheritable), flags auto reset (no call to ResetEvent()
// required), flags no signal to be sent at the initial state, and does
// not specify a name for this event.
//
// If the CreateEvent() fails the value returned is NULL so traps
// are not enabled. Otherwise the setting of this event with will cause
// the Extendible Agent to call this Extension Agent's SnmpExtensionTrap
// routine to collect any traps.
*hPollForTrapEvent = CreateEvent( NULL , // Address of security attrib
FALSE , // Flag for manual-reset event
FALSE , // Flag for initial state
NULL ) ; // Address of event-object name
//
// Save the handle in a global variable for use later in setting a trap.
//
hEnabledTraps = *hPollForTrapEvent ;
//
// Create Mutex for assuring single thread access to enque/dequeue on trap_q
hTrapQMutex = CreateMutex( NULL, // Address of security attrib
FALSE, // Mutex is not initially owned
NULL ) ; // Mutex is unnamed
return ;#endif
/*
|========================| Special HostMIB code:*/LARGE_INTEGER due_time; /* When the timer first goes off */LONG period; /* Frequency: every minute */BOOL waitable; /* Status from SetWaitable() */
*hPollForTrapEvent = NULL ;
/* Attempt the creation of a waitable timer . . . */ *hPollForTrapEvent = CreateWaitableTimer(NULL, // Security
FALSE, // = Auto-resetting
NULL // = No name
);
/*
| Set a negative due time to mean "relative": We want it to go off | in 30 seconds. Ticks are 100 ns or 1/10th of a millionth of a second. | */ due_time.QuadPart = 10000000 * (-30);
/*
| Set the period in milliseconds to 1 minute. */ period = 1000 * 60;
/* If we actually managed to create it, start it */ if (*hPollForTrapEvent != NULL) {
waitable = SetWaitableTimer(*hPollForTrapEvent, // Handle to timer
&due_time, // "Due Time" to go off
period, // Length of period in ms.
NULL, // no completion routine
NULL, // no arg to comp. routine
FALSE // no power-resume in NT
); }
} /* end of TrapInit() */
#endif /* #ifndef TRAPS */
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