gosnmp

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// Copyright 2012 The GoSNMP Authors. All rights reserved.  Use of this
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// source code is governed by a BSD-style license that can be found in the
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// LICENSE file.
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package gosnmp
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import (
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	"fmt"
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	"strings"
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)
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func (x *GoSNMP) walk(getRequestType PDUType, rootOid string, walkFn WalkFunc) error {
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	if rootOid == "" || rootOid == "." {
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		rootOid = baseOid
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	}
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	if !strings.HasPrefix(rootOid, ".") {
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		rootOid = string(".") + rootOid
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	}
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	oid := rootOid
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	requests := 0
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	maxReps := x.MaxRepetitions
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	if maxReps == 0 {
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		maxReps = defaultMaxRepetitions
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	}
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	// AppOpt 'c: do not check returned OIDs are increasing'
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	checkIncreasing := true
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	if x.AppOpts != nil {
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		if _, ok := x.AppOpts["c"]; ok {
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			if getRequestType == GetBulkRequest || getRequestType == GetNextRequest {
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				checkIncreasing = false
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			}
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		}
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	}
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RequestLoop:
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	for {
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		requests++
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		var response *SnmpPacket
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		var err error
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		switch getRequestType {
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		case GetBulkRequest:
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			response, err = x.GetBulk([]string{oid}, uint8(x.NonRepeaters), maxReps)
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		case GetNextRequest:
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			response, err = x.GetNext([]string{oid})
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		case GetRequest:
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			response, err = x.Get([]string{oid})
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		default:
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			response, err = nil, fmt.Errorf("unsupported request type: %d", getRequestType)
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		}
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		if err != nil {
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			return err
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		}
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		if len(response.Variables) == 0 {
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			break RequestLoop
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		}
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		switch response.Error {
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		case TooBig:
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			x.Logger.Print("Walk terminated with TooBig")
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			break RequestLoop
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		case NoSuchName:
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			x.Logger.Print("Walk terminated with NoSuchName")
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			break RequestLoop
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		case BadValue:
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			x.Logger.Print("Walk terminated with BadValue")
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			break RequestLoop
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		case ReadOnly:
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			x.Logger.Print("Walk terminated with ReadOnly")
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			break RequestLoop
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		case GenErr:
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			x.Logger.Print("Walk terminated with GenErr")
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			break RequestLoop
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		case NoAccess:
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			x.Logger.Print("Walk terminated with NoAccess")
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			break RequestLoop
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		case WrongType:
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			x.Logger.Print("Walk terminated with WrongType")
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			break RequestLoop
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		case WrongLength:
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			x.Logger.Print("Walk terminated with WrongLength")
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			break RequestLoop
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		case WrongEncoding:
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			x.Logger.Print("Walk terminated with WrongEncoding")
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			break RequestLoop
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		case WrongValue:
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			x.Logger.Print("Walk terminated with WrongValue")
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			break RequestLoop
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		case NoCreation:
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			x.Logger.Print("Walk terminated with NoCreation")
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			break RequestLoop
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		case InconsistentValue:
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			x.Logger.Print("Walk terminated with InconsistentValue")
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			break RequestLoop
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		case ResourceUnavailable:
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			x.Logger.Print("Walk terminated with ResourceUnavailable")
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			break RequestLoop
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		case CommitFailed:
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			x.Logger.Print("Walk terminated with CommitFailed")
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			break RequestLoop
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		case UndoFailed:
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			x.Logger.Print("Walk terminated with UndoFailed")
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			break RequestLoop
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		case AuthorizationError:
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			x.Logger.Print("Walk terminated with AuthorizationError")
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			break RequestLoop
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		case NotWritable:
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			x.Logger.Print("Walk terminated with NotWritable")
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			break RequestLoop
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		case InconsistentName:
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			x.Logger.Print("Walk terminated with InconsistentName")
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			break RequestLoop
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		case NoError:
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			x.Logger.Print("Walk completed with NoError")
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		}
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		for i, pdu := range response.Variables {
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			if pdu.Type == EndOfMibView || pdu.Type == NoSuchObject || pdu.Type == NoSuchInstance {
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				x.Logger.Printf("BulkWalk terminated with type 0x%x", pdu.Type)
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				break RequestLoop
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			}
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			if !strings.HasPrefix(pdu.Name, rootOid+".") {
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				// Not in the requested root range.
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				// if this is the first request, and the first variable in that request
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				// and this condition is triggered - the first result is out of range
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				// need to perform a regular get request
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				// this request has been too narrowly defined to be found with a getNext
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				// Issue #78 #93
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				if requests == 1 && i == 0 {
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					getRequestType = GetRequest
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					continue RequestLoop
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				} else if pdu.Name == rootOid && pdu.Type != NoSuchInstance {
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					// Call walk function if the pdu instance is found
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					// considering that the rootOid is a leafOid
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					if err := walkFn(pdu); err != nil {
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						return err
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					}
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				}
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				break RequestLoop
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			}
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			if checkIncreasing && pdu.Name == oid {
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				return fmt.Errorf("OID not increasing: %s", pdu.Name)
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			}
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			// Report our pdu
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			if err := walkFn(pdu); err != nil {
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				return err
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			}
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		}
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		// Save last oid for next request
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		oid = response.Variables[len(response.Variables)-1].Name
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	}
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	x.Logger.Printf("BulkWalk completed in %d requests", requests)
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	return nil
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}
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func (x *GoSNMP) walkAll(getRequestType PDUType, rootOid string) (results []SnmpPDU, err error) {
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	err = x.walk(getRequestType, rootOid, func(dataUnit SnmpPDU) error {
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		results = append(results, dataUnit)
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		return nil
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	})
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	return results, err
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}
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