diff options
Diffstat (limited to 'pysnmp/entity/rfc3413/cmdrsp.py')
| -rw-r--r-- | pysnmp/entity/rfc3413/cmdrsp.py | 219 |
1 files changed, 153 insertions, 66 deletions
diff --git a/pysnmp/entity/rfc3413/cmdrsp.py b/pysnmp/entity/rfc3413/cmdrsp.py index e2d47f38..0aa3b1e1 100644 --- a/pysnmp/entity/rfc3413/cmdrsp.py +++ b/pysnmp/entity/rfc3413/cmdrsp.py @@ -9,6 +9,7 @@ from pysnmp.proto import rfc1902, rfc1905, rfc3411, errind, error from pysnmp.proto.api import v2c # backend is always SMIv2 compliant from pysnmp.proto.proxy import rfc2576 import pysnmp.smi.error +from pysnmp.smi import exval from pysnmp import debug @@ -158,22 +159,33 @@ class CommandResponderBase(object): self.initiateMgmtOperation(snmpEngine, stateReference, contextName, PDU) + @staticmethod + def _storeAccessContext(snmpEngine): + """Copy received message metadata while it lasts""" + execCtx = snmpEngine.observer.getExecutionContext('rfc3412.receiveMessage:request') + return { + 'securityModel': execCtx['securityModel'], + 'securityName': execCtx['securityName'], + 'securityLevel': execCtx['securityLevel'], + 'contextName': execCtx['contextName'], + 'pduType': execCtx['pdu'].getTagSet() + } + @classmethod def verifyAccess(cls, viewType, varBind, **context): name, val = varBind snmpEngine = context['snmpEngine'] - execCtx = snmpEngine.observer.getExecutionContext('rfc3412.receiveMessage:request') (securityModel, securityName, securityLevel, contextName, - pduType) = (execCtx['securityModel'], - execCtx['securityName'], - execCtx['securityLevel'], - execCtx['contextName'], - execCtx['pdu'].getTagSet()) + pduType) = (context['securityModel'], + context['securityName'], + context['securityLevel'], + context['contextName'], + context['pduType']) try: snmpEngine.accessControlModel[cls.acmID].isAccessAllowed( @@ -221,44 +233,25 @@ class CommandResponderBase(object): def _getMgmtFun(self, contextName): return lambda *args, **kwargs: None - def _checkSmiErrors(self, varBinds): + def _mapSmiErrors(self, varBinds, **context): errorIndication = None errorStatus = errorIndex = 0 - exception = None - - for idx, varBind in enumerate(varBinds): - name, value = varBind - if isinstance(value, tuple): # expect exception tuple - debug.logger & debug.flagApp and debug.logger( - '_checkSmiErrors: exception reported for OID %s exception %s' % (name, value)) - - if not exception: - exception = value - - # reset exception object - varBinds[idx] = name, v2c.null + errors = context.get('errors') + if not errors: + return errorIndication, errorStatus, errorIndex - try: - # TODO: perhaps chain exceptions - if exception: - debug.logger & debug.flagApp and debug.logger( - '_checkSmiErrors: re-raising exception %s' % (exception,)) - raise exception[1].with_traceback(exception[2]) - - # SNMPv2 SMI exceptions - except pysnmp.smi.error.GenError: - errorIndication = sys.exc_info()[1] - debug.logger & debug.flagApp and debug.logger( - '_checkSmiErrors: errorIndication %s' % (errorIndication,)) + # Take the latest exception + err = errors[-1] - except pysnmp.smi.error.SmiError: - exc_type, exc_obj, trb = sys.exc_info() + if isinstance(err, pysnmp.smi.error.GenError): + errorIndication = str(err) - errorStatus = self.SMI_ERROR_MAP.get(exc_type, 'genErr') + elif isinstance(err, pysnmp.smi.error.SmiError): + errorStatus = self.SMI_ERROR_MAP.get(err.__class__, 'genErr') try: - errorIndex = exc_obj['idx'] + 1 + errorIndex = err['idx'] + 1 except IndexError: errorIndex = len(varBinds) and 1 or 0 @@ -267,13 +260,8 @@ class CommandResponderBase(object): def completeMgmtOperation(self, varBinds, **context): - try: - (errorIndication, - errorStatus, errorIndex) = self._checkSmiErrors(varBinds) - - except pysnmp.error.PySnmpError: - self.releaseStateInformation(context['stateReference']) - return + (errorIndication, + errorStatus, errorIndex) = self._mapSmiErrors(varBinds, **context) stateReference = context['stateReference'] @@ -304,6 +292,8 @@ class CommandResponderBase(object): cbFun=self.completeMgmtOperation, cbCtx=self.cbCtx) + context.update(self._storeAccessContext(snmpEngine)) + mgmtFun(*varBinds, **context) @@ -312,7 +302,7 @@ class GetCommandResponder(CommandResponderBase): # rfc1905: 4.2.1 def _getMgmtFun(self, contextName): - return self.snmpContext.getMibInstrum(contextName).readVars + return self.snmpContext.getMibInstrum(contextName).readMibObjects class NextCommandResponder(CommandResponderBase): @@ -320,41 +310,133 @@ class NextCommandResponder(CommandResponderBase): # rfc1905: 4.2.2 def _getMgmtFun(self, contextName): - return self.snmpContext.getMibInstrum(contextName).readNextVars + return self.snmpContext.getMibInstrum(contextName).readNextMibObjects + + def _getManagedObjectsInstances(self, varBinds, **context): + """Iterate over Managed Objects fulfilling SNMP query. + + Parameters + ---------- + varBinds + context + + Returns + ------- + :py:class:`list` - List of Managed Objects Instances to respond with or + `None` to indicate that not all objects have been gathered + so far. + """ + rspVarBinds = context['rspVarBinds'] + varBindsMap = context['varBindsMap'] + + rtrVarBinds = [] + + for idx, varBind in enumerate(varBinds): + name, val = varBind + if (exval.noSuchObject.isSameTypeWith(val) or + exval.noSuchInstance.isSameTypeWith(val)): + varBindsMap[len(rtrVarBinds)] = varBindsMap.pop(idx, idx) + rtrVarBinds.append(varBind) + + else: + rspVarBinds[varBindsMap.pop(idx, idx)] = varBind + + if rtrVarBinds: + snmpEngine = context['snmpEngine'] + + # Need to unwind stack, can't recurse any more + def callLater(*args): + snmpEngine.transportDispatcher.unregisterTimerCbFun(callLater) + mgmtFun = context['mgmtFun'] + mgmtFun(*varBinds, **context) + + snmpEngine.transportDispatcher.registerTimerCbFun(callLater, 0.01) + + else: + return rspVarBinds + + def completeMgmtOperation(self, varBinds, **context): + rspVarBinds = self._getManagedObjectsInstances(varBinds, **context) + if rspVarBinds: + CommandResponderBase.completeMgmtOperation(self, rspVarBinds, **context) + + def initiateMgmtOperation(self, snmpEngine, stateReference, contextName, PDU): + varBinds = v2c.apiPDU.getVarBinds(PDU) + + mgmtFun = self._getMgmtFun(contextName) + + context = dict(snmpEngine=snmpEngine, + stateReference=stateReference, + acFun=self.verifyAccess, + cbFun=self.completeMgmtOperation, + cbCtx=self.cbCtx, + rspVarBinds=varBinds[:], + varBindsMap={}, + mgmtFun=mgmtFun) + + context.update(self._storeAccessContext(snmpEngine)) + mgmtFun(*varBinds, **context) -class BulkCommandResponder(CommandResponderBase): + +class BulkCommandResponder(NextCommandResponder): SUPPORTED_PDU_TYPES = (rfc1905.GetBulkRequestPDU.tagSet,) maxVarBinds = 64 - def _getMgmtFun(self, contextName): - return self.snmpContext.getMibInstrum(contextName).readNextVars - def _completeNonRepeaters(self, varBinds, **context): - context['rspVarBinds'][:] = varBinds + mgmtFun = context['mgmtFun'] - if context['counters']['M'] and context['counters']['R']: - context['cbFun'] = self.completeMgmtOperation + if not varBinds: + # No non-repeaters requested, proceed with repeaters + mgmtFun(*context['reqVarBinds'], + **dict(context, cbFun=self.completeMgmtOperation, + varBinds=context['reqVarBinds'][:])) + return - mgmtFun = self._getMgmtFun(context['contextName']) + rspVarBinds = self._getManagedObjectsInstances(varBinds, **context) + if rspVarBinds: + context['allVarBinds'].extend(rspVarBinds) - mgmtFun(*context['reqVarBinds'], **context) + if context['counters']['M'] and context['counters']['R']: - else: - CommandResponderBase.completeMgmtOperation(self, context['rspVarBinds'], **context) + rspVarBinds = self._getManagedObjectsInstances(varBinds, **context) + if rspVarBinds: + # Done with non-repeaters, proceed with repeaters + mgmtFun(*context['reqVarBinds'], + **dict(context, + cbFun=self.completeMgmtOperation, + varBindsMap={}, + rspVarBinds=context['reqVarBinds'][:])) + return + + else: + CommandResponderBase.completeMgmtOperation(self, context['allVarBinds'], **context) def completeMgmtOperation(self, varBinds, **context): - context['rspVarBinds'].extend(varBinds) - context['counters']['M'] -= 1 + rspVarBinds = self._getManagedObjectsInstances(varBinds, **context) + if rspVarBinds: + context['counters']['M'] -= 1 - if context['counters']['M'] and context['counters']['R']: - mgmtFun = self._getMgmtFun(context['contextName']) + context['allVarBinds'].extend(rspVarBinds) - context['cbFun'] = self.completeMgmtOperation - mgmtFun(*varBinds[-context['counters']['R']:], **context) + eom = all(exval.endOfMibView.isSameTypeWith(value) for name, value in rspVarBinds) - else: - CommandResponderBase.completeMgmtOperation(self, context['rspVarBinds'], **context) + if not eom and context['counters']['M'] and context['counters']['R']: + snmpEngine = context['snmpEngine'] + + # Need to unwind stack, can't recurse any more + def callLater(*args): + snmpEngine.transportDispatcher.unregisterTimerCbFun(callLater) + mgmtFun = context['mgmtFun'] + reqVarBinds = varBinds[-context['counters']['R']:] + mgmtFun(*reqVarBinds, + **dict(context, cbFun=self.completeMgmtOperation, + varBindsMap={}, rspVarBinds=reqVarBinds[:])) + + snmpEngine.transportDispatcher.registerTimerCbFun(callLater, 0.01) + + else: + CommandResponderBase.completeMgmtOperation(self, context['allVarBinds'], **context) # rfc1905: 4.2.3 def initiateMgmtOperation(self, snmpEngine, stateReference, contextName, PDU): @@ -388,7 +470,12 @@ class BulkCommandResponder(CommandResponderBase): cbCtx=self.cbCtx, reqVarBinds=varBinds[N:], counters={'M': M, 'R': R}, - rspVarBinds=[]) + rspVarBinds=varBinds[N:], + allVarBinds=[], + varBindsMap={}, + mgmtFun=mgmtFun) + + context.update(self._storeAccessContext(snmpEngine)) mgmtFun(*varBinds[:N], **context) @@ -404,4 +491,4 @@ class SetCommandResponder(CommandResponderBase): # rfc1905: 4.2.5.1-13 def _getMgmtFun(self, contextName): - return self.snmpContext.getMibInstrum(contextName).writeVars + return self.snmpContext.getMibInstrum(contextName).writeMibObjects |