def __reader(struct_definition: Struct, output_tuple: namedtuple,
data) -> namedtuple:
"""Helper function for building out struct reader functions"""
return output_tuple._make(struct_definition.unpack(data))
def unpack_named(data: bytes, packing: str, nt: namedtuple):
return [nt._make(x) for x in struct.iter_unpack(packing, data)]
class v2c(object):
"""Build an SNMPv2c manager object"""
def __init__(self, ipaddr=None, device=None, community='Public',
retries=3, timeout=9):
self.device = device
self.ipaddr = ipaddr
self.community = community
self.SNMPObject = NT('SNMPObject', ['modName', 'datetime', 'symName',
'index', 'value'])
self.SNMPIndexed = NT('SNMPIndexed', ['modName', 'datetime', 'symName',
'index', 'value'])
self.query_timeout = float(timeout)/int(retries)
self.query_retries = int(retries)
self._index = None
self.cmdGen = cmdgen.CommandGenerator()
#mibBuilder = builder.MibBuilder()
#mibPath = mibBuilder.getMibPath()+('/opt/python/Models/Network/MIBs',)
#mibBuilder.setMibPath(*mibPath)
#mibBuilder.loadModules(
# 'RFC-1213',
# )
#mibView = view.MibViewController(mibBuilder)
def index(self, oid=None):
"""Build an SNMP Manager index to reference in get or walk operations. First v2c.index('ifName'). Then, v2c.get_index('ifHCInOctets', 'eth0') or v2c.walk_index('ifHCInOctets'). Instead of referencing a numerical index, the index will refer to the value that was indexed."""
self._index = dict()
self._intfobj = dict()
snmpidx = self.walk(oid=oid)
for ii in snmpidx:
## the dicts below are keyed by the SNMP index number
# value below is the text string of the intf name
self._index[ii.index] = ii.value
# value below is the intf object
if not (self.device is None):
self._intfobj[ii.index] = self.device.find_match_intf(ii.value,
enforce_format=False)
def walk_index(self, oid=None):
"""Example usage, first index with v2c.index('ifName'), then v2c.get_index('ifHCInOctets', 'eth0')"""
if not (self._index is None):
tmp = list()
snmpvals = self.walk(oid=oid)
for idx, ii in enumerate(snmpvals):
tmp.append([ii.modName, datetime.now(), ii.symName,
self._index[ii.index], ii.value])
return map(self.SNMPIndexed._make, tmp)
else:
raise ValueError, "Must populate with SNMP.v2c.index() first"
def walk(self, oid=None):
if isinstance(self._format(oid), tuple):
errorIndication, errorStatus, errorIndex, \
varBindTable = self.cmdGen.nextCmd(
cmdgen.CommunityData('test-agent', self.community),
cmdgen.UdpTransportTarget((self.ipaddr, 161),
retries=self.query_retries,
timeout=self.query_timeout),
self._format(oid),
)
# Parsing only for now... no return value...
self._parse(errorIndication, errorStatus, errorIndex, varBindTable)
elif isinstance(oid, str):
errorIndication, errorStatus, errorIndex, \
varBindTable = self.cmdGen.nextCmd(
# SNMP v2
cmdgen.CommunityData('test-agent', self.community),
# Transport
cmdgen.UdpTransportTarget((self.ipaddr, 161)),
(('', oid),),
#cmdgen.MibVariable(oid).loadMibs(),
)
return self._parse_resolve(errorIndication, errorStatus,
errorIndex, varBindTable)
else:
raise ValueError, "Unknown oid format: %s" % oid
def get_index(self, oid=None, index=None):
"""In this case, index should be similar to the values you indexed from... i.e. if you index with ifName, get_index('ifHCInOctets', 'eth0')"""
if not (self._index is None) and isinstance(index, str):
# Map the interface name provided in index to an ifName index...
snmpvals = None
for idx, value in self._index.items():
if index == value:
# if there is an exact match between the text index and the
# snmp index value...
snmpvals = self.get(oid=oid, index=idx)
break
else:
# TRY mapping the provided text index into an interface obj
_intfobj = self.device.find_match_intf(index)
if not (_intfobj is None):
for key, val in self._intfobj.items():
if (val==_intfobj):
snmpvals = self.get(oid=oid, index=key)
break
# Ensure we only parse a valid response...
if not (snmpvals is None):
tmp = [snmpvals.modName, datetime.now(), snmpvals.symName,
self._index[snmpvals.index], snmpvals.value]
return self.SNMPIndexed._make(tmp)
elif not isinstance(index, str):
raise ValueError, "index must be a string value"
else:
raise ValueError, "Must populate with SNMP.v2c.index() first"
def get(self, oid=None, index=None):
if isinstance(self._format(oid), tuple):
errorIndication, errorStatus, errorIndex, \
varBindTable = self.cmdGen.getCmd(
cmdgen.CommunityData('test-agent', self.community),
cmdgen.UdpTransportTarget((self.ipaddr, 161),
retries=self.query_retries,
timeout=self.query_timeout),
self._format(oid),
)
# Parsing only for now... no return value...
self._parse(errorIndication, errorStatus, errorIndex, varBindTable)
elif isinstance(oid, str) and isinstance(index, int):
errorIndication, errorStatus, errorIndex, \
varBindTable = self.cmdGen.getCmd(
# SNMP v2
cmdgen.CommunityData('test-agent', self.community),
# Transport
cmdgen.UdpTransportTarget((self.ipaddr, 161)),
(('', oid), index),
#cmdgen.MibVariable(oid).loadMibs(),
)
return self._parse_resolve(errorIndication, errorStatus,
errorIndex, [varBindTable])[0]
else:
raise ValueError, "Unknown oid format: %s" % oid
def bulkwalk(self, oid=None):
"""SNMP bulkwalk a device. NOTE: This often is faster, but does not work as well as a simple SNMP walk"""
if isinstance(self._format(oid), tuple):
errorIndication, errorStatus, errorIndex, varBindTable = self.cmdGen.bulkCmd(
cmdgen.CommunityData('test-agent', self.community),
cmdgen.UdpTransportTarget((self.ipaddr, 161),
retries=self.query_retries,
timeout=self.query_timeout),
0,
25,
self._format(oid),
)
return self._parse(errorIndication, errorStatus,
errorIndex, varBindTable)
elif isinstance(oid, str):
errorIndication, errorStatus, errorIndex, varBindTable = self.cmdGen.bulkCmd(
cmdgen.CommunityData('test-agent', self.community),
cmdgen.UdpTransportTarget((self.ipaddr, 161),
retries=self.query_retries,
timeout=self.query_timeout),
0,
25,
(('', oid),),
#cmdgen.MibVariable(oid).loadMibs(),
)
return self._parse_resolve(errorIndication, errorStatus,
errorIndex, varBindTable)
else:
raise ValueError, "Unknown oid format: %s" % oid
def _parse_resolve(self, errorIndication=None, errorStatus=None,
errorIndex=None, varBindTable=None):
"""Parse MIB walks and resolve into MIB names"""
retval = list()
if errorIndication:
print errorIndication
else:
if errorStatus:
print '%s at %s\n' % (
errorStatus.prettyPrint(),
varBindTable[-1][int(errorIndex)-1]
)
else:
for varBindTableRow in varBindTable:
for oid, val in varBindTableRow:
(symName, modName), indices = cmdgen.mibvar.oidToMibName(
self.cmdGen.mibViewController, oid
)
val = cmdgen.mibvar.cloneFromMibValue(
self.cmdGen.mibViewController, modName, symName,
val)
# Try to parse the index as an int first,
# then as a string
try:
index = int(string.join(map(lambda v: v.prettyPrint(), indices), '.'))
except ValueError:
index = str(string.join(map(lambda v: v.prettyPrint(), indices), '.'))
# Re-format values as float or integer, if possible...
tmp = val.prettyPrint()
if re.search(r"""^\s*\d+\s*$""", tmp):
value = int64(tmp)
elif re.search(r"""^\s*\d+\.\d+\s*$""", tmp):
value = float64(tmp)
else:
value = tmp
retval.append(self.SNMPObject._make([modName,
datetime.now(), symName, index, value]))
return retval
def _parse(self, errorIndication, errorStatus, errorIndex,
varBindTable):
if errorIndication:
print errorIndication
else:
if errorStatus:
print '%s at %s\n' % (
errorStatus.prettyPrint(),
errorIndex and varBindTable[-1][int(errorIndex)-1] or '?'
)
else:
for varBindTableRow in varBindTable:
for name, val in varBindTableRow:
print '%s = %s' % (name.prettyPrint(), val.prettyPrint())
def _format(self, oid):
"""Format a numerical OID in the form of 1.3.4.1.2.1 into a tuple"""
if isinstance(oid, str):
if re.search('(\d+\.)+\d+', oid):
tmp = list()
for ii in oid.split('.'):
tmp.append(int(ii))
return tuple(tmp)
else:
return oid