verdec.py 文件源码

def decodeMessageVersion(wholeMsg):
    try:
        seq, wholeMsg = decoder.decode(
            wholeMsg, asn1Spec=univ.Sequence(),
            recursiveFlag=False, substrateFun=lambda a, b, c: (a, b[:c])
        )
        ver, wholeMsg = decoder.decode(
            wholeMsg, asn1Spec=univ.Integer(),
            recursiveFlag=False, substrateFun=lambda a, b, c: (a, b[:c])
        )
        if eoo.endOfOctets.isSameTypeWith(ver):
            raise ProtocolError('EOO at SNMP version component')
        return ver
    except PyAsn1Error:
        raise ProtocolError('Invalid BER at SNMP version component')