""" This module is used to auto-detect the type of a device in order to automatically create a Netmiko connection. This avoids hard coding the 'device_type' when using the ConnectHandler factory function from Netmiko. Example: ------------------ from netmiko.snmp_autodetect import SNMPDetect my_snmp = SNMPDetect(hostname='1.1.1.70', user='pysnmp', auth_key='key1', encrypt_key='key2') device_type = my_snmp.autodetect() ------------------ autodetect will return None if no match. SNMPDetect class defaults to SNMPv3 Note, pysnmp is a required dependency for SNMPDetect and is intentionally not included in netmiko requirements. So installation of pysnmp might be required. """ from typing import Optional, Dict, List from typing.re import Pattern import asyncio import re import socket try: from pysnmp.entity.rfc3413.oneliner import cmdgen SNMP_MODE = "legacy" except ImportError: from pysnmp.hlapi.asyncio import cmdgen SNMP_MODE = "v6_async" except ImportError: raise ImportError("pysnmp not installed; please install it: 'pip install pysnmp'") from netmiko.ssh_dispatcher import CLASS_MAPPER # Higher priority indicates a better match. SNMP_MAPPER_BASE = { "arista_eos": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Arista Networks EOS.*", re.IGNORECASE), "priority": 99, }, "allied_telesis_awplus": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*AlliedWare Plus.*", re.IGNORECASE), "priority": 99, }, "paloalto_panos": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Palo Alto Networks.*", re.IGNORECASE), "priority": 99, }, "hp_comware": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*HP(E)? Comware.*", re.IGNORECASE), "priority": 99, }, "hp_procurve": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".ProCurve", re.IGNORECASE), "priority": 99, }, "cisco_ios": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Cisco IOS Software.*,.*", re.IGNORECASE), "priority": 60, }, "cisco_xe": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*IOS-XE Software,.*", re.IGNORECASE), "priority": 99, }, "cisco_xr": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Cisco IOS XR Software.*", re.IGNORECASE), "priority": 99, }, "cisco_asa": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Cisco Adaptive Security Appliance.*", re.IGNORECASE), "priority": 99, }, "cisco_nxos": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Cisco NX-OS.*", re.IGNORECASE), "priority": 99, }, "cisco_wlc": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Cisco Controller.*", re.IGNORECASE), "priority": 99, }, "f5_tmsh": { "oid": ".1.3.6.1.4.1.3375.2.1.4.1.0", "expr": re.compile(r".*BIG-IP.*", re.IGNORECASE), "priority": 99, }, "fortinet": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r"Forti.*", re.IGNORECASE), "priority": 80, }, "checkpoint": { "oid": ".1.3.6.1.4.1.2620.1.6.16.9.0", "expr": re.compile(r"CheckPoint"), "priority": 79, }, "juniper_junos": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*Juniper.*"), "priority": 99, }, "nokia_sros": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*TiMOS.*"), "priority": 99, }, "dell_powerconnect": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r"PowerConnect.*", re.IGNORECASE), "priority": 50, }, "mikrotik_routeros": { "oid": ".1.3.6.1.2.1.1.1.0", "expr": re.compile(r".*RouterOS.*", re.IGNORECASE), "priority": 60, }, } # Ensure all SNMP device types are supported by Netmiko SNMP_MAPPER = {} std_device_types = list(CLASS_MAPPER.keys()) for device_type in std_device_types: if SNMP_MAPPER_BASE.get(device_type): SNMP_MAPPER[device_type] = SNMP_MAPPER_BASE[device_type] def identify_address_type(entry: str) -> List[str]: """ Return a list containing all ip types found. An empty list means no valid ip were found Parameters ---------- entry: str Can be an ipv4, an ipv6 or an FQDN. Returns ------- list of string: list A list of string 'IPv4' | 'IPv6' which indicates if entry is a valid ipv4 and/or ipv6. """ try: socket.inet_pton(socket.AF_INET, entry) return ["IPv4"] except socket.error: pass try: socket.inet_pton(socket.AF_INET6, entry) return ["IPv6"] except socket.error: pass ip_types = [] try: addrinfo = socket.getaddrinfo(entry, None) for info in addrinfo: ip = info[4][0] try: socket.inet_pton(socket.AF_INET, ip) ip_types.append("IPv4") except socket.error: pass try: socket.inet_pton(socket.AF_INET6, ip) ip_types.append("IPv6") except socket.error: pass except socket.gaierror: pass return ip_types class SNMPDetect(object): """ The SNMPDetect class tries to automatically determine the device type. Typically this will use the MIB-2 SysDescr and regular expressions. Parameters ---------- hostname: str The name or IP address of the hostname we want to guess the type snmp_version : str, optional ('v1', 'v2c' or 'v3') The SNMP version that is running on the device (default: 'v3') snmp_port : int, optional The UDP port on which SNMP is listening (default: 161) community : str, optional The SNMP read community when using SNMPv2 (default: None) user : str, optional The SNMPv3 user for authentication (default: '') auth_key : str, optional The SNMPv3 authentication key (default: '') encrypt_key : str, optional The SNMPv3 encryption key (default: '') auth_proto : str, optional ('des', '3des', 'aes128', 'aes192', 'aes256') The SNMPv3 authentication protocol (default: 'aes128') encrypt_proto : str, optional ('sha', 'md5') The SNMPv3 encryption protocol (default: 'sha') Attributes ---------- hostname: str The name or IP address of the device we want to guess the type snmp_version : str The SNMP version that is running on the device snmp_port : int The UDP port on which SNMP is listening community : str The SNMP read community when using SNMPv2 user : str The SNMPv3 user for authentication auth_key : str The SNMPv3 authentication key encrypt_key : str The SNMPv3 encryption key auth_proto : str The SNMPv3 authentication protocol encrypt_proto : str The SNMPv3 encryption protocol Methods ------- autodetect() Try to determine the device type. """ def __init__( self, hostname: str, snmp_version: str = "v3", snmp_port: int = 161, community: Optional[str] = None, user: str = "", auth_key: str = "", encrypt_key: str = "", auth_proto: str = "sha", encrypt_proto: str = "aes128", ) -> None: # Check that the SNMP version is matching predefined type or raise ValueError if snmp_version == "v1" or snmp_version == "v2c": if not community: raise ValueError("SNMP version v1/v2c community must be set.") elif snmp_version == "v3": if not user: raise ValueError("SNMP version v3 user and password must be set") else: raise ValueError("SNMP version must be set to 'v1', 'v2c' or 'v3'") # Check that the SNMPv3 auth & priv parameters match allowed types self._snmp_v3_authentication = { "sha": cmdgen.usmHMACSHAAuthProtocol, "md5": cmdgen.usmHMACMD5AuthProtocol, } self._snmp_v3_encryption = { "des": cmdgen.usmDESPrivProtocol, "3des": cmdgen.usm3DESEDEPrivProtocol, "aes128": cmdgen.usmAesCfb128Protocol, "aes192": cmdgen.usmAesCfb192Protocol, "aes256": cmdgen.usmAesCfb256Protocol, } if auth_proto not in self._snmp_v3_authentication.keys(): raise ValueError( "SNMP V3 'auth_proto' argument must be one of the following: {}".format( self._snmp_v3_authentication.keys() ) ) if encrypt_proto not in self._snmp_v3_encryption.keys(): raise ValueError( "SNMP V3 'encrypt_proto' argument must be one of the following: {}".format( self._snmp_v3_encryption.keys() ) ) self.hostname = hostname self.snmp_version = snmp_version self.snmp_port = snmp_port self.community = community self.user = user self.auth_key = auth_key self.encrypt_key = encrypt_key self.auth_proto = self._snmp_v3_authentication[auth_proto] self.encryp_proto = self._snmp_v3_encryption[encrypt_proto] self._response_cache: Dict[str, str] = {} self.snmp_target = (self.hostname, self.snmp_port) if "IPv6" in identify_address_type(self.hostname): self.udp_transport_target = cmdgen.Udp6TransportTarget( self.snmp_target, timeout=1.5, retries=2 ) else: self.udp_transport_target = cmdgen.UdpTransportTarget( self.snmp_target, timeout=1.5, retries=2 ) async def _run_query(self, creds: object, oid: str) -> str: """ Asynchronous getCmd query to the device. Parameters ---------- creds : UsmUserData or CommunityData object The authentication credentials. oid : str The SNMP OID that you want to get. Returns ------- string : str The string as part of the value from the OID you are trying to retrieve. """ errorIndication, errorStatus, errorIndex, varBinds = await cmdgen.getCmd( cmdgen.SnmpEngine(), creds, self.udp_transport_target, cmdgen.ContextData(), cmdgen.ObjectType(cmdgen.ObjectIdentity(oid)), ) if not errorIndication and varBinds[0][1]: return str(varBinds[0][1]) return "" def _get_snmpv3_asyncwr(self, oid: str) -> str: """ This is an asynchronous wrapper to call code in newer versions of the pysnmp library (V6 and later). """ return asyncio.run( self._run_query( cmdgen.UsmUserData( self.user, self.auth_key, self.encrypt_key, authProtocol=self.auth_proto, privProtocol=self.encryp_proto, ), oid, ) ) def _get_snmpv3(self, oid: str) -> str: """ Try to send an SNMP GET operation using SNMPv3 for the specified OID. Parameters ---------- oid : str The SNMP OID that you want to get. Returns ------- string : str The string as part of the value from the OID you are trying to retrieve. """ if SNMP_MODE == "legacy": cmd_gen = cmdgen.CommandGenerator() (error_detected, error_status, error_index, snmp_data) = cmd_gen.getCmd( cmdgen.UsmUserData( self.user, self.auth_key, self.encrypt_key, authProtocol=self.auth_proto, privProtocol=self.encryp_proto, ), self.udp_transport_target, oid, lookupNames=True, lookupValues=True, ) if not error_detected and snmp_data[0][1]: return str(snmp_data[0][1]) return "" elif SNMP_MODE == "v6_async": return self._get_snmpv3_asyncwr(oid=oid) else: raise ValueError("SNMP mode must be set to 'legacy' or 'v6_async'") def _get_snmpv2c_asyncwr(self, oid: str) -> str: """ This is an asynchronous wrapper to call code in newer versions of the pysnmp library (V6 and later). """ return asyncio.run(self._run_query(cmdgen.CommunityData(self.community), oid)) def _get_snmpv2c(self, oid: str) -> str: """ Try to send an SNMP GET operation using SNMPv2 for the specified OID. Parameters ---------- oid : str The SNMP OID that you want to get. Returns ------- string : str The string as part of the value from the OID you are trying to retrieve. """ if SNMP_MODE == "legacy": cmd_gen = cmdgen.CommandGenerator() (error_detected, error_status, error_index, snmp_data) = cmd_gen.getCmd( cmdgen.CommunityData(self.community), self.udp_transport_target, oid, lookupNames=True, lookupValues=True, ) if not error_detected and snmp_data[0][1]: return str(snmp_data[0][1]) return "" elif SNMP_MODE == "v6_async": return self._get_snmpv2c_asyncwr(oid=oid) else: raise ValueError("SNMP mode must be set to 'legacy' or 'v6_async'") def _get_snmp(self, oid: str) -> str: """Wrapper for generic SNMP call.""" if self.snmp_version in ["v1", "v2c"]: return self._get_snmpv2c(oid) else: return self._get_snmpv3(oid) def autodetect(self) -> Optional[str]: """ Try to guess the device_type using SNMP GET based on the SNMP_MAPPER dict. The type which is returned is directly matching the name in *netmiko.ssh_dispatcher.CLASS_MAPPER_BASE* dict. Thus you can use this name to retrieve automatically the right ConnectionClass Returns ------- potential_type : str The name of the device_type that must be running. """ # Convert SNMP_MAPPER to a list and sort by priority snmp_mapper_orig = [] for k, v in SNMP_MAPPER.items(): snmp_mapper_orig.append({k: v}) snmp_mapper_list = sorted( snmp_mapper_orig, key=lambda x: list(x.values())[0]["priority"] # type: ignore ) snmp_mapper_list.reverse() for entry in snmp_mapper_list: for device_type, v in entry.items(): oid: str = v["oid"] # type: ignore regex: Pattern = v["expr"] # Used cache data if we already queryied this OID if self._response_cache.get(oid): snmp_response = self._response_cache.get(oid) else: snmp_response = self._get_snmp(oid) self._response_cache[oid] = snmp_response # See if we had a match assert isinstance(snmp_response, str) if re.search(regex, snmp_response): assert isinstance(device_type, str) return device_type return None