cmk_base/snmp_scan.py

   1 #!/usr/bin/python
   2 # -*- encoding: utf-8; py-indent-offset: 4 -*-
   3 # +------------------------------------------------------------------+
   4 # |             ____ _               _        __  __ _  __           |
   5 # |            / ___| |__   ___  ___| | __   |  \/  | |/ /           |
   6 # |           | |   | '_ \ / _ \/ __| |/ /   | |\/| | ' /            |
   7 # |           | |___| | | |  __/ (__|   <    | |  | | . \            |
   8 # |            \____|_| |_|\___|\___|_|\_\___|_|  |_|_|\_\           |
   9 # |                                                                  |
  10 # | Copyright Mathias Kettner 2014             mk@mathias-kettner.de |
  11 # +------------------------------------------------------------------+
  12 #
  13 # This file is part of Check_MK.
  14 # The official homepage is at http://mathias-kettner.de/check_mk.
  15 #
  16 # check_mk is free software;  you can redistribute it and/or modify it
  17 # under the  terms of the  GNU General Public License  as published by
  18 # the Free Software Foundation in version 2.  check_mk is  distributed
  19 # in the hope that it will be useful, but WITHOUT ANY WARRANTY;  with-
  20 # out even the implied warranty of  MERCHANTABILITY  or  FITNESS FOR A
  21 # PARTICULAR PURPOSE. See the  GNU General Public License for more de-
  22 # tails. You should have  received  a copy of the  GNU  General Public
  23 # License along with GNU Make; see the file  COPYING.  If  not,  write
  24 # to the Free Software Foundation, Inc., 51 Franklin St,  Fifth Floor,
  25 # Boston, MA 02110-1301 USA.
  26
  27 from cmk.utils.exceptions import MKGeneralException
  28 import cmk.utils.tty as tty
  29
  30 import cmk_base.check_utils
  31 import cmk_base.config as config
  32 import cmk_base.console as console
  33 from cmk_base.exceptions import MKSNMPError
  34 import cmk_base.snmp as snmp
  35 import cmk_base.check_api_utils as check_api_utils
  36
  37
  38 # gather auto_discovered check_plugin_names for this host
  39 def gather_snmp_check_plugin_names(host_config,
  40                                    on_error,
  41                                    do_snmp_scan,
  42                                    for_inventory=False,
  43                                    for_mgmt_board=False):
  44     check_plugin_names = set()
  45
  46     try:
  47         check_plugin_names.update(
  48             _snmp_scan(
  49                 host_config,
  50                 on_error=on_error,
  51                 do_snmp_scan=do_snmp_scan,
  52                 for_inv=for_inventory,
  53                 for_mgmt_board=for_mgmt_board))
  54     except Exception as e:
  55         if on_error == "raise":
  56             raise
  57         elif on_error == "warn":
  58             console.error("SNMP scan failed: %s\n" % e)
  59
  60     return list(check_plugin_names)
  61
  62
  63 def _snmp_scan(host_config,
  64                on_error="ignore",
  65                for_inv=False,
  66                do_snmp_scan=True,
  67                for_mgmt_board=False):
  68     import cmk_base.inventory_plugins as inventory_plugins
  69
  70     # Make hostname globally available for scan functions.
  71     # This is rarely used, but e.g. the scan for if/if64 needs
  72     # this to evaluate if_disabled_if64_checks.
  73     check_api_utils.set_hostname(host_config.hostname)
  74
  75     snmp.initialize_single_oid_cache(host_config)
  76     console.vverbose("  SNMP scan:\n")
  77     if not config.in_binary_hostlist(host_config.hostname, config.snmp_without_sys_descr):
  78         for oid, name in [(".1.3.6.1.2.1.1.1.0", "system description"),
  79                           (".1.3.6.1.2.1.1.2.0", "system object")]:
  80             value = snmp.get_single_oid(host_config, oid, do_snmp_scan=do_snmp_scan)
  81             if value is None:
  82                 raise MKSNMPError(
  83                     "Cannot fetch %s OID %s. This might be OK for some bogus devices. "
  84                     "In that case please configure the ruleset \"Hosts without system "
  85                     "description OID\" to tell Check_MK not to fetch the system "
  86                     "description and system object OIDs." % (name, oid))
  87     else:
  88         # Fake OID values to prevent issues with a lot of scan functions
  89         console.vverbose("       Skipping system description OID "
  90                          "(Set .1.3.6.1.2.1.1.1.0 and .1.3.6.1.2.1.1.2.0 to \"\")\n")
  91         snmp.set_single_oid_cache(host_config, ".1.3.6.1.2.1.1.1.0", "")
  92         snmp.set_single_oid_cache(host_config, ".1.3.6.1.2.1.1.2.0", "")
  93
  94     found_check_plugin_names = []
  95     if for_inv:
  96         items = inventory_plugins.inv_info.items()
  97     else:
  98         items = config.check_info.items()
  99
 100     positive_found = []
 101     default_found = []
 102
 103     for check_plugin_name, _unused_check in items:
 104         if config.service_ignored(host_config.hostname, check_plugin_name, None):
 105             continue
 106         else:
 107             if for_inv and not inventory_plugins.is_snmp_plugin(check_plugin_name):
 108                 continue
 109             elif not for_inv and not cmk_base.check_utils.is_snmp_check(check_plugin_name):
 110                 continue
 111
 112         section_name = cmk_base.check_utils.section_name_of(check_plugin_name)
 113         # The scan function should be assigned to the section_name, because
 114         # subchecks sharing the same SNMP info of course should have
 115         # an identical scan function. But some checks do not do this
 116         # correctly
 117         if check_plugin_name in config.snmp_scan_functions:
 118             scan_function = config.snmp_scan_functions[check_plugin_name]
 119         elif section_name in config.snmp_scan_functions:
 120             scan_function = config.snmp_scan_functions[section_name]
 121         elif section_name in inventory_plugins.inv_info:
 122             scan_function = inventory_plugins.inv_info[section_name].get("snmp_scan_function")
 123         else:
 124             scan_function = None
 125
 126         if scan_function:
 127             try:
 128
 129                 def oid_function(oid, default_value=None, cp_name=check_plugin_name):
 130                     value = snmp.get_single_oid(
 131                         host_config, oid, cp_name, do_snmp_scan=do_snmp_scan)
 132                     return default_value if value is None else value
 133
 134                 result = scan_function(oid_function)
 135                 if result is not None and not isinstance(result, (str, bool)):
 136                     if on_error == "warn":
 137                         console.warning("   SNMP scan function of %s returns invalid type %s." %
 138                                         (check_plugin_name, type(result)))
 139                     elif on_error == "raise":
 140                         raise MKGeneralException("SNMP Scan aborted.")
 141                 elif result:
 142                     found_check_plugin_names.append(check_plugin_name)
 143                     positive_found.append(check_plugin_name)
 144             except MKGeneralException:
 145                 # some error messages which we explicitly want to show to the user
 146                 # should be raised through this
 147                 raise
 148             except:
 149                 if on_error == "warn":
 150                     console.warning("   Exception in SNMP scan function of %s" % check_plugin_name)
 151                 elif on_error == "raise":
 152                     raise
 153         else:
 154             found_check_plugin_names.append(check_plugin_name)
 155             default_found.append(check_plugin_name)
 156
 157     _output_snmp_check_plugins("SNMP scan found", positive_found)
 158     if default_found:
 159         _output_snmp_check_plugins("SNMP without scan function", default_found)
 160
 161     filtered = config.filter_by_management_board(
 162         host_config.hostname,
 163         found_check_plugin_names,
 164         for_mgmt_board,
 165         for_discovery=True,
 166         for_inventory=for_inv)
 167
 168     _output_snmp_check_plugins("SNMP filtered check plugin names", filtered)
 169     snmp.write_single_oid_cache(host_config)
 170     return sorted(filtered)
 171
 172
 173 def _output_snmp_check_plugins(title, collection):
 174     if collection:
 175         collection_out = " ".join(sorted(collection))
 176     else:
 177         collection_out = "-"
 178     console.vverbose("   %-35s%s%s%s%s\n" % \
 179                     (title, tty.bold, tty.yellow, collection_out, tty.normal))