Thomas Patzke
120 lines
5.4 KiB
Python
120 lines
5.4 KiB
Python
# Output backends for sigmac
|
|
# Copyright 2016-2018 Thomas Patzke, Florian Roth, Roey
|
|
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU Lesser General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU Lesser General Public License for more details.
|
|
|
|
# You should have received a copy of the GNU Lesser General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
import re
|
|
import sigma
|
|
from .base import SingleTextQueryBackend
|
|
from .mixins import MultiRuleOutputMixin
|
|
|
|
class SplunkBackend(SingleTextQueryBackend):
|
|
"""Converts Sigma rule into Splunk Search Processing Language (SPL)."""
|
|
identifier = "splunk"
|
|
active = True
|
|
index_field = "index"
|
|
|
|
reEscape = re.compile('("|\\\\(?![*?]))')
|
|
reClear = None
|
|
andToken = " "
|
|
orToken = " OR "
|
|
notToken = "NOT "
|
|
subExpression = "(%s)"
|
|
listExpression = "(%s)"
|
|
listSeparator = " "
|
|
valueExpression = "\"%s\""
|
|
nullExpression = "NOT %s=\"*\""
|
|
notNullExpression = "%s=\"*\""
|
|
mapExpression = "%s=%s"
|
|
mapListsSpecialHandling = True
|
|
mapListValueExpression = "%s IN %s"
|
|
|
|
def generateMapItemListNode(self, key, value):
|
|
return "(" + (" OR ".join(['%s=%s' % (key, self.generateValueNode(item)) for item in value])) + ")"
|
|
|
|
def generateAggregation(self, agg):
|
|
if agg == None:
|
|
return ""
|
|
if agg.aggfunc == sigma.parser.condition.SigmaAggregationParser.AGGFUNC_NEAR:
|
|
raise NotImplementedError("The 'near' aggregation operator is not yet implemented for this backend")
|
|
if agg.groupfield == None:
|
|
return " | stats %s(%s) as val | search val %s %s" % (agg.aggfunc_notrans, agg.aggfield or "", agg.cond_op, agg.condition)
|
|
else:
|
|
return " | stats %s(%s) as val by %s | search val %s %s" % (agg.aggfunc_notrans, agg.aggfield or "", agg.groupfield or "", agg.cond_op, agg.condition)
|
|
|
|
class SplunkXMLBackend(SingleTextQueryBackend, MultiRuleOutputMixin):
|
|
"""Converts Sigma rule into XML used for Splunk Dashboard Panels"""
|
|
identifier = "splunkxml"
|
|
active = True
|
|
index_field = "index"
|
|
|
|
|
|
panel_pre = "<row><panel><title>"
|
|
panel_inf = "</title><table><search><query>"
|
|
panel_suf = "</query><earliest>$field1.earliest$</earliest><latest>$field1.latest$</latest><sampleRatio>1</sampleRatio>" \
|
|
"</search><option name=\"count\">20</option><option name=\"dataOverlayMode\">none</option><option name=\"" \
|
|
"drilldown\">row</option><option name=\"percentagesRow\">false</option><option name=\"refresh.display\">" \
|
|
"progressbar</option><option name=\"rowNumbers\">false</option><option name=\"totalsRow\">false</option>" \
|
|
"<option name=\"wrap\">true</option></table></panel></row>"
|
|
dash_pre = "<form><label>MyDashboard</label><fieldset submitButton=\"false\"><input type=\"time\" token=\"field1\">" \
|
|
"<label></label><default><earliest>-24h@h</earliest><latest>now</latest></default></input></fieldset>"
|
|
dash_suf = "</form>"
|
|
queries = dash_pre
|
|
|
|
|
|
reEscape = re.compile('("|\\\\(?![*?]))')
|
|
reClear = SplunkBackend.reClear
|
|
andToken = SplunkBackend.andToken
|
|
orToken = SplunkBackend.orToken
|
|
notToken = SplunkBackend.notToken
|
|
subExpression = SplunkBackend.subExpression
|
|
listExpression = SplunkBackend.listExpression
|
|
listSeparator = SplunkBackend.listSeparator
|
|
valueExpression = SplunkBackend.valueExpression
|
|
nullExpression = SplunkBackend.nullExpression
|
|
notNullExpression = SplunkBackend.notNullExpression
|
|
mapExpression = SplunkBackend.mapExpression
|
|
mapListsSpecialHandling = SplunkBackend.mapListsSpecialHandling
|
|
mapListValueExpression = SplunkBackend.mapListValueExpression
|
|
|
|
def generateMapItemListNode(self, key, value):
|
|
return "(" + (" OR ".join(['%s=%s' % (key, self.generateValueNode(item)) for item in value])) + ")"
|
|
|
|
def generateAggregation(self, agg):
|
|
if agg == None:
|
|
return ""
|
|
if agg.aggfunc == sigma.parser.condition.SigmaAggregationParser.AGGFUNC_NEAR:
|
|
return ""
|
|
if agg.groupfield == None:
|
|
return " | stats %s(%s) as val | search val %s %s" % (agg.aggfunc_notrans, agg.aggfield or "", agg.cond_op, agg.condition)
|
|
else:
|
|
return " | stats %s(%s) as val by %s | search val %s %s" % (agg.aggfunc_notrans, agg.aggfield or "", agg.groupfield or "", agg.cond_op, agg.condition)
|
|
|
|
def generate(self, sigmaparser):
|
|
"""Method is called for each sigma rule and receives the parsed rule (SigmaParser)"""
|
|
for parsed in sigmaparser.condparsed:
|
|
query = self.generateQuery(parsed)
|
|
if query is not None:
|
|
self.queries += self.panel_pre
|
|
self.queries += self.getRuleName(sigmaparser)
|
|
self.queries += self.panel_inf
|
|
query = query.replace("<", "<")
|
|
query = query.replace(">", ">")
|
|
self.queries += query
|
|
self.queries += self.panel_suf
|
|
|
|
def finalize(self):
|
|
self.queries += self.dash_suf
|
|
return self.queries
|