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956 lines (864 loc) · 30.7 KB
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from sigma.exceptions import SigmaFeatureNotSupportedByBackendError
import pytest
from sigma.backends.splunk import SplunkBackend
from sigma.backends.splunk.splunk import SplunkDeferredORRegularExpression
from sigma.collection import SigmaCollection
from sigma.processing.pipeline import ProcessingPipeline
from sigma.pipelines.splunk import splunk_cim_data_model
@pytest.fixture
def splunk_backend():
return SplunkBackend()
@pytest.fixture
def splunk_custom_backend():
return SplunkBackend(
query_settings=lambda x: {"custom.query.key": x.title},
output_settings={"custom.key": "customvalue"},
)
def test_splunk_and_expression(splunk_backend: SplunkBackend):
rule = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA: valueA
fieldB: valueB
condition: sel
"""
)
assert splunk_backend.convert(rule) == ['fieldA="valueA" fieldB="valueB"']
def test_splunk_or_expression(splunk_backend: SplunkBackend):
rule = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel1:
fieldA: valueA
sel2:
fieldB: valueB
condition: 1 of sel*
"""
)
assert splunk_backend.convert(rule) == ['fieldA="valueA" OR fieldB="valueB"']
def test_splunk_and_or_expression(splunk_backend: SplunkBackend):
rule = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA:
- valueA1
- valueA2
fieldB:
- valueB1
- valueB2
condition: sel
"""
)
assert splunk_backend.convert(rule) == [
'fieldA IN ("valueA1", "valueA2") fieldB IN ("valueB1", "valueB2")'
]
def test_splunk_or_and_expression(splunk_backend: SplunkBackend):
rule = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel1:
fieldA: valueA1
fieldB: valueB1
sel2:
fieldA: valueA2
fieldB: valueB2
condition: 1 of sel*
"""
)
assert splunk_backend.convert(rule) == [
'(fieldA="valueA1" fieldB="valueB1") OR (fieldA="valueA2" fieldB="valueB2")'
]
def test_splunk_in_expression(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA:
- valueA
- valueB
- valueC*
condition: sel
"""
)
)
== ['fieldA IN ("valueA", "valueB", "valueC*")']
)
def test_splunk_field_name_with_whitespace(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
field name: valueA
condition: sel
"""
)
)
== ['"field name"="valueA"']
)
def test_splunk_regex_query(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|re: foo.*bar
fieldB: foo
fieldC: bar
condition: sel
"""
)
)
== ['fieldB="foo" fieldC="bar"\n| regex fieldA="foo.*bar"']
)
def test_splunk_regex_query_implicit_or(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|re:
- foo.*bar
- boo.*foo
fieldB: foo
fieldC: bar
condition: sel
"""
)
)
== [
'\n| rex field=fieldA "(?<fieldAMatch>foo.*bar)"\n| eval fieldACondition=if(isnotnull(fieldAMatch), "true", "false")\n| rex field=fieldA "(?<fieldAMatch2>boo.*foo)"\n| eval fieldACondition2=if(isnotnull(fieldAMatch2), "true", "false")\n| search fieldACondition="true" OR fieldACondition2="true" fieldB="foo" fieldC="bar"'
]
)
def test_splunk_regex_query_explicit_or(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel1:
fieldA|re: foo.*bar
sel2:
fieldB|re: boo.*foo
condition: sel1 or sel2
"""
)
)
== [
'\n| rex field=fieldA "(?<fieldAMatch>foo.*bar)"\n| eval fieldACondition=if(isnotnull(fieldAMatch), "true", "false")\n| rex field=fieldB "(?<fieldBMatch>boo.*foo)"\n| eval fieldBCondition=if(isnotnull(fieldBMatch), "true", "false")\n| search fieldACondition="true" OR fieldBCondition="true"'
]
)
def test_splunk_regex_query_explicit_or_with_nested_fields():
pipeline = ProcessingPipeline.from_yaml(
"""
name: Test
priority: 100
transformations:
- id: field_mapping
type: field_name_mapping
mapping:
fieldA: Event.EventData.fieldA
fieldB: Event.EventData.fieldB
"""
)
splunk_backend = SplunkBackend(pipeline)
collection = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel1:
fieldA|re: foo.*bar
sel2:
fieldB|re: boo.*foo
condition: sel1 or sel2
"""
)
assert splunk_backend.convert(collection) == [
'\n| rex field=Event.EventData.fieldA "(?<fieldAMatch>foo.*bar)"\n| eval fieldACondition=if(isnotnull(fieldAMatch), "true", "false")\n| rex field=Event.EventData.fieldB "(?<fieldBMatch>boo.*foo)"\n| eval fieldBCondition=if(isnotnull(fieldBMatch), "true", "false")\n| search fieldACondition="true" OR fieldBCondition="true"'
]
def test_splunk_regex_query_explicit_or_with_add_condition():
"""Test that conditions added by processing pipelines (index, source) are
placed before deferred rex/eval pipeline commands instead of inside
the trailing '| search' clause."""
pipeline = ProcessingPipeline.from_yaml(
"""
name: Test
priority: 100
transformations:
- id: prefix_source_and_index
type: add_condition
conditions:
index: test
source: test
"""
)
splunk_backend = SplunkBackend(pipeline)
collection = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
selection:
EventID: 4688
CommandLine|re:
- "suspicious_command"
selection2:
Image|re:
- "suspicious_command"
condition: selection or selection2
"""
)
assert splunk_backend.convert(collection) == [
'index="test" source="test"\n| rex field=CommandLine "(?<CommandLineMatch>suspicious_command)"\n| eval CommandLineCondition=if(isnotnull(CommandLineMatch), "true", "false")\n| rex field=Image "(?<ImageMatch>suspicious_command)"\n| eval ImageCondition=if(isnotnull(ImageMatch), "true", "false")\n| search (EventID=4688 CommandLineCondition="true") OR ImageCondition="true"'
]
def test_splunk_regex_group_name_is_capped_for_long_fields():
SplunkDeferredORRegularExpression.reset()
field = "msg_normalized_header_subject"
SplunkDeferredORRegularExpression.add_field(field)
field_match = SplunkDeferredORRegularExpression.get_field_match(field)
assert len(field_match) <= SplunkDeferredORRegularExpression.max_match_group_name_len
assert field_match.endswith("Match")
def test_splunk_regex_group_name_stays_unique_when_truncated():
SplunkDeferredORRegularExpression.reset()
field_1 = "msg_normalized_header_subject_alpha"
field_2 = "msg_normalized_header_subject_bravo"
SplunkDeferredORRegularExpression.add_field(field_1)
SplunkDeferredORRegularExpression.add_field(field_2)
field_match_1 = SplunkDeferredORRegularExpression.get_field_match(field_1)
field_match_2 = SplunkDeferredORRegularExpression.get_field_match(field_2)
assert len(field_match_1) <= SplunkDeferredORRegularExpression.max_match_group_name_len
assert len(field_match_2) <= SplunkDeferredORRegularExpression.max_match_group_name_len
assert field_match_1 != field_match_2
def test_splunk_regex_group_name_keeps_suffix_when_truncated():
SplunkDeferredORRegularExpression.reset()
field = "msg_normalized_header_subject_alpha"
SplunkDeferredORRegularExpression.add_field(field)
SplunkDeferredORRegularExpression.add_field(field)
field_match = SplunkDeferredORRegularExpression.get_field_match(field)
assert len(field_match) <= SplunkDeferredORRegularExpression.max_match_group_name_len
assert field_match.endswith("Match2")
def test_splunk_single_regex_query(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|re: foo.*bar
condition: sel
"""
)
)
== ['*\n| regex fieldA="foo.*bar"']
)
def test_splunk_cidr_query(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|cidr: 192.168.0.0/16
fieldB: foo
fieldC: bar
condition: sel
"""
)
)
== ['fieldA="192.168.0.0/16" fieldB="foo" fieldC="bar"']
)
def test_splunk_cidr_or(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|cidr:
- 192.168.0.0/16
- 10.0.0.0/8
fieldB: foo
fieldC: bar
condition: sel
"""
)
)
== ['fieldA="192.168.0.0/16" OR fieldA="10.0.0.0/8" fieldB="foo" fieldC="bar"']
)
def test_splunk_fieldref_query(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|fieldref: fieldD
fieldB: foo
fieldC: bar
condition: sel
"""
)
)
== ["fieldB=\"foo\" fieldC=\"bar\"\n| where 'fieldA'='fieldD'"]
)
def test_splunk_fieldref_or(splunk_backend: SplunkBackend):
with pytest.raises(SigmaFeatureNotSupportedByBackendError, match="ORing FieldRef"):
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|fieldref:
- fieldD
- fieldE
fieldB: foo
fieldC: bar
condition: sel
"""
)
)
def test_splunk_exists(splunk_backend: SplunkBackend):
assert (
splunk_backend.convert(
SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
detection:
sel:
fieldA|exists: yes
fieldB|exists: no
condition: sel
"""
)
)
== ['fieldA=* NOT fieldB=*']
)
def test_splunk_fields_output(splunk_backend: SplunkBackend):
rule = SigmaCollection.from_yaml(
"""
title: Test
status: test
logsource:
category: test_category
product: test_product
fields:
- fieldA
detection:
sel:
fieldA: valueA
condition: sel
"""
)
assert splunk_backend.convert(rule) == ['fieldA="valueA" | table fieldA']
def test_splunk_savedsearch_output(splunk_backend: SplunkBackend):
rules = """
title: Test 1
description: |
this is a description
across two lines
status: test
logsource:
category: test_category
product: test_product
fields:
- fieldA
detection:
sel:
fieldA|re: foo.*bar
fieldB: foo
fieldC: bar
condition: sel
---
title: Test 2
status: test
logsource:
category: test_category
product: test_product
fields:
- fieldA
- fieldB
detection:
sel:
fieldA: foo
fieldB: bar
condition: sel
"""
assert (
splunk_backend.convert(SigmaCollection.from_yaml(rules), "savedsearches")
== """
[default]
dispatch.earliest_time = -30d
dispatch.latest_time = now
[Test 1]
description = this is a description \\
across two lines
search = fieldB="foo" fieldC="bar" \\
| regex fieldA="foo.*bar" \\
| table fieldA
[Test 2]
description =
search = fieldA="foo" fieldB="bar" \\
| table fieldA,fieldB"""
)
def test_splunk_savedsearch_output_custom(splunk_custom_backend: SplunkBackend):
rules = """
title: Test 1
description: |
this is a description
across two lines
status: test
logsource:
category: test_category
product: test_product
fields:
- fieldA
detection:
sel:
fieldA|re: foo.*bar
fieldB: foo
fieldC: bar
condition: sel
---
title: Test 2
status: test
logsource:
category: test_category
product: test_product
fields:
- fieldA
- fieldB
detection:
sel:
fieldA: foo
fieldB: bar
condition: sel
"""
assert (
splunk_custom_backend.convert(SigmaCollection.from_yaml(rules), "savedsearches")
== """
[default]
dispatch.earliest_time = -30d
dispatch.latest_time = now
custom.key = customvalue
[Test 1]
custom.query.key = Test 1
description = this is a description \\
across two lines
search = fieldB="foo" fieldC="bar" \\
| regex fieldA="foo.*bar" \\
| table fieldA
[Test 2]
custom.query.key = Test 2
description =
search = fieldA="foo" fieldB="bar" \\
| table fieldA,fieldB"""
)
def test_splunk_data_model_process_creation():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: process_creation
product: windows
detection:
sel:
CommandLine: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where
Processes.process="test" by Processes.process Processes.dest Processes.process_current_directory Processes.process_path Processes.process_integrity_level Processes.original_file_name Processes.parent_process
Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id Processes.process_guid Processes.process_id Processes.user
| `drop_dm_object_name(Processes)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_registry_add():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: registry_add
product: windows
detection:
sel:
TargetObject: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where
Registry.registry_key_name="test" by Registry.dest Registry.registry_value_data Registry.action Registry.process_path Registry.process_guid Registry.process_id Registry.registry_key_name
| `drop_dm_object_name(Registry)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_registry_delete():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: registry_delete
product: windows
detection:
sel:
TargetObject: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where
Registry.registry_key_name="test" by Registry.dest Registry.registry_value_data Registry.action Registry.process_path Registry.process_guid Registry.process_id Registry.registry_key_name
| `drop_dm_object_name(Registry)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_registry_event():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: registry_event
product: windows
detection:
sel:
TargetObject: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""
| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where
Registry.registry_key_name="test" by Registry.dest Registry.registry_value_data Registry.action Registry.process_path Registry.process_guid Registry.process_id Registry.registry_key_name
| `drop_dm_object_name(Registry)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", ""
)
]
def test_splunk_data_model_registry_event():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: registry_event
product: windows
detection:
sel:
TargetObject: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where
Registry.registry_key_name="test" by Registry.dest Registry.registry_value_data Registry.action Registry.process_path Registry.process_guid Registry.process_id Registry.registry_key_name
| `drop_dm_object_name(Registry)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_registry_set():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: registry_set
product: windows
detection:
sel:
TargetObject: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Registry where
Registry.registry_key_name="test" by Registry.dest Registry.registry_value_data Registry.action Registry.process_path Registry.process_guid Registry.process_id Registry.registry_key_name
| `drop_dm_object_name(Registry)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_file_event():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: file_event
product: windows
detection:
sel:
TargetFilename: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Filesystem where
Filesystem.file_path="test" by Filesystem.dest Filesystem.file_create_time Filesystem.process_path Filesystem.process_guid Filesystem.process_id Filesystem.file_path
| `drop_dm_object_name(Filesystem)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_process_creation_linux():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: process_creation
product: linux
detection:
sel:
CommandLine: test
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where
Processes.process="test" by Processes.process Processes.dest Processes.process_current_directory Processes.process_path Processes.process_integrity_level Processes.original_file_name Processes.parent_process
Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id Processes.process_guid Processes.process_id Processes.user
| `drop_dm_object_name(Processes)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_dns_query():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: network
service: dns
detection:
sel:
destination.ip: 2001:db8::1
destination.port: 53
dns.id: 1
dns.question.name: example.com
dns.question.type: AAAA
source.ip: 2001:db8::2
source.port: 53
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Network_Resolution.DNS where
DNS.dest="2001:db8::1" DNS.dest_port=53 DNS.transaction_id=1 DNS.query="example.com" DNS.query_type="AAAA" DNS.src="2001:db8::2" DNS.src_port=53
by DNS.dest DNS.dest_port DNS.answer DNS.ttl DNS.record_type DNS.transaction_id DNS.query DNS.query_type DNS.reply_code_id DNS.src DNS.src_port
| `drop_dm_object_name(DNS)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime) """.replace(
"\n", " "
)
]
def test_splunk_data_model_dns_answer():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: network
service: dns
detection:
sel:
destination.ip: 2001:db8::1
destination.port: 53
dns.id: 1
dns.answers.name: cname.example.com
dns.answers.type: CNAME
dns.answers.ttl: 600
source.ip: 2001:db8::2
source.port: 53
condition: sel
"""
assert splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model") == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Network_Resolution.DNS where
DNS.dest="2001:db8::1" DNS.dest_port=53 DNS.transaction_id=1 DNS.answer="cname.example.com" DNS.record_type="CNAME" DNS.ttl=600 DNS.src="2001:db8::2" DNS.src_port=53
by DNS.dest DNS.dest_port DNS.answer DNS.ttl DNS.record_type DNS.transaction_id DNS.query DNS.query_type DNS.reply_code_id DNS.src DNS.src_port
| `drop_dm_object_name(DNS)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime) """.replace(
"\n", " "
)
]
def test_splunk_data_model_process_creation_with_regex():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: process_creation
product: windows
detection:
sel:
ParentImage|endswith: explorer.exe
CommandLine|re: foo.*bar
condition: sel
"""
result = splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model")
assert result == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where
Processes.parent_process_path="*explorer.exe" by Processes.process Processes.dest Processes.process_current_directory Processes.process_path Processes.process_integrity_level Processes.original_file_name Processes.parent_process
Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id Processes.process_guid Processes.process_id Processes.user
| regex Processes.process="foo.*bar"
| `drop_dm_object_name(Processes)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_process_creation_with_or_regex():
splunk_backend = SplunkBackend(processing_pipeline=splunk_cim_data_model())
rule = """
title: Test
status: test
logsource:
category: process_creation
product: windows
detection:
sel_img:
ParentImage|endswith: explorer.exe
sel_cmd:
- CommandLine|contains: test_value
- CommandLine|re: foo.*bar
condition: all of sel_*
"""
result = splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model")
assert result == [
"""| tstats summariesonly=false allow_old_summaries=true fillnull_value="null" count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where
Processes.parent_process_path="*explorer.exe" Processes.process="*test_value*" OR processCondition="true" by Processes.process Processes.dest Processes.process_current_directory Processes.process_path Processes.process_integrity_level Processes.original_file_name Processes.parent_process
Processes.parent_process_path Processes.parent_process_guid Processes.parent_process_id Processes.process_guid Processes.process_id Processes.user
| rex field=Processes.process "(?<processMatch>foo.*bar)"
| eval processCondition=if(isnotnull(processMatch), "true", "false")
| search Processes.parent_process_path="*explorer.exe" Processes.process="*test_value*" OR processCondition="true"
| `drop_dm_object_name(Processes)`
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(firstTime)
| convert timeformat="%Y-%m-%dT%H:%M:%S" ctime(lastTime)
""".replace(
"\n", " "
)
]
def test_splunk_data_model_no_data_model_specified():
splunk_backend = SplunkBackend()
rule = """
title: Test
status: test
logsource:
product: windows
service: security
detection:
sel:
CommandLine: test
condition: sel
"""
with pytest.raises(
SigmaFeatureNotSupportedByBackendError, match="No data model specified"
):
splunk_backend.convert(SigmaCollection.from_yaml(rule), "data_model")