cti-python-stix2/stix2/test/test_pattern_expressions.py

380 lines
19 KiB
Python

import datetime
import pytest
import stix2
def test_create_comparison_expression():
exp = stix2.EqualityComparisonExpression("file:hashes.'SHA-256'",
stix2.HashConstant("aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f", "SHA-256")) # noqa
assert str(exp) == "file:hashes.'SHA-256' = 'aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f'"
def test_boolean_expression():
exp1 = stix2.MatchesComparisonExpression("email-message:from_ref.value",
stix2.StringConstant(".+\\@example\\.com$"))
exp2 = stix2.MatchesComparisonExpression("email-message:body_multipart[*].body_raw_ref.name",
stix2.StringConstant("^Final Report.+\\.exe$"))
exp = stix2.AndBooleanExpression([exp1, exp2])
assert str(exp) == "email-message:from_ref.value MATCHES '.+\\\\@example\\\\.com$' AND email-message:body_multipart[*].body_raw_ref.name MATCHES '^Final Report.+\\\\.exe$'" # noqa
def test_boolean_expression_with_parentheses():
exp1 = stix2.MatchesComparisonExpression(stix2.ObjectPath("email-message",
[stix2.ReferenceObjectPathComponent("from_ref"),
stix2.BasicObjectPathComponent("value")]),
stix2.StringConstant(".+\\@example\\.com$"))
exp2 = stix2.MatchesComparisonExpression("email-message:body_multipart[*].body_raw_ref.name",
stix2.StringConstant("^Final Report.+\\.exe$"))
exp = stix2.ParentheticalExpression(stix2.AndBooleanExpression([exp1, exp2]))
assert str(exp) == "(email-message:from_ref.value MATCHES '.+\\\\@example\\\\.com$' AND email-message:body_multipart[*].body_raw_ref.name MATCHES '^Final Report.+\\\\.exe$')" # noqa
def test_hash_followed_by_registryKey_expression_python_constant():
hash_exp = stix2.EqualityComparisonExpression("file:hashes.MD5",
stix2.HashConstant("79054025255fb1a26e4bc422aef54eb4", "MD5"))
o_exp1 = stix2.ObservationExpression(hash_exp)
reg_exp = stix2.EqualityComparisonExpression(stix2.ObjectPath("windows-registry-key", ["key"]),
stix2.StringConstant("HKEY_LOCAL_MACHINE\\foo\\bar"))
o_exp2 = stix2.ObservationExpression(reg_exp)
fb_exp = stix2.FollowedByObservationExpression([o_exp1, o_exp2])
para_exp = stix2.ParentheticalExpression(fb_exp)
qual_exp = stix2.WithinQualifier(300)
exp = stix2.QualifiedObservationExpression(para_exp, qual_exp)
assert str(exp) == "([file:hashes.MD5 = '79054025255fb1a26e4bc422aef54eb4'] FOLLOWEDBY [windows-registry-key:key = 'HKEY_LOCAL_MACHINE\\\\foo\\\\bar']) WITHIN 300 SECONDS" # noqa
def test_hash_followed_by_registryKey_expression():
hash_exp = stix2.EqualityComparisonExpression("file:hashes.MD5",
stix2.HashConstant("79054025255fb1a26e4bc422aef54eb4", "MD5"))
o_exp1 = stix2.ObservationExpression(hash_exp)
reg_exp = stix2.EqualityComparisonExpression(stix2.ObjectPath("windows-registry-key", ["key"]),
stix2.StringConstant("HKEY_LOCAL_MACHINE\\foo\\bar"))
o_exp2 = stix2.ObservationExpression(reg_exp)
fb_exp = stix2.FollowedByObservationExpression([o_exp1, o_exp2])
para_exp = stix2.ParentheticalExpression(fb_exp)
qual_exp = stix2.WithinQualifier(stix2.IntegerConstant(300))
exp = stix2.QualifiedObservationExpression(para_exp, qual_exp)
assert str(exp) == "([file:hashes.MD5 = '79054025255fb1a26e4bc422aef54eb4'] FOLLOWEDBY [windows-registry-key:key = 'HKEY_LOCAL_MACHINE\\\\foo\\\\bar']) WITHIN 300 SECONDS" # noqa
def test_file_observable_expression():
exp1 = stix2.EqualityComparisonExpression("file:hashes.'SHA-256'",
stix2.HashConstant(
"aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f",
'SHA-256'))
exp2 = stix2.EqualityComparisonExpression("file:mime_type", stix2.StringConstant("application/x-pdf"))
bool_exp = stix2.ObservationExpression(stix2.AndBooleanExpression([exp1, exp2]))
assert str(bool_exp) == "[file:hashes.'SHA-256' = 'aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f' AND file:mime_type = 'application/x-pdf']" # noqa
@pytest.mark.parametrize("observation_class, op", [
(stix2.AndObservationExpression, 'AND'),
(stix2.OrObservationExpression, 'OR'),
])
def test_multiple_file_observable_expression(observation_class, op):
exp1 = stix2.EqualityComparisonExpression("file:hashes.'SHA-256'",
stix2.HashConstant(
"bf07a7fbb825fc0aae7bf4a1177b2b31fcf8a3feeaf7092761e18c859ee52a9c",
'SHA-256'))
exp2 = stix2.EqualityComparisonExpression("file:hashes.MD5",
stix2.HashConstant("cead3f77f6cda6ec00f57d76c9a6879f", "MD5"))
bool1_exp = stix2.OrBooleanExpression([exp1, exp2])
exp3 = stix2.EqualityComparisonExpression("file:hashes.'SHA-256'",
stix2.HashConstant(
"aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f",
'SHA-256'))
op1_exp = stix2.ObservationExpression(bool1_exp)
op2_exp = stix2.ObservationExpression(exp3)
exp = observation_class([op1_exp, op2_exp])
assert str(exp) == "[file:hashes.'SHA-256' = 'bf07a7fbb825fc0aae7bf4a1177b2b31fcf8a3feeaf7092761e18c859ee52a9c' OR file:hashes.MD5 = 'cead3f77f6cda6ec00f57d76c9a6879f'] {} [file:hashes.'SHA-256' = 'aec070645fe53ee3b3763059376134f058cc337247c978add178b6ccdfb0019f']".format(op) # noqa
def test_root_types():
ast = stix2.ObservationExpression(
stix2.AndBooleanExpression(
[stix2.ParentheticalExpression(
stix2.OrBooleanExpression([
stix2.EqualityComparisonExpression("a:b", stix2.StringConstant("1")),
stix2.EqualityComparisonExpression("b:c", stix2.StringConstant("2"))])),
stix2.EqualityComparisonExpression(u"b:d", stix2.StringConstant("3"))]))
assert str(ast) == "[(a:b = '1' OR b:c = '2') AND b:d = '3']"
def test_artifact_payload():
exp1 = stix2.EqualityComparisonExpression("artifact:mime_type",
"application/vnd.tcpdump.pcap")
exp2 = stix2.MatchesComparisonExpression("artifact:payload_bin",
stix2.StringConstant("\\xd4\\xc3\\xb2\\xa1\\x02\\x00\\x04\\x00"))
and_exp = stix2.ObservationExpression(stix2.AndBooleanExpression([exp1, exp2]))
assert str(and_exp) == "[artifact:mime_type = 'application/vnd.tcpdump.pcap' AND artifact:payload_bin MATCHES '\\\\xd4\\\\xc3\\\\xb2\\\\xa1\\\\x02\\\\x00\\\\x04\\\\x00']" # noqa
def test_greater_than_python_constant():
exp1 = stix2.GreaterThanComparisonExpression("file:extensions.windows-pebinary-ext.sections[*].entropy", 7.0)
exp = stix2.ObservationExpression(exp1)
assert str(exp) == "[file:extensions.windows-pebinary-ext.sections[*].entropy > 7.0]"
def test_greater_than():
exp1 = stix2.GreaterThanComparisonExpression("file:extensions.windows-pebinary-ext.sections[*].entropy",
stix2.FloatConstant(7.0))
exp = stix2.ObservationExpression(exp1)
assert str(exp) == "[file:extensions.windows-pebinary-ext.sections[*].entropy > 7.0]"
def test_less_than():
exp = stix2.LessThanComparisonExpression("file:size", 1024)
assert str(exp) == "file:size < 1024"
def test_greater_than_or_equal():
exp = stix2.GreaterThanEqualComparisonExpression("file:size",
1024)
assert str(exp) == "file:size >= 1024"
def test_less_than_or_equal():
exp = stix2.LessThanEqualComparisonExpression("file:size",
1024)
assert str(exp) == "file:size <= 1024"
def test_not():
exp = stix2.LessThanComparisonExpression("file:size",
1024,
negated=True)
assert str(exp) == "file:size NOT < 1024"
def test_and_observable_expression():
exp1 = stix2.AndBooleanExpression([stix2.EqualityComparisonExpression("user-account:account_type",
"unix"),
stix2.EqualityComparisonExpression("user-account:user_id",
stix2.StringConstant("1007")),
stix2.EqualityComparisonExpression("user-account:account_login",
"Peter")])
exp2 = stix2.AndBooleanExpression([stix2.EqualityComparisonExpression("user-account:account_type",
"unix"),
stix2.EqualityComparisonExpression("user-account:user_id",
stix2.StringConstant("1008")),
stix2.EqualityComparisonExpression("user-account:account_login",
"Paul")])
exp3 = stix2.AndBooleanExpression([stix2.EqualityComparisonExpression("user-account:account_type",
"unix"),
stix2.EqualityComparisonExpression("user-account:user_id",
stix2.StringConstant("1009")),
stix2.EqualityComparisonExpression("user-account:account_login",
"Mary")])
exp = stix2.AndObservationExpression([stix2.ObservationExpression(exp1),
stix2.ObservationExpression(exp2),
stix2.ObservationExpression(exp3)])
assert str(exp) == "[user-account:account_type = 'unix' AND user-account:user_id = '1007' AND user-account:account_login = 'Peter'] AND [user-account:account_type = 'unix' AND user-account:user_id = '1008' AND user-account:account_login = 'Paul'] AND [user-account:account_type = 'unix' AND user-account:user_id = '1009' AND user-account:account_login = 'Mary']" # noqa
def test_invalid_and_observable_expression():
with pytest.raises(ValueError) as excinfo:
stix2.AndBooleanExpression([stix2.EqualityComparisonExpression("user-account:display_name",
"admin"),
stix2.EqualityComparisonExpression("email-addr:display_name",
stix2.StringConstant("admin"))])
assert "All operands to an 'AND' expression must have the same object type" in str(excinfo)
def test_hex():
exp_and = stix2.AndBooleanExpression([stix2.EqualityComparisonExpression("file:mime_type",
"image/bmp"),
stix2.EqualityComparisonExpression("file:magic_number_hex",
stix2.HexConstant("ffd8"))])
exp = stix2.ObservationExpression(exp_and)
assert str(exp) == "[file:mime_type = 'image/bmp' AND file:magic_number_hex = h'ffd8']"
def test_multiple_qualifiers():
exp_and = stix2.AndBooleanExpression([stix2.EqualityComparisonExpression("network-traffic:dst_ref.type",
"domain-name"),
stix2.EqualityComparisonExpression("network-traffic:dst_ref.value",
"example.com")])
exp_ob = stix2.ObservationExpression(exp_and)
qual_rep = stix2.RepeatQualifier(5)
qual_within = stix2.WithinQualifier(stix2.IntegerConstant(1800))
exp = stix2.QualifiedObservationExpression(stix2.QualifiedObservationExpression(exp_ob, qual_rep), qual_within)
assert str(exp) == "[network-traffic:dst_ref.type = 'domain-name' AND network-traffic:dst_ref.value = 'example.com'] REPEATS 5 TIMES WITHIN 1800 SECONDS" # noqa
def test_set_op():
exp = stix2.ObservationExpression(stix2.IsSubsetComparisonExpression("network-traffic:dst_ref.value",
"2001:0db8:dead:beef:0000:0000:0000:0000/64"))
assert str(exp) == "[network-traffic:dst_ref.value ISSUBSET '2001:0db8:dead:beef:0000:0000:0000:0000/64']"
def test_timestamp():
ts = stix2.TimestampConstant('2014-01-13T07:03:17Z')
assert str(ts) == "t'2014-01-13T07:03:17Z'"
def test_boolean():
exp = stix2.EqualityComparisonExpression("email-message:is_multipart",
True)
assert str(exp) == "email-message:is_multipart = true"
def test_binary():
const = stix2.BinaryConstant("dGhpcyBpcyBhIHRlc3Q=")
exp = stix2.EqualityComparisonExpression("artifact:payload_bin",
const)
assert str(exp) == "artifact:payload_bin = b'dGhpcyBpcyBhIHRlc3Q='"
def test_list():
exp = stix2.InComparisonExpression("process:name",
['proccy', 'proximus', 'badproc'])
assert str(exp) == "process:name IN ('proccy', 'proximus', 'badproc')"
def test_list2():
# alternate way to construct an "IN" Comparison Expression
exp = stix2.EqualityComparisonExpression("process:name",
['proccy', 'proximus', 'badproc'])
assert str(exp) == "process:name IN ('proccy', 'proximus', 'badproc')"
def test_invalid_constant_type():
with pytest.raises(ValueError) as excinfo:
stix2.EqualityComparisonExpression("artifact:payload_bin",
{'foo': 'bar'})
assert 'Unable to create a constant' in str(excinfo)
def test_invalid_integer_constant():
with pytest.raises(ValueError) as excinfo:
stix2.IntegerConstant('foo')
assert 'must be an integer' in str(excinfo)
def test_invalid_timestamp_constant():
with pytest.raises(ValueError) as excinfo:
stix2.TimestampConstant('foo')
assert 'Must be a datetime object or timestamp string' in str(excinfo)
def test_invalid_float_constant():
with pytest.raises(ValueError) as excinfo:
stix2.FloatConstant('foo')
assert 'must be a float' in str(excinfo)
@pytest.mark.parametrize("data, result", [
(True, True),
(False, False),
('True', True),
('False', False),
('true', True),
('false', False),
('t', True),
('f', False),
('T', True),
('F', False),
(1, True),
(0, False),
])
def test_boolean_constant(data, result):
boolean = stix2.BooleanConstant(data)
assert boolean.value == result
def test_invalid_boolean_constant():
with pytest.raises(ValueError) as excinfo:
stix2.BooleanConstant('foo')
assert 'must be a boolean' in str(excinfo)
@pytest.mark.parametrize("hashtype, data", [
('MD5', 'zzz'),
('ssdeep', 'zzz=='),
])
def test_invalid_hash_constant(hashtype, data):
with pytest.raises(ValueError) as excinfo:
stix2.HashConstant(data, hashtype)
assert 'is not a valid {} hash'.format(hashtype) in str(excinfo)
def test_invalid_hex_constant():
with pytest.raises(ValueError) as excinfo:
stix2.HexConstant('mm')
assert "must contain an even number of hexadecimal characters" in str(excinfo)
def test_invalid_binary_constant():
with pytest.raises(ValueError) as excinfo:
stix2.BinaryConstant('foo')
assert 'must contain a base64' in str(excinfo)
def test_escape_quotes_and_backslashes():
exp = stix2.MatchesComparisonExpression("file:name",
"^Final Report.+\\.exe$")
assert str(exp) == "file:name MATCHES '^Final Report.+\\\\.exe$'"
def test_like():
exp = stix2.LikeComparisonExpression("directory:path",
"C:\\Windows\\%\\foo")
assert str(exp) == "directory:path LIKE 'C:\\\\Windows\\\\%\\\\foo'"
def test_issuperset():
exp = stix2.IsSupersetComparisonExpression("ipv4-addr:value",
"198.51.100.0/24")
assert str(exp) == "ipv4-addr:value ISSUPERSET '198.51.100.0/24'"
def test_repeat_qualifier():
qual = stix2.RepeatQualifier(stix2.IntegerConstant(5))
assert str(qual) == 'REPEATS 5 TIMES'
def test_invalid_repeat_qualifier():
with pytest.raises(ValueError) as excinfo:
stix2.RepeatQualifier('foo')
assert 'is not a valid argument for a Repeat Qualifier' in str(excinfo)
def test_invalid_within_qualifier():
with pytest.raises(ValueError) as excinfo:
stix2.WithinQualifier('foo')
assert 'is not a valid argument for a Within Qualifier' in str(excinfo)
def test_startstop_qualifier():
qual = stix2.StartStopQualifier(stix2.TimestampConstant('2016-06-01T00:00:00Z'),
datetime.datetime(2017, 3, 12, 8, 30, 0))
assert str(qual) == "START t'2016-06-01T00:00:00Z' STOP t'2017-03-12T08:30:00Z'"
qual2 = stix2.StartStopQualifier(datetime.date(2016, 6, 1),
stix2.TimestampConstant('2016-07-01T00:00:00Z'))
assert str(qual2) == "START t'2016-06-01T00:00:00Z' STOP t'2016-07-01T00:00:00Z'"
def test_invalid_startstop_qualifier():
with pytest.raises(ValueError) as excinfo:
stix2.StartStopQualifier('foo',
stix2.TimestampConstant('2016-06-01T00:00:00Z'))
assert 'is not a valid argument for a Start/Stop Qualifier' in str(excinfo)
with pytest.raises(ValueError) as excinfo:
stix2.StartStopQualifier(datetime.date(2016, 6, 1),
'foo')
assert 'is not a valid argument for a Start/Stop Qualifier' in str(excinfo)
def test_make_constant_already_a_constant():
str_const = stix2.StringConstant('Foo')
result = stix2.patterns.make_constant(str_const)
assert result is str_const