fix: Making yara query an expansion module for single attributes atm

pull/245/head
chrisr3d 4 years ago
parent 1d530a7fa6
commit 1c10fd5e50
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GPG Key ID: 6BBED1B63A6D639F
  1. 32
      misp_modules/modules/expansion/yara_query.py

@ -1,5 +1,5 @@
import json
import sys
import re
misperrors = {'error': 'Error'}
moduleinfo = {'version': '1', 'author': 'Christian STUDER',
@ -7,10 +7,10 @@ moduleinfo = {'version': '1', 'author': 'Christian STUDER',
'module-type': ['expansion', 'hover'],
'require_standard_format': True}
moduleconfig = []
mispattributes = {'input': ['md5', 'sha1', 'sha256', 'filename|md5', 'filename|sha1', 'filename|sha256'], 'output': ['yara rule']}
mispattributes = {'input': ['md5', 'sha1', 'sha256', 'filename|md5', 'filename|sha1', 'filename|sha256'], 'output': ['yara']}
def hash_cond(hashtype, hashvalue):
condition = 'hash.{}(0, filesize) == {}'.format(hashtype, hashvalue.lower())
def get_hash_condition(hashtype, hashvalue):
condition = 'hash.{}(0, filesize) == "{}"'.format(hashtype, hashvalue.lower())
return condition, 'hash'
def handler(q=False):
@ -21,20 +21,16 @@ def handler(q=False):
if 'event_id' in request:
del request['event_id']
uuid = request.pop('attribute_uuid') if 'attribute_uuid' in request else None
rules = []
types = []
for attribute_type, value in request.items():
if 'filename' in attribute_type:
_, attribute_type = attribute_type.split('|')
_, value = value.split('|')
condition, required_module = hash_cond(attribute_type, value)
condition = '\r\n\t\t'.join([condition])
import_section = '\r\n'.join(['import "{}"'.format(required_module)])
rule_start = 'rule %s {' % uuid if uuid else 'rule {'
condition = '\tcondition:\r\n\t\t{}'.format(condition)
rules.append('\r\n'.join([rule_start, condition, '}']))
types.append('yara')
return {'results': [{'types': [t], 'values': [v]} for t, v in zip(types, rules)]}
attribute_type, value = list(request.items())[0]
if 'filename' in attribute_type:
_, attribute_type = attribute_type.split('|')
_, value = value.split('|')
condition, required_module = get_hash_condition(attribute_type, value)
import_section = 'import "{}"'.format(required_module)
rule_start = 'import "hash" \r\nrule %s_%s {' % (attribute_type.upper(), re.sub(r'\W+', '_', uuid)) if uuid else 'import "hash"\r\nrule %s {' % attribute_type.upper()
condition = '\tcondition:\r\n\t\t{}'.format(condition)
rule = '\r\n'.join([rule_start, condition, '}'])
return {'results': [{'types': mispattributes['output'], 'values': [rule]}]}
def introspection():
return mispattributes

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