Important patch for #3459

lib/core/datatype.py

@@ -8,6 +8,8 @@ See the file 'LICENSE' for copying permission
 import copy
 import types
 
+from thirdparty.odict.odict import OrderedDict
+
 class AttribDict(dict):
     """
     This class defines the sqlmap object, inheriting from Python data
@@ -104,3 +106,40 @@ class InjectionDict(AttribDict):
         self.dbms = None
         self.dbms_version = None
         self.os = None
+
+# Reference: https://www.kunxi.org/2014/05/lru-cache-in-python
+class LRUDict(object):
+    def __init__(self, capacity):
+        self.capacity = capacity
+        self.cache = OrderedDict()
+
+    def __len__(self):
+        return len(self.cache)
+
+    def __contains__(self, key):
+        return key in self.cache
+
+    def __getitem__(self, key):
+        try:
+            value = self.cache.pop(key)
+            self.cache[key] = value
+            return value
+        except KeyError:
+            return -1
+
+    def get(self, key):
+        return self.__getitem__(self, key)
+
+    def __setitem__(self, key, value):
+        try:
+            self.cache.pop(key)
+        except KeyError:
+            if len(self.cache) >= self.capacity:
+                self.cache.popitem(last=False)
+        self.cache[key] = value
+
+    def set(self, key, value):
+        self.__setitem__(key, value)
+
+    def keys(self):
+        return self.cache.keys()

lib/core/decorators.py

@@ -7,10 +7,15 @@ See the file 'LICENSE' for copying permission
 
 import functools
 import hashlib
+import threading
 
+from lib.core.settings import MAX_CACHE_ITEMS
+from lib.core.datatype import LRUDict
 from lib.core.threads import getCurrentThreadData
 
-def cachedmethod(f, cache={}):
+_lock = threading.Lock()
+
+def cachedmethod(f, cache=LRUDict(capacity=MAX_CACHE_ITEMS)):
     """
     Method with a cached content
 
@@ -19,11 +24,12 @@ def cachedmethod(f, cache={}):
 
     @functools.wraps(f)
     def _(*args, **kwargs):
-        key = int(hashlib.md5("|".join(str(_) for _ in (f, args, kwargs))).hexdigest(), 16) & 0x7fffffffffffffff
-        if key not in cache:
-            cache[key] = f(*args, **kwargs)
+        with _lock:
+            key = int(hashlib.md5("|".join(str(_) for _ in (f, args, kwargs))).hexdigest(), 16) & 0x7fffffffffffffff
+            if key not in cache:
+                cache[key] = f(*args, **kwargs)
 
-        return cache[key]
+            return cache[key]
 
     return _
 

lib/core/settings.py

@@ -19,7 +19,7 @@ from lib.core.enums import DBMS_DIRECTORY_NAME
 from lib.core.enums import OS
 
 # sqlmap version (<major>.<minor>.<month>.<monthly commit>)
-VERSION = "1.3.1.80"
+VERSION = "1.3.1.81"
 TYPE = "dev" if VERSION.count('.') > 2 and VERSION.split('.')[-1] != '0' else "stable"
 TYPE_COLORS = {"dev": 33, "stable": 90, "pip": 34}
 VERSION_STRING = "sqlmap/%s#%s" % ('.'.join(VERSION.split('.')[:-1]) if VERSION.count('.') > 2 and VERSION.split('.')[-1] == '0' else VERSION, TYPE)
@@ -166,6 +166,9 @@ MAX_TECHNIQUES_PER_VALUE = 2
 # In case of missing piece of partial union dump, buffered array must be flushed after certain size
 MAX_BUFFERED_PARTIAL_UNION_LENGTH = 1024
 
+# Maximum size of cache used in @cachedmethod decorator
+MAX_CACHE_ITEMS = 256
+
 # Suffix used for naming meta databases in DBMS(es) without explicit database name
 METADB_SUFFIX = "_masterdb"