Added support to directly connect also to Microsoft SQL Server database.

Fixed direct connection to always use the same query as of UNION query SQL injection (= one query with multiple columns/entries output).
Minor fixes to Firebird/Access/SQLite connectors to use connector's execute()/fetchall() as wrapper for third-party libraries' methods.
Forced conf.timeout to 10 seconds when directly connecting to database.
Slightly improved regular expression to parse -d parameter.
Added import check for all connectors' third-party libraries.
Code refactoring:
* Moved conf.direct request to direct() function in lib/request/direct.py (code reused where needed).
* Back-delegated to generic connector close() and other methods.

lib/request/inject.py

@@ -37,6 +37,7 @@ from lib.core.data import logger
 from lib.core.data import queries
 from lib.core.data import temp
 from lib.request.connect import Connect as Request
+from lib.request.direct import direct
 from lib.core.settings import SQL_STATEMENTS
 from lib.techniques.inband.union.use import unionUse
 from lib.techniques.blind.inference import bisection
@@ -352,33 +353,7 @@ def getValue(expression, blind=True, inband=True, fromUser=False, expected=None,
     """
 
     if conf.direct:
-        expression = agent.payloadDirect(expression)
-        values = None
-        select = False
-
-        if kb.dbms == "Oracle" and expression.startswith("SELECT ") and " FROM " not in expression:
-            expression = "%s FROM DUAL" % expression
-
-        for sqlTitle, sqlStatements in SQL_STATEMENTS.items():
-            for sqlStatement in sqlStatements:
-                if expression.lower().startswith(sqlStatement) and sqlTitle == "SQL SELECT statement":
-                    select = True
-                    break
-
-        if select:
-            values = conf.dbmsConnector.select(expression)
-        else:
-            values = conf.dbmsConnector.execute(expression)
-
-        if values is None or len(values) == 0:
-            return None
-        elif len(values) == 1:
-            if len(values[0]) == 1:
-                return str(list(values)[0][0])
-            else:
-                return list(values)
-        else:
-            return values
+        return direct(expression)
 
     expression = cleanQuery(expression)
     expression = expandAsteriskForColumns(expression)
@@ -418,25 +393,7 @@ def goStacked(expression, silent=False):
     expression = cleanQuery(expression)
 
     if conf.direct:
-        expression = agent.payloadDirect(expression)
-        values = None
-        select = False
-
-        if kb.dbms == "Oracle" and expression.startswith("SELECT ") and " FROM " not in expression:
-            expression = "%s FROM DUAL" % expression
-
-        for sqlTitle, sqlStatements in SQL_STATEMENTS.items():
-            for sqlStatement in sqlStatements:
-                if expression.lower().startswith(sqlStatement) and sqlTitle == "SQL SELECT statement":
-                    select = True
-                    break
-
-        if select:
-            values = conf.dbmsConnector.select(expression)
-        else:
-            values = conf.dbmsConnector.execute(expression)
-
-        return None, None
+        return direct(expression), None
 
     debugMsg = "query: %s" % expression
     logger.debug(debugMsg)