added Range handler (dealing with 206 HTTP messages)

lib/request/rangehandler.py

@@ -0,0 +1,52 @@
+#!/usr/bin/env python
+
+"""
+$Id$
+
+Copyright (c) 2006-2010 sqlmap developers (http://sqlmap.sourceforge.net/)
+See the file 'doc/COPYING' for copying permission
+"""
+
+import urllib
+import urllib2
+
+from lib.core.exception import sqlmapConnectionException
+
+class HTTPRangeHandler(urllib2.BaseHandler):
+    """
+    Handler that enables HTTP Range headers.
+
+    Reference: http://stackoverflow.com/questions/1971240/python-seek-on-remote-file
+
+    This was extremely simple. The Range header is a HTTP feature to
+    begin with so all this class does is tell urllib2 that the 
+    "206 Partial Content" reponse from the HTTP server is what we 
+    expected.
+
+    Example:
+        import urllib2
+        import byterange
+
+        range_handler = range.HTTPRangeHandler()
+        opener = urllib2.build_opener(range_handler)
+
+        # install it
+        urllib2.install_opener(opener)
+
+        # create Request and set Range header
+        req = urllib2.Request('http://www.python.org/')
+        req.header['Range'] = 'bytes=30-50'
+        f = urllib2.urlopen(req)
+    """
+
+    def http_error_206(self, req, fp, code, msg, hdrs):
+        # 206 Partial Content Response
+        r = urllib.addinfourl(fp, hdrs, req.get_full_url())
+        r.code = code
+        r.msg = msg
+        return r
+
+    def http_error_416(self, req, fp, code, msg, hdrs):
+        # HTTP's Range Not Satisfiable error
+        errMsg = "Invalid range"
+        raise sqlmapConnectionException, errMsg