[Python-checkins] CVS: python/dist/src/Lib cgi.py,1.63,1.63.2.1

[Anthony Baxter]

Update of /cvsroot/python/python/dist/src/Lib
In directory usw-pr-cvs1:/tmp/cvs-serv12253

Modified Files:
      Tag: release21-maint
	cgi.py 
Log Message:
backport of 1.64, 1.65, 1.68:

1.64: Solve SF bug #231249: cgi.py opens too many (temporary) files.
1.65: Fix a denial-of-service attack, SF bug #443120.
1.68: "ib" should be "boundary"; reported by Neal Norwitz.

the first two of these are pretty severe bugs. 


Index: cgi.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/cgi.py,v
retrieving revision 1.63
retrieving revision 1.63.2.1
diff -C2 -d -r1.63 -r1.63.2.1
*** cgi.py	2001/03/19 13:40:44	1.63
--- cgi.py	2001/12/05 05:10:28	1.63.2.1
***************
*** 29,33 ****
  #
  
! __version__ = "2.5"
  
  
--- 29,33 ----
  #
  
! __version__ = "2.6"
  
  
***************
*** 244,251 ****
  
      """
      if pdict.has_key('boundary'):
          boundary = pdict['boundary']
!     else:
!         boundary = ""
      nextpart = "--" + boundary
      lastpart = "--" + boundary + "--"
--- 244,254 ----
  
      """
+     boundary = ""
      if pdict.has_key('boundary'):
          boundary = pdict['boundary']
!     if not valid_boundary(boundary):
!         raise ValueError,  ('Invalid boundary in multipart form: %s' 
!                             % `boundary`)
!     
      nextpart = "--" + boundary
      lastpart = "--" + boundary + "--"
***************
*** 596,607 ****
      def read_multi(self, environ, keep_blank_values, strict_parsing):
          """Internal: read a part that is itself multipart."""
          self.list = []
          klass = self.FieldStorageClass or self.__class__
!         part = klass(self.fp, {}, self.innerboundary,
                       environ, keep_blank_values, strict_parsing)
          # Throw first part away
          while not part.done:
              headers = rfc822.Message(self.fp)
!             part = klass(self.fp, headers, self.innerboundary,
                           environ, keep_blank_values, strict_parsing)
              self.list.append(part)
--- 599,614 ----
      def read_multi(self, environ, keep_blank_values, strict_parsing):
          """Internal: read a part that is itself multipart."""
+         ib = self.innerboundary
+         if not valid_boundary(ib):
+             raise ValueError, ('Invalid boundary in multipart form: %s' 
+                                % `ib`)
          self.list = []
          klass = self.FieldStorageClass or self.__class__
!         part = klass(self.fp, {}, ib,
                       environ, keep_blank_values, strict_parsing)
          # Throw first part away
          while not part.done:
              headers = rfc822.Message(self.fp)
!             part = klass(self.fp, headers, ib,
                           environ, keep_blank_values, strict_parsing)
              self.list.append(part)
***************
*** 634,638 ****
      def read_lines(self):
          """Internal: read lines until EOF or outerboundary."""
!         self.file = self.make_file('')
          if self.outerboundary:
              self.read_lines_to_outerboundary()
--- 641,645 ----
      def read_lines(self):
          """Internal: read lines until EOF or outerboundary."""
!         self.file = self.__file = StringIO()
          if self.outerboundary:
              self.read_lines_to_outerboundary()
***************
*** 640,643 ****
--- 647,658 ----
              self.read_lines_to_eof()
  
+     def __write(self, line):
+         if self.__file is not None:
+             if self.__file.tell() + len(line) > 1000:
+                 self.file = self.make_file('')
+                 self.file.write(self.__file.getvalue())
+                 self.__file = None
+         self.file.write(line)
+ 
      def read_lines_to_eof(self):
          """Internal: read lines until EOF."""
***************
*** 647,651 ****
                  self.done = -1
                  break
!             self.file.write(line)
  
      def read_lines_to_outerboundary(self):
--- 662,666 ----
                  self.done = -1
                  break
!             self.__write(line)
  
      def read_lines_to_outerboundary(self):
***************
*** 675,679 ****
              else:
                  delim = ""
!             self.file.write(odelim + line)
  
      def skip_lines(self):
--- 690,694 ----
              else:
                  delim = ""
!             self.__write(odelim + line)
  
      def skip_lines(self):
***************
*** 992,995 ****
--- 1007,1013 ----
      return s
  
+ def valid_boundary(s, _vb_pattern="^[ -~]{0,200}[!-~]$"):
+     import re
+     return re.match(_vb_pattern, s)
  
  # Invoke mainline