Add a local implementation of httplib.SSLFile and httplib.FakeSocket

Python 2.6 changed its internal implementation which makes it difficult
to override in a way that is backwards compatible.

508953

ipapython/ipasslfile.py

@@ -0,0 +1,179 @@
+# This is a forward backport of the Python2.5 uuid module. It isn't available
+# in Python 2.6
+
+# The next several classes are used to define FakeSocket, a socket-like
+# interface to an SSL connection.
+
+# The primary complexity comes from faking a makefile() method.  The
+# standard socket makefile() implementation calls dup() on the socket
+# file descriptor.  As a consequence, clients can call close() on the
+# parent socket and its makefile children in any order.  The underlying
+# socket isn't closed until they are all closed.
+
+# The implementation uses reference counting to keep the socket open
+# until the last client calls close().  SharedSocket keeps track of
+# the reference counting and SharedSocketClient provides an constructor
+# and close() method that call incref() and decref() correctly.
+
+class SharedSocket:
+    def __init__(self, sock):
+        self.sock = sock
+        self._refcnt = 0
+
+    def incref(self):
+        self._refcnt += 1
+
+    def decref(self):
+        self._refcnt -= 1
+        assert self._refcnt >= 0
+        if self._refcnt == 0:
+            self.sock.close()
+
+    def __del__(self):
+        self.sock.close()
+
+class SharedSocketClient:
+
+    def __init__(self, shared):
+        self._closed = 0
+        self._shared = shared
+        self._shared.incref()
+        self._sock = shared.sock
+
+    def close(self):
+        if not self._closed:
+            self._shared.decref()
+            self._closed = 1
+            self._shared = None
+
+class SSLFile(SharedSocketClient):
+    """File-like object wrapping an SSL socket."""
+
+    BUFSIZE = 8192
+
+    def __init__(self, sock, ssl, bufsize=None):
+        SharedSocketClient.__init__(self, sock)
+        self._ssl = ssl
+        self._buf = ''
+        self._bufsize = bufsize or self.__class__.BUFSIZE
+
+    def _read(self):
+        buf = ''
+        # put in a loop so that we retry on transient errors
+        while True:
+            try:
+                buf = self._ssl.read(self._bufsize)
+            except socket.sslerror, err:
+                if (err[0] == socket.SSL_ERROR_WANT_READ
+                    or err[0] == socket.SSL_ERROR_WANT_WRITE):
+                    continue
+                if (err[0] == socket.SSL_ERROR_ZERO_RETURN
+                    or err[0] == socket.SSL_ERROR_EOF):
+                    break
+                raise
+            except socket.error, err:
+                if err[0] == errno.EINTR:
+                    continue
+                if err[0] == errno.EBADF:
+                    # XXX socket was closed?
+                    break
+                raise
+            else:
+                break
+        return buf
+
+    def read(self, size=None):
+        L = [self._buf]
+        avail = len(self._buf)
+        while size is None or avail < size:
+            s = self._read()
+            if s == '':
+                break
+            L.append(s)
+            avail += len(s)
+        all = "".join(L)
+        if size is None:
+            self._buf = ''
+            return all
+        else:
+            self._buf = all[size:]
+            return all[:size]
+
+    def readline(self):
+        L = [self._buf]
+        self._buf = ''
+        while 1:
+            i = L[-1].find("\n")
+            if i >= 0:
+                break
+            s = self._read()
+            if s == '':
+                break
+            L.append(s)
+        if i == -1:
+            # loop exited because there is no more data
+            return "".join(L)
+        else:
+            all = "".join(L)
+            # XXX could do enough bookkeeping not to do a 2nd search
+            i = all.find("\n") + 1
+            line = all[:i]
+            self._buf = all[i:]
+            return line
+
+    def readlines(self, sizehint=0):
+        total = 0
+        list = []
+        while True:
+            line = self.readline()
+            if not line:
+                break
+            list.append(line)
+            total += len(line)
+            if sizehint and total >= sizehint:
+                break
+        return list
+
+    def fileno(self):
+        return self._sock.fileno()
+
+    def __iter__(self):
+        return self
+
+    def next(self):
+        line = self.readline()
+        if not line:
+            raise StopIteration
+        return line
+
+class FakeSocket(SharedSocketClient):
+
+    class _closedsocket:
+        def __getattr__(self, name):
+            raise error(9, 'Bad file descriptor')
+
+    def __init__(self, sock, ssl):
+        sock = SharedSocket(sock)
+        SharedSocketClient.__init__(self, sock)
+        self._ssl = ssl
+
+    def close(self):
+        SharedSocketClient.close(self)
+        self._sock = self.__class__._closedsocket()
+
+    def makefile(self, mode, bufsize=None):
+        if mode != 'r' and mode != 'rb':
+            raise UnimplementedFileMode()
+        return SSLFile(self._shared, self._ssl, bufsize)
+
+    def send(self, stuff, flags = 0):
+        return self._ssl.write(stuff)
+
+    sendall = send
+
+    def recv(self, len = 1024, flags = 0):
+        return self._ssl.read(len)
+
+    def __getattr__(self, attr):
+        return getattr(self._sock, attr)
+

ipapython/nsslib.py

@@ -27,6 +27,13 @@ import nss.io as io
 import nss.nss as nss
 import nss.ssl as ssl
 
+try:
+    from httplib import SSLFile
+    from httplib import FakeSocket
+except ImportError:
+    from ipapython.ipasslfile import SSLFile
+    from ipapython.ipasslfile import FakeSocket
+
 def client_auth_data_callback(ca_names, chosen_nickname, password, certdb):
     cert = None
     if chosen_nickname:
@@ -49,7 +56,7 @@ def client_auth_data_callback(ca_names, chosen_nickname, password, certdb):
                 return False
         return False
 
-class SSLFile(httplib.SSLFile):
+class SSLFile(SSLFile):
     """
     Override the _read method so we can use the NSS recv method.
     """
@@ -64,7 +71,7 @@ class SSLFile(httplib.SSLFile):
                 break
         return buf
 
-class NSSFakeSocket(httplib.FakeSocket):
+class NSSFakeSocket(FakeSocket):
     def makefile(self, mode, bufsize=None):
         if mode != 'r' and mode != 'rb':
             raise httplib.UnimplementedFileMode()