# Wrapper module for _ssl. Written by Bill Janssen. # Ported to gevent by Denis Bilenko. """SSL wrapper for socket objects. For the documentation, refer to :mod:`ssl` module manual. This module implements cooperative SSL socket wrappers. On Python 2.6 and older it uses Python's native :mod:`ssl` module. On Python 2.5 and 2.4 it requires `ssl package`_ to be installed. .. __: http://docs.python.org/library/ssl.html .. _`ssl package`: http://pypi.python.org/pypi/ssl """ __ssl__ = __import__('ssl') try: _ssl = __ssl__._ssl except AttributeError: _ssl = __ssl__._ssl2 import sys from gevent.socket import socket, _fileobject, timeout, wait_read, wait_write, timeout_default from gevent.socket import error as socket_error __implements__ = ['SSLObject', 'wrap_socket', 'get_server_certificate', 'sslwrap_simple'] __all__ = ['SSLError', 'CERT_NONE', 'CERT_OPTIONAL', 'CERT_REQUIRED', 'PROTOCOL_SSLv2', 'PROTOCOL_SSLv3', 'PROTOCOL_SSLv23', 'PROTOCOL_TLSv1', 'PROTOCOL_NOSSLv2', 'RAND_status', 'RAND_egd', 'RAND_add', 'SSL_ERROR_ZERO_RETURN', 'SSL_ERROR_WANT_READ', 'SSL_ERROR_WANT_WRITE', 'SSL_ERROR_WANT_X509_LOOKUP', 'SSL_ERROR_SYSCALL', 'SSL_ERROR_SSL', 'SSL_ERROR_WANT_CONNECT', 'SSL_ERROR_EOF', 'SSL_ERROR_INVALID_ERROR_CODE', 'cert_time_to_seconds', 'DER_cert_to_PEM_cert', 'PEM_cert_to_DER_cert', 'get_protocol_name'] for name in __all__: try: value = getattr(__ssl__, name) except AttributeError: continue globals()[name] = value del name, value __all__ += __implements__ class SSLSocket(socket): def __init__(self, sock, keyfile=None, certfile=None, server_side=False, cert_reqs=CERT_NONE, ssl_version=PROTOCOL_SSLv23, ca_certs=None, do_handshake_on_connect=True, suppress_ragged_eofs=True): try: sock = sock._sock except AttributeError: pass socket.__init__(self, _sock=sock) if certfile and not keyfile: keyfile = certfile # see if it's connected try: socket.getpeername(self) except socket_error: # no, no connection yet self._sslobj = None else: # yes, create the SSL object self._sslobj = _ssl.sslwrap(self._sock, server_side, keyfile, certfile, cert_reqs, ssl_version, ca_certs) if do_handshake_on_connect: timeout = self.gettimeout() try: self.settimeout(None) self.do_handshake() finally: self.settimeout(timeout) self.keyfile = keyfile self.certfile = certfile self.cert_reqs = cert_reqs self.ssl_version = ssl_version self.ca_certs = ca_certs self.do_handshake_on_connect = do_handshake_on_connect self.suppress_ragged_eofs = suppress_ragged_eofs self._makefile_refs = 0 def read(self, len=1024): """Read up to LEN bytes and return them. Return zero-length string on EOF.""" while True: try: return self._sslobj.read(len) except SSLError, ex: if ex.args[0] == SSL_ERROR_EOF and self.suppress_ragged_eofs: return '' elif ex.args[0] == SSL_ERROR_WANT_READ: if self.timeout == 0.0: raise sys.exc_clear() wait_read(self.fileno(), timeout=self.timeout) elif ex.args[0] == SSL_ERROR_WANT_WRITE: if self.timeout == 0.0: raise sys.exc_clear() wait_write(self.fileno(), timeout=self.timeout) else: raise def write(self, data): """Write DATA to the underlying SSL channel. Returns number of bytes of DATA actually transmitted.""" while True: try: return self._sslobj.write(data) except SSLError, ex: if ex.args[0] == SSL_ERROR_WANT_READ: if self.timeout == 0.0: raise sys.exc_clear() wait_read(self.fileno(), timeout=self.timeout) elif ex.args[0] == SSL_ERROR_WANT_WRITE: if self.timeout == 0.0: raise sys.exc_clear() wait_write(self.fileno(), timeout=self.timeout) else: raise def getpeercert(self, binary_form=False): """Returns a formatted version of the data in the certificate provided by the other end of the SSL channel. Return None if no certificate was provided, {} if a certificate was provided, but not validated.""" return self._sslobj.peer_certificate(binary_form) def cipher(self): if not self._sslobj: return None else: return self._sslobj.cipher() def send(self, data, flags=0, timeout=timeout_default): if timeout is timeout_default: timeout = self.timeout if self._sslobj: if flags != 0: raise ValueError( "non-zero flags not allowed in calls to send() on %s" % self.__class__) while True: try: v = self._sslobj.write(data) except SSLError, x: if x.args[0] == SSL_ERROR_WANT_READ: if self.timeout == 0.0: raise timeout(str(x)) sys.exc_clear() wait_read(self.fileno(), timeout=timeout) elif x.args[0] == SSL_ERROR_WANT_WRITE: if self.timeout == 0.0: raise timeout(str(x)) sys.exc_clear() wait_write(self.fileno(), timeout=timeout) else: raise else: return v else: return socket.send(self, data, flags, timeout) # is it possible for sendall() to send some data without encryption if another end shut down SSL? def sendto(self, data, addr, flags=0): if self._sslobj: raise ValueError("sendto not allowed on instances of %s" % self.__class__) else: return socket.sendto(self, data, addr, flags) def recv(self, buflen=1024, flags=0): if self._sslobj: if flags != 0: raise ValueError( "non-zero flags not allowed in calls to recv() on %s" % self.__class__) while True: try: return self.read(buflen) except SSLError, x: if x.args[0] == SSL_ERROR_WANT_READ: sys.exc_clear() if self.timeout == 0.0: raise timeout(str(x)) wait_read(self.fileno(), timeout=self.timeout) continue else: raise else: return socket.recv(self, buflen, flags) def recv_into(self, buffer, nbytes=None, flags=0): if buffer and (nbytes is None): nbytes = len(buffer) elif nbytes is None: nbytes = 1024 if self._sslobj: if flags != 0: raise ValueError( "non-zero flags not allowed in calls to recv_into() on %s" % self.__class__) while True: try: tmp_buffer = self.read(nbytes) v = len(tmp_buffer) buffer[:v] = tmp_buffer return v except SSLError, x: if x.args[0] == SSL_ERROR_WANT_READ: sys.exc_clear() if self.timeout == 0.0: raise timeout(str(x)) wait_read(self.fileno(), timeout=self.timeout) continue else: raise else: return socket.recv_into(self, buffer, nbytes, flags) def recvfrom(self, addr, buflen=1024, flags=0): if self._sslobj: raise ValueError("recvfrom not allowed on instances of %s" % self.__class__) else: return socket.recvfrom(self, addr, buflen, flags) def recvfrom_into(self, buffer, nbytes=None, flags=0): if self._sslobj: raise ValueError("recvfrom_into not allowed on instances of %s" % self.__class__) else: return socket.recvfrom_into(self, buffer, nbytes, flags) def pending(self): if self._sslobj: return self._sslobj.pending() else: return 0 def unwrap(self): if self._sslobj: s = self._sslobj.shutdown() self._sslobj = None return socket(_sock=s) else: raise ValueError("No SSL wrapper around " + str(self)) def shutdown(self, how): self._sslobj = None socket.shutdown(self, how) def close(self): if self._makefile_refs < 1: self._sslobj = None socket.close(self) else: self._makefile_refs -= 1 def do_handshake(self): """Perform a TLS/SSL handshake.""" while True: try: return self._sslobj.do_handshake() except SSLError, ex: if ex.args[0] == SSL_ERROR_WANT_READ: if self.timeout == 0.0: raise sys.exc_clear() wait_read(self.fileno(), timeout=self.timeout) elif ex.args[0] == SSL_ERROR_WANT_WRITE: if self.timeout == 0.0: raise sys.exc_clear() wait_write(self.fileno(), timeout=self.timeout) else: raise def connect(self, addr): """Connects to remote ADDR, and then wraps the connection in an SSL channel.""" # Here we assume that the socket is client-side, and not # connected at the time of the call. We connect it, then wrap it. if self._sslobj: raise ValueError("attempt to connect already-connected SSLSocket!") socket.connect(self, addr) self._sslobj = _ssl.sslwrap(self._sock, False, self.keyfile, self.certfile, self.cert_reqs, self.ssl_version, self.ca_certs) if self.do_handshake_on_connect: self.do_handshake() def accept(self): """Accepts a new connection from a remote client, and returns a tuple containing that new connection wrapped with a server-side SSL channel, and the address of the remote client.""" newsock, addr = socket.accept(self) return (SSLSocket(newsock._sock, keyfile=self.keyfile, certfile=self.certfile, server_side=True, cert_reqs=self.cert_reqs, ssl_version=self.ssl_version, ca_certs=self.ca_certs, do_handshake_on_connect=self.do_handshake_on_connect, suppress_ragged_eofs=self.suppress_ragged_eofs), addr) def makefile(self, mode='r', bufsize=-1): """Make and return a file-like object that works with the SSL connection. Just use the code from the socket module.""" self._makefile_refs += 1 return _fileobject(self, mode, bufsize) def wrap_socket(sock, keyfile=None, certfile=None, server_side=False, cert_reqs=CERT_NONE, ssl_version=PROTOCOL_SSLv23, ca_certs=None, do_handshake_on_connect=True, suppress_ragged_eofs=True): return SSLSocket(sock, keyfile=keyfile, certfile=certfile, server_side=server_side, cert_reqs=cert_reqs, ssl_version=ssl_version, ca_certs=ca_certs, do_handshake_on_connect=do_handshake_on_connect, suppress_ragged_eofs=suppress_ragged_eofs) def get_server_certificate (addr, ssl_version=PROTOCOL_SSLv3, ca_certs=None): """Retrieve the certificate from the server at the specified address, and return it as a PEM-encoded string. If 'ca_certs' is specified, validate the server cert against it. If 'ssl_version' is specified, use it in the connection attempt.""" host, port = addr if (ca_certs is not None): cert_reqs = CERT_REQUIRED else: cert_reqs = CERT_NONE s = wrap_socket(socket(), ssl_version=ssl_version, cert_reqs=cert_reqs, ca_certs=ca_certs) s.connect(addr) dercert = s.getpeercert(True) s.close() return DER_cert_to_PEM_cert(dercert) def sslwrap_simple(sock, keyfile=None, certfile=None): """A replacement for the old socket.ssl function. Designed for compability with Python 2.5 and earlier. Will disappear in Python 3.0.""" return SSLSocket(sock, keyfile, certfile)