diff options
Diffstat (limited to 'Lib/poplib.py')
| -rw-r--r-- | Lib/poplib.py | 117 |
1 files changed, 99 insertions, 18 deletions
diff --git a/Lib/poplib.py b/Lib/poplib.py index 43f8305c48..4915628b03 100644 --- a/Lib/poplib.py +++ b/Lib/poplib.py @@ -13,7 +13,15 @@ Based on the J. Myers POP3 draft, Jan. 96 # Imports -import re, socket +import errno +import re +import socket + +try: + import ssl + HAVE_SSL = True +except ImportError: + HAVE_SSL = False __all__ = ["POP3","error_proto"] @@ -33,7 +41,7 @@ LF = b'\n' CRLF = CR+LF # maximal line length when calling readline(). This is to prevent -# reading arbitrary lenght lines. RFC 1939 limits POP3 line length to +# reading arbitrary length lines. RFC 1939 limits POP3 line length to # 512 characters, including CRLF. We have selected 2048 just to be on # the safe side. _MAXLINE = 2048 @@ -61,6 +69,8 @@ class POP3: APOP name digest apop(name, digest) TOP msg n top(msg, n) UIDL [msg] uidl(msg = None) + CAPA capa() + STLS stls() Raises one exception: 'error_proto'. @@ -87,6 +97,7 @@ class POP3: timeout=socket._GLOBAL_DEFAULT_TIMEOUT): self.host = host self.port = port + self._tls_established = False self.sock = self._create_socket(timeout) self.file = self.sock.makefile('rb') self._debugging = 0 @@ -125,7 +136,7 @@ class POP3: # so only possibilities are ...LF, ...CRLF, CR...LF if line[-2:] == CRLF: return line[:-2], octets - if line[0] == CR: + if line[:1] == CR: return line[1:-1], octets return line[:-1], octets @@ -265,11 +276,23 @@ class POP3: def close(self): """Close the connection without assuming anything about it.""" - if self.file is not None: - self.file.close() - if self.sock is not None: - self.sock.close() - self.file = self.sock = None + try: + file = self.file + self.file = None + if file is not None: + file.close() + finally: + sock = self.sock + self.sock = None + if sock is not None: + try: + sock.shutdown(socket.SHUT_RDWR) + except OSError as e: + # The server might already have closed the connection + if e.errno != errno.ENOTCONN: + raise + finally: + sock.close() #__del__ = quit @@ -324,21 +347,71 @@ class POP3: return self._shortcmd('UIDL %s' % which) return self._longcmd('UIDL') -try: - import ssl -except ImportError: - pass -else: + + def capa(self): + """Return server capabilities (RFC 2449) as a dictionary + >>> c=poplib.POP3('localhost') + >>> c.capa() + {'IMPLEMENTATION': ['Cyrus', 'POP3', 'server', 'v2.2.12'], + 'TOP': [], 'LOGIN-DELAY': ['0'], 'AUTH-RESP-CODE': [], + 'EXPIRE': ['NEVER'], 'USER': [], 'STLS': [], 'PIPELINING': [], + 'UIDL': [], 'RESP-CODES': []} + >>> + + Really, according to RFC 2449, the cyrus folks should avoid + having the implementation split into multiple arguments... + """ + def _parsecap(line): + lst = line.decode('ascii').split() + return lst[0], lst[1:] + + caps = {} + try: + resp = self._longcmd('CAPA') + rawcaps = resp[1] + for capline in rawcaps: + capnm, capargs = _parsecap(capline) + caps[capnm] = capargs + except error_proto as _err: + raise error_proto('-ERR CAPA not supported by server') + return caps + + + def stls(self, context=None): + """Start a TLS session on the active connection as specified in RFC 2595. + + context - a ssl.SSLContext + """ + if not HAVE_SSL: + raise error_proto('-ERR TLS support missing') + if self._tls_established: + raise error_proto('-ERR TLS session already established') + caps = self.capa() + if not 'STLS' in caps: + raise error_proto('-ERR STLS not supported by server') + if context is None: + context = ssl._create_stdlib_context() + resp = self._shortcmd('STLS') + self.sock = context.wrap_socket(self.sock, + server_hostname=self.host) + self.file = self.sock.makefile('rb') + self._tls_established = True + return resp + + +if HAVE_SSL: class POP3_SSL(POP3): """POP3 client class over SSL connection - Instantiate with: POP3_SSL(hostname, port=995, keyfile=None, certfile=None) + Instantiate with: POP3_SSL(hostname, port=995, keyfile=None, certfile=None, + context=None) hostname - the hostname of the pop3 over ssl server port - port number keyfile - PEM formatted file that contains your private key certfile - PEM formatted certificate chain file + context - a ssl.SSLContext See the methods of the parent class POP3 for more documentation. """ @@ -353,17 +426,25 @@ else: "exclusive") self.keyfile = keyfile self.certfile = certfile + if context is None: + context = ssl._create_stdlib_context(certfile=certfile, + keyfile=keyfile) self.context = context POP3.__init__(self, host, port, timeout) def _create_socket(self, timeout): sock = POP3._create_socket(self, timeout) - if self.context is not None: - sock = self.context.wrap_socket(sock) - else: - sock = ssl.wrap_socket(sock, self.keyfile, self.certfile) + sock = self.context.wrap_socket(sock, + server_hostname=self.host) return sock + def stls(self, keyfile=None, certfile=None, context=None): + """The method unconditionally raises an exception since the + STLS command doesn't make any sense on an already established + SSL/TLS session. + """ + raise error_proto('-ERR TLS session already established') + __all__.append("POP3_SSL") if __name__ == "__main__": |