[tor-commits] [bridgedb/master] Completely rewrite email servers.

commit b11d1c513af7431f473d4443d37e40e1a407aee2 Author: Isis Lovecruft isis@torproject.org Date: Mon May 5 19:15:43 2014 +0000

Completely rewrite email servers.

The old bridgedb.EmailServer module has now been divided into several modules in the bridgedb.email package.

* FIXES #5463 by adding the last touches for email signing.

* FIXES #7547, #7550, and #8241 by adding a welcome email which can be received by sending an invalid request, or by saying "get help" in the body of the email.

* FIXES #11475 by using the same "How To Use Your Bridge Lines" text for TBB/TorLauncher which is used for the HTTP distributor (on the website).

* FIXES #11753 by making email responses translatable. A translated response can be requested, for example, for Farsi, by emailing mailto:bridges+fa@torproject.org. --- lib/bridgedb/EmailServer.py | 483 ------------------------- lib/bridgedb/Main.py | 6 +- lib/bridgedb/email/request.py | 153 ++++++++ lib/bridgedb/email/server.py | 746 +++++++++++++++++++++++++++++++++++++++ lib/bridgedb/email/templates.py | 123 +++++++ setup.py | 1 + 6 files changed, 1026 insertions(+), 486 deletions(-)

diff --git a/lib/bridgedb/EmailServer.py b/lib/bridgedb/EmailServer.py deleted file mode 100644 index 29787ea..0000000 --- a/lib/bridgedb/EmailServer.py +++ /dev/null @@ -1,483 +0,0 @@ -# -*- coding: utf-8 ; test-case-name: bridgedb.test.test_EmailServer -*- -# BridgeDB by Nick Mathewson. -# Copyright (c) 2007-2013, The Tor Project, Inc. -# See LICENSE for licensing information - -"""This module implements the email interface to the bridge database.""" - -from __future__ import unicode_literals - -from email import message -import gettext -import gpgme -import io -import logging -import re -import time - -from ipaddr import IPv4Address -from ipaddr import IPv6Address - -from twisted.internet import defer -from twisted.internet import reactor -from twisted.internet.task import LoopingCall -from twisted.mail import smtp - -from zope.interface import implements - -from bridgedb import Dist -from bridgedb import I18n -from bridgedb import safelog -from bridgedb import translations -from bridgedb.crypto import getGPGContext -from bridgedb.crypto import gpgSignMessage -from bridgedb.crypto import NEW_BUFFER_INTERFACE -from bridgedb.Filters import filterBridgesByIP6 -from bridgedb.Filters import filterBridgesByIP4 -from bridgedb.Filters import filterBridgesByTransport -from bridgedb.Filters import filterBridgesByNotBlockedIn -from bridgedb.parse import addr -from bridgedb.parse.addr import BadEmail -from bridgedb.parse.addr import UnsupportedDomain -from bridgedb.parse.addr import canonicalizeEmailDomain - - -def getBridgeDBEmailAddrFromList(ctx, address_list): - """Loop through a list of (full name, email address) pairs and look up our - mail address. If our address isn't found (which can't happen), return - the default ctx from address so we can keep on working. - """ - email = ctx.fromAddr - for _, address in address_list: - # Strip the @torproject.org part from the address - idx = address.find('@') - if idx != -1: - username = address[:idx] - # See if the user looks familiar. We do a 'find' instead - # of compare because we might have a '+' address here - if username.find(ctx.username) != -1: - email = address - return email - -def getMailResponse(lines, ctx): - """Given a list of lines from an incoming email message, and a - MailContext object, parse the email and decide what to do in response. - If we want to answer, return a 2-tuple containing the address that - will receive the response, and a readable filelike object containing - the response. Return None,None if we shouldn't answer. - """ - raw = io.StringIO() - raw.writelines([unicode('{0}\n'.format(line)) for line in lines]) - raw.seek(0) - - msg = smtp.rfc822.Message(raw) - # Extract data from the headers. - msgID = msg.getheader("Message-ID", None) - subject = msg.getheader("Subject", None) or "[no subject]" - - fromHeader = msg.getaddr("From") - senderHeader = msg.getaddr("Sender") - - clientAddrHeader = None - try: - clientAddrHeader = fromHeader[1] - except (IndexError, TypeError, AttributeError): - pass - - if not clientAddrHeader: - logging.warn("No From header on incoming mail.") - try: - clientAddrHeader = senderHeader[1] - except (IndexError, TypeError, AttributeError): - pass - - if not clientAddrHeader: - logging.warn("No Sender header on incoming mail.") - return None, None - - try: - clientAddr = addr.normalizeEmail(clientAddrHeader, - ctx.cfg.EMAIL_DOMAIN_MAP, - ctx.cfg.EMAIL_DOMAIN_RULES) - except (UnsupportedDomain, BadEmail) as error: - logging.warn(error) - return None, None - - # RFC822 requires at least one 'To' address - clientToList = msg.getaddrlist("To") - clientToAddr = getBridgeDBEmailAddrFromList(ctx, clientToList) - - # Look up the locale part in the 'To:' address, if there is one and get - # the appropriate Translation object - lang = translations.getLocaleFromPlusAddr(clientToAddr) - t = translations.installTranslations(lang) - - canon = ctx.cfg.EMAIL_DOMAIN_MAP - for domain, rule in ctx.cfg.EMAIL_DOMAIN_RULES.items(): - if domain not in canon.keys(): - canon[domain] = domain - for domain in ctx.cfg.EMAIL_DOMAINS: - canon[domain] = domain - - try: - _, clientDomain = addr.extractEmailAddress(clientAddr.lower()) - canonical = canonicalizeEmailDomain(clientDomain, canon) - except (UnsupportedDomain, BadEmail) as error: - logging.warn(error) - return None, None - - rules = ctx.cfg.EMAIL_DOMAIN_RULES.get(canonical, []) - - if 'dkim' in rules: - # getheader() returns the last of a given kind of header; we want - # to get the first, so we use getheaders() instead. - dkimHeaders = msg.getheaders("X-DKIM-Authentication-Results") - dkimHeader = "<no header>" - if dkimHeaders: - dkimHeader = dkimHeaders[0] - if not dkimHeader.startswith("pass"): - logging.info("Rejecting bad DKIM header on incoming email: %r " - % dkimHeader) - return None, None - - # Was the magic string included - #for ln in lines: - # if ln.strip().lower() in ("get bridges", "subject: get bridges"): - # break - #else: - # logging.info("Got a mail from %r with no bridge request; dropping", - # clientAddr) - # return None,None - - # Figure out which bridges to send - unblocked = transport = ipv6 = skippedheaders = False - bridgeFilterRules = [] - addressClass = None - for ln in lines: - # ignore all lines before the subject header - if "subject" in ln.strip().lower(): - skippedheaders = True - if not skippedheaders: - continue - - if "ipv6" in ln.strip().lower(): - ipv6 = True - if "transport" in ln.strip().lower(): - try: - transport = re.search("transport ([_a-zA-Z][_a-zA-Z0-9]*)", - ln).group(1).strip() - except (TypeError, AttributeError): - transport = None - logging.debug("Got request for transport: %s" % transport) - if "unblocked" in ln.strip().lower(): - try: - unblocked = re.search("unblocked ([a-zA-Z]{2,4})", - ln).group(1).strip() - except (TypeError, AttributeError): - transport = None - - if ipv6: - bridgeFilterRules.append(filterBridgesByIP6) - addressClass = IPv6Address - else: - bridgeFilterRules.append(filterBridgesByIP4) - addressClass = IPv4Address - - if transport: - bridgeFilterRules = [filterBridgesByTransport(transport, addressClass)] - - if unblocked: - rules.append(filterBridgesByNotBlockedIn(unblocked, - addressClass, - transport)) - - try: - interval = ctx.schedule.getInterval(time.time()) - bridges = ctx.distributor.getBridgesForEmail(clientAddr, - interval, ctx.N, - countryCode=None, - bridgeFilterRules=bridgeFilterRules) - - # Handle rate limited email - except Dist.TooSoonEmail as err: - logging.info("Got a mail too frequently; warning '%s': %s." - % (clientAddr, err)) - # MAX_EMAIL_RATE is in seconds, convert to hours - body = buildSpamWarningTemplate(t) % (Dist.MAX_EMAIL_RATE / 3600) - return composeEmail(ctx.fromAddr, clientAddr, subject, body, msgID, - gpgContext=ctx.gpgContext) - except Dist.IgnoreEmail as err: - logging.info("Got a mail too frequently; ignoring '%s': %s." - % (clientAddr, err)) - return None, None - except BadEmail as err: - logging.info("Got a mail from a bad email address '%s': %s." - % (clientAddr, err)) - return None, None - - answer = "(no bridges currently available)\n" - if bridges: - with_fp = ctx.cfg.EMAIL_INCLUDE_FINGERPRINTS - answer = "".join(" %s\n" % b.getConfigLine( - includeFingerprint=with_fp, - addressClass=addressClass, - transport=transport, - request=clientAddr) for b in bridges) - - body = buildMessageTemplate(t) % answer - # Generate the message. - return composeEmail(ctx.fromAddr, clientAddr, subject, body, msgID, - gpgContext=ctx.gpgContext) - -def buildMessageTemplate(t): - msg_template = t.gettext(I18n.BRIDGEDB_TEXT[5]) + "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[0]) + "\n\n" \ - + "%s\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[1]) + "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[2]) + "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[3]) + "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[17])+ "\n\n" - # list supported commands, e.g. ipv6, transport - msg_template = msg_template \ - + " " + t.gettext(I18n.BRIDGEDB_TEXT[18])+ "\n" \ - + " " + t.gettext(I18n.BRIDGEDB_TEXT[19])+ "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[6]) + "\n\n" - return msg_template - -def buildSpamWarningTemplate(t): - msg_template = t.gettext(I18n.BRIDGEDB_TEXT[5]) + "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[10]) + "\n\n" \ - + "%s " \ - + t.gettext(I18n.BRIDGEDB_TEXT[11]) + "\n\n" \ - + t.gettext(I18n.BRIDGEDB_TEXT[12]) + "\n\n" - return msg_template - -def _ebReplyToMailFailure(fail): - """Errback for a :api:`twisted.mail.smtp.SMTPSenderFactory`. - - :param fail: A :api:`twisted.python.failure.Failure` which occurred during - the transaction. - """ - logging.debug("EmailServer._ebReplyToMailFailure() called with %r" % fail) - error = fail.getErrorMessage() or "unknown failure." - logging.exception("replyToMail Failure: %s" % error) - return None - -def replyToMail(lines, ctx): - """Reply to an incoming email. Maybe. - - If no `response` is returned from :func:`getMailResponse`, then the - incoming email will not be responded to at all. This can happen for - several reasons, for example: if the DKIM signature was invalid or - missing, or if the incoming email came from an unacceptable domain, or if - there have been too many emails from this client in the allotted time - period. - - :param list lines: A list of lines from an incoming email message. - :type ctx: :class:`MailContext` - :param ctx: The configured context for the email server. - :rtype: :api:`twisted.internet.defer.Deferred` - :returns: A ``Deferred`` which will callback when the response has been - successfully sent, or errback if an error occurred while sending the - email. - """ - logging.info("Got an email; deciding whether to reply.") - sendToUser, response = getMailResponse(lines, ctx) - - d = defer.Deferred() - - if response is None: - logging.debug("We don't feel like talking to %s." % sendToUser) - return d - - response.seek(0) - logging.info("Sending reply to %s" % sendToUser) - factory = smtp.SMTPSenderFactory(ctx.smtpFromAddr, sendToUser, - response, d, retries=0, timeout=30) - d.addErrback(_ebReplyToMailFailure) - reactor.connectTCP(ctx.smtpServer, ctx.smtpPort, factory) - return d - -def composeEmail(fromAddr, clientAddr, subject, body, - msgID=None, gpgContext=None): - - if not subject.startswith("Re:"): - subject = "Re: %s" % subject - - msg = smtp.rfc822.Message(io.StringIO()) - msg.setdefault("From", fromAddr) - msg.setdefault("To", clientAddr) - msg.setdefault("Message-ID", smtp.messageid()) - msg.setdefault("Subject", subject) - if msgID: - msg.setdefault("In-Reply-To", msgID) - msg.setdefault("Date", smtp.rfc822date()) - msg.setdefault('Content-Type', 'text/plain; charset="utf-8"') - headers = [': '.join(m) for m in msg.items()] - - if NEW_BUFFER_INTERFACE: - mail = io.BytesIO() - buff = buffer - else: - mail = io.StringIO() - buff = unicode - - mail.writelines(buff("\r\n".join(headers))) - mail.writelines(buff("\r\n")) - mail.writelines(buff("\r\n")) - - if not gpgContext: - mail.write(buff(body)) - else: - signature, siglist = gpgSignMessage(gpgContext, body) - if signature: - mail.writelines(buff(signature)) - mail.seek(0) - - # Only log the email text (including all headers) if SAFE_LOGGING is - # disabled: - if not safelog.safe_logging: - logging.debug("Email contents:\n\n%s" % mail.read()) - mail.seek(0) - else: - logging.debug("Email text for %r created." % clientAddr) - - return clientAddr, mail - - -class MailContext(object): - """Helper object that holds information used by email subsystem.""" - - def __init__(self, cfg, dist, sched): - # Reject any RCPT TO lines that aren't to this user. - self.username = (cfg.EMAIL_USERNAME or "bridges") - # Reject any mail longer than this. - self.maximumSize = 32*1024 - # Use this server for outgoing mail. - self.smtpServer = (cfg.EMAIL_SMTP_HOST or "127.0.0.1") - self.smtpPort = (cfg.EMAIL_SMTP_PORT or 25) - # Use this address in the MAIL FROM line for outgoing mail. - self.smtpFromAddr = (cfg.EMAIL_SMTP_FROM_ADDR or - "bridges@torproject.org") - # Use this address in the "From:" header for outgoing mail. - self.fromAddr = (cfg.EMAIL_FROM_ADDR or - "bridges@torproject.org") - # An EmailBasedDistributor object - self.distributor = dist - # An IntervalSchedule object - self.schedule = sched - # The number of bridges to send for each email. - self.N = cfg.EMAIL_N_BRIDGES_PER_ANSWER - - # Initialize a gpg context or set to None for backward compatibliity. - self.gpgContext = getGPGContext(cfg) - - self.cfg = cfg - -class MailMessage(object): - """Plugs into the Twisted Mail and receives an incoming message.""" - implements(smtp.IMessage) - - def __init__(self, ctx): - """Create a new MailMessage from a MailContext.""" - self.ctx = ctx - self.lines = [] - self.nBytes = 0 - self.ignoring = False - - def lineReceived(self, line): - """Called when we get another line of an incoming message.""" - self.nBytes += len(line) - if not safelog.safe_logging: - logging.debug("> %s", line.rstrip("\r\n")) - if self.nBytes > self.ctx.maximumSize: - self.ignoring = True - else: - self.lines.append(line) - - def eomReceived(self): - """Called when we receive the end of a message.""" - if not self.ignoring: - replyToMail(self.lines, self.ctx) - return defer.succeed(None) - - def connectionLost(self): - """Called if we die partway through reading a message.""" - pass - -class MailDelivery(object): - """Plugs into Twisted Mail and handles SMTP commands.""" - implements(smtp.IMessageDelivery) - - def setBridgeDBContext(self, ctx): - self.ctx = ctx - - def receivedHeader(self, helo, origin, recipients): - """Create the ``Received:`` header for an incoming email. - - :type helo: tuple - :param helo: The lines received during SMTP client HELO. - :type origin: :api:`twisted.mail.smtp.Address` - :param origin: The email address of the sender. - :type recipients: list - :param recipients: A list of :api:`twisted.mail.smtp.User` instances. - """ - cameFrom = "%s (%s [%s])" % (helo[0] or origin, helo[0], helo[1]) - cameFor = ', '.join(["<{0}>".format(recp.dest) for recp in recipients]) - hdr = str("Received: from %s for %s; %s" % (cameFrom, cameFor, - smtp.rfc822date())) - return hdr - - def validateFrom(self, helo, origin): - return origin - - def validateTo(self, user): - """If the local user that was addressed isn't our configured local user - or doesn't contain a '+' with a prefix matching the local configured - user: Yell. - """ - u = user.dest.local - # Hasplus? If yes, strip '+foo' - idx = u.find('+') - if idx != -1: - u = u[:idx] - if u != self.ctx.username: - raise smtp.SMTPBadRcpt(user) - return lambda: MailMessage(self.ctx) - -class MailFactory(smtp.SMTPFactory): - """Plugs into Twisted Mail; creates a new MailDelivery whenever we get - a connection on the SMTP port.""" - - def __init__(self, *a, **kw): - smtp.SMTPFactory.__init__(self, *a, **kw) - self.delivery = MailDelivery() - - def setBridgeDBContext(self, ctx): - self.ctx = ctx - self.delivery.setBridgeDBContext(ctx) - - def buildProtocol(self, addr): - p = smtp.SMTPFactory.buildProtocol(self, addr) - p.delivery = self.delivery - return p - -def addSMTPServer(cfg, dist, sched): - """Set up a smtp server. - cfg -- a configuration object from Main. We use these options: - EMAIL_BIND_IP - EMAIL_PORT - EMAIL_N_BRIDGES_PER_ANSWER - EMAIL_DOMAIN_RULES - dist -- an EmailBasedDistributor object. - sched -- an IntervalSchedule object. - """ - ctx = MailContext(cfg, dist, sched) - factory = MailFactory() - factory.setBridgeDBContext(ctx) - ip = cfg.EMAIL_BIND_IP or "" - reactor.listenTCP(cfg.EMAIL_PORT, factory, interface=ip) - # Set up a LoopingCall to run every 30 minutes and forget old email times. - lc = LoopingCall(dist.cleanDatabase) - lc.start(1800, now=False) - return factory diff --git a/lib/bridgedb/Main.py b/lib/bridgedb/Main.py index 90a03ef..1b4420e 100644 --- a/lib/bridgedb/Main.py +++ b/lib/bridgedb/Main.py @@ -443,7 +443,7 @@ def startup(options):

state = persistent.State(config=config)

- from bridgedb import EmailServer + from bridgedb.email.server import addServer as addSMTPServer from bridgedb import HTTPServer

# Load the master key, or create a new one. @@ -596,7 +596,7 @@ def startup(options): if config.EMAIL_DIST and config.EMAIL_SHARE: #emailSchedule = Time.IntervalSchedule("day", 1) emailSchedule = Time.NoSchedule() - EmailServer.addSMTPServer(config, emailDistributor, emailSchedule) + addSMTPServer(config, emailDistributor, emailSchedule)

# Actually run the servers. try: @@ -623,7 +623,7 @@ def runSubcommand(options, config): """ # Make sure that the runner module is only imported after logging is set # up, otherwise we run into the same logging configuration problem as - # mentioned above with the EmailServer and HTTPServer. + # mentioned above with the email.server and HTTPServer. from bridgedb import runner

statuscode = 0 diff --git a/lib/bridgedb/email/__init__.py b/lib/bridgedb/email/__init__.py new file mode 100644 index 0000000..e69de29 diff --git a/lib/bridgedb/email/request.py b/lib/bridgedb/email/request.py new file mode 100644 index 0000000..e5b1fb9 --- /dev/null +++ b/lib/bridgedb/email/request.py @@ -0,0 +1,153 @@ +# -*- coding: utf-8 -*- + +from __future__ import print_function +from __future__ import unicode_literals + +import logging +import re + +from bridgedb import bridgerequest +from bridgedb.Dist import EmailRequestedHelp +from bridgedb.Dist import EmailRequestedKey + + +#: A regular expression for matching the Pluggable Transport method TYPE in +#: emailed requests for Pluggable Transports. +TRANSPORT_REGEXP = ".*transport ([a-z][_a-z0-9]*)" +TRANSPORT_PATTERN = re.compile(TRANSPORT_REGEXP) + +#: A regular expression that matches country codes in requests for unblocked +#: bridges. +UNBLOCKED_REGEXP = ".*unblocked ([a-z]{2,4})" +UNBLOCKED_PATTERN = re.compile(UNBLOCKED_REGEXP) + + +def determineBridgeRequestOptions(lines): + """Figure out which :class:`Bridges.BridgeFilter`s to apply, or offer help. + + .. note:: If any ``'transport TYPE'`` was requested, or bridges not + blocked in a specific CC (``'unblocked CC'``), then the ``TYPE`` + and/or ``CC`` will *always* be stored as a *lowercase* string. + + :param list lines: A list of lines from an email, including the headers. + :raises EmailRequestedHelp: if the client requested help. + :raises EmailRequestedKey: if the client requested our GnuPG key. + :rtype: :class:`EmailBridgeRequest` + :returns: A :class:`~bridgerequst.BridgeRequest` with all of the requested + parameters set. The returned ``BridgeRequest`` will have already had + its filters generated via :meth:`~EmailBridgeRequest.generateFilters`. + """ + request = EmailBridgeRequest() + skippedHeaders = False + + for line in lines: + line = line.strip().lower() + # Ignore all lines before the first empty line: + if not line: skippedHeaders = True + if not skippedHeaders: continue + + if ("help" in line) or ("halp" in line): + raise EmailRequestedHelp("Client requested help.") + + if "get" in line: + request.isValid(True) + logging.debug("Email request was valid.") + if "key" in line: + request.wantsKey(True) + raise EmailRequestedKey("Email requested a copy of our GnuPG key.") + if "ipv6" in line: + request.withIPv6() + if "transport" in line: + request.withPluggableTransportType(line) + if "unblocked" in line: + request.withoutBlockInCountry(line) + + logging.debug("Generating hashring filters for request.") + request.generateFilters() + return request + + +class EmailBridgeRequest(bridgerequest.BridgeRequestBase): + """We received a request for bridges through the email distributor.""" + + def __init__(self): + """Process a new bridge request received through the + :class:`~bridgedb.Dist.EmailBasedDistributor`. + """ + super(EmailBridgeRequest, self).__init__() + self._isValid = False + self._wantsKey = False + + def isValid(self, valid=None): + """Get or set the validity of this bridge request. + + If called without parameters, this method will return the current + state, otherwise (if called with the **valid** parameter), it will set + the current state of validity for this request. + + :param bool valid: If given, set the validity state of this + request. Otherwise, get the current state. + """ + if valid is not None: + self._isValid = bool(valid) + return self._isValid + + def wantsKey(self, wantsKey=None): + """Get or set whether this bridge request wanted our GnuPG key. + + If called without parameters, this method will return the current + state, otherwise (if called with the **wantsKey** parameter set), it + will set the current state for whether or not this request wanted our + key. + + :param bool wantsKey: If given, set the validity state of this + request. Otherwise, get the current state. + """ + if wantsKey is not None: + self._wantsKey = bool(wantsKey) + return self._wantsKey + + def withoutBlockInCountry(self, line): + """This request was for bridges not blocked in **country**. + + Add any country code found in the **line** to the list of + ``notBlockedIn``. Currently, a request for a transport is recognized + if the email line contains the ``'unblocked'`` command. + + :param str country: The line from the email wherein the client + requested some type of Pluggable Transport. + """ + unblocked = None + + logging.debug("Parsing 'unblocked' line: %r" % line) + try: + unblocked = UNBLOCKED_PATTERN.match(line).group(1) + except (TypeError, AttributeError): + pass + + if unblocked: + self.notBlockedIn.append(unblocked) + logging.info("Email requested bridges not blocked in: %r" + % unblocked) + + def withPluggableTransportType(self, line): + """This request included a specific Pluggable Transport identifier. + + Add any Pluggable Transport method TYPE found in the **line** to the + list of ``transports``. Currently, a request for a transport is + recognized if the email line contains the ``'transport'`` command. + + :param str line: The line from the email wherein the client + requested some type of Pluggable Transport. + """ + transport = None + logging.debug("Parsing 'transport' line: %r" % line) + + try: + transport = TRANSPORT_PATTERN.match(line).group(1) + except (TypeError, AttributeError): + pass + + if transport: + self.transports.append(transport) + logging.info("Email requested transport type: %r" % transport) diff --git a/lib/bridgedb/email/server.py b/lib/bridgedb/email/server.py new file mode 100644 index 0000000..97ddcde --- /dev/null +++ b/lib/bridgedb/email/server.py @@ -0,0 +1,746 @@ +# -*- coding: utf-8 ; test-case-name: bridgedb.test.test_email_server -*- +#_____________________________________________________________________________ +# +# This file is part of BridgeDB, a Tor bridge distribution system. +# +# :authors: Nick Mathewson nickm@torproject.org +# Isis Lovecruft isis@torproject.org 0xA3ADB67A2CDB8B35 +# Matthew Finkel sysrqb@torproject.org +# please also see AUTHORS file +# :copyright: (c) 2007-2014, The Tor Project, Inc. +# (c) 2013-2014, Isis Lovecruft +# :license: see LICENSE for licensing information +#_____________________________________________________________________________ + + +"""Servers which interface with clients and distribute bridges over SMTP.""" + +from __future__ import unicode_literals + +import logging +import io +import time + +from twisted.internet import defer +from twisted.internet import reactor +from twisted.internet.task import LoopingCall +from twisted.mail import smtp + +from zope.interface import implements + +from bridgedb import safelog +from bridgedb import translations +from bridgedb.crypto import getGPGContext +from bridgedb.crypto import gpgSignMessage +from bridgedb.crypto import NEW_BUFFER_INTERFACE +from bridgedb.Dist import EmailRequestedHelp +from bridgedb.Dist import EmailRequestedKey +from bridgedb.Dist import TooSoonEmail +from bridgedb.Dist import IgnoreEmail +from bridgedb.email import templates +from bridgedb.email import request +from bridgedb.parse import addr +from bridgedb.parse.addr import BadEmail +from bridgedb.parse.addr import UnsupportedDomain +from bridgedb.parse.addr import canonicalizeEmailDomain + + +def checkDKIM(message, rules): + """Check the DKIM verification results header. + + This check is only run if the incoming email, **message**, originated from + a domain for which we're configured (in the ``EMAIL_DOMAIN_RULES`` + dictionary in the config file) to check DKIM verification results for. + + :type message: :api:`twisted.mail.smtp.rfc822.Message` + :param message: The incoming client request email, including headers. + :param dict rules: The list of configured ``EMAIL_DOMAIN_RULES`` for the + canonical domain which the client's email request originated from. + + :rtype: bool + :returns: ``False`` if: + 1. We're supposed to expect and check the DKIM headers for the + client's email provider domain. + 2. Those headers were *not* okay. + Otherwise, returns ``True``. + """ + if 'dkim' in rules: + # getheader() returns the last of a given kind of header; we want + # to get the first, so we use getheaders() instead. + dkimHeaders = message.getheaders("X-DKIM-Authentication-Results") + dkimHeader = "<no header>" + if dkimHeaders: + dkimHeader = dkimHeaders[0] + if not dkimHeader.startswith("pass"): + logging.info("Rejecting bad DKIM header on incoming email: %r " + % dkimHeader) + return False + return True + +def createResponseBody(lines, context, toAddress, lang='en'): + """Parse the **lines** from an incoming email request and determine how to + respond. + + :param list lines: The list of lines from the original request sent by the + client. + :type context: class:`MailContext` + :param context: The context which contains settings for the email server. + :param str toAddress: The rfc:`2821` email address which should be in the + :header:`To:` header of the response email. + :param str lang: The 2-5 character locale code to use for translating the + email. This is obtained from a client sending a email to a valid plus + address which includes the translation desired, i.e. by sending an + email to ``bridges+fa@torproject.org``, the client should receive a + response in Farsi. + :rtype: None or str + :returns: None if we shouldn't respond to the client (i.e., if they have + already received a rate-limiting warning email). Otherwise, returns a + string containing the (optionally translated) body for the email + response which we should send out. + """ + t = translations.installTranslations(lang) + + bridges = None + try: + bridgeRequest = request.determineBridgeRequestOptions(lines) + + # The request was invalid, respond with a help email which explains + # valid email commands: + if not bridgeRequest.isValid(): + raise EmailRequestedHelp("Email request from %r was invalid." + % toAddress) + + # Otherwise they must have requested bridges: + interval = context.schedule.getInterval(time.time()) + bridges = context.distributor.getBridgesForEmail( + toAddress, + interval, + context.nBridges, + countryCode=None, + bridgeFilterRules=bridgeRequest.filters) + except EmailRequestedHelp as error: + logging.info(error) + return templates.buildWelcomeText(t) + except EmailRequestedKey as error: + logging.info(error) + return templates.buildKeyfile(t) + except TooSoonEmail as error: + logging.info("Got a mail too frequently: %s." % error) + return templates.buildSpamWarning(t) + except (IgnoreEmail, BadEmail) as error: + logging.info(error) + # Don't generate a response if their email address is unparsable or + # invalid, or if we've already warned them about rate-limiting: + return None + else: + answer = "(no bridges currently available)\r\n" + if bridges: + transport = bridgeRequest.justOnePTType() + answer = "".join(" %s\r\n" % b.getConfigLine( + includeFingerprint=context.includeFingerprints, + addressClass=bridgeRequest.addressClass, + transport=transport, + request=toAddress) for b in bridges) + return templates.buildMessage(t) % answer + +def generateResponse(fromAddress, clientAddress, subject, body, + messageID=None, gpgContext=None): + """Create a :class:`MailResponse`, which acts like an in-memory + ``io.StringIO`` file, by creating and writing all headers and the email + body into the file-like ``MailResponse.mailfile``. + + :param str fromAddress: The rfc:`2821` email address which should be in + the :header:`From:` header. + :param str clientAddress: The rfc:`2821` email address which should be in + the :header:`To:` header. + :param str subject: The string to write to the :header:`subject` header. + :param str body: The body of the email. If a **gpgContext** is also given, + and that ``Context`` has email signing configured, then + :meth:`MailResponse.writeBody` will generate and include any + ascii-armored OpenPGP signatures in the **body**. + :type messageID: None or str + :param messageID: The :rfc:`2822` specifier for the :header:`Message-ID:` + header, if including one is desirable. + :type gpgContext: None or ``gpgme.Context``. + :param gpgContext: A pre-configured GPGME context. See + :meth:`~crypto.getGPGContext`. + :rtype: :class:`MailResponse` + :returns: A ``MailResponse`` which contains the entire email. To obtain + the contents of the email, including all headers, simply use + :meth:`MailResponse.read`. + """ + response = MailResponse(gpgContext) + response.writeHeaders(fromAddress, clientAddress, subject, + inReplyTo=messageID) + response.writeBody(body) + + # Only log the email text (including all headers) if SAFE_LOGGING is + # disabled: + if not safelog.safe_logging: + contents = response.readContents() + logging.debug("Email contents:\n%s" % contents) + else: + logging.debug("Email text for %r created." % clientAddress) + response.rewind() + return response + + +class MailContext(object): + """Helper object that holds information used by email subsystem.""" + + def __init__(self, config, distributor, schedule): + """DOCDOC + + :ivar str username: Reject any RCPT TO lines that aren't to this + user. See the ``EMAIL_USERNAME`` option in the config file. + (default: ``'bridges'``) + :ivar int maximumSize: Reject any incoming emails longer than + this size (in bytes). (default: 3084 bytes). + :ivar int smtpPort: The port to use for outgoing SMTP. + :ivar str smtpServer: The IP address to use for outgoing SMTP. + :ivar str smtpFromAddr: Use this address in the raw SMTP ``MAIL FROM`` + line for outgoing mail. (default: ``bridges@torproject.org``) + :ivar str fromAddr: Use this address in the email :header:`From:` + line for outgoing mail. (default: ``bridges@torproject.org``) + :ivar int nBridges: The number of bridges to send for each email. + :ivar gpgContext: A ``gpgme.GpgmeContext`` (as created by + :func:`bridgedb.crypto.getGPGContext`), or None if we couldn't + create a proper GPGME context for some reason. + + :type config: :class:`bridgedb.persistent.Conf` + :type distributor: :class:`bridgedb.Dist.EmailBasedDistributor`. + :param distributor: DOCDOC + :type schedule: :class:`bridgedb.Time.IntervalSchedule`. + :param schedule: DOCDOC + """ + self.config = config + self.distributor = distributor + self.schedule = schedule + + self.maximumSize = 32*1024 + self.includeFingerprints = config.EMAIL_INCLUDE_FINGERPRINTS + self.nBridges = config.EMAIL_N_BRIDGES_PER_ANSWER + + self.username = (config.EMAIL_USERNAME or "bridges") + self.fromAddr = (config.EMAIL_FROM_ADDR or "bridges@torproject.org") + self.smtpFromAddr = (config.EMAIL_SMTP_FROM_ADDR or self.fromAddr) + self.smtpServerPort = (config.EMAIL_SMTP_PORT or 25) + self.smtpServerIP = (config.EMAIL_SMTP_HOST or "127.0.0.1") + + self.domainRules = config.EMAIL_DOMAIN_RULES or {} + self.domainMap = config.EMAIL_DOMAIN_MAP or {} + self.canon = self.buildCanonicalDomainMap() + + self.gpgContext = getGPGContext(config) + + def buildCanonicalDomainMap(self): + """Build a map for all email provider domains from which we will accept + emails to their canonical domain name. + + .. note:: Be sure that ``MailContext.domainRules`` and + ``MailContext.domainMap`` are set appropriately before calling + this method. + + This method is automatically called during initialisation, and the + resulting domain map is stored as ``MailContext.canon``. + + :rtype: dict + :returns: A dictionary which maps all domains and subdomains which we + accept emails from to their second-level, canonical domain names. + """ + canon = self.domainMap + for domain, rule in self.domainRules.items(): + if domain not in canon.keys(): + canon[domain] = domain + for domain in self.config.EMAIL_DOMAINS: + canon[domain] = domain + return canon + + +class MailResponse(object): + """Holds information for generating a response email for a request. + + .. todo:: At some point, we may want to change this class to optionally + handle creating Multipart MIME encoding messages, so that we can + include attachments. (This would be useful for attaching our GnuPG + keyfile, for example, rather than simply pasting it into the body of + the email.) + + :type _buff: unicode or buffer + :cvar _buff: Used internally to write lines for the response email into + the ``_mailfile``. The reason why both of these attributes have two + possible types is for the same Python-buggy reasons which require + :data:`~bridgedb.crypto.NEW_BUFFER_INTERFACE`. + :type mailfile: :class:`io.StringIO` or :class:`io.BytesIO`. + :cvar mailfile: An in-memory file for storing the formatted headers and + body of the response email. + """ + + implements(smtp.IMessage) + + _buff = buffer if NEW_BUFFER_INTERFACE else unicode + mailfile = io.BytesIO if NEW_BUFFER_INTERFACE else io.StringIO + + def __init__(self, gpgContext=None): + """Create a response to an email we have recieved. + + This class deals with correctly formatting text for the response email + headers and the response body into an instance of :cvar:`mailfile`. + + :type gpgContext: None or ``gpgme.Context`` + :param gpgContext: A pre-configured GPGME context. See + :meth:`bridgedb.crypto.getGPGContext` for obtaining a + pre-configured **gpgContext**. If given, and the ``Context`` has + been configured to sign emails, then a response email body string + given to :meth:`writeBody` will be signed before being written + into the ``mailfile``. + """ + self.gpgContext = gpgContext + self.mailfile = self.mailfile() + self.closed = False + + # These are methods and attributes for controlling I/O operations on our + # underlying ``mailfile``. + + def close(self): + self.mailfile.close() + self.closed = True + close.__doc__ = mailfile.close.__doc__ + + def flush(self, *args, **kwargs): self.mailfile.flush(*args, **kwargs) + flush.__doc__ = mailfile.flush.__doc__ + + def read(self, *args, **kwargs): + self.mailfile.read(*args, **kwargs) + read.__doc__ = mailfile.read.__doc__ + + def readline(self, *args, **kwargs): + self.mailfile.readline(*args, **kwargs) + readline.__doc__ = mailfile.readline.__doc__ + + def readlines(self, *args, **kwargs): + self.mailfile.readlines(*args, **kwargs) + readlines.__doc__ = mailfile.readlines.__doc__ + + def seek(self, *args, **kwargs): + self.mailfile.seek(*args, **kwargs) + seek.__doc__ = mailfile.seek.__doc__ + + def tell(self, *args, **kwargs): + self.mailfile.tell(*args, **kwargs) + tell.__doc__ = mailfile.tell.__doc__ + + def truncate(self, *args, **kwargs): + self.mailfile.truncate(*args, **kwargs) + truncate.__doc__ = mailfile.truncate.__doc__ + + # The following are custom methods to control reading and writing to the + # underlying ``mailfile``. + + def readContents(self): + """Read the all the contents written thus far to the :cvar:`mailfile`, + and then :meth:`seek` to return to the original pointer position we + were at before this method was called. + + :rtype: str + :returns: The entire contents of the :cvar:`mailfile`. + """ + pointer = self.mailfile.tell() + self.mailfile.seek(0) + contents = self.mailfile.read() + self.mailfile.seek(pointer) + return contents + + def rewind(self): + """Rewind to the very beginning of the :cvar:`mailfile`.""" + self.seek(0) + + def write(self, line): + """Any **line** written to me will have ``'\r\n'`` appended to it.""" + self.mailfile.write(self._buff(line + '\r\n')) + self.mailfile.flush() + + def writelines(self, lines): + """Calls :meth:`write` for each line in **lines**.""" + if isinstance(lines, basestring): + for ln in lines.split('\n'): + self.write(ln) + elif isinstance(lines, (list, tuple,)): + for ln in lines: + self.write(ln) + + def writeHeaders(self, fromAddress, toAddress, subject=None, + inReplyTo=None, includeMessageID=True, + contentType='text/plain; charset="utf-8"', **kwargs): + """Write all headers into the response email. + + :param str fromAddress: The email address for the ``From:`` header. + :param str toAddress: The email address for the ``To:`` header. + :type subject: None or str + :param subject: The ``Subject:`` header. + :type inReplyTo: None or str + :param inReplyTo: If set, an ``In-Reply-To:`` header will be + generated. This should be set to the ``Message-ID:`` header from + the client's original request email. + :param bool includeMessageID: If ``True``, generate and include a + ``Message-ID:`` header for the response. + :param str contentType: The ``Content-Type:`` header. + :kwargs: If given, the key will become the name of the header, and the + value will become the Contents of that header. + """ + self.write("From: %s" % fromAddress) + self.write("To: %s" % toAddress) + if includeMessageID: + self.write("Message-ID: %s" % smtp.messageid()) + if inReplyTo: + self.write("In-Reply-To: %s" % inReplyTo) + self.write("Content-Type: %s" % contentType) + self.write("Date: %s" % smtp.rfc822date()) + + if not subject: + subject = '[no subject]' + if not subject.lower().startswith('re'): + subject = "Re: " + subject + self.write("Subject: %s" % subject) + + if kwargs: + for headerName, headerValue in kwargs.items(): + headerName = headerName.capitalize() + headerName = headerName.replace(' ', '-') + headerName = headerName.replace('_', '-') + self.write("%s: %s" % (headerName, headerValue)) + + # The first blank line designates that the headers have ended: + self.write("\r\n") + + def writeBody(self, body): + """Write the response body into the :cvar:`mailfile`. + + If ``MailResponse.gpgContext`` is set, and signing is configured, the + **body** will be automatically signed before writing its contents into + the ``mailfile``. + + :param str body: The body of the response email. + """ + if self.gpgContext: + body, _ = gpgSignMessage(self.gpgContext, body) + self.writelines(body) + + # The following methods implement the IMessage interface. + + def lineReceived(self, line): + """Called when we receive a line from an underlying transport.""" + self.write(line) + + def eomRecieved(self): + """Called when we receive an EOM. + + :rtype: :api:`twisted.internet.defer.Deferred` + :returns: A ``Deferred`` which has already been callbacked with the + entire response email contents retrieved from + :meth:`readContents`. + """ + contents = self.readContents() + if not self.closed: + self.connectionLost() + return defer.succeed(contents) + + def connectionLost(self): + """Called if we die partway through reading a message. + + Truncate the :cvar:`mailfile` to null length, then close it. + """ + self.mailfile.truncate(0) + self.mailfile.close() + + +class MailMessage(object): + """Plugs into the Twisted Mail and receives an incoming message.""" + implements(smtp.IMessage) + + def __init__(self, context, fromCanonical=None): + """Create a new MailMessage from a MailContext. + + :param list lines: A list of lines from an incoming email message. + :type context: :class:`MailContext` + :param context: The configured context for the email server. + :type canonicalFrom: str or None + :param canonicalFrom: The canonical domain which this message was + received from. For example, if ``'gmail.com'`` is the configured + canonical domain for ``'googlemail.com'`` and a message is + received from the latter domain, then this would be set to the + former. + """ + self.context = context + self.fromCanonical = fromCanonical + self.lines = [] + self.nBytes = 0 + self.ignoring = False + + def lineReceived(self, line): + """Called when we get another line of an incoming message.""" + self.nBytes += len(line) + if self.nBytes > self.context.maximumSize: + self.ignoring = True + else: + self.lines.append(line) + if not safelog.safe_logging: + logging.debug("> %s", line.rstrip("\r\n")) + + def eomReceived(self): + """Called when we receive the end of a message.""" + if not self.ignoring: + self.reply() + return defer.succeed(None) + + def connectionLost(self): + """Called if we die partway through reading a message.""" + pass + + def getIncomingMessage(self): + """Create and parse an :rfc:`2822` message object for all ``lines`` + received thus far. + + :rtype: :api:`twisted.mail.smtp.rfc822.Message`. + :returns: A ``Message`` comprised of all lines received thus far. + """ + rawMessage = io.StringIO() + rawMessage.writelines([unicode('{0}\n'.format(ln)) for ln in self.lines]) + rawMessage.seek(0) + return smtp.rfc822.Message(rawMessage) + + def getClientAddress(self, incoming): + addrHeader = None + try: fromAddr = incoming.getaddr("From")[1] + except (IndexError, TypeError, AttributeError): pass + else: addrHeader = fromAddr + + if not addrHeader: + logging.warn("No From header on incoming mail.") + try: senderHeader = incoming.getaddr("Sender")[1] + except (IndexError, TypeError, AttributeError): pass + else: addrHeader = senderHeader + if not addrHeader: + logging.warn("No Sender header on incoming mail.") + else: + try: + client = smtp.Address(addr.normalizeEmail( + addrHeader, + self.context.domainMap, + self.context.domainRules)) + except (UnsupportedDomain, BadEmail, smtp.AddressError) as error: + logging.warn(error) + else: + return client + + def getRecipient(self, incoming): + """Find our **address** in a list of ``('NAME', '<ADDRESS>')`` pairs. + + If our address isn't found (which can't happen), return the default + context :header:`From` address so we can keep on working. + + :param str address: Our email address, as set in the + ``EMAIL_SMTP_FROM`` config option. + :param list addressList: A list of 2-tuples of strings, the first + string is a full name, username, common name, etc., and the second + is the entity's email address. + """ + address = self.context.fromAddr + addressList = incoming.getaddrlist("To") + + try: + ours = smtp.Address(address) + except smtp.AddressError as error: + logging.warn("Our address seems invalid: %r" % address) + logging.warn(error) + else: + for _, addr in addressList: + try: + maybeOurs = smtp.Address(addr) + except smtp.AddressError: + pass + else: + # See if the user looks familiar. We do a 'find' instead of + # compare because we might have a '+' address here. + if maybeOurs.local.find(ours.local) != -1: + return '@'.join([maybeOurs.local, maybeOurs.domain]) + return address + + def getCanonicalDomain(self, domain): + try: + canonical = canonicalizeEmailDomain(domain, self.context.canon) + except (UnsupportedDomain, BadEmail) as error: + logging.warn(error) + else: + return canonical + + def reply(self): + """Reply to an incoming email. Maybe. + + If no `response` is returned from :func:`createMailResponse`, then the + incoming email will not be responded to at all. This can happen for + several reasons, for example: if the DKIM signature was invalid or + missing, or if the incoming email came from an unacceptable domain, or + if there have been too many emails from this client in the allotted + time period. + + :rtype: :api:`twisted.internet.defer.Deferred` + :returns: A ``Deferred`` which will callback when the response has + been successfully sent, or errback if an error occurred while + sending the email. + """ + logging.info("Got an email; deciding whether to reply.") + + def _replyEB(fail): + """Errback for a :api:`twisted.mail.smtp.SMTPSenderFactory`. + + :param fail: A :api:`twisted.python.failure.Failure` which occurred during + the transaction. + """ + logging.debug("_replyToMailEB() called with %r" % fail) + error = fail.getTraceback() or "Unknown" + logging.error(error) + + d = defer.Deferred() + d.addErrback(_replyEB) + + incoming = self.getIncomingMessage() + recipient = self.getRecipient(incoming) + client = self.getClientAddress(incoming) + + if not client: + return d + + if not self.fromCanonical: + self.fromCanonical = self.getCanonicalDomain(client.domain) + rules = self.context.domainRules.get(self.fromCanonical, []) + if not checkDKIM(incoming, rules): + return d + + clientAddr = '@'.join([client.local, client.domain]) + messageID = incoming.getheader("Message-ID", None) + subject = incoming.getheader("Subject", None) or "[no subject]" + + # Look up the locale part in the 'To:' address, if there is one and + # get the appropriate Translation object: + lang = translations.getLocaleFromPlusAddr(recipient) + logging.info("Client requested email translation: %s" % lang) + + body = createResponseBody(self.lines, self.context, clientAddr, lang) + if not body: return d # The client was already warned. + + response = generateResponse(self.context.fromAddr, clientAddr, subject, + body, messageID, self.context.gpgContext) + if not response: return d + + logging.info("Sending reply to %s" % client) + factory = smtp.SMTPSenderFactory(self.context.smtpFromAddr, clientAddr, + response, d, retries=0, timeout=30) + reactor.connectTCP(self.context.smtpServerIP, + self.context.smtpServerPort, + factory) + return d + + +class MailDelivery(object): + """Plugs into Twisted Mail and handles SMTP commands.""" + implements(smtp.IMessageDelivery) + + def setBridgeDBContext(self, context): + self.context = context + self.fromCanonical = None + + def receivedHeader(self, helo, origin, recipients): + """Create the ``Received:`` header for an incoming email. + + :type helo: tuple + :param helo: The lines received during SMTP client HELO. + :type origin: :api:`twisted.mail.smtp.Address` + :param origin: The email address of the sender. + :type recipients: list + :param recipients: A list of :api:`twisted.mail.smtp.User` instances. + """ + cameFrom = "%s (%s [%s])" % (helo[0] or origin, helo[0], helo[1]) + cameFor = ', '.join(["<{0}>".format(recp.dest) for recp in recipients]) + hdr = str("Received: from %s for %s; %s" + % (cameFrom, cameFor, smtp.rfc822date())) + return hdr + + def validateFrom(self, helo, origin): + try: + logging.debug("ORIGIN: %r" % repr(origin.addrstr)) + canonical = canonicalizeEmailDomain(origin.domain, + self.context.canon) + except UnsupportedDomain as error: + logging.info(error) + raise smtp.SMTPBadSender(origin.domain) + except Exception as error: + logging.exception(error) + else: + logging.debug("Got canonical domain: %r" % canonical) + self.fromCanonical = canonical + return origin # This method *cannot* return None, or it'll cause a 503. + + def validateTo(self, user): + """If the local user that was addressed isn't our configured local user + or doesn't contain a '+' with a prefix matching the local configured + user: Yell. + """ + u = user.dest.local + # Hasplus? If yes, strip '+foo' + idx = u.find('+') + if idx != -1: + u = u[:idx] + if u != self.context.username: + raise smtp.SMTPBadRcpt(user) + return lambda: MailMessage(self.context, self.fromCanonical) + + +class MailFactory(smtp.SMTPFactory): + """Plugs into Twisted Mail; creates a new MailDelivery whenever we get + a connection on the SMTP port.""" + + def __init__(self, context=None, **kw): + smtp.SMTPFactory.__init__(self, **kw) + self.delivery = MailDelivery() + if context: + self.setBridgeDBContext(context) + + def setBridgeDBContext(self, context): + self.context = context + self.delivery.setBridgeDBContext(context) + + def buildProtocol(self, addr): + p = smtp.SMTPFactory.buildProtocol(self, addr) + p.delivery = self.delivery + return p + + +def addServer(config, distributor, schedule): + """Set up a SMTP server for responding to requests for bridges. + + :param config: A configuration object from Main. We use these + options:: + EMAIL_BIND_IP + EMAIL_PORT + EMAIL_N_BRIDGES_PER_ANSWER + EMAIL_DOMAIN_RULES + :type distributor: :class:`bridgedb.Dist.EmailBasedDistributor` + :param dist: A distributor which will handle database interactions, and + will decide which bridges to give to who and when. + :type schedule: :class:`bridgedb.Time.IntervalSchedule` + :param schedule: The schedule. XXX: Is this even used? + """ + context = MailContext(config, distributor, schedule) + factory = MailFactory(context) + + addr = config.EMAIL_BIND_IP or "" + port = config.EMAIL_PORT + + reactor.listenTCP(port, factory, interface=addr) + + # Set up a LoopingCall to run every 30 minutes and forget old email times. + lc = LoopingCall(distributor.cleanDatabase) + lc.start(1800, now=False) + + return factory diff --git a/lib/bridgedb/email/templates.py b/lib/bridgedb/email/templates.py new file mode 100644 index 0000000..6c25038 --- /dev/null +++ b/lib/bridgedb/email/templates.py @@ -0,0 +1,123 @@ +# -*- coding: utf-8 ; test-case-name: bridgedb.test.test_email_templates -*- +#_____________________________________________________________________________ +# +# This file is part of BridgeDB, a Tor bridge distribution system. +# +# :authors: Isis Lovecruft isis@torproject.org 0xA3ADB67A2CDB8B35 +# please also see AUTHORS file +# :copyright: (c) 2007-2014, The Tor Project, Inc. +# (c) 2013-2014, Isis Lovecruft +# :license: see LICENSE for licensing information +#_____________________________________________________________________________ + +"""Templates for formatting emails sent out by the email distributor.""" + +from __future__ import print_function +from __future__ import unicode_literals + +import logging +import os + +from bridgedb import strings +from bridgedb.Dist import MAX_EMAIL_RATE +from bridgedb.HTTPServer import TEMPLATE_DIR + + +def buildCommands(template): + # Tell them about the various email commands: + cmdlist = [] + cmdlist.append(template.gettext(strings.EMAIL_MISC_TEXT.get(3))) + for cmd, desc in strings.EMAIL_COMMANDS.items(): + command = ' ' + command += cmd + while not len(command) >= 25: # Align the command descriptions + command += ' ' + command += template.gettext(desc) + cmdlist.append(command) + + commands = "\n".join(cmdlist) + "\n\n" + # And include the currently supported transports: + commands += template.gettext(strings.EMAIL_MISC_TEXT.get(5)) + commands += "\n" + for pt in strings.CURRENT_TRANSPORTS: + commands += ' ' + pt + "\n" + + return commands + +def buildHowto(template): + howToTBB = template.gettext(strings.HOWTO_TBB[1]) % strings.EMAIL_SPRINTF["HOWTO_TBB1"] + howToTBB += u'\n\n' + howToTBB += template.gettext(strings.HOWTO_TBB[2]) + howToTBB += u'\n\n' + howToTBB += u'\n'.join(["> {0}".format(ln) for ln in + template.gettext(strings.HOWTO_TBB[3]).split('\n')]) + howToTBB += u'\n\n' + howToTBB += template.gettext(strings.HOWTO_TBB[4]) + howToTBB += u'\n\n' + howToTBB += strings.EMAIL_REFERENCE_LINKS.get("HOWTO_TBB1") + howToTBB += u'\n\n' + return howToTBB + +def buildKeyfile(template): + filename = os.path.join(TEMPLATE_DIR, 'bridgedb.asc') + + try: + with open(filename) as fh: + keyFile = fh.read() + except Exception as error: # pragma: no cover + logging.exception(error) + keyFile = u'' + else: + keyFile += u'\n\n' + + return keyFile + +def buildWelcomeText(template): + sections = [] + sections.append(template.gettext(strings.EMAIL_MISC_TEXT[4])) + + commands = buildCommands(template) + sections.append(commands) + + # Include the same messages as the homepage of the HTTPS distributor: + welcome = template.gettext(strings.WELCOME[0]) % strings.EMAIL_SPRINTF["WELCOME0"] + welcome += template.gettext(strings.WELCOME[1]) + welcome += template.gettext(strings.WELCOME[2]) % strings.EMAIL_SPRINTF["WELCOME2"] + sections.append(welcome) + + message = u"\n\n".join(sections) + # Add the markdown links at the end: + message += strings.EMAIL_REFERENCE_LINKS.get("WELCOME0") + message += u"\n" + + return message + +def buildBridgeAnswer(template): + # Give the user their bridges, i.e. the `answer`: + message = template.gettext(strings.EMAIL_MISC_TEXT[0]) + u"\n\n" \ + + template.gettext(strings.EMAIL_MISC_TEXT[1]) + u"\n\n" \ + + u"%s\n\n" + return message + +def buildMessage(template): + message = None + try: + message = buildBridgeAnswer(template) + message += buildHowto(template) + message += u'\n\n' + message += buildCommands(template) + except Exception as error: # pragma: no cover + logging.error("Error while formatting email message template:") + logging.exception(error) + return message + +def buildSpamWarning(template): + message = None + try: + message = template.gettext(strings.EMAIL_MISC_TEXT[0]) + u"\n\n" \ + + template.gettext(strings.EMAIL_MISC_TEXT[2]) + u"\n" + message = message % str(MAX_EMAIL_RATE / 3600) + except Exception as error: # pragma: no cover + logging.error("Error while formatting email spam template:") + logging.exception(error) + return message diff --git a/setup.py b/setup.py index 1b8c259..e21dbef 100644 --- a/setup.py +++ b/setup.py @@ -278,6 +278,7 @@ setuptools.setup( download_url='https://gitweb.torproject.org/bridgedb.git', package_dir={'': 'lib'}, packages=['bridgedb', + 'bridgedb.email', 'bridgedb.parse', 'bridgedb.test'], scripts=['scripts/bridgedb'],