New keymanager async API

7 files changed, 474 insertions, 444 deletions

diff --git a/mail/src/leap/mail/imap/fetch.py b/mail/src/leap/mail/imap/fetch.py
index 01373be..dbc726a 100644
--- a/mail/src/leap/mail/imap/fetch.py
+++ b/mail/src/leap/mail/imap/fetch.py
@@ -36,7 +36,6 @@ from twisted.internet import defer, reactor
 from twisted.internet.task import LoopingCall
 from twisted.internet.task import deferLater
 from u1db import errors as u1db_errors
-from zope.proxy import sameProxiedObjects
 
 from leap.common import events as leap_events
 from leap.common.check import leap_assert, leap_assert_type
@@ -138,13 +137,6 @@ class LeapIncomingMail(object):
         # initialize a mail parser only once
         self._parser = Parser()
 
-    @property
-    def _pkey(self):
-        if sameProxiedObjects(self._keymanager, None):
-            logger.warning('tried to get key, but null keymanager found')
-            return None
-        return self._keymanager.get_key(self._userid, OpenPGPKey, private=True)
-
     #
     # Public API: fetch, start_loop, stop.
     #
@@ -312,40 +304,46 @@ class LeapIncomingMail(object):
         :param doc: A document containing an encrypted message.
         :type doc: SoledadDocument
 
-        :return: A tuple containing the document and the decrypted message.
-        :rtype: (SoledadDocument, str)
+        :return: A Deferred that will be fired with the document and the
+                 decrypted message.
+        :rtype: SoledadDocument, str
         """
         log.msg('decrypting msg')
-        success = False
 
-        try:
-            decrdata = self._keymanager.decrypt(
-                doc.content[ENC_JSON_KEY],
-                self._pkey)
-            success = True
-        except Exception as exc:
-            # XXX move this to errback !!!
-            logger.error("Error while decrypting msg: %r" % (exc,))
-            decrdata = ""
-        leap_events.signal(IMAP_MSG_DECRYPTED, "1" if success else "0")
+        def process_decrypted(res):
+            if isinstance(res, tuple):
+                decrdata, _ = res
+                success = True
+            else:
+                decrdata = ""
+                success = False
 
-        data = self._process_decrypted_doc((doc, decrdata))
-        return (doc, data)
+            leap_events.signal(IMAP_MSG_DECRYPTED, "1" if success else "0")
 
-    def _process_decrypted_doc(self, msgtuple):
+            data = self._process_decrypted_doc(doc, decrdata)
+            return doc, data
+
+        d = self._keymanager.decrypt(
+            doc.content[ENC_JSON_KEY],
+            self._userid, OpenPGPKey)
+        d.addErrback(self._errback)
+        d.addCallback(process_decrypted)
+        return d
+
+    def _process_decrypted_doc(self, doc, data):
         """
         Process a document containing a succesfully decrypted message.
 
-        :param msgtuple: a tuple consisting of a SoledadDocument
-                         instance containing the incoming message
-                         and data, the json-encoded, decrypted content of the
-                         incoming message
-        :type msgtuple: (SoledadDocument, str)
+        :param doc: the incoming message
+        :type doc: SoledadDocument
+        :param data: the json-encoded, decrypted content of the incoming
+                     message
+        :type data: str
+
         :return: the processed data.
         :rtype: str
         """
         log.msg('processing decrypted doc')
-        doc, data = msgtuple
 
         # XXX turn this into an errBack for each one of
         # the deferreds that would process an individual document
@@ -421,45 +419,40 @@ class LeapIncomingMail(object):
         encoding = get_email_charset(data)
         msg = self._parser.parsestr(data)
 
-        # try to obtain sender public key
-        senderPubkey = None
         fromHeader = msg.get('from', None)
+        senderAddress = None
         if (fromHeader is not None
             and (msg.get_content_type() == MULTIPART_ENCRYPTED
                  or msg.get_content_type() == MULTIPART_SIGNED)):
-            _, senderAddress = parseaddr(fromHeader)
-            try:
-                senderPubkey = self._keymanager.get_key(
-                    senderAddress, OpenPGPKey)
-            except keymanager_errors.KeyNotFound:
-                pass
-
-        valid_sig = False  # we will add a header saying if sig is valid
-        decrypt_multi = self._decrypt_multipart_encrypted_msg
-        decrypt_inline = self._maybe_decrypt_inline_encrypted_msg
+                senderAddress = parseaddr(fromHeader)
+
+        def add_leap_header(decrmsg, signkey):
+            if (senderAddress is None or
+                    isinstance(signkey, keymanager_errors.KeyNotFound)):
+                decrmsg.add_header(
+                    self.LEAP_SIGNATURE_HEADER,
+                    self.LEAP_SIGNATURE_COULD_NOT_VERIFY)
+            elif isinstance(signkey, keymanager_errors.InvalidSignature):
+                decrmsg.add_header(
+                    self.LEAP_SIGNATURE_HEADER,
+                    self.LEAP_SIGNATURE_INVALID)
+            else:
+                decrmsg.add_header(
+                    self.LEAP_SIGNATURE_HEADER,
+                    self.LEAP_SIGNATURE_VALID,
+                    pubkey=signkey.key_id)
+            return decrmsg.as_string()
 
         if msg.get_content_type() == MULTIPART_ENCRYPTED:
-            decrmsg, valid_sig = decrypt_multi(
-                msg, encoding, senderPubkey)
+            d = self._decrypt_multipart_encrypted_msg(
+                msg, encoding, senderAddress)
         else:
-            decrmsg, valid_sig = decrypt_inline(
-                msg, encoding, senderPubkey)
-
-        # add x-leap-signature header
-        if senderPubkey is None:
-            decrmsg.add_header(
-                self.LEAP_SIGNATURE_HEADER,
-                self.LEAP_SIGNATURE_COULD_NOT_VERIFY)
-        else:
-            decrmsg.add_header(
-                self.LEAP_SIGNATURE_HEADER,
-                self.LEAP_SIGNATURE_VALID if valid_sig else
-                self.LEAP_SIGNATURE_INVALID,
-                pubkey=senderPubkey.key_id)
-
-        return decrmsg.as_string()
+            d = self._maybe_decrypt_inline_encrypted_msg(
+                msg, encoding, senderAddress)
+        d.addCallback(add_leap_header)
+        return d
 
-    def _decrypt_multipart_encrypted_msg(self, msg, encoding, senderPubkey):
+    def _decrypt_multipart_encrypted_msg(self, msg, encoding, senderAddress):
         """
         Decrypt a message with content-type 'multipart/encrypted'.
 
@@ -467,12 +460,13 @@ class LeapIncomingMail(object):
         :type msg: Message
         :param encoding: The encoding of the email message.
         :type encoding: str
-        :param senderPubkey: The key of the sender of the message.
-        :type senderPubkey: OpenPGPKey
+        :param senderAddress: The email address of the sender of the message.
+        :type senderAddress: str
 
-        :return: A tuple containing a decrypted message and
-                 a bool indicating whether the signature is valid.
-        :rtype: (Message, bool)
+        :return: A Deferred that will be fired with a tuple containing a
+                 decrypted Message and the signing OpenPGPKey if the signature
+                 is valid or InvalidSignature or KeyNotFound.
+        :rtype: Deferred
         """
         log.msg('decrypting multipart encrypted msg')
         msg = copy.deepcopy(msg)
@@ -483,33 +477,33 @@ class LeapIncomingMail(object):
         encdata = pgpencmsg.get_payload()
 
         # decrypt or fail gracefully
-        try:
-            decrdata, valid_sig = self._decrypt_and_verify_data(
-                encdata, senderPubkey)
-        except keymanager_errors.DecryptError as e:
-            logger.warning('Failed to decrypt encrypted message (%s). '
-                           'Storing message without modifications.' % str(e))
-            # Bailing out!
-            return (msg, False)
+        def build_msg(res):
+            decrdata, signkey = res
 
-        decrmsg = self._parser.parsestr(decrdata)
-        # remove original message's multipart/encrypted content-type
-        del(msg['content-type'])
+            decrmsg = self._parser.parsestr(decrdata)
+            # remove original message's multipart/encrypted content-type
+            del(msg['content-type'])
 
-        # replace headers back in original message
-        for hkey, hval in decrmsg.items():
-            try:
-                # this will raise KeyError if header is not present
-                msg.replace_header(hkey, hval)
-            except KeyError:
-                msg[hkey] = hval
+            # replace headers back in original message
+            for hkey, hval in decrmsg.items():
+                try:
+                    # this will raise KeyError if header is not present
+                    msg.replace_header(hkey, hval)
+                except KeyError:
+                    msg[hkey] = hval
+
+            # all ok, replace payload by unencrypted payload
+            msg.set_payload(decrmsg.get_payload())
+            return (msg, signkey)
 
-        # all ok, replace payload by unencrypted payload
-        msg.set_payload(decrmsg.get_payload())
-        return (msg, valid_sig)
+        d = self._keymanager.decrypt(
+            encdata, self._userid, OpenPGPKey,
+            verify=senderAddress)
+        d.addCallbacks(build_msg, self._decryption_error, errbackArgs=(msg,))
+        return d
 
     def _maybe_decrypt_inline_encrypted_msg(self, origmsg, encoding,
-                                            senderPubkey):
+                                            senderAddress):
         """
         Possibly decrypt an inline OpenPGP encrypted message.
 
@@ -517,12 +511,13 @@ class LeapIncomingMail(object):
         :type origmsg: Message
         :param encoding: The encoding of the email message.
         :type encoding: str
-        :param senderPubkey: The key of the sender of the message.
-        :type senderPubkey: OpenPGPKey
+        :param senderAddress: The email address of the sender of the message.
+        :type senderAddress: str
 
-        :return: A tuple containing a decrypted message and
-                 a bool indicating whether the signature is valid.
-        :rtype: (Message, bool)
+        :return: A Deferred that will be fired with a tuple containing a
+                 decrypted Message and the signing OpenPGPKey if the signature
+                 is valid or InvalidSignature or KeyNotFound.
+        :rtype: Deferred
         """
         log.msg('maybe decrypting inline encrypted msg')
         # serialize the original message
@@ -530,54 +525,48 @@ class LeapIncomingMail(object):
         g = Generator(buf)
         g.flatten(origmsg)
         data = buf.getvalue()
+
+        def decrypted_data(res):
+            decrdata, signkey = res
+            return data.replace(pgp_message, decrdata), signkey
+
+        def encode_and_return(res):
+            data, signkey = res
+            if isinstance(data, unicode):
+                data = data.encode(encoding, 'replace')
+            return (self._parser.parsestr(data), signkey)
+
         # handle exactly one inline PGP message
-        valid_sig = False
         if PGP_BEGIN in data:
             begin = data.find(PGP_BEGIN)
             end = data.find(PGP_END)
             pgp_message = data[begin:end + len(PGP_END)]
-            try:
-                decrdata, valid_sig = self._decrypt_and_verify_data(
-                    pgp_message, senderPubkey)
-                # replace encrypted by decrypted content
-                data = data.replace(pgp_message, decrdata)
-            except keymanager_errors.DecryptError:
-                logger.warning('Failed to decrypt potential inline encrypted '
-                               'message. Storing message as is...')
-
-        # if message is not encrypted, return raw data
-        if isinstance(data, unicode):
-            data = data.encode(encoding, 'replace')
-        return (self._parser.parsestr(data), valid_sig)
+            d = self._keymanager.decrypt(
+                pgp_message, self._userid, OpenPGPKey,
+                verify=senderAddress)
+            d.addCallbacks(decrypted_data, self._decryption_error,
+                           errbackArgs=(data,))
+        else:
+            d = defer.succeed((data, None))
+        d.addCallback(encode_and_return)
+        return d
 
-    def _decrypt_and_verify_data(self, data, senderPubkey):
+    def _decryption_error(self, failure, msg):
         """
-        Decrypt C{data} using our private key and attempt to verify a
-        signature using C{senderPubkey}.
-
-        :param data: The text to be decrypted.
-        :type data: unicode
-        :param senderPubkey: The public key of the sender of the message.
-        :type senderPubkey: OpenPGPKey
-
-        :return: The decrypted data and a boolean stating whether the
-                 signature could be verified.
-        :rtype: (str, bool)
-
-        :raise DecryptError: Raised if failed to decrypt.
+        Check for known decryption errors
         """
-        log.msg('decrypting and verifying data')
-        valid_sig = False
-        try:
-            decrdata = self._keymanager.decrypt(
-                data, self._pkey,
-                verify=senderPubkey)
-            if senderPubkey is not None:
-                valid_sig = True
-        except keymanager_errors.InvalidSignature:
-            decrdata = self._keymanager.decrypt(
-                data, self._pkey)
-        return (decrdata, valid_sig)
+        if failure.check(keymanager_errors.DecryptError):
+            logger.warning('Failed to decrypt encrypted message (%s). '
+                           'Storing message without modifications.'
+                           % str(failure.value))
+            return (msg, None)
+        elif failure.check(keymanager_errors.KeyNotFound):
+            logger.error('Failed to find private key for decryption (%s). '
+                         'Storing message without modifications.'
+                         % str(failure.value))
+            return (msg, None)
+        else:
+            return failure
 
     def _extract_keys(self, msgtuple):
         """
@@ -592,6 +581,10 @@ class LeapIncomingMail(object):
                          and data, the json-encoded, decrypted content of the
                          incoming message
         :type msgtuple: (SoledadDocument, str)
+
+        :return: A Deferred that will be fired with msgtuple when key
+                 extraction finishes
+        :rtype: Deferred
         """
         OpenPGP_HEADER = 'OpenPGP'
         doc, data = msgtuple
@@ -603,13 +596,17 @@ class LeapIncomingMail(object):
         _, fromAddress = parseaddr(msg['from'])
 
         header = msg.get(OpenPGP_HEADER, None)
+        dh = defer.success()
         if header is not None:
-            self._extract_openpgp_header(header, fromAddress)
+            dh = self._extract_openpgp_header(header, fromAddress)
 
+        da = defer.success()
         if msg.is_multipart():
-            self._extract_attached_key(msg.get_payload(), fromAddress)
+            da = self._extract_attached_key(msg.get_payload(), fromAddress)
 
-        return msgtuple
+        d = defer.gatherResults([dh, da])
+        d.addCallback(lambda _: msgtuple)
+        return d
 
     def _extract_openpgp_header(self, header, address):
         """
@@ -619,7 +616,11 @@ class LeapIncomingMail(object):
         :type header: str
         :param address: email address in the from header
         :type address: str
+
+        :return: A Deferred that will be fired when header extraction is done
+        :rtype: Deferred
         """
+        d = defer.success()
         fields = dict([f.strip(' ').split('=') for f in header.split(';')])
         if 'url' in fields:
             url = shlex.split(fields['url'])[0]  # remove quotations
@@ -627,21 +628,28 @@ class LeapIncomingMail(object):
             addressHostname = address.split('@')[1]
             if (urlparts.scheme == 'https'
                     and urlparts.hostname == addressHostname):
-                try:
-                    self._keymanager.fetch_key(address, url, OpenPGPKey)
-                    logger.info("Imported key from header %s" % (url,))
-                except keymanager_errors.KeyNotFound:
-                    logger.warning("Url from OpenPGP header %s failed"
-                                   % (url,))
-                except keymanager_errors.KeyAttributesDiffer:
-                    logger.warning("Key from OpenPGP header url %s didn't "
-                                   "match the from address %s"
-                                   % (url, address))
+                def fetch_error(failure):
+                    if failure.check(keymanager_errors.KeyNotFound):
+                        logger.warning("Url from OpenPGP header %s failed"
+                                       % (url,))
+                    elif failure.check(keymanager_errors.KeyAttributesDiffer):
+                        logger.warning("Key from OpenPGP header url %s didn't "
+                                       "match the from address %s"
+                                       % (url, address))
+                    else:
+                        return failure
+
+                d = self._keymanager.fetch_key(address, url, OpenPGPKey)
+                d.addCallback(
+                    lambda _:
+                    logger.info("Imported key from header %s" % (url,)))
+                d.addErrback(fetch_error)
             else:
                 logger.debug("No valid url on OpenPGP header %s" % (url,))
         else:
             logger.debug("There is no url on the OpenPGP header: %s"
                          % (header,))
+        return d
 
     def _extract_attached_key(self, attachments, address):
         """
@@ -651,16 +659,22 @@ class LeapIncomingMail(object):
         :type attachments: list(email.Message)
         :param address: email address in the from header
         :type address: str
+
+        :return: A Deferred that will be fired when all the keys are stored
+        :rtype: Deferred
         """
         MIME_KEY = "application/pgp-keys"
 
+        deferreds = []
         for attachment in attachments:
             if MIME_KEY == attachment.get_content_type():
                 logger.debug("Add key from attachment")
-                self._keymanager.put_raw_key(
+                d = self._keymanager.put_raw_key(
                     attachment.get_payload(),
                     OpenPGPKey,
                     address=address)
+                deferreds.append(d)
+        return defer.gatherResults(deferreds)
 
     def _add_message_locally(self, msgtuple):
         """
@@ -672,6 +686,9 @@ class LeapIncomingMail(object):
                          and data, the json-encoded, decrypted content of the
                          incoming message
         :type msgtuple: (SoledadDocument, str)
+
+        :return: A Deferred that will be fired when the messages is stored
+        :rtype: Defferred
         """
         doc, data = msgtuple
         log.msg('adding message %s to local db' % (doc.doc_id,))
@@ -690,6 +707,7 @@ class LeapIncomingMail(object):
         d = self._inbox.addMessage(data, flags=(self.RECENT_FLAG,),
                                    notify_on_disk=True)
         d.addCallbacks(msgSavedCallback, self._errback)
+        return d
 
     #
     # helpers
diff --git a/mail/src/leap/mail/imap/tests/test_incoming_mail.py b/mail/src/leap/mail/imap/tests/test_incoming_mail.py
index ce6d56a..03c0164 100644
--- a/mail/src/leap/mail/imap/tests/test_incoming_mail.py
+++ b/mail/src/leap/mail/imap/tests/test_incoming_mail.py
@@ -28,7 +28,6 @@ from email.mime.application import MIMEApplication
 from email.mime.multipart import MIMEMultipart
 from email.parser import Parser
 from mock import Mock
-from twisted.trial import unittest
 
 from leap.keymanager.openpgp import OpenPGPKey
 from leap.mail.imap.account import SoledadBackedAccount
@@ -48,7 +47,7 @@ from leap.soledad.common.crypto import (
 )
 
 
-class LeapIncomingMailTestCase(TestCaseWithKeyManager, unittest.TestCase):
+class LeapIncomingMailTestCase(TestCaseWithKeyManager):
     """
     Tests for the incoming mail parser
     """
@@ -147,31 +146,42 @@ subject: independence of cyberspace
         key = MIMEApplication("", "pgp-keys")
         key.set_payload(KEY)
         message.attach(key)
-        email = self._create_incoming_email(message.as_string())
-        self._mock_soledad_get_from_index(fields.JUST_MAIL_IDX, [email])
-        self.fetcher._keymanager.put_raw_key = Mock()
 
         def put_raw_key_called(ret):
             self.fetcher._keymanager.put_raw_key.assert_called_once_with(
                 KEY, OpenPGPKey, address=self.FROM_ADDRESS)
 
-        d = self.fetcher.fetch()
+        d = self.mock_fetch(message.as_string())
         d.addCallback(put_raw_key_called)
         return d
 
+    def _mock_fetch(self, message):
+        self.fetcher._keymanager.fetch_key = Mock()
+        d = self._create_incoming_email(message)
+        d.addCallback(
+            lambda email:
+            self._mock_soledad_get_from_index(fields.JUST_MAIL_IDX, [email]))
+        d.addCallback(lambda _: self.fetcher.fetch())
+        return d
+
     def _create_incoming_email(self, email_str):
         email = SoledadDocument()
-        pubkey = self._km.get_key(ADDRESS, OpenPGPKey)
         data = json.dumps(
             {"incoming": True, "content": email_str},
             ensure_ascii=False)
-        email.content = {
-            fields.INCOMING_KEY: True,
-            fields.ERROR_DECRYPTING_KEY: False,
-            ENC_SCHEME_KEY: EncryptionSchemes.PUBKEY,
-            ENC_JSON_KEY: str(self._km.encrypt(data, pubkey))
-        }
-        return email
+
+        def set_email_content(pubkey):
+            email.content = {
+                fields.INCOMING_KEY: True,
+                fields.ERROR_DECRYPTING_KEY: False,
+                ENC_SCHEME_KEY: EncryptionSchemes.PUBKEY,
+                ENC_JSON_KEY: str(self._km.encrypt(data, pubkey))
+            }
+            return email
+
+        d = self._km.get_key(ADDRESS, OpenPGPKey)
+        d.addCallback(set_email_content)
+        return d
 
     def _mock_soledad_get_from_index(self, index_name, value):
         get_from_index = self._soledad.get_from_index
diff --git a/mail/src/leap/mail/service.py b/mail/src/leap/mail/service.py
index f6e4d11..a99f13a 100644
--- a/mail/src/leap/mail/service.py
+++ b/mail/src/leap/mail/service.py
@@ -24,7 +24,6 @@ from OpenSSL import SSL
 from twisted.mail import smtp
 from twisted.internet import reactor
 from twisted.internet import defer
-from twisted.internet.threads import deferToThread
 from twisted.protocols.amp import ssl
 from twisted.python import log
 
@@ -111,17 +110,17 @@ class OutgoingMail:
         :type recipient: smtp.User
         :return: a deferred which delivers the message when fired
         """
-        d = deferToThread(lambda: self._maybe_encrypt_and_sign(raw, recipient))
+        d = self._maybe_encrypt_and_sign(raw, recipient)
         d.addCallback(self._route_msg)
         d.addErrback(self.sendError)
-
         return d
 
     def sendSuccess(self, smtp_sender_result):
         """
         Callback for a successful send.
 
-        :param smtp_sender_result: The result from the ESMTPSender from _route_msg
+        :param smtp_sender_result: The result from the ESMTPSender from
+                                   _route_msg
         :type smtp_sender_result: tuple(int, list(tuple))
         """
         dest_addrstr = smtp_sender_result[1][0][0]
@@ -145,7 +144,8 @@ class OutgoingMail:
         """
         Sends the msg using the ESMTPSenderFactory.
 
-        :param encrypt_and_sign_result: A tuple containing the 'maybe' encrypted message and the recipient
+        :param encrypt_and_sign_result: A tuple containing the 'maybe'
+                                        encrypted message and the recipient
         :type encrypt_and_sign_result: tuple
         """
         message, recipient = encrypt_and_sign_result
@@ -173,7 +173,6 @@ class OutgoingMail:
             self._host, self._port, factory,
             contextFactory=SSLContextFactory(self._cert, self._key))
 
-
     def _maybe_encrypt_and_sign(self, raw, recipient):
         """
         Attempt to encrypt and sign the outgoing message.
@@ -209,16 +208,20 @@ class OutgoingMail:
         :param recipient: The recipient for the message
         :type: recipient: smtp.User
 
+        :return: A Deferred that will be fired with a MIMEMultipart message
+                 and the original recipient Message
+        :rtype: Deferred
         """
         # pass if the original message's content-type is "multipart/encrypted"
         lines = raw.split('\r\n')
         origmsg = Parser().parsestr(raw)
 
         if origmsg.get_content_type() == 'multipart/encrypted':
-            return origmsg
+            return defer.success((origmsg, recipient))
 
         from_address = validate_address(self._from_address)
         username, domain = from_address.split('@')
+        to_address = validate_address(recipient.dest.addrstr)
 
         # add a nice footer to the outgoing message
         # XXX: footer will eventually optional or be removed
@@ -230,80 +233,93 @@ class OutgoingMail:
 
         origmsg = Parser().parsestr('\r\n'.join(lines))
 
-        # get sender and recipient data
-        signkey = self._keymanager.get_key(from_address, OpenPGPKey, private=True)
-        log.msg("Will sign the message with %s." % signkey.fingerprint)
-        to_address = validate_address(recipient.dest.addrstr)
-        try:
-            # try to get the recipient pubkey
-            pubkey = self._keymanager.get_key(to_address, OpenPGPKey)
-            log.msg("Will encrypt the message to %s." % pubkey.fingerprint)
-            signal(proto.SMTP_START_ENCRYPT_AND_SIGN,
-                   "%s,%s" % (self._from_address, to_address))
-            newmsg = self._encrypt_and_sign(origmsg, pubkey, signkey)
-
+        def signal_encrypt_sign(newmsg):
             signal(proto.SMTP_END_ENCRYPT_AND_SIGN,
                    "%s,%s" % (self._from_address, to_address))
-        except KeyNotFound:
-            # at this point we _can_ send unencrypted mail, because if the
-            # configuration said the opposite the address would have been
-            # rejected in SMTPDelivery.validateTo().
-            log.msg('Will send unencrypted message to %s.' % to_address)
-            signal(proto.SMTP_START_SIGN, self._from_address)
-            newmsg = self._sign(origmsg, signkey)
-            signal(proto.SMTP_END_SIGN, self._from_address)
-        return newmsg, recipient
+            return newmsg, recipient
 
+        def signal_sign(newmsg):
+            signal(proto.SMTP_END_SIGN, self._from_address)
+            return newmsg, recipient
+
+        def if_key_not_found_send_unencrypted(failure):
+            if failure.check(KeyNotFound):
+                log.msg('Will send unencrypted message to %s.' % to_address)
+                signal(proto.SMTP_START_SIGN, self._from_address)
+                d = self._sign(origmsg, from_address)
+                d.addCallback(signal_sign)
+                return d
+            else:
+                return failure
+
+        log.msg("Will encrypt the message with %s and sign with %s."
+                % (to_address, from_address))
+        signal(proto.SMTP_START_ENCRYPT_AND_SIGN,
+               "%s,%s" % (self._from_address, to_address))
+        d = self._encrypt_and_sign(origmsg, to_address, from_address)
+        d.addCallbacks(signal_encrypt_sign, if_key_not_found_send_unencrypted)
+        return d
 
-    def _encrypt_and_sign(self, origmsg, pubkey, signkey):
+    def _encrypt_and_sign(self, origmsg, encrypt_address, sign_address):
         """
         Create an RFC 3156 compliang PGP encrypted and signed message using
-        C{pubkey} to encrypt and C{signkey} to sign.
+        C{encrypt_address} to encrypt and C{sign_address} to sign.
 
         :param origmsg: The original message
         :type origmsg: email.message.Message
-        :param pubkey: The public key used to encrypt the message.
-        :type pubkey: OpenPGPKey
-        :param signkey: The private key used to sign the message.
-        :type signkey: OpenPGPKey
-        :return: The encrypted and signed message
-        :rtype: MultipartEncrypted
+        :param encrypt_address: The address used to encrypt the message.
+        :type encrypt_address: str
+        :param sign_address: The address used to sign the message.
+        :type sign_address: str
+
+        :return: A Deferred with the MultipartEncrypted message
+        :rtype: Deferred
         """
         # create new multipart/encrypted message with 'pgp-encrypted' protocol
-        newmsg = MultipartEncrypted('application/pgp-encrypted')
-        # move (almost) all headers from original message to the new message
-        self._fix_headers(origmsg, newmsg, signkey)
-        # create 'application/octet-stream' encrypted message
-        encmsg = MIMEApplication(
-            self._keymanager.encrypt(origmsg.as_string(unixfrom=False), pubkey,
-                                     sign=signkey),
-            _subtype='octet-stream', _encoder=lambda x: x)
-        encmsg.add_header('content-disposition', 'attachment',
-                          filename='msg.asc')
-        # create meta message
-        metamsg = PGPEncrypted()
-        metamsg.add_header('Content-Disposition', 'attachment')
-        # attach pgp message parts to new message
-        newmsg.attach(metamsg)
-        newmsg.attach(encmsg)
-        return newmsg
-
-
-    def _sign(self, origmsg, signkey):
+
+        def encrypt(res):
+            newmsg, origmsg = res
+            d = self._keymanager.encrypt(
+                origmsg.as_string(unixfrom=False),
+                encrypt_address, OpenPGPKey, sign=sign_address)
+            d.addCallback(lambda encstr: (newmsg, encstr))
+            return d
+
+        def create_encrypted_message(res):
+            newmsg, encstr = res
+            encmsg = MIMEApplication(
+                encstr, _subtype='octet-stream', _encoder=lambda x: x)
+            encmsg.add_header('content-disposition', 'attachment',
+                              filename='msg.asc')
+            # create meta message
+            metamsg = PGPEncrypted()
+            metamsg.add_header('Content-Disposition', 'attachment')
+            # attach pgp message parts to new message
+            newmsg.attach(metamsg)
+            newmsg.attach(encmsg)
+            return newmsg
+
+        d = self._fix_headers(
+            origmsg,
+            MultipartEncrypted('application/pgp-encrypted'),
+            sign_address)
+        d.addCallback(encrypt)
+        d.addCallback(create_encrypted_message)
+        return d
+
+    def _sign(self, origmsg, sign_address):
         """
-        Create an RFC 3156 compliant PGP signed MIME message using C{signkey}.
+        Create an RFC 3156 compliant PGP signed MIME message using
+        C{sign_address}.
 
         :param origmsg: The original message
         :type origmsg: email.message.Message
-        :param signkey: The private key used to sign the message.
-        :type signkey: leap.common.keymanager.openpgp.OpenPGPKey
-        :return: The signed message.
-        :rtype: MultipartSigned
+        :param sign_address: The address used to sign the message.
+        :type sign_address: str
+
+        :return: A Deferred with the MultipartSigned message.
+        :rtype: Deferred
         """
-        # create new multipart/signed message
-        newmsg = MultipartSigned('application/pgp-signature', 'pgp-sha512')
-        # move (almost) all headers from original message to the new message
-        self._fix_headers(origmsg, newmsg, signkey)
         # apply base64 content-transfer-encoding
         encode_base64_rec(origmsg)
         # get message text with headers and replace \n for \r\n
@@ -316,17 +332,27 @@ class OutgoingMail:
         if origmsg.is_multipart():
             if not msgtext.endswith("\r\n"):
                 msgtext += "\r\n"
-        # calculate signature
-        signature = self._keymanager.sign(msgtext, signkey, digest_algo='SHA512',
-                                          clearsign=False, detach=True, binary=False)
-        sigmsg = PGPSignature(signature)
-        # attach original message and signature to new message
-        newmsg.attach(origmsg)
-        newmsg.attach(sigmsg)
-        return newmsg
 
+        def create_signed_message(res):
+            (msg, _), signature = res
+            sigmsg = PGPSignature(signature)
+            # attach original message and signature to new message
+            msg.attach(origmsg)
+            msg.attach(sigmsg)
+            return msg
+
+        dh = self._fix_headers(
+            origmsg,
+            MultipartSigned('application/pgp-signature', 'pgp-sha512'),
+            sign_address)
+        ds = self._keymanager.sign(
+            msgtext, sign_address, OpenPGPKey, digest_algo='SHA512',
+            clearsign=False, detach=True, binary=False)
+        d = defer.gatherResults([dh, ds])
+        d.addCallback(create_signed_message)
+        return d
 
-    def _fix_headers(self, origmsg, newmsg, signkey):
+    def _fix_headers(self, origmsg, newmsg, sign_address):
         """
         Move some headers from C{origmsg} to C{newmsg}, delete unwanted
         headers from C{origmsg} and add new headers to C{newms}.
@@ -360,8 +386,13 @@ class OutgoingMail:
         :type origmsg: email.message.Message
         :param newmsg: The new message being created.
         :type newmsg: email.message.Message
-        :param signkey: The key used to sign C{newmsg}
-        :type signkey: OpenPGPKey
+        :param sign_address: The address used to sign C{newmsg}
+        :type sign_address: str
+
+        :return: A Deferred with a touple:
+                 (new Message with the unencrypted headers,
+                  original Message with headers removed)
+        :rtype: Deferred
         """
         # move headers from origmsg to newmsg
         headers = origmsg.items()
@@ -375,11 +406,17 @@ class OutgoingMail:
             del (origmsg[hkey])
         # add a new message-id to newmsg
         newmsg.add_header('Message-Id', smtp.messageid())
-        # add openpgp header to newmsg
-        username, domain = signkey.address.split('@')
-        newmsg.add_header(
-            'OpenPGP', 'id=%s' % signkey.key_id,
-            url='https://%s/key/%s' % (domain, username),
-            preference='signencrypt')
         # delete user-agent from origmsg
         del (origmsg['user-agent'])
+
+        def add_openpgp_header(signkey):
+            username, domain = sign_address.split('@')
+            newmsg.add_header(
+                'OpenPGP', 'id=%s' % signkey.key_id,
+                url='https://%s/key/%s' % (domain, username),
+                preference='signencrypt')
+            return newmsg, origmsg
+
+        d = self._keymanager.get_key(sign_address, OpenPGPKey, private=True)
+        d.addCallback(add_openpgp_header)
+        return d
diff --git a/mail/src/leap/mail/smtp/gateway.py b/mail/src/leap/mail/smtp/gateway.py
index b022091..d58c581 100644
--- a/mail/src/leap/mail/smtp/gateway.py
+++ b/mail/src/leap/mail/smtp/gateway.py
@@ -48,7 +48,6 @@ from leap.mail.smtp.rfc3156 import (
     RFC3156CompliantGenerator,
 )
 
-from leap.mail.service import OutgoingMail
 # replace email generator with a RFC 3156 compliant one.
 from email import generator
 
@@ -197,22 +196,31 @@ class SMTPDelivery(object):
             accepted.
         """
         # try to find recipient's public key
-        try:
-            address = validate_address(user.dest.addrstr)
-            # verify if recipient key is available in keyring
-            self._km.get_key(address, OpenPGPKey)  # might raise KeyNotFound
+        address = validate_address(user.dest.addrstr)
+
+        # verify if recipient key is available in keyring
+        def found(_):
             log.msg("Accepting mail for %s..." % user.dest.addrstr)
             signal(proto.SMTP_RECIPIENT_ACCEPTED_ENCRYPTED, user.dest.addrstr)
-        except KeyNotFound:
-            # if key was not found, check config to see if will send anyway.
-            if self._encrypted_only:
-                signal(proto.SMTP_RECIPIENT_REJECTED, user.dest.addrstr)
-                raise smtp.SMTPBadRcpt(user.dest.addrstr)
-            log.msg("Warning: will send an unencrypted message (because "
-                    "encrypted_only' is set to False).")
-            signal(
-                proto.SMTP_RECIPIENT_ACCEPTED_UNENCRYPTED, user.dest.addrstr)
-        return lambda: EncryptedMessage(user, self._outgoing_mail)
+
+        def not_found(failure):
+            if failure.check(KeyNotFound):
+                # if key was not found, check config to see if will send anyway
+                if self._encrypted_only:
+                    signal(proto.SMTP_RECIPIENT_REJECTED, user.dest.addrstr)
+                    raise smtp.SMTPBadRcpt(user.dest.addrstr)
+                log.msg("Warning: will send an unencrypted message (because "
+                        "encrypted_only' is set to False).")
+                signal(
+                    proto.SMTP_RECIPIENT_ACCEPTED_UNENCRYPTED,
+                    user.dest.addrstr)
+            else:
+                return failure
+
+        d = self._km.get_key(address, OpenPGPKey)  # might raise KeyNotFound
+        d.addCallbacks(found, not_found)
+        d.addCallbac(lambda _: EncryptedMessage(user, self._outgoing_mail))
+        return d
 
     def validateFrom(self, helo, origin):
         """
diff --git a/mail/src/leap/mail/smtp/tests/test_gateway.py b/mail/src/leap/mail/smtp/tests/test_gateway.py
index aeace4a..8cbff8f 100644
--- a/mail/src/leap/mail/smtp/tests/test_gateway.py
+++ b/mail/src/leap/mail/smtp/tests/test_gateway.py
@@ -23,6 +23,7 @@ SMTP gateway tests.
 import re
 from datetime import datetime
 
+from twisted.internet.defer import inlineCallbacks, fail
 from twisted.test import proto_helpers
 
 from mock import Mock
@@ -34,7 +35,7 @@ from leap.mail.tests import (
     ADDRESS,
     ADDRESS_2,
 )
-from leap.keymanager import openpgp
+from leap.keymanager import openpgp, errors
 
 
 # some regexps
@@ -87,7 +88,8 @@ class TestSmtpGateway(TestCaseWithKeyManager):
         proto = SMTPFactory(
             u'anotheruser@leap.se',
             self._km,
-            self._config['encrypted_only'], outgoing_mail=Mock()).buildProtocol(('127.0.0.1', 0))
+            self._config['encrypted_only'],
+            outgoing_mail=Mock()).buildProtocol(('127.0.0.1', 0))
         # snip...
         transport = proto_helpers.StringTransport()
         proto.makeConnection(transport)
@@ -98,23 +100,26 @@ class TestSmtpGateway(TestCaseWithKeyManager):
                              'Did not get expected answer from gateway.')
         proto.setTimeout(None)
 
+    @inlineCallbacks
     def test_missing_key_rejects_address(self):
         """
         Test if server rejects to send unencrypted when 'encrypted_only' is
         True.
         """
         # remove key from key manager
-        pubkey = self._km.get_key(ADDRESS, openpgp.OpenPGPKey)
+        pubkey = yield self._km.get_key(ADDRESS, openpgp.OpenPGPKey)
         pgp = openpgp.OpenPGPScheme(
             self._soledad, gpgbinary=self.GPG_BINARY_PATH)
-        pgp.delete_key(pubkey)
+        yield pgp.delete_key(pubkey)
         # mock the key fetching
-        self._km.fetch_keys_from_server = Mock(return_value=[])
+        self._km._fetch_keys_from_server = Mock(
+            return_value=fail(errors.KeyNotFound()))
         # prepare the SMTP factory
         proto = SMTPFactory(
             u'anotheruser@leap.se',
             self._km,
-            self._config['encrypted_only'], outgoing_mail=Mock()).buildProtocol(('127.0.0.1', 0))
+            self._config['encrypted_only'],
+            outgoing_mail=Mock()).buildProtocol(('127.0.0.1', 0))
         transport = proto_helpers.StringTransport()
         proto.makeConnection(transport)
         proto.lineReceived(self.EMAIL_DATA[0] + '\r\n')
@@ -127,18 +132,20 @@ class TestSmtpGateway(TestCaseWithKeyManager):
             lines[-1],
             'Address should have been rejecetd with appropriate message.')
 
+    @inlineCallbacks
     def test_missing_key_accepts_address(self):
         """
         Test if server accepts to send unencrypted when 'encrypted_only' is
         False.
         """
         # remove key from key manager
-        pubkey = self._km.get_key(ADDRESS, openpgp.OpenPGPKey)
+        pubkey = yield self._km.get_key(ADDRESS, openpgp.OpenPGPKey)
         pgp = openpgp.OpenPGPScheme(
             self._soledad, gpgbinary=self.GPG_BINARY_PATH)
-        pgp.delete_key(pubkey)
+        yield pgp.delete_key(pubkey)
         # mock the key fetching
-        self._km.fetch_keys_from_server = Mock(return_value=[])
+        self._km._fetch_keys_from_server = Mock(
+            return_value=fail(errors.KeyNotFound()))
         # prepare the SMTP factory with encrypted only equal to false
         proto = SMTPFactory(
             u'anotheruser@leap.se',
diff --git a/mail/src/leap/mail/tests/__init__.py b/mail/src/leap/mail/tests/__init__.py
index 10bc5fe..b35107d 100644
--- a/mail/src/leap/mail/tests/__init__.py
+++ b/mail/src/leap/mail/tests/__init__.py
@@ -19,16 +19,14 @@ Base classes and keys for leap.mail tests.
 """
 import os
 import distutils.spawn
-import shutil
-import tempfile
 from mock import Mock
+from twisted.internet.defer import gatherResults
+from twisted.trial import unittest
 
 
 from leap.soledad.client import Soledad
-from leap.keymanager import (
-    KeyManager,
-    openpgp,
-)
+from leap.keymanager import KeyManager
+from leap.keymanager.openpgp import OpenPGPKey
 
 
 from leap.common.testing.basetest import BaseLeapTest
@@ -39,22 +37,12 @@ def _find_gpg():
     return os.path.realpath(gpg_path) if gpg_path is not None else "/usr/bin/gpg"
 
 
-class TestCaseWithKeyManager(BaseLeapTest):
+class TestCaseWithKeyManager(unittest.TestCase, BaseLeapTest):
 
     GPG_BINARY_PATH = _find_gpg()
 
     def setUp(self):
-        # mimic BaseLeapTest.setUpClass behaviour, because this is deprecated
-        # in Twisted: http://twistedmatrix.com/trac/ticket/1870
-        self.old_path = os.environ['PATH']
-        self.old_home = os.environ['HOME']
-        self.tempdir = tempfile.mkdtemp(prefix="leap_tests-")
-        self.home = self.tempdir
-        bin_tdir = os.path.join(
-            self.tempdir,
-            'bin')
-        os.environ["PATH"] = bin_tdir
-        os.environ["HOME"] = self.tempdir
+        self.setUpEnv()
 
         # setup our own stuff
         address = 'leap@leap.se'  # user's address in the form user@provider
@@ -65,36 +53,7 @@ class TestCaseWithKeyManager(BaseLeapTest):
         server_url = 'http://provider/'
         cert_file = ''
 
-        self._soledad = self._soledad_instance(
-            uuid, passphrase, secrets_path, local_db_path, server_url,
-            cert_file)
-        self._km = self._keymanager_instance(address)
-
-    def _soledad_instance(self, uuid, passphrase, secrets_path, local_db_path,
-                          server_url, cert_file):
-        """
-        Return a Soledad instance for tests.
-        """
-        # mock key fetching and storing so Soledad doesn't fail when trying to
-        # reach the server.
-        Soledad._fetch_keys_from_shared_db = Mock(return_value=None)
-        Soledad._assert_keys_in_shared_db = Mock(return_value=None)
-
-        # instantiate soledad
-        def _put_doc_side_effect(doc):
-            self._doc_put = doc
-
-        class MockSharedDB(object):
-
-            get_doc = Mock(return_value=None)
-            put_doc = Mock(side_effect=_put_doc_side_effect)
-            lock = Mock(return_value=('atoken', 300))
-            unlock = Mock(return_value=True)
-
-            def __call__(self):
-                return self
-
-        soledad = Soledad(
+        self._soledad = Soledad(
             uuid,
             passphrase,
             secrets_path=secrets_path,
@@ -103,13 +62,11 @@ class TestCaseWithKeyManager(BaseLeapTest):
             cert_file=cert_file,
             syncable=False
         )
+        return self._setup_keymanager(address)
 
-        soledad._shared_db = MockSharedDB()
-        return soledad
-
-    def _keymanager_instance(self, address):
+    def _setup_keymanager(self, address):
         """
-        Return a Key Manager instance for tests.
+        Set up Key Manager and return a Deferred that will be fired when done.
         """
         self._config = {
             'host': 'https://provider/',
@@ -132,26 +89,17 @@ class TestCaseWithKeyManager(BaseLeapTest):
                 pass
 
         nickserver_url = ''  # the url of the nickserver
-        km = KeyManager(address, nickserver_url, self._soledad,
-                        ca_cert_path='', gpgbinary=self.GPG_BINARY_PATH)
-        km._fetcher.put = Mock()
-        km._fetcher.get = Mock(return_value=Response())
-
-        # insert test keys in key manager.
-        pgp = openpgp.OpenPGPScheme(
-            self._soledad, gpgbinary=self.GPG_BINARY_PATH)
-        pgp.put_ascii_key(PRIVATE_KEY)
-        pgp.put_ascii_key(PRIVATE_KEY_2)
+        self._km = KeyManager(address, nickserver_url, self._soledad,
+                              ca_cert_path='', gpgbinary=self.GPG_BINARY_PATH)
+        self._km._fetcher.put = Mock()
+        self._km._fetcher.get = Mock(return_value=Response())
 
-        return km
+        d1 = self._km.put_raw_key(PRIVATE_KEY, OpenPGPKey, ADDRESS)
+        d2 = self._km.put_raw_key(PRIVATE_KEY_2, OpenPGPKey, ADDRESS_2)
+        return gatherResults([d1, d2])
 
     def tearDown(self):
-        # mimic LeapBaseTest.tearDownClass behaviour
-        os.environ["PATH"] = self.old_path
-        os.environ["HOME"] = self.old_home
-        # safety check
-        assert 'leap_tests-' in self.tempdir
-        shutil.rmtree(self.tempdir)
+        self.tearDownEnv()
 
 
 # Key material for testing
diff --git a/mail/src/leap/mail/tests/test_service.py b/mail/src/leap/mail/tests/test_service.py
index f0a807d..43f354d 100644
--- a/mail/src/leap/mail/tests/test_service.py
+++ b/mail/src/leap/mail/tests/test_service.py
@@ -22,7 +22,8 @@ SMTP gateway tests.
 
 import re
 from datetime import datetime
-from twisted.mail.smtp import User, Address
+from twisted.internet.defer import fail
+from twisted.mail.smtp import User
 
 from mock import Mock
 
@@ -33,7 +34,7 @@ from leap.mail.tests import (
     ADDRESS,
     ADDRESS_2,
 )
-from leap.keymanager import openpgp
+from leap.keymanager import openpgp, errors
 
 
 class TestOutgoingMail(TestCaseWithKeyManager):
@@ -54,71 +55,126 @@ class TestOutgoingMail(TestCaseWithKeyManager):
                   'QUIT']
 
     def setUp(self):
-        TestCaseWithKeyManager.setUp(self)
         self.lines = [line for line in self.EMAIL_DATA[4:12]]
         self.lines.append('')  # add a trailing newline
         self.raw = '\r\n'.join(self.lines)
+        self.expected_body = ('\r\n'.join(self.EMAIL_DATA[9:12]) +
+                              "\r\n\r\n--\r\nI prefer encrypted email - "
+                              "https://leap.se/key/anotheruser\r\n")
         self.fromAddr = ADDRESS_2
-        self.outgoing_mail = OutgoingMail(self.fromAddr, self._km, self._config['cert'], self._config['key'],
-                                        self._config['host'], self._config['port'])
-        self.proto = SMTPFactory(
-            u'anotheruser@leap.se',
-            self._km,
-            self._config['encrypted_only'],
-            self.outgoing_mail).buildProtocol(('127.0.0.1', 0))
-        self.dest = User(ADDRESS, 'gateway.leap.se', self.proto, ADDRESS)
-
-    def test_openpgp_encrypt_decrypt(self):
-        "Test if openpgp can encrypt and decrypt."
-        text = "simple raw text"
-        pubkey = self._km.get_key(
-            ADDRESS, openpgp.OpenPGPKey, private=False)
-        encrypted = self._km.encrypt(text, pubkey)
-        self.assertNotEqual(
-            text, encrypted, "Ciphertext is equal to plaintext.")
-        privkey = self._km.get_key(
-            ADDRESS, openpgp.OpenPGPKey, private=True)
-        decrypted = self._km.decrypt(encrypted, privkey)
-        self.assertEqual(text, decrypted,
-                         "Decrypted text differs from plaintext.")
+
+        def init_outgoing_and_proto(_):
+            self.outgoing_mail = OutgoingMail(
+                self.fromAddr, self._km, self._config['cert'],
+                self._config['key'], self._config['host'],
+                self._config['port'])
+            self.proto = SMTPFactory(
+                u'anotheruser@leap.se',
+                self._km,
+                self._config['encrypted_only'],
+                self.outgoing_mail).buildProtocol(('127.0.0.1', 0))
+            self.dest = User(ADDRESS, 'gateway.leap.se', self.proto, ADDRESS)
+
+        d = TestCaseWithKeyManager.setUp(self)
+        d.addCallback(init_outgoing_and_proto)
+        return d
 
     def test_message_encrypt(self):
         """
         Test if message gets encrypted to destination email.
         """
-
-        message, _ = self.outgoing_mail._maybe_encrypt_and_sign(self.raw, self.dest)
-
-        # assert structure of encrypted message
-        self.assertTrue('Content-Type' in message)
-        self.assertEqual('multipart/encrypted', message.get_content_type())
-        self.assertEqual('application/pgp-encrypted',
-                         message.get_param('protocol'))
-        self.assertEqual(2, len(message.get_payload()))
-        self.assertEqual('application/pgp-encrypted',
-                         message.get_payload(0).get_content_type())
-        self.assertEqual('application/octet-stream',
-                         message.get_payload(1).get_content_type())
-        privkey = self._km.get_key(
-            ADDRESS, openpgp.OpenPGPKey, private=True)
-        decrypted = self._km.decrypt(
-            message.get_payload(1).get_payload(), privkey)
-
-        expected = '\n' + '\r\n'.join(
-            self.EMAIL_DATA[9:12]) + '\r\n\r\n--\r\n' + 'I prefer encrypted email - https://leap.se/key/anotheruser\r\n'
-        self.assertEqual(
-            expected,
-            decrypted,
-            'Decrypted text differs from plaintext.')
+        def check_decryption(res):
+            decrypted, _ = res
+            self.assertEqual(
+                '\n' + self.expected_body,
+                decrypted,
+                'Decrypted text differs from plaintext.')
+
+        d = self.outgoing_mail._maybe_encrypt_and_sign(self.raw, self.dest)
+        d.addCallback(self._assert_encrypted)
+        d.addCallback(lambda message: self._km.decrypt(
+            message.get_payload(1).get_payload(), ADDRESS, openpgp.OpenPGPKey))
+        d.addCallback(check_decryption)
+        return d
 
     def test_message_encrypt_sign(self):
         """
         Test if message gets encrypted to destination email and signed with
         sender key.
-        """
-        message, _ = self.outgoing_mail._maybe_encrypt_and_sign(self.raw, self.dest)
+        '"""
+        def check_decryption_and_verify(res):
+            decrypted, signkey = res
+            self.assertEqual(
+                '\n' + self.expected_body,
+                decrypted,
+                'Decrypted text differs from plaintext.')
+            self.assertTrue(ADDRESS_2 in signkey.address,
+                            "Verification failed")
+
+        d = self.outgoing_mail._maybe_encrypt_and_sign(self.raw, self.dest)
+        d.addCallback(self._assert_encrypted)
+        d.addCallback(lambda message: self._km.decrypt(
+            message.get_payload(1).get_payload(), ADDRESS, openpgp.OpenPGPKey,
+            verify=ADDRESS_2))
+        d.addCallback(check_decryption_and_verify)
+        return d
 
-        # assert structure of encrypted message
+    def test_message_sign(self):
+        """
+        Test if message is signed with sender key.
+        """
+        # mock the key fetching
+        self._km._fetch_keys_from_server = Mock(
+            return_value=fail(errors.KeyNotFound()))
+        recipient = User('ihavenopubkey@nonleap.se',
+                         'gateway.leap.se', self.proto, ADDRESS)
+        self.outgoing_mail = OutgoingMail(
+            self.fromAddr, self._km, self._config['cert'], self._config['key'],
+            self._config['host'], self._config['port'])
+
+        def check_signed(res):
+            message, _ = res
+            self.assertTrue('Content-Type' in message)
+            self.assertEqual('multipart/signed', message.get_content_type())
+            self.assertEqual('application/pgp-signature',
+                             message.get_param('protocol'))
+            self.assertEqual('pgp-sha512', message.get_param('micalg'))
+            # assert content of message
+            self.assertEqual(self.expected_body,
+                             message.get_payload(0).get_payload(decode=True))
+            # assert content of signature
+            self.assertTrue(
+                message.get_payload(1).get_payload().startswith(
+                    '-----BEGIN PGP SIGNATURE-----\n'),
+                'Message does not start with signature header.')
+            self.assertTrue(
+                message.get_payload(1).get_payload().endswith(
+                    '-----END PGP SIGNATURE-----\n'),
+                'Message does not end with signature footer.')
+            return message
+
+        def verify(message):
+            # replace EOL before verifying (according to rfc3156)
+            signed_text = re.sub('\r?\n', '\r\n',
+                                 message.get_payload(0).as_string())
+
+            def assert_verify(key):
+                self.assertTrue(ADDRESS_2 in key.address,
+                                 'Signature could not be verified.')
+
+            d = self._km.verify(
+                signed_text, ADDRESS_2, openpgp.OpenPGPKey,
+                detached_sig=message.get_payload(1).get_payload())
+            d.addCallback(assert_verify)
+            return d
+
+        d = self.outgoing_mail._maybe_encrypt_and_sign(self.raw, recipient)
+        d.addCallback(check_signed)
+        d.addCallback(verify)
+        return d
+
+    def _assert_encrypted(self, res):
+        message, _ = res
         self.assertTrue('Content-Type' in message)
         self.assertEqual('multipart/encrypted', message.get_content_type())
         self.assertEqual('application/pgp-encrypted',
@@ -128,58 +184,4 @@ class TestOutgoingMail(TestCaseWithKeyManager):
                          message.get_payload(0).get_content_type())
         self.assertEqual('application/octet-stream',
                          message.get_payload(1).get_content_type())
-        # decrypt and verify
-        privkey = self._km.get_key(
-            ADDRESS, openpgp.OpenPGPKey, private=True)
-        pubkey = self._km.get_key(ADDRESS_2, openpgp.OpenPGPKey)
-        decrypted = self._km.decrypt(
-            message.get_payload(1).get_payload(), privkey, verify=pubkey)
-        self.assertEqual(
-            '\n' + '\r\n'.join(self.EMAIL_DATA[9:12]) + '\r\n\r\n--\r\n' +
-            'I prefer encrypted email - https://leap.se/key/anotheruser\r\n',
-            decrypted,
-            'Decrypted text differs from plaintext.')
-
-    def test_message_sign(self):
-        """
-        Test if message is signed with sender key.
-        """
-        # mock the key fetching
-        self._km.fetch_keys_from_server = Mock(return_value=[])
-        recipient = User('ihavenopubkey@nonleap.se',
-                    'gateway.leap.se', self.proto, ADDRESS)
-        self.outgoing_mail = OutgoingMail(self.fromAddr, self._km, self._config['cert'], self._config['key'],
-                                        self._config['host'], self._config['port'])
-
-        message, _ = self.outgoing_mail._maybe_encrypt_and_sign(self.raw, recipient)
-
-        # assert structure of signed message
-        self.assertTrue('Content-Type' in message)
-        self.assertEqual('multipart/signed', message.get_content_type())
-        self.assertEqual('application/pgp-signature',
-                         message.get_param('protocol'))
-        self.assertEqual('pgp-sha512', message.get_param('micalg'))
-        # assert content of message
-        self.assertEqual(
-            '\r\n'.join(self.EMAIL_DATA[9:13]) + '\r\n--\r\n' +
-            'I prefer encrypted email - https://leap.se/key/anotheruser\r\n',
-            message.get_payload(0).get_payload(decode=True))
-        # assert content of signature
-        self.assertTrue(
-            message.get_payload(1).get_payload().startswith(
-                '-----BEGIN PGP SIGNATURE-----\n'),
-            'Message does not start with signature header.')
-        self.assertTrue(
-            message.get_payload(1).get_payload().endswith(
-                '-----END PGP SIGNATURE-----\n'),
-            'Message does not end with signature footer.')
-        # assert signature is valid
-        pubkey = self._km.get_key(ADDRESS_2, openpgp.OpenPGPKey)
-        # replace EOL before verifying (according to rfc3156)
-        signed_text = re.sub('\r?\n', '\r\n',
-                             message.get_payload(0).as_string())
-        self.assertTrue(
-            self._km.verify(signed_text,
-                            pubkey,
-                            detached_sig=message.get_payload(1).get_payload()),
-            'Signature could not be verified.')
+        return message