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-rw-r--r--mail/changes/feature_3878_add-preference-to-openpgp-header2
-rw-r--r--mail/changes/feature_4354_add-signature-header-to-incoming-email2
-rw-r--r--mail/changes/feature_4526_add-footer-to-outgoing-email2
-rw-r--r--mail/src/leap/mail/imap/fetch.py268
-rw-r--r--mail/src/leap/mail/imap/tests/test_imap.py18
-rw-r--r--mail/src/leap/mail/smtp/gateway.py14
-rw-r--r--mail/src/leap/mail/smtp/tests/__init__.py4
-rw-r--r--mail/src/leap/mail/smtp/tests/test_gateway.py21
8 files changed, 233 insertions, 98 deletions
diff --git a/mail/changes/feature_3878_add-preference-to-openpgp-header b/mail/changes/feature_3878_add-preference-to-openpgp-header
new file mode 100644
index 00000000..4513bf6a
--- /dev/null
+++ b/mail/changes/feature_3878_add-preference-to-openpgp-header
@@ -0,0 +1,2 @@
+ o Add 'signencrypt' preference to OpenPGP header on outgoing email. Closes
+ #3878".
diff --git a/mail/changes/feature_4354_add-signature-header-to-incoming-email b/mail/changes/feature_4354_add-signature-header-to-incoming-email
new file mode 100644
index 00000000..866b68ef
--- /dev/null
+++ b/mail/changes/feature_4354_add-signature-header-to-incoming-email
@@ -0,0 +1,2 @@
+ o Add a header to incoming emails that reflects if a valid signature was
+ found when decrypting. Closes #4354.
diff --git a/mail/changes/feature_4526_add-footer-to-outgoing-email b/mail/changes/feature_4526_add-footer-to-outgoing-email
new file mode 100644
index 00000000..60308add
--- /dev/null
+++ b/mail/changes/feature_4526_add-footer-to-outgoing-email
@@ -0,0 +1,2 @@
+ o Add a footer to outgoing email pointing to the address where sender keys
+ can be fetched. Closes #4526.
diff --git a/mail/src/leap/mail/imap/fetch.py b/mail/src/leap/mail/imap/fetch.py
index 3422ed50..38612e1e 100644
--- a/mail/src/leap/mail/imap/fetch.py
+++ b/mail/src/leap/mail/imap/fetch.py
@@ -22,8 +22,12 @@ import json
import ssl
import threading
import time
+import copy
+from StringIO import StringIO
from email.parser import Parser
+from email.generator import Generator
+from email.utils import parseaddr
from twisted.python import log
from twisted.internet.task import LoopingCall
@@ -65,6 +69,16 @@ class LeapIncomingMail(object):
INCOMING_KEY = "incoming"
CONTENT_KEY = "content"
+ LEAP_SIGNATURE_HEADER = 'X-Leap-Signature'
+ """
+ Header added to messages when they are decrypted by the IMAP fetcher,
+ which states the validity of an eventual signature that might be included
+ in the encrypted blob.
+ """
+ LEAP_SIGNATURE_VALID = 'valid'
+ LEAP_SIGNATURE_INVALID = 'invalid'
+ LEAP_SIGNATURE_COULD_NOT_VERIFY = 'could not verify'
+
fetching_lock = threading.Lock()
def __init__(self, keymanager, soledad, imap_account,
@@ -260,11 +274,9 @@ class LeapIncomingMail(object):
if self._is_msg(keys):
# Ok, this looks like a legit msg.
# Let's process it!
- encdata = doc.content[ENC_JSON_KEY]
-
# Deferred chain for individual messages
- d = deferToThread(self._decrypt_msg, doc, encdata)
- d.addCallback(self._process_decrypted)
+ d = deferToThread(self._decrypt_doc, doc)
+ d.addCallback(self._process_decrypted_doc)
d.addErrback(self._log_err)
d.addCallback(self._add_message_locally)
d.addErrback(self._log_err)
@@ -293,32 +305,40 @@ class LeapIncomingMail(object):
"""
return ENC_SCHEME_KEY in keys and ENC_JSON_KEY in keys
- def _decrypt_msg(self, doc, encdata):
+ def _decrypt_doc(self, doc):
+ """
+ Decrypt the contents of a document.
+
+ :param doc: A document containing an encrypted message.
+ :type doc: SoledadDocument
+
+ :return: A tuple containing the document and the decrypted message.
+ :rtype: (SoledadDocument, str)
+ """
log.msg('decrypting msg')
- key = self._pkey
+ success = False
try:
- decrdata = (self._keymanager.decrypt(
- encdata, key,
- passphrase=self._soledad.passphrase))
- ok = True
+ decrdata = self._keymanager.decrypt(
+ doc.content[ENC_JSON_KEY],
+ self._pkey)
+ success = True
except Exception as exc:
# XXX move this to errback !!!
logger.warning("Error while decrypting msg: %r" % (exc,))
decrdata = ""
- ok = False
- leap_events.signal(IMAP_MSG_DECRYPTED, "1" if ok else "0")
+ leap_events.signal(IMAP_MSG_DECRYPTED, "1" if success else "0")
return doc, decrdata
- def _process_decrypted(self, msgtuple):
+ def _process_decrypted_doc(self, msgtuple):
"""
- Process a successfully decrypted message.
+ 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)
- :returns: a SoledadDocument and the processed data.
+ :return: a SoledadDocument and the processed data.
:rtype: (doc, data)
"""
doc, data = msgtuple
@@ -333,13 +353,13 @@ class LeapIncomingMail(object):
if not rawmsg:
return False
try:
- data = self._maybe_decrypt_gpg_msg(rawmsg)
+ data = self._maybe_decrypt_msg(rawmsg)
return doc, data
except keymanager_errors.EncryptionDecryptionFailed as exc:
logger.error(exc)
raise
- def _maybe_decrypt_gpg_msg(self, data):
+ def _maybe_decrypt_msg(self, data):
"""
Tries to decrypt a gpg message if data looks like one.
@@ -348,80 +368,168 @@ class LeapIncomingMail(object):
:return: data, possibly descrypted.
:rtype: str
"""
- # TODO split this method
leap_assert_type(data, unicode)
+ # parse the original message
parser = Parser()
encoding = get_email_charset(data)
data = data.encode(encoding)
- origmsg = parser.parsestr(data)
-
- # handle multipart/encrypted messages
- if origmsg.get_content_type() == 'multipart/encrypted':
- # sanity check
- payload = origmsg.get_payload()
- if len(payload) != 2:
- raise MalformedMessage(
- 'Multipart/encrypted messages should have exactly 2 body '
- 'parts (instead of %d).' % len(payload))
- if payload[0].get_content_type() != 'application/pgp-encrypted':
- raise MalformedMessage(
- "Multipart/encrypted messages' first body part should "
- "have content type equal to 'application/pgp-encrypted' "
- "(instead of %s)." % payload[0].get_content_type())
- if payload[1].get_content_type() != 'application/octet-stream':
- raise MalformedMessage(
- "Multipart/encrypted messages' second body part should "
- "have content type equal to 'octet-stream' (instead of "
- "%s)." % payload[1].get_content_type())
-
- # parse message and get encrypted content
- pgpencmsg = origmsg.get_payload()[1]
- encdata = pgpencmsg.get_payload()
-
- # decrypt and parse decrypted message
- decrdata = self._keymanager.decrypt(
- encdata, self._pkey,
- passphrase=self._soledad.passphrase)
+ msg = parser.parsestr(data)
+
+ # try to obtain sender public key
+ senderPubkey = None
+ fromHeader = msg.get('from', None)
+ if fromHeader is not None:
+ _, senderAddress = parseaddr(fromHeader)
try:
- decrdata = decrdata.encode(encoding)
- except (UnicodeEncodeError, UnicodeDecodeError) as e:
- logger.error("Unicode error {0}".format(e))
- decrdata = decrdata.encode(encoding, 'replace')
-
- decrmsg = parser.parsestr(decrdata)
- # remove original message's multipart/encrypted content-type
- del(origmsg['content-type'])
- # replace headers back in original message
- for hkey, hval in decrmsg.items():
- try:
- # this will raise KeyError if header is not present
- origmsg.replace_header(hkey, hval)
- except KeyError:
- origmsg[hkey] = hval
-
- # replace payload by unencrypted payload
- origmsg.set_payload(decrmsg.get_payload())
- return origmsg.as_string(unixfrom=False)
+ 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
+ decrdata = ''
+ if msg.get_content_type() == 'multipart/encrypted':
+ decrmsg, valid_sig = self._decrypt_multipart_encrypted_msg(
+ msg, encoding, senderPubkey)
+ else:
+ decrmsg, valid_sig = self._maybe_decrypt_inline_encrypted_msg(
+ 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:
- PGP_BEGIN = "-----BEGIN PGP MESSAGE-----"
- PGP_END = "-----END PGP MESSAGE-----"
- # handle inline PGP messages
- if PGP_BEGIN in data:
- begin = data.find(PGP_BEGIN)
- end = data.rfind(PGP_END)
- pgp_message = data[begin:begin+end]
- decrdata = (self._keymanager.decrypt(
- pgp_message, self._pkey,
- passphrase=self._soledad.passphrase))
- # replace encrypted by decrypted content
- data = data.replace(pgp_message, decrdata)
+ 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()
+
+ def _decrypt_multipart_encrypted_msg(self, msg, encoding, senderPubkey):
+ """
+ Decrypt a message with content-type 'multipart/encrypted'.
+
+ :param msg: The original encrypted message.
+ :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
+
+ :return: A unitary tuple containing a decrypted message.
+ :rtype: (Message)
+ """
+ msg = copy.deepcopy(msg)
+ # sanity check
+ payload = msg.get_payload()
+ if len(payload) != 2:
+ raise MalformedMessage(
+ 'Multipart/encrypted messages should have exactly 2 body '
+ 'parts (instead of %d).' % len(payload))
+ if payload[0].get_content_type() != 'application/pgp-encrypted':
+ raise MalformedMessage(
+ "Multipart/encrypted messages' first body part should "
+ "have content type equal to 'application/pgp-encrypted' "
+ "(instead of %s)." % payload[0].get_content_type())
+ if payload[1].get_content_type() != 'application/octet-stream':
+ raise MalformedMessage(
+ "Multipart/encrypted messages' second body part should "
+ "have content type equal to 'octet-stream' (instead of "
+ "%s)." % payload[1].get_content_type())
+ # parse message and get encrypted content
+ pgpencmsg = msg.get_payload()[1]
+ encdata = pgpencmsg.get_payload()
+ # decrypt and parse decrypted message
+ decrdata, valid_sig = self._decrypt_and_verify_data(
+ encdata, senderPubkey)
+ try:
+ decrdata = decrdata.encode(encoding)
+ except (UnicodeEncodeError, UnicodeDecodeError) as e:
+ logger.error("Unicode error {0}".format(e))
+ decrdata = decrdata.encode(encoding, 'replace')
+ parser = Parser()
+ decrmsg = 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 payload by unencrypted payload
+ msg.set_payload(decrmsg.get_payload())
+ return msg, valid_sig
+
+ def _maybe_decrypt_inline_encrypted_msg(self, origmsg, encoding,
+ senderPubkey):
+ """
+ Possibly decrypt an inline OpenPGP encrypted message.
+
+ :param origmsg: The original, possibly encrypted message.
+ :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
+
+ :return: A unitary tuple containing a decrypted message.
+ :rtype: (Message)
+ """
+ # serialize the original message
+ buf = StringIO()
+ g = Generator(buf)
+ g.flatten(origmsg)
+ data = buf.getvalue()
+ # handle exactly one inline PGP message
+ PGP_BEGIN = "-----BEGIN PGP MESSAGE-----"
+ PGP_END = "-----END 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)]
+ decrdata, valid_sig = self._decrypt_and_verify_data(
+ pgp_message, senderPubkey)
+ # replace encrypted by decrypted content
+ data = data.replace(pgp_message, decrdata)
# if message is not encrypted, return raw data
-
if isinstance(data, unicode):
data = data.encode(encoding, 'replace')
+ parser = Parser()
+ return parser.parsestr(data), valid_sig
+
+ def _decrypt_and_verify_data(self, data, senderPubkey):
+ """
+ Decrypt C{data} using our private key and attempt to verify a
+ signature using C{senderPubkey}.
- return data
+ :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)
+ """
+ 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
def _add_message_locally(self, msgtuple):
"""
diff --git a/mail/src/leap/mail/imap/tests/test_imap.py b/mail/src/leap/mail/imap/tests/test_imap.py
index ad11315d..ca73a11c 100644
--- a/mail/src/leap/mail/imap/tests/test_imap.py
+++ b/mail/src/leap/mail/imap/tests/test_imap.py
@@ -923,7 +923,6 @@ class LeapIMAP4ServerTestCase(IMAP4HelperMixin, unittest.TestCase):
"""
self.server.theAccount.addMailbox('test-mailbox-e',
creation_ts=42)
- #import ipdb; ipdb.set_trace()
self.examinedArgs = None
@@ -1108,16 +1107,15 @@ class LeapIMAP4ServerTestCase(IMAP4HelperMixin, unittest.TestCase):
mb = SimpleLEAPServer.theAccount.getMailbox('ROOT/SUBTHING')
self.assertEqual(1, len(mb.messages))
- #import ipdb; ipdb.set_trace()
self.assertEqual(
['\\SEEN', '\\DELETED'],
- mb.messages[1]['flags'])
+ mb.messages[1].content['flags'])
self.assertEqual(
'Tue, 17 Jun 2003 11:22:16 -0600 (MDT)',
- mb.messages[1]['date'])
+ mb.messages[1].content['date'])
- self.assertEqual(open(infile).read(), mb.messages[1]['raw'])
+ self.assertEqual(open(infile).read(), mb.messages[1].content['raw'])
def testPartialAppend(self):
"""
@@ -1152,11 +1150,11 @@ class LeapIMAP4ServerTestCase(IMAP4HelperMixin, unittest.TestCase):
self.assertEqual(1, len(mb.messages))
self.assertEqual(
['\\SEEN',],
- mb.messages[1]['flags']
+ mb.messages[1].content['flags']
)
self.assertEqual(
- 'Right now', mb.messages[1]['date'])
- self.assertEqual(open(infile).read(), mb.messages[1]['raw'])
+ 'Right now', mb.messages[1].content['date'])
+ self.assertEqual(open(infile).read(), mb.messages[1].content['raw'])
def testCheck(self):
"""
@@ -1214,7 +1212,7 @@ class LeapIMAP4ServerTestCase(IMAP4HelperMixin, unittest.TestCase):
def _cbTestClose(self, ignored, m):
self.assertEqual(len(m.messages), 1)
self.assertEqual(
- m.messages[1]['subject'],
+ m.messages[1].content['subject'],
'Message 2')
self.failUnless(m.closed)
@@ -1257,7 +1255,7 @@ class LeapIMAP4ServerTestCase(IMAP4HelperMixin, unittest.TestCase):
def _cbTestExpunge(self, ignored, m):
self.assertEqual(len(m.messages), 1)
self.assertEqual(
- m.messages[1]['subject'],
+ m.messages[1].content['subject'],
'Message 2')
self.assertEqual(self.results, [0, 1])
# XXX fix this thing with the indexes...
diff --git a/mail/src/leap/mail/smtp/gateway.py b/mail/src/leap/mail/smtp/gateway.py
index f09ee141..a78bd55b 100644
--- a/mail/src/leap/mail/smtp/gateway.py
+++ b/mail/src/leap/mail/smtp/gateway.py
@@ -333,6 +333,8 @@ class EncryptedMessage(object):
"""
implements(smtp.IMessage)
+ FOOTER_STRING = "I prefer encrypted email"
+
def __init__(self, fromAddress, user, keymanager, host, port, cert, key):
"""
Initialize the encrypted message.
@@ -597,7 +599,16 @@ class EncryptedMessage(object):
self._msg = self._origmsg
return
+ # add a nice footer to the outgoing message
from_address = validate_address(self._fromAddress.addrstr)
+ username, domain = from_address.split('@')
+ self.lines.append('--')
+ self.lines.append('%s - https://%s/key/%s.' %
+ (self.FOOTER_STRING, domain, username))
+ self.lines.append('')
+ self._origmsg = self.parseMessage()
+
+ # get sender and recipient data
signkey = self._km.get_key(from_address, OpenPGPKey, private=True)
log.msg("Will sign the message with %s." % signkey.fingerprint)
to_address = validate_address(self._user.dest.addrstr)
@@ -672,6 +683,7 @@ class EncryptedMessage(object):
username, domain = signkey.address.split('@')
newmsg.add_header(
'OpenPGP', 'id=%s' % signkey.key_id,
- url='https://%s/openpgp/%s' % (domain, username))
+ url='https://%s/key/%s' % (domain, username),
+ preference='signencrypt')
# delete user-agent from origmsg
del(origmsg['user-agent'])
diff --git a/mail/src/leap/mail/smtp/tests/__init__.py b/mail/src/leap/mail/smtp/tests/__init__.py
index 62b015f0..1459cea6 100644
--- a/mail/src/leap/mail/smtp/tests/__init__.py
+++ b/mail/src/leap/mail/smtp/tests/__init__.py
@@ -115,8 +115,8 @@ class TestCaseWithKeyManager(BaseLeapTest):
'username': address,
'password': '<password>',
'encrypted_only': True,
- 'cert': 'src/leap/mail/smtp/tests/cert/server.crt',
- 'key': 'src/leap/mail/smtp/tests/cert/server.key',
+ 'cert': u'src/leap/mail/smtp/tests/cert/server.crt',
+ 'key': u'src/leap/mail/smtp/tests/cert/server.key',
}
class Response(object):
diff --git a/mail/src/leap/mail/smtp/tests/test_gateway.py b/mail/src/leap/mail/smtp/tests/test_gateway.py
index f9ea027c..4c2f04f4 100644
--- a/mail/src/leap/mail/smtp/tests/test_gateway.py
+++ b/mail/src/leap/mail/smtp/tests/test_gateway.py
@@ -22,7 +22,6 @@ SMTP gateway tests.
import re
-
from datetime import datetime
from gnupg._util import _make_binary_stream
from twisted.test import proto_helpers
@@ -131,6 +130,9 @@ class TestSmtpGateway(TestCaseWithKeyManager):
for line in self.EMAIL_DATA[4:12]:
m.lineReceived(line)
m.eomReceived()
+ # we need to call the following explicitelly because it was deferred
+ # inside the previous method
+ m._maybe_encrypt_and_sign()
# assert structure of encrypted message
self.assertTrue('Content-Type' in m._msg)
self.assertEqual('multipart/encrypted', m._msg.get_content_type())
@@ -146,7 +148,8 @@ class TestSmtpGateway(TestCaseWithKeyManager):
decrypted = self._km.decrypt(
m._msg.get_payload(1).get_payload(), privkey)
self.assertEqual(
- '\n' + '\r\n'.join(self.EMAIL_DATA[9:12]) + '\r\n',
+ '\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.')
@@ -168,6 +171,9 @@ class TestSmtpGateway(TestCaseWithKeyManager):
m.lineReceived(line)
# trigger encryption and signing
m.eomReceived()
+ # we need to call the following explicitelly because it was deferred
+ # inside the previous method
+ m._maybe_encrypt_and_sign()
# assert structure of encrypted message
self.assertTrue('Content-Type' in m._msg)
self.assertEqual('multipart/encrypted', m._msg.get_content_type())
@@ -185,7 +191,8 @@ class TestSmtpGateway(TestCaseWithKeyManager):
decrypted = self._km.decrypt(
m._msg.get_payload(1).get_payload(), privkey, verify=pubkey)
self.assertEqual(
- '\n' + '\r\n'.join(self.EMAIL_DATA[9:12]) + '\r\n',
+ '\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.')
@@ -208,6 +215,9 @@ class TestSmtpGateway(TestCaseWithKeyManager):
m.lineReceived(line)
# trigger signing
m.eomReceived()
+ # we need to call the following explicitelly because it was deferred
+ # inside the previous method
+ m._maybe_encrypt_and_sign()
# assert structure of signed message
self.assertTrue('Content-Type' in m._msg)
self.assertEqual('multipart/signed', m._msg.get_content_type())
@@ -216,8 +226,9 @@ class TestSmtpGateway(TestCaseWithKeyManager):
self.assertEqual('pgp-sha512', m._msg.get_param('micalg'))
# assert content of message
self.assertEqual(
- m._msg.get_payload(0).get_payload(decode=True),
- '\r\n'.join(self.EMAIL_DATA[9:13]))
+ '\r\n'.join(self.EMAIL_DATA[9:13])+'\r\n--\r\n' +
+ 'I prefer encrypted email - https://leap.se/key/anotheruser.\r\n',
+ m._msg.get_payload(0).get_payload(decode=True))
# assert content of signature
self.assertTrue(
m._msg.get_payload(1).get_payload().startswith(
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 06:20:38 +0000