Support for PKIX over Secure HTTP (POSH)

Fixes #9083
This commit is contained in:
Philipp Hörist 2018-05-01 20:32:36 +02:00
parent 8d0815c176
commit bcf27cb3c1
5 changed files with 142 additions and 63 deletions

View File

@ -409,6 +409,7 @@ class Config:
'recent_groupchats': [ opt_str, '' ],
'httpupload_verify': [ opt_bool, True, _('HTTP Upload: Enable HTTPS Verification')],
'filetransfer_preference' : [ opt_str, 'httpupload', _('Preferred file transfer mechanism for file drag&drop on chat window. Can be \'httpupload\' (default) or \'jingle\'')],
'allow_posh': [ opt_bool, True, _('Allow cert verification with POSH')],
}, {}),
'statusmsg': ({
'message': [ opt_str, '' ],

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@ -43,8 +43,11 @@ import hmac
import hashlib
import json
import logging
import base64
from functools import partial
from string import Template
from urllib.request import urlopen
from urllib.error import URLError
try:
randomsource = random.SystemRandom()
@ -75,42 +78,6 @@ from gajim.gtkgui_helpers import get_action
log = logging.getLogger('gajim.c.connection')
ssl_error = {
2: _("Unable to get issuer certificate"),
3: _("Unable to get certificate CRL"),
4: _("Unable to decrypt certificate's signature"),
5: _("Unable to decrypt CRL's signature"),
6: _("Unable to decode issuer public key"),
7: _("Certificate signature failure"),
8: _("CRL signature failure"),
9: _("Certificate is not yet valid"),
10: _("Certificate has expired"),
11: _("CRL is not yet valid"),
12: _("CRL has expired"),
13: _("Format error in certificate's notBefore field"),
14: _("Format error in certificate's notAfter field"),
15: _("Format error in CRL's lastUpdate field"),
16: _("Format error in CRL's nextUpdate field"),
17: _("Out of memory"),
18: _("Self signed certificate"),
19: _("Self signed certificate in certificate chain"),
20: _("Unable to get local issuer certificate"),
21: _("Unable to verify the first certificate"),
22: _("Certificate chain too long"),
23: _("Certificate revoked"),
24: _("Invalid CA certificate"),
25: _("Path length constraint exceeded"),
26: _("Unsupported certificate purpose"),
27: _("Certificate not trusted"),
28: _("Certificate rejected"),
29: _("Subject issuer mismatch"),
30: _("Authority and subject key identifier mismatch"),
31: _("Authority and issuer serial number mismatch"),
32: _("Key usage does not include certificate signing"),
50: _("Application verification failure")
#100 is for internal usage: host not correct
}
SERVICE_START_TLS = 'xmpp-client'
SERVICE_DIRECT_TLS = 'xmpps-client'
@ -693,6 +660,13 @@ class Connection(CommonConnection, ConnectionHandlers):
self.secret_hmac = str(random.random())[2:].encode('utf-8')
self.removing_account = False
# We only request POSH once
self._posh_requested = False
# Fingerprints received via POSH
self._posh_hashes = []
# The SSL Errors that we can override with POSH
self._posh_errors = [18, 19]
self.sm = Smacks(self) # Stream Management
app.ged.register_event_handler('privacy-list-received', ged.CORE,
@ -1374,25 +1348,85 @@ class Connection(CommonConnection, ConnectionHandlers):
cert = self.connection.Connection.ssl_certificate
errnum = self._ssl_errors.pop()
hostname = app.config.get_per('accounts', self.name, 'hostname')
text = _('The authenticity of the %s '
'certificate could be invalid') % hostname
if errnum in ssl_error:
text += _('\nSSL Error: <b>%s</b>') % ssl_error[errnum]
else:
text += _('\nUnknown SSL error: %d') % errnum
fingerprint_sha1 = cert.digest('sha1').decode('utf-8')
fingerprint_sha256 = cert.digest('sha256').decode('utf-8')
pem = OpenSSL.crypto.dump_certificate(
OpenSSL.crypto.FILETYPE_PEM, cert).decode('utf-8')
app.nec.push_incoming_event(
SSLErrorEvent(None, conn=self,
error_text=text,
error_num=errnum,
cert=pem,
fingerprint_sha1=fingerprint_sha1,
fingerprint_sha256=fingerprint_sha256,
certificate=cert))
# Check if we can verify the cert with POSH
if errnum in self._posh_errors:
# Request the POSH json file
self._get_posh_file(self._hostname)
self._posh_requested = True
cert_hash256 = self._calculate_cert_sha256(cert)
print(cert_hash256)
if cert_hash256 in self._posh_hashes:
# Ignore this error if this cert is
# verifyed with POSH
self.process_ssl_errors()
return
app.nec.push_incoming_event(SSLErrorEvent(None, conn=self,
error_num=errnum,
cert=cert))
@staticmethod
def _calculate_cert_sha256(cert):
der_encoded = OpenSSL.crypto.dump_certificate(
OpenSSL.crypto.FILETYPE_ASN1, cert)
hash_obj = hashlib.sha256(der_encoded)
hash256 = base64.b64encode(hash_obj.digest()).decode('utf8')
return hash256
def _get_posh_file(self, hostname=None, redirect=None):
if self._posh_requested:
# We already have requested POSH
return
if not app.config.get_per('accounts', self.name, 'allow_posh'):
return
if hostname is None and redirect is None:
raise ValueError('There must be either a hostname or a url')
url = redirect
if hostname is not None:
url = 'https://%s/.well-known/posh/xmpp-client.json' % hostname
cafile = None
if os.name == 'nt':
cafile = certifi.where()
log.info('Request POSH from %s', url)
try:
file = urlopen(
url, cafile=cafile, timeout=2)
except URLError as exc:
log.info('Error while requesting POSH: %s' % exc)
return
if file.getcode() != 200:
log.info('No POSH file found at %s', url)
return
try:
posh = json.loads(file.read())
except json.decoder.JSONDecodeError as json_error:
log.warning(json_error)
return
# Redirect
if 'url' in posh and redirect is None:
# We dont allow redirects in redirects
log.info('POSH redirect found')
self._get_posh_file(redirect=posh['url'])
return
if 'fingerprints' in posh:
fingerprints = posh['fingerprints']
for fingerprint in fingerprints:
if 'sha-256' not in fingerprint:
continue
self._posh_hashes.append(fingerprint['sha-256'])
log.info('POSH sha-256 fingerprints found: %s',
self._posh_hashes)
def ssl_certificate_accepted(self):
if not self.connection:

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@ -42,7 +42,7 @@ from gajim.common import i18n
from gajim.common import dataforms
from gajim.common import configpaths
from gajim.common.zeroconf.zeroconf import Constant
from gajim.common.const import KindConstant
from gajim.common.const import KindConstant, SSLError
from gajim.common.pep import SUPPORTED_PERSONAL_USER_EVENTS
from gajim.common.jingle_transport import JingleTransportSocks5
from gajim.common.file_props import FilesProp
@ -1985,8 +1985,7 @@ class NewAccountConnectedEvent(nec.NetworkIncomingEvent):
self.errnum = 0 # we don't have an errnum
self.ssl_msg = ''
if self.errnum > 0:
from gajim.common.connection import ssl_error
self.ssl_msg = ssl_error.get(self.errnum,
self.ssl_msg = SSLError.get(self.errnum,
_('Unknown SSL error: %d') % self.errnum)
self.ssl_cert = ''
self.ssl_fingerprint_sha1 = ''

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@ -107,6 +107,42 @@ class JIDConstant(IntEnum):
ROOM_TYPE = 1
SSLError = {
2: _("Unable to get issuer certificate"),
3: _("Unable to get certificate CRL"),
4: _("Unable to decrypt certificate's signature"),
5: _("Unable to decrypt CRL's signature"),
6: _("Unable to decode issuer public key"),
7: _("Certificate signature failure"),
8: _("CRL signature failure"),
9: _("Certificate is not yet valid"),
10: _("Certificate has expired"),
11: _("CRL is not yet valid"),
12: _("CRL has expired"),
13: _("Format error in certificate's notBefore field"),
14: _("Format error in certificate's notAfter field"),
15: _("Format error in CRL's lastUpdate field"),
16: _("Format error in CRL's nextUpdate field"),
17: _("Out of memory"),
18: _("Self signed certificate"),
19: _("Self signed certificate in certificate chain"),
20: _("Unable to get local issuer certificate"),
21: _("Unable to verify the first certificate"),
22: _("Certificate chain too long"),
23: _("Certificate revoked"),
24: _("Invalid CA certificate"),
25: _("Path length constraint exceeded"),
26: _("Unsupported certificate purpose"),
27: _("Certificate not trusted"),
28: _("Certificate rejected"),
29: _("Subject issuer mismatch"),
30: _("Authority and subject key identifier mismatch"),
31: _("Authority and issuer serial number mismatch"),
32: _("Key usage does not include certificate signing"),
50: _("Application verification failure"),
}
THANKS = u"""\
Alexander Futász
Alexander V. Butenko

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@ -98,7 +98,7 @@ from gajim.common.connection import Connection
from gajim.common.file_props import FilesProp
from gajim.common import pep
from gajim import emoticons
from gajim.common.const import AvatarSize
from gajim.common.const import AvatarSize, SSLError
from gajim import roster_window
from gajim import profile_window
@ -1343,7 +1343,6 @@ class Interface:
obj.exchange_items_list, obj.fjid)
def handle_event_ssl_error(self, obj):
# ('SSL_ERROR', account, (text, errnum, cert, sha1_fingerprint, sha256_fingerprint))
account = obj.conn.name
server = app.config.get_per('accounts', account, 'hostname')
@ -1379,22 +1378,32 @@ class Interface:
app.nec.push_incoming_event(OurShowEvent(None, conn=obj.conn,
show='offline'))
text = _('The authenticity of the %s '
'certificate could be invalid') % server
default_text = _('\nUnknown SSL error: %d') % obj.error_num
ssl_error_text = SSLError.get(obj.error_num, default_text)
text += _('\nSSL Error: <b>%s</b>') % ssl_error_text
fingerprint_sha1 = obj.cert.digest('sha1').decode('utf-8')
fingerprint_sha256 = obj.cert.digest('sha256').decode('utf-8')
pritext = _('Error verifying SSL certificate')
sectext = _('There was an error verifying the SSL certificate of your '
'XMPP server: %(error)s\nDo you still want to connect to this '
'server?') % {'error': obj.error_text}
'server?') % {'error': text}
if obj.error_num in (18, 27):
checktext1 = _('Add this certificate to the list of trusted '
'certificates.\nSHA-1 fingerprint of the certificate:\n%(sha1)s'
'\nSHA-256 fingerprint of the certificate:\n%(sha256)s') % \
{'sha1': obj.fingerprint_sha1, 'sha256': obj.fingerprint_sha256}
{'sha1': fingerprint_sha1, 'sha256': fingerprint_sha256}
else:
checktext1 = ''
checktext2 = _('Ignore this error for this certificate.')
if 'ssl_error' in self.instances[account]['online_dialog']:
self.instances[account]['online_dialog']['ssl_error'].destroy()
self.instances[account]['online_dialog']['ssl_error'] = \
dialogs.SSLErrorDialog(obj.conn.name, obj.certificate, pritext,
dialogs.SSLErrorDialog(obj.conn.name, obj.cert, pritext,
sectext, checktext1, checktext2, on_response_ok=on_ok,
on_response_cancel=on_cancel)
self.instances[account]['online_dialog']['ssl_error'].set_title(