|
|
# sslutil.py - SSL handling for mercurial
|
|
|
#
|
|
|
# Copyright 2005, 2006, 2007, 2008 Matt Mackall <mpm@selenic.com>
|
|
|
# Copyright 2006, 2007 Alexis S. L. Carvalho <alexis@cecm.usp.br>
|
|
|
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
|
|
|
#
|
|
|
# This software may be used and distributed according to the terms of the
|
|
|
# GNU General Public License version 2 or any later version.
|
|
|
|
|
|
from __future__ import absolute_import
|
|
|
|
|
|
import os
|
|
|
import ssl
|
|
|
import sys
|
|
|
|
|
|
from .i18n import _
|
|
|
from . import (
|
|
|
error,
|
|
|
util,
|
|
|
)
|
|
|
|
|
|
# Python 2.7.9+ overhauled the built-in SSL/TLS features of Python. It added
|
|
|
# support for TLS 1.1, TLS 1.2, SNI, system CA stores, etc. These features are
|
|
|
# all exposed via the "ssl" module.
|
|
|
#
|
|
|
# Depending on the version of Python being used, SSL/TLS support is either
|
|
|
# modern/secure or legacy/insecure. Many operations in this module have
|
|
|
# separate code paths depending on support in Python.
|
|
|
|
|
|
hassni = getattr(ssl, 'HAS_SNI', False)
|
|
|
|
|
|
try:
|
|
|
OP_NO_SSLv2 = ssl.OP_NO_SSLv2
|
|
|
OP_NO_SSLv3 = ssl.OP_NO_SSLv3
|
|
|
except AttributeError:
|
|
|
OP_NO_SSLv2 = 0x1000000
|
|
|
OP_NO_SSLv3 = 0x2000000
|
|
|
|
|
|
try:
|
|
|
# ssl.SSLContext was added in 2.7.9 and presence indicates modern
|
|
|
# SSL/TLS features are available.
|
|
|
SSLContext = ssl.SSLContext
|
|
|
modernssl = True
|
|
|
_canloaddefaultcerts = util.safehasattr(SSLContext, 'load_default_certs')
|
|
|
except AttributeError:
|
|
|
modernssl = False
|
|
|
_canloaddefaultcerts = False
|
|
|
|
|
|
# We implement SSLContext using the interface from the standard library.
|
|
|
class SSLContext(object):
|
|
|
# ssl.wrap_socket gained the "ciphers" named argument in 2.7.
|
|
|
_supportsciphers = sys.version_info >= (2, 7)
|
|
|
|
|
|
def __init__(self, protocol):
|
|
|
# From the public interface of SSLContext
|
|
|
self.protocol = protocol
|
|
|
self.check_hostname = False
|
|
|
self.options = 0
|
|
|
self.verify_mode = ssl.CERT_NONE
|
|
|
|
|
|
# Used by our implementation.
|
|
|
self._certfile = None
|
|
|
self._keyfile = None
|
|
|
self._certpassword = None
|
|
|
self._cacerts = None
|
|
|
self._ciphers = None
|
|
|
|
|
|
def load_cert_chain(self, certfile, keyfile=None, password=None):
|
|
|
self._certfile = certfile
|
|
|
self._keyfile = keyfile
|
|
|
self._certpassword = password
|
|
|
|
|
|
def load_default_certs(self, purpose=None):
|
|
|
pass
|
|
|
|
|
|
def load_verify_locations(self, cafile=None, capath=None, cadata=None):
|
|
|
if capath:
|
|
|
raise error.Abort('capath not supported')
|
|
|
if cadata:
|
|
|
raise error.Abort('cadata not supported')
|
|
|
|
|
|
self._cacerts = cafile
|
|
|
|
|
|
def set_ciphers(self, ciphers):
|
|
|
if not self._supportsciphers:
|
|
|
raise error.Abort('setting ciphers not supported')
|
|
|
|
|
|
self._ciphers = ciphers
|
|
|
|
|
|
def wrap_socket(self, socket, server_hostname=None, server_side=False):
|
|
|
# server_hostname is unique to SSLContext.wrap_socket and is used
|
|
|
# for SNI in that context. So there's nothing for us to do with it
|
|
|
# in this legacy code since we don't support SNI.
|
|
|
|
|
|
args = {
|
|
|
'keyfile': self._keyfile,
|
|
|
'certfile': self._certfile,
|
|
|
'server_side': server_side,
|
|
|
'cert_reqs': self.verify_mode,
|
|
|
'ssl_version': self.protocol,
|
|
|
'ca_certs': self._cacerts,
|
|
|
}
|
|
|
|
|
|
if self._supportsciphers:
|
|
|
args['ciphers'] = self._ciphers
|
|
|
|
|
|
return ssl.wrap_socket(socket, **args)
|
|
|
|
|
|
def wrapsocket(sock, keyfile, certfile, ui, cert_reqs=ssl.CERT_NONE,
|
|
|
ca_certs=None, serverhostname=None):
|
|
|
"""Add SSL/TLS to a socket.
|
|
|
|
|
|
This is a glorified wrapper for ``ssl.wrap_socket()``. It makes sane
|
|
|
choices based on what security options are available.
|
|
|
|
|
|
In addition to the arguments supported by ``ssl.wrap_socket``, we allow
|
|
|
the following additional arguments:
|
|
|
|
|
|
* serverhostname - The expected hostname of the remote server. If the
|
|
|
server (and client) support SNI, this tells the server which certificate
|
|
|
to use.
|
|
|
"""
|
|
|
# Despite its name, PROTOCOL_SSLv23 selects the highest protocol
|
|
|
# that both ends support, including TLS protocols. On legacy stacks,
|
|
|
# the highest it likely goes in TLS 1.0. On modern stacks, it can
|
|
|
# support TLS 1.2.
|
|
|
#
|
|
|
# The PROTOCOL_TLSv* constants select a specific TLS version
|
|
|
# only (as opposed to multiple versions). So the method for
|
|
|
# supporting multiple TLS versions is to use PROTOCOL_SSLv23 and
|
|
|
# disable protocols via SSLContext.options and OP_NO_* constants.
|
|
|
# However, SSLContext.options doesn't work unless we have the
|
|
|
# full/real SSLContext available to us.
|
|
|
#
|
|
|
# SSLv2 and SSLv3 are broken. We ban them outright.
|
|
|
if modernssl:
|
|
|
protocol = ssl.PROTOCOL_SSLv23
|
|
|
else:
|
|
|
protocol = ssl.PROTOCOL_TLSv1
|
|
|
|
|
|
# TODO use ssl.create_default_context() on modernssl.
|
|
|
sslcontext = SSLContext(protocol)
|
|
|
|
|
|
# This is a no-op on old Python.
|
|
|
sslcontext.options |= OP_NO_SSLv2 | OP_NO_SSLv3
|
|
|
|
|
|
# This still works on our fake SSLContext.
|
|
|
sslcontext.verify_mode = cert_reqs
|
|
|
|
|
|
if certfile is not None:
|
|
|
def password():
|
|
|
f = keyfile or certfile
|
|
|
return ui.getpass(_('passphrase for %s: ') % f, '')
|
|
|
sslcontext.load_cert_chain(certfile, keyfile, password)
|
|
|
|
|
|
if ca_certs is not None:
|
|
|
sslcontext.load_verify_locations(cafile=ca_certs)
|
|
|
caloaded = True
|
|
|
else:
|
|
|
# This is a no-op on old Python.
|
|
|
sslcontext.load_default_certs()
|
|
|
caloaded = _canloaddefaultcerts
|
|
|
|
|
|
sslsocket = sslcontext.wrap_socket(sock, server_hostname=serverhostname)
|
|
|
# check if wrap_socket failed silently because socket had been
|
|
|
# closed
|
|
|
# - see http://bugs.python.org/issue13721
|
|
|
if not sslsocket.cipher():
|
|
|
raise error.Abort(_('ssl connection failed'))
|
|
|
|
|
|
sslsocket._hgcaloaded = caloaded
|
|
|
|
|
|
return sslsocket
|
|
|
|
|
|
def _verifycert(cert, hostname):
|
|
|
'''Verify that cert (in socket.getpeercert() format) matches hostname.
|
|
|
CRLs is not handled.
|
|
|
|
|
|
Returns error message if any problems are found and None on success.
|
|
|
'''
|
|
|
if not cert:
|
|
|
return _('no certificate received')
|
|
|
dnsname = hostname.lower()
|
|
|
def matchdnsname(certname):
|
|
|
return (certname == dnsname or
|
|
|
'.' in dnsname and certname == '*.' + dnsname.split('.', 1)[1])
|
|
|
|
|
|
san = cert.get('subjectAltName', [])
|
|
|
if san:
|
|
|
certnames = [value.lower() for key, value in san if key == 'DNS']
|
|
|
for name in certnames:
|
|
|
if matchdnsname(name):
|
|
|
return None
|
|
|
if certnames:
|
|
|
return _('certificate is for %s') % ', '.join(certnames)
|
|
|
|
|
|
# subject is only checked when subjectAltName is empty
|
|
|
for s in cert.get('subject', []):
|
|
|
key, value = s[0]
|
|
|
if key == 'commonName':
|
|
|
try:
|
|
|
# 'subject' entries are unicode
|
|
|
certname = value.lower().encode('ascii')
|
|
|
except UnicodeEncodeError:
|
|
|
return _('IDN in certificate not supported')
|
|
|
if matchdnsname(certname):
|
|
|
return None
|
|
|
return _('certificate is for %s') % certname
|
|
|
return _('no commonName or subjectAltName found in certificate')
|
|
|
|
|
|
|
|
|
# CERT_REQUIRED means fetch the cert from the server all the time AND
|
|
|
# validate it against the CA store provided in web.cacerts.
|
|
|
|
|
|
def _plainapplepython():
|
|
|
"""return true if this seems to be a pure Apple Python that
|
|
|
* is unfrozen and presumably has the whole mercurial module in the file
|
|
|
system
|
|
|
* presumably is an Apple Python that uses Apple OpenSSL which has patches
|
|
|
for using system certificate store CAs in addition to the provided
|
|
|
cacerts file
|
|
|
"""
|
|
|
if sys.platform != 'darwin' or util.mainfrozen() or not sys.executable:
|
|
|
return False
|
|
|
exe = os.path.realpath(sys.executable).lower()
|
|
|
return (exe.startswith('/usr/bin/python') or
|
|
|
exe.startswith('/system/library/frameworks/python.framework/'))
|
|
|
|
|
|
def _defaultcacerts():
|
|
|
"""return path to default CA certificates or None."""
|
|
|
if _plainapplepython():
|
|
|
dummycert = os.path.join(os.path.dirname(__file__), 'dummycert.pem')
|
|
|
if os.path.exists(dummycert):
|
|
|
return dummycert
|
|
|
|
|
|
return None
|
|
|
|
|
|
def sslkwargs(ui, host):
|
|
|
"""Determine arguments to pass to wrapsocket().
|
|
|
|
|
|
``host`` is the hostname being connected to.
|
|
|
"""
|
|
|
kws = {'ui': ui}
|
|
|
|
|
|
# If a host key fingerprint is on file, it is the only thing that matters
|
|
|
# and CA certs don't come into play.
|
|
|
hostfingerprint = ui.config('hostfingerprints', host)
|
|
|
if hostfingerprint:
|
|
|
return kws
|
|
|
|
|
|
# The code below sets up CA verification arguments. If --insecure is
|
|
|
# used, we don't take CAs into consideration, so return early.
|
|
|
if ui.insecureconnections:
|
|
|
return kws
|
|
|
|
|
|
cacerts = ui.config('web', 'cacerts')
|
|
|
|
|
|
# If a value is set in the config, validate against a path and load
|
|
|
# and require those certs.
|
|
|
if cacerts:
|
|
|
cacerts = util.expandpath(cacerts)
|
|
|
if not os.path.exists(cacerts):
|
|
|
raise error.Abort(_('could not find web.cacerts: %s') % cacerts)
|
|
|
|
|
|
kws.update({'ca_certs': cacerts,
|
|
|
'cert_reqs': ssl.CERT_REQUIRED})
|
|
|
return kws
|
|
|
|
|
|
# No CAs in config. See if we can load defaults.
|
|
|
cacerts = _defaultcacerts()
|
|
|
|
|
|
# We found an alternate CA bundle to use. Load it.
|
|
|
if cacerts:
|
|
|
ui.debug('using %s to enable OS X system CA\n' % cacerts)
|
|
|
ui.setconfig('web', 'cacerts', cacerts, 'defaultcacerts')
|
|
|
kws.update({'ca_certs': cacerts,
|
|
|
'cert_reqs': ssl.CERT_REQUIRED})
|
|
|
return kws
|
|
|
|
|
|
# FUTURE this can disappear once wrapsocket() is secure by default.
|
|
|
if _canloaddefaultcerts:
|
|
|
kws['cert_reqs'] = ssl.CERT_REQUIRED
|
|
|
return kws
|
|
|
|
|
|
return kws
|
|
|
|
|
|
class validator(object):
|
|
|
def __init__(self, ui, host):
|
|
|
self.ui = ui
|
|
|
self.host = host
|
|
|
|
|
|
def __call__(self, sock, strict=False):
|
|
|
host = self.host
|
|
|
|
|
|
if not sock.cipher(): # work around http://bugs.python.org/issue13721
|
|
|
raise error.Abort(_('%s ssl connection error') % host)
|
|
|
try:
|
|
|
peercert = sock.getpeercert(True)
|
|
|
peercert2 = sock.getpeercert()
|
|
|
except AttributeError:
|
|
|
raise error.Abort(_('%s ssl connection error') % host)
|
|
|
|
|
|
if not peercert:
|
|
|
raise error.Abort(_('%s certificate error: '
|
|
|
'no certificate received') % host)
|
|
|
|
|
|
# If a certificate fingerprint is pinned, use it and only it to
|
|
|
# validate the remote cert.
|
|
|
hostfingerprints = self.ui.configlist('hostfingerprints', host)
|
|
|
peerfingerprint = util.sha1(peercert).hexdigest()
|
|
|
nicefingerprint = ":".join([peerfingerprint[x:x + 2]
|
|
|
for x in xrange(0, len(peerfingerprint), 2)])
|
|
|
if hostfingerprints:
|
|
|
fingerprintmatch = False
|
|
|
for hostfingerprint in hostfingerprints:
|
|
|
if peerfingerprint.lower() == \
|
|
|
hostfingerprint.replace(':', '').lower():
|
|
|
fingerprintmatch = True
|
|
|
break
|
|
|
if not fingerprintmatch:
|
|
|
raise error.Abort(_('certificate for %s has unexpected '
|
|
|
'fingerprint %s') % (host, nicefingerprint),
|
|
|
hint=_('check hostfingerprint configuration'))
|
|
|
self.ui.debug('%s certificate matched fingerprint %s\n' %
|
|
|
(host, nicefingerprint))
|
|
|
return
|
|
|
|
|
|
# If insecure connections were explicitly requested via --insecure,
|
|
|
# print a warning and do no verification.
|
|
|
#
|
|
|
# It may seem odd that this is checked *after* host fingerprint pinning.
|
|
|
# This is for backwards compatibility (for now). The message is also
|
|
|
# the same as below for BC.
|
|
|
if self.ui.insecureconnections:
|
|
|
self.ui.warn(_('warning: %s certificate with fingerprint %s not '
|
|
|
'verified (check hostfingerprints or web.cacerts '
|
|
|
'config setting)\n') %
|
|
|
(host, nicefingerprint))
|
|
|
return
|
|
|
|
|
|
if not sock._hgcaloaded:
|
|
|
if strict:
|
|
|
raise error.Abort(_('%s certificate with fingerprint %s not '
|
|
|
'verified') % (host, nicefingerprint),
|
|
|
hint=_('check hostfingerprints or '
|
|
|
'web.cacerts config setting'))
|
|
|
else:
|
|
|
self.ui.warn(_('warning: %s certificate with fingerprint %s '
|
|
|
'not verified (check hostfingerprints or '
|
|
|
'web.cacerts config setting)\n') %
|
|
|
(host, nicefingerprint))
|
|
|
|
|
|
return
|
|
|
|
|
|
msg = _verifycert(peercert2, host)
|
|
|
if msg:
|
|
|
raise error.Abort(_('%s certificate error: %s') % (host, msg),
|
|
|
hint=_('configure hostfingerprint %s or use '
|
|
|
'--insecure to connect insecurely') %
|
|
|
nicefingerprint)
|
|
|
|
