view mercurial/sslutil.py @ 18796:fa6d5c62f3bd

pathcomplete: complete directories more conservatively

Suppose we want to perform a single-level completion (i.e. without
--full) of "fi" in a repo containing "fee", "fie/dead", "fie/live",
and "foe".

If we give back "fie/" as the only answer, the shell will consider
the completion to be unambiguous, and will append a space after the
completion.  We can't complete "fie/live" or "fie/dead" without
first backspacing over that space.

We used to thus create two fake names, "fie/a" and "fie/b", to force
the shell to consider the completion to be ambiguous. It would then
stop at "fie/" without appending a space, allowing us to hit tab
again to complete "fie/live" or "fie/dead".

The change here arises from realising that we only need to force
the shell to consider a completion as ambiguous if we have exactly
one directory and zero files as possible completions.

This prevents spurious names from showing up as possible completions
when they don't need to be invented in the first place.

# sslutil.py - SSL handling for mercurial
#
# Copyright 2005, 2006, 2007, 2008 Matt Mackall <[e-mail]>
# Copyright 2006, 2007 Alexis S. L. Carvalho <[e-mail]>
# Copyright 2006 Vadim Gelfer <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
import os

from mercurial import util
from mercurial.i18n import _
try:
    # avoid using deprecated/broken FakeSocket in python 2.6
    import ssl
    CERT_REQUIRED = ssl.CERT_REQUIRED
    def ssl_wrap_socket(sock, keyfile, certfile,
                cert_reqs=ssl.CERT_NONE, ca_certs=None):
        sslsocket = ssl.wrap_socket(sock, keyfile, certfile,
                cert_reqs=cert_reqs, ca_certs=ca_certs)
        # check if wrap_socket failed silently because socket had been closed
        # - see http://bugs.python.org/issue13721
        if not sslsocket.cipher():
            raise util.Abort(_('ssl connection failed'))
        return sslsocket
except ImportError:
    CERT_REQUIRED = 2

    import socket, httplib

    def ssl_wrap_socket(sock, key_file, cert_file,
                        cert_reqs=CERT_REQUIRED, ca_certs=None):
        if not util.safehasattr(socket, 'ssl'):
            raise util.Abort(_('Python SSL support not found'))
        if ca_certs:
            raise util.Abort(_(
                'certificate checking requires Python 2.6'))

        ssl = socket.ssl(sock, key_file, cert_file)
        return httplib.FakeSocket(sock, ssl)

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.
#
# We COMPLETELY ignore CERT_REQUIRED on Python <= 2.5, as it's totally
# busted on those versions.

def sslkwargs(ui, host):
    cacerts = ui.config('web', 'cacerts')
    hostfingerprint = ui.config('hostfingerprints', host)
    if cacerts and not hostfingerprint:
        cacerts = util.expandpath(cacerts)
        if not os.path.exists(cacerts):
            raise util.Abort(_('could not find web.cacerts: %s') % cacerts)
        return {'ca_certs': cacerts,
                'cert_reqs': CERT_REQUIRED,
                }
    return {}

class validator(object):
    def __init__(self, ui, host):
        self.ui = ui
        self.host = host

    def __call__(self, sock):
        host = self.host
        cacerts = self.ui.config('web', 'cacerts')
        hostfingerprint = self.ui.config('hostfingerprints', host)
        if not getattr(sock, 'getpeercert', False): # python 2.5 ?
            if hostfingerprint:
                raise util.Abort(_("host fingerprint for %s can't be "
                                   "verified (Python too old)") % host)
            if self.ui.configbool('ui', 'reportoldssl', True):
                self.ui.warn(_("warning: certificate for %s can't be verified "
                               "(Python too old)\n") % host)
            return
        if not sock.cipher(): # work around http://bugs.python.org/issue13721
            raise util.Abort(_('%s ssl connection error') % host)
        peercert = sock.getpeercert(True)
        if not peercert:
            raise util.Abort(_('%s certificate error: '
                               'no certificate received') % host)
        peerfingerprint = util.sha1(peercert).hexdigest()
        nicefingerprint = ":".join([peerfingerprint[x:x + 2]
            for x in xrange(0, len(peerfingerprint), 2)])
        if hostfingerprint:
            if peerfingerprint.lower() != \
                    hostfingerprint.replace(':', '').lower():
                raise util.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))
        elif cacerts:
            msg = _verifycert(sock.getpeercert(), host)
            if msg:
                raise util.Abort(_('%s certificate error: %s') % (host, msg),
                                 hint=_('configure hostfingerprint %s or use '
                                        '--insecure to connect insecurely') %
                                      nicefingerprint)
            self.ui.debug('%s certificate successfully verified\n' % host)
        else:
            self.ui.warn(_('warning: %s certificate with fingerprint %s not '
                           'verified (check hostfingerprints or web.cacerts '
                           'config setting)\n') %
                         (host, nicefingerprint))