view hgext/factotum.py @ 33436:9bb4decd43b0

repovfs: add a ward to check if locks are properly taken

When the appropriate developer warnings are enabled, We wrap 'repo.vfs.audit' to
check for locks when accessing file in '.hg' for writing. Another changeset will
add a 'ward' for the store vfs (svfs).

This check system has caught a handful of locking issues that have been fixed
in previous series (mostly in 4.0). I expect another batch to be caught in third
party extensions.

We introduce two real exceptions from extensions 'blackbox.log' (because a lot of
read-only operations add entry to it), and 'last-email.txt' (because 'hg email'
is currently a read only operation and there is value to keep it this way).

In addition we are currently allowing bisect to operate outside of the lock
because the current code is a bit hard to get properly locked for now. Multiple
clean up have been made but there is still a couple of them to do and the freeze
is coming.

# factotum.py - Plan 9 factotum integration for Mercurial
#
# Copyright (C) 2012 Steven Stallion <[e-mail]>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2 of the License, or (at your
# option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
# Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program; if not, write to the Free Software Foundation, Inc.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

'''http authentication with factotum

This extension allows the factotum(4) facility on Plan 9 from Bell Labs
platforms to provide authentication information for HTTP access. Configuration
entries specified in the auth section as well as authentication information
provided in the repository URL are fully supported. If no prefix is specified,
a value of "*" will be assumed.

By default, keys are specified as::

  proto=pass service=hg prefix=<prefix> user=<username> !password=<password>

If the factotum extension is unable to read the required key, one will be
requested interactively.

A configuration section is available to customize runtime behavior. By
default, these entries are::

  [factotum]
  executable = /bin/auth/factotum
  mountpoint = /mnt/factotum
  service = hg

The executable entry defines the full path to the factotum binary. The
mountpoint entry defines the path to the factotum file service. Lastly, the
service entry controls the service name used when reading keys.

'''

from __future__ import absolute_import

import os
from mercurial.i18n import _
from mercurial import (
    error,
    httpconnection,
    registrar,
    url,
    util,
)

urlreq = util.urlreq
passwordmgr = url.passwordmgr

ERRMAX = 128

_executable = _mountpoint = _service = None

configtable = {}
configitem = registrar.configitem(configtable)

configitem('factotum', 'executable',
    default='/bin/auth/factotum',
)
configitem('factotum', 'mountpoint',
    default='/mnt/factotum',
)
configitem('factotum', 'service',
    default='hg',
)

def auth_getkey(self, params):
    if not self.ui.interactive():
        raise error.Abort(_('factotum not interactive'))
    if 'user=' not in params:
        params = '%s user?' % params
    params = '%s !password?' % params
    os.system("%s -g '%s'" % (_executable, params))

def auth_getuserpasswd(self, getkey, params):
    params = 'proto=pass %s' % params
    while True:
        fd = os.open('%s/rpc' % _mountpoint, os.O_RDWR)
        try:
            os.write(fd, 'start %s' % params)
            l = os.read(fd, ERRMAX).split()
            if l[0] == 'ok':
                os.write(fd, 'read')
                status, user, passwd = os.read(fd, ERRMAX).split(None, 2)
                if status == 'ok':
                    if passwd.startswith("'"):
                        if passwd.endswith("'"):
                            passwd = passwd[1:-1].replace("''", "'")
                        else:
                            raise error.Abort(_('malformed password string'))
                    return (user, passwd)
        except (OSError, IOError):
            raise error.Abort(_('factotum not responding'))
        finally:
            os.close(fd)
        getkey(self, params)

def monkeypatch_method(cls):
    def decorator(func):
        setattr(cls, func.__name__, func)
        return func
    return decorator

@monkeypatch_method(passwordmgr)
def find_user_password(self, realm, authuri):
    user, passwd = self.passwddb.find_user_password(realm, authuri)
    if user and passwd:
        self._writedebug(user, passwd)
        return (user, passwd)

    prefix = ''
    res = httpconnection.readauthforuri(self.ui, authuri, user)
    if res:
        _, auth = res
        prefix = auth.get('prefix')
        user, passwd = auth.get('username'), auth.get('password')
    if not user or not passwd:
        if not prefix:
            prefix = realm.split(' ')[0].lower()
        params = 'service=%s prefix=%s' % (_service, prefix)
        if user:
            params = '%s user=%s' % (params, user)
        user, passwd = auth_getuserpasswd(self, auth_getkey, params)

    self.add_password(realm, authuri, user, passwd)
    self._writedebug(user, passwd)
    return (user, passwd)

def uisetup(ui):
    global _executable
    _executable = ui.config('factotum', 'executable')
    global _mountpoint
    _mountpoint = ui.config('factotum', 'mountpoint')
    global _service
    _service = ui.config('factotum', 'service')