# -*- coding: utf-8 -*-

"""

    rhodecode.lib.auth

    ~~~~~~~~~~~~~~~~~~

    authentication and permission libraries

    :created_on: Apr 4, 2010

    :author: marcink

    :copyright: (C) 2010-2012 Marcin Kuzminski <marcin@python-works.com>

    :license: GPLv3, see COPYING for more details.

"""

# 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 3 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, see <http://www.gnu.org/licenses/>.

import random

import logging

import traceback

import hashlib

from tempfile import _RandomNameSequence

from decorator import decorator

from pylons import config, url, request

from pylons.controllers.util import abort, redirect

from pylons.i18n.translation import _

from rhodecode import __platform__, PLATFORM_WIN, PLATFORM_OTHERS

from rhodecode.model.meta import Session

if __platform__ in PLATFORM_WIN:

    from hashlib import sha256

if __platform__ in PLATFORM_OTHERS:

    import bcrypt

from rhodecode.lib import str2bool, safe_unicode

from rhodecode.lib.exceptions import LdapPasswordError, LdapUsernameError

from rhodecode.lib.utils import get_repo_slug, get_repos_group_slug

from rhodecode.lib.auth_ldap import AuthLdap

from rhodecode.model import meta

from rhodecode.model.user import UserModel

from rhodecode.model.db import Permission, RhodeCodeSetting, User

log = logging.getLogger(__name__)

class PasswordGenerator(object):

    """

    This is a simple class for generating password from different sets of

    characters

    usage::

        passwd_gen = PasswordGenerator()

        #print 8-letter password containing only big and small letters

            of alphabet

        print passwd_gen.gen_password(8, passwd_gen.ALPHABETS_BIG_SMALL)

    """

    ALPHABETS_NUM = r'''1234567890'''

    ALPHABETS_SMALL = r'''qwertyuiopasdfghjklzxcvbnm'''

    ALPHABETS_BIG = r'''QWERTYUIOPASDFGHJKLZXCVBNM'''

    ALPHABETS_SPECIAL = r'''`-=[]\;',./~!@#$%^&*()_+{}|:"<>?'''

    ALPHABETS_FULL = ALPHABETS_BIG + ALPHABETS_SMALL \

        + ALPHABETS_NUM + ALPHABETS_SPECIAL

    ALPHABETS_ALPHANUM = ALPHABETS_BIG + ALPHABETS_SMALL + ALPHABETS_NUM

    ALPHABETS_BIG_SMALL = ALPHABETS_BIG + ALPHABETS_SMALL

    ALPHABETS_ALPHANUM_BIG = ALPHABETS_BIG + ALPHABETS_NUM

    ALPHABETS_ALPHANUM_SMALL = ALPHABETS_SMALL + ALPHABETS_NUM

    def __init__(self, passwd=''):

        self.passwd = passwd

    def gen_password(self, length, type_=None):

        if type_ is None:

            type_ = self.ALPHABETS_FULL

        self.passwd = ''.join([random.choice(type_) for _ in xrange(length)])

        return self.passwd

class RhodeCodeCrypto(object):

    @classmethod

    def hash_string(cls, str_):

        """

        Cryptographic function used for password hashing based on pybcrypt

        or pycrypto in windows

        :param password: password to hash

        """

        if __platform__ in PLATFORM_WIN:

            return sha256(str_).hexdigest()

        elif __platform__ in PLATFORM_OTHERS:

            return bcrypt.hashpw(str_, bcrypt.gensalt(10))

        else:

            raise Exception('Unknown or unsupported platform %s' \

                            % __platform__)

    @classmethod

    def hash_check(cls, password, hashed):

        """

        Checks matching password with it's hashed value, runs different

        implementation based on platform it runs on

        :param password: password

        :param hashed: password in hashed form

        """

        if __platform__ in PLATFORM_WIN:

            return sha256(password).hexdigest() == hashed

        elif __platform__ in PLATFORM_OTHERS:

            return bcrypt.hashpw(password, hashed) == hashed

        else:

            raise Exception('Unknown or unsupported platform %s' \

                            % __platform__)

def get_crypt_password(password):

    return RhodeCodeCrypto.hash_string(password)

def check_password(password, hashed):

    return RhodeCodeCrypto.hash_check(password, hashed)

def generate_api_key(str_, salt=None):

    """

    Generates API KEY from given string

    :param str_:

    :param salt:

    """

    if salt is None:

        salt = _RandomNameSequence().next()

    return hashlib.sha1(str_ + salt).hexdigest()

def authfunc(environ, username, password):

    """

    Dummy authentication wrapper function used in Mercurial and Git for

    access control.

    :param environ: needed only for using in Basic auth

    """

    return authenticate(username, password)

def authenticate(username, password):

    """

    Authentication function used for access control,

    firstly checks for db authentication then if ldap is enabled for ldap

    authentication, also creates ldap user if not in database

    :param username: username

    :param password: password

    """

    user_model = UserModel()

    user = User.get_by_username(username)

    log.debug('Authenticating user using RhodeCode account')

    if user is not None and not user.ldap_dn:

        if user.active:

            if user.username == 'default' and user.active:

                log.info('user %s authenticated correctly as anonymous user' %

                         username)

                return True

            elif user.username == username and check_password(password,

                                                              user.password):

                log.info('user %s authenticated correctly' % username)

                return True

        else:

            log.warning('user %s tried auth but is disabled' % username)

    else:

        log.debug('Regular authentication failed')

        user_obj = User.get_by_username(username, case_insensitive=True)

        if user_obj is not None and not user_obj.ldap_dn:

            log.debug('this user already exists as non ldap')

            return False

        ldap_settings = RhodeCodeSetting.get_ldap_settings()

        #======================================================================

        # FALLBACK TO LDAP AUTH IF ENABLE

        #======================================================================

        if str2bool(ldap_settings.get('ldap_active')):

            log.debug("Authenticating user using ldap")

            kwargs = {

                  'server': ldap_settings.get('ldap_host', ''),

                  'base_dn': ldap_settings.get('ldap_base_dn', ''),

                  'port': ldap_settings.get('ldap_port'),

                  'bind_dn': ldap_settings.get('ldap_dn_user'),

                  'bind_pass': ldap_settings.get('ldap_dn_pass'),

                  'tls_kind': ldap_settings.get('ldap_tls_kind'),

                  'tls_reqcert': ldap_settings.get('ldap_tls_reqcert'),

                  'ldap_filter': ldap_settings.get('ldap_filter'),

                  'search_scope': ldap_settings.get('ldap_search_scope'),

                  'attr_login': ldap_settings.get('ldap_attr_login'),

                  'ldap_version': 3,

                  }

            log.debug('Checking for ldap authentication')

            try:

                aldap = AuthLdap(**kwargs)

                (user_dn, ldap_attrs) = aldap.authenticate_ldap(username,

                                                                password)

                log.debug('Got ldap DN response %s' % user_dn)

                get_ldap_attr = lambda k: ldap_attrs.get(ldap_settings\

                                                           .get(k), [''])[0]

                user_attrs = {

                 'name': safe_unicode(get_ldap_attr('ldap_attr_firstname')),

                 'lastname': safe_unicode(get_ldap_attr('ldap_attr_lastname')),

                 'email': get_ldap_attr('ldap_attr_email'),

                }

                # don't store LDAP password since we don't need it. Override

                # with some random generated password

                _password = PasswordGenerator().gen_password(length=8)

                # create this user on the fly if it doesn't exist in rhodecode

                # database

                if user_model.create_ldap(username, _password, user_dn,

                                          user_attrs):

                    log.info('created new ldap user %s' % username)

                Session.commit()

                return True

            except (LdapUsernameError, LdapPasswordError,):

                pass

            except (Exception,):

                log.error(traceback.format_exc())

                pass

    return False

def login_container_auth(username):

    user = User.get_by_username(username)

    if user is None:

        user_attrs = {

            'name': username,

            'lastname': None,

            'email': None,

        }

        user = UserModel().create_for_container_auth(username, user_attrs)

        if not user:

            return None

        log.info('User %s was created by container authentication' % username)

    if not user.active:

        return None

    user.update_lastlogin()

    Session.commit()

    log.debug('User %s is now logged in by container authentication',

              user.username)

    return user

def get_container_username(environ, config):

    username = None

    if str2bool(config.get('container_auth_enabled', False)):

        from paste.httpheaders import REMOTE_USER

        username = REMOTE_USER(environ)

    if not username and str2bool(config.get('proxypass_auth_enabled', False)):

        username = environ.get('HTTP_X_FORWARDED_USER')

    if username:

        # Removing realm and domain from username

        username = username.partition('@')[0]

        username = username.rpartition('\\')[2]

        log.debug('Received username %s from container' % username)

    return username

class  AuthUser(object):

    """

    A simple object that handles all attributes of user in RhodeCode

    It does lookup based on API key,given user, or user present in session

    Then it fills all required information for such user. It also checks if

    anonymous access is enabled and if so, it returns default user as logged

    in

    """

    def __init__(self, user_id=None, api_key=None, username=None):

        self.user_id = user_id

        self.api_key = None

        self.username = username

        self.name = ''

        self.lastname = ''

        self.email = ''

        self.is_authenticated = False

        self.admin = False

        self.permissions = {}

        self._api_key = api_key

        self.propagate_data()

        self._instance = None

    def propagate_data(self):

        user_model = UserModel()

        self.anonymous_user = User.get_by_username('default', cache=True)

        is_user_loaded = False

        # try go get user by api key

        if self._api_key and self._api_key != self.anonymous_user.api_key:

            log.debug('Auth User lookup by API KEY %s' % self._api_key)

            is_user_loaded = user_model.fill_data(self, api_key=self._api_key)

        # lookup by userid

        elif (self.user_id is not None and

              self.user_id != self.anonymous_user.user_id):

            log.debug('Auth User lookup by USER ID %s' % self.user_id)

            is_user_loaded = user_model.fill_data(self, user_id=self.user_id)

        # lookup by username

        elif self.username and \

            str2bool(config.get('container_auth_enabled', False)):

            log.debug('Auth User lookup by USER NAME %s' % self.username)

            dbuser = login_container_auth(self.username)

            if dbuser is not None:

                for k, v in dbuser.get_dict().items():

                    setattr(self, k, v)

                self.set_authenticated()

                is_user_loaded = True

        if not is_user_loaded:

            # if we cannot authenticate user try anonymous

            if self.anonymous_user.active is True:

                user_model.fill_data(self, user_id=self.anonymous_user.user_id)

                # then we set this user is logged in

                self.is_authenticated = True

            else:

                self.user_id = None

                self.username = None

                self.is_authenticated = False

        if not self.username:

            self.username = 'None'

        log.debug('Auth User is now %s' % self)

        user_model.fill_perms(self)

    @property

    def is_admin(self):

        return self.admin

    def __repr__(self):

        return "<AuthUser('id:%s:%s|%s')>" % (self.user_id, self.username,

                                              self.is_authenticated)

    def set_authenticated(self, authenticated=True):

        if self.user_id != self.anonymous_user.user_id:

            self.is_authenticated = authenticated

    def get_cookie_store(self):

        return {'username': self.username,

                'user_id': self.user_id,

                'is_authenticated': self.is_authenticated}

    @classmethod

    def from_cookie_store(cls, cookie_store):

        user_id = cookie_store.get('user_id')

        username = cookie_store.get('username')

        api_key = cookie_store.get('api_key')

        return AuthUser(user_id, api_key, username)

def set_available_permissions(config):

    """

    This function will propagate pylons globals with all available defined

    permission given in db. We don't want to check each time from db for new

    permissions since adding a new permission also requires application restart

    ie. to decorate new views with the newly created permission

    :param config: current pylons config instance

    """

    log.info('getting information about all available permissions')

    try:

        sa = meta.Session

        all_perms = sa.query(Permission).all()

    except Exception:

        pass

    finally:

        meta.Session.remove()

    config['available_permissions'] = [x.permission_name for x in all_perms]

#==============================================================================

# CHECK DECORATORS

#==============================================================================

class LoginRequired(object):

    """

    Must be logged in to execute this function else

    redirect to login page

    :param api_access: if enabled this checks only for valid auth token

        and grants access based on valid token

    """

    def __init__(self, api_access=False):

        self.api_access = api_access

    def __call__(self, func):

        return decorator(self.__wrapper, func)

    def __wrapper(self, func, *fargs, **fkwargs):

        cls = fargs[0]

        user = cls.rhodecode_user

        api_access_ok = False

        if self.api_access:

            log.debug('Checking API KEY access for %s' % cls)

            if user.api_key == request.GET.get('api_key'):

                api_access_ok = True

            else:

                log.debug("API KEY token not valid")

        loc = "%s:%s" % (cls.__class__.__name__, func.__name__)

        log.debug('Checking if %s is authenticated @ %s' % (user.username, loc))

        if user.is_authenticated or api_access_ok:

            log.info('user %s is authenticated and granted access to %s' % (

                       user.username, loc)

            )

            return func(*fargs, **fkwargs)

        else:

            log.warn('user %s NOT authenticated on func: %s' % (

                user, loc)

            )

            p = url.current()

            log.debug('redirecting to login page with %s' % p)

            return redirect(url('login_home', came_from=p))

class NotAnonymous(object):

    """

    Must be logged in to execute this function else

    redirect to login page"""

    def __call__(self, func):

        return decorator(self.__wrapper, func)

    def __wrapper(self, func, *fargs, **fkwargs):

        cls = fargs[0]

        self.user = cls.rhodecode_user

        log.debug('Checking if user is not anonymous @%s' % cls)

        anonymous = self.user.username == 'default'

        if anonymous:

            p = url.current()

            import rhodecode.lib.helpers as h

            h.flash(_('You need to be a registered user to '

                      'perform this action'),

                    category='warning')

            return redirect(url('login_home', came_from=p))

        else:

            return func(*fargs, **fkwargs)

class PermsDecorator(object):

    """Base class for controller decorators"""

    def __init__(self, *required_perms):

        available_perms = config['available_permissions']

        for perm in required_perms:

            if perm not in available_perms:

                raise Exception("'%s' permission is not defined" % perm)

        self.required_perms = set(required_perms)

        self.user_perms = None

    def __call__(self, func):

        return decorator(self.__wrapper, func)

    def __wrapper(self, func, *fargs, **fkwargs):

        cls = fargs[0]

        self.user = cls.rhodecode_user

        self.user_perms = self.user.permissions

        log.debug('checking %s permissions %s for %s %s',

           self.__class__.__name__, self.required_perms, cls,

               self.user)

        if self.check_permissions():

            log.debug('Permission granted for %s %s' % (cls, self.user))

            return func(*fargs, **fkwargs)

        else:

            log.debug('Permission denied for %s %s' % (cls, self.user))

            anonymous = self.user.username == 'default'

            if anonymous:

                p = url.current()

                import rhodecode.lib.helpers as h

                h.flash(_('You need to be a signed in to '

                          'view this page'),

                        category='warning')

                return redirect(url('login_home', came_from=p))

            else:

                # redirect with forbidden ret code

                return abort(403)

    def check_permissions(self):

        """Dummy function for overriding"""

        raise Exception('You have to write this function in child class')

class HasPermissionAllDecorator(PermsDecorator):

    """

    Checks for access permission for all given predicates. All of them

    have to be meet in order to fulfill the request

    """

    def check_permissions(self):

        if self.required_perms.issubset(self.user_perms.get('global')):

            return True

        return False

class HasPermissionAnyDecorator(PermsDecorator):

    """

    Checks for access permission for any of given predicates. In order to

    fulfill the request any of predicates must be meet

    """

    def check_permissions(self):

        if self.required_perms.intersection(self.user_perms.get('global')):

            return True

        return False

class HasRepoPermissionAllDecorator(PermsDecorator):

    """

    Checks for access permission for all given predicates for specific

    repository. All of them have to be meet in order to fulfill the request

    """

    def check_permissions(self):

        repo_name = get_repo_slug(request)

        try:

            user_perms = set([self.user_perms['repositories'][repo_name]])

        except KeyError:

            return False

        if self.required_perms.issubset(user_perms):

            return True

        return False

class HasRepoPermissionAnyDecorator(PermsDecorator):

    """

    Checks for access permission for any of given predicates for specific

    repository. In order to fulfill the request any of predicates must be meet

    """

    def check_permissions(self):

        repo_name = get_repo_slug(request)

        try:

            user_perms = set([self.user_perms['repositories'][repo_name]])

        except KeyError:

            return False

        if self.required_perms.intersection(user_perms):

            return True

        return False

class HasReposGroupPermissionAllDecorator(PermsDecorator):

    """

    Checks for access permission for all given predicates for specific

    repository. All of them have to be meet in order to fulfill the request

    """

    def check_permissions(self):

        group_name = get_repos_group_slug(request)

        try:

            user_perms = set([self.user_perms['repositories_groups'][group_name]])

        except KeyError:

            return False

        if self.required_perms.issubset(user_perms):

            return True

        return False

class HasReposGroupPermissionAnyDecorator(PermsDecorator):

    """

    Checks for access permission for any of given predicates for specific

    repository. In order to fulfill the request any of predicates must be meet

    """

    def check_permissions(self):

        group_name = get_repos_group_slug(request)

        try:

            user_perms = set([self.user_perms['repositories_groups'][group_name]])

        except KeyError:

            return False

        if self.required_perms.intersection(user_perms):

            return True

        return False

#==============================================================================

# CHECK FUNCTIONS

#==============================================================================

class PermsFunction(object):

    """Base function for other check functions"""

    def __init__(self, *perms):

        available_perms = config['available_permissions']

        for perm in perms:

            if perm not in available_perms:

                raise Exception("'%s' permission in not defined" % perm)

        self.required_perms = set(perms)

        self.user_perms = None

        self.granted_for = ''

        self.repo_name = None

    def __call__(self, check_Location=''):

        user = request.user

        if not user:

            return False

        self.user_perms = user.permissions

        self.granted_for = user

        log.debug('checking %s %s %s', self.__class__.__name__,

                  self.required_perms, user)

        if self.check_permissions():

            log.debug('Permission granted %s @ %s', self.granted_for,

                      check_Location or 'unspecified location')

            return True

        else:

            log.debug('Permission denied for %s @ %s', self.granted_for,

                        check_Location or 'unspecified location')

            return False

    def check_permissions(self):

        """Dummy function for overriding"""

        raise Exception('You have to write this function in child class')

class HasPermissionAll(PermsFunction):

    def check_permissions(self):

        if self.required_perms.issubset(self.user_perms.get('global')):

            return True

        return False

class HasPermissionAny(PermsFunction):

    def check_permissions(self):

        if self.required_perms.intersection(self.user_perms.get('global')):

            return True

        return False

class HasRepoPermissionAll(PermsFunction):

    def __call__(self, repo_name=None, check_Location=''):

        self.repo_name = repo_name

        return super(HasRepoPermissionAll, self).__call__(check_Location)

    def check_permissions(self):

        if not self.repo_name:

            self.repo_name = get_repo_slug(request)

        try:

            self.user_perms = set(

                [self.user_perms['repositories'][self.repo_name]]

            )

        except KeyError:

            return False

        self.granted_for = self.repo_name

        if self.required_perms.issubset(self.user_perms):

            return True

        return False

class HasRepoPermissionAny(PermsFunction):

    def __call__(self, repo_name=None, check_Location=''):

        self.repo_name = repo_name

        return super(HasRepoPermissionAny, self).__call__(check_Location)

    def check_permissions(self):

        if not self.repo_name:

            self.repo_name = get_repo_slug(request)

        try:

            self.user_perms = set(

                [self.user_perms['repositories'][self.repo_name]]

            )

        except KeyError:

            return False

        self.granted_for = self.repo_name

        if self.required_perms.intersection(self.user_perms):

            return True

        return False

class HasReposGroupPermissionAny(PermsFunction):

    def __call__(self, group_name=None, check_Location=''):

        self.group_name = group_name

        return super(HasReposGroupPermissionAny, self).__call__(check_Location)

    def check_permissions(self):

        try:

            self.user_perms = set(

                [self.user_perms['repositories_groups'][self.group_name]]

            )

        except KeyError:

            return False

        self.granted_for = self.repo_name

        if self.required_perms.intersection(self.user_perms):

            return True

        return False

class HasReposGroupPermissionAll(PermsFunction):

    def __call__(self, group_name=None, check_Location=''):

        self.group_name = group_name

        return super(HasReposGroupPermissionAny, self).__call__(check_Location)

    def check_permissions(self):

        try:

            self.user_perms = set(

                [self.user_perms['repositories_groups'][self.group_name]]

            )

        except KeyError:

            return False

        self.granted_for = self.repo_name

        if self.required_perms.issubset(self.user_perms):

            return True

        return False

#==============================================================================

# SPECIAL VERSION TO HANDLE MIDDLEWARE AUTH

#==============================================================================

class HasPermissionAnyMiddleware(object):

    def __init__(self, *perms):

        self.required_perms = set(perms)

    def __call__(self, user, repo_name):

        usr = AuthUser(user.user_id)

        try:

            self.user_perms = set([usr.permissions['repositories'][repo_name]])

        except:

            self.user_perms = set()

        self.granted_for = ''

        self.username = user.username

        self.repo_name = repo_name

        return self.check_permissions()

    def check_permissions(self):

        log.debug('checking mercurial protocol '

                  'permissions %s for user:%s repository:%s', self.user_perms,

                                                self.username, self.repo_name)

        if self.required_perms.intersection(self.user_perms):

            log.debug('permission granted')

            return True

        log.debug('permission denied')

        return False

"""The base Controller API

Provides the BaseController class for subclassing.

"""

import logging

import time

import traceback

from paste.auth.basic import AuthBasicAuthenticator

from pylons import config, tmpl_context as c, request, session, url

from pylons.controllers import WSGIController

from pylons.controllers.util import redirect

from pylons.templating import render_mako as render

from rhodecode import __version__, BACKENDS

from rhodecode.lib import str2bool, safe_unicode

from rhodecode.lib.auth import AuthUser, get_container_username, authfunc,\

from rhodecode.lib.utils import get_repo_slug, invalidate_cache

from rhodecode.model import meta

from rhodecode.model.db import Repository

from rhodecode.model.notification import NotificationModel

from rhodecode.model.scm import ScmModel

log = logging.getLogger(__name__)

class BaseVCSController(object):

    def __init__(self, application, config):

        self.application = application

        self.config = config

        # base path of repo locations

        self.basepath = self.config['base_path']

        #authenticate this mercurial request using authfunc

        self.authenticate = AuthBasicAuthenticator('', authfunc)

        self.ipaddr = '0.0.0.0'

    def _handle_request(self, environ, start_response):

        raise NotImplementedError()

    def _get_by_id(self, repo_name):

        """

        Get's a special pattern _<ID> from clone url and tries to replace it

        with a repository_name for support of _<ID> non changable urls

        :param repo_name:

        """

        try:

            data = repo_name.split('/')

            if len(data) >= 2:

                by_id = data[1].split('_')

                if len(by_id) == 2 and by_id[1].isdigit():

                    _repo_name = Repository.get(by_id[1]).repo_name

                    data[1] = _repo_name

        except:

            log.debug('Failed to extract repo_name from id %s' % (

                      traceback.format_exc()

                      )

            )

        return '/'.join(data)

    def _invalidate_cache(self, repo_name):