repo groups: make it possible to remove own explicit permissions, now when group owners always have admin permissions

Until recently, group owners very given explicit admin permissions on repo
group, and special care was taken to make sure they didn't remove themselves.

Now we always give admin permissions to owners, and don't care about the
explicit permissions. We no longer add them when creating groups or changing
owner. There is no migration step to remove redundant permissions, but we
should allow group admins to remove them. This change will thus remove the
mechanism for preventing removal of own/owner permissions.

repo group: introduce editing of owner

The repo group owner concept was only partially implemented. Owners were shown
in the repo group listing, but couldn't be changed. Users owning repo groups
couldn't be deleted, with no other solution than deleting owned repo groups.

This also fixes the existing broken update_repo_group API, which tried to use
unimplemented functionality.

repo_groups: fix deletion of subgroups

Deletion of a repository group that has a parent group (i.e. is not at the
root of the repository group tree) failed as follows:

Traceback (most recent call last):
[...]
File ".../lib/python3.9/site-packages/tg/configurator/components/dispatch.py", line 114, in _call_controller
return controller(*remainder, **params)
File "<decorator-gen-5>", line 2, in delete

File "/home/tdescham/repo/contrib/kallithea/kallithea-release/kallithea/lib/auth.py", line 572, in __wrapper
return func(*fargs, **fkwargs)
File "/home/tdescham/repo/contrib/kallithea/kallithea-release/kallithea/controllers/admin/repo_groups.py", line 271, in delete
if gr.parent_group:
File ".../lib/python3.9/site-packages/sqlalchemy/orm/attributes.py", line 294, in __get__
return self.impl.get(instance_state(instance), dict_)
File ".../lib/python3.9/site-packages/sqlalchemy/orm/attributes.py", line 730, in get
value = self.callable_(state, passive)
File ".../lib/python3.9/site-packages/sqlalchemy/orm/strategies.py", line 717, in _load_for_state
raise orm_exc.DetachedInstanceError(
sqlalchemy.orm.exc.DetachedInstanceError: Parent instance <RepoGroup at 0x7f1f2664f4c0> is not bound to a Session; lazy load operation of attribute 'parent_group' cannot proceed (Background on this error at: http://sqlalche.me/e/13/bhk3)


In the reference 'gr.parent_group', 'gr' is an SQLAlchemy object referring
to the group being deleted, and 'gr.parent_group' is a lazy reference to its
parent group. The 'lazy' means that the parent group object is not loaded
automatically when 'gr' is assigned, but instead will be loaded on-the-fly
when the parent group is actually accessed. See [1] and [2] for more
information.

The problem was that the lazy 'parent_group' attribute was accessed _after_
deleting the database object it was part of.

Fix this by obtaining a handle to the parent group _before_ deleting the
subgroup.

Reported-by: André Klitzing (via mailing list)


[1] https://docs.sqlalchemy.org/en/13/errors.html#error-bhk3
[2] https://docs.sqlalchemy.org/en/13/orm/loading_relationships.html

controllers: move controllers base class from lib/base to controllers

TG quickstart put it in lib/base.py , but it fits better on the controllers
layer as a base there.

The contributing docs were a bit ahead of time ... but with a typo.

lib: clean up pointless use of h.person on db.User just to get .username

After cleaning up, h.person will never be invoked with a db.User .

repo_groups: fix select of parent group when adding repo group

h.select was passed a list of repo groups where group_id was integer, but
parent_group in the request was a string - thus no match.

Do as in repos controller create_repository (and in error handling): leave it
to htmlfill to patch up the generated HTML using defaults ... but make sure we
always have a default.

repos: extra HTML escaping of repo and repo group names shown in DataTables

These names will already have been "slugged" and can thus not contain anything
that can be used for any attack. But let's be explicitly safe and escape them
anyway.

raw_name without escaping would cause XSS *if* it was possible to create unsafe
repo names.

just_name must be escaped in order to make search work correctly - for example
if searching for '<' ... *if* it was possible for names to contain that.

lib: consistently import helpers the same way

Make it easier to grep for any remaining potential layering-violating use of
helpers.

lib: move webhelpers2 and friends to webutils

Gives less of the unfortunate use of helpers - especially in low level libs.

lib: fix bad references to utils3

A problem introduced in when rebasing 5e46f73f0d1c after renaming the temporary
utils3 name to webutils.

routing: separate url handling from routing - move it to webutils

This is a helper method relying on the thread local tg.request. We didn't have
a good place to put it. Now we do.

This (re)moves unfortunate dependencies to the routing module (which almost is
a controller).

cleanup: minimize use of lambda expressions - we have 'def' for that purpose

Fix some flake8 warnings "E731 do not assign a lambda expression, use a def".

py3: remove safe_unicode in places where it no longer is needed because all strings (except bytes) already *are* unicode strings

(The remaining safe_unicode calls are still needed and can't just be removed,
generally because we in these cases still have to convert from bytes to unicode
strings.)

cleanup: minor correctness fixes

"Trivial" potential problems spotted with pytype.

controllers: use unicode for internal rendering of template snippets

Like 8e2313be042d.

py3: use comprehensions and generators instead of filters - it is more explicit, and sometimes shorter

From 2to3 -f filter.

py3: cleanup map usage and avoid py3 ambiguity

Based on 2to3 -f map ... but replace map with something more explicit (unless
born and raised in a lisp world) (but sometimes slightly more verbose).

auth: refactor to introduce @LoginRequired(allow_default_user=True) and deprecate @NotAnonymous()

It was error prone that @LoginRequired defaulted to allow anonymous users (if
'default' user is enabled). See also 245b4e3abf39.

Refactor code to make it more explicit and safe by default: Deprecate
@NotAnonymous by making it the default of @LoginRequired. That will make it
safe by default.

To preserve same functionality, set allow_default_user=True in all the cases
where @LoginRequired was *not* followed by @NotAnonymous or other permission
checks - that was done with some script hacks:
sed -i 's/@LoginRequired(\(..*\))/@LoginRequired(\1, allow_default_user=True)/g' `hg mani`
sed -i 's/@LoginRequired()/@LoginRequired(allow_default_user=True)/g' `hg mani`
perl -0pi -e 's/\@LoginRequired\(allow_default_user=True\)\n\s*\@NotAnonymous\(\)/\@LoginRequired()/g' `hg mani`
perl -0pi -e 's/\@LoginRequired\(allow_default_user=True\)(\n\s*\@Has(Repo)?Permission)/\@LoginRequired()\1/g' `hg mani`

It has been reviewed that all uses of allow_default_user=True are in places
where the there indeed wasn't any checking for default user before. These may
or may not be correct, but now they are explicit and can be spotted and fixed.

The few remaining uses of @NotAnonymous should probably be removed somehow.

users: remove code that is unused after most autocomplete has been switched to ajax

@mention support still require _USERS_AC_DATA as a global variable.

index: show repositories and repository groups in the same table

Having two different tables with their own paging and search gave a bad UI.
Instead, do like all other UIs that show directory content and show both
"folders" and "files" in the same list.

The rendering of repo groups is changed to use js data instead of a taking data
from an html table.

Repository groups are shoe-horned into the repository DataTable. The columns
are no perfect match - some of the existing columns are thus given an empty
default value.

controllers: drop unused totalRecords and startIndex

We don't want it just for testing.

codingstyle: trivial whitespace fixes

Reported by flake8.

backend: replace Pylons with TurboGears2

Replace the no-longer-supported Pylons application framework by TurboGears2
which is largely compatible/similar to Pylons.
Some interesting history is described at:
https://en.wikipedia.org/wiki/TurboGears

Changes by Dominik Ruf:
- fix sql config in test.ini

Changes by Thomas De Schampheleire:
- set-up of test suite
- tests: 'fix' repo archival test failure
Between Pylons and TurboGears2, there seems to be a small difference in the
headers sent for repository archive files, related to character encoding.
It is assumed that this difference is not important, and that the test
should just align with reality.
- remove need to import helpers/app_globals in lib
TurboGears2 by default expects helpers and app_globals to be available
in lib. For this reason kallithea/lib/__init__.py was originally changed
to include those files. However, this triggered several types of
circular import problems. If module A imported something from lib (e.g.
lib.annotate), and lib.helpers imported (possibly indirectly) module A,
then there was a circular import. Fix this by overruling the relevant
method of tg AppConfig, which is also hinted in the TurboGears2 code.
Hereby, the include of something from lib does not automatically import
helpers, greatly reducing the chances of circular import problems.
- make sure HTTP error '400' uses the custom error pages
TurboGears2 does not by default handle HTTP status code
'400 (Bad Request)' via the custom error page handling, causing a
standard non-styled error page.
- disable transaction manager
Kallithea currently handles its own transactions and does not need the
TurboGears2 transaction manager. However, TurboGears2 tries to enable it
by default and fails, throwing an error during application initialization.
The error itself seemed to be harmless for normal application functioning,
but was nevertheless confusing.
- add backlash as required dependency: backlash is meant as the WebError
replacement in TurboGears2 (originally WebError is part of Pylons). When
debug==true, it provides an interactive debugger in the browser. When
debug==false, backlash is necessary to show backtraces on the console.
- misc fixes

controllers: rename __before__ to _before in preparation of TurboGears2

__before__ in Pylons is called _before in TurboGears2. We can prepare this
rename already in Pylons-based Kallithea, so that the real TG2 migration
commit just changes the BaseController.

Since TurboGears2 _before can pass extra arguments, we add *args and
**kwargs parameters as well.

tg: minimize future diff by some mocking and replacing some pylons imports with tg

No actual tg dependency yet, just a temporary hack faking tg as an alias for
pylons.

Based on work by Alessandro Molina.

templates: properly escape inline JavaScript values

TLDR: Kallithea has issues with escaping values for use in inline JS.
Despite judicious poking of the code, no actual security vulnerabilities
have been found, just lots of corner-case bugs. This patch fixes those,
and hardens the code against actual security issues.

The long version:

To embed a Python value (typically a 'unicode' plain-text value) in a
larger file, it must be escaped in a context specific manner. Example:

>>> s = u'<script>alert("It\'s a trap!");</script>'

1) Escaped for insertion into HTML element context

>>> print cgi.escape(s)
&lt;script&gt;alert("It's a trap!");&lt;/script&gt;

2) Escaped for insertion into HTML element or attribute context

>>> print h.escape(s)
&lt;script&gt;alert(&#34;It&#39;s a trap!&#34;);&lt;/script&gt;

This is the default Mako escaping, as usually used by Kallithea.

3) Encoded as JSON

>>> print json.dumps(s)
"<script>alert(\"It's a trap!\");</script>"

4) Escaped for insertion into a JavaScript file

>>> print '(' + json.dumps(s) + ')'
("<script>alert(\"It's a trap!\");</script>")

The parentheses are not actually required for strings, but may be needed
to avoid syntax errors if the value is a number or dict (object).

5) Escaped for insertion into a HTML inline <script> element

>>> print h.js(s)
("\x3cscript\x3ealert(\"It's a trap!\");\x3c/script\x3e")

Here, we need to combine JS and HTML escaping, further complicated by
the fact that "<script>" tag contents can either be parsed in XHTML mode
(in which case '<', '>' and '&' must additionally be XML escaped) or
HTML mode (in which case '</script>' must be escaped, but not using HTML
escaping, which is not available in HTML "<script>" tags). Therefore,
the XML special characters (which can only occur in string literals) are
escaped using JavaScript string literal escape sequences.

(This, incidentally, is why modern web security best practices ban all
use of inline JavaScript...)

Unsurprisingly, Kallithea does not do (5) correctly. In most cases,
Kallithea might slap a pair of single quotes around the HTML escaped
Python value. A typical benign example:

$('#child_link').html('${_('No revisions')}');

This works in English, but if a localized version of the string contains
an apostrophe, the result will be broken JavaScript. In the more severe
cases, where the text is user controllable, it leaves the door open to
injections. In this example, the script inserts the string as HTML, so
Mako's implicit HTML escaping makes sense; but in many other cases, HTML
escaping is actually an error, because the value is not used by the
script in an HTML context.

The good news is that the HTML escaping thwarts attempts at XSS, since
it's impossible to inject syntactically valid JavaScript of any useful
complexity. It does allow JavaScript errors and gibberish to appear on
the page, though.

In these cases, the escaping has been fixed to use either the new 'h.js'
helper, which does JavaScript escaping (but not HTML escaping), OR the
new 'h.jshtml' helper (which does both), in those cases where it was
unclear if the value might be used (by the script) in an HTML context.
Some of these can probably be "relaxed" from h.jshtml to h.js later, but
for now, using h.jshtml fixes escaping and doesn't introduce new errors.

In a few places, Kallithea JSON encodes values in the controller, then
inserts the JSON (without any further escaping) into <script> tags. This
is also wrong, and carries actual risk of XSS vulnerabilities. However,
in all cases, security vulnerabilities were narrowly avoided due to other
filtering in Kallithea. (E.g. many special characters are banned from
appearing in usernames.) In these cases, the escaping has been fixed
and moved to the template, making it immediately visible that proper
escaping has been performed.

Mini-FAQ (frequently anticipated questions):

Q: Why do everything in one big, hard to review patch?
Q: Why add escaping in specific case FOO, it doesn't seem needed?

Because the goal here is to have "escape everywhere" as the default
policy, rather than identifying individual bugs and fixing them one
by one by adding escaping where needed. As such, this patch surely
introduces a lot of needless escaping. This is no different from
how Mako/Pylons HTML escape everything by default, even when not
needed: it's errs on the side of needless work, to prevent erring
on the side of skipping required (and security critical) work.

As for reviewability, the most important thing to notice is not where
escaping has been introduced, but any places where it might have been
missed (or where h.jshtml is needed, but h.js is used).

Q: The added escaping is kinda verbose/ugly.

That is not a question, but yes, I agree. Hopefully it'll encourage us
to move away from inline JavaScript altogether. That's a significantly
larger job, though; with luck this patch will keep us safe and secure
until such a time as we can implement the real fix.

Q: Why not use Mako filter syntax ("${val|h.js}")?

Because of long-standing Mako bug #140, preventing use of 'h' in
filters.

Q: Why not work around bug #140, or even use straight "${val|js}"?

Because Mako still applies the default h.escape filter before the
explicitly specified filters.

Q: Where do we go from here?

Longer term, we should stop doing variable expansions in script blocks,
and instead pass data to JS via e.g. data attributes, or asynchronously
using AJAX calls. Once we've done that, we can remove inline JavaScript
altogether in favor of separate script files, and set a strict Content
Security Policy explicitly blocking inline scripting, and thus also the
most common kind of cross-site scripting attack.

cleanup: remove SQLAlchemy session argument to action_logger

There's always a global SQLAlchemy session associated with the current
thread; using another session for a single function call does not make
any sense (as sessions cannot be mixed), unless the code works carefully
to ensure the two sessions (and all objects loaded from them) are kept
completely separate. Suffice to say that Kallithea does no such thing,
thus there's no need to pretend to support multiple concurrent sessions.

auth: simplify repository group permission checks

In practice, Kallithea has the 'group.admin' permission imply the
'group.write' permission, which again implies 'group.read'.

This codifies this practice by replacing HasRepoGroupPermissionAny
"perm function" with the new HasRepoGroupLevel function, reducing the
risk of errors and saving quite a lot of typing.

controllers: avoid setting request state in controller instances - set it in the thread global request variable

In TurboGears, controllers are singletons and we should avoid using instance
variables for any volatile data. Instead, use the "global thread local" request
context.

With everything in request, some use of c is dropped.

Note: kallithea/controllers/api/__init__.py still use instance variables that
will cause problems with TurboGears.

repo_groups: set c.active when displaying repo creation form errors through repo_group_edit.html

Writing failing tests revealed a crash.

db: rename RepoGroup.group_parent_id to parent_group_id

Also for consistency with the existing parent_group relationship.

db: PullRequest/Repository/RepoGroup/UserGroup: change 'user' to 'owner'

Rename the 'user' and 'user_id' fields on the four classes to something
more informative. The database column names remain unchanged for now;
a later Alembic script can fix the name of these and other columns to
match their Python name.

This might break rcextensions, though, and external scripts that use
the HTML form interface.

db: do case-insensitive explicit sorting of RepoGroup names

This does not change the implicit sorting enabled via __mapper_args__,
which is a bad idea anyway (and now deprecated), and will have to be
dealt with in a later changeset.

The use of __mapper_args__ implicitly adds sorting to every query of
RepoGroup objects throughout the code (including implicit queries via
relationships). For the relationships, __mapper_args can be replaced
with "order_by" on each individual relationship, and it's reasonably
straight-forward to identify every RepoGroup query throughout the code,
and add explicit sorting. But we don't really need that sorting most
of the time, so a better way forward may be to identify all the places
that actually needs the sorting, make it explicit there, and then kill
the __mapper_args__. (Anyway, future work.)

Turbogears2 migration: replace pylons.url by kallithea.config.routing.url

In preparation for the migration to Turbogears2, introduce a
kallithea.config.routing.url to replace pylons.url. The implementation is
basically the same: wrap around routes.url().

This change involves:
- a number of import statement changes
- fixing some tests in test_libs.py; to avoid duplication, the different
implementations of fake_url were grouped in one place.

This change was first proposed by Alessandro Molina in his initial
port. Following changes were made afterwards:
- move UrlGenerator from kallithea.lib.utils to kallithea.config.routing
- add documentation to UrlGenerator
- kallithea/lib/auth.py used url_for instead of url, for no apparent reason
so this was changed.
- fix libs tests
- rebase onto Pylons-based Kallithea first

controllers: remove pointless comments

These comments are mostly trivial and sometimes wrong. We don't want to
maintain or pretend we do.

auth: remove HasPermissionAll and variants

First, find all calls to HasPermissionAll with only a single permission
given, and convert to equivalent calls to HasPermissionAny.

Next, observe that it's hard to envision situations requiring multiple
permissions (of the same scope: global/repo/repo group) to be satisfied.
Sufficiently hard that there are actually no such examples in the code.

Finally, considering that (should it ever be needed) HasPermissionAll
can be trivially built as a conjunction of HasPermissionAny calls (the
decorators, too) with only a small performance impact, simply remove
HasPermissionAll and related classes and functions.

cleanup: replace redirect with WebOb exceptions

All redirect does is to log "Generating 302 redirect" with logging the actual
location and raise a WebOb HTTPFound exception, and the logging is redundant,
as WebOb exceptions and their status codes are already logged.

Instead, just raise the exception directly, which is both explicit and simpler
(and finally, gets rid of "return redirect" which never really returns).

cleanup: replace abort with WebOb exceptions

All abort does is to look up the matching WebOb exception and raising
that; so just raise it directly. WebOb exception names are also more
readable than HTTP error codes. (And finally, don't "return abort",
since abort never returns.)

spelling: fix inappropriate use of title case

These are not titles or labels, and should not be title cased.

cleanup: remove unused imports

Found with pyflakes.

cleanup: consistently use 'except ... as ...:'

Use the Python 2.6+ syntax instead of the old confusing 'except ..., ...'
syntax.

security: Fix HTML and JavaScript injection.

This fixes CVE-2015-1864

controllers: consistently use formfill.render with force_defaults=False

The inconsistency could cause confusion for developers. It seems to me like
force_defaults=False should be the default ... and apparently it was that in
older versions of formfill.

It could perhaps make sense for us to have a wrapper that added the defualt
values once, instead of repeating it all over ;-)

spelling: fix various typos

This commit fixes various typos or basic English grammar mistakes found by
reviewing the kallithea.pot file.

Full correction of sentences that are not very well formulated, like missing
articles, is out of scope for this commit. Likewise for inconsistent
capitalization of strings like 'Repository group'/'Repository Group'.

user: use h.person(obj.user) instead of h.person(obj.user.username) - don't fail if user is None

h.person prefer a user object anyway - just pass it obj.user and make sure
h.person doesn't crash on getting a None user.

Correct licensing information in individual files.

The top-level license file is now LICENSE.md.

Also, in various places where there should have been joint copyright holders
listed, a single copyright holder was listed. It does not appear easy to add
a link to a large list of copyright holders in these places, so it simply
refers to the fact that various authors hold copyright.

In future, if an easy method is discovered to link to a list from those
places, we should do so.

Finally, text is added to LICENSE.md to point to where the full list of
copyright holders is, and that Kallithea as a whole is GPLv3'd.

Second step in two-part process to rename directories.
This is the actual directory rename.