Hi all,
being part of Commons Conservancy brought up yet another subject,
which is whether we should add a header with license information in
every file in the projects under idpy. This is not something done in
an abstract way, there is a specific format modelling this information
(see https://spdx.org/ and https://reuse.software/ - more specifically
https://reuse.software/practices/2.0/) Still, I find it problematic.
We want to open up the question to the wider community and consider
their thoughts on this. The forwarded message below is discussing this
subject. You can see the question we posed, the answer we got and my
comments. Feel free to tell us what you think on this.
---------- Forwarded message ---------
Date: Thu, 16 May 2019 at 09:56
> ---------- Forwarded message ----------
> Date: May 8, 2019, 8:15 AM -0700
>
> > Why does CC think having a single license file per project is
> > insufficient? Our thought is that if we can avoid adding a header to
> > every single file, that would be nice, esp. given we already have this
> > info in the license file and we have the Note Well.
>
>
> this is not just our opinion, but something that is an industry and
> community standard for legal compliance these days. When companies like
> Siemens, Samsung or Honeywell use some code in one of the hundreds or
> thousands of devices and systems in their product line, they need to be
> able to provide the correct license and a download of the exact version.
> This means machine readability too.
>
I've actually observed the opposite of that. Communities abandon the
"license in every file" model, and just use a single LICENSE file in
the root of the project. The LICENSE file contains license
information, that is, it is not a single license but it has exception
sections and so on.
> To quote from https://reuse.software/practices/2.0/ :
>
> Scroll to the section "2. Include a copyright notice and license in each
> file"...
>
> "Source code files are often reused across multiple projects, taken from
> their origin and repurposed, or otherwise end up in repositories where
> they are separate from its origin. You should therefore ensure that all
> files in your project have a comment header that convey that file’s
> copyright and license information: Who are the copyright holders and
> under which license(s) do they release the file?
>
Continuing from above, the standardization of package-management
formats and tools has helped exactly with that: to avoid distribution
of single files, and instead provide packages and modules. It is bad
practice and considered a hack to copy files. Nobody liked that model
and everyone is moving away; it is unstructured, it becomes
unmanageable and it will cause problems.
> It is highly recommended that you keep the format of these headers
> consistent across your files. It is important, however, that you do not
> remove any information from headers in files of which you are not the
> sole author.
>
> You must convey the license information of your source code file in a
> standardised way, so that computers can interpret it. You can do this
> with an SPDX-License-Identifier tag followed by an SPDX expression
> defined by the SPDX specifications."
>
> (the text goes on for a while after this, to clarify the point but this
> is the basic gist of it)
>
> There is a nice Python tool to check:
>
> https://github.com/fsfe/reuse-tool
>
> I hope this makes sense
>
Well, it does not make complete sense. We're talking about licensing a
project. A project is not just code; there are data files (html, xml,
yaml, json files), binary files (archives/zip, images, audio, video,
etc), text files (configs, ini-files, etc) all "not-code". How do you
mark those files? Does the LICENSE file need a license-header? The
json format does not define comments, how do you add a header there?
If a binary file does not get a license header, why should a file with
code get one?
I would expect there to be a way to have the needed information
unified. If the files themselves cannot provide this information it
has to be external; thus the LICENSE file. If someone is worried about
somebody else re-using single files that do not have license
information (a python file, a png image, etc) there is really nothing
you can do (the DRM industry has been trying to solve for a long time;
and still your best bet is "social DRM").
Since, we're developing on open source with a permissive license, even
if someone does that, should we be happy that someone is actually
using what we built or sad that the files they copied did not have a
license header? And if they include the license information of that
copied file in their project's LICENSE file, is this solved?
Having pointed these contradictions, I am thinking that the "license
in every file" model seems to be a step backwards. It is introducing
overhead and does not really solve the problem, while at the same time
it enables a culture of bad practice (copying files around).
Cheers,
--
Ivan c00kiemon5ter Kanakarakis >:3
Hello everyone,
there has been a report on incident-response at idpy.org about a security
issue in PySaml2.
Alexey Sintsov and Yuri Goltsev from HERE Technologies reached out and
reported a XML Signature Wrapping (XSW) vulnerability. The issue
affects responses with signed assertions. PySaml2 can be tricked to
think that an assertion had been signed and use the assertion
information, when in reality the Signature points to another part of
the xml document that is controlled by another party.
The issue was assigned CVE-2020-5390 and is now fixed in the latest
pysaml2 release.
The relevant code commit that fixes is the issue:
https://github.com/IdentityPython/pysaml2/commit/5e9d5acbcd8ae45c4e736ac521…
Release v5.0.0 contains more changes, including:
- Add freshness period feature for MetaDataMDX
- Fix ipv6 validation to accommodate for addresses with brackets
- Fix xmlsec temporary files deletions
- Add method to get supported algorithms from metadata
- Add mdstore method to extract assurance certifications
- Add mdstore method to extract contact_person data
- Start dropping python2 support
Pointers to the release with changelog and more information, below:
- the relevant release commit:
https://github.com/IdentityPython/pysaml2/commit/f27c7e7a7010f83380566a219f…
- the github release:
https://github.com/IdentityPython/pysaml2/releases/tag/v5.0.0
- the pypi package:
https://pypi.org/project/pysaml2/5.0.0/
+ + + + + + + +
In more detail, regarding the XSW vulnerability:
libxml2 follows the xmldsig-core specification. The xmldsig
specification is way too
general. saml-core reuses the xmldsig specification, but constrains it to use of
specific facilities. The implementation of the SAML specification is
responsible to
enforce those constraints. libxml2/xmlsec1 are not aware of those
constraints and thus
process the document based on the full/general xmldsig rules.
What is happening is the following:
- xmldsig-core allows the signature-information and the data that was
signed to be in
different places. This works by setting the URI attribute of the
Reference element.
The URI attribute contains an optional identifier of the object
being signed. (see
"4.4.3 The Reference Element" --
https://www.w3.org/TR/xmldsig-core1/#sec-Reference)
This identifier is actually a pointer that can be defined in many
different ways; from
XPath expressions that need to be executed(!), to a full URL that
should be fetched(!)
in order to recalculate the signature.
- saml-core section "5.4 XML Signature Profile" defines constrains on
the xmldsig-core
facilities. It explicitly dictates that enveloped signatures are the
only signatures
allowed. This mean that:
* Assertion/RequestType/ResponseType elements must have an ID attribute
* signatures must have a single Reference element
* the Reference element must have a URI attribute
* the URI attribute contains an anchor
* the anchor points to the enclosing element's ID attribute
xmlsec1 does the right thing - it follows the reference URI pointer
and validates the
assertion. But, the pointer points to an assertion in another part of
the document; not
the assertion in which the signature is embedded/enveloped. SAML
processing thinks that
the signature is fine (that's what xmlsec1 said), and gets the
assertion data from the
assertion that contains the signature - but that assertion was never
validated. The
issue is that pysaml2 does not enforce the constrains on the signature
validation
facilities of xmldsig-core, that the saml-core spec defines.
The solution is simple; all we need is to make sure that assertions
with signatures (1)
contain one reference element that (2) has a URI attribute (3) that is
an anchor that
(4) points to the assertion in which the signature is embedded. If
those conditions are
met then we're good, otherwise we should fail the verification.
--
Ivan c00kiemon5ter Kanakarakis >:3
Hi Leif,
I added 2 pipes to buildin.py:
- publish_html creates static HTML views of IDPs and SPs, using XSLT based on Peter Schober’s alternative to MET;
- publish_split: similar to store, but added validUntil and creates signed XML-file per EntityDescriptor. This can be consumed dynamically by ADFS in an IDP role.
I put it directly into buildin.py because it shares some code with the sign pipe. Is this viable from your PoV - if yes, I would make an PR.
Cheers, Rainer
Notes from Ivan:
For idpy-oidc, work is being done around the support for native clients,
especially supporting variable ports for redirect URIs.
Along with that work, more checks are added around the validity of a
redirect URI. The redirect URI should be a URL as it will become part of
the Location HTTP header. The standard python libraries (urllib.parse) do
not perform any kind of validation and will even accept ports with letters.
Additionally, we need to properly check for the URI scheme. I'd like us to
have a denylist (or an allowlist) for schemes. Schemes like "data://" and
"javascript://" should be denied.
On another front, I have been working to generate test data with the Faker
library. It integrates with pytest too. We can use that library to generate
randomized data that follow some specific format. Given a seed, we can
recreate the same data. A few useful references here:
- https://faker.readthedocs.io/
-https://faker.readthedocs.io/en/stable/providers.html
-https://faker.readthedocs.io/en/stable/communityproviders.html
Matthew brought up the topic of tidying up the satosa repo. This relates
to https://github.com/IdentityPython/SATOSA/pull/454. We agreed to separate
the configuration changes from changes after applying the settings (big
changes on the source code etc). We should agree when to apply the changes;
certainly after the new release that is to come.
*Idpy meeting 14 May 2024*
Attendees: Johan W, Johan L, Shayna, Ivan, Roland, Matthew E.
0 - Agenda bash
1 - Project review
a. General -
b. OIDC libraries - https://github.com/IdentityPython (idpy-oidc,
JWTConnect-Python-CryptoJWT, etc)
- a while ago: demo of digital wallet ecosystem
- Roland was asked what would an identity federation look like using
the same type of setup? Roland has something running. Will
allow a person
who wants to see what the federation is to grab a number of
docker images
to run their federation. Roland is working on the recipes for
this, but
someone else is making the actual docker images.
- digital wallets - Roland set up an experiment - wallet connects
to SATOSA frontend credential issuer, gets redirected to backend
to talk to
SAML Idp, which returns attributes. Then when the wallet connects to the
credential endpoint, it gets a credential with the attributes
that the SAML
IdP released.
- requires persistent storage for the attributes - when you get to
the credential endpoint, SATOSA frontend doesn't know
anything about them
otherwise
- when the wallet asks for information, it is expected to provide
a credential type (personal, DL, etc). Discussion is going on about
specifying credential types that eduGain returns. Could ask
for a specific
type of information - such as higher ed - i.e. affiliation
(not things like
courses, degrees)
- Roland asked about this (credential types) in Slack - Ivan asked
if we know what the payload looks like? - not yet. Still
under discussion.
- Ivan is looking at native oidc clients - spec says "when this
uri is met, this application opens". When uri is localhost and it is a
local client, the port number can be anything. In oidc we check
for a port
exact match. This needs to be fixed - Ivan will describe it in an issue.
Breakdown uri into parts, sure make domain is correct, make sure path is
correct, but port....
- During oidc registration there are references to this claim which
is the client type option which separates confidential information from
public clients. But some people are using it to say this is a native app,
or a web application. The convention seems to be that native clients are
public clients. This is still a mystery - what this client type
with native
means, and web.
- Nikos PR *Draft* - resource indicator, how and when we set the
audience in generated tokens
https://github.com/IdentityPython/idpy-oidc/pull/102
- Roland also has a PR
https://github.com/IdentityPython/idpy-oidc/pull/101 - import export
module - now works for the complete application structure. Ivan
will review.
c. Satosa - https://github.com/IdentityPython/SATOSA
- Kristof - meeting to close off PR about the base url that can be used
- lots of pending things and things to be fixed.
- Ivan wants to make a check for the optional dependencies and then
put out a new release, then move on. Approximate timeframe - hopefully
within this week.
d. pySAML2 - https://github.com/IdentityPython/pysaml2
- A new PR https://github.com/IdentityPython/pysaml2/pull/961 - uses
xmlsec module instead of xmlsec1 binary. Created new crypto backend -
extended pyxmlsecurity to do encryption with xmlsec module.
Could be a new
crypto backend and could also do the signing - can xmlsec module do the
signing directly? Possibly use this to replace xmlsec1 binary.
Issues with
xmlsec1 binary after version update - had to do updates on our side to
parse output as the outputs changed. The module takes care of this. There
are a few tricky things:
- xmlsec1 binary - command line options in place to not do any
additional stuff like going out to the web to find
certificates. Some of
these options are missing in the module. We want to make sure
it uses the
cerificates we provide and not something else. Within the xml
payload there
is a certificate and this is the one used instead of the one from the
metadata.
- Matthew question - xmlsec module - is it python standard or
third party? Answer - third party. How well has this been
tested? Xmlsec1
is battle tested. Ivan - it is C bindings for the xmlsec library.
- Tricky thing in pysaml2- have to specify a file in a filesystem.
Serverless use cases where that type of config is not
readily available
require hacking up some way to generate that file before
you can configure
the pysaml2 client- would this new backend give a new way
to configure that
keying material? Ivan - Doesn't change the options for the
keying material.
But currently with xmlsec1 binary we invoke from the
command line and pass
in pointers to files. With new xmlsec module - won't have
to do that -
things are loaded from memory. But keys for satosa and
pysaml2 entities
need to be there. Trick: you can store those material as
base64 strings
within params - then entry point can unpack and store them
on docker file
system.
- Ivan has used another library to do signing parts - could
leverage this to clean up parts of the code.
- These can be optional choices - doesn't have to replace what is
already there
- There are some smaller things to looks into, and a few big ones
which need focus
- https://github.com/IdentityPython/pysaml2/pull/924 Configurable
options for the encryption algorithms
- Also some maintenance - taking care of date/time/locations -
deprecations in certain methods
- Need to merge a few things around how tests are run, pre-commit
configurations, etc.
e. Any other project (pyFF, djangosaml2, pyMDOC-CBOR, etc)
- pyeleven - important project - a release or maybe tag to make builds
more predictable. Pypi would be nice but not required.
- Victor was building a project around CA and parts of pyeleven - his
code should be under the SUNET repos.
- Should do a new release and make sure things are up to date - do
a check on the dependencies.
- pyff - issues -
- https://github.com/IdentityPython/pyFF/issues/265 - error when
trying to load certificates (which may not be well-formatted
- unclear).
This should be an easy fix.
- https://github.com/IdentityPython/pyFF/issues/264 - trickier
issue - taking the signature of metadata document when pyff uses
configuration with xrd file. Ivan is not familiar with using
it this way.
Need to understand why the check is being skipped. It worked properly
before but it not working correctly now. Did Matthew say he
was looking at
this? Out put of pyff is given to thiss.io
- SAMLtest test idp - gone - SATOSA image needs to be fixed.
https://github.com/IdentityPython/satosa-docker/issues/10
2 - AOB
- A topic for the board: There is a tension between delivering tools,
working on the proxy, and working on the services that support the proxy.
Need more people to be involved in the reviews. Issues are very complex, so
it is hard to find people to address things beyond the few that have the
overall knowledge.
