I initially wrote jstructural as a set of XSLT stylesheets. That quickly became unmaintainable as the complexity of the stylesheets increased. I rewrote them in Java. I eventually got tired of writing documentation in XML (I didn't know that better XML editors existed) so I ended up wanting to add the ability to write documents as S-expressions.
The right way to do this was to redesign jstructural so that it defined
a core AST type and added multiple parsers that all
produced values of this core type. Converting between documents of different
types would then be a matter of parsing using one syntax, and then serializing
the AST using another.
The most natural way to express an AST is as a large algebraic data type.
Java doesn't have direct support for these yet (although it's slowly getting
them via Project Amber). I therefore
looked at other JVM languages that did support them, and the choice was either
Scala or Kotlin. I
chose Kotlin, after multiple nasty experiences with Scala. kstructural
was born.
Fast forward to the present day, and I'm utterly sick of working on Kotlin code. The tools are slow. Compilation is slow. The people in charge of the ecosystem think devolving to special snowflake imperative build tools like Gradle is a good idea.
I'm going to do a new Java implementation of the structural language,
and I'm probably going to redesign the language to make it even easier
to implement. Nowadays, XML editing is fast and painless thanks to various
tools (with real-time validation errors). XOM is essentially
unmaintained, so I'll replace the XML parsing code with an efficient SAX
parser (and actually get lexical information in the parsed AST, unlike with
XOM).
I've enabled TLS on all io7m.com domains.
I'm using certificates from CaCert.org. These aren't trusted by all browsers, but I don't care all that much. If trust becomes a serious issue at some point, I'll buy real TLS certs. I PGP sign all text on the server anyway, so anyone that really cares about checking to see if some nefarious third party has changed the data in transit can do so, albeit manually.
No, I'm not using Let's Encrypt. I've looked into it several times and I just can't get around the fact that it requires a huge number of moving parts and that the average ACME client requires a ridiculous level of privileges to work properly: If you want any possibility of security, this is what it takes to get it.
At a minimum:
The client has to be able to make connections to a remote server
in order to download an extremely security-critical bit of data
(the certificate). If this step fails for any reason (the remote
side being unavailable, breakage in the client), the existing
certificate expires and the https service is dead.
The client has to be intelligent enough to know when to try
to get a new certificate. When is the right time? Who knows. Trying
to request a new certificate a minute before the current one expires
is suicidally reckless. Trying to do it the day before might be
acceptable, but what if it goes wrong? Is a day long enough to try
to fix a problem in something as gruesomely complex as the average
ACME client? The availability of your https service essentially
becomes tied to the availability of the ACME server. This wouldn't
be so bad if the update was a yearly thing and could be planned for,
but LE certificates are valid for 90 days.
The client has to be able to write to the directory being served
by the http server in order to be able to respond to challenges.
If the client is compromised, it has the ability to trash the
served web site(s). I run my services in a highly compartmentalized
manner, and having to allow this would be horrible. There are other
challenge types, such as publishing a DNS
record containing a response to a challenge, but those have the
same problem of what should be an unprivileged program having to
cross a security boundary and threatening the integrity of another
service's data.
The client has to be able to write to the http server's
configuration data (in order to publish the new certificate).
Again, if the client is compromised, it can trash the http
server's configuration. If the update fails here, the existing
certificate expires and the https service is dead.
Assuming that the client actually does manage to respond to
a challenge and get a certificate issued, and does actually
manage to write that certificate to the filesystem, the problem
then becomes getting the https server to use it. Most servers
read certificates once on startup and don't reread them. Therefore,
the client needs privileges to restart the server. This is
totally unacceptable; no service should ever be able to
forcefully restart another.
There are so many possible points of failure and every single one
results in a broken https service at best, or a system compromise
at worst. I'm vaguely surprised at how little in the way of criticism
I've seen online of the complexity of Let's Encrypt given the
usual reaction of information security experts to any new software
system. To paraphrase Neal Stephenson, the usual reaction is to crouch
in a fetal position under a blanket, screaming hoarsely that the new
system is way too complex and is a security disaster. I have to wonder
how many unpublished attacks against the ACME protocol there are out
there.
Contrast this to a typical TLS certificate provider: I download a
text file once a year and put it on the server. I then restart the
https service. Done. No extra software running, no other points
of failure.
The Maven JavaDoc plugin 3.0.0 is finally ready for release. This means that I can migrate 60+ projects to Java 9 and finally get the new versions pushed to Central.
Big thanks to Robert Scholte who worked hard to ensure that everything worked properly, and even got my rather unusual usage of the plugin (aggregating documentation into a single module) working as well.
I've been anxiously awaiting the 3.0.0 release of the
maven-javadoc-plugin
for weeks, and in an ironic twist of fate, I'm now responsible for delaying
the release even further.
I found two rather nasty bugs in the version
that was to become 3.0.0, but submitted a
fix
for the first and had it merged. The second problem
seems like it's going to take rather more work to fix
though, and my message asking for implementation advice to the
javadoc-dev
list is currently sitting in a moderation queue.