dom-examples VS OpenSSL

If you have a moment, take a look through the Web API docs from MDN. I guarantee you will find something new that solves a problem you needed to build your own solution for in the past.

This is a problem! Ideally, your backend application should be platform-independent by following the standardized Web API. This way, you could run it across most JavaScript platforms.

Fonte: MDN web docs

References MDN Chrome Docs

> if writing a browser today is in fact easier than both writing AND maintaining a browser a decade back.

Probably not. Yeah we have web standards and some idea of how to architect it, but the total set of APIs and HTML/CSS/JS features a browser supports is probably changing faster than the Ladybird team can actively implement it. The API surface is just impossibly large compared to 10 or 15 years ago. Look at all of these: https://developer.mozilla.org/en-US/docs/Web/API

I added polyfills for the Web APIs used in the React code.

In addition to pure JavaScript, there are hundreds of Web APIs documented at MDN. These APIs cover everything from the DOM to Web Workers with great detail.

I'm reading MDN Web Docs on Web APIs. There are two basic sections, specifications and interfaces.

The biggest difference is usually found in what non-ECMAscript standard JS web apis or features are implemented in different browsers. Here's a list of typical web APIs, and for many of them there is a compatibility table at the bottom detailing which browser do or do not support it. https://developer.mozilla.org/en-US/docs/Web/API

If you're going to use a custom local domain name, you might as well use a self-signed SSL certificate. I'll use OpenSSL for this:

Are you facing the notorious ERR_OSSL_EVP_UNSUPPORTED error in your Node.js applications? This error is a common stumbling block that occurs due to changes in cryptographic operations handling introduced with Node.js version 17. The root of the problem lies in the default configuration of OpenSSL in newer Node.js versions, which restricts the use of certain algorithms. Fortunately, there are effective solutions to overcome this error, ensuring your development process remains smooth and uninterrupted.

ENV OPENSSL_PREFIX=/opt/openssl ENV SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt WORKDIR /tmp RUN git clone --branch OpenSSL_1_0_2n https://github.com/openssl/openssl.git RUN cd openssl RUN ./config shared --prefix=$OPENSSL_PREFIX --openssldir=$OPENSSL_PREFIX/ssl RUN make RUN make install RUN rvm install 2.6.0 -C --with-openssl-dir=$OPENSSL_PREFIX ENV PATH /usr/local/rvm/bin:$PATH RUN rvm --default use ruby-2.6.0 ENV PATH /usr/local/rvm/bin:/usr/local/rvm/rubies/ruby-2.6.0/bin:$PATH ENV GEM_HOME /usr/local/rvm/rubies/ruby-2.6.0/lib/ruby/gems/2.6.0

Today, April 7th, 2024, marks the 10-year anniversary since CVE-2014-0160 was published. This security vulnerability known as "Heartbleed" was a flaw in the OpenSSL cryptography software, the most popular option to implement Transport Layer Security (TLS). In more layman's terms, if you type https:// in your browser address bar, chances are high that you are interacting with OpenSSL.

At this point I pretty much understand the entire process on how the xz backdoor came to be: its execution stages, extraction from binary "test" files etc. But one thing puzzles me: how can the ifunc mechanism be used to replace something like RSA_public_decrypt? Granted this probably stems from my lack of understanding of ifunc, but I was under the impression that in order for the ifunc mechanism to work in your code, you have to explicitly mark specific function with multiple implementations with __attribute__ ((ifunc ("the_resolver_function"))). Looking at the source code of the RSA function in question, ifunc attribute isn't present:

https://github.com/openssl/openssl/blob/master/crypto/rsa/rsa_crpt.c#L51

So how does the backdoor actually replace the call? Does this means that the ifunc mechanism can be used to override pretty much anything on the system?

OpenSSL and Go crypt/tls has no support yet, so none of the webservers that depend on them support it. Apache, Nginx, and Caddy, they all need upstream ECH support first.

- https://github.com/openssl/openssl/issues/7482

- https://github.com/openssl/openssl/pull/22938

- https://github.com/golang/go/issues/63369

If I'm understanding the draft correctly, I think the webserver you're hosting your sites on would need it implemented as it requires private keys and ECH configuration. In the example of nginx since it uses openssl, openssl would need to implement it. I found an issue on their Github but it's still open: https://github.com/openssl/openssl/issues/7482