ccache VS OpenSSL

# Download and install ccache for faster compilation wget https://github.com/ccache/ccache/releases/download/v4.8.3/ccache-4.8.3.tar.xz tar -xf ccache-4.8.3.tar.xz pushd ccache-4.8.3 cmake . make -j $CPUS make install popd # Install NumPy, a dependency for PyTorch dnf install -y numpy # Install Python typing extensions for better type-checking sudo -u ec2-user pip3 install typing-extensions # Clone PyTorch repository and install from source git clone --recursive https://github.com/pytorch/pytorch.git pushd pytorch python3 setup.py install popd # Refresh the dynamic linker run-time bindings ldconfig # Install additional Python libraries for PyTorch sudo -u ec2-user pip3 install sympy filelock fsspec networkx

> What can I use to cache with MSVC that isn't Incredibuild?

Ccache works, but if you use the Visual Studio C++ compiler you need to configure your build to be cacheable.

https://github.com/ccache/ccache/wiki/MS-Visual-Studio

That ecosystem now is too young. All these things must be configured by an automatic installer. Packages and pods need to be tested before release, etc. Previous was 80 min compilation time of the Firestore package. Solved with https://ccache.dev/. But why Dart developers must know, how to install and configure object cache for C++ compilers?

Related

https://github.com/icecc/icecream - another option that does what distcc does, but aimed at a somewhat different use case.

https://ccache.dev/ - a similar idea but provides caching of build outputs instead of distributing builds. You can use it together with distcc to achieve even better performance.

> All those big changes introduce commits that make git bisect generally slower.

Bisection search is log2(n) so doubling the number of commits should only add one more bisection step, yes?

> Which might be awful if you also have some C code to recompile at every step of bisecting.

That reminds me, I've got to try out ccache (https://ccache.dev/ ) for my project. My full compile is one minute, but the three files that take longest to compiler rarely change.

I worked with the internals of this some 16 years ago, maintaining a customized version at Zeugma Systems. Some change of mine was reworked by someone and upstreamed:

https://github.com/ccache/ccache/commit/e8354384f67bc733bea5...

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

I confirmed that the systm was on 1.1.1f with openssl version command. Hmm...... I check the openssl version in the repo with apt list... LOL package names wernt helpful. finally went to the repo pages and found that its still on 1.1.1f, https://launchpad.net/ubuntu/+source/openssl. Meenwhile I looked up the version history on https://www.openssl.org/ and saw that 1.1.1v was released at the beginning of this month... ok. I can understand it it was out less then 30 days. I looked up when f came out, end of MARCH 2020. NEARLY 3-1/2 YEARS