Recent submissions

Comment · 1 year ago
Java is supported, but currently in the pro version. Since JavaSSL is implemented in Java code, which runs in the Java VM and not exported as static symbols that can be uprobe'd, there is a bit more involved to generate a bridge between the JVM bytecode and static symbols that can be probed.
Comment · 1 year ago
Great idea!

On an unrelated note, your work has inspired most of my career in Solaris/Illumos/Linux systems and honestly this project likely wouldn't have happened if it wasn't for all of your books/blogs/projects to help me along the way. Thank you!

Comment · 1 year ago
The short answer is that we only have to calculate the offset per go version, no expensive runtime scanning is required.

The long answer is that the offsets are the byte alignment offsets for the go structs containing the pointers to the file descriptor and buffers. Fortunately we only have to calculate these for each version where the TLS structs within go actually change, so not even for every version. For instance, if a field is added, removed, or changes type then the location in memory where those pointers will be found changes. We can then calculate the actual offset at runtime where we know which architecture (amd64, arm64, etc) with a simple calculation. Within the eBPF probe, when the function is called, it uses pointer arithmetic to extract the location of the file descriptor and buffer directly.

Comment · 1 year ago
The main benefit is complete coverage. In production systems there are many different workloads with many different binaries, each with different build processes. Leveraging eBPF enables seeing everything on a system without having to adjust the build pipeline.
Comment · 1 year ago
Just run the qtap agent on whatever Linux machine has apps running on it and it will see everything through the kernel vs eBPF.

You can customize config and/or integrate with existing observability pipelines, but initially you just need to turn it on for it to work. No app instrumentation required.

Comment · 1 year ago
We have Go support, but it is not open sourced yet. Go is a bit more complicated but we were able to get it after some cave diving in the ELF formats. To give you a little insight on how this works, because Go is statically linked, we need to pull several different offsets of the functions we are going to hook into.

We do this by scanning every version of Go that is released to find offsets in the standard library that won't change. Then when we detect a new Go process, we use an ELF scanner to find some function offsets and hook into those with uprobes. Using both of these, we have all the information we need to see Go pre-encryption content as well as attribute it to connections and processes.

Comment · 1 year ago
Great point! Yes it supports both scenarios. Qtap scans the binary ELF (curl, rust, etc) and looks for the TLS symbols. If they were statically compiled the eBPF probes will be attached directly to the binary, if dynamically linked the probes will be attached to the symbols in the library (.so).
Comment · 9 years ago
Comment · 9 years ago
That's the highest requested feature! Should be available in Q1 of 2018.
Comment · 9 years ago
fixing now. Thanks for the heads up
Comment · 9 years ago
Comment · 9 years ago

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