rsyslog 3.19.0 released – world’s first syslog-transport-tls implementation

I am very pleased to announce rsyslog 3.19.0.

It is the first release that natively supports TLS for plain TCP syslog. Actually, it is the world’s first implementation of the upcoming syslog-transport-tls IETF standard. As this standard is not yet finished, the implementation is obviously experimental.

Native TLS is a big improvement over existing functionality. For example, rsyslog can now be used without the help of stunnel, which relieves us of some problems from those configurations. To the best of my knowledge, rsyslog is the first open-source syslogd offering TLS support natively.

The current TLS functionality is limited to the bare minimum. During the next few weeks, I will improve it based on my own spec and feedback (hopefully received). My hope is to have a production-grade implementation by summer at latest. Please note rsyslog’s premium and ultra-reliable RELP protocol does not yet support TLS (but can be used with stunnel without the real problems legacy tcp had with it). My plan is to let TLS mature with legacy syslog and then move it to RELP. Thus I can limit my development to one major use case, which I think will facilitate things.

There is some documentation on how to use the new TLS mode:

Currently, TLS is provided via GnuTLS. As I outlined earlier on the list, GnuTLS offered much more support to getting started (documentation and sample-code wise). I will focus on GnuTLS until I am fully satisfied with the TLS implementation). I’ll then see that I can also integrate NSS. Advise in this regard would be highly welcome, so if you have some knowledge in this area, please contribute.

In order to support TLS (and multiple libraries!), a major rewrite of the networking components has been done. Rsyslog now supports a so-called “network streams” (netstreams) driver interface. This interface enables app-level functionality (like the legacy tcp syslog sender and receiver) to work with dynamically selectable netstream drivers (like plain (unencrypted) TCP) and TLS). This interface will enable rsyslog to utilize other TLS drivers (and even other protocols) in the future. Different drivers can even be used concurrently.

Rsyslog now has been split into a runtime system and tools (with currently rsyslogd being the only tool). This design will further strengthen modularization and help make rsyslog functionality available in small parts.

Finally, the RFC 3195 input has been rewritten in the form of an input plugin. It can now be build as part of the normal build procedure.

Please note that there were a couple of major changes. I expect the initial 3.19.0 to be quite Unstable. I recommend it for testing environments, only. Even those parts that were not directly touched may have become a bit destabilized due to the runtime split. So please use it with care. Feedback, however, would be more than welcome, because I need to start somewhere to stabilize this release. That can only be done with your help. So please use it on test systems, try to break it and file bug reports when it fails.



File your bug reports here ;) :

I hope this release is useful. Feedback is much appreciated.