About secnote

A tool to help mark sections in code as security critical or build code flows, all from within the code itself.

Building

platforms

secnote should build on Linux distros like Ubuntu and Debian, on OpenBSD and on MacOS.

requirements

• libbsd-dev (on linux)
• openssl / libressl
• pkg-config

build

$ make $ make install

How

A secnote is opened with a @secnote-open marker. The open marker must include a topic and id.

/* @secnote-open topic=a-topic id=unique-id-in-topic */

The note is closed with a @secnote-close marker.

/* @secnote-close */

A note can have a weight attached to it. This is used by secnote for ordering the notes when multiple exist in the same topic.

To do so, specify the weight after the topic name:

/* @secnote-open topic=a-topic:100 ... */

Show

When running the tool without options on input files or directory it will gather information about the notes found and display them on stdout.

$ secnote .

You can also use options to display just a list of topics.

$ secnote -l src include

Or include all relevant locations.

$ secnote -lf sys kern fs

Verify

The tool allows the notes to be dumped into a simple text-based database format, which allows a developer to verify these secnotes against new versions of the source code to see what security critical code has been altered.

Create a secnote:

$ secnote -d proj_1_0_0 > secnote.txt

Verify the note against a new release:

$ secnote -v secnote.txt proj_1_0_2

You can also run secnote between 2 copies of the source:

$ secnote -d proj_1_0_0 | secnote -p1 -v - proj_1_0_2

Contribute

Send patches to joris@coders.se.

Caveats

It is hard to classify certain parts of code as security critical while leaving out other parts.

Security encompasses the entire code base.

Secnote can make it easier to digest code and understand which parts of it relate to security or potentially even are security critical without intimate understanding of the code.

As with everything related to comments and documentation, if it falls out of touch with reality it will become useless and could even turn into a security risk.

Only accepts .c, .h and .py files, hackable though.

License

ISC licensed, created by Joris Vink.