Parsnip is currently in a beta release state and is intended for early adopters. Users may experience issues, bugs and missing features. Those experiencing difficulties with Parsnip should create a GitHub issue.

Parsnip is a program developed to assist in the parsing of protocols using the open source network security monitoring tool Zeek. Parsnip is specifically designed to be applied towards developing Industrial Control Systems (ICS) protocol parsers but can be applied to any protocol.

The Parsnip ecosystem consists of three parts:

1. A GUI interface designed provide a visual representation of a protocol's packet structure
2. JSON files in an intermediate language (IL) that is fed into the backend. This intermediate language is made up of a set of JSON structures using keywords for each key-value pair to indicate it's type.
3. A backend that performs processing on the parsnip IL files and outputs the spicy, zeek and event files necessary for a parser

• backend: folder containing the code for the backend; used for processing parsnip IL files to create zeek parsers
• docs: folder containing project documentation
• frontend: folder containing the code for the web frontend; used for creating parsnip IL files
• LICENSE.txt: code license file
• NOTICE.txt: code notice file
• README.md: this file

Please refer to docs/parsnip.md for more information on using Parsnip.

• Package creation may have some file permission issues. If a package does not install, check that the files in the testing/scripts directory are executable.
• Choices actions can currently only point to objects, not other types such as integers.
• Frontend functionality is limited. Specifically AND and OR conditionals, layer 2 parsing and the minus keyword need to be implemented in the intermediate language.
• Self-recursive types with multiple switches are not properly handled. This will be fixed in a later release.
• Zeek btest in the created package is limited to a basic availability test. Functionality for expanding btests has not been added.