brimcap

brimcap

A command line utility for converting pcaps into the flexible, searchable Zed data formats as seen in the Zui desktop app and Zed commands.

Quickstart

1. Install brimcap
2. Have a pcap handy (or download a sample pcap)
3. Run brimcap analyze

   brimcap analyze sample.pcap > sample.zng
   

4. Explore with zq

   zq -z 'zeek:=count(has(_path)), alerts:=count(has(event_type=="alert"))' sample.zng
   

Usage with Zui desktop app

brimcap is bundled with the Zui desktop app. Whenever a pcap is imported into Zui, the app takes the following steps:

1. brimcap analyze is invoked to generate logs from the pcap.

2. The logs are imported into a newly-created pool in Zui's Zed lake.

3. brimcap index is invoked to populate a local pcap index that allows for quick extraction of flows via Zui's Packets button, which the app performs by invoking brimcap search.

If Zui is running, you can perform these same operations from your shell, which may prove useful for automation or batch import of many pcaps to the same pool. The Custom Brimcap Config article shows example command lines along with other advanced configuration options. When used with Zui, you should typically use the brimcap binary found in Zui's zdeps directory (as described in the article), since this version should be API-compatible with that version of Zui and its Zed backend.

Brimcap Queries

Included in this repo is a queries.json file with some helpful queries for getting started and exploring Zeek and Suricata analyzed data within the Zui app.

To import these queries:

1. Download the queries.json file to your local system
2. In Zui, click the + menu in the upper-left corner of the app window and select Import Queries...
3. Open the downloaded file in the file picker utility

The loaded queries will appear in the "QUERIES" tab of Zui's left sidebar as a new folder named Brimcap.

Standalone Install

If you're working with brimcap separate from the Zui app, prebuilt packages can be found in the releases section of the brimcap GitHub repo.

Unzip the artifact and add the brimcap directory to your $PATH environment variable.

export PATH="$PATH:/Path/To/brimcap"

Included Analyzers

brimcap includes special builds of Zeek and Suricata that were created by the core development team at Brim Data. These builds are preconfigured to provide a good experience out-of-the-box for generating logs from pcaps using brimcap. If you wish to use your own customized Zeek/Suricata or introduce other pcap analysis tools, this is described in the Custom Brimcap Config article.

Build From Source

To build from source, Go 1.21 or later is required.

To build the brimcap package, clone this repo and run make build:

git clone https://github.com/brimdata/brimcap
cd brimcap
make build

make build will download the prebuilt/preconfigured Zeek and Suricata artifacts, compile the brimcap binary and package them into build/dist.

The executables will be located here:

./build/dist/brimcap
./build/dist/zeek/zeekrunner
./build/dist/suricata/suricatarunner

Having a problem?

Please browse the wiki to review common problems and helpful tips before opening an issue.

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