phil-fly / jarm-go

A Go implementation of JARM

jarm-go

Warning: This project is archived and is now read-only. Feel free to fork this as needed.

This is a Go implementation of JARM.

jarmscan

To install jarmscan, download a binary from the releases page or install using go install github.com/hdm/jarm-go/cmd/jarmscan@latest.

To run a scan, provide a list of targets. The following examples are all supported:

• jarmscan www.example.com
• jarmscan -p 443,8443 192.168.0.1
• jarmscan -p 1-1024 https://www.example.com/
• jarmscan -p 443,465,993,995,8443,9443 192.168.0.0/24
• jarmscan 192.168.0.1:8443
• jarmscan 192.168.0.1,443

The -q option can be used to disable verbose output and the -w parameter can be used to increase the worker count.

The -p option allows port lists and port ranges to be specified in a form similar to Nmap.

jarm

To use the jarm-go library from a Go application please review the Fingerprint() function in the cmd/jarmscan/main.go code.

The basic process involves:

• Creating a list of probes for a given host and port using GetProbes(). The host is sent as part of the client probe.
• Building each individual probe in the order they are returned using BuildProbe().
• Opening a connection to the host and port and sending the probe.
• Receiving the response (up to 1484 bytes). Receiving more or less can change the hash.
• Parsing the Server Hello from the received data using ParseServerHello().
• Calculating the JARM hash using RawHashToFuzzyHash().