dnsgrab

This is a simple Go library and CLI tool that allows you to retrieve DNS servers from one or multiple hosts. When querying domains, the library incorporates a curated list of public resolvers from the publicresolvers library, expanding the available options for DNS resolution alongside the ability to provide your own custom resolvers using appropriate flags.

Installation

Go

go install github.com/root4loot/dnsgrab/cmd/dnsgrab@latest

Docker

git clone https://github.com/root4loot/dnsgrab.git && cd dnsgrab
docker build -t dnsgrab .
docker run -it dnsgrab -h

Usage

Usage: ./dnsgrab [options] (-h <host>|-i hosts.txt)

TARGETTING:
   -h,   --host          target host (comma separated)
   -i,   --infile        file containing hosts (newline separated)

CONFIGURATIONS:
   -r,  --resolvers      file containing list of resolvers   
   -c,  --concurrency    number of concurrent requests       (Default: 10 requests)
   -t,  --timeout        max request timeout                 (Default: 3 seconds)
   -d,  --delay          delay between requests              (Default: 0 milliseconds)
   -dj, --delay-jitter   max jitter between requests         (Default: 0 milliseconds)

OUTPUT:
   -o,  --outfile        output results to given file
   -s,  --silence        silence everything
   -v,  --verbose        verbose output
        --version        display version

Examples

$ dnsgrab -h hackerone.com
104.16.99.52:53

$ dnsgrab -i hosts.txt
104.16.62.39:53
104.17.206.78:53
104.18.69.91:53
104.18.110.82:53
104.18.107.24:53
104.17.70.206:53
104.16.99.52:53
104.18.70.91:53
35.166.157.178:53
35.166.157.178:53
104.17.73.206:53
10.13.22.219:53

Library

go get -u github.com/root4loot/dnsgrab

package main

import (
	"fmt"

	"github.com/root4loot/dnsgrab"
)

func main() {
	single()
	multiple()
	multipleStream()
}

func single() {
	fmt.Println("Running against single host")
	result := dnsgrab.Single("hackerone.com")
	fmt.Println("Query host", result.RequestedHost, "Resolver Address", result.ResolverAddress)
}

func multiple() {
	fmt.Println("Running against multiple hosts")
	results := dnsgrab.Multiple([]string{"hackerone.com", "bugcrowd.com", "intigriti.com"})
	for _, result := range results {
		fmt.Println("Query host", result.RequestedHost, "Resolver Address", result.ResolverAddress)
	}
}

func multipleStream() {
	fmt.Println("Running against multiple hosts (async)")
	targets := []string{"hackerone.com", "bugcasdasdrowd.com", "intigriti.com"}

	// initialize runner
	dnsgrab := dnsgrab.NewRunner()

	// OPTIONAL: set options
	// dnsgrab.Options.Resolvers = []string{""}
	// dnsgrab.Options.Concurrency = 0
	// dnsgrab.Options.Timeout = 0
	// dnsgrab.Options.Delay = 0
	// dnsgrab.Options.DelayJitter = 0
	dnsgrab.Options.Verbose = true

	// process results
	go func() {
		for result := range dnsgrab.Results {
			fmt.Println("Query host", result.RequestedHost, "Resolver Address", result.ResolverAddress)
		}
	}()

	// run dnsgrab against targets
	dnsgrab.MultipleStream(targets...)
}

---

Contributing

See CONTRIBUTING.md