March 31, 2021

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jvns/dnspeep

jvns/dnspeep

spy on the DNS queries your computer is making

repo name jvns/dnspeep
repo link https://github.com/jvns/dnspeep
homepage
language Rust
size (curr.) 20 kB
stars (curr.) 658
created 2021-03-28
license MIT License

dnspeep

dnspeep lets you spy on the DNS queries your computer is making.

Here’s some example output:

$ sudo dnspeep
query name                           server IP       response
A     incoming.telemetry.mozilla.org 192.168.1.1     CNAME: telemetry-incoming.r53-2.services.mozilla.com, CNAME: pipeline-incoming-prod-elb-149169523.us-west-2.elb.amazonaws.com, A: 52.39.144.189, A: 54.191.136.131, A: 34.215.151.143, A: 54.149.208.57, A: 44.226.235.191, A: 52.10.174.113, A: 35.160.138.173, A: 44.238.190.78
AAAA  incoming.telemetry.mozilla.org 192.168.1.1     CNAME: telemetry-incoming.r53-2.services.mozilla.com, CNAME: pipeline-incoming-prod-elb-149169523.us-west-2.elb.amazonaws.com
A     www.google.com                 192.168.1.1     A: 172.217.13.132
AAAA  www.google.com                 192.168.1.1     AAAA: 2607:f8b0:4020:807::2004
A     www.neopets.com                192.168.1.1     CNAME: r9c3n8d2.stackpathcdn.com, A: 151.139.128.11
AAAA  www.neopets.com                192.168.1.1     CNAME: r9c3n8d2.stackpathcdn.com

How to install

You can install dnspeep using the different methods below.

Installing the binary release

  1. Download recent release of dnspeep from the GitHub releases page
  2. Unpack it
  3. Put the dnspeep binary in your PATH (for example in /usr/local/bin)

Compile and installing from source

  1. Download recent source release of dnspeep from the GitHub releases page or git clone this repository.
  2. Unpack it
  3. Run cargo build --release
  4. Change to the “target/release” directory there.
  5. Put the dnspeep binary in your PATH (for example in /usr/local/bin)

Installing from a Linux package manager

  • If you are using Arch Linux, then you can install dnspeep from the AUR.

How it works

It uses libpcap to capture packets on port 53, and then matches up DNS request and response packets so that it can show the request and response together on the same line.

It also tracks DNS queries which didn’t get a response within 1 second and prints them out with the response <no response>.

Limitations

  • Only supports the DNS query types supported by the dns_parser crate (here’s a list)
  • Doesn’t support TCP DNS queries, only UDP
  • It can’t show DNS-over-HTTPS queries (because it would need to MITM the HTTPS connection)
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