dig.js

Create and capture DNS and mDNS query and response packets to disk as binary and/or JSON. Options are similar to the Unix `dig` command.

Usage no npm install needed!

<script type="module">
  import digJs from 'https://cdn.skypack.dev/dig.js';
</script>

README

dig.js

| dns-suite | dig.js | mdig.js | digd.js | Sponsored by ppl.

Create and capture DNS and mDNS query and response packets to disk as binary and/or JSON. Options are similar to the Unix dig command. Supports dns0x20 security checking.

Install

with git

# Install the latest of v1.x
npm install -g 'git+https://git.coolaj86.com/coolaj86/dig.js.git#v1'

# Install exactly v1.0.0
npm install -g 'git+https://git.coolaj86.com/coolaj86/dig.js.git#v1.0.0'

without git

Don't have git? Well, you can also bow down to the gods of the centralized, monopolized, concentrated, dictatornet (as we like to call it here at ppl Labs), if that's how you roll:

npm install -g dig.js

Usage

dig.js [TYPE] <domainname>

Example:

dig.js coolaj86.com

mDNS Browser Example

This is pretty much an mDNS browser

dig.js --mdns _services._dns-sd._udp.local

Really the --mdns option is just an alias for setting all of these options as the default:

dig.js -p 5353 @224.0.0.251 PTR _services._dns-sd._udp.local +time=3

Moar Examples

dig.js A coolaj86.com

dig.js @8.8.8.8 A coolaj86.com

Options

--output <path/to/file>     write query and response(s) to disk with this path prefix (ex: ./samples/dns)

--mdns                      Use mDNS port and nameserver address, and listen for multiple packets

-t <type> (superfluous)     A, CNAME, MX, etc. Also supports -t type<decimal> for "unsupported" types. default ANY (mdns default: PTR)
-c <class>                  default IN
-p <port>                   default 53 (mdns default: 5353) (listener is random for DNS and 5353 for mDNS)
-q <query> (superfluous)    required (ex: coolaj86.com)
--nameserver <ns>           alias of @<nameserver>
--timeout <ms>              alias of +time=<seconds>, but in milliseconds

@<nameserver>               specify the nameserver to use for DNS resolution (defaults to system defaults)
+time=<seconds>             Sets the timeout for a query in seconds.
+norecurse                  Set `rd` flag to 0. Do not request recursion
+aaonly                     Set `aa` flag to 1.

--norecase         					Disable dns0x20 security checking (mixed casing). See https://dyn.com/blog/use-of-bit-0x20-in-dns-labels/
--recase           					Print the dns0x20 casing as-is rather than converting it back to lowercase. This is the default when explicitly using mixed case.

--debug                     verbose output

Security Concerns

The 16-bit id of the query must match that of the response.

Extra entropy is added by using dns0x20, the de facto standard for RanDOmCASiNg on the query which must be matched in the response.