A Go daemon to bridge Namecoin to DNS. The daemon acts as an authoritative nameserver and queries a Namecoin daemon over JSON-RPC in order to obtain zone data.
The daemon can optionally sign zones with DNSSEC and supports the use of DS records in Namecoin. It works best when used by Unbound or another recursive resolver, or as an authoritative nameserver for a stub zone.
Using ncdns to provide a suffix
The daemon acts as an authoritative nameserver for any name containing a 'bit' label. For example, all of the following queries return the same records:
This enables the easy use of suffixes. (Note that this will cause a different hostname to be transmitted for protocols like HTTP, and server configuration may need to be modified to enable this. In some cases there may be no simple solution to enabling arbitrary suffix use with a given piece of server software, in which known suffixes can be configured; patches for such software would be desirable.)
Using ncdns with a recursive resolver
Of course the daemon can also be used simply as an authoritative nameserver for bit. directly. One way to do this is to run a recursive resolver (such as Unbound) and configure it to serve the zone as a 'stub zone'. Here is an example unbound configuration:
server: do-not-query-localhost: no stub-zone: name: bit. stub-addr: 127.0.0.1@1153
If you don't want to use DNSSEC, also add:
server: domain-insecure: bit.
If you do want to use DNSSEC, see the instructions below.
Note how you can specify a port other than 53. This allows you to run both Unbound and ncdns on the same machine. Alternately, you could add an additional loopback IP address (127.0.0.2) and bind ncdns to that. This is useful if your recursive resolver doesn't support a port number other than 53.
To use DNSSEC, generate keys with
ldns-keygen. You will need
to generate a key-signing key and a zone-signing key:
# Generate KSK. $ dnssec-keygen -a RSASHA256 -3 -b 2048 -f KSK bit # Generate ZSK. $ dnssec-keygen -a RSASHA256 -3 -b 2048 bit
Each of these commands will generate a pair of files, a
.key file and a
.private file. Make a note of which is the KSK and which is the ZSK. If you
forget, check the comments inside the .key file. (If there are no comments for
some reason, a KSK usually contains the string
DNSKEY 256 and a ZSK
(You could substitute something else for
bit as ncdns doesn't care. However
if you want to use the key as a trust anchor with a recursive resolver such as
unbound, you should specify
If using Unbound as a recursive resolver, you should add the KSK's public key file as a trust anchor to unbound like so:
server: trust-anchor-file: "/etc/unbound/keys/bit.key"
bit.key should be the file containing the KSK DNSKEY (or DS) which ncdns is
configured to use.
Ensure you have the Go tools installed.
If using Linux, ensure you have the
libcapdevelopment headers installed. (Most distributions will have a package called
Option A: Using Go build commands (works on any platform with Bash):
Ensure you have the GOPATH environment variable set. (For those not familar with Go, setting it to the path to an empty directory will suffice. The directory will be filled with build files.)
go get -d -t -u github.com/namecoin/ncdns/.... The ncdns source code will be retrieved automatically.
go generate github.com/namecoin/ncdns/.... Some source code will be generated.
go get -t github.com/namecoin/ncdns/.... ncdns will be built. The binaries will be at $GOPATH/bin/ncdns.
Option B: Using Makefile (non-Windows platforms):
make. The source repository will be retrieved via
ncdns can be run as a Windows service; see the output of
ncdns uses a configuration file which is looked for at
(relative to the executable path) and
/etc/ncdns/ncdns.conf. You can override
this and all options on the command line. An annotated example configuration
ncdns.conf.example is available in doc.
You will need to setup a
namecoin-qt or compatible Namecoin node
and enable the JSON-RPC interface. You will then need to provide
the address of this interface and any necessary username and password via the
If you only want to resolve .bit names yourself, here is a suggested setup on Linux:
namecoin-qt) and set it to start automatically at boot or login. Set up the JSON-RPC interface and make sure it works by making a test query:
namecoind name_show d/example.
Write a ncdns configuration file and set ncdns up to start at boot. Since Unbound will tie up port 53, set a different port (ideally one >=1024, so it needn't be run as root.) Test that ncdns works by trying to resolve a
.bitdomain. If you want to use DNSSEC, generate keys as shown above and configure ncdns appropriately.
Install and setup the Unbound recursive resolver on your system. On most systems, the recommended way to install Unbound is to install DNSSEC Trigger, which installs and configures Unbound automatically.
If you wish to use DNSSEC, add the ncdns DNSKEY to Unbound as a trust anchor as shown above. See above for configuration suggestions.
/etc/resolv.confto point to the Unbound resolver at 127.0.0.1. (If this file is generated automatically via DHCP or similar, you may find these changes keep getting wiped out. Either reconfigure whatever keeps overwriting it to stop doing so, or, as a stopgap measure, make the file immutable using
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