XSN Seeder

xsn-seeder is a crawler for the XSN Core network, which exposes a list of reliable nodes via a built-in DNS server, or instead just generates that list to push to a remote CloudFlare server.

Features:

• CloudFlare DNS integration
• regularly revisits known nodes to check their availability
• bans nodes after enough failures, or bad behaviour
• accepts nodes down to v0.3.19 to request new IP addresses from, but only reports good post-v0.3.24 nodes.
• keeps statistics over (exponential) windows of 2 hours, 8 hours, 1 day and 1 week, to base decisions on.
• very low memory (a few tens of megabytes) and cpu requirements.
• crawlers run in parallel (by default 24 threads simultaneously).

REQUIREMENTS

$ sudo apt-get install build-essential libboost-all-dev libssl-dev

USAGE: LOCAL DNS SERVER MODE

Assuming you want to run a dns seed on dnsseed.example.com, you will need an authorative NS record in example.com's domain record, pointing to for example vps.example.com:

$ dig -t NS dnsseed.example.com

;; ANSWER SECTION dnsseed.example.com. 86400 IN NS vps.example.com.

On the system vps.example.com, you can now run dnsseed:

./dnsseed -h dnsseed.example.com -n vps.example.com

If you want the DNS server to report SOA records, please provide an e-mail address (with the @ part replaced by .) using -m.

USAGE: CLOUDFLARE API MODE

Have the seeder above running all the time, but with no NS record:

./dnsseed -h {host_ip}

Fill in CloudFlare API config (see ./cf-uploader/README.md) and have the CloudFlare upload run on a cron job:

Create a python virtual env:

virtualenv ./venv

Set up a crontab entry to call cf-uploader every 30 minutes:

$ crontab -e

In the crontab editor, add the lines below:

* * * * * cd {xsn_seeder_path}/cf-uploader && ./venv/bin/python seeder.py >/dev/null 2>&1

COMPILING

Compiling will require boost and ssl. On debian systems, these are provided by libboost-dev and libssl-dev respectively.

$ make

This will produce the dnsseed binary.

RUNNING AS NON-ROOT

Typically, you'll need root privileges to listen to port 53 (name service).

One solution is using an iptables rule (Linux only) to redirect it to a non-privileged port:

$ iptables -t nat -A PREROUTING -p udp --dport 53 -j REDIRECT --to-port 5353

If properly configured, this will allow you to run dnsseed in userspace, using the -p 5353 option.