CIRCL Passive DNS is accessible via a REST API and the output format is in JSON following Passive DNS - Common Output Format.
The REST API is accessible via the following URL
https://www.circl.lu/pdns/query/<queryvalue>
Query values can be any records like IP addresses, hostnames or domain names (please note that CIDR block queries are not supported):
https://www.circl.lu/pdns/query/www.circl.lu
and a sample JSON output:
1{"count": 20426, "time_first": 1298398417, "rrtype": "A", "rrname": "www.circl.lu", "rdata": "194.154.205.24", "time_last": 1299264077} {"count": 202990, "time_first": 1298398002, "rrtype": "CNAME", "rrname": "www.circl.lu", "rdata": "cpa.circl.lu", "time_last": 1408612615}
Access to CIRCL Passive DNS is only allowed to trusted partners in Luxembourg and abroad. Contact us if you would like access. Include your affiliation and the foreseen use of the Passive DNS data.
We developed a Python library called PyPDNS to query any Passive DNS implementation following the Passive DNS - Common Output Format.
PassiveDNS::Client is a rubygem developed by Chris Lee who includes access to different passive DNS services including CIRCL.
Scala library is a Scala implementation developed by Jason Jones.