checker-delegation

DNS delegation checker for happyDomain.

Audits the delegation of a zone: NS consistency between parent and child, glue correctness, DS / DNSKEY hand-off, TCP reachability, SOA serial drift, and authoritativeness of each delegated server. Applies to services of type abstract.Delegation.

Usage

Standalone HTTP server

# Build and run
make
./checker-delegation -listen :8080

The server exposes:

• GET /health, health check
• POST /collect, collect delegation observations (happyDomain external checker protocol)

Docker

make docker
docker run -p 8080:8080 happydomain/checker-delegation

happyDomain plugin

make plugin
# produces checker-delegation.so, loadable by happyDomain as a Go plugin

The plugin exposes a NewCheckerPlugin symbol returning the checker definition and observation provider, which happyDomain registers in its global registries at load time.

Versioning

The binary, plugin, and Docker image embed a version string overridable at build time:

make CHECKER_VERSION=1.2.3
make plugin CHECKER_VERSION=1.2.3
make docker CHECKER_VERSION=1.2.3

happyDomain remote endpoint

Set the endpoint admin option for the delegation checker to the URL of the running checker-delegation server (e.g., http://checker-delegation:8080). happyDomain will delegate observation collection to this endpoint.

Deployment

The /collect endpoint has no built-in authentication and will issue DNS queries to whatever name servers (and glue addresses) the parent zone advertises for the target. It is meant to run on a trusted network, reachable only by the happyDomain instance that drives it. Restrict access via a reverse proxy with authentication, a network ACL, or by binding the listener to a private interface; do not expose it directly to the public internet.

Options

Option	Type	Default	Description
requireDS	bool	false	When enabled, missing DS records at the parent are treated as critical (otherwise informational).
requireTCP	bool	true	When enabled, name servers that fail to answer over TCP are reported as critical (otherwise warning).
minNameServers	uint	2	Below this count, the delegation is reported as a warning (RFC 1034 recommends at least 2).
allowGlueMismatch	bool	false	When disabled, glue/address mismatches between parent and child are reported as critical.

Protocol

POST /collect

Request:

{
  "key": "delegation",
  "target": {"userId": "...", "domainId": "..."},
  "options": {
    "domain_name": "example.com.",
    "subdomain": "www",
    "service": { "_svctype": "abstract.Delegation", "Service": { "ns": [...], "ds": [...] } }
  }
}

Response:

{
  "data": {
    "delegated_fqdn": "www.example.com.",
    "parent_zone": "example.com.",
    "parent_ns": ["a.iana-servers.net.", "b.iana-servers.net."],
    "advertised_ns": ["ns1.example.net.", "ns2.example.net."],
    "advertised_glue": {},
    "parent_ds": [],
    "child_serials": {"ns1.example.net.:53": 2026042401},
    "findings": [
      {
        "code": "delegation_ns_mismatch",
        "severity": "crit",
        "message": "NS RRset at parent does not match declared service: missing=[ns3.example.net] extra=[]",
        "server": "a.iana-servers.net.:53"
      }
    ]
  }
}

Findings carry a stable code (e.g. delegation_lame, delegation_missing_glue, delegation_ds_mismatch, delegation_soa_serial_drift, delegation_dnskey_no_match, …) so that downstream rules can match on them deterministically.

License

This project is licensed under the MIT License (see LICENSE), in line with the rest of the happyDomain checker ecosystem.

The third-party Apache-2.0 attributions for checker-sdk-go are recorded in NOTICE and must accompany any binary or source redistribution of this project.