Error Codes & Status Mapping

DoHflare relies on standard HTTP status codes combined with custom headers (X-DOHFLARE-Code) for precise debugging without breaking the DNS payload format.

HTTP Status	Internal Code	Description
200 OK	N/A	Successful resolution (Cache HIT or MISS).
400 Bad Request	N/A	Missing dns parameter, invalid Base64URL, or malformed DNS query.
405 Method Not Allowed	N/A	Request method is not GET, POST, or OPTIONS.
413 Payload Too Large	N/A	POST body exceeds MAX_POST_BODY_BYTES.
415 Unsupported Media Type	N/A	Missing or invalid Content-Type header in POST request.
502 Bad Gateway	UPSTREAM_ERR	Upstream resolvers are unreachable or returned an invalid response.
500 Internal Server Error	INTERNAL_FATAL	Unhandled exception during payload parsing or cache writing.

Internal Parsing Errors (Captured in logs):

• OOB_READ: Attempted to read out-of-bounds memory in the ArrayBuffer.
• MALFORMED_LOOP: Detected an infinite pointer loop in the DNS name compression scheme.
• PAYLOAD_TOO_LARGE: Upstream response exceeded MAX_CACHEABLE_BYTES.