Answer NXDOMAIN for _.xxx.yyy.top.domain#120
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Closes #119 |
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When a DNS query name is too long, it is split into multiple domain components. However, recursive DNS servers that implement QNAME minimization may query each subdomain individually without revealing the full name. As part of this behavior, they often send a preliminary query for a hostname like "_" before attempting to resolve the full name. If this query is not handled correctly, it can lead to timeouts and failed connections. The most effective way to avoid this is to respond with an NXDOMAIN for such queries. Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>
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When a DNS query name is too long, it is split into multiple domain components. However, recursive DNS servers that implement QNAME minimization may query each subdomain individually without revealing the full name. As part of this behavior, they often send a preliminary query for a hostname like "_" before attempting to resolve the full name. If this query is not handled correctly, it can lead to timeouts and failed connections. The most effective way to avoid this is to respond with an NXDOMAIN for such queries.