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30 lines
734 B
Markdown
30 lines
734 B
Markdown
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# bufsize
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## Name
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*bufsize* - sizes EDNS0 buffer size to prevent IP fragmentation.
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## Description
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*bufsize* limits a requester's UDP payload size.
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It prevents IP fragmentation so that to deal with DNS vulnerability.
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## Syntax
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```txt
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bufsize [SIZE]
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```
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**[SIZE]** is an int value for setting the buffer size.
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The default value is 512, and the value must be within 512 - 4096.
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Only one argument is acceptable, and it covers both IPv4 and IPv6.
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## Examples
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```corefile
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. {
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bufsize 512
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forward . 172.31.0.10
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log
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}
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```
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If you run a resolver on 172.31.0.10, the buffer size of incoming query on the resolver will be set to 512 bytes.
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## Considerations
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For now, if a client does not use EDNS, this plugin adds OPT RR.
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