35 lines
1.0 KiB
Plaintext
35 lines
1.0 KiB
Plaintext
Bird's Hole Punching Protocol
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Hole punch - a mechanism to bypass a firewall
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Server - a third party which is not behind a firewall
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Client - anything contacting the server
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Magic - the four bytes 00 52 EB 11
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Address - an IPv4 address
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0 1 2 3 4 5 6 7 8 9
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+-------+-------+----+
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| Magic |Address|Port|
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+-------+-------+----+
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Relay Packet
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A client that expects to be the target of a hole punch
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must contact the server frequently, to keep a UDP
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"connection" open, so that the server may relay hole
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punching requests to them.
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A client makes a hole punching request to another client
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by sending a Relay Packet to the server. The server then
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sends another Relay Packet to the client described by the
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first packet. The second packet is filled with the source
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address and port of the first packet.
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Once a client receives a Relay Packet, this protocol's
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purpose is fulfilled and the client is aware that another
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client requests a hole punch.
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vim: noai
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