[MMUSIC] RFC 5245: ice-ufrags of length 256 vs stun maximum username length of 512 bytes

Philipp Hancke <fippo@goodadvice.pages.de> Wed, 14 August 2013 06:54 UTC

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Date: Wed, 14 Aug 2013 08:54:23 +0200
From: Philipp Hancke <fippo@goodadvice.pages.de>
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Subject: [MMUSIC] RFC 5245: ice-ufrags of length 256 vs stun maximum username length of 512 bytes
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It seems that there is a minor inconsistency between the maximum 
username length in STUN and the way ice-ufrag is defined...

5245 allows ufrags of up to 256 characters:
	-- http://tools.ietf.org/html/rfc5245#section-15.4

The STUN username is formed as RFRAG:LFRAG

If both sides use 256 characters for their ufrags this would result in a 
513 byte STUN username. However, 5389 says the username has to be "less 
than 513 bytes".
	-- http://tools.ietf.org/html/rfc5389#section-15.3

Off by one?

For ice-pwd this isn't a problem, right?