[TLS] Length of a variable-length vector: zero-length case

=JeffH <Jeff.Hodges@KingsMountain.com> Fri, 22 January 2016 15:50 UTC

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From: =JeffH <Jeff.Hodges@KingsMountain.com>
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Subject: [TLS] Length of a variable-length vector: zero-length case
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wrt https://tools.ietf.org/html/draft-ietf-tls-tls13-11#section-4.3

if we have..

   opaque foo<0..2^16-1>;

..with a floor length of zero, thus with an instantiation of foo of zero 
length, we actually will have in terms of encoded bytes on the wire (in hex)..

   00 00

..where this is the 2-byte length field, with length value zero, and a
zero-length (ie, absent, empty) vector content, correct ?

thanks,

=JeffH