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[mcr@sandelman.ottawa.on.ca: zero length binary strings]
I think that the BNF should be changed to
<decimal>:: "0" | <nzdigit> <digit>* ;
we DO want to allow for zero-length strings.
Thanks for catching this.
Cheers,
Ron Rivest
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Subject: zero length binary strings
Date: Wed, 22 Oct 1997 14:09:42 -0400
From: "Michael C. Richardson" <mcr@sandelman.ottawa.on.ca>
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It appears that there is no way to encode a zero-length binary
string.
Is that correct? This BNF says:
<byte-string>:: <bytes> | <display-type> <bytes> ;
<bytes>:: <decimal> ":" {binary byte string of that length} ;
<decimal>:: <nzddigit> <ddigit>* ;
<nzddigit>:: "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" ;
<ddigit>:: "0" | <nzddigit> ;
<display-type>:: "[" <bytes> "]" ;
So, the minimum length is '1'.
I ask for completeness, not because I want to encode a zero-length
string.
:!mcr!: | Network and security consulting/contract programming
Michael Richardson | I do IPsec policy code for SSH <http://www.ssh.fi/>
Personal: <A HREF="http://www.sandelman.ottawa.on.ca/People/Michael_Richardson/Bio.html">mcr@sandelman.ottawa.on.ca</A>. PGP key available.
Corporate: <A HREF="http://www.sandelman.ottawa.on.ca/SSW/">sales@sandelman.ottawa.on.ca</A>.
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