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Re: [Json] Bug in RFC7493 (I-JSON)?

Tim Bray <tbray@textuality.com> Sun, 06 May 2018 06:34 UTC

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From: Tim Bray <tbray@textuality.com>
Date: Sat, 05 May 2018 23:34:05 -0700
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To: Anders Rundgren <anders.rundgren.net@gmail.com>
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Subject: Re: [Json] Bug in RFC7493 (I-JSON)?
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So… the spec underpromises and overdelivers :)

Seriously, I wonder if this behavior is portable across IEEE 754
implementations.

On Sat, May 5, 2018 at 11:21 PM, Anders Rundgren <
anders.rundgren.net@gmail.com> wrote:

> During testing of the JSON canonicalizer [1,2] I tried with an integer
> just above the specified limit (2**53) + 1 and to my surprise it didn't
> fail.
> A short run with an IEEE-754/ES6 debugger seemed to confirm that +-2**53
> is the actual limit for integers.
>
> Input floating point: 9007199254740991
> Output floating point: 9007199254740991
> Hex value: 433fffffffffffff
> Binary value: 0 10000110011 111111111111111111111111111111
> 1111111111111111111111
>
> Input floating point: 9007199254740992
> Output floating point: 9007199254740992
> Hex value: 4340000000000000
> Binary value: 0 10000110100 000000000000000000000000000000
> 0000000000000000000000
>
> Anders
>
> 1] https://github.com/cyberphone/json-canonicalization#json-can
> onicalization
> 2] https://cyberphone.github.io/doc/security/draft-rundgren-jso
> n-canonicalization-scheme.html
>
>
> _______________________________________________
> json mailing list
> json@ietf.org
> https://www.ietf.org/mailman/listinfo/json
>



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