Re: [Cfrg] Point format endian (was: Adoption of draft-ladd-spake2 as a RG document)
"D. J. Bernstein" <djb@cr.yp.to> Sun, 25 January 2015 08:30 UTC
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From: "D. J. Bernstein" <djb@cr.yp.to>
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Subject: Re: [Cfrg] Point format endian (was: Adoption of draft-ladd-spake2 as a RG document)
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> a long-standing tradition of the on-the-wire format Just to make sure that I understand, after reviewing a ton of tcpdump output: You're referring to the HTTP tradition of variable-length ASCII decimal encodings for integers on the wire (cache times, data lengths, version numbers, etc.)? Does this mean that IETF pushed this HTTP tradition into AES-GCM's internal integer encodings before deploying AES-GCM, and plans to do the same for other cryptographic systems? > better looking and more maintainable code You're absolutely right: being able to reuse existing variable-length ASCII decimal integer encoders and decoders has always been a critical part, I daresay the most important part, of implementing, reading, auditing, and maintaining cryptographic software. RFC 1321 (MD5) got this totally wrong---the integers are _backwards_ and _non-decimal_ and _non-ASCII_---and we all know what happened to MD5 as a result. Now that you've reminded me of what really matters for cryptographic code complexity and security, I would love to put together an ASCII decimal version of Curve25519, but I have to admit that I'm not _completely_ clear on the details of the HTTP tradition that you're talking about. For example, are leading zeros allowed? This would allow simpler integer encoding for some embedded systems, but it would cause trouble for existing parsers that switch to octal for a leading 0, such as base-0 strtol(). Also, can the integers exceed 2147483647? ---Dan
- [Cfrg] Adoption of draft-ladd-spake2 as a RG docu… Alexey Melnikov
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Rene Struik
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Watson Ladd
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Watson Ladd
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … David Leon Gil
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Alexey Melnikov
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Yoav Nir
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Alexey Melnikov
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Stephen Farrell
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Michael Hamburg
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Dan Harkins
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Watson Ladd
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Dan Harkins
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Derek Atkins
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Dan Harkins
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Andy Lutomirski
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Paul Lambert
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Watson Ladd
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Alexey Melnikov
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Alexey Melnikov
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Dan Harkins
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Paul Lambert
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Tom Yu
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Andy Lutomirski
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Dearlove, Christopher (UK)
- Re: [Cfrg] Point format endian (was: Adoption of … Alyssa Rowan
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Alexey Melnikov
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Adam Langley
- Re: [Cfrg] Adoption of draft-ladd-spake2 as a RG … Paul Lambert
- [Cfrg] On the topic of the SPAKE2 draft Paul Lambert
- Re: [Cfrg] Point format endian (was: Adoption of … Dan Harkins
- Re: [Cfrg] Point format endian (was: Adoption of … Watson Ladd
- Re: [Cfrg] Point format endian (was: Adoption of … Salz, Rich
- Re: [Cfrg] Point format endian (was: Adoption of … Dan Harkins
- Re: [Cfrg] Point format endian (was: Adoption of … Watson Ladd
- Re: [Cfrg] Point format endian (was: Adoption of … D. J. Bernstein
- Re: [Cfrg] Point format endian (was: Adoption of … Dan Harkins
- Re: [Cfrg] Point format endian (was: Adoption of … Mike Hamburg
- Re: [Cfrg] Point format endian (was: Adoption of … Salz, Rich
- Re: [Cfrg] Point format endian (was: Adoption of … Watson Ladd
- Re: [Cfrg] Point format endian (was: Adoption of … Andrey Jivsov
- Re: [Cfrg] Point format endian Alyssa Rowan
- Re: [Cfrg] Point format endian (was: Adoption of … Salz, Rich
- Re: [Cfrg] Point format endian (was: Adoption of … Damien Miller
- Re: [Cfrg] Point format endian (was: Adoption of … Dan Harkins
- Re: [Cfrg] Point format endian (was: Adoption of … Mike Hamburg
- Re: [Cfrg] Point format endian (was: Adoption of … Watson Ladd
- Re: [Cfrg] Point format endian (was: Adoption of … Yoav Nir
- Re: [Cfrg] Point format endian Michael Clark