[Cfrg] rfc7539 implementation

"Grigory Marshalko" <marshalko_gb@tc26.ru> Mon, 08 February 2016 18:23 UTC

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Subject: [Cfrg] rfc7539 implementation
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Hello all,

In rfc7539 in section 2.5 it is written that

	"r" MAY be constant, but needs to be modified as follows before being used: ("r" is treated as a 16-octet little-endian number):
and

	 The "s" should be unpredictable, but it is perfectly acceptable to generate both "r" and "s" uniquely each time. 
Does this mean that we may either use algorithm from 2.6 to generate both r and s, or, say, for better performance generate only s, and r may be constant during session?

Regards,
Grigory Marshalko,
expert,
Technical committee for standardisation "Cryptography and security mechanisms" (ТC 26)
www.tc26.ru