RFC 7836, "Guidelines on the Cryptographic Algorithms to Accompany the Usage of Standards GOST R 34.10-2012 and GOST R 34.11-2012", March 2016

Errata ID: 6201
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Billy Brumley
Date Reported: 2020-06-03
Verifier Name: Adrian Farrel
Date Verified: 2020-07-01

Section 4.3.2 says:

where m and q are the parameters of an elliptic curve defined in the
GOST R 34.10-2012 [GOST3411-2012] standard (m is an elliptic curve
points group order, q is an order of a cyclic subgroup), P is a non-
zero point of the subgroup; P is defined by a protocol.

It should say:

where m and q are the parameters of an elliptic curve defined in the
GOST R 34.10-2012 [GOST3411-2012] standard (m is an elliptic curve
points group order, q is an order of a cyclic subgroup), P is a non-
zero point of the subgroup; P is defined by a specification of an elliptic
curve or by a protocol. Note that in most practical cases the private key
y is unknown so the point (y*P) is just a pair of coordinates, which
MUST be checked for satisfying the curve equation before calculating
the K value.

Notes:

The proposed text clarifies the P point specification ways and the need to check the public key of one side for belonging to the elliptic curve used by the opposite side.

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