Internet-Draft Use of GOST 2012 Signatures in DNSSEC May 2023
Belyavskiy, et al. Expires 11 November 2023 [Page]
Network Working Group
Intended Status:
D. Belyavskiy
V. Dolmatov, Ed.
JSC "NPK Kryptonite"
B. Makarenko, Ed.
The Technical center of Internet, LLC

Use of GOST 2012 Signature Algorithms in DNSKEY and RRSIG Resource Records for DNSSEC


This document describes how to produce digital signatures and hash functions using the GOST R 34.10-2012 and GOST R 34.11-2012 algorithms for DNSKEY, RRSIG, and DS resource records, for use in the Domain Name System Security Extensions (DNSSEC).

Status of This Memo

This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.

Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet-Drafts is at

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This Internet-Draft will expire on 11 November 2023.

Table of Contents

1. Introduction

The Domain Name System (DNS) is the global hierarchically distributed database for Internet Naming. The DNS has been extended to use cryptographic keys and digital signatures for the verification of the authenticity and integrity of its data. RFC 4033 [RFC4033], RFC 4034 [RFC4034], and RFC 4035 [RFC4035] describe these DNS Security Extensions, called DNSSEC.

RFC 4034 describes how to store DNSKEY and RRSIG resource records, and specifies a list of cryptographic algorithms to use. This document extends that list with the signature and hash algorithms GOST R 34.10-2012 ([RFC7091]) and GOST R 34.11-2012 ([RFC6986]), and specifies how to store DNSKEY data and how to produce RRSIG resource records with these algorithms.

Algorithms GOST R 34.10-2012 and GOST R 34.11-2012 are national standards. Their cryptographic properties haven't been independently verified.

Familiarity with DNSSEC and with GOST signature and hash algorithms is assumed in this document.

1.1. Terminology

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

2. DNSKEY Resource Records

The format of the DNSKEY RR can be found in RFC 4034 [RFC4034].

GOST R 34.10-2012 public keys are stored with the algorithm number TBA1.

According to RFC 7091 [RFC7091], a public key is a point on the elliptic curve Q = (x,y). The wire representation of a public key MUST contain 64 octets, where the first 32 octets contain the little-endian representation of x and the second 32 octets contain the little-endian representation of y.

As RFC 6986 and RFC 7091 allows 2 variants of length of the output hash and signature and many variants of parameters of the digital signature, for the purpose of this document we use 256-bit variant of the digital signature algorithm, corresponding 256-bit variant of the digest algorithm. We select the parameters for the digital signature algorithm to be id-tc26-gost-3410-2012-256-paramSetA in RFC 7836 [RFC7836].

2.1. Using a Public Key with Existing Cryptographic Libraries

At the time of this writing, existing GOST-aware cryptographic libraries are capable of reading GOST public keys via a generic X.509 API if the key is encoded according to RFC 7091 [RFC7091], Section 2.3.2.

To make this encoding from the wire format of a GOST public key with the parameters used in this document, prepend the 64 octets of key data with the following 32-byte sequence:

0x30 0x5e 0x30 0x17 0x06 0x08 0x2a 0x85
0x03 0x07 0x01 0x01 0x01 0x01 0x30 0x0b
0x06 0x09 0x2a 0x85 0x03 0x07 0x01 0x02
0x01 0x01 0x01 0x03 0x43 0x00 0x04 0x40

These bytes provide the following ASN.1 structure suitable for parsing by cryptographic toolkits:

  0  62: SEQUENCE {
  2   1:   INTEGER 0
  5  23:   SEQUENCE {
  7   8:     OBJECT IDENTIFIER '1 2 643 7 1 1 1 1'
 17  11:     SEQUENCE {
 19   9:       OBJECT IDENTIFIER '1 2 643 7 1 2 1 1 1'
       :       }
       :     }
 30  32:   OCTET STRING

The OIDs in the structure above represent GOsudarstvennyy STandart (GOST) R 34.10-2012 public keys with 256 bits private key length algorithm with Parameter set A for Keyed-Hash Message Authentication Code (HMAC) transformation based on the GOsudarstvennyy STandart (GOST) R 34.11-2012 hash function with 256-bit output according to RFC 7836 [RFC7836] and RFC 9125 [RFC9125].

2.2. GOST DNSKEY RR Example

Given a private key with the following value:

Private-key-format: v1.2
Algorithm: 23 (ECC-GOST12)

The following DNSKEY RR stores a DNS zone key for example:

example.  600  IN  DNSKEY  256 3 23 (
    ) ;{id = 47355 (zsk), size = 512b}

Public key can be calculated from the private key using algorithm described in RFC 7091 [RFC7091].

[RFC Editor note: Algorithm numbers 23 and 5 are used as an example in this document, since the actual numbers have not yet been assigned.]

3. RRSIG Resource Records

The value of the signature field in the RRSIG RR follows RFC 7091 [RFC7091] and is calculated as follows. The values for the RDATA fields that precede the signature data are specified in RFC 4034 [RFC4034].

hash = GOSTR3411-2012(data)

where "data" is the wire format data of the resource record set that is signed, as specified in RFC 4034 [RFC4034].

The signature is calculated from the hash according to the GOST R 34.10-2012 standard, and its wire format is compatible with RFC 7091 [RFC7091].

3.1. RRSIG RR Example

Consider a given RRset consisting of one MX RR to be signed with the private key described in Section 2.2 of this document:

example.  600  IN  MX  10 mail.example.

Setting the inception date to 2022-10-06 12:32:30 UTC and the expiration date to 2022-11-03 12:32:30 UTC, the following signature RR will be valid:

example.  600 IN  RRSIG MX 23 1 600 20221103123230 (
                       20221006123230 47355 example.

The GOST R 34.10-2012 signature algorithm uses random (pseudorandom) integer k as described in Section 6.1 of RFC 7091 [RFC7091]. The following constant was used to replace k to provide a reproducible signature example.

k = 8BBD0CE7CAF3FC1C2503DF30D13ED5DB75EEC44060FA22FB7E29628407C1E34

This constant MUST NOT be used when computing GOST R 34.10-2012 signatures. It is provided only so the above signature example can be reproduced. The actual signature value will differ between signature calculations.

4. DS Resource Records

The GOST R 34.11-2012 digest algorithm is denoted in DS RRs by the digest type TBA2. The wire format of a digest value is compatible with RFC 6986 [RFC6986].

4.1. DS RR Example

For Key Signing Key (KSK):

example.  IN  DNSKEY  257 3 23 (
                       ) ;{id = 29468 (ksk), size = 512b}

The DS RR will be:

example.  IN  DS  29468 23 5 (

5. Operational Considerations

5.1. Key Sizes

The key size of GOST public keys conforming to this specification MUST be 512 bits according to RFC 7091 [RFC7091].

5.2. Signature Sizes

The size of a GOST signature conforming to this specification MUST be 512 bits according to RFC 7091 [RFC7091].

5.3. Digest Sizes

The size of a GOST digest conforming to this specification MUST be 256 bits according to RFC 6986 [RFC6986].

6. Implementation Considerations

The support of this cryptographic suite in DNSSEC-aware systems is OPTIONAL. According to RFC6840 [RFC6840], Section 5.2 systems that do not support these algorithms MUST ignore the RRSIG, DNSKEY and DS records created with them.

[(To be removed in RFC). To check the correctness of the implementation, authors recommend using OpenSSL 1.1.1 or 3.0.x series, a fork of ldns available at, and a reference implementation of GOST crypto algorithms available at]

7. IANA Considerations

This document updates the IANA registry "DNS Security Algorithm Numbers". The following entries have been added to the registry:

                                   Zone    Trans.
Value  Algorithm         Mnemonic  Signing Sec.  References
TBA1   GOST R 34.10-2012 ECC-GOST12    Y   *     RFC TBA

This document updates the IANA registry "Delegation Signer (DS) Resource Record (RR) Type Digest Algorithms" by adding an entry for the GOST R 34.11-2012 algorithm:

Value   Algorithm
TBA2    GOST R 34.11-2012

[RFC editor note: For the purpose of example computations, the following values were used: TBA1 = 23, TBA2 = 5. If the assigned values will differ, the example keys and signatures will have to be recalculated before the official publication of the RFC.]

8. Security Considerations

It is recommended to use a dual KSK algorithm signed zone until GOST-aware DNSSEC software become more widespread, unless GOST-only cryptography is required. Otherwise, GOST-signed zones may be considered unsigned by the DNSSEC software currently in use.

Currently, the cryptographic resistance of the GOST R 34.10-2012 digital signature algorithm is estimated as 2**128 operations of multiple elliptic curve point computations on prime modulus of order 2**256.

Currently, the cryptographic collision resistance of the GOST R 34.11-2012 hash algorithm is estimated as 2**128 operations of computations of a step hash function.

9. Acknowledgments

This document is a minor extension to RFC 4034 [RFC4034]. Also, we tried to follow the documents RFC 3110 [RFC3110], RFC 4509 [RFC4509], and RFC 5933 [RFC5933] for consistency. The authors of and contributors to these documents are gratefully acknowledged for their hard work.

The following people provided additional feedback, text, and valuable assistance: Alexander Venedyukhin, Michael StJohns, Valery Smyslov, Tim Wicinski, Stephane Bortzmeyer.

10. References

10.1. Normative References

Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <>.
Eastlake 3rd, D., "RSA/SHA-1 SIGs and RSA KEYs in the Domain Name System (DNS)", RFC 3110, DOI 10.17487/RFC3110, , <>.
Arends, R., Austein, R., Larson, M., Massey, D., and S. Rose, "DNS Security Introduction and Requirements", RFC 4033, DOI 10.17487/RFC4033, , <>.
Arends, R., Austein, R., Larson, M., Massey, D., and S. Rose, "Resource Records for the DNS Security Extensions", RFC 4034, DOI 10.17487/RFC4034, , <>.
Arends, R., Austein, R., Larson, M., Massey, D., and S. Rose, "Protocol Modifications for the DNS Security Extensions", RFC 4035, DOI 10.17487/RFC4035, , <>.
Weiler, S., Ed. and D. Blacka, Ed., "Clarifications and Implementation Notes for DNS Security (DNSSEC)", RFC 6840, DOI 10.17487/RFC6840, , <>.
Dolmatov, V., Ed. and A. Degtyarev, "GOST R 34.11-2012: Hash Function", RFC 6986, DOI 10.17487/RFC6986, , <>.
Dolmatov, V., Ed. and A. Degtyarev, "GOST R 34.10-2012: Digital Signature Algorithm", RFC 7091, DOI 10.17487/RFC7091, , <>.
Smyshlyaev, S., Ed., Alekseev, E., Oshkin, I., Popov, V., Leontiev, S., Podobaev, V., and D. Belyavsky, "Guidelines on the Cryptographic Algorithms to Accompany the Usage of Standards GOST R 34.10-2012 and GOST R 34.11-2012", RFC 7836, DOI 10.17487/RFC7836, , <>.
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <>.

10.2. Informative References

Hardaker, W., "Use of SHA-256 in DNSSEC Delegation Signer (DS) Resource Records (RRs)", RFC 4509, DOI 10.17487/RFC4509, , <>.
Dolmatov, V., Ed., Chuprina, A., and I. Ustinov, "Use of GOST Signature Algorithms in DNSKEY and RRSIG Resource Records for DNSSEC", RFC 5933, DOI 10.17487/RFC5933, , <>.
Farrel, A., Drake, J., Rosen, E., Patel, K., and L. Jalil, "Gateway Auto-Discovery and Route Advertisement for Site Interconnection Using Segment Routing", RFC 9125, DOI 10.17487/RFC9125, , <>.

Authors' Addresses

Dmitry Belyavskiy
8 marta st
Russian Federation
Vasily Dolmatov (editor)
JSC "NPK Kryptonite"
Spartakovskaya sq., 14, bld 2, JSC "NPK Kryptonite"
Russian Federation
Boris Makarenko (editor)
The Technical center of Internet, LLC
8 marta str., 1, bld 12
Russian Federation