GOST Cipher Suites for Transport Layer Security (TLS) Protocol Version 1.3
draft-smyshlyaev-tls13-gost-suites-04
Network Working Group S. Smyshlyaev, Ed.
Internet-Draft E. Alekseev
Intended status: Informational E. Griboedova
Expires: December 12, 2021 A. Babueva
CryptoPro
June 10, 2021
GOST Cipher Suites for Transport Layer Security (TLS) Protocol Version
1.3
draft-smyshlyaev-tls13-gost-suites-04
Abstract
The purpose of this document is to make the Russian cryptographic
standards available to the Internet community for their
implementation in the Transport Layer Security (TLS) Protocol Version
1.3.
This specification defines four new cipher suites and seven new
signature schemes based on GOST R 34.12-2015, GOST R 34.11-2012 and
GOST R 34.10-2012 algorithms. This document does not imply IETF
endorsement of the cipher suites.
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 https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on December 12, 2021.
Copyright Notice
Copyright (c) 2021 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
Smyshlyaev, et al. Expires December 12, 2021 [Page 1]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
(https://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Conventions Used in This Document . . . . . . . . . . . . . . 4
3. Basic Terms and Definitions . . . . . . . . . . . . . . . . . 4
4. Cipher Suite Definition . . . . . . . . . . . . . . . . . . . 6
4.1. Record Protection Algorithm . . . . . . . . . . . . . . . 6
4.1.1. AEAD Algorithm . . . . . . . . . . . . . . . . . . . 7
4.1.2. TLSTREE . . . . . . . . . . . . . . . . . . . . . . . 9
4.1.3. SNMAX parameter . . . . . . . . . . . . . . . . . . . 10
4.2. Hash Algorithm . . . . . . . . . . . . . . . . . . . . . 10
5. Signature Scheme Definition . . . . . . . . . . . . . . . . . 11
5.1. Signature Algorithm . . . . . . . . . . . . . . . . . . . 11
5.2. Elliptic Curve . . . . . . . . . . . . . . . . . . . . . 12
5.3. SIGN function . . . . . . . . . . . . . . . . . . . . . . 13
6. Key Exchange and Authentication . . . . . . . . . . . . . . . 13
6.1. Key Exchange . . . . . . . . . . . . . . . . . . . . . . 14
6.1.1. ECDHE Shared Secret Calculation . . . . . . . . . . . 14
6.1.1.1. ECDHE Shared Secret Calculation on Client Side . 14
6.1.1.2. ECDHE Shared Secret Calculation on Server Side . 16
6.1.1.3. Public ephemeral key representation . . . . . . . 17
6.1.2. Values for the TLS Supported Groups Registry . . . . 17
6.2. Authentication . . . . . . . . . . . . . . . . . . . . . 18
6.3. Handshake Messages . . . . . . . . . . . . . . . . . . . 19
6.3.1. Hello Messages . . . . . . . . . . . . . . . . . . . 19
6.3.2. CertificateRequest . . . . . . . . . . . . . . . . . 20
6.3.3. Certificate . . . . . . . . . . . . . . . . . . . . . 20
6.3.4. CertificateVerify . . . . . . . . . . . . . . . . . . 21
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21
8. Historical considerations . . . . . . . . . . . . . . . . . . 23
9. Security Considerations . . . . . . . . . . . . . . . . . . . 23
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 24
10.1. Normative References . . . . . . . . . . . . . . . . . . 24
10.2. Informative References . . . . . . . . . . . . . . . . . 25
Appendix A. Test Examples . . . . . . . . . . . . . . . . . . . 26
Appendix B. Contributors . . . . . . . . . . . . . . . . . . . . 26
Appendix C. Acknowledgments . . . . . . . . . . . . . . . . . . 26
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 26
Smyshlyaev, et al. Expires December 12, 2021 [Page 2]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
1. Introduction
This document defines four new cipher suites (the TLS13_GOST cipher
suites) and seven new signature schemes (the TLS13_GOST signature
schemes) for the Transport Layer Security (TLS) Protocol Version 1.3,
that are based on Russian cryptographic standards GOST R 34.12-2015
[GOST3412-2015] (the English version can be found in [RFC7801]), GOST
R 34.11-2012 [GOST3411-2012] (the English version can be found in
[RFC6986]) and GOST R 34.10-2012 [GOST3410-2012] (the English version
can be found in [RFC7091]).
The TLS13_GOST cipher suites (see Section 4) have the following
values:
TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_L = {0xC1, 0x03};
TLS_GOSTR341112_256_WITH_MAGMA_MGM_L = {0xC1, 0x04};
TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_S = {0xC1, 0x05};
TLS_GOSTR341112_256_WITH_MAGMA_MGM_S = {0xC1, 0x06}.
Each TLS13_GOST cipher suite specifies a pair (record protection
algorithm, hash algorithm) such that:
o The record protection algorithm is the AEAD algorithm (see
Section 4.1.1) based on the GOST R 34.12-2015 block cipher
[RFC7801] in the Multilinear Galois Mode (MGM) [DraftMGM] and the
external re-keying approach (see [RFC8645]) intended for
increasing the lifetime of symmetric keys used to protect records.
o The hash algorithm is the GOST R 34.11-2012 algorithm [RFC6986].
Note: The TLS13_GOST cipher suites are divided into two types
(depending on the key lifetime limitations, see Section 4.1.2 and
Section 4.1.3): the "_S" (strong) cipher suites and the "_L" (light)
cipher suites.
The TLS13_GOST signature schemes that can be used with the TLS13_GOST
cipher suites have the following values:
gostr34102012_256a = 0x0709;
gostr34102012_256b = 0x070A;
gostr34102012_256c = 0x070B;
gostr34102012_256d = 0x070C;
gostr34102012_512a = 0x070D;
Smyshlyaev, et al. Expires December 12, 2021 [Page 3]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
gostr34102012_512b = 0x070E;
gostr34102012_512c = 0x070F.
Each TLS13_GOST signature scheme specifies a pair (signature
algorithm, elliptic curve) such that:
o The signature algorithm is the GOST R 34.10-2012 algorithm
[RFC7091].
o The elliptic curve is one of the curves defined in Section 5.2.
Additionally, this document specifies the key exchange and
authentication process in case of negotiating TLS13_GOST cipher
suites (see Section 6).
2. Conventions Used in This Document
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.
3. Basic Terms and Definitions
This document uses the following terms and definitions for the sets
and operations on the elements of these sets:
B_t the set of byte strings of length t, t >= 0, for t =
0 the B_t set consists of a single empty string of
zero length. If A is an element of B_t, then A =
(a_1, a_2, ... , a_t), where a_1, a_2, ... , a_t are
in {0, ... , 255};
B* the set of all byte strings of a finite length
(hereinafter referred to as strings), including the
empty string;
A[i..j] the string A[i..j] = (a_i, a_{i+1}, ... , a_j) in
B_{j-i+1}, where A = (a_1, a_2, ... , a_t) in B_t and
1<=i<=j<=t;
A[i] the integer a_i in {0, ... , 255}, where A = (a_1,
a_2, ... , a_t) in B_t and 1<=i<=t;
|A| the byte length of the string A;
Smyshlyaev, et al. Expires December 12, 2021 [Page 4]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
A | C the concatenation of strings A and C both belonging
to B*, i.e., a string in B_{|A|+|C|}, where the left
substring in B_|A| is equal to A, and the right
substring in B_|C| is equal to C;
i & j bitwise AND of integers i and j;
STR_t the byte string STR_t(i) = (i_1, ... , i_t) in B_t
corresponding to an integer i = 256^{t-1} * i_1 + ...
+ 256 * i_{t-1} + i_t (the interpretation of the
integer as a byte string in big-endian format);
str_t the byte string str_t(i) = (i_1, ... , i_t) in B_t
corresponding to an integer i = 256^{t-1} * i_t + ...
+ 256 * i_2 + i_1 (the interpretation of the integer
as a byte string in little-endian format);
k the length of the block cipher key in bytes;
n the length of the block cipher block in bytes;
IVlen the length of the initialization vector in bytes;
S the length of the authentication tag in bytes;
E_i the elliptic curve indicated by client in
"supported_groups" extension;
O_i the zero point of the elliptic curve E_i;
m_i the order of group of points belonging to the
elliptic curve E_i;
q_i the cyclic subgroup order of group of points
belonging to the elliptic curve E_i;
h_i the cyclic subgroup cofactor which is equal to m_i /
q_i;
Q_sign the public key stored in endpoint's certificate;
d_sign the private key that corresponds to the Q_sign key;
P_i the point of the elliptic curve E_i of the order q_i;
(d_C^i, Q_C^i) the client's ephemeral key pair which consists of the
private key and the public key corresponding to the
elliptic curve E_i;
Smyshlyaev, et al. Expires December 12, 2021 [Page 5]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
(d_S^i, Q_S^i) the server's ephemeral key pair which consists of the
private key and the public key corresponding to the
elliptic curve E_i.
4. Cipher Suite Definition
The cipher suite value is used to indicate a record protection
algorithm and a hash algorithm which an endpoint supports (see
Section 4.1.2 of [RFC8446]).
This section defines the following four TLS13_GOST cipher suites that
can be used to support Russian cryptographic algorithms:
CipherSuite TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_L = {0xC1, 0x03};
CipherSuite TLS_GOSTR341112_256_WITH_MAGMA_MGM_L = {0xC1, 0x04};
CipherSuite TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_S = {0xC1, 0x05};
CipherSuite TLS_GOSTR341112_256_WITH_MAGMA_MGM_S = {0xC1, 0x06};
Each cipher suite specifies a pair of the record protection algorithm
(see Section 4.1) and the hash algorithm (Section 4.2).
4.1. Record Protection Algorithm
In accordance with Section 5.2 of [RFC8446] the record protection
algorithm translates a TLSPlaintext structure into a TLSCiphertext
structure. If TLS13_GOST cipher suite is negotiated, the
encrypted_record field of the TLSCiphertext structure MUST be set to
the AEADEncrypted value computed as follows:
AEADEncrypted = AEAD-Encrypt(sender_record_write_key, nonce,
associated_data, plaintext),
where
o the AEAD-Encrypt function is defined in Section 4.1.1;
o the sender_record_write_key is derived from the sender_write_key
(see Section 7.3 of [RFC8446]) using TLSTREE function defined in
Section 4.1.2 and sequence number seqnum as follows:
sender_record_write_key = TLSTREE(sender_write_key, seqnum);
o the nonce value is derived from the record sequence number seqnum
and the sender_write_iv value (see Section 7.3 of [RFC8446]) in
accordance with Section 5.3 of [RFC8446];
Smyshlyaev, et al. Expires December 12, 2021 [Page 6]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
o the associated_data value is the record header that is generated
in accordance with Section 5.2 of [RFC8446];
o the plaintext value is the TLSInnerPlaintext structure encoded in
accordance with Section 5.2 of [RFC8446].
Note1: The AEAD-Encrypt function is exactly the same as the AEAD-
Encrypt function defined in [RFC8446] except the key (the first
argument) is calculated from the sender_write_key and sequence number
seqnum for each message separately to support external re-keying
approach according to [RFC8645].
Note2: The record sequence number is the value in the range 0-SNMAX,
where the SNMAX value is defined in Section 4.1.3. The SNMAX
parameter is specified by the particular TLS13_GOST cipher suite to
limit the amount of data that can be encrypted under the same traffic
key material (sender_write_key, sender_write_iv).
The record deprotection algorithm reverses the process of the record
protection. In order to decrypt and verify the protected record with
sequence number seqnum the algorithm takes as input the
sender_record_write_key is derived from the sender_write_key, nonce,
associated_data and the AEADEncrypted value and outputs the res value
which is either the plaintext or an error indicating that the
decryption failed. If TLS13_GOST cipher suite is negotiated, the res
value MUST be computed as follows:
res = AEAD-Decrypt(sender_record_write_key, nonce,
associated_data, AEADEncrypted),
where the AEAD-Decrypt function is defined in Section 4.1.1.
Note: The AEAD-Decrypt function is exactly the same as the AEAD-
Decrypt function defined in [RFC8446] except the key (the first
argument) is calculated from the sender_write_key and sequence number
seqnum for each message separately to support external re-keying
approach according to [RFC8645].
4.1.1. AEAD Algorithm
The AEAD-Encrypt and AEAD-Decrypt functions are defined as follows.
Smyshlyaev, et al. Expires December 12, 2021 [Page 7]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
+-------------------------------------------------------------------+
| AEAD-Encrypt(K, nonce, A, P) |
|-------------------------------------------------------------------|
| Input: |
| - encryption key K in B_k, |
| - unique vector nonce in B_IVlen, |
| - associated authenticated data A in B_r, r >= 0, |
| - plaintext P in B_t, t >= 0. |
| Output: |
| - ciphertext C in B_{|P|}, |
| - authentication tag T in B_S. |
|-------------------------------------------------------------------|
| 1. MGMnonce = STR_1(nonce[1] & 0x7f) | nonce[2..IVlen]; |
| 2. (MGMnonce, A, C, T) = MGM-Encrypt(K, MGMnonce, A, P); |
| 3. Return C | T. |
+-------------------------------------------------------------------+
+-------------------------------------------------------------------+
| AEAD-Decrypt(K, nonce, A, C | T) |
|-------------------------------------------------------------------|
| Input: |
| - encryption key K in B_k, |
| - unique vector nonce in B_IVlen, |
| - associated authenticated data A in B_r, r >= 0, |
| - ciphertext C in B_t, t >= 0, |
| - authentication tag T in B_S. |
| Output: |
| - plaintext P in B_{|C|} or FAIL. |
|-------------------------------------------------------------------|
| 1. MGMnonce = STR_1(nonce[1] & 0x7f) | nonce[2..IVlen]; |
| 2. res' = MGM-Decrypt(K, MGMnonce, A, C, T); |
| 3. IF res' = FAIL then return FAIL; |
| 4. IF res' = (A, P) then return P. |
+-------------------------------------------------------------------+
where
o MGM-Encrypt and MGM-Decrypt functions are defined in [DraftMGM].
The size of the authentication tag T is equal to n bytes (S = n).
The size of the nonce parameter is equal to n bytes (IVlen = n).
The cipher suites TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_L and
TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_S MUST use Kuznyechik
[RFC7801] as a base block cipher for the AEAD algorithm. The block
length n is 16 bytes (n = 16) and the key length k is 32 bytes (k =
32).
Smyshlyaev, et al. Expires December 12, 2021 [Page 8]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
The cipher suites TLS_GOSTR341112_256_WITH_MAGMA_MGM_L and
TLS_GOSTR341112_256_WITH_MAGMA_MGM_S MUST use Magma [GOST3412-2015]
as a base block cipher for the AEAD algorithm. The block length n is
8 bytes (n = 8) and the key length k is 32 bytes (k = 32).
4.1.2. TLSTREE
The TLS13_GOST cipher suites use the TLSTREE function for the
external re-keying approach (see [RFC8645]). The TLSTREE function is
defined as follows:
TLSTREE(K_root, i) = KDF_3(KDF_2(KDF_1(K_root, STR_8(i & C_1)),
STR_8(i & C_2)), STR_8(i & C_3)),
where
o K_root in B_32;
o i in {0, 1, ... , 2^64 - 1};
o KDF_j(K, D), j = 1, 2, 3, is the key derivation function defined
as follows:
KDF_1(K, D) = KDF_GOSTR3411_2012_256(K, "level1", D),
KDF_2(K, D) = KDF_GOSTR3411_2012_256(K, "level2", D),
KDF_3(K, D) = KDF_GOSTR3411_2012_256(K, "level3", D),
where the KDF_GOSTR3411_2012_256 function is defined in [RFC7836],
K in B_32, D in B_8.
o C_1, C_2, C_3 are constants defined by the particular cipher suite
as follows:
Smyshlyaev, et al. Expires December 12, 2021 [Page 9]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
+------------------------------------------+----------------------+
| CipherSuites | C_1, C_2, C_3 |
+------------------------------------------+----------------------+
|TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_L |C_1=0xf800000000000000|
| |C_2=0xfffffff000000000|
| |C_3=0xffffffffffffe000|
+------------------------------------------+----------------------+
|TLS_GOSTR341112_256_WITH_MAGMA_MGM_L |C_1=0xffe0000000000000|
| |C_2=0xffffffffc0000000|
| |C_3=0xffffffffffffff80|
+------------------------------------------+----------------------+
|TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_S |C_1=0xffffffffe0000000|
| |C_2=0xffffffffffff0000|
| |C_3=0xfffffffffffffff8|
+------------------------------------------+----------------------+
|TLS_GOSTR341112_256_WITH_MAGMA_MGM_S |C_1=0xfffffffffc000000|
| |C_2=0xffffffffffffe000|
| |C_3=0xffffffffffffffff|
+------------------------------------------+----------------------+
Table 1
4.1.3. SNMAX parameter
The SNMAX parameter is the maximum number of records encrypted under
the same traffic key material (sender_write_key and sender_write_iv)
and is defined by the particular cipher suite as follows:
+------------------------------------------+--------------------+
| CipherSuites | SNMAX |
+------------------------------------------+--------------------+
|TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_L | SNMAX = 2^64 - 1 |
+------------------------------------------+--------------------+
|TLS_GOSTR341112_256_WITH_MAGMA_MGM_L | SNMAX = 2^64 - 1 |
+------------------------------------------+--------------------+
|TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_S | SNMAX = 2^42 - 1 |
+------------------------------------------+--------------------+
|TLS_GOSTR341112_256_WITH_MAGMA_MGM_S | SNMAX = 2^39 - 1 |
+------------------------------------------+--------------------+
Table 2
4.2. Hash Algorithm
The Hash algorithm is used for key derivation process (see
Section 7.1 of [RFC8446]), Finished message calculation (see
Section 4.4.4 of [RFC8446]), Transcript-Hash function computation
Smyshlyaev, et al. Expires December 12, 2021 [Page 10]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
(see Section 4.4.1 of [RFC8446]), PSK binder value calculation (see
Section 4.2.11.2 of [RFC8446]), external re-keying approach (see
Section 4.1.2) and other purposes.
In case of negotiating a TLS13_GOST cipher suite the Hash algorithm
MUST be the GOST R 34.11-2012 [RFC6986] hash algorithm with 32-byte
(256-bit) hash value.
5. Signature Scheme Definition
The signature scheme value is used to indicate a single signature
algorithm and a curve that can be used in digital signature (see
Section 4.2.3 of [RFC8446]).
This section defines the following seven TLS13_GOST signature schemes
that can be used to support Russian cryptographic algorithms:
enum {
gostr34102012_256a(0x0709),
gostr34102012_256b(0x070A),
gostr34102012_256c(0x070B),
gostr34102012_256d(0x070C),
gostr34102012_512a(0x070D),
gostr34102012_512b(0x070E),
gostr34102012_512c(0x070F)
} SignatureScheme;
If TLS13_GOST cipher suite is negotiated and authentication via
certificates is required one of the TLS13_GOST signature schemes
listed above SHOULD be used.
Each signature scheme specifies a pair of the signature algorithm
(see Section 5.1) and the elliptic curve (see Section 5.2). The
procedure to calculate the signature value using TLS13_GOST signature
schemes is defined in Section 5.3.
5.1. Signature Algorithm
Signature algorithms corresponding to the TLS13_GOST signature
schemes are defined as follows:
Smyshlyaev, et al. Expires December 12, 2021 [Page 11]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
+------------------+--------------------------------------+--------+
| SignatureScheme | Signature Algorithm | Refe- |
| Value | | rences |
+------------------+--------------------------------------+--------+
|gostr34102012_256a|GOST R 34.10-2012 , 32-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
|gostr34102012_256b|GOST R 34.10-2012 , 32-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
|gostr34102012_256c|GOST R 34.10-2012 , 32-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
|gostr34102012_256d|GOST R 34.10-2012 , 32-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
|gostr34102012_512a|GOST R 34.10-2012 , 64-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
|gostr34102012_512b|GOST R 34.10-2012 , 64-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
|gostr34102012_512c|GOST R 34.10-2012 , 64-byte key length|RFC 7091|
+------------------+--------------------------------------+--------+
Table 3
5.2. Elliptic Curve
Elliptic curves corresponding to the TLS13_GOST signature schemes are
defined as follows:
+------------------+--------------------------------------+--------+
| SignatureScheme | Curve Identifier Value | Refe- |
| Value | | rences |
+------------------+--------------------------------------+--------+
|gostr34102012_256a| id-tc26-gost-3410-2012-256-paramSetA |RFC 7836|
+------------------+--------------------------------------+--------+
|gostr34102012_256b|id-GostR3410-2001-CryptoPro-A-ParamSet|RFC 4357|
+------------------+--------------------------------------+--------+
|gostr34102012_256c|id-GostR3410-2001-CryptoPro-B-ParamSet|RFC 4357|
+------------------+--------------------------------------+--------+
|gostr34102012_256d|id-GostR3410-2001-CryptoPro-C-ParamSet|RFC 4357|
+------------------+--------------------------------------+--------+
|gostr34102012_512a| id-tc26-gost-3410-12-512-paramSetA |RFC 7836|
+------------------+--------------------------------------+--------+
|gostr34102012_512b| id-tc26-gost-3410-12-512-paramSetB |RFC 7836|
+------------------+--------------------------------------+--------+
|gostr34102012_512c| id-tc26-gost-3410-2012-512-paramSetC |RFC 7836|
+------------------+--------------------------------------+--------+
Table 4
Smyshlyaev, et al. Expires December 12, 2021 [Page 12]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
5.3. SIGN function
If TLS13_GOST signature scheme is used, the signature value in
CertificateVerify message (see Section 6.3.4) MUST be calculated
using the SIGN function defined as follows:
+-----------------------------------------------------+
| SIGN(d_sign, M) |
|-----------------------------------------------------|
| Input: |
| - the sign key d_sign: 0 < d_sign < q; |
| - the byte string M in B*. |
| Output: |
| - signature value sgn in B_{2*l}. |
|-----------------------------------------------------|
| 1. (r, s) = SIGNGOST(d_sign, M) |
| 2. Return str_l(r) | str_l(s). |
|-----------------------------------------------------+
where
o q is the subgroup order of group of points of the elliptic curve;
o l is defined as follows:
* l = 32 for gostr34102012_256a, gostr34102012_256b,
gostr34102012_256c and gostr34102012_256d signature schemes;
* l = 64 for gostr34102012_512a, gostr34102012_512b and
gostr34102012_512c signature schemes;
o SIGNGOST is an algorithm which takes as an input private key
d_sign and message M and returns a pair of integers (r, s)
calculated during signature generation process in accordance with
the GOST R 34.10-2012 signature algorithm (see Section 6.1 of
[RFC7091]).
Note: The signature value sgn is the concatenation of two strings
that are byte representations of r and s values in the little-endian
format.
6. Key Exchange and Authentication
Key exchange and authentication process in case of using TLS13_GOST
cipher suites is defined in Section 6.1, Section 6.2 and Section 6.3.
Smyshlyaev, et al. Expires December 12, 2021 [Page 13]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
6.1. Key Exchange
TLS13_GOST cipher suites support three basic key exchange modes which
are defined in [RFC8446]: ECDHE, PSK-only and PSK-with-ECDHE.
Note: In accordance with [RFC8446] TLS 1.3 also supports key exchange
modes based on Diffie-Hellman protocol over finite fields. However,
TLS13_GOST cipher suites MUST use only modes based on Diffie-Hellman
protocol over elliptic curves.
In accordance with [RFC8446] PSKs can be divided into two types:
o internal PSKs which can be established during the previous
connection;
o external PSKs which can be established out of band.
If TLS13_GOST cipher suite is negotiated, PSK-only key exchange mode
SHOULD be established only via the internal PSKs, and external PSKs
SHOULD be used only in PSK-with-ECDHE mode (see more in Section 9).
If TLS13_GOST cipher suite is negotiated and ECDHE or PSK-with-ECDHE
key exchange mode is used the ECDHE shared secret value should be
calculated in accordance with Section 6.1.1 on the basis of one of
the elliptic curves defined in Section 6.1.2.
6.1.1. ECDHE Shared Secret Calculation
If TLS13_GOST cipher suite is negotiated, ECDHE shared secret value
should be calculated in accordance with Section 6.1.1.1 and
Section 6.1.1.2. The public ephemeral keys used to obtain ECDHE
shared secret value should be represented in format described in
Section 6.1.1.3.
6.1.1.1. ECDHE Shared Secret Calculation on Client Side
The client calculates ECDHE shared secret value in accordance with
the following steps:
1. Chooses from all supported curves E_1, ..., E_R the set of curves
E_{i_1}, ..., E_{i_r}, 1 <= i_1 <= i_r <= R, where
o r >= 1 in the case of the first ClientHello message;
o r = 1 in the case of responding to HelloRetryRequest message,
E_{i_1} corresponds to the curve indicated in the "key_share"
extension in the HelloRetryRequest message.
Smyshlyaev, et al. Expires December 12, 2021 [Page 14]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
2. Generates ephemeral key pairs (d_C^{i_1}, Q_C^{i_1}), ...,
(d_C^{i_r}, Q_C^{i_r}) corresponding to the curves E_{i_1}, ...,
E_{i_r}, where for each i in {i_1, ..., i_r}:
o d_C^i is chosen from {1, ..., q_i - 1} at random;
o Q_C^i = d_C^i * P_i.
3. Sends ClientHello message specified in accordance with
Section 4.1.2 of [RFC8446] and Section 6.3.1, which contains:
o "key_share" extension with public ephemeral keys Q_C^{i_1}, ...,
Q_C^{i_r} generated in accordance with Section 4.2.8 of [RFC8446];
o "supported_groups" extension with supported curves E_1, ..., E_R
generated in accordance with Section 4.2.7 of [RFC8446].
Note: Client MAY send an empty "key_share" extension in the first
ClientHello in order to request group selection from the server in
the HelloRetryRequest message and to generate ephemeral key for the
selected group only. The ECDHE value may be calculated without
sending HelloRetryRequest, if the "key_share" extension in the first
ClientHello message consists the value corresponded to the curve that
will be selected by the server.
4. In case of receiving HelloRetryRequest message client MUST return
to step 1 and correct parameters in accordance with Section 4.1.2 of
[RFC8446]. In case of receiving ServerHello message client proceeds
to the next step. In other cases client MUST terminate the
connection with "unexpected_message" alert.
5. Extracts curve E_res and ephemeral key Q_S^res, res in {1, ...,
R}, from ServerHello message and checks whether the Q_S^res belongs
to E_res. If this check fails, the client MUST abort the handshake
with "handshake_failure" alert.
6. Generates Q^ECDHE:
Q^ECDHE = (X^ECDHE, Y^ECDHE) = (h_res * d_C^res) * Q_S^res.
7. Client MUST check whether the computed shared secret Q^ECDHE is
not equal to the zero point O_res. If this check fails, the client
MUST abort the handshake with "handshake_failure" alert.
8. Shared secret value ECDHE is the byte representation of the
coordinate X^ECDHE of point Q^ECDHE in the little-endian format:
ECDHE = str_{coordinate_length}(X^ECDHE),
Smyshlyaev, et al. Expires December 12, 2021 [Page 15]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
where the coordinate_length value is defined by the particular
elliptic curve (see Section 6.1.2).
6.1.1.2. ECDHE Shared Secret Calculation on Server Side
Upon receiving the ClientHello message, the server calculates ECDHE
shared secret value in accordance with the following steps:
1. Chooses the curve E_res, res in {1, ..., R}, from the list of the
curves E_1, ..., E_R indicated in "supported_groups" extension in
ClientHello message and the corresponding public ephemeral key value
Q_C^res from the list Q_C^{i_1}, ..., Q_C^{i_r}, 1 <= i_1 <= i_r <=
R, indicated in "key_share" extension. If no corresponding public
ephemeral key value is found (res in {1, ..., R}\{i_1, ..., i_r}),
server MUST send HelloRetryRequest message with "key_share" extension
indicating the selected elliptic curve E_res and wait for the new
ClientHello message.
2. Checks whether Q_C^res belongs to E_res. If this check fails,
the server MUST abort the handshake with "handshake_failure" alert.
3. Generates ephemeral key pair (d_S^res, Q_S^res) corresponding to
E_res:
o d_S^res is chosen from {1, ..., q_res - 1} at random;
o Q_S^res = d_S^res * P_res.
4. Sends ServerHello message generated in accordance with
Section 4.1.3 of [RFC8446] and Section 6.3.1 with "key_share"
extension which contains public ephemeral key value Q_S^res
corresponding to E_res.
5. Generates Q^ECDHE:
Q^ECDHE = (X^ECDHE, Y^ECDHE) = (h_res * d_S^res) * Q_C^res.
6. Server MUST check whether the computed shared secret Q^ECDHE is
not equal to the zero point O_res. If this check fails, the server
MUST abort the handshake with "handshake_failure" alert.
7. Shared secret value ECDHE is the byte representation of the
coordinate X^ECDHE of point Q^ECDHE in the little-endian format:
ECDHE = str_{coordinate_length}(X^ECDHE),
where the coordinate_length value is defined by the particular
elliptic curve (see Section 6.1.2).
Smyshlyaev, et al. Expires December 12, 2021 [Page 16]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
6.1.1.3. Public ephemeral key representation
This section defines the representation format of the public
ephemeral keys generated during ECDHE shared secret calculation (see
Section 6.1.1.1 and Section 6.1.1.2).
If TLS13_GOST cipher suite is negotiated and ECDHE or PSK-with-ECDHE
key exchange mode is used, the public ephemeral key Q indicated in
the KeyShareEntry.key_exchange field MUST contain the data defined by
the following structure:
struct {
opaque X[coordinate_length];
opaque Y[coordinate_length];
} PlainPointRepresentation;
where X and Y, respectively, contain the byte representations of the
x and the y values of point Q (Q = (x, y)) in the little-endian
format and are specified as follows:
X = str_{coordinate_length}(x);
Y = str_{coordinate_length}(y).
The coordinate_length value is defined by the particular elliptic
curve (see Section 6.1.2).
6.1.2. Values for the TLS Supported Groups Registry
The "supported_groups" extension is used to indicate the set of the
elliptic curves supported by an endpoint and is defined in
Section 4.2.7 [RFC8446]. This extension is always contained in
ClientHello message and optionally in EncryptedExtensions message.
This section defines the following seven elliptic curves that can be
used to support Russian cryptographic algorithms:
enum {
GC256A(0x22), GC256B(0x23), GC256C(0x24), GC256D(0x25),
GC512A(0x26), GC512B(0x27), GC512C(0x28)
} NamedGroup;
Smyshlyaev, et al. Expires December 12, 2021 [Page 17]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
If TLS13_GOST cipher suite is negotiated and ECDHE or PSK-with-ECDHE
key exchange mode is established, one of the elliptic curves listed
above SHOULD be used.
Each curve corresponds to the particular identifier and specifies the
value of coordinate_length parameter (see "cl" column) as follows:
+-----------+--------------------------------------+----+---------+
|Description| Curve Identifier Value | cl |Reference|
+-----------+--------------------------------------+----+---------+
| GC256A | id-tc26-gost-3410-2012-256-paramSetA | 32 | RFC 7836|
+-----------+--------------------------------------+----+---------+
| GC256B |id-GostR3410-2001-CryptoPro-A-ParamSet| 32 | RFC 4357|
+-----------+--------------------------------------+----+---------+
| GC256C |id-GostR3410-2001-CryptoPro-B-ParamSet| 32 | RFC 4357|
+-----------+--------------------------------------+----+---------+
| GC256D |id-GostR3410-2001-CryptoPro-C-ParamSet| 32 | RFC 4357|
+-----------+--------------------------------------+----+---------+
| GC512A | id-tc26-gost-3410-12-512-paramSetA | 64 | RFC 7836|
+-----------+--------------------------------------+----+---------+
| GC512B | id-tc26-gost-3410-12-512-paramSetB | 64 | RFC 7836|
+-----------+--------------------------------------+----+---------+
| GC512C | id-tc26-gost-3410-2012-512-paramSetC | 64 | RFC 7836|
+-----------+--------------------------------------+----+---------+
Table 5
Note: The identifier values and the corresponding elliptic curves are
the same as in [DraftGostTLS12].
6.2. Authentication
In accordance with [RFC8446] authentication can happen via signature
with certificate or via symmetric pre-shared key (PSK). The server
side of the channel is always authenticated; the client side is
optionally authenticated.
PSK-based authentication happens as a side effect of key exchange.
If TLS13_GOST cipher suite is negotiated, external PSKs SHOULD be
combined only with the mutual authentication (see more in Section 9).
Certificate-based authentication happens via Authentication messages
and optional CertificateRequest message (sent if client
authentication is required). In case of negotiating TLS13_GOST
cipher suites the signature schemes used for certificate-based
authentication are defined in Section 5 and the Authentication
Smyshlyaev, et al. Expires December 12, 2021 [Page 18]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
messages are specified in Section 6.3.3 and Section 6.3.4. The
CertificateRequest message is specified in Section 6.3.2.
6.3. Handshake Messages
The TLS13_GOST cipher suites specify the ClientHello, ServerHello,
CertificateRequest, Certificate and CertificateVerify handshake
messages that are described in further detail below.
6.3.1. Hello Messages
The ClientHello message is sent when a client first connects to a
server or responds to a HelloRetryRequest message and is specified in
accordance with Section 4.1.2 of [RFC8446].
In order to negotiate a TLS13_GOST cipher suite, the ClientHello
message MUST meet the following requirements.
o The ClientHello.cipher_suites field MUST contain the values
defined in Section 4.
o If server authentication via a certificate is required, the
extension_data field of the "signature_algorithms" extension MUST
contain the values defined in Section 5, which correspond to the
GOST R 34.10-2012 signature algorithm.
o If server authentication via a certificate is required and the
client uses optional "signature_algorithms_cert" extension, the
extension_data field of this extension SHOULD contain the values
defined in Section 5, which correspond to the GOST R 34.10-2012
signature algorithm.
o If client wants to establish TLS 1.3 connection using ECDHE shared
secret value, the extension_data field of the "supported_groups"
extension MUST contain the elliptic curve identifiers defined in
Section 6.1.2.
The ServerHello message is sent by the server in response to a
ClientHello message to negotiate an acceptable set of handshake
parameters based on the ClientHello and is specified in accordance
with Section 4.1.3 of [RFC8446].
In case of negotiating a TLS13_GOST cipher suite, the ServerHello
message MUST meet the following requirements.
o The ServerHello.cipher_suite field MUST contain one of the values
defined in Section 4.
Smyshlyaev, et al. Expires December 12, 2021 [Page 19]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
o If server decides to establish TLS 1.3 connection using ECDHE
shared secret value, the extension_data field of the "key_share"
extension MUST contain the elliptic curve identifier and the
public ephemeral key that satisfy the following conditions.
* The elliptic curve identifier corresponds to a value that was
provided in the "supported_groups" and the "key_share"
extensions in the ClientHello message.
* The elliptic curve identifier is one of the values defined in
Section 6.1.2.
* The public ephemeral key corresponds to the elliptic curve
specified by the KeyShareEntry.group identifier.
6.3.2. CertificateRequest
This message is sent when server requests client authentication via a
certificate and is specified in accordance with Section 4.3.2 of
[RFC8446].
If TLS13_GOST cipher suite is negotiated, the CertificateRequest
message MUST meet the following requirements.
o The extension_data field of the "signature_algorithms" extension
MUST contain only the values defined in Section 5.
o If server uses optional "signature_algorithms_cert" extension, the
extension_data field of this extension SHOULD contain only the
values defined in Section 5.
6.3.3. Certificate
This message is sent to convey the endpoint's certificate chain to
the peer and is specified in accordance with Section 4.4.2 of
[RFC8446].
If TLS13_GOST cipher suite is negotiated, the Certificate message
MUST meet the following requirements.
o Each endpoint's certificate provided to the peer MUST be signed
using the algorithm which corresponds to a signature scheme
indicated by the peer in its "signature_algoritms_cert" extension,
if present (or in the "signature_algorithms" extension,
otherwise).
Smyshlyaev, et al. Expires December 12, 2021 [Page 20]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
o The signature algorithm used for signing certificates SHOULD
correspond to the one of the signature schemes defined in
Section 5.
6.3.4. CertificateVerify
This message is sent to provide explicit proof that an endpoint
possesses the private key corresponding to the public key indicated
in its certificate and is specified in accordance with Section 4.4.3
of [RFC8446].
If TLS13_GOST cipher suite is negotiated, the CertificateVerify
message MUST meet the following requirements.
o The CertificateVerify.algorithm field MUST contain the signature
scheme identifier which corresponds to the value indicated in the
peer's "signature_algorithms" extension and which is one of the
values defined in Section 5.
o The CertificateVerify.signature field contains the sgn value,
which is computed as follows:
sgn = SIGN(d_sign, M),
o where
* the SIGN function is defined in Section 5.3,
* d_sign is the sender long-term private key that corresponds to
the sender long-term public key Q_sign from the sender's
certificate,
* the message M is defined in accordance with Section 4.4.3 of
[RFC8446].
7. IANA Considerations
IANA has added numbers {0xC1, 0x03}, {0xC1, 0x04}, {0xC1, 0x05} and
{0xC1, 0x06} with the names
TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_L,
TLS_GOSTR341112_256_WITH_MAGMA_MGM_L,
TLS_GOSTR341112_256_WITH_KUZNYECHIK_MGM_S,
TLS_GOSTR341112_256_WITH_MAGMA_MGM_S to the "TLS Cipher Suites"
registry with this document as reference, as shown below.
Smyshlyaev, et al. Expires December 12, 2021 [Page 21]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
+----------+-----------------------------+-------+-----------+
| Value | Description |DTLS-OK| Reference |
+----------+-----------------------------+-------+-----------+
|0xC1, 0x03| TLS_GOSTR341112_256_ | N | this RFC |
| | _WITH_KUZNYECHIK_MGM_L | | |
+----------+-----------------------------+-------+-----------+
|0xC1, 0x04| TLS_GOSTR341112_256_ | N | this RFC |
| | _WITH_MAGMA_MGM_L | | |
+----------+-----------------------------+-------+-----------+
|0xC1, 0x05| TLS_GOSTR341112_256_ | N | this RFC |
| | _WITH_KUZNYECHIK_MGM_S | | |
+----------+-----------------------------+-------+-----------+
|0xC1, 0x06| TLS_GOSTR341112_256_ | N | this RFC |
| | _WITH_MAGMA_MGM_S | | |
+----------+-----------------------------+-------+-----------+
Table 6
IANA has added numbers 0x0709, 0x070A, 0x070B, 0x070C, 0x070D, 0x070E
and 0x070F with the names gostr34102012_256a, gostr34102012_256b,
gostr34102012_256c, gostr34102012_256d, gostr34102012_512a,
gostr34102012_512b, gostr34102012_512c to the "TLS SignatureScheme"
registry, as shown below.
+-----------+----------------------+---------+----------+
| Value | Description | DTLS-OK | Reference|
+-----------+----------------------+---------+----------+
| 0x0709 | gostr34102012_256a | N | this RFC |
+-----------+----------------------+---------+----------+
| 0x070A | gostr34102012_256b | N | this RFC |
+-----------+----------------------+---------+----------+
| 0x070B | gostr34102012_256c | N | this RFC |
+-----------+----------------------+---------+----------+
| 0x070C | gostr34102012_256d | N | this RFC |
+-----------+----------------------+---------+----------+
| 0x070D | gostr34102012_512a | N | this RFC |
+-----------+----------------------+---------+----------+
| 0x070E | gostr34102012_512b | N | this RFC |
+-----------+----------------------+---------+----------+
| 0x070F | gostr34102012_512c | N | this RFC |
+-----------+----------------------+---------+----------+
Table 7
Smyshlyaev, et al. Expires December 12, 2021 [Page 22]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
8. Historical considerations
Due to historical reasons in addition to the curve identifier values
listed in Table 5 there exist some additional identifier values that
correspond to the signature schemes as follows.
+--------------------+-------------------------------------------+
| Description | Curve Identifier Value |
+--------------------+-------------------------------------------+
| gostr34102012_256b | id-GostR3410_2001-CryptoPro-XchA-ParamSet |
| | id-tc26-gost-3410-2012-256-paramSetB |
+--------------------+-------------------------------------------+
| gostr34102012_256c | id-tc26-gost-3410-2012-256-paramSetC |
+--------------------+-------------------------------------------+
| gostr34102012_256d | id-GostR3410-2001-CryptoPro-XchB-ParamSet |
| | id-tc26-gost-3410-2012-256-paramSetD |
+--------------------+-------------------------------------------+
Table 8
Client should be prepared to handle any of them correctly if
corresponding signature scheme is included in the
"signature_algorithms" or "signature_algorithms_cert" extensions.
9. Security Considerations
In order to create an effective implementation client and server
SHOULD follow the rules below.
1. While using TLSTREE algorithm function KDF_j, j = 1, 2, 3, SHOULD
be invoked only if the record sequence number seqnum reaches such a
value that
seqnum & C_j != (seqnum - 1) & C_j.
Otherwise the previous value should be used.
2. For each pre-shared key value PSK the binder_key value should be
computed only once within all connections where ClientHello message
contains a "pre_shared_key" extension indicating this PSK value.
In order to ensure the secure TLS 1.3 connection client and server
SHOULD fulfil the following requirements.
1. An internal PSK value is NOT RECOMMENDED to be used to establish
more than one TLS 1.3 connection.
Smyshlyaev, et al. Expires December 12, 2021 [Page 23]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
2. 0-RTT data SHOULD NOT be sent during TLS 1.3 connection. The
reasons for this restriction are that the 0-RTT data is not forward
secret and is not resistant to replay attacks (see more in
Section 2.3 of [RFC8446]).
3. If client authentication is required, server SHOULD NOT send
Application Data, NewSessionTicket and KeyUpdate messages prior to
receiving the client's Authentication messages since any data sent at
that point is being sent to an unauthenticated peer.
4. External PSKs SHOULD be used only in PSK-with-ECDHE mode. In
case of using external PSK in PSK-only mode the attack described in
[Selfie] is possible which leads to the situation when client
establishes connection to itself. One of the mitigations proposed in
[Selfie] is to use certificates, however, in that case, an
impersonation attack as in [AASS19] occurs. If the connections are
established with additional usage of key_share extension (in PSK-
with-ECDHE mode), then the adversary which just echoes messages
cannot reveal the traffic key material (as long as the used group is
secure).
5. In case of using external PSK, the mutual authentication MUST be
provided by the external PSK distribution mechanism between the
endpoints which guarantees that the derived external PSK is unknown
to anyone but the endpoints. In addition, the endpoint roles (i.e.
client and server) MUST be fixed during this mechanism and each role
can match only to one endpoint during the whole external PSK
lifetime.
10. References
10.1. Normative References
[DraftGostTLS12]
Smyshlyaev, S., Belyavsky, D., and M. Saarinen, "GOST
Cipher Suites for Transport Layer Security (TLS) Protocol
Version 1.2", 2021, <https://tools.ietf.org/html/draft-
smyshlyaev-tls12-gost-suites-12>.
[DraftMGM]
Smyshlyaev, S., Nozdrunov, V., Shishkin, V., and E.
Smyshlyaeva, "Multilinear Galois Mode (MGM)", 2021,
<https://tools.ietf.org/html/draft-smyshlyaev-mgm-20>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
Smyshlyaev, et al. Expires December 12, 2021 [Page 24]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
[RFC6986] Dolmatov, V., Ed. and A. Degtyarev, "GOST R 34.11-2012:
Hash Function", RFC 6986, DOI 10.17487/RFC6986, August
2013, <https://www.rfc-editor.org/info/rfc6986>.
[RFC7091] Dolmatov, V., Ed. and A. Degtyarev, "GOST R 34.10-2012:
Digital Signature Algorithm", RFC 7091,
DOI 10.17487/RFC7091, December 2013,
<https://www.rfc-editor.org/info/rfc7091>.
[RFC7801] Dolmatov, V., Ed., "GOST R 34.12-2015: Block Cipher
"Kuznyechik"", RFC 7801, DOI 10.17487/RFC7801, March 2016,
<https://www.rfc-editor.org/info/rfc7801>.
[RFC7836] 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, March 2016,
<https://www.rfc-editor.org/info/rfc7836>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/info/rfc8446>.
[RFC8645] Smyshlyaev, S., Ed., "Re-keying Mechanisms for Symmetric
Keys", RFC 8645, DOI 10.17487/RFC8645, August 2019,
<https://www.rfc-editor.org/info/rfc8645>.
10.2. Informative References
[AASS19] Akhmetzyanova, L., Alekseev, E., Smyshlyaeva, E., and A.
Sokolov, "Continuing to reflect on TLS 1.3 with external
PSK", Cryptology ePrint Archive Report 2019/421, April
2019, <https://eprint.iacr.org/2019/421.pdf>.
[GOST3410-2012]
Federal Agency on Technical Regulating and Metrology,
"Information technology. Cryptographic data security.
Signature and verification processes of [electronic]
digital signature", GOST R 34.10-2012, 2012.
Smyshlyaev, et al. Expires December 12, 2021 [Page 25]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
[GOST3411-2012]
Federal Agency on Technical Regulating and Metrology,
"Information technology. Cryptographic Data Security.
Hashing function", GOST R 34.11-2012, 2012.
[GOST3412-2015]
Federal Agency on Technical Regulating and Metrology,
"Information technology. Cryptographic data security.
Block ciphers", GOST R 34.12-2015, 2015.
[Selfie] Drucker, N. and S. Gueron, "Selfie: reflections on TLS 1.3
with PSK", Cryptology ePrint Archive Report 2019/347,
April 2019, <https://eprint.iacr.org/2019/347.pdf>.
Appendix A. Test Examples
TODO
Appendix B. Contributors
o Lilia Akhmetzyanova
CryptoPro
lah@cryptopro.ru
o Alexandr Sokolov
CryptoPro
sokolov@cryptopro.ru
o Vasily Nikolaev
CryptoPro
nikolaev@cryptopro.ru
o Lidia Nikiforova
CryptoPro
nikiforova@cryptopro.ru
Appendix C. Acknowledgments
Authors' Addresses
Stanislav Smyshlyaev (editor)
CryptoPro
18, Suschevsky val
Moscow 127018
Russian Federation
Phone: +7 (495) 995-48-20
Email: svs@cryptopro.ru
Smyshlyaev, et al. Expires December 12, 2021 [Page 26]
Internet-Draft GOST Cipher Suites for TLS 1.3 June 2021
Evgeny Alekseev
CryptoPro
18, Suschevsky val
Moscow 127018
Russian Federation
Email: alekseev@cryptopro.ru
Ekaterina Griboedova
CryptoPro
18, Suschevsky val
Moscow 127018
Russian Federation
Email: griboedova.e.s@gmail.com
Alexandra Babueva
CryptoPro
18, Suschevsky val
Moscow 127018
Russian Federation
Email: babueva@cryptopro.ru
Smyshlyaev, et al. Expires December 12, 2021 [Page 27]