1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
|
Internet Engineering Task Force (IETF) R. Housley
Request for Comments: 8619 Vigil Security
Category: Standards Track June 2019
ISSN: 2070-1721
Algorithm Identifiers for the
HMAC-based Extract-and-Expand Key Derivation Function (HKDF)
Abstract
RFC 5869 specifies the HMAC-based Extract-and-Expand Key Derivation
Function (HKDF) algorithm. This document assigns algorithm
identifiers to the HKDF algorithm when used with three common one-way
hash functions.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
https://www.rfc-editor.org/info/rfc8619.
Copyright Notice
Copyright (c) 2019 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
(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.
Housley Standards Track [Page 1]
^L
RFC 8619 HKDF OIDs June 2019
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 2
1.2. ASN.1 . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. HKDF Algorithm Identifiers . . . . . . . . . . . . . . . . . 2
3. ASN.1 Module . . . . . . . . . . . . . . . . . . . . . . . . 3
4. Security Considerations . . . . . . . . . . . . . . . . . . . 4
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 4
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 5
6.1. Normative References . . . . . . . . . . . . . . . . . . 5
6.2. Informative References . . . . . . . . . . . . . . . . . 6
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
The HKDF algorithm [RFC5869] is a key derivation function based on
the Hashed Message Authentication Code (HMAC). This document assigns
algorithm identifiers to the HKDF algorithm when used with three
common one-way hash functions. These algorithm identifiers are
needed to make use of the HKDF in some security protocols, such as
the Cryptographic Message Syntax (CMS) [RFC5652].
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.
1.2. ASN.1
In this specification, values are generated using ASN.1 [X.680] using
the Basic Encoding Rules (BER) and the Distinguished Encoding Rules
(DER) [X.690].
2. HKDF Algorithm Identifiers
This section assigns three algorithm identifiers to HKDF [RFC5869]
used with three common one-way hash functions that are specified in
[SHS]: SHA-256, SHA-384, and SHA-512. When any of these three object
identifiers appear within the ASN.1 type AlgorithmIdentifier, the
parameters component of that type SHALL be absent.
The specification of AlgorithmIdentifier is available in [RFC5911],
which evolved from the original definition in X.509 [X.509-88].
Housley Standards Track [Page 2]
^L
RFC 8619 HKDF OIDs June 2019
The assigned object identifiers are:
id-alg-hkdf-with-sha256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 28 }
id-alg-hkdf-with-sha384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 29 }
id-alg-hkdf-with-sha512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 30 }
3. ASN.1 Module
This section contains the ASN.1 module for the HKDF algorithm
identifiers. This module imports types from other ASN.1 modules that
are defined in [RFC5912].
HKDF-OID-2019
{ iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1) pkcs-9(9)
smime(16) modules(0) id-mod-hkdf-oid-2019(68) }
DEFINITIONS IMPLICIT TAGS ::=
BEGIN
-- EXPORTS All
IMPORTS
AlgorithmIdentifier{}, KEY-DERIVATION
FROM AlgorithmInformation-2009 -- [RFC5912]
{ iso(1) identified-organization(3) dod(6) internet(1)
security(5) mechanisms(5) pkix(7) id-mod(0)
id-mod-algorithmInformation-02(58) } ;
--
-- Object Identifiers
--
id-alg-hkdf-with-sha256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 28 }
id-alg-hkdf-with-sha384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 29 }
id-alg-hkdf-with-sha512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 30 }
Housley Standards Track [Page 3]
^L
RFC 8619 HKDF OIDs June 2019
--
-- Key Derivation Algorithm Identifiers
--
KeyDevAlgs KEY-DERIVATION ::= {
kda-hkdf-with-sha256 |
kda-hkdf-with-sha384 |
kda-hkdf-with-sha512,
... }
kda-hkdf-with-sha256 KEY-DERIVATION ::= {
IDENTIFIER id-alg-hkdf-with-sha256
PARAMS ARE absent
SMIME-CAPS { IDENTIFIED BY id-alg-hkdf-with-sha256 } }
kda-hkdf-with-sha384 KEY-DERIVATION ::= {
IDENTIFIER id-alg-hkdf-with-sha384
PARAMS ARE absent
SMIME-CAPS { IDENTIFIED BY id-alg-hkdf-with-sha384 } }
kda-hkdf-with-sha512 KEY-DERIVATION ::= {
IDENTIFIER id-alg-hkdf-with-sha512
PARAMS ARE absent
SMIME-CAPS { IDENTIFIED BY id-alg-hkdf-with-sha512 } }
END
4. Security Considerations
Despite the simplicity of HKDF, there are many security
considerations that have been taken into account in the design and
analysis of this construction. An exposition of all of these aspects
is well beyond the scope of this document. Please refer to [EPRINT]
for detailed information, including rationale for the HKDF design.
5. IANA Considerations
One object identifier for the ASN.1 module in Section 3 was assigned
in the "SMI Security for S/MIME Module Identifiers
(1.2.840.113549.1.9.16.0)" registry [IANA-MOD]:
id-mod-hkdf-oid-2019 OBJECT IDENTIFIER ::= {
iso(1) member-body(2) us(840) rsadsi(113549) pkcs(1)
pkcs-9(9) smime(16) mod(0) 68 }
Housley Standards Track [Page 4]
^L
RFC 8619 HKDF OIDs June 2019
Three object identifiers for the HKDF algorithm identifiers were
assigned in the "SMI Security for S/MIME Algorithms
(1.2.840.113549.1.9.16.3)" registry [IANA-ALG]:
id-alg-hkdf-with-sha256 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 28 }
id-alg-hkdf-with-sha384 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 29 }
id-alg-hkdf-with-sha512 OBJECT IDENTIFIER ::= { iso(1) member-body(2)
us(840) rsadsi(113549) pkcs(1) pkcs-9(9) smime(16) alg(3) 30 }
6. References
6.1. Normative References
[SHS] National Institute of Standards and Technology (NIST),
"Secure Hash Standard (SHS)", FIPS PUB 180-4,
DOI 10.6028/NIST.FIPS.180-4, August 2015.
[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>.
[RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
RFC 5652, DOI 10.17487/RFC5652, September 2009,
<https://www.rfc-editor.org/info/rfc5652>.
[RFC5869] Krawczyk, H. and P. Eronen, "HMAC-based Extract-and-Expand
Key Derivation Function (HKDF)", RFC 5869,
DOI 10.17487/RFC5869, May 2010,
<https://www.rfc-editor.org/info/rfc5869>.
[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>.
[X.680] ITU-T, "Information technology -- Abstract Syntax Notation
One (ASN.1): Specification of basic notation",
ITU-T Recommendation X.680, ISO/IEC 8824-1:2015, August
2015.
Housley Standards Track [Page 5]
^L
RFC 8619 HKDF OIDs June 2019
[X.690] ITU-T, "Information technology -- ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER), Canonical
Encoding Rules (CER) and Distinguished Encoding Rules
(DER)", ITU-T Recommendation X.690, ISO/IEC 8825-1:2015,
August 2015.
6.2. Informative References
[EPRINT] Krawczyk, H., "Cryptographic Extraction and Key
Derivation: The HKDF Scheme", Proceedings of CRYPTO 2010,
August 2010, <https://eprint.iacr.org/2010/264.pdf>.
[IANA-ALG] IANA, "SMI Security for S/MIME Algorithms
(1.2.840.113549.1.9.16.3)",
<https://www.iana.org/assignments/smi-numbers/>.
[IANA-MOD] IANA, "SMI Security for S/MIME Module Identifier
(1.2.840.113549.1.9.16.0)",
<https://www.iana.org/assignments/smi-numbers/>.
[RFC5911] Hoffman, P. and J. Schaad, "New ASN.1 Modules for
Cryptographic Message Syntax (CMS) and S/MIME", RFC 5911,
DOI 10.17487/RFC5911, June 2010,
<https://www.rfc-editor.org/info/rfc5911>.
[RFC5912] Hoffman, P. and J. Schaad, "New ASN.1 Modules for the
Public Key Infrastructure Using X.509 (PKIX)", RFC 5912,
DOI 10.17487/RFC5912, June 2010,
<https://www.rfc-editor.org/info/rfc5912>.
[X.509-88] CCITT, "Recommendation X.509: The Directory -
Authentication Framework", 1988.
Author's Address
Russell Housley
Vigil Security, LLC
515 Dranesville Road
Herndon, VA 20170
United States of America
Email: housley@vigilsec.com
Housley Standards Track [Page 6]
^L
|