forked from w3c/webauthn
-
Notifications
You must be signed in to change notification settings - Fork 0
/
draft-jones-webauthn-cose-algorithms.txt
336 lines (208 loc) · 11.5 KB
/
draft-jones-webauthn-cose-algorithms.txt
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
WebAuthn Working Group M. Jones
Internet-Draft Microsoft
Intended status: Informational May 2, 2018
Expires: November 3, 2018
COSE Algorithms for Web Authentication (WebAuthn)
draft-jones-webauthn-cose-algorithms-01
Abstract
The W3C Web Authentication (WebAuthn) specification uses COSE
algorithm identifiers. This specification registers algorithms in
the IANA "COSE Algorithms" registry that are used by WebAuthn that
are not already registered. Also, they are registered in the IANA
"JSON Web Signature and Encryption Algorithms" registry, when not
already registered there.
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 November 3, 2018.
Copyright Notice
Copyright (c) 2018 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
Jones Expires November 3, 2018 [Page 1]
Internet-DraCOSE Algorithms for Web Authentication (WebAuthn) May 2018
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Requirements Notation and Conventions . . . . . . . . . . 2
2. RSASSA-PKCS1-v1_5 Signature Algorithm . . . . . . . . . . . . 2
3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 3
3.1. COSE Algorithms Registrations . . . . . . . . . . . . . . 3
4. Security Considerations . . . . . . . . . . . . . . . . . . . 4
4.1. RSA Key Size Security Considerations . . . . . . . . . . 4
4.2. RSASSA-PKCS1-v1_5 with SHA-2 Security Considerations . . 4
4.3. RSASSA-PKCS1-v1_5 with SHA-1 Security Considerations . . 4
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 4
5.1. Normative References . . . . . . . . . . . . . . . . . . 4
5.2. Informative References . . . . . . . . . . . . . . . . . 5
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 5
Document History . . . . . . . . . . . . . . . . . . . . . . . . 6
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 6
1. Introduction
This specification defines how to use several algorithms with COSE
[RFC8152] that are used by the W3C Web Authentication (WebAuthn)
[WebAuthn] specification. These algorithms are registered in the
IANA "COSE Algorithms" registry [IANA.COSE.Algorithms] and also in
the IANA "JSON Web Signature and Encryption Algorithms" registry
[IANA.JOSE.Algorithms], when not already registered there.
1.1. Requirements Notation and Conventions
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. RSASSA-PKCS1-v1_5 Signature Algorithm
The RSASSA-PKCS1-v1_5 signature algorithm is defined in [RFC8017].
The RSASSA-PKCS1-v1_5 signature algorithm is parameterized with a
hash function (h).
A key of size 2048 bits or larger MUST be used with these algorithms.
Implementations need to check that the key type is 'RSA' when
creating or verifying a signature.
Jones Expires November 3, 2018 [Page 2]
Internet-DraCOSE Algorithms for Web Authentication (WebAuthn) May 2018
The RSASSA-PKCS1-v1_5 algorithms specified in this document are in
the following table.
+-------+-------------------------+---------+-----------------------+
| Name | Value | Hash | Description |
+-------+-------------------------+---------+-----------------------+
| RS256 | TBD (requested | SHA-256 | RSASSA-PKCS1-v1_5 w/ |
| | assignment -257) | | SHA-256 |
| RS384 | TBD (requested | SHA-384 | RSASSA-PKCS1-v1_5 w/ |
| | assignment -258) | | SHA-384 |
| RS512 | TBD (requested | SHA-512 | RSASSA-PKCS1-v1_5 w/ |
| | assignment -259) | | SHA-512 |
| RS1 | TBD (requested | SHA-1 | RSASSA-PKCS1-v1_5 w/ |
| | assignment -65535) | | SHA-1 |
+-------+-------------------------+---------+-----------------------+
Table 1: RSASSA-PKCS1-v1_5 Algorithm Values
3. IANA Considerations
3.1. COSE Algorithms Registrations
This section registers the following values in the IANA "COSE
Algorithms" registry [IANA.COSE.Algorithms].
o Name: RS256
o Value: TBD (requested assignment -257)
o Description: RSASSA-PKCS1-v1_5 w/ SHA-256
o Reference: Section 2 of this document
o Recommended: No
o Name: RS384
o Value: TBD (requested assignment -258)
o Description: RSASSA-PKCS1-v1_5 w/ SHA-384
o Reference: Section 2 of this document
o Recommended: No
o Name: RS512
o Value: TBD (requested assignment -259)
o Description: RSASSA-PKCS1-v1_5 w/ SHA-512
o Reference: Section 2 of this document
o Recommended: No
o Name: RS1
o Value: TBD (requested assignment -65535)
o Description: RSASSA-PKCS1-v1_5 w/ SHA-1
o Reference: Section 2 of this document
o Recommended: Deprecated
Jones Expires November 3, 2018 [Page 3]
Internet-DraCOSE Algorithms for Web Authentication (WebAuthn) May 2018
4. Security Considerations
4.1. RSA Key Size Security Considerations
The security considerations on key sizes for RSA algorithms from
Section 6.1 of [RFC8230] also apply to the RSA algorithms in this
specification.
4.2. RSASSA-PKCS1-v1_5 with SHA-2 Security Considerations
The security considerations on the use of RSASSA-PKCS1-v1_5 with
SHA-2 hash functions from Section 8.3 of [RFC7518] also apply to
their use in this specification. For that reason, these algorithms
are registered as being "Not Recommended".
4.3. RSASSA-PKCS1-v1_5 with SHA-1 Security Considerations
The security considerations on the use of the SHA-1 hash function
from [RFC6194] apply in this specification. For that reason, the
"RS1" algorithm is registered as "Deprecated". It MUST NOT be used
by COSE implementations.
A COSE algorithm identifier for this algorithm is nonetheless being
registered because deployed TPMs continue to use it, and therefore
WebAuthn implementations need a COSE algorithm identifier for "RS1"
when TPM attestations using this algorithm are being represented.
5. References
5.1. Normative References
[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>.
[RFC6194] Polk, T., Chen, L., Turner, S., and P. Hoffman, "Security
Considerations for the SHA-0 and SHA-1 Message-Digest
Algorithms", RFC 6194, DOI 10.17487/RFC6194, March 2011,
<https://www.rfc-editor.org/info/rfc6194>.
[RFC7049] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
October 2013, <https://www.rfc-editor.org/info/rfc7049>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <https://www.rfc-editor.org/info/rfc7515>.
Jones Expires November 3, 2018 [Page 4]
Internet-DraCOSE Algorithms for Web Authentication (WebAuthn) May 2018
[RFC7518] Jones, M., "JSON Web Algorithms (JWA)", RFC 7518,
DOI 10.17487/RFC7518, May 2015,
<https://www.rfc-editor.org/info/rfc7518>.
[RFC8017] Moriarty, K., Ed., Kaliski, B., Jonsson, J., and A. Rusch,
"PKCS #1: RSA Cryptography Specifications Version 2.2",
RFC 8017, DOI 10.17487/RFC8017, November 2016,
<https://www.rfc-editor.org/info/rfc8017>.
[RFC8152] Schaad, J., "CBOR Object Signing and Encryption (COSE)",
RFC 8152, DOI 10.17487/RFC8152, July 2017,
<https://www.rfc-editor.org/info/rfc8152>.
[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>.
[RFC8230] Jones, M., "Using RSA Algorithms with CBOR Object Signing
and Encryption (COSE) Messages", RFC 8230,
DOI 10.17487/RFC8230, September 2017,
<https://www.rfc-editor.org/info/rfc8230>.
5.2. Informative References
[IANA.COSE.Algorithms]
IANA, "COSE Algorithms",
<https://www.iana.org/assignments/cose/
cose.xhtml#algorithms>.
[IANA.JOSE.Algorithms]
IANA, "JSON Web Signature and Encryption Algorithms",
<https://www.iana.org/assignments/jose/
jose.xhtml#web-signature-encryption-algorithms>.
[WebAuthn]
Balfanz, D., Czeskis, A., Hodges, J., Jones, J., Jones,
M., Kumar, A., Liao, A., Lindemann, R., and E. Lundberg,
"Web Authentication: An API for accessing Public Key
Credentials", Candidate Recommendation, World Wide Web
Consortium (W3C) Recommendation-track, March 2018,
<https://w3c.github.io/webauthn/>.
Acknowledgements
Thanks to John Fontana, Jeff Hodges, Tony Nadalin, Jim Schaad, Goeran
Selander, Wendy Seltzer, Sean Turner, and Samuel Weiler for their
roles in registering these algorithm identifiers.
Jones Expires November 3, 2018 [Page 5]
Internet-DraCOSE Algorithms for Web Authentication (WebAuthn) May 2018
Document History
[[ to be removed by the RFC Editor before publication as an RFC ]]
-01
o Updated the requested RS1 value from -262 to -65535 to match the
temporary registration made on 2018-04-19.
o Populated the Acknowledgements section.
-00
o Initial version.
Author's Address
Michael B. Jones
Microsoft
Email: mbj@microsoft.com
URI: http://self-issued.info/
Jones Expires November 3, 2018 [Page 6]