- From: David Rogers <david.rogers@copperhorses.com>
- Date: Mon, 16 Jul 2012 20:09:35 +0100
- To: <public-webcrypto@w3.org>
- Cc: <S.Durbha@cablelabs.com>
- Message-ID: <000001cd6386$8a566e20$9f034a60$@copperhorses.com>
Hi all,
Please find below a proposal for the base set of mandatory algorithms on
behalf of Seetharama and myself. Our aim has been to baseline but also to at
least give us a 'fresh start'. We didn't think putting loads of legacy in
for the sake of it is going to be either good for the web or good for
security. That said, we've tried to be reasonably pragmatic in the list.
We've also tried to think about small device uses such as mobile. For
example, we have not included SHA-384 because the computational cost is
about the same as SHA-512 so it isn't worth putting it in as a base (for
example for mobile apps). As a reference, this is also mentioned in
RFC-4051:
"2.1.3. SHA-384
Identifier:
http://www.w3.org/2001/04/xmldsig-more#sha384
The SHA-384 algorithm [FIPS-180-2] takes no explicit parameters. An
example of a SHA-384 DigestAlgorithm element is:
<DigestAlgorithm
Algorithm="http://www.w3.org/2001/04/xmldsig-more#sha384" />
A SHA-384 digest is a 384 bit string. The content of the DigestValue
element shall be the base64 [RFC2405] encoding of this string viewed
as a 48-octet stream. Because it takes roughly the same amount of
effort to compute a SHA-384 message digest as a SHA-512 digest and
terseness is usually not a criteria in XML application, consideration
should be given to the use of SHA-512 as an alternative.
"
Anyway, this is a start and I hope we can agree this list as a starting
point:
Encryption Algorithms:
AES-128
AES-256
Encryption Modes:
CTR
CBC
GCM
Hash Functions:
SHA-256
SHA-512
MACs
HMAC with SHA-256
HMAC with SHA-512
Key Agreement
Diffie-Hellman (1024/1536/2048 bit keys)
Key Transport
AES-128 key wrap
AES-256 key wrap
RSAES (1024/1536/2048 bit keys)
Signature Schemes
DSA (1024/1536/2048 keys)
RSASSA (1024/1536/2048 bit keys) with SHA-256
RSASSA (1024/1536/2048 bit keys) with SHA-512
Key Derivation Functions
Concat KDF with SHA-256
Concat KDF with SHA-512
Thanks,
David.
__________________________________________________________________
David Rogers
Director
Copper Horse Solutions Limited
david.rogers@copperhorses.com
Web: http://www.copperhorsesolutions.com
<http://www.copperhorsesolutions.com/>
Blog: http://blog.mobilephonesecurity.org
<http://blog.mobilephonesecurity.org/>
Twitter: http://twitter.com/drogersuk (@drogersuk)
__________________________________________________________________
Received on Monday, 16 July 2012 19:17:55 UTC