- From: EKR <ekr@rtfm.com>
- Date: 08 May 2000 08:32:38 -0700
- To: tgindin@us.ibm.com
- Cc: "Joseph M. Reagle Jr." <reagle@w3.org>, "IETF/W3C XML-DSig WG" <w3c-ietf-xmldsig@w3.org>
tgindin@us.ibm.com writes:
> I think we should change, and not solely for consistency reasons.
> Although the DSS specifies SHA-1, it would be fairly easy to use a DSA key
> with RIPEMD-160, and people might well call that signature algorithm
> "dsa-ripe".
We've been over this ground a number of times already. This doesn't
work. There's a substitution attack on DSA unless the standard
clearly specifies which digest algorithm to use [1].
Check the archives
http://lists.w3.org/Archives/Public/w3c-ietf-xmldsig/1999OctDec/0079.html
and sequelae for a description of the attack.
-Ekr
[1] Except that if you use an extension of DSA with a longer q
then you can use different digest algorithms for each size of q.
--
[Eric Rescorla ekr@rtfm.com]
PureTLS - free SSLv3/TLS software for Java
http://www.rtfm.com/puretls/
Received on Monday, 8 May 2000 11:31:47 UTC