On 05/28/2006 12:03 AM, David Shaw wrote: [..snip..] >> David Shaw in a recent message <[EMAIL PROTECTED]> >> about DSA2 said: >>> 3) Allowing truncation of a bigger hash to fit into the however many >>> bits the key allows. >>> >>> As far as I can tell at the moment, PGP 8 allows only #3. That is, >>> if you have a regular DSA key (1024 bits, 160-bit hash), you can use >>> a larger hash like SHA-256 with it. Of course, you still only get >>> 160 bits of strength (you just can't fit 256 bits into a 160 bit >>> field). > > This is a true statement, but not relevant to your question. I was > discussing DSA keys, and you're asking about RSA. I'm asking about hash functions support in general; if a particular piece of sw supports HASH-X in DSA it is reasonable to suppose that the same is with RSA. > You can use any > hash with RSA that you like. There are no restrictions in size or > otherwise. The only thing you have to worry about is whether your > recipient can handle that hash or not. That was the point of message. Asserting that with PGP 8 you can use a larger hash /like/ SHA-256 doesn't necessarily mean that you you are limited to it, someone could understand "you can use larger hashes, like sha256, like sha224, sha384, like sha512, so PGP 8 supports them even if with DSA it uses a truncated result due to the obvious limitations imposed by q".
However, you have cleared all my doubts. -- Q.E.D. ICQ UIN: 301825501 OpenPGP key ID: 0x58D14EB3 Key fingerprint: 00B9 3E17 630F F2A7 FF96 DA6B AEE0 EC27 58D1 4EB3 Check fingerprints before trusting a key! _______________________________________________ Gnupg-users mailing list Gnupg-users@gnupg.org http://lists.gnupg.org/mailman/listinfo/gnupg-users
