I've been doing some more exploring with OpenSSL and have seen one of
the RSA signatures generated by it in a server key exchange message:

engineVerify: DBytes:
00000: 00 01 FF FF FF FF FF FF  FF FF FF FF FF FF FF FF
................
00016: FF FF FF FF FF FF FF FF  FF FF FF FF FF FF FF FF
................
00032: FF FF FF FF FF FF FF FF  FF FF FF FF FF FF FF FF
................
00048: FF FF FF FF FF FF FF FF  FF FF FF FF FF FF FF FF
................
00064: FF FF FF FF FF FF FF FF  FF FF FF FF FF FF FF FF
................
00080: FF FF FF FF FF FF FF FF  FF FF FF 00 64 66 B7 24
............df.$
00096: 40 94 1F 0A B0 12 25 D9  45 FC 4A 4A 42 F4 DA 1A
@.....%.E.JJB...
00112: 5C D3 E0 46 B7 F9 8E C7  33 31 D4 5D ED 02 F6 B3
\..F....31.]....

There are 36 bytes of data there, and they are the MD5 and SHA hashes of
the client and server randoms and the temporary RSA key parameters.

My signature classes expect (and the Java JCE, I think) expect
signatures to be a hash of input data. I guess the hash algorithm could
be null to achieve this result but you need to ensure the input data is
at least 11 bytes less than the key length in bytes.

This is why things are not working out... the data at the end of the
PKCS#1 block in my signatures would be the MD5 hash value of those 36
bytes wrapped in a DigestInfo structure, not simply the 36 bytes
themselves.

I'm guessing OpenSSL has been tested against Netscapes SSL
implementation and shown to work so I'll find a way to do signatures
like this.

--

Regards,
David Taylor

=======================================================================
David Taylor                           e-mail  [EMAIL PROTECTED]
Software Engineer
Forge Research Pty Ltd                 Phone  +61 2 9209 4175
PO Box 598, Alexandria                 Fax    +61 2 9209 4172
NSW 1435, Australia                    Web     http://www.forge.com.au
=======================================================================

______________________________________________________________________
OpenSSL Project                                 http://www.openssl.org
Development Mailing List                       [EMAIL PROTECTED]
Automated List Manager                           [EMAIL PROTECTED]

Reply via email to