AW: [iaik-jce] Signatur

["Dieter Bratko" <Dieter.Bratko@iaik.at>]

Hello,

PKCS#1 RSA signature algorithms do the the DigestInfo wrapping itself.
PKCS#7 actually does not use a "siganture" algorithm, rather it uses
rsaEncryption for "encrypting" the digest. The result actually is the same
since PKCS#7 also uses DigestInfo-wrapping.
The only difference is the signature BIT-STRING representation in PKCS#1.

Regards,
Dieter Bratko

-----Ursprüngliche Nachricht-----
Von: iaik-jce-owner@iaik.tu-graz.ac.at
[mailto:iaik-jce-owner@iaik.tu-graz.ac.at]Im Auftrag von Schneider,
Wolfgang
Gesendet: Donnerstag, 23. November 2000 09:57
An: Iaik-Jce (E-Mail)
Betreff: [iaik-jce] Signatur


Hi,

I have a question how a signature is created.
As far as I know is a signature a hash encrypted with a private key.=20
The hash is packed in a DigestInfo before the encryption with the =
private
key.
Is this correct and is this alwasy true for all signatures? Why is the
DigestInfo Class then only in the package pkcs7?
What is the difference between a pkcs7 signature and a shaRsaSignature, =
can
anyone give an example.

Why all this questions :-)
I have a hash and want to create a signature. But I don=B4t wont to =
recompute
the hash ( which  is done implicitly ). So I have to know how I must =
encrypt
the hash. ( once in a pkcs7 signature and for  plain data in another =
case )

Thanks a lot

Wolfgang Schneider

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*   From: "Dieter Bratko" <Dieter.Bratko@iaik.at>                         *
*   Date: Tue, 28 Nov 2000 18:30:01 +0100                                 *
*   Subject: AW: [iaik-jce] Signatur                                      *
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