Re: usb token

From: Juha Laiho (Juha.Laiho@iki.fi)
Date: 04/14/03

  • Next message: AxlsPixel: "Re: Article on WebDAV Vulnerability (MS03-007)" 
    From: Juha Laiho <Juha.Laiho@iki.fi>
Date: Mon, 14 Apr 2003 17:52:01 GMT

    zhongmeiyi@yahoo.com.sg (megan) said:
    >>From what I understand, a digital signature is an encryption of the
    >hash (of the data that's to be signed). Is the data sent to the token
    >where it is hashed and encrypted? Or is the data hashed by some other
    >CSP (perhaps Microsoft Base CSP) and then sent to the token where it
    >is encrypted? If it is the former, is it possible if the data to be
    >signed as really huge?

    Haven't been thinking it this far, but yes, it does make sense that the
    hashing is done outside the token and only the hash is sent into the
    token and the token returns the signature for the hash. But then, hashing
    is, to the best of my knowledge, a single-pass operation, so when
    calculating a hash you can drop the data blocks you've already used for
    the calculation, so it could be done with relatively small amount of RAM. 

    -- 
Wolf  a.k.a.  Juha Laiho     Espoo, Finland
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"...cancel my subscription to the resurrection!" (Jim Morrison)
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