Multiple signatures on multiple files

"David Wall" <[email protected]> Thu, 25 Jul 2002 16:49:49 -0700
Newsgroups gmane.ietf.xmldsig
Organization Yozons, Inc.
Message-ID <[email protected]>
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I currently have an XML file that we create that includes several files =
(such as Word, Excel, PDF...) that are stored inline with BASE64 =
encoding.  Each of these files can be electronically signed by multiple =
parties using a standard digital signature (which hashes the content of =
a file with some metadata like timestamps, IP addresses, etc.) generated =
for each party.

Clearly, I don't want to have to repeat the encoded file as an element =
in each Object.SignatureProperties for since the file can have multiple =
electronic signatures attached (each are independent of the other =
signatures).

Should I do this by creating an Object element that contains just the =
encoded file (one Object element per file), and then create multiple =
Signature elements (one per each electronic signature) such that is has =
a Reference pointing to the Object.SignatureProperties?  From the =
schema, it doesn't seem that this is possible since the Object element =
is inside the Signature element.  I see something about "detached =
signatures," but it's just complex enough that I'm not sure how I should =
be attacking this.

Thanks,
David

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<DIV><FONT face=3DArial size=3D2>I currently have an XML file that we =
create that=20
includes several files (such as Word, Excel, PDF...) that are stored =
inline with=20
BASE64 encoding.&nbsp; Each of these files can be electronically signed =
by=20
multiple parties using a standard digital signature (which hashes the =
content of=20
a file with some metadata like timestamps, IP addresses, etc.) generated =
for=20
each party.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>Clearly, I don't want to have to repeat =
the encoded=20
file as an element in each Object.SignatureProperties=20
for&nbsp;since&nbsp;the&nbsp;file can have&nbsp;multiple electronic =
signatures=20
attached (each are independent of the other signatures).</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>Should I do this by creating an Object=20
element&nbsp;that contains just the encoded file (one Object =
element&nbsp;per=20
file), and then create multiple Signature elements (one per each =
electronic=20
signature) such that is has a Reference pointing to the=20
Object.SignatureProperties?&nbsp; From the schema, it doesn't seem that =
this is=20
possible since the Object element is inside the Signature element.&nbsp; =
I see=20
something about "detached signatures," but it's just complex enough that =
I'm not=20
sure how I should be attacking this.</FONT></DIV>
<DIV><FONT face=3DArial size=3D2></FONT>&nbsp;</DIV>
<DIV><FONT face=3DArial size=3D2>Thanks,</FONT></DIV>
<DIV><FONT face=3DArial size=3D2>David</FONT></DIV></BODY></HTML>

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