Dear Marcos,

I have some proposals for editorial changes.

1. Section 1.2: change "which MAY logically contains" to "which MAY logically 
contain"

2. Section 1.2: "An unsigned widget package is a widget package that does not 
contain any signature files. It is left to the user agent's security policy how 
to deal with unsigned widget packages." Doesn't the same apply to signed widget 
packages, too? There is no W3C right now that specifies how a user agent shall 
deal with signed widget packages. I suggest to delete the sentence "It is left 
to the user agent's security policy how to deal with unsigned widget packages."

3. Section 1.2: "Rules are concatenated by being written next to each other and 
a rule prep ended by * means zero or more." I would suggest to split this 
sentence into two: "Rules are concatenated by being written next to each other. 
A rule prep ended by * means zero or more." What is a "rule prep"?

4. Section 2: change "this specification supports SHA-256 the reference element 
and ds:SignedInfo element" to "this specification supports SHA-256, the 
reference element and ds:SignedInfo element"

5. Section 3: "Implementers are encouraged to provide mechanisms to enable 
end-users to install additional root certificates. Trust in a root certificate 
is established through a security critical mechanism implemented by the user 
agent that is out of scope for this specification." A root certificate could be 
used for TLS as well but we mean certificates for widget package signature 
verification. "additional" could imply that a user agent is always provided 
with at least one certificate which does not need to be the case. Therefore, I 
would like to propose to change this part to "Implementers are encouraged to 
provide mechanisms to enable end-users to install certificates for widget 
package digital signature verification. Trust in a certificate is established 
through a security critical mechanism implemented by the user agent that is out 
of scope for this specification."

6. Section 4: "Process the signature files in the signatures list in descending 
order, with distributor signatures first (if any)." The processing is not 
defined before and it is unclear whether there is a difference between 
processing and signature validation. Suggestion: "Validate the signature files 
in the signatures list in descending order, with distributor signatures first 
(if any)."

7. Section 5.1: change "in [XML-Schema-Datatypes])within" to "in 
[XML-Schema-Datatypes]) within"

8. Section 5.2: change header "Author Signatures" to "Author Signature" because 
we have zero or one author signature.

9. Section 5.2: "and whether two widgets came from the same author": Two signed 
widgets that were signed with the same certificate only indicate that these 
both widgets were signed with the same certificate. The signatures do not 
enable any confidence in the relationship between a widget author and a widget 
signer. There are no means that hinder me as an attacker to strip off all 
widget's signatures, sign it with my own certificate with which I signed 
another but rogue widget from somebody else. Therefore, I would recommend to 
delete this bullet point.

10. Section 5.2: change "A widget package MAY contain zero or one author 
signatures." to "A widget package MAY contain zero or one author signature."

More change proposals may come tomorrow (if identified tomorrow).

Best Regards,

Rainer

*************************************
T-Mobile International
Terminal Technology
Rainer Hillebrand
Head of Terminal Security
Landgrabenweg 151, D-53227 Bonn
Germany

+49 171 5211056 (My T-Mobile)
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E-Mail: rainer.hillebr...@t-mobile.net

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