I confirmed my hypothesis.  When AOO 3.4 is installed over the top of an 
existing (i.e., OpenOffice.org 3.3.0) installation, it does not updated the 
registrymodifications.xcu that is already there.  Since there are no settings 
of options for Save As Password use of SHA1 and Blowfish there, none are there 
after the AOO 3.4 install.  That means only the program-set defaults will kick 
in and the user will be converted to "Save with Password" using SHA256/K 
checksums and AES256 CBC encryption.  

I verified this with AOO 3.4 r1303653 atop OO.o 3.3.0.

 - Dennis

PS: I also confirmed that LibreOffice 3.5.0rc3 is adding chaff to XML files 
that are compressed and encrypted, preventing easy access to known plaintexts 
for attacking the encryptions in the ODF package.  (There is a discussion of 
chaff, among other technicalities at 
<https://issues.apache.org/ooo/show_bug.cgi?id=119090>.)

-----Original Message-----
From: Dennis E. Hamilton [mailto:dennis.hamil...@acm.org] 
Sent: Monday, March 26, 2012 17:16
To: ooo-dev@incubator.apache.org
Cc: tjfraz...@cfl.rr.com; j...@apache.org
Subject: RE: [RELEASE,CODE]: Bug 119090 - Default Encryption Fails for 
Down-Level Implementations

I did more experiments with AOO-dev 3.4 and LO 3.5.0rc3 which I happened to 
have installed where it was easy to test them together.

TEST RESULTS

 1. It is possible to change the default behavior of AOO-dev 3.4 and LO 
3.5.0rc3 (both of which produce AES 256 CBC and SHA256-1k encryptions by 
default) by setting options in registrymodifications.xcu. 

 2. If registrymodifications.xcu is deleted, a new one is created *but* it has 
*no* settings for the SHA1 and Blowfish in ODF12 and these installations 
*revert* to AES256 CBC and SHA256-1k even if their last use was with options 
set for Blowfish CFB and SHA1/1K.

HYPOTHESIS **CONFIRMED**: If an install is done on top of a previous 
installation not supporting AES to update to a later version, no settings for 
this will be added to the "legacy" registrymodifications.xcu and the default 
will go into effect: encryptions will start being done in AES256, surprise, 
surprise.  

RECOMMENDATION:

 1. It looks like registrymodification.xcu is the place where a tool or script 
can do the job when it comes to setting/changing the desired option.

 2. It looks like there must be code changes to set the default to Blowfish and 
SHA1/1K within the application to cover the case where registrymodification.xcu 
doesn't specify an option either way. 

 This last may be in Common.xcs but I am betting that the assured default 
setting is in the constructor initial values in savopt.cxx.  Why?  Because that 
class holds the options and setters and getters for them.  Other software uses 
the setters when processing configuration parameters from elsewhere, with the 
default value delivered by the getter when no configuration parameter provides 
a change.  My money is on that being the place.

 - Dennis

-----Original Message-----
From: Dennis E. Hamilton [mailto:dennis.hamil...@acm.org] 
Sent: Sunday, March 25, 2012 18:15
To: ooo-dev@incubator.apache.org
Cc: tjfraz...@cfl.rr.com
Subject: RE: [RELEASE,CODE]: Bug 119090 - Default Encryption Fails for 
Down-Level Implementations

TJ,

I was doing some nosing around and, based on some information on the Community 
Forums (thank you Hagar), it looks like the settings are controlled in a file 
called registrymodifications.xcu, at least on Windows.  The location will vary 
with different versions of windows.

On windows, you can find one under the installed-user profile, such as 
Documents & Settings\orcmid\Application Data [a hidden file], 
OpenOffice/3/user/registrymodification.xcu for any install since the AES256 has 
been instituted as default.  the *.xcu is actually an XML file and you can find 
the settings by searching for "blowfish" and for "SHA1".

How this works for Mac, Solaris, OS/2, and the various Linus and BSD builds, I 
have no idea.

 - Dennis

-----Original Message-----
From: TJ Frazier [mailto:tjfraz...@cfl.rr.com] 
Sent: Friday, March 23, 2012 11:26
To: ooo-dev@incubator.apache.org
Subject: Re: [RELEASE,CODE]: Bug 119090 - Default Encryption Fails for 
Down-Level Implementations

[ ... ]

... options to consider:

3. User change to config file, to use the new option.

I have suggested a writeup on this, but such instructions are much 
better aimed at the (few?) users who want the "latest and greatest" 
security option, and will do a little work to get it. (Does anybody know 
what that file name is? Given that, I volunteer to update the Release 
Notes.)

4. Macro to toggle the settings.

This could be distributed in a BASIC library (new or existing); no 
extension necessary. User instructions to find and run the macro are 
simple. I may be able to write this; preliminary investigation is 
promising but not certain. I volunteer to try. There are several real 
experts on this list, whom I might ask for help.

/tj/
>
>
>
> [1] https://issues.apache.org/ooo/show_bug.cgi?id=119090
>
> On 19.03.2012 14:48, Jürgen Schmidt wrote:
>> On 3/19/12 2:16 PM, TJ Frazier wrote:
>>> On 3/19/2012 08:48, Jürgen Schmidt wrote:
>>>> Hi,
>>>>
>>>> I think issue 119090 is no show stopper from my point of view. The new
>>>> default provides a better security than before when I understand it
>>>> correct. And if people detect potential problems they can save the
>>>> document again with other settings.
>>>>
>>>> I agree that this is important for interoperability but no show
>>>> stopper.
>>>>
>>>> Any other opinion?
>>>>
>>>> Juergen
>>>>
>>>>
>>> Hi, Jürgen,
>>>
>>> Like Dennis, I'm nervous about this. Perhaps we can handle it with a
>>> mention in the Release Notes; something like,
>>>
>>> PLEASE NOTE: the default options for [technical details here] should
>>> provide your best /individual/ security. However, if you intend to share
>>> the document in secure fashion, the default mode cannot be read by
>>> * previous versions of OpenOffice.org
>>> * current versions of LibreOffice, at least through [version]
>>> * Ms Office [version info]
>>> For compatibility, use the options [details here].
>>>
>>
>> I agree that it make sense to mention it in the release notes.
>>
>> Any volunteer for updating the release notes?
>>
>> Juergen
>
>


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