From: Hans Hagen <pragma@wxs.nl>
To: ntg-context@ntg.nl
Subject: Re: PDF Signature Fields
Date: Thu, 10 Mar 2016 16:56:03 +0100 [thread overview]
Message-ID: <56E19913.1040607@wxs.nl> (raw)
In-Reply-To: <48cc8851d6cb804e0bff8d3f08d72b27@chemnitz.dyndns.aksdb.de>
On 3/10/2016 11:04 AM, Andreas Schneider wrote:
> Hello Hans,
>
> after comparing eforms and the result of a document edited by Acrobat,
> the relevant portions in the spec (PDF 32000-1:2008) are:
> Section 12.7.4.5, with tables 232 and 233.
>
> From what I see it should be possible to add a field /FT /Sig with and
> without a /Lock dictionary.
> The /Lock dictionary created by Acrobat also specifies the optional
> /Type /SigFieldLock (eforms doesn't, but when in doubt, I trust Adobe
> more than eforms ;-))
>
> Here is an example from the PDF stream of a document manually forged
> with Acrobat:
> %% Object stream: object 167, index 37; original object ID: 475
> <<
> /AP <<
> /N 188 0 R
> >>
> /DA (/Helv 0 Tf 0 g)
> /F 4
> /FT /Sig
> /Lock 187 0 R
> /MK <<
> >>
> /P 196 0 R
> /Rect [
> 253.965
> 163.306
> 525.056
> 186.143
> ]
> /Subtype /Widget
> /T (Gehnehmiger Unterschrift)
> /Type /Annot
>>>
> %% Object stream: object 187, index 57; original object ID: 495
> <<
> /Action /Exclude
> /Fields [
> (Einrichter Name)
> (Einrichters Unterschrift)
> ]
> /Type /SigFieldLock
>>>
>
> ("Einrichter Name" is another Text Field --> /FT /Tx [...] /Subtype
> /Widget [...] /T (Einrichter Name)
> "Einrichters Unterschrift" is another Signature Field)
next beta:
\setupinteraction[state=start]
\starttext
\definefield[x][signature]
\field[x]
\stoptext
> Am 2016-03-09 16:16, schrieb Hans Hagen:
>> On 3/9/2016 2:11 PM, Andreas Schneider wrote:
>>> Hello all,
>>>
>>> is there currently any mechanism in ConTeXt similar to the LaTeX digsig
>>> or eforms package?
>>> I want to add a form field that can be digitally signed (which is now
>>> already possible with Acrobat Reader, not just with Acrobat Pro).
>>>
>>> Additionally (like the mentioned eforms package) it would be nice, if
>>> you could specify other form fields that should be locked once the
>>> signature field is actually signed (according to the PDF spec this is
>>> simply set via a dictionary).
>>
>> it's probably something trivial to implement so what are the relevant
>> fields (paragraphs/tables/dics/fields in the pdf spec) .. i'm not
>> going to reverse engineer some package but start from the spec
>>
>>> Anyway: can this currently be achieved with ConTeXt? If not: is there
>>> any chance to get that feature added sometime? :-)
>>
>> so far i never bothered with anything signature (i must say that i
>> never ran into such docs and it would not make them more valid to me
>> anyway)
>>
>> Hans
>>
>> -----------------------------------------------------------------
>> Hans Hagen | PRAGMA ADE
>> Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
>> tel: 038 477 53 69 | www.pragma-ade.com | www.pragma-pod.nl
>> -----------------------------------------------------------------
> ___________________________________________________________________________________
>
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> to the Wiki!
>
> maillist : ntg-context@ntg.nl /
> http://www.ntg.nl/mailman/listinfo/ntg-context
> webpage : http://www.pragma-ade.nl / http://tex.aanhet.net
> archive : http://foundry.supelec.fr/projects/contextrev/
> wiki : http://contextgarden.net
> ___________________________________________________________________________________
--
-----------------------------------------------------------------
Hans Hagen | PRAGMA ADE
Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
tel: 038 477 53 69 | www.pragma-ade.com | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!
maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage : http://www.pragma-ade.nl / http://tex.aanhet.net
archive : http://foundry.supelec.fr/projects/contextrev/
wiki : http://contextgarden.net
___________________________________________________________________________________
next prev parent reply other threads:[~2016-03-10 15:56 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-03-09 13:11 Andreas Schneider
2016-03-09 15:16 ` Hans Hagen
2016-03-09 15:39 ` Alan BRASLAU
2016-03-09 15:57 ` Hans Hagen
2016-03-09 16:04 ` Andreas Schneider
2016-03-09 16:20 ` Henning Hraban Ramm
2016-03-10 10:04 ` Andreas Schneider
2016-03-10 15:56 ` Hans Hagen [this message]
2016-03-14 13:55 ` Andreas Schneider
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