Extracting SGN files used by the Israeli Court System
The Story
One of my friends has some dealings with the Israeli courts.
The noteworthy (and annoying) part of their digital documents is that these documents are using a novel format instead of some industry standard.
Files arriving by email have the SGN suffix, and the email includes the following footer:
המסמך המצורף חתום דיגיטלית. כדי לצפות בקובץ יש להוריד תוכנה בכתובת :
https://www.court.gov.il/NGCS.Web.Site/DigitalSignature/Court Digital Signature Application.msi
)התוכנה תואמת למערכת הפעלה Windows בלבד(
English Google translation:
The attached document is digitally signed. To view the file you need to download software at:
https://www.court.gov.il/NGCS.Web.Site/DigitalSignature/Court Digital Signature Application.msi
) The software is compatible with Windows operating system only (
This friend doesn’t have Windows, so how can he read those docs?
My solution
From taking a peek in the doc, I saw that it’s basically a ginormous XML, with fields containing the following:
- Original filename
- Content, encoded as base64
- Signer identity
I was willing to skip verifying the signer, and settled instead for just extracting the original file.
THe quick solution is:
xq -r '.DocumentEnvelope.SignaturePackage.Signature.Object.DocumentContent["#text"]' | base64 --decode
xq is a jq-like command for XML. It has a YAML equivalent as well, and was highly useful here.
base64 is a bash utility for decoding/encoding base64 data.
I made a nicer version in my sgn-court-extract repo. I might migrate it to a proper Python script one day.
Feel free to use it yourself!