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Questions tagged [digital-signature]

216 questions
54
votes
6 answers

Is it possible to sign a file using an ssh key?

I use SSH (OpenSSH 5.5p1 on Linux, to be precise). I have a key, on which i have a passphrase. I use this for the usual logging in to computers stuff. Can i also use it to sign files? As i understand it, an SSH key is an RSA (or DSA) key, and during…
Tom Anderson
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28
votes
4 answers

How to verify a digital signature on a PDF on Linux?

I am a Linux desktop user. Someone sends me a PDF file which is digitally signed. It is supposed to be signed using some kind of government / regulated body / official institution issued certificate. Is there a way that I, as a typical end-user,…
TorstenS
  • 431
23
votes
4 answers

GPG - verifying signatures without creating trust chain?

Is it possible to ask gpg (or gpg4win) to just verify whether a file was signed by a particular public key file, without having to import and sign and trust that key? i.e. something like gpg --using-key pubkey.txt --verify message.txt as opposed to…
OJW
  • 2,487
22
votes
9 answers

How to sign a pdf in Okular or other FOSS program?

How do I sign a PDF in Okular? I tried searching for about 20 mins, but I can't find any answers... I have a .png of my signature, and I basically want to insert it into the document on the dotted line. An electronic timestamp etc would also be…
modulitos
  • 534
18
votes
2 answers

How do I allow cross-signed kernel drivers in Windows 10 version 1607 with secure boot enabled?

Windows 10 Version 1607 (aka Anniversary Update) is now enforcing the tightened kernel driver certification which was already announced 2015 as a requirement for Windows 10. The new rule is that all Windows 10 drivers must be digitally signed by…
gollum
  • 486
17
votes
4 answers

Use an unsigned driver in Windows 7 x64

I'm trying to use the RBC9 SpaceNavigator TEST x64 build drivers for my SpaceNavigator 3d joystick so that it can work as a normal joystick in games like Quake. Unfortunately, I get the error "This version of windows requires all drivers to have a…
rjmunro
  • 1,386
16
votes
5 answers

Is it possible to sign archives?

I played with openssl to make a pub/prv key and create a signature of a file and validated it. I toyed with Cryptophane (windows gnupg frontend) and heard about keyservers+played with signing text. I however not ever signed a file archive. If i want…
user3109
14
votes
1 answer

How to sign gmail email with digital signature?

I have my personal digital signature on the special card and the according reader. How can I sign an email (sending it with gmail) with this signature? I am on the latest OSX and use Google Chrome (but can use Windows 7, if it is really required).
LA_
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14
votes
4 answers

Embed a GPG Signature in a PDF File

Is it possible to embed GPG signatures in PDF files the way it can be done with X.509 signatures? (I've been using JSignPDF to sign my invoices so far, but now the law has relaxed a bit, and it doesn't require X.509 anymore (just that I provide some…
Petr Skocik
  • 1,472
11
votes
2 answers

Verify that a GPG-encrypted file is signed by particular user(s)

I've got a file encrypted and signed by GPG. In the man page for gpg, for the --decrypt option, it says: If the decrypted file is signed, the signature is also verified. I'd like to do more than just verify that a signature is valid "if the file…
Craig McQueen
  • 1,301
11
votes
1 answer

How can I verify that a Windows XP POS operating system executable is authentic?

I have a 3rd party firewall that alerted me that msiexec.exe was replaced by another version. The timing didn't correspond to an OS update, so I was worried a bad actor replaced the exe. How can I verify the signature of the exe? EDIT: I found…
Dale
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9
votes
1 answer

Sign & Encrypt vs. Encrypt & Sign - What does GPG do?

I’ve already read the discussion Should we sign-then-encrypt, or encrypt-then-sign? and the paper Defective Sign & Encrypt in S/MIME, PKCS#7, MOSS, PEM, PGP, and XML. My question has to do with what gpg is doing. This has been a bit difficult to…
Diagon
  • 744
9
votes
4 answers

Is there a free PDF printer / distiller that creates signable documents?

I've used various methods (mentioned elsewhere on this site) to create PDFs, using a printer driver or converting from PostScript, etc. The common problem is that if I open any of the output files in the newer versions of Adobe Reader, there's an…
Coderer
  • 1,700
8
votes
1 answer

Microsoft Word and digital signatures using PGP?

I have a document for a project that I am working on with my team, and I need to digitally sign the document in a way that can be verified by other members of the team. The catch is, internally, we are using PGP (the commercial version, I think). …
Kumba
  • 183
8
votes
1 answer

How to verify an email signature from Facebook?

Facebook allows users to add OpenPGP public keys to their profile; these keys can be used to "end-to-end" encrypt notification emails sent from Facebook to your preferred email accounts. – Securing Email Communications from Facebook Facebook…
marianoju
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