How do I verify an asc key fingerprint?

Get the key:

$ wget http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc

Print the key fingerprint with GPG version 1:

$ gpg --with-fingerprint oracle_vbox.asc 
pub  1024D/98AB5139 2010-05-18 Oracle Corporation
                      (VirtualBox archive signing key) <[email protected]>
      Key fingerprint = 7B0F AB3A 13B9 0743 5925  D9C9 5442 2A4B 98AB 5139
sub  2048g/281DDC4B 2010-05-18
      Key fingerprint = 27B0 97CF 8257 4209 C434  8D42 B674 8A65 281D DC4B

Note that the 2nd fingeprint is just the fingerprint of the sub-key.

Print the fingerprint with GPG version 2:

$ gpg2 -n -q --import --import-options import-show  oracle_vbox.asc   
pub   dsa1024 2010-05-18 [SC]
      7B0FAB3A13B907435925D9C954422A4B98AB5139
uid   Oracle Corporation (VirtualBox archive signing key) <[email protected]>
sub   elg2048 2010-05-18 [E]

Note that -n is an alias for --dry-run, i.e. the key isn't actually imported.

Alternatively, to just display the fingerprints:

$ gpg2 -nq --import --import-options import-show --with-colons oracle_vbox.asc \
     | awk -F: '$1 == "fpr" { print $10 }'
7B0FAB3A13B907435925D9C954422A4B98AB5139
27B097CF82574209C4348D42B6748A65281DDC4B

Step 1

$ deb http://download.virtualbox.org/virtualbox/debian artful contrib

Step 2

$ wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add -

Step 3

$ apt-key list

or, equivalently,

$ apt-key finger

which should return

/etc/apt/trusted.gpg
--------------------
pub   rsa4096 2016-04-22 [SC]
      B9F8 D658 297A F3EF C18D  5CDF A2F6 83C5 2980 AECF
uid           [ unknown] Oracle Corporation (VirtualBox archive signing key) <[email protected]>
sub   rsa4096 2016-04-22 [E]

which in turn should be equivalent to

The key fingerprint for oracle_vbox_2016.asc is

B9F8 D658 297A F3EF C18D  5CDF A2F6 83C5 2980 AECF
Oracle Corporation (VirtualBox archive signing key) <[email protected]>

on https://www.virtualbox.org/wiki/Linux_Downloads, either by visual inspection or further command line fu.


Related links:

  • Exchanging keys - GnuPG
  • https://www.torproject.org/docs/verifying-signatures.html.en

Tags:

Gnupg