gpg-wks-server is a server site implementation of the
Web Key Service. It receives requests for publication, sends
confirmation requests, receives confirmations, and published the key.
It also has features to ease the setup and maintenance of a Web Key
When used with the command --receive a single Web Key Service mail is processed. Commonly this command is used with the option --send to directly send the crerated mails back. See below for an installation example.
The command --cron is used for regualr cleanup tasks. For example non-confirmed requested should be removed after their expire time. It is best to run this command once a day from a cronjob.
The command --list-domains prints all configured domains. Further it creates missing directories for the configuration and prints warnings pertaining to problems in the configuration.
The command --check-key (or just --check) checks whether a key with the given user-id is installed. The process return success in this case; to also print a diagnostic, use option -v. If the key is not installed a diagnostics is printed and the process returns failure; to suppress the diagnostic, use option -q. More than one user-id can be given; see also option with-file.
The command --remove-key uninstalls a key from the WKD. The process return success in this case; to also print a diagnostic, use option -v. If the key is not installed a diagnostics is printed and the process returns failure; to suppress the diagnostic, use option -q.
The commands --install-key and --revoke-key are not yet functional.
gpg-wks-server understands these options:
Use mailaddr as the default sender address.
Add the mail header "name: value" to all outgoing mails.
Directly send created mails using the
Requires installation of that command.
Write the created mail also to file. Note that the value
- for file would write it to stdout.
Also print the directory name for each domain listed by command --list-domains.
With command --check-key print for each user-id, the address, ’i’ for installed key or ’n’ for not installed key, and the filename.
Enable extra informational output.
Disable almost all informational output.
Print version of the program and exit.
Display a brief help page and exit.
The Web Key Service requires a working directory to store keys pending for publication. As root create a working directory:
# mkdir /var/lib/gnupg/wks # chown webkey:webkey /var/lib/gnupg/wks # chmod 2750 /var/lib/gnupg/wks
Then under your webkey account create directories for all your domains. Here we do it for "example.net":
$ mkdir /var/lib/gnupg/wks/example.net
$ gpg-wks-server --list-domains
to create the required sub-directories with the permission set correctly. For each domain a submission address needs to be configured. All service mails are directed to that address. It can be the same address for all configured domains, for example:
$ cd /var/lib/gnupg/wks/example.net $ echo firstname.lastname@example.org >submission-address
The protocol requires that the key to be published is sent with an encrypted mail to the service. Thus you need to create a key for the submission address:
$ gpg --batch --passphrase '' --quick-gen-key email@example.com $ gpg --with-wkd-hash -K firstname.lastname@example.org
The output of the last command looks similar to this:
sec rsa2048 2016-08-30 [SC] C0FCF8642D830C53246211400346653590B3795B uid [ultimate] email@example.com firstname.lastname@example.org ssb rsa2048 2016-08-30 [E]
Take the hash of the string "key-submission", which is "bxzcxpxk8h87z1k7bzk86xn5aj47intu" and manually publish that key:
$ gpg --export-options export-minimal --export \ > -o /var/lib/gnupg/wks/example.net/hu/bxzcxpxk8h87z1k7bzk86xn5aj47intu \ > email@example.com
Make sure that the created file is world readable.
Finally that submission address needs to be redirected to a script
procmail command can
be used for this: Redirect the submission address to the user "webkey"
and put this into webkey’s .procmailrc:
:0 * !^From: firstname.lastname@example.org * !^X-WKS-Loop: webkey.example.net |gpg-wks-server -v --receive \ --header X-WKS-Loop=webkey.example.net \ --from email@example.com --send