NAME

       clevis-encrypt-tang - Encrypts using a Tang binding server policy

SYNOPSIS

       clevis encrypt tang CONFIG [-y] < PT > JWE

OVERVIEW

       The clevis encrypt tang command encrypts using a Tang binding server policy. Its only
       argument is the JSON configuration object.

       Clevis provides support for the Tang network binding server. Tang provides a stateless,
       lightweight alternative to escrows. Encrypting data using the Tang pin works like this:

           $ clevis encrypt tang '{"url":"http://tang.srv"}' < PT > JWE
           The advertisement contains the following signing keys:

           _OsIk0T-E2l6qjfdDiwVmidoZjA

           Do you wish to trust these keys? [ynYN] y

       To decrypt the data, just pass it to the clevis decrypt command:

           $ clevis decrypt < JWE > PT

       As you can see above, Tang utilizes a trust-on-first-use workflow. If you already know the
       thumbprint of a trusted key, you can specify it in the configuration at encryption time:

           $ cfg='{"url":"http://tang.srv","thp":"_OsIk0T-E2l6qjfdDiwVmidoZjA"}'
           $ clevis encrypt tang "$cfg" < PT > JWE

       Obtaining the thumbprint of a trusted signing key is easy. If you have access to the Tang
       server, simply execute:

           $ tang-show-keys <PORT>

       where <PORT> is the port that the Tang server is listening on.

       If tang-show-keys is not available, but you have access to the Tang server’s database
       directory, you can execute this instead:

           $ jose jwk thp -i $DBDIR/$SIG.jwk

       Tang can also perform entirely offline encryption if you pre-share the server
       advertisement. You can fetch the advertisement with a simple command (just be careful your
       network isn’t compromised!):

           $ curl -f $URL/adv > adv.jws

       Once you have the advertisement file, just provide it:

           $ clevis encrypt tang '{"url":...,"adv":"adv.jws"}' < PT > JWE

CONFIG

       This command uses the following configuration properties:

       •   url (string) : The base URL of the Tang server (REQUIRED)

       •   thp (string) : The thumbprint of a trusted signing key

       •   adv (string) : A filename containing a trusted advertisement

       •   adv (object) : A trusted advertisement (raw JSON)

OPTIONS

       •   -y : Automatically answer yes for all questions. Use this option for skipping the
           advertisement trust check. This can be useful in automated deployments:

               $ clevis encrypt tang '{"url":...}' -y < PT > JWE

SEE ALSO

       clevis-decrypt(1) <clevis-decrypt.1.adoc>

                                                                           CLEVIS-ENCRYPT-TANG(1)