IOU's/issued tokens forever blocked from sending back to issuer (Blackhole+DepositAuth)

[Wietse-Livingroom]

Issue Description

Issued tokens on the XRPL can normally be sent back to the issuing account. Doing so will lower the obligation by the issuer, and allow the sender to destroy tokens (lower distribution) or even fully clean out a balance. For example to be able to remove a Trust Line.

When a token is issued as an independent (non-IOU) token, it's a common practice to issue, set the Regular Key to ACCOUNT_ZERO or ACCOUNT_ONE and then disable the master key. This way the issuing account is "black holed": issuing account access is destroyed, the supply cannot be increased and Trust Lines cannot be frozen.

When, before disabling the master key of the issuing account, the DepositAuth flag is set with an AccountSet transaction (on the issuing account), the issuing account will no longer accept incoming transactions (from a non-whitelisted account). If the account is then black holed, no one will ever be able to send back issued tokens to the issuer, as those transactions will fail with a tecNO_PERMISSION error.

Implications

If an issued token can no longer be returned to the issuer one can never voluntarily get rid of the token in a 'clean' way. This would leave people with a Trust Line & reserve that can never be closed & freed up again. A workaround could be to find a random other Trust Line and send off all owned tokens there, but that's a dirty solution (especially for the random recipient). Also, if one is the only holder of the token, there is no other party to send the tokens to, resulting in an forever useless Trust Line & reserve.

Proposed change (please discuss)

• Ignore DepositAuth check for incoming transactions of a token issued by the receiving account: the issuer can already block incoming transactions for issued tokens with a Global Freeze.

[ximinez]

Just to clarify, a Global Freeze does not stop incoming payments to the issuer. https://xrpl.org/freezes.html#global-freeze

[WietseWind]

That's good to know @ximinez - Thanks for that. Learning something every day :)

[mrpunishir]

i am just looking around as most of my assets for some reason have disappeared 👻 it's happened overtime but know they are appearing i can always see them lately but cant access them so maybe in the near future when i can access. I will donate to help Gitthub as for the moment we don't have anything to donate. When the time is right we will do the right thing. Thanks you for your help i hope i can come back spend more time first need to sort out my coins to release the financial burden of me