dikikarim2004 / delegated_optin_arc

The goal of this ARC is to allow asset transfers without the receiver having to explicitly opt-in first.

Warning

This code is not fully tested nor has it been audited. Right now it simply serves as a proof of concept.

Processes

Definitions

OPEN_OPT_IN_PROGRAM - The program for the logic signature that can be used by anyone to opt the signing account into assets (source)

OPEN_OPT_IN_SIGNATURE - The signature of OPEN_OPT_IN_PROGRAM

ADDRESS_OPT_IN_PROGRAM - The program for the logic signature that can be used by one specific account to opt the signing account into assets (source)

ADDRESS_OPT_IN_SIGNATURE - The signature of ADRESS_OPT_IN_PROGRAM for a specific account

VERIFIER_LSIG - An lsig whos sole purpose is to verify a given OPEN_OPT_IN_SIGNATURE or ADDRESS_OPT_IN_SIGNATURE against the authorization address of a given account (source)

DELEGATED_OPTIN_APP - A single app deployed on an Algorand network used for storing signatures, verifying delegated opt-ins, and setting expiration times (source)

DYANMO_DB - A centralized server containing a mapping of addresses to signatures

Wallet Onboarding

This is the process for onboarding new users in a wallet (ie. Defly, Pera).

Steps

1. Wallet generates keypair as per usual
2. Wallet prompts user if they want to enable deletgated opt-ins
3. If yes, the wallet will sign OPEN_OPT_IN_PROGRAM with the generated sk
   1. This can be a single click
4. Wallet sends address and lsig signature to DYANMO_DB

On-Chain Signature Storage

This is the process for a user adding their OPEN_OPT_IN_SIGNATURE to box strorage of the master contract. This can be done at any time by any account.

Transaction Group

1. MBR Payment: Payent to DELEGATED_OPTIN_APP to cover cost of storing OPEN_OPT_IN_SIGNATURE in a box
2. VERIFIER_LSIG: Any type of transaction from VERIFIER_LSIG
3. DELEGATED_OPTIN_APP: setOpenOptInSignature
   1. sig - OPEN_OPT_IN_SIGNATURE
   2. acct - The account for which we are adding the OPEN_OPT_IN_SIGNATURE
   3. authAddr - The auth address of the aforementioned account

Open Opt-In

This is the process for initiating a delegated opt in using the OPEN_OPT_IN_PROGRAM.

Steps

1. Attempt to read signature from box in DELEGATED_OPTIN_APP
   1. If missing or invalid, attempt to read signature from DynamoDB
2. Send transaction group below

Transaction Group

1. MBR Payment - A payment transaction from the sender to the account opting in that covers the ASA MBR (0.1 ALGO)
2. Opt In - A opt-in transaction signed by OPEN_OPT_IN_PROGRAM with OPEN_OPT_IN_SIGNATURE
3. DELEGATED_OPTIN_APP: verify

Setting End Time

This is the process for an end user setting an end time for their delegated opt ins. Any opt ins after this time will get rejected.

Transaction Group

1. DELEGATED_OPTIN_APP: setOpenOptInEndTime
   1. timestamp - uint64 timestamp

Open Questions

• Should the first sender be required to put the signature in the box?