ckb-anyone-can-pay

CKB anyone-can-pay lock.

RFC Draft

Build

make all-via-docker && cargo test

Quick start

Create

1, create a cell to receive UDT and CKB:

Cell {
    lock: {
        code_hash: <any-one-can-pay>
        args: <pubkey hash>
    }
    data: <UDT amount>
    type: <UDT>
}

2, create a cell to receive only CKB:

Cell {
    lock: {
        code_hash: <any-one-can-pay>
        args: <pubkey hash>
    }
    data: <empty>
    type: <none>
}

3, we can add minimum amount transfer condition:

Cell {
    lock: {
        code_hash: <any-one-can-pay>
        args: <pubkey hash> | <minimum CKB> | <minimum UDT>
    }
    data: <UDT amount>
    type: <UDT>
}

minimum CKB and minimum UDT are two optional args, each occupied a byte, and represent 10 ^ x minimal amount. The default value is 0 which means anyone can transfer any amount to the cell. A transfer must satisfy the minimum CKB or minimum UDT.

If the owner only wants to receive UDT, the owner can set minimum CKB to 255.

Send UDT and CKB

To transfer coins to an anyone-can-pay lock cell, the sender must build an output cell that has the same lock_hash and type_hash to the input anyone-can-pay lock cell; if the input anyone-can-pay cell has no data, the output cell must also be empty.

# inputs
Cell {
    lock: {
        code_hash: <any-one-can-pay>
        args: <pubkey hash> | <minimum CKB: 2>
    }
    data: <empty>
    type: <none>
    capacity: 100
}
...

# outputs
Cell {
    lock: {
        code_hash: <any-one-can-pay>
        args: <pubkey hash> | <minimum CKB: 2>
    }
    data: <empty>
    type: <none>
    capacity: 200
}
...

Signature

The owner can provide a secp256k1 signature to unlock the cell, the signature method is the same as the P2PH.

Unlock a cell with a signature has no restrictions, which helps owner to manage the cell as he wants.