Skip to main content

Address Aliases

Address aliases can be used to configure the set of keys that are allowed to sign transactions for a particular address on the Sui network.

You can use address aliases to:

  • Perform simple key rotation for an address.
  • Grant multiple signers full access to everything owned by an address.
  • Implement more complicated authentication schemes, such as smart wallets with passkeys.
warning

All aliases for a given address have the ability to unilaterally control or take all coins, balances, and other resources owned by the address.

Be extremely careful when making any changes to your aliases! Any new alias you add effectively becomes a joint owner of your address.

How aliases work​

Each address on Sui has a set of aliases. New addresses begin as their own alias. That is, a new address A has the alias set {A}.

You can modify aliases for an address using the Move API in the sui::address_alias module. These modification functions must be invoked as top-level PTB commands and cannot be called from other Move functions.

Some constraints for modifying aliases:

  • An address must always have at least one alias.
  • An address can be removed from its own alias set. For example, you can have an address A which only allows signatures from {B, C}.
  • The maximum number of allowed aliases for an address is 8.

Authenticating transactions with aliased addresses​

Transactions on Sui are configured with two addresses: a sender and a gas_owner (which might or might not be the same). For each configured address, a signature is required from one of the signers in its alias set.

For example, with the following transaction and aliases:

transaction T {
  sender: A
  gas_owner: X
  ...
}

aliases[A] = {A, B}
aliases[X] = {Y}

To be valid, the transaction T would require a signature from either A or B, and a signature from Y.

In this example, even if the transaction had signatures from [B, Y] and not from A, during execution it would nonetheless have access to everything owned by A, and during Move call execution its TxContext::sender would be A.