This proposal describes a communication protocol between dapps and Ethereum-enabled DOM environments that allows the Ethereum-enabled DOM environment to choose what information to supply the dapp with and when.
The previous generation of Ethereum-enabled DOM environments follows a pattern of injecting a provider populated with accounts without user consent. This puts users of such environments at risk because malicious websites can use these accounts to view detailed account information and to arbitrarily initiate unwanted transactions on a user's behalf.
This proposal outlines a protocol in which Ethereum-enabled DOM environments can choose to expose no accounts until the user approves account access.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC-2119.
eth_requestAccountsProviders exposed by Ethereum-enabled DOM environments define a new RPC method: eth_requestAccounts. Calling this method may trigger a user interface that allows the user to approve or reject account access for a given dapp. This method returns a Promise that is resolved with an Array of accounts or is rejected with an Error if accounts are not available.
Note: This method is deprecated in favor of the RPC method eth_requestAccounts.
Providers exposed by Ethereum-enabled DOM environments define a new RPC method: ethereum.enable(). Calling this method triggers a user interface that allows the user to approve or reject account access for a given dapp. This method returns a Promise that is resolved with an Array of accounts if the user approves access or rejected with an Error if the user rejects access.
[1] REQUESTDapps MUST request accounts by calling the eth_requestAccounts RPC method on the provider exposed at window.ethereum. Calling this method MAY trigger a user interface that allows the user to approve or reject account access for a given dapp. This method MUST return a Promise that is resolved with an array of one or more user accounts or rejected if no accounts are available (e.g., the user rejected account access).
[2] RESOLVEThe Promise returned when calling the eth_requestAccounts RPC method MUST be resolved with an Array of user accounts.
[3] REJECTThe Promise returned when calling the eth_requestAccounts RPC method MUST be rejected with an informative Error if no accounts are available for any reason.
window.ethereum .eth_requestAccounts RPC method.eth_requestAccounts promise.eth_requestAccounts promise is resolved.The pattern of automatic account exposure followed by the previous generation of Ethereum-enabled DOM environments fails to protect user privacy and fails to maintain safe user experience: untrusted websites can both view detailed account information and arbitrarily initiate transactions on a user's behalf. Even though most users may reject unsolicited transactions on untrusted websites, a protocol for account access should make such unsolicited requests impossible.
This proposal establishes a new pattern wherein dapps must request access to user accounts. This protocol directly strengthens user privacy by allowing the browser to hide user accounts and preventing unsolicited transaction requests on untrusted sites.
This proposal impacts dapp developers and requires that they request access to user accounts following the protocol outlined above. Similarly, this proposal impacts dapp browser developers and requires that they only expose user accounts following the protocol defined above.
The MetaMask team has implemented the strategy described above.
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