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Session Keys

Session keys let you delegate signing permissions under specific conditions to a temporary keypair. With session keys, your app can:
  • Allow users to interact without constant signature popups
  • Enable short-term delegated permissions
  • Automate transactions safely under defined rules
Particle Network supports session keys through both the AA SDKs and the Account Abstraction RPC.
Currently supported only on the Biconomy v2.0.0 smart account implementation. Other smart account types will throw errors.

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How It Works

The session key flow has two main parts:
  1. Create & register the session
    • Generate a temporary keypair (session key).
    • Define metadata (sessionKeyData) including:
      • Session key address (temporary public key)
      • Linked user address
      • Permission parameters (limits, scope, etc.)
    • Deploy or configure a sessionValidationModule contract to validate UserOps.
    • Register the session on-chain.
  2. Use the session key
    • UserOps can now be signed by the session key instead of the primary wallet.
    • The validation module ensures only authorized operations go through.
👉 Check out this demo repo for a practical example.

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API & SDK Methods

To work with session keys, use:
  • createSessions — create and register a new session
  • validateSession — validate that a UserOperation is authorized under the session
Both are available in:

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Example Validation Contract

Here’s an example sessionValidationModule contract that implements validateSessionUserOp:
Solidity
// SPDX-License-Identifier: MIT
pragma solidity 0.8.19;

import {UserOperation} from "@account-abstraction/contracts/interfaces/UserOperation.sol";

abstract contract ISessionValidationModule {
    // execute(address,uint256,bytes)
    bytes4 public constant EXECUTE_SELECTOR = 0xb61d27f6;
    // execute_ncC(address,uint256,bytes)
    bytes4 public constant EXECUTE_OPTIMIZED_SELECTOR = 0x0000189a;

    /**
     * @dev validates if the _op (UserOperation) matches the SessionKey permissions
     * and that _op has been signed by this SessionKey
     * @param _op User Operation to be validated.
     * @param _userOpHash Hash of the User Operation to be validated.
     * @param _sessionKeyData SessionKey data, that describes sessionKey permissions
     * @param _sessionKeySignature Signature over the the _userOpHash.
     * @return true if the _op is valid, false otherwise.
     */
    function validateSessionUserOp(
        UserOperation calldata _op,
        bytes32 _userOpHash,
        bytes calldata _sessionKeyData,
        bytes calldata _sessionKeySignature
    ) external virtual returns (bool);
}

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Tutorial Video

Session Keys in Particle Smart Wallet-as-a-Service