From a Key Inside an HSM to a Signed Blockchain Transaction
Follow a transfer of 10 tokens to understand HSM key labels and handles, signing digests, Ethereum signature conversion, chain-specific inputs, and connection failures.
12 min read
Application Security
6 articlesApplication security design for authentication, authorization, secrets, and attack resistance
Newest first
- Signing and operating MPC wallets · Part 3
What Does an MPC Relay Server Know, and What Does It Forward?
Follow the sessions, participants, key versions, and HPKE protection of joint signing messages to understand where an MPC relay server's authority ends and wallet signing authority begins.
- Signing and operating MPC wallets · Part 2
Can an MPC Wallet Stay the Same When Its Participants Change?
Replacing one participant in a 2-of-3 wallet explains how key shares can be redistributed without reconstructing the private key, why the public key stays the same, and where BXB's recovery and storage updates fit into the process.
- Signing and operating MPC wallets · Part 1
How Is MPC Signing Different from Multiple Approvals?
A 2-of-3 wallet explains secret sharing, distributed key generation, and threshold ECDSA, followed by how joint signing becomes an EVM transaction in BXB.
- Account execution and gas sponsorship · Part 2
EIP-7702: How can an existing EOA execute code?
A two-transfer example explains EIP-7702 code delegation at an existing address, authorization signatures and execution permissions, and how delegation persists, changes, and is cleared.
How Safe Can a Six-Character Redeem Code Be?
Starting with one issuance and redemption, separating randomness, database uniqueness, and FF1, then examining guessing risk and executable examples for six-character codes.