Author: Jonathan Underwood 2019-06-27 09:52:28
Published on: 2019-06-27T09:52:28+00:00
The proposed key value specification aims to address the issue of verifying addresses when transferring funds from cold to warm and warm to hot wallets. While BIP32_DERIVATION can verify an address from a specific XPUB, it cannot verify its signature. The solution involves securely verifying the xpub of the warm/hot wallet, signing the xpub with all cold keys using an airgap signing tool, uploading the signature/xpub pairs to the online unsigned transaction generator, and including one keyval pair per coldkey/xpub pairing.To avoid complicating the core PSBT specification, it is suggested that the numerous possible schemes should be dealt with outside of PSBT as 'PSBT metainformation', or using some form of 'vendor-specific', or 'metainformation-specific' PSBT field. This approach would make implementing PSBT for simple cases easier because the core specification would not grow too big.When signing offline, the wallet must ensure that all outputs have BIP32_DERIVATION, and it can verify the outputs through the derivation, to the xpub, and to the signature, if the global keyval XPUB_SIGNATURE, with its pubkey in the key, is detected. Jonathan Underwood, Chief Bitcoin Officer of Bitbank Co., Ltd., authored this proposal to address these issues. He welcomes feedback on his proposal and provides a public key for encrypted messages.
Updated on: 2023-06-13T19:37:03.938901+00:00