Enhancing Bitcoin Transactions with Covenants

  • Russell O’ConnorEmail author
  • Marta Piekarska
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10323)


Covenants are Bitcoin Script programs that restrict how funds are allowed to be spent. In previous work [9], Möser et al. implemented covenants with a new Script operation that allows one to programmatically query the transaction. In this paper, we show that covenants can be implemented with a new CHECKSIGFROMSTACK operation that verifies a signature for a message passed as an argument. When the same public key and signature is used together with CHECKSIG, one can recover transaction data, which then allows one to enforce a covenant. To illustrate our technique, we reimplement Möser et al.’s vault construction for securing funds against key compromise. We use Elements Alpha, a sidechain whose Script language has the needed operations.


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Copyright information

© International Financial Cryptography Association 2017

Authors and Affiliations

  1. 1.BlockstreamMontréalCanada

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