Calypso [1] offers a mean to store secrets on the blockchain. It uses a distributed keypair, where anyone can fetch and use the public key to encrypt a secret, but the private key is owned by the group of participating nodes. An encrypted secret is only revealed to the owner, or someone the owner authorized. When Alice wants to store her secret, she encrypts it with the distributed public key and stores it by executing a smart contract.
Upon execution, the smart contract storing the encrypted secret must check that Alice knows the secret, based solely on the encrypted secret it receives. Otherwise, an adversary Eve could perform a replay attack by copying over the ciphertext and faking a new access control policy.
For more information, please refer to the appendix of https://eprint.iacr.org/2018/209.pdf, the sections on Write Transaction Protocol for Long Term Secrets and D.1 Replay attack.
Go implementation is available at: https://github.com/dedis/cothority/blob/b80515bba800ad738ff79686bd2abfd2822e77d1/calypso/struct.go#L73