▲ ▼ Secure transfer of encryption keys after death
The day before my surgery, which had high probability that I may not survive; I was setting up master key for my encryption keys, writing it to a physical file and handed it to my father telling him to hand it over to my company shareholders if the need arises and provided biometric access to my mother from my smartphone. Reason being, I was the single founder, executive of my startup, all the intangible assets was under my control and most of it encrypted as it should be.
So, incase of my demise I wanted my shareholders to have access to the data if they decide to run the company. Obviously I survived, but looking back at that day; I feel that if someone knew that they may die the next day they should probably do something better with their time than reminding their loved ones that they may die. Of-course, writing master key to a file is not great for security either.
For a non subjective example for this need gap, $145 million worth cryptocurrencies was locked after the CEO died and he was the only person with the passphrase for encryption.
Probably the best solution would be some kind of defi contract. In general, every will/trust has an executor, but you could build it in a trustless way if all you need to transfer are cryptographic keys. For example, you could write a de-fi contract that would automatically transfer the keys or all of your currency in three days to the wallets of your beneficiaries. If you survive the surgery, you would have 3 days to cancel the contracts execution.
I have a hands off approach towards cryptocurrencies so I didn't look in this direction but wouldn't the key be transparent to everyone on the blockchain and thereby defeating the purpose?
You would just encrypt the information and store it on on the chain. I believe defi contract languages have this functionality built in, but I’ve never written a contract myself.
Unless there's support for asymmetric encryption, this will not work as symmetric encryption would still require transfer of that key again. A quick search on Etherium's smart contract (solidity) results in it asymmetric encryption of smart contract data being impossible there.
Well all ledgers use asymmetric encryption on a fundamental level. I'm not an expert, so the following description is likely not entirely accurate, but it works something like this:
Every wallet is secured by a private key derived from a multi-word "recovery phrase". Your "wallet address" is derived from the private key and serves as the public key that anyone can use to verify that a transaction has, infact, come from your wallet. So at the very least, if you could guarantee the nonces/salts are sufficiently random, you could probably store arbitrary information in your wallet that only you could read.
I also know that smart contracts can be granted permission to make transactions on your behalf. In the simple case of needing to transfer crypto assets, for example, you could write a contract that could move all of your assets into and out of a trust.
All that said, I'm not sure if you could perfectly hand off arbitrary private key information completely on chain or not. Again - I'm not an expert. I'm not even a hobbiest. I'm just a spectator at this point.
Depending on where you live, you could store the password in a safety deposit box and then in your will specify who will become the owner of the safety deposit box on your death.
Gmail has a dead man's switch where another person becomes the owner of your account if you haven't logged in for x years. You could store your password in that account and log in every once in a while. Of course, Gmail would know your password now.
You could also split your encryption key into n pieces and give each numbered piece to someone you trust. While it is still possible they could access your account while living, they'd all have to cooperate to get your account.
All of them are good suggestions, but I feel cryptographic trust needs to be maintained in a solution for exchanging encryption keys especially since Alice is dead and Bob should be whom he claims to be but verified by the system.
Password manager - bitwardern has introduced 'Emergency Access' - https://bitwarden.com/help/article/emergency-access/ which can allow a trusted contact gain access to the vault data in case of emergency.