Glacier is a protocol for secure cold storage of bitcoins. https://glacierprotocol.org
You are right. Thanks. I just successfully completed a test deposit and withdrawal on Q1. (Yes, I processed the transaction without confirming on Q2, but it was a small test amount, and I know not to do this with larger sums). Now I just need to make sure the raw signed transaction matches for Q2 after I finish the process on that computer. I doubt I would have gotten this far without your help. Thanks for helping me out.
the first six characters were the same for both script. The last four characters were the same for both script.
You can run
bitcoin-cli decodescript (or something like that?) to convert the hex redeem script back to opcodes
The four pubkeys in the script will be different between your two wallets. The rest will be the same.
It's not really addressed in the protocol, but after a successful test deposit and withdrawal have been made, and as long as the rest of the protocol has been executed properly, is it safe to assume that the wallet is ready for use? Or are there any other variations of deposit and withdrawal testing that should be (or could be) done?
You might want to do two test withdrawals: one using the first two keys, and a second using the other two keys.
You do not need to actually broadcast either of these test withdrawals; just make sure you see "Sufficient keys: True" or something like that at the end of GlacierScript's output.
"Sufficient private keys to execute transaction?" must be followed by True. Make sure you see this for both pairs of keys.
After that, if I were you, I'd make sure your private keys were sealed up and geographically distributed, and only then deposit any significant sum into your new wallet.
Just to clarify about the test withdrawals: you can use the same UTXOs you previously printed out (and already spent). You've already demonstrated that you can successfully broadcast a withdrawal transaction. All that's left to prove is that each of your 4 keys will work on this wallet.
How can a non-technical person be confident in any cold storage solution (glacier, Casa, hardware wallets) if they cannot audit the code for themselves? What steps can someone like me take to have maximum faith in Glacier and/or Casa? I know that I could take the time to learn to audit the code, but that would take more time than I have to make a decision about how to hodl most securely
The same problem applies to any Bitcoin wallet software, not just cold storage.
Or really, any software you ever install on your computer. People abusing that trust is what led to malware.
At the same time, any public maintainer is basically announcing to the world that he/she has a large sum of bitcoins. This is not wise.
As a result we have had several anonymous contributors but a dearth of public reviewers and maintainers.
concern about glacier is complexity when it comes to inheritance. I wrote a five page detailed letter to my loved ones already but still have concerns that they would be able to figure it out without contacting an outsider with technical ability.
I’m thinking I should use glacier and hope not to die before a better solution comes out
And provide an exceptional set of instructions to the best of my ability to my non-technical family
I also have concerns about inheritance. I've written a similar letter. One thing I've considered is developing and documenting a low-security withdrawal process for use if all else fails. Glacier is fairly straightforward single-address multisig. The complexity lies in doing it all securely, using the offline quarantined laptops.
I meant to say included in the protocol as an appendix or something
Part of it comes from trusting the review process of Glacier, but a big part comes from limiting the attack surface. If someone were able to compromise GlacierScript, there's not much they could do, since GlacierScript has no control over where its inputs come from, or where its outputs go to. After building a transaction with GlacierScript, you scan out the transaction and send it to coinb.in for validation and broadcast.
So in order for the attacker to extract any info, they would need to compromise both GlacierScript (at the time you build your APP USBs), and coinb.in (at the time you build your withdrawal).
Although -- there is one form of attack that might be possible, a "chosen nonce attack", where the signatures in the transaction can reveal a part of your private key. If the attacker could compromise GlacierScript to create such signatures, they could scan the blockchain for your withdrawals and possibly determine your private key. Since Glacier reuses addresses, this could be effective.
I don't think such an attack is possible IF you use an uncompromised Bitcoin Core for signing transactions. And GlacierScript does so, and it has been reviewed and audited by many people (including myself), so I am confident in its security.
Note: any wallet system will have the same kinds of attack vectors. In this regard, Glacier is better than any other system I'm aware of.
Good question. That comes from GlacierScript itself, specifically this code here: https://github.com/GlacierProtocol/GlacierProtocol/blob/bda9582eda7280f6b154d63eb1c5359ab76fe369/glacierscript.py#L635
Which, if compromised, could generate keys known to the attacker.
But in your view, have even the latest releases Of Glacier been reviewed thoroughly enough to support the idea that the code remains well-reviewed? I know many people reviewed and commented on earlier versions, but that enthusiasm from some of the other contributors dropped off over time. What would keep someone from slipping something malicious into the code now that not as many people are looking? Are all modifications to the code, however small, closely monitored?
You can look at the history of PRs to confirm this: https://github.com/GlacierProtocol/GlacierProtocol/pulls?q=is%3Apr+is%3Aclosed
For anyone who might have private keys stored in bank safe deposit boxes as part of their Glacier Protocol, here's something to consider - I was granted access to my safe deposit box yesterday while wearing a medical mask. I was never asked to remove the mask so that they could verify my identity. Granted, I did still have to show my ID and had to have the key to my box, but it was still a bit shocking. Any person with similar physical characteristics to me could have pulled this off if they had my ID and safe key. This helped me understand that bank safe deposit boxes aren't as secure as I once believed them to be.
I have tested GlacierScript with Bitcoin Core v0.20.0rc2 (upcoming release). No changes needed. (Although, thanks to bug #38, Glacier is broken anyway, and nobody seems to care.)