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>How would you even know it was a bitcoin wallet address vs. something else? The fact you talk about doing that sort of thing would be a big clue. The benefit

>How would you even know it was a bitcoin wallet address vs. something else? The fact you talk about doing that sort of thing would be a big clue. The benefit of using proper symmetric encryption (like GPG, or even better, age[0]) is that even if you talk about or even fully explain your process, then it's still secure as long as you don't post your key. [0] https://age-encryption.org/ https://age-encryption.org/

umvi 6y ago
If you use "proper symmetric encryption" you have the same problem as before: how to smuggle the key over the border assuming they will search your person and online accounts ...?
- AgentME 6y ago
  Oh sorry, I think I'd lost that bit of context. This scenario of hiding a password during inspection is probably the main place where "security through obscurity" has validity. A big benefit of encrypting your cryptocurrency private key with a password and then hiding/obscuring that password instead of the raw private key itself is that good encryption will apply key-stretching to the password, making it harder to brute-force. If an attacker finds a random-looking value in your stuff, and believes that the value might be your bitcoin private key XORed by a short string, they it's very cheap for them to check whether each result is a valid bitcoin private key. There might even be structure in the bitcoin private key format that helps gives away the XOR key. But if they know your bitcoin private key (or something else) is encrypted by Age, and they find a random-looking value that might be your password XORed by a short string, then because Age uses scrypt on the password, then it will take longer for them to verify each attempt against the ciphertext.
- ohazi 6y ago
  It's not difficult to memorize one reasonably good passphrase, and there are well-known key-stretching algorithms that are understood to provide however many bits you need of actual security from this passphrase. > Just shift all the digits of your key by some secret (but very simple) algorithm You are basically suggesting that people roll their own crypto here. Or pseudo-crypto, or stego, or whatever you want to call it. Don't tell people to "Just do X" when the ambiguity in the methods that you describe leave >90% odds that the result of their work won't even pass a statistical uniformity test. This leaks the key. Once your adversary realizes that you made some sort of mistake here, they can write software to make their attack orders of magnitude easier than it would otherwise be.
  - umvi 6y ago
    > Once your adversary realizes that you made some sort of mistake here, they can write software to "Writing software" takes time, and by then all the money in the wallet would be gone
    - ohazi 6y ago
      While you're in a gulag? I don't understand why you're doubling down on this. There's an easy, correct way to do this that doesn't have the same vulnerabilities as the method you're describing. The tools to do this already exist. Don't XOR your fucking key bits into a jpeg... it's more work, and the probability of doing it wrong is super high. You're just asking for trouble here.
      - umvi 6y ago
        > While you're in a gulag? Well if you are in a gulag, your Bitcoins should be the least of your concerns. > There's an easy, correct way to do this that doesn't have the same vulnerabilities as the method you're describing Sorry, but I don't believe you. What is this "easy, correct" way of smuggling your bitcoins over the border that a) won't raise suspicion and get you thrown into a gulag b) doesn't require you to memorize the entire private key? Do whatever you want, you have to add obscurity layer(s) to the scheme at some point. It doesn't matter if you are using perfect crypto if said crypto draws attention to you at the border. What are my chances of being caught if I (for example) encode the private key into several emails using a scheme only I know? Zero. I'm not saying this will work at scale for everyone, but it is 100% guaranteed to work for me.
        ohazi 6y ago
        Nobody in this thread is arguing that you shouldn't use obscurity. We're arguing that you shouldn't use obscurity ON THE KEY. MEMORIZE the key. Obscure the ciphertext. You cannot hide a key effectively using steganography. It's not strong enough. The probability of intercept is way higher than the probability of successfully brute-forcing the key or the memorized passphrase used to generate the key when using a strong key-stretching algorithm (not chains-of-hashes). But there's also no reason to hide the key, because key-stretching allows you to memorize a passphrase instead. > What are my chances of being caught if I (for example) encode the private key into several emails using a scheme only I know? Zero. A cryptographer would actually work out a number here. It's a small number, but it isn't zero. Given the insane degree of protection that strong cryptography can provide, it's quite possible that that low number is still orders of magnitude higher than it would be if you just memorized the damn passphrase. > 100% guaranteed to work for me. That's not how cryptography works. It's provably correct, or it's broken.

umvi 6y ago

If you use "proper symmetric encryption" you have the same problem as before: how to smuggle the key over the border assuming they will search your person and online accounts ...?

AgentME 6y ago
Oh sorry, I think I'd lost that bit of context. This scenario of hiding a password during inspection is probably the main place where "security through obscurity" has validity. A big benefit of encrypting your cryptocurrency private key with a password and then hiding/obscuring that password instead of the raw private key itself is that good encryption will apply key-stretching to the password, making it harder to brute-force. If an attacker finds a random-looking value in your stuff, and believes that the value might be your bitcoin private key XORed by a short string, they it's very cheap for them to check whether each result is a valid bitcoin private key. There might even be structure in the bitcoin private key format that helps gives away the XOR key. But if they know your bitcoin private key (or something else) is encrypted by Age, and they find a random-looking value that might be your password XORed by a short string, then because Age uses scrypt on the password, then it will take longer for them to verify each attempt against the ciphertext.
ohazi 6y ago
It's not difficult to memorize one reasonably good passphrase, and there are well-known key-stretching algorithms that are understood to provide however many bits you need of actual security from this passphrase. > Just shift all the digits of your key by some secret (but very simple) algorithm You are basically suggesting that people roll their own crypto here. Or pseudo-crypto, or stego, or whatever you want to call it. Don't tell people to "Just do X" when the ambiguity in the methods that you describe leave >90% odds that the result of their work won't even pass a statistical uniformity test. This leaks the key. Once your adversary realizes that you made some sort of mistake here, they can write software to make their attack orders of magnitude easier than it would otherwise be.
- umvi 6y ago
  > Once your adversary realizes that you made some sort of mistake here, they can write software to "Writing software" takes time, and by then all the money in the wallet would be gone
  - ohazi 6y ago
    While you're in a gulag? I don't understand why you're doubling down on this. There's an easy, correct way to do this that doesn't have the same vulnerabilities as the method you're describing. The tools to do this already exist. Don't XOR your fucking key bits into a jpeg... it's more work, and the probability of doing it wrong is super high. You're just asking for trouble here.
    - umvi 6y ago
      > While you're in a gulag? Well if you are in a gulag, your Bitcoins should be the least of your concerns. > There's an easy, correct way to do this that doesn't have the same vulnerabilities as the method you're describing Sorry, but I don't believe you. What is this "easy, correct" way of smuggling your bitcoins over the border that a) won't raise suspicion and get you thrown into a gulag b) doesn't require you to memorize the entire private key? Do whatever you want, you have to add obscurity layer(s) to the scheme at some point. It doesn't matter if you are using perfect crypto if said crypto draws attention to you at the border. What are my chances of being caught if I (for example) encode the private key into several emails using a scheme only I know? Zero. I'm not saying this will work at scale for everyone, but it is 100% guaranteed to work for me.
      - ohazi 6y ago
        Nobody in this thread is arguing that you shouldn't use obscurity. We're arguing that you shouldn't use obscurity ON THE KEY. MEMORIZE the key. Obscure the ciphertext. You cannot hide a key effectively using steganography. It's not strong enough. The probability of intercept is way higher than the probability of successfully brute-forcing the key or the memorized passphrase used to generate the key when using a strong key-stretching algorithm (not chains-of-hashes). But there's also no reason to hide the key, because key-stretching allows you to memorize a passphrase instead. > What are my chances of being caught if I (for example) encode the private key into several emails using a scheme only I know? Zero. A cryptographer would actually work out a number here. It's a small number, but it isn't zero. Given the insane degree of protection that strong cryptography can provide, it's quite possible that that low number is still orders of magnitude higher than it would be if you just memorized the damn passphrase. > 100% guaranteed to work for me. That's not how cryptography works. It's provably correct, or it's broken.