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«Take a hash like bcrypt, give it a random input, and hash it for a month. Use the final hash as the encryption key, and then release the encrypted file and the random input to all the world. The first person who wants to decrypt the file has no choice but to redo the trillion hashes in order to get the same encryption key you used.» - http://www.gwern.net/Self-decrypting files?2

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лохматая стереометрия, антигосударственные скриншоты, many such cases, and 3 other people liked this

«Nor can the general public (or the NSA) exploit the parallelism they have available, because each hash depends sensitively on the hash before it - the avalanche effect is a key property to cryptographic hashes. On the other hand, the person running this algorithm can run it in parallel.» · 9000

«One generates n random inputs (for n CPUs, presumably), and sets them hashing as before for however long one can spare. Then, one sets up a chain between the n results - the final hash of seed 1 is used to encrypt seed 2, the final hash of which was the encryption for seed 3, and so on. Then one releases the encrypted file, the n−1 encrypted seeds, and the first seed. Now the public has to hash the first seed for a month, and only then can it unlock the second seed, and start hashing that for a month, and so on … If one has a thousand CPUs handy, one can store up 3 years’ of computation-resistance in just a day.» · 9000

Смешно. Можно потратить месяц на изучение математики и криптографии. Это эффективнее. · DS

^ Что именно смешно? Где дыра в этой схеме или какая схема timed release очевидно лучше? · 9000