69 lines
1.3 KiB
ReStructuredText
69 lines
1.3 KiB
ReStructuredText
==================
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Encrypted LeaseSet
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==================
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.. meta::
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:author: zzz
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:created: 2016-01-11
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:thread: http://zzz.i2p/topics/2047
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:lastupdated: 2016-01-12
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:status: Draft
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.. contents::
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Introduction
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============
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Current encrypted LS is horrendous and insecure. I can say that, I designed and
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implemented it.
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Reasons:
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- AES CBC encrypted
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- Single AES key for everybody
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- Lease expirations still exposed
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- Encryption pubkey still exposed
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Goals
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=====
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- Make entire thing opaque
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- Keys for each recipient
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Strategy
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========
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Do like GPG/OpenPGP does. Asymmetrically encrypt a symmetric key for each
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recipient. Data is decrypted with that asymmetric key. See e.g. [RFC-4880-S5.1]_
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IF we can find an algo that's small and fast.
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LS2 contents
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------------
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- Destination
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- Published timestamp
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- Expiration
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- Flags
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- Length of data
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- Encrypted data
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- Signature
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Encrypted data could be prefixed with some enctype specifier, or not.
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Trick is finding an asymmetric encryption that's small and fast. ElGamal at 514
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bytes is a little painful here. We can do better.
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See e.g. http://security.stackexchange.com/questions/824...
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This works for small numbers of recipients (or actually, keys; you can still
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distribute keys to multiple people if you like).
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References
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==========
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.. [RFC-4880-S5.1]
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https://tools.ietf.org/html/rfc4880#section-5.1
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