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+#Security Specification
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+
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+This document is here to help define security flaws in a way that can be agreed upon.
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+
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+##Definitions
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+
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+* Reveal: To reveal a piece of content is to send over the wire that content or something from which
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+that content can be mathematically derived (not withstanding theoretical attacks
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+eg: Quantum Computers unless explicitly said otherwise)
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+
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+* Matching Keypair: In relation to an IPv6 address, a public and private key for which the first
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+16 bytes of the double-SHA-512 (the SHA-512 of the SHA-512) of the public key matches the IPv6
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+address.
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+
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+* Permanent Private Key: The key which is in the configuration file which defines the node's
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+identity.
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+
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+##Limitation of Scope
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+
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+This document applies to the current version (latest master branch) of cjdns compiled and running
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+on a Linux system using a version of GCC with no known security issues and running on an
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+x86 or amd64 processor. Older versions and git branches may be non-compliant with this
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+specification.
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+
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+##Integrity and Confidentiality
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+
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+1. It must not be possible to reveal the permanent private key or any temporary session private keys
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+to anyone.
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+
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+2. It must not be possible to reveal any temporary symmetrical session keys to anyone other than the
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+identity (permanent public key) with which the session has been established.
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+
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+3. It must not be possible to reveal the content of any packet with an fc00::/8 destination address
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+which enters cjdns through the TUN device, except revealing it to the holder(s) of the Matching
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+Keypair for that address.
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+
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+4. It must not be possible to receive any packet with an fc00::/8 source address unless the sender
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+is in possession of the Matching Keypair for that address and the content (not including fields in
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+the IPv6 header other than source and destination addresses) has not been altered en-route.
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+
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+5. It must not be possible to receive a packet which is part of an ESTABLISHED session of that
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+packet was already received before.
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+
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+6. If the permanent private key is compromised, any traffic which was sent during a previous
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+ESTABLISHED session which has since ended will not be compromised as a result.
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+
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+NOTE: Traffic may also be sent when a session is in HANDSHAKE state and for traffic sent while the
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+session is in HANDSHAKE state, 5 and 6 may be violated.
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+
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+7. In the event of a cryptographic break of Curve25519 ECDH (for example using the Shor attack with
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+a Quantum Computer) any cryptographic session which was initiated using a password will remain
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+as strong as a session which had been initiated using that password as a symmetrical key.
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+
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+
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Caleb James DeLisle