RFC_0014: DUBP Mnemonic

rfc/0014_Dubp_Mnemonic.md

+# DUBP Mnemonic
+
+This RFC describes the conventions for generating a DUBP keypair.
+
+As a summary:
+
+1. Generate a random mnemonic
+2. Using [scrypt] to generate the seed from the mnemonic
+3. Encrypt the seed in [DEWIF] format with a password or pin code.
+
+# 1. Generate a random mnemonic
+
+A mnemonic is a safety phrase designed to be easy to remember. This concept is defined in [BIP39].
+
+# 2. Generate the seed from the mnemonic
+
+The seed must be generated via [scrypt] with the following parameters.
+
+## password
+
+mnemonic phrase encoded in UTF-8 NFKD
+
+## salt
+
+Hash SHA256 of the string "dubp" + `mnemonic phrase`.
+
+Example:
+
+mnemonic: `tongue cute mail fossil great frozen same social weasel impact brush kind`
+
+hashed string: `dubptongue cute mail fossil great frozen same social weasel impact brush kind`
+
+salt: `0x13EB03436DD9374B554648237AEF473117FCB3D985FBC78B3C397BD3EAD9CFE6`
+
+WARNING: The salt must be the binary value of hash sha256. It must not be encoded in base16, we give here its representation in base16 only for practical readability reasons.
+
+## key lenght
+
+Sometimes called `dklen` in some libraries.
+
+Expected value: `32`.
+
+## N,r,p parameters
+
+N= 4096
+r= 16
+p= 1
+
+## Example
+
+mnemonic: `tongue cute mail fossil great frozen same social weasel impact brush kind`
+
+seed (base64): `qGdvpbP9lJe7ZG4ZUSyu33KFeAEs/KkshAp9gEI4ReY=`
+
+public key (base58): `732SSfuwjB7jkt9th1zerGhphs6nknaCBCTozxUcPWPU`
+
+# 3. Encrypt the seed in [DEWIF] format
+
+The seed must never be stored in clear on the utility machine.
+
+It is recommended to encrypt the seed in [DEWIF] format.
+
+The password used to encrypt the seed must be sufficiently robust and preferably randomly generated.
+
+[BIP39]: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki#Wordlist
+[scrypt]: https://tools.ietf.org/html/rfc7914.html
+[DEWIF]: https://git.duniter.org/nodes/common/doc/blob/dewif/rfc/0013_Duniter_Encrypted_Wallet_Import_Format.md