Public key to bitmessage address

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This page briefly describes, how to generate a Bitmessage Address from a public key. The variable after the list is used to refer to the step later

  1. Create a private and a public key for encryption and signing (resulting in 4 keys)
  2. Merge the public part of the signing key and the encryption key together. (encoded in uncompressed X9.62 format) (A)
  3. Take the SHA512 hash of A. (B)
  4. Take the RIPEMD160 of B. (C)
  5. Repeat step 1-4 until you have a result that starts with a zero (Or two zeros, if you want a short address). (D)
  6. Remove the zeros at the beginning of D. (E)
  7. Put the stream number (as a var_int) in front of E. (F)
  8. Put the address version (as a var_int) in front of F. (G)
  9. Take a double SHA512 (hash of a hash) of G and use the first four bytes as a checksum, that you append to the end. (H)
  10. base58 encode H. (J)
  11. Put "BM-" in front J. (K)

K is your full address

Note: Bitmessage's base58 encoding uses the following sequence (the same as Bitcoin's): "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz". Many existing libraries for base58 do not use this ordering.