...this is the standard way to sign messages in bitcoin-qt. Note that the
format of a compressed signature, for messages, is quite distinct from DER
format, which is used in transactions. This commit also adds support for
recovering the public key from a signature, which is necessary for this. The
code for public key recover is taken from bitcoinjs-lib.
This adds a new Message class with static methods for signing and verifying a
message the same way as bitcoind. (In a nutshell, messages a prepended with
"Bitcoin Signed Message:" before being hashed and signed).
There is one important piece missing ... verifying a signature with an address,
and not a public key. I have not yet implemented this because the cryptography
interface of bitcore does not allow me to derive the public key from a
signature. This will need to be added before verifying from an address is
possible.
Ryan X. Charles
Linus Unnebäck
Manuel Araoz