Replace SHA3 with BLAKE2b everywhere

src/bin/grin.rs

@@ -21,7 +21,7 @@ extern crate log;
 extern crate env_logger;
 extern crate serde;
 extern crate serde_json;
-extern crate tiny_keccak;
+extern crate blake2;
 
 extern crate grin_api as api;
 extern crate grin_grin as grin;
@@ -34,8 +34,8 @@ use std::thread;
 use std::io::Read;
 use std::fs::File;
 use std::time::Duration;
-use tiny_keccak::Keccak;
 
+use blake2::blake2b::blake2b;
 use clap::{Arg, App, SubCommand, ArgMatches};
 use daemonize::Daemonize;
 
@@ -264,10 +264,7 @@ fn wallet_command(wallet_args: &ArgMatches) {
 	let hd_seed = wallet_args.value_of("pass").expect("Wallet passphrase required.");
 
 	// TODO do something closer to BIP39, eazy solution right now
-	let mut sha3 = Keccak::new_sha3_256();
-	sha3.update(hd_seed.as_bytes());
-	let mut seed = [0; 32];
-	sha3.finalize(&mut seed);
+  let seed = blake2b(32, &[], hd_seed.as_bytes());
 
 	let s = Secp256k1::new();
 	let key = wallet::ExtendedKey::from_seed(&s, &seed[..])