Add keccak-512 to host functions. (paritytech#7531)

Author: tomusdrw

primitives/core/src/hashing.rs

@@ -16,6 +16,11 @@
 // limitations under the License.
 
 //! Hashing functions.
+//!
+//! This module is gated by `full-crypto` feature. If you intend to use any of the functions
+//! defined here within your runtime, you should most likely rather use [sp_io::hashing] instead,
+//! unless you know what you're doing. Using `sp_io` will be more performant, since instead of
+//! computing the hash in WASM it delegates that computation to the host client.
 
 use blake2_rfc;
 use sha2::{Digest, Sha256};

primitives/io/src/lib.rs

@@ -735,6 +735,11 @@ pub trait Hashing {
 		sp_core::hashing::keccak_256(data)
 	}
 
+	/// Conduct a 512-bit Keccak hash.
+	fn keccak_512(data: &[u8]) -> [u8; 64] {
+		sp_core::hashing::keccak_512(data)
+	}
+
 	/// Conduct a 256-bit Sha2 hash.
 	fn sha2_256(data: &[u8]) -> [u8; 32] {
 		sp_core::hashing::sha2_256(data)