Add pwhash_SALTBYTES/0

src/enacl.erl

@@ -116,6 +116,7 @@
          shorthash_size/0,
          shorthash/2,
 
+         pwhash_SALTBYTES/0,
          pwhash/4,
          pwhash_str/3,
 
@@ -395,6 +396,13 @@ generichash_final(State) ->
     enacl_nif:crypto_generichash_final(State).
 
 -type pwhash_limit() :: interactive | moderate | sensitive | pos_integer().
+
+%% @doc pwhash_SALTBYTES/0 returns the number of bytes required for salt.
+%% @end
+-spec pwhash_SALTBYTES() -> pos_integer().
+pwhash_SALTBYTES() ->
+    enacl_nif:crypto_pwhash_SALTBYTES().
+
 %% @doc pwhash/2 hash a password
 %%
 %% This function generates a fixed size salted hash of a user defined password.

src/enacl_nif.erl

@@ -147,6 +147,7 @@
 
 %% Password Hashing - Argon2 Algorithm
 -export([
+         crypto_pwhash_SALTBYTES/0,
          crypto_pwhash/4,
          crypto_pwhash_str/3,
          crypto_pwhash_str_verify/2
@@ -238,6 +239,7 @@ crypto_secretstream_xchacha20poly1305_init_pull(_Header, _Key) -> erlang:nif_err
 crypto_secretstream_xchacha20poly1305_pull(_Ref, _CipherText, _AD) -> erlang:nif_error(nif_not_loaded).
 crypto_secretstream_xchacha20poly1305_rekey(_Ref) -> erlang:nif_error(nif_not_loaded).
 
+crypto_pwhash_SALTBYTES() -> erlang:nif_error(nif_not_loaded).
 crypto_pwhash(_Password, _Salt, _Ops, _Mem) -> erlang:nif_error(nif_not_loaded).
 crypto_pwhash_str(_Password, _Ops, _Mem) -> erlang:nif_error(nif_not_loaded).
 crypto_pwhash_str_verify(_HashedPassword, _Password) -> erlang:nif_error(nif_not_loaded).