Fix AEAD parameter order / naming.

The order of parameters were in the wrong order. Make them equal
to the official order of libsodium.

While here, rename NONCEBYTES to NPUBBYTES so it reflects the
underlying names as well.

c_src/aead.c

@@ -41,13 +41,13 @@ enacl_crypto_aead_chacha20poly1305_encrypt(ErlNifEnv *env, int argc,
 
   if (argc != 4)
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[0], &key))
+  if (!enif_inspect_binary(env, argv[0], &message))
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[1], &nonce))
+  if (!enif_inspect_binary(env, argv[1], &ad))
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[2], &ad))
+  if (!enif_inspect_binary(env, argv[2], &nonce))
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[3], &message))
+  if (!enif_inspect_binary(env, argv[3], &key))
     goto bad_arg;
   if (key.size != crypto_aead_chacha20poly1305_ietf_KEYBYTES)
     goto bad_arg;
@@ -87,13 +87,13 @@ enacl_crypto_aead_chacha20poly1305_decrypt(ErlNifEnv *env, int argc,
 
   if (argc != 4)
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[0], &key))
+  if (!enif_inspect_binary(env, argv[0], &ciphertext))
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[1], &nonce))
+  if (!enif_inspect_binary(env, argv[1], &ad))
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[2], &ad))
+  if (!enif_inspect_binary(env, argv[2], &nonce))
     goto bad_arg;
-  if (!enif_inspect_binary(env, argv[3], &ciphertext))
+  if (!enif_inspect_binary(env, argv[3], &message))
     goto bad_arg;
 
   if (ciphertext.size < crypto_aead_chacha20poly1305_ietf_ABYTES)

src/enacl.erl

@@ -69,7 +69,7 @@
          aead_chacha20poly1305_encrypt/4,
          aead_chacha20poly1305_decrypt/4,
          aead_chacha20poly1305_KEYBYTES/0,
-         aead_chacha20poly1305_NONCEBYTES/0,
+         aead_chacha20poly1305_NPUBBYTES/0,
          aead_chacha20poly1305_ABYTES/0,
          aead_chacha20poly1305_MESSAGEBYTES_MAX/0,
 
@@ -1169,28 +1169,26 @@ kx_secret_key_size() ->
 %% `AD' using `Key' and `Nonce'. Returns the encrypted message followed by
 %% `aead_chacha20poly1305_ABYTES/0' bytes of MAC.
 %% @end
--spec aead_chacha20poly1305_encrypt(Key, Nonce, AD, Msg) -> binary() | {error, term()}
+-spec aead_chacha20poly1305_encrypt(Msg, AD, Nonce, Key) -> binary() | {error, term()}
     when Key :: binary(),
-         Nonce :: pos_integer(),
+         Nonce :: binary(),
          AD :: binary(),
          Msg :: binary().
-aead_chacha20poly1305_encrypt(Key, Nonce, AD, Msg) ->
-    NonceBin = <<0:32, Nonce:64/little-unsigned-integer>>,
-    enacl_nif:crypto_aead_chacha20poly1305_encrypt(Key, NonceBin, AD, Msg).
+aead_chacha20poly1305_encrypt(Msg, AD, Nonce, Key) ->
+    enacl_nif:crypto_aead_chacha20poly1305_encrypt(Msg, AD, Nonce, Key).
 
 %% @doc aead_chacha20poly1305_decrypt/4 decrypts ciphertext `CT' with additional
 %% data `AD' using `Key' and `Nonce'. Note: `CipherText' should contain
 %% `aead_chacha20poly1305_ABYTES/0' bytes that is the MAC. Returns the decrypted
 %% message.
 %% @end
--spec aead_chacha20poly1305_decrypt(Key, Nonce, AD, CT) -> binary() | {error, term()}
+-spec aead_chacha20poly1305_decrypt(CT, AD, Nonce, Key) -> binary() | {error, term()}
     when Key :: binary(),
-         Nonce :: pos_integer(),
+         Nonce :: binary(),
          AD :: binary(),
          CT :: binary().
-aead_chacha20poly1305_decrypt(Key, Nonce, AD, CT) ->
-    NonceBin = <<0:32, Nonce:64/little-unsigned-integer>>,
-    enacl_nif:crypto_aead_chacha20poly1305_decrypt(Key, NonceBin, AD, CT).
+aead_chacha20poly1305_decrypt(CT, AD, Nonce, Key) ->
+    enacl_nif:crypto_aead_chacha20poly1305_decrypt(CT, AD, Nonce, Key).
 
 %% @doc aead_chacha20poly1305_KEYBYTES/0 returns the number of bytes
 %% of the key used in AEAD ChaCha20 Poly1305 encryption/decryption.
@@ -1199,11 +1197,11 @@ aead_chacha20poly1305_decrypt(Key, Nonce, AD, CT) ->
 aead_chacha20poly1305_KEYBYTES() ->
     enacl_nif:crypto_aead_chacha20poly1305_KEYBYTES().
 
-%% @doc aead_chacha20poly1305_NONCEBYTES/0 returns the number of bytes
+%% @doc aead_chacha20poly1305_NPUBBYTES/0 returns the number of bytes
 %% of the Nonce in AEAD ChaCha20 Poly1305 encryption/decryption.
 %% @end
--spec aead_chacha20poly1305_NONCEBYTES() -> pos_integer().
-aead_chacha20poly1305_NONCEBYTES() ->
+-spec aead_chacha20poly1305_NPUBBYTES() -> pos_integer().
+aead_chacha20poly1305_NPUBBYTES() ->
     enacl_nif:crypto_aead_chacha20poly1305_NPUBBYTES().
 
 %% @doc aead_chacha20poly1305_ABYTES/0 returns the number of bytes

src/enacl_nif.erl

@@ -272,15 +272,15 @@ crypto_stream_b(_Bytes, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 crypto_stream_xor(_M, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 crypto_stream_xor_b(_M, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 
-crypto_aead_chacha20poly1305_encrypt(_Key, _Nonce, _AD, _Message) -> erlang:nif_error(nif_not_loaded).
-crypto_aead_chacha20poly1305_decrypt(_Key, _Nonce, _AD, _Message) -> erlang:nif_error(nif_not_loaded).
+crypto_aead_chacha20poly1305_encrypt(_Message, _AD, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
+crypto_aead_chacha20poly1305_decrypt(_CipherText, _AD, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 crypto_aead_chacha20poly1305_KEYBYTES()                           -> erlang:nif_error(nif_not_loaded).
 crypto_aead_chacha20poly1305_NPUBBYTES()                          -> erlang:nif_error(nif_not_loaded).
 crypto_aead_chacha20poly1305_ABYTES()                             -> erlang:nif_error(nif_not_loaded).
 crypto_aead_chacha20poly1305_MESSAGEBYTES_MAX()                   -> erlang:nif_error(nif_not_loaded).
 
-crypto_aead_xchacha20poly1305_encrypt(_Key, _Nonce, _AD, _Message) -> erlang:nif_error(nif_not_loaded).
-crypto_aead_xchacha20poly1305_decrypt(_Key, _Nonce, _AD, _Message) -> erlang:nif_error(nif_not_loaded).
+crypto_aead_xchacha20poly1305_encrypt(_Message, _AD, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
+crypto_aead_xchacha20poly1305_decrypt(_CipherText, _AD, _Nonce, _Key) -> erlang:nif_error(nif_not_loaded).
 crypto_aead_xchacha20poly1305_KEYBYTES()                           -> erlang:nif_error(nif_not_loaded).
 crypto_aead_xchacha20poly1305_NPUBBYTES()                          -> erlang:nif_error(nif_not_loaded).
 crypto_aead_xchacha20poly1305_ABYTES()                             -> erlang:nif_error(nif_not_loaded).

test/enacl_SUITE.erl

@@ -103,14 +103,15 @@ aead_xchacha20poly1305(_Config) ->
     ok.
 
 aead_chacha20poly1305(_Config) ->
+    NonceLen = enacl:aead_chacha20poly1305_NPUBBYTES(),
     KLen = enacl:aead_chacha20poly1305_KEYBYTES(),
     Key = binary:copy(<<"K">>, KLen),
     Msg = <<"test">>,
     AD = <<1,2,3,4,5,6>>,
-    Nonce = 1337,
+    Nonce = binary:copy(<<"N">>, NonceLen),
 
-    CipherText = enacl:aead_chacha20poly1305_encrypt(Key, Nonce, AD, Msg),
-    Msg = enacl:aead_chacha20poly1305_decrypt(Key, Nonce, AD, CipherText),
+    CipherText = enacl:aead_chacha20poly1305_encrypt(Msg, AD, Nonce, Key),
+    Msg = enacl:aead_chacha20poly1305_decrypt(CipherText, AD, Nonce, Key),
     ok.
 
 pwhash(_Config) ->