Add structured delegation signatures (#21)

* Bump enacl dependency

* Add serialization of delegation signature data

rebar.config

@@ -1,4 +1,4 @@
 {erl_opts, [debug_info]}.
 {deps, [ {base58, {git, "https://github.com/aeternity/erl-base58.git", {ref, "60a3356"}}}
-       , {enacl, {git, "https://github.com/aeternity/enacl.git",       {ref, "793ddb5"}}}
+       , {enacl, {git, "https://github.com/aeternity/enacl.git",       {ref, "67fceef"}}}
        ]}.

rebar.lock

@@ -0,0 +1,8 @@
+[{<<"base58">>,
+  {git,"https://github.com/aeternity/erl-base58.git",
+       {ref,"60a335668a60328a29f9731b67c4a0e9e3d50ab6"}},
+  0},
+ {<<"enacl">>,
+  {git,"https://github.com/aeternity/enacl.git",
+       {ref,"67fceef42c0d055570f2e67b571f8d1f8de2f204"}},
+  0}].

src/aeser_delegation.erl

@@ -0,0 +1,81 @@
+%%%-------------------------------------------------------------------
+%%% @copyright (C) 2023, Aeternity Anstalt
+%%% @doc
+%%% Serialization of delegation signatures
+%%% @end
+%%%-------------------------------------------------------------------
+-module(aeser_delegation).
+
+-export([ aens_preclaim_sig/3
+        , aens_name_sig/4
+        , aens_sig/3
+
+        , oracle_sig/3
+        , oracle_response_sig/3
+        ]).
+
+%% Delegation signatures are prefixed with a unique tag, ensuring not to
+%% collide with serialized transactions.
+-define(DELEGATION_TAG, 16#1a01).
+
+-define(TYPE_AENS, 1).
+-define(TYPE_AENS_NAME, 2).
+-define(TYPE_AENS_PRECLAIM, 3).
+-define(TYPE_ORACLE, 4).
+-define(TYPE_ORACLE_RESPONSE, 5).
+
+-define(VSN, 1).
+
+-type sig_data() :: binary().
+
+-spec aens_preclaim_sig(binary(), aeser_id:id(), aeser_id:id()) -> sig_data().
+aens_preclaim_sig(NetworkId, Account, Contract) ->
+    assert_id(account, Account),
+    assert_id(contract, Contract),
+    Template = [{account, id}, {contract, id}],
+    Fields   = [{account, Account}, {contract, Contract}],
+    serialize(?TYPE_AENS_PRECLAIM, NetworkId, Template, Fields).
+
+-spec aens_name_sig(binary(), aeser_id:id(), aeser_id:id(), aeser_id:id()) -> sig_data().
+aens_name_sig(NetworkId, Account, Name, Contract) ->
+    assert_id(account, Account),
+    assert_id(name, Name),
+    assert_id(contract, Contract),
+    Template = [{account, id}, {name, id}, {contract, id}],
+    Fields   = [{account, Account}, {name, Name}, {contract, Contract}],
+    serialize(?TYPE_AENS_NAME, NetworkId, Template, Fields).
+
+-spec aens_sig(binary(), aeser_id:id(), aeser_id:id()) -> sig_data().
+aens_sig(NetworkId, Account, Contract) ->
+    assert_id(account, Account),
+    assert_id(contract, Contract),
+    Template = [{account, id}, {contract, id}],
+    Fields   = [{account, Account}, {contract, Contract}],
+    serialize(?TYPE_AENS, NetworkId, Template, Fields).
+
+-spec oracle_sig(binary(), aeser_id:id(), aeser_id:id()) -> sig_data().
+oracle_sig(NetworkId, Account, Contract) ->
+    assert_id(account, Account),
+    assert_id(contract, Contract),
+    Template = [{account, id}, {contract, id}],
+    Fields   = [{account, Account}, {contract, Contract}],
+    serialize(?TYPE_ORACLE, NetworkId, Template, Fields).
+
+-spec oracle_response_sig(binary(), aeser_id:id(), aeser_id:id()) -> sig_data().
+oracle_response_sig(NetworkId, QueryId, Contract) ->
+    assert_id(oracle, QueryId),
+    assert_id(contract, Contract),
+    Template = [{query, id}, {contract, id}],
+    Fields   = [{query, QueryId}, {contract, Contract}],
+    serialize(?TYPE_ORACLE_RESPONSE, NetworkId, Template, Fields).
+
+%% ------------------------------------------------------------------------
+%% -- Internal functions
+%% ------------------------------------------------------------------------
+
+serialize(Type, NetworkId, Template, Fields) ->
+    Data = aeserialization:serialize(Type, ?VSN, Template, Fields),
+    <<?DELEGATION_TAG:16, NetworkId/binary, Data/binary>>.
+
+assert_id(Type, AeserId) ->
+    Type = aeser_id:specialize_type(AeserId).

test/aeser_delegation_tests.erl

@@ -0,0 +1,67 @@
+%%%-------------------------------------------------------------------
+%%% @copyright (C) 2023, Aeternity Anstalt
+%%%-------------------------------------------------------------------
+
+-module(aeser_delegation_tests).
+
+-include_lib("eunit/include/eunit.hrl").
+
+-define(TEST_MODULE, aeser_delegation).
+
+-define(ACCOUNT, aeser_id:create(account, <<1:256>>)).
+-define(CONTRACT, aeser_id:create(contract, <<2:256>>)).
+-define(NAME, aeser_id:create(name, <<3:256>>)).
+-define(ORACLE, aeser_id:create(oracle, <<3:256>>)).
+
+-define(NETWORK_ID, <<"my_fancy_network"/utf8>>).
+
+encode_correct_test_() ->
+    [{"Encode preclaim sig",
+      fun() ->
+          aeser_delegation:aens_preclaim_sig(?NETWORK_ID, ?ACCOUNT, ?CONTRACT)
+      end},
+     {"Encode name sig",
+      fun() ->
+          aeser_delegation:aens_name_sig(?NETWORK_ID, ?ACCOUNT, ?NAME, ?CONTRACT)
+      end},
+     {"Encode aens wildcard sig",
+      fun() ->
+          aeser_delegation:aens_sig(?NETWORK_ID, ?ACCOUNT, ?CONTRACT)
+      end},
+     {"Encode oracle sig",
+      fun() ->
+          aeser_delegation:oracle_sig(?NETWORK_ID, ?ACCOUNT, ?CONTRACT)
+      end},
+     {"Encode oracle response sig",
+      fun() ->
+          aeser_delegation:oracle_response_sig(?NETWORK_ID, ?ORACLE, ?CONTRACT)
+      end}
+    ].
+
+encode_fail_test_() ->
+    [{"Bad encoding preclaim sig",
+      fun() ->
+          ?assertError(_, aeser_delegation:aens_preclaim_sig(?NETWORK_ID, <<42:256>>, ?CONTRACT)),
+          ?assertError(_, aeser_delegation:aens_preclaim_sig(?NETWORK_ID, ?CONTRACT, ?ACCOUNT))
+      end},
+     {"Bad encoding name sig",
+      fun() ->
+          ?assertError(_, aeser_delegation:aens_name_sig(?NETWORK_ID, ?ACCOUNT, <<42:256>>, ?CONTRACT)),
+          ?assertError(_, aeser_delegation:aens_name_sig(?NETWORK_ID, ?NAME, ?ACCOUNT, ?CONTRACT))
+      end},
+     {"Bad encoding aens wildcard sig",
+      fun() ->
+          ?assertError(_, aeser_delegation:aens_sig(?NETWORK_ID, ?ACCOUNT, <<42:256>>)),
+          ?assertError(_, aeser_delegation:aens_sig(?NETWORK_ID, ?CONTRACT, ?CONTRACT))
+      end},
+     {"Bad encoding oracle sig",
+      fun() ->
+          ?assertError(_, aeser_delegation:oracle_sig(?NETWORK_ID, <<42:256>>, ?CONTRACT)),
+          ?assertError(_, aeser_delegation:oracle_sig(?NETWORK_ID, ?ACCOUNT, ?ACCOUNT))
+      end},
+     {"Bad encoding oracle response sig",
+      fun() ->
+          ?assertError(_, aeser_delegation:oracle_response_sig(?NETWORK_ID, <<42:256>>, ?CONTRACT)),
+          ?assertError(_, aeser_delegation:oracle_response_sig(?NETWORK_ID, ?ORACLE, ?ORACLE))
+      end}
+    ].