Serialization into bits added. #3

Author: Ilias Khairullin

include/nil/crypto3/marshalling/algebra/processing/curve_element.hpp

@@ -125,7 +125,6 @@ namespace nil {
 
                 template<typename Endianness, typename Coordinates>
                 struct curve_element_writer<
-
                     Endianness,
                     typename algebra::curves::bls12_381::template g2_type<Coordinates,
                                                                           algebra::curves::forms::short_weierstrass>> {
@@ -175,7 +174,6 @@ namespace nil {
 
                 template<typename Coordinates>
                 struct curve_element_writer<
-
                     nil::marshalling::endian::little_endian,
                     typename algebra::curves::curve25519::template g1_type<Coordinates,
                                                                            algebra::curves::forms::twisted_edwards>> {
@@ -240,12 +238,26 @@ namespace nil {
                     /// https://zips.z.cash/protocol/protocol.pdf#concreteextractorjubjub
                     template<typename TIter>
                     static nil::marshalling::status_type process(const group_value_type &point, TIter &iter) {
-                       write_data<params_type::bit_length(), endianness>(
+                        write_data<params_type::bit_length(), endianness>(
                             static_cast<typename group_value_type::field_type::integral_type>(point.to_affine().X.data),
                             iter);
 
                         return nil::marshalling::status_type::success;
                     }
+
+                    // TODO: refactor
+                    template<>
+                    static nil::marshalling::status_type
+                        process<typename std::vector<bool>::iterator>(const group_value_type &point,
+                                                                      typename std::vector<bool>::iterator &iter) {
+                        auto X_affine = static_cast<typename group_value_type::field_type::integral_type>(point.to_affine().X.data);
+                        for (std::size_t i = 0; i < params_type::bit_length(); ++i) {
+                            *iter++ = bit_test(X_affine, 0);
+                            X_affine >>= 1;
+                        }
+
+                        return nil::marshalling::status_type::success;
+                    }
                 };
 
                 template<typename Endianness, typename Coordinates>

test/curve_element.cpp

@@ -187,6 +187,15 @@ BOOST_AUTO_TEST_CASE(curve_element_jubjub_g1) {
     for (auto i = 0; i < expected_bits.size(); ++i) {
         BOOST_CHECK(expected_bits[i] == ((cv[i / 8] >> (i % 8)) & 1));
     }
+
+    /// serialization into bits
+    std::vector<bool> cv_bits = nil::marshalling::unpack_bits<nil::marshalling::option::little_endian>(point, status);
+    auto it1 = expected_bits.begin();
+    auto it2 = cv_bits.begin();
+    while (it1 != expected_bits.end() && it2 != cv_bits.end()) {
+        BOOST_CHECK(*it1++ == *it2++);
+    }
+    BOOST_CHECK(cv_bits.size() == field_type::value_bits);
 }
 
 BOOST_AUTO_TEST_CASE(curve_element_curve25519_g1) {