Remove ringct dep in fcmp_pp, impl in fcmp_pp_crypto

src/fcmp_pp/CMakeLists.txt

@@ -28,6 +28,7 @@
 
 set(fcmp_pp_sources
   curve_trees.cpp
+  fcmp_pp_crypto.cpp
   tower_cycle.cpp)
 
 monero_find_all_headers(fcmp_pp_headers "${CMAKE_CURRENT_SOURCE_DIR}")
@@ -52,7 +53,6 @@ target_link_libraries(fcmp_pp
     cncrypto
     cryptonote_basic
     epee
-    ringct_basic
   PRIVATE
     ${CMAKE_CURRENT_BINARY_DIR}/fcmp_pp_rust/libfcmp_pp_rust.a
     ${EXTRA_LIBRARIES}

src/fcmp_pp/curve_trees.cpp

@@ -26,8 +26,10 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#include "cryptonote_basic/cryptonote_format_utils.h"
 #include "curve_trees.h"
+
+#include "cryptonote_basic/cryptonote_format_utils.h"
+#include "fcmp_pp_crypto.h"
 #include "ringct/rctOps.h"
 
 
@@ -705,9 +707,9 @@ CurveTrees<Helios, Selene>::LeafTuple CurveTrees<Helios, Selene>::leaf_tuple(
     const rct::key &commitment              = output_pair.commitment;
 
     rct::key O, C;
-    if (!rct::clear_torsion(rct::pk2rct(output_pubkey), O))
+    if (!fcmp_pp::clear_torsion(rct::pk2rct(output_pubkey), O))
         throw std::runtime_error("output pubkey is invalid");
-    if (!rct::clear_torsion(commitment, C))
+    if (!fcmp_pp::clear_torsion(commitment, C))
         throw std::runtime_error("commitment is invalid");
 
     if (O == rct::I)
@@ -722,11 +724,11 @@ CurveTrees<Helios, Selene>::LeafTuple CurveTrees<Helios, Selene>::leaf_tuple(
     crypto::derive_key_image_generator(output_pubkey, I);
 
     rct::key O_x, I_x, C_x;
-    if (!rct::point_to_wei_x(O, O_x))
+    if (!fcmp_pp::point_to_wei_x(O, O_x))
         throw std::runtime_error("failed to get wei x scalar from O");
-    if (!rct::point_to_wei_x(rct::pt2rct(I), I_x))
+    if (!fcmp_pp::point_to_wei_x(rct::pt2rct(I), I_x))
         throw std::runtime_error("failed to get wei x scalar from I");
-    if (!rct::point_to_wei_x(C, C_x))
+    if (!fcmp_pp::point_to_wei_x(C, C_x))
         throw std::runtime_error("failed to get wei x scalar from C");
 
     return LeafTuple{

src/ringct/rctOps.cpp

@@ -725,29 +725,4 @@ namespace rct {
           sc_sub(masked.amount.bytes, masked.amount.bytes, sharedSec2.bytes);
         }
     }
-
-    bool clear_torsion(const key &k, key &k_out) {
-        ge_p3 point;
-        if (ge_frombytes_vartime(&point, k.bytes) != 0)
-            return false;
-        // mul by inv 8, then mul by 8
-        ge_p2 point_inv_8;
-        ge_scalarmult(&point_inv_8, INV_EIGHT.bytes, &point);
-        ge_p1p1 point_inv_8_mul_8;
-        ge_mul8(&point_inv_8_mul_8, &point_inv_8);
-        ge_p3 torsion_cleared_point;
-        ge_p1p1_to_p3(&torsion_cleared_point, &point_inv_8_mul_8);
-        ge_p3_tobytes(k_out.bytes, &torsion_cleared_point);
-        return true;
-    }
-
-    bool point_to_wei_x(const key &pub, key &wei_x) {
-        if (pub == I)
-            return false;
-        fe y;
-        if (fe_frombytes_vartime(y, pub.bytes) != 0)
-            return false;
-        fe_ed_y_to_wei_x(wei_x.bytes, y);
-        return true;
-    }
 }

src/ringct/rctOps.h

@@ -188,9 +188,5 @@ namespace rct {
     key genCommitmentMask(const key &sk);
     void ecdhEncode(ecdhTuple & unmasked, const key & sharedSec, bool v2);
     void ecdhDecode(ecdhTuple & masked, const key & sharedSec, bool v2);
-
-    // TODO: tests for these functions specifically
-    bool clear_torsion(const key &k, key &k_out);
-    bool point_to_wei_x(const key &pub, key &wei_x);
 }
 #endif  /* RCTOPS_H */

tests/unit_tests/curve_trees.cpp

@@ -30,6 +30,7 @@
 
 #include "cryptonote_basic/cryptonote_format_utils.h"
 #include "curve_trees.h"
+#include "fcmp_pp/fcmp_pp_crypto.h"
 #include "misc_log_ex.h"
 #include "ringct/rctOps.h"
 #include "unit_tests_utils.h"
@@ -777,7 +778,7 @@ static const Selene::Scalar generate_random_selene_scalar()
     crypto::generate_keys(S, s, s, false);
 
     rct::key S_x;
-    CHECK_AND_ASSERT_THROW_MES(rct::point_to_wei_x(rct::pk2rct(S), S_x), "failed to convert to wei x");
+    CHECK_AND_ASSERT_THROW_MES(fcmp_pp::point_to_wei_x(rct::pk2rct(S), S_x), "failed to convert to wei x");
     return fcmp_pp::tower_cycle::selene_scalar_from_bytes(S_x);
 }
 //----------------------------------------------------------------------------------------------------------------------