device: untangle cyclic depenency

When #3303 was merged, a cyclic dependency chain was generated:

    libdevice <- libcncrypto <- libringct <- libdevice

This was because libdevice needs access to a set of basic crypto operations
implemented in libringct such as scalarmultBase(), while libringct also needs
access to abstracted crypto operations implemented in libdevice such as
ecdhEncode(). To untangle this cyclic dependency chain, this patch splits libringct
into libringct_basic and libringct, where the basic crypto ops previously in
libringct are moved into libringct_basic. The cyclic dependency is now resolved
thanks to this separation:

    libcncrypto <- libringct_basic <- libdevice <- libcryptonote_basic <- libringct

This eliminates the need for crypto_device.cpp and rctOps_device.cpp.

Also, many abstracted interfaces of hw::device such as encrypt_payment_id() and
get_subaddress_secret_key() were previously implemented in libcryptonote_basic
(cryptonote_format_utils.cpp) and were then called from hw::core::device_default,
which is odd because libdevice is supposed to be independent of libcryptonote_basic.
Therefore, those functions were moved to device_default.cpp.

1 files changed, 24 insertions, 6 deletions

diff --git a/src/ringct/CMakeLists.txt b/src/ringct/CMakeLists.txt
index 2d3ea5cf4..c8dcdca26 100644
--- a/src/ringct/CMakeLists.txt
+++ b/src/ringct/CMakeLists.txt
@@ -26,21 +26,39 @@
 # 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.
 
-set(ringct_sources
+set(ringct_basic_sources
   rctOps.cpp
-  rctOps_device.cpp
-  rctSigs.cpp
   rctTypes.cpp
   rctCryptoOps.c
   bulletproofs.cc)
 
+set(ringct_basic_private_headers
+  rctOps.h
+  rctTypes.h
+  bulletproofs.h)
+
+monero_private_headers(ringct_basic
+  ${crypto_private_headers})
+monero_add_library(ringct_basic
+  ${ringct_basic_sources}
+  ${ringct_basic_private_headers})
+target_link_libraries(ringct_basic
+  PUBLIC
+    common
+    cncrypto
+  PRIVATE
+    ${OPENSSL_LIBRARIES}
+    ${EXTRA_LIBRARIES})
+
+set(ringct_sources
+  rctSigs.cpp
+)
+
 set(ringct_headers)
 
 set(ringct_private_headers
-  rctOps.h
   rctSigs.h
-  rctTypes.h
-  bulletproofs.h)
+)
 
 monero_private_headers(ringct
   ${crypto_private_headers})