ringct & cryptonote_basic: detangle dependencies

`libringct` was linking against `libcryptonote_basic` for a single, one-line convenience function: `cryptonote::get_blob_hash`.
Since `cryptonote_basic.h` includes `rctTypes.h`, this one function effectively made an explicit circular dependency between
the two libraries. `cryptonote_format_utils.cpp` was including header `rctSigs.h` from `libringct`, when only `rctOps.h` from
`libringct_basic` needed to be included. `libcryptonote_basic` wasn't explictly linking against `libringct_basic` nor
`libringct` like it should have. And `libblockchain_db` wasn't linking against `libcryptonote_basic` like it should have. We
can also downgrade `libblockchain_db`'s dependency on `libringct` to `libringct_basic`.

src/blockchain_db/CMakeLists.txt

@@ -45,7 +45,8 @@ target_link_libraries(blockchain_db
   PUBLIC
     common
     cncrypto
-    ringct
+    cryptonote_basic
+    ringct_basic
     ${LMDB_LIBRARY}
     ${Boost_FILESYSTEM_LIBRARY}
     ${Boost_THREAD_LIBRARY}

src/cryptonote_basic/CMakeLists.txt

@@ -71,6 +71,7 @@ target_link_libraries(cryptonote_basic
     checkpoints
     cryptonote_format_utils_basic
     device
+    ringct_basic
     ${Boost_DATE_TIME_LIBRARY}
     ${Boost_PROGRAM_OPTIONS_LIBRARY}
     ${Boost_SERIALIZATION_LIBRARY}

src/cryptonote_basic/cryptonote_format_utils.cpp

@@ -38,7 +38,7 @@
 #include "cryptonote_config.h"
 #include "crypto/crypto.h"
 #include "crypto/hash.h"
-#include "ringct/rctSigs.h"
+#include "ringct/rctOps.h"
 
 using namespace epee;
 

src/ringct/CMakeLists.txt

@@ -69,7 +69,6 @@ target_link_libraries(ringct
   PUBLIC
     common
     cncrypto
-    cryptonote_basic
     device
   PRIVATE
     ${OPENSSL_LIBRARIES}

src/ringct/rctSigs.cpp

@@ -28,16 +28,18 @@
 // 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 "rctSigs.h"
+
 #include "misc_log_ex.h"
 #include "misc_language.h"
 #include "common/perf_timer.h"
 #include "common/threadpool.h"
 #include "common/util.h"
-#include "rctSigs.h"
 #include "bulletproofs.h"
 #include "bulletproofs_plus.h"
-#include "cryptonote_basic/cryptonote_format_utils.h"
 #include "cryptonote_config.h"
+#include "device/device.hpp"
+#include "serialization/crypto.h"
 
 using namespace crypto;
 using namespace std;
@@ -612,7 +614,8 @@ namespace rct {
       key prehash;
       CHECK_AND_ASSERT_THROW_MES(const_cast<rctSig&>(rv).serialize_rctsig_base(ba, inputs, outputs),
           "Failed to serialize rctSigBase");
-      cryptonote::get_blob_hash(ss.str(), h);
+      const std::string sig_base_blob = ss.str();
+      cn_fast_hash(sig_base_blob.data(), sig_base_blob.size(), h);
       hashes.push_back(hash2rct(h));
 
       keyV kv;