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.

5 files changed, 31 insertions, 87 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})
diff --git a/src/ringct/rctOps.h b/src/ringct/rctOps.h
index c9f2e7a43..3f8f6955c 100644
--- a/src/ringct/rctOps.h
+++ b/src/ringct/rctOps.h
@@ -112,14 +112,10 @@ namespace rct {
 
     //does a * G where a is a scalar and G is the curve basepoint
     void scalarmultBase(key & aG, const key &a);
-    void scalarmultBase(key & aG, const key &a, hw::device &hwdev);
     key scalarmultBase(const key & a);
-    key scalarmultBase(const key & a, hw::device &hwdev);
     //does a * P where a is a scalar and P is an arbitrary point
     void scalarmultKey(key &aP, const key &P, const key &a);
-    void scalarmultKey(key &aP, const key &P, const key &a, hw::device &hwdev);
     key scalarmultKey(const key &P, const key &a);
-    key scalarmultKey(const key &P, const key &a, hw::device &hwdev);
     //Computes aH where H= toPoint(cn_fast_hash(G)), G the basepoint
     key scalarmultH(const key & a);
 
@@ -178,8 +174,6 @@ namespace rct {
     //Elliptic Curve Diffie Helman: encodes and decodes the amount b and mask a
     // where C= aG + bH
     void ecdhEncode(ecdhTuple & unmasked, const key & sharedSec);
-    void ecdhEncode(ecdhTuple & unmasked, const key & sharedSec, hw::device &hwdev);
     void ecdhDecode(ecdhTuple & masked, const key & sharedSec);
-    void ecdhDecode(ecdhTuple & masked, const key & sharedSec, hw::device &hwdev);
 }
 #endif  /* RCTOPS_H */
diff --git a/src/ringct/rctOps_device.cpp b/src/ringct/rctOps_device.cpp
deleted file mode 100644
index fbfe8e9cf..000000000
--- a/src/ringct/rctOps_device.cpp
+++ /dev/null
@@ -1,66 +0,0 @@
-// Copyright (c) 2017-2018, The Monero Project
-// 
-// All rights reserved.
-// 
-// Redistribution and use in source and binary forms, with or without modification, are
-// permitted provided that the following conditions are met:
-// 
-// 1. Redistributions of source code must retain the above copyright notice, this list of
-//    conditions and the following disclaimer.
-// 
-// 2. Redistributions in binary form must reproduce the above copyright notice, this list
-//    of conditions and the following disclaimer in the documentation and/or other
-//    materials provided with the distribution.
-// 
-// 3. Neither the name of the copyright holder nor the names of its contributors may be
-//    used to endorse or promote products derived from this software without specific
-//    prior written permission.
-// 
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
-// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
-// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
-// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
-// 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 "misc_log_ex.h"
-#include "rctOps.h"
-#include "device/device.hpp"
-using namespace crypto;
-using namespace std;
-
-
-namespace rct
-{
-    void scalarmultKey(key & aP, const key &P, const key &a, hw::device &hwdev) {
-        hwdev.scalarmultKey(aP, P, a);
-    }
-
-    key scalarmultKey(const key & P, const key & a, hw::device &hwdev) {
-        key aP;
-        hwdev.scalarmultKey(aP, P, a);
-        return aP;
-    }
-
-    void scalarmultBase(key &aG, const key &a, hw::device &hwdev) {
-        hwdev.scalarmultBase(aG, a);
-    }
-
-    key scalarmultBase(const key & a, hw::device &hwdev) {
-        key aG;
-        hwdev.scalarmultBase(aG, a);
-        return aG;
-    }
-
-    void ecdhDecode(ecdhTuple & masked, const key & sharedSec, hw::device &hwdev) {
-        hwdev.ecdhDecode(masked, sharedSec);
-    }
-
-    void ecdhEncode(ecdhTuple & unmasked, const key & sharedSec, hw::device &hwdev) {
-        hwdev.ecdhEncode(unmasked, sharedSec);
-    }
-}
\ No newline at end of file
diff --git a/src/ringct/rctSigs.cpp b/src/ringct/rctSigs.cpp
index ae0ee21c8..f1f2f85a5 100644
--- a/src/ringct/rctSigs.cpp
+++ b/src/ringct/rctSigs.cpp
@@ -35,9 +35,6 @@
 #include "rctSigs.h"
 #include "bulletproofs.h"
 #include "cryptonote_basic/cryptonote_format_utils.h"
-#include "cryptonote_basic/cryptonote_basic.h"
-#include "cryptonote_basic/subaddress_index.h"
-#include "device/device.hpp"
 
 using namespace crypto;
 using namespace std;
@@ -669,7 +666,7 @@ namespace rct {
             //mask amount and mask
             rv.ecdhInfo[i].mask = copy(outSk[i].mask);
             rv.ecdhInfo[i].amount = d2h(amounts[i]);
-            ecdhEncode(rv.ecdhInfo[i], amount_keys[i], hwdev);
+            hwdev.ecdhEncode(rv.ecdhInfo[i], amount_keys[i]);
         }
 
         //set txn fee
@@ -750,7 +747,7 @@ namespace rct {
             //mask amount and mask
             rv.ecdhInfo[i].mask = copy(outSk[i].mask);
             rv.ecdhInfo[i].amount = d2h(outamounts[i]);
-            ecdhEncode(rv.ecdhInfo[i], amount_keys[i],hwdev);
+            hwdev.ecdhEncode(rv.ecdhInfo[i], amount_keys[i]);
         }
             
         //set txn fee
@@ -1007,7 +1004,7 @@ namespace rct {
 
         //mask amount and mask
         ecdhTuple ecdh_info = rv.ecdhInfo[i];
-        ecdhDecode(ecdh_info, sk, hwdev);
+        hwdev.ecdhDecode(ecdh_info, sk);
         mask = ecdh_info.mask;
         key amount = ecdh_info.amount;
         key C = rv.outPk[i].mask;
@@ -1035,7 +1032,7 @@ namespace rct {
 
         //mask amount and mask
         ecdhTuple ecdh_info = rv.ecdhInfo[i];
-        ecdhDecode(ecdh_info, sk, hwdev);
+        hwdev.ecdhDecode(ecdh_info, sk);
         mask = ecdh_info.mask;
         key amount = ecdh_info.amount;
         key C = rv.outPk[i].mask;
diff --git a/src/ringct/rctSigs.h b/src/ringct/rctSigs.h
index 7485938ee..b8aab0f11 100644
--- a/src/ringct/rctSigs.h
+++ b/src/ringct/rctSigs.h
@@ -50,8 +50,6 @@ extern "C" {
 
 #include "rctTypes.h"
 #include "rctOps.h"
-#include "cryptonote_basic/cryptonote_basic.h"
-#include "device/device_declare.hpp"
 
 //Define this flag when debugging to get additional info on the console
 #ifdef DBG
@@ -60,6 +58,9 @@ extern "C" {
 #define DP(x)
 #endif
 
+namespace hw {
+    class device;
+}
 
 
 namespace rct {