Code modifications to integrate Ledger HW device into monero-wallet-cli.

The basic approach it to delegate all sensitive data (master key, secret
ephemeral key, key derivation, ....) and related operations to the device.
As device has low memory, it does not keep itself the values
(except for view/spend keys) but once computed there are encrypted (with AES
are equivalent) and return back to monero-wallet-cli. When they need to be
manipulated by the device, they are decrypted on receive.

Moreover, using the client for storing the value in encrypted form limits
the modification in the client code. Those values are transfered from one
C-structure to another one as previously.

The code modification has been done with the wishes to be open to any
other hardware wallet. To achieve that a C++ class hw::Device has been
introduced. Two initial implementations are provided: the "default", which
remaps all calls to initial Monero code, and  the "Ledger", which delegates
all calls to Ledger device.

1 files changed, 164 insertions, 0 deletions

diff --git a/src/device/log.cpp b/src/device/log.cpp
new file mode 100644
index 000000000..103b2b3ba
--- /dev/null
+++ b/src/device/log.cpp
@@ -0,0 +1,164 @@
+// 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 "log.hpp"
+
+namespace hw {
+
+    #ifdef WITH_DEVICE_LEDGER    
+    namespace ledger {
+    
+    #undef MONERO_DEFAULT_LOG_CATEGORY
+    #define MONERO_DEFAULT_LOG_CATEGORY "device.ledger"
+
+    void buffer_to_str(char *to_buff,  size_t to_len, const char *buff, size_t len) {
+      CHECK_AND_ASSERT_THROW_MES(to_len > (len*2), "destination buffer too short. At least" << (len*2+1) << " bytes required");
+      for (size_t i=0; i<len; i++) {
+        sprintf(to_buff+2*i, "%.02x", (unsigned char)buff[i]);
+      }
+    }
+
+    void log_hexbuffer(std::string msg,  const char* buff, size_t len) {
+      char logstr[1025];
+      buffer_to_str(logstr, sizeof(logstr),  buff, len);
+      MDEBUG(msg<< ": " << logstr);
+    }
+
+    void log_message(std::string msg,  std::string info ) {
+      MDEBUG(msg << ": " << info);
+    }
+
+    #ifdef DEBUGLEDGER
+    extern crypto::secret_key viewkey;
+    extern crypto::secret_key spendkey;
+
+
+    void decrypt(char* buf, size_t len) {
+      #ifdef IODUMMYCRYPT
+      int i;
+      if (len == 32) {
+        //view key?
+        for (i = 0; i<32; i++) {
+          if (buf[i] != 0) break;
+        }
+        if (i == 32) {
+          memmove(buf, hw::ledger::viewkey.data, 32);
+          return;
+        }
+        //spend key?
+        for (i = 0; i<32; i++) {
+          if (buf[i] != (char)0xff) break;
+        }
+        if (i == 32) {
+          memmove(buf, hw::ledger::spendkey.data, 32);
+          return;
+        }
+      }
+      //std decrypt: XOR.55h
+      for (i = 0; i<len;i++) {
+          buf[i] ^= 0x55;
+        }
+      #endif
+    }
+
+    crypto::key_derivation decrypt(const crypto::key_derivation &derivation) {
+       crypto::key_derivation x = derivation;
+       decrypt(x.data, 32);
+       return x;
+    }
+
+    cryptonote::account_keys decrypt(const cryptonote::account_keys& keys) {
+       cryptonote::account_keys x = keys;
+       decrypt(x.m_view_secret_key.data, 32);
+       decrypt(x.m_spend_secret_key.data, 32);
+       return x;
+    }
+
+
+    crypto::secret_key decrypt(const crypto::secret_key &sec) {
+       crypto::secret_key  x = sec;
+       decrypt(x.data, 32);
+       return x;
+    }
+
+    rct::key  decrypt(const rct::key &sec)  {
+         rct::key  x = sec;
+       decrypt((char*)x.bytes, 32);
+       return x;
+    }
+
+    crypto::ec_scalar decrypt(const crypto::ec_scalar &res)  {
+       crypto::ec_scalar  x = res;
+       decrypt((char*)x.data, 32);
+       return x;
+    }
+
+    rct::keyV decrypt(const rct::keyV &keys) {
+        rct::keyV x ;
+        for (unsigned int j = 0; j<keys.size(); j++) {
+            x.push_back(decrypt(keys[j]));
+        }
+        return x;
+    }
+
+    static void check(std::string msg, std::string info, const char *h, const char *d, int len, bool crypted) {
+      char dd[32];
+      char logstr[128];
+
+      memmove(dd,d,len);
+      if (crypted) {
+        CHECK_AND_ASSERT_THROW_MES(len<=32, "encrypted data greater than 32");
+        decrypt(dd,len);
+      }
+
+      if (memcmp(h,dd,len)) {
+          log_message("ASSERT EQ FAIL",  msg + ": "+ info );
+          log_hexbuffer("    host  ", h, len);
+          log_hexbuffer("    device", dd, len);
+
+      } else {
+        buffer_to_str(logstr,  dd, len);
+        log_message("ASSERT EQ OK",  msg + ": "+ info + ": "+ std::string(logstr) );
+      }
+    }
+
+    void check32(std::string msg, std::string info, const char *h, const char *d, bool crypted) {
+      check(msg, info, h, d, 32, crypted);
+    }
+
+    void check8(std::string msg, std::string info, const char *h, const char *d, bool crypted) {
+      check(msg, info, h, d, 8, crypted);
+    }
+    #endif
+
+  }
+  #endif //WITH_DEVICE_LEDGER    
+
+}
\ No newline at end of file