Introduce wrappers around CZCSpendingKey

src/base58.cpp

@@ -378,3 +378,18 @@ boost::optional<libzcash::PaymentAddress> DecodePaymentAddress(const std::string
         return boost::none;
     }
 }
+
+std::string EncodeSpendingKey(const libzcash::SpendingKey& zkey)
+{
+    return CZCSpendingKey(zkey).ToString();
+}
+
+boost::optional<libzcash::SpendingKey> DecodeSpendingKey(const std::string& str)
+{
+    CZCSpendingKey key(str);
+    try {
+        return key.Get();
+    } catch (const std::runtime_error&) {
+        return boost::none;
+    }
+}

src/base58.h

@@ -182,4 +182,7 @@ bool IsValidDestinationString(const std::string& str, const CChainParams& params
 std::string EncodePaymentAddress(const libzcash::PaymentAddress& zaddr);
 boost::optional<libzcash::PaymentAddress> DecodePaymentAddress(const std::string& str);
 
+std::string EncodeSpendingKey(const libzcash::SpendingKey& zkey);
+boost::optional<libzcash::SpendingKey> DecodeSpendingKey(const std::string& str);
+
 #endif // BITCOIN_BASE58_H

src/test/key_tests.cpp

@@ -190,14 +190,14 @@ BOOST_AUTO_TEST_CASE(zc_address_test)
     for (size_t i = 0; i < 1000; i++) {
         auto sk = SpendingKey::random();
         {
-            CZCSpendingKey spendingkey(sk);
-            string sk_string = spendingkey.ToString();
+            string sk_string = EncodeSpendingKey(sk);
 
             BOOST_CHECK(sk_string[0] == 'S');
             BOOST_CHECK(sk_string[1] == 'K');
 
-            CZCSpendingKey spendingkey2(sk_string);
-            SpendingKey sk2 = spendingkey2.Get();
+            auto spendingkey2 = DecodeSpendingKey(sk_string);
+            BOOST_ASSERT(static_cast<bool>(spendingkey2));
+            SpendingKey sk2 = *spendingkey2;
             BOOST_CHECK(sk.inner() == sk2.inner());
         }
         {

src/test/rpc_wallet_tests.cpp

@@ -415,7 +415,7 @@ BOOST_AUTO_TEST_CASE(rpc_wallet_z_exportwallet)
     BOOST_CHECK(pwalletMain->GetSpendingKey(addr, key));
 
     std::string s1 = EncodePaymentAddress(addr);
-    std::string s2 = CZCSpendingKey(key).ToString();
+    std::string s2 = EncodeSpendingKey(key);
 
     // There's no way to really delete a private key so we will read in the
     // exported wallet file and search for the spending key and payment address.
@@ -459,7 +459,7 @@ BOOST_AUTO_TEST_CASE(rpc_wallet_z_importwallet)
     auto testSpendingKey = libzcash::SpendingKey::random();
     auto testPaymentAddress = testSpendingKey.address();
     std::string testAddr = EncodePaymentAddress(testPaymentAddress);
-    std::string testKey = CZCSpendingKey(testSpendingKey).ToString();
+    std::string testKey = EncodeSpendingKey(testSpendingKey);
 
     // create test data using the random key
     std::string format_str = "# Wallet dump created by Zcash v0.11.2.0.z8-9155cc6-dirty (2016-08-11 11:37:00 -0700)\n"
@@ -503,8 +503,7 @@ BOOST_AUTO_TEST_CASE(rpc_wallet_z_importwallet)
     // Verify the spending key is the same as the test data
     libzcash::SpendingKey k;
     BOOST_CHECK(pwalletMain->GetSpendingKey(addr, k));
-    CZCSpendingKey spendingkey(k);
-    BOOST_CHECK_EQUAL(testKey, spendingkey.ToString());
+    BOOST_CHECK_EQUAL(testKey, EncodeSpendingKey(k));
 }
 
 
@@ -528,7 +527,7 @@ BOOST_AUTO_TEST_CASE(rpc_wallet_z_importexport)
 
     // error if invalid args
     auto sk = libzcash::SpendingKey::random();
-    std::string prefix = std::string("z_importkey ") + CZCSpendingKey(sk).ToString() + " yes ";
+    std::string prefix = std::string("z_importkey ") + EncodeSpendingKey(sk) + " yes ";
     BOOST_CHECK_THROW(CallRPC(prefix + "-1"), runtime_error);
     BOOST_CHECK_THROW(CallRPC(prefix + "2147483647"), runtime_error); // allowed, but > height of active chain tip
     BOOST_CHECK_THROW(CallRPC(prefix + "2147483648"), runtime_error); // not allowed, > int32 used for nHeight
@@ -545,7 +544,7 @@ BOOST_AUTO_TEST_CASE(rpc_wallet_z_importexport)
         auto testSpendingKey = libzcash::SpendingKey::random();
         auto testPaymentAddress = testSpendingKey.address();
         std::string testAddr = EncodePaymentAddress(testPaymentAddress);
-        std::string testKey = CZCSpendingKey(testSpendingKey).ToString();
+        std::string testKey = EncodeSpendingKey(testSpendingKey);
         BOOST_CHECK_NO_THROW(CallRPC(string("z_importkey ") + testKey));
         BOOST_CHECK_NO_THROW(retValue = CallRPC(string("z_exportkey ") + testAddr));
         BOOST_CHECK_EQUAL(retValue.get_str(), testKey);

src/wallet/rpcdump.cpp

@@ -295,9 +295,9 @@ UniValue importwallet_impl(const UniValue& params, bool fHelp, bool fImportZKeys
 
         // Let's see if the address is a valid Zcash spending key
         if (fImportZKeys) {
-            try {
-                CZCSpendingKey spendingkey(vstr[0]);
-                libzcash::SpendingKey key = spendingkey.Get();
+            auto spendingkey = DecodeSpendingKey(vstr[0]);
+            if (spendingkey) {
+                libzcash::SpendingKey key = *spendingkey;
                 libzcash::PaymentAddress addr = key.address();
                 if (pwalletMain->HaveSpendingKey(addr)) {
                     LogPrint("zrpc", "Skipping import of zaddr %s (key already present)\n", EncodePaymentAddress(addr));
@@ -313,9 +313,8 @@ UniValue importwallet_impl(const UniValue& params, bool fHelp, bool fImportZKeys
                 // Successfully imported zaddr.  Now import the metadata.
                 pwalletMain->mapZKeyMetadata[addr].nCreateTime = nTime;
                 continue;
-            }
-            catch (const std::runtime_error &e) {
-                LogPrint("zrpc","Importing detected an error: %s\n", e.what());
+            } else {
+                LogPrint("zrpc", "Importing detected an error: invalid spending key. Trying as a transparent key...\n");
                 // Not a valid spending key, so carry on and see if it's a Zcash style address.
             }
         }
@@ -536,7 +535,7 @@ UniValue dumpwallet_impl(const UniValue& params, bool fHelp, bool fDumpZKeys)
             libzcash::SpendingKey key;
             if (pwalletMain->GetSpendingKey(addr, key)) {
                 std::string strTime = EncodeDumpTime(pwalletMain->mapZKeyMetadata[addr].nCreateTime);
-                file << strprintf("%s %s # zaddr=%s\n", CZCSpendingKey(key).ToString(), strTime, EncodePaymentAddress(addr));
+                file << strprintf("%s %s # zaddr=%s\n", EncodeSpendingKey(key), strTime, EncodePaymentAddress(addr));
             }
         }
         file << "\n";
@@ -614,8 +613,11 @@ UniValue z_importkey(const UniValue& params, bool fHelp)
     }
 
     string strSecret = params[0].get_str();
-    CZCSpendingKey spendingkey(strSecret);
-    auto key = spendingkey.Get();
+    auto spendingkey = DecodeSpendingKey(strSecret);
+    if (!spendingkey) {
+        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid spending key");
+    }
+    auto key = *spendingkey;
     auto addr = key.address();
 
     {
@@ -770,8 +772,7 @@ UniValue z_exportkey(const UniValue& params, bool fHelp)
     if (!pwalletMain->GetSpendingKey(addr, k))
         throw JSONRPCError(RPC_WALLET_ERROR, "Wallet does not hold private zkey for this zaddr");
 
-    CZCSpendingKey spendingkey(k);
-    return spendingkey.ToString();
+    return EncodeSpendingKey(k);
 }
 
 UniValue z_exportviewingkey(const UniValue& params, bool fHelp)

src/wallet/rpcwallet.cpp

@@ -2792,8 +2792,11 @@ UniValue zc_raw_receive(const UniValue& params, bool fHelp)
 
     LOCK(cs_main);
 
-    CZCSpendingKey spendingkey(params[0].get_str());
-    SpendingKey k = spendingkey.Get();
+    auto spendingkey = DecodeSpendingKey(params[0].get_str());
+    if (!spendingkey) {
+        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid spending key");
+    }
+    SpendingKey k = *spendingkey;
 
     uint256 epk;
     unsigned char nonce;
@@ -2903,8 +2906,11 @@ UniValue zc_raw_joinsplit(const UniValue& params, bool fHelp)
     std::vector<uint256> commitments;
 
     for (const string& name_ : inputs.getKeys()) {
-        CZCSpendingKey spendingkey(inputs[name_].get_str());
-        SpendingKey k = spendingkey.Get();
+        auto spendingkey = DecodeSpendingKey(inputs[name_].get_str());
+        if (!spendingkey) {
+            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid spending key");
+        }
+        SpendingKey k = *spendingkey;
 
         keys.push_back(k);
 
@@ -3061,12 +3067,11 @@ UniValue zc_raw_keygen(const UniValue& params, bool fHelp)
     auto addr = k.address();
     auto viewing_key = k.viewing_key();
 
-    CZCSpendingKey spendingkey(k);
     CZCViewingKey viewingkey(viewing_key);
 
     UniValue result(UniValue::VOBJ);
     result.push_back(Pair("zcaddress", EncodePaymentAddress(addr)));
-    result.push_back(Pair("zcsecretkey", spendingkey.ToString()));
+    result.push_back(Pair("zcsecretkey", EncodeSpendingKey(k)));
     result.push_back(Pair("zcviewingkey", viewingkey.ToString()));
     return result;
 }