refactor: Add sanity checks in LabelFromValue

Author: aureleoules

src/wallet/rpc/addresses.cpp

@@ -43,9 +43,7 @@ RPCHelpMan getnewaddress()
     }
 
     // Parse the label first so we don't generate a key if there's an error
-    std::string label;
-    if (!request.params[0].isNull())
-        label = LabelFromValue(request.params[0]);
+    const std::string label{LabelFromValue(request.params[0])};
 
     OutputType output_type = pwallet->m_default_address_type;
     if (!request.params[1].isNull()) {
@@ -140,7 +138,7 @@ RPCHelpMan setlabel()
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid Bitcoin address");
     }
 
-    std::string label = LabelFromValue(request.params[1]);
+    const std::string label{LabelFromValue(request.params[1])};
 
     if (pwallet->IsMine(dest)) {
         pwallet->SetAddressBook(dest, label, "receive");
@@ -258,9 +256,7 @@ RPCHelpMan addmultisigaddress()
 
     LOCK2(pwallet->cs_wallet, spk_man.cs_KeyStore);
 
-    std::string label;
-    if (!request.params[2].isNull())
-        label = LabelFromValue(request.params[2]);
+    const std::string label{LabelFromValue(request.params[2])};
 
     int required = request.params[0].getInt<int>();
 
@@ -662,7 +658,7 @@ RPCHelpMan getaddressesbylabel()
 
     LOCK(pwallet->cs_wallet);
 
-    std::string label = LabelFromValue(request.params[0]);
+    const std::string label{LabelFromValue(request.params[0])};
 
     // Find all addresses that have the given label
     UniValue ret(UniValue::VOBJ);

src/wallet/rpc/backup.cpp

@@ -140,9 +140,7 @@ RPCHelpMan importprivkey()
         EnsureWalletIsUnlocked(*pwallet);
 
         std::string strSecret = request.params[0].get_str();
-        std::string strLabel;
-        if (!request.params[1].isNull())
-            strLabel = LabelFromValue(request.params[1]);
+        const std::string strLabel{LabelFromValue(request.params[1])};
 
         // Whether to perform rescan after import
         if (!request.params[2].isNull())
@@ -233,9 +231,7 @@ RPCHelpMan importaddress()
 
     EnsureLegacyScriptPubKeyMan(*pwallet, true);
 
-    std::string strLabel;
-    if (!request.params[1].isNull())
-        strLabel = LabelFromValue(request.params[1]);
+    const std::string strLabel{LabelFromValue(request.params[1])};
 
     // Whether to perform rescan after import
     bool fRescan = true;
@@ -426,9 +422,7 @@ RPCHelpMan importpubkey()
 
     EnsureLegacyScriptPubKeyMan(*pwallet, true);
 
-    std::string strLabel;
-    if (!request.params[1].isNull())
-        strLabel = LabelFromValue(request.params[1]);
+    const std::string strLabel{LabelFromValue(request.params[1])};
 
     // Whether to perform rescan after import
     bool fRescan = true;
@@ -1163,7 +1157,7 @@ static UniValue ProcessImport(CWallet& wallet, const UniValue& data, const int64
         if (internal && data.exists("label")) {
             throw JSONRPCError(RPC_INVALID_PARAMETER, "Internal addresses should not have a label");
         }
-        const std::string& label = data.exists("label") ? LabelFromValue(data["label"]) : "";
+        const std::string label{LabelFromValue(data["label"])};
         const bool add_keypool = data.exists("keypool") ? data["keypool"].get_bool() : false;
 
         // Add to keypool only works with privkeys disabled
@@ -1457,7 +1451,7 @@ static UniValue ProcessDescriptorImport(CWallet& wallet, const UniValue& data, c
         const std::string& descriptor = data["desc"].get_str();
         const bool active = data.exists("active") ? data["active"].get_bool() : false;
         const bool internal = data.exists("internal") ? data["internal"].get_bool() : false;
-        const std::string& label = data.exists("label") ? LabelFromValue(data["label"]) : "";
+        const std::string label{LabelFromValue(data["label"])};
 
         // Parse descriptor string
         FlatSigningProvider keys;

src/wallet/rpc/transactions.cpp

@@ -635,10 +635,9 @@ RPCHelpMan listsinceblock()
     bool include_removed = (request.params[3].isNull() || request.params[3].get_bool());
     bool include_change = (!request.params[4].isNull() && request.params[4].get_bool());
 
+    // Only set it if 'label' was provided.
     std::optional<std::string> filter_label;
-    if (!request.params[5].isNull()) {
-        filter_label = LabelFromValue(request.params[5]);
-    }
+    if (!request.params[5].isNull()) filter_label.emplace(LabelFromValue(request.params[5]));
 
     int depth = height ? wallet.GetLastBlockHeight() + 1 - *height : -1;
 

src/wallet/rpc/util.cpp

@@ -132,7 +132,10 @@ const LegacyScriptPubKeyMan& EnsureConstLegacyScriptPubKeyMan(const CWallet& wal
 
 std::string LabelFromValue(const UniValue& value)
 {
-    std::string label = value.get_str();
+    static const std::string empty_string;
+    if (value.isNull()) return empty_string;
+
+    const std::string& label{value.get_str()};
     if (label == "*")
         throw JSONRPCError(RPC_WALLET_INVALID_LABEL_NAME, "Invalid label name");
     return label;