Separate URL components before percent-decoding

Allow special characters in query string parameters.
Closes #9116.

src/base/bittorrent/tracker.cpp

@@ -140,8 +140,11 @@ void Tracker::respondToAnnounceRequest()
         const int sepPos = param.indexOf('=');
         if (sepPos <= 0) continue; // ignores params without name
 
-        const QString paramName {QString::fromUtf8(param.constData(), sepPos)};
-        const QByteArray paramValue {param.mid(sepPos + 1)};
+        const QByteArray nameComponent = midView(param, 0, sepPos);
+        const QByteArray valueComponent = midView(param, (sepPos + 1));
+
+        const QString paramName = QString::fromUtf8(QByteArray::fromPercentEncoding(nameComponent));
+        const QByteArray paramValue = QByteArray::fromPercentEncoding(valueComponent);
         queryParams[paramName] = paramValue;
     }
 

src/base/http/requestparser.cpp

@@ -180,11 +180,14 @@ bool RequestParser::parseRequestLine(const QString &line)
     m_request.method = match.captured(1);
 
     // Request Target
-    const QByteArray decodedUrl {QByteArray::fromPercentEncoding(match.captured(2).toLatin1())};
-    const int sepPos = decodedUrl.indexOf('?');
-    m_request.path = QString::fromUtf8(decodedUrl.constData(), (sepPos == -1 ? decodedUrl.size() : sepPos));
+    // URL components should be separated before percent-decoding
+    // [rfc3986] 2.4 When to Encode or Decode
+    const QByteArray url {match.captured(2).toLatin1()};
+    const int sepPos = url.indexOf('?');
+    const QByteArray pathComponent = ((sepPos == -1) ? url : Utils::ByteArray::midView(url, 0, sepPos));
+    m_request.path = QString::fromUtf8(QByteArray::fromPercentEncoding(pathComponent));
     if (sepPos >= 0)
-        m_request.query = decodedUrl.mid(sepPos + 1);
+        m_request.query = url.mid(sepPos + 1);
 
     // HTTP-version
     m_request.version = match.captured(3);

src/webui/webapplication.cpp

@@ -423,10 +423,11 @@ Http::Response WebApplication::processRequest(const Http::Request &request, cons
             const int sepPos = param.indexOf('=');
             if (sepPos <= 0) continue; // ignores params without name
 
-            const QString paramName {QString::fromUtf8(param.constData(), sepPos)};
-            const int valuePos = sepPos + 1;
-            const QString paramValue {
-                QString::fromUtf8(param.constData() + valuePos, param.size() - valuePos)};
+            const QByteArray nameComponent = midView(param, 0, sepPos);
+            const QByteArray valueComponent = midView(param, (sepPos + 1));
+
+            const QString paramName = QString::fromUtf8(QByteArray::fromPercentEncoding(nameComponent));
+            const QString paramValue = QString::fromUtf8(QByteArray::fromPercentEncoding(valueComponent));
             m_params[paramName] = paramValue;
         }
     }