Add QSsl::Dtls1_0OrLater enumerator

... to make DTLS protocols work  more like TLS protocol versions.
Also, handle (as 'unsupported' for now) those new constants in
a switch statement, when creating SSL_CTX (fixing build errors).

Change-Id: Ia444184ca191d8665e37046b0b9120e43ec5893a
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

src/network/ssl/qssl.cpp

@@ -126,6 +126,7 @@ Q_LOGGING_CATEGORY(lcSsl, "qt.network.ssl");
     \value TlsV1_2 TLSv1.2. When using the WinRT backend this option will also enable TLSv1.0 and TLSv1.1.
     \value TlsV1_2OrLater TLSv1.2 and later versions. This option is not available when using the WinRT backend due to platform limitations.
     \value DtlsV1_0 DTLSv1.0
+    \value DtlsV1_0OrLater DTLSv1.0 and later versions.
     \value DtlsV1_2 DTLSv1.2
     \value DtlsV1_2OrLater DTLSv1.2 and later versions.
     \value UnknownProtocol The cipher's protocol cannot be determined.

src/network/ssl/qssl.h

@@ -92,6 +92,7 @@ namespace QSsl {
         TlsV1_2OrLater,
 
         DtlsV1_0,
+        DtlsV1_0OrLater,
         DtlsV1_2,
         DtlsV1_2OrLater,
 

src/network/ssl/qsslcontext_openssl11.cpp

@@ -139,6 +139,13 @@ init_context:
         minVersion = TLS1_2_VERSION;
         maxVersion = TLS_MAX_VERSION;
         break;
+    case QSsl::DtlsV1_0:
+    case QSsl::DtlsV1_0OrLater:
+    case QSsl::DtlsV1_2:
+    case QSsl::DtlsV1_2OrLater:
+        sslContext->errorStr = QSslSocket::tr("unsupported protocol");
+        sslContext->errorCode = QSslError::UnspecifiedError;
+        return;
     case QSsl::SslV2:
         // This protocol is not supported by OpenSSL 1.1 and we handle
         // it as an error (see the code above).

src/network/ssl/qsslcontext_opensslpre11.cpp

@@ -73,6 +73,13 @@ void QSslContext::initSslContext(QSslContext *sslContext, QSslSocket::SslMode mo
     bool unsupportedProtocol = false;
 init_context:
     switch (sslContext->sslConfiguration.protocol()) {
+    case QSsl::DtlsV1_0:
+    case QSsl::DtlsV1_0OrLater:
+    case QSsl::DtlsV1_2:
+    case QSsl::DtlsV1_2OrLater:
+        sslContext->ctx = 0;
+        unsupportedProtocol = true;
+        break;
     case QSsl::SslV2:
 #ifndef OPENSSL_NO_SSL2
         sslContext->ctx = q_SSL_CTX_new(client ? q_SSLv2_client_method() : q_SSLv2_server_method());