migration: Add helpers to detect TLS capability

Add migrate_channel_requires_tls() to detect whether the specific channel
requires TLS, leveraging the recently introduced migrate_use_tls().  No
functional change intended.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20220707185513.27421-1-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/migration/tls.c b/migration/tls.c
index 32c384a8b6..73e8c9d3c2 100644
--- a/migration/tls.c
+++ b/migration/tls.c
@@ -166,3 +166,12 @@ void migration_tls_channel_connect(MigrationState *s,
                               NULL,
                               NULL);
 }
+
+bool migrate_channel_requires_tls_upgrade(QIOChannel *ioc)
+{
+    if (!migrate_use_tls()) {
+        return false;
+    }
+
+    return !object_dynamic_cast(OBJECT(ioc), TYPE_QIO_CHANNEL_TLS);
+}