China won't be seen to be directly involved in all this - they have too much to lose internationally in terms of status. All they need to do is continue to provide infrstructure support to North Korea and Iran. Thats where both countries obtain their military technology from (and so does Syria indirectly)
All three countries are effectively Chinese proxies and will kick off a combined war, while Russia will support Syria - as it will distract Turkey and Nato from interference in the Caucasus