For the most part camping is easy along the trail. The Canal Corporation (A division of the NYS Thruway Authority) owns and runs much of the trail. Camping is alowed anywhere next to the trail in those sections, plus there are great campsites that are free in plenty of locations. You can ask any of the lock keepers for permission to camp at any of the lock. I have never been turned down, but be sure to ask instead of assume.... The section from East Syracuse to Rome is owned by New York State Parks and this section is much less camping friendly. There is a paid camping location a few miles east of Syracuse, at Green Lakes State Park, but it is up a huge hill. There are a few places where you can stealth camp nearer to Canastota, but expect noisy train traffic.
Let me know if there is anything else you want to know
Wells Horton
Sherburne, NY