What's the law on escort and massage permit?

The laws you are talking about are typically city ordinances or state laws.  As such, there's a huge variation from location to location.

Also, there are many parts of the "law on escort and massage permit", and you're not going to get someone to write up a 10,000 word explanation of all the details for free.  You need to ask about a specific part of the law.  A question more like "If I have a massage permit, am I safe from a LE bust?"  (answer: no).