skruq wrote:I just wanna know what the T option (Ensures this process can never execute any trojaned code) exactly does. Does it means that there is a hash function calculate on the binary and it is verified each time we execute the binary to be sure that its not a trojaned binary?
no, this is not runtime verification but rather a check of the ACLs before they're loaded into the kernel. the T subject flag ensures that there're no executable objects of the given subject that are writable by other subjects/objects. that is, you can guarantee that the given subject cannot execute code that could have been modified by another.