I am writing an application that when is running should modify SystemConfiguration to set system wide proxy.
I know it is possible to do that using "Authorization Services" framework provided by Apple, however I see that it keeps asking for a user password to allow changes.
On the other hand I have 3rd party application (not the one I am writing) that does the same, but does not require user password. The application is not even written in Objective-C, but written in FreePascal (FPC) instead. Unfortunately I have no source code for this application to see how it does this trick.
I know I should be able to achieve the same (system config changes without sudo password) by either having Privileged Helper Tool supplied with the application (and perhaps install it on first run) or by going even nastier and loading a kext.
However I see that this application does neither of above. It only performs system calls and no password asked! I am completely puzzled how did they achieve that and would like to find a way to do the same.
So the question is - how to achieve complete "no password asked" for changing System Configuration on Mac OS X with an application?
PS: Application I have at hand runs as user, not root. And there is no modifications to sudoers neither.
This is silly, but after 2 days straight of searching for a solution I found that there is no special code nor any tricks required.
This is easily done via setting setuid bit to binary that requires escalated privilege and calling setuid(0) in the code before doing operations that require privilege (not sure if second part is necessary).
Relevant links:
PS: This works basically on any Unix-like system (BSD, Linux Solaris etc) with one details - this does not work on scripts (the ones that require hash-bang #! in order to execute interpreter) with exception of Solaris, where it seems to work just fine.