An Unknown Indian

Thoughts of a FOSS enthusiast

Posts Tagged ‘file permissions’

FOSS and data privacy

Posted by Balachandran on December 23, 2008

Hello folks, A few days back, there was an OT thread in the ilugc, which eventually ran into the topic of data privacy and FOSS. A few people on the list were commenting that data privacy was of supereme importance in FOSS.(The original post).

       I had raised my views over there and wish to highlight them.

File access permissions:

In GNU/Linux, or any other UNIX, the default file access permissions are 755. This means that, the owner can read, write and execute the files. The users in the same group as the owner can read and execute only, and the other users in the system can also read and execute only. (The file access is actually the decimal notation of the bitmask for the r-w-x, where 1 means allowed. So 1-1-1 means read, write and execute and 111 in binary is 7 in decimal).

So this 755 permission by default essentially means that, anybody who has a login in that system can read and execute your files. So the concept of supreme data privacy is lost. Infact, with default settings,any user can read any file in a GNU/Linux system.

There are ofcourse ways to modify the defaul permissions and make it such that the owner can read-write-execute and others can’t do anything, by setting the permissions to 700 using the chmod command. To make this as the default property, the users can also make their umask to be 077. by default umask is set to 022(umask XOR 777 gives the file access permissions).

            There were references to RMS opposing could computing etc. citing that data privacy is lost. In my view,  the probable disadvantage of cloud computing is that data ownership might be lost. But from my understanding, there will be no changes to the privacy.


Posted in FOSS, GNU/Linux | Tagged: , , | 4 Comments »