# Rails and Least Privilege Practices

**URL:** <https://www.ruby-forum.com/t/rails-and-least-privilege-practices/117464>\
**Category:** Rails\
**Created:** [October 17, 2007, 7:35am UTC](https://www.ruby-forum.com/t/rails-and-least-privilege-practices/117464 "2007-10-17T07:35:21Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![S-gw](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/ed655f/32.png) [@S-gw](https://www.ruby-forum.com/u/S-gw)\
**Post date:** [October 17, 2007, 7:35am UTC](https://www.ruby-forum.com/t/rails-and-least-privilege-practices/117464/1 "2007-10-17T07:35:21Z")

</div>

Wondering about the practice of running code under the philosophy of  
least privilege inside Rails – or perhaps its a Ruby question. (New to  
both).

I’m used to a language called Lasso which has a security layer between  
the source code and the interpreter (or between the interpreter and the  
runtime engine or wherever). This layer allows me to create containers  
in which code executes with very specific access rights to resources  
like files, and databases (including filtering access to tables and  
specific fields), and even controls access to features of the language  
itself which allows me to deny access to network classes, or reflection  
commands, etc on a per-container basis.

While this can be used to jail individual code contributors to specific  
capabilities and assetts, I also find it useful for implementing Least  
Privilege.

If I have a routine that needs to read config files, I can create a  
“user” named configLoader which allows access to a specific path, and  
has read-only permissions for that path. I then wrap the code in  
container identified as that user. Now, if that code were ever hijacked  
in some never-before-known attack vector, it is useless with respect to  
file system access except for reading that path.

For databases, I can move what I used to define in Lasso Admin to the  
database’s own access management system by defining multiple users into  
those allowed to read only, access only specific tables, etc.

However, for file access, and even certain language feature  
restrictions, I don’t see how that can be done in Ruby or in Rails.

Let’s stick with files. How in Rails would I create a piece of file  
reading code in a method with explicit restrictions to have access to  
path X only and only for reading purposes. IOW, even if I wrote file  
reading commands within the boundaries of this code to get another path  
or to write to a file, it would fail to work.

Does what I am asking make sense?

– gw