


				CAPA SECURITY


Please follow the instructions as they are given in the README.txt (UPGRADE.txt)
file.  There are security reasons why CAPA is installed the way that it is.  

1.)  Protecting your problem code.
	The README.txt file directs you to create a demolibrary folder 
	which contains symbolic links to the CAPA problem Graphics and 
	Links.  Later, you are directed to make an alias for /demolibrary 
	for the web server using Public/demolibrary.  The reason for this 
	is that the webserver is only allowed to see the Graphics and Links.  
	If you point your browser to http://your.machine/demolibrary/ you 
	can access the Graphics and Links without going through any CAPA 
	security.  If the webserver is aliased to the real demolibrary 
	instead of the Public/demolibrary, anyone (including your students) 
	can access the problem code.  This is highly undesirable and can
	potentially render your CAPA problems useless.  For example, someone
	with your problem code could build their own set with their own
	CAPA software and generate answers for himself/herself and countless
	others.   
	
	Protecting your problems has become particularly important now 
	that CAPA has become free software.  If you add any other libraries 
	to your system, they also MUST have a Public version of the library 
	for the webserver can use.  The CAPA problems (including the 
	demolibrary) are copyrighted by the author, institution, etc. and 
	can NOT be freely distributed.  
	
	To check if your CAPA libraries are properly installed, point your 
	browser to http://your.machine/CAPAlibrary/.  You should only be able 
	to see the Graphics and Links directories.  If your webserver is not 
	set  up for indexing (i.e. you cannot see the directories in your web 
	browser), you can try accessing a problem code file from the web by 
	pointing your browser to 
	http://your.machine/CAPAlibrary/problem-type/problemCode.txt  
	If you can  access such a file, then you need to make a Public version 
	of your library and alias this version in your webserver's srm.conf 
	file.  

2.)  Protecting Web Access
	If you follow the steps above to protect your libraries, then the 
	rest of your CAPA code (set.qz files, etc.) are protected by the 
	capasbin program which has built in security.

3.)  Protecting Telnet Access
	If you use the telnet interface, security is controlled by the 
	capalogin shell.  You should always test out your classes as soon 
	as you install them to make certain that your class "user" (nsc131s0 
	for example) uses the capalogin shell.  This is very important 
	because the "user" (nsc131s0) is set up to log in without a password. 

 