1. 07 Oct, 2009 1 commit
  2. 26 Aug, 2008 1 commit
    • Serge E. Hallyn's avatar
      selinux: add support for installing a dummy policy (v2) · 93c06cbb
      Serge E. Hallyn authored
      In August 2006 I posted a patch generating a minimal SELinux policy.  This
      week, David P. Quigley posted an updated version of that as a patch against
      the kernel.  It also had nice logic for auto-installing the policy.
      
      Following is David's original patch intro (preserved especially
      bc it has stats on the generated policies):
      
      se interested in the changes there were only two significant
      changes. The first is that the iteration through the list of classes
      used NULL as a sentinel value. The problem with this is that the
      class_to_string array actually has NULL entries in its table as place
      holders for the user space object classes.
      
      The second change was that it would seem at some point the initial sids
      table was NULL terminated. This is no longer the case so that iteration
      has to be done on array length instead of looking for NULL.
      
      Some statistics on the policy that it generates:
      
      The policy consists of 523 lines which contain no blank lines. Of those
      523 lines 453 of them are class, permission, and initial sid
      definitions. These lines are usually little to no concern to the policy
      developer since they will not be adding object classes or permissions.
      Of the remaining 70 lines there is one type, one role, and one user
      statement. The remaining lines are broken into three portions. The first
      group are TE allow rules which make up 29 of the remaining lines, the
      second is assignment of labels to the initial sids which consist of 27
      lines, and file system labeling statements which are the remaining 11.
      
      In addition to the policy.conf generated there is a single file_contexts
      file containing two lines which labels the entire system with base_t.
      
      This policy generates a policy.23 binary that is 7920 bytes.
      
      (then a few versions later...):
      
      The new policy is 587 lines (stripped of blank lines) with 476 of those
      lines being the boilerplate that I mentioned last time. The remaining
      111 lines have the 3 lines for type, user, and role, 70 lines for the
      allow rules (one for each object class including user space object
      classes), 27 lines to assign types to the initial sids, and 11 lines for
      file system labeling. The policy binary is 9194 bytes.
      
      Changelog:
      
      	Aug 26: Added Documentation/SELinux.txt
      	Aug 26: Incorporated a set of comments by Stephen Smalley:
      		1. auto-setup SELINUXTYPE=dummy
      		2. don't auto-install if selinux is enabled with
      			non-dummy policy
      		3. don't re-compute policy version
      		4. /sbin/setfiles not /usr/sbin/setfiles
      	Aug 22: As per JMorris comments, made sure make distclean
      		cleans up the mdp directory.
      		Removed a check for file_contexts which is now
      		created in the same file as the check, making it
      		superfluous.
      Signed-off-by: default avatarSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: default avatarDavid Quigley <dpquigl@tycho.nsa.gov>
      Signed-off-by: default avatarJames Morris <jmorris@namei.org>
      93c06cbb