selinux: dynamic class/perm discovery

Modify SELinux to dynamically discover class and permission values
upon policy load, based on the dynamic object class/perm discovery
logic from libselinux.  A mapping is created between kernel-private
class and permission indices used outside the security server and the
policy values used within the security server.

The mappings are only applied upon kernel-internal computations;
similar mappings for the private indices of userspace object managers
is handled on a per-object manager basis by the userspace AVC.  The
interfaces for compute_av and transition_sid are split for kernel
vs. userspace; the userspace functions are distinguished by a _user
suffix.

The kernel-private class indices are no longer tied to the policy
values and thus do not need to skip indices for userspace classes;
thus the kernel class index values are compressed.  The flask.h
definitions were regenerated by deleting the userspace classes from
refpolicy's definitions and then regenerating the headers.  Going
forward, we can just maintain the flask.h, av_permissions.h, and
classmap.h definitions separately from policy as they are no longer
tied to the policy values.  The next patch introduces a utility to
automate generation of flask.h and av_permissions.h from the
classmap.h definitions.

The older kernel class and permission string tables are removed and
replaced by a single security class mapping table that is walked at
policy load to generate the mapping.  The old kernel class validation
logic is completely replaced by the mapping logic.

The handle unknown logic is reworked.  reject_unknown=1 is handled
when the mappings are computed at policy load time, similar to the old
handling by the class validation logic.  allow_unknown=1 is handled
when computing and mapping decisions - if the permission was not able
to be mapped (i.e. undefined, mapped to zero), then it is
automatically added to the allowed vector.  If the class was not able
to be mapped (i.e. undefined, mapped to zero), then all permissions
are allowed for it if allow_unknown=1.

avc_audit leverages the new security class mapping table to lookup the
class and permission names from the kernel-private indices.

The mdp program is updated to use the new table when generating the
class definitions and allow rules for a minimal boot policy for the
kernel.  It should be noted that this policy will not include any
userspace classes, nor will its policy index values for the kernel
classes correspond with the ones in refpolicy (they will instead match
the kernel-private indices).

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 22 insertions, 22 deletions

diff --git a/security/selinux/include/av_permissions.h b/security/selinux/include/av_permissions.h
index 0546d616ccac..fef2582b734d 100644
--- a/security/selinux/include/av_permissions.h
+++ b/security/selinux/include/av_permissions.h
@@ -423,28 +423,6 @@
 #define UNIX_DGRAM_SOCKET__RECV_MSG               0x00080000UL
 #define UNIX_DGRAM_SOCKET__SEND_MSG               0x00100000UL
 #define UNIX_DGRAM_SOCKET__NAME_BIND              0x00200000UL
-#define TUN_SOCKET__IOCTL                         0x00000001UL
-#define TUN_SOCKET__READ                          0x00000002UL
-#define TUN_SOCKET__WRITE                         0x00000004UL
-#define TUN_SOCKET__CREATE                        0x00000008UL
-#define TUN_SOCKET__GETATTR                       0x00000010UL
-#define TUN_SOCKET__SETATTR                       0x00000020UL
-#define TUN_SOCKET__LOCK                          0x00000040UL
-#define TUN_SOCKET__RELABELFROM                   0x00000080UL
-#define TUN_SOCKET__RELABELTO                     0x00000100UL
-#define TUN_SOCKET__APPEND                        0x00000200UL
-#define TUN_SOCKET__BIND                          0x00000400UL
-#define TUN_SOCKET__CONNECT                       0x00000800UL
-#define TUN_SOCKET__LISTEN                        0x00001000UL
-#define TUN_SOCKET__ACCEPT                        0x00002000UL
-#define TUN_SOCKET__GETOPT                        0x00004000UL
-#define TUN_SOCKET__SETOPT                        0x00008000UL
-#define TUN_SOCKET__SHUTDOWN                      0x00010000UL
-#define TUN_SOCKET__RECVFROM                      0x00020000UL
-#define TUN_SOCKET__SENDTO                        0x00040000UL
-#define TUN_SOCKET__RECV_MSG                      0x00080000UL
-#define TUN_SOCKET__SEND_MSG                      0x00100000UL
-#define TUN_SOCKET__NAME_BIND                     0x00200000UL
 #define PROCESS__FORK                             0x00000001UL
 #define PROCESS__TRANSITION                       0x00000002UL
 #define PROCESS__SIGCHLD                          0x00000004UL
@@ -868,3 +846,25 @@
 #define PEER__RECV                                0x00000001UL
 #define KERNEL_SERVICE__USE_AS_OVERRIDE           0x00000001UL
 #define KERNEL_SERVICE__CREATE_FILES_AS           0x00000002UL
+#define TUN_SOCKET__IOCTL                         0x00000001UL
+#define TUN_SOCKET__READ                          0x00000002UL
+#define TUN_SOCKET__WRITE                         0x00000004UL
+#define TUN_SOCKET__CREATE                        0x00000008UL
+#define TUN_SOCKET__GETATTR                       0x00000010UL
+#define TUN_SOCKET__SETATTR                       0x00000020UL
+#define TUN_SOCKET__LOCK                          0x00000040UL
+#define TUN_SOCKET__RELABELFROM                   0x00000080UL
+#define TUN_SOCKET__RELABELTO                     0x00000100UL
+#define TUN_SOCKET__APPEND                        0x00000200UL
+#define TUN_SOCKET__BIND                          0x00000400UL
+#define TUN_SOCKET__CONNECT                       0x00000800UL
+#define TUN_SOCKET__LISTEN                        0x00001000UL
+#define TUN_SOCKET__ACCEPT                        0x00002000UL
+#define TUN_SOCKET__GETOPT                        0x00004000UL
+#define TUN_SOCKET__SETOPT                        0x00008000UL
+#define TUN_SOCKET__SHUTDOWN                      0x00010000UL
+#define TUN_SOCKET__RECVFROM                      0x00020000UL
+#define TUN_SOCKET__SENDTO                        0x00040000UL
+#define TUN_SOCKET__RECV_MSG                      0x00080000UL
+#define TUN_SOCKET__SEND_MSG                      0x00100000UL
+#define TUN_SOCKET__NAME_BIND                     0x00200000UL