SELinux: Add class support to the role_trans structure

If kernel policy version is >= 26, then the binary representation of
the role_trans structure supports specifying the class for the current
subject or the newly created object.

If kernel policy version is < 26, then the class field would be default
to the process class.

Signed-off-by: Harry Ciao <qingtao.cao@windriver.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Eric Paris <eparis@redhat.com>

3 files changed, 18 insertions, 2 deletions

diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
index 348eb00cb668..bfc5218d5840 100644
--- a/security/selinux/include/security.h
+++ b/security/selinux/include/security.h
@@ -30,13 +30,14 @@
 #define POLICYDB_VERSION_PERMISSIVE     23
 #define POLICYDB_VERSION_BOUNDARY       24
 #define POLICYDB_VERSION_FILENAME_TRANS 25
+#define POLICYDB_VERSION_ROLETRANS      26
 
 /* Range of policy versions we understand*/
 #define POLICYDB_VERSION_MIN   POLICYDB_VERSION_BASE
 #ifdef CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX
 #define POLICYDB_VERSION_MAX    CONFIG_SECURITY_SELINUX_POLICYDB_VERSION_MAX_VALUE
 #else
-#define POLICYDB_VERSION_MAX    POLICYDB_VERSION_FILENAME_TRANS
+#define POLICYDB_VERSION_MAX    POLICYDB_VERSION_ROLETRANS
 #endif
 
 /* Mask for just the mount related flags */
diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index e7b850ad57ee..fd62c50d6e7d 100644
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -128,6 +128,11 @@ static struct policydb_compat_info policydb_compat[] = {
                 .sym_num        = SYM_NUM,
                 .ocon_num       = OCON_NUM,
         },
+        {
+                .version        = POLICYDB_VERSION_ROLETRANS,
+                .sym_num        = SYM_NUM,
+                .ocon_num       = OCON_NUM,
+        },
 };
 
 static struct policydb_compat_info *policydb_lookup_compat(int version)
@@ -2302,8 +2307,17 @@ int policydb_read(struct policydb *p, void *fp)
                 tr->role = le32_to_cpu(buf[0]);
                 tr->type = le32_to_cpu(buf[1]);
                 tr->new_role = le32_to_cpu(buf[2]);
+                if (p->policyvers >= POLICYDB_VERSION_ROLETRANS) {
+                        rc = next_entry(buf, fp, sizeof(u32));
+                        if (rc)
+                                goto bad;
+                        tr->tclass = le32_to_cpu(buf[0]);
+                } else
+                        tr->tclass = p->process_class;
+
                 if (!policydb_role_isvalid(p, tr->role) ||
                     !policydb_type_isvalid(p, tr->type) ||
+                    !policydb_class_isvalid(p, tr->tclass) ||
                     !policydb_role_isvalid(p, tr->new_role))
                         goto bad;
                 ltr = tr;
diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h
index 732ea4a68682..801175f79cf9 100644
--- a/security/selinux/ss/policydb.h
+++ b/security/selinux/ss/policydb.h
@@ -72,7 +72,8 @@ struct role_datum {
 
 struct role_trans {
         u32 role;               /* current role */
-        u32 type;               /* program executable type */
+        u32 type;               /* program executable type, or new object type */
+        u32 tclass;             /* process class, or new object class */
         u32 new_role;           /* new role */
         struct role_trans *next;
 };