AppArmor: Add ability to load extended policy

Add the base support for the new policy extensions. This does not bring
any additional functionality, or change current semantics.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Kees Cook <kees@ubuntu.com>

4 files changed, 50 insertions, 1 deletions

diff --git a/security/apparmor/include/apparmor.h b/security/apparmor/include/apparmor.h
index 248c408ddc1b..40aedd9f73ea 100644
--- a/security/apparmor/include/apparmor.h
+++ b/security/apparmor/include/apparmor.h
@@ -19,6 +19,19 @@
 
 #include "match.h"
 
+/*
+ * Class of mediation types in the AppArmor policy db
+ */
+#define AA_CLASS_ENTRY          0
+#define AA_CLASS_UNKNOWN        1
+#define AA_CLASS_FILE           2
+#define AA_CLASS_CAP            3
+#define AA_CLASS_NET            4
+#define AA_CLASS_RLIMITS        5
+#define AA_CLASS_DOMAIN         6
+
+#define AA_CLASS_LAST           AA_CLASS_DOMAIN
+
 /* Control parameters settable through module/boot flags */
 extern enum audit_mode aa_g_audit;
 extern bool aa_g_audit_header;
diff --git a/security/apparmor/include/policy.h b/security/apparmor/include/policy.h
index aeda5cf56904..9e18e9609e24 100644
--- a/security/apparmor/include/policy.h
+++ b/security/apparmor/include/policy.h
@@ -129,6 +129,17 @@ struct aa_namespace {
         struct list_head sub_ns;
 };
 
+/* struct aa_policydb - match engine for a policy
+ * dfa: dfa pattern match
+ * start: set of start states for the different classes of data
+ */
+struct aa_policydb {
+        /* Generic policy DFA specific rule types will be subsections of it */
+        struct aa_dfa *dfa;
+        unsigned int start[AA_CLASS_LAST + 1];
+
+};
+
 /* struct aa_profile - basic confinement data
  * @base - base components of the profile (name, refcount, lists, lock ...)
  * @parent: parent of profile
@@ -143,6 +154,7 @@ struct aa_namespace {
  * @flags: flags controlling profile behavior
  * @path_flags: flags controlling path generation behavior
  * @size: the memory consumed by this profiles rules
+ * @policy: general match rules governing policy
  * @file: The set of rules governing basic file access and domain transitions
  * @caps: capabilities for the profile
  * @rlimits: rlimits for the profile
@@ -179,6 +191,7 @@ struct aa_profile {
         u32 path_flags;
         int size;
 
+        struct aa_policydb policy;
         struct aa_file_rules file;
         struct aa_caps caps;
         struct aa_rlimit rlimits;
diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c
index 4f0eadee78b8..73288d0b541f 100644
--- a/security/apparmor/policy.c
+++ b/security/apparmor/policy.c
@@ -749,6 +749,7 @@ static void free_profile(struct aa_profile *profile)
 
         aa_free_sid(profile->sid);
         aa_put_dfa(profile->xmatch);
+        aa_put_dfa(profile->policy.dfa);
 
         aa_put_profile(profile->replacedby);
 
diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c
index c50634b724b5..25fd51edc8da 100644
--- a/security/apparmor/policy_unpack.c
+++ b/security/apparmor/policy_unpack.c
@@ -469,7 +469,7 @@ static struct aa_profile *unpack_profile(struct aa_ext *e)
 {
         struct aa_profile *profile = NULL;
         const char *name = NULL;
-        int error = -EPROTO;
+        int i, error = -EPROTO;
         kernel_cap_t tmpcap;
         u32 tmp;
 
@@ -562,6 +562,28 @@ static struct aa_profile *unpack_profile(struct aa_ext *e)
         if (!unpack_rlimits(e, profile))
                 goto fail;
 
+        if (unpack_nameX(e, AA_STRUCT, "policydb")) {
+                /* generic policy dfa - optional and may be NULL */
+                profile->policy.dfa = unpack_dfa(e);
+                if (IS_ERR(profile->policy.dfa)) {
+                        error = PTR_ERR(profile->policy.dfa);
+                        profile->policy.dfa = NULL;
+                        goto fail;
+                }
+                if (!unpack_u32(e, &profile->policy.start[0], "start"))
+                        /* default start state */
+                        profile->policy.start[0] = DFA_START;
+                /* setup class index */
+                for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
+                        profile->policy.start[i] =
+                                aa_dfa_next(profile->policy.dfa,
+                                            profile->policy.start[0],
+                                            i);
+                }
+                if (!unpack_nameX(e, AA_STRUCTEND, NULL))
+                        goto fail;
+        }
+
         /* get file rules */
         profile->file.dfa = unpack_dfa(e);
         if (IS_ERR(profile->file.dfa)) {