apparmor: split apparmor policy namespaces code into its own file

Policy namespaces will be diverging from profile management and
expanding so put it in its own file.

Signed-off-by: John Johansen <john.johansen@canonical.com>

1 files changed, 14 insertions, 284 deletions

diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c
index a331149a4587..2a861824319e 100644
--- a/security/apparmor/policy.c
+++ b/security/apparmor/policy.c
@@ -85,13 +85,11 @@
 #include "include/match.h"
 #include "include/path.h"
 #include "include/policy.h"
+#include "include/policy_ns.h"
 #include "include/policy_unpack.h"
 #include "include/resource.h"
 
 
-/* root profile namespace */
-struct aa_namespace *root_ns;
-
 const char *const aa_profile_mode_names[] = {
 	"enforce",
 	"complain",
@@ -100,202 +98,16 @@ const char *const aa_profile_mode_names[] = {
 };
 
 
-/*
- * Routines for AppArmor namespaces
- */
-
-static const char *hidden_ns_name = "---";
-/**
- * aa_ns_visible - test if @view is visible from @curr
- * @curr: namespace to treat as the parent (NOT NULL)
- * @view:  namespace to test if visible from @curr (NOT NULL)
- *
- * Returns: true if @view is visible from @curr else false
- */
-bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view)
-{
-	if (curr == view)
-		return true;
-
-	for ( ; view; view = view->parent) {
-		if (view->parent == curr)
-			return true;
-	}
-	return false;
-}
-
-/**
- * aa_na_name - Find the ns name to display for @view from @curr
- * @curr - current namespace (NOT NULL)
- * @view - namespace attempting to view (NOT NULL)
- *
- * Returns: name of @view visible from @curr
- */
-const char *aa_ns_name(struct aa_namespace *curr, struct aa_namespace *view)
-{
-	/* if view == curr then the namespace name isn't displayed */
-	if (curr == view)
-		return "";
-
-	if (aa_ns_visible(curr, view)) {
-		/* at this point if a ns is visible it is in a view ns
-		 * thus the curr ns.hname is a prefix of its name.
-		 * Only output the virtualized portion of the name
-		 * Add + 2 to skip over // separating curr hname prefix
-		 * from the visible tail of the views hname
-		 */
-		return view->base.hname + strlen(curr->base.hname) + 2;
-	} else
-		return hidden_ns_name;
-}
-
-/**
- * alloc_namespace - allocate, initialize and return a new namespace
- * @prefix: parent namespace name (MAYBE NULL)
- * @name: a preallocated name  (NOT NULL)
- *
- * Returns: refcounted namespace or NULL on failure.
- */
-static struct aa_namespace *alloc_namespace(const char *prefix,
-					    const char *name)
-{
-	struct aa_namespace *ns;
-
-	ns = kzalloc(sizeof(*ns), GFP_KERNEL);
-	AA_DEBUG("%s(%p)\n", __func__, ns);
-	if (!ns)
-		return NULL;
-	if (!aa_policy_init(&ns->base, prefix, name))
-		goto fail_ns;
-
-	INIT_LIST_HEAD(&ns->sub_ns);
-	mutex_init(&ns->lock);
-
-	/* released by free_namespace */
-	ns->unconfined = aa_alloc_profile("unconfined");
-	if (!ns->unconfined)
-		goto fail_unconfined;
-
-	ns->unconfined->flags = PFLAG_IX_ON_NAME_ERROR |
-		PFLAG_IMMUTABLE | PFLAG_NS_COUNT;
-	ns->unconfined->mode = APPARMOR_UNCONFINED;
-
-	/* ns and ns->unconfined share ns->unconfined refcount */
-	ns->unconfined->ns = ns;
-
-	atomic_set(&ns->uniq_null, 0);
-
-	return ns;
-
-fail_unconfined:
-	kzfree(ns->base.hname);
-fail_ns:
-	kzfree(ns);
-	return NULL;
-}
-
-/**
- * free_namespace - free a profile namespace
- * @ns: the namespace to free  (MAYBE NULL)
- *
- * Requires: All references to the namespace must have been put, if the
- *           namespace was referenced by a profile confining a task,
- */
-static void free_namespace(struct aa_namespace *ns)
-{
-	if (!ns)
-		return;
-
-	aa_policy_destroy(&ns->base);
-	aa_put_namespace(ns->parent);
-
-	ns->unconfined->ns = NULL;
-	aa_free_profile(ns->unconfined);
-	kzfree(ns);
-}
-
-/**
- * __aa_find_namespace - find a namespace on a list by @name
- * @head: list to search for namespace on  (NOT NULL)
- * @name: name of namespace to look for  (NOT NULL)
- *
- * Returns: unrefcounted namespace
- *
- * Requires: rcu_read_lock be held
- */
-static struct aa_namespace *__aa_find_namespace(struct list_head *head,
-						const char *name)
-{
-	return (struct aa_namespace *)__policy_find(head, name);
-}
-
-/**
- * aa_find_namespace  -  look up a profile namespace on the namespace list
- * @root: namespace to search in  (NOT NULL)
- * @name: name of namespace to find  (NOT NULL)
- *
- * Returns: a refcounted namespace on the list, or NULL if no namespace
- *          called @name exists.
- *
- * refcount released by caller
- */
-struct aa_namespace *aa_find_namespace(struct aa_namespace *root,
-				       const char *name)
-{
-	struct aa_namespace *ns = NULL;
-
-	rcu_read_lock();
-	ns = aa_get_namespace(__aa_find_namespace(&root->sub_ns, name));
-	rcu_read_unlock();
-
-	return ns;
-}
-
-/**
- * aa_prepare_namespace - find an existing or create a new namespace of @name
- * @name: the namespace to find or add  (MAYBE NULL)
- *
- * Returns: refcounted namespace or NULL if failed to create one
- */
-static struct aa_namespace *aa_prepare_namespace(const char *name)
+/* requires profile list write lock held */
+void __aa_update_replacedby(struct aa_profile *orig, struct aa_profile *new)
 {
-	struct aa_namespace *ns, *root;
-
-	root = aa_current_profile()->ns;
-
-	mutex_lock(&root->lock);
-
-	/* if name isn't specified the profile is loaded to the current ns */
-	if (!name) {
-		/* released by caller */
-		ns = aa_get_namespace(root);
-		goto out;
-	}
+	struct aa_profile *tmp;
 
-	/* try and find the specified ns and if it doesn't exist create it */
-	/* released by caller */
-	ns = aa_get_namespace(__aa_find_namespace(&root->sub_ns, name));
-	if (!ns) {
-		ns = alloc_namespace(root->base.hname, name);
-		if (!ns)
-			goto out;
-		if (__aa_fs_namespace_mkdir(ns, ns_subns_dir(root), name)) {
-			AA_ERROR("Failed to create interface for ns %s\n",
-				 ns->base.name);
-			free_namespace(ns);
-			ns = NULL;
-			goto out;
-		}
-		ns->parent = aa_get_namespace(root);
-		list_add_rcu(&ns->base.list, &root->sub_ns);
-		/* add list ref */
-		aa_get_namespace(ns);
-	}
-out:
-	mutex_unlock(&root->lock);
-
-	/* return ref */
-	return ns;
+	tmp = rcu_dereference_protected(orig->replacedby->profile,
+					mutex_is_locked(&orig->ns->lock));
+	rcu_assign_pointer(orig->replacedby->profile, aa_get_profile(new));
+	orig->flags |= PFLAG_INVALID;
+	aa_put_profile(tmp);
 }
 
 /**
@@ -333,8 +145,6 @@ static void __list_remove_profile(struct aa_profile *profile)
 	aa_put_profile(profile);
 }
 
-static void __profile_list_release(struct list_head *head);
-
 /**
  * __remove_profile - remove old profile, and children
  * @profile: profile to be replaced  (NOT NULL)
@@ -344,7 +154,7 @@ static void __profile_list_release(struct list_head *head);
 static void __remove_profile(struct aa_profile *profile)
 {
 	/* release any children lists first */
-	__profile_list_release(&profile->base.profiles);
+	__aa_profile_list_release(&profile->base.profiles);
 	/* released by free_profile */
 	__aa_update_replacedby(profile, profile->ns->unconfined);
 	__aa_fs_profile_rmdir(profile);
@@ -352,98 +162,18 @@ static void __remove_profile(struct aa_profile *profile)
 }
 
 /**
- * __profile_list_release - remove all profiles on the list and put refs
+ * __aa_profile_list_release - remove all profiles on the list and put refs
  * @head: list of profiles  (NOT NULL)
  *
  * Requires: namespace lock be held
  */
-static void __profile_list_release(struct list_head *head)
+void __aa_profile_list_release(struct list_head *head)
 {
 	struct aa_profile *profile, *tmp;
 	list_for_each_entry_safe(profile, tmp, head, base.list)
 		__remove_profile(profile);
 }
 
-static void __ns_list_release(struct list_head *head);
-
-/**
- * destroy_namespace - remove everything contained by @ns
- * @ns: namespace to have it contents removed  (NOT NULL)
- */
-static void destroy_namespace(struct aa_namespace *ns)
-{
-	if (!ns)
-		return;
-
-	mutex_lock(&ns->lock);
-	/* release all profiles in this namespace */
-	__profile_list_release(&ns->base.profiles);
-
-	/* release all sub namespaces */
-	__ns_list_release(&ns->sub_ns);
-
-	if (ns->parent)
-		__aa_update_replacedby(ns->unconfined, ns->parent->unconfined);
-	__aa_fs_namespace_rmdir(ns);
-	mutex_unlock(&ns->lock);
-}
-
-/**
- * __remove_namespace - remove a namespace and all its children
- * @ns: namespace to be removed  (NOT NULL)
- *
- * Requires: ns->parent->lock be held and ns removed from parent.
- */
-static void __remove_namespace(struct aa_namespace *ns)
-{
-	/* remove ns from namespace list */
-	list_del_rcu(&ns->base.list);
-	destroy_namespace(ns);
-	aa_put_namespace(ns);
-}
-
-/**
- * __ns_list_release - remove all profile namespaces on the list put refs
- * @head: list of profile namespaces  (NOT NULL)
- *
- * Requires: namespace lock be held
- */
-static void __ns_list_release(struct list_head *head)
-{
-	struct aa_namespace *ns, *tmp;
-	list_for_each_entry_safe(ns, tmp, head, base.list)
-		__remove_namespace(ns);
-
-}
-
-/**
- * aa_alloc_root_ns - allocate the root profile namespace
- *
- * Returns: %0 on success else error
- *
- */
-int __init aa_alloc_root_ns(void)
-{
-	/* released by aa_free_root_ns - used as list ref*/
-	root_ns = alloc_namespace(NULL, "root");
-	if (!root_ns)
-		return -ENOMEM;
-
-	return 0;
-}
-
- /**
-  * aa_free_root_ns - free the root profile namespace
-  */
-void __init aa_free_root_ns(void)
- {
-	 struct aa_namespace *ns = root_ns;
-	 root_ns = NULL;
-
-	 destroy_namespace(ns);
-	 aa_put_namespace(ns);
-}
-
 
 static void free_replacedby(struct aa_replacedby *r)
 {
@@ -507,7 +237,7 @@ static void aa_free_profile_rcu(struct rcu_head *head)
 {
 	struct aa_profile *p = container_of(head, struct aa_profile, rcu);
 	if (p->flags & PFLAG_NS_COUNT)
-		free_namespace(p->ns);
+		aa_free_namespace(p->ns);
 	else
 		aa_free_profile(p);
 }
@@ -1181,7 +911,7 @@ ssize_t aa_remove_profiles(char *fqname, size_t size)
 	if (!name) {
 		/* remove namespace - can only happen if fqname[0] == ':' */
 		mutex_lock(&ns->parent->lock);
-		__remove_namespace(ns);
+		__aa_remove_namespace(ns);
 		mutex_unlock(&ns->parent->lock);
 	} else {
 		/* remove profile */