--- /dev/null
+/*
+ * AppArmor security module
+ *
+ * This file contains AppArmor policy manipulation functions
+ *
+ * Copyright (C) 1998-2008 Novell/SUSE
+ * Copyright 2009-2010 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2 of the
+ * License.
+ *
+ *
+ * AppArmor policy is based around profiles, which contain the rules a
+ * task is confined by. Every task in the system has a profile attached
+ * to it determined either by matching "unconfined" tasks against the
+ * visible set of profiles or by following a profiles attachment rules.
+ *
+ * Each profile exists in a profile namespace which is a container of
+ * visible profiles. Each namespace contains a special "unconfined" profile,
+ * which doesn't enforce any confinement on a task beyond DAC.
+ *
+ * Namespace and profile names can be written together in either
+ * of two syntaxes.
+ * :namespace:profile - used by kernel interfaces for easy detection
+ * namespace://profile - used by policy
+ *
+ * Profile names can not start with : or @ or ^ and may not contain \0
+ *
+ * Reserved profile names
+ * unconfined - special automatically generated unconfined profile
+ * inherit - special name to indicate profile inheritance
+ * null-XXXX-YYYY - special automatically generated learning profiles
+ *
+ * Namespace names may not start with / or @ and may not contain \0 or :
+ * Reserved namespace names
+ * user-XXXX - user defined profiles
+ *
+ * a // in a profile or namespace name indicates a hierarchical name with the
+ * name before the // being the parent and the name after the child.
+ *
+ * Profile and namespace hierarchies serve two different but similar purposes.
+ * The namespace contains the set of visible profiles that are considered
+ * for attachment. The hierarchy of namespaces allows for virtualizing
+ * the namespace so that for example a chroot can have its own set of profiles
+ * which may define some local user namespaces.
+ * The profile hierarchy severs two distinct purposes,
+ * - it allows for sub profiles or hats, which allows an application to run
+ * subprograms under its own profile with different restriction than it
+ * self, and not have it use the system profile.
+ * eg. if a mail program starts an editor, the policy might make the
+ * restrictions tighter on the editor tighter than the mail program,
+ * and definitely different than general editor restrictions
+ * - it allows for binary hierarchy of profiles, so that execution history
+ * is preserved. This feature isn't exploited by AppArmor reference policy
+ * but is allowed. NOTE: this is currently suboptimal because profile
+ * aliasing is not currently implemented so that a profile for each
+ * level must be defined.
+ * eg. /bin/bash///bin/ls as a name would indicate /bin/ls was started
+ * from /bin/bash
+ *
+ * A profile or namespace name that can contain one or more // separators
+ * is referred to as an hname (hierarchical).
+ * eg. /bin/bash//bin/ls
+ *
+ * An fqname is a name that may contain both namespace and profile hnames.
+ * eg. :ns:/bin/bash//bin/ls
+ *
+ * NOTES:
+ * - locking of profile lists is currently fairly coarse. All profile
+ * lists within a namespace use the namespace lock.
+ * FIXME: move profile lists to using rcu_lists
+ */
+
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+#include "include/apparmor.h"
+#include "include/capability.h"
+#include "include/context.h"
+#include "include/file.h"
+#include "include/ipc.h"
+#include "include/match.h"
+#include "include/path.h"
+#include "include/policy.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",
+ "kill",
+ "unconfined",
+};
+
+/**
+ * hname_tail - find the last component of an hname
+ * @name: hname to find the base profile name component of (NOT NULL)
+ *
+ * Returns: the tail (base profile name) name component of an hname
+ */
+static const char *hname_tail(const char *hname)
+{
+ char *split;
+ hname = strim((char *)hname);
+ for (split = strstr(hname, "//"); split; split = strstr(hname, "//"))
+ hname = split + 2;
+
+ return hname;
+}
+
+/**
+ * policy_init - initialize a policy structure
+ * @policy: policy to initialize (NOT NULL)
+ * @prefix: prefix name if any is required. (MAYBE NULL)
+ * @name: name of the policy, init will make a copy of it (NOT NULL)
+ *
+ * Note: this fn creates a copy of strings passed in
+ *
+ * Returns: true if policy init successful
+ */
+static bool policy_init(struct aa_policy *policy, const char *prefix,
+ const char *name)
+{
+ /* freed by policy_free */
+ if (prefix) {
+ policy->hname = kmalloc(strlen(prefix) + strlen(name) + 3,
+ GFP_KERNEL);
+ if (policy->hname)
+ sprintf(policy->hname, "%s//%s", prefix, name);
+ } else
+ policy->hname = kstrdup(name, GFP_KERNEL);
+ if (!policy->hname)
+ return 0;
+ /* base.name is a substring of fqname */
+ policy->name = (char *)hname_tail(policy->hname);
+ INIT_LIST_HEAD(&policy->list);
+ INIT_LIST_HEAD(&policy->profiles);
+
+ return 1;
+}
+
+/**
+ * policy_destroy - free the elements referenced by @policy
+ * @policy: policy that is to have its elements freed (NOT NULL)
+ */
+static void policy_destroy(struct aa_policy *policy)
+{
+ /* still contains profiles -- invalid */
+ if (on_list_rcu(&policy->profiles)) {
+ AA_ERROR("%s: internal error, "
+ "policy '%s' still contains profiles\n",
+ __func__, policy->name);
+ BUG();
+ }
+ if (on_list_rcu(&policy->list)) {
+ AA_ERROR("%s: internal error, policy '%s' still on list\n",
+ __func__, policy->name);
+ BUG();
+ }
+
+ /* don't free name as its a subset of hname */
+ kzfree(policy->hname);
+}
+
+/**
+ * __policy_find - find a policy by @name on a policy list
+ * @head: list to search (NOT NULL)
+ * @name: name to search for (NOT NULL)
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy that match @name or NULL if not found
+ */
+static struct aa_policy *__policy_find(struct list_head *head, const char *name)
+{
+ struct aa_policy *policy;
+
+ list_for_each_entry_rcu(policy, head, list) {
+ if (!strcmp(policy->name, name))
+ return policy;
+ }
+ return NULL;
+}
+
+/**
+ * __policy_strn_find - find a policy that's name matches @len chars of @str
+ * @head: list to search (NOT NULL)
+ * @str: string to search for (NOT NULL)
+ * @len: length of match required
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy that match @str or NULL if not found
+ *
+ * if @len == strlen(@strlen) then this is equiv to __policy_find
+ * other wise it allows searching for policy by a partial match of name
+ */
+static struct aa_policy *__policy_strn_find(struct list_head *head,
+ const char *str, int len)
+{
+ struct aa_policy *policy;
+
+ list_for_each_entry_rcu(policy, head, list) {
+ if (aa_strneq(policy->name, str, len))
+ return policy;
+ }
+
+ return NULL;
+}
+
+/*
+ * 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 (!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;
+
+ 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)
+{
+ 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;
+ }
+
+ /* 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;
+}
+
+/**
+ * __list_add_profile - add a profile to a list
+ * @list: list to add it to (NOT NULL)
+ * @profile: the profile to add (NOT NULL)
+ *
+ * refcount @profile, should be put by __list_remove_profile
+ *
+ * Requires: namespace lock be held, or list not be shared
+ */
+static void __list_add_profile(struct list_head *list,
+ struct aa_profile *profile)
+{
+ list_add_rcu(&profile->base.list, list);
+ /* get list reference */
+ aa_get_profile(profile);
+}
+
+/**
+ * __list_remove_profile - remove a profile from the list it is on
+ * @profile: the profile to remove (NOT NULL)
+ *
+ * remove a profile from the list, warning generally removal should
+ * be done with __replace_profile as most profile removals are
+ * replacements to the unconfined profile.
+ *
+ * put @profile list refcount
+ *
+ * Requires: namespace lock be held, or list not have been live
+ */
+static void __list_remove_profile(struct aa_profile *profile)
+{
+ list_del_rcu(&profile->base.list);
+ 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)
+ *
+ * Requires: namespace list lock be held, or list not be shared
+ */
+static void __remove_profile(struct aa_profile *profile)
+{
+ /* release any children lists first */
+ __profile_list_release(&profile->base.profiles);
+ /* released by free_profile */
+ __aa_update_replacedby(profile, profile->ns->unconfined);
+ __aa_fs_profile_rmdir(profile);
+ __list_remove_profile(profile);
+}
+
+/**
+ * __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)
+{
+ 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)
+{
+ if (r) {
+ /* r->profile will not be updated any more as r is dead */
+ aa_put_profile(rcu_dereference_protected(r->profile, true));
+ kzfree(r);
+ }
+}
+
+
+void aa_free_replacedby_kref(struct kref *kref)
+{
+ struct aa_replacedby *r = container_of(kref, struct aa_replacedby,
+ count);
+ free_replacedby(r);
+}
+
+/**
+ * aa_free_profile - free a profile
+ * @profile: the profile to free (MAYBE NULL)
+ *
+ * Free a profile, its hats and null_profile. All references to the profile,
+ * its hats and null_profile must have been put.
+ *
+ * If the profile was referenced from a task context, free_profile() will
+ * be called from an rcu callback routine, so we must not sleep here.
+ */
+void aa_free_profile(struct aa_profile *profile)
+{
+ AA_DEBUG("%s(%p)\n", __func__, profile);
+
+ if (!profile)
+ return;
+
+ /* free children profiles */
+ policy_destroy(&profile->base);
+ aa_put_profile(rcu_access_pointer(profile->parent));
+
+ aa_put_namespace(profile->ns);
+ kzfree(profile->rename);
+
+ aa_free_file_rules(&profile->file);
+ aa_free_cap_rules(&profile->caps);
+ aa_free_rlimit_rules(&profile->rlimits);
+
+ kzfree(profile->dirname);
+ aa_put_dfa(profile->xmatch);
+ aa_put_dfa(profile->policy.dfa);
+ aa_put_replacedby(profile->replacedby);
+
+ kzfree(profile->hash);
+ kzfree(profile);
+}
+
+/**
+ * aa_free_profile_rcu - free aa_profile by rcu (called by aa_free_profile_kref)
+ * @head: rcu_head callback for freeing of a profile (NOT NULL)
+ */
+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);
+ else
+ aa_free_profile(p);
+}
+
+/**
+ * aa_free_profile_kref - free aa_profile by kref (called by aa_put_profile)
+ * @kr: kref callback for freeing of a profile (NOT NULL)
+ */
+void aa_free_profile_kref(struct kref *kref)
+{
+ struct aa_profile *p = container_of(kref, struct aa_profile, count);
+ call_rcu(&p->rcu, aa_free_profile_rcu);
+}
+
+/**
+ * aa_alloc_profile - allocate, initialize and return a new profile
+ * @hname: name of the profile (NOT NULL)
+ *
+ * Returns: refcount profile or NULL on failure
+ */
+struct aa_profile *aa_alloc_profile(const char *hname)
+{
+ struct aa_profile *profile;
+
+ /* freed by free_profile - usually through aa_put_profile */
+ profile = kzalloc(sizeof(*profile), GFP_KERNEL);
+ if (!profile)
+ return NULL;
+
+ profile->replacedby = kzalloc(sizeof(struct aa_replacedby), GFP_KERNEL);
+ if (!profile->replacedby)
+ goto fail;
+ kref_init(&profile->replacedby->count);
+
+ if (!policy_init(&profile->base, NULL, hname))
+ goto fail;
+ kref_init(&profile->count);
+
+ /* refcount released by caller */
+ return profile;
+
+fail:
+ kzfree(profile->replacedby);
+ kzfree(profile);
+
+ return NULL;
+}
+
+/**
+ * aa_new_null_profile - create a new null-X learning profile
+ * @parent: profile that caused this profile to be created (NOT NULL)
+ * @hat: true if the null- learning profile is a hat
+ *
+ * Create a null- complain mode profile used in learning mode. The name of
+ * the profile is unique and follows the format of parent//null-<uniq>.
+ *
+ * null profiles are added to the profile list but the list does not
+ * hold a count on them so that they are automatically released when
+ * not in use.
+ *
+ * Returns: new refcounted profile else NULL on failure
+ */
+struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat)
+{
+ struct aa_profile *profile = NULL;
+ char *name;
+ int uniq = atomic_inc_return(&parent->ns->uniq_null);
+
+ /* freed below */
+ name = kmalloc(strlen(parent->base.hname) + 2 + 7 + 8, GFP_KERNEL);
+ if (!name)
+ goto fail;
+ sprintf(name, "%s//null-%x", parent->base.hname, uniq);
+
+ profile = aa_alloc_profile(name);
+ kfree(name);
+ if (!profile)
+ goto fail;
+
+ profile->mode = APPARMOR_COMPLAIN;
+ profile->flags = PFLAG_NULL;
+ if (hat)
+ profile->flags |= PFLAG_HAT;
+
+ /* released on free_profile */
+ rcu_assign_pointer(profile->parent, aa_get_profile(parent));
+ profile->ns = aa_get_namespace(parent->ns);
+
+ mutex_lock(&profile->ns->lock);
+ __list_add_profile(&parent->base.profiles, profile);
+ mutex_unlock(&profile->ns->lock);
+
+ /* refcount released by caller */
+ return profile;
+
+fail:
+ return NULL;
+}
+
+/* TODO: profile accounting - setup in remove */
+
+/**
+ * __find_child - find a profile on @head list with a name matching @name
+ * @head: list to search (NOT NULL)
+ * @name: name of profile (NOT NULL)
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted profile ptr, or NULL if not found
+ */
+static struct aa_profile *__find_child(struct list_head *head, const char *name)
+{
+ return (struct aa_profile *)__policy_find(head, name);
+}
+
+/**
+ * __strn_find_child - find a profile on @head list using substring of @name
+ * @head: list to search (NOT NULL)
+ * @name: name of profile (NOT NULL)
+ * @len: length of @name substring to match
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted profile ptr, or NULL if not found
+ */
+static struct aa_profile *__strn_find_child(struct list_head *head,
+ const char *name, int len)
+{
+ return (struct aa_profile *)__policy_strn_find(head, name, len);
+}
+
+/**
+ * aa_find_child - find a profile by @name in @parent
+ * @parent: profile to search (NOT NULL)
+ * @name: profile name to search for (NOT NULL)
+ *
+ * Returns: a refcounted profile or NULL if not found
+ */
+struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name)
+{
+ struct aa_profile *profile;
+
+ rcu_read_lock();
+ profile = aa_get_profile(__find_child(&parent->base.profiles, name));
+ rcu_read_unlock();
+
+ /* refcount released by caller */
+ return profile;
+}
+
+/**
+ * __lookup_parent - lookup the parent of a profile of name @hname
+ * @ns: namespace to lookup profile in (NOT NULL)
+ * @hname: hierarchical profile name to find parent of (NOT NULL)
+ *
+ * Lookups up the parent of a fully qualified profile name, the profile
+ * that matches hname does not need to exist, in general this
+ * is used to load a new profile.
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted policy or NULL if not found
+ */
+static struct aa_policy *__lookup_parent(struct aa_namespace *ns,
+ const char *hname)
+{
+ struct aa_policy *policy;
+ struct aa_profile *profile = NULL;
+ char *split;
+
+ policy = &ns->base;
+
+ for (split = strstr(hname, "//"); split;) {
+ profile = __strn_find_child(&policy->profiles, hname,
+ split - hname);
+ if (!profile)
+ return NULL;
+ policy = &profile->base;
+ hname = split + 2;
+ split = strstr(hname, "//");
+ }
+ if (!profile)
+ return &ns->base;
+ return &profile->base;
+}
+
+/**
+ * __lookup_profile - lookup the profile matching @hname
+ * @base: base list to start looking up profile name from (NOT NULL)
+ * @hname: hierarchical profile name (NOT NULL)
+ *
+ * Requires: rcu_read_lock be held
+ *
+ * Returns: unrefcounted profile pointer or NULL if not found
+ *
+ * Do a relative name lookup, recursing through profile tree.
+ */
+static struct aa_profile *__lookup_profile(struct aa_policy *base,
+ const char *hname)
+{
+ struct aa_profile *profile = NULL;
+ char *split;
+
+ for (split = strstr(hname, "//"); split;) {
+ profile = __strn_find_child(&base->profiles, hname,
+ split - hname);
+ if (!profile)
+ return NULL;
+
+ base = &profile->base;
+ hname = split + 2;
+ split = strstr(hname, "//");
+ }
+
+ profile = __find_child(&base->profiles, hname);
+
+ return profile;
+}
+
+/**
+ * aa_lookup_profile - find a profile by its full or partial name
+ * @ns: the namespace to start from (NOT NULL)
+ * @hname: name to do lookup on. Does not contain namespace prefix (NOT NULL)
+ *
+ * Returns: refcounted profile or NULL if not found
+ */
+struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *hname)
+{
+ struct aa_profile *profile;
+
+ rcu_read_lock();
+ do {
+ profile = __lookup_profile(&ns->base, hname);
+ } while (profile && !aa_get_profile_not0(profile));
+ rcu_read_unlock();
+
+ /* the unconfined profile is not in the regular profile list */
+ if (!profile && strcmp(hname, "unconfined") == 0)
+ profile = aa_get_newest_profile(ns->unconfined);
+
+ /* refcount released by caller */
+ return profile;
+}
+
+/**
+ * replacement_allowed - test to see if replacement is allowed
+ * @profile: profile to test if it can be replaced (MAYBE NULL)
+ * @noreplace: true if replacement shouldn't be allowed but addition is okay
+ * @info: Returns - info about why replacement failed (NOT NULL)
+ *
+ * Returns: %0 if replacement allowed else error code
+ */
+static int replacement_allowed(struct aa_profile *profile, int noreplace,
+ const char **info)
+{
+ if (profile) {
+ if (profile->flags & PFLAG_IMMUTABLE) {
+ *info = "cannot replace immutible profile";
+ return -EPERM;
+ } else if (noreplace) {
+ *info = "profile already exists";
+ return -EEXIST;
+ }
+ }
+ return 0;
+}
+
+/**
+ * aa_audit_policy - Do auditing of policy changes
+ * @op: policy operation being performed
+ * @gfp: memory allocation flags
+ * @name: name of profile being manipulated (NOT NULL)
+ * @info: any extra information to be audited (MAYBE NULL)
+ * @error: error code
+ *
+ * Returns: the error to be returned after audit is done
+ */
+static int audit_policy(int op, gfp_t gfp, const char *name, const char *info,
+ int error)
+{
+ struct common_audit_data sa;
+ struct apparmor_audit_data aad = {0,};
+ sa.type = LSM_AUDIT_DATA_NONE;
+ sa.aad = &aad;
+ aad.op = op;
+ aad.name = name;
+ aad.info = info;
+ aad.error = error;
+
+ return aa_audit(AUDIT_APPARMOR_STATUS, __aa_current_profile(), gfp,
+ &sa, NULL);
+}
+
+/**
+ * aa_may_manage_policy - can the current task manage policy
+ * @op: the policy manipulation operation being done
+ *
+ * Returns: true if the task is allowed to manipulate policy
+ */
+bool aa_may_manage_policy(int op)
+{
+ /* check if loading policy is locked out */
+ if (aa_g_lock_policy) {
+ audit_policy(op, GFP_KERNEL, NULL, "policy_locked", -EACCES);
+ return 0;
+ }
+
+ if (!capable(CAP_MAC_ADMIN)) {
+ audit_policy(op, GFP_KERNEL, NULL, "not policy admin", -EACCES);
+ return 0;
+ }
+
+ return 1;
+}
+
+static struct aa_profile *__list_lookup_parent(struct list_head *lh,
+ struct aa_profile *profile)
+{
+ const char *base = hname_tail(profile->base.hname);
+ long len = base - profile->base.hname;
+ struct aa_load_ent *ent;
+
+ /* parent won't have trailing // so remove from len */
+ if (len <= 2)
+ return NULL;
+ len -= 2;
+
+ list_for_each_entry(ent, lh, list) {
+ if (ent->new == profile)
+ continue;
+ if (strncmp(ent->new->base.hname, profile->base.hname, len) ==
+ 0 && ent->new->base.hname[len] == 0)
+ return ent->new;
+ }
+
+ return NULL;
+}
+
+/**
+ * __replace_profile - replace @old with @new on a list
+ * @old: profile to be replaced (NOT NULL)
+ * @new: profile to replace @old with (NOT NULL)
+ * @share_replacedby: transfer @old->replacedby to @new
+ *
+ * Will duplicate and refcount elements that @new inherits from @old
+ * and will inherit @old children.
+ *
+ * refcount @new for list, put @old list refcount
+ *
+ * Requires: namespace list lock be held, or list not be shared
+ */
+static void __replace_profile(struct aa_profile *old, struct aa_profile *new,
+ bool share_replacedby)
+{
+ struct aa_profile *child, *tmp;
+
+ if (!list_empty(&old->base.profiles)) {
+ LIST_HEAD(lh);
+ list_splice_init_rcu(&old->base.profiles, &lh, synchronize_rcu);
+
+ list_for_each_entry_safe(child, tmp, &lh, base.list) {
+ struct aa_profile *p;
+
+ list_del_init(&child->base.list);
+ p = __find_child(&new->base.profiles, child->base.name);
+ if (p) {
+ /* @p replaces @child */
+ __replace_profile(child, p, share_replacedby);
+ continue;
+ }
+
+ /* inherit @child and its children */
+ /* TODO: update hname of inherited children */
+ /* list refcount transferred to @new */
+ p = aa_deref_parent(child);
+ rcu_assign_pointer(child->parent, aa_get_profile(new));
+ list_add_rcu(&child->base.list, &new->base.profiles);
+ aa_put_profile(p);
+ }
+ }
+
+ if (!rcu_access_pointer(new->parent)) {
+ struct aa_profile *parent = aa_deref_parent(old);
+ rcu_assign_pointer(new->parent, aa_get_profile(parent));
+ }
+ __aa_update_replacedby(old, new);
+ if (share_replacedby) {
+ aa_put_replacedby(new->replacedby);
+ new->replacedby = aa_get_replacedby(old->replacedby);
+ } else if (!rcu_access_pointer(new->replacedby->profile))
+ /* aafs interface uses replacedby */
+ rcu_assign_pointer(new->replacedby->profile,
+ aa_get_profile(new));
+ __aa_fs_profile_migrate_dents(old, new);
+
+ if (list_empty(&new->base.list)) {
+ /* new is not on a list already */
+ list_replace_rcu(&old->base.list, &new->base.list);
+ aa_get_profile(new);
+ aa_put_profile(old);
+ } else
+ __list_remove_profile(old);
+}
+
+/**
+ * __lookup_replace - lookup replacement information for a profile
+ * @ns - namespace the lookup occurs in
+ * @hname - name of profile to lookup
+ * @noreplace - true if not replacing an existing profile
+ * @p - Returns: profile to be replaced
+ * @info - Returns: info string on why lookup failed
+ *
+ * Returns: profile to replace (no ref) on success else ptr error
+ */
+static int __lookup_replace(struct aa_namespace *ns, const char *hname,
+ bool noreplace, struct aa_profile **p,
+ const char **info)
+{
+ *p = aa_get_profile(__lookup_profile(&ns->base, hname));
+ if (*p) {
+ int error = replacement_allowed(*p, noreplace, info);
+ if (error) {
+ *info = "profile can not be replaced";
+ return error;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * aa_replace_profiles - replace profile(s) on the profile list
+ * @udata: serialized data stream (NOT NULL)
+ * @size: size of the serialized data stream
+ * @noreplace: true if only doing addition, no replacement allowed
+ *
+ * unpack and replace a profile on the profile list and uses of that profile
+ * by any aa_task_cxt. If the profile does not exist on the profile list
+ * it is added.
+ *
+ * Returns: size of data consumed else error code on failure.
+ */
+ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace)
+{
+ const char *ns_name, *name = NULL, *info = NULL;
+ struct aa_namespace *ns = NULL;
+ struct aa_load_ent *ent, *tmp;
+ int op = OP_PROF_REPL;
+ ssize_t error;
+ LIST_HEAD(lh);
+
+ /* released below */
+ error = aa_unpack(udata, size, &lh, &ns_name);
+ if (error)
+ goto out;
+
+ /* released below */
+ ns = aa_prepare_namespace(ns_name);
+ if (!ns) {
+ info = "failed to prepare namespace";
+ error = -ENOMEM;
+ name = ns_name;
+ goto fail;
+ }
+
+ mutex_lock(&ns->lock);
+ /* setup parent and ns info */
+ list_for_each_entry(ent, &lh, list) {
+ struct aa_policy *policy;
+
+ name = ent->new->base.hname;
+ error = __lookup_replace(ns, ent->new->base.hname, noreplace,
+ &ent->old, &info);
+ if (error)
+ goto fail_lock;
+
+ if (ent->new->rename) {
+ error = __lookup_replace(ns, ent->new->rename,
+ noreplace, &ent->rename,
+ &info);
+ if (error)
+ goto fail_lock;
+ }
+
+ /* released when @new is freed */
+ ent->new->ns = aa_get_namespace(ns);
+
+ if (ent->old || ent->rename)
+ continue;
+
+ /* no ref on policy only use inside lock */
+ policy = __lookup_parent(ns, ent->new->base.hname);
+ if (!policy) {
+ struct aa_profile *p;
+ p = __list_lookup_parent(&lh, ent->new);
+ if (!p) {
+ error = -ENOENT;
+ info = "parent does not exist";
+ name = ent->new->base.hname;
+ goto fail_lock;
+ }
+ rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
+ } else if (policy != &ns->base) {
+ /* released on profile replacement or free_profile */
+ struct aa_profile *p = (struct aa_profile *) policy;
+ rcu_assign_pointer(ent->new->parent, aa_get_profile(p));
+ }
+ }
+
+ /* create new fs entries for introspection if needed */
+ list_for_each_entry(ent, &lh, list) {
+ if (ent->old) {
+ /* inherit old interface files */
+
+ /* if (ent->rename)
+ TODO: support rename */
+ /* } else if (ent->rename) {
+ TODO: support rename */
+ } else {
+ struct dentry *parent;
+ if (rcu_access_pointer(ent->new->parent)) {
+ struct aa_profile *p;
+ p = aa_deref_parent(ent->new);
+ parent = prof_child_dir(p);
+ } else
+ parent = ns_subprofs_dir(ent->new->ns);
+ error = __aa_fs_profile_mkdir(ent->new, parent);
+ }
+
+ if (error) {
+ info = "failed to create ";
+ goto fail_lock;
+ }
+ }
+
+ /* Done with checks that may fail - do actual replacement */
+ list_for_each_entry_safe(ent, tmp, &lh, list) {
+ list_del_init(&ent->list);
+ op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
+
+ audit_policy(op, GFP_ATOMIC, ent->new->base.name, NULL, error);
+
+ if (ent->old) {
+ __replace_profile(ent->old, ent->new, 1);
+ if (ent->rename) {
+ /* aafs interface uses replacedby */
+ struct aa_replacedby *r = ent->new->replacedby;
+ rcu_assign_pointer(r->profile,
+ aa_get_profile(ent->new));
+ __replace_profile(ent->rename, ent->new, 0);
+ }
+ } else if (ent->rename) {
+ /* aafs interface uses replacedby */
+ rcu_assign_pointer(ent->new->replacedby->profile,
+ aa_get_profile(ent->new));
+ __replace_profile(ent->rename, ent->new, 0);
+ } else if (ent->new->parent) {
+ struct aa_profile *parent, *newest;
+ parent = aa_deref_parent(ent->new);
+ newest = aa_get_newest_profile(parent);
+
+ /* parent replaced in this atomic set? */
+ if (newest != parent) {
+ aa_get_profile(newest);
+ aa_put_profile(parent);
+ rcu_assign_pointer(ent->new->parent, newest);
+ } else
+ aa_put_profile(newest);
+ /* aafs interface uses replacedby */
+ rcu_assign_pointer(ent->new->replacedby->profile,
+ aa_get_profile(ent->new));
+ __list_add_profile(&parent->base.profiles, ent->new);
+ } else {
+ /* aafs interface uses replacedby */
+ rcu_assign_pointer(ent->new->replacedby->profile,
+ aa_get_profile(ent->new));
+ __list_add_profile(&ns->base.profiles, ent->new);
+ }
+ aa_load_ent_free(ent);
+ }
+ mutex_unlock(&ns->lock);
+
+out:
+ aa_put_namespace(ns);
+
+ if (error)
+ return error;
+ return size;
+
+fail_lock:
+ mutex_unlock(&ns->lock);
+fail:
+ error = audit_policy(op, GFP_KERNEL, name, info, error);
+
+ list_for_each_entry_safe(ent, tmp, &lh, list) {
+ list_del_init(&ent->list);
+ aa_load_ent_free(ent);
+ }
+
+ goto out;
+}
+
+/**
+ * aa_remove_profiles - remove profile(s) from the system
+ * @fqname: name of the profile or namespace to remove (NOT NULL)
+ * @size: size of the name
+ *
+ * Remove a profile or sub namespace from the current namespace, so that
+ * they can not be found anymore and mark them as replaced by unconfined
+ *
+ * NOTE: removing confinement does not restore rlimits to preconfinemnet values
+ *
+ * Returns: size of data consume else error code if fails
+ */
+ssize_t aa_remove_profiles(char *fqname, size_t size)
+{
+ struct aa_namespace *root, *ns = NULL;
+ struct aa_profile *profile = NULL;
+ const char *name = fqname, *info = NULL;
+ ssize_t error = 0;
+
+ if (*fqname == 0) {
+ info = "no profile specified";
+ error = -ENOENT;
+ goto fail;
+ }
+
+ root = aa_current_profile()->ns;
+
+ if (fqname[0] == ':') {
+ char *ns_name;
+ name = aa_split_fqname(fqname, &ns_name);
+ /* released below */
+ ns = aa_find_namespace(root, ns_name);
+ if (!ns) {
+ info = "namespace does not exist";
+ error = -ENOENT;
+ goto fail;
+ }
+ } else
+ /* released below */
+ ns = aa_get_namespace(root);
+
+ if (!name) {
+ /* remove namespace - can only happen if fqname[0] == ':' */
+ mutex_lock(&ns->parent->lock);
+ __remove_namespace(ns);
+ mutex_unlock(&ns->parent->lock);
+ } else {
+ /* remove profile */
+ mutex_lock(&ns->lock);
+ profile = aa_get_profile(__lookup_profile(&ns->base, name));
+ if (!profile) {
+ error = -ENOENT;
+ info = "profile does not exist";
+ goto fail_ns_lock;
+ }
+ name = profile->base.hname;
+ __remove_profile(profile);
+ mutex_unlock(&ns->lock);
+ }
+
+ /* don't fail removal if audit fails */
+ (void) audit_policy(OP_PROF_RM, GFP_KERNEL, name, info, error);
+ aa_put_namespace(ns);
+ aa_put_profile(profile);
+ return size;
+
+fail_ns_lock:
+ mutex_unlock(&ns->lock);
+ aa_put_namespace(ns);
+
+fail:
+ (void) audit_policy(OP_PROF_RM, GFP_KERNEL, name, info, error);
+ return error;
+}
Code Review / kvmfornfv.git / blobdiff