apparmor: add interface files for profiles and namespaces

Add basic interface files to access namespace and profile information.
The interface files are created when a profile is loaded and removed
when the profile or namespace is removed.

Signed-off-by: John Johansen <john.johansen@canonical.com>
This commit is contained in:
John Johansen 2013-07-10 21:13:43 -07:00
parent 038165070a
commit 0d259f043f
7 changed files with 436 additions and 29 deletions

View file

@ -12,6 +12,7 @@
* License.
*/
#include <linux/ctype.h>
#include <linux/security.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
@ -27,6 +28,45 @@
#include "include/policy.h"
#include "include/resource.h"
/**
* aa_mangle_name - mangle a profile name to std profile layout form
* @name: profile name to mangle (NOT NULL)
* @target: buffer to store mangled name, same length as @name (MAYBE NULL)
*
* Returns: length of mangled name
*/
static int mangle_name(char *name, char *target)
{
char *t = target;
while (*name == '/' || *name == '.')
name++;
if (target) {
for (; *name; name++) {
if (*name == '/')
*(t)++ = '.';
else if (isspace(*name))
*(t)++ = '_';
else if (isalnum(*name) || strchr("._-", *name))
*(t)++ = *name;
}
*t = 0;
} else {
int len = 0;
for (; *name; name++) {
if (isalnum(*name) || isspace(*name) ||
strchr("/._-", *name))
len++;
}
return len;
}
return t - target;
}
/**
* aa_simple_write_to_buffer - common routine for getting policy from user
* @op: operation doing the user buffer copy
@ -182,8 +222,263 @@ const struct file_operations aa_fs_seq_file_ops = {
.release = single_release,
};
/** Base file system setup **/
static int aa_fs_seq_profile_open(struct inode *inode, struct file *file,
int (*show)(struct seq_file *, void *))
{
struct aa_replacedby *r = aa_get_replacedby(inode->i_private);
int error = single_open(file, show, r);
if (error) {
file->private_data = NULL;
aa_put_replacedby(r);
}
return error;
}
static int aa_fs_seq_profile_release(struct inode *inode, struct file *file)
{
struct seq_file *seq = (struct seq_file *) file->private_data;
if (seq)
aa_put_replacedby(seq->private);
return single_release(inode, file);
}
static int aa_fs_seq_profname_show(struct seq_file *seq, void *v)
{
struct aa_replacedby *r = seq->private;
struct aa_profile *profile = aa_get_profile_rcu(&r->profile);
seq_printf(seq, "%s\n", profile->base.name);
aa_put_profile(profile);
return 0;
}
static int aa_fs_seq_profname_open(struct inode *inode, struct file *file)
{
return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profname_show);
}
static const struct file_operations aa_fs_profname_fops = {
.owner = THIS_MODULE,
.open = aa_fs_seq_profname_open,
.read = seq_read,
.llseek = seq_lseek,
.release = aa_fs_seq_profile_release,
};
static int aa_fs_seq_profmode_show(struct seq_file *seq, void *v)
{
struct aa_replacedby *r = seq->private;
struct aa_profile *profile = aa_get_profile_rcu(&r->profile);
seq_printf(seq, "%s\n", aa_profile_mode_names[profile->mode]);
aa_put_profile(profile);
return 0;
}
static int aa_fs_seq_profmode_open(struct inode *inode, struct file *file)
{
return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profmode_show);
}
static const struct file_operations aa_fs_profmode_fops = {
.owner = THIS_MODULE,
.open = aa_fs_seq_profmode_open,
.read = seq_read,
.llseek = seq_lseek,
.release = aa_fs_seq_profile_release,
};
/** fns to setup dynamic per profile/namespace files **/
void __aa_fs_profile_rmdir(struct aa_profile *profile)
{
struct aa_profile *child;
int i;
if (!profile)
return;
list_for_each_entry(child, &profile->base.profiles, base.list)
__aa_fs_profile_rmdir(child);
for (i = AAFS_PROF_SIZEOF - 1; i >= 0; --i) {
struct aa_replacedby *r;
if (!profile->dents[i])
continue;
r = profile->dents[i]->d_inode->i_private;
securityfs_remove(profile->dents[i]);
aa_put_replacedby(r);
profile->dents[i] = NULL;
}
}
void __aa_fs_profile_migrate_dents(struct aa_profile *old,
struct aa_profile *new)
{
int i;
for (i = 0; i < AAFS_PROF_SIZEOF; i++) {
new->dents[i] = old->dents[i];
old->dents[i] = NULL;
}
}
static struct dentry *create_profile_file(struct dentry *dir, const char *name,
struct aa_profile *profile,
const struct file_operations *fops)
{
struct aa_replacedby *r = aa_get_replacedby(profile->replacedby);
struct dentry *dent;
dent = securityfs_create_file(name, S_IFREG | 0444, dir, r, fops);
if (IS_ERR(dent))
aa_put_replacedby(r);
return dent;
}
/* requires lock be held */
int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
{
struct aa_profile *child;
struct dentry *dent = NULL, *dir;
int error;
if (!parent) {
struct aa_profile *p;
p = aa_deref_parent(profile);
dent = prof_dir(p);
/* adding to parent that previously didn't have children */
dent = securityfs_create_dir("profiles", dent);
if (IS_ERR(dent))
goto fail;
prof_child_dir(p) = parent = dent;
}
if (!profile->dirname) {
int len, id_len;
len = mangle_name(profile->base.name, NULL);
id_len = snprintf(NULL, 0, ".%ld", profile->ns->uniq_id);
profile->dirname = kmalloc(len + id_len + 1, GFP_KERNEL);
if (!profile->dirname)
goto fail;
mangle_name(profile->base.name, profile->dirname);
sprintf(profile->dirname + len, ".%ld", profile->ns->uniq_id++);
}
dent = securityfs_create_dir(profile->dirname, parent);
if (IS_ERR(dent))
goto fail;
prof_dir(profile) = dir = dent;
dent = create_profile_file(dir, "name", profile, &aa_fs_profname_fops);
if (IS_ERR(dent))
goto fail;
profile->dents[AAFS_PROF_NAME] = dent;
dent = create_profile_file(dir, "mode", profile, &aa_fs_profmode_fops);
if (IS_ERR(dent))
goto fail;
profile->dents[AAFS_PROF_MODE] = dent;
list_for_each_entry(child, &profile->base.profiles, base.list) {
error = __aa_fs_profile_mkdir(child, prof_child_dir(profile));
if (error)
goto fail2;
}
return 0;
fail:
error = PTR_ERR(dent);
fail2:
__aa_fs_profile_rmdir(profile);
return error;
}
void __aa_fs_namespace_rmdir(struct aa_namespace *ns)
{
struct aa_namespace *sub;
struct aa_profile *child;
int i;
if (!ns)
return;
list_for_each_entry(child, &ns->base.profiles, base.list)
__aa_fs_profile_rmdir(child);
list_for_each_entry(sub, &ns->sub_ns, base.list) {
mutex_lock(&sub->lock);
__aa_fs_namespace_rmdir(sub);
mutex_unlock(&sub->lock);
}
for (i = AAFS_NS_SIZEOF - 1; i >= 0; --i) {
securityfs_remove(ns->dents[i]);
ns->dents[i] = NULL;
}
}
int __aa_fs_namespace_mkdir(struct aa_namespace *ns, struct dentry *parent,
const char *name)
{
struct aa_namespace *sub;
struct aa_profile *child;
struct dentry *dent, *dir;
int error;
if (!name)
name = ns->base.name;
dent = securityfs_create_dir(name, parent);
if (IS_ERR(dent))
goto fail;
ns_dir(ns) = dir = dent;
dent = securityfs_create_dir("profiles", dir);
if (IS_ERR(dent))
goto fail;
ns_subprofs_dir(ns) = dent;
dent = securityfs_create_dir("namespaces", dir);
if (IS_ERR(dent))
goto fail;
ns_subns_dir(ns) = dent;
list_for_each_entry(child, &ns->base.profiles, base.list) {
error = __aa_fs_profile_mkdir(child, ns_subprofs_dir(ns));
if (error)
goto fail2;
}
list_for_each_entry(sub, &ns->sub_ns, base.list) {
mutex_lock(&sub->lock);
error = __aa_fs_namespace_mkdir(sub, ns_subns_dir(ns), NULL);
mutex_unlock(&sub->lock);
if (error)
goto fail2;
}
return 0;
fail:
error = PTR_ERR(dent);
fail2:
__aa_fs_namespace_rmdir(ns);
return error;
}
/** Base file system setup **/
static struct aa_fs_entry aa_fs_entry_file[] = {
AA_FS_FILE_STRING("mask", "create read write exec append mmap_exec " \
"link lock"),
@ -246,6 +541,7 @@ static int __init aafs_create_file(struct aa_fs_entry *fs_file,
return error;
}
static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir);
/**
* aafs_create_dir - recursively create a directory entry in the securityfs
* @fs_dir: aa_fs_entry (and all child entries) to build (NOT NULL)
@ -256,17 +552,16 @@ static int __init aafs_create_file(struct aa_fs_entry *fs_file,
static int __init aafs_create_dir(struct aa_fs_entry *fs_dir,
struct dentry *parent)
{
int error;
struct aa_fs_entry *fs_file;
struct dentry *dir;
int error;
fs_dir->dentry = securityfs_create_dir(fs_dir->name, parent);
if (IS_ERR(fs_dir->dentry)) {
error = PTR_ERR(fs_dir->dentry);
fs_dir->dentry = NULL;
goto failed;
}
dir = securityfs_create_dir(fs_dir->name, parent);
if (IS_ERR(dir))
return PTR_ERR(dir);
fs_dir->dentry = dir;
for (fs_file = fs_dir->v.files; fs_file->name; ++fs_file) {
for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) {
if (fs_file->v_type == AA_FS_TYPE_DIR)
error = aafs_create_dir(fs_file, fs_dir->dentry);
else
@ -278,6 +573,8 @@ static int __init aafs_create_dir(struct aa_fs_entry *fs_dir,
return 0;
failed:
aafs_remove_dir(fs_dir);
return error;
}
@ -302,7 +599,7 @@ static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir)
{
struct aa_fs_entry *fs_file;
for (fs_file = fs_dir->v.files; fs_file->name; ++fs_file) {
for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) {
if (fs_file->v_type == AA_FS_TYPE_DIR)
aafs_remove_dir(fs_file);
else
@ -346,6 +643,11 @@ static int __init aa_create_aafs(void)
if (error)
goto error;
error = __aa_fs_namespace_mkdir(root_ns, aa_fs_entry.dentry,
"policy");
if (error)
goto error;
/* TODO: add support for apparmorfs_null and apparmorfs_mnt */
/* Report that AppArmor fs is enabled */

View file

@ -61,4 +61,42 @@ extern const struct file_operations aa_fs_seq_file_ops;
extern void __init aa_destroy_aafs(void);
struct aa_profile;
struct aa_namespace;
enum aafs_ns_type {
AAFS_NS_DIR,
AAFS_NS_PROFS,
AAFS_NS_NS,
AAFS_NS_COUNT,
AAFS_NS_MAX_COUNT,
AAFS_NS_SIZE,
AAFS_NS_MAX_SIZE,
AAFS_NS_OWNER,
AAFS_NS_SIZEOF,
};
enum aafs_prof_type {
AAFS_PROF_DIR,
AAFS_PROF_PROFS,
AAFS_PROF_NAME,
AAFS_PROF_MODE,
AAFS_PROF_SIZEOF,
};
#define ns_dir(X) ((X)->dents[AAFS_NS_DIR])
#define ns_subns_dir(X) ((X)->dents[AAFS_NS_NS])
#define ns_subprofs_dir(X) ((X)->dents[AAFS_NS_PROFS])
#define prof_dir(X) ((X)->dents[AAFS_PROF_DIR])
#define prof_child_dir(X) ((X)->dents[AAFS_PROF_PROFS])
void __aa_fs_profile_rmdir(struct aa_profile *profile);
void __aa_fs_profile_migrate_dents(struct aa_profile *old,
struct aa_profile *new);
int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent);
void __aa_fs_namespace_rmdir(struct aa_namespace *ns);
int __aa_fs_namespace_mkdir(struct aa_namespace *ns, struct dentry *parent,
const char *name);
#endif /* __AA_APPARMORFS_H */

View file

@ -27,7 +27,6 @@ struct aa_profile;
extern const char *const audit_mode_names[];
#define AUDIT_MAX_INDEX 5
enum audit_mode {
AUDIT_NORMAL, /* follow normal auditing of accesses */
AUDIT_QUIET_DENIED, /* quiet all denied access messages */

View file

@ -29,8 +29,8 @@
#include "file.h"
#include "resource.h"
extern const char *const profile_mode_names[];
#define APPARMOR_NAMES_MAX_INDEX 3
extern const char *const aa_profile_mode_names[];
#define APPARMOR_MODE_NAMES_MAX_INDEX 4
#define PROFILE_MODE(_profile, _mode) \
((aa_g_profile_mode == (_mode)) || \
@ -110,6 +110,8 @@ struct aa_ns_acct {
* @unconfined: special unconfined profile for the namespace
* @sub_ns: list of namespaces under the current namespace.
* @uniq_null: uniq value used for null learning profiles
* @uniq_id: a unique id count for the profiles in the namespace
* @dents: dentries for the namespaces file entries in apparmorfs
*
* An aa_namespace defines the set profiles that are searched to determine
* which profile to attach to a task. Profiles can not be shared between
@ -133,6 +135,9 @@ struct aa_namespace {
struct aa_profile *unconfined;
struct list_head sub_ns;
atomic_t uniq_null;
long uniq_id;
struct dentry *dents[AAFS_NS_SIZEOF];
};
/* struct aa_policydb - match engine for a policy
@ -172,6 +177,9 @@ struct aa_replacedby {
* @caps: capabilities for the profile
* @rlimits: rlimits for the profile
*
* @dents: dentries for the profiles file entries in apparmorfs
* @dirname: name of the profile dir in apparmorfs
*
* The AppArmor profile contains the basic confinement data. Each profile
* has a name, and exists in a namespace. The @name and @exec_match are
* used to determine profile attachment against unconfined tasks. All other
@ -208,6 +216,9 @@ struct aa_profile {
struct aa_file_rules file;
struct aa_caps caps;
struct aa_rlimit rlimits;
char *dirname;
struct dentry *dents[AAFS_PROF_SIZEOF];
};
extern struct aa_namespace *root_ns;
@ -243,6 +254,12 @@ ssize_t aa_remove_profiles(char *name, size_t size);
#define unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
static inline struct aa_profile *aa_deref_parent(struct aa_profile *p)
{
return rcu_dereference_protected(p->parent,
mutex_is_locked(&p->ns->lock));
}
/**
* aa_get_profile - increment refcount on profile @p
* @p: profile (MAYBE NULL)

View file

@ -843,7 +843,7 @@ static int param_get_mode(char *buffer, struct kernel_param *kp)
if (!apparmor_enabled)
return -EINVAL;
return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]);
return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
}
static int param_set_mode(const char *val, struct kernel_param *kp)
@ -858,8 +858,8 @@ static int param_set_mode(const char *val, struct kernel_param *kp)
if (!val)
return -EINVAL;
for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) {
if (strcmp(val, profile_mode_names[i]) == 0) {
for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
if (strcmp(val, aa_profile_mode_names[i]) == 0) {
aa_g_profile_mode = i;
return 0;
}

View file

@ -92,7 +92,7 @@
/* root profile namespace */
struct aa_namespace *root_ns;
const char *const profile_mode_names[] = {
const char *const aa_profile_mode_names[] = {
"enforce",
"complain",
"kill",
@ -394,7 +394,13 @@ static struct aa_namespace *aa_prepare_namespace(const char *name)
ns = alloc_namespace(root->base.hname, name);
if (!ns)
goto out;
/* add parent ref */
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 */
@ -456,6 +462,7 @@ static void __remove_profile(struct aa_profile *profile)
__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);
}
@ -492,6 +499,7 @@ static void destroy_namespace(struct aa_namespace *ns)
if (ns->parent)
__aa_update_replacedby(ns->unconfined, ns->parent->unconfined);
__aa_fs_namespace_rmdir(ns);
mutex_unlock(&ns->lock);
}
@ -596,6 +604,7 @@ void aa_free_profile(struct aa_profile *profile)
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);
@ -986,8 +995,7 @@ static void __replace_profile(struct aa_profile *old, struct aa_profile *new,
/* inherit @child and its children */
/* TODO: update hname of inherited children */
/* list refcount transferred to @new */
p = rcu_dereference_protected(child->parent,
mutex_is_locked(&child->ns->lock));
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);
@ -995,14 +1003,18 @@ static void __replace_profile(struct aa_profile *old, struct aa_profile *new,
}
if (!rcu_access_pointer(new->parent)) {
struct aa_profile *parent = rcu_dereference(old->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 */
@ -1118,7 +1130,33 @@ ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace)
}
}
/* do actual replacement */
/* 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;
@ -1127,14 +1165,21 @@ ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace)
if (ent->old) {
__replace_profile(ent->old, ent->new, 1);
if (ent->rename)
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 = rcu_dereference_protected(ent->new->parent,
mutex_is_locked(&ns->lock));
parent = aa_deref_parent(ent->new);
newest = aa_get_newest_profile(parent);
/* parent replaced in this atomic set? */
@ -1144,10 +1189,16 @@ ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace)
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
} 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);

View file

@ -37,7 +37,7 @@ int aa_getprocattr(struct aa_profile *profile, char **string)
{
char *str;
int len = 0, mode_len = 0, ns_len = 0, name_len;
const char *mode_str = profile_mode_names[profile->mode];
const char *mode_str = aa_profile_mode_names[profile->mode];
const char *ns_name = NULL;
struct aa_namespace *ns = profile->ns;
struct aa_namespace *current_ns = __aa_current_profile()->ns;