apparmor: provide finer control over policy management

Signed-off-by: John Johansen <john.johansen@canonical.com>
This commit is contained in:
John Johansen 2017-05-26 01:45:08 -07:00
parent e53cfe6c7c
commit 18e99f191a
3 changed files with 35 additions and 23 deletions

View File

@ -400,17 +400,16 @@ static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf,
return data;
}
static ssize_t policy_update(int binop, const char __user *buf, size_t size,
static ssize_t policy_update(u32 mask, const char __user *buf, size_t size,
loff_t *pos, struct aa_ns *ns)
{
ssize_t error;
struct aa_loaddata *data;
struct aa_profile *profile = aa_current_profile();
const char *op = binop == PROF_ADD ? OP_PROF_LOAD : OP_PROF_REPL;
/* high level check about policy management - fine grained in
* below after unpack
*/
error = aa_may_manage_policy(profile, ns, op);
error = aa_may_manage_policy(profile, ns, mask);
if (error)
return error;
@ -418,7 +417,7 @@ static ssize_t policy_update(int binop, const char __user *buf, size_t size,
error = PTR_ERR(data);
if (!IS_ERR(data)) {
error = aa_replace_profiles(ns ? ns : profile->ns, profile,
binop, data);
mask, data);
aa_put_loaddata(data);
}
@ -430,7 +429,7 @@ static ssize_t profile_load(struct file *f, const char __user *buf, size_t size,
loff_t *pos)
{
struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
int error = policy_update(PROF_ADD, buf, size, pos, ns);
int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns);
aa_put_ns(ns);
@ -447,8 +446,8 @@ static ssize_t profile_replace(struct file *f, const char __user *buf,
size_t size, loff_t *pos)
{
struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
int error = policy_update(PROF_REPLACE, buf, size, pos, ns);
int error = policy_update(AA_MAY_LOAD_POLICY | AA_MAY_REPLACE_POLICY,
buf, size, pos, ns);
aa_put_ns(ns);
return error;
@ -472,7 +471,7 @@ static ssize_t profile_remove(struct file *f, const char __user *buf,
/* high level check about policy management - fine grained in
* below after unpack
*/
error = aa_may_manage_policy(profile, ns, OP_PROF_RM);
error = aa_may_manage_policy(profile, ns, AA_MAY_REMOVE_POLICY);
if (error)
goto out;

View File

@ -188,6 +188,10 @@ struct aa_profile {
extern enum profile_mode aa_g_profile_mode;
#define AA_MAY_LOAD_POLICY AA_MAY_APPEND
#define AA_MAY_REPLACE_POLICY AA_MAY_WRITE
#define AA_MAY_REMOVE_POLICY AA_MAY_DELETE
void __aa_update_proxy(struct aa_profile *orig, struct aa_profile *new);
void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
@ -208,7 +212,7 @@ struct aa_profile *aa_fqlookupn_profile(struct aa_profile *base,
struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name);
ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
bool noreplace, struct aa_loaddata *udata);
u32 mask, struct aa_loaddata *udata);
ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_profile *profile,
char *name, size_t size);
void __aa_profile_list_release(struct list_head *head);
@ -323,6 +327,6 @@ static inline int AUDIT_MODE(struct aa_profile *profile)
bool policy_view_capable(struct aa_ns *ns);
bool policy_admin_capable(struct aa_ns *ns);
int aa_may_manage_policy(struct aa_profile *profile, struct aa_ns *ns,
const char *op);
u32 mask);
#endif /* __AA_POLICY_H */

View File

@ -690,17 +690,25 @@ bool policy_admin_capable(struct aa_ns *ns)
*
* Returns: 0 if the task is allowed to manipulate policy else error
*/
int aa_may_manage_policy(struct aa_profile *profile, struct aa_ns *ns,
const char *op)
int aa_may_manage_policy(struct aa_profile *profile, struct aa_ns *ns, u32 mask)
{
const char *op;
if (mask & AA_MAY_REMOVE_POLICY)
op = OP_PROF_RM;
else if (mask & AA_MAY_REPLACE_POLICY)
op = OP_PROF_REPL;
else
op = OP_PROF_LOAD;
/* check if loading policy is locked out */
if (aa_g_lock_policy)
return audit_policy(profile, op, NULL, NULL,
"policy_locked", -EACCES);
return audit_policy(profile, op, NULL, NULL, "policy_locked",
-EACCES);
if (!policy_admin_capable(ns))
return audit_policy(profile, op, NULL, NULL,
"not policy admin", -EACCES);
return audit_policy(profile, op, NULL, NULL, "not policy admin",
-EACCES);
/* TODO: add fine grained mediation of policy loads */
return 0;
@ -825,7 +833,7 @@ static int __lookup_replace(struct aa_ns *ns, const char *hname,
* aa_replace_profiles - replace profile(s) on the profile list
* @view: namespace load is viewed from
* @label: label that is attempting to load/replace policy
* @noreplace: true if only doing addition, no replacement allowed
* @mask: permission mask
* @udata: serialized data stream (NOT NULL)
*
* unpack and replace a profile on the profile list and uses of that profile
@ -835,17 +843,17 @@ static int __lookup_replace(struct aa_ns *ns, const char *hname,
* Returns: size of data consumed else error code on failure.
*/
ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
bool noreplace, struct aa_loaddata *udata)
u32 mask, struct aa_loaddata *udata)
{
const char *ns_name, *info = NULL;
struct aa_ns *ns = NULL;
struct aa_load_ent *ent, *tmp;
struct aa_loaddata *rawdata_ent;
const char *op = OP_PROF_REPL;
const char *op;
ssize_t count, error;
LIST_HEAD(lh);
op = mask & AA_MAY_REPLACE_POLICY ? OP_PROF_REPL : OP_PROF_LOAD;
aa_get_loaddata(udata);
/* released below */
error = aa_unpack(udata, &lh, &ns_name);
@ -909,15 +917,16 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
struct aa_policy *policy;
ent->new->rawdata = aa_get_loaddata(udata);
error = __lookup_replace(ns, ent->new->base.hname, noreplace,
error = __lookup_replace(ns, ent->new->base.hname,
!(mask & AA_MAY_REPLACE_POLICY),
&ent->old, &info);
if (error)
goto fail_lock;
if (ent->new->rename) {
error = __lookup_replace(ns, ent->new->rename,
noreplace, &ent->rename,
&info);
!(mask & AA_MAY_REPLACE_POLICY),
&ent->rename, &info);
if (error)
goto fail_lock;
}