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Diffstat (limited to 'security/smack/smack_lsm.c')
-rw-r--r--security/smack/smack_lsm.c112
1 files changed, 104 insertions, 8 deletions
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index cd44b79bf1f5..8ffbf951b7ed 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -41,6 +41,7 @@
#include <linux/parser.h>
#include <linux/fs_context.h>
#include <linux/fs_parser.h>
+#include <linux/watch_queue.h>
#include "smack.h"
#define TRANS_TRUE "TRUE"
@@ -4213,13 +4214,14 @@ static void smack_key_free(struct key *key)
* smack_key_permission - Smack access on a key
* @key_ref: gets to the object
* @cred: the credentials to use
- * @perm: requested key permissions
+ * @need_perm: requested key permission
*
* Return 0 if the task has read and write to the object,
* an error code otherwise
*/
static int smack_key_permission(key_ref_t key_ref,
- const struct cred *cred, unsigned perm)
+ const struct cred *cred,
+ enum key_need_perm need_perm)
{
struct key *keyp;
struct smk_audit_info ad;
@@ -4230,8 +4232,26 @@ static int smack_key_permission(key_ref_t key_ref,
/*
* Validate requested permissions
*/
- if (perm & ~KEY_NEED_ALL)
+ switch (need_perm) {
+ case KEY_NEED_READ:
+ case KEY_NEED_SEARCH:
+ case KEY_NEED_VIEW:
+ request |= MAY_READ;
+ break;
+ case KEY_NEED_WRITE:
+ case KEY_NEED_LINK:
+ case KEY_NEED_SETATTR:
+ request |= MAY_WRITE;
+ break;
+ case KEY_NEED_UNSPECIFIED:
+ case KEY_NEED_UNLINK:
+ case KEY_SYSADMIN_OVERRIDE:
+ case KEY_AUTHTOKEN_OVERRIDE:
+ case KEY_DEFER_PERM_CHECK:
+ return 0;
+ default:
return -EINVAL;
+ }
keyp = key_ref_to_ptr(key_ref);
if (keyp == NULL)
@@ -4248,7 +4268,7 @@ static int smack_key_permission(key_ref_t key_ref,
if (tkp == NULL)
return -EACCES;
- if (smack_privileged_cred(CAP_MAC_OVERRIDE, cred))
+ if (smack_privileged(CAP_MAC_OVERRIDE))
return 0;
#ifdef CONFIG_AUDIT
@@ -4256,10 +4276,6 @@ static int smack_key_permission(key_ref_t key_ref,
ad.a.u.key_struct.key = keyp->serial;
ad.a.u.key_struct.key_desc = keyp->description;
#endif
- if (perm & (KEY_NEED_READ | KEY_NEED_SEARCH | KEY_NEED_VIEW))
- request |= MAY_READ;
- if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR))
- request |= MAY_WRITE;
rc = smk_access(tkp, keyp->security, request, &ad);
rc = smk_bu_note("key access", tkp, keyp->security, request, rc);
return rc;
@@ -4294,8 +4310,81 @@ static int smack_key_getsecurity(struct key *key, char **_buffer)
return length;
}
+
+#ifdef CONFIG_KEY_NOTIFICATIONS
+/**
+ * smack_watch_key - Smack access to watch a key for notifications.
+ * @key: The key to be watched
+ *
+ * Return 0 if the @watch->cred has permission to read from the key object and
+ * an error otherwise.
+ */
+static int smack_watch_key(struct key *key)
+{
+ struct smk_audit_info ad;
+ struct smack_known *tkp = smk_of_current();
+ int rc;
+
+ if (key == NULL)
+ return -EINVAL;
+ /*
+ * If the key hasn't been initialized give it access so that
+ * it may do so.
+ */
+ if (key->security == NULL)
+ return 0;
+ /*
+ * This should not occur
+ */
+ if (tkp == NULL)
+ return -EACCES;
+
+ if (smack_privileged_cred(CAP_MAC_OVERRIDE, current_cred()))
+ return 0;
+
+#ifdef CONFIG_AUDIT
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY);
+ ad.a.u.key_struct.key = key->serial;
+ ad.a.u.key_struct.key_desc = key->description;
+#endif
+ rc = smk_access(tkp, key->security, MAY_READ, &ad);
+ rc = smk_bu_note("key watch", tkp, key->security, MAY_READ, rc);
+ return rc;
+}
+#endif /* CONFIG_KEY_NOTIFICATIONS */
#endif /* CONFIG_KEYS */
+#ifdef CONFIG_WATCH_QUEUE
+/**
+ * smack_post_notification - Smack access to post a notification to a queue
+ * @w_cred: The credentials of the watcher.
+ * @cred: The credentials of the event source (may be NULL).
+ * @n: The notification message to be posted.
+ */
+static int smack_post_notification(const struct cred *w_cred,
+ const struct cred *cred,
+ struct watch_notification *n)
+{
+ struct smk_audit_info ad;
+ struct smack_known *subj, *obj;
+ int rc;
+
+ /* Always let maintenance notifications through. */
+ if (n->type == WATCH_TYPE_META)
+ return 0;
+
+ if (!cred)
+ return 0;
+ subj = smk_of_task(smack_cred(cred));
+ obj = smk_of_task(smack_cred(w_cred));
+
+ smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_NOTIFICATION);
+ rc = smk_access(subj, obj, MAY_WRITE, &ad);
+ rc = smk_bu_note("notification", subj, obj, MAY_WRITE, rc);
+ return rc;
+}
+#endif /* CONFIG_WATCH_QUEUE */
+
/*
* Smack Audit hooks
*
@@ -4684,8 +4773,15 @@ static struct security_hook_list smack_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(key_free, smack_key_free),
LSM_HOOK_INIT(key_permission, smack_key_permission),
LSM_HOOK_INIT(key_getsecurity, smack_key_getsecurity),
+#ifdef CONFIG_KEY_NOTIFICATIONS
+ LSM_HOOK_INIT(watch_key, smack_watch_key),
+#endif
#endif /* CONFIG_KEYS */
+#ifdef CONFIG_WATCH_QUEUE
+ LSM_HOOK_INIT(post_notification, smack_post_notification),
+#endif
+
/* Audit hooks */
#ifdef CONFIG_AUDIT
LSM_HOOK_INIT(audit_rule_init, smack_audit_rule_init),