Add security hooks that will allow an LSM to rule on whether or not a watch
may be set. More than one hook is required as the watches watch different
types of object.
Signed-off-by: David Howells <dhowe...@redhat.com>
cc: Casey Schaufler <ca...@schaufler-ca.com>
cc: Stephen Smalley <s...@tycho.nsa.gov>
cc: linux-security-mod...@vger.kernel.org
---
include/linux/lsm_hooks.h | 22 ++++++++++++++++++++++
include/linux/security.h | 15 +++++++++++++++
security/security.c | 13 +++++++++++++
3 files changed, 50 insertions(+)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 47f58cfb6a19..f9d31f6445e4 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1413,6 +1413,20 @@
* @ctx is a pointer in which to place the allocated security context.
* @ctxlen points to the place to put the length of @ctx.
*
+ * Security hooks for the general notification queue:
+ *
+ * @watch_key:
+ * Check to see if a process is allowed to watch for event notifications
+ * from a key or keyring.
+ * @watch: The watch object
+ * @key: The key to watch.
+ *
+ * @watch_devices:
+ * Check to see if a process is allowed to watch for event notifications
+ * from devices (as a global set).
+ * @watch: The watch object
+ *
+ *
* Security hooks for using the eBPF maps and programs functionalities through
* eBPF syscalls.
*
@@ -1688,6 +1702,10 @@ union security_list_options {
int (*inode_notifysecctx)(struct inode *inode, void *ctx, u32 ctxlen);
int (*inode_setsecctx)(struct dentry *dentry, void *ctx, u32 ctxlen);
int (*inode_getsecctx)(struct inode *inode, void **ctx, u32 *ctxlen);
+#ifdef CONFIG_WATCH_QUEUE
+ int (*watch_key)(struct watch *watch, struct key *key);
+ int (*watch_devices)(struct watch *watch);
+#endif /* CONFIG_WATCH_QUEUE */
#ifdef CONFIG_SECURITY_NETWORK
int (*unix_stream_connect)(struct sock *sock, struct sock *other,
@@ -1964,6 +1982,10 @@ struct security_hook_heads {
struct hlist_head inode_notifysecctx;
struct hlist_head inode_setsecctx;
struct hlist_head inode_getsecctx;
+#ifdef CONFIG_WATCH_QUEUE
+ struct hlist_head watch_key;
+ struct hlist_head watch_devices;
+#endif /* CONFIG_WATCH_QUEUE */
#ifdef CONFIG_SECURITY_NETWORK
struct hlist_head unix_stream_connect;
struct hlist_head unix_may_send;
diff --git a/include/linux/security.h b/include/linux/security.h
index 659071c2e57c..540863678355 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -57,6 +57,7 @@ struct mm_struct;
struct fs_context;
struct fs_parameter;
enum fs_value_type;
+struct watch;
/* Default (no) options for the capable function */
#define CAP_OPT_NONE 0x0
@@ -392,6 +393,10 @@ void security_inode_invalidate_secctx(struct inode *inode);
int security_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen);
int security_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen);
int security_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen);
+#ifdef CONFIG_WATCH_QUEUE
+int security_watch_key(struct watch *watch, struct key *key);
+int security_watch_devices(struct watch *watch);
+#endif /* CONFIG_WATCH_QUEUE */
#else /* CONFIG_SECURITY */
static inline int call_lsm_notifier(enum lsm_event event, void *data)
@@ -1204,6 +1209,16 @@ static inline int security_inode_getsecctx(struct inode
*inode, void **ctx, u32
{
return -EOPNOTSUPP;
}
+#ifdef CONFIG_WATCH_QUEUE
+static inline int security_watch_key(struct watch *watch, struct key *key)
+{
+ return 0;
+}
+static inline int security_watch_devices(struct watch *watch)
+{
+ return 0;
+}
+#endif /* CONFIG_WATCH_QUEUE */
#endif /* CONFIG_SECURITY */
#ifdef CONFIG_SECURITY_NETWORK
diff --git a/security/security.c b/security/security.c
index 613a5c00e602..2c9919226ad1 100644
--- a/security/security.c
+++ b/security/security.c
@@ -1917,6 +1917,19 @@ int security_inode_getsecctx(struct inode *inode, void
**ctx, u32 *ctxlen)
}
EXPORT_SYMBOL(security_inode_getsecctx);
+#ifdef CONFIG_WATCH_QUEUE
+int security_watch_key(struct watch *watch, struct key *key)
+{
+ return call_int_hook(watch_key, 0, watch, key);
+}
+
+int security_watch_devices(struct watch *watch)
+{
+ return call_int_hook(watch_devices, 0, watch);
+}
+
+#endif /* CONFIG_WATCH_QUEUE */
+
#ifdef CONFIG_SECURITY_NETWORK
int security_unix_stream_connect(struct sock *sock, struct sock *other, struct
sock *newsk)
