IMA: create machine owner and blacklist keyrings

This option creates IMA MOK and blacklist keyrings.  IMA MOK is an
intermediate keyring that sits between .system and .ima keyrings,
effectively forming a simple CA hierarchy.  To successfully import a key
into .ima_mok it must be signed by a key which CA is in .system keyring.
On turn any key that needs to go in .ima keyring must be signed by CA in
either .system or .ima_mok keyrings. IMA MOK is empty at kernel boot.

IMA blacklist keyring contains all revoked IMA keys.  It is consulted
before any other keyring.  If the search is successful the requested
operation is rejected and error is returned to the caller.

Signed-off-by: Petko Manolov <petkan@mip-labs.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

1 files changed, 54 insertions, 0 deletions

diff --git a/security/integrity/ima/ima_mok.c b/security/integrity/ima/ima_mok.c
new file mode 100644
index 000000000000..18e37f57f512
--- /dev/null
+++ b/security/integrity/ima/ima_mok.c
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2015 Juniper Networks, Inc.
+ *
+ * Author:
+ * Petko Manolov <petko.manolov@konsulko.com>
+ *
+ * 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.
+ *
+ */
+
+#include <linux/export.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/cred.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <keys/asymmetric-type.h>
+
+
+struct key *ima_mok_keyring;
+struct key *ima_blacklist_keyring;
+
+/*
+ * Allocate the IMA MOK and blacklist keyrings
+ */
+__init int ima_mok_init(void)
+{
+	pr_notice("Allocating IMA MOK and blacklist keyrings.\n");
+
+	ima_mok_keyring = keyring_alloc(".ima_mok",
+			      KUIDT_INIT(0), KGIDT_INIT(0), current_cred(),
+			      (KEY_POS_ALL & ~KEY_POS_SETATTR) |
+			      KEY_USR_VIEW | KEY_USR_READ |
+			      KEY_USR_WRITE | KEY_USR_SEARCH,
+			      KEY_ALLOC_NOT_IN_QUOTA, NULL);
+
+	ima_blacklist_keyring = keyring_alloc(".ima_blacklist",
+				KUIDT_INIT(0), KGIDT_INIT(0), current_cred(),
+				(KEY_POS_ALL & ~KEY_POS_SETATTR) |
+				KEY_USR_VIEW | KEY_USR_READ |
+				KEY_USR_WRITE | KEY_USR_SEARCH,
+				KEY_ALLOC_NOT_IN_QUOTA, NULL);
+
+	if (IS_ERR(ima_mok_keyring) || IS_ERR(ima_blacklist_keyring))
+		panic("Can't allocate IMA MOK or blacklist keyrings.");
+	set_bit(KEY_FLAG_TRUSTED_ONLY, &ima_mok_keyring->flags);
+	set_bit(KEY_FLAG_TRUSTED_ONLY, &ima_blacklist_keyring->flags);
+	return 0;
+}
+
+module_init(ima_mok_init);