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From 2d13b4094bb5a6d588ba1b155abc96ee094b7af8 Mon Sep 17 00:00:00 2001
From: David Howells <dhowells@redhat.com>
Date: Thu, 3 Aug 2017 16:17:45 +0100
Subject: [PATCH 1/6] KEYS: Allow unrestricted boot-time addition of keys to
 secondary keyring

Patch-mainline: Queued in subsystem maintainer repository
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
Git-commit: 2d13b4094bb5a6d588ba1b155abc96ee094b7af8
References: fate#314508

Allow keys to be added to the system secondary certificates keyring during
kernel initialisation in an unrestricted fashion.  Such keys are implicitly
trusted and don't have their trust chains checked on link.

This allows keys in the UEFI database to be added in secure boot mode for
the purposes of module signing.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
 certs/internal.h       |   18 ++++++++++++++++++
 certs/system_keyring.c |   33 +++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 certs/internal.h

--- /dev/null
+++ b/certs/internal.h
@@ -0,0 +1,18 @@
+/* Internal definitions
+ *
+ * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+/*
+ * system_keyring.c
+ */
+#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
+extern void __init add_trusted_secondary_key(const char *source,
+					     const void *data, size_t len);
+#endif
--- a/certs/system_keyring.c
+++ b/certs/system_keyring.c
@@ -18,6 +18,7 @@
 #include <keys/asymmetric-type.h>
 #include <keys/system_keyring.h>
 #include <crypto/pkcs7.h>
+#include "internal.h"
 
 static struct key *builtin_trusted_keys;
 #ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
@@ -265,3 +266,35 @@ error:
 EXPORT_SYMBOL_GPL(verify_pkcs7_signature);
 
 #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */
+
+#ifdef CONFIG_SECONDARY_TRUSTED_KEYRING
+/**
+ * add_trusted_secondary_key - Add to secondary keyring with no validation
+ * @source: Source of key
+ * @data: The blob holding the key
+ * @len: The length of the data blob
+ *
+ * Add a key to the secondary keyring without checking its trust chain.  This
+ * is available only during kernel initialisation.
+ */
+void __init add_trusted_secondary_key(const char *source,
+				      const void *data, size_t len)
+{
+	key_ref_t key;
+
+	key = key_create_or_update(make_key_ref(secondary_trusted_keys, 1),
+				   "asymmetric",
+				   NULL, data, len,
+				   (KEY_POS_ALL & ~KEY_POS_SETATTR) |
+				   KEY_USR_VIEW,
+				   KEY_ALLOC_NOT_IN_QUOTA |
+				   KEY_ALLOC_BYPASS_RESTRICTION);
+
+	if (IS_ERR(key))
+		pr_err("Problem loading %s X.509 certificate (%ld)\n",
+		       source, PTR_ERR(key));
+	else
+		pr_notice("Loaded %s cert '%s' linked to secondary sys keyring\n",
+			  source, key_ref_to_ptr(key)->description);
+}
+#endif /* CONFIG_SECONDARY_TRUSTED_KEYRING */