Merge branch 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity

Pull IMA updates from Mimi Zohar:
 "Two new features - measuring certificates and querying IMA for a file
  hash - and three bug fixes:

   - Measuring certificates is like the rest of IMA, based on policy,
     but requires loading a custom policy. Certificates loaded onto a
     keyring, for example during early boot, before a custom policy has
     been loaded, are queued and only processed after loading the custom
     policy.

   - IMA calculates and caches files hashes. Other kernel subsystems,
     and possibly kernel modules, are interested in accessing these
     cached file hashes.

  The bug fixes prevent classifying a file short read (e.g. shutdown) as
  an invalid file signature, add a missing blank when displaying the
  securityfs policy rules containing LSM labels, and, lastly, fix the
  handling of the IMA policy information for unknown LSM labels"

* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
  IMA: Defined delayed workqueue to free the queued keys
  IMA: Call workqueue functions to measure queued keys
  IMA: Define workqueue for early boot key measurements
  IMA: pre-allocate buffer to hold keyrings string
  ima: ima/lsm policy rule loading logic bug fixes
  ima: add the ability to query the cached hash of a given file
  ima: Add a space after printing LSM rules for readability
  IMA: fix measuring asymmetric keys Kconfig
  IMA: Read keyrings= option from the IMA policy
  IMA: Add support to limit measuring keys
  KEYS: Call the IMA hook to measure keys
  IMA: Define an IMA hook to measure keys
  IMA: Add KEY_CHECK func to measure keys
  IMA: Check IMA policy flag
  ima: avoid appraise error for hash calc interrupt

1 files changed, 66 insertions, 0 deletions

diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c
new file mode 100644
index 000000000000..7678f0e3e84d
--- /dev/null
+++ b/security/integrity/ima/ima_asymmetric_keys.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019 Microsoft Corporation
+ *
+ * Author: Lakshmi Ramasubramanian (nramas@linux.microsoft.com)
+ *
+ * File: ima_asymmetric_keys.c
+ *       Defines an IMA hook to measure asymmetric keys on key
+ *       create or update.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <keys/asymmetric-type.h>
+#include "ima.h"
+
+/**
+ * ima_post_key_create_or_update - measure asymmetric keys
+ * @keyring: keyring to which the key is linked to
+ * @key: created or updated key
+ * @payload: The data used to instantiate or update the key.
+ * @payload_len: The length of @payload.
+ * @flags: key flags
+ * @create: flag indicating whether the key was created or updated
+ *
+ * Keys can only be measured, not appraised.
+ * The payload data used to instantiate or update the key is measured.
+ */
+void ima_post_key_create_or_update(struct key *keyring, struct key *key,
+				   const void *payload, size_t payload_len,
+				   unsigned long flags, bool create)
+{
+	bool queued = false;
+
+	/* Only asymmetric keys are handled by this hook. */
+	if (key->type != &key_type_asymmetric)
+		return;
+
+	if (!payload || (payload_len == 0))
+		return;
+
+	if (ima_should_queue_key())
+		queued = ima_queue_key(keyring, payload, payload_len);
+
+	if (queued)
+		return;
+
+	/*
+	 * keyring->description points to the name of the keyring
+	 * (such as ".builtin_trusted_keys", ".ima", etc.) to
+	 * which the given key is linked to.
+	 *
+	 * The name of the keyring is passed in the "eventname"
+	 * parameter to process_buffer_measurement() and is set
+	 * in the "eventname" field in ima_event_data for
+	 * the key measurement IMA event.
+	 *
+	 * The name of the keyring is also passed in the "keyring"
+	 * parameter to process_buffer_measurement() to check
+	 * if the IMA policy is configured to measure a key linked
+	 * to the given keyring.
+	 */
+	process_buffer_measurement(payload, payload_len,
+				   keyring->description, KEY_CHECK, 0,
+				   keyring->description);
+}