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* [PATCH v7 0/5] KEYS: Measure keys when they are created or updated
@ 2019-11-14  3:11 Lakshmi Ramasubramanian
  2019-11-14  3:11 ` [PATCH v7 1/5] IMA: Add KEY_CHECK func to measure keys Lakshmi Ramasubramanian
                   ` (4 more replies)
  0 siblings, 5 replies; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14  3:11 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

Keys created or updated in the system are currently not measured.
Therefore an attestation service, for instance, would not be able to
attest whether or not the trusted keys keyring(s), for instance, contain
only known good (trusted) keys.

IMA measures system files, command line arguments passed to kexec,
boot aggregate, etc. It can be used to measure keys as well.
But there is no mechanism available in the kernel for IMA to
know when a key is created or updated.

This change aims to address measuring keys created or updated
in the system.

To achieve the above the following changes have been made:

 - Added a new IMA hook namely, ima_post_key_create_or_update, which
   measures the key. This IMA hook is called from key_create_or_update
   function. The key measurement can be controlled through IMA policy.

   A new IMA policy function KEY_CHECK has been added to measure keys.
   "keyrings=" option can be specified for KEY_CHECK to limit
   measuring the keys loaded onto the specified keyrings only.

   # measure keys loaded onto any keyring
   measure func=KEY_CHECK

   # measure keys loaded onto the IMA keyring only
   measure func=KEY_CHECK keyring=".ima"

   # measure keys on the BUILTIN and IMA keyrings into a different PCR
   measure func=KEY_CHECK keyring=".builtin_trusted_keys|.ima" pcr=11

Testing performed:

  * Booted the kernel with this change.
  * When KEY_CHECK policy is set IMA measures keys loaded
    onto any keyring (keyrings= option not specified).
  * Keys are not measured when KEY_CHECK is not set.
  * When keyrings= option is specified for KEY_CHECK then only the keys
    loaded onto a keyring specified in the option is measured.
  * Added a new key to a keyring.
    => Added keys to .ima and .evm keyrings.
  * Added the same key again.
    => Add the same key to .ima and .evm keyrings.

Change Log:

  v7:

  => Removed CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS option and used
     CONFIG_KEYS instead for ima_asymmetric_keys.c
  => Added the patches related to "keyrings=" option support to
     this patch set.

  v6:

  => Rebased the changes to v5.4-rc7
  => Renamed KEYRING_CHECK to KEY_CHECK per Mimi's suggestion.
  => Excluded the patches that add support for limiting key
     measurement to specific keyrings ("keyrings=" option
     for "measure func=KEY_CHECK" in the IMA policy).
     Also, excluded the patches that add support for deferred
     processing of keys (queue support).
     These patches will be added in separate patch sets later.

  v5:

  => Reorganized the patches to add measurement of keys through
     the IMA hook without any queuing and then added queuing support.
  => Updated the queuing functions to minimize code executed inside mutex.
  => Process queued keys after custom IMA policies have been applied.

  v4:

  => Rebased the changes to v5.4-rc3
  => Applied the following dependent patch set first
     and then added new changes.
  https://lore.kernel.org/linux-integrity/1572492694-6520-1-git-send-email-zohar@linux.ibm.com
  => Refactored the patch set to separate out changes related to
     func KEYRING_CHECK and options keyrings into different patches.
  => Moved the functions to queue and dequeue keys for measurement
     from ima_queue.c to a new file ima_asymmetric_keys.c.
  => Added a new config namely CONFIG_IMA_MEASURE_ASYMMETRIC_KEYS
     to compile ima_asymmetric_keys.c

  v3:

  => Added KEYRING_CHECK for measuring keys. This can optionally specify
     keyrings to measure.
  => Updated ima_get_action() and related functions to return
     the keyrings if specified in the policy.
  => process_buffer_measurement() function is updated to take keyring
     as a parameter. The key will be measured if the policy includes
     the keyring in the list of measured keyrings. If the policy does not
     specify any keyrings then all keys are measured.

  v2:

  => Per suggestion from Mimi reordered the patch set to first
     enable measuring keys added or updated in the system.
     And, then scope the measurement to keys added to 
     builtin_trusted_keys keyring through ima policy.
  => Removed security_key_create_or_update function and instead
     call ima hook, to measure the key, directly from 
     key_create_or_update function.

  v1:

  => LSM function for key_create_or_update. It calls ima.
  => Added ima hook for measuring keys
  => ima measures keys based on ima policy.

  v0:

  => Added LSM hook for key_create_or_update.
  => Measure keys added to builtin or secondary trusted keys keyring.

Lakshmi Ramasubramanian (5):
  IMA: Add KEY_CHECK func to measure keys
  IMA: Define an IMA hook to measure keys
  KEYS: Call the IMA hook to measure keys
  IMA: Add support to limit measuring keys
  IMA: Read keyrings= option from the IMA policy

 Documentation/ABI/testing/ima_policy         | 17 ++++-
 include/linux/ima.h                          | 13 ++++
 security/integrity/ima/Makefile              |  1 +
 security/integrity/ima/ima.h                 |  9 ++-
 security/integrity/ima/ima_api.c             |  8 ++-
 security/integrity/ima/ima_appraise.c        |  4 +-
 security/integrity/ima/ima_asymmetric_keys.c | 57 ++++++++++++++++
 security/integrity/ima/ima_main.c            |  9 +--
 security/integrity/ima/ima_policy.c          | 70 ++++++++++++++++++--
 security/keys/key.c                          |  7 ++
 10 files changed, 175 insertions(+), 20 deletions(-)
 create mode 100644 security/integrity/ima/ima_asymmetric_keys.c

-- 
2.17.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v7 1/5] IMA: Add KEY_CHECK func to measure keys
  2019-11-14  3:11 [PATCH v7 0/5] KEYS: Measure keys when they are created or updated Lakshmi Ramasubramanian
@ 2019-11-14  3:11 ` Lakshmi Ramasubramanian
  2019-11-14  3:11 ` [PATCH v7 2/5] IMA: Define an IMA hook " Lakshmi Ramasubramanian
                   ` (3 subsequent siblings)
  4 siblings, 0 replies; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14  3:11 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

Measure keys loaded onto any keyring.

This patch defines a new IMA policy func namely KEY_CHECK to
measure keys. Updated ima_match_rules() to check for KEY_CHECK
and ima_parse_rule() to handle KEY_CHECK.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 Documentation/ABI/testing/ima_policy | 7 ++++++-
 security/integrity/ima/ima.h         | 1 +
 security/integrity/ima/ima_policy.c  | 4 +++-
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
index 29aaedf33246..3823c27894c5 100644
--- a/Documentation/ABI/testing/ima_policy
+++ b/Documentation/ABI/testing/ima_policy
@@ -29,7 +29,7 @@ Description:
 		base: 	func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK]
 				[FIRMWARE_CHECK]
 				[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
-				[KEXEC_CMDLINE]
+				[KEXEC_CMDLINE] [KEY_CHECK]
 			mask:= [[^]MAY_READ] [[^]MAY_WRITE] [[^]MAY_APPEND]
 			       [[^]MAY_EXEC]
 			fsmagic:= hex value
@@ -113,3 +113,8 @@ Description:
 		Example of appraise rule allowing modsig appended signatures:
 
 			appraise func=KEXEC_KERNEL_CHECK appraise_type=imasig|modsig
+
+		Example of measure rule using KEY_CHECK to measure all keys:
+
+			measure func=KEY_CHECK
+
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index df4ca482fb53..fe6c698617bd 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -193,6 +193,7 @@ static inline unsigned long ima_hash_key(u8 *digest)
 	hook(KEXEC_INITRAMFS_CHECK)	\
 	hook(POLICY_CHECK)		\
 	hook(KEXEC_CMDLINE)		\
+	hook(KEY_CHECK)			\
 	hook(MAX_CHECK)
 #define __ima_hook_enumify(ENUM)	ENUM,
 
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index f19a895ad7cd..1525a28fd705 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -373,7 +373,7 @@ static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
 {
 	int i;
 
-	if (func == KEXEC_CMDLINE) {
+	if ((func == KEXEC_CMDLINE) || (func == KEY_CHECK)) {
 		if ((rule->flags & IMA_FUNC) && (rule->func == func))
 			return true;
 		return false;
@@ -997,6 +997,8 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 				entry->func = POLICY_CHECK;
 			else if (strcmp(args[0].from, "KEXEC_CMDLINE") == 0)
 				entry->func = KEXEC_CMDLINE;
+			else if (strcmp(args[0].from, "KEY_CHECK") == 0)
+				entry->func = KEY_CHECK;
 			else
 				result = -EINVAL;
 			if (!result)
-- 
2.17.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v7 2/5] IMA: Define an IMA hook to measure keys
  2019-11-14  3:11 [PATCH v7 0/5] KEYS: Measure keys when they are created or updated Lakshmi Ramasubramanian
  2019-11-14  3:11 ` [PATCH v7 1/5] IMA: Add KEY_CHECK func to measure keys Lakshmi Ramasubramanian
@ 2019-11-14  3:11 ` " Lakshmi Ramasubramanian
  2019-11-14 18:30   ` Lakshmi Ramasubramanian
  2019-11-14  3:12 ` [PATCH v7 3/5] KEYS: Call the " Lakshmi Ramasubramanian
                   ` (2 subsequent siblings)
  4 siblings, 1 reply; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14  3:11 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

Measure asymmetric keys used for verifying file signatures,
certificates, etc.

This patch defines a new IMA hook namely ima_post_key_create_or_update()
to measure asymmetric keys.

The IMA hook is defined in a new file namely ima_asymmetric_keys.c
which is built only if CONFIG_KEYS is enabled.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 security/integrity/ima/Makefile              |  1 +
 security/integrity/ima/ima_asymmetric_keys.c | 51 ++++++++++++++++++++
 2 files changed, 52 insertions(+)
 create mode 100644 security/integrity/ima/ima_asymmetric_keys.c

diff --git a/security/integrity/ima/Makefile b/security/integrity/ima/Makefile
index 31d57cdf2421..3c796664be8a 100644
--- a/security/integrity/ima/Makefile
+++ b/security/integrity/ima/Makefile
@@ -12,3 +12,4 @@ ima-$(CONFIG_IMA_APPRAISE) += ima_appraise.o
 ima-$(CONFIG_IMA_APPRAISE_MODSIG) += ima_modsig.o
 ima-$(CONFIG_HAVE_IMA_KEXEC) += ima_kexec.o
 obj-$(CONFIG_IMA_BLACKLIST_KEYRING) += ima_mok.o
+obj-$(CONFIG_KEYS) += ima_asymmetric_keys.o
diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c
new file mode 100644
index 000000000000..f6884641a622
--- /dev/null
+++ b/security/integrity/ima/ima_asymmetric_keys.c
@@ -0,0 +1,51 @@
+// 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 <crypto/public_key.h>
+#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
+ * @flags: key flags
+ * @create: flag indicating whether the key was created or updated
+ *
+ * Keys can only be measured, not appraised.
+ */
+void ima_post_key_create_or_update(struct key *keyring, struct key *key,
+				   unsigned long flags, bool create)
+{
+	const struct public_key *pk;
+
+	/* Only asymmetric keys are handled by this hook. */
+	if (key->type != &key_type_asymmetric)
+		return;
+
+	/* Get the public_key of the given asymmetric key to measure. */
+	pk = key->payload.data[asym_crypto];
+
+	/*
+	 * 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.
+	 */
+	process_buffer_measurement(pk->key, pk->keylen,
+				   keyring->description, KEY_CHECK, 0);
+}
-- 
2.17.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v7 3/5] KEYS: Call the IMA hook to measure keys
  2019-11-14  3:11 [PATCH v7 0/5] KEYS: Measure keys when they are created or updated Lakshmi Ramasubramanian
  2019-11-14  3:11 ` [PATCH v7 1/5] IMA: Add KEY_CHECK func to measure keys Lakshmi Ramasubramanian
  2019-11-14  3:11 ` [PATCH v7 2/5] IMA: Define an IMA hook " Lakshmi Ramasubramanian
@ 2019-11-14  3:12 ` " Lakshmi Ramasubramanian
  2019-11-14 14:54   ` Mimi Zohar
  2019-11-14  3:12 ` [PATCH v7 4/5] IMA: Add support to limit measuring keys Lakshmi Ramasubramanian
  2019-11-14  3:12 ` [PATCH v7 5/5] IMA: Read keyrings= option from the IMA policy Lakshmi Ramasubramanian
  4 siblings, 1 reply; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14  3:12 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

Call the IMA hook from key_create_or_update function to measure
the key when a new key is created or an existing key is updated.

This patch adds the call to the IMA hook from key_create_or_update
function to measure the key on key create or update.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 include/linux/ima.h | 13 +++++++++++++
 security/keys/key.c |  7 +++++++
 2 files changed, 20 insertions(+)

diff --git a/include/linux/ima.h b/include/linux/ima.h
index 6d904754d858..0af88b781ab6 100644
--- a/include/linux/ima.h
+++ b/include/linux/ima.h
@@ -25,6 +25,12 @@ extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
 extern void ima_post_path_mknod(struct dentry *dentry);
 extern void ima_kexec_cmdline(const void *buf, int size);
 
+#ifdef CONFIG_KEYS
+extern void ima_post_key_create_or_update(struct key *keyring,
+					  struct key *key,
+					  unsigned long flags, bool create);
+#endif
+
 #ifdef CONFIG_IMA_KEXEC
 extern void ima_add_kexec_buffer(struct kimage *image);
 #endif
@@ -101,6 +107,13 @@ static inline void ima_add_kexec_buffer(struct kimage *image)
 {}
 #endif
 
+#ifndef CONFIG_KEYS
+static inline void ima_post_key_create_or_update(struct key *keyring,
+						 struct key *key,
+						 unsigned long flags,
+						 bool create) {}
+#endif
+
 #ifdef CONFIG_IMA_APPRAISE
 extern bool is_ima_appraise_enabled(void);
 extern void ima_inode_post_setattr(struct dentry *dentry);
diff --git a/security/keys/key.c b/security/keys/key.c
index 764f4c57913e..a0f1e7b3b8b9 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -13,6 +13,7 @@
 #include <linux/security.h>
 #include <linux/workqueue.h>
 #include <linux/random.h>
+#include <linux/ima.h>
 #include <linux/err.h>
 #include "internal.h"
 
@@ -936,6 +937,8 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 		goto error_link_end;
 	}
 
+	ima_post_key_create_or_update(keyring, key, flags, true);
+
 	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
 
 error_link_end:
@@ -965,6 +968,10 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
 	}
 
 	key_ref = __key_update(key_ref, &prep);
+
+	if (!IS_ERR(key_ref))
+		ima_post_key_create_or_update(keyring, key, flags, false);
+
 	goto error_free_prep;
 }
 EXPORT_SYMBOL(key_create_or_update);
-- 
2.17.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v7 4/5] IMA: Add support to limit measuring keys
  2019-11-14  3:11 [PATCH v7 0/5] KEYS: Measure keys when they are created or updated Lakshmi Ramasubramanian
                   ` (2 preceding siblings ...)
  2019-11-14  3:12 ` [PATCH v7 3/5] KEYS: Call the " Lakshmi Ramasubramanian
@ 2019-11-14  3:12 ` Lakshmi Ramasubramanian
  2019-11-14 14:37   ` Mimi Zohar
  2019-11-14  3:12 ` [PATCH v7 5/5] IMA: Read keyrings= option from the IMA policy Lakshmi Ramasubramanian
  4 siblings, 1 reply; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14  3:12 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

Limit measuring keys to those keys being loaded onto a given set of
keyrings only.

This patch defines a new IMA policy option namely "keyrings=" that
can be used to specify a set of keyrings. If this option is specified
in the policy for "measure func=KEY_CHECK" then only the keys
loaded onto a keyring given in the "keyrings=" option are measured.

Added a new parameter namely "keyring" (name of the keyring) to
process_buffer_measurement(). The keyring name is passed to
ima_get_action() to determine the required action.
ima_match_rules() is updated to check keyring in the policy, if
specified, for KEY_CHECK function.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 Documentation/ABI/testing/ima_policy         | 10 +++++-
 security/integrity/ima/ima.h                 |  8 +++--
 security/integrity/ima/ima_api.c             |  8 +++--
 security/integrity/ima/ima_appraise.c        |  4 +--
 security/integrity/ima/ima_asymmetric_keys.c |  8 ++++-
 security/integrity/ima/ima_main.c            |  9 ++---
 security/integrity/ima/ima_policy.c          | 37 +++++++++++++++++---
 7 files changed, 66 insertions(+), 18 deletions(-)

diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
index 3823c27894c5..5a941ed20fa3 100644
--- a/Documentation/ABI/testing/ima_policy
+++ b/Documentation/ABI/testing/ima_policy
@@ -25,7 +25,7 @@ Description:
 			lsm:	[[subj_user=] [subj_role=] [subj_type=]
 				 [obj_user=] [obj_role=] [obj_type=]]
 			option:	[[appraise_type=]] [template=] [permit_directio]
-				[appraise_flag=]
+				[appraise_flag=] [keyrings=]
 		base: 	func:= [BPRM_CHECK][MMAP_CHECK][CREDS_CHECK][FILE_CHECK][MODULE_CHECK]
 				[FIRMWARE_CHECK]
 				[KEXEC_KERNEL_CHECK] [KEXEC_INITRAMFS_CHECK]
@@ -42,6 +42,9 @@ Description:
 			appraise_flag:= [check_blacklist]
 			Currently, blacklist check is only for files signed with appended
 			signature.
+			keyrings:= list of keyrings
+			(eg, .builtin_trusted_keys|.ima). Only valid
+			when action is "measure" and func is KEY_CHECK.
 			template:= name of a defined IMA template type
 			(eg, ima-ng). Only valid when action is "measure".
 			pcr:= decimal value
@@ -118,3 +121,8 @@ Description:
 
 			measure func=KEY_CHECK
 
+		Example of measure rule using KEY_CHECK to only measure
+		keys added to .builtin_trusted_keys or .ima keyring:
+
+			measure func=KEY_CHECK keyrings=.builtin_trusted_keys|.ima
+
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index fe6c698617bd..f06238e41a7c 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -208,7 +208,8 @@ struct modsig;
 /* LIM API function definitions */
 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
 		   int mask, enum ima_hooks func, int *pcr,
-		   struct ima_template_desc **template_desc);
+		   struct ima_template_desc **template_desc,
+		   const char *keyring);
 int ima_must_measure(struct inode *inode, int mask, enum ima_hooks func);
 int ima_collect_measurement(struct integrity_iint_cache *iint,
 			    struct file *file, void *buf, loff_t size,
@@ -220,7 +221,7 @@ void ima_store_measurement(struct integrity_iint_cache *iint, struct file *file,
 			   struct ima_template_desc *template_desc);
 void process_buffer_measurement(const void *buf, int size,
 				const char *eventname, enum ima_hooks func,
-				int pcr);
+				int pcr, const char *keyring);
 void ima_audit_measurement(struct integrity_iint_cache *iint,
 			   const unsigned char *filename);
 int ima_alloc_init_template(struct ima_event_data *event_data,
@@ -235,7 +236,8 @@ const char *ima_d_path(const struct path *path, char **pathbuf, char *filename);
 /* IMA policy related functions */
 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
 		     enum ima_hooks func, int mask, int flags, int *pcr,
-		     struct ima_template_desc **template_desc);
+		     struct ima_template_desc **template_desc,
+		     const char *keyring);
 void ima_init_policy(void);
 void ima_update_policy(void);
 void ima_update_policy_flag(void);
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 610759fe63b8..f6bc00914aa5 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -169,12 +169,13 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
  * @func: caller identifier
  * @pcr: pointer filled in if matched measure policy sets pcr=
  * @template_desc: pointer filled in if matched measure policy sets template=
+ * @keyring: keyring name used to determine the action
  *
  * The policy is defined in terms of keypairs:
  *		subj=, obj=, type=, func=, mask=, fsmagic=
  *	subj,obj, and type: are LSM specific.
  *	func: FILE_CHECK | BPRM_CHECK | CREDS_CHECK | MMAP_CHECK | MODULE_CHECK
- *	| KEXEC_CMDLINE
+ *	| KEXEC_CMDLINE | KEY_CHECK
  *	mask: contains the permission mask
  *	fsmagic: hex value
  *
@@ -183,14 +184,15 @@ void ima_add_violation(struct file *file, const unsigned char *filename,
  */
 int ima_get_action(struct inode *inode, const struct cred *cred, u32 secid,
 		   int mask, enum ima_hooks func, int *pcr,
-		   struct ima_template_desc **template_desc)
+		   struct ima_template_desc **template_desc,
+		   const char *keyring)
 {
 	int flags = IMA_MEASURE | IMA_AUDIT | IMA_APPRAISE | IMA_HASH;
 
 	flags &= ima_policy_flag;
 
 	return ima_match_policy(inode, cred, secid, func, mask, flags, pcr,
-				template_desc);
+				template_desc, keyring);
 }
 
 /*
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c
index 300c8d2943c5..a9649b04b9f1 100644
--- a/security/integrity/ima/ima_appraise.c
+++ b/security/integrity/ima/ima_appraise.c
@@ -55,7 +55,7 @@ int ima_must_appraise(struct inode *inode, int mask, enum ima_hooks func)
 
 	security_task_getsecid(current, &secid);
 	return ima_match_policy(inode, current_cred(), secid, func, mask,
-				IMA_APPRAISE | IMA_HASH, NULL, NULL);
+				IMA_APPRAISE | IMA_HASH, NULL, NULL, NULL);
 }
 
 static int ima_fix_xattr(struct dentry *dentry,
@@ -330,7 +330,7 @@ int ima_check_blacklist(struct integrity_iint_cache *iint,
 		if ((rc == -EPERM) && (iint->flags & IMA_MEASURE))
 			process_buffer_measurement(digest, digestsize,
 						   "blacklisted-hash", NONE,
-						   pcr);
+						   pcr, NULL);
 	}
 
 	return rc;
diff --git a/security/integrity/ima/ima_asymmetric_keys.c b/security/integrity/ima/ima_asymmetric_keys.c
index f6884641a622..8c692eb08a0a 100644
--- a/security/integrity/ima/ima_asymmetric_keys.c
+++ b/security/integrity/ima/ima_asymmetric_keys.c
@@ -45,7 +45,13 @@ void ima_post_key_create_or_update(struct key *keyring, struct key *key,
 	 * 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(pk->key, pk->keylen,
-				   keyring->description, KEY_CHECK, 0);
+				   keyring->description, KEY_CHECK, 0,
+				   keyring->description);
 }
diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c
index d7e987baf127..6d0bf241ebf8 100644
--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -215,7 +215,7 @@ static int process_measurement(struct file *file, const struct cred *cred,
 	 * Included is the appraise submask.
 	 */
 	action = ima_get_action(inode, cred, secid, mask, func, &pcr,
-				&template_desc);
+				&template_desc, NULL);
 	violation_check = ((func == FILE_CHECK || func == MMAP_CHECK) &&
 			   (ima_policy_flag & IMA_MEASURE));
 	if (!action && !violation_check)
@@ -632,12 +632,13 @@ int ima_load_data(enum kernel_load_data_id id)
  * @eventname: event name to be used for the buffer entry.
  * @func: IMA hook
  * @pcr: pcr to extend the measurement
+ * @keyring: keyring name to determine the action to be performed
  *
  * Based on policy, the buffer is measured into the ima log.
  */
 void process_buffer_measurement(const void *buf, int size,
 				const char *eventname, enum ima_hooks func,
-				int pcr)
+				int pcr, const char *keyring)
 {
 	int ret = 0;
 	struct ima_template_entry *entry = NULL;
@@ -665,7 +666,7 @@ void process_buffer_measurement(const void *buf, int size,
 	if (func) {
 		security_task_getsecid(current, &secid);
 		action = ima_get_action(NULL, current_cred(), secid, 0, func,
-					&pcr, &template);
+					&pcr, &template, keyring);
 		if (!(action & IMA_MEASURE))
 			return;
 	}
@@ -718,7 +719,7 @@ void ima_kexec_cmdline(const void *buf, int size)
 {
 	if (buf && size != 0)
 		process_buffer_measurement(buf, size, "kexec-cmdline",
-					   KEXEC_CMDLINE, 0);
+					   KEXEC_CMDLINE, 0, NULL);
 }
 
 static int __init init_ima(void)
diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 1525a28fd705..76da4f17bc79 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -79,6 +79,7 @@ struct ima_rule_entry {
 		int type;	/* audit type */
 	} lsm[MAX_LSM_RULES];
 	char *fsname;
+	char *keyrings; /* Measure keys added to these keyrings */
 	struct ima_template_desc *template;
 };
 
@@ -356,6 +357,25 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
 	return NOTIFY_OK;
 }
 
+/**
+ * ima_match_keyring - determine whether the keyring matches the measure rule
+ * @rule: a pointer to a rule
+ * @keyring: name of the keyring to match against the measure rule
+ *
+ * If the measure action for KEY_CHECK does not specify keyrings=
+ * option then return true (Measure all keys).
+ * Else, return true if the given keyring name is present in
+ * the keyrings= option. False, otherwise.
+ */
+static bool ima_match_keyring(struct ima_rule_entry *rule,
+			      const char *keyring)
+{
+	if ((keyring == NULL) || (rule->keyrings == NULL))
+		return true;
+	else
+		return (strstr(rule->keyrings, keyring) != NULL);
+}
+
 /**
  * ima_match_rules - determine whether an inode matches the measure rule.
  * @rule: a pointer to a rule
@@ -364,18 +384,23 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
  * @secid: the secid of the task to be validated
  * @func: LIM hook identifier
  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
+ * @keyring: keyring name to check in policy for KEY_CHECK func
  *
  * Returns true on rule match, false on failure.
  */
 static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
 			    const struct cred *cred, u32 secid,
-			    enum ima_hooks func, int mask)
+			    enum ima_hooks func, int mask,
+			    const char *keyring)
 {
 	int i;
 
 	if ((func == KEXEC_CMDLINE) || (func == KEY_CHECK)) {
-		if ((rule->flags & IMA_FUNC) && (rule->func == func))
+		if ((rule->flags & IMA_FUNC) && (rule->func == func)) {
+			if (func == KEY_CHECK)
+				return ima_match_keyring(rule, keyring);
 			return true;
+		}
 		return false;
 	}
 	if ((rule->flags & IMA_FUNC) &&
@@ -479,6 +504,8 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
  * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
  * @pcr: set the pcr to extend
  * @template_desc: the template that should be used for this rule
+ * @keyring: the keyring name, if given, to be used to check in the policy.
+ *           keyring can be NULL if func is anything other than KEY_CHECK.
  *
  * Measure decision based on func/mask/fsmagic and LSM(subj/obj/type)
  * conditions.
@@ -489,7 +516,8 @@ static int get_subaction(struct ima_rule_entry *rule, enum ima_hooks func)
  */
 int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
 		     enum ima_hooks func, int mask, int flags, int *pcr,
-		     struct ima_template_desc **template_desc)
+		     struct ima_template_desc **template_desc,
+		     const char *keyring)
 {
 	struct ima_rule_entry *entry;
 	int action = 0, actmask = flags | (flags << 1);
@@ -503,7 +531,8 @@ int ima_match_policy(struct inode *inode, const struct cred *cred, u32 secid,
 		if (!(entry->action & actmask))
 			continue;
 
-		if (!ima_match_rules(entry, inode, cred, secid, func, mask))
+		if (!ima_match_rules(entry, inode, cred, secid, func, mask,
+				     keyring))
 			continue;
 
 		action |= entry->flags & IMA_ACTION_FLAGS;
-- 
2.17.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH v7 5/5] IMA: Read keyrings= option from the IMA policy
  2019-11-14  3:11 [PATCH v7 0/5] KEYS: Measure keys when they are created or updated Lakshmi Ramasubramanian
                   ` (3 preceding siblings ...)
  2019-11-14  3:12 ` [PATCH v7 4/5] IMA: Add support to limit measuring keys Lakshmi Ramasubramanian
@ 2019-11-14  3:12 ` Lakshmi Ramasubramanian
  4 siblings, 0 replies; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14  3:12 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

Read "keyrings=" option, if specified in the IMA policy, and store in
the list of IMA rules when the configured IMA policy is read.

This patch defines a new policy token enum namely Opt_keyrings
and an option flag IMA_KEYRINGS for reading "keyrings=" option
from the IMA policy.

Updated ima_parse_rule() to parse "keyrings=" option in the policy.
Updated ima_policy_show() to display "keyrings=" option.

Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
---
 security/integrity/ima/ima_policy.c | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c
index 76da4f17bc79..577a51a548fb 100644
--- a/security/integrity/ima/ima_policy.c
+++ b/security/integrity/ima/ima_policy.c
@@ -34,6 +34,7 @@
 #define IMA_EUID	0x0080
 #define IMA_PCR		0x0100
 #define IMA_FSNAME	0x0200
+#define IMA_KEYRINGS	0x0400
 
 #define UNKNOWN		0
 #define MEASURE		0x0001	/* same as IMA_MEASURE */
@@ -795,7 +796,8 @@ enum {
 	Opt_uid_gt, Opt_euid_gt, Opt_fowner_gt,
 	Opt_uid_lt, Opt_euid_lt, Opt_fowner_lt,
 	Opt_appraise_type, Opt_appraise_flag,
-	Opt_permit_directio, Opt_pcr, Opt_template, Opt_err
+	Opt_permit_directio, Opt_pcr, Opt_template, Opt_keyrings,
+	Opt_err
 };
 
 static const match_table_t policy_tokens = {
@@ -831,6 +833,7 @@ static const match_table_t policy_tokens = {
 	{Opt_permit_directio, "permit_directio"},
 	{Opt_pcr, "pcr=%s"},
 	{Opt_template, "template=%s"},
+	{Opt_keyrings, "keyrings=%s"},
 	{Opt_err, NULL}
 };
 
@@ -1080,6 +1083,23 @@ static int ima_parse_rule(char *rule, struct ima_rule_entry *entry)
 			result = 0;
 			entry->flags |= IMA_FSNAME;
 			break;
+		case Opt_keyrings:
+			ima_log_string(ab, "keyrings", args[0].from);
+
+			if ((entry->keyrings) ||
+			    (entry->action != MEASURE) ||
+			    (entry->func != KEY_CHECK)) {
+				result = -EINVAL;
+				break;
+			}
+			entry->keyrings = kstrdup(args[0].from, GFP_KERNEL);
+			if (!entry->keyrings) {
+				result = -ENOMEM;
+				break;
+			}
+			result = 0;
+			entry->flags |= IMA_KEYRINGS;
+			break;
 		case Opt_fsuuid:
 			ima_log_string(ab, "fsuuid", args[0].from);
 
@@ -1455,6 +1475,13 @@ int ima_policy_show(struct seq_file *m, void *v)
 		seq_puts(m, " ");
 	}
 
+	if (entry->flags & IMA_KEYRINGS) {
+		if (entry->keyrings != NULL)
+			snprintf(tbuf, sizeof(tbuf), "%s", entry->keyrings);
+		seq_printf(m, pt(Opt_keyrings), tbuf);
+		seq_puts(m, " ");
+	}
+
 	if (entry->flags & IMA_PCR) {
 		snprintf(tbuf, sizeof(tbuf), "%d", entry->pcr);
 		seq_printf(m, pt(Opt_pcr), tbuf);
-- 
2.17.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v7 4/5] IMA: Add support to limit measuring keys
  2019-11-14  3:12 ` [PATCH v7 4/5] IMA: Add support to limit measuring keys Lakshmi Ramasubramanian
@ 2019-11-14 14:37   ` Mimi Zohar
  2019-11-14 18:18     ` Lakshmi Ramasubramanian
  0 siblings, 1 reply; 12+ messages in thread
From: Mimi Zohar @ 2019-11-14 14:37 UTC (permalink / raw)
  To: Lakshmi Ramasubramanian, dhowells, matthewgarrett, sashal,
	jamorris, linux-integrity, linux-security-module, keyrings,
	linux-kernel

On Wed, 2019-11-13 at 19:12 -0800, Lakshmi Ramasubramanian wrote:
> +/**
> + * ima_match_keyring - determine whether the keyring matches the measure rule
> + * @rule: a pointer to a rule
> + * @keyring: name of the keyring to match against the measure rule
> + *
> + * If the measure action for KEY_CHECK does not specify keyrings=
> + * option then return true (Measure all keys).
> + * Else, return true if the given keyring name is present in
> + * the keyrings= option. False, otherwise.
> + */
> +static bool ima_match_keyring(struct ima_rule_entry *rule,
> +			      const char *keyring)
> +{
> +	if ((keyring == NULL) || (rule->keyrings == NULL)
> +		return true;

If the policy requires matching a specific keyring, then the "keyring"
needs to match.  The logic, here, isn't quite right.

> +	else
> +		return (strstr(rule->keyrings, keyring) != NULL);

    if (rule->keyrings) {
            if (!keyring)
                    return false;
		
            return (strstr(rule->keyrings, keyring) != NULL);
    }

    return true;

Keyrings may be created by userspace with any name (e.g. foo, foobar,
...).  A keyring name might be a subset of another keyring name.  For
example, with the policy "keyrings=foobar", keys being loaded on "foo"
would also be measured.  Using strstr() will not achieve what is
needed.

Mimi


> +}
> +
>  /**
>   * ima_match_rules - determine whether an inode matches the measure rule.
>   * @rule: a pointer to a rule
> @@ -364,18 +384,23 @@ int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
>   * @secid: the secid of the task to be validated
>   * @func: LIM hook identifier
>   * @mask: requested action (MAY_READ | MAY_WRITE | MAY_APPEND | MAY_EXEC)
> + * @keyring: keyring name to check in policy for KEY_CHECK func
>   *
>   * Returns true on rule match, false on failure.
>   */
>  static bool ima_match_rules(struct ima_rule_entry *rule, struct inode *inode,
>  			    const struct cred *cred, u32 secid,
> -			    enum ima_hooks func, int mask)
> +			    enum ima_hooks func, int mask,
> +			    const char *keyring)
>  {
>  	int i;
>  
>  	if ((func == KEXEC_CMDLINE) || (func == KEY_CHECK)) {
> -		if ((rule->flags & IMA_FUNC) && (rule->func == func))
> +		if ((rule->flags & IMA_FUNC) && (rule->func == func)) {
> +			if (func == KEY_CHECK)
> +				return ima_match_keyring(rule, keyring);
>  			return true;
> +		}
>  		return false;
>  	}
>  	if ((rule->flags & IMA_FUNC) &&


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v7 3/5] KEYS: Call the IMA hook to measure keys
  2019-11-14  3:12 ` [PATCH v7 3/5] KEYS: Call the " Lakshmi Ramasubramanian
@ 2019-11-14 14:54   ` Mimi Zohar
  2019-11-14 18:24     ` Lakshmi Ramasubramanian
  0 siblings, 1 reply; 12+ messages in thread
From: Mimi Zohar @ 2019-11-14 14:54 UTC (permalink / raw)
  To: Lakshmi Ramasubramanian, dhowells, matthewgarrett, sashal,
	jamorris, linux-integrity, linux-security-module, keyrings,
	linux-kernel

On Wed, 2019-11-13 at 19:12 -0800, Lakshmi Ramasubramanian wrote:
> Call the IMA hook from key_create_or_update function to measure
> the key when a new key is created or an existing key is updated.
> 
> This patch adds the call to the IMA hook from key_create_or_update
> function to measure the key on key create or update.
> 
> Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>

No need to Cc David Howells on the entire patch set.  Just Cc him,
here, after your tag.

With this patch, keys are now being measured.  With the boot command
line, we can verify the measurement entry against /proc/cmdline.  How
can the key measurement entry be verified?  Please include that
information, here, in this patch description.

Also, can the key data, now included in the measurement list, be used
to verify signatures in the ima-sig or ima-modsig templates?  Is there
a way of correlating a signature with a key?  Perhaps include a
kselftest as an example.

Mimi

> ---
>  include/linux/ima.h | 13 +++++++++++++
>  security/keys/key.c |  7 +++++++
>  2 files changed, 20 insertions(+)
> 
> diff --git a/include/linux/ima.h b/include/linux/ima.h
> index 6d904754d858..0af88b781ab6 100644
> --- a/include/linux/ima.h
> +++ b/include/linux/ima.h
> @@ -25,6 +25,12 @@ extern int ima_post_read_file(struct file *file, void *buf, loff_t size,
>  extern void ima_post_path_mknod(struct dentry *dentry);
>  extern void ima_kexec_cmdline(const void *buf, int size);
>  
> +#ifdef CONFIG_KEYS
> +extern void ima_post_key_create_or_update(struct key *keyring,
> +					  struct key *key,
> +					  unsigned long flags, bool create);
> +#endif
> +
>  #ifdef CONFIG_IMA_KEXEC
>  extern void ima_add_kexec_buffer(struct kimage *image);
>  #endif
> @@ -101,6 +107,13 @@ static inline void ima_add_kexec_buffer(struct kimage *image)
>  {}
>  #endif
>  
> +#ifndef CONFIG_KEYS
> +static inline void ima_post_key_create_or_update(struct key *keyring,
> +						 struct key *key,
> +						 unsigned long flags,
> +						 bool create) {}
> +#endif
> +
>  #ifdef CONFIG_IMA_APPRAISE
>  extern bool is_ima_appraise_enabled(void);
>  extern void ima_inode_post_setattr(struct dentry *dentry);
> diff --git a/security/keys/key.c b/security/keys/key.c
> index 764f4c57913e..a0f1e7b3b8b9 100644
> --- a/security/keys/key.c
> +++ b/security/keys/key.c
> @@ -13,6 +13,7 @@
>  #include <linux/security.h>
>  #include <linux/workqueue.h>
>  #include <linux/random.h>
> +#include <linux/ima.h>
>  #include <linux/err.h>
>  #include "internal.h"
>  
> @@ -936,6 +937,8 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
>  		goto error_link_end;
>  	}
>  
> +	ima_post_key_create_or_update(keyring, key, flags, true);
> +
>  	key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
>  
>  error_link_end:
> @@ -965,6 +968,10 @@ key_ref_t key_create_or_update(key_ref_t keyring_ref,
>  	}
>  
>  	key_ref = __key_update(key_ref, &prep);
> +
> +	if (!IS_ERR(key_ref))
> +		ima_post_key_create_or_update(keyring, key, flags, false);
> +
>  	goto error_free_prep;
>  }
>  EXPORT_SYMBOL(key_create_or_update);


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v7 4/5] IMA: Add support to limit measuring keys
  2019-11-14 14:37   ` Mimi Zohar
@ 2019-11-14 18:18     ` Lakshmi Ramasubramanian
  0 siblings, 0 replies; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14 18:18 UTC (permalink / raw)
  To: Mimi Zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

On 11/14/2019 6:37 AM, Mimi Zohar wrote:
> Keyrings may be created by userspace with any name (e.g. foo, foobar,
> ...).  A keyring name might be a subset of another keyring name.  For
> example, with the policy "keyrings=foobar", keys being loaded on "foo"
> would also be measured.  Using strstr() will not achieve what is
> needed.
> 
> Mimi

Very good catch - I missed that :(

Will fix and send an update.

thanks,
  -lakshmi


^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v7 3/5] KEYS: Call the IMA hook to measure keys
  2019-11-14 14:54   ` Mimi Zohar
@ 2019-11-14 18:24     ` Lakshmi Ramasubramanian
  2019-11-15 13:14       ` Mimi Zohar
  0 siblings, 1 reply; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14 18:24 UTC (permalink / raw)
  To: Mimi Zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

On 11/14/2019 6:54 AM, Mimi Zohar wrote:

> No need to Cc David Howells on the entire patch set.  Just Cc him,
> here, after your tag.
ok

> With this patch, keys are now being measured.  With the boot command
> line, we can verify the measurement entry against /proc/cmdline.  How
> can the key measurement entry be verified?  Please include that
> information, here, in this patch description.

Glad you could verify measurement of keys. Thanks a lot for trying it.

Will add information on testing\validating the feature.

> Also, can the key data, now included in the measurement list, be used
> to verify signatures in the ima-sig or ima-modsig templates?  Is there
> a way of correlating a signature with a key?  Perhaps include a
> kselftest as an example.
> 
> Mimi

I am not familiar with kselftest. Will take a look and see if it'd be 
possible to correlate a signature with a key.

thanks,
  -lakshmi

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v7 2/5] IMA: Define an IMA hook to measure keys
  2019-11-14  3:11 ` [PATCH v7 2/5] IMA: Define an IMA hook " Lakshmi Ramasubramanian
@ 2019-11-14 18:30   ` Lakshmi Ramasubramanian
  0 siblings, 0 replies; 12+ messages in thread
From: Lakshmi Ramasubramanian @ 2019-11-14 18:30 UTC (permalink / raw)
  To: zohar, dhowells, matthewgarrett, sashal, jamorris,
	linux-integrity, linux-security-module, keyrings, linux-kernel

On 11/13/19 7:11 PM, Lakshmi Ramasubramanian wrote:

> The IMA hook is defined in a new file namely ima_asymmetric_keys.c
> which is built only if CONFIG_KEYS is enabled.

I think instead of CONFIG_KEYS I should use 
CONFIG_ASYMMETRIC_PUBLIC_KEY_SUBTYPE for ima_asymmetric_keys.c since 
this config is enabled only when both CONFIG_ASYMMETRIC_KEY_TYPE and 
CONFIG_KEYS are enabled.

Please see below taken from "crypto/asymmetric_keys/Kconfig"

# SPDX-License-Identifier: GPL-2.0
menuconfig ASYMMETRIC_KEY_TYPE
         bool "Asymmetric (public-key cryptographic) key type"
         depends on KEYS
         help
           This option provides support for a key type that holds the 
data for
           the asymmetric keys used for public key cryptographic 
operations such
           as encryption, decryption, signature generation and signature
           verification.

if ASYMMETRIC_KEY_TYPE

config ASYMMETRIC_PUBLIC_KEY_SUBTYPE
         tristate "Asymmetric public-key crypto algorithm subtype"

endif # ASYMMETRIC_KEY_TYPE

thanks,
  -lakshmi

^ permalink raw reply	[flat|nested] 12+ messages in thread

* Re: [PATCH v7 3/5] KEYS: Call the IMA hook to measure keys
  2019-11-14 18:24     ` Lakshmi Ramasubramanian
@ 2019-11-15 13:14       ` Mimi Zohar
  0 siblings, 0 replies; 12+ messages in thread
From: Mimi Zohar @ 2019-11-15 13:14 UTC (permalink / raw)
  To: Lakshmi Ramasubramanian, dhowells, matthewgarrett, sashal,
	jamorris, linux-integrity, linux-security-module, keyrings,
	linux-kernel

On Thu, 2019-11-14 at 10:24 -0800, Lakshmi Ramasubramanian wrote:
> On 11/14/2019 6:54 AM, Mimi Zohar wrote:
> > With this patch, keys are now being measured.  With the boot command
> > line, we can verify the measurement entry against /proc/cmdline.  How
> > can the key measurement entry be verified?  Please include that
> > information, here, in this patch description.
> 
> Glad you could verify measurement of keys. Thanks a lot for trying it.
> 
> Will add information on testing\validating the feature.

Thank you.

> 
> > Also, can the key data, now included in the measurement list, be used
> > to verify signatures in the ima-sig or ima-modsig templates?  Is there
> > a way of correlating a signature with a key?  Perhaps include a
> > kselftest as an example.
> 
> I am not familiar with kselftest. Will take a look and see if it'd be 
> possible to correlate a signature with a key.

I'd like the measurement list to be self contained, allowing a
regression test, for example, to walk the measurement list, verifying
the file signatures stored in the measurement list based on the key
measurement(s).

It isn't so much about Kselftest, but implementing a regression test
(eg. Kselftest, LTP, ima-evm-utils, ...) as a PoC, in order to know
that the key measurement contains everything needed to identify the
key (eg. keyid, certificate serial number, ...) and verify file
signatures.

Mimi


^ permalink raw reply	[flat|nested] 12+ messages in thread

end of thread, back to index

Thread overview: 12+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-11-14  3:11 [PATCH v7 0/5] KEYS: Measure keys when they are created or updated Lakshmi Ramasubramanian
2019-11-14  3:11 ` [PATCH v7 1/5] IMA: Add KEY_CHECK func to measure keys Lakshmi Ramasubramanian
2019-11-14  3:11 ` [PATCH v7 2/5] IMA: Define an IMA hook " Lakshmi Ramasubramanian
2019-11-14 18:30   ` Lakshmi Ramasubramanian
2019-11-14  3:12 ` [PATCH v7 3/5] KEYS: Call the " Lakshmi Ramasubramanian
2019-11-14 14:54   ` Mimi Zohar
2019-11-14 18:24     ` Lakshmi Ramasubramanian
2019-11-15 13:14       ` Mimi Zohar
2019-11-14  3:12 ` [PATCH v7 4/5] IMA: Add support to limit measuring keys Lakshmi Ramasubramanian
2019-11-14 14:37   ` Mimi Zohar
2019-11-14 18:18     ` Lakshmi Ramasubramanian
2019-11-14  3:12 ` [PATCH v7 5/5] IMA: Read keyrings= option from the IMA policy Lakshmi Ramasubramanian

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