[PATCH v6 0/4] generic and PowerPC SED Opal keystore

[PATCH v6 0/4] generic and PowerPC SED Opal keystore

[gjoyce]

From: Greg Joyce <gjoyce@linux.vnet.ibm.com>

This patchset has gone through numerous rounds of review and
all comments/suggetions have been addressed. I believe that
this patchset is ready for inclusion.

TCG SED Opal is a specification from The Trusted Computing Group
that allows self encrypting storage devices (SED) to be locked at
power on and require an authentication key to unlock the drive.

Generic functions have been defined for accessing SED Opal keys.
The generic functions are defined as weak so that they may be superseded
by keystore specific versions.

PowerPC/pseries versions of these functions provide read/write access
to SED Opal keys in the PLPKS keystore.

The SED block driver has been modified to read the SED Opal
keystore to populate a key in the SED Opal keyring. Changes to the
SED Opal key will be written to the SED Opal keystore.

Patch 3 "keystore access for SED Opal keys" is dependent on:
        https://lore.kernel.org/keyrings/20220818143045.680972-4-gjoyce@linux.vnet.ibm.com/T/#u

Changelog
v6:	- squashed two commits (suggested by Andrew Donnellan)

v5:	- updated to reflect changes in PLPKS API

v4:
        - scope reduced to cover just SED Opal keys
        - base SED Opal keystore is now in SED block driver
        - removed use of enum to indicate type
        - refactored common code into common function that read and
          write use
        - removed cast to void
        - added use of SED Opal keystore functions to SED block driver

v3:
        - No code changes, but per reviewer requests, adding additional
          mailing lists(keyring, EFI) for wider review.

v2:
        - Include feedback from Gregory Joyce, Eric Richter and
          Murilo Opsfelder Araujo.
        - Include suggestions from Michael Ellerman.
        - Moved a dependency from generic SED code to this patchset.
          This patchset now builds of its own.



Greg Joyce (3):
  block:sed-opal: SED Opal keystore
  block: sed-opal: keystore access for SED Opal keys
  powerpc/pseries: PLPKS SED Opal keystore support

 arch/powerpc/platforms/pseries/Kconfig        |   6 +
 arch/powerpc/platforms/pseries/Makefile       |   1 +
 .../powerpc/platforms/pseries/plpks_sed_ops.c | 114 ++++++++++++++++++
 block/Kconfig                                 |   1 +
 block/Makefile                                |   2 +-
 block/sed-opal-key.c                          |  24 ++++
 block/sed-opal.c                              |  18 ++-
 include/linux/sed-opal-key.h                  |  15 +++
 8 files changed, 178 insertions(+), 3 deletions(-)
 create mode 100644 arch/powerpc/platforms/pseries/plpks_sed_ops.c
 create mode 100644 block/sed-opal-key.c
 create mode 100644 include/linux/sed-opal-key.h

-- 
gjoyce@linux.vnet.ibm.com

[PATCH v6 1/3] block:sed-opal: SED Opal keystore

[gjoyce]

From: Greg Joyce <gjoyce@linux.vnet.ibm.com>

TCG SED Opal is a specification from The Trusted Computing Group
that allows self encrypting storage devices (SED) to be locked at
power on and require an authentication key to unlock the drive.

Add read and write functions that allow SED Opal authentication keys
to be stored in a permanent keystore.

Signed-off-by: Greg Joyce <gjoyce@linux.vnet.ibm.com>
Reviewed-by: Jonathan Derrick <jonathan.derrick@linux.dev>
---
 block/Makefile               |  2 +-
 block/sed-opal-key.c         | 24 ++++++++++++++++++++++++
 include/linux/sed-opal-key.h | 15 +++++++++++++++
 3 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 block/sed-opal-key.c
 create mode 100644 include/linux/sed-opal-key.h

diff --git a/block/Makefile b/block/Makefile
index 4e01bb71ad6e..464a9f209552 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -35,7 +35,7 @@ obj-$(CONFIG_BLK_DEV_ZONED)	+= blk-zoned.o
 obj-$(CONFIG_BLK_WBT)		+= blk-wbt.o
 obj-$(CONFIG_BLK_DEBUG_FS)	+= blk-mq-debugfs.o
 obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o
-obj-$(CONFIG_BLK_SED_OPAL)	+= sed-opal.o
+obj-$(CONFIG_BLK_SED_OPAL)	+= sed-opal.o sed-opal-key.o
 obj-$(CONFIG_BLK_PM)		+= blk-pm.o
 obj-$(CONFIG_BLK_INLINE_ENCRYPTION)	+= blk-crypto.o blk-crypto-profile.o \
 					   blk-crypto-sysfs.o
diff --git a/block/sed-opal-key.c b/block/sed-opal-key.c
new file mode 100644
index 000000000000..16f380164c44
--- /dev/null
+++ b/block/sed-opal-key.c
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SED key operations.
+ *
+ * Copyright (C) 2022 IBM Corporation
+ *
+ * These are the accessor functions (read/write) for SED Opal
+ * keys. Specific keystores can provide overrides.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/sed-opal-key.h>
+
+int __weak sed_read_key(char *keyname, char *key, u_int *keylen)
+{
+	return -EOPNOTSUPP;
+}
+
+int __weak sed_write_key(char *keyname, char *key, u_int keylen)
+{
+	return -EOPNOTSUPP;
+}
diff --git a/include/linux/sed-opal-key.h b/include/linux/sed-opal-key.h
new file mode 100644
index 000000000000..c9b1447986d8
--- /dev/null
+++ b/include/linux/sed-opal-key.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * SED key operations.
+ *
+ * Copyright (C) 2022 IBM Corporation
+ *
+ * These are the accessor functions (read/write) for SED Opal
+ * keys. Specific keystores can provide overrides.
+ *
+ */
+
+#include <linux/kernel.h>
+
+int sed_read_key(char *keyname, char *key, u_int *keylen);
+int sed_write_key(char *keyname, char *key, u_int keylen);
-- 
gjoyce@linux.vnet.ibm.com

[PATCH v6 2/3] block/sed-opal: keystore access for SED Opal keys

[gjoyce]

From: Greg Joyce <gjoyce@linux.vnet.ibm.com>

Allow for permanent SED Opal authentication keys by
reading/writing to the SED Opal non-volatile keystore.

Signed-off-by: Greg Joyce <gjoyce@linux.vnet.ibm.com>
Reviewed-by: Jonathan Derrick <jonathan.derrick@linux.dev>
---
 block/sed-opal.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/block/sed-opal.c b/block/sed-opal.c
index 7f5f235a9048..1e8cfa00b609 100644
--- a/block/sed-opal.c
+++ b/block/sed-opal.c
@@ -18,6 +18,7 @@
 #include <linux/uaccess.h>
 #include <uapi/linux/sed-opal.h>
 #include <linux/sed-opal.h>
+#include <linux/sed-opal-key.h>
 #include <linux/string.h>
 #include <linux/kdev_t.h>
 #include <linux/key.h>
@@ -2803,7 +2804,13 @@ static int opal_set_new_pw(struct opal_dev *dev, struct opal_new_pw *opal_pw)
 	if (ret)
 		return ret;
 
-	/* update keyring with new password */
+	/* update keyring and key store with new password */
+	ret = sed_write_key(OPAL_AUTH_KEY,
+			    opal_pw->new_user_pw.opal_key.key,
+			    opal_pw->new_user_pw.opal_key.key_len);
+	if (ret != -EOPNOTSUPP)
+		pr_warn("error updating SED key: %d\n", ret);
+
 	ret = update_sed_opal_key(OPAL_AUTH_KEY,
 				  opal_pw->new_user_pw.opal_key.key,
 				  opal_pw->new_user_pw.opal_key.key_len);
@@ -3050,6 +3057,8 @@ EXPORT_SYMBOL_GPL(sed_ioctl);
 static int __init sed_opal_init(void)
 {
 	struct key *kr;
+	char init_sed_key[OPAL_KEY_MAX];
+	int keylen = OPAL_KEY_MAX - 1;
 
 	kr = keyring_alloc(".sed_opal",
 			   GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(),
@@ -3062,6 +3071,11 @@ static int __init sed_opal_init(void)
 
 	sed_opal_keyring = kr;
 
-	return 0;
+	if (sed_read_key(OPAL_AUTH_KEY, init_sed_key, &keylen) < 0) {
+		memset(init_sed_key, '\0', sizeof(init_sed_key));
+		keylen = OPAL_KEY_MAX - 1;
+	}
+
+	return update_sed_opal_key(OPAL_AUTH_KEY, init_sed_key, keylen);
 }
 late_initcall(sed_opal_init);
-- 
gjoyce@linux.vnet.ibm.com

[PATCH v6 3/3] powerpc/pseries: PLPKS SED Opal keystore support

[gjoyce]

From: Greg Joyce <gjoyce@linux.vnet.ibm.com>

Define operations for SED Opal to read/write keys
from POWER LPAR Platform KeyStore(PLPKS). This allows
non-volatile storage of SED Opal keys.

Signed-off-by: Greg Joyce <gjoyce@linux.vnet.ibm.com>
Reviewed-by: Jonathan Derrick <jonathan.derrick@linux.dev>

---
 arch/powerpc/platforms/pseries/Kconfig        |   6 +
 arch/powerpc/platforms/pseries/Makefile       |   1 +
 .../powerpc/platforms/pseries/plpks_sed_ops.c | 114 ++++++++++++++++++
 block/Kconfig                                 |   1 +
 4 files changed, 122 insertions(+)
 create mode 100644 arch/powerpc/platforms/pseries/plpks_sed_ops.c

diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index 21b22bf16ce6..c2f8a29e7b9b 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -163,6 +163,12 @@ config PSERIES_PLPKS
 	# This option is selected by in-kernel consumers that require
 	# access to the PKS.
 
+config PSERIES_PLPKS_SED
+	depends on PPC_PSERIES
+	bool
+	# This option is selected by in-kernel consumers that require
+	# access to the SED PKS keystore.
+
 config PAPR_SCM
 	depends on PPC_PSERIES && MEMORY_HOTPLUG && LIBNVDIMM
 	tristate "Support for the PAPR Storage Class Memory interface"
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 53c3b91af2f7..1476c5e4433c 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_PPC_SVM)		+= svm.o
 obj-$(CONFIG_FA_DUMP)		+= rtas-fadump.o
 obj-$(CONFIG_PSERIES_PLPKS)	+= plpks.o
 obj-$(CONFIG_PPC_SECURE_BOOT)	+= plpks-secvar.o
+obj-$(CONFIG_PSERIES_PLPKS_SED)	+= plpks_sed_ops.o
 obj-$(CONFIG_SUSPEND)		+= suspend.o
 obj-$(CONFIG_PPC_VAS)		+= vas.o vas-sysfs.o
 
diff --git a/arch/powerpc/platforms/pseries/plpks_sed_ops.c b/arch/powerpc/platforms/pseries/plpks_sed_ops.c
new file mode 100644
index 000000000000..c1d08075e850
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/plpks_sed_ops.c
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Platform specific code for non-volatile SED key access
+ * Copyright (C) 2022 IBM Corporation
+ *
+ * Define operations for SED Opal to read/write keys
+ * from POWER LPAR Platform KeyStore(PLPKS).
+ *
+ * Self Encrypting Drives(SED) key storage using PLPKS
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/ioctl.h>
+#include <linux/sed-opal-key.h>
+#include <asm/plpks.h>
+
+/*
+ * structure that contains all SED data
+ */
+struct plpks_sed_object_data {
+	u_char version;
+	u_char pad1[7];
+	u_long authority;
+	u_long range;
+	u_int  key_len;
+	u_char key[32];
+};
+
+#define PLPKS_SED_OBJECT_DATA_V0        0
+#define PLPKS_SED_MANGLED_LABEL         "/default/pri"
+#define PLPKS_SED_COMPONENT             "sed-opal"
+#define PLPKS_SED_KEY                   "opal-boot-pin"
+
+/*
+ * authority is admin1 and range is global
+ */
+#define PLPKS_SED_AUTHORITY  0x0000000900010001
+#define PLPKS_SED_RANGE      0x0000080200000001
+
+void plpks_init_var(struct plpks_var *var, char *keyname)
+{
+	var->name = keyname;
+	var->namelen = strlen(keyname);
+	if (strcmp(PLPKS_SED_KEY, keyname) == 0) {
+		var->name = PLPKS_SED_MANGLED_LABEL;
+		var->namelen = strlen(keyname);
+	}
+	var->policy = PLPKS_WORLDREADABLE;
+	var->os = PLPKS_VAR_COMMON;
+	var->data = NULL;
+	var->datalen = 0;
+	var->component = PLPKS_SED_COMPONENT;
+}
+
+/*
+ * Read the SED Opal key from PLPKS given the label
+ */
+int sed_read_key(char *keyname, char *key, u_int *keylen)
+{
+	struct plpks_var var;
+	struct plpks_sed_object_data data;
+	int ret;
+	u_int len;
+
+	plpks_init_var(&var, keyname);
+	var.data = (u8 *)&data;
+	var.datalen = sizeof(data);
+
+	ret = plpks_read_os_var(&var);
+	if (ret != 0)
+		return ret;
+
+	len = min_t(u16, be32_to_cpu(data.key_len), var.datalen);
+	memcpy(key, data.key, len);
+	key[len] = '\0';
+	*keylen = len;
+
+	return 0;
+}
+
+/*
+ * Write the SED Opal key to PLPKS given the label
+ */
+int sed_write_key(char *keyname, char *key, u_int keylen)
+{
+	struct plpks_var var;
+	struct plpks_sed_object_data data;
+	struct plpks_var_name vname;
+
+	plpks_init_var(&var, keyname);
+
+	var.datalen = sizeof(struct plpks_sed_object_data);
+	var.data = (u8 *)&data;
+
+	/* initialize SED object */
+	data.version = PLPKS_SED_OBJECT_DATA_V0;
+	data.authority = cpu_to_be64(PLPKS_SED_AUTHORITY);
+	data.range = cpu_to_be64(PLPKS_SED_RANGE);
+	memset(&data.pad1, '\0', sizeof(data.pad1));
+	data.key_len = cpu_to_be32(keylen);
+	memcpy(data.key, (char *)key, keylen);
+
+	/*
+	 * Key update requires remove first. The return value
+	 * is ignored since it's okay if the key doesn't exist.
+	 */
+	vname.namelen = var.namelen;
+	vname.name = var.name;
+	plpks_remove_var(var.component, var.os, vname);
+
+	return plpks_write_var(var);
+}
diff --git a/block/Kconfig b/block/Kconfig
index 76b23114fdeb..75d4db34df5a 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -182,6 +182,7 @@ config BLK_SED_OPAL
 	bool "Logic for interfacing with Opal enabled SEDs"
 	depends on KEYS
 	select PSERIES_PLPKS if PPC_PSERIES
+	select PSERIES_PLPKS_SED if PPC_PSERIES
 	help
 	Builds Logic for interfacing with Opal enabled controllers.
 	Enabling this option enables users to setup/unlock/lock
-- 
gjoyce@linux.vnet.ibm.com