From: Greg Joyce <gjoyce@xxxxxxxxxxxxxxxxxx>
Self Encrypting Drives(SED) make use of POWER LPAR Platform KeyStore
for storing its variables. Thus the block subsystem needs to access
PowerPC specific functions to read/write objects in PLPKS.
Override the default implementations in lib/arch_vars.c file with
PowerPC specific versions.
Signed-off-by: Greg Joyce <gjoyce@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/platforms/pseries/Makefile | 1 +
.../platforms/pseries/plpks_arch_ops.c | 167 ++++++++++++++++++
2 files changed, 168 insertions(+)
create mode 100644 arch/powerpc/platforms/pseries/plpks_arch_ops.c
diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile
index 14e143b946a3..3a545422eae5 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_PPC_SPLPAR) += vphn.o
obj-$(CONFIG_PPC_SVM) += svm.o
obj-$(CONFIG_FA_DUMP) += rtas-fadump.o
obj-$(CONFIG_PSERIES_PLPKS) += plpks.o
+obj-$(CONFIG_PSERIES_PLPKS) += plpks_arch_ops.o
obj-$(CONFIG_SUSPEND) += suspend.o
obj-$(CONFIG_PPC_VAS) += vas.o vas-sysfs.o
diff --git a/arch/powerpc/platforms/pseries/plpks_arch_ops.c b/arch/powerpc/platforms/pseries/plpks_arch_ops.c
new file mode 100644
index 000000000000..fdea3322f696
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/plpks_arch_ops.c
@@ -0,0 +1,167 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Platform arch specific code for SED
+ * Copyright (C) 2022 IBM Corporation
+ *
+ * Define operations for generic kernel subsystems to read/write keys
+ * from POWER LPAR Platform KeyStore(PLPKS).
+ *
+ * List of subsystems/usecase using PLPKS:
+ * - Self Encrypting Drives(SED)
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/ioctl.h>
+#include <uapi/linux/sed-opal.h>
+#include <linux/sed-opal.h>
+#include <linux/arch_vars.h>
+#include "plpks.h"
+
+/*
+ * variable 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];
+};
+
+/*
+ * ext_type values
+ * 00 no extension exists
+ * 01-1F common
+ * 20-3F AIX
+ * 40-5F Linux
+ * 60-7F IBMi
+ */
+
+/*
+ * This extension is optional for version 1 sed_object_data
+ */
+struct sed_object_extension {
+ u8 ext_type;
+ u8 rsvd[3];
+ u8 ext_data[64];
+};
+
+#define PKS_SED_OBJECT_DATA_V1 1
+#define PKS_SED_MANGLED_LABEL "/default/pri"
+#define PLPKS_SED_COMPONENT "sed-opal"
+
+#define PLPKS_ARCHVAR_POLICY WORLDREADABLE
+#define PLPKS_ARCHVAR_OS_COMMON 4
+
+/*
+ * Read the variable data from PKS given the label
+ */
+int arch_read_variable(enum arch_variable_type type, char *varname,
+ void *varbuf, u_int *varlen)
+{
+ struct plpks_var var;
+ struct plpks_sed_object_data *data;
+ u_int offset = 0;
+ char *buf = (char *)varbuf;
+ int ret;
+
+ var.name = varname;
+ var.namelen = strlen(varname);
+ var.policy = PLPKS_ARCHVAR_POLICY;
+ var.os = PLPKS_ARCHVAR_OS_COMMON;
+ var.data = NULL;
+ var.datalen = 0;
+
+ switch (type) {
+ case ARCH_VAR_OPAL_KEY:
+ var.component = PLPKS_SED_COMPONENT;
+#ifdef OPAL_AUTH_KEY
+ if (strcmp(OPAL_AUTH_KEY, varname) == 0) {
+ var.name = PKS_SED_MANGLED_LABEL;
+ var.namelen = strlen(varname);
+ }
+#endif
+ offset = offsetof(struct plpks_sed_object_data, key);
+ break;
+ case ARCH_VAR_OTHER:
+ var.component = "";
+ break;
+ }
+
+ ret = plpks_read_os_var(&var);
+ if (ret != 0)
+ return ret;
+
+ if (offset > var.datalen)
+ offset = 0;
+
+ switch (type) {
+ case ARCH_VAR_OPAL_KEY:
+ data = (struct plpks_sed_object_data *)var.data;
+ *varlen = data->key_len;
+ break;
+ case ARCH_VAR_OTHER:
+ *varlen = var.datalen;
+ break;
+ }
+
+ if (var.data) {
+ memcpy(varbuf, var.data + offset, var.datalen - offset);
+ buf[*varlen] = '\0';
+ kfree(var.data);
+ }
+
+ return 0;
+}
+
+/*
+ * Write the variable data to PKS given the label
+ */
+int arch_write_variable(enum arch_variable_type type, char *varname,
+ void *varbuf, u_int varlen)
+{
+ struct plpks_var var;
+ struct plpks_sed_object_data data;
+ struct plpks_var_name vname;
+
+ var.name = varname;
+ var.namelen = strlen(varname);
+ var.policy = PLPKS_ARCHVAR_POLICY;
+ var.os = PLPKS_ARCHVAR_OS_COMMON;
+ var.datalen = varlen;
+ var.data = varbuf;
+
+ switch (type) {
+ case ARCH_VAR_OPAL_KEY:
+ var.component = PLPKS_SED_COMPONENT;
+#ifdef OPAL_AUTH_KEY
+ if (strcmp(OPAL_AUTH_KEY, varname) == 0) {
+ var.name = PKS_SED_MANGLED_LABEL;
+ var.namelen = strlen(varname);
+ }
+#endif
+ var.datalen = sizeof(struct plpks_sed_object_data);
+ var.data = (u8 *)&data;
+
+ /* initialize SED object */
+ data.version = PKS_SED_OBJECT_DATA_V1;
+ data.authority = 0;
+ data.range = 0;
+ data.key_len = varlen;
+ memcpy(data.key, varbuf, varlen);
+ break;
+ case ARCH_VAR_OTHER:
+ var.component = "";
+ break;
+ }
+
+ /* variable update requires delete first */
+ vname.namelen = var.namelen;
+ vname.name = var.name;
+ (void)plpks_remove_var(var.component, var.os, vname);
+
+ return plpks_write_var(var);
+}
--
2.27.0
