[PATCH 1/2] powerpc/pseries: define driver for Platform KeyStore
Nayna Jain
nayna at linux.ibm.com
Wed Jul 13 10:59:46 AEST 2022
PowerVM provides an isolated Platform Keystore(PKS) storage allocation
for each LPAR with individually managed access controls to store
sensitive information securely. It provides a new set of hypervisor
calls for Linux kernel to access PKS storage.
Define PLPKS driver using H_CALL interface to access PKS storage.
Signed-off-by: Nayna Jain <nayna at linux.ibm.com>
---
arch/powerpc/include/asm/hvcall.h | 9 +
arch/powerpc/include/asm/plpks.h | 90 ++++
arch/powerpc/platforms/pseries/Kconfig | 13 +
arch/powerpc/platforms/pseries/Makefile | 2 +
arch/powerpc/platforms/pseries/plpks/Makefile | 7 +
arch/powerpc/platforms/pseries/plpks/plpks.c | 509 ++++++++++++++++++
6 files changed, 630 insertions(+)
create mode 100644 arch/powerpc/include/asm/plpks.h
create mode 100644 arch/powerpc/platforms/pseries/plpks/Makefile
create mode 100644 arch/powerpc/platforms/pseries/plpks/plpks.c
diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index d92a20a85395..24b661b0717c 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -97,6 +97,7 @@
#define H_OP_MODE -73
#define H_COP_HW -74
#define H_STATE -75
+#define H_IN_USE -77
#define H_UNSUPPORTED_FLAG_START -256
#define H_UNSUPPORTED_FLAG_END -511
#define H_MULTI_THREADS_ACTIVE -9005
@@ -321,6 +322,14 @@
#define H_SCM_UNBIND_ALL 0x3FC
#define H_SCM_HEALTH 0x400
#define H_SCM_PERFORMANCE_STATS 0x418
+#define H_PKS_GET_CONFIG 0x41C
+#define H_PKS_SET_PASSWORD 0x420
+#define H_PKS_GEN_PASSWORD 0x424
+#define H_PKS_WRITE_OBJECT 0x42C
+#define H_PKS_GEN_KEY 0x430
+#define H_PKS_READ_OBJECT 0x434
+#define H_PKS_REMOVE_OBJECT 0x438
+#define H_PKS_CONFIRM_OBJECT_FLUSHED 0x43C
#define H_RPT_INVALIDATE 0x448
#define H_SCM_FLUSH 0x44C
#define H_GET_ENERGY_SCALE_INFO 0x450
diff --git a/arch/powerpc/include/asm/plpks.h b/arch/powerpc/include/asm/plpks.h
new file mode 100644
index 000000000000..cf60e53e1f15
--- /dev/null
+++ b/arch/powerpc/include/asm/plpks.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2022 IBM Corporation
+ * Author: Nayna Jain <nayna at linux.ibm.com>
+ *
+ * Platform keystore for pseries LPAR(PLPKS).
+ */
+
+#ifndef _PSERIES_PLPKS_H
+#define _PSERIES_PLPKS_H
+
+#include <linux/types.h>
+#include <linux/list.h>
+
+#define OSSECBOOTAUDIT 0x40000000
+#define OSSECBOOTENFORCE 0x20000000
+#define WORLDREADABLE 0x08000000
+#define SIGNEDUPDATE 0x01000000
+
+#define PLPKS_VAR_LINUX 0x01
+#define PLPKS_VAR_COMMON 0x04
+
+struct plpks_var {
+ char *component;
+ u8 os;
+ u8 *name;
+ u16 namelen;
+ u32 policy;
+ u16 datalen;
+ u8 *data;
+};
+
+struct plpks_var_name {
+ u16 namelen;
+ u8 *name;
+};
+
+struct plpks_var_name_list {
+ u32 varcount;
+ struct plpks_var_name varlist[];
+};
+
+struct plpks_config {
+ u8 version;
+ u8 flags;
+ u32 rsvd0;
+ u16 maxpwsize;
+ u16 maxobjlabelsize;
+ u16 maxobjsize;
+ u32 totalsize;
+ u32 usedspace;
+ u32 supportedpolicies;
+ u64 rsvd1;
+} __packed;
+
+/**
+ * Successful return from this API implies PKS is available.
+ * This is used to initialize kernel driver and user interfaces.
+ */
+struct plpks_config *plpks_get_config(void);
+
+/**
+ * Writes the specified var and its data to PKS.
+ * Any caller of PKS driver should present a valid component type for
+ * their variable.
+ */
+int plpks_write_var(struct plpks_var var);
+
+/**
+ * Removes the specified var and its data from PKS.
+ */
+int plpks_remove_var(char *component, u8 varos,
+ struct plpks_var_name vname);
+
+/**
+ * Returns the data for the specified os variable.
+ */
+int plpks_read_os_var(struct plpks_var *var);
+
+/**
+ * Returns the data for the specified firmware variable.
+ */
+int plpks_read_fw_var(struct plpks_var *var);
+
+/**
+ * Returns the data for the specified bootloader variable.
+ */
+int plpks_read_bootloader_var(struct plpks_var *var);
+
+#endif
diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig
index f7fd91d153a4..de6efe5d18c2 100644
--- a/arch/powerpc/platforms/pseries/Kconfig
+++ b/arch/powerpc/platforms/pseries/Kconfig
@@ -142,6 +142,19 @@ config IBMEBUS
help
Bus device driver for GX bus based adapters.
+config PSERIES_PLPKS
+ depends on PPC_PSERIES
+ tristate "Support for the Platform Key Storage"
+ help
+ PowerVM provides an isolated Platform Keystore(PKS) storage
+ allocation for each LPAR with individually managed access
+ controls to store sensitive information securely. It can be
+ used to store asymmetric public keys or secrets as required
+ by different usecases. Select this config to enable
+ operating system interface to hypervisor to access this space.
+
+ If unsure, select N.
+
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 7aaff5323544..d6a9209e08c0 100644
--- a/arch/powerpc/platforms/pseries/Makefile
+++ b/arch/powerpc/platforms/pseries/Makefile
@@ -37,3 +37,5 @@ obj-$(CONFIG_ARCH_HAS_CC_PLATFORM) += cc_platform.o
# nothing that operates in real mode is safe for KASAN
KASAN_SANITIZE_ras.o := n
KASAN_SANITIZE_kexec.o := n
+
+obj-$(CONFIG_PSERIES_PLPKS) += plpks/
diff --git a/arch/powerpc/platforms/pseries/plpks/Makefile b/arch/powerpc/platforms/pseries/plpks/Makefile
new file mode 100644
index 000000000000..e651ace920db
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/plpks/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2022 IBM Corporation
+# Author: Nayna Jain <nayna at linux.ibm.com>
+#
+
+obj-$(CONFIG_PSERIES_PLPKS) += plpks.o
diff --git a/arch/powerpc/platforms/pseries/plpks/plpks.c b/arch/powerpc/platforms/pseries/plpks/plpks.c
new file mode 100644
index 000000000000..463ce93f9066
--- /dev/null
+++ b/arch/powerpc/platforms/pseries/plpks/plpks.c
@@ -0,0 +1,509 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER LPAR Platform KeyStore (PLPKS)
+ * Copyright (C) 2022 IBM Corporation
+ * Author: Nayna Jain <nayna at linux.ibm.com>
+ *
+ * Provides access to variables stored in Power LPAR Platform KeyStore(PLPKS).
+ */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <asm/hvcall.h>
+#include <asm/plpks.h>
+#include <asm/unaligned.h>
+#include <asm/machdep.h>
+
+#define MODULE_VERS "1.0"
+#define MODULE_NAME "pseries-plpks"
+
+#define PKS_FW_OWNER 0x1
+#define PKS_BOOTLOADER_OWNER 0x2
+#define PKS_OS_OWNER 0x3
+
+#define MAX_LABEL_ATTR_SIZE 16
+#define MAX_NAME_SIZE 239
+#define MAX_DATA_SIZE 4000
+
+#define PKS_FLUSH_MAX_TIMEOUT 5000 //msec
+#define PKS_FLUSH_SLEEP 10 //msec
+#define PKS_FLUSH_SLEEP_RANGE 400
+
+static bool configset;
+static struct plpks_config *config;
+static u8 *ospassword;
+static u16 ospasswordlength;
+
+struct plpks_auth {
+ u8 version;
+ u8 consumer;
+ __be64 rsvd0;
+ __be32 rsvd1;
+ __be16 passwordlength;
+ u8 password[];
+} __packed __aligned(16);
+
+struct label_attr {
+ u8 prefix[8];
+ u8 version;
+ u8 os;
+ u8 length;
+ u8 reserved[5];
+};
+
+struct label {
+ struct label_attr attr;
+ u8 name[MAX_NAME_SIZE];
+};
+
+static int pseries_status_to_err(int rc)
+{
+ int err;
+
+ switch (rc) {
+ case H_SUCCESS:
+ err = 0;
+ break;
+ case H_FUNCTION:
+ err = -ENXIO;
+ break;
+ case H_P2:
+ case H_P3:
+ case H_P4:
+ case H_P5:
+ case H_P6:
+ err = -EINVAL;
+ break;
+ case H_NOT_FOUND:
+ err = -ENOENT;
+ break;
+ case H_BUSY:
+ err = -EBUSY;
+ break;
+ case H_AUTHORITY:
+ err = -EPERM;
+ break;
+ case H_NO_MEM:
+ err = -ENOMEM;
+ break;
+ case H_RESOURCE:
+ err = -EEXIST;
+ break;
+ case H_TOO_BIG:
+ err = -EFBIG;
+ break;
+ default:
+ err = -EINVAL;
+ }
+
+ return err;
+}
+
+static int plpks_gen_password(void)
+{
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = {0};
+ u8 consumer = PKS_OS_OWNER;
+ int rc;
+
+ ospassword = kzalloc(config->maxpwsize, GFP_KERNEL);
+ if (!ospassword)
+ return -ENOMEM;
+
+ ospasswordlength = config->maxpwsize;
+ rc = plpar_hcall(H_PKS_GEN_PASSWORD,
+ retbuf,
+ consumer,
+ 0,
+ virt_to_phys(ospassword),
+ config->maxpwsize);
+
+ return pseries_status_to_err(rc);
+}
+
+static int construct_auth(u8 consumer, struct plpks_auth **auth)
+{
+ pr_debug("max password size is %u\n", config->maxpwsize);
+
+ if (!auth || consumer > 3)
+ return -EINVAL;
+
+ *auth = kmalloc(struct_size(*auth, password, config->maxpwsize),
+ GFP_KERNEL);
+ if (!*auth)
+ return -ENOMEM;
+
+ (*auth)->version = 1;
+ (*auth)->consumer = consumer;
+ (*auth)->rsvd0 = 0;
+ (*auth)->rsvd1 = 0;
+ if (consumer == PKS_FW_OWNER || consumer == PKS_BOOTLOADER_OWNER) {
+ pr_debug("consumer is bootloader or firmware\n");
+ (*auth)->passwordlength = 0;
+ return 0;
+ }
+
+ (*auth)->passwordlength = (__force __be16)ospasswordlength;
+
+ memcpy((*auth)->password, ospassword,
+ flex_array_size(*auth, password,
+ (__force u16)((*auth)->passwordlength)));
+ (*auth)->passwordlength = cpu_to_be16((__force u16)((*auth)->passwordlength));
+
+ return 0;
+}
+
+/**
+ * Label is combination of label attributes + name.
+ * Label attributes are used internally by kernel and not exposed to the user.
+ */
+static int construct_label(char *component, u8 varos, u8 *name, u16 namelen, u8 **label)
+{
+ int varlen;
+ int len = 0;
+ int llen = 0;
+ int i;
+ int rc = 0;
+ u8 labellength = MAX_LABEL_ATTR_SIZE;
+
+ if (!label)
+ return -EINVAL;
+
+ varlen = namelen + sizeof(struct label_attr);
+ *label = kzalloc(varlen, GFP_KERNEL);
+
+ if (!*label)
+ return -ENOMEM;
+
+ if (component) {
+ len = strlen(component);
+ memcpy(*label, component, len);
+ }
+ llen = len;
+
+ if (component)
+ len = 8 - strlen(component);
+ else
+ len = 8;
+
+ memset(*label + llen, 0, len);
+ llen = llen + len;
+
+ ((*label)[llen]) = 0;
+ llen = llen + 1;
+
+ memcpy(*label + llen, &varos, 1);
+ llen = llen + 1;
+
+ memcpy(*label + llen, &labellength, 1);
+ llen = llen + 1;
+
+ memset(*label + llen, 0, 5);
+ llen = llen + 5;
+
+ memcpy(*label + llen, name, namelen);
+ llen = llen + namelen;
+
+ for (i = 0; i < llen; i++)
+ pr_debug("%c", (*label)[i]);
+
+ rc = llen;
+ return rc;
+}
+
+static int _plpks_get_config(void)
+{
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = {0};
+ int rc;
+ size_t size = sizeof(struct plpks_config);
+
+ config = kzalloc(size, GFP_KERNEL);
+ if (!config)
+ return -ENOMEM;
+
+ rc = plpar_hcall(H_PKS_GET_CONFIG,
+ retbuf,
+ virt_to_phys(config),
+ size);
+
+ if (rc != H_SUCCESS)
+ return pseries_status_to_err(rc);
+
+ config->rsvd0 = be32_to_cpu((__force __be32)config->rsvd0);
+ config->maxpwsize = be16_to_cpu((__force __be16)config->maxpwsize);
+ config->maxobjlabelsize = be16_to_cpu((__force __be16)config->maxobjlabelsize);
+ config->maxobjsize = be16_to_cpu((__force __be16)config->maxobjsize);
+ config->totalsize = be32_to_cpu((__force __be32)config->totalsize);
+ config->usedspace = be32_to_cpu((__force __be32)config->usedspace);
+ config->supportedpolicies = be32_to_cpu((__force __be32)config->supportedpolicies);
+ config->rsvd1 = be64_to_cpu((__force __be64)config->rsvd1);
+
+ configset = true;
+
+ return 0;
+}
+
+static int plpks_confirm_object_flushed(u8 *label, u16 labellen)
+{
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = {0};
+ int rc;
+ u64 timeout = 0;
+ struct plpks_auth *auth;
+ u8 status;
+ int i;
+
+ rc = construct_auth(PKS_OS_OWNER, &auth);
+ if (rc)
+ return rc;
+
+ for (i = 0; i < labellen; i++)
+ pr_debug("%02x ", label[i]);
+
+ do {
+ rc = plpar_hcall(H_PKS_CONFIRM_OBJECT_FLUSHED,
+ retbuf,
+ virt_to_phys(auth),
+ virt_to_phys(label),
+ labellen);
+
+ status = retbuf[0];
+ if (rc) {
+ pr_info("rc is %d, status is %d\n", rc, status);
+ if (rc == H_NOT_FOUND && status == 1)
+ rc = 0;
+ break;
+ }
+
+ pr_debug("rc is %d, status is %d\n", rc, status);
+
+ if (!rc && status == 1)
+ break;
+
+ usleep_range(PKS_FLUSH_SLEEP, PKS_FLUSH_SLEEP + PKS_FLUSH_SLEEP_RANGE);
+ timeout = timeout + PKS_FLUSH_SLEEP;
+ pr_debug("timeout is %llu\n", timeout);
+
+ } while (timeout < PKS_FLUSH_MAX_TIMEOUT);
+
+ rc = pseries_status_to_err(rc);
+
+ kfree(auth);
+
+ return rc;
+}
+
+int plpks_write_var(struct plpks_var var)
+{
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = {0};
+ int rc;
+ u8 *label;
+ u16 varlen;
+ u8 *data = var.data;
+ struct plpks_auth *auth;
+
+ if (!var.component || !data || var.datalen <= 0 ||
+ var.namelen > MAX_NAME_SIZE ||
+ var.datalen > MAX_DATA_SIZE)
+ return -EINVAL;
+
+ if (var.policy & SIGNEDUPDATE)
+ return -EINVAL;
+
+ rc = construct_auth(PKS_OS_OWNER, &auth);
+ if (rc)
+ return rc;
+
+ rc = construct_label(var.component, var.os, var.name, var.namelen,
+ &label);
+ if (rc <= 0)
+ goto out;
+
+ varlen = rc;
+ pr_debug("Name to be written is of label size %d\n", varlen);
+ rc = plpar_hcall(H_PKS_WRITE_OBJECT,
+ retbuf,
+ virt_to_phys(auth),
+ virt_to_phys(label),
+ varlen,
+ var.policy,
+ virt_to_phys(data),
+ var.datalen);
+
+ if (!rc)
+ rc = plpks_confirm_object_flushed(label, varlen);
+
+ rc = pseries_status_to_err(rc);
+ kfree(label);
+
+out:
+ kfree(auth);
+
+ return rc;
+}
+EXPORT_SYMBOL(plpks_write_var);
+
+int plpks_remove_var(char *component, u8 varos, struct plpks_var_name vname)
+{
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = {0};
+ int rc;
+ u8 *label;
+ u16 varlen;
+ struct plpks_auth *auth;
+
+ if (!component || vname.namelen > MAX_NAME_SIZE)
+ return -EINVAL;
+
+ rc = construct_auth(PKS_OS_OWNER, &auth);
+ if (rc)
+ return rc;
+
+ rc = construct_label(component, varos, vname.name, vname.namelen, &label);
+ if (rc <= 0)
+ goto out;
+
+ varlen = rc;
+ pr_debug("Name to be written is of label size %d\n", varlen);
+ rc = plpar_hcall(H_PKS_REMOVE_OBJECT,
+ retbuf,
+ virt_to_phys(auth),
+ virt_to_phys(label),
+ varlen);
+
+ if (!rc)
+ rc = plpks_confirm_object_flushed(label, varlen);
+
+ rc = pseries_status_to_err(rc);
+ kfree(label);
+
+out:
+ kfree(auth);
+
+ return rc;
+}
+EXPORT_SYMBOL(plpks_remove_var);
+
+static int plpks_read_var(u8 consumer, struct plpks_var *var)
+{
+ unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = {0};
+ int rc;
+ u16 outlen = config->maxobjsize;
+ u8 *label;
+ u8 *out;
+ u16 varlen;
+ struct plpks_auth *auth;
+
+ if (var->namelen > MAX_NAME_SIZE)
+ return -EINVAL;
+
+ rc = construct_auth(PKS_OS_OWNER, &auth);
+ if (rc)
+ return rc;
+
+ rc = construct_label(var->component, var->os, var->name, var->namelen,
+ &label);
+ if (rc <= 0)
+ goto out;
+
+ varlen = rc;
+ pr_debug("Name to be written is of label size %d\n", varlen);
+ out = kzalloc(outlen, GFP_KERNEL);
+ if (!out)
+ goto out1;
+
+ rc = plpar_hcall(H_PKS_READ_OBJECT,
+ retbuf,
+ virt_to_phys(auth),
+ virt_to_phys(label),
+ varlen,
+ virt_to_phys(out),
+ outlen);
+
+ if (rc != H_SUCCESS) {
+ pr_err("Failed to read %d\n", rc);
+ rc = pseries_status_to_err(rc);
+ goto out2;
+ }
+
+ if (var->datalen == 0 || var->datalen > retbuf[0])
+ var->datalen = retbuf[0];
+
+ var->data = kzalloc(var->datalen, GFP_KERNEL);
+ if (!var->data) {
+ rc = -ENOMEM;
+ goto out2;
+ }
+ var->policy = retbuf[1];
+
+ memcpy(var->data, out, var->datalen);
+
+out2:
+ kfree(out);
+
+out1:
+ kfree(label);
+
+out:
+ kfree(auth);
+
+ return rc;
+}
+
+int plpks_read_os_var(struct plpks_var *var)
+{
+ return plpks_read_var(PKS_OS_OWNER, var);
+}
+EXPORT_SYMBOL(plpks_read_os_var);
+
+int plpks_read_fw_var(struct plpks_var *var)
+{
+ return plpks_read_var(PKS_FW_OWNER, var);
+}
+EXPORT_SYMBOL(plpks_read_fw_var);
+
+int plpks_read_bootloader_var(struct plpks_var *var)
+{
+ return plpks_read_var(PKS_BOOTLOADER_OWNER, var);
+}
+EXPORT_SYMBOL(plpks_read_bootloader_var);
+
+struct plpks_config *plpks_get_config(void)
+{
+ if (!configset) {
+ if (_plpks_get_config())
+ return NULL;
+ }
+
+ return config;
+}
+EXPORT_SYMBOL(plpks_get_config);
+
+static __init int pseries_plpks_init(void)
+{
+ int rc = 0;
+
+ rc = _plpks_get_config();
+
+ if (rc) {
+ pr_err("Error initializing plpks\n");
+ return rc;
+ }
+
+ rc = plpks_gen_password();
+ if (rc) {
+ if (rc == H_IN_USE) {
+ rc = 0;
+ } else {
+ pr_err("Failed setting password %d\n", rc);
+ rc = pseries_status_to_err(rc);
+ return rc;
+ }
+ }
+
+ pr_info("POWER LPAR Platform Keystore initialized successfully\n");
+
+ return rc;
+}
+arch_initcall(pseries_plpks_init);
--
2.27.0
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