Commit 2454a7af authored by Nayna Jain's avatar Nayna Jain Committed by Michael Ellerman

powerpc/pseries: define driver for Platform KeyStore

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 POWER LPAR Platform KeyStore(PLPKS) driver using H_CALL interface
to access PKS storage.
Signed-off-by: default avatarNayna Jain <nayna@linux.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220723113048.521744-2-nayna@linux.ibm.com
parent d80f6de9
......@@ -79,6 +79,7 @@
#define H_NOT_ENOUGH_RESOURCES -44
#define H_R_STATE -45
#define H_RESCINDED -46
#define H_P1 -54
#define H_P2 -55
#define H_P3 -56
#define H_P4 -57
......@@ -98,6 +99,8 @@
#define H_OP_MODE -73
#define H_COP_HW -74
#define H_STATE -75
#define H_IN_USE -77
#define H_ABORTED -78
#define H_UNSUPPORTED_FLAG_START -256
#define H_UNSUPPORTED_FLAG_END -511
#define H_MULTI_THREADS_ACTIVE -9005
......@@ -322,6 +325,14 @@
#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
......
......@@ -142,6 +142,19 @@ config IBMEBUS
help
Bus device driver for GX bus based adapters.
config PSERIES_PLPKS
depends on PPC_PSERIES
bool "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"
......
......@@ -28,6 +28,7 @@ obj-$(CONFIG_PAPR_SCM) += papr_scm.o
obj-$(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_SUSPEND) += suspend.o
obj-$(CONFIG_PPC_VAS) += vas.o vas-sysfs.o
......
// SPDX-License-Identifier: GPL-2.0-only
/*
* POWER LPAR Platform KeyStore(PLPKS)
* Copyright (C) 2022 IBM Corporation
* Author: Nayna Jain <nayna@linux.ibm.com>
*
* Provides access to variables stored in Power LPAR Platform KeyStore(PLPKS).
*/
#define pr_fmt(fmt) "plpks: " fmt
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>
#include <asm/hvcall.h>
#include "plpks.h"
#define PKS_FW_OWNER 0x1
#define PKS_BOOTLOADER_OWNER 0x2
#define PKS_OS_OWNER 0x3
#define LABEL_VERSION 0
#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 u8 *ospassword;
static u16 ospasswordlength;
// Retrieved with H_PKS_GET_CONFIG
static u16 maxpwsize;
static u16 maxobjsize;
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];
size_t 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_P1:
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;
case H_STATE:
err = -EIO;
break;
case H_R_STATE:
err = -EIO;
break;
case H_IN_USE:
err = -EEXIST;
break;
case H_ABORTED:
err = -EINTR;
break;
default:
err = -EINVAL;
}
return err;
}
static int plpks_gen_password(void)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
u8 *password, consumer = PKS_OS_OWNER;
int rc;
password = kzalloc(maxpwsize, GFP_KERNEL);
if (!password)
return -ENOMEM;
rc = plpar_hcall(H_PKS_GEN_PASSWORD, retbuf, consumer, 0,
virt_to_phys(password), maxpwsize);
if (!rc) {
ospasswordlength = maxpwsize;
ospassword = kzalloc(maxpwsize, GFP_KERNEL);
if (!ospassword) {
kfree(password);
return -ENOMEM;
}
memcpy(ospassword, password, ospasswordlength);
} else {
if (rc == H_IN_USE) {
pr_warn("Password is already set for POWER LPAR Platform KeyStore\n");
rc = 0;
} else {
goto out;
}
}
out:
kfree(password);
return pseries_status_to_err(rc);
}
static struct plpks_auth *construct_auth(u8 consumer)
{
struct plpks_auth *auth;
if (consumer > PKS_OS_OWNER)
return ERR_PTR(-EINVAL);
auth = kmalloc(struct_size(auth, password, maxpwsize), GFP_KERNEL);
if (!auth)
return ERR_PTR(-ENOMEM);
auth->version = 1;
auth->consumer = consumer;
auth->rsvd0 = 0;
auth->rsvd1 = 0;
if (consumer == PKS_FW_OWNER || consumer == PKS_BOOTLOADER_OWNER) {
auth->passwordlength = 0;
return auth;
}
memcpy(auth->password, ospassword, ospasswordlength);
auth->passwordlength = cpu_to_be16(ospasswordlength);
return auth;
}
/**
* Label is combination of label attributes + name.
* Label attributes are used internally by kernel and not exposed to the user.
*/
static struct label *construct_label(char *component, u8 varos, u8 *name,
u16 namelen)
{
struct label *label;
size_t slen;
if (!name || namelen > MAX_NAME_SIZE)
return ERR_PTR(-EINVAL);
slen = strlen(component);
if (component && slen > sizeof(label->attr.prefix))
return ERR_PTR(-EINVAL);
label = kzalloc(sizeof(*label), GFP_KERNEL);
if (!label)
return ERR_PTR(-ENOMEM);
if (component)
memcpy(&label->attr.prefix, component, slen);
label->attr.version = LABEL_VERSION;
label->attr.os = varos;
label->attr.length = MAX_LABEL_ATTR_SIZE;
memcpy(&label->name, name, namelen);
label->size = sizeof(struct label_attr) + namelen;
return label;
}
static int _plpks_get_config(void)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
struct {
u8 version;
u8 flags;
__be32 rsvd0;
__be16 maxpwsize;
__be16 maxobjlabelsize;
__be16 maxobjsize;
__be32 totalsize;
__be32 usedspace;
__be32 supportedpolicies;
__be64 rsvd1;
} __packed config;
size_t size;
int rc;
size = sizeof(config);
rc = plpar_hcall(H_PKS_GET_CONFIG, retbuf, virt_to_phys(&config), size);
if (rc != H_SUCCESS)
return pseries_status_to_err(rc);
maxpwsize = be16_to_cpu(config.maxpwsize);
maxobjsize = be16_to_cpu(config.maxobjsize);
return 0;
}
static int plpks_confirm_object_flushed(struct label *label,
struct plpks_auth *auth)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
u64 timeout = 0;
u8 status;
int rc;
do {
rc = plpar_hcall(H_PKS_CONFIRM_OBJECT_FLUSHED, retbuf,
virt_to_phys(auth), virt_to_phys(label),
label->size);
status = retbuf[0];
if (rc) {
if (rc == H_NOT_FOUND && status == 1)
rc = 0;
break;
}
if (!rc && status == 1)
break;
usleep_range(PKS_FLUSH_SLEEP,
PKS_FLUSH_SLEEP + PKS_FLUSH_SLEEP_RANGE);
timeout = timeout + PKS_FLUSH_SLEEP;
} while (timeout < PKS_FLUSH_MAX_TIMEOUT);
rc = pseries_status_to_err(rc);
return rc;
}
int plpks_write_var(struct plpks_var var)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
struct plpks_auth *auth;
struct label *label;
int rc;
if (!var.component || !var.data || var.datalen <= 0 ||
var.namelen > MAX_NAME_SIZE || var.datalen > MAX_DATA_SIZE)
return -EINVAL;
if (var.policy & SIGNEDUPDATE)
return -EINVAL;
auth = construct_auth(PKS_OS_OWNER);
if (IS_ERR(auth))
return PTR_ERR(auth);
label = construct_label(var.component, var.os, var.name, var.namelen);
if (IS_ERR(label)) {
rc = PTR_ERR(label);
goto out;
}
rc = plpar_hcall(H_PKS_WRITE_OBJECT, retbuf, virt_to_phys(auth),
virt_to_phys(label), label->size, var.policy,
virt_to_phys(var.data), var.datalen);
if (!rc)
rc = plpks_confirm_object_flushed(label, auth);
if (rc)
pr_err("Failed to write variable %s for component %s with error %d\n",
var.name, var.component, rc);
rc = pseries_status_to_err(rc);
kfree(label);
out:
kfree(auth);
return rc;
}
int plpks_remove_var(char *component, u8 varos, struct plpks_var_name vname)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
struct plpks_auth *auth;
struct label *label;
int rc;
if (!component || vname.namelen > MAX_NAME_SIZE)
return -EINVAL;
auth = construct_auth(PKS_OS_OWNER);
if (IS_ERR(auth))
return PTR_ERR(auth);
label = construct_label(component, varos, vname.name, vname.namelen);
if (IS_ERR(label)) {
rc = PTR_ERR(label);
goto out;
}
rc = plpar_hcall(H_PKS_REMOVE_OBJECT, retbuf, virt_to_phys(auth),
virt_to_phys(label), label->size);
if (!rc)
rc = plpks_confirm_object_flushed(label, auth);
if (rc)
pr_err("Failed to remove variable %s for component %s with error %d\n",
vname.name, component, rc);
rc = pseries_status_to_err(rc);
kfree(label);
out:
kfree(auth);
return rc;
}
static int plpks_read_var(u8 consumer, struct plpks_var *var)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE] = { 0 };
struct plpks_auth *auth;
struct label *label;
u8 *output;
int rc;
if (var->namelen > MAX_NAME_SIZE)
return -EINVAL;
auth = construct_auth(PKS_OS_OWNER);
if (IS_ERR(auth))
return PTR_ERR(auth);
label = construct_label(var->component, var->os, var->name,
var->namelen);
if (IS_ERR(label)) {
rc = PTR_ERR(label);
goto out_free_auth;
}
output = kzalloc(maxobjsize, GFP_KERNEL);
if (!output) {
rc = -ENOMEM;
goto out_free_label;
}
rc = plpar_hcall(H_PKS_READ_OBJECT, retbuf, virt_to_phys(auth),
virt_to_phys(label), label->size, virt_to_phys(output),
maxobjsize);
if (rc != H_SUCCESS) {
pr_err("Failed to read variable %s for component %s with error %d\n",
var->name, var->component, rc);
rc = pseries_status_to_err(rc);
goto out_free_output;
}
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 out_free_output;
}
var->policy = retbuf[1];
memcpy(var->data, output, var->datalen);
rc = 0;
out_free_output:
kfree(output);
out_free_label:
kfree(label);
out_free_auth:
kfree(auth);
return rc;
}
int plpks_read_os_var(struct plpks_var *var)
{
return plpks_read_var(PKS_OS_OWNER, var);
}
int plpks_read_fw_var(struct plpks_var *var)
{
return plpks_read_var(PKS_FW_OWNER, var);
}
int plpks_read_bootloader_var(struct plpks_var *var)
{
return plpks_read_var(PKS_BOOTLOADER_OWNER, var);
}
static __init int pseries_plpks_init(void)
{
int rc;
rc = _plpks_get_config();
if (rc) {
pr_err("POWER LPAR Platform KeyStore is not supported or enabled\n");
return rc;
}
rc = plpks_gen_password();
if (rc)
pr_err("Failed setting POWER LPAR Platform KeyStore Password\n");
else
pr_info("POWER LPAR Platform KeyStore initialized successfully\n");
return rc;
}
arch_initcall(pseries_plpks_init);
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2022 IBM Corporation
* Author: Nayna Jain <nayna@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 *name;
u8 *data;
u32 policy;
u16 namelen;
u16 datalen;
u8 os;
};
struct plpks_var_name {
u8 *name;
u16 namelen;
};
struct plpks_var_name_list {
u32 varcount;
struct plpks_var_name varlist[];
};
/**
* 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
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