From 2454a7af0f2a42918aa972147a0bec38e6656cd8 Mon Sep 17 00:00:00 2001 From: Nayna Jain Date: Sat, 23 Jul 2022 07:30:46 -0400 Subject: 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: Nayna Jain Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220723113048.521744-2-nayna@linux.ibm.com --- arch/powerpc/platforms/pseries/Kconfig | 13 + arch/powerpc/platforms/pseries/Makefile | 1 + arch/powerpc/platforms/pseries/plpks.c | 460 ++++++++++++++++++++++++++++++++ arch/powerpc/platforms/pseries/plpks.h | 71 +++++ 4 files changed, 545 insertions(+) create mode 100644 arch/powerpc/platforms/pseries/plpks.c create mode 100644 arch/powerpc/platforms/pseries/plpks.h (limited to 'arch/powerpc/platforms') diff --git a/arch/powerpc/platforms/pseries/Kconfig b/arch/powerpc/platforms/pseries/Kconfig index f7fd91d153a4..c4a6d4083a7a 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 + 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" diff --git a/arch/powerpc/platforms/pseries/Makefile b/arch/powerpc/platforms/pseries/Makefile index 7aaff5323544..14e143b946a3 100644 --- a/arch/powerpc/platforms/pseries/Makefile +++ b/arch/powerpc/platforms/pseries/Makefile @@ -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 diff --git a/arch/powerpc/platforms/pseries/plpks.c b/arch/powerpc/platforms/pseries/plpks.c new file mode 100644 index 000000000000..52aaa2894606 --- /dev/null +++ b/arch/powerpc/platforms/pseries/plpks.c @@ -0,0 +1,460 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * POWER LPAR Platform KeyStore(PLPKS) + * Copyright (C) 2022 IBM Corporation + * Author: Nayna Jain + * + * Provides access to variables stored in Power LPAR Platform KeyStore(PLPKS). + */ + +#define pr_fmt(fmt) "plpks: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include + +#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); diff --git a/arch/powerpc/platforms/pseries/plpks.h b/arch/powerpc/platforms/pseries/plpks.h new file mode 100644 index 000000000000..c6a291367bb1 --- /dev/null +++ b/arch/powerpc/platforms/pseries/plpks.h @@ -0,0 +1,71 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022 IBM Corporation + * Author: Nayna Jain + * + * Platform keystore for pseries LPAR(PLPKS). + */ + +#ifndef _PSERIES_PLPKS_H +#define _PSERIES_PLPKS_H + +#include +#include + +#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 -- cgit v1.2.3-59-g8ed1b