[thirdparty/kernel/stable.git] / arch / x86 / xen / efi.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2014 Oracle Co., Daniel Kiper
 */

#include <linux/bitops.h>
#include <linux/efi.h>
#include <linux/init.h>
#include <linux/string.h>

#include <xen/xen.h>
#include <xen/xen-ops.h>
#include <xen/interface/platform.h>

#include <asm/page.h>
#include <asm/setup.h>
#include <asm/xen/hypercall.h>

#include "xen-ops.h"

static efi_char16_t vendor[100] __initdata;

static efi_system_table_t efi_systab_xen __initdata = {
	.hdr = {
		.signature	= EFI_SYSTEM_TABLE_SIGNATURE,
		.revision	= 0, /* Initialized later. */
		.headersize	= 0, /* Ignored by Linux Kernel. */
		.crc32		= 0, /* Ignored by Linux Kernel. */
		.reserved	= 0
	},
	.fw_vendor	= EFI_INVALID_TABLE_ADDR, /* Initialized later. */
	.fw_revision	= 0,			  /* Initialized later. */
	.con_in_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.con_in		= NULL,			  /* Not used under Xen. */
	.con_out_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.con_out	= NULL, 		  /* Not used under Xen. */
	.stderr_handle	= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.stderr		= EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	.runtime	= (efi_runtime_services_t *)EFI_INVALID_TABLE_ADDR,
						  /* Not used under Xen. */
	.boottime	= (efi_boot_services_t *)EFI_INVALID_TABLE_ADDR,
						  /* Not used under Xen. */
	.nr_tables	= 0,			  /* Initialized later. */
	.tables		= EFI_INVALID_TABLE_ADDR  /* Initialized later. */
};

static efi_system_table_t __init *xen_efi_probe(void)
{
	struct xen_platform_op op = {
		.cmd = XENPF_firmware_info,
		.u.firmware_info = {
			.type = XEN_FW_EFI_INFO,
			.index = XEN_FW_EFI_CONFIG_TABLE
		}
	};
	union xenpf_efi_info *info = &op.u.firmware_info.u.efi_info;

	if (!xen_initial_domain() || HYPERVISOR_platform_op(&op) < 0)
		return NULL;

	/* Here we know that Xen runs on EFI platform. */
	xen_efi_runtime_setup();

	efi_systab_xen.tables = info->cfg.addr;
	efi_systab_xen.nr_tables = info->cfg.nent;

	op.cmd = XENPF_firmware_info;
	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	op.u.firmware_info.index = XEN_FW_EFI_VENDOR;
	info->vendor.bufsz = sizeof(vendor);
	set_xen_guest_handle(info->vendor.name, vendor);

	if (HYPERVISOR_platform_op(&op) == 0) {
		efi_systab_xen.fw_vendor = __pa_symbol(vendor);
		efi_systab_xen.fw_revision = info->vendor.revision;
	} else
		efi_systab_xen.fw_vendor = __pa_symbol(L"UNKNOWN");

	op.cmd = XENPF_firmware_info;
	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	op.u.firmware_info.index = XEN_FW_EFI_VERSION;

	if (HYPERVISOR_platform_op(&op) == 0)
		efi_systab_xen.hdr.revision = info->version;

	op.cmd = XENPF_firmware_info;
	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	op.u.firmware_info.index = XEN_FW_EFI_RT_VERSION;

	if (HYPERVISOR_platform_op(&op) == 0)
		efi.runtime_version = info->version;

	return &efi_systab_xen;
}

/*
 * Determine whether we're in secure boot mode.
 */
static enum efi_secureboot_mode xen_efi_get_secureboot(void)
{
	static efi_guid_t shim_guid = EFI_SHIM_LOCK_GUID;
	enum efi_secureboot_mode mode;
	efi_status_t status;
	u8 moksbstate;
	unsigned long size;

	mode = efi_get_secureboot_mode(efi.get_variable);
	if (mode == efi_secureboot_mode_unknown) {
		pr_err("Could not determine UEFI Secure Boot status.\n");
		return efi_secureboot_mode_unknown;
	}
	if (mode != efi_secureboot_mode_enabled)
		return mode;

	/* See if a user has put the shim into insecure mode. */
	size = sizeof(moksbstate);
	status = efi.get_variable(L"MokSBStateRT", &shim_guid,
				  NULL, &size, &moksbstate);

	/* If it fails, we don't care why. Default to secure. */
	if (status != EFI_SUCCESS)
		goto secure_boot_enabled;

	if (moksbstate == 1)
		return efi_secureboot_mode_disabled;

 secure_boot_enabled:
	pr_info("UEFI Secure Boot is enabled.\n");
	return efi_secureboot_mode_enabled;
}

void __init xen_efi_init(struct boot_params *boot_params)
{
	efi_system_table_t *efi_systab_xen;

	efi_systab_xen = xen_efi_probe();

	if (efi_systab_xen == NULL)
		return;

	strscpy((char *)&boot_params->efi_info.efi_loader_signature, "Xen",
			sizeof(boot_params->efi_info.efi_loader_signature));
	boot_params->efi_info.efi_systab = (__u32)__pa(efi_systab_xen);
	boot_params->efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32);

	boot_params->secure_boot = xen_efi_get_secureboot();

	set_bit(EFI_BOOT, &efi.flags);
	set_bit(EFI_PARAVIRT, &efi.flags);
	set_bit(EFI_64BIT, &efi.flags);
}
Commit	Line	Data
901d209a	1	// SPDX-License-Identifier: GPL-2.0
c7341d6a DK	2	/*
c7341d6a DK	3	* Copyright (c) 2014 Oracle Co., Daniel Kiper
c7341d6a DK	4	*/
c7341d6a DK	5
342cd340	6	#include <linux/bitops.h>
c7341d6a DK	7	#include <linux/efi.h>
	8	#include <linux/init.h>
	9	#include <linux/string.h>
	10
a62ed500	11	#include <xen/xen.h>
c7341d6a	12	#include <xen/xen-ops.h>
a62ed500	13	#include <xen/interface/platform.h>
c7341d6a	14
342cd340	15	#include <asm/page.h>
c7341d6a	16	#include <asm/setup.h>
a62ed500 SZ	17	#include <asm/xen/hypercall.h>
a62ed500 SZ	18
fb9b7b4b AB	19	#include "xen-ops.h"
fb9b7b4b AB	20
a62ed500 SZ	21	static efi_char16_t vendor[100] __initdata;
	22
	23	static efi_system_table_t efi_systab_xen __initdata = {
	24	.hdr = {
	25	.signature = EFI_SYSTEM_TABLE_SIGNATURE,
	26	.revision = 0, /* Initialized later. */
	27	.headersize = 0, /* Ignored by Linux Kernel. */
	28	.crc32 = 0, /* Ignored by Linux Kernel. */
	29	.reserved = 0
	30	},
	31	.fw_vendor = EFI_INVALID_TABLE_ADDR, /* Initialized later. */
	32	.fw_revision = 0, /* Initialized later. */
	33	.con_in_handle = EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
9b47c527	34	.con_in = NULL, /* Not used under Xen. */
a62ed500	35	.con_out_handle = EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
960a8d01	36	.con_out = NULL, /* Not used under Xen. */
a62ed500 SZ	37	.stderr_handle = EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	38	.stderr = EFI_INVALID_TABLE_ADDR, /* Not used under Xen. */
	39	.runtime = (efi_runtime_services_t *)EFI_INVALID_TABLE_ADDR,
	40	/* Not used under Xen. */
	41	.boottime = (efi_boot_services_t *)EFI_INVALID_TABLE_ADDR,
	42	/* Not used under Xen. */
	43	.nr_tables = 0, /* Initialized later. */
	44	.tables = EFI_INVALID_TABLE_ADDR /* Initialized later. */
	45	};
	46
a62ed500 SZ	47	static efi_system_table_t __init *xen_efi_probe(void)
	48	{
	49	struct xen_platform_op op = {
	50	.cmd = XENPF_firmware_info,
	51	.u.firmware_info = {
	52	.type = XEN_FW_EFI_INFO,
	53	.index = XEN_FW_EFI_CONFIG_TABLE
	54	}
	55	};
	56	union xenpf_efi_info *info = &op.u.firmware_info.u.efi_info;
	57
	58	if (!xen_initial_domain() \|\| HYPERVISOR_platform_op(&op) < 0)
	59	return NULL;
	60
	61	/* Here we know that Xen runs on EFI platform. */
09515706	62	xen_efi_runtime_setup();
a62ed500 SZ	63
	64	efi_systab_xen.tables = info->cfg.addr;
	65	efi_systab_xen.nr_tables = info->cfg.nent;
	66
	67	op.cmd = XENPF_firmware_info;
	68	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	69	op.u.firmware_info.index = XEN_FW_EFI_VENDOR;
	70	info->vendor.bufsz = sizeof(vendor);
	71	set_xen_guest_handle(info->vendor.name, vendor);
	72
	73	if (HYPERVISOR_platform_op(&op) == 0) {
	74	efi_systab_xen.fw_vendor = __pa_symbol(vendor);
	75	efi_systab_xen.fw_revision = info->vendor.revision;
	76	} else
	77	efi_systab_xen.fw_vendor = __pa_symbol(L"UNKNOWN");
	78
	79	op.cmd = XENPF_firmware_info;
	80	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	81	op.u.firmware_info.index = XEN_FW_EFI_VERSION;
	82
	83	if (HYPERVISOR_platform_op(&op) == 0)
	84	efi_systab_xen.hdr.revision = info->version;
	85
	86	op.cmd = XENPF_firmware_info;
	87	op.u.firmware_info.type = XEN_FW_EFI_INFO;
	88	op.u.firmware_info.index = XEN_FW_EFI_RT_VERSION;
	89
	90	if (HYPERVISOR_platform_op(&op) == 0)
	91	efi.runtime_version = info->version;
	92
	93	return &efi_systab_xen;
	94	}
c7341d6a	95
a7012bdb DK	96	/*
a7012bdb DK	97	* Determine whether we're in secure boot mode.
a7012bdb DK	98	*/
	99	static enum efi_secureboot_mode xen_efi_get_secureboot(void)
	100	{
a7012bdb	101	static efi_guid_t shim_guid = EFI_SHIM_LOCK_GUID;
b283477d	102	enum efi_secureboot_mode mode;
a7012bdb	103	efi_status_t status;
b283477d	104	u8 moksbstate;
a7012bdb DK	105	unsigned long size;
a7012bdb DK	106
b283477d AB	107	mode = efi_get_secureboot_mode(efi.get_variable);
	108	if (mode == efi_secureboot_mode_unknown) {
	109	pr_err("Could not determine UEFI Secure Boot status.\n");
	110	return efi_secureboot_mode_unknown;
	111	}
	112	if (mode != efi_secureboot_mode_enabled)
	113	return mode;
a7012bdb DK	114
	115	/* See if a user has put the shim into insecure mode. */
	116	size = sizeof(moksbstate);
	117	status = efi.get_variable(L"MokSBStateRT", &shim_guid,
	118	NULL, &size, &moksbstate);
	119
	120	/* If it fails, we don't care why. Default to secure. */
	121	if (status != EFI_SUCCESS)
	122	goto secure_boot_enabled;
	123
	124	if (moksbstate == 1)
	125	return efi_secureboot_mode_disabled;
	126
	127	secure_boot_enabled:
	128	pr_info("UEFI Secure Boot is enabled.\n");
	129	return efi_secureboot_mode_enabled;
a7012bdb DK	130	}
a7012bdb DK	131
72813bfb	132	void __init xen_efi_init(struct boot_params *boot_params)
c7341d6a DK	133	{
	134	efi_system_table_t *efi_systab_xen;
	135
	136	efi_systab_xen = xen_efi_probe();
	137
	138	if (efi_systab_xen == NULL)
	139	return;
	140
0fc6ff5a	141	strscpy((char *)&boot_params->efi_info.efi_loader_signature, "Xen",
72813bfb RPM	142	sizeof(boot_params->efi_info.efi_loader_signature));
	143	boot_params->efi_info.efi_systab = (__u32)__pa(efi_systab_xen);
	144	boot_params->efi_info.efi_systab_hi = (__u32)(__pa(efi_systab_xen) >> 32);
c7341d6a	145
72813bfb	146	boot_params->secure_boot = xen_efi_get_secureboot();
a7012bdb	147
c7341d6a DK	148	set_bit(EFI_BOOT, &efi.flags);
	149	set_bit(EFI_PARAVIRT, &efi.flags);
	150	set_bit(EFI_64BIT, &efi.flags);
	151	}