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Commit 2959c95d authored by Jan Kiszka's avatar Jan Kiszka Committed by Ingo Molnar
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efi/capsule: Add support for Quark security header 



The firmware for Quark X102x prepends a security header to the capsule
which is needed to support the mandatory secure boot on this processor.
The header can be detected by checking for the "_CSH" signature and -
to avoid any GUID conflict - validating its size field to contain the
expected value. Then we need to look for the EFI header right after the
security header and pass the real header to __efi_capsule_setup_info.

To be minimal invasive and maximal safe, the quirk version of
efi_capsule_setup_info() is only effective on Quark processors.

Tested-by: default avatarBryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: default avatarJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: default avatarAndy Shevchenko <andy.shevchenko@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170602135207.21708-11-ard.biesheuvel@linaro.org


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 2a457fb3

arch/x86/platform/efi/quirks.c

+137 −0
Original line number Diff line number Diff line
@@ -15,12 +15,66 @@ 
#include <asm/e820/api.h>

#include <asm/efi.h>

#include <asm/uv/uv.h>

#include <asm/cpu_device_id.h>



#define EFI_MIN_RESERVE 5120



#define EFI_DUMMY_GUID \

	EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9)



#define QUARK_CSH_SIGNATURE		0x5f435348	/* _CSH */

#define QUARK_SECURITY_HEADER_SIZE	0x400



/*

 * Header prepended to the standard EFI capsule on Quark systems the are based

 * on Intel firmware BSP.

 * @csh_signature:	Unique identifier to sanity check signed module

 * 			presence ("_CSH").

 * @version:		Current version of CSH used. Should be one for Quark A0.

 * @modulesize:		Size of the entire module including the module header

 * 			and payload.

 * @security_version_number_index: Index of SVN to use for validation of signed

 * 			module.

 * @security_version_number: Used to prevent against roll back of modules.

 * @rsvd_module_id:	Currently unused for Clanton (Quark).

 * @rsvd_module_vendor:	Vendor Identifier. For Intel products value is

 * 			0x00008086.

 * @rsvd_date:		BCD representation of build date as yyyymmdd, where

 * 			yyyy=4 digit year, mm=1-12, dd=1-31.

 * @headersize:		Total length of the header including including any

 * 			padding optionally added by the signing tool.

 * @hash_algo:		What Hash is used in the module signing.

 * @cryp_algo:		What Crypto is used in the module signing.

 * @keysize:		Total length of the key data including including any

 * 			padding optionally added by the signing tool.

 * @signaturesize:	Total length of the signature including including any

 * 			padding optionally added by the signing tool.

 * @rsvd_next_header:	32-bit pointer to the next Secure Boot Module in the

 * 			chain, if there is a next header.

 * @rsvd:		Reserved, padding structure to required size.

 *

 * See also QuartSecurityHeader_t in

 * Quark_EDKII_v1.2.1.1/QuarkPlatformPkg/Include/QuarkBootRom.h

 * from https://downloadcenter.intel.com/download/23197/Intel-Quark-SoC-X1000-Board-Support-Package-BSP

 */

struct quark_security_header {

	u32 csh_signature;

	u32 version;

	u32 modulesize;

	u32 security_version_number_index;

	u32 security_version_number;

	u32 rsvd_module_id;

	u32 rsvd_module_vendor;

	u32 rsvd_date;

	u32 headersize;

	u32 hash_algo;

	u32 cryp_algo;

	u32 keysize;

	u32 signaturesize;

	u32 rsvd_next_header;

	u32 rsvd[2];

};



static efi_char16_t efi_dummy_name[6] = { 'D', 'U', 'M', 'M', 'Y', 0 };



static bool efi_no_storage_paranoia;
@@ -504,3 +558,86 @@ bool efi_poweroff_required(void) 
{

	return acpi_gbl_reduced_hardware || acpi_no_s5;

}



#ifdef CONFIG_EFI_CAPSULE_QUIRK_QUARK_CSH



static int qrk_capsule_setup_info(struct capsule_info *cap_info, void **pkbuff,

				  size_t hdr_bytes)

{

	struct quark_security_header *csh = *pkbuff;



	/* Only process data block that is larger than the security header */

	if (hdr_bytes < sizeof(struct quark_security_header))

		return 0;



	if (csh->csh_signature != QUARK_CSH_SIGNATURE ||

	    csh->headersize != QUARK_SECURITY_HEADER_SIZE)

		return 1;



	/* Only process data block if EFI header is included */

	if (hdr_bytes < QUARK_SECURITY_HEADER_SIZE +

			sizeof(efi_capsule_header_t))

		return 0;



	pr_debug("Quark security header detected\n");



	if (csh->rsvd_next_header != 0) {

		pr_err("multiple Quark security headers not supported\n");

		return -EINVAL;

	}



	*pkbuff += csh->headersize;

	cap_info->total_size = csh->headersize;



	/*

	 * Update the first page pointer to skip over the CSH header.

	 */

	cap_info->pages[0] += csh->headersize;



	return 1;

}



#define ICPU(family, model, quirk_handler) \

	{ X86_VENDOR_INTEL, family, model, X86_FEATURE_ANY, \

	  (unsigned long)&quirk_handler }



static const struct x86_cpu_id efi_capsule_quirk_ids[] = {

	ICPU(5, 9, qrk_capsule_setup_info),	/* Intel Quark X1000 */

	{ }

};



int efi_capsule_setup_info(struct capsule_info *cap_info, void *kbuff,

			   size_t hdr_bytes)

{

	int (*quirk_handler)(struct capsule_info *, void **, size_t);

	const struct x86_cpu_id *id;

	int ret;



	if (hdr_bytes < sizeof(efi_capsule_header_t))

		return 0;



	cap_info->total_size = 0;



	id = x86_match_cpu(efi_capsule_quirk_ids);

	if (id) {

		/*

		 * The quirk handler is supposed to return

		 *  - a value > 0 if the setup should continue, after advancing

		 *    kbuff as needed

		 *  - 0 if not enough hdr_bytes are available yet

		 *  - a negative error code otherwise

		 */

		quirk_handler = (typeof(quirk_handler))id->driver_data;

		ret = quirk_handler(cap_info, &kbuff, hdr_bytes);

		if (ret <= 0)

			return ret;

	}



	memcpy(&cap_info->header, kbuff, sizeof(cap_info->header));



	cap_info->total_size += cap_info->header.imagesize;



	return __efi_capsule_setup_info(cap_info);

}



#endif

drivers/firmware/efi/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -112,6 +112,15 @@ config EFI_CAPSULE_LOADER 


	  Most users should say N.



config EFI_CAPSULE_QUIRK_QUARK_CSH

	boolean "Add support for Quark capsules with non-standard headers"

	depends on X86 && !64BIT

	select EFI_CAPSULE_LOADER

	default y

	help

	  Add support for processing Quark X1000 EFI capsules, whose header

	  layout deviates from the layout mandated by the UEFI specification.



config EFI_TEST

	tristate "EFI Runtime Service Tests Support"

	depends on EFI