include/linux/tpm_eventlog.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */

 #ifndef __LINUX_TPM_EVENTLOG_H__
 #define __LINUX_TPM_EVENTLOG_H__

 #include <linux/tpm.h>

 #define TCG_EVENT_NAME_LEN_MAX	255
 #define MAX_TEXT_EVENT		1000	/* Max event string length */
 #define ACPI_TCPA_SIG		"TCPA"	/* 0x41504354 /'TCPA' */

 #define EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2 0x1
 #define EFI_TCG2_EVENT_LOG_FORMAT_TCG_2   0x2

 #ifdef CONFIG_PPC64
 #define do_endian_conversion(x) be32_to_cpu(x)
 #else
 #define do_endian_conversion(x) x
 #endif

 enum bios_platform_class {
 	BIOS_CLIENT = 0x00,
 	BIOS_SERVER = 0x01,
 };

 struct tcpa_event {
 	u32 pcr_index;
 	u32 event_type;
 	u8 pcr_value[20];	/* SHA1 */
 	u32 event_size;
 	u8 event_data[];
 };

 enum tcpa_event_types {
 	PREBOOT = 0,
 	POST_CODE,
 	UNUSED,
 	NO_ACTION,
 	SEPARATOR,
 	ACTION,
 	EVENT_TAG,
 	SCRTM_CONTENTS,
 	SCRTM_VERSION,
 	CPU_MICROCODE,
 	PLATFORM_CONFIG_FLAGS,
 	TABLE_OF_DEVICES,
 	COMPACT_HASH,
 	IPL,
 	IPL_PARTITION_DATA,
 	NONHOST_CODE,
 	NONHOST_CONFIG,
 	NONHOST_INFO,
 };

 struct tcpa_pc_event {
 	u32 event_id;
 	u32 event_size;
 	u8 event_data[];
 };

 enum tcpa_pc_event_ids {
 	SMBIOS = 1,
 	BIS_CERT,
 	POST_BIOS_ROM,
 	ESCD,
 	CMOS,
 	NVRAM,
 	OPTION_ROM_EXEC,
 	OPTION_ROM_CONFIG,
 	OPTION_ROM_MICROCODE = 10,
 	S_CRTM_VERSION,
 	S_CRTM_CONTENTS,
 	POST_CONTENTS,
 	HOST_TABLE_OF_DEVICES,
 };

 /* http://www.trustedcomputinggroup.org/tcg-efi-protocol-specification/ */

 struct tcg_efi_specid_event_algs {
 	u16 alg_id;
 	u16 digest_size;
 } __packed;

 #define TCG_SPECID_SIG "Spec ID Event03"

 struct tcg_efi_specid_event_head {
 	u8 signature[16];
 	u32 platform_class;
 	u8 spec_version_minor;
 	u8 spec_version_major;
 	u8 spec_errata;
 	u8 uintnsize;
 	u32 num_algs;
 	struct tcg_efi_specid_event_algs digest_sizes[];
 } __packed;

 struct tcg_pcr_event {
 	u32 pcr_idx;
 	u32 event_type;
 	u8 digest[20];
 	u32 event_size;
 	u8 event[];
 } __packed;

 struct tcg_event_field {
 	u32 event_size;
 	u8 event[];
 } __packed;

 struct tcg_pcr_event2_head {
 	u32 pcr_idx;
 	u32 event_type;
 	u32 count;
 	struct tpm_digest digests[];
 } __packed;

 struct tcg_algorithm_size {
 	u16 algorithm_id;
 	u16 algorithm_size;
 };

 struct tcg_algorithm_info {
 	u8 signature[16];
 	u32 platform_class;
 	u8 spec_version_minor;
 	u8 spec_version_major;
 	u8 spec_errata;
 	u8 uintn_size;
 	u32 number_of_algorithms;
 	struct tcg_algorithm_size digest_sizes[];
 };

 #ifndef TPM_MEMREMAP
 #define TPM_MEMREMAP(start, size) NULL
 #endif

 #ifndef TPM_MEMUNMAP
 #define TPM_MEMUNMAP(start, size) do{} while(0)
 #endif

 /**
  * __calc_tpm2_event_size - calculate the size of a TPM2 event log entry
  * @event:        Pointer to the event whose size should be calculated
  * @event_header: Pointer to the initial event containing the digest lengths
  * @do_mapping:   Whether or not the event needs to be mapped
  *
  * The TPM2 event log format can contain multiple digests corresponding to
  * separate PCR banks, and also contains a variable length of the data that
  * was measured. This requires knowledge of how long each digest type is,
  * and this information is contained within the first event in the log.
  *
  * We calculate the length by examining the number of events, and then looking
  * at each event in turn to determine how much space is used for events in
  * total. Once we've done this we know the offset of the data length field,
  * and can calculate the total size of the event.
  *
  * Return: size of the event on success, 0 on failure
  */

 static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
 					 struct tcg_pcr_event *event_header,
 					 bool do_mapping)
 {
 	struct tcg_efi_specid_event_head *efispecid;
 	struct tcg_event_field *event_field;
 	void *mapping = NULL;
 	int mapping_size;
 	void *marker;
 	void *marker_start;
 	u32 halg_size;
 	size_t size;
 	u16 halg;
 	int i;
 	int j;
 	u32 count, event_type;
 	const u8 zero_digest[sizeof(event_header->digest)] = {0};

 	marker = event;
 	marker_start = marker;
 	marker = marker + sizeof(event->pcr_idx) + sizeof(event->event_type)
 		+ sizeof(event->count);

 	/* Map the event header */
 	if (do_mapping) {
 		mapping_size = marker - marker_start;
 		mapping = TPM_MEMREMAP((unsigned long)marker_start,
 				       mapping_size);
 		if (!mapping) {
 			size = 0;
 			goto out;
 		}
 	} else {
 		mapping = marker_start;
 	}

 	event = (struct tcg_pcr_event2_head *)mapping;
 	/*
 	 * The loop below will unmap these fields if the log is larger than
 	 * one page, so save them here for reference:
 	 */
 	count = READ_ONCE(event->count);
 	event_type = READ_ONCE(event->event_type);

 	/* Verify that it's the log header */
 	if (event_header->pcr_idx != 0 ||
 	    event_header->event_type != NO_ACTION ||
 	    memcmp(event_header->digest, zero_digest, sizeof(zero_digest))) {
 		size = 0;
 		goto out;
 	}

 	efispecid = (struct tcg_efi_specid_event_head *)event_header->event;

 	/*
 	 * Perform validation of the event in order to identify malformed
 	 * events. This function may be asked to parse arbitrary byte sequences
 	 * immediately following a valid event log. The caller expects this
 	 * function to recognize that the byte sequence is not a valid event
 	 * and to return an event size of 0.
 	 */
 	if (memcmp(efispecid->signature, TCG_SPECID_SIG,
 		   sizeof(TCG_SPECID_SIG)) ||
 	    !efispecid->num_algs || count != efispecid->num_algs) {
 		size = 0;
 		goto out;
 	}

 	for (i = 0; i < count; i++) {
 		halg_size = sizeof(event->digests[i].alg_id);

 		/* Map the digest's algorithm identifier */
 		if (do_mapping) {
 			TPM_MEMUNMAP(mapping, mapping_size);
 			mapping_size = halg_size;
 			mapping = TPM_MEMREMAP((unsigned long)marker,
 					     mapping_size);
 			if (!mapping) {
 				size = 0;
 				goto out;
 			}
 		} else {
 			mapping = marker;
 		}

 		memcpy(&halg, mapping, halg_size);
 		marker = marker + halg_size;

 		for (j = 0; j < efispecid->num_algs; j++) {
 			if (halg == efispecid->digest_sizes[j].alg_id) {
 				marker +=
 					efispecid->digest_sizes[j].digest_size;
 				break;
 			}
 		}
 		/* Algorithm without known length. Such event is unparseable. */
 		if (j == efispecid->num_algs) {
 			size = 0;
 			goto out;
 		}
 	}

 	/*
 	 * Map the event size - we don't read from the event itself, so
 	 * we don't need to map it
 	 */
 	if (do_mapping) {
 		TPM_MEMUNMAP(mapping, mapping_size);
 		mapping_size += sizeof(event_field->event_size);
 		mapping = TPM_MEMREMAP((unsigned long)marker,
 				       mapping_size);
 		if (!mapping) {
 			size = 0;
 			goto out;
 		}
 	} else {
 		mapping = marker;
 	}

 	event_field = (struct tcg_event_field *)mapping;

 	marker = marker + sizeof(event_field->event_size)
 		+ event_field->event_size;
 	size = marker - marker_start;

 	if (event_type == 0 && event_field->event_size == 0)
 		size = 0;

 out:
 	if (do_mapping)
 		TPM_MEMUNMAP(mapping, mapping_size);
 	return size;
 }

 #endif
	/* SPDX-License-Identifier: GPL-2.0 */

	#ifndef __LINUX_TPM_EVENTLOG_H__
	#define __LINUX_TPM_EVENTLOG_H__

	#include <linux/tpm.h>

	#define TCG_EVENT_NAME_LEN_MAX 255
	#define MAX_TEXT_EVENT 1000 /* Max event string length */
	#define ACPI_TCPA_SIG "TCPA" /* 0x41504354 /'TCPA' */

	#define EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2 0x1
	#define EFI_TCG2_EVENT_LOG_FORMAT_TCG_2 0x2

	#ifdef CONFIG_PPC64
	#define do_endian_conversion(x) be32_to_cpu(x)
	#else
	#define do_endian_conversion(x) x
	#endif

	enum bios_platform_class {
	BIOS_CLIENT = 0x00,
	BIOS_SERVER = 0x01,
	};

	struct tcpa_event {
	u32 pcr_index;
	u32 event_type;
	u8 pcr_value[20]; /* SHA1 */
	u32 event_size;
	u8 event_data[];
	};

	enum tcpa_event_types {
	PREBOOT = 0,
	POST_CODE,
	UNUSED,
	NO_ACTION,
	SEPARATOR,
	ACTION,
	EVENT_TAG,
	SCRTM_CONTENTS,
	SCRTM_VERSION,
	CPU_MICROCODE,
	PLATFORM_CONFIG_FLAGS,
	TABLE_OF_DEVICES,
	COMPACT_HASH,
	IPL,
	IPL_PARTITION_DATA,
	NONHOST_CODE,
	NONHOST_CONFIG,
	NONHOST_INFO,
	};

	struct tcpa_pc_event {
	u32 event_id;
	u32 event_size;
	u8 event_data[];
	};

	enum tcpa_pc_event_ids {
	SMBIOS = 1,
	BIS_CERT,
	POST_BIOS_ROM,
	ESCD,
	CMOS,
	NVRAM,
	OPTION_ROM_EXEC,
	OPTION_ROM_CONFIG,
	OPTION_ROM_MICROCODE = 10,
	S_CRTM_VERSION,
	S_CRTM_CONTENTS,
	POST_CONTENTS,
	HOST_TABLE_OF_DEVICES,
	};

	/* http://www.trustedcomputinggroup.org/tcg-efi-protocol-specification/ */

	struct tcg_efi_specid_event_algs {
	u16 alg_id;
	u16 digest_size;
	} __packed;

	#define TCG_SPECID_SIG "Spec ID Event03"

	struct tcg_efi_specid_event_head {
	u8 signature[16];
	u32 platform_class;
	u8 spec_version_minor;
	u8 spec_version_major;
	u8 spec_errata;
	u8 uintnsize;
	u32 num_algs;
	struct tcg_efi_specid_event_algs digest_sizes[];
	} __packed;

	struct tcg_pcr_event {
	u32 pcr_idx;
	u32 event_type;
	u8 digest[20];
	u32 event_size;
	u8 event[];
	} __packed;

	struct tcg_event_field {
	u32 event_size;
	u8 event[];
	} __packed;

	struct tcg_pcr_event2_head {
	u32 pcr_idx;
	u32 event_type;
	u32 count;
	struct tpm_digest digests[];
	} __packed;

	struct tcg_algorithm_size {
	u16 algorithm_id;
	u16 algorithm_size;
	};

	struct tcg_algorithm_info {
	u8 signature[16];
	u32 platform_class;
	u8 spec_version_minor;
	u8 spec_version_major;
	u8 spec_errata;
	u8 uintn_size;
	u32 number_of_algorithms;
	struct tcg_algorithm_size digest_sizes[];
	};

	#ifndef TPM_MEMREMAP
	#define TPM_MEMREMAP(start, size) NULL
	#endif

	#ifndef TPM_MEMUNMAP
	#define TPM_MEMUNMAP(start, size) do{} while(0)
	#endif

	/**
	* __calc_tpm2_event_size - calculate the size of a TPM2 event log entry
	* @event: Pointer to the event whose size should be calculated
	* @event_header: Pointer to the initial event containing the digest lengths
	* @do_mapping: Whether or not the event needs to be mapped
	*
	* The TPM2 event log format can contain multiple digests corresponding to
	* separate PCR banks, and also contains a variable length of the data that
	* was measured. This requires knowledge of how long each digest type is,
	* and this information is contained within the first event in the log.
	*
	* We calculate the length by examining the number of events, and then looking
	* at each event in turn to determine how much space is used for events in
	* total. Once we've done this we know the offset of the data length field,
	* and can calculate the total size of the event.
	*
	* Return: size of the event on success, 0 on failure
	*/

	static inline int __calc_tpm2_event_size(struct tcg_pcr_event2_head *event,
	struct tcg_pcr_event *event_header,
	bool do_mapping)
	{
	struct tcg_efi_specid_event_head *efispecid;
	struct tcg_event_field *event_field;
	void *mapping = NULL;
	int mapping_size;
	void *marker;
	void *marker_start;
	u32 halg_size;
	size_t size;
	u16 halg;
	int i;
	int j;
	u32 count, event_type;
	const u8 zero_digest[sizeof(event_header->digest)] = {0};

	marker = event;
	marker_start = marker;
	marker = marker + sizeof(event->pcr_idx) + sizeof(event->event_type)
	+ sizeof(event->count);

	/* Map the event header */
	if (do_mapping) {
	mapping_size = marker - marker_start;
	mapping = TPM_MEMREMAP((unsigned long)marker_start,
	mapping_size);
	if (!mapping) {
	size = 0;
	goto out;
	}
	} else {
	mapping = marker_start;
	}

	event = (struct tcg_pcr_event2_head *)mapping;
	/*
	* The loop below will unmap these fields if the log is larger than
	* one page, so save them here for reference:
	*/
	count = READ_ONCE(event->count);
	event_type = READ_ONCE(event->event_type);

	/* Verify that it's the log header */
	if (event_header->pcr_idx != 0 \|\|
	event_header->event_type != NO_ACTION \|\|
	memcmp(event_header->digest, zero_digest, sizeof(zero_digest))) {
	size = 0;
	goto out;
	}

	efispecid = (struct tcg_efi_specid_event_head *)event_header->event;

	/*
	* Perform validation of the event in order to identify malformed
	* events. This function may be asked to parse arbitrary byte sequences
	* immediately following a valid event log. The caller expects this
	* function to recognize that the byte sequence is not a valid event
	* and to return an event size of 0.
	*/
	if (memcmp(efispecid->signature, TCG_SPECID_SIG,
	sizeof(TCG_SPECID_SIG)) \|\|
	!efispecid->num_algs \|\| count != efispecid->num_algs) {
	size = 0;
	goto out;
	}

	for (i = 0; i < count; i++) {
	halg_size = sizeof(event->digests[i].alg_id);

	/* Map the digest's algorithm identifier */
	if (do_mapping) {
	TPM_MEMUNMAP(mapping, mapping_size);
	mapping_size = halg_size;
	mapping = TPM_MEMREMAP((unsigned long)marker,
	mapping_size);
	if (!mapping) {
	size = 0;
	goto out;
	}
	} else {
	mapping = marker;
	}

	memcpy(&halg, mapping, halg_size);
	marker = marker + halg_size;

	for (j = 0; j < efispecid->num_algs; j++) {
	if (halg == efispecid->digest_sizes[j].alg_id) {
	marker +=
	efispecid->digest_sizes[j].digest_size;
	break;
	}
	}
	/* Algorithm without known length. Such event is unparseable. */
	if (j == efispecid->num_algs) {
	size = 0;
	goto out;
	}
	}

	/*
	* Map the event size - we don't read from the event itself, so
	* we don't need to map it
	*/
	if (do_mapping) {
	TPM_MEMUNMAP(mapping, mapping_size);
	mapping_size += sizeof(event_field->event_size);
	mapping = TPM_MEMREMAP((unsigned long)marker,
	mapping_size);
	if (!mapping) {
	size = 0;
	goto out;
	}
	} else {
	mapping = marker;
	}

	event_field = (struct tcg_event_field *)mapping;

	marker = marker + sizeof(event_field->event_size)
	+ event_field->event_size;
	size = marker - marker_start;

	if (event_type == 0 && event_field->event_size == 0)
	size = 0;

	out:
	if (do_mapping)
	TPM_MEMUNMAP(mapping, mapping_size);
	return size;
	}

	#endif