:: limine / common / lib / tpm.h 2.3 KB raw

#ifndef LIB__TPM_H__

#define LIB__TPM_H__

​

#include <stdint.h>

#include <stddef.h>

#include <stdbool.h>

​

// PCR allocation, following the GRUB convention:

//   PCR 8: kernel command line and other authoritative strings

//   PCR 9: kernel image, initrd, devicetree, and other binary blobs

#define TPM_PCR_BOOT_AUTH       8

#define TPM_PCR_LOADED_IMAGES   9

​

// TCG PC Client Platform Firmware Profile event types

#define TPM_EV_IPL              0x0000000d

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#if defined (UEFI)

​

void tpm_init(void);

​

// True if a TCG2 or CC measurement protocol is available.

bool tpm_present(void);

​

void tpm_measure(uint32_t pcr, uint32_t event_type,

                 const void *data, size_t data_size,

                 const char *desc_prefix, const char *desc_value);

​

// Measure a config-supplied URI string into the given PCR with any trailing

// `#<hash>` suffix stripped, so the digest captures only the policy-stable

// portion (resource, root, path, and any `$` decompression marker). The

// event description shows the same stripped string.

void tpm_measure_path(uint32_t pcr, uint32_t event_type,

                      const char *desc_prefix, const char *path);

​

// Capture the firmware TCG2 event log into bootloader-reclaimable memory

// and expose the raw event stream. `format` receives the TCG event log

// format identifier (1 = TCG 1.2, 2 = TCG 2.0 crypto-agile). Returns false

// if no TPM is present or capture failed.

bool tpm_get_event_log(uint32_t *format, void **address, size_t *size);

​

// Free the captured event log buffer. Subsequent tpm_get_event_log() calls

// return false.

void tpm_release_event_log(void);

​

// Compute the in-memory size of one TCG 2.0 crypto-agile event entry.

// `header` must point to the spec-ID event at the start of the log; it

// carries the per-algorithm digest sizes needed to walk variable-length

// digest lists. Returns 0 on malformed input.

uint32_t tpm_calc_event_size(const void *event, const void *header);

​

// Locate the firmware's final-events table for the active measurement

// protocol (EFI_TCG2_FINAL_EVENTS_TABLE_GUID for TCG2, or

// EFI_CC_FINAL_EVENTS_TABLE_GUID for CC). Both tables share the same

// {Version, NumberOfEvents, Events[]} layout. Returns NULL if no TPM/CC

// interface is active or the table isn't present.

void *tpm_get_final_events_table(void);

​

#endif

​

#endif