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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2017 Google, Inc.4 * Thiebaud Weksteen <tweek@google.com>5 */6 7#define TPM_MEMREMAP(start, size) early_memremap(start, size)8#define TPM_MEMUNMAP(start, size) early_memunmap(start, size)9 10#include <asm/early_ioremap.h>11#include <linux/efi.h>12#include <linux/init.h>13#include <linux/memblock.h>14#include <linux/tpm_eventlog.h>15 16int efi_tpm_final_log_size;17EXPORT_SYMBOL(efi_tpm_final_log_size);18 19static int __init tpm2_calc_event_log_size(void *data, int count, void *size_info)20{21 struct tcg_pcr_event2_head *header;22 int event_size, size = 0;23 24 while (count > 0) {25 header = data + size;26 event_size = __calc_tpm2_event_size(header, size_info, true);27 if (event_size == 0)28 return -1;29 size += event_size;30 count--;31 }32 33 return size;34}35 36/*37 * Reserve the memory associated with the TPM Event Log configuration table.38 */39int __init efi_tpm_eventlog_init(void)40{41 struct linux_efi_tpm_eventlog *log_tbl;42 struct efi_tcg2_final_events_table *final_tbl;43 int tbl_size;44 int ret = 0;45 46 if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) {47 /*48 * We can't calculate the size of the final events without the49 * first entry in the TPM log, so bail here.50 */51 return 0;52 }53 54 log_tbl = early_memremap(efi.tpm_log, sizeof(*log_tbl));55 if (!log_tbl) {56 pr_err("Failed to map TPM Event Log table @ 0x%lx\n",57 efi.tpm_log);58 efi.tpm_log = EFI_INVALID_TABLE_ADDR;59 return -ENOMEM;60 }61 62 tbl_size = sizeof(*log_tbl) + log_tbl->size;63 memblock_reserve(efi.tpm_log, tbl_size);64 65 if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) {66 pr_info("TPM Final Events table not present\n");67 goto out;68 } else if (log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {69 pr_warn(FW_BUG "TPM Final Events table invalid\n");70 goto out;71 }72 73 final_tbl = early_memremap(efi.tpm_final_log, sizeof(*final_tbl));74 75 if (!final_tbl) {76 pr_err("Failed to map TPM Final Event Log table @ 0x%lx\n",77 efi.tpm_final_log);78 efi.tpm_final_log = EFI_INVALID_TABLE_ADDR;79 ret = -ENOMEM;80 goto out;81 }82 83 tbl_size = 0;84 if (final_tbl->nr_events != 0) {85 void *events = (void *)efi.tpm_final_log86 + sizeof(final_tbl->version)87 + sizeof(final_tbl->nr_events);88 89 tbl_size = tpm2_calc_event_log_size(events,90 final_tbl->nr_events,91 log_tbl->log);92 }93 94 if (tbl_size < 0) {95 pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n");96 ret = -EINVAL;97 goto out_calc;98 }99 100 memblock_reserve(efi.tpm_final_log,101 tbl_size + sizeof(*final_tbl));102 efi_tpm_final_log_size = tbl_size;103 104out_calc:105 early_memunmap(final_tbl, sizeof(*final_tbl));106out:107 early_memunmap(log_tbl, sizeof(*log_tbl));108 return ret;109}110 111