1// SPDX-License-Identifier: GPL-2.0
2/*
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 u32 event_size, size = 0;
23
24 while (count > 0) {
25 header = data + size;
26 event_size = __calc_tpm2_event_size(event: header, event_header: size_info, do_mapping: 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 unsigned int tbl_size;
44 int final_tbl_size;
45 int ret = 0;
46
47 if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) {
48 /*
49 * We can't calculate the size of the final events without the
50 * first entry in the TPM log, so bail here.
51 */
52 return 0;
53 }
54
55 log_tbl = early_memremap(phys_addr: efi.tpm_log, size: sizeof(*log_tbl));
56 if (!log_tbl) {
57 pr_err("Failed to map TPM Event Log table @ 0x%lx\n",
58 efi.tpm_log);
59 efi.tpm_log = EFI_INVALID_TABLE_ADDR;
60 return -ENOMEM;
61 }
62
63 tbl_size = sizeof(*log_tbl) + log_tbl->size;
64 if (memblock_reserve(base: efi.tpm_log, size: tbl_size)) {
65 pr_err("TPM Event Log memblock reserve fails (0x%lx, 0x%x)\n",
66 efi.tpm_log, tbl_size);
67 ret = -ENOMEM;
68 goto out;
69 }
70
71 if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) {
72 pr_info("TPM Final Events table not present\n");
73 goto out;
74 } else if (log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {
75 pr_warn(FW_BUG "TPM Final Events table invalid\n");
76 goto out;
77 }
78
79 final_tbl = early_memremap(phys_addr: efi.tpm_final_log, size: sizeof(*final_tbl));
80
81 if (!final_tbl) {
82 pr_err("Failed to map TPM Final Event Log table @ 0x%lx\n",
83 efi.tpm_final_log);
84 efi.tpm_final_log = EFI_INVALID_TABLE_ADDR;
85 ret = -ENOMEM;
86 goto out;
87 }
88
89 final_tbl_size = 0;
90 if (final_tbl->nr_events != 0) {
91 void *events = (void *)efi.tpm_final_log
92 + sizeof(final_tbl->version)
93 + sizeof(final_tbl->nr_events);
94
95 final_tbl_size = tpm2_calc_event_log_size(data: events,
96 count: final_tbl->nr_events,
97 size_info: log_tbl->log);
98 }
99
100 if (final_tbl_size < 0) {
101 pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n");
102 ret = -EINVAL;
103 goto out_calc;
104 }
105
106 memblock_reserve(base: efi.tpm_final_log,
107 size: final_tbl_size + sizeof(*final_tbl));
108 efi_tpm_final_log_size = final_tbl_size;
109
110out_calc:
111 early_memunmap(addr: final_tbl, size: sizeof(*final_tbl));
112out:
113 early_memunmap(addr: log_tbl, size: sizeof(*log_tbl));
114 return ret;
115}
116
117