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 | |
16 | int efi_tpm_final_log_size; |
17 | EXPORT_SYMBOL(efi_tpm_final_log_size); |
18 | |
19 | static int __init tpm2_calc_event_log_size(void *data, int count, void *size_info) |
20 | { |
21 | struct tcg_pcr_event2_head *; |
22 | int 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 | */ |
39 | int __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 the |
49 | * first entry in the TPM log, so bail here. |
50 | */ |
51 | return 0; |
52 | } |
53 | |
54 | log_tbl = early_memremap(phys_addr: efi.tpm_log, size: 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(base: efi.tpm_log, size: 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(phys_addr: efi.tpm_final_log, size: 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_log |
86 | + sizeof(final_tbl->version) |
87 | + sizeof(final_tbl->nr_events); |
88 | |
89 | tbl_size = tpm2_calc_event_log_size(data: events, |
90 | count: final_tbl->nr_events, |
91 | size_info: 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(base: efi.tpm_final_log, |
101 | size: tbl_size + sizeof(*final_tbl)); |
102 | efi_tpm_final_log_size = tbl_size; |
103 | |
104 | out_calc: |
105 | early_memunmap(addr: final_tbl, size: sizeof(*final_tbl)); |
106 | out: |
107 | early_memunmap(addr: log_tbl, size: sizeof(*log_tbl)); |
108 | return ret; |
109 | } |
110 | |
111 | |