1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2005, 2012 IBM Corporation
4 *
5 * Authors:
6 * Kent Yoder <key@linux.vnet.ibm.com>
7 * Seiji Munetoh <munetoh@jp.ibm.com>
8 * Stefan Berger <stefanb@us.ibm.com>
9 * Reiner Sailer <sailer@watson.ibm.com>
10 * Kylene Hall <kjhall@us.ibm.com>
11 * Nayna Jain <nayna@linux.vnet.ibm.com>
12 *
13 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
14 *
15 * Access to the event log created by a system's firmware / BIOS
16 */
17
18#include <linux/seq_file.h>
19#include <linux/efi.h>
20#include <linux/fs.h>
21#include <linux/security.h>
22#include <linux/module.h>
23#include <linux/slab.h>
24#include <linux/tpm_eventlog.h>
25
26#include "../tpm.h"
27#include "common.h"
28
29
30static const char* tcpa_event_type_strings[] = {
31 "PREBOOT",
32 "POST CODE",
33 "",
34 "NO ACTION",
35 "SEPARATOR",
36 "ACTION",
37 "EVENT TAG",
38 "S-CRTM Contents",
39 "S-CRTM Version",
40 "CPU Microcode",
41 "Platform Config Flags",
42 "Table of Devices",
43 "Compact Hash",
44 "IPL",
45 "IPL Partition Data",
46 "Non-Host Code",
47 "Non-Host Config",
48 "Non-Host Info"
49};
50
51static const char* tcpa_pc_event_id_strings[] = {
52 "",
53 "SMBIOS",
54 "BIS Certificate",
55 "POST BIOS ",
56 "ESCD ",
57 "CMOS",
58 "NVRAM",
59 "Option ROM",
60 "Option ROM config",
61 "",
62 "Option ROM microcode ",
63 "S-CRTM Version",
64 "S-CRTM Contents ",
65 "POST Contents ",
66 "Table of Devices",
67};
68
69/* returns pointer to start of pos. entry of tcg log */
70static void *tpm1_bios_measurements_start(struct seq_file *m, loff_t *pos)
71{
72 loff_t i = 0;
73 struct tpm_chip *chip = m->private;
74 struct tpm_bios_log *log = &chip->log;
75 void *addr = log->bios_event_log;
76 void *limit = log->bios_event_log_end;
77 struct tcpa_event *event;
78 u32 converted_event_size;
79 u32 converted_event_type;
80
81 /* read over *pos measurements */
82 do {
83 event = addr;
84
85 /* check if current entry is valid */
86 if (addr + sizeof(struct tcpa_event) > limit)
87 return NULL;
88
89 converted_event_size =
90 do_endian_conversion(event->event_size);
91 converted_event_type =
92 do_endian_conversion(event->event_type);
93
94 if (((converted_event_type == 0) && (converted_event_size == 0))
95 || ((addr + sizeof(struct tcpa_event) + converted_event_size)
96 > limit))
97 return NULL;
98
99 if (i++ == *pos)
100 break;
101
102 addr += (sizeof(struct tcpa_event) + converted_event_size);
103 } while (1);
104
105 return addr;
106}
107
108static void *tpm1_bios_measurements_next(struct seq_file *m, void *v,
109 loff_t *pos)
110{
111 struct tcpa_event *event = v;
112 struct tpm_chip *chip = m->private;
113 struct tpm_bios_log *log = &chip->log;
114 void *limit = log->bios_event_log_end;
115 u32 converted_event_size;
116 u32 converted_event_type;
117
118 (*pos)++;
119 converted_event_size = do_endian_conversion(event->event_size);
120
121 v += sizeof(struct tcpa_event) + converted_event_size;
122
123 /* now check if current entry is valid */
124 if ((v + sizeof(struct tcpa_event)) > limit)
125 return NULL;
126
127 event = v;
128
129 converted_event_size = do_endian_conversion(event->event_size);
130 converted_event_type = do_endian_conversion(event->event_type);
131
132 if (((converted_event_type == 0) && (converted_event_size == 0)) ||
133 ((v + sizeof(struct tcpa_event) + converted_event_size) > limit))
134 return NULL;
135
136 return v;
137}
138
139static void tpm1_bios_measurements_stop(struct seq_file *m, void *v)
140{
141}
142
143static int get_event_name(char *dest, struct tcpa_event *event,
144 unsigned char * event_entry)
145{
146 const char *name = "";
147 /* 41 so there is room for 40 data and 1 nul */
148 char data[41] = "";
149 int i, n_len = 0, d_len = 0;
150 struct tcpa_pc_event *pc_event;
151
152 switch (do_endian_conversion(event->event_type)) {
153 case PREBOOT:
154 case POST_CODE:
155 case UNUSED:
156 case NO_ACTION:
157 case SCRTM_CONTENTS:
158 case SCRTM_VERSION:
159 case CPU_MICROCODE:
160 case PLATFORM_CONFIG_FLAGS:
161 case TABLE_OF_DEVICES:
162 case COMPACT_HASH:
163 case IPL:
164 case IPL_PARTITION_DATA:
165 case NONHOST_CODE:
166 case NONHOST_CONFIG:
167 case NONHOST_INFO:
168 name = tcpa_event_type_strings[do_endian_conversion
169 (event->event_type)];
170 n_len = strlen(name);
171 break;
172 case SEPARATOR:
173 case ACTION:
174 if (MAX_TEXT_EVENT >
175 do_endian_conversion(event->event_size)) {
176 name = event_entry;
177 n_len = do_endian_conversion(event->event_size);
178 }
179 break;
180 case EVENT_TAG:
181 pc_event = (struct tcpa_pc_event *)event_entry;
182
183 /* ToDo Row data -> Base64 */
184
185 switch (do_endian_conversion(pc_event->event_id)) {
186 case SMBIOS:
187 case BIS_CERT:
188 case CMOS:
189 case NVRAM:
190 case OPTION_ROM_EXEC:
191 case OPTION_ROM_CONFIG:
192 case S_CRTM_VERSION:
193 name = tcpa_pc_event_id_strings[do_endian_conversion
194 (pc_event->event_id)];
195 n_len = strlen(name);
196 break;
197 /* hash data */
198 case POST_BIOS_ROM:
199 case ESCD:
200 case OPTION_ROM_MICROCODE:
201 case S_CRTM_CONTENTS:
202 case POST_CONTENTS:
203 name = tcpa_pc_event_id_strings[do_endian_conversion
204 (pc_event->event_id)];
205 n_len = strlen(name);
206 for (i = 0; i < 20; i++)
207 d_len += sprintf(buf: &data[2*i], fmt: "%02x",
208 pc_event->event_data[i]);
209 break;
210 default:
211 break;
212 }
213 break;
214 default:
215 break;
216 }
217
218 return snprintf(buf: dest, MAX_TEXT_EVENT, fmt: "[%.*s%.*s]",
219 n_len, name, d_len, data);
220
221}
222
223static int tpm1_binary_bios_measurements_show(struct seq_file *m, void *v)
224{
225 struct tcpa_event *event = v;
226 struct tcpa_event temp_event;
227 char *temp_ptr;
228 int i;
229
230 memcpy(&temp_event, event, sizeof(struct tcpa_event));
231
232 /* convert raw integers for endianness */
233 temp_event.pcr_index = do_endian_conversion(event->pcr_index);
234 temp_event.event_type = do_endian_conversion(event->event_type);
235 temp_event.event_size = do_endian_conversion(event->event_size);
236
237 temp_ptr = (char *) &temp_event;
238
239 for (i = 0; i < (sizeof(struct tcpa_event) - 1) ; i++)
240 seq_putc(m, c: temp_ptr[i]);
241
242 temp_ptr = (char *) v;
243
244 for (i = (sizeof(struct tcpa_event) - 1);
245 i < (sizeof(struct tcpa_event) + temp_event.event_size); i++)
246 seq_putc(m, c: temp_ptr[i]);
247
248 return 0;
249
250}
251
252static int tpm1_ascii_bios_measurements_show(struct seq_file *m, void *v)
253{
254 char *eventname;
255 struct tcpa_event *event = v;
256 unsigned char *event_entry =
257 (unsigned char *)(v + sizeof(struct tcpa_event));
258
259 eventname = kmalloc(MAX_TEXT_EVENT, GFP_KERNEL);
260 if (!eventname) {
261 printk(KERN_ERR "%s: ERROR - No Memory for event name\n ",
262 __func__);
263 return -EFAULT;
264 }
265
266 /* 1st: PCR */
267 seq_printf(m, fmt: "%2d ", do_endian_conversion(event->pcr_index));
268
269 /* 2nd: SHA1 */
270 seq_printf(m, fmt: "%20phN", event->pcr_value);
271
272 /* 3rd: event type identifier */
273 seq_printf(m, fmt: " %02x", do_endian_conversion(event->event_type));
274
275 get_event_name(dest: eventname, event, event_entry);
276
277 /* 4th: eventname <= max + \'0' delimiter */
278 seq_printf(m, fmt: " %s\n", eventname);
279
280 kfree(objp: eventname);
281 return 0;
282}
283
284const struct seq_operations tpm1_ascii_b_measurements_seqops = {
285 .start = tpm1_bios_measurements_start,
286 .next = tpm1_bios_measurements_next,
287 .stop = tpm1_bios_measurements_stop,
288 .show = tpm1_ascii_bios_measurements_show,
289};
290
291const struct seq_operations tpm1_binary_b_measurements_seqops = {
292 .start = tpm1_bios_measurements_start,
293 .next = tpm1_bios_measurements_next,
294 .stop = tpm1_bios_measurements_stop,
295 .show = tpm1_binary_bios_measurements_show,
296};
297

source code of linux/drivers/char/tpm/eventlog/tpm1.c