summaryrefslogtreecommitdiff
path: root/drivers/char/tpm/tpm-sysfs.c
blob: 01730a27ae076c03307be46f9edd4a838cffb04e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
/*
 * Copyright (C) 2004 IBM Corporation
 * Authors:
 * Leendert van Doorn <leendert@watson.ibm.com>
 * Dave Safford <safford@watson.ibm.com>
 * Reiner Sailer <sailer@watson.ibm.com>
 * Kylene Hall <kjhall@us.ibm.com>
 *
 * Copyright (C) 2013 Obsidian Research Corp
 * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
 *
 * sysfs filesystem inspection interface to the TPM
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
 *
 */
#include <linux/device.h>
#include "tpm.h"

/* XXX for now this helper is duplicated in tpm-interface.c */
static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
			    int len, const char *desc)
{
	int err;

	len = tpm_transmit(chip, (u8 *) cmd, len);
	if (len <  0)
		return len;
	else if (len < TPM_HEADER_SIZE)
		return -EFAULT;

	err = be32_to_cpu(cmd->header.out.return_code);
	if (err != 0 && desc)
		dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);

	return err;
}

#define READ_PUBEK_RESULT_SIZE 314
#define TPM_ORD_READPUBEK cpu_to_be32(124)
static struct tpm_input_header tpm_readpubek_header = {
	.tag = TPM_TAG_RQU_COMMAND,
	.length = cpu_to_be32(30),
	.ordinal = TPM_ORD_READPUBEK
};
static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	u8 *data;
	struct tpm_cmd_t tpm_cmd;
	ssize_t err;
	int i, rc;
	char *str = buf;

	struct tpm_chip *chip = dev_get_drvdata(dev);

	tpm_cmd.header.in = tpm_readpubek_header;
	err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
			   "attempting to read the PUBEK");
	if (err)
		goto out;

	/*
	   ignore header 10 bytes
	   algorithm 32 bits (1 == RSA )
	   encscheme 16 bits
	   sigscheme 16 bits
	   parameters (RSA 12->bytes: keybit, #primes, expbit)
	   keylenbytes 32 bits
	   256 byte modulus
	   ignore checksum 20 bytes
	 */
	data = tpm_cmd.params.readpubek_out_buffer;
	str +=
	    sprintf(str,
		    "Algorithm: %02X %02X %02X %02X\n"
		    "Encscheme: %02X %02X\n"
		    "Sigscheme: %02X %02X\n"
		    "Parameters: %02X %02X %02X %02X "
		    "%02X %02X %02X %02X "
		    "%02X %02X %02X %02X\n"
		    "Modulus length: %d\n"
		    "Modulus:\n",
		    data[0], data[1], data[2], data[3],
		    data[4], data[5],
		    data[6], data[7],
		    data[12], data[13], data[14], data[15],
		    data[16], data[17], data[18], data[19],
		    data[20], data[21], data[22], data[23],
		    be32_to_cpu(*((__be32 *) (data + 24))));

	for (i = 0; i < 256; i++) {
		str += sprintf(str, "%02X ", data[i + 28]);
		if ((i + 1) % 16 == 0)
			str += sprintf(str, "\n");
	}
out:
	rc = str - buf;
	return rc;
}
static DEVICE_ATTR_RO(pubek);

static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
			 char *buf)
{
	cap_t cap;
	u8 digest[TPM_DIGEST_SIZE];
	ssize_t rc;
	int i, j, num_pcrs;
	char *str = buf;
	struct tpm_chip *chip = dev_get_drvdata(dev);

	rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
			"attempting to determine the number of PCRS");
	if (rc)
		return 0;

	num_pcrs = be32_to_cpu(cap.num_pcrs);
	for (i = 0; i < num_pcrs; i++) {
		rc = tpm_pcr_read_dev(chip, i, digest);
		if (rc)
			break;
		str += sprintf(str, "PCR-%02d: ", i);
		for (j = 0; j < TPM_DIGEST_SIZE; j++)
			str += sprintf(str, "%02X ", digest[j]);
		str += sprintf(str, "\n");
	}
	return str - buf;
}
static DEVICE_ATTR_RO(pcrs);

static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
		     char *buf)
{
	cap_t cap;
	ssize_t rc;

	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
			 "attempting to determine the permanent enabled state");
	if (rc)
		return 0;

	rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
	return rc;
}
static DEVICE_ATTR_RO(enabled);

static ssize_t active_show(struct device *dev, struct device_attribute *attr,
		    char *buf)
{
	cap_t cap;
	ssize_t rc;

	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
			 "attempting to determine the permanent active state");
	if (rc)
		return 0;

	rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
	return rc;
}
static DEVICE_ATTR_RO(active);

static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
			  char *buf)
{
	cap_t cap;
	ssize_t rc;

	rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
			 "attempting to determine the owner state");
	if (rc)
		return 0;

	rc = sprintf(buf, "%d\n", cap.owned);
	return rc;
}
static DEVICE_ATTR_RO(owned);

static ssize_t temp_deactivated_show(struct device *dev,
				     struct device_attribute *attr, char *buf)
{
	cap_t cap;
	ssize_t rc;

	rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
			 "attempting to determine the temporary state");
	if (rc)
		return 0;

	rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
	return rc;
}
static DEVICE_ATTR_RO(temp_deactivated);

static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
			 char *buf)
{
	cap_t cap;
	ssize_t rc;
	char *str = buf;

	rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
			"attempting to determine the manufacturer");
	if (rc)
		return 0;
	str += sprintf(str, "Manufacturer: 0x%x\n",
		       be32_to_cpu(cap.manufacturer_id));

	/* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
	rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
			 "attempting to determine the 1.2 version");
	if (!rc) {
		str += sprintf(str,
			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
			       cap.tpm_version_1_2.Major,
			       cap.tpm_version_1_2.Minor,
			       cap.tpm_version_1_2.revMajor,
			       cap.tpm_version_1_2.revMinor);
	} else {
		/* Otherwise just use TPM_STRUCT_VER */
		rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
				"attempting to determine the 1.1 version");
		if (rc)
			return 0;
		str += sprintf(str,
			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
			       cap.tpm_version.Major,
			       cap.tpm_version.Minor,
			       cap.tpm_version.revMajor,
			       cap.tpm_version.revMinor);
	}

	return str - buf;
}
static DEVICE_ATTR_RO(caps);

static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
			    const char *buf, size_t count)
{
	struct tpm_chip *chip = dev_get_drvdata(dev);
	if (chip == NULL)
		return 0;

	chip->ops->cancel(chip);
	return count;
}
static DEVICE_ATTR_WO(cancel);

static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
			      char *buf)
{
	struct tpm_chip *chip = dev_get_drvdata(dev);

	if (chip->vendor.duration[TPM_LONG] == 0)
		return 0;

	return sprintf(buf, "%d %d %d [%s]\n",
		       jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
		       jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
		       jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
		       chip->vendor.duration_adjusted
		       ? "adjusted" : "original");
}
static DEVICE_ATTR_RO(durations);

static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
			     char *buf)
{
	struct tpm_chip *chip = dev_get_drvdata(dev);

	return sprintf(buf, "%d %d %d %d [%s]\n",
		       jiffies_to_usecs(chip->vendor.timeout_a),
		       jiffies_to_usecs(chip->vendor.timeout_b),
		       jiffies_to_usecs(chip->vendor.timeout_c),
		       jiffies_to_usecs(chip->vendor.timeout_d),
		       chip->vendor.timeout_adjusted
		       ? "adjusted" : "original");
}
static DEVICE_ATTR_RO(timeouts);

static struct attribute *tpm_dev_attrs[] = {
	&dev_attr_pubek.attr,
	&dev_attr_pcrs.attr,
	&dev_attr_enabled.attr,
	&dev_attr_active.attr,
	&dev_attr_owned.attr,
	&dev_attr_temp_deactivated.attr,
	&dev_attr_caps.attr,
	&dev_attr_cancel.attr,
	&dev_attr_durations.attr,
	&dev_attr_timeouts.attr,
	NULL,
};

static const struct attribute_group tpm_dev_group = {
	.attrs = tpm_dev_attrs,
};

int tpm_sysfs_add_device(struct tpm_chip *chip)
{
	int err;
	err = sysfs_create_group(&chip->dev->kobj,
				 &tpm_dev_group);

	if (err)
		dev_err(chip->dev,
			"failed to create sysfs attributes, %d\n", err);
	return err;
}

void tpm_sysfs_del_device(struct tpm_chip *chip)
{
	sysfs_remove_group(&chip->dev->kobj, &tpm_dev_group);
}