1/*
2 * Copyright (C) 2004 IBM Corporation
3 * Authors:
4 * Leendert van Doorn <leendert@watson.ibm.com>
5 * Dave Safford <safford@watson.ibm.com>
6 * Reiner Sailer <sailer@watson.ibm.com>
7 * Kylene Hall <kjhall@us.ibm.com>
8 *
9 * Copyright (C) 2013 Obsidian Research Corp
10 * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
11 *
12 * sysfs filesystem inspection interface to the TPM
13 *
14 * This program is free software; you can redistribute it and/or
15 * modify it under the terms of the GNU General Public License as
16 * published by the Free Software Foundation, version 2 of the
17 * License.
18 *
19 */
20#include <linux/device.h>
21#include "tpm.h"
22
23#define READ_PUBEK_RESULT_SIZE 314
24#define TPM_ORD_READPUBEK cpu_to_be32(124)
25static struct tpm_input_header tpm_readpubek_header = {
26	.tag = TPM_TAG_RQU_COMMAND,
27	.length = cpu_to_be32(30),
28	.ordinal = TPM_ORD_READPUBEK
29};
30static ssize_t pubek_show(struct device *dev, struct device_attribute *attr,
31			  char *buf)
32{
33	u8 *data;
34	struct tpm_cmd_t tpm_cmd;
35	ssize_t err;
36	int i, rc;
37	char *str = buf;
38
39	struct tpm_chip *chip = dev_get_drvdata(dev);
40
41	tpm_cmd.header.in = tpm_readpubek_header;
42	err = tpm_transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
43			       "attempting to read the PUBEK");
44	if (err)
45		goto out;
46
47	/*
48	   ignore header 10 bytes
49	   algorithm 32 bits (1 == RSA )
50	   encscheme 16 bits
51	   sigscheme 16 bits
52	   parameters (RSA 12->bytes: keybit, #primes, expbit)
53	   keylenbytes 32 bits
54	   256 byte modulus
55	   ignore checksum 20 bytes
56	 */
57	data = tpm_cmd.params.readpubek_out_buffer;
58	str +=
59	    sprintf(str,
60		    "Algorithm: %02X %02X %02X %02X\n"
61		    "Encscheme: %02X %02X\n"
62		    "Sigscheme: %02X %02X\n"
63		    "Parameters: %02X %02X %02X %02X "
64		    "%02X %02X %02X %02X "
65		    "%02X %02X %02X %02X\n"
66		    "Modulus length: %d\n"
67		    "Modulus:\n",
68		    data[0], data[1], data[2], data[3],
69		    data[4], data[5],
70		    data[6], data[7],
71		    data[12], data[13], data[14], data[15],
72		    data[16], data[17], data[18], data[19],
73		    data[20], data[21], data[22], data[23],
74		    be32_to_cpu(*((__be32 *) (data + 24))));
75
76	for (i = 0; i < 256; i++) {
77		str += sprintf(str, "%02X ", data[i + 28]);
78		if ((i + 1) % 16 == 0)
79			str += sprintf(str, "\n");
80	}
81out:
82	rc = str - buf;
83	return rc;
84}
85static DEVICE_ATTR_RO(pubek);
86
87static ssize_t pcrs_show(struct device *dev, struct device_attribute *attr,
88			 char *buf)
89{
90	cap_t cap;
91	u8 digest[TPM_DIGEST_SIZE];
92	ssize_t rc;
93	int i, j, num_pcrs;
94	char *str = buf;
95	struct tpm_chip *chip = dev_get_drvdata(dev);
96
97	rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
98			"attempting to determine the number of PCRS");
99	if (rc)
100		return 0;
101
102	num_pcrs = be32_to_cpu(cap.num_pcrs);
103	for (i = 0; i < num_pcrs; i++) {
104		rc = tpm_pcr_read_dev(chip, i, digest);
105		if (rc)
106			break;
107		str += sprintf(str, "PCR-%02d: ", i);
108		for (j = 0; j < TPM_DIGEST_SIZE; j++)
109			str += sprintf(str, "%02X ", digest[j]);
110		str += sprintf(str, "\n");
111	}
112	return str - buf;
113}
114static DEVICE_ATTR_RO(pcrs);
115
116static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,
117		     char *buf)
118{
119	cap_t cap;
120	ssize_t rc;
121
122	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
123			 "attempting to determine the permanent enabled state");
124	if (rc)
125		return 0;
126
127	rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
128	return rc;
129}
130static DEVICE_ATTR_RO(enabled);
131
132static ssize_t active_show(struct device *dev, struct device_attribute *attr,
133		    char *buf)
134{
135	cap_t cap;
136	ssize_t rc;
137
138	rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
139			 "attempting to determine the permanent active state");
140	if (rc)
141		return 0;
142
143	rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
144	return rc;
145}
146static DEVICE_ATTR_RO(active);
147
148static ssize_t owned_show(struct device *dev, struct device_attribute *attr,
149			  char *buf)
150{
151	cap_t cap;
152	ssize_t rc;
153
154	rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
155			 "attempting to determine the owner state");
156	if (rc)
157		return 0;
158
159	rc = sprintf(buf, "%d\n", cap.owned);
160	return rc;
161}
162static DEVICE_ATTR_RO(owned);
163
164static ssize_t temp_deactivated_show(struct device *dev,
165				     struct device_attribute *attr, char *buf)
166{
167	cap_t cap;
168	ssize_t rc;
169
170	rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
171			 "attempting to determine the temporary state");
172	if (rc)
173		return 0;
174
175	rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
176	return rc;
177}
178static DEVICE_ATTR_RO(temp_deactivated);
179
180static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
181			 char *buf)
182{
183	cap_t cap;
184	ssize_t rc;
185	char *str = buf;
186
187	rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
188			"attempting to determine the manufacturer");
189	if (rc)
190		return 0;
191	str += sprintf(str, "Manufacturer: 0x%x\n",
192		       be32_to_cpu(cap.manufacturer_id));
193
194	/* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
195	rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
196			 "attempting to determine the 1.2 version");
197	if (!rc) {
198		str += sprintf(str,
199			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
200			       cap.tpm_version_1_2.Major,
201			       cap.tpm_version_1_2.Minor,
202			       cap.tpm_version_1_2.revMajor,
203			       cap.tpm_version_1_2.revMinor);
204	} else {
205		/* Otherwise just use TPM_STRUCT_VER */
206		rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
207				"attempting to determine the 1.1 version");
208		if (rc)
209			return 0;
210		str += sprintf(str,
211			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
212			       cap.tpm_version.Major,
213			       cap.tpm_version.Minor,
214			       cap.tpm_version.revMajor,
215			       cap.tpm_version.revMinor);
216	}
217
218	return str - buf;
219}
220static DEVICE_ATTR_RO(caps);
221
222static ssize_t cancel_store(struct device *dev, struct device_attribute *attr,
223			    const char *buf, size_t count)
224{
225	struct tpm_chip *chip = dev_get_drvdata(dev);
226	if (chip == NULL)
227		return 0;
228
229	chip->ops->cancel(chip);
230	return count;
231}
232static DEVICE_ATTR_WO(cancel);
233
234static ssize_t durations_show(struct device *dev, struct device_attribute *attr,
235			      char *buf)
236{
237	struct tpm_chip *chip = dev_get_drvdata(dev);
238
239	if (chip->vendor.duration[TPM_LONG] == 0)
240		return 0;
241
242	return sprintf(buf, "%d %d %d [%s]\n",
243		       jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
244		       jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
245		       jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
246		       chip->vendor.duration_adjusted
247		       ? "adjusted" : "original");
248}
249static DEVICE_ATTR_RO(durations);
250
251static ssize_t timeouts_show(struct device *dev, struct device_attribute *attr,
252			     char *buf)
253{
254	struct tpm_chip *chip = dev_get_drvdata(dev);
255
256	return sprintf(buf, "%d %d %d %d [%s]\n",
257		       jiffies_to_usecs(chip->vendor.timeout_a),
258		       jiffies_to_usecs(chip->vendor.timeout_b),
259		       jiffies_to_usecs(chip->vendor.timeout_c),
260		       jiffies_to_usecs(chip->vendor.timeout_d),
261		       chip->vendor.timeout_adjusted
262		       ? "adjusted" : "original");
263}
264static DEVICE_ATTR_RO(timeouts);
265
266static struct attribute *tpm_dev_attrs[] = {
267	&dev_attr_pubek.attr,
268	&dev_attr_pcrs.attr,
269	&dev_attr_enabled.attr,
270	&dev_attr_active.attr,
271	&dev_attr_owned.attr,
272	&dev_attr_temp_deactivated.attr,
273	&dev_attr_caps.attr,
274	&dev_attr_cancel.attr,
275	&dev_attr_durations.attr,
276	&dev_attr_timeouts.attr,
277	NULL,
278};
279
280static const struct attribute_group tpm_dev_group = {
281	.attrs = tpm_dev_attrs,
282};
283
284int tpm_sysfs_add_device(struct tpm_chip *chip)
285{
286	int err;
287	err = sysfs_create_group(&chip->pdev->kobj,
288				 &tpm_dev_group);
289
290	if (err)
291		dev_err(chip->pdev,
292			"failed to create sysfs attributes, %d\n", err);
293	return err;
294}
295
296void tpm_sysfs_del_device(struct tpm_chip *chip)
297{
298	sysfs_remove_group(&chip->pdev->kobj, &tpm_dev_group);
299}
300