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[PATCH] block cleanups: Add kconfig default iosched submenu
[linux-2.6/mini2440.git] / drivers / char / tpm / tpm.c
blob049d128ae7f07de2605cd5cd2e3d4c4efdba26ac
1 /*
2 * Copyright (C) 2004 IBM Corporation
3 *
4 * Authors:
5 * Leendert van Doorn <leendert@watson.ibm.com>
6 * Dave Safford <safford@watson.ibm.com>
7 * Reiner Sailer <sailer@watson.ibm.com>
8 * Kylene Hall <kjhall@us.ibm.com>
9 *
10 * Maintained by: <tpmdd_devel@lists.sourceforge.net>
11 *
12 * Device driver for TCG/TCPA TPM (trusted platform module).
13 * Specifications at www.trustedcomputinggroup.org
14 *
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation, version 2 of the
18 * License.
19 *
20 * Note, the TPM chip is not interrupt driven (only polling)
21 * and can have very long timeouts (minutes!). Hence the unusual
22 * calls to msleep.
23 *
24 */
25
26 #include <linux/sched.h>
27 #include <linux/poll.h>
28 #include <linux/spinlock.h>
29 #include "tpm.h"
30
31 enum tpm_const {
32 TPM_MINOR = 224, /* officially assigned */
33 TPM_BUFSIZE = 2048,
34 TPM_NUM_DEVICES = 256,
35 TPM_NUM_MASK_ENTRIES = TPM_NUM_DEVICES / (8 * sizeof(int))
36 };
37
38 static LIST_HEAD(tpm_chip_list);
39 static DEFINE_SPINLOCK(driver_lock);
40 static int dev_mask[TPM_NUM_MASK_ENTRIES];
41
42 static void user_reader_timeout(unsigned long ptr)
43 {
44 struct tpm_chip *chip = (struct tpm_chip *) ptr;
45
46 down(&chip->buffer_mutex);
47 atomic_set(&chip->data_pending, 0);
48 memset(chip->data_buffer, 0, TPM_BUFSIZE);
49 up(&chip->buffer_mutex);
50 }
51
52 /*
53 * Internal kernel interface to transmit TPM commands
54 */
55 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
56 size_t bufsiz)
57 {
58 ssize_t rc;
59 u32 count;
60 unsigned long stop;
61
62 count = be32_to_cpu(*((__be32 *) (buf + 2)));
63
64 if (count == 0)
65 return -ENODATA;
66 if (count > bufsiz) {
67 dev_err(&chip->pci_dev->dev,
68 "invalid count value %x %zx \n", count, bufsiz);
69 return -E2BIG;
70 }
71
72 down(&chip->tpm_mutex);
73
74 if ((rc = chip->vendor->send(chip, (u8 *) buf, count)) < 0) {
75 dev_err(&chip->pci_dev->dev,
76 "tpm_transmit: tpm_send: error %zd\n", rc);
77 goto out;
78 }
79
80 stop = jiffies + 2 * 60 * HZ;
81 do {
82 u8 status = inb(chip->vendor->base + 1);
83 if ((status & chip->vendor->req_complete_mask) ==
84 chip->vendor->req_complete_val) {
85 goto out_recv;
86 }
87
88 if ((status == chip->vendor->req_canceled)) {
89 dev_err(&chip->pci_dev->dev, "Operation Canceled\n");
90 rc = -ECANCELED;
91 goto out;
92 }
93
94 msleep(TPM_TIMEOUT); /* CHECK */
95 rmb();
96 } while (time_before(jiffies, stop));
97
98
99 chip->vendor->cancel(chip);
100 dev_err(&chip->pci_dev->dev, "Operation Timed out\n");
101 rc = -ETIME;
102 goto out;
103
104 out_recv:
105 rc = chip->vendor->recv(chip, (u8 *) buf, bufsiz);
106 if (rc < 0)
107 dev_err(&chip->pci_dev->dev,
108 "tpm_transmit: tpm_recv: error %zd\n", rc);
109 out:
110 up(&chip->tpm_mutex);
111 return rc;
112 }
113
114 #define TPM_DIGEST_SIZE 20
115 #define CAP_PCR_RESULT_SIZE 18
116 static const u8 cap_pcr[] = {
117 0, 193, /* TPM_TAG_RQU_COMMAND */
118 0, 0, 0, 22, /* length */
119 0, 0, 0, 101, /* TPM_ORD_GetCapability */
120 0, 0, 0, 5,
121 0, 0, 0, 4,
122 0, 0, 1, 1
123 };
124
125 #define READ_PCR_RESULT_SIZE 30
126 static const u8 pcrread[] = {
127 0, 193, /* TPM_TAG_RQU_COMMAND */
128 0, 0, 0, 14, /* length */
129 0, 0, 0, 21, /* TPM_ORD_PcrRead */
130 0, 0, 0, 0 /* PCR index */
131 };
132
133 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
134 char *buf)
135 {
136 u8 data[READ_PCR_RESULT_SIZE];
137 ssize_t len;
138 int i, j, num_pcrs;
139 __be32 index;
140 char *str = buf;
141
142 struct tpm_chip *chip =
143 pci_get_drvdata(to_pci_dev(dev));
144 if (chip == NULL)
145 return -ENODEV;
146
147 memcpy(data, cap_pcr, sizeof(cap_pcr));
148 if ((len = tpm_transmit(chip, data, sizeof(data)))
149 < CAP_PCR_RESULT_SIZE) {
150 dev_dbg(&chip->pci_dev->dev, "A TPM error (%d) occurred "
151 "attempting to determine the number of PCRS\n",
152 be32_to_cpu(*((__be32 *) (data + 6))));
153 return 0;
154 }
155
156 num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
157
158 for (i = 0; i < num_pcrs; i++) {
159 memcpy(data, pcrread, sizeof(pcrread));
160 index = cpu_to_be32(i);
161 memcpy(data + 10, &index, 4);
162 if ((len = tpm_transmit(chip, data, sizeof(data)))
163 < READ_PCR_RESULT_SIZE){
164 dev_dbg(&chip->pci_dev->dev, "A TPM error (%d) occurred"
165 " attempting to read PCR %d of %d\n",
166 be32_to_cpu(*((__be32 *) (data + 6))), i, num_pcrs);
167 goto out;
168 }
169 str += sprintf(str, "PCR-%02d: ", i);
170 for (j = 0; j < TPM_DIGEST_SIZE; j++)
171 str += sprintf(str, "%02X ", *(data + 10 + j));
172 str += sprintf(str, "\n");
173 }
174 out:
175 return str - buf;
176 }
177 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
178
179 #define READ_PUBEK_RESULT_SIZE 314
180 static const u8 readpubek[] = {
181 0, 193, /* TPM_TAG_RQU_COMMAND */
182 0, 0, 0, 30, /* length */
183 0, 0, 0, 124, /* TPM_ORD_ReadPubek */
184 };
185
186 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
187 char *buf)
188 {
189 u8 *data;
190 ssize_t len;
191 int i, rc;
192 char *str = buf;
193
194 struct tpm_chip *chip =
195 pci_get_drvdata(to_pci_dev(dev));
196 if (chip == NULL)
197 return -ENODEV;
198
199 data = kmalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
200 if (!data)
201 return -ENOMEM;
202
203 memcpy(data, readpubek, sizeof(readpubek));
204 memset(data + sizeof(readpubek), 0, 20); /* zero nonce */
205
206 if ((len = tpm_transmit(chip, data, READ_PUBEK_RESULT_SIZE)) <
207 READ_PUBEK_RESULT_SIZE) {
208 dev_dbg(&chip->pci_dev->dev, "A TPM error (%d) occurred "
209 "attempting to read the PUBEK\n",
210 be32_to_cpu(*((__be32 *) (data + 6))));
211 rc = 0;
212 goto out;
213 }
214
215 /*
216 ignore header 10 bytes
217 algorithm 32 bits (1 == RSA )
218 encscheme 16 bits
219 sigscheme 16 bits
220 parameters (RSA 12->bytes: keybit, #primes, expbit)
221 keylenbytes 32 bits
222 256 byte modulus
223 ignore checksum 20 bytes
224 */
225
226 str +=
227 sprintf(str,
228 "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
229 "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
230 " %02X %02X %02X %02X %02X %02X %02X %02X\n"
231 "Modulus length: %d\nModulus: \n",
232 data[10], data[11], data[12], data[13], data[14],
233 data[15], data[16], data[17], data[22], data[23],
234 data[24], data[25], data[26], data[27], data[28],
235 data[29], data[30], data[31], data[32], data[33],
236 be32_to_cpu(*((__be32 *) (data + 34))));
237
238 for (i = 0; i < 256; i++) {
239 str += sprintf(str, "%02X ", data[i + 38]);
240 if ((i + 1) % 16 == 0)
241 str += sprintf(str, "\n");
242 }
243 rc = str - buf;
244 out:
245 kfree(data);
246 return rc;
247 }
248
249 EXPORT_SYMBOL_GPL(tpm_show_pubek);
250
251 #define CAP_VER_RESULT_SIZE 18
252 static const u8 cap_version[] = {
253 0, 193, /* TPM_TAG_RQU_COMMAND */
254 0, 0, 0, 18, /* length */
255 0, 0, 0, 101, /* TPM_ORD_GetCapability */
256 0, 0, 0, 6,
257 0, 0, 0, 0
258 };
259
260 #define CAP_MANUFACTURER_RESULT_SIZE 18
261 static const u8 cap_manufacturer[] = {
262 0, 193, /* TPM_TAG_RQU_COMMAND */
263 0, 0, 0, 22, /* length */
264 0, 0, 0, 101, /* TPM_ORD_GetCapability */
265 0, 0, 0, 5,
266 0, 0, 0, 4,
267 0, 0, 1, 3
268 };
269
270 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
271 char *buf)
272 {
273 u8 data[sizeof(cap_manufacturer)];
274 ssize_t len;
275 char *str = buf;
276
277 struct tpm_chip *chip =
278 pci_get_drvdata(to_pci_dev(dev));
279 if (chip == NULL)
280 return -ENODEV;
281
282 memcpy(data, cap_manufacturer, sizeof(cap_manufacturer));
283
284 if ((len = tpm_transmit(chip, data, sizeof(data))) <
285 CAP_MANUFACTURER_RESULT_SIZE)
286 return len;
287
288 str += sprintf(str, "Manufacturer: 0x%x\n",
289 be32_to_cpu(*((__be32 *) (data + 14))));
290
291 memcpy(data, cap_version, sizeof(cap_version));
292
293 if ((len = tpm_transmit(chip, data, sizeof(data))) <
294 CAP_VER_RESULT_SIZE)
295 return len;
296
297 str +=
298 sprintf(str, "TCG version: %d.%d\nFirmware version: %d.%d\n",
299 (int) data[14], (int) data[15], (int) data[16],
300 (int) data[17]);
301
302 return str - buf;
303 }
304 EXPORT_SYMBOL_GPL(tpm_show_caps);
305
306 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
307 const char *buf, size_t count)
308 {
309 struct tpm_chip *chip = dev_get_drvdata(dev);
310 if (chip == NULL)
311 return 0;
312
313 chip->vendor->cancel(chip);
314 return count;
315 }
316 EXPORT_SYMBOL_GPL(tpm_store_cancel);
317
318
319 /*
320 * Device file system interface to the TPM
321 */
322 int tpm_open(struct inode *inode, struct file *file)
323 {
324 int rc = 0, minor = iminor(inode);
325 struct tpm_chip *chip = NULL, *pos;
326
327 spin_lock(&driver_lock);
328
329 list_for_each_entry(pos, &tpm_chip_list, list) {
330 if (pos->vendor->miscdev.minor == minor) {
331 chip = pos;
332 break;
333 }
334 }
335
336 if (chip == NULL) {
337 rc = -ENODEV;
338 goto err_out;
339 }
340
341 if (chip->num_opens) {
342 dev_dbg(&chip->pci_dev->dev,
343 "Another process owns this TPM\n");
344 rc = -EBUSY;
345 goto err_out;
346 }
347
348 chip->num_opens++;
349 pci_dev_get(chip->pci_dev);
350
351 spin_unlock(&driver_lock);
352
353 chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
354 if (chip->data_buffer == NULL) {
355 chip->num_opens--;
356 pci_dev_put(chip->pci_dev);
357 return -ENOMEM;
358 }
359
360 atomic_set(&chip->data_pending, 0);
361
362 file->private_data = chip;
363 return 0;
364
365 err_out:
366 spin_unlock(&driver_lock);
367 return rc;
368 }
369
370 EXPORT_SYMBOL_GPL(tpm_open);
371
372 int tpm_release(struct inode *inode, struct file *file)
373 {
374 struct tpm_chip *chip = file->private_data;
375
376 spin_lock(&driver_lock);
377 file->private_data = NULL;
378 chip->num_opens--;
379 del_singleshot_timer_sync(&chip->user_read_timer);
380 atomic_set(&chip->data_pending, 0);
381 pci_dev_put(chip->pci_dev);
382 kfree(chip->data_buffer);
383 spin_unlock(&driver_lock);
384 return 0;
385 }
386
387 EXPORT_SYMBOL_GPL(tpm_release);
388
389 ssize_t tpm_write(struct file * file, const char __user * buf,
390 size_t size, loff_t * off)
391 {
392 struct tpm_chip *chip = file->private_data;
393 int in_size = size, out_size;
394
395 /* cannot perform a write until the read has cleared
396 either via tpm_read or a user_read_timer timeout */
397 while (atomic_read(&chip->data_pending) != 0)
398 msleep(TPM_TIMEOUT);
399
400 down(&chip->buffer_mutex);
401
402 if (in_size > TPM_BUFSIZE)
403 in_size = TPM_BUFSIZE;
404
405 if (copy_from_user
406 (chip->data_buffer, (void __user *) buf, in_size)) {
407 up(&chip->buffer_mutex);
408 return -EFAULT;
409 }
410
411 /* atomic tpm command send and result receive */
412 out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
413
414 atomic_set(&chip->data_pending, out_size);
415 up(&chip->buffer_mutex);
416
417 /* Set a timeout by which the reader must come claim the result */
418 mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
419
420 return in_size;
421 }
422
423 EXPORT_SYMBOL_GPL(tpm_write);
424
425 ssize_t tpm_read(struct file * file, char __user * buf,
426 size_t size, loff_t * off)
427 {
428 struct tpm_chip *chip = file->private_data;
429 int ret_size;
430
431 del_singleshot_timer_sync(&chip->user_read_timer);
432 ret_size = atomic_read(&chip->data_pending);
433 atomic_set(&chip->data_pending, 0);
434 if (ret_size > 0) { /* relay data */
435 if (size < ret_size)
436 ret_size = size;
437
438 down(&chip->buffer_mutex);
439 if (copy_to_user
440 ((void __user *) buf, chip->data_buffer, ret_size))
441 ret_size = -EFAULT;
442 up(&chip->buffer_mutex);
443 }
444
445 return ret_size;
446 }
447
448 EXPORT_SYMBOL_GPL(tpm_read);
449
450 void __devexit tpm_remove(struct pci_dev *pci_dev)
451 {
452 struct tpm_chip *chip = pci_get_drvdata(pci_dev);
453
454 if (chip == NULL) {
455 dev_err(&pci_dev->dev, "No device data found\n");
456 return;
457 }
458
459 spin_lock(&driver_lock);
460
461 list_del(&chip->list);
462
463 spin_unlock(&driver_lock);
464
465 pci_set_drvdata(pci_dev, NULL);
466 misc_deregister(&chip->vendor->miscdev);
467 kfree(chip->vendor->miscdev.name);
468
469 sysfs_remove_group(&pci_dev->dev.kobj, chip->vendor->attr_group);
470
471 pci_disable_device(pci_dev);
472
473 dev_mask[chip->dev_num / TPM_NUM_MASK_ENTRIES ] &= !(1 << (chip->dev_num % TPM_NUM_MASK_ENTRIES));
474
475 kfree(chip);
476
477 pci_dev_put(pci_dev);
478 }
479
480 EXPORT_SYMBOL_GPL(tpm_remove);
481
482 static u8 savestate[] = {
483 0, 193, /* TPM_TAG_RQU_COMMAND */
484 0, 0, 0, 10, /* blob length (in bytes) */
485 0, 0, 0, 152 /* TPM_ORD_SaveState */
486 };
487
488 /*
489 * We are about to suspend. Save the TPM state
490 * so that it can be restored.
491 */
492 int tpm_pm_suspend(struct pci_dev *pci_dev, pm_message_t pm_state)
493 {
494 struct tpm_chip *chip = pci_get_drvdata(pci_dev);
495 if (chip == NULL)
496 return -ENODEV;
497
498 tpm_transmit(chip, savestate, sizeof(savestate));
499 return 0;
500 }
501
502 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
503
504 /*
505 * Resume from a power safe. The BIOS already restored
506 * the TPM state.
507 */
508 int tpm_pm_resume(struct pci_dev *pci_dev)
509 {
510 struct tpm_chip *chip = pci_get_drvdata(pci_dev);
511
512 if (chip == NULL)
513 return -ENODEV;
514
515 return 0;
516 }
517
518 EXPORT_SYMBOL_GPL(tpm_pm_resume);
519
520 /*
521 * Called from tpm_<specific>.c probe function only for devices
522 * the driver has determined it should claim. Prior to calling
523 * this function the specific probe function has called pci_enable_device
524 * upon errant exit from this function specific probe function should call
525 * pci_disable_device
526 */
527 int tpm_register_hardware(struct pci_dev *pci_dev,
528 struct tpm_vendor_specific *entry)
529 {
530 #define DEVNAME_SIZE 7
531
532 char *devname;
533 struct tpm_chip *chip;
534 int i, j;
535
536 /* Driver specific per-device data */
537 chip = kmalloc(sizeof(*chip), GFP_KERNEL);
538 if (chip == NULL)
539 return -ENOMEM;
540
541 memset(chip, 0, sizeof(struct tpm_chip));
542
543 init_MUTEX(&chip->buffer_mutex);
544 init_MUTEX(&chip->tpm_mutex);
545 INIT_LIST_HEAD(&chip->list);
546
547 init_timer(&chip->user_read_timer);
548 chip->user_read_timer.function = user_reader_timeout;
549 chip->user_read_timer.data = (unsigned long) chip;
550
551 chip->vendor = entry;
552
553 chip->dev_num = -1;
554
555 for (i = 0; i < TPM_NUM_MASK_ENTRIES; i++)
556 for (j = 0; j < 8 * sizeof(int); j++)
557 if ((dev_mask[i] & (1 << j)) == 0) {
558 chip->dev_num =
559 i * TPM_NUM_MASK_ENTRIES + j;
560 dev_mask[i] |= 1 << j;
561 goto dev_num_search_complete;
562 }
563
564 dev_num_search_complete:
565 if (chip->dev_num < 0) {
566 dev_err(&pci_dev->dev,
567 "No available tpm device numbers\n");
568 kfree(chip);
569 return -ENODEV;
570 } else if (chip->dev_num == 0)
571 chip->vendor->miscdev.minor = TPM_MINOR;
572 else
573 chip->vendor->miscdev.minor = MISC_DYNAMIC_MINOR;
574
575 devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
576 scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
577 chip->vendor->miscdev.name = devname;
578
579 chip->vendor->miscdev.dev = &(pci_dev->dev);
580 chip->pci_dev = pci_dev_get(pci_dev);
581
582 if (misc_register(&chip->vendor->miscdev)) {
583 dev_err(&chip->pci_dev->dev,
584 "unable to misc_register %s, minor %d\n",
585 chip->vendor->miscdev.name,
586 chip->vendor->miscdev.minor);
587 pci_dev_put(pci_dev);
588 kfree(chip);
589 dev_mask[i] &= !(1 << j);
590 return -ENODEV;
591 }
592
593 spin_lock(&driver_lock);
594
595 pci_set_drvdata(pci_dev, chip);
596
597 list_add(&chip->list, &tpm_chip_list);
598
599 spin_unlock(&driver_lock);
600
601 sysfs_create_group(&pci_dev->dev.kobj, chip->vendor->attr_group);
602
603 return 0;
604 }
605
606 EXPORT_SYMBOL_GPL(tpm_register_hardware);
607
608 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
609 MODULE_DESCRIPTION("TPM Driver");
610 MODULE_VERSION("2.0");
611 MODULE_LICENSE("GPL");
Support for the Chinese Samsung S3C2440 based development boards