disable some mediatekl custom warnings
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / char / tpm / tpm.c
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/poll.h>
27 #include <linux/slab.h>
28 #include <linux/mutex.h>
29 #include <linux/spinlock.h>
30 #include <linux/freezer.h>
31
32 #include "tpm.h"
33 #include "tpm_eventlog.h"
34
35 enum tpm_duration {
36 TPM_SHORT = 0,
37 TPM_MEDIUM = 1,
38 TPM_LONG = 2,
39 TPM_UNDEFINED,
40 };
41
42 #define TPM_MAX_ORDINAL 243
43 #define TSC_MAX_ORDINAL 12
44 #define TPM_PROTECTED_COMMAND 0x00
45 #define TPM_CONNECTION_COMMAND 0x40
46
47 /*
48 * Bug workaround - some TPM's don't flush the most
49 * recently changed pcr on suspend, so force the flush
50 * with an extend to the selected _unused_ non-volatile pcr.
51 */
52 static int tpm_suspend_pcr;
53 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
54 MODULE_PARM_DESC(suspend_pcr,
55 "PCR to use for dummy writes to faciltate flush on suspend.");
56
57 static LIST_HEAD(tpm_chip_list);
58 static DEFINE_SPINLOCK(driver_lock);
59 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
60
61 /*
62 * Array with one entry per ordinal defining the maximum amount
63 * of time the chip could take to return the result. The ordinal
64 * designation of short, medium or long is defined in a table in
65 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
66 * values of the SHORT, MEDIUM, and LONG durations are retrieved
67 * from the chip during initialization with a call to tpm_get_timeouts.
68 */
69 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
70 TPM_UNDEFINED, /* 0 */
71 TPM_UNDEFINED,
72 TPM_UNDEFINED,
73 TPM_UNDEFINED,
74 TPM_UNDEFINED,
75 TPM_UNDEFINED, /* 5 */
76 TPM_UNDEFINED,
77 TPM_UNDEFINED,
78 TPM_UNDEFINED,
79 TPM_UNDEFINED,
80 TPM_SHORT, /* 10 */
81 TPM_SHORT,
82 TPM_MEDIUM,
83 TPM_LONG,
84 TPM_LONG,
85 TPM_MEDIUM, /* 15 */
86 TPM_SHORT,
87 TPM_SHORT,
88 TPM_MEDIUM,
89 TPM_LONG,
90 TPM_SHORT, /* 20 */
91 TPM_SHORT,
92 TPM_MEDIUM,
93 TPM_MEDIUM,
94 TPM_MEDIUM,
95 TPM_SHORT, /* 25 */
96 TPM_SHORT,
97 TPM_MEDIUM,
98 TPM_SHORT,
99 TPM_SHORT,
100 TPM_MEDIUM, /* 30 */
101 TPM_LONG,
102 TPM_MEDIUM,
103 TPM_SHORT,
104 TPM_SHORT,
105 TPM_SHORT, /* 35 */
106 TPM_MEDIUM,
107 TPM_MEDIUM,
108 TPM_UNDEFINED,
109 TPM_UNDEFINED,
110 TPM_MEDIUM, /* 40 */
111 TPM_LONG,
112 TPM_MEDIUM,
113 TPM_SHORT,
114 TPM_SHORT,
115 TPM_SHORT, /* 45 */
116 TPM_SHORT,
117 TPM_SHORT,
118 TPM_SHORT,
119 TPM_LONG,
120 TPM_MEDIUM, /* 50 */
121 TPM_MEDIUM,
122 TPM_UNDEFINED,
123 TPM_UNDEFINED,
124 TPM_UNDEFINED,
125 TPM_UNDEFINED, /* 55 */
126 TPM_UNDEFINED,
127 TPM_UNDEFINED,
128 TPM_UNDEFINED,
129 TPM_UNDEFINED,
130 TPM_MEDIUM, /* 60 */
131 TPM_MEDIUM,
132 TPM_MEDIUM,
133 TPM_SHORT,
134 TPM_SHORT,
135 TPM_MEDIUM, /* 65 */
136 TPM_UNDEFINED,
137 TPM_UNDEFINED,
138 TPM_UNDEFINED,
139 TPM_UNDEFINED,
140 TPM_SHORT, /* 70 */
141 TPM_SHORT,
142 TPM_UNDEFINED,
143 TPM_UNDEFINED,
144 TPM_UNDEFINED,
145 TPM_UNDEFINED, /* 75 */
146 TPM_UNDEFINED,
147 TPM_UNDEFINED,
148 TPM_UNDEFINED,
149 TPM_UNDEFINED,
150 TPM_LONG, /* 80 */
151 TPM_UNDEFINED,
152 TPM_MEDIUM,
153 TPM_LONG,
154 TPM_SHORT,
155 TPM_UNDEFINED, /* 85 */
156 TPM_UNDEFINED,
157 TPM_UNDEFINED,
158 TPM_UNDEFINED,
159 TPM_UNDEFINED,
160 TPM_SHORT, /* 90 */
161 TPM_SHORT,
162 TPM_SHORT,
163 TPM_SHORT,
164 TPM_SHORT,
165 TPM_UNDEFINED, /* 95 */
166 TPM_UNDEFINED,
167 TPM_UNDEFINED,
168 TPM_UNDEFINED,
169 TPM_UNDEFINED,
170 TPM_MEDIUM, /* 100 */
171 TPM_SHORT,
172 TPM_SHORT,
173 TPM_UNDEFINED,
174 TPM_UNDEFINED,
175 TPM_UNDEFINED, /* 105 */
176 TPM_UNDEFINED,
177 TPM_UNDEFINED,
178 TPM_UNDEFINED,
179 TPM_UNDEFINED,
180 TPM_SHORT, /* 110 */
181 TPM_SHORT,
182 TPM_SHORT,
183 TPM_SHORT,
184 TPM_SHORT,
185 TPM_SHORT, /* 115 */
186 TPM_SHORT,
187 TPM_SHORT,
188 TPM_UNDEFINED,
189 TPM_UNDEFINED,
190 TPM_LONG, /* 120 */
191 TPM_LONG,
192 TPM_MEDIUM,
193 TPM_UNDEFINED,
194 TPM_SHORT,
195 TPM_SHORT, /* 125 */
196 TPM_SHORT,
197 TPM_LONG,
198 TPM_SHORT,
199 TPM_SHORT,
200 TPM_SHORT, /* 130 */
201 TPM_MEDIUM,
202 TPM_UNDEFINED,
203 TPM_SHORT,
204 TPM_MEDIUM,
205 TPM_UNDEFINED, /* 135 */
206 TPM_UNDEFINED,
207 TPM_UNDEFINED,
208 TPM_UNDEFINED,
209 TPM_UNDEFINED,
210 TPM_SHORT, /* 140 */
211 TPM_SHORT,
212 TPM_UNDEFINED,
213 TPM_UNDEFINED,
214 TPM_UNDEFINED,
215 TPM_UNDEFINED, /* 145 */
216 TPM_UNDEFINED,
217 TPM_UNDEFINED,
218 TPM_UNDEFINED,
219 TPM_UNDEFINED,
220 TPM_SHORT, /* 150 */
221 TPM_MEDIUM,
222 TPM_MEDIUM,
223 TPM_SHORT,
224 TPM_SHORT,
225 TPM_UNDEFINED, /* 155 */
226 TPM_UNDEFINED,
227 TPM_UNDEFINED,
228 TPM_UNDEFINED,
229 TPM_UNDEFINED,
230 TPM_SHORT, /* 160 */
231 TPM_SHORT,
232 TPM_SHORT,
233 TPM_SHORT,
234 TPM_UNDEFINED,
235 TPM_UNDEFINED, /* 165 */
236 TPM_UNDEFINED,
237 TPM_UNDEFINED,
238 TPM_UNDEFINED,
239 TPM_UNDEFINED,
240 TPM_LONG, /* 170 */
241 TPM_UNDEFINED,
242 TPM_UNDEFINED,
243 TPM_UNDEFINED,
244 TPM_UNDEFINED,
245 TPM_UNDEFINED, /* 175 */
246 TPM_UNDEFINED,
247 TPM_UNDEFINED,
248 TPM_UNDEFINED,
249 TPM_UNDEFINED,
250 TPM_MEDIUM, /* 180 */
251 TPM_SHORT,
252 TPM_MEDIUM,
253 TPM_MEDIUM,
254 TPM_MEDIUM,
255 TPM_MEDIUM, /* 185 */
256 TPM_SHORT,
257 TPM_UNDEFINED,
258 TPM_UNDEFINED,
259 TPM_UNDEFINED,
260 TPM_UNDEFINED, /* 190 */
261 TPM_UNDEFINED,
262 TPM_UNDEFINED,
263 TPM_UNDEFINED,
264 TPM_UNDEFINED,
265 TPM_UNDEFINED, /* 195 */
266 TPM_UNDEFINED,
267 TPM_UNDEFINED,
268 TPM_UNDEFINED,
269 TPM_UNDEFINED,
270 TPM_SHORT, /* 200 */
271 TPM_UNDEFINED,
272 TPM_UNDEFINED,
273 TPM_UNDEFINED,
274 TPM_SHORT,
275 TPM_SHORT, /* 205 */
276 TPM_SHORT,
277 TPM_SHORT,
278 TPM_SHORT,
279 TPM_SHORT,
280 TPM_MEDIUM, /* 210 */
281 TPM_UNDEFINED,
282 TPM_MEDIUM,
283 TPM_MEDIUM,
284 TPM_MEDIUM,
285 TPM_UNDEFINED, /* 215 */
286 TPM_MEDIUM,
287 TPM_UNDEFINED,
288 TPM_UNDEFINED,
289 TPM_SHORT,
290 TPM_SHORT, /* 220 */
291 TPM_SHORT,
292 TPM_SHORT,
293 TPM_SHORT,
294 TPM_SHORT,
295 TPM_UNDEFINED, /* 225 */
296 TPM_UNDEFINED,
297 TPM_UNDEFINED,
298 TPM_UNDEFINED,
299 TPM_UNDEFINED,
300 TPM_SHORT, /* 230 */
301 TPM_LONG,
302 TPM_MEDIUM,
303 TPM_UNDEFINED,
304 TPM_UNDEFINED,
305 TPM_UNDEFINED, /* 235 */
306 TPM_UNDEFINED,
307 TPM_UNDEFINED,
308 TPM_UNDEFINED,
309 TPM_UNDEFINED,
310 TPM_SHORT, /* 240 */
311 TPM_UNDEFINED,
312 TPM_MEDIUM,
313 };
314
315 static void user_reader_timeout(unsigned long ptr)
316 {
317 struct tpm_chip *chip = (struct tpm_chip *) ptr;
318
319 schedule_work(&chip->work);
320 }
321
322 static void timeout_work(struct work_struct *work)
323 {
324 struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
325
326 mutex_lock(&chip->buffer_mutex);
327 atomic_set(&chip->data_pending, 0);
328 memset(chip->data_buffer, 0, TPM_BUFSIZE);
329 mutex_unlock(&chip->buffer_mutex);
330 }
331
332 /*
333 * Returns max number of jiffies to wait
334 */
335 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
336 u32 ordinal)
337 {
338 int duration_idx = TPM_UNDEFINED;
339 int duration = 0;
340 u8 category = (ordinal >> 24) & 0xFF;
341
342 if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) ||
343 (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL))
344 duration_idx = tpm_ordinal_duration[ordinal];
345
346 if (duration_idx != TPM_UNDEFINED)
347 duration = chip->vendor.duration[duration_idx];
348 if (duration <= 0)
349 return 2 * 60 * HZ;
350 else
351 return duration;
352 }
353 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
354
355 /*
356 * Internal kernel interface to transmit TPM commands
357 */
358 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
359 size_t bufsiz)
360 {
361 ssize_t rc;
362 u32 count, ordinal;
363 unsigned long stop;
364
365 if (bufsiz > TPM_BUFSIZE)
366 bufsiz = TPM_BUFSIZE;
367
368 count = be32_to_cpu(*((__be32 *) (buf + 2)));
369 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
370 if (count == 0)
371 return -ENODATA;
372 if (count > bufsiz) {
373 dev_err(chip->dev,
374 "invalid count value %x %zx \n", count, bufsiz);
375 return -E2BIG;
376 }
377
378 mutex_lock(&chip->tpm_mutex);
379
380 if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
381 dev_err(chip->dev,
382 "tpm_transmit: tpm_send: error %zd\n", rc);
383 goto out;
384 }
385
386 if (chip->vendor.irq)
387 goto out_recv;
388
389 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
390 do {
391 u8 status = chip->vendor.status(chip);
392 if ((status & chip->vendor.req_complete_mask) ==
393 chip->vendor.req_complete_val)
394 goto out_recv;
395
396 if (chip->vendor.req_canceled(chip, status)) {
397 dev_err(chip->dev, "Operation Canceled\n");
398 rc = -ECANCELED;
399 goto out;
400 }
401
402 msleep(TPM_TIMEOUT); /* CHECK */
403 rmb();
404 } while (time_before(jiffies, stop));
405
406 chip->vendor.cancel(chip);
407 dev_err(chip->dev, "Operation Timed out\n");
408 rc = -ETIME;
409 goto out;
410
411 out_recv:
412 rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
413 if (rc < 0)
414 dev_err(chip->dev,
415 "tpm_transmit: tpm_recv: error %zd\n", rc);
416 out:
417 mutex_unlock(&chip->tpm_mutex);
418 return rc;
419 }
420
421 #define TPM_DIGEST_SIZE 20
422 #define TPM_RET_CODE_IDX 6
423
424 enum tpm_capabilities {
425 TPM_CAP_FLAG = cpu_to_be32(4),
426 TPM_CAP_PROP = cpu_to_be32(5),
427 CAP_VERSION_1_1 = cpu_to_be32(0x06),
428 CAP_VERSION_1_2 = cpu_to_be32(0x1A)
429 };
430
431 enum tpm_sub_capabilities {
432 TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
433 TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
434 TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
435 TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
436 TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
437 TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
438 TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
439
440 };
441
442 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
443 int len, const char *desc)
444 {
445 int err;
446
447 len = tpm_transmit(chip,(u8 *) cmd, len);
448 if (len < 0)
449 return len;
450 else if (len < TPM_HEADER_SIZE)
451 return -EFAULT;
452
453 err = be32_to_cpu(cmd->header.out.return_code);
454 if (err != 0 && desc)
455 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
456
457 return err;
458 }
459
460 #define TPM_INTERNAL_RESULT_SIZE 200
461 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
462 #define TPM_ORD_GET_CAP cpu_to_be32(101)
463 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
464
465 static const struct tpm_input_header tpm_getcap_header = {
466 .tag = TPM_TAG_RQU_COMMAND,
467 .length = cpu_to_be32(22),
468 .ordinal = TPM_ORD_GET_CAP
469 };
470
471 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
472 const char *desc)
473 {
474 struct tpm_cmd_t tpm_cmd;
475 int rc;
476 struct tpm_chip *chip = dev_get_drvdata(dev);
477
478 tpm_cmd.header.in = tpm_getcap_header;
479 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
480 tpm_cmd.params.getcap_in.cap = subcap_id;
481 /*subcap field not necessary */
482 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
483 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
484 } else {
485 if (subcap_id == TPM_CAP_FLAG_PERM ||
486 subcap_id == TPM_CAP_FLAG_VOL)
487 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
488 else
489 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
490 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
491 tpm_cmd.params.getcap_in.subcap = subcap_id;
492 }
493 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
494 if (!rc)
495 *cap = tpm_cmd.params.getcap_out.cap;
496 return rc;
497 }
498
499 void tpm_gen_interrupt(struct tpm_chip *chip)
500 {
501 struct tpm_cmd_t tpm_cmd;
502 ssize_t rc;
503
504 tpm_cmd.header.in = tpm_getcap_header;
505 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
506 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
507 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
508
509 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
510 "attempting to determine the timeouts");
511 }
512 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
513
514 #define TPM_ORD_STARTUP cpu_to_be32(153)
515 #define TPM_ST_CLEAR cpu_to_be16(1)
516 #define TPM_ST_STATE cpu_to_be16(2)
517 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
518 static const struct tpm_input_header tpm_startup_header = {
519 .tag = TPM_TAG_RQU_COMMAND,
520 .length = cpu_to_be32(12),
521 .ordinal = TPM_ORD_STARTUP
522 };
523
524 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
525 {
526 struct tpm_cmd_t start_cmd;
527 start_cmd.header.in = tpm_startup_header;
528 start_cmd.params.startup_in.startup_type = startup_type;
529 return transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
530 "attempting to start the TPM");
531 }
532
533 int tpm_get_timeouts(struct tpm_chip *chip)
534 {
535 struct tpm_cmd_t tpm_cmd;
536 struct timeout_t *timeout_cap;
537 struct duration_t *duration_cap;
538 ssize_t rc;
539 u32 timeout;
540 unsigned int scale = 1;
541
542 tpm_cmd.header.in = tpm_getcap_header;
543 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
544 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
545 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
546 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
547
548 if (rc == TPM_ERR_INVALID_POSTINIT) {
549 /* The TPM is not started, we are the first to talk to it.
550 Execute a startup command. */
551 dev_info(chip->dev, "Issuing TPM_STARTUP");
552 if (tpm_startup(chip, TPM_ST_CLEAR))
553 return rc;
554
555 tpm_cmd.header.in = tpm_getcap_header;
556 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
557 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
558 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
559 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
560 NULL);
561 }
562 if (rc) {
563 dev_err(chip->dev,
564 "A TPM error (%zd) occurred attempting to determine the timeouts\n",
565 rc);
566 goto duration;
567 }
568
569 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
570 be32_to_cpu(tpm_cmd.header.out.length)
571 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
572 return -EINVAL;
573
574 timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
575 /* Don't overwrite default if value is 0 */
576 timeout = be32_to_cpu(timeout_cap->a);
577 if (timeout && timeout < 1000) {
578 /* timeouts in msec rather usec */
579 scale = 1000;
580 chip->vendor.timeout_adjusted = true;
581 }
582 if (timeout)
583 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
584 timeout = be32_to_cpu(timeout_cap->b);
585 if (timeout)
586 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
587 timeout = be32_to_cpu(timeout_cap->c);
588 if (timeout)
589 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
590 timeout = be32_to_cpu(timeout_cap->d);
591 if (timeout)
592 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
593
594 duration:
595 tpm_cmd.header.in = tpm_getcap_header;
596 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
597 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
598 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
599
600 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
601 "attempting to determine the durations");
602 if (rc)
603 return rc;
604
605 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
606 be32_to_cpu(tpm_cmd.header.out.length)
607 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
608 return -EINVAL;
609
610 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
611 chip->vendor.duration[TPM_SHORT] =
612 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
613 chip->vendor.duration[TPM_MEDIUM] =
614 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
615 chip->vendor.duration[TPM_LONG] =
616 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
617
618 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
619 * value wrong and apparently reports msecs rather than usecs. So we
620 * fix up the resulting too-small TPM_SHORT value to make things work.
621 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
622 */
623 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
624 chip->vendor.duration[TPM_SHORT] = HZ;
625 chip->vendor.duration[TPM_MEDIUM] *= 1000;
626 chip->vendor.duration[TPM_LONG] *= 1000;
627 chip->vendor.duration_adjusted = true;
628 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
629 }
630 return 0;
631 }
632 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
633
634 #define TPM_ORD_CONTINUE_SELFTEST 83
635 #define CONTINUE_SELFTEST_RESULT_SIZE 10
636
637 static struct tpm_input_header continue_selftest_header = {
638 .tag = TPM_TAG_RQU_COMMAND,
639 .length = cpu_to_be32(10),
640 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
641 };
642
643 /**
644 * tpm_continue_selftest -- run TPM's selftest
645 * @chip: TPM chip to use
646 *
647 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
648 * a TPM error code.
649 */
650 static int tpm_continue_selftest(struct tpm_chip *chip)
651 {
652 int rc;
653 struct tpm_cmd_t cmd;
654
655 cmd.header.in = continue_selftest_header;
656 rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
657 "continue selftest");
658 return rc;
659 }
660
661 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
662 char *buf)
663 {
664 cap_t cap;
665 ssize_t rc;
666
667 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
668 "attempting to determine the permanent enabled state");
669 if (rc)
670 return 0;
671
672 rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
673 return rc;
674 }
675 EXPORT_SYMBOL_GPL(tpm_show_enabled);
676
677 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
678 char *buf)
679 {
680 cap_t cap;
681 ssize_t rc;
682
683 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
684 "attempting to determine the permanent active state");
685 if (rc)
686 return 0;
687
688 rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
689 return rc;
690 }
691 EXPORT_SYMBOL_GPL(tpm_show_active);
692
693 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
694 char *buf)
695 {
696 cap_t cap;
697 ssize_t rc;
698
699 rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
700 "attempting to determine the owner state");
701 if (rc)
702 return 0;
703
704 rc = sprintf(buf, "%d\n", cap.owned);
705 return rc;
706 }
707 EXPORT_SYMBOL_GPL(tpm_show_owned);
708
709 ssize_t tpm_show_temp_deactivated(struct device * dev,
710 struct device_attribute * attr, char *buf)
711 {
712 cap_t cap;
713 ssize_t rc;
714
715 rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
716 "attempting to determine the temporary state");
717 if (rc)
718 return 0;
719
720 rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
721 return rc;
722 }
723 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
724
725 /*
726 * tpm_chip_find_get - return tpm_chip for given chip number
727 */
728 static struct tpm_chip *tpm_chip_find_get(int chip_num)
729 {
730 struct tpm_chip *pos, *chip = NULL;
731
732 rcu_read_lock();
733 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
734 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
735 continue;
736
737 if (try_module_get(pos->dev->driver->owner)) {
738 chip = pos;
739 break;
740 }
741 }
742 rcu_read_unlock();
743 return chip;
744 }
745
746 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
747 #define READ_PCR_RESULT_SIZE 30
748 static struct tpm_input_header pcrread_header = {
749 .tag = TPM_TAG_RQU_COMMAND,
750 .length = cpu_to_be32(14),
751 .ordinal = TPM_ORDINAL_PCRREAD
752 };
753
754 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
755 {
756 int rc;
757 struct tpm_cmd_t cmd;
758
759 cmd.header.in = pcrread_header;
760 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
761 rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
762 "attempting to read a pcr value");
763
764 if (rc == 0)
765 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
766 TPM_DIGEST_SIZE);
767 return rc;
768 }
769
770 /**
771 * tpm_pcr_read - read a pcr value
772 * @chip_num: tpm idx # or ANY
773 * @pcr_idx: pcr idx to retrieve
774 * @res_buf: TPM_PCR value
775 * size of res_buf is 20 bytes (or NULL if you don't care)
776 *
777 * The TPM driver should be built-in, but for whatever reason it
778 * isn't, protect against the chip disappearing, by incrementing
779 * the module usage count.
780 */
781 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
782 {
783 struct tpm_chip *chip;
784 int rc;
785
786 chip = tpm_chip_find_get(chip_num);
787 if (chip == NULL)
788 return -ENODEV;
789 rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
790 tpm_chip_put(chip);
791 return rc;
792 }
793 EXPORT_SYMBOL_GPL(tpm_pcr_read);
794
795 /**
796 * tpm_pcr_extend - extend pcr value with hash
797 * @chip_num: tpm idx # or AN&
798 * @pcr_idx: pcr idx to extend
799 * @hash: hash value used to extend pcr value
800 *
801 * The TPM driver should be built-in, but for whatever reason it
802 * isn't, protect against the chip disappearing, by incrementing
803 * the module usage count.
804 */
805 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
806 #define EXTEND_PCR_RESULT_SIZE 34
807 static struct tpm_input_header pcrextend_header = {
808 .tag = TPM_TAG_RQU_COMMAND,
809 .length = cpu_to_be32(34),
810 .ordinal = TPM_ORD_PCR_EXTEND
811 };
812
813 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
814 {
815 struct tpm_cmd_t cmd;
816 int rc;
817 struct tpm_chip *chip;
818
819 chip = tpm_chip_find_get(chip_num);
820 if (chip == NULL)
821 return -ENODEV;
822
823 cmd.header.in = pcrextend_header;
824 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
825 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
826 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
827 "attempting extend a PCR value");
828
829 tpm_chip_put(chip);
830 return rc;
831 }
832 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
833
834 /**
835 * tpm_do_selftest - have the TPM continue its selftest and wait until it
836 * can receive further commands
837 * @chip: TPM chip to use
838 *
839 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
840 * a TPM error code.
841 */
842 int tpm_do_selftest(struct tpm_chip *chip)
843 {
844 int rc;
845 unsigned int loops;
846 unsigned int delay_msec = 100;
847 unsigned long duration;
848 struct tpm_cmd_t cmd;
849
850 duration = tpm_calc_ordinal_duration(chip,
851 TPM_ORD_CONTINUE_SELFTEST);
852
853 loops = jiffies_to_msecs(duration) / delay_msec;
854
855 rc = tpm_continue_selftest(chip);
856 /* This may fail if there was no TPM driver during a suspend/resume
857 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
858 */
859 if (rc)
860 return rc;
861
862 do {
863 /* Attempt to read a PCR value */
864 cmd.header.in = pcrread_header;
865 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
866 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
867 /* Some buggy TPMs will not respond to tpm_tis_ready() for
868 * around 300ms while the self test is ongoing, keep trying
869 * until the self test duration expires. */
870 if (rc == -ETIME) {
871 dev_info(chip->dev, HW_ERR "TPM command timed out during continue self test");
872 msleep(delay_msec);
873 continue;
874 }
875
876 if (rc < TPM_HEADER_SIZE)
877 return -EFAULT;
878
879 rc = be32_to_cpu(cmd.header.out.return_code);
880 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
881 dev_info(chip->dev,
882 "TPM is disabled/deactivated (0x%X)\n", rc);
883 /* TPM is disabled and/or deactivated; driver can
884 * proceed and TPM does handle commands for
885 * suspend/resume correctly
886 */
887 return 0;
888 }
889 if (rc != TPM_WARN_DOING_SELFTEST)
890 return rc;
891 msleep(delay_msec);
892 } while (--loops > 0);
893
894 return rc;
895 }
896 EXPORT_SYMBOL_GPL(tpm_do_selftest);
897
898 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
899 {
900 struct tpm_chip *chip;
901 int rc;
902
903 chip = tpm_chip_find_get(chip_num);
904 if (chip == NULL)
905 return -ENODEV;
906
907 rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
908
909 tpm_chip_put(chip);
910 return rc;
911 }
912 EXPORT_SYMBOL_GPL(tpm_send);
913
914 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
915 char *buf)
916 {
917 cap_t cap;
918 u8 digest[TPM_DIGEST_SIZE];
919 ssize_t rc;
920 int i, j, num_pcrs;
921 char *str = buf;
922 struct tpm_chip *chip = dev_get_drvdata(dev);
923
924 rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
925 "attempting to determine the number of PCRS");
926 if (rc)
927 return 0;
928
929 num_pcrs = be32_to_cpu(cap.num_pcrs);
930 for (i = 0; i < num_pcrs; i++) {
931 rc = __tpm_pcr_read(chip, i, digest);
932 if (rc)
933 break;
934 str += sprintf(str, "PCR-%02d: ", i);
935 for (j = 0; j < TPM_DIGEST_SIZE; j++)
936 str += sprintf(str, "%02X ", digest[j]);
937 str += sprintf(str, "\n");
938 }
939 return str - buf;
940 }
941 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
942
943 #define READ_PUBEK_RESULT_SIZE 314
944 #define TPM_ORD_READPUBEK cpu_to_be32(124)
945 static struct tpm_input_header tpm_readpubek_header = {
946 .tag = TPM_TAG_RQU_COMMAND,
947 .length = cpu_to_be32(30),
948 .ordinal = TPM_ORD_READPUBEK
949 };
950
951 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
952 char *buf)
953 {
954 u8 *data;
955 struct tpm_cmd_t tpm_cmd;
956 ssize_t err;
957 int i, rc;
958 char *str = buf;
959
960 struct tpm_chip *chip = dev_get_drvdata(dev);
961
962 tpm_cmd.header.in = tpm_readpubek_header;
963 err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
964 "attempting to read the PUBEK");
965 if (err)
966 goto out;
967
968 /*
969 ignore header 10 bytes
970 algorithm 32 bits (1 == RSA )
971 encscheme 16 bits
972 sigscheme 16 bits
973 parameters (RSA 12->bytes: keybit, #primes, expbit)
974 keylenbytes 32 bits
975 256 byte modulus
976 ignore checksum 20 bytes
977 */
978 data = tpm_cmd.params.readpubek_out_buffer;
979 str +=
980 sprintf(str,
981 "Algorithm: %02X %02X %02X %02X\n"
982 "Encscheme: %02X %02X\n"
983 "Sigscheme: %02X %02X\n"
984 "Parameters: %02X %02X %02X %02X "
985 "%02X %02X %02X %02X "
986 "%02X %02X %02X %02X\n"
987 "Modulus length: %d\n"
988 "Modulus:\n",
989 data[0], data[1], data[2], data[3],
990 data[4], data[5],
991 data[6], data[7],
992 data[12], data[13], data[14], data[15],
993 data[16], data[17], data[18], data[19],
994 data[20], data[21], data[22], data[23],
995 be32_to_cpu(*((__be32 *) (data + 24))));
996
997 for (i = 0; i < 256; i++) {
998 str += sprintf(str, "%02X ", data[i + 28]);
999 if ((i + 1) % 16 == 0)
1000 str += sprintf(str, "\n");
1001 }
1002 out:
1003 rc = str - buf;
1004 return rc;
1005 }
1006 EXPORT_SYMBOL_GPL(tpm_show_pubek);
1007
1008
1009 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
1010 char *buf)
1011 {
1012 cap_t cap;
1013 ssize_t rc;
1014 char *str = buf;
1015
1016 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1017 "attempting to determine the manufacturer");
1018 if (rc)
1019 return 0;
1020 str += sprintf(str, "Manufacturer: 0x%x\n",
1021 be32_to_cpu(cap.manufacturer_id));
1022
1023 rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1024 "attempting to determine the 1.1 version");
1025 if (rc)
1026 return 0;
1027 str += sprintf(str,
1028 "TCG version: %d.%d\nFirmware version: %d.%d\n",
1029 cap.tpm_version.Major, cap.tpm_version.Minor,
1030 cap.tpm_version.revMajor, cap.tpm_version.revMinor);
1031 return str - buf;
1032 }
1033 EXPORT_SYMBOL_GPL(tpm_show_caps);
1034
1035 ssize_t tpm_show_caps_1_2(struct device * dev,
1036 struct device_attribute * attr, char *buf)
1037 {
1038 cap_t cap;
1039 ssize_t rc;
1040 char *str = buf;
1041
1042 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1043 "attempting to determine the manufacturer");
1044 if (rc)
1045 return 0;
1046 str += sprintf(str, "Manufacturer: 0x%x\n",
1047 be32_to_cpu(cap.manufacturer_id));
1048 rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1049 "attempting to determine the 1.2 version");
1050 if (rc)
1051 return 0;
1052 str += sprintf(str,
1053 "TCG version: %d.%d\nFirmware version: %d.%d\n",
1054 cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
1055 cap.tpm_version_1_2.revMajor,
1056 cap.tpm_version_1_2.revMinor);
1057 return str - buf;
1058 }
1059 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
1060
1061 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1062 char *buf)
1063 {
1064 struct tpm_chip *chip = dev_get_drvdata(dev);
1065
1066 if (chip->vendor.duration[TPM_LONG] == 0)
1067 return 0;
1068
1069 return sprintf(buf, "%d %d %d [%s]\n",
1070 jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1071 jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1072 jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1073 chip->vendor.duration_adjusted
1074 ? "adjusted" : "original");
1075 }
1076 EXPORT_SYMBOL_GPL(tpm_show_durations);
1077
1078 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1079 char *buf)
1080 {
1081 struct tpm_chip *chip = dev_get_drvdata(dev);
1082
1083 return sprintf(buf, "%d %d %d %d [%s]\n",
1084 jiffies_to_usecs(chip->vendor.timeout_a),
1085 jiffies_to_usecs(chip->vendor.timeout_b),
1086 jiffies_to_usecs(chip->vendor.timeout_c),
1087 jiffies_to_usecs(chip->vendor.timeout_d),
1088 chip->vendor.timeout_adjusted
1089 ? "adjusted" : "original");
1090 }
1091 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1092
1093 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1094 const char *buf, size_t count)
1095 {
1096 struct tpm_chip *chip = dev_get_drvdata(dev);
1097 if (chip == NULL)
1098 return 0;
1099
1100 chip->vendor.cancel(chip);
1101 return count;
1102 }
1103 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1104
1105 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, bool check_cancel,
1106 bool *canceled)
1107 {
1108 u8 status = chip->vendor.status(chip);
1109
1110 *canceled = false;
1111 if ((status & mask) == mask)
1112 return true;
1113 if (check_cancel && chip->vendor.req_canceled(chip, status)) {
1114 *canceled = true;
1115 return true;
1116 }
1117 return false;
1118 }
1119
1120 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1121 wait_queue_head_t *queue, bool check_cancel)
1122 {
1123 unsigned long stop;
1124 long rc;
1125 u8 status;
1126 bool canceled = false;
1127
1128 /* check current status */
1129 status = chip->vendor.status(chip);
1130 if ((status & mask) == mask)
1131 return 0;
1132
1133 stop = jiffies + timeout;
1134
1135 if (chip->vendor.irq) {
1136 again:
1137 timeout = stop - jiffies;
1138 if ((long)timeout <= 0)
1139 return -ETIME;
1140 rc = wait_event_interruptible_timeout(*queue,
1141 wait_for_tpm_stat_cond(chip, mask, check_cancel,
1142 &canceled),
1143 timeout);
1144 if (rc > 0) {
1145 if (canceled)
1146 return -ECANCELED;
1147 return 0;
1148 }
1149 if (rc == -ERESTARTSYS && freezing(current)) {
1150 clear_thread_flag(TIF_SIGPENDING);
1151 goto again;
1152 }
1153 } else {
1154 do {
1155 msleep(TPM_TIMEOUT);
1156 status = chip->vendor.status(chip);
1157 if ((status & mask) == mask)
1158 return 0;
1159 } while (time_before(jiffies, stop));
1160 }
1161 return -ETIME;
1162 }
1163 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1164 /*
1165 * Device file system interface to the TPM
1166 *
1167 * It's assured that the chip will be opened just once,
1168 * by the check of is_open variable, which is protected
1169 * by driver_lock.
1170 */
1171 int tpm_open(struct inode *inode, struct file *file)
1172 {
1173 int minor = iminor(inode);
1174 struct tpm_chip *chip = NULL, *pos;
1175
1176 rcu_read_lock();
1177 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1178 if (pos->vendor.miscdev.minor == minor) {
1179 chip = pos;
1180 get_device(chip->dev);
1181 break;
1182 }
1183 }
1184 rcu_read_unlock();
1185
1186 if (!chip)
1187 return -ENODEV;
1188
1189 if (test_and_set_bit(0, &chip->is_open)) {
1190 dev_dbg(chip->dev, "Another process owns this TPM\n");
1191 put_device(chip->dev);
1192 return -EBUSY;
1193 }
1194
1195 chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1196 if (chip->data_buffer == NULL) {
1197 clear_bit(0, &chip->is_open);
1198 put_device(chip->dev);
1199 return -ENOMEM;
1200 }
1201
1202 atomic_set(&chip->data_pending, 0);
1203
1204 file->private_data = chip;
1205 return 0;
1206 }
1207 EXPORT_SYMBOL_GPL(tpm_open);
1208
1209 /*
1210 * Called on file close
1211 */
1212 int tpm_release(struct inode *inode, struct file *file)
1213 {
1214 struct tpm_chip *chip = file->private_data;
1215
1216 del_singleshot_timer_sync(&chip->user_read_timer);
1217 flush_work(&chip->work);
1218 file->private_data = NULL;
1219 atomic_set(&chip->data_pending, 0);
1220 kzfree(chip->data_buffer);
1221 clear_bit(0, &chip->is_open);
1222 put_device(chip->dev);
1223 return 0;
1224 }
1225 EXPORT_SYMBOL_GPL(tpm_release);
1226
1227 ssize_t tpm_write(struct file *file, const char __user *buf,
1228 size_t size, loff_t *off)
1229 {
1230 struct tpm_chip *chip = file->private_data;
1231 size_t in_size = size;
1232 ssize_t out_size;
1233
1234 /* cannot perform a write until the read has cleared
1235 either via tpm_read or a user_read_timer timeout.
1236 This also prevents splitted buffered writes from blocking here.
1237 */
1238 if (atomic_read(&chip->data_pending) != 0)
1239 return -EBUSY;
1240
1241 if (in_size > TPM_BUFSIZE)
1242 return -E2BIG;
1243
1244 mutex_lock(&chip->buffer_mutex);
1245
1246 if (copy_from_user
1247 (chip->data_buffer, (void __user *) buf, in_size)) {
1248 mutex_unlock(&chip->buffer_mutex);
1249 return -EFAULT;
1250 }
1251
1252 /* atomic tpm command send and result receive */
1253 out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1254 if (out_size < 0) {
1255 mutex_unlock(&chip->buffer_mutex);
1256 return out_size;
1257 }
1258
1259 atomic_set(&chip->data_pending, out_size);
1260 mutex_unlock(&chip->buffer_mutex);
1261
1262 /* Set a timeout by which the reader must come claim the result */
1263 mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1264
1265 return in_size;
1266 }
1267 EXPORT_SYMBOL_GPL(tpm_write);
1268
1269 ssize_t tpm_read(struct file *file, char __user *buf,
1270 size_t size, loff_t *off)
1271 {
1272 struct tpm_chip *chip = file->private_data;
1273 ssize_t ret_size;
1274 int rc;
1275
1276 del_singleshot_timer_sync(&chip->user_read_timer);
1277 flush_work(&chip->work);
1278 ret_size = atomic_read(&chip->data_pending);
1279 if (ret_size > 0) { /* relay data */
1280 ssize_t orig_ret_size = ret_size;
1281 if (size < ret_size)
1282 ret_size = size;
1283
1284 mutex_lock(&chip->buffer_mutex);
1285 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1286 memset(chip->data_buffer, 0, orig_ret_size);
1287 if (rc)
1288 ret_size = -EFAULT;
1289
1290 mutex_unlock(&chip->buffer_mutex);
1291 }
1292
1293 atomic_set(&chip->data_pending, 0);
1294
1295 return ret_size;
1296 }
1297 EXPORT_SYMBOL_GPL(tpm_read);
1298
1299 void tpm_remove_hardware(struct device *dev)
1300 {
1301 struct tpm_chip *chip = dev_get_drvdata(dev);
1302
1303 if (chip == NULL) {
1304 dev_err(dev, "No device data found\n");
1305 return;
1306 }
1307
1308 spin_lock(&driver_lock);
1309 list_del_rcu(&chip->list);
1310 spin_unlock(&driver_lock);
1311 synchronize_rcu();
1312
1313 misc_deregister(&chip->vendor.miscdev);
1314 sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1315 tpm_remove_ppi(&dev->kobj);
1316 tpm_bios_log_teardown(chip->bios_dir);
1317
1318 /* write it this way to be explicit (chip->dev == dev) */
1319 put_device(chip->dev);
1320 }
1321 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1322
1323 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1324 #define SAVESTATE_RESULT_SIZE 10
1325
1326 static struct tpm_input_header savestate_header = {
1327 .tag = TPM_TAG_RQU_COMMAND,
1328 .length = cpu_to_be32(10),
1329 .ordinal = TPM_ORD_SAVESTATE
1330 };
1331
1332 /*
1333 * We are about to suspend. Save the TPM state
1334 * so that it can be restored.
1335 */
1336 int tpm_pm_suspend(struct device *dev)
1337 {
1338 struct tpm_chip *chip = dev_get_drvdata(dev);
1339 struct tpm_cmd_t cmd;
1340 int rc, try;
1341
1342 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1343
1344 if (chip == NULL)
1345 return -ENODEV;
1346
1347 /* for buggy tpm, flush pcrs with extend to selected dummy */
1348 if (tpm_suspend_pcr) {
1349 cmd.header.in = pcrextend_header;
1350 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1351 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1352 TPM_DIGEST_SIZE);
1353 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1354 "extending dummy pcr before suspend");
1355 }
1356
1357 /* now do the actual savestate */
1358 for (try = 0; try < TPM_RETRY; try++) {
1359 cmd.header.in = savestate_header;
1360 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
1361
1362 /*
1363 * If the TPM indicates that it is too busy to respond to
1364 * this command then retry before giving up. It can take
1365 * several seconds for this TPM to be ready.
1366 *
1367 * This can happen if the TPM has already been sent the
1368 * SaveState command before the driver has loaded. TCG 1.2
1369 * specification states that any communication after SaveState
1370 * may cause the TPM to invalidate previously saved state.
1371 */
1372 if (rc != TPM_WARN_RETRY)
1373 break;
1374 msleep(TPM_TIMEOUT_RETRY);
1375 }
1376
1377 if (rc)
1378 dev_err(chip->dev,
1379 "Error (%d) sending savestate before suspend\n", rc);
1380 else if (try > 0)
1381 dev_warn(chip->dev, "TPM savestate took %dms\n",
1382 try * TPM_TIMEOUT_RETRY);
1383
1384 return rc;
1385 }
1386 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1387
1388 /*
1389 * Resume from a power safe. The BIOS already restored
1390 * the TPM state.
1391 */
1392 int tpm_pm_resume(struct device *dev)
1393 {
1394 struct tpm_chip *chip = dev_get_drvdata(dev);
1395
1396 if (chip == NULL)
1397 return -ENODEV;
1398
1399 return 0;
1400 }
1401 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1402
1403 #define TPM_GETRANDOM_RESULT_SIZE 18
1404 static struct tpm_input_header tpm_getrandom_header = {
1405 .tag = TPM_TAG_RQU_COMMAND,
1406 .length = cpu_to_be32(14),
1407 .ordinal = TPM_ORD_GET_RANDOM
1408 };
1409
1410 /**
1411 * tpm_get_random() - Get random bytes from the tpm's RNG
1412 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1413 * @out: destination buffer for the random bytes
1414 * @max: the max number of bytes to write to @out
1415 *
1416 * Returns < 0 on error and the number of bytes read on success
1417 */
1418 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1419 {
1420 struct tpm_chip *chip;
1421 struct tpm_cmd_t tpm_cmd;
1422 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1423 int err, total = 0, retries = 5;
1424 u8 *dest = out;
1425
1426 chip = tpm_chip_find_get(chip_num);
1427 if (chip == NULL)
1428 return -ENODEV;
1429
1430 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1431 return -EINVAL;
1432
1433 do {
1434 tpm_cmd.header.in = tpm_getrandom_header;
1435 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1436
1437 err = transmit_cmd(chip, &tpm_cmd,
1438 TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1439 "attempting get random");
1440 if (err)
1441 break;
1442
1443 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1444 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1445
1446 dest += recd;
1447 total += recd;
1448 num_bytes -= recd;
1449 } while (retries-- && total < max);
1450
1451 return total ? total : -EIO;
1452 }
1453 EXPORT_SYMBOL_GPL(tpm_get_random);
1454
1455 /* In case vendor provided release function, call it too.*/
1456
1457 void tpm_dev_vendor_release(struct tpm_chip *chip)
1458 {
1459 if (!chip)
1460 return;
1461
1462 if (chip->vendor.release)
1463 chip->vendor.release(chip->dev);
1464
1465 clear_bit(chip->dev_num, dev_mask);
1466 kfree(chip->vendor.miscdev.name);
1467 }
1468 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1469
1470
1471 /*
1472 * Once all references to platform device are down to 0,
1473 * release all allocated structures.
1474 */
1475 static void tpm_dev_release(struct device *dev)
1476 {
1477 struct tpm_chip *chip = dev_get_drvdata(dev);
1478
1479 if (!chip)
1480 return;
1481
1482 tpm_dev_vendor_release(chip);
1483
1484 chip->release(dev);
1485 kfree(chip);
1486 }
1487 EXPORT_SYMBOL_GPL(tpm_dev_release);
1488
1489 /*
1490 * Called from tpm_<specific>.c probe function only for devices
1491 * the driver has determined it should claim. Prior to calling
1492 * this function the specific probe function has called pci_enable_device
1493 * upon errant exit from this function specific probe function should call
1494 * pci_disable_device
1495 */
1496 struct tpm_chip *tpm_register_hardware(struct device *dev,
1497 const struct tpm_vendor_specific *entry)
1498 {
1499 #define DEVNAME_SIZE 7
1500
1501 char *devname;
1502 struct tpm_chip *chip;
1503
1504 /* Driver specific per-device data */
1505 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1506 devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1507
1508 if (chip == NULL || devname == NULL)
1509 goto out_free;
1510
1511 mutex_init(&chip->buffer_mutex);
1512 mutex_init(&chip->tpm_mutex);
1513 INIT_LIST_HEAD(&chip->list);
1514
1515 INIT_WORK(&chip->work, timeout_work);
1516
1517 setup_timer(&chip->user_read_timer, user_reader_timeout,
1518 (unsigned long)chip);
1519
1520 memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1521
1522 chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1523
1524 if (chip->dev_num >= TPM_NUM_DEVICES) {
1525 dev_err(dev, "No available tpm device numbers\n");
1526 goto out_free;
1527 } else if (chip->dev_num == 0)
1528 chip->vendor.miscdev.minor = TPM_MINOR;
1529 else
1530 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1531
1532 set_bit(chip->dev_num, dev_mask);
1533
1534 scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1535 chip->vendor.miscdev.name = devname;
1536
1537 chip->vendor.miscdev.parent = dev;
1538 chip->dev = get_device(dev);
1539 chip->release = dev->release;
1540 dev->release = tpm_dev_release;
1541 dev_set_drvdata(dev, chip);
1542
1543 if (misc_register(&chip->vendor.miscdev)) {
1544 dev_err(chip->dev,
1545 "unable to misc_register %s, minor %d\n",
1546 chip->vendor.miscdev.name,
1547 chip->vendor.miscdev.minor);
1548 goto put_device;
1549 }
1550
1551 if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1552 misc_deregister(&chip->vendor.miscdev);
1553 goto put_device;
1554 }
1555
1556 if (tpm_add_ppi(&dev->kobj)) {
1557 misc_deregister(&chip->vendor.miscdev);
1558 goto put_device;
1559 }
1560
1561 chip->bios_dir = tpm_bios_log_setup(devname);
1562
1563 /* Make chip available */
1564 spin_lock(&driver_lock);
1565 list_add_rcu(&chip->list, &tpm_chip_list);
1566 spin_unlock(&driver_lock);
1567
1568 return chip;
1569
1570 put_device:
1571 put_device(chip->dev);
1572 out_free:
1573 kfree(chip);
1574 kfree(devname);
1575 return NULL;
1576 }
1577 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1578
1579 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1580 MODULE_DESCRIPTION("TPM Driver");
1581 MODULE_VERSION("2.0");
1582 MODULE_LICENSE("GPL");