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
34 enum tpm_const {
35 TPM_MINOR = 224, /* officially assigned */
36 TPM_BUFSIZE = 4096,
37 TPM_NUM_DEVICES = 256,
38 };
39
40 enum tpm_duration {
41 TPM_SHORT = 0,
42 TPM_MEDIUM = 1,
43 TPM_LONG = 2,
44 TPM_UNDEFINED,
45 };
46
47 #define TPM_MAX_ORDINAL 243
48 #define TPM_MAX_PROTECTED_ORDINAL 12
49 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
50
51 /*
52 * Bug workaround - some TPM's don't flush the most
53 * recently changed pcr on suspend, so force the flush
54 * with an extend to the selected _unused_ non-volatile pcr.
55 */
56 static int tpm_suspend_pcr;
57 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
58 MODULE_PARM_DESC(suspend_pcr,
59 "PCR to use for dummy writes to faciltate flush on suspend.");
60
61 static LIST_HEAD(tpm_chip_list);
62 static DEFINE_SPINLOCK(driver_lock);
63 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
64
65 /*
66 * Array with one entry per ordinal defining the maximum amount
67 * of time the chip could take to return the result. The ordinal
68 * designation of short, medium or long is defined in a table in
69 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
70 * values of the SHORT, MEDIUM, and LONG durations are retrieved
71 * from the chip during initialization with a call to tpm_get_timeouts.
72 */
73 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
74 TPM_UNDEFINED, /* 0 */
75 TPM_UNDEFINED,
76 TPM_UNDEFINED,
77 TPM_UNDEFINED,
78 TPM_UNDEFINED,
79 TPM_UNDEFINED, /* 5 */
80 TPM_UNDEFINED,
81 TPM_UNDEFINED,
82 TPM_UNDEFINED,
83 TPM_UNDEFINED,
84 TPM_SHORT, /* 10 */
85 TPM_SHORT,
86 };
87
88 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
89 TPM_UNDEFINED, /* 0 */
90 TPM_UNDEFINED,
91 TPM_UNDEFINED,
92 TPM_UNDEFINED,
93 TPM_UNDEFINED,
94 TPM_UNDEFINED, /* 5 */
95 TPM_UNDEFINED,
96 TPM_UNDEFINED,
97 TPM_UNDEFINED,
98 TPM_UNDEFINED,
99 TPM_SHORT, /* 10 */
100 TPM_SHORT,
101 TPM_MEDIUM,
102 TPM_LONG,
103 TPM_LONG,
104 TPM_MEDIUM, /* 15 */
105 TPM_SHORT,
106 TPM_SHORT,
107 TPM_MEDIUM,
108 TPM_LONG,
109 TPM_SHORT, /* 20 */
110 TPM_SHORT,
111 TPM_MEDIUM,
112 TPM_MEDIUM,
113 TPM_MEDIUM,
114 TPM_SHORT, /* 25 */
115 TPM_SHORT,
116 TPM_MEDIUM,
117 TPM_SHORT,
118 TPM_SHORT,
119 TPM_MEDIUM, /* 30 */
120 TPM_LONG,
121 TPM_MEDIUM,
122 TPM_SHORT,
123 TPM_SHORT,
124 TPM_SHORT, /* 35 */
125 TPM_MEDIUM,
126 TPM_MEDIUM,
127 TPM_UNDEFINED,
128 TPM_UNDEFINED,
129 TPM_MEDIUM, /* 40 */
130 TPM_LONG,
131 TPM_MEDIUM,
132 TPM_SHORT,
133 TPM_SHORT,
134 TPM_SHORT, /* 45 */
135 TPM_SHORT,
136 TPM_SHORT,
137 TPM_SHORT,
138 TPM_LONG,
139 TPM_MEDIUM, /* 50 */
140 TPM_MEDIUM,
141 TPM_UNDEFINED,
142 TPM_UNDEFINED,
143 TPM_UNDEFINED,
144 TPM_UNDEFINED, /* 55 */
145 TPM_UNDEFINED,
146 TPM_UNDEFINED,
147 TPM_UNDEFINED,
148 TPM_UNDEFINED,
149 TPM_MEDIUM, /* 60 */
150 TPM_MEDIUM,
151 TPM_MEDIUM,
152 TPM_SHORT,
153 TPM_SHORT,
154 TPM_MEDIUM, /* 65 */
155 TPM_UNDEFINED,
156 TPM_UNDEFINED,
157 TPM_UNDEFINED,
158 TPM_UNDEFINED,
159 TPM_SHORT, /* 70 */
160 TPM_SHORT,
161 TPM_UNDEFINED,
162 TPM_UNDEFINED,
163 TPM_UNDEFINED,
164 TPM_UNDEFINED, /* 75 */
165 TPM_UNDEFINED,
166 TPM_UNDEFINED,
167 TPM_UNDEFINED,
168 TPM_UNDEFINED,
169 TPM_LONG, /* 80 */
170 TPM_UNDEFINED,
171 TPM_MEDIUM,
172 TPM_LONG,
173 TPM_SHORT,
174 TPM_UNDEFINED, /* 85 */
175 TPM_UNDEFINED,
176 TPM_UNDEFINED,
177 TPM_UNDEFINED,
178 TPM_UNDEFINED,
179 TPM_SHORT, /* 90 */
180 TPM_SHORT,
181 TPM_SHORT,
182 TPM_SHORT,
183 TPM_SHORT,
184 TPM_UNDEFINED, /* 95 */
185 TPM_UNDEFINED,
186 TPM_UNDEFINED,
187 TPM_UNDEFINED,
188 TPM_UNDEFINED,
189 TPM_MEDIUM, /* 100 */
190 TPM_SHORT,
191 TPM_SHORT,
192 TPM_UNDEFINED,
193 TPM_UNDEFINED,
194 TPM_UNDEFINED, /* 105 */
195 TPM_UNDEFINED,
196 TPM_UNDEFINED,
197 TPM_UNDEFINED,
198 TPM_UNDEFINED,
199 TPM_SHORT, /* 110 */
200 TPM_SHORT,
201 TPM_SHORT,
202 TPM_SHORT,
203 TPM_SHORT,
204 TPM_SHORT, /* 115 */
205 TPM_SHORT,
206 TPM_SHORT,
207 TPM_UNDEFINED,
208 TPM_UNDEFINED,
209 TPM_LONG, /* 120 */
210 TPM_LONG,
211 TPM_MEDIUM,
212 TPM_UNDEFINED,
213 TPM_SHORT,
214 TPM_SHORT, /* 125 */
215 TPM_SHORT,
216 TPM_LONG,
217 TPM_SHORT,
218 TPM_SHORT,
219 TPM_SHORT, /* 130 */
220 TPM_MEDIUM,
221 TPM_UNDEFINED,
222 TPM_SHORT,
223 TPM_MEDIUM,
224 TPM_UNDEFINED, /* 135 */
225 TPM_UNDEFINED,
226 TPM_UNDEFINED,
227 TPM_UNDEFINED,
228 TPM_UNDEFINED,
229 TPM_SHORT, /* 140 */
230 TPM_SHORT,
231 TPM_UNDEFINED,
232 TPM_UNDEFINED,
233 TPM_UNDEFINED,
234 TPM_UNDEFINED, /* 145 */
235 TPM_UNDEFINED,
236 TPM_UNDEFINED,
237 TPM_UNDEFINED,
238 TPM_UNDEFINED,
239 TPM_SHORT, /* 150 */
240 TPM_MEDIUM,
241 TPM_MEDIUM,
242 TPM_SHORT,
243 TPM_SHORT,
244 TPM_UNDEFINED, /* 155 */
245 TPM_UNDEFINED,
246 TPM_UNDEFINED,
247 TPM_UNDEFINED,
248 TPM_UNDEFINED,
249 TPM_SHORT, /* 160 */
250 TPM_SHORT,
251 TPM_SHORT,
252 TPM_SHORT,
253 TPM_UNDEFINED,
254 TPM_UNDEFINED, /* 165 */
255 TPM_UNDEFINED,
256 TPM_UNDEFINED,
257 TPM_UNDEFINED,
258 TPM_UNDEFINED,
259 TPM_LONG, /* 170 */
260 TPM_UNDEFINED,
261 TPM_UNDEFINED,
262 TPM_UNDEFINED,
263 TPM_UNDEFINED,
264 TPM_UNDEFINED, /* 175 */
265 TPM_UNDEFINED,
266 TPM_UNDEFINED,
267 TPM_UNDEFINED,
268 TPM_UNDEFINED,
269 TPM_MEDIUM, /* 180 */
270 TPM_SHORT,
271 TPM_MEDIUM,
272 TPM_MEDIUM,
273 TPM_MEDIUM,
274 TPM_MEDIUM, /* 185 */
275 TPM_SHORT,
276 TPM_UNDEFINED,
277 TPM_UNDEFINED,
278 TPM_UNDEFINED,
279 TPM_UNDEFINED, /* 190 */
280 TPM_UNDEFINED,
281 TPM_UNDEFINED,
282 TPM_UNDEFINED,
283 TPM_UNDEFINED,
284 TPM_UNDEFINED, /* 195 */
285 TPM_UNDEFINED,
286 TPM_UNDEFINED,
287 TPM_UNDEFINED,
288 TPM_UNDEFINED,
289 TPM_SHORT, /* 200 */
290 TPM_UNDEFINED,
291 TPM_UNDEFINED,
292 TPM_UNDEFINED,
293 TPM_SHORT,
294 TPM_SHORT, /* 205 */
295 TPM_SHORT,
296 TPM_SHORT,
297 TPM_SHORT,
298 TPM_SHORT,
299 TPM_MEDIUM, /* 210 */
300 TPM_UNDEFINED,
301 TPM_MEDIUM,
302 TPM_MEDIUM,
303 TPM_MEDIUM,
304 TPM_UNDEFINED, /* 215 */
305 TPM_MEDIUM,
306 TPM_UNDEFINED,
307 TPM_UNDEFINED,
308 TPM_SHORT,
309 TPM_SHORT, /* 220 */
310 TPM_SHORT,
311 TPM_SHORT,
312 TPM_SHORT,
313 TPM_SHORT,
314 TPM_UNDEFINED, /* 225 */
315 TPM_UNDEFINED,
316 TPM_UNDEFINED,
317 TPM_UNDEFINED,
318 TPM_UNDEFINED,
319 TPM_SHORT, /* 230 */
320 TPM_LONG,
321 TPM_MEDIUM,
322 TPM_UNDEFINED,
323 TPM_UNDEFINED,
324 TPM_UNDEFINED, /* 235 */
325 TPM_UNDEFINED,
326 TPM_UNDEFINED,
327 TPM_UNDEFINED,
328 TPM_UNDEFINED,
329 TPM_SHORT, /* 240 */
330 TPM_UNDEFINED,
331 TPM_MEDIUM,
332 };
333
user_reader_timeout(unsigned long ptr)334 static void user_reader_timeout(unsigned long ptr)
335 {
336 struct tpm_chip *chip = (struct tpm_chip *) ptr;
337
338 schedule_work(&chip->work);
339 }
340
timeout_work(struct work_struct * work)341 static void timeout_work(struct work_struct *work)
342 {
343 struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
344
345 mutex_lock(&chip->buffer_mutex);
346 atomic_set(&chip->data_pending, 0);
347 memset(chip->data_buffer, 0, TPM_BUFSIZE);
348 mutex_unlock(&chip->buffer_mutex);
349 }
350
351 /*
352 * Returns max number of jiffies to wait
353 */
tpm_calc_ordinal_duration(struct tpm_chip * chip,u32 ordinal)354 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
355 u32 ordinal)
356 {
357 int duration_idx = TPM_UNDEFINED;
358 int duration = 0;
359
360 if (ordinal < TPM_MAX_ORDINAL)
361 duration_idx = tpm_ordinal_duration[ordinal];
362 else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
363 TPM_MAX_PROTECTED_ORDINAL)
364 duration_idx =
365 tpm_protected_ordinal_duration[ordinal &
366 TPM_PROTECTED_ORDINAL_MASK];
367
368 if (duration_idx != TPM_UNDEFINED)
369 duration = chip->vendor.duration[duration_idx];
370 if (duration <= 0)
371 return 2 * 60 * HZ;
372 else
373 return duration;
374 }
375 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
376
377 /*
378 * Internal kernel interface to transmit TPM commands
379 */
tpm_transmit(struct tpm_chip * chip,const char * buf,size_t bufsiz)380 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
381 size_t bufsiz)
382 {
383 ssize_t rc;
384 u32 count, ordinal;
385 unsigned long stop;
386
387 if (bufsiz > TPM_BUFSIZE)
388 bufsiz = TPM_BUFSIZE;
389
390 count = be32_to_cpu(*((__be32 *) (buf + 2)));
391 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
392 if (count == 0)
393 return -ENODATA;
394 if (count > bufsiz) {
395 dev_err(chip->dev,
396 "invalid count value %x %zx \n", count, bufsiz);
397 return -E2BIG;
398 }
399
400 mutex_lock(&chip->tpm_mutex);
401
402 if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
403 dev_err(chip->dev,
404 "tpm_transmit: tpm_send: error %zd\n", rc);
405 goto out;
406 }
407
408 if (chip->vendor.irq)
409 goto out_recv;
410
411 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
412 do {
413 u8 status = chip->vendor.status(chip);
414 if ((status & chip->vendor.req_complete_mask) ==
415 chip->vendor.req_complete_val)
416 goto out_recv;
417
418 if ((status == chip->vendor.req_canceled)) {
419 dev_err(chip->dev, "Operation Canceled\n");
420 rc = -ECANCELED;
421 goto out;
422 }
423
424 msleep(TPM_TIMEOUT); /* CHECK */
425 rmb();
426 } while (time_before(jiffies, stop));
427
428 chip->vendor.cancel(chip);
429 dev_err(chip->dev, "Operation Timed out\n");
430 rc = -ETIME;
431 goto out;
432
433 out_recv:
434 rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
435 if (rc < 0)
436 dev_err(chip->dev,
437 "tpm_transmit: tpm_recv: error %zd\n", rc);
438 out:
439 mutex_unlock(&chip->tpm_mutex);
440 return rc;
441 }
442
443 #define TPM_DIGEST_SIZE 20
444 #define TPM_RET_CODE_IDX 6
445
446 enum tpm_capabilities {
447 TPM_CAP_FLAG = cpu_to_be32(4),
448 TPM_CAP_PROP = cpu_to_be32(5),
449 CAP_VERSION_1_1 = cpu_to_be32(0x06),
450 CAP_VERSION_1_2 = cpu_to_be32(0x1A)
451 };
452
453 enum tpm_sub_capabilities {
454 TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
455 TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
456 TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
457 TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
458 TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
459 TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
460 TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
461
462 };
463
transmit_cmd(struct tpm_chip * chip,struct tpm_cmd_t * cmd,int len,const char * desc)464 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
465 int len, const char *desc)
466 {
467 int err;
468
469 len = tpm_transmit(chip,(u8 *) cmd, len);
470 if (len < 0)
471 return len;
472 else if (len < TPM_HEADER_SIZE)
473 return -EFAULT;
474
475 err = be32_to_cpu(cmd->header.out.return_code);
476 if (err != 0)
477 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
478
479 return err;
480 }
481
482 #define TPM_INTERNAL_RESULT_SIZE 200
483 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
484 #define TPM_ORD_GET_CAP cpu_to_be32(101)
485
486 static const struct tpm_input_header tpm_getcap_header = {
487 .tag = TPM_TAG_RQU_COMMAND,
488 .length = cpu_to_be32(22),
489 .ordinal = TPM_ORD_GET_CAP
490 };
491
tpm_getcap(struct device * dev,__be32 subcap_id,cap_t * cap,const char * desc)492 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
493 const char *desc)
494 {
495 struct tpm_cmd_t tpm_cmd;
496 int rc;
497 struct tpm_chip *chip = dev_get_drvdata(dev);
498
499 tpm_cmd.header.in = tpm_getcap_header;
500 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
501 tpm_cmd.params.getcap_in.cap = subcap_id;
502 /*subcap field not necessary */
503 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
504 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
505 } else {
506 if (subcap_id == TPM_CAP_FLAG_PERM ||
507 subcap_id == TPM_CAP_FLAG_VOL)
508 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
509 else
510 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
511 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
512 tpm_cmd.params.getcap_in.subcap = subcap_id;
513 }
514 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
515 if (!rc)
516 *cap = tpm_cmd.params.getcap_out.cap;
517 return rc;
518 }
519
tpm_gen_interrupt(struct tpm_chip * chip)520 void tpm_gen_interrupt(struct tpm_chip *chip)
521 {
522 struct tpm_cmd_t tpm_cmd;
523 ssize_t rc;
524
525 tpm_cmd.header.in = tpm_getcap_header;
526 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
527 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
528 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
529
530 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
531 "attempting to determine the timeouts");
532 }
533 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
534
tpm_get_timeouts(struct tpm_chip * chip)535 int tpm_get_timeouts(struct tpm_chip *chip)
536 {
537 struct tpm_cmd_t tpm_cmd;
538 struct timeout_t *timeout_cap;
539 struct duration_t *duration_cap;
540 ssize_t rc;
541 u32 timeout;
542 unsigned int scale = 1;
543
544 tpm_cmd.header.in = tpm_getcap_header;
545 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
546 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
547 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
548
549 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
550 "attempting to determine the timeouts");
551 if (rc)
552 goto duration;
553
554 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
555 be32_to_cpu(tpm_cmd.header.out.length)
556 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
557 return -EINVAL;
558
559 timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
560 /* Don't overwrite default if value is 0 */
561 timeout = be32_to_cpu(timeout_cap->a);
562 if (timeout && timeout < 1000) {
563 /* timeouts in msec rather usec */
564 scale = 1000;
565 chip->vendor.timeout_adjusted = true;
566 }
567 if (timeout)
568 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
569 timeout = be32_to_cpu(timeout_cap->b);
570 if (timeout)
571 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
572 timeout = be32_to_cpu(timeout_cap->c);
573 if (timeout)
574 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
575 timeout = be32_to_cpu(timeout_cap->d);
576 if (timeout)
577 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
578
579 duration:
580 tpm_cmd.header.in = tpm_getcap_header;
581 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
582 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
583 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
584
585 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
586 "attempting to determine the durations");
587 if (rc)
588 return rc;
589
590 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
591 be32_to_cpu(tpm_cmd.header.out.length)
592 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
593 return -EINVAL;
594
595 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
596 chip->vendor.duration[TPM_SHORT] =
597 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
598 chip->vendor.duration[TPM_MEDIUM] =
599 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
600 chip->vendor.duration[TPM_LONG] =
601 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
602
603 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
604 * value wrong and apparently reports msecs rather than usecs. So we
605 * fix up the resulting too-small TPM_SHORT value to make things work.
606 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
607 */
608 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
609 chip->vendor.duration[TPM_SHORT] = HZ;
610 chip->vendor.duration[TPM_MEDIUM] *= 1000;
611 chip->vendor.duration[TPM_LONG] *= 1000;
612 chip->vendor.duration_adjusted = true;
613 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
614 }
615 return 0;
616 }
617 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
618
619 #define TPM_ORD_CONTINUE_SELFTEST 83
620 #define CONTINUE_SELFTEST_RESULT_SIZE 10
621
622 static struct tpm_input_header continue_selftest_header = {
623 .tag = TPM_TAG_RQU_COMMAND,
624 .length = cpu_to_be32(10),
625 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
626 };
627
628 /**
629 * tpm_continue_selftest -- run TPM's selftest
630 * @chip: TPM chip to use
631 *
632 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
633 * a TPM error code.
634 */
tpm_continue_selftest(struct tpm_chip * chip)635 static int tpm_continue_selftest(struct tpm_chip *chip)
636 {
637 int rc;
638 struct tpm_cmd_t cmd;
639
640 cmd.header.in = continue_selftest_header;
641 rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
642 "continue selftest");
643 return rc;
644 }
645
tpm_show_enabled(struct device * dev,struct device_attribute * attr,char * buf)646 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
647 char *buf)
648 {
649 cap_t cap;
650 ssize_t rc;
651
652 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
653 "attempting to determine the permanent enabled state");
654 if (rc)
655 return 0;
656
657 rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
658 return rc;
659 }
660 EXPORT_SYMBOL_GPL(tpm_show_enabled);
661
tpm_show_active(struct device * dev,struct device_attribute * attr,char * buf)662 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
663 char *buf)
664 {
665 cap_t cap;
666 ssize_t rc;
667
668 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
669 "attempting to determine the permanent active state");
670 if (rc)
671 return 0;
672
673 rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
674 return rc;
675 }
676 EXPORT_SYMBOL_GPL(tpm_show_active);
677
tpm_show_owned(struct device * dev,struct device_attribute * attr,char * buf)678 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
679 char *buf)
680 {
681 cap_t cap;
682 ssize_t rc;
683
684 rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
685 "attempting to determine the owner state");
686 if (rc)
687 return 0;
688
689 rc = sprintf(buf, "%d\n", cap.owned);
690 return rc;
691 }
692 EXPORT_SYMBOL_GPL(tpm_show_owned);
693
tpm_show_temp_deactivated(struct device * dev,struct device_attribute * attr,char * buf)694 ssize_t tpm_show_temp_deactivated(struct device * dev,
695 struct device_attribute * attr, char *buf)
696 {
697 cap_t cap;
698 ssize_t rc;
699
700 rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
701 "attempting to determine the temporary state");
702 if (rc)
703 return 0;
704
705 rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
706 return rc;
707 }
708 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
709
710 /*
711 * tpm_chip_find_get - return tpm_chip for given chip number
712 */
tpm_chip_find_get(int chip_num)713 static struct tpm_chip *tpm_chip_find_get(int chip_num)
714 {
715 struct tpm_chip *pos, *chip = NULL;
716
717 rcu_read_lock();
718 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
719 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
720 continue;
721
722 if (try_module_get(pos->dev->driver->owner)) {
723 chip = pos;
724 break;
725 }
726 }
727 rcu_read_unlock();
728 return chip;
729 }
730
731 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
732 #define READ_PCR_RESULT_SIZE 30
733 static struct tpm_input_header pcrread_header = {
734 .tag = TPM_TAG_RQU_COMMAND,
735 .length = cpu_to_be32(14),
736 .ordinal = TPM_ORDINAL_PCRREAD
737 };
738
__tpm_pcr_read(struct tpm_chip * chip,int pcr_idx,u8 * res_buf)739 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
740 {
741 int rc;
742 struct tpm_cmd_t cmd;
743
744 cmd.header.in = pcrread_header;
745 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
746 rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
747 "attempting to read a pcr value");
748
749 if (rc == 0)
750 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
751 TPM_DIGEST_SIZE);
752 return rc;
753 }
754
755 /**
756 * tpm_pcr_read - read a pcr value
757 * @chip_num: tpm idx # or ANY
758 * @pcr_idx: pcr idx to retrieve
759 * @res_buf: TPM_PCR value
760 * size of res_buf is 20 bytes (or NULL if you don't care)
761 *
762 * The TPM driver should be built-in, but for whatever reason it
763 * isn't, protect against the chip disappearing, by incrementing
764 * the module usage count.
765 */
tpm_pcr_read(u32 chip_num,int pcr_idx,u8 * res_buf)766 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
767 {
768 struct tpm_chip *chip;
769 int rc;
770
771 chip = tpm_chip_find_get(chip_num);
772 if (chip == NULL)
773 return -ENODEV;
774 rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
775 tpm_chip_put(chip);
776 return rc;
777 }
778 EXPORT_SYMBOL_GPL(tpm_pcr_read);
779
780 /**
781 * tpm_pcr_extend - extend pcr value with hash
782 * @chip_num: tpm idx # or AN&
783 * @pcr_idx: pcr idx to extend
784 * @hash: hash value used to extend pcr value
785 *
786 * The TPM driver should be built-in, but for whatever reason it
787 * isn't, protect against the chip disappearing, by incrementing
788 * the module usage count.
789 */
790 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
791 #define EXTEND_PCR_RESULT_SIZE 34
792 static struct tpm_input_header pcrextend_header = {
793 .tag = TPM_TAG_RQU_COMMAND,
794 .length = cpu_to_be32(34),
795 .ordinal = TPM_ORD_PCR_EXTEND
796 };
797
tpm_pcr_extend(u32 chip_num,int pcr_idx,const u8 * hash)798 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
799 {
800 struct tpm_cmd_t cmd;
801 int rc;
802 struct tpm_chip *chip;
803
804 chip = tpm_chip_find_get(chip_num);
805 if (chip == NULL)
806 return -ENODEV;
807
808 cmd.header.in = pcrextend_header;
809 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
810 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
811 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
812 "attempting extend a PCR value");
813
814 tpm_chip_put(chip);
815 return rc;
816 }
817 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
818
819 /**
820 * tpm_do_selftest - have the TPM continue its selftest and wait until it
821 * can receive further commands
822 * @chip: TPM chip to use
823 *
824 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
825 * a TPM error code.
826 */
tpm_do_selftest(struct tpm_chip * chip)827 int tpm_do_selftest(struct tpm_chip *chip)
828 {
829 int rc;
830 unsigned int loops;
831 unsigned int delay_msec = 1000;
832 unsigned long duration;
833 struct tpm_cmd_t cmd;
834
835 duration = tpm_calc_ordinal_duration(chip,
836 TPM_ORD_CONTINUE_SELFTEST);
837
838 loops = jiffies_to_msecs(duration) / delay_msec;
839
840 rc = tpm_continue_selftest(chip);
841 /* This may fail if there was no TPM driver during a suspend/resume
842 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
843 */
844 if (rc)
845 return rc;
846
847 do {
848 /* Attempt to read a PCR value */
849 cmd.header.in = pcrread_header;
850 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
851 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
852
853 if (rc < TPM_HEADER_SIZE)
854 return -EFAULT;
855
856 rc = be32_to_cpu(cmd.header.out.return_code);
857 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
858 dev_info(chip->dev,
859 "TPM is disabled/deactivated (0x%X)\n", rc);
860 /* TPM is disabled and/or deactivated; driver can
861 * proceed and TPM does handle commands for
862 * suspend/resume correctly
863 */
864 return 0;
865 }
866 if (rc != TPM_WARN_DOING_SELFTEST)
867 return rc;
868 msleep(delay_msec);
869 } while (--loops > 0);
870
871 return rc;
872 }
873 EXPORT_SYMBOL_GPL(tpm_do_selftest);
874
tpm_send(u32 chip_num,void * cmd,size_t buflen)875 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
876 {
877 struct tpm_chip *chip;
878 int rc;
879
880 chip = tpm_chip_find_get(chip_num);
881 if (chip == NULL)
882 return -ENODEV;
883
884 rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
885
886 tpm_chip_put(chip);
887 return rc;
888 }
889 EXPORT_SYMBOL_GPL(tpm_send);
890
tpm_show_pcrs(struct device * dev,struct device_attribute * attr,char * buf)891 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
892 char *buf)
893 {
894 cap_t cap;
895 u8 digest[TPM_DIGEST_SIZE];
896 ssize_t rc;
897 int i, j, num_pcrs;
898 char *str = buf;
899 struct tpm_chip *chip = dev_get_drvdata(dev);
900
901 rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
902 "attempting to determine the number of PCRS");
903 if (rc)
904 return 0;
905
906 num_pcrs = be32_to_cpu(cap.num_pcrs);
907 for (i = 0; i < num_pcrs; i++) {
908 rc = __tpm_pcr_read(chip, i, digest);
909 if (rc)
910 break;
911 str += sprintf(str, "PCR-%02d: ", i);
912 for (j = 0; j < TPM_DIGEST_SIZE; j++)
913 str += sprintf(str, "%02X ", digest[j]);
914 str += sprintf(str, "\n");
915 }
916 return str - buf;
917 }
918 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
919
920 #define READ_PUBEK_RESULT_SIZE 314
921 #define TPM_ORD_READPUBEK cpu_to_be32(124)
922 struct tpm_input_header tpm_readpubek_header = {
923 .tag = TPM_TAG_RQU_COMMAND,
924 .length = cpu_to_be32(30),
925 .ordinal = TPM_ORD_READPUBEK
926 };
927
tpm_show_pubek(struct device * dev,struct device_attribute * attr,char * buf)928 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
929 char *buf)
930 {
931 u8 *data;
932 struct tpm_cmd_t tpm_cmd;
933 ssize_t err;
934 int i, rc;
935 char *str = buf;
936
937 struct tpm_chip *chip = dev_get_drvdata(dev);
938
939 tpm_cmd.header.in = tpm_readpubek_header;
940 err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
941 "attempting to read the PUBEK");
942 if (err)
943 goto out;
944
945 /*
946 ignore header 10 bytes
947 algorithm 32 bits (1 == RSA )
948 encscheme 16 bits
949 sigscheme 16 bits
950 parameters (RSA 12->bytes: keybit, #primes, expbit)
951 keylenbytes 32 bits
952 256 byte modulus
953 ignore checksum 20 bytes
954 */
955 data = tpm_cmd.params.readpubek_out_buffer;
956 str +=
957 sprintf(str,
958 "Algorithm: %02X %02X %02X %02X\n"
959 "Encscheme: %02X %02X\n"
960 "Sigscheme: %02X %02X\n"
961 "Parameters: %02X %02X %02X %02X "
962 "%02X %02X %02X %02X "
963 "%02X %02X %02X %02X\n"
964 "Modulus length: %d\n"
965 "Modulus:\n",
966 data[0], data[1], data[2], data[3],
967 data[4], data[5],
968 data[6], data[7],
969 data[12], data[13], data[14], data[15],
970 data[16], data[17], data[18], data[19],
971 data[20], data[21], data[22], data[23],
972 be32_to_cpu(*((__be32 *) (data + 24))));
973
974 for (i = 0; i < 256; i++) {
975 str += sprintf(str, "%02X ", data[i + 28]);
976 if ((i + 1) % 16 == 0)
977 str += sprintf(str, "\n");
978 }
979 out:
980 rc = str - buf;
981 return rc;
982 }
983 EXPORT_SYMBOL_GPL(tpm_show_pubek);
984
985
tpm_show_caps(struct device * dev,struct device_attribute * attr,char * buf)986 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
987 char *buf)
988 {
989 cap_t cap;
990 ssize_t rc;
991 char *str = buf;
992
993 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
994 "attempting to determine the manufacturer");
995 if (rc)
996 return 0;
997 str += sprintf(str, "Manufacturer: 0x%x\n",
998 be32_to_cpu(cap.manufacturer_id));
999
1000 rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1001 "attempting to determine the 1.1 version");
1002 if (rc)
1003 return 0;
1004 str += sprintf(str,
1005 "TCG version: %d.%d\nFirmware version: %d.%d\n",
1006 cap.tpm_version.Major, cap.tpm_version.Minor,
1007 cap.tpm_version.revMajor, cap.tpm_version.revMinor);
1008 return str - buf;
1009 }
1010 EXPORT_SYMBOL_GPL(tpm_show_caps);
1011
tpm_show_caps_1_2(struct device * dev,struct device_attribute * attr,char * buf)1012 ssize_t tpm_show_caps_1_2(struct device * dev,
1013 struct device_attribute * attr, char *buf)
1014 {
1015 cap_t cap;
1016 ssize_t rc;
1017 char *str = buf;
1018
1019 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1020 "attempting to determine the manufacturer");
1021 if (rc)
1022 return 0;
1023 str += sprintf(str, "Manufacturer: 0x%x\n",
1024 be32_to_cpu(cap.manufacturer_id));
1025 rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1026 "attempting to determine the 1.2 version");
1027 if (rc)
1028 return 0;
1029 str += sprintf(str,
1030 "TCG version: %d.%d\nFirmware version: %d.%d\n",
1031 cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
1032 cap.tpm_version_1_2.revMajor,
1033 cap.tpm_version_1_2.revMinor);
1034 return str - buf;
1035 }
1036 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
1037
tpm_show_durations(struct device * dev,struct device_attribute * attr,char * buf)1038 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1039 char *buf)
1040 {
1041 struct tpm_chip *chip = dev_get_drvdata(dev);
1042
1043 if (chip->vendor.duration[TPM_LONG] == 0)
1044 return 0;
1045
1046 return sprintf(buf, "%d %d %d [%s]\n",
1047 jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1048 jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1049 jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1050 chip->vendor.duration_adjusted
1051 ? "adjusted" : "original");
1052 }
1053 EXPORT_SYMBOL_GPL(tpm_show_durations);
1054
tpm_show_timeouts(struct device * dev,struct device_attribute * attr,char * buf)1055 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1056 char *buf)
1057 {
1058 struct tpm_chip *chip = dev_get_drvdata(dev);
1059
1060 return sprintf(buf, "%d %d %d %d [%s]\n",
1061 jiffies_to_usecs(chip->vendor.timeout_a),
1062 jiffies_to_usecs(chip->vendor.timeout_b),
1063 jiffies_to_usecs(chip->vendor.timeout_c),
1064 jiffies_to_usecs(chip->vendor.timeout_d),
1065 chip->vendor.timeout_adjusted
1066 ? "adjusted" : "original");
1067 }
1068 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1069
tpm_store_cancel(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)1070 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1071 const char *buf, size_t count)
1072 {
1073 struct tpm_chip *chip = dev_get_drvdata(dev);
1074 if (chip == NULL)
1075 return 0;
1076
1077 chip->vendor.cancel(chip);
1078 return count;
1079 }
1080 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1081
wait_for_tpm_stat(struct tpm_chip * chip,u8 mask,unsigned long timeout,wait_queue_head_t * queue)1082 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1083 wait_queue_head_t *queue)
1084 {
1085 unsigned long stop;
1086 long rc;
1087 u8 status;
1088
1089 /* check current status */
1090 status = chip->vendor.status(chip);
1091 if ((status & mask) == mask)
1092 return 0;
1093
1094 stop = jiffies + timeout;
1095
1096 if (chip->vendor.irq) {
1097 again:
1098 timeout = stop - jiffies;
1099 if ((long)timeout <= 0)
1100 return -ETIME;
1101 rc = wait_event_interruptible_timeout(*queue,
1102 ((chip->vendor.status(chip)
1103 & mask) == mask),
1104 timeout);
1105 if (rc > 0)
1106 return 0;
1107 if (rc == -ERESTARTSYS && freezing(current)) {
1108 clear_thread_flag(TIF_SIGPENDING);
1109 goto again;
1110 }
1111 } else {
1112 do {
1113 msleep(TPM_TIMEOUT);
1114 status = chip->vendor.status(chip);
1115 if ((status & mask) == mask)
1116 return 0;
1117 } while (time_before(jiffies, stop));
1118 }
1119 return -ETIME;
1120 }
1121 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1122 /*
1123 * Device file system interface to the TPM
1124 *
1125 * It's assured that the chip will be opened just once,
1126 * by the check of is_open variable, which is protected
1127 * by driver_lock.
1128 */
tpm_open(struct inode * inode,struct file * file)1129 int tpm_open(struct inode *inode, struct file *file)
1130 {
1131 int minor = iminor(inode);
1132 struct tpm_chip *chip = NULL, *pos;
1133
1134 rcu_read_lock();
1135 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1136 if (pos->vendor.miscdev.minor == minor) {
1137 chip = pos;
1138 get_device(chip->dev);
1139 break;
1140 }
1141 }
1142 rcu_read_unlock();
1143
1144 if (!chip)
1145 return -ENODEV;
1146
1147 if (test_and_set_bit(0, &chip->is_open)) {
1148 dev_dbg(chip->dev, "Another process owns this TPM\n");
1149 put_device(chip->dev);
1150 return -EBUSY;
1151 }
1152
1153 chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1154 if (chip->data_buffer == NULL) {
1155 clear_bit(0, &chip->is_open);
1156 put_device(chip->dev);
1157 return -ENOMEM;
1158 }
1159
1160 atomic_set(&chip->data_pending, 0);
1161
1162 file->private_data = chip;
1163 return 0;
1164 }
1165 EXPORT_SYMBOL_GPL(tpm_open);
1166
1167 /*
1168 * Called on file close
1169 */
tpm_release(struct inode * inode,struct file * file)1170 int tpm_release(struct inode *inode, struct file *file)
1171 {
1172 struct tpm_chip *chip = file->private_data;
1173
1174 del_singleshot_timer_sync(&chip->user_read_timer);
1175 flush_work_sync(&chip->work);
1176 file->private_data = NULL;
1177 atomic_set(&chip->data_pending, 0);
1178 kfree(chip->data_buffer);
1179 clear_bit(0, &chip->is_open);
1180 put_device(chip->dev);
1181 return 0;
1182 }
1183 EXPORT_SYMBOL_GPL(tpm_release);
1184
tpm_write(struct file * file,const char __user * buf,size_t size,loff_t * off)1185 ssize_t tpm_write(struct file *file, const char __user *buf,
1186 size_t size, loff_t *off)
1187 {
1188 struct tpm_chip *chip = file->private_data;
1189 size_t in_size = size;
1190 ssize_t out_size;
1191
1192 /* cannot perform a write until the read has cleared
1193 either via tpm_read or a user_read_timer timeout.
1194 This also prevents splitted buffered writes from blocking here.
1195 */
1196 if (atomic_read(&chip->data_pending) != 0)
1197 return -EBUSY;
1198
1199 if (in_size > TPM_BUFSIZE)
1200 return -E2BIG;
1201
1202 mutex_lock(&chip->buffer_mutex);
1203
1204 if (copy_from_user
1205 (chip->data_buffer, (void __user *) buf, in_size)) {
1206 mutex_unlock(&chip->buffer_mutex);
1207 return -EFAULT;
1208 }
1209
1210 /* atomic tpm command send and result receive */
1211 out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1212 if (out_size < 0) {
1213 mutex_unlock(&chip->buffer_mutex);
1214 return out_size;
1215 }
1216
1217 atomic_set(&chip->data_pending, out_size);
1218 mutex_unlock(&chip->buffer_mutex);
1219
1220 /* Set a timeout by which the reader must come claim the result */
1221 mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1222
1223 return in_size;
1224 }
1225 EXPORT_SYMBOL_GPL(tpm_write);
1226
tpm_read(struct file * file,char __user * buf,size_t size,loff_t * off)1227 ssize_t tpm_read(struct file *file, char __user *buf,
1228 size_t size, loff_t *off)
1229 {
1230 struct tpm_chip *chip = file->private_data;
1231 ssize_t ret_size;
1232 int rc;
1233
1234 del_singleshot_timer_sync(&chip->user_read_timer);
1235 flush_work_sync(&chip->work);
1236 ret_size = atomic_read(&chip->data_pending);
1237 atomic_set(&chip->data_pending, 0);
1238 if (ret_size > 0) { /* relay data */
1239 ssize_t orig_ret_size = ret_size;
1240 if (size < ret_size)
1241 ret_size = size;
1242
1243 mutex_lock(&chip->buffer_mutex);
1244 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1245 memset(chip->data_buffer, 0, orig_ret_size);
1246 if (rc)
1247 ret_size = -EFAULT;
1248
1249 mutex_unlock(&chip->buffer_mutex);
1250 }
1251
1252 return ret_size;
1253 }
1254 EXPORT_SYMBOL_GPL(tpm_read);
1255
tpm_remove_hardware(struct device * dev)1256 void tpm_remove_hardware(struct device *dev)
1257 {
1258 struct tpm_chip *chip = dev_get_drvdata(dev);
1259
1260 if (chip == NULL) {
1261 dev_err(dev, "No device data found\n");
1262 return;
1263 }
1264
1265 spin_lock(&driver_lock);
1266 list_del_rcu(&chip->list);
1267 spin_unlock(&driver_lock);
1268 synchronize_rcu();
1269
1270 misc_deregister(&chip->vendor.miscdev);
1271 sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1272 tpm_bios_log_teardown(chip->bios_dir);
1273
1274 /* write it this way to be explicit (chip->dev == dev) */
1275 put_device(chip->dev);
1276 }
1277 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1278
1279 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1280 #define SAVESTATE_RESULT_SIZE 10
1281
1282 static struct tpm_input_header savestate_header = {
1283 .tag = TPM_TAG_RQU_COMMAND,
1284 .length = cpu_to_be32(10),
1285 .ordinal = TPM_ORD_SAVESTATE
1286 };
1287
1288 /*
1289 * We are about to suspend. Save the TPM state
1290 * so that it can be restored.
1291 */
tpm_pm_suspend(struct device * dev,pm_message_t pm_state)1292 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1293 {
1294 struct tpm_chip *chip = dev_get_drvdata(dev);
1295 struct tpm_cmd_t cmd;
1296 int rc;
1297
1298 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1299
1300 if (chip == NULL)
1301 return -ENODEV;
1302
1303 /* for buggy tpm, flush pcrs with extend to selected dummy */
1304 if (tpm_suspend_pcr) {
1305 cmd.header.in = pcrextend_header;
1306 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1307 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1308 TPM_DIGEST_SIZE);
1309 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1310 "extending dummy pcr before suspend");
1311 }
1312
1313 /* now do the actual savestate */
1314 cmd.header.in = savestate_header;
1315 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1316 "sending savestate before suspend");
1317 return rc;
1318 }
1319 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1320
1321 /*
1322 * Resume from a power safe. The BIOS already restored
1323 * the TPM state.
1324 */
tpm_pm_resume(struct device * dev)1325 int tpm_pm_resume(struct device *dev)
1326 {
1327 struct tpm_chip *chip = dev_get_drvdata(dev);
1328
1329 if (chip == NULL)
1330 return -ENODEV;
1331
1332 return 0;
1333 }
1334 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1335
1336 /* In case vendor provided release function, call it too.*/
1337
tpm_dev_vendor_release(struct tpm_chip * chip)1338 void tpm_dev_vendor_release(struct tpm_chip *chip)
1339 {
1340 if (chip->vendor.release)
1341 chip->vendor.release(chip->dev);
1342
1343 clear_bit(chip->dev_num, dev_mask);
1344 kfree(chip->vendor.miscdev.name);
1345 }
1346 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1347
1348
1349 /*
1350 * Once all references to platform device are down to 0,
1351 * release all allocated structures.
1352 */
tpm_dev_release(struct device * dev)1353 void tpm_dev_release(struct device *dev)
1354 {
1355 struct tpm_chip *chip = dev_get_drvdata(dev);
1356
1357 tpm_dev_vendor_release(chip);
1358
1359 chip->release(dev);
1360 kfree(chip);
1361 }
1362 EXPORT_SYMBOL_GPL(tpm_dev_release);
1363
1364 /*
1365 * Called from tpm_<specific>.c probe function only for devices
1366 * the driver has determined it should claim. Prior to calling
1367 * this function the specific probe function has called pci_enable_device
1368 * upon errant exit from this function specific probe function should call
1369 * pci_disable_device
1370 */
tpm_register_hardware(struct device * dev,const struct tpm_vendor_specific * entry)1371 struct tpm_chip *tpm_register_hardware(struct device *dev,
1372 const struct tpm_vendor_specific *entry)
1373 {
1374 #define DEVNAME_SIZE 7
1375
1376 char *devname;
1377 struct tpm_chip *chip;
1378
1379 /* Driver specific per-device data */
1380 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1381 devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1382
1383 if (chip == NULL || devname == NULL)
1384 goto out_free;
1385
1386 mutex_init(&chip->buffer_mutex);
1387 mutex_init(&chip->tpm_mutex);
1388 INIT_LIST_HEAD(&chip->list);
1389
1390 INIT_WORK(&chip->work, timeout_work);
1391
1392 setup_timer(&chip->user_read_timer, user_reader_timeout,
1393 (unsigned long)chip);
1394
1395 memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1396
1397 chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1398
1399 if (chip->dev_num >= TPM_NUM_DEVICES) {
1400 dev_err(dev, "No available tpm device numbers\n");
1401 goto out_free;
1402 } else if (chip->dev_num == 0)
1403 chip->vendor.miscdev.minor = TPM_MINOR;
1404 else
1405 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1406
1407 set_bit(chip->dev_num, dev_mask);
1408
1409 scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1410 chip->vendor.miscdev.name = devname;
1411
1412 chip->vendor.miscdev.parent = dev;
1413 chip->dev = get_device(dev);
1414 chip->release = dev->release;
1415 dev->release = tpm_dev_release;
1416 dev_set_drvdata(dev, chip);
1417
1418 if (misc_register(&chip->vendor.miscdev)) {
1419 dev_err(chip->dev,
1420 "unable to misc_register %s, minor %d\n",
1421 chip->vendor.miscdev.name,
1422 chip->vendor.miscdev.minor);
1423 put_device(chip->dev);
1424 return NULL;
1425 }
1426
1427 if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1428 misc_deregister(&chip->vendor.miscdev);
1429 put_device(chip->dev);
1430
1431 return NULL;
1432 }
1433
1434 chip->bios_dir = tpm_bios_log_setup(devname);
1435
1436 /* Make chip available */
1437 spin_lock(&driver_lock);
1438 list_add_rcu(&chip->list, &tpm_chip_list);
1439 spin_unlock(&driver_lock);
1440
1441 return chip;
1442
1443 out_free:
1444 kfree(chip);
1445 kfree(devname);
1446 return NULL;
1447 }
1448 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1449
1450 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1451 MODULE_DESCRIPTION("TPM Driver");
1452 MODULE_VERSION("2.0");
1453 MODULE_LICENSE("GPL");
1454