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/mutex.h>
28 #include <linux/spinlock.h>
29 #include <linux/smp_lock.h>
30
31 #include "tpm.h"
32
33 enum tpm_const {
34 TPM_MINOR = 224, /* officially assigned */
35 TPM_BUFSIZE = 2048,
36 TPM_NUM_DEVICES = 256,
37 };
38
39 enum tpm_duration {
40 TPM_SHORT = 0,
41 TPM_MEDIUM = 1,
42 TPM_LONG = 2,
43 TPM_UNDEFINED,
44 };
45
46 #define TPM_MAX_ORDINAL 243
47 #define TPM_MAX_PROTECTED_ORDINAL 12
48 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
49
50 static LIST_HEAD(tpm_chip_list);
51 static DEFINE_SPINLOCK(driver_lock);
52 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
53
54 /*
55 * Array with one entry per ordinal defining the maximum amount
56 * of time the chip could take to return the result. The ordinal
57 * designation of short, medium or long is defined in a table in
58 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
59 * values of the SHORT, MEDIUM, and LONG durations are retrieved
60 * from the chip during initialization with a call to tpm_get_timeouts.
61 */
62 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
63 TPM_UNDEFINED, /* 0 */
64 TPM_UNDEFINED,
65 TPM_UNDEFINED,
66 TPM_UNDEFINED,
67 TPM_UNDEFINED,
68 TPM_UNDEFINED, /* 5 */
69 TPM_UNDEFINED,
70 TPM_UNDEFINED,
71 TPM_UNDEFINED,
72 TPM_UNDEFINED,
73 TPM_SHORT, /* 10 */
74 TPM_SHORT,
75 };
76
77 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
78 TPM_UNDEFINED, /* 0 */
79 TPM_UNDEFINED,
80 TPM_UNDEFINED,
81 TPM_UNDEFINED,
82 TPM_UNDEFINED,
83 TPM_UNDEFINED, /* 5 */
84 TPM_UNDEFINED,
85 TPM_UNDEFINED,
86 TPM_UNDEFINED,
87 TPM_UNDEFINED,
88 TPM_SHORT, /* 10 */
89 TPM_SHORT,
90 TPM_MEDIUM,
91 TPM_LONG,
92 TPM_LONG,
93 TPM_MEDIUM, /* 15 */
94 TPM_SHORT,
95 TPM_SHORT,
96 TPM_MEDIUM,
97 TPM_LONG,
98 TPM_SHORT, /* 20 */
99 TPM_SHORT,
100 TPM_MEDIUM,
101 TPM_MEDIUM,
102 TPM_MEDIUM,
103 TPM_SHORT, /* 25 */
104 TPM_SHORT,
105 TPM_MEDIUM,
106 TPM_SHORT,
107 TPM_SHORT,
108 TPM_MEDIUM, /* 30 */
109 TPM_LONG,
110 TPM_MEDIUM,
111 TPM_SHORT,
112 TPM_SHORT,
113 TPM_SHORT, /* 35 */
114 TPM_MEDIUM,
115 TPM_MEDIUM,
116 TPM_UNDEFINED,
117 TPM_UNDEFINED,
118 TPM_MEDIUM, /* 40 */
119 TPM_LONG,
120 TPM_MEDIUM,
121 TPM_SHORT,
122 TPM_SHORT,
123 TPM_SHORT, /* 45 */
124 TPM_SHORT,
125 TPM_SHORT,
126 TPM_SHORT,
127 TPM_LONG,
128 TPM_MEDIUM, /* 50 */
129 TPM_MEDIUM,
130 TPM_UNDEFINED,
131 TPM_UNDEFINED,
132 TPM_UNDEFINED,
133 TPM_UNDEFINED, /* 55 */
134 TPM_UNDEFINED,
135 TPM_UNDEFINED,
136 TPM_UNDEFINED,
137 TPM_UNDEFINED,
138 TPM_MEDIUM, /* 60 */
139 TPM_MEDIUM,
140 TPM_MEDIUM,
141 TPM_SHORT,
142 TPM_SHORT,
143 TPM_MEDIUM, /* 65 */
144 TPM_UNDEFINED,
145 TPM_UNDEFINED,
146 TPM_UNDEFINED,
147 TPM_UNDEFINED,
148 TPM_SHORT, /* 70 */
149 TPM_SHORT,
150 TPM_UNDEFINED,
151 TPM_UNDEFINED,
152 TPM_UNDEFINED,
153 TPM_UNDEFINED, /* 75 */
154 TPM_UNDEFINED,
155 TPM_UNDEFINED,
156 TPM_UNDEFINED,
157 TPM_UNDEFINED,
158 TPM_LONG, /* 80 */
159 TPM_UNDEFINED,
160 TPM_MEDIUM,
161 TPM_LONG,
162 TPM_SHORT,
163 TPM_UNDEFINED, /* 85 */
164 TPM_UNDEFINED,
165 TPM_UNDEFINED,
166 TPM_UNDEFINED,
167 TPM_UNDEFINED,
168 TPM_SHORT, /* 90 */
169 TPM_SHORT,
170 TPM_SHORT,
171 TPM_SHORT,
172 TPM_SHORT,
173 TPM_UNDEFINED, /* 95 */
174 TPM_UNDEFINED,
175 TPM_UNDEFINED,
176 TPM_UNDEFINED,
177 TPM_UNDEFINED,
178 TPM_MEDIUM, /* 100 */
179 TPM_SHORT,
180 TPM_SHORT,
181 TPM_UNDEFINED,
182 TPM_UNDEFINED,
183 TPM_UNDEFINED, /* 105 */
184 TPM_UNDEFINED,
185 TPM_UNDEFINED,
186 TPM_UNDEFINED,
187 TPM_UNDEFINED,
188 TPM_SHORT, /* 110 */
189 TPM_SHORT,
190 TPM_SHORT,
191 TPM_SHORT,
192 TPM_SHORT,
193 TPM_SHORT, /* 115 */
194 TPM_SHORT,
195 TPM_SHORT,
196 TPM_UNDEFINED,
197 TPM_UNDEFINED,
198 TPM_LONG, /* 120 */
199 TPM_LONG,
200 TPM_MEDIUM,
201 TPM_UNDEFINED,
202 TPM_SHORT,
203 TPM_SHORT, /* 125 */
204 TPM_SHORT,
205 TPM_LONG,
206 TPM_SHORT,
207 TPM_SHORT,
208 TPM_SHORT, /* 130 */
209 TPM_MEDIUM,
210 TPM_UNDEFINED,
211 TPM_SHORT,
212 TPM_MEDIUM,
213 TPM_UNDEFINED, /* 135 */
214 TPM_UNDEFINED,
215 TPM_UNDEFINED,
216 TPM_UNDEFINED,
217 TPM_UNDEFINED,
218 TPM_SHORT, /* 140 */
219 TPM_SHORT,
220 TPM_UNDEFINED,
221 TPM_UNDEFINED,
222 TPM_UNDEFINED,
223 TPM_UNDEFINED, /* 145 */
224 TPM_UNDEFINED,
225 TPM_UNDEFINED,
226 TPM_UNDEFINED,
227 TPM_UNDEFINED,
228 TPM_SHORT, /* 150 */
229 TPM_MEDIUM,
230 TPM_MEDIUM,
231 TPM_SHORT,
232 TPM_SHORT,
233 TPM_UNDEFINED, /* 155 */
234 TPM_UNDEFINED,
235 TPM_UNDEFINED,
236 TPM_UNDEFINED,
237 TPM_UNDEFINED,
238 TPM_SHORT, /* 160 */
239 TPM_SHORT,
240 TPM_SHORT,
241 TPM_SHORT,
242 TPM_UNDEFINED,
243 TPM_UNDEFINED, /* 165 */
244 TPM_UNDEFINED,
245 TPM_UNDEFINED,
246 TPM_UNDEFINED,
247 TPM_UNDEFINED,
248 TPM_LONG, /* 170 */
249 TPM_UNDEFINED,
250 TPM_UNDEFINED,
251 TPM_UNDEFINED,
252 TPM_UNDEFINED,
253 TPM_UNDEFINED, /* 175 */
254 TPM_UNDEFINED,
255 TPM_UNDEFINED,
256 TPM_UNDEFINED,
257 TPM_UNDEFINED,
258 TPM_MEDIUM, /* 180 */
259 TPM_SHORT,
260 TPM_MEDIUM,
261 TPM_MEDIUM,
262 TPM_MEDIUM,
263 TPM_MEDIUM, /* 185 */
264 TPM_SHORT,
265 TPM_UNDEFINED,
266 TPM_UNDEFINED,
267 TPM_UNDEFINED,
268 TPM_UNDEFINED, /* 190 */
269 TPM_UNDEFINED,
270 TPM_UNDEFINED,
271 TPM_UNDEFINED,
272 TPM_UNDEFINED,
273 TPM_UNDEFINED, /* 195 */
274 TPM_UNDEFINED,
275 TPM_UNDEFINED,
276 TPM_UNDEFINED,
277 TPM_UNDEFINED,
278 TPM_SHORT, /* 200 */
279 TPM_UNDEFINED,
280 TPM_UNDEFINED,
281 TPM_UNDEFINED,
282 TPM_SHORT,
283 TPM_SHORT, /* 205 */
284 TPM_SHORT,
285 TPM_SHORT,
286 TPM_SHORT,
287 TPM_SHORT,
288 TPM_MEDIUM, /* 210 */
289 TPM_UNDEFINED,
290 TPM_MEDIUM,
291 TPM_MEDIUM,
292 TPM_MEDIUM,
293 TPM_UNDEFINED, /* 215 */
294 TPM_MEDIUM,
295 TPM_UNDEFINED,
296 TPM_UNDEFINED,
297 TPM_SHORT,
298 TPM_SHORT, /* 220 */
299 TPM_SHORT,
300 TPM_SHORT,
301 TPM_SHORT,
302 TPM_SHORT,
303 TPM_UNDEFINED, /* 225 */
304 TPM_UNDEFINED,
305 TPM_UNDEFINED,
306 TPM_UNDEFINED,
307 TPM_UNDEFINED,
308 TPM_SHORT, /* 230 */
309 TPM_LONG,
310 TPM_MEDIUM,
311 TPM_UNDEFINED,
312 TPM_UNDEFINED,
313 TPM_UNDEFINED, /* 235 */
314 TPM_UNDEFINED,
315 TPM_UNDEFINED,
316 TPM_UNDEFINED,
317 TPM_UNDEFINED,
318 TPM_SHORT, /* 240 */
319 TPM_UNDEFINED,
320 TPM_MEDIUM,
321 };
322
user_reader_timeout(unsigned long ptr)323 static void user_reader_timeout(unsigned long ptr)
324 {
325 struct tpm_chip *chip = (struct tpm_chip *) ptr;
326
327 schedule_work(&chip->work);
328 }
329
timeout_work(struct work_struct * work)330 static void timeout_work(struct work_struct *work)
331 {
332 struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
333
334 mutex_lock(&chip->buffer_mutex);
335 atomic_set(&chip->data_pending, 0);
336 memset(chip->data_buffer, 0, TPM_BUFSIZE);
337 mutex_unlock(&chip->buffer_mutex);
338 }
339
340 /*
341 * Returns max number of jiffies to wait
342 */
tpm_calc_ordinal_duration(struct tpm_chip * chip,u32 ordinal)343 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
344 u32 ordinal)
345 {
346 int duration_idx = TPM_UNDEFINED;
347 int duration = 0;
348
349 if (ordinal < TPM_MAX_ORDINAL)
350 duration_idx = tpm_ordinal_duration[ordinal];
351 else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
352 TPM_MAX_PROTECTED_ORDINAL)
353 duration_idx =
354 tpm_protected_ordinal_duration[ordinal &
355 TPM_PROTECTED_ORDINAL_MASK];
356
357 if (duration_idx != TPM_UNDEFINED)
358 duration = chip->vendor.duration[duration_idx];
359 if (duration <= 0)
360 return 2 * 60 * HZ;
361 else
362 return duration;
363 }
364 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
365
366 /*
367 * Internal kernel interface to transmit TPM commands
368 */
tpm_transmit(struct tpm_chip * chip,const char * buf,size_t bufsiz)369 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
370 size_t bufsiz)
371 {
372 ssize_t rc;
373 u32 count, ordinal;
374 unsigned long stop;
375
376 count = be32_to_cpu(*((__be32 *) (buf + 2)));
377 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
378 if (count == 0)
379 return -ENODATA;
380 if (count > bufsiz) {
381 dev_err(chip->dev,
382 "invalid count value %x %zx \n", count, bufsiz);
383 return -E2BIG;
384 }
385
386 mutex_lock(&chip->tpm_mutex);
387
388 if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
389 dev_err(chip->dev,
390 "tpm_transmit: tpm_send: error %zd\n", rc);
391 goto out;
392 }
393
394 if (chip->vendor.irq)
395 goto out_recv;
396
397 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
398 do {
399 u8 status = chip->vendor.status(chip);
400 if ((status & chip->vendor.req_complete_mask) ==
401 chip->vendor.req_complete_val)
402 goto out_recv;
403
404 if ((status == chip->vendor.req_canceled)) {
405 dev_err(chip->dev, "Operation Canceled\n");
406 rc = -ECANCELED;
407 goto out;
408 }
409
410 msleep(TPM_TIMEOUT); /* CHECK */
411 rmb();
412 } while (time_before(jiffies, stop));
413
414 chip->vendor.cancel(chip);
415 dev_err(chip->dev, "Operation Timed out\n");
416 rc = -ETIME;
417 goto out;
418
419 out_recv:
420 rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
421 if (rc < 0)
422 dev_err(chip->dev,
423 "tpm_transmit: tpm_recv: error %zd\n", rc);
424 out:
425 mutex_unlock(&chip->tpm_mutex);
426 return rc;
427 }
428
429 #define TPM_DIGEST_SIZE 20
430 #define TPM_ERROR_SIZE 10
431 #define TPM_RET_CODE_IDX 6
432 #define TPM_GET_CAP_RET_SIZE_IDX 10
433 #define TPM_GET_CAP_RET_UINT32_1_IDX 14
434 #define TPM_GET_CAP_RET_UINT32_2_IDX 18
435 #define TPM_GET_CAP_RET_UINT32_3_IDX 22
436 #define TPM_GET_CAP_RET_UINT32_4_IDX 26
437 #define TPM_GET_CAP_PERM_DISABLE_IDX 16
438 #define TPM_GET_CAP_PERM_INACTIVE_IDX 18
439 #define TPM_GET_CAP_RET_BOOL_1_IDX 14
440 #define TPM_GET_CAP_TEMP_INACTIVE_IDX 16
441
442 #define TPM_CAP_IDX 13
443 #define TPM_CAP_SUBCAP_IDX 21
444
445 enum tpm_capabilities {
446 TPM_CAP_FLAG = 4,
447 TPM_CAP_PROP = 5,
448 };
449
450 enum tpm_sub_capabilities {
451 TPM_CAP_PROP_PCR = 0x1,
452 TPM_CAP_PROP_MANUFACTURER = 0x3,
453 TPM_CAP_FLAG_PERM = 0x8,
454 TPM_CAP_FLAG_VOL = 0x9,
455 TPM_CAP_PROP_OWNER = 0x11,
456 TPM_CAP_PROP_TIS_TIMEOUT = 0x15,
457 TPM_CAP_PROP_TIS_DURATION = 0x20,
458 };
459
460 /*
461 * This is a semi generic GetCapability command for use
462 * with the capability type TPM_CAP_PROP or TPM_CAP_FLAG
463 * and their associated sub_capabilities.
464 */
465
466 static const u8 tpm_cap[] = {
467 0, 193, /* TPM_TAG_RQU_COMMAND */
468 0, 0, 0, 22, /* length */
469 0, 0, 0, 101, /* TPM_ORD_GetCapability */
470 0, 0, 0, 0, /* TPM_CAP_<TYPE> */
471 0, 0, 0, 4, /* TPM_CAP_SUB_<TYPE> size */
472 0, 0, 1, 0 /* TPM_CAP_SUB_<TYPE> */
473 };
474
transmit_cmd(struct tpm_chip * chip,u8 * data,int len,char * desc)475 static ssize_t transmit_cmd(struct tpm_chip *chip, u8 *data, int len,
476 char *desc)
477 {
478 int err;
479
480 len = tpm_transmit(chip, data, len);
481 if (len < 0)
482 return len;
483 if (len == TPM_ERROR_SIZE) {
484 err = be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX)));
485 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
486 return err;
487 }
488 return 0;
489 }
490
tpm_gen_interrupt(struct tpm_chip * chip)491 void tpm_gen_interrupt(struct tpm_chip *chip)
492 {
493 u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
494 ssize_t rc;
495
496 memcpy(data, tpm_cap, sizeof(tpm_cap));
497 data[TPM_CAP_IDX] = TPM_CAP_PROP;
498 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
499
500 rc = transmit_cmd(chip, data, sizeof(data),
501 "attempting to determine the timeouts");
502 }
503 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
504
tpm_get_timeouts(struct tpm_chip * chip)505 void tpm_get_timeouts(struct tpm_chip *chip)
506 {
507 u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
508 ssize_t rc;
509 u32 timeout;
510
511 memcpy(data, tpm_cap, sizeof(tpm_cap));
512 data[TPM_CAP_IDX] = TPM_CAP_PROP;
513 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
514
515 rc = transmit_cmd(chip, data, sizeof(data),
516 "attempting to determine the timeouts");
517 if (rc)
518 goto duration;
519
520 if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
521 != 4 * sizeof(u32))
522 goto duration;
523
524 /* Don't overwrite default if value is 0 */
525 timeout =
526 be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX)));
527 if (timeout)
528 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
529 timeout =
530 be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_2_IDX)));
531 if (timeout)
532 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
533 timeout =
534 be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_3_IDX)));
535 if (timeout)
536 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
537 timeout =
538 be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_4_IDX)));
539 if (timeout)
540 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
541
542 duration:
543 memcpy(data, tpm_cap, sizeof(tpm_cap));
544 data[TPM_CAP_IDX] = TPM_CAP_PROP;
545 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_DURATION;
546
547 rc = transmit_cmd(chip, data, sizeof(data),
548 "attempting to determine the durations");
549 if (rc)
550 return;
551
552 if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
553 != 3 * sizeof(u32))
554 return;
555
556 chip->vendor.duration[TPM_SHORT] =
557 usecs_to_jiffies(be32_to_cpu
558 (*((__be32 *) (data +
559 TPM_GET_CAP_RET_UINT32_1_IDX))));
560 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
561 * value wrong and apparently reports msecs rather than usecs. So we
562 * fix up the resulting too-small TPM_SHORT value to make things work.
563 */
564 if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
565 chip->vendor.duration[TPM_SHORT] = HZ;
566
567 chip->vendor.duration[TPM_MEDIUM] =
568 usecs_to_jiffies(be32_to_cpu
569 (*((__be32 *) (data +
570 TPM_GET_CAP_RET_UINT32_2_IDX))));
571 chip->vendor.duration[TPM_LONG] =
572 usecs_to_jiffies(be32_to_cpu
573 (*((__be32 *) (data +
574 TPM_GET_CAP_RET_UINT32_3_IDX))));
575 }
576 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
577
tpm_continue_selftest(struct tpm_chip * chip)578 void tpm_continue_selftest(struct tpm_chip *chip)
579 {
580 u8 data[] = {
581 0, 193, /* TPM_TAG_RQU_COMMAND */
582 0, 0, 0, 10, /* length */
583 0, 0, 0, 83, /* TPM_ORD_GetCapability */
584 };
585
586 tpm_transmit(chip, data, sizeof(data));
587 }
588 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
589
590 #define TPM_INTERNAL_RESULT_SIZE 200
591
tpm_show_enabled(struct device * dev,struct device_attribute * attr,char * buf)592 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
593 char *buf)
594 {
595 u8 *data;
596 ssize_t rc;
597
598 struct tpm_chip *chip = dev_get_drvdata(dev);
599 if (chip == NULL)
600 return -ENODEV;
601
602 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
603 if (!data)
604 return -ENOMEM;
605
606 memcpy(data, tpm_cap, sizeof(tpm_cap));
607 data[TPM_CAP_IDX] = TPM_CAP_FLAG;
608 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
609
610 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
611 "attemtping to determine the permanent enabled state");
612 if (rc) {
613 kfree(data);
614 return 0;
615 }
616
617 rc = sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_DISABLE_IDX]);
618
619 kfree(data);
620 return rc;
621 }
622 EXPORT_SYMBOL_GPL(tpm_show_enabled);
623
tpm_show_active(struct device * dev,struct device_attribute * attr,char * buf)624 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
625 char *buf)
626 {
627 u8 *data;
628 ssize_t rc;
629
630 struct tpm_chip *chip = dev_get_drvdata(dev);
631 if (chip == NULL)
632 return -ENODEV;
633
634 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
635 if (!data)
636 return -ENOMEM;
637
638 memcpy(data, tpm_cap, sizeof(tpm_cap));
639 data[TPM_CAP_IDX] = TPM_CAP_FLAG;
640 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
641
642 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
643 "attemtping to determine the permanent active state");
644 if (rc) {
645 kfree(data);
646 return 0;
647 }
648
649 rc = sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_INACTIVE_IDX]);
650
651 kfree(data);
652 return rc;
653 }
654 EXPORT_SYMBOL_GPL(tpm_show_active);
655
tpm_show_owned(struct device * dev,struct device_attribute * attr,char * buf)656 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
657 char *buf)
658 {
659 u8 *data;
660 ssize_t rc;
661
662 struct tpm_chip *chip = dev_get_drvdata(dev);
663 if (chip == NULL)
664 return -ENODEV;
665
666 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
667 if (!data)
668 return -ENOMEM;
669
670 memcpy(data, tpm_cap, sizeof(tpm_cap));
671 data[TPM_CAP_IDX] = TPM_CAP_PROP;
672 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_OWNER;
673
674 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
675 "attempting to determine the owner state");
676 if (rc) {
677 kfree(data);
678 return 0;
679 }
680
681 rc = sprintf(buf, "%d\n", data[TPM_GET_CAP_RET_BOOL_1_IDX]);
682
683 kfree(data);
684 return rc;
685 }
686 EXPORT_SYMBOL_GPL(tpm_show_owned);
687
tpm_show_temp_deactivated(struct device * dev,struct device_attribute * attr,char * buf)688 ssize_t tpm_show_temp_deactivated(struct device * dev,
689 struct device_attribute * attr, char *buf)
690 {
691 u8 *data;
692 ssize_t rc;
693
694 struct tpm_chip *chip = dev_get_drvdata(dev);
695 if (chip == NULL)
696 return -ENODEV;
697
698 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
699 if (!data)
700 return -ENOMEM;
701
702 memcpy(data, tpm_cap, sizeof(tpm_cap));
703 data[TPM_CAP_IDX] = TPM_CAP_FLAG;
704 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_VOL;
705
706 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
707 "attempting to determine the temporary state");
708 if (rc) {
709 kfree(data);
710 return 0;
711 }
712
713 rc = sprintf(buf, "%d\n", data[TPM_GET_CAP_TEMP_INACTIVE_IDX]);
714
715 kfree(data);
716 return rc;
717 }
718 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
719
720 static const u8 pcrread[] = {
721 0, 193, /* TPM_TAG_RQU_COMMAND */
722 0, 0, 0, 14, /* length */
723 0, 0, 0, 21, /* TPM_ORD_PcrRead */
724 0, 0, 0, 0 /* PCR index */
725 };
726
tpm_show_pcrs(struct device * dev,struct device_attribute * attr,char * buf)727 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
728 char *buf)
729 {
730 u8 *data;
731 ssize_t rc;
732 int i, j, num_pcrs;
733 __be32 index;
734 char *str = buf;
735
736 struct tpm_chip *chip = dev_get_drvdata(dev);
737 if (chip == NULL)
738 return -ENODEV;
739
740 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
741 if (!data)
742 return -ENOMEM;
743
744 memcpy(data, tpm_cap, sizeof(tpm_cap));
745 data[TPM_CAP_IDX] = TPM_CAP_PROP;
746 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_PCR;
747
748 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
749 "attempting to determine the number of PCRS");
750 if (rc) {
751 kfree(data);
752 return 0;
753 }
754
755 num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
756 for (i = 0; i < num_pcrs; i++) {
757 memcpy(data, pcrread, sizeof(pcrread));
758 index = cpu_to_be32(i);
759 memcpy(data + 10, &index, 4);
760 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
761 "attempting to read a PCR");
762 if (rc)
763 goto out;
764 str += sprintf(str, "PCR-%02d: ", i);
765 for (j = 0; j < TPM_DIGEST_SIZE; j++)
766 str += sprintf(str, "%02X ", *(data + 10 + j));
767 str += sprintf(str, "\n");
768 }
769 out:
770 kfree(data);
771 return str - buf;
772 }
773 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
774
775 #define READ_PUBEK_RESULT_SIZE 314
776 static const u8 readpubek[] = {
777 0, 193, /* TPM_TAG_RQU_COMMAND */
778 0, 0, 0, 30, /* length */
779 0, 0, 0, 124, /* TPM_ORD_ReadPubek */
780 };
781
tpm_show_pubek(struct device * dev,struct device_attribute * attr,char * buf)782 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
783 char *buf)
784 {
785 u8 *data;
786 ssize_t err;
787 int i, rc;
788 char *str = buf;
789
790 struct tpm_chip *chip = dev_get_drvdata(dev);
791 if (chip == NULL)
792 return -ENODEV;
793
794 data = kzalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
795 if (!data)
796 return -ENOMEM;
797
798 memcpy(data, readpubek, sizeof(readpubek));
799
800 err = transmit_cmd(chip, data, READ_PUBEK_RESULT_SIZE,
801 "attempting to read the PUBEK");
802 if (err)
803 goto out;
804
805 /*
806 ignore header 10 bytes
807 algorithm 32 bits (1 == RSA )
808 encscheme 16 bits
809 sigscheme 16 bits
810 parameters (RSA 12->bytes: keybit, #primes, expbit)
811 keylenbytes 32 bits
812 256 byte modulus
813 ignore checksum 20 bytes
814 */
815
816 str +=
817 sprintf(str,
818 "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
819 "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
820 " %02X %02X %02X %02X %02X %02X %02X %02X\n"
821 "Modulus length: %d\nModulus: \n",
822 data[10], data[11], data[12], data[13], data[14],
823 data[15], data[16], data[17], data[22], data[23],
824 data[24], data[25], data[26], data[27], data[28],
825 data[29], data[30], data[31], data[32], data[33],
826 be32_to_cpu(*((__be32 *) (data + 34))));
827
828 for (i = 0; i < 256; i++) {
829 str += sprintf(str, "%02X ", data[i + 38]);
830 if ((i + 1) % 16 == 0)
831 str += sprintf(str, "\n");
832 }
833 out:
834 rc = str - buf;
835 kfree(data);
836 return rc;
837 }
838 EXPORT_SYMBOL_GPL(tpm_show_pubek);
839
840 #define CAP_VERSION_1_1 6
841 #define CAP_VERSION_1_2 0x1A
842 #define CAP_VERSION_IDX 13
843 static const u8 cap_version[] = {
844 0, 193, /* TPM_TAG_RQU_COMMAND */
845 0, 0, 0, 18, /* length */
846 0, 0, 0, 101, /* TPM_ORD_GetCapability */
847 0, 0, 0, 0,
848 0, 0, 0, 0
849 };
850
tpm_show_caps(struct device * dev,struct device_attribute * attr,char * buf)851 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
852 char *buf)
853 {
854 u8 *data;
855 ssize_t rc;
856 char *str = buf;
857
858 struct tpm_chip *chip = dev_get_drvdata(dev);
859 if (chip == NULL)
860 return -ENODEV;
861
862 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
863 if (!data)
864 return -ENOMEM;
865
866 memcpy(data, tpm_cap, sizeof(tpm_cap));
867 data[TPM_CAP_IDX] = TPM_CAP_PROP;
868 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
869
870 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
871 "attempting to determine the manufacturer");
872 if (rc) {
873 kfree(data);
874 return 0;
875 }
876
877 str += sprintf(str, "Manufacturer: 0x%x\n",
878 be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
879
880 memcpy(data, cap_version, sizeof(cap_version));
881 data[CAP_VERSION_IDX] = CAP_VERSION_1_1;
882 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
883 "attempting to determine the 1.1 version");
884 if (rc)
885 goto out;
886
887 str += sprintf(str,
888 "TCG version: %d.%d\nFirmware version: %d.%d\n",
889 (int) data[14], (int) data[15], (int) data[16],
890 (int) data[17]);
891
892 out:
893 kfree(data);
894 return str - buf;
895 }
896 EXPORT_SYMBOL_GPL(tpm_show_caps);
897
tpm_show_caps_1_2(struct device * dev,struct device_attribute * attr,char * buf)898 ssize_t tpm_show_caps_1_2(struct device * dev,
899 struct device_attribute * attr, char *buf)
900 {
901 u8 *data;
902 ssize_t len;
903 char *str = buf;
904
905 struct tpm_chip *chip = dev_get_drvdata(dev);
906 if (chip == NULL)
907 return -ENODEV;
908
909 data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
910 if (!data)
911 return -ENOMEM;
912
913 memcpy(data, tpm_cap, sizeof(tpm_cap));
914 data[TPM_CAP_IDX] = TPM_CAP_PROP;
915 data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
916
917 len = tpm_transmit(chip, data, TPM_INTERNAL_RESULT_SIZE);
918 if (len <= TPM_ERROR_SIZE) {
919 dev_dbg(chip->dev, "A TPM error (%d) occurred "
920 "attempting to determine the manufacturer\n",
921 be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
922 kfree(data);
923 return 0;
924 }
925
926 str += sprintf(str, "Manufacturer: 0x%x\n",
927 be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
928
929 memcpy(data, cap_version, sizeof(cap_version));
930 data[CAP_VERSION_IDX] = CAP_VERSION_1_2;
931
932 len = tpm_transmit(chip, data, TPM_INTERNAL_RESULT_SIZE);
933 if (len <= TPM_ERROR_SIZE) {
934 dev_err(chip->dev, "A TPM error (%d) occurred "
935 "attempting to determine the 1.2 version\n",
936 be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
937 goto out;
938 }
939 str += sprintf(str,
940 "TCG version: %d.%d\nFirmware version: %d.%d\n",
941 (int) data[16], (int) data[17], (int) data[18],
942 (int) data[19]);
943
944 out:
945 kfree(data);
946 return str - buf;
947 }
948 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
949
tpm_store_cancel(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)950 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
951 const char *buf, size_t count)
952 {
953 struct tpm_chip *chip = dev_get_drvdata(dev);
954 if (chip == NULL)
955 return 0;
956
957 chip->vendor.cancel(chip);
958 return count;
959 }
960 EXPORT_SYMBOL_GPL(tpm_store_cancel);
961
962 /*
963 * Device file system interface to the TPM
964 *
965 * It's assured that the chip will be opened just once,
966 * by the check of is_open variable, which is protected
967 * by driver_lock.
968 */
tpm_open(struct inode * inode,struct file * file)969 int tpm_open(struct inode *inode, struct file *file)
970 {
971 int minor = iminor(inode);
972 struct tpm_chip *chip = NULL, *pos;
973
974 rcu_read_lock();
975 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
976 if (pos->vendor.miscdev.minor == minor) {
977 chip = pos;
978 get_device(chip->dev);
979 break;
980 }
981 }
982 rcu_read_unlock();
983
984 if (!chip)
985 return -ENODEV;
986
987 if (test_and_set_bit(0, &chip->is_open)) {
988 dev_dbg(chip->dev, "Another process owns this TPM\n");
989 put_device(chip->dev);
990 return -EBUSY;
991 }
992
993 chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
994 if (chip->data_buffer == NULL) {
995 clear_bit(0, &chip->is_open);
996 put_device(chip->dev);
997 return -ENOMEM;
998 }
999
1000 atomic_set(&chip->data_pending, 0);
1001
1002 file->private_data = chip;
1003 return 0;
1004 }
1005 EXPORT_SYMBOL_GPL(tpm_open);
1006
1007 /*
1008 * Called on file close
1009 */
tpm_release(struct inode * inode,struct file * file)1010 int tpm_release(struct inode *inode, struct file *file)
1011 {
1012 struct tpm_chip *chip = file->private_data;
1013
1014 del_singleshot_timer_sync(&chip->user_read_timer);
1015 flush_scheduled_work();
1016 file->private_data = NULL;
1017 atomic_set(&chip->data_pending, 0);
1018 kfree(chip->data_buffer);
1019 clear_bit(0, &chip->is_open);
1020 put_device(chip->dev);
1021 return 0;
1022 }
1023 EXPORT_SYMBOL_GPL(tpm_release);
1024
tpm_write(struct file * file,const char __user * buf,size_t size,loff_t * off)1025 ssize_t tpm_write(struct file *file, const char __user *buf,
1026 size_t size, loff_t *off)
1027 {
1028 struct tpm_chip *chip = file->private_data;
1029 size_t in_size = size, out_size;
1030
1031 /* cannot perform a write until the read has cleared
1032 either via tpm_read or a user_read_timer timeout */
1033 while (atomic_read(&chip->data_pending) != 0)
1034 msleep(TPM_TIMEOUT);
1035
1036 mutex_lock(&chip->buffer_mutex);
1037
1038 if (in_size > TPM_BUFSIZE)
1039 in_size = TPM_BUFSIZE;
1040
1041 if (copy_from_user
1042 (chip->data_buffer, (void __user *) buf, in_size)) {
1043 mutex_unlock(&chip->buffer_mutex);
1044 return -EFAULT;
1045 }
1046
1047 /* atomic tpm command send and result receive */
1048 out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1049
1050 atomic_set(&chip->data_pending, out_size);
1051 mutex_unlock(&chip->buffer_mutex);
1052
1053 /* Set a timeout by which the reader must come claim the result */
1054 mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1055
1056 return in_size;
1057 }
1058 EXPORT_SYMBOL_GPL(tpm_write);
1059
tpm_read(struct file * file,char __user * buf,size_t size,loff_t * off)1060 ssize_t tpm_read(struct file *file, char __user *buf,
1061 size_t size, loff_t *off)
1062 {
1063 struct tpm_chip *chip = file->private_data;
1064 ssize_t ret_size;
1065
1066 del_singleshot_timer_sync(&chip->user_read_timer);
1067 flush_scheduled_work();
1068 ret_size = atomic_read(&chip->data_pending);
1069 atomic_set(&chip->data_pending, 0);
1070 if (ret_size > 0) { /* relay data */
1071 if (size < ret_size)
1072 ret_size = size;
1073
1074 mutex_lock(&chip->buffer_mutex);
1075 if (copy_to_user(buf, chip->data_buffer, ret_size))
1076 ret_size = -EFAULT;
1077 mutex_unlock(&chip->buffer_mutex);
1078 }
1079
1080 return ret_size;
1081 }
1082 EXPORT_SYMBOL_GPL(tpm_read);
1083
tpm_remove_hardware(struct device * dev)1084 void tpm_remove_hardware(struct device *dev)
1085 {
1086 struct tpm_chip *chip = dev_get_drvdata(dev);
1087
1088 if (chip == NULL) {
1089 dev_err(dev, "No device data found\n");
1090 return;
1091 }
1092
1093 spin_lock(&driver_lock);
1094 list_del_rcu(&chip->list);
1095 spin_unlock(&driver_lock);
1096 synchronize_rcu();
1097
1098 misc_deregister(&chip->vendor.miscdev);
1099 sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1100 tpm_bios_log_teardown(chip->bios_dir);
1101
1102 /* write it this way to be explicit (chip->dev == dev) */
1103 put_device(chip->dev);
1104 }
1105 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1106
1107 /*
1108 * We are about to suspend. Save the TPM state
1109 * so that it can be restored.
1110 */
tpm_pm_suspend(struct device * dev,pm_message_t pm_state)1111 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1112 {
1113 struct tpm_chip *chip = dev_get_drvdata(dev);
1114 u8 savestate[] = {
1115 0, 193, /* TPM_TAG_RQU_COMMAND */
1116 0, 0, 0, 10, /* blob length (in bytes) */
1117 0, 0, 0, 152 /* TPM_ORD_SaveState */
1118 };
1119
1120 if (chip == NULL)
1121 return -ENODEV;
1122
1123 tpm_transmit(chip, savestate, sizeof(savestate));
1124 return 0;
1125 }
1126 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1127
1128 /*
1129 * Resume from a power safe. The BIOS already restored
1130 * the TPM state.
1131 */
tpm_pm_resume(struct device * dev)1132 int tpm_pm_resume(struct device *dev)
1133 {
1134 struct tpm_chip *chip = dev_get_drvdata(dev);
1135
1136 if (chip == NULL)
1137 return -ENODEV;
1138
1139 return 0;
1140 }
1141 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1142
1143 /* In case vendor provided release function, call it too.*/
1144
tpm_dev_vendor_release(struct tpm_chip * chip)1145 void tpm_dev_vendor_release(struct tpm_chip *chip)
1146 {
1147 if (chip->vendor.release)
1148 chip->vendor.release(chip->dev);
1149
1150 clear_bit(chip->dev_num, dev_mask);
1151 kfree(chip->vendor.miscdev.name);
1152 }
1153 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1154
1155
1156 /*
1157 * Once all references to platform device are down to 0,
1158 * release all allocated structures.
1159 */
tpm_dev_release(struct device * dev)1160 void tpm_dev_release(struct device *dev)
1161 {
1162 struct tpm_chip *chip = dev_get_drvdata(dev);
1163
1164 tpm_dev_vendor_release(chip);
1165
1166 chip->release(dev);
1167 kfree(chip);
1168 }
1169 EXPORT_SYMBOL_GPL(tpm_dev_release);
1170
1171 /*
1172 * Called from tpm_<specific>.c probe function only for devices
1173 * the driver has determined it should claim. Prior to calling
1174 * this function the specific probe function has called pci_enable_device
1175 * upon errant exit from this function specific probe function should call
1176 * pci_disable_device
1177 */
tpm_register_hardware(struct device * dev,const struct tpm_vendor_specific * entry)1178 struct tpm_chip *tpm_register_hardware(struct device *dev,
1179 const struct tpm_vendor_specific *entry)
1180 {
1181 #define DEVNAME_SIZE 7
1182
1183 char *devname;
1184 struct tpm_chip *chip;
1185
1186 /* Driver specific per-device data */
1187 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1188 devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1189
1190 if (chip == NULL || devname == NULL)
1191 goto out_free;
1192
1193 mutex_init(&chip->buffer_mutex);
1194 mutex_init(&chip->tpm_mutex);
1195 INIT_LIST_HEAD(&chip->list);
1196
1197 INIT_WORK(&chip->work, timeout_work);
1198
1199 setup_timer(&chip->user_read_timer, user_reader_timeout,
1200 (unsigned long)chip);
1201
1202 memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1203
1204 chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1205
1206 if (chip->dev_num >= TPM_NUM_DEVICES) {
1207 dev_err(dev, "No available tpm device numbers\n");
1208 goto out_free;
1209 } else if (chip->dev_num == 0)
1210 chip->vendor.miscdev.minor = TPM_MINOR;
1211 else
1212 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1213
1214 set_bit(chip->dev_num, dev_mask);
1215
1216 scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1217 chip->vendor.miscdev.name = devname;
1218
1219 chip->vendor.miscdev.parent = dev;
1220 chip->dev = get_device(dev);
1221 chip->release = dev->release;
1222 dev->release = tpm_dev_release;
1223 dev_set_drvdata(dev, chip);
1224
1225 if (misc_register(&chip->vendor.miscdev)) {
1226 dev_err(chip->dev,
1227 "unable to misc_register %s, minor %d\n",
1228 chip->vendor.miscdev.name,
1229 chip->vendor.miscdev.minor);
1230 put_device(chip->dev);
1231 return NULL;
1232 }
1233
1234 if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1235 misc_deregister(&chip->vendor.miscdev);
1236 put_device(chip->dev);
1237
1238 return NULL;
1239 }
1240
1241 chip->bios_dir = tpm_bios_log_setup(devname);
1242
1243 /* Make chip available */
1244 spin_lock(&driver_lock);
1245 list_add_rcu(&chip->list, &tpm_chip_list);
1246 spin_unlock(&driver_lock);
1247
1248 return chip;
1249
1250 out_free:
1251 kfree(chip);
1252 kfree(devname);
1253 return NULL;
1254 }
1255 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1256
1257 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1258 MODULE_DESCRIPTION("TPM Driver");
1259 MODULE_VERSION("2.0");
1260 MODULE_LICENSE("GPL");
1261