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TPM: Long default timeout fix
[karo-tx-linux.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
31 #include "tpm.h"
32
33 enum tpm_const {
34         TPM_MINOR = 224,        /* officially assigned */
35         TPM_BUFSIZE = 4096,
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
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
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  */
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 is 0, it's because chip->vendor.duration wasn't */
360                 /* filled yet, so we set the lowest timeout just to give enough */
361                 /* time for tpm_get_timeouts() to succeed */
362                 return (duration <= 0 ? HZ : duration);
363         } else
364                 return 2 * 60 * HZ;
365 }
366 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
367
368 /*
369  * Internal kernel interface to transmit TPM commands
370  */
371 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
372                             size_t bufsiz)
373 {
374         ssize_t rc;
375         u32 count, ordinal;
376         unsigned long stop;
377
378         count = be32_to_cpu(*((__be32 *) (buf + 2)));
379         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
380         if (count == 0)
381                 return -ENODATA;
382         if (count > bufsiz) {
383                 dev_err(chip->dev,
384                         "invalid count value %x %zx \n", count, bufsiz);
385                 return -E2BIG;
386         }
387
388         mutex_lock(&chip->tpm_mutex);
389
390         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
391                 dev_err(chip->dev,
392                         "tpm_transmit: tpm_send: error %zd\n", rc);
393                 goto out;
394         }
395
396         if (chip->vendor.irq)
397                 goto out_recv;
398
399         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
400         do {
401                 u8 status = chip->vendor.status(chip);
402                 if ((status & chip->vendor.req_complete_mask) ==
403                     chip->vendor.req_complete_val)
404                         goto out_recv;
405
406                 if ((status == chip->vendor.req_canceled)) {
407                         dev_err(chip->dev, "Operation Canceled\n");
408                         rc = -ECANCELED;
409                         goto out;
410                 }
411
412                 msleep(TPM_TIMEOUT);    /* CHECK */
413                 rmb();
414         } while (time_before(jiffies, stop));
415
416         chip->vendor.cancel(chip);
417         dev_err(chip->dev, "Operation Timed out\n");
418         rc = -ETIME;
419         goto out;
420
421 out_recv:
422         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
423         if (rc < 0)
424                 dev_err(chip->dev,
425                         "tpm_transmit: tpm_recv: error %zd\n", rc);
426 out:
427         mutex_unlock(&chip->tpm_mutex);
428         return rc;
429 }
430
431 #define TPM_DIGEST_SIZE 20
432 #define TPM_ERROR_SIZE 10
433 #define TPM_RET_CODE_IDX 6
434
435 enum tpm_capabilities {
436         TPM_CAP_FLAG = cpu_to_be32(4),
437         TPM_CAP_PROP = cpu_to_be32(5),
438         CAP_VERSION_1_1 = cpu_to_be32(0x06),
439         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
440 };
441
442 enum tpm_sub_capabilities {
443         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
444         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
445         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
446         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
447         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
448         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
449         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
450
451 };
452
453 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
454                             int len, const char *desc)
455 {
456         int err;
457
458         len = tpm_transmit(chip,(u8 *) cmd, len);
459         if (len <  0)
460                 return len;
461         if (len == TPM_ERROR_SIZE) {
462                 err = be32_to_cpu(cmd->header.out.return_code);
463                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
464                 return err;
465         }
466         return 0;
467 }
468
469 #define TPM_INTERNAL_RESULT_SIZE 200
470 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
471 #define TPM_ORD_GET_CAP cpu_to_be32(101)
472
473 static const struct tpm_input_header tpm_getcap_header = {
474         .tag = TPM_TAG_RQU_COMMAND,
475         .length = cpu_to_be32(22),
476         .ordinal = TPM_ORD_GET_CAP
477 };
478
479 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
480                    const char *desc)
481 {
482         struct tpm_cmd_t tpm_cmd;
483         int rc;
484         struct tpm_chip *chip = dev_get_drvdata(dev);
485
486         tpm_cmd.header.in = tpm_getcap_header;
487         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
488                 tpm_cmd.params.getcap_in.cap = subcap_id;
489                 /*subcap field not necessary */
490                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
491                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
492         } else {
493                 if (subcap_id == TPM_CAP_FLAG_PERM ||
494                     subcap_id == TPM_CAP_FLAG_VOL)
495                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
496                 else
497                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
498                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
499                 tpm_cmd.params.getcap_in.subcap = subcap_id;
500         }
501         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
502         if (!rc)
503                 *cap = tpm_cmd.params.getcap_out.cap;
504         return rc;
505 }
506
507 void tpm_gen_interrupt(struct tpm_chip *chip)
508 {
509         struct  tpm_cmd_t tpm_cmd;
510         ssize_t rc;
511
512         tpm_cmd.header.in = tpm_getcap_header;
513         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
514         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
515         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
516
517         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
518                         "attempting to determine the timeouts");
519 }
520 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
521
522 void tpm_get_timeouts(struct tpm_chip *chip)
523 {
524         struct tpm_cmd_t tpm_cmd;
525         struct timeout_t *timeout_cap;
526         struct duration_t *duration_cap;
527         ssize_t rc;
528         u32 timeout;
529
530         tpm_cmd.header.in = tpm_getcap_header;
531         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
532         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
533         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
534
535         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
536                         "attempting to determine the timeouts");
537         if (rc)
538                 goto duration;
539
540         if (be32_to_cpu(tpm_cmd.header.out.length)
541             != 4 * sizeof(u32))
542                 goto duration;
543
544         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
545         /* Don't overwrite default if value is 0 */
546         timeout = be32_to_cpu(timeout_cap->a);
547         if (timeout)
548                 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
549         timeout = be32_to_cpu(timeout_cap->b);
550         if (timeout)
551                 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
552         timeout = be32_to_cpu(timeout_cap->c);
553         if (timeout)
554                 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
555         timeout = be32_to_cpu(timeout_cap->d);
556         if (timeout)
557                 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
558
559 duration:
560         tpm_cmd.header.in = tpm_getcap_header;
561         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
562         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
563         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
564
565         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
566                         "attempting to determine the durations");
567         if (rc)
568                 return;
569
570         if (be32_to_cpu(tpm_cmd.header.out.return_code)
571             != 3 * sizeof(u32))
572                 return;
573         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
574         chip->vendor.duration[TPM_SHORT] =
575             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
576         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
577          * value wrong and apparently reports msecs rather than usecs. So we
578          * fix up the resulting too-small TPM_SHORT value to make things work.
579          */
580         if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
581                 chip->vendor.duration[TPM_SHORT] = HZ;
582
583         chip->vendor.duration[TPM_MEDIUM] =
584             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
585         chip->vendor.duration[TPM_LONG] =
586             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
587 }
588 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
589
590 void tpm_continue_selftest(struct tpm_chip *chip)
591 {
592         u8 data[] = {
593                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
594                 0, 0, 0, 10,            /* length */
595                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
596         };
597
598         tpm_transmit(chip, data, sizeof(data));
599 }
600 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
601
602 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
603                         char *buf)
604 {
605         cap_t cap;
606         ssize_t rc;
607
608         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
609                          "attempting to determine the permanent enabled state");
610         if (rc)
611                 return 0;
612
613         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
614         return rc;
615 }
616 EXPORT_SYMBOL_GPL(tpm_show_enabled);
617
618 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
619                         char *buf)
620 {
621         cap_t cap;
622         ssize_t rc;
623
624         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
625                          "attempting to determine the permanent active state");
626         if (rc)
627                 return 0;
628
629         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
630         return rc;
631 }
632 EXPORT_SYMBOL_GPL(tpm_show_active);
633
634 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
635                         char *buf)
636 {
637         cap_t cap;
638         ssize_t rc;
639
640         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
641                          "attempting to determine the owner state");
642         if (rc)
643                 return 0;
644
645         rc = sprintf(buf, "%d\n", cap.owned);
646         return rc;
647 }
648 EXPORT_SYMBOL_GPL(tpm_show_owned);
649
650 ssize_t tpm_show_temp_deactivated(struct device * dev,
651                                 struct device_attribute * attr, char *buf)
652 {
653         cap_t cap;
654         ssize_t rc;
655
656         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
657                          "attempting to determine the temporary state");
658         if (rc)
659                 return 0;
660
661         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
662         return rc;
663 }
664 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
665
666 /*
667  * tpm_chip_find_get - return tpm_chip for given chip number
668  */
669 static struct tpm_chip *tpm_chip_find_get(int chip_num)
670 {
671         struct tpm_chip *pos, *chip = NULL;
672
673         rcu_read_lock();
674         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
675                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
676                         continue;
677
678                 if (try_module_get(pos->dev->driver->owner)) {
679                         chip = pos;
680                         break;
681                 }
682         }
683         rcu_read_unlock();
684         return chip;
685 }
686
687 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
688 #define READ_PCR_RESULT_SIZE 30
689 static struct tpm_input_header pcrread_header = {
690         .tag = TPM_TAG_RQU_COMMAND,
691         .length = cpu_to_be32(14),
692         .ordinal = TPM_ORDINAL_PCRREAD
693 };
694
695 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
696 {
697         int rc;
698         struct tpm_cmd_t cmd;
699
700         cmd.header.in = pcrread_header;
701         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
702         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
703                           "attempting to read a pcr value");
704
705         if (rc == 0)
706                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
707                        TPM_DIGEST_SIZE);
708         return rc;
709 }
710
711 /**
712  * tpm_pcr_read - read a pcr value
713  * @chip_num:   tpm idx # or ANY
714  * @pcr_idx:    pcr idx to retrieve
715  * @res_buf:    TPM_PCR value
716  *              size of res_buf is 20 bytes (or NULL if you don't care)
717  *
718  * The TPM driver should be built-in, but for whatever reason it
719  * isn't, protect against the chip disappearing, by incrementing
720  * the module usage count.
721  */
722 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
723 {
724         struct tpm_chip *chip;
725         int rc;
726
727         chip = tpm_chip_find_get(chip_num);
728         if (chip == NULL)
729                 return -ENODEV;
730         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
731         module_put(chip->dev->driver->owner);
732         return rc;
733 }
734 EXPORT_SYMBOL_GPL(tpm_pcr_read);
735
736 /**
737  * tpm_pcr_extend - extend pcr value with hash
738  * @chip_num:   tpm idx # or AN&
739  * @pcr_idx:    pcr idx to extend
740  * @hash:       hash value used to extend pcr value
741  *
742  * The TPM driver should be built-in, but for whatever reason it
743  * isn't, protect against the chip disappearing, by incrementing
744  * the module usage count.
745  */
746 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
747 #define EXTEND_PCR_RESULT_SIZE 34
748 static struct tpm_input_header pcrextend_header = {
749         .tag = TPM_TAG_RQU_COMMAND,
750         .length = cpu_to_be32(34),
751         .ordinal = TPM_ORD_PCR_EXTEND
752 };
753
754 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
755 {
756         struct tpm_cmd_t cmd;
757         int rc;
758         struct tpm_chip *chip;
759
760         chip = tpm_chip_find_get(chip_num);
761         if (chip == NULL)
762                 return -ENODEV;
763
764         cmd.header.in = pcrextend_header;
765         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
766         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
767         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
768                           "attempting extend a PCR value");
769
770         module_put(chip->dev->driver->owner);
771         return rc;
772 }
773 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
774
775 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
776                       char *buf)
777 {
778         cap_t cap;
779         u8 digest[TPM_DIGEST_SIZE];
780         ssize_t rc;
781         int i, j, num_pcrs;
782         char *str = buf;
783         struct tpm_chip *chip = dev_get_drvdata(dev);
784
785         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
786                         "attempting to determine the number of PCRS");
787         if (rc)
788                 return 0;
789
790         num_pcrs = be32_to_cpu(cap.num_pcrs);
791         for (i = 0; i < num_pcrs; i++) {
792                 rc = __tpm_pcr_read(chip, i, digest);
793                 if (rc)
794                         break;
795                 str += sprintf(str, "PCR-%02d: ", i);
796                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
797                         str += sprintf(str, "%02X ", digest[j]);
798                 str += sprintf(str, "\n");
799         }
800         return str - buf;
801 }
802 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
803
804 #define  READ_PUBEK_RESULT_SIZE 314
805 #define TPM_ORD_READPUBEK cpu_to_be32(124)
806 struct tpm_input_header tpm_readpubek_header = {
807         .tag = TPM_TAG_RQU_COMMAND,
808         .length = cpu_to_be32(30),
809         .ordinal = TPM_ORD_READPUBEK
810 };
811
812 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
813                        char *buf)
814 {
815         u8 *data;
816         struct tpm_cmd_t tpm_cmd;
817         ssize_t err;
818         int i, rc;
819         char *str = buf;
820
821         struct tpm_chip *chip = dev_get_drvdata(dev);
822
823         tpm_cmd.header.in = tpm_readpubek_header;
824         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
825                         "attempting to read the PUBEK");
826         if (err)
827                 goto out;
828
829         /* 
830            ignore header 10 bytes
831            algorithm 32 bits (1 == RSA )
832            encscheme 16 bits
833            sigscheme 16 bits
834            parameters (RSA 12->bytes: keybit, #primes, expbit)  
835            keylenbytes 32 bits
836            256 byte modulus
837            ignore checksum 20 bytes
838          */
839         data = tpm_cmd.params.readpubek_out_buffer;
840         str +=
841             sprintf(str,
842                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
843                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
844                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
845                     "Modulus length: %d\nModulus: \n",
846                     data[10], data[11], data[12], data[13], data[14],
847                     data[15], data[16], data[17], data[22], data[23],
848                     data[24], data[25], data[26], data[27], data[28],
849                     data[29], data[30], data[31], data[32], data[33],
850                     be32_to_cpu(*((__be32 *) (data + 34))));
851
852         for (i = 0; i < 256; i++) {
853                 str += sprintf(str, "%02X ", data[i + 38]);
854                 if ((i + 1) % 16 == 0)
855                         str += sprintf(str, "\n");
856         }
857 out:
858         rc = str - buf;
859         return rc;
860 }
861 EXPORT_SYMBOL_GPL(tpm_show_pubek);
862
863
864 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
865                       char *buf)
866 {
867         cap_t cap;
868         ssize_t rc;
869         char *str = buf;
870
871         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
872                         "attempting to determine the manufacturer");
873         if (rc)
874                 return 0;
875         str += sprintf(str, "Manufacturer: 0x%x\n",
876                        be32_to_cpu(cap.manufacturer_id));
877
878         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
879                         "attempting to determine the 1.1 version");
880         if (rc)
881                 return 0;
882         str += sprintf(str,
883                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
884                        cap.tpm_version.Major, cap.tpm_version.Minor,
885                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
886         return str - buf;
887 }
888 EXPORT_SYMBOL_GPL(tpm_show_caps);
889
890 ssize_t tpm_show_caps_1_2(struct device * dev,
891                           struct device_attribute * attr, char *buf)
892 {
893         cap_t cap;
894         ssize_t rc;
895         char *str = buf;
896
897         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
898                         "attempting to determine the manufacturer");
899         if (rc)
900                 return 0;
901         str += sprintf(str, "Manufacturer: 0x%x\n",
902                        be32_to_cpu(cap.manufacturer_id));
903         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
904                          "attempting to determine the 1.2 version");
905         if (rc)
906                 return 0;
907         str += sprintf(str,
908                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
909                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
910                        cap.tpm_version_1_2.revMajor,
911                        cap.tpm_version_1_2.revMinor);
912         return str - buf;
913 }
914 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
915
916 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
917                         const char *buf, size_t count)
918 {
919         struct tpm_chip *chip = dev_get_drvdata(dev);
920         if (chip == NULL)
921                 return 0;
922
923         chip->vendor.cancel(chip);
924         return count;
925 }
926 EXPORT_SYMBOL_GPL(tpm_store_cancel);
927
928 /*
929  * Device file system interface to the TPM
930  *
931  * It's assured that the chip will be opened just once,
932  * by the check of is_open variable, which is protected
933  * by driver_lock.
934  */
935 int tpm_open(struct inode *inode, struct file *file)
936 {
937         int minor = iminor(inode);
938         struct tpm_chip *chip = NULL, *pos;
939
940         rcu_read_lock();
941         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
942                 if (pos->vendor.miscdev.minor == minor) {
943                         chip = pos;
944                         get_device(chip->dev);
945                         break;
946                 }
947         }
948         rcu_read_unlock();
949
950         if (!chip)
951                 return -ENODEV;
952
953         if (test_and_set_bit(0, &chip->is_open)) {
954                 dev_dbg(chip->dev, "Another process owns this TPM\n");
955                 put_device(chip->dev);
956                 return -EBUSY;
957         }
958
959         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
960         if (chip->data_buffer == NULL) {
961                 clear_bit(0, &chip->is_open);
962                 put_device(chip->dev);
963                 return -ENOMEM;
964         }
965
966         atomic_set(&chip->data_pending, 0);
967
968         file->private_data = chip;
969         return 0;
970 }
971 EXPORT_SYMBOL_GPL(tpm_open);
972
973 /*
974  * Called on file close
975  */
976 int tpm_release(struct inode *inode, struct file *file)
977 {
978         struct tpm_chip *chip = file->private_data;
979
980         del_singleshot_timer_sync(&chip->user_read_timer);
981         flush_scheduled_work();
982         file->private_data = NULL;
983         atomic_set(&chip->data_pending, 0);
984         kfree(chip->data_buffer);
985         clear_bit(0, &chip->is_open);
986         put_device(chip->dev);
987         return 0;
988 }
989 EXPORT_SYMBOL_GPL(tpm_release);
990
991 ssize_t tpm_write(struct file *file, const char __user *buf,
992                   size_t size, loff_t *off)
993 {
994         struct tpm_chip *chip = file->private_data;
995         size_t in_size = size, out_size;
996
997         /* cannot perform a write until the read has cleared
998            either via tpm_read or a user_read_timer timeout */
999         while (atomic_read(&chip->data_pending) != 0)
1000                 msleep(TPM_TIMEOUT);
1001
1002         mutex_lock(&chip->buffer_mutex);
1003
1004         if (in_size > TPM_BUFSIZE)
1005                 in_size = TPM_BUFSIZE;
1006
1007         if (copy_from_user
1008             (chip->data_buffer, (void __user *) buf, in_size)) {
1009                 mutex_unlock(&chip->buffer_mutex);
1010                 return -EFAULT;
1011         }
1012
1013         /* atomic tpm command send and result receive */
1014         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1015
1016         atomic_set(&chip->data_pending, out_size);
1017         mutex_unlock(&chip->buffer_mutex);
1018
1019         /* Set a timeout by which the reader must come claim the result */
1020         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1021
1022         return in_size;
1023 }
1024 EXPORT_SYMBOL_GPL(tpm_write);
1025
1026 ssize_t tpm_read(struct file *file, char __user *buf,
1027                  size_t size, loff_t *off)
1028 {
1029         struct tpm_chip *chip = file->private_data;
1030         ssize_t ret_size;
1031
1032         del_singleshot_timer_sync(&chip->user_read_timer);
1033         flush_scheduled_work();
1034         ret_size = atomic_read(&chip->data_pending);
1035         atomic_set(&chip->data_pending, 0);
1036         if (ret_size > 0) {     /* relay data */
1037                 if (size < ret_size)
1038                         ret_size = size;
1039
1040                 mutex_lock(&chip->buffer_mutex);
1041                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1042                         ret_size = -EFAULT;
1043                 mutex_unlock(&chip->buffer_mutex);
1044         }
1045
1046         return ret_size;
1047 }
1048 EXPORT_SYMBOL_GPL(tpm_read);
1049
1050 void tpm_remove_hardware(struct device *dev)
1051 {
1052         struct tpm_chip *chip = dev_get_drvdata(dev);
1053
1054         if (chip == NULL) {
1055                 dev_err(dev, "No device data found\n");
1056                 return;
1057         }
1058
1059         spin_lock(&driver_lock);
1060         list_del_rcu(&chip->list);
1061         spin_unlock(&driver_lock);
1062         synchronize_rcu();
1063
1064         misc_deregister(&chip->vendor.miscdev);
1065         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1066         tpm_bios_log_teardown(chip->bios_dir);
1067
1068         /* write it this way to be explicit (chip->dev == dev) */
1069         put_device(chip->dev);
1070 }
1071 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1072
1073 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1074 #define SAVESTATE_RESULT_SIZE 10
1075
1076 static struct tpm_input_header savestate_header = {
1077         .tag = TPM_TAG_RQU_COMMAND,
1078         .length = cpu_to_be32(10),
1079         .ordinal = TPM_ORD_SAVESTATE
1080 };
1081
1082 /* Bug workaround - some TPM's don't flush the most
1083  * recently changed pcr on suspend, so force the flush
1084  * with an extend to the selected _unused_ non-volatile pcr.
1085  */
1086 static int tpm_suspend_pcr;
1087 static int __init tpm_suspend_setup(char *str)
1088 {
1089         get_option(&str, &tpm_suspend_pcr);
1090         return 1;
1091 }
1092 __setup("tpm_suspend_pcr=", tpm_suspend_setup);
1093
1094 /*
1095  * We are about to suspend. Save the TPM state
1096  * so that it can be restored.
1097  */
1098 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1099 {
1100         struct tpm_chip *chip = dev_get_drvdata(dev);
1101         struct tpm_cmd_t cmd;
1102         int rc;
1103
1104         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1105
1106         if (chip == NULL)
1107                 return -ENODEV;
1108
1109         /* for buggy tpm, flush pcrs with extend to selected dummy */
1110         if (tpm_suspend_pcr) {
1111                 cmd.header.in = pcrextend_header;
1112                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1113                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1114                        TPM_DIGEST_SIZE);
1115                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1116                                   "extending dummy pcr before suspend");
1117         }
1118
1119         /* now do the actual savestate */
1120         cmd.header.in = savestate_header;
1121         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1122                           "sending savestate before suspend");
1123         return rc;
1124 }
1125 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1126
1127 /*
1128  * Resume from a power safe. The BIOS already restored
1129  * the TPM state.
1130  */
1131 int tpm_pm_resume(struct device *dev)
1132 {
1133         struct tpm_chip *chip = dev_get_drvdata(dev);
1134
1135         if (chip == NULL)
1136                 return -ENODEV;
1137
1138         return 0;
1139 }
1140 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1141
1142 /* In case vendor provided release function, call it too.*/
1143
1144 void tpm_dev_vendor_release(struct tpm_chip *chip)
1145 {
1146         if (chip->vendor.release)
1147                 chip->vendor.release(chip->dev);
1148
1149         clear_bit(chip->dev_num, dev_mask);
1150         kfree(chip->vendor.miscdev.name);
1151 }
1152 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1153
1154
1155 /*
1156  * Once all references to platform device are down to 0,
1157  * release all allocated structures.
1158  */
1159 void tpm_dev_release(struct device *dev)
1160 {
1161         struct tpm_chip *chip = dev_get_drvdata(dev);
1162
1163         tpm_dev_vendor_release(chip);
1164
1165         chip->release(dev);
1166         kfree(chip);
1167 }
1168 EXPORT_SYMBOL_GPL(tpm_dev_release);
1169
1170 /*
1171  * Called from tpm_<specific>.c probe function only for devices 
1172  * the driver has determined it should claim.  Prior to calling
1173  * this function the specific probe function has called pci_enable_device
1174  * upon errant exit from this function specific probe function should call
1175  * pci_disable_device
1176  */
1177 struct tpm_chip *tpm_register_hardware(struct device *dev,
1178                                         const struct tpm_vendor_specific *entry)
1179 {
1180 #define DEVNAME_SIZE 7
1181
1182         char *devname;
1183         struct tpm_chip *chip;
1184
1185         /* Driver specific per-device data */
1186         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1187         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1188
1189         if (chip == NULL || devname == NULL)
1190                 goto out_free;
1191
1192         mutex_init(&chip->buffer_mutex);
1193         mutex_init(&chip->tpm_mutex);
1194         INIT_LIST_HEAD(&chip->list);
1195
1196         INIT_WORK(&chip->work, timeout_work);
1197
1198         setup_timer(&chip->user_read_timer, user_reader_timeout,
1199                         (unsigned long)chip);
1200
1201         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1202
1203         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1204
1205         if (chip->dev_num >= TPM_NUM_DEVICES) {
1206                 dev_err(dev, "No available tpm device numbers\n");
1207                 goto out_free;
1208         } else if (chip->dev_num == 0)
1209                 chip->vendor.miscdev.minor = TPM_MINOR;
1210         else
1211                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1212
1213         set_bit(chip->dev_num, dev_mask);
1214
1215         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1216         chip->vendor.miscdev.name = devname;
1217
1218         chip->vendor.miscdev.parent = dev;
1219         chip->dev = get_device(dev);
1220         chip->release = dev->release;
1221         dev->release = tpm_dev_release;
1222         dev_set_drvdata(dev, chip);
1223
1224         if (misc_register(&chip->vendor.miscdev)) {
1225                 dev_err(chip->dev,
1226                         "unable to misc_register %s, minor %d\n",
1227                         chip->vendor.miscdev.name,
1228                         chip->vendor.miscdev.minor);
1229                 put_device(chip->dev);
1230                 return NULL;
1231         }
1232
1233         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1234                 misc_deregister(&chip->vendor.miscdev);
1235                 put_device(chip->dev);
1236
1237                 return NULL;
1238         }
1239
1240         chip->bios_dir = tpm_bios_log_setup(devname);
1241
1242         /* Make chip available */
1243         spin_lock(&driver_lock);
1244         list_add_rcu(&chip->list, &tpm_chip_list);
1245         spin_unlock(&driver_lock);
1246
1247         return chip;
1248
1249 out_free:
1250         kfree(chip);
1251         kfree(devname);
1252         return NULL;
1253 }
1254 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1255
1256 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1257 MODULE_DESCRIPTION("TPM Driver");
1258 MODULE_VERSION("2.0");
1259 MODULE_LICENSE("GPL");