Merge branches 'stable/ia64', 'stable/blkfront-cleanup' and 'stable/cleanup' of git...
[pandora-kernel.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 /*
51  * Bug workaround - some TPM's don't flush the most
52  * recently changed pcr on suspend, so force the flush
53  * with an extend to the selected _unused_ non-volatile pcr.
54  */
55 static int tpm_suspend_pcr;
56 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
57 MODULE_PARM_DESC(suspend_pcr,
58                  "PCR to use for dummy writes to faciltate flush on suspend.");
59
60 static LIST_HEAD(tpm_chip_list);
61 static DEFINE_SPINLOCK(driver_lock);
62 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
63
64 /*
65  * Array with one entry per ordinal defining the maximum amount
66  * of time the chip could take to return the result.  The ordinal
67  * designation of short, medium or long is defined in a table in
68  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
69  * values of the SHORT, MEDIUM, and LONG durations are retrieved
70  * from the chip during initialization with a call to tpm_get_timeouts.
71  */
72 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
73         TPM_UNDEFINED,          /* 0 */
74         TPM_UNDEFINED,
75         TPM_UNDEFINED,
76         TPM_UNDEFINED,
77         TPM_UNDEFINED,
78         TPM_UNDEFINED,          /* 5 */
79         TPM_UNDEFINED,
80         TPM_UNDEFINED,
81         TPM_UNDEFINED,
82         TPM_UNDEFINED,
83         TPM_SHORT,              /* 10 */
84         TPM_SHORT,
85 };
86
87 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
88         TPM_UNDEFINED,          /* 0 */
89         TPM_UNDEFINED,
90         TPM_UNDEFINED,
91         TPM_UNDEFINED,
92         TPM_UNDEFINED,
93         TPM_UNDEFINED,          /* 5 */
94         TPM_UNDEFINED,
95         TPM_UNDEFINED,
96         TPM_UNDEFINED,
97         TPM_UNDEFINED,
98         TPM_SHORT,              /* 10 */
99         TPM_SHORT,
100         TPM_MEDIUM,
101         TPM_LONG,
102         TPM_LONG,
103         TPM_MEDIUM,             /* 15 */
104         TPM_SHORT,
105         TPM_SHORT,
106         TPM_MEDIUM,
107         TPM_LONG,
108         TPM_SHORT,              /* 20 */
109         TPM_SHORT,
110         TPM_MEDIUM,
111         TPM_MEDIUM,
112         TPM_MEDIUM,
113         TPM_SHORT,              /* 25 */
114         TPM_SHORT,
115         TPM_MEDIUM,
116         TPM_SHORT,
117         TPM_SHORT,
118         TPM_MEDIUM,             /* 30 */
119         TPM_LONG,
120         TPM_MEDIUM,
121         TPM_SHORT,
122         TPM_SHORT,
123         TPM_SHORT,              /* 35 */
124         TPM_MEDIUM,
125         TPM_MEDIUM,
126         TPM_UNDEFINED,
127         TPM_UNDEFINED,
128         TPM_MEDIUM,             /* 40 */
129         TPM_LONG,
130         TPM_MEDIUM,
131         TPM_SHORT,
132         TPM_SHORT,
133         TPM_SHORT,              /* 45 */
134         TPM_SHORT,
135         TPM_SHORT,
136         TPM_SHORT,
137         TPM_LONG,
138         TPM_MEDIUM,             /* 50 */
139         TPM_MEDIUM,
140         TPM_UNDEFINED,
141         TPM_UNDEFINED,
142         TPM_UNDEFINED,
143         TPM_UNDEFINED,          /* 55 */
144         TPM_UNDEFINED,
145         TPM_UNDEFINED,
146         TPM_UNDEFINED,
147         TPM_UNDEFINED,
148         TPM_MEDIUM,             /* 60 */
149         TPM_MEDIUM,
150         TPM_MEDIUM,
151         TPM_SHORT,
152         TPM_SHORT,
153         TPM_MEDIUM,             /* 65 */
154         TPM_UNDEFINED,
155         TPM_UNDEFINED,
156         TPM_UNDEFINED,
157         TPM_UNDEFINED,
158         TPM_SHORT,              /* 70 */
159         TPM_SHORT,
160         TPM_UNDEFINED,
161         TPM_UNDEFINED,
162         TPM_UNDEFINED,
163         TPM_UNDEFINED,          /* 75 */
164         TPM_UNDEFINED,
165         TPM_UNDEFINED,
166         TPM_UNDEFINED,
167         TPM_UNDEFINED,
168         TPM_LONG,               /* 80 */
169         TPM_UNDEFINED,
170         TPM_MEDIUM,
171         TPM_LONG,
172         TPM_SHORT,
173         TPM_UNDEFINED,          /* 85 */
174         TPM_UNDEFINED,
175         TPM_UNDEFINED,
176         TPM_UNDEFINED,
177         TPM_UNDEFINED,
178         TPM_SHORT,              /* 90 */
179         TPM_SHORT,
180         TPM_SHORT,
181         TPM_SHORT,
182         TPM_SHORT,
183         TPM_UNDEFINED,          /* 95 */
184         TPM_UNDEFINED,
185         TPM_UNDEFINED,
186         TPM_UNDEFINED,
187         TPM_UNDEFINED,
188         TPM_MEDIUM,             /* 100 */
189         TPM_SHORT,
190         TPM_SHORT,
191         TPM_UNDEFINED,
192         TPM_UNDEFINED,
193         TPM_UNDEFINED,          /* 105 */
194         TPM_UNDEFINED,
195         TPM_UNDEFINED,
196         TPM_UNDEFINED,
197         TPM_UNDEFINED,
198         TPM_SHORT,              /* 110 */
199         TPM_SHORT,
200         TPM_SHORT,
201         TPM_SHORT,
202         TPM_SHORT,
203         TPM_SHORT,              /* 115 */
204         TPM_SHORT,
205         TPM_SHORT,
206         TPM_UNDEFINED,
207         TPM_UNDEFINED,
208         TPM_LONG,               /* 120 */
209         TPM_LONG,
210         TPM_MEDIUM,
211         TPM_UNDEFINED,
212         TPM_SHORT,
213         TPM_SHORT,              /* 125 */
214         TPM_SHORT,
215         TPM_LONG,
216         TPM_SHORT,
217         TPM_SHORT,
218         TPM_SHORT,              /* 130 */
219         TPM_MEDIUM,
220         TPM_UNDEFINED,
221         TPM_SHORT,
222         TPM_MEDIUM,
223         TPM_UNDEFINED,          /* 135 */
224         TPM_UNDEFINED,
225         TPM_UNDEFINED,
226         TPM_UNDEFINED,
227         TPM_UNDEFINED,
228         TPM_SHORT,              /* 140 */
229         TPM_SHORT,
230         TPM_UNDEFINED,
231         TPM_UNDEFINED,
232         TPM_UNDEFINED,
233         TPM_UNDEFINED,          /* 145 */
234         TPM_UNDEFINED,
235         TPM_UNDEFINED,
236         TPM_UNDEFINED,
237         TPM_UNDEFINED,
238         TPM_SHORT,              /* 150 */
239         TPM_MEDIUM,
240         TPM_MEDIUM,
241         TPM_SHORT,
242         TPM_SHORT,
243         TPM_UNDEFINED,          /* 155 */
244         TPM_UNDEFINED,
245         TPM_UNDEFINED,
246         TPM_UNDEFINED,
247         TPM_UNDEFINED,
248         TPM_SHORT,              /* 160 */
249         TPM_SHORT,
250         TPM_SHORT,
251         TPM_SHORT,
252         TPM_UNDEFINED,
253         TPM_UNDEFINED,          /* 165 */
254         TPM_UNDEFINED,
255         TPM_UNDEFINED,
256         TPM_UNDEFINED,
257         TPM_UNDEFINED,
258         TPM_LONG,               /* 170 */
259         TPM_UNDEFINED,
260         TPM_UNDEFINED,
261         TPM_UNDEFINED,
262         TPM_UNDEFINED,
263         TPM_UNDEFINED,          /* 175 */
264         TPM_UNDEFINED,
265         TPM_UNDEFINED,
266         TPM_UNDEFINED,
267         TPM_UNDEFINED,
268         TPM_MEDIUM,             /* 180 */
269         TPM_SHORT,
270         TPM_MEDIUM,
271         TPM_MEDIUM,
272         TPM_MEDIUM,
273         TPM_MEDIUM,             /* 185 */
274         TPM_SHORT,
275         TPM_UNDEFINED,
276         TPM_UNDEFINED,
277         TPM_UNDEFINED,
278         TPM_UNDEFINED,          /* 190 */
279         TPM_UNDEFINED,
280         TPM_UNDEFINED,
281         TPM_UNDEFINED,
282         TPM_UNDEFINED,
283         TPM_UNDEFINED,          /* 195 */
284         TPM_UNDEFINED,
285         TPM_UNDEFINED,
286         TPM_UNDEFINED,
287         TPM_UNDEFINED,
288         TPM_SHORT,              /* 200 */
289         TPM_UNDEFINED,
290         TPM_UNDEFINED,
291         TPM_UNDEFINED,
292         TPM_SHORT,
293         TPM_SHORT,              /* 205 */
294         TPM_SHORT,
295         TPM_SHORT,
296         TPM_SHORT,
297         TPM_SHORT,
298         TPM_MEDIUM,             /* 210 */
299         TPM_UNDEFINED,
300         TPM_MEDIUM,
301         TPM_MEDIUM,
302         TPM_MEDIUM,
303         TPM_UNDEFINED,          /* 215 */
304         TPM_MEDIUM,
305         TPM_UNDEFINED,
306         TPM_UNDEFINED,
307         TPM_SHORT,
308         TPM_SHORT,              /* 220 */
309         TPM_SHORT,
310         TPM_SHORT,
311         TPM_SHORT,
312         TPM_SHORT,
313         TPM_UNDEFINED,          /* 225 */
314         TPM_UNDEFINED,
315         TPM_UNDEFINED,
316         TPM_UNDEFINED,
317         TPM_UNDEFINED,
318         TPM_SHORT,              /* 230 */
319         TPM_LONG,
320         TPM_MEDIUM,
321         TPM_UNDEFINED,
322         TPM_UNDEFINED,
323         TPM_UNDEFINED,          /* 235 */
324         TPM_UNDEFINED,
325         TPM_UNDEFINED,
326         TPM_UNDEFINED,
327         TPM_UNDEFINED,
328         TPM_SHORT,              /* 240 */
329         TPM_UNDEFINED,
330         TPM_MEDIUM,
331 };
332
333 static void user_reader_timeout(unsigned long ptr)
334 {
335         struct tpm_chip *chip = (struct tpm_chip *) ptr;
336
337         schedule_work(&chip->work);
338 }
339
340 static void timeout_work(struct work_struct *work)
341 {
342         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
343
344         mutex_lock(&chip->buffer_mutex);
345         atomic_set(&chip->data_pending, 0);
346         memset(chip->data_buffer, 0, TPM_BUFSIZE);
347         mutex_unlock(&chip->buffer_mutex);
348 }
349
350 /*
351  * Returns max number of jiffies to wait
352  */
353 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
354                                            u32 ordinal)
355 {
356         int duration_idx = TPM_UNDEFINED;
357         int duration = 0;
358
359         if (ordinal < TPM_MAX_ORDINAL)
360                 duration_idx = tpm_ordinal_duration[ordinal];
361         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
362                  TPM_MAX_PROTECTED_ORDINAL)
363                 duration_idx =
364                     tpm_protected_ordinal_duration[ordinal &
365                                                    TPM_PROTECTED_ORDINAL_MASK];
366
367         if (duration_idx != TPM_UNDEFINED)
368                 duration = chip->vendor.duration[duration_idx];
369         if (duration <= 0)
370                 return 2 * 60 * HZ;
371         else
372                 return duration;
373 }
374 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
375
376 /*
377  * Internal kernel interface to transmit TPM commands
378  */
379 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
380                             size_t bufsiz)
381 {
382         ssize_t rc;
383         u32 count, ordinal;
384         unsigned long stop;
385
386         count = be32_to_cpu(*((__be32 *) (buf + 2)));
387         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
388         if (count == 0)
389                 return -ENODATA;
390         if (count > bufsiz) {
391                 dev_err(chip->dev,
392                         "invalid count value %x %zx \n", count, bufsiz);
393                 return -E2BIG;
394         }
395
396         mutex_lock(&chip->tpm_mutex);
397
398         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
399                 dev_err(chip->dev,
400                         "tpm_transmit: tpm_send: error %zd\n", rc);
401                 goto out;
402         }
403
404         if (chip->vendor.irq)
405                 goto out_recv;
406
407         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
408         do {
409                 u8 status = chip->vendor.status(chip);
410                 if ((status & chip->vendor.req_complete_mask) ==
411                     chip->vendor.req_complete_val)
412                         goto out_recv;
413
414                 if ((status == chip->vendor.req_canceled)) {
415                         dev_err(chip->dev, "Operation Canceled\n");
416                         rc = -ECANCELED;
417                         goto out;
418                 }
419
420                 msleep(TPM_TIMEOUT);    /* CHECK */
421                 rmb();
422         } while (time_before(jiffies, stop));
423
424         chip->vendor.cancel(chip);
425         dev_err(chip->dev, "Operation Timed out\n");
426         rc = -ETIME;
427         goto out;
428
429 out_recv:
430         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
431         if (rc < 0)
432                 dev_err(chip->dev,
433                         "tpm_transmit: tpm_recv: error %zd\n", rc);
434 out:
435         mutex_unlock(&chip->tpm_mutex);
436         return rc;
437 }
438
439 #define TPM_DIGEST_SIZE 20
440 #define TPM_ERROR_SIZE 10
441 #define TPM_RET_CODE_IDX 6
442
443 enum tpm_capabilities {
444         TPM_CAP_FLAG = cpu_to_be32(4),
445         TPM_CAP_PROP = cpu_to_be32(5),
446         CAP_VERSION_1_1 = cpu_to_be32(0x06),
447         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
448 };
449
450 enum tpm_sub_capabilities {
451         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
452         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
453         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
454         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
455         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
456         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
457         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
458
459 };
460
461 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
462                             int len, const char *desc)
463 {
464         int err;
465
466         len = tpm_transmit(chip,(u8 *) cmd, len);
467         if (len <  0)
468                 return len;
469         if (len == TPM_ERROR_SIZE) {
470                 err = be32_to_cpu(cmd->header.out.return_code);
471                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
472                 return err;
473         }
474         return 0;
475 }
476
477 #define TPM_INTERNAL_RESULT_SIZE 200
478 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
479 #define TPM_ORD_GET_CAP cpu_to_be32(101)
480
481 static const struct tpm_input_header tpm_getcap_header = {
482         .tag = TPM_TAG_RQU_COMMAND,
483         .length = cpu_to_be32(22),
484         .ordinal = TPM_ORD_GET_CAP
485 };
486
487 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
488                    const char *desc)
489 {
490         struct tpm_cmd_t tpm_cmd;
491         int rc;
492         struct tpm_chip *chip = dev_get_drvdata(dev);
493
494         tpm_cmd.header.in = tpm_getcap_header;
495         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
496                 tpm_cmd.params.getcap_in.cap = subcap_id;
497                 /*subcap field not necessary */
498                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
499                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
500         } else {
501                 if (subcap_id == TPM_CAP_FLAG_PERM ||
502                     subcap_id == TPM_CAP_FLAG_VOL)
503                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
504                 else
505                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
506                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
507                 tpm_cmd.params.getcap_in.subcap = subcap_id;
508         }
509         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
510         if (!rc)
511                 *cap = tpm_cmd.params.getcap_out.cap;
512         return rc;
513 }
514
515 void tpm_gen_interrupt(struct tpm_chip *chip)
516 {
517         struct  tpm_cmd_t tpm_cmd;
518         ssize_t rc;
519
520         tpm_cmd.header.in = tpm_getcap_header;
521         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
522         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
523         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
524
525         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
526                         "attempting to determine the timeouts");
527 }
528 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
529
530 void tpm_get_timeouts(struct tpm_chip *chip)
531 {
532         struct tpm_cmd_t tpm_cmd;
533         struct timeout_t *timeout_cap;
534         struct duration_t *duration_cap;
535         ssize_t rc;
536         u32 timeout;
537
538         tpm_cmd.header.in = tpm_getcap_header;
539         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
540         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
541         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
542
543         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
544                         "attempting to determine the timeouts");
545         if (rc)
546                 goto duration;
547
548         if (be32_to_cpu(tpm_cmd.header.out.length)
549             != 4 * sizeof(u32))
550                 goto duration;
551
552         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
553         /* Don't overwrite default if value is 0 */
554         timeout = be32_to_cpu(timeout_cap->a);
555         if (timeout)
556                 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
557         timeout = be32_to_cpu(timeout_cap->b);
558         if (timeout)
559                 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
560         timeout = be32_to_cpu(timeout_cap->c);
561         if (timeout)
562                 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
563         timeout = be32_to_cpu(timeout_cap->d);
564         if (timeout)
565                 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
566
567 duration:
568         tpm_cmd.header.in = tpm_getcap_header;
569         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
570         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
571         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
572
573         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
574                         "attempting to determine the durations");
575         if (rc)
576                 return;
577
578         if (be32_to_cpu(tpm_cmd.header.out.return_code)
579             != 3 * sizeof(u32))
580                 return;
581         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
582         chip->vendor.duration[TPM_SHORT] =
583             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
584         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
585          * value wrong and apparently reports msecs rather than usecs. So we
586          * fix up the resulting too-small TPM_SHORT value to make things work.
587          */
588         if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
589                 chip->vendor.duration[TPM_SHORT] = HZ;
590
591         chip->vendor.duration[TPM_MEDIUM] =
592             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
593         chip->vendor.duration[TPM_LONG] =
594             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
595 }
596 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
597
598 void tpm_continue_selftest(struct tpm_chip *chip)
599 {
600         u8 data[] = {
601                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
602                 0, 0, 0, 10,            /* length */
603                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
604         };
605
606         tpm_transmit(chip, data, sizeof(data));
607 }
608 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
609
610 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
611                         char *buf)
612 {
613         cap_t cap;
614         ssize_t rc;
615
616         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
617                          "attempting to determine the permanent enabled state");
618         if (rc)
619                 return 0;
620
621         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
622         return rc;
623 }
624 EXPORT_SYMBOL_GPL(tpm_show_enabled);
625
626 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
627                         char *buf)
628 {
629         cap_t cap;
630         ssize_t rc;
631
632         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
633                          "attempting to determine the permanent active state");
634         if (rc)
635                 return 0;
636
637         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
638         return rc;
639 }
640 EXPORT_SYMBOL_GPL(tpm_show_active);
641
642 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
643                         char *buf)
644 {
645         cap_t cap;
646         ssize_t rc;
647
648         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
649                          "attempting to determine the owner state");
650         if (rc)
651                 return 0;
652
653         rc = sprintf(buf, "%d\n", cap.owned);
654         return rc;
655 }
656 EXPORT_SYMBOL_GPL(tpm_show_owned);
657
658 ssize_t tpm_show_temp_deactivated(struct device * dev,
659                                 struct device_attribute * attr, char *buf)
660 {
661         cap_t cap;
662         ssize_t rc;
663
664         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
665                          "attempting to determine the temporary state");
666         if (rc)
667                 return 0;
668
669         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
670         return rc;
671 }
672 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
673
674 /*
675  * tpm_chip_find_get - return tpm_chip for given chip number
676  */
677 static struct tpm_chip *tpm_chip_find_get(int chip_num)
678 {
679         struct tpm_chip *pos, *chip = NULL;
680
681         rcu_read_lock();
682         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
683                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
684                         continue;
685
686                 if (try_module_get(pos->dev->driver->owner)) {
687                         chip = pos;
688                         break;
689                 }
690         }
691         rcu_read_unlock();
692         return chip;
693 }
694
695 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
696 #define READ_PCR_RESULT_SIZE 30
697 static struct tpm_input_header pcrread_header = {
698         .tag = TPM_TAG_RQU_COMMAND,
699         .length = cpu_to_be32(14),
700         .ordinal = TPM_ORDINAL_PCRREAD
701 };
702
703 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
704 {
705         int rc;
706         struct tpm_cmd_t cmd;
707
708         cmd.header.in = pcrread_header;
709         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
710         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
711                           "attempting to read a pcr value");
712
713         if (rc == 0)
714                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
715                        TPM_DIGEST_SIZE);
716         return rc;
717 }
718
719 /**
720  * tpm_pcr_read - read a pcr value
721  * @chip_num:   tpm idx # or ANY
722  * @pcr_idx:    pcr idx to retrieve
723  * @res_buf:    TPM_PCR value
724  *              size of res_buf is 20 bytes (or NULL if you don't care)
725  *
726  * The TPM driver should be built-in, but for whatever reason it
727  * isn't, protect against the chip disappearing, by incrementing
728  * the module usage count.
729  */
730 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
731 {
732         struct tpm_chip *chip;
733         int rc;
734
735         chip = tpm_chip_find_get(chip_num);
736         if (chip == NULL)
737                 return -ENODEV;
738         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
739         tpm_chip_put(chip);
740         return rc;
741 }
742 EXPORT_SYMBOL_GPL(tpm_pcr_read);
743
744 /**
745  * tpm_pcr_extend - extend pcr value with hash
746  * @chip_num:   tpm idx # or AN&
747  * @pcr_idx:    pcr idx to extend
748  * @hash:       hash value used to extend pcr value
749  *
750  * The TPM driver should be built-in, but for whatever reason it
751  * isn't, protect against the chip disappearing, by incrementing
752  * the module usage count.
753  */
754 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
755 #define EXTEND_PCR_RESULT_SIZE 34
756 static struct tpm_input_header pcrextend_header = {
757         .tag = TPM_TAG_RQU_COMMAND,
758         .length = cpu_to_be32(34),
759         .ordinal = TPM_ORD_PCR_EXTEND
760 };
761
762 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
763 {
764         struct tpm_cmd_t cmd;
765         int rc;
766         struct tpm_chip *chip;
767
768         chip = tpm_chip_find_get(chip_num);
769         if (chip == NULL)
770                 return -ENODEV;
771
772         cmd.header.in = pcrextend_header;
773         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
774         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
775         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
776                           "attempting extend a PCR value");
777
778         tpm_chip_put(chip);
779         return rc;
780 }
781 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
782
783 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
784 {
785         struct tpm_chip *chip;
786         int rc;
787
788         chip = tpm_chip_find_get(chip_num);
789         if (chip == NULL)
790                 return -ENODEV;
791
792         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
793
794         tpm_chip_put(chip);
795         return rc;
796 }
797 EXPORT_SYMBOL_GPL(tpm_send);
798
799 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
800                       char *buf)
801 {
802         cap_t cap;
803         u8 digest[TPM_DIGEST_SIZE];
804         ssize_t rc;
805         int i, j, num_pcrs;
806         char *str = buf;
807         struct tpm_chip *chip = dev_get_drvdata(dev);
808
809         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
810                         "attempting to determine the number of PCRS");
811         if (rc)
812                 return 0;
813
814         num_pcrs = be32_to_cpu(cap.num_pcrs);
815         for (i = 0; i < num_pcrs; i++) {
816                 rc = __tpm_pcr_read(chip, i, digest);
817                 if (rc)
818                         break;
819                 str += sprintf(str, "PCR-%02d: ", i);
820                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
821                         str += sprintf(str, "%02X ", digest[j]);
822                 str += sprintf(str, "\n");
823         }
824         return str - buf;
825 }
826 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
827
828 #define  READ_PUBEK_RESULT_SIZE 314
829 #define TPM_ORD_READPUBEK cpu_to_be32(124)
830 struct tpm_input_header tpm_readpubek_header = {
831         .tag = TPM_TAG_RQU_COMMAND,
832         .length = cpu_to_be32(30),
833         .ordinal = TPM_ORD_READPUBEK
834 };
835
836 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
837                        char *buf)
838 {
839         u8 *data;
840         struct tpm_cmd_t tpm_cmd;
841         ssize_t err;
842         int i, rc;
843         char *str = buf;
844
845         struct tpm_chip *chip = dev_get_drvdata(dev);
846
847         tpm_cmd.header.in = tpm_readpubek_header;
848         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
849                         "attempting to read the PUBEK");
850         if (err)
851                 goto out;
852
853         /* 
854            ignore header 10 bytes
855            algorithm 32 bits (1 == RSA )
856            encscheme 16 bits
857            sigscheme 16 bits
858            parameters (RSA 12->bytes: keybit, #primes, expbit)  
859            keylenbytes 32 bits
860            256 byte modulus
861            ignore checksum 20 bytes
862          */
863         data = tpm_cmd.params.readpubek_out_buffer;
864         str +=
865             sprintf(str,
866                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
867                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
868                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
869                     "Modulus length: %d\nModulus: \n",
870                     data[10], data[11], data[12], data[13], data[14],
871                     data[15], data[16], data[17], data[22], data[23],
872                     data[24], data[25], data[26], data[27], data[28],
873                     data[29], data[30], data[31], data[32], data[33],
874                     be32_to_cpu(*((__be32 *) (data + 34))));
875
876         for (i = 0; i < 256; i++) {
877                 str += sprintf(str, "%02X ", data[i + 38]);
878                 if ((i + 1) % 16 == 0)
879                         str += sprintf(str, "\n");
880         }
881 out:
882         rc = str - buf;
883         return rc;
884 }
885 EXPORT_SYMBOL_GPL(tpm_show_pubek);
886
887
888 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
889                       char *buf)
890 {
891         cap_t cap;
892         ssize_t rc;
893         char *str = buf;
894
895         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
896                         "attempting to determine the manufacturer");
897         if (rc)
898                 return 0;
899         str += sprintf(str, "Manufacturer: 0x%x\n",
900                        be32_to_cpu(cap.manufacturer_id));
901
902         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
903                         "attempting to determine the 1.1 version");
904         if (rc)
905                 return 0;
906         str += sprintf(str,
907                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
908                        cap.tpm_version.Major, cap.tpm_version.Minor,
909                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
910         return str - buf;
911 }
912 EXPORT_SYMBOL_GPL(tpm_show_caps);
913
914 ssize_t tpm_show_caps_1_2(struct device * dev,
915                           struct device_attribute * attr, char *buf)
916 {
917         cap_t cap;
918         ssize_t rc;
919         char *str = buf;
920
921         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
922                         "attempting to determine the manufacturer");
923         if (rc)
924                 return 0;
925         str += sprintf(str, "Manufacturer: 0x%x\n",
926                        be32_to_cpu(cap.manufacturer_id));
927         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
928                          "attempting to determine the 1.2 version");
929         if (rc)
930                 return 0;
931         str += sprintf(str,
932                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
933                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
934                        cap.tpm_version_1_2.revMajor,
935                        cap.tpm_version_1_2.revMinor);
936         return str - buf;
937 }
938 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
939
940 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
941                         const char *buf, size_t count)
942 {
943         struct tpm_chip *chip = dev_get_drvdata(dev);
944         if (chip == NULL)
945                 return 0;
946
947         chip->vendor.cancel(chip);
948         return count;
949 }
950 EXPORT_SYMBOL_GPL(tpm_store_cancel);
951
952 /*
953  * Device file system interface to the TPM
954  *
955  * It's assured that the chip will be opened just once,
956  * by the check of is_open variable, which is protected
957  * by driver_lock.
958  */
959 int tpm_open(struct inode *inode, struct file *file)
960 {
961         int minor = iminor(inode);
962         struct tpm_chip *chip = NULL, *pos;
963
964         rcu_read_lock();
965         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
966                 if (pos->vendor.miscdev.minor == minor) {
967                         chip = pos;
968                         get_device(chip->dev);
969                         break;
970                 }
971         }
972         rcu_read_unlock();
973
974         if (!chip)
975                 return -ENODEV;
976
977         if (test_and_set_bit(0, &chip->is_open)) {
978                 dev_dbg(chip->dev, "Another process owns this TPM\n");
979                 put_device(chip->dev);
980                 return -EBUSY;
981         }
982
983         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
984         if (chip->data_buffer == NULL) {
985                 clear_bit(0, &chip->is_open);
986                 put_device(chip->dev);
987                 return -ENOMEM;
988         }
989
990         atomic_set(&chip->data_pending, 0);
991
992         file->private_data = chip;
993         return 0;
994 }
995 EXPORT_SYMBOL_GPL(tpm_open);
996
997 /*
998  * Called on file close
999  */
1000 int tpm_release(struct inode *inode, struct file *file)
1001 {
1002         struct tpm_chip *chip = file->private_data;
1003
1004         del_singleshot_timer_sync(&chip->user_read_timer);
1005         flush_work_sync(&chip->work);
1006         file->private_data = NULL;
1007         atomic_set(&chip->data_pending, 0);
1008         kfree(chip->data_buffer);
1009         clear_bit(0, &chip->is_open);
1010         put_device(chip->dev);
1011         return 0;
1012 }
1013 EXPORT_SYMBOL_GPL(tpm_release);
1014
1015 ssize_t tpm_write(struct file *file, const char __user *buf,
1016                   size_t size, loff_t *off)
1017 {
1018         struct tpm_chip *chip = file->private_data;
1019         size_t in_size = size, out_size;
1020
1021         /* cannot perform a write until the read has cleared
1022            either via tpm_read or a user_read_timer timeout */
1023         while (atomic_read(&chip->data_pending) != 0)
1024                 msleep(TPM_TIMEOUT);
1025
1026         mutex_lock(&chip->buffer_mutex);
1027
1028         if (in_size > TPM_BUFSIZE)
1029                 in_size = TPM_BUFSIZE;
1030
1031         if (copy_from_user
1032             (chip->data_buffer, (void __user *) buf, in_size)) {
1033                 mutex_unlock(&chip->buffer_mutex);
1034                 return -EFAULT;
1035         }
1036
1037         /* atomic tpm command send and result receive */
1038         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1039
1040         atomic_set(&chip->data_pending, out_size);
1041         mutex_unlock(&chip->buffer_mutex);
1042
1043         /* Set a timeout by which the reader must come claim the result */
1044         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1045
1046         return in_size;
1047 }
1048 EXPORT_SYMBOL_GPL(tpm_write);
1049
1050 ssize_t tpm_read(struct file *file, char __user *buf,
1051                  size_t size, loff_t *off)
1052 {
1053         struct tpm_chip *chip = file->private_data;
1054         ssize_t ret_size;
1055
1056         del_singleshot_timer_sync(&chip->user_read_timer);
1057         flush_work_sync(&chip->work);
1058         ret_size = atomic_read(&chip->data_pending);
1059         atomic_set(&chip->data_pending, 0);
1060         if (ret_size > 0) {     /* relay data */
1061                 if (size < ret_size)
1062                         ret_size = size;
1063
1064                 mutex_lock(&chip->buffer_mutex);
1065                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1066                         ret_size = -EFAULT;
1067                 mutex_unlock(&chip->buffer_mutex);
1068         }
1069
1070         return ret_size;
1071 }
1072 EXPORT_SYMBOL_GPL(tpm_read);
1073
1074 void tpm_remove_hardware(struct device *dev)
1075 {
1076         struct tpm_chip *chip = dev_get_drvdata(dev);
1077
1078         if (chip == NULL) {
1079                 dev_err(dev, "No device data found\n");
1080                 return;
1081         }
1082
1083         spin_lock(&driver_lock);
1084         list_del_rcu(&chip->list);
1085         spin_unlock(&driver_lock);
1086         synchronize_rcu();
1087
1088         misc_deregister(&chip->vendor.miscdev);
1089         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1090         tpm_bios_log_teardown(chip->bios_dir);
1091
1092         /* write it this way to be explicit (chip->dev == dev) */
1093         put_device(chip->dev);
1094 }
1095 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1096
1097 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1098 #define SAVESTATE_RESULT_SIZE 10
1099
1100 static struct tpm_input_header savestate_header = {
1101         .tag = TPM_TAG_RQU_COMMAND,
1102         .length = cpu_to_be32(10),
1103         .ordinal = TPM_ORD_SAVESTATE
1104 };
1105
1106 /*
1107  * We are about to suspend. Save the TPM state
1108  * so that it can be restored.
1109  */
1110 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1111 {
1112         struct tpm_chip *chip = dev_get_drvdata(dev);
1113         struct tpm_cmd_t cmd;
1114         int rc;
1115
1116         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1117
1118         if (chip == NULL)
1119                 return -ENODEV;
1120
1121         /* for buggy tpm, flush pcrs with extend to selected dummy */
1122         if (tpm_suspend_pcr) {
1123                 cmd.header.in = pcrextend_header;
1124                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1125                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1126                        TPM_DIGEST_SIZE);
1127                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1128                                   "extending dummy pcr before suspend");
1129         }
1130
1131         /* now do the actual savestate */
1132         cmd.header.in = savestate_header;
1133         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1134                           "sending savestate before suspend");
1135         return rc;
1136 }
1137 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1138
1139 /*
1140  * Resume from a power safe. The BIOS already restored
1141  * the TPM state.
1142  */
1143 int tpm_pm_resume(struct device *dev)
1144 {
1145         struct tpm_chip *chip = dev_get_drvdata(dev);
1146
1147         if (chip == NULL)
1148                 return -ENODEV;
1149
1150         return 0;
1151 }
1152 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1153
1154 /* In case vendor provided release function, call it too.*/
1155
1156 void tpm_dev_vendor_release(struct tpm_chip *chip)
1157 {
1158         if (chip->vendor.release)
1159                 chip->vendor.release(chip->dev);
1160
1161         clear_bit(chip->dev_num, dev_mask);
1162         kfree(chip->vendor.miscdev.name);
1163 }
1164 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1165
1166
1167 /*
1168  * Once all references to platform device are down to 0,
1169  * release all allocated structures.
1170  */
1171 void tpm_dev_release(struct device *dev)
1172 {
1173         struct tpm_chip *chip = dev_get_drvdata(dev);
1174
1175         tpm_dev_vendor_release(chip);
1176
1177         chip->release(dev);
1178         kfree(chip);
1179 }
1180 EXPORT_SYMBOL_GPL(tpm_dev_release);
1181
1182 /*
1183  * Called from tpm_<specific>.c probe function only for devices 
1184  * the driver has determined it should claim.  Prior to calling
1185  * this function the specific probe function has called pci_enable_device
1186  * upon errant exit from this function specific probe function should call
1187  * pci_disable_device
1188  */
1189 struct tpm_chip *tpm_register_hardware(struct device *dev,
1190                                         const struct tpm_vendor_specific *entry)
1191 {
1192 #define DEVNAME_SIZE 7
1193
1194         char *devname;
1195         struct tpm_chip *chip;
1196
1197         /* Driver specific per-device data */
1198         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1199         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1200
1201         if (chip == NULL || devname == NULL)
1202                 goto out_free;
1203
1204         mutex_init(&chip->buffer_mutex);
1205         mutex_init(&chip->tpm_mutex);
1206         INIT_LIST_HEAD(&chip->list);
1207
1208         INIT_WORK(&chip->work, timeout_work);
1209
1210         setup_timer(&chip->user_read_timer, user_reader_timeout,
1211                         (unsigned long)chip);
1212
1213         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1214
1215         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1216
1217         if (chip->dev_num >= TPM_NUM_DEVICES) {
1218                 dev_err(dev, "No available tpm device numbers\n");
1219                 goto out_free;
1220         } else if (chip->dev_num == 0)
1221                 chip->vendor.miscdev.minor = TPM_MINOR;
1222         else
1223                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1224
1225         set_bit(chip->dev_num, dev_mask);
1226
1227         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1228         chip->vendor.miscdev.name = devname;
1229
1230         chip->vendor.miscdev.parent = dev;
1231         chip->dev = get_device(dev);
1232         chip->release = dev->release;
1233         dev->release = tpm_dev_release;
1234         dev_set_drvdata(dev, chip);
1235
1236         if (misc_register(&chip->vendor.miscdev)) {
1237                 dev_err(chip->dev,
1238                         "unable to misc_register %s, minor %d\n",
1239                         chip->vendor.miscdev.name,
1240                         chip->vendor.miscdev.minor);
1241                 put_device(chip->dev);
1242                 return NULL;
1243         }
1244
1245         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1246                 misc_deregister(&chip->vendor.miscdev);
1247                 put_device(chip->dev);
1248
1249                 return NULL;
1250         }
1251
1252         chip->bios_dir = tpm_bios_log_setup(devname);
1253
1254         /* Make chip available */
1255         spin_lock(&driver_lock);
1256         list_add_rcu(&chip->list, &tpm_chip_list);
1257         spin_unlock(&driver_lock);
1258
1259         return chip;
1260
1261 out_free:
1262         kfree(chip);
1263         kfree(devname);
1264         return NULL;
1265 }
1266 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1267
1268 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1269 MODULE_DESCRIPTION("TPM Driver");
1270 MODULE_VERSION("2.0");
1271 MODULE_LICENSE("GPL");