Revert "tpm_tis: Use timeouts returned from TPM"
[linux-2.6.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 is 0, it's because chip->vendor.duration wasn't */
370                 /* filled yet, so we set the lowest timeout just to give enough */
371                 /* time for tpm_get_timeouts() to succeed */
372                 return (duration <= 0 ? HZ : duration);
373         } else
374                 return 2 * 60 * HZ;
375 }
376 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
377
378 /*
379  * Internal kernel interface to transmit TPM commands
380  */
381 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
382                             size_t bufsiz)
383 {
384         ssize_t rc;
385         u32 count, ordinal;
386         unsigned long stop;
387
388         count = be32_to_cpu(*((__be32 *) (buf + 2)));
389         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
390         if (count == 0)
391                 return -ENODATA;
392         if (count > bufsiz) {
393                 dev_err(chip->dev,
394                         "invalid count value %x %zx \n", count, bufsiz);
395                 return -E2BIG;
396         }
397
398         mutex_lock(&chip->tpm_mutex);
399
400         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
401                 dev_err(chip->dev,
402                         "tpm_transmit: tpm_send: error %zd\n", rc);
403                 goto out;
404         }
405
406         if (chip->vendor.irq)
407                 goto out_recv;
408
409         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
410         do {
411                 u8 status = chip->vendor.status(chip);
412                 if ((status & chip->vendor.req_complete_mask) ==
413                     chip->vendor.req_complete_val)
414                         goto out_recv;
415
416                 if ((status == chip->vendor.req_canceled)) {
417                         dev_err(chip->dev, "Operation Canceled\n");
418                         rc = -ECANCELED;
419                         goto out;
420                 }
421
422                 msleep(TPM_TIMEOUT);    /* CHECK */
423                 rmb();
424         } while (time_before(jiffies, stop));
425
426         chip->vendor.cancel(chip);
427         dev_err(chip->dev, "Operation Timed out\n");
428         rc = -ETIME;
429         goto out;
430
431 out_recv:
432         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
433         if (rc < 0)
434                 dev_err(chip->dev,
435                         "tpm_transmit: tpm_recv: error %zd\n", rc);
436 out:
437         mutex_unlock(&chip->tpm_mutex);
438         return rc;
439 }
440
441 #define TPM_DIGEST_SIZE 20
442 #define TPM_ERROR_SIZE 10
443 #define TPM_RET_CODE_IDX 6
444
445 enum tpm_capabilities {
446         TPM_CAP_FLAG = cpu_to_be32(4),
447         TPM_CAP_PROP = cpu_to_be32(5),
448         CAP_VERSION_1_1 = cpu_to_be32(0x06),
449         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
450 };
451
452 enum tpm_sub_capabilities {
453         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
454         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
455         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
456         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
457         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
458         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
459         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
460
461 };
462
463 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
464                             int len, const char *desc)
465 {
466         int err;
467
468         len = tpm_transmit(chip,(u8 *) cmd, len);
469         if (len <  0)
470                 return len;
471         if (len == TPM_ERROR_SIZE) {
472                 err = be32_to_cpu(cmd->header.out.return_code);
473                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
474                 return err;
475         }
476         return 0;
477 }
478
479 #define TPM_INTERNAL_RESULT_SIZE 200
480 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
481 #define TPM_ORD_GET_CAP cpu_to_be32(101)
482
483 static const struct tpm_input_header tpm_getcap_header = {
484         .tag = TPM_TAG_RQU_COMMAND,
485         .length = cpu_to_be32(22),
486         .ordinal = TPM_ORD_GET_CAP
487 };
488
489 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
490                    const char *desc)
491 {
492         struct tpm_cmd_t tpm_cmd;
493         int rc;
494         struct tpm_chip *chip = dev_get_drvdata(dev);
495
496         tpm_cmd.header.in = tpm_getcap_header;
497         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
498                 tpm_cmd.params.getcap_in.cap = subcap_id;
499                 /*subcap field not necessary */
500                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
501                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
502         } else {
503                 if (subcap_id == TPM_CAP_FLAG_PERM ||
504                     subcap_id == TPM_CAP_FLAG_VOL)
505                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
506                 else
507                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
508                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
509                 tpm_cmd.params.getcap_in.subcap = subcap_id;
510         }
511         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
512         if (!rc)
513                 *cap = tpm_cmd.params.getcap_out.cap;
514         return rc;
515 }
516
517 void tpm_gen_interrupt(struct tpm_chip *chip)
518 {
519         struct  tpm_cmd_t tpm_cmd;
520         ssize_t rc;
521
522         tpm_cmd.header.in = tpm_getcap_header;
523         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
524         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
525         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
526
527         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
528                         "attempting to determine the timeouts");
529 }
530 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
531
532 void tpm_get_timeouts(struct tpm_chip *chip)
533 {
534         struct tpm_cmd_t tpm_cmd;
535         struct timeout_t *timeout_cap;
536         struct duration_t *duration_cap;
537         ssize_t rc;
538         u32 timeout;
539
540         tpm_cmd.header.in = tpm_getcap_header;
541         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
542         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
543         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
544
545         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
546                         "attempting to determine the timeouts");
547         if (rc)
548                 goto duration;
549
550         if (be32_to_cpu(tpm_cmd.header.out.length)
551             != 4 * sizeof(u32))
552                 goto duration;
553
554         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
555         /* Don't overwrite default if value is 0 */
556         timeout = be32_to_cpu(timeout_cap->a);
557         if (timeout)
558                 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
559         timeout = be32_to_cpu(timeout_cap->b);
560         if (timeout)
561                 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
562         timeout = be32_to_cpu(timeout_cap->c);
563         if (timeout)
564                 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
565         timeout = be32_to_cpu(timeout_cap->d);
566         if (timeout)
567                 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
568
569 duration:
570         tpm_cmd.header.in = tpm_getcap_header;
571         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
572         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
573         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
574
575         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
576                         "attempting to determine the durations");
577         if (rc)
578                 return;
579
580         if (be32_to_cpu(tpm_cmd.header.out.return_code)
581             != 3 * sizeof(u32))
582                 return;
583         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
584         chip->vendor.duration[TPM_SHORT] =
585             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
586         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
587          * value wrong and apparently reports msecs rather than usecs. So we
588          * fix up the resulting too-small TPM_SHORT value to make things work.
589          */
590         if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
591                 chip->vendor.duration[TPM_SHORT] = HZ;
592
593         chip->vendor.duration[TPM_MEDIUM] =
594             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
595         chip->vendor.duration[TPM_LONG] =
596             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
597 }
598 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
599
600 void tpm_continue_selftest(struct tpm_chip *chip)
601 {
602         u8 data[] = {
603                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
604                 0, 0, 0, 10,            /* length */
605                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
606         };
607
608         tpm_transmit(chip, data, sizeof(data));
609 }
610 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
611
612 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
613                         char *buf)
614 {
615         cap_t cap;
616         ssize_t rc;
617
618         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
619                          "attempting to determine the permanent enabled state");
620         if (rc)
621                 return 0;
622
623         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
624         return rc;
625 }
626 EXPORT_SYMBOL_GPL(tpm_show_enabled);
627
628 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
629                         char *buf)
630 {
631         cap_t cap;
632         ssize_t rc;
633
634         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
635                          "attempting to determine the permanent active state");
636         if (rc)
637                 return 0;
638
639         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
640         return rc;
641 }
642 EXPORT_SYMBOL_GPL(tpm_show_active);
643
644 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
645                         char *buf)
646 {
647         cap_t cap;
648         ssize_t rc;
649
650         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
651                          "attempting to determine the owner state");
652         if (rc)
653                 return 0;
654
655         rc = sprintf(buf, "%d\n", cap.owned);
656         return rc;
657 }
658 EXPORT_SYMBOL_GPL(tpm_show_owned);
659
660 ssize_t tpm_show_temp_deactivated(struct device * dev,
661                                 struct device_attribute * attr, char *buf)
662 {
663         cap_t cap;
664         ssize_t rc;
665
666         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
667                          "attempting to determine the temporary state");
668         if (rc)
669                 return 0;
670
671         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
672         return rc;
673 }
674 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
675
676 /*
677  * tpm_chip_find_get - return tpm_chip for given chip number
678  */
679 static struct tpm_chip *tpm_chip_find_get(int chip_num)
680 {
681         struct tpm_chip *pos, *chip = NULL;
682
683         rcu_read_lock();
684         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
685                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
686                         continue;
687
688                 if (try_module_get(pos->dev->driver->owner)) {
689                         chip = pos;
690                         break;
691                 }
692         }
693         rcu_read_unlock();
694         return chip;
695 }
696
697 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
698 #define READ_PCR_RESULT_SIZE 30
699 static struct tpm_input_header pcrread_header = {
700         .tag = TPM_TAG_RQU_COMMAND,
701         .length = cpu_to_be32(14),
702         .ordinal = TPM_ORDINAL_PCRREAD
703 };
704
705 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
706 {
707         int rc;
708         struct tpm_cmd_t cmd;
709
710         cmd.header.in = pcrread_header;
711         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
712         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
713                           "attempting to read a pcr value");
714
715         if (rc == 0)
716                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
717                        TPM_DIGEST_SIZE);
718         return rc;
719 }
720
721 /**
722  * tpm_pcr_read - read a pcr value
723  * @chip_num:   tpm idx # or ANY
724  * @pcr_idx:    pcr idx to retrieve
725  * @res_buf:    TPM_PCR value
726  *              size of res_buf is 20 bytes (or NULL if you don't care)
727  *
728  * The TPM driver should be built-in, but for whatever reason it
729  * isn't, protect against the chip disappearing, by incrementing
730  * the module usage count.
731  */
732 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
733 {
734         struct tpm_chip *chip;
735         int rc;
736
737         chip = tpm_chip_find_get(chip_num);
738         if (chip == NULL)
739                 return -ENODEV;
740         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
741         tpm_chip_put(chip);
742         return rc;
743 }
744 EXPORT_SYMBOL_GPL(tpm_pcr_read);
745
746 /**
747  * tpm_pcr_extend - extend pcr value with hash
748  * @chip_num:   tpm idx # or AN&
749  * @pcr_idx:    pcr idx to extend
750  * @hash:       hash value used to extend pcr value
751  *
752  * The TPM driver should be built-in, but for whatever reason it
753  * isn't, protect against the chip disappearing, by incrementing
754  * the module usage count.
755  */
756 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
757 #define EXTEND_PCR_RESULT_SIZE 34
758 static struct tpm_input_header pcrextend_header = {
759         .tag = TPM_TAG_RQU_COMMAND,
760         .length = cpu_to_be32(34),
761         .ordinal = TPM_ORD_PCR_EXTEND
762 };
763
764 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
765 {
766         struct tpm_cmd_t cmd;
767         int rc;
768         struct tpm_chip *chip;
769
770         chip = tpm_chip_find_get(chip_num);
771         if (chip == NULL)
772                 return -ENODEV;
773
774         cmd.header.in = pcrextend_header;
775         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
776         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
777         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
778                           "attempting extend a PCR value");
779
780         tpm_chip_put(chip);
781         return rc;
782 }
783 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
784
785 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
786 {
787         struct tpm_chip *chip;
788         int rc;
789
790         chip = tpm_chip_find_get(chip_num);
791         if (chip == NULL)
792                 return -ENODEV;
793
794         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
795
796         tpm_chip_put(chip);
797         return rc;
798 }
799 EXPORT_SYMBOL_GPL(tpm_send);
800
801 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
802                       char *buf)
803 {
804         cap_t cap;
805         u8 digest[TPM_DIGEST_SIZE];
806         ssize_t rc;
807         int i, j, num_pcrs;
808         char *str = buf;
809         struct tpm_chip *chip = dev_get_drvdata(dev);
810
811         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
812                         "attempting to determine the number of PCRS");
813         if (rc)
814                 return 0;
815
816         num_pcrs = be32_to_cpu(cap.num_pcrs);
817         for (i = 0; i < num_pcrs; i++) {
818                 rc = __tpm_pcr_read(chip, i, digest);
819                 if (rc)
820                         break;
821                 str += sprintf(str, "PCR-%02d: ", i);
822                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
823                         str += sprintf(str, "%02X ", digest[j]);
824                 str += sprintf(str, "\n");
825         }
826         return str - buf;
827 }
828 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
829
830 #define  READ_PUBEK_RESULT_SIZE 314
831 #define TPM_ORD_READPUBEK cpu_to_be32(124)
832 struct tpm_input_header tpm_readpubek_header = {
833         .tag = TPM_TAG_RQU_COMMAND,
834         .length = cpu_to_be32(30),
835         .ordinal = TPM_ORD_READPUBEK
836 };
837
838 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
839                        char *buf)
840 {
841         u8 *data;
842         struct tpm_cmd_t tpm_cmd;
843         ssize_t err;
844         int i, rc;
845         char *str = buf;
846
847         struct tpm_chip *chip = dev_get_drvdata(dev);
848
849         tpm_cmd.header.in = tpm_readpubek_header;
850         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
851                         "attempting to read the PUBEK");
852         if (err)
853                 goto out;
854
855         /* 
856            ignore header 10 bytes
857            algorithm 32 bits (1 == RSA )
858            encscheme 16 bits
859            sigscheme 16 bits
860            parameters (RSA 12->bytes: keybit, #primes, expbit)  
861            keylenbytes 32 bits
862            256 byte modulus
863            ignore checksum 20 bytes
864          */
865         data = tpm_cmd.params.readpubek_out_buffer;
866         str +=
867             sprintf(str,
868                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
869                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
870                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
871                     "Modulus length: %d\nModulus: \n",
872                     data[10], data[11], data[12], data[13], data[14],
873                     data[15], data[16], data[17], data[22], data[23],
874                     data[24], data[25], data[26], data[27], data[28],
875                     data[29], data[30], data[31], data[32], data[33],
876                     be32_to_cpu(*((__be32 *) (data + 34))));
877
878         for (i = 0; i < 256; i++) {
879                 str += sprintf(str, "%02X ", data[i + 38]);
880                 if ((i + 1) % 16 == 0)
881                         str += sprintf(str, "\n");
882         }
883 out:
884         rc = str - buf;
885         return rc;
886 }
887 EXPORT_SYMBOL_GPL(tpm_show_pubek);
888
889
890 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
891                       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
904         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
905                         "attempting to determine the 1.1 version");
906         if (rc)
907                 return 0;
908         str += sprintf(str,
909                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
910                        cap.tpm_version.Major, cap.tpm_version.Minor,
911                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
912         return str - buf;
913 }
914 EXPORT_SYMBOL_GPL(tpm_show_caps);
915
916 ssize_t tpm_show_caps_1_2(struct device * dev,
917                           struct device_attribute * attr, char *buf)
918 {
919         cap_t cap;
920         ssize_t rc;
921         char *str = buf;
922
923         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
924                         "attempting to determine the manufacturer");
925         if (rc)
926                 return 0;
927         str += sprintf(str, "Manufacturer: 0x%x\n",
928                        be32_to_cpu(cap.manufacturer_id));
929         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
930                          "attempting to determine the 1.2 version");
931         if (rc)
932                 return 0;
933         str += sprintf(str,
934                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
935                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
936                        cap.tpm_version_1_2.revMajor,
937                        cap.tpm_version_1_2.revMinor);
938         return str - buf;
939 }
940 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
941
942 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
943                         const char *buf, size_t count)
944 {
945         struct tpm_chip *chip = dev_get_drvdata(dev);
946         if (chip == NULL)
947                 return 0;
948
949         chip->vendor.cancel(chip);
950         return count;
951 }
952 EXPORT_SYMBOL_GPL(tpm_store_cancel);
953
954 /*
955  * Device file system interface to the TPM
956  *
957  * It's assured that the chip will be opened just once,
958  * by the check of is_open variable, which is protected
959  * by driver_lock.
960  */
961 int tpm_open(struct inode *inode, struct file *file)
962 {
963         int minor = iminor(inode);
964         struct tpm_chip *chip = NULL, *pos;
965
966         rcu_read_lock();
967         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
968                 if (pos->vendor.miscdev.minor == minor) {
969                         chip = pos;
970                         get_device(chip->dev);
971                         break;
972                 }
973         }
974         rcu_read_unlock();
975
976         if (!chip)
977                 return -ENODEV;
978
979         if (test_and_set_bit(0, &chip->is_open)) {
980                 dev_dbg(chip->dev, "Another process owns this TPM\n");
981                 put_device(chip->dev);
982                 return -EBUSY;
983         }
984
985         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
986         if (chip->data_buffer == NULL) {
987                 clear_bit(0, &chip->is_open);
988                 put_device(chip->dev);
989                 return -ENOMEM;
990         }
991
992         atomic_set(&chip->data_pending, 0);
993
994         file->private_data = chip;
995         return 0;
996 }
997 EXPORT_SYMBOL_GPL(tpm_open);
998
999 /*
1000  * Called on file close
1001  */
1002 int tpm_release(struct inode *inode, struct file *file)
1003 {
1004         struct tpm_chip *chip = file->private_data;
1005
1006         del_singleshot_timer_sync(&chip->user_read_timer);
1007         flush_work_sync(&chip->work);
1008         file->private_data = NULL;
1009         atomic_set(&chip->data_pending, 0);
1010         kfree(chip->data_buffer);
1011         clear_bit(0, &chip->is_open);
1012         put_device(chip->dev);
1013         return 0;
1014 }
1015 EXPORT_SYMBOL_GPL(tpm_release);
1016
1017 ssize_t tpm_write(struct file *file, const char __user *buf,
1018                   size_t size, loff_t *off)
1019 {
1020         struct tpm_chip *chip = file->private_data;
1021         size_t in_size = size, out_size;
1022
1023         /* cannot perform a write until the read has cleared
1024            either via tpm_read or a user_read_timer timeout */
1025         while (atomic_read(&chip->data_pending) != 0)
1026                 msleep(TPM_TIMEOUT);
1027
1028         mutex_lock(&chip->buffer_mutex);
1029
1030         if (in_size > TPM_BUFSIZE)
1031                 in_size = TPM_BUFSIZE;
1032
1033         if (copy_from_user
1034             (chip->data_buffer, (void __user *) buf, in_size)) {
1035                 mutex_unlock(&chip->buffer_mutex);
1036                 return -EFAULT;
1037         }
1038
1039         /* atomic tpm command send and result receive */
1040         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1041
1042         atomic_set(&chip->data_pending, out_size);
1043         mutex_unlock(&chip->buffer_mutex);
1044
1045         /* Set a timeout by which the reader must come claim the result */
1046         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1047
1048         return in_size;
1049 }
1050 EXPORT_SYMBOL_GPL(tpm_write);
1051
1052 ssize_t tpm_read(struct file *file, char __user *buf,
1053                  size_t size, loff_t *off)
1054 {
1055         struct tpm_chip *chip = file->private_data;
1056         ssize_t ret_size;
1057
1058         del_singleshot_timer_sync(&chip->user_read_timer);
1059         flush_work_sync(&chip->work);
1060         ret_size = atomic_read(&chip->data_pending);
1061         atomic_set(&chip->data_pending, 0);
1062         if (ret_size > 0) {     /* relay data */
1063                 if (size < ret_size)
1064                         ret_size = size;
1065
1066                 mutex_lock(&chip->buffer_mutex);
1067                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1068                         ret_size = -EFAULT;
1069                 mutex_unlock(&chip->buffer_mutex);
1070         }
1071
1072         return ret_size;
1073 }
1074 EXPORT_SYMBOL_GPL(tpm_read);
1075
1076 void tpm_remove_hardware(struct device *dev)
1077 {
1078         struct tpm_chip *chip = dev_get_drvdata(dev);
1079
1080         if (chip == NULL) {
1081                 dev_err(dev, "No device data found\n");
1082                 return;
1083         }
1084
1085         spin_lock(&driver_lock);
1086         list_del_rcu(&chip->list);
1087         spin_unlock(&driver_lock);
1088         synchronize_rcu();
1089
1090         misc_deregister(&chip->vendor.miscdev);
1091         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1092         tpm_bios_log_teardown(chip->bios_dir);
1093
1094         /* write it this way to be explicit (chip->dev == dev) */
1095         put_device(chip->dev);
1096 }
1097 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1098
1099 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1100 #define SAVESTATE_RESULT_SIZE 10
1101
1102 static struct tpm_input_header savestate_header = {
1103         .tag = TPM_TAG_RQU_COMMAND,
1104         .length = cpu_to_be32(10),
1105         .ordinal = TPM_ORD_SAVESTATE
1106 };
1107
1108 /*
1109  * We are about to suspend. Save the TPM state
1110  * so that it can be restored.
1111  */
1112 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1113 {
1114         struct tpm_chip *chip = dev_get_drvdata(dev);
1115         struct tpm_cmd_t cmd;
1116         int rc;
1117
1118         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1119
1120         if (chip == NULL)
1121                 return -ENODEV;
1122
1123         /* for buggy tpm, flush pcrs with extend to selected dummy */
1124         if (tpm_suspend_pcr) {
1125                 cmd.header.in = pcrextend_header;
1126                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1127                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1128                        TPM_DIGEST_SIZE);
1129                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1130                                   "extending dummy pcr before suspend");
1131         }
1132
1133         /* now do the actual savestate */
1134         cmd.header.in = savestate_header;
1135         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1136                           "sending savestate before suspend");
1137         return rc;
1138 }
1139 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1140
1141 /*
1142  * Resume from a power safe. The BIOS already restored
1143  * the TPM state.
1144  */
1145 int tpm_pm_resume(struct device *dev)
1146 {
1147         struct tpm_chip *chip = dev_get_drvdata(dev);
1148
1149         if (chip == NULL)
1150                 return -ENODEV;
1151
1152         return 0;
1153 }
1154 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1155
1156 /* In case vendor provided release function, call it too.*/
1157
1158 void tpm_dev_vendor_release(struct tpm_chip *chip)
1159 {
1160         if (chip->vendor.release)
1161                 chip->vendor.release(chip->dev);
1162
1163         clear_bit(chip->dev_num, dev_mask);
1164         kfree(chip->vendor.miscdev.name);
1165 }
1166 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1167
1168
1169 /*
1170  * Once all references to platform device are down to 0,
1171  * release all allocated structures.
1172  */
1173 void tpm_dev_release(struct device *dev)
1174 {
1175         struct tpm_chip *chip = dev_get_drvdata(dev);
1176
1177         tpm_dev_vendor_release(chip);
1178
1179         chip->release(dev);
1180         kfree(chip);
1181 }
1182 EXPORT_SYMBOL_GPL(tpm_dev_release);
1183
1184 /*
1185  * Called from tpm_<specific>.c probe function only for devices 
1186  * the driver has determined it should claim.  Prior to calling
1187  * this function the specific probe function has called pci_enable_device
1188  * upon errant exit from this function specific probe function should call
1189  * pci_disable_device
1190  */
1191 struct tpm_chip *tpm_register_hardware(struct device *dev,
1192                                         const struct tpm_vendor_specific *entry)
1193 {
1194 #define DEVNAME_SIZE 7
1195
1196         char *devname;
1197         struct tpm_chip *chip;
1198
1199         /* Driver specific per-device data */
1200         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1201         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1202
1203         if (chip == NULL || devname == NULL)
1204                 goto out_free;
1205
1206         mutex_init(&chip->buffer_mutex);
1207         mutex_init(&chip->tpm_mutex);
1208         INIT_LIST_HEAD(&chip->list);
1209
1210         INIT_WORK(&chip->work, timeout_work);
1211
1212         setup_timer(&chip->user_read_timer, user_reader_timeout,
1213                         (unsigned long)chip);
1214
1215         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1216
1217         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1218
1219         if (chip->dev_num >= TPM_NUM_DEVICES) {
1220                 dev_err(dev, "No available tpm device numbers\n");
1221                 goto out_free;
1222         } else if (chip->dev_num == 0)
1223                 chip->vendor.miscdev.minor = TPM_MINOR;
1224         else
1225                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1226
1227         set_bit(chip->dev_num, dev_mask);
1228
1229         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1230         chip->vendor.miscdev.name = devname;
1231
1232         chip->vendor.miscdev.parent = dev;
1233         chip->dev = get_device(dev);
1234         chip->release = dev->release;
1235         dev->release = tpm_dev_release;
1236         dev_set_drvdata(dev, chip);
1237
1238         if (misc_register(&chip->vendor.miscdev)) {
1239                 dev_err(chip->dev,
1240                         "unable to misc_register %s, minor %d\n",
1241                         chip->vendor.miscdev.name,
1242                         chip->vendor.miscdev.minor);
1243                 put_device(chip->dev);
1244                 return NULL;
1245         }
1246
1247         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1248                 misc_deregister(&chip->vendor.miscdev);
1249                 put_device(chip->dev);
1250
1251                 return NULL;
1252         }
1253
1254         chip->bios_dir = tpm_bios_log_setup(devname);
1255
1256         /* Make chip available */
1257         spin_lock(&driver_lock);
1258         list_add_rcu(&chip->list, &tpm_chip_list);
1259         spin_unlock(&driver_lock);
1260
1261         return chip;
1262
1263 out_free:
1264         kfree(chip);
1265         kfree(devname);
1266         return NULL;
1267 }
1268 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1269
1270 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1271 MODULE_DESCRIPTION("TPM Driver");
1272 MODULE_VERSION("2.0");
1273 MODULE_LICENSE("GPL");