[PATCH] tpm: fix misc name memory problem
[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/sched.h>
27 #include <linux/poll.h>
28 #include <linux/spinlock.h>
29 #include "tpm.h"
30
31 enum tpm_const {
32         TPM_MINOR = 224,        /* officially assigned */
33         TPM_BUFSIZE = 2048,
34         TPM_NUM_DEVICES = 256,
35         TPM_NUM_MASK_ENTRIES = TPM_NUM_DEVICES / (8 * sizeof(int))
36 };
37
38 static LIST_HEAD(tpm_chip_list);
39 static DEFINE_SPINLOCK(driver_lock);
40 static int dev_mask[TPM_NUM_MASK_ENTRIES];
41
42 static void user_reader_timeout(unsigned long ptr)
43 {
44         struct tpm_chip *chip = (struct tpm_chip *) ptr;
45
46         down(&chip->buffer_mutex);
47         atomic_set(&chip->data_pending, 0);
48         memset(chip->data_buffer, 0, TPM_BUFSIZE);
49         up(&chip->buffer_mutex);
50 }
51
52 /*
53  * Internal kernel interface to transmit TPM commands
54  */
55 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
56                             size_t bufsiz)
57 {
58         ssize_t rc;
59         u32 count;
60         unsigned long stop;
61
62         count = be32_to_cpu(*((__be32 *) (buf + 2)));
63
64         if (count == 0)
65                 return -ENODATA;
66         if (count > bufsiz) {
67                 dev_err(&chip->pci_dev->dev,
68                         "invalid count value %x %zx \n", count, bufsiz);
69                 return -E2BIG;
70         }
71
72         down(&chip->tpm_mutex);
73
74         if ((rc = chip->vendor->send(chip, (u8 *) buf, count)) < 0) {
75                 dev_err(&chip->pci_dev->dev,
76                         "tpm_transmit: tpm_send: error %zd\n", rc);
77                 goto out;
78         }
79
80         stop = jiffies + 2 * 60 * HZ;
81         do {
82                 u8 status = inb(chip->vendor->base + 1);
83                 if ((status & chip->vendor->req_complete_mask) ==
84                     chip->vendor->req_complete_val) {
85                         goto out_recv;
86                 }
87
88                 if ((status == chip->vendor->req_canceled)) {
89                         dev_err(&chip->pci_dev->dev, "Operation Canceled\n");
90                         rc = -ECANCELED;
91                         goto out;
92                 }
93
94                 msleep(TPM_TIMEOUT);    /* CHECK */
95                 rmb();
96         } while (time_before(jiffies, stop));
97
98
99         chip->vendor->cancel(chip);
100         dev_err(&chip->pci_dev->dev, "Operation Timed out\n");
101         rc = -ETIME;
102         goto out;
103
104 out_recv:
105         rc = chip->vendor->recv(chip, (u8 *) buf, bufsiz);
106         if (rc < 0)
107                 dev_err(&chip->pci_dev->dev,
108                         "tpm_transmit: tpm_recv: error %zd\n", rc);
109 out:
110         up(&chip->tpm_mutex);
111         return rc;
112 }
113
114 #define TPM_DIGEST_SIZE 20
115 #define CAP_PCR_RESULT_SIZE 18
116 static const u8 cap_pcr[] = {
117         0, 193,                 /* TPM_TAG_RQU_COMMAND */
118         0, 0, 0, 22,            /* length */
119         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
120         0, 0, 0, 5,
121         0, 0, 0, 4,
122         0, 0, 1, 1
123 };
124
125 #define READ_PCR_RESULT_SIZE 30
126 static const u8 pcrread[] = {
127         0, 193,                 /* TPM_TAG_RQU_COMMAND */
128         0, 0, 0, 14,            /* length */
129         0, 0, 0, 21,            /* TPM_ORD_PcrRead */
130         0, 0, 0, 0              /* PCR index */
131 };
132
133 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
134                       char *buf)
135 {
136         u8 data[READ_PCR_RESULT_SIZE];
137         ssize_t len;
138         int i, j, num_pcrs;
139         __be32 index;
140         char *str = buf;
141
142         struct tpm_chip *chip =
143             pci_get_drvdata(to_pci_dev(dev));
144         if (chip == NULL)
145                 return -ENODEV;
146
147         memcpy(data, cap_pcr, sizeof(cap_pcr));
148         if ((len = tpm_transmit(chip, data, sizeof(data)))
149             < CAP_PCR_RESULT_SIZE) {
150                 dev_dbg(&chip->pci_dev->dev, "A TPM error (%d) occurred "
151                                 "attempting to determine the number of PCRS\n",
152                         be32_to_cpu(*((__be32 *) (data + 6))));
153                 return 0;
154         }
155
156         num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
157
158         for (i = 0; i < num_pcrs; i++) {
159                 memcpy(data, pcrread, sizeof(pcrread));
160                 index = cpu_to_be32(i);
161                 memcpy(data + 10, &index, 4);
162                 if ((len = tpm_transmit(chip, data, sizeof(data)))
163                     < READ_PCR_RESULT_SIZE){
164                         dev_dbg(&chip->pci_dev->dev, "A TPM error (%d) occurred"
165                                 " attempting to read PCR %d of %d\n",
166                                 be32_to_cpu(*((__be32 *) (data + 6))), i, num_pcrs);
167                         goto out;
168                 }
169                 str += sprintf(str, "PCR-%02d: ", i);
170                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
171                         str += sprintf(str, "%02X ", *(data + 10 + j));
172                 str += sprintf(str, "\n");
173         }
174 out:
175         return str - buf;
176 }
177 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
178
179 #define  READ_PUBEK_RESULT_SIZE 314
180 static const u8 readpubek[] = {
181         0, 193,                 /* TPM_TAG_RQU_COMMAND */
182         0, 0, 0, 30,            /* length */
183         0, 0, 0, 124,           /* TPM_ORD_ReadPubek */
184 };
185
186 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
187                        char *buf)
188 {
189         u8 *data;
190         ssize_t len;
191         int i, rc;
192         char *str = buf;
193
194         struct tpm_chip *chip =
195             pci_get_drvdata(to_pci_dev(dev));
196         if (chip == NULL)
197                 return -ENODEV;
198
199         data = kmalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
200         if (!data)
201                 return -ENOMEM;
202
203         memcpy(data, readpubek, sizeof(readpubek));
204         memset(data + sizeof(readpubek), 0, 20);        /* zero nonce */
205
206         if ((len = tpm_transmit(chip, data, READ_PUBEK_RESULT_SIZE)) <
207             READ_PUBEK_RESULT_SIZE) {
208                 dev_dbg(&chip->pci_dev->dev, "A TPM error (%d) occurred "
209                                 "attempting to read the PUBEK\n",
210                             be32_to_cpu(*((__be32 *) (data + 6))));
211                 rc = 0;
212                 goto out;
213         }
214
215         /* 
216            ignore header 10 bytes
217            algorithm 32 bits (1 == RSA )
218            encscheme 16 bits
219            sigscheme 16 bits
220            parameters (RSA 12->bytes: keybit, #primes, expbit)  
221            keylenbytes 32 bits
222            256 byte modulus
223            ignore checksum 20 bytes
224          */
225
226         str +=
227             sprintf(str,
228                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
229                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
230                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
231                     "Modulus length: %d\nModulus: \n",
232                     data[10], data[11], data[12], data[13], data[14],
233                     data[15], data[16], data[17], data[22], data[23],
234                     data[24], data[25], data[26], data[27], data[28],
235                     data[29], data[30], data[31], data[32], data[33],
236                     be32_to_cpu(*((__be32 *) (data + 34))));
237
238         for (i = 0; i < 256; i++) {
239                 str += sprintf(str, "%02X ", data[i + 38]);
240                 if ((i + 1) % 16 == 0)
241                         str += sprintf(str, "\n");
242         }
243         rc = str - buf;
244 out:
245         kfree(data);
246         return rc;
247 }
248
249 EXPORT_SYMBOL_GPL(tpm_show_pubek);
250
251 #define CAP_VER_RESULT_SIZE 18
252 static const u8 cap_version[] = {
253         0, 193,                 /* TPM_TAG_RQU_COMMAND */
254         0, 0, 0, 18,            /* length */
255         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
256         0, 0, 0, 6,
257         0, 0, 0, 0
258 };
259
260 #define CAP_MANUFACTURER_RESULT_SIZE 18
261 static const u8 cap_manufacturer[] = {
262         0, 193,                 /* TPM_TAG_RQU_COMMAND */
263         0, 0, 0, 22,            /* length */
264         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
265         0, 0, 0, 5,
266         0, 0, 0, 4,
267         0, 0, 1, 3
268 };
269
270 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
271                       char *buf)
272 {
273         u8 data[sizeof(cap_manufacturer)];
274         ssize_t len;
275         char *str = buf;
276
277         struct tpm_chip *chip =
278             pci_get_drvdata(to_pci_dev(dev));
279         if (chip == NULL)
280                 return -ENODEV;
281
282         memcpy(data, cap_manufacturer, sizeof(cap_manufacturer));
283
284         if ((len = tpm_transmit(chip, data, sizeof(data))) <
285             CAP_MANUFACTURER_RESULT_SIZE)
286                 return len;
287
288         str += sprintf(str, "Manufacturer: 0x%x\n",
289                        be32_to_cpu(*((__be32 *) (data + 14))));
290
291         memcpy(data, cap_version, sizeof(cap_version));
292
293         if ((len = tpm_transmit(chip, data, sizeof(data))) <
294             CAP_VER_RESULT_SIZE)
295                 return len;
296
297         str +=
298             sprintf(str, "TCG version: %d.%d\nFirmware version: %d.%d\n",
299                     (int) data[14], (int) data[15], (int) data[16],
300                     (int) data[17]);
301
302         return str - buf;
303 }
304 EXPORT_SYMBOL_GPL(tpm_show_caps);
305
306 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
307                         const char *buf, size_t count)
308 {
309         struct tpm_chip *chip = dev_get_drvdata(dev);
310         if (chip == NULL)
311                 return 0;
312
313         chip->vendor->cancel(chip);
314         return count;
315 }
316 EXPORT_SYMBOL_GPL(tpm_store_cancel);
317
318
319 /*
320  * Device file system interface to the TPM
321  */
322 int tpm_open(struct inode *inode, struct file *file)
323 {
324         int rc = 0, minor = iminor(inode);
325         struct tpm_chip *chip = NULL, *pos;
326
327         spin_lock(&driver_lock);
328
329         list_for_each_entry(pos, &tpm_chip_list, list) {
330                 if (pos->vendor->miscdev.minor == minor) {
331                         chip = pos;
332                         break;
333                 }
334         }
335
336         if (chip == NULL) {
337                 rc = -ENODEV;
338                 goto err_out;
339         }
340
341         if (chip->num_opens) {
342                 dev_dbg(&chip->pci_dev->dev,
343                         "Another process owns this TPM\n");
344                 rc = -EBUSY;
345                 goto err_out;
346         }
347
348         chip->num_opens++;
349         pci_dev_get(chip->pci_dev);
350
351         spin_unlock(&driver_lock);
352
353         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
354         if (chip->data_buffer == NULL) {
355                 chip->num_opens--;
356                 pci_dev_put(chip->pci_dev);
357                 return -ENOMEM;
358         }
359
360         atomic_set(&chip->data_pending, 0);
361
362         file->private_data = chip;
363         return 0;
364
365 err_out:
366         spin_unlock(&driver_lock);
367         return rc;
368 }
369
370 EXPORT_SYMBOL_GPL(tpm_open);
371
372 int tpm_release(struct inode *inode, struct file *file)
373 {
374         struct tpm_chip *chip = file->private_data;
375
376         spin_lock(&driver_lock);
377         file->private_data = NULL;
378         chip->num_opens--;
379         del_singleshot_timer_sync(&chip->user_read_timer);
380         atomic_set(&chip->data_pending, 0);
381         pci_dev_put(chip->pci_dev);
382         kfree(chip->data_buffer);
383         spin_unlock(&driver_lock);
384         return 0;
385 }
386
387 EXPORT_SYMBOL_GPL(tpm_release);
388
389 ssize_t tpm_write(struct file * file, const char __user * buf,
390                   size_t size, loff_t * off)
391 {
392         struct tpm_chip *chip = file->private_data;
393         int in_size = size, out_size;
394
395         /* cannot perform a write until the read has cleared
396            either via tpm_read or a user_read_timer timeout */
397         while (atomic_read(&chip->data_pending) != 0)
398                 msleep(TPM_TIMEOUT);
399
400         down(&chip->buffer_mutex);
401
402         if (in_size > TPM_BUFSIZE)
403                 in_size = TPM_BUFSIZE;
404
405         if (copy_from_user
406             (chip->data_buffer, (void __user *) buf, in_size)) {
407                 up(&chip->buffer_mutex);
408                 return -EFAULT;
409         }
410
411         /* atomic tpm command send and result receive */
412         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
413
414         atomic_set(&chip->data_pending, out_size);
415         up(&chip->buffer_mutex);
416
417         /* Set a timeout by which the reader must come claim the result */
418         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
419
420         return in_size;
421 }
422
423 EXPORT_SYMBOL_GPL(tpm_write);
424
425 ssize_t tpm_read(struct file * file, char __user * buf,
426                  size_t size, loff_t * off)
427 {
428         struct tpm_chip *chip = file->private_data;
429         int ret_size;
430
431         del_singleshot_timer_sync(&chip->user_read_timer);
432         ret_size = atomic_read(&chip->data_pending);
433         atomic_set(&chip->data_pending, 0);
434         if (ret_size > 0) {     /* relay data */
435                 if (size < ret_size)
436                         ret_size = size;
437
438                 down(&chip->buffer_mutex);
439                 if (copy_to_user
440                     ((void __user *) buf, chip->data_buffer, ret_size))
441                         ret_size = -EFAULT;
442                 up(&chip->buffer_mutex);
443         }
444
445         return ret_size;
446 }
447
448 EXPORT_SYMBOL_GPL(tpm_read);
449
450 void __devexit tpm_remove(struct pci_dev *pci_dev)
451 {
452         struct tpm_chip *chip = pci_get_drvdata(pci_dev);
453
454         if (chip == NULL) {
455                 dev_err(&pci_dev->dev, "No device data found\n");
456                 return;
457         }
458
459         spin_lock(&driver_lock);
460
461         list_del(&chip->list);
462
463         spin_unlock(&driver_lock);
464
465         pci_set_drvdata(pci_dev, NULL);
466         misc_deregister(&chip->vendor->miscdev);
467         kfree(&chip->vendor->miscdev.name);
468
469         sysfs_remove_group(&pci_dev->dev.kobj, chip->vendor->attr_group);
470
471         pci_disable_device(pci_dev);
472
473         dev_mask[chip->dev_num / TPM_NUM_MASK_ENTRIES ] &= !(1 << (chip->dev_num % TPM_NUM_MASK_ENTRIES));
474
475         kfree(chip);
476
477         pci_dev_put(pci_dev);
478 }
479
480 EXPORT_SYMBOL_GPL(tpm_remove);
481
482 static u8 savestate[] = {
483         0, 193,                 /* TPM_TAG_RQU_COMMAND */
484         0, 0, 0, 10,            /* blob length (in bytes) */
485         0, 0, 0, 152            /* TPM_ORD_SaveState */
486 };
487
488 /*
489  * We are about to suspend. Save the TPM state
490  * so that it can be restored.
491  */
492 int tpm_pm_suspend(struct pci_dev *pci_dev, pm_message_t pm_state)
493 {
494         struct tpm_chip *chip = pci_get_drvdata(pci_dev);
495         if (chip == NULL)
496                 return -ENODEV;
497
498         tpm_transmit(chip, savestate, sizeof(savestate));
499         return 0;
500 }
501
502 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
503
504 /*
505  * Resume from a power safe. The BIOS already restored
506  * the TPM state.
507  */
508 int tpm_pm_resume(struct pci_dev *pci_dev)
509 {
510         struct tpm_chip *chip = pci_get_drvdata(pci_dev);
511
512         if (chip == NULL)
513                 return -ENODEV;
514
515         return 0;
516 }
517
518 EXPORT_SYMBOL_GPL(tpm_pm_resume);
519
520 /*
521  * Called from tpm_<specific>.c probe function only for devices 
522  * the driver has determined it should claim.  Prior to calling
523  * this function the specific probe function has called pci_enable_device
524  * upon errant exit from this function specific probe function should call
525  * pci_disable_device
526  */
527 int tpm_register_hardware(struct pci_dev *pci_dev,
528                           struct tpm_vendor_specific *entry)
529 {
530 #define DEVNAME_SIZE 7
531
532         char *devname;
533         struct tpm_chip *chip;
534         int i, j;
535
536         /* Driver specific per-device data */
537         chip = kmalloc(sizeof(*chip), GFP_KERNEL);
538         if (chip == NULL)
539                 return -ENOMEM;
540
541         memset(chip, 0, sizeof(struct tpm_chip));
542
543         init_MUTEX(&chip->buffer_mutex);
544         init_MUTEX(&chip->tpm_mutex);
545         INIT_LIST_HEAD(&chip->list);
546
547         init_timer(&chip->user_read_timer);
548         chip->user_read_timer.function = user_reader_timeout;
549         chip->user_read_timer.data = (unsigned long) chip;
550
551         chip->vendor = entry;
552
553         chip->dev_num = -1;
554
555         for (i = 0; i < TPM_NUM_MASK_ENTRIES; i++)
556                 for (j = 0; j < 8 * sizeof(int); j++)
557                         if ((dev_mask[i] & (1 << j)) == 0) {
558                                 chip->dev_num =
559                                     i * TPM_NUM_MASK_ENTRIES + j;
560                                 dev_mask[i] |= 1 << j;
561                                 goto dev_num_search_complete;
562                         }
563
564 dev_num_search_complete:
565         if (chip->dev_num < 0) {
566                 dev_err(&pci_dev->dev,
567                         "No available tpm device numbers\n");
568                 kfree(chip);
569                 return -ENODEV;
570         } else if (chip->dev_num == 0)
571                 chip->vendor->miscdev.minor = TPM_MINOR;
572         else
573                 chip->vendor->miscdev.minor = MISC_DYNAMIC_MINOR;
574
575         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
576         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
577         chip->vendor->miscdev.name = devname;
578
579         chip->vendor->miscdev.dev = &(pci_dev->dev);
580         chip->pci_dev = pci_dev_get(pci_dev);
581
582         if (misc_register(&chip->vendor->miscdev)) {
583                 dev_err(&chip->pci_dev->dev,
584                         "unable to misc_register %s, minor %d\n",
585                         chip->vendor->miscdev.name,
586                         chip->vendor->miscdev.minor);
587                 pci_dev_put(pci_dev);
588                 kfree(chip);
589                 dev_mask[i] &= !(1 << j);
590                 return -ENODEV;
591         }
592
593         spin_lock(&driver_lock);
594
595         pci_set_drvdata(pci_dev, chip);
596
597         list_add(&chip->list, &tpm_chip_list);
598
599         spin_unlock(&driver_lock);
600
601         sysfs_create_group(&pci_dev->dev.kobj, chip->vendor->attr_group);
602
603         return 0;
604 }
605
606 EXPORT_SYMBOL_GPL(tpm_register_hardware);
607
608 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
609 MODULE_DESCRIPTION("TPM Driver");
610 MODULE_VERSION("2.0");
611 MODULE_LICENSE("GPL");