1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) 2015, 2016 IBM Corporation |
4 | * Copyright (C) 2016 Intel Corporation |
5 | * |
6 | * Author: Stefan Berger <stefanb@us.ibm.com> |
7 | * |
8 | * Maintained by: <tpmdd-devel@lists.sourceforge.net> |
9 | * |
10 | * Device driver for vTPM (vTPM proxy driver) |
11 | */ |
12 | |
13 | #include <linux/types.h> |
14 | #include <linux/spinlock.h> |
15 | #include <linux/uaccess.h> |
16 | #include <linux/wait.h> |
17 | #include <linux/miscdevice.h> |
18 | #include <linux/vtpm_proxy.h> |
19 | #include <linux/file.h> |
20 | #include <linux/anon_inodes.h> |
21 | #include <linux/poll.h> |
22 | #include <linux/compat.h> |
23 | |
24 | #include "tpm.h" |
25 | |
26 | #define VTPM_PROXY_REQ_COMPLETE_FLAG BIT(0) |
27 | |
28 | struct proxy_dev { |
29 | struct tpm_chip *chip; |
30 | |
31 | u32 flags; /* public API flags */ |
32 | |
33 | wait_queue_head_t wq; |
34 | |
35 | struct mutex buf_lock; /* protect buffer and flags */ |
36 | |
37 | long state; /* internal state */ |
38 | #define STATE_OPENED_FLAG BIT(0) |
39 | #define STATE_WAIT_RESPONSE_FLAG BIT(1) /* waiting for emulator response */ |
40 | #define STATE_REGISTERED_FLAG BIT(2) |
41 | #define STATE_DRIVER_COMMAND BIT(3) /* sending a driver specific command */ |
42 | |
43 | size_t req_len; /* length of queued TPM request */ |
44 | size_t resp_len; /* length of queued TPM response */ |
45 | u8 buffer[TPM_BUFSIZE]; /* request/response buffer */ |
46 | |
47 | struct work_struct work; /* task that retrieves TPM timeouts */ |
48 | }; |
49 | |
50 | /* all supported flags */ |
51 | #define VTPM_PROXY_FLAGS_ALL (VTPM_PROXY_FLAG_TPM2) |
52 | |
53 | static struct workqueue_struct *workqueue; |
54 | |
55 | static void vtpm_proxy_delete_device(struct proxy_dev *proxy_dev); |
56 | |
57 | /* |
58 | * Functions related to 'server side' |
59 | */ |
60 | |
61 | /** |
62 | * vtpm_proxy_fops_read - Read TPM commands on 'server side' |
63 | * |
64 | * @filp: file pointer |
65 | * @buf: read buffer |
66 | * @count: number of bytes to read |
67 | * @off: offset |
68 | * |
69 | * Return: |
70 | * Number of bytes read or negative error code |
71 | */ |
72 | static ssize_t vtpm_proxy_fops_read(struct file *filp, char __user *buf, |
73 | size_t count, loff_t *off) |
74 | { |
75 | struct proxy_dev *proxy_dev = filp->private_data; |
76 | size_t len; |
77 | int sig, rc; |
78 | |
79 | sig = wait_event_interruptible(proxy_dev->wq, |
80 | proxy_dev->req_len != 0 || |
81 | !(proxy_dev->state & STATE_OPENED_FLAG)); |
82 | if (sig) |
83 | return -EINTR; |
84 | |
85 | mutex_lock(&proxy_dev->buf_lock); |
86 | |
87 | if (!(proxy_dev->state & STATE_OPENED_FLAG)) { |
88 | mutex_unlock(lock: &proxy_dev->buf_lock); |
89 | return -EPIPE; |
90 | } |
91 | |
92 | len = proxy_dev->req_len; |
93 | |
94 | if (count < len || len > sizeof(proxy_dev->buffer)) { |
95 | mutex_unlock(lock: &proxy_dev->buf_lock); |
96 | pr_debug("Invalid size in recv: count=%zd, req_len=%zd\n" , |
97 | count, len); |
98 | return -EIO; |
99 | } |
100 | |
101 | rc = copy_to_user(to: buf, from: proxy_dev->buffer, n: len); |
102 | memset(proxy_dev->buffer, 0, len); |
103 | proxy_dev->req_len = 0; |
104 | |
105 | if (!rc) |
106 | proxy_dev->state |= STATE_WAIT_RESPONSE_FLAG; |
107 | |
108 | mutex_unlock(lock: &proxy_dev->buf_lock); |
109 | |
110 | if (rc) |
111 | return -EFAULT; |
112 | |
113 | return len; |
114 | } |
115 | |
116 | /** |
117 | * vtpm_proxy_fops_write - Write TPM responses on 'server side' |
118 | * |
119 | * @filp: file pointer |
120 | * @buf: write buffer |
121 | * @count: number of bytes to write |
122 | * @off: offset |
123 | * |
124 | * Return: |
125 | * Number of bytes read or negative error value |
126 | */ |
127 | static ssize_t vtpm_proxy_fops_write(struct file *filp, const char __user *buf, |
128 | size_t count, loff_t *off) |
129 | { |
130 | struct proxy_dev *proxy_dev = filp->private_data; |
131 | |
132 | mutex_lock(&proxy_dev->buf_lock); |
133 | |
134 | if (!(proxy_dev->state & STATE_OPENED_FLAG)) { |
135 | mutex_unlock(lock: &proxy_dev->buf_lock); |
136 | return -EPIPE; |
137 | } |
138 | |
139 | if (count > sizeof(proxy_dev->buffer) || |
140 | !(proxy_dev->state & STATE_WAIT_RESPONSE_FLAG)) { |
141 | mutex_unlock(lock: &proxy_dev->buf_lock); |
142 | return -EIO; |
143 | } |
144 | |
145 | proxy_dev->state &= ~STATE_WAIT_RESPONSE_FLAG; |
146 | |
147 | proxy_dev->req_len = 0; |
148 | |
149 | if (copy_from_user(to: proxy_dev->buffer, from: buf, n: count)) { |
150 | mutex_unlock(lock: &proxy_dev->buf_lock); |
151 | return -EFAULT; |
152 | } |
153 | |
154 | proxy_dev->resp_len = count; |
155 | |
156 | mutex_unlock(lock: &proxy_dev->buf_lock); |
157 | |
158 | wake_up_interruptible(&proxy_dev->wq); |
159 | |
160 | return count; |
161 | } |
162 | |
163 | /* |
164 | * vtpm_proxy_fops_poll - Poll status on 'server side' |
165 | * |
166 | * @filp: file pointer |
167 | * @wait: poll table |
168 | * |
169 | * Return: Poll flags |
170 | */ |
171 | static __poll_t vtpm_proxy_fops_poll(struct file *filp, poll_table *wait) |
172 | { |
173 | struct proxy_dev *proxy_dev = filp->private_data; |
174 | __poll_t ret; |
175 | |
176 | poll_wait(filp, wait_address: &proxy_dev->wq, p: wait); |
177 | |
178 | ret = EPOLLOUT; |
179 | |
180 | mutex_lock(&proxy_dev->buf_lock); |
181 | |
182 | if (proxy_dev->req_len) |
183 | ret |= EPOLLIN | EPOLLRDNORM; |
184 | |
185 | if (!(proxy_dev->state & STATE_OPENED_FLAG)) |
186 | ret |= EPOLLHUP; |
187 | |
188 | mutex_unlock(lock: &proxy_dev->buf_lock); |
189 | |
190 | return ret; |
191 | } |
192 | |
193 | /* |
194 | * vtpm_proxy_fops_open - Open vTPM device on 'server side' |
195 | * |
196 | * @filp: file pointer |
197 | * |
198 | * Called when setting up the anonymous file descriptor |
199 | */ |
200 | static void vtpm_proxy_fops_open(struct file *filp) |
201 | { |
202 | struct proxy_dev *proxy_dev = filp->private_data; |
203 | |
204 | proxy_dev->state |= STATE_OPENED_FLAG; |
205 | } |
206 | |
207 | /** |
208 | * vtpm_proxy_fops_undo_open - counter-part to vtpm_fops_open |
209 | * Call to undo vtpm_proxy_fops_open |
210 | * |
211 | *@proxy_dev: tpm proxy device |
212 | */ |
213 | static void vtpm_proxy_fops_undo_open(struct proxy_dev *proxy_dev) |
214 | { |
215 | mutex_lock(&proxy_dev->buf_lock); |
216 | |
217 | proxy_dev->state &= ~STATE_OPENED_FLAG; |
218 | |
219 | mutex_unlock(lock: &proxy_dev->buf_lock); |
220 | |
221 | /* no more TPM responses -- wake up anyone waiting for them */ |
222 | wake_up_interruptible(&proxy_dev->wq); |
223 | } |
224 | |
225 | /* |
226 | * vtpm_proxy_fops_release - Close 'server side' |
227 | * |
228 | * @inode: inode |
229 | * @filp: file pointer |
230 | * Return: |
231 | * Always returns 0. |
232 | */ |
233 | static int vtpm_proxy_fops_release(struct inode *inode, struct file *filp) |
234 | { |
235 | struct proxy_dev *proxy_dev = filp->private_data; |
236 | |
237 | filp->private_data = NULL; |
238 | |
239 | vtpm_proxy_delete_device(proxy_dev); |
240 | |
241 | return 0; |
242 | } |
243 | |
244 | static const struct file_operations vtpm_proxy_fops = { |
245 | .owner = THIS_MODULE, |
246 | .llseek = no_llseek, |
247 | .read = vtpm_proxy_fops_read, |
248 | .write = vtpm_proxy_fops_write, |
249 | .poll = vtpm_proxy_fops_poll, |
250 | .release = vtpm_proxy_fops_release, |
251 | }; |
252 | |
253 | /* |
254 | * Functions invoked by the core TPM driver to send TPM commands to |
255 | * 'server side' and receive responses from there. |
256 | */ |
257 | |
258 | /* |
259 | * Called when core TPM driver reads TPM responses from 'server side' |
260 | * |
261 | * @chip: tpm chip to use |
262 | * @buf: receive buffer |
263 | * @count: bytes to read |
264 | * Return: |
265 | * Number of TPM response bytes read, negative error value otherwise |
266 | */ |
267 | static int vtpm_proxy_tpm_op_recv(struct tpm_chip *chip, u8 *buf, size_t count) |
268 | { |
269 | struct proxy_dev *proxy_dev = dev_get_drvdata(dev: &chip->dev); |
270 | size_t len; |
271 | |
272 | /* process gone ? */ |
273 | mutex_lock(&proxy_dev->buf_lock); |
274 | |
275 | if (!(proxy_dev->state & STATE_OPENED_FLAG)) { |
276 | mutex_unlock(lock: &proxy_dev->buf_lock); |
277 | return -EPIPE; |
278 | } |
279 | |
280 | len = proxy_dev->resp_len; |
281 | if (count < len) { |
282 | dev_err(&chip->dev, |
283 | "Invalid size in recv: count=%zd, resp_len=%zd\n" , |
284 | count, len); |
285 | len = -EIO; |
286 | goto out; |
287 | } |
288 | |
289 | memcpy(buf, proxy_dev->buffer, len); |
290 | proxy_dev->resp_len = 0; |
291 | |
292 | out: |
293 | mutex_unlock(lock: &proxy_dev->buf_lock); |
294 | |
295 | return len; |
296 | } |
297 | |
298 | static int vtpm_proxy_is_driver_command(struct tpm_chip *chip, |
299 | u8 *buf, size_t count) |
300 | { |
301 | struct tpm_header *hdr = (struct tpm_header *)buf; |
302 | |
303 | if (count < sizeof(struct tpm_header)) |
304 | return 0; |
305 | |
306 | if (chip->flags & TPM_CHIP_FLAG_TPM2) { |
307 | switch (be32_to_cpu(hdr->ordinal)) { |
308 | case TPM2_CC_SET_LOCALITY: |
309 | return 1; |
310 | } |
311 | } else { |
312 | switch (be32_to_cpu(hdr->ordinal)) { |
313 | case TPM_ORD_SET_LOCALITY: |
314 | return 1; |
315 | } |
316 | } |
317 | return 0; |
318 | } |
319 | |
320 | /* |
321 | * Called when core TPM driver forwards TPM requests to 'server side'. |
322 | * |
323 | * @chip: tpm chip to use |
324 | * @buf: send buffer |
325 | * @count: bytes to send |
326 | * |
327 | * Return: |
328 | * 0 in case of success, negative error value otherwise. |
329 | */ |
330 | static int vtpm_proxy_tpm_op_send(struct tpm_chip *chip, u8 *buf, size_t count) |
331 | { |
332 | struct proxy_dev *proxy_dev = dev_get_drvdata(dev: &chip->dev); |
333 | |
334 | if (count > sizeof(proxy_dev->buffer)) { |
335 | dev_err(&chip->dev, |
336 | "Invalid size in send: count=%zd, buffer size=%zd\n" , |
337 | count, sizeof(proxy_dev->buffer)); |
338 | return -EIO; |
339 | } |
340 | |
341 | if (!(proxy_dev->state & STATE_DRIVER_COMMAND) && |
342 | vtpm_proxy_is_driver_command(chip, buf, count)) |
343 | return -EFAULT; |
344 | |
345 | mutex_lock(&proxy_dev->buf_lock); |
346 | |
347 | if (!(proxy_dev->state & STATE_OPENED_FLAG)) { |
348 | mutex_unlock(lock: &proxy_dev->buf_lock); |
349 | return -EPIPE; |
350 | } |
351 | |
352 | proxy_dev->resp_len = 0; |
353 | |
354 | proxy_dev->req_len = count; |
355 | memcpy(proxy_dev->buffer, buf, count); |
356 | |
357 | proxy_dev->state &= ~STATE_WAIT_RESPONSE_FLAG; |
358 | |
359 | mutex_unlock(lock: &proxy_dev->buf_lock); |
360 | |
361 | wake_up_interruptible(&proxy_dev->wq); |
362 | |
363 | return 0; |
364 | } |
365 | |
366 | static void vtpm_proxy_tpm_op_cancel(struct tpm_chip *chip) |
367 | { |
368 | /* not supported */ |
369 | } |
370 | |
371 | static u8 vtpm_proxy_tpm_op_status(struct tpm_chip *chip) |
372 | { |
373 | struct proxy_dev *proxy_dev = dev_get_drvdata(dev: &chip->dev); |
374 | |
375 | if (proxy_dev->resp_len) |
376 | return VTPM_PROXY_REQ_COMPLETE_FLAG; |
377 | |
378 | return 0; |
379 | } |
380 | |
381 | static bool vtpm_proxy_tpm_req_canceled(struct tpm_chip *chip, u8 status) |
382 | { |
383 | struct proxy_dev *proxy_dev = dev_get_drvdata(dev: &chip->dev); |
384 | bool ret; |
385 | |
386 | mutex_lock(&proxy_dev->buf_lock); |
387 | |
388 | ret = !(proxy_dev->state & STATE_OPENED_FLAG); |
389 | |
390 | mutex_unlock(lock: &proxy_dev->buf_lock); |
391 | |
392 | return ret; |
393 | } |
394 | |
395 | static int vtpm_proxy_request_locality(struct tpm_chip *chip, int locality) |
396 | { |
397 | struct tpm_buf buf; |
398 | int rc; |
399 | const struct tpm_header *; |
400 | struct proxy_dev *proxy_dev = dev_get_drvdata(dev: &chip->dev); |
401 | |
402 | if (chip->flags & TPM_CHIP_FLAG_TPM2) |
403 | rc = tpm_buf_init(buf: &buf, tag: TPM2_ST_SESSIONS, |
404 | TPM2_CC_SET_LOCALITY); |
405 | else |
406 | rc = tpm_buf_init(buf: &buf, TPM_TAG_RQU_COMMAND, |
407 | TPM_ORD_SET_LOCALITY); |
408 | if (rc) |
409 | return rc; |
410 | tpm_buf_append_u8(buf: &buf, value: locality); |
411 | |
412 | proxy_dev->state |= STATE_DRIVER_COMMAND; |
413 | |
414 | rc = tpm_transmit_cmd(chip, buf: &buf, min_rsp_body_length: 0, desc: "attempting to set locality" ); |
415 | |
416 | proxy_dev->state &= ~STATE_DRIVER_COMMAND; |
417 | |
418 | if (rc < 0) { |
419 | locality = rc; |
420 | goto out; |
421 | } |
422 | |
423 | header = (const struct tpm_header *)buf.data; |
424 | rc = be32_to_cpu(header->return_code); |
425 | if (rc) |
426 | locality = -1; |
427 | |
428 | out: |
429 | tpm_buf_destroy(buf: &buf); |
430 | |
431 | return locality; |
432 | } |
433 | |
434 | static const struct tpm_class_ops vtpm_proxy_tpm_ops = { |
435 | .flags = TPM_OPS_AUTO_STARTUP, |
436 | .recv = vtpm_proxy_tpm_op_recv, |
437 | .send = vtpm_proxy_tpm_op_send, |
438 | .cancel = vtpm_proxy_tpm_op_cancel, |
439 | .status = vtpm_proxy_tpm_op_status, |
440 | .req_complete_mask = VTPM_PROXY_REQ_COMPLETE_FLAG, |
441 | .req_complete_val = VTPM_PROXY_REQ_COMPLETE_FLAG, |
442 | .req_canceled = vtpm_proxy_tpm_req_canceled, |
443 | .request_locality = vtpm_proxy_request_locality, |
444 | }; |
445 | |
446 | /* |
447 | * Code related to the startup of the TPM 2 and startup of TPM 1.2 + |
448 | * retrieval of timeouts and durations. |
449 | */ |
450 | |
451 | static void vtpm_proxy_work(struct work_struct *work) |
452 | { |
453 | struct proxy_dev *proxy_dev = container_of(work, struct proxy_dev, |
454 | work); |
455 | int rc; |
456 | |
457 | rc = tpm_chip_register(chip: proxy_dev->chip); |
458 | if (rc) |
459 | vtpm_proxy_fops_undo_open(proxy_dev); |
460 | else |
461 | proxy_dev->state |= STATE_REGISTERED_FLAG; |
462 | } |
463 | |
464 | /* |
465 | * vtpm_proxy_work_stop: make sure the work has finished |
466 | * |
467 | * This function is useful when user space closed the fd |
468 | * while the driver still determines timeouts. |
469 | */ |
470 | static void vtpm_proxy_work_stop(struct proxy_dev *proxy_dev) |
471 | { |
472 | vtpm_proxy_fops_undo_open(proxy_dev); |
473 | flush_work(work: &proxy_dev->work); |
474 | } |
475 | |
476 | /* |
477 | * vtpm_proxy_work_start: Schedule the work for TPM 1.2 & 2 initialization |
478 | */ |
479 | static inline void vtpm_proxy_work_start(struct proxy_dev *proxy_dev) |
480 | { |
481 | queue_work(wq: workqueue, work: &proxy_dev->work); |
482 | } |
483 | |
484 | /* |
485 | * Code related to creation and deletion of device pairs |
486 | */ |
487 | static struct proxy_dev *vtpm_proxy_create_proxy_dev(void) |
488 | { |
489 | struct proxy_dev *proxy_dev; |
490 | struct tpm_chip *chip; |
491 | int err; |
492 | |
493 | proxy_dev = kzalloc(size: sizeof(*proxy_dev), GFP_KERNEL); |
494 | if (proxy_dev == NULL) |
495 | return ERR_PTR(error: -ENOMEM); |
496 | |
497 | init_waitqueue_head(&proxy_dev->wq); |
498 | mutex_init(&proxy_dev->buf_lock); |
499 | INIT_WORK(&proxy_dev->work, vtpm_proxy_work); |
500 | |
501 | chip = tpm_chip_alloc(NULL, ops: &vtpm_proxy_tpm_ops); |
502 | if (IS_ERR(ptr: chip)) { |
503 | err = PTR_ERR(ptr: chip); |
504 | goto err_proxy_dev_free; |
505 | } |
506 | dev_set_drvdata(dev: &chip->dev, data: proxy_dev); |
507 | |
508 | proxy_dev->chip = chip; |
509 | |
510 | return proxy_dev; |
511 | |
512 | err_proxy_dev_free: |
513 | kfree(objp: proxy_dev); |
514 | |
515 | return ERR_PTR(error: err); |
516 | } |
517 | |
518 | /* |
519 | * Undo what has been done in vtpm_create_proxy_dev |
520 | */ |
521 | static inline void vtpm_proxy_delete_proxy_dev(struct proxy_dev *proxy_dev) |
522 | { |
523 | put_device(dev: &proxy_dev->chip->dev); /* frees chip */ |
524 | kfree(objp: proxy_dev); |
525 | } |
526 | |
527 | /* |
528 | * Create a /dev/tpm%d and 'server side' file descriptor pair |
529 | * |
530 | * Return: |
531 | * Returns file pointer on success, an error value otherwise |
532 | */ |
533 | static struct file *vtpm_proxy_create_device( |
534 | struct vtpm_proxy_new_dev *vtpm_new_dev) |
535 | { |
536 | struct proxy_dev *proxy_dev; |
537 | int rc, fd; |
538 | struct file *file; |
539 | |
540 | if (vtpm_new_dev->flags & ~VTPM_PROXY_FLAGS_ALL) |
541 | return ERR_PTR(error: -EOPNOTSUPP); |
542 | |
543 | proxy_dev = vtpm_proxy_create_proxy_dev(); |
544 | if (IS_ERR(ptr: proxy_dev)) |
545 | return ERR_CAST(ptr: proxy_dev); |
546 | |
547 | proxy_dev->flags = vtpm_new_dev->flags; |
548 | |
549 | /* setup an anonymous file for the server-side */ |
550 | fd = get_unused_fd_flags(O_RDWR); |
551 | if (fd < 0) { |
552 | rc = fd; |
553 | goto err_delete_proxy_dev; |
554 | } |
555 | |
556 | file = anon_inode_getfile(name: "[vtpms]" , fops: &vtpm_proxy_fops, priv: proxy_dev, |
557 | O_RDWR); |
558 | if (IS_ERR(ptr: file)) { |
559 | rc = PTR_ERR(ptr: file); |
560 | goto err_put_unused_fd; |
561 | } |
562 | |
563 | /* from now on we can unwind with put_unused_fd() + fput() */ |
564 | /* simulate an open() on the server side */ |
565 | vtpm_proxy_fops_open(filp: file); |
566 | |
567 | if (proxy_dev->flags & VTPM_PROXY_FLAG_TPM2) |
568 | proxy_dev->chip->flags |= TPM_CHIP_FLAG_TPM2; |
569 | |
570 | vtpm_proxy_work_start(proxy_dev); |
571 | |
572 | vtpm_new_dev->fd = fd; |
573 | vtpm_new_dev->major = MAJOR(proxy_dev->chip->dev.devt); |
574 | vtpm_new_dev->minor = MINOR(proxy_dev->chip->dev.devt); |
575 | vtpm_new_dev->tpm_num = proxy_dev->chip->dev_num; |
576 | |
577 | return file; |
578 | |
579 | err_put_unused_fd: |
580 | put_unused_fd(fd); |
581 | |
582 | err_delete_proxy_dev: |
583 | vtpm_proxy_delete_proxy_dev(proxy_dev); |
584 | |
585 | return ERR_PTR(error: rc); |
586 | } |
587 | |
588 | /* |
589 | * Counter part to vtpm_create_device. |
590 | */ |
591 | static void vtpm_proxy_delete_device(struct proxy_dev *proxy_dev) |
592 | { |
593 | vtpm_proxy_work_stop(proxy_dev); |
594 | |
595 | /* |
596 | * A client may hold the 'ops' lock, so let it know that the server |
597 | * side shuts down before we try to grab the 'ops' lock when |
598 | * unregistering the chip. |
599 | */ |
600 | vtpm_proxy_fops_undo_open(proxy_dev); |
601 | |
602 | if (proxy_dev->state & STATE_REGISTERED_FLAG) |
603 | tpm_chip_unregister(chip: proxy_dev->chip); |
604 | |
605 | vtpm_proxy_delete_proxy_dev(proxy_dev); |
606 | } |
607 | |
608 | /* |
609 | * Code related to the control device /dev/vtpmx |
610 | */ |
611 | |
612 | /** |
613 | * vtpmx_ioc_new_dev - handler for the %VTPM_PROXY_IOC_NEW_DEV ioctl |
614 | * @file: /dev/vtpmx |
615 | * @ioctl: the ioctl number |
616 | * @arg: pointer to the struct vtpmx_proxy_new_dev |
617 | * |
618 | * Creates an anonymous file that is used by the process acting as a TPM to |
619 | * communicate with the client processes. The function will also add a new TPM |
620 | * device through which data is proxied to this TPM acting process. The caller |
621 | * will be provided with a file descriptor to communicate with the clients and |
622 | * major and minor numbers for the TPM device. |
623 | */ |
624 | static long vtpmx_ioc_new_dev(struct file *file, unsigned int ioctl, |
625 | unsigned long arg) |
626 | { |
627 | void __user *argp = (void __user *)arg; |
628 | struct vtpm_proxy_new_dev __user *vtpm_new_dev_p; |
629 | struct vtpm_proxy_new_dev vtpm_new_dev; |
630 | struct file *vtpm_file; |
631 | |
632 | if (!capable(CAP_SYS_ADMIN)) |
633 | return -EPERM; |
634 | |
635 | vtpm_new_dev_p = argp; |
636 | |
637 | if (copy_from_user(to: &vtpm_new_dev, from: vtpm_new_dev_p, |
638 | n: sizeof(vtpm_new_dev))) |
639 | return -EFAULT; |
640 | |
641 | vtpm_file = vtpm_proxy_create_device(vtpm_new_dev: &vtpm_new_dev); |
642 | if (IS_ERR(ptr: vtpm_file)) |
643 | return PTR_ERR(ptr: vtpm_file); |
644 | |
645 | if (copy_to_user(to: vtpm_new_dev_p, from: &vtpm_new_dev, |
646 | n: sizeof(vtpm_new_dev))) { |
647 | put_unused_fd(fd: vtpm_new_dev.fd); |
648 | fput(vtpm_file); |
649 | return -EFAULT; |
650 | } |
651 | |
652 | fd_install(fd: vtpm_new_dev.fd, file: vtpm_file); |
653 | return 0; |
654 | } |
655 | |
656 | /* |
657 | * vtpmx_fops_ioctl: ioctl on /dev/vtpmx |
658 | * |
659 | * Return: |
660 | * Returns 0 on success, a negative error code otherwise. |
661 | */ |
662 | static long vtpmx_fops_ioctl(struct file *f, unsigned int ioctl, |
663 | unsigned long arg) |
664 | { |
665 | switch (ioctl) { |
666 | case VTPM_PROXY_IOC_NEW_DEV: |
667 | return vtpmx_ioc_new_dev(file: f, ioctl, arg); |
668 | default: |
669 | return -ENOIOCTLCMD; |
670 | } |
671 | } |
672 | |
673 | static const struct file_operations vtpmx_fops = { |
674 | .owner = THIS_MODULE, |
675 | .unlocked_ioctl = vtpmx_fops_ioctl, |
676 | .compat_ioctl = compat_ptr_ioctl, |
677 | .llseek = noop_llseek, |
678 | }; |
679 | |
680 | static struct miscdevice vtpmx_miscdev = { |
681 | .minor = MISC_DYNAMIC_MINOR, |
682 | .name = "vtpmx" , |
683 | .fops = &vtpmx_fops, |
684 | }; |
685 | |
686 | static int __init vtpm_module_init(void) |
687 | { |
688 | int rc; |
689 | |
690 | workqueue = create_workqueue("tpm-vtpm" ); |
691 | if (!workqueue) { |
692 | pr_err("couldn't create workqueue\n" ); |
693 | return -ENOMEM; |
694 | } |
695 | |
696 | rc = misc_register(misc: &vtpmx_miscdev); |
697 | if (rc) { |
698 | pr_err("couldn't create vtpmx device\n" ); |
699 | destroy_workqueue(wq: workqueue); |
700 | } |
701 | |
702 | return rc; |
703 | } |
704 | |
705 | static void __exit vtpm_module_exit(void) |
706 | { |
707 | destroy_workqueue(wq: workqueue); |
708 | misc_deregister(misc: &vtpmx_miscdev); |
709 | } |
710 | |
711 | module_init(vtpm_module_init); |
712 | module_exit(vtpm_module_exit); |
713 | |
714 | MODULE_AUTHOR("Stefan Berger (stefanb@us.ibm.com)" ); |
715 | MODULE_DESCRIPTION("vTPM Driver" ); |
716 | MODULE_VERSION("0.1" ); |
717 | MODULE_LICENSE("GPL" ); |
718 | |