xref: /openbmc/linux/drivers/crypto/ccp/sev-dev.c (revision babbdf5b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * AMD Secure Encrypted Virtualization (SEV) interface
4  *
5  * Copyright (C) 2016,2019 Advanced Micro Devices, Inc.
6  *
7  * Author: Brijesh Singh <brijesh.singh@amd.com>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/kthread.h>
13 #include <linux/sched.h>
14 #include <linux/interrupt.h>
15 #include <linux/spinlock.h>
16 #include <linux/spinlock_types.h>
17 #include <linux/types.h>
18 #include <linux/mutex.h>
19 #include <linux/delay.h>
20 #include <linux/hw_random.h>
21 #include <linux/ccp.h>
22 #include <linux/firmware.h>
23 #include <linux/gfp.h>
24 #include <linux/cpufeature.h>
25 
26 #include <asm/smp.h>
27 
28 #include "psp-dev.h"
29 #include "sev-dev.h"
30 
31 #define DEVICE_NAME		"sev"
32 #define SEV_FW_FILE		"amd/sev.fw"
33 #define SEV_FW_NAME_SIZE	64
34 
35 static DEFINE_MUTEX(sev_cmd_mutex);
36 static struct sev_misc_dev *misc_dev;
37 
38 static int psp_cmd_timeout = 100;
39 module_param(psp_cmd_timeout, int, 0644);
40 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
41 
42 static int psp_probe_timeout = 5;
43 module_param(psp_probe_timeout, int, 0644);
44 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
45 
46 static bool psp_dead;
47 static int psp_timeout;
48 
49 /* Trusted Memory Region (TMR):
50  *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
51  *   to allocate the memory, which will return aligned memory for the specified
52  *   allocation order.
53  */
54 #define SEV_ES_TMR_SIZE		(1024 * 1024)
55 static void *sev_es_tmr;
56 
57 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
58 {
59 	struct sev_device *sev = psp_master->sev_data;
60 
61 	if (sev->api_major > maj)
62 		return true;
63 
64 	if (sev->api_major == maj && sev->api_minor >= min)
65 		return true;
66 
67 	return false;
68 }
69 
70 static void sev_irq_handler(int irq, void *data, unsigned int status)
71 {
72 	struct sev_device *sev = data;
73 	int reg;
74 
75 	/* Check if it is command completion: */
76 	if (!(status & SEV_CMD_COMPLETE))
77 		return;
78 
79 	/* Check if it is SEV command completion: */
80 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
81 	if (reg & PSP_CMDRESP_RESP) {
82 		sev->int_rcvd = 1;
83 		wake_up(&sev->int_queue);
84 	}
85 }
86 
87 static int sev_wait_cmd_ioc(struct sev_device *sev,
88 			    unsigned int *reg, unsigned int timeout)
89 {
90 	int ret;
91 
92 	ret = wait_event_timeout(sev->int_queue,
93 			sev->int_rcvd, timeout * HZ);
94 	if (!ret)
95 		return -ETIMEDOUT;
96 
97 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
98 
99 	return 0;
100 }
101 
102 static int sev_cmd_buffer_len(int cmd)
103 {
104 	switch (cmd) {
105 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
106 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
107 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
108 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
109 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
110 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
111 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
112 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
113 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
114 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
115 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
116 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
117 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
118 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
119 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
120 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
121 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
122 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
123 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
124 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
125 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
126 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
127 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
128 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
129 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
130 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
131 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
132 	case SEV_CMD_ATTESTATION_REPORT:	return sizeof(struct sev_data_attestation_report);
133 	case SEV_CMD_SEND_CANCEL:			return sizeof(struct sev_data_send_cancel);
134 	default:				return 0;
135 	}
136 
137 	return 0;
138 }
139 
140 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
141 {
142 	struct psp_device *psp = psp_master;
143 	struct sev_device *sev;
144 	unsigned int phys_lsb, phys_msb;
145 	unsigned int reg, ret = 0;
146 	int buf_len;
147 
148 	if (!psp || !psp->sev_data)
149 		return -ENODEV;
150 
151 	if (psp_dead)
152 		return -EBUSY;
153 
154 	sev = psp->sev_data;
155 
156 	buf_len = sev_cmd_buffer_len(cmd);
157 	if (WARN_ON_ONCE(!data != !buf_len))
158 		return -EINVAL;
159 
160 	/*
161 	 * Copy the incoming data to driver's scratch buffer as __pa() will not
162 	 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
163 	 * physically contiguous.
164 	 */
165 	if (data)
166 		memcpy(sev->cmd_buf, data, buf_len);
167 
168 	/* Get the physical address of the command buffer */
169 	phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0;
170 	phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0;
171 
172 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
173 		cmd, phys_msb, phys_lsb, psp_timeout);
174 
175 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
176 			     buf_len, false);
177 
178 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
179 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
180 
181 	sev->int_rcvd = 0;
182 
183 	reg = cmd;
184 	reg <<= SEV_CMDRESP_CMD_SHIFT;
185 	reg |= SEV_CMDRESP_IOC;
186 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
187 
188 	/* wait for command completion */
189 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
190 	if (ret) {
191 		if (psp_ret)
192 			*psp_ret = 0;
193 
194 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
195 		psp_dead = true;
196 
197 		return ret;
198 	}
199 
200 	psp_timeout = psp_cmd_timeout;
201 
202 	if (psp_ret)
203 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
204 
205 	if (reg & PSP_CMDRESP_ERR_MASK) {
206 		dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
207 			cmd, reg & PSP_CMDRESP_ERR_MASK);
208 		ret = -EIO;
209 	}
210 
211 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
212 			     buf_len, false);
213 
214 	/*
215 	 * Copy potential output from the PSP back to data.  Do this even on
216 	 * failure in case the caller wants to glean something from the error.
217 	 */
218 	if (data)
219 		memcpy(data, sev->cmd_buf, buf_len);
220 
221 	return ret;
222 }
223 
224 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
225 {
226 	int rc;
227 
228 	mutex_lock(&sev_cmd_mutex);
229 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
230 	mutex_unlock(&sev_cmd_mutex);
231 
232 	return rc;
233 }
234 
235 static int __sev_platform_init_locked(int *error)
236 {
237 	struct psp_device *psp = psp_master;
238 	struct sev_data_init data;
239 	struct sev_device *sev;
240 	int rc = 0;
241 
242 	if (!psp || !psp->sev_data)
243 		return -ENODEV;
244 
245 	sev = psp->sev_data;
246 
247 	if (sev->state == SEV_STATE_INIT)
248 		return 0;
249 
250 	memset(&data, 0, sizeof(data));
251 	if (sev_es_tmr) {
252 		u64 tmr_pa;
253 
254 		/*
255 		 * Do not include the encryption mask on the physical
256 		 * address of the TMR (firmware should clear it anyway).
257 		 */
258 		tmr_pa = __pa(sev_es_tmr);
259 
260 		data.flags |= SEV_INIT_FLAGS_SEV_ES;
261 		data.tmr_address = tmr_pa;
262 		data.tmr_len = SEV_ES_TMR_SIZE;
263 	}
264 
265 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
266 	if (rc)
267 		return rc;
268 
269 	sev->state = SEV_STATE_INIT;
270 
271 	/* Prepare for first SEV guest launch after INIT */
272 	wbinvd_on_all_cpus();
273 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
274 	if (rc)
275 		return rc;
276 
277 	dev_dbg(sev->dev, "SEV firmware initialized\n");
278 
279 	return rc;
280 }
281 
282 int sev_platform_init(int *error)
283 {
284 	int rc;
285 
286 	mutex_lock(&sev_cmd_mutex);
287 	rc = __sev_platform_init_locked(error);
288 	mutex_unlock(&sev_cmd_mutex);
289 
290 	return rc;
291 }
292 EXPORT_SYMBOL_GPL(sev_platform_init);
293 
294 static int __sev_platform_shutdown_locked(int *error)
295 {
296 	struct sev_device *sev = psp_master->sev_data;
297 	int ret;
298 
299 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
300 	if (ret)
301 		return ret;
302 
303 	sev->state = SEV_STATE_UNINIT;
304 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
305 
306 	return ret;
307 }
308 
309 static int sev_platform_shutdown(int *error)
310 {
311 	int rc;
312 
313 	mutex_lock(&sev_cmd_mutex);
314 	rc = __sev_platform_shutdown_locked(NULL);
315 	mutex_unlock(&sev_cmd_mutex);
316 
317 	return rc;
318 }
319 
320 static int sev_get_platform_state(int *state, int *error)
321 {
322 	struct sev_user_data_status data;
323 	int rc;
324 
325 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
326 	if (rc)
327 		return rc;
328 
329 	*state = data.state;
330 	return rc;
331 }
332 
333 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
334 {
335 	int state, rc;
336 
337 	if (!writable)
338 		return -EPERM;
339 
340 	/*
341 	 * The SEV spec requires that FACTORY_RESET must be issued in
342 	 * UNINIT state. Before we go further lets check if any guest is
343 	 * active.
344 	 *
345 	 * If FW is in WORKING state then deny the request otherwise issue
346 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
347 	 *
348 	 */
349 	rc = sev_get_platform_state(&state, &argp->error);
350 	if (rc)
351 		return rc;
352 
353 	if (state == SEV_STATE_WORKING)
354 		return -EBUSY;
355 
356 	if (state == SEV_STATE_INIT) {
357 		rc = __sev_platform_shutdown_locked(&argp->error);
358 		if (rc)
359 			return rc;
360 	}
361 
362 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
363 }
364 
365 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
366 {
367 	struct sev_user_data_status data;
368 	int ret;
369 
370 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
371 	if (ret)
372 		return ret;
373 
374 	if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
375 		ret = -EFAULT;
376 
377 	return ret;
378 }
379 
380 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
381 {
382 	struct sev_device *sev = psp_master->sev_data;
383 	int rc;
384 
385 	if (!writable)
386 		return -EPERM;
387 
388 	if (sev->state == SEV_STATE_UNINIT) {
389 		rc = __sev_platform_init_locked(&argp->error);
390 		if (rc)
391 			return rc;
392 	}
393 
394 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
395 }
396 
397 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
398 {
399 	struct sev_device *sev = psp_master->sev_data;
400 	struct sev_user_data_pek_csr input;
401 	struct sev_data_pek_csr data;
402 	void __user *input_address;
403 	void *blob = NULL;
404 	int ret;
405 
406 	if (!writable)
407 		return -EPERM;
408 
409 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
410 		return -EFAULT;
411 
412 	memset(&data, 0, sizeof(data));
413 
414 	/* userspace wants to query CSR length */
415 	if (!input.address || !input.length)
416 		goto cmd;
417 
418 	/* allocate a physically contiguous buffer to store the CSR blob */
419 	input_address = (void __user *)input.address;
420 	if (input.length > SEV_FW_BLOB_MAX_SIZE)
421 		return -EFAULT;
422 
423 	blob = kmalloc(input.length, GFP_KERNEL);
424 	if (!blob)
425 		return -ENOMEM;
426 
427 	data.address = __psp_pa(blob);
428 	data.len = input.length;
429 
430 cmd:
431 	if (sev->state == SEV_STATE_UNINIT) {
432 		ret = __sev_platform_init_locked(&argp->error);
433 		if (ret)
434 			goto e_free_blob;
435 	}
436 
437 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
438 
439 	 /* If we query the CSR length, FW responded with expected data. */
440 	input.length = data.len;
441 
442 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
443 		ret = -EFAULT;
444 		goto e_free_blob;
445 	}
446 
447 	if (blob) {
448 		if (copy_to_user(input_address, blob, input.length))
449 			ret = -EFAULT;
450 	}
451 
452 e_free_blob:
453 	kfree(blob);
454 	return ret;
455 }
456 
457 void *psp_copy_user_blob(u64 uaddr, u32 len)
458 {
459 	if (!uaddr || !len)
460 		return ERR_PTR(-EINVAL);
461 
462 	/* verify that blob length does not exceed our limit */
463 	if (len > SEV_FW_BLOB_MAX_SIZE)
464 		return ERR_PTR(-EINVAL);
465 
466 	return memdup_user((void __user *)uaddr, len);
467 }
468 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
469 
470 static int sev_get_api_version(void)
471 {
472 	struct sev_device *sev = psp_master->sev_data;
473 	struct sev_user_data_status status;
474 	int error = 0, ret;
475 
476 	ret = sev_platform_status(&status, &error);
477 	if (ret) {
478 		dev_err(sev->dev,
479 			"SEV: failed to get status. Error: %#x\n", error);
480 		return 1;
481 	}
482 
483 	sev->api_major = status.api_major;
484 	sev->api_minor = status.api_minor;
485 	sev->build = status.build;
486 	sev->state = status.state;
487 
488 	return 0;
489 }
490 
491 static int sev_get_firmware(struct device *dev,
492 			    const struct firmware **firmware)
493 {
494 	char fw_name_specific[SEV_FW_NAME_SIZE];
495 	char fw_name_subset[SEV_FW_NAME_SIZE];
496 
497 	snprintf(fw_name_specific, sizeof(fw_name_specific),
498 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
499 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
500 
501 	snprintf(fw_name_subset, sizeof(fw_name_subset),
502 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
503 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
504 
505 	/* Check for SEV FW for a particular model.
506 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
507 	 *
508 	 * or
509 	 *
510 	 * Check for SEV FW common to a subset of models.
511 	 * Ex. amd_sev_fam17h_model0xh.sbin for
512 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
513 	 *
514 	 * or
515 	 *
516 	 * Fall-back to using generic name: sev.fw
517 	 */
518 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
519 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
520 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
521 		return 0;
522 
523 	return -ENOENT;
524 }
525 
526 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
527 static int sev_update_firmware(struct device *dev)
528 {
529 	struct sev_data_download_firmware *data;
530 	const struct firmware *firmware;
531 	int ret, error, order;
532 	struct page *p;
533 	u64 data_size;
534 
535 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
536 		dev_dbg(dev, "No SEV firmware file present\n");
537 		return -1;
538 	}
539 
540 	/*
541 	 * SEV FW expects the physical address given to it to be 32
542 	 * byte aligned. Memory allocated has structure placed at the
543 	 * beginning followed by the firmware being passed to the SEV
544 	 * FW. Allocate enough memory for data structure + alignment
545 	 * padding + SEV FW.
546 	 */
547 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
548 
549 	order = get_order(firmware->size + data_size);
550 	p = alloc_pages(GFP_KERNEL, order);
551 	if (!p) {
552 		ret = -1;
553 		goto fw_err;
554 	}
555 
556 	/*
557 	 * Copy firmware data to a kernel allocated contiguous
558 	 * memory region.
559 	 */
560 	data = page_address(p);
561 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
562 
563 	data->address = __psp_pa(page_address(p) + data_size);
564 	data->len = firmware->size;
565 
566 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
567 	if (ret)
568 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
569 	else
570 		dev_info(dev, "SEV firmware update successful\n");
571 
572 	__free_pages(p, order);
573 
574 fw_err:
575 	release_firmware(firmware);
576 
577 	return ret;
578 }
579 
580 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
581 {
582 	struct sev_device *sev = psp_master->sev_data;
583 	struct sev_user_data_pek_cert_import input;
584 	struct sev_data_pek_cert_import data;
585 	void *pek_blob, *oca_blob;
586 	int ret;
587 
588 	if (!writable)
589 		return -EPERM;
590 
591 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
592 		return -EFAULT;
593 
594 	/* copy PEK certificate blobs from userspace */
595 	pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
596 	if (IS_ERR(pek_blob))
597 		return PTR_ERR(pek_blob);
598 
599 	data.reserved = 0;
600 	data.pek_cert_address = __psp_pa(pek_blob);
601 	data.pek_cert_len = input.pek_cert_len;
602 
603 	/* copy PEK certificate blobs from userspace */
604 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
605 	if (IS_ERR(oca_blob)) {
606 		ret = PTR_ERR(oca_blob);
607 		goto e_free_pek;
608 	}
609 
610 	data.oca_cert_address = __psp_pa(oca_blob);
611 	data.oca_cert_len = input.oca_cert_len;
612 
613 	/* If platform is not in INIT state then transition it to INIT */
614 	if (sev->state != SEV_STATE_INIT) {
615 		ret = __sev_platform_init_locked(&argp->error);
616 		if (ret)
617 			goto e_free_oca;
618 	}
619 
620 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
621 
622 e_free_oca:
623 	kfree(oca_blob);
624 e_free_pek:
625 	kfree(pek_blob);
626 	return ret;
627 }
628 
629 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
630 {
631 	struct sev_user_data_get_id2 input;
632 	struct sev_data_get_id data;
633 	void __user *input_address;
634 	void *id_blob = NULL;
635 	int ret;
636 
637 	/* SEV GET_ID is available from SEV API v0.16 and up */
638 	if (!sev_version_greater_or_equal(0, 16))
639 		return -ENOTSUPP;
640 
641 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
642 		return -EFAULT;
643 
644 	input_address = (void __user *)input.address;
645 
646 	if (input.address && input.length) {
647 		id_blob = kmalloc(input.length, GFP_KERNEL);
648 		if (!id_blob)
649 			return -ENOMEM;
650 
651 		data.address = __psp_pa(id_blob);
652 		data.len = input.length;
653 	} else {
654 		data.address = 0;
655 		data.len = 0;
656 	}
657 
658 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
659 
660 	/*
661 	 * Firmware will return the length of the ID value (either the minimum
662 	 * required length or the actual length written), return it to the user.
663 	 */
664 	input.length = data.len;
665 
666 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
667 		ret = -EFAULT;
668 		goto e_free;
669 	}
670 
671 	if (id_blob) {
672 		if (copy_to_user(input_address, id_blob, data.len)) {
673 			ret = -EFAULT;
674 			goto e_free;
675 		}
676 	}
677 
678 e_free:
679 	kfree(id_blob);
680 
681 	return ret;
682 }
683 
684 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
685 {
686 	struct sev_data_get_id *data;
687 	u64 data_size, user_size;
688 	void *id_blob, *mem;
689 	int ret;
690 
691 	/* SEV GET_ID available from SEV API v0.16 and up */
692 	if (!sev_version_greater_or_equal(0, 16))
693 		return -ENOTSUPP;
694 
695 	/* SEV FW expects the buffer it fills with the ID to be
696 	 * 8-byte aligned. Memory allocated should be enough to
697 	 * hold data structure + alignment padding + memory
698 	 * where SEV FW writes the ID.
699 	 */
700 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
701 	user_size = sizeof(struct sev_user_data_get_id);
702 
703 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
704 	if (!mem)
705 		return -ENOMEM;
706 
707 	data = mem;
708 	id_blob = mem + data_size;
709 
710 	data->address = __psp_pa(id_blob);
711 	data->len = user_size;
712 
713 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
714 	if (!ret) {
715 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
716 			ret = -EFAULT;
717 	}
718 
719 	kfree(mem);
720 
721 	return ret;
722 }
723 
724 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
725 {
726 	struct sev_device *sev = psp_master->sev_data;
727 	struct sev_user_data_pdh_cert_export input;
728 	void *pdh_blob = NULL, *cert_blob = NULL;
729 	struct sev_data_pdh_cert_export data;
730 	void __user *input_cert_chain_address;
731 	void __user *input_pdh_cert_address;
732 	int ret;
733 
734 	/* If platform is not in INIT state then transition it to INIT. */
735 	if (sev->state != SEV_STATE_INIT) {
736 		if (!writable)
737 			return -EPERM;
738 
739 		ret = __sev_platform_init_locked(&argp->error);
740 		if (ret)
741 			return ret;
742 	}
743 
744 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
745 		return -EFAULT;
746 
747 	memset(&data, 0, sizeof(data));
748 
749 	/* Userspace wants to query the certificate length. */
750 	if (!input.pdh_cert_address ||
751 	    !input.pdh_cert_len ||
752 	    !input.cert_chain_address)
753 		goto cmd;
754 
755 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
756 	input_cert_chain_address = (void __user *)input.cert_chain_address;
757 
758 	/* Allocate a physically contiguous buffer to store the PDH blob. */
759 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
760 		return -EFAULT;
761 
762 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
763 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
764 		return -EFAULT;
765 
766 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
767 	if (!pdh_blob)
768 		return -ENOMEM;
769 
770 	data.pdh_cert_address = __psp_pa(pdh_blob);
771 	data.pdh_cert_len = input.pdh_cert_len;
772 
773 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
774 	if (!cert_blob) {
775 		ret = -ENOMEM;
776 		goto e_free_pdh;
777 	}
778 
779 	data.cert_chain_address = __psp_pa(cert_blob);
780 	data.cert_chain_len = input.cert_chain_len;
781 
782 cmd:
783 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
784 
785 	/* If we query the length, FW responded with expected data. */
786 	input.cert_chain_len = data.cert_chain_len;
787 	input.pdh_cert_len = data.pdh_cert_len;
788 
789 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
790 		ret = -EFAULT;
791 		goto e_free_cert;
792 	}
793 
794 	if (pdh_blob) {
795 		if (copy_to_user(input_pdh_cert_address,
796 				 pdh_blob, input.pdh_cert_len)) {
797 			ret = -EFAULT;
798 			goto e_free_cert;
799 		}
800 	}
801 
802 	if (cert_blob) {
803 		if (copy_to_user(input_cert_chain_address,
804 				 cert_blob, input.cert_chain_len))
805 			ret = -EFAULT;
806 	}
807 
808 e_free_cert:
809 	kfree(cert_blob);
810 e_free_pdh:
811 	kfree(pdh_blob);
812 	return ret;
813 }
814 
815 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
816 {
817 	void __user *argp = (void __user *)arg;
818 	struct sev_issue_cmd input;
819 	int ret = -EFAULT;
820 	bool writable = file->f_mode & FMODE_WRITE;
821 
822 	if (!psp_master || !psp_master->sev_data)
823 		return -ENODEV;
824 
825 	if (ioctl != SEV_ISSUE_CMD)
826 		return -EINVAL;
827 
828 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
829 		return -EFAULT;
830 
831 	if (input.cmd > SEV_MAX)
832 		return -EINVAL;
833 
834 	mutex_lock(&sev_cmd_mutex);
835 
836 	switch (input.cmd) {
837 
838 	case SEV_FACTORY_RESET:
839 		ret = sev_ioctl_do_reset(&input, writable);
840 		break;
841 	case SEV_PLATFORM_STATUS:
842 		ret = sev_ioctl_do_platform_status(&input);
843 		break;
844 	case SEV_PEK_GEN:
845 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
846 		break;
847 	case SEV_PDH_GEN:
848 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
849 		break;
850 	case SEV_PEK_CSR:
851 		ret = sev_ioctl_do_pek_csr(&input, writable);
852 		break;
853 	case SEV_PEK_CERT_IMPORT:
854 		ret = sev_ioctl_do_pek_import(&input, writable);
855 		break;
856 	case SEV_PDH_CERT_EXPORT:
857 		ret = sev_ioctl_do_pdh_export(&input, writable);
858 		break;
859 	case SEV_GET_ID:
860 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
861 		ret = sev_ioctl_do_get_id(&input);
862 		break;
863 	case SEV_GET_ID2:
864 		ret = sev_ioctl_do_get_id2(&input);
865 		break;
866 	default:
867 		ret = -EINVAL;
868 		goto out;
869 	}
870 
871 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
872 		ret = -EFAULT;
873 out:
874 	mutex_unlock(&sev_cmd_mutex);
875 
876 	return ret;
877 }
878 
879 static const struct file_operations sev_fops = {
880 	.owner	= THIS_MODULE,
881 	.unlocked_ioctl = sev_ioctl,
882 };
883 
884 int sev_platform_status(struct sev_user_data_status *data, int *error)
885 {
886 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
887 }
888 EXPORT_SYMBOL_GPL(sev_platform_status);
889 
890 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
891 {
892 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
893 }
894 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
895 
896 int sev_guest_activate(struct sev_data_activate *data, int *error)
897 {
898 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
899 }
900 EXPORT_SYMBOL_GPL(sev_guest_activate);
901 
902 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
903 {
904 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
905 }
906 EXPORT_SYMBOL_GPL(sev_guest_decommission);
907 
908 int sev_guest_df_flush(int *error)
909 {
910 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
911 }
912 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
913 
914 static void sev_exit(struct kref *ref)
915 {
916 	misc_deregister(&misc_dev->misc);
917 	kfree(misc_dev);
918 	misc_dev = NULL;
919 }
920 
921 static int sev_misc_init(struct sev_device *sev)
922 {
923 	struct device *dev = sev->dev;
924 	int ret;
925 
926 	/*
927 	 * SEV feature support can be detected on multiple devices but the SEV
928 	 * FW commands must be issued on the master. During probe, we do not
929 	 * know the master hence we create /dev/sev on the first device probe.
930 	 * sev_do_cmd() finds the right master device to which to issue the
931 	 * command to the firmware.
932 	 */
933 	if (!misc_dev) {
934 		struct miscdevice *misc;
935 
936 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
937 		if (!misc_dev)
938 			return -ENOMEM;
939 
940 		misc = &misc_dev->misc;
941 		misc->minor = MISC_DYNAMIC_MINOR;
942 		misc->name = DEVICE_NAME;
943 		misc->fops = &sev_fops;
944 
945 		ret = misc_register(misc);
946 		if (ret)
947 			return ret;
948 
949 		kref_init(&misc_dev->refcount);
950 	} else {
951 		kref_get(&misc_dev->refcount);
952 	}
953 
954 	init_waitqueue_head(&sev->int_queue);
955 	sev->misc = misc_dev;
956 	dev_dbg(dev, "registered SEV device\n");
957 
958 	return 0;
959 }
960 
961 int sev_dev_init(struct psp_device *psp)
962 {
963 	struct device *dev = psp->dev;
964 	struct sev_device *sev;
965 	int ret = -ENOMEM;
966 
967 	if (!boot_cpu_has(X86_FEATURE_SEV)) {
968 		dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
969 		return 0;
970 	}
971 
972 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
973 	if (!sev)
974 		goto e_err;
975 
976 	sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
977 	if (!sev->cmd_buf)
978 		goto e_sev;
979 
980 	psp->sev_data = sev;
981 
982 	sev->dev = dev;
983 	sev->psp = psp;
984 
985 	sev->io_regs = psp->io_regs;
986 
987 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
988 	if (!sev->vdata) {
989 		ret = -ENODEV;
990 		dev_err(dev, "sev: missing driver data\n");
991 		goto e_buf;
992 	}
993 
994 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
995 
996 	ret = sev_misc_init(sev);
997 	if (ret)
998 		goto e_irq;
999 
1000 	dev_notice(dev, "sev enabled\n");
1001 
1002 	return 0;
1003 
1004 e_irq:
1005 	psp_clear_sev_irq_handler(psp);
1006 e_buf:
1007 	devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1008 e_sev:
1009 	devm_kfree(dev, sev);
1010 e_err:
1011 	psp->sev_data = NULL;
1012 
1013 	dev_notice(dev, "sev initialization failed\n");
1014 
1015 	return ret;
1016 }
1017 
1018 void sev_dev_destroy(struct psp_device *psp)
1019 {
1020 	struct sev_device *sev = psp->sev_data;
1021 
1022 	if (!sev)
1023 		return;
1024 
1025 	if (sev->misc)
1026 		kref_put(&misc_dev->refcount, sev_exit);
1027 
1028 	psp_clear_sev_irq_handler(psp);
1029 }
1030 
1031 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1032 				void *data, int *error)
1033 {
1034 	if (!filep || filep->f_op != &sev_fops)
1035 		return -EBADF;
1036 
1037 	return sev_do_cmd(cmd, data, error);
1038 }
1039 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1040 
1041 void sev_pci_init(void)
1042 {
1043 	struct sev_device *sev = psp_master->sev_data;
1044 	struct page *tmr_page;
1045 	int error, rc;
1046 
1047 	if (!sev)
1048 		return;
1049 
1050 	psp_timeout = psp_probe_timeout;
1051 
1052 	if (sev_get_api_version())
1053 		goto err;
1054 
1055 	/*
1056 	 * If platform is not in UNINIT state then firmware upgrade and/or
1057 	 * platform INIT command will fail. These command require UNINIT state.
1058 	 *
1059 	 * In a normal boot we should never run into case where the firmware
1060 	 * is not in UNINIT state on boot. But in case of kexec boot, a reboot
1061 	 * may not go through a typical shutdown sequence and may leave the
1062 	 * firmware in INIT or WORKING state.
1063 	 */
1064 
1065 	if (sev->state != SEV_STATE_UNINIT) {
1066 		sev_platform_shutdown(NULL);
1067 		sev->state = SEV_STATE_UNINIT;
1068 	}
1069 
1070 	if (sev_version_greater_or_equal(0, 15) &&
1071 	    sev_update_firmware(sev->dev) == 0)
1072 		sev_get_api_version();
1073 
1074 	/* Obtain the TMR memory area for SEV-ES use */
1075 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1076 	if (tmr_page) {
1077 		sev_es_tmr = page_address(tmr_page);
1078 	} else {
1079 		sev_es_tmr = NULL;
1080 		dev_warn(sev->dev,
1081 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1082 	}
1083 
1084 	/* Initialize the platform */
1085 	rc = sev_platform_init(&error);
1086 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1087 		/*
1088 		 * INIT command returned an integrity check failure
1089 		 * status code, meaning that firmware load and
1090 		 * validation of SEV related persistent data has
1091 		 * failed and persistent state has been erased.
1092 		 * Retrying INIT command here should succeed.
1093 		 */
1094 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1095 		rc = sev_platform_init(&error);
1096 	}
1097 
1098 	if (rc) {
1099 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1100 		return;
1101 	}
1102 
1103 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1104 		 sev->api_minor, sev->build);
1105 
1106 	return;
1107 
1108 err:
1109 	psp_master->sev_data = NULL;
1110 }
1111 
1112 void sev_pci_exit(void)
1113 {
1114 	if (!psp_master->sev_data)
1115 		return;
1116 
1117 	sev_platform_shutdown(NULL);
1118 
1119 	if (sev_es_tmr) {
1120 		/* The TMR area was encrypted, flush it from the cache */
1121 		wbinvd_on_all_cpus();
1122 
1123 		free_pages((unsigned long)sev_es_tmr,
1124 			   get_order(SEV_ES_TMR_SIZE));
1125 		sev_es_tmr = NULL;
1126 	}
1127 }
1128