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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 
25 #include <asm/smp.h>
26 
27 #include "psp-dev.h"
28 #include "sev-dev.h"
29 
30 #define DEVICE_NAME		"sev"
31 #define SEV_FW_FILE		"amd/sev.fw"
32 #define SEV_FW_NAME_SIZE	64
33 
34 static DEFINE_MUTEX(sev_cmd_mutex);
35 static struct sev_misc_dev *misc_dev;
36 
37 static int psp_cmd_timeout = 100;
38 module_param(psp_cmd_timeout, int, 0644);
39 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
40 
41 static int psp_probe_timeout = 5;
42 module_param(psp_probe_timeout, int, 0644);
43 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
44 
45 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
46 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
47 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
48 
49 static bool psp_dead;
50 static int psp_timeout;
51 
52 /* Trusted Memory Region (TMR):
53  *   The TMR is a 1MB area that must be 1MB aligned.  Use the page allocator
54  *   to allocate the memory, which will return aligned memory for the specified
55  *   allocation order.
56  */
57 #define SEV_ES_TMR_SIZE		(1024 * 1024)
58 static void *sev_es_tmr;
59 
sev_version_greater_or_equal(u8 maj,u8 min)60 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
61 {
62 	struct sev_device *sev = psp_master->sev_data;
63 
64 	if (sev->api_major > maj)
65 		return true;
66 
67 	if (sev->api_major == maj && sev->api_minor >= min)
68 		return true;
69 
70 	return false;
71 }
72 
sev_irq_handler(int irq,void * data,unsigned int status)73 static void sev_irq_handler(int irq, void *data, unsigned int status)
74 {
75 	struct sev_device *sev = data;
76 	int reg;
77 
78 	/* Check if it is command completion: */
79 	if (!(status & SEV_CMD_COMPLETE))
80 		return;
81 
82 	/* Check if it is SEV command completion: */
83 	reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
84 	if (reg & PSP_CMDRESP_RESP) {
85 		sev->int_rcvd = 1;
86 		wake_up(&sev->int_queue);
87 	}
88 }
89 
sev_wait_cmd_ioc(struct sev_device * sev,unsigned int * reg,unsigned int timeout)90 static int sev_wait_cmd_ioc(struct sev_device *sev,
91 			    unsigned int *reg, unsigned int timeout)
92 {
93 	int ret;
94 
95 	ret = wait_event_timeout(sev->int_queue,
96 			sev->int_rcvd, timeout * HZ);
97 	if (!ret)
98 		return -ETIMEDOUT;
99 
100 	*reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
101 
102 	return 0;
103 }
104 
sev_cmd_buffer_len(int cmd)105 static int sev_cmd_buffer_len(int cmd)
106 {
107 	switch (cmd) {
108 	case SEV_CMD_INIT:			return sizeof(struct sev_data_init);
109 	case SEV_CMD_PLATFORM_STATUS:		return sizeof(struct sev_user_data_status);
110 	case SEV_CMD_PEK_CSR:			return sizeof(struct sev_data_pek_csr);
111 	case SEV_CMD_PEK_CERT_IMPORT:		return sizeof(struct sev_data_pek_cert_import);
112 	case SEV_CMD_PDH_CERT_EXPORT:		return sizeof(struct sev_data_pdh_cert_export);
113 	case SEV_CMD_LAUNCH_START:		return sizeof(struct sev_data_launch_start);
114 	case SEV_CMD_LAUNCH_UPDATE_DATA:	return sizeof(struct sev_data_launch_update_data);
115 	case SEV_CMD_LAUNCH_UPDATE_VMSA:	return sizeof(struct sev_data_launch_update_vmsa);
116 	case SEV_CMD_LAUNCH_FINISH:		return sizeof(struct sev_data_launch_finish);
117 	case SEV_CMD_LAUNCH_MEASURE:		return sizeof(struct sev_data_launch_measure);
118 	case SEV_CMD_ACTIVATE:			return sizeof(struct sev_data_activate);
119 	case SEV_CMD_DEACTIVATE:		return sizeof(struct sev_data_deactivate);
120 	case SEV_CMD_DECOMMISSION:		return sizeof(struct sev_data_decommission);
121 	case SEV_CMD_GUEST_STATUS:		return sizeof(struct sev_data_guest_status);
122 	case SEV_CMD_DBG_DECRYPT:		return sizeof(struct sev_data_dbg);
123 	case SEV_CMD_DBG_ENCRYPT:		return sizeof(struct sev_data_dbg);
124 	case SEV_CMD_SEND_START:		return sizeof(struct sev_data_send_start);
125 	case SEV_CMD_SEND_UPDATE_DATA:		return sizeof(struct sev_data_send_update_data);
126 	case SEV_CMD_SEND_UPDATE_VMSA:		return sizeof(struct sev_data_send_update_vmsa);
127 	case SEV_CMD_SEND_FINISH:		return sizeof(struct sev_data_send_finish);
128 	case SEV_CMD_RECEIVE_START:		return sizeof(struct sev_data_receive_start);
129 	case SEV_CMD_RECEIVE_FINISH:		return sizeof(struct sev_data_receive_finish);
130 	case SEV_CMD_RECEIVE_UPDATE_DATA:	return sizeof(struct sev_data_receive_update_data);
131 	case SEV_CMD_RECEIVE_UPDATE_VMSA:	return sizeof(struct sev_data_receive_update_vmsa);
132 	case SEV_CMD_LAUNCH_UPDATE_SECRET:	return sizeof(struct sev_data_launch_secret);
133 	case SEV_CMD_DOWNLOAD_FIRMWARE:		return sizeof(struct sev_data_download_firmware);
134 	case SEV_CMD_GET_ID:			return sizeof(struct sev_data_get_id);
135 	default:				return 0;
136 	}
137 
138 	return 0;
139 }
140 
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)141 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
142 {
143 	struct psp_device *psp = psp_master;
144 	struct sev_device *sev;
145 	unsigned int phys_lsb, phys_msb;
146 	unsigned int reg, ret = 0;
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 	if (data && WARN_ON_ONCE(!virt_addr_valid(data)))
157 		return -EINVAL;
158 
159 	/* Get the physical address of the command buffer */
160 	phys_lsb = data ? lower_32_bits(__psp_pa(data)) : 0;
161 	phys_msb = data ? upper_32_bits(__psp_pa(data)) : 0;
162 
163 	dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
164 		cmd, phys_msb, phys_lsb, psp_timeout);
165 
166 	print_hex_dump_debug("(in):  ", DUMP_PREFIX_OFFSET, 16, 2, data,
167 			     sev_cmd_buffer_len(cmd), false);
168 
169 	iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
170 	iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
171 
172 	sev->int_rcvd = 0;
173 
174 	reg = cmd;
175 	reg <<= SEV_CMDRESP_CMD_SHIFT;
176 	reg |= SEV_CMDRESP_IOC;
177 	iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
178 
179 	/* wait for command completion */
180 	ret = sev_wait_cmd_ioc(sev, &reg, psp_timeout);
181 	if (ret) {
182 		if (psp_ret)
183 			*psp_ret = 0;
184 
185 		dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
186 		psp_dead = true;
187 
188 		return ret;
189 	}
190 
191 	psp_timeout = psp_cmd_timeout;
192 
193 	if (psp_ret)
194 		*psp_ret = reg & PSP_CMDRESP_ERR_MASK;
195 
196 	if (reg & PSP_CMDRESP_ERR_MASK) {
197 		dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
198 			cmd, reg & PSP_CMDRESP_ERR_MASK);
199 		ret = -EIO;
200 	}
201 
202 	print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
203 			     sev_cmd_buffer_len(cmd), false);
204 
205 	return ret;
206 }
207 
sev_do_cmd(int cmd,void * data,int * psp_ret)208 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
209 {
210 	int rc;
211 
212 	mutex_lock(&sev_cmd_mutex);
213 	rc = __sev_do_cmd_locked(cmd, data, psp_ret);
214 	mutex_unlock(&sev_cmd_mutex);
215 
216 	return rc;
217 }
218 
__sev_platform_init_locked(int * error)219 static int __sev_platform_init_locked(int *error)
220 {
221 	struct psp_device *psp = psp_master;
222 	struct sev_device *sev;
223 	int rc = 0;
224 
225 	if (!psp || !psp->sev_data)
226 		return -ENODEV;
227 
228 	sev = psp->sev_data;
229 
230 	if (sev->state == SEV_STATE_INIT)
231 		return 0;
232 
233 	if (sev_es_tmr) {
234 		u64 tmr_pa;
235 
236 		/*
237 		 * Do not include the encryption mask on the physical
238 		 * address of the TMR (firmware should clear it anyway).
239 		 */
240 		tmr_pa = __pa(sev_es_tmr);
241 
242 		sev->init_cmd_buf.flags |= SEV_INIT_FLAGS_SEV_ES;
243 		sev->init_cmd_buf.tmr_address = tmr_pa;
244 		sev->init_cmd_buf.tmr_len = SEV_ES_TMR_SIZE;
245 	}
246 
247 	rc = __sev_do_cmd_locked(SEV_CMD_INIT, &sev->init_cmd_buf, error);
248 	if (rc)
249 		return rc;
250 
251 	sev->state = SEV_STATE_INIT;
252 
253 	/* Prepare for first SEV guest launch after INIT */
254 	wbinvd_on_all_cpus();
255 	rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
256 	if (rc)
257 		return rc;
258 
259 	dev_dbg(sev->dev, "SEV firmware initialized\n");
260 
261 	return rc;
262 }
263 
sev_platform_init(int * error)264 int sev_platform_init(int *error)
265 {
266 	int rc;
267 
268 	mutex_lock(&sev_cmd_mutex);
269 	rc = __sev_platform_init_locked(error);
270 	mutex_unlock(&sev_cmd_mutex);
271 
272 	return rc;
273 }
274 EXPORT_SYMBOL_GPL(sev_platform_init);
275 
__sev_platform_shutdown_locked(int * error)276 static int __sev_platform_shutdown_locked(int *error)
277 {
278 	struct sev_device *sev = psp_master->sev_data;
279 	int ret;
280 
281 	if (!sev || sev->state == SEV_STATE_UNINIT)
282 		return 0;
283 
284 	ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
285 	if (ret)
286 		return ret;
287 
288 	sev->state = SEV_STATE_UNINIT;
289 	dev_dbg(sev->dev, "SEV firmware shutdown\n");
290 
291 	return ret;
292 }
293 
sev_platform_shutdown(int * error)294 static int sev_platform_shutdown(int *error)
295 {
296 	int rc;
297 
298 	mutex_lock(&sev_cmd_mutex);
299 	rc = __sev_platform_shutdown_locked(NULL);
300 	mutex_unlock(&sev_cmd_mutex);
301 
302 	return rc;
303 }
304 
sev_get_platform_state(int * state,int * error)305 static int sev_get_platform_state(int *state, int *error)
306 {
307 	struct sev_device *sev = psp_master->sev_data;
308 	int rc;
309 
310 	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
311 				 &sev->status_cmd_buf, error);
312 	if (rc)
313 		return rc;
314 
315 	*state = sev->status_cmd_buf.state;
316 	return rc;
317 }
318 
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)319 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
320 {
321 	int state, rc;
322 
323 	if (!writable)
324 		return -EPERM;
325 
326 	/*
327 	 * The SEV spec requires that FACTORY_RESET must be issued in
328 	 * UNINIT state. Before we go further lets check if any guest is
329 	 * active.
330 	 *
331 	 * If FW is in WORKING state then deny the request otherwise issue
332 	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
333 	 *
334 	 */
335 	rc = sev_get_platform_state(&state, &argp->error);
336 	if (rc)
337 		return rc;
338 
339 	if (state == SEV_STATE_WORKING)
340 		return -EBUSY;
341 
342 	if (state == SEV_STATE_INIT) {
343 		rc = __sev_platform_shutdown_locked(&argp->error);
344 		if (rc)
345 			return rc;
346 	}
347 
348 	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
349 }
350 
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)351 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
352 {
353 	struct sev_device *sev = psp_master->sev_data;
354 	struct sev_user_data_status *data = &sev->status_cmd_buf;
355 	int ret;
356 
357 	ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, data, &argp->error);
358 	if (ret)
359 		return ret;
360 
361 	if (copy_to_user((void __user *)argp->data, data, sizeof(*data)))
362 		ret = -EFAULT;
363 
364 	return ret;
365 }
366 
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)367 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
368 {
369 	struct sev_device *sev = psp_master->sev_data;
370 	int rc;
371 
372 	if (!writable)
373 		return -EPERM;
374 
375 	if (sev->state == SEV_STATE_UNINIT) {
376 		rc = __sev_platform_init_locked(&argp->error);
377 		if (rc)
378 			return rc;
379 	}
380 
381 	return __sev_do_cmd_locked(cmd, NULL, &argp->error);
382 }
383 
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)384 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
385 {
386 	struct sev_device *sev = psp_master->sev_data;
387 	struct sev_user_data_pek_csr input;
388 	struct sev_data_pek_csr *data;
389 	void __user *input_address;
390 	void *blob = NULL;
391 	int ret;
392 
393 	if (!writable)
394 		return -EPERM;
395 
396 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
397 		return -EFAULT;
398 
399 	data = kzalloc(sizeof(*data), GFP_KERNEL);
400 	if (!data)
401 		return -ENOMEM;
402 
403 	/* userspace wants to query CSR length */
404 	if (!input.address || !input.length)
405 		goto cmd;
406 
407 	/* allocate a physically contiguous buffer to store the CSR blob */
408 	input_address = (void __user *)input.address;
409 	if (input.length > SEV_FW_BLOB_MAX_SIZE) {
410 		ret = -EFAULT;
411 		goto e_free;
412 	}
413 
414 	blob = kmalloc(input.length, GFP_KERNEL);
415 	if (!blob) {
416 		ret = -ENOMEM;
417 		goto e_free;
418 	}
419 
420 	data->address = __psp_pa(blob);
421 	data->len = input.length;
422 
423 cmd:
424 	if (sev->state == SEV_STATE_UNINIT) {
425 		ret = __sev_platform_init_locked(&argp->error);
426 		if (ret)
427 			goto e_free_blob;
428 	}
429 
430 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, data, &argp->error);
431 
432 	 /* If we query the CSR length, FW responded with expected data. */
433 	input.length = data->len;
434 
435 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
436 		ret = -EFAULT;
437 		goto e_free_blob;
438 	}
439 
440 	if (blob) {
441 		if (copy_to_user(input_address, blob, input.length))
442 			ret = -EFAULT;
443 	}
444 
445 e_free_blob:
446 	kfree(blob);
447 e_free:
448 	kfree(data);
449 	return ret;
450 }
451 
psp_copy_user_blob(u64 uaddr,u32 len)452 void *psp_copy_user_blob(u64 uaddr, u32 len)
453 {
454 	if (!uaddr || !len)
455 		return ERR_PTR(-EINVAL);
456 
457 	/* verify that blob length does not exceed our limit */
458 	if (len > SEV_FW_BLOB_MAX_SIZE)
459 		return ERR_PTR(-EINVAL);
460 
461 	return memdup_user((void __user *)uaddr, len);
462 }
463 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
464 
sev_get_api_version(void)465 static int sev_get_api_version(void)
466 {
467 	struct sev_device *sev = psp_master->sev_data;
468 	struct sev_user_data_status *status;
469 	int error = 0, ret;
470 
471 	status = &sev->status_cmd_buf;
472 	ret = sev_platform_status(status, &error);
473 	if (ret) {
474 		dev_err(sev->dev,
475 			"SEV: failed to get status. Error: %#x\n", error);
476 		return 1;
477 	}
478 
479 	sev->api_major = status->api_major;
480 	sev->api_minor = status->api_minor;
481 	sev->build = status->build;
482 	sev->state = status->state;
483 
484 	return 0;
485 }
486 
sev_get_firmware(struct device * dev,const struct firmware ** firmware)487 static int sev_get_firmware(struct device *dev,
488 			    const struct firmware **firmware)
489 {
490 	char fw_name_specific[SEV_FW_NAME_SIZE];
491 	char fw_name_subset[SEV_FW_NAME_SIZE];
492 
493 	snprintf(fw_name_specific, sizeof(fw_name_specific),
494 		 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
495 		 boot_cpu_data.x86, boot_cpu_data.x86_model);
496 
497 	snprintf(fw_name_subset, sizeof(fw_name_subset),
498 		 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
499 		 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
500 
501 	/* Check for SEV FW for a particular model.
502 	 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
503 	 *
504 	 * or
505 	 *
506 	 * Check for SEV FW common to a subset of models.
507 	 * Ex. amd_sev_fam17h_model0xh.sbin for
508 	 *     Family 17h Model 00h -- Family 17h Model 0Fh
509 	 *
510 	 * or
511 	 *
512 	 * Fall-back to using generic name: sev.fw
513 	 */
514 	if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
515 	    (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
516 	    (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
517 		return 0;
518 
519 	return -ENOENT;
520 }
521 
522 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)523 static int sev_update_firmware(struct device *dev)
524 {
525 	struct sev_data_download_firmware *data;
526 	const struct firmware *firmware;
527 	int ret, error, order;
528 	struct page *p;
529 	u64 data_size;
530 
531 	if (sev_get_firmware(dev, &firmware) == -ENOENT) {
532 		dev_dbg(dev, "No SEV firmware file present\n");
533 		return -1;
534 	}
535 
536 	/*
537 	 * SEV FW expects the physical address given to it to be 32
538 	 * byte aligned. Memory allocated has structure placed at the
539 	 * beginning followed by the firmware being passed to the SEV
540 	 * FW. Allocate enough memory for data structure + alignment
541 	 * padding + SEV FW.
542 	 */
543 	data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
544 
545 	order = get_order(firmware->size + data_size);
546 	p = alloc_pages(GFP_KERNEL, order);
547 	if (!p) {
548 		ret = -1;
549 		goto fw_err;
550 	}
551 
552 	/*
553 	 * Copy firmware data to a kernel allocated contiguous
554 	 * memory region.
555 	 */
556 	data = page_address(p);
557 	memcpy(page_address(p) + data_size, firmware->data, firmware->size);
558 
559 	data->address = __psp_pa(page_address(p) + data_size);
560 	data->len = firmware->size;
561 
562 	ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
563 	if (ret)
564 		dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
565 	else
566 		dev_info(dev, "SEV firmware update successful\n");
567 
568 	__free_pages(p, order);
569 
570 fw_err:
571 	release_firmware(firmware);
572 
573 	return ret;
574 }
575 
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)576 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
577 {
578 	struct sev_device *sev = psp_master->sev_data;
579 	struct sev_user_data_pek_cert_import input;
580 	struct sev_data_pek_cert_import *data;
581 	void *pek_blob, *oca_blob;
582 	int ret;
583 
584 	if (!writable)
585 		return -EPERM;
586 
587 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
588 		return -EFAULT;
589 
590 	data = kzalloc(sizeof(*data), GFP_KERNEL);
591 	if (!data)
592 		return -ENOMEM;
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 		ret = PTR_ERR(pek_blob);
598 		goto e_free;
599 	}
600 
601 	data->pek_cert_address = __psp_pa(pek_blob);
602 	data->pek_cert_len = input.pek_cert_len;
603 
604 	/* copy PEK certificate blobs from userspace */
605 	oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
606 	if (IS_ERR(oca_blob)) {
607 		ret = PTR_ERR(oca_blob);
608 		goto e_free_pek;
609 	}
610 
611 	data->oca_cert_address = __psp_pa(oca_blob);
612 	data->oca_cert_len = input.oca_cert_len;
613 
614 	/* If platform is not in INIT state then transition it to INIT */
615 	if (sev->state != SEV_STATE_INIT) {
616 		ret = __sev_platform_init_locked(&argp->error);
617 		if (ret)
618 			goto e_free_oca;
619 	}
620 
621 	ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, data, &argp->error);
622 
623 e_free_oca:
624 	kfree(oca_blob);
625 e_free_pek:
626 	kfree(pek_blob);
627 e_free:
628 	kfree(data);
629 	return ret;
630 }
631 
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)632 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
633 {
634 	struct sev_user_data_get_id2 input;
635 	struct sev_data_get_id *data;
636 	void __user *input_address;
637 	void *id_blob = NULL;
638 	int ret;
639 
640 	/* SEV GET_ID is available from SEV API v0.16 and up */
641 	if (!sev_version_greater_or_equal(0, 16))
642 		return -ENOTSUPP;
643 
644 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
645 		return -EFAULT;
646 
647 	input_address = (void __user *)input.address;
648 
649 	data = kzalloc(sizeof(*data), GFP_KERNEL);
650 	if (!data)
651 		return -ENOMEM;
652 
653 	if (input.address && input.length) {
654 		id_blob = kmalloc(input.length, GFP_KERNEL);
655 		if (!id_blob) {
656 			kfree(data);
657 			return -ENOMEM;
658 		}
659 
660 		data->address = __psp_pa(id_blob);
661 		data->len = input.length;
662 	}
663 
664 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
665 
666 	/*
667 	 * Firmware will return the length of the ID value (either the minimum
668 	 * required length or the actual length written), return it to the user.
669 	 */
670 	input.length = data->len;
671 
672 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
673 		ret = -EFAULT;
674 		goto e_free;
675 	}
676 
677 	if (id_blob) {
678 		if (copy_to_user(input_address, id_blob, data->len)) {
679 			ret = -EFAULT;
680 			goto e_free;
681 		}
682 	}
683 
684 e_free:
685 	kfree(id_blob);
686 	kfree(data);
687 
688 	return ret;
689 }
690 
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)691 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
692 {
693 	struct sev_data_get_id *data;
694 	u64 data_size, user_size;
695 	void *id_blob, *mem;
696 	int ret;
697 
698 	/* SEV GET_ID available from SEV API v0.16 and up */
699 	if (!sev_version_greater_or_equal(0, 16))
700 		return -ENOTSUPP;
701 
702 	/* SEV FW expects the buffer it fills with the ID to be
703 	 * 8-byte aligned. Memory allocated should be enough to
704 	 * hold data structure + alignment padding + memory
705 	 * where SEV FW writes the ID.
706 	 */
707 	data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
708 	user_size = sizeof(struct sev_user_data_get_id);
709 
710 	mem = kzalloc(data_size + user_size, GFP_KERNEL);
711 	if (!mem)
712 		return -ENOMEM;
713 
714 	data = mem;
715 	id_blob = mem + data_size;
716 
717 	data->address = __psp_pa(id_blob);
718 	data->len = user_size;
719 
720 	ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
721 	if (!ret) {
722 		if (copy_to_user((void __user *)argp->data, id_blob, data->len))
723 			ret = -EFAULT;
724 	}
725 
726 	kfree(mem);
727 
728 	return ret;
729 }
730 
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)731 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
732 {
733 	struct sev_device *sev = psp_master->sev_data;
734 	struct sev_user_data_pdh_cert_export input;
735 	void *pdh_blob = NULL, *cert_blob = NULL;
736 	struct sev_data_pdh_cert_export *data;
737 	void __user *input_cert_chain_address;
738 	void __user *input_pdh_cert_address;
739 	int ret;
740 
741 	/* If platform is not in INIT state then transition it to INIT. */
742 	if (sev->state != SEV_STATE_INIT) {
743 		if (!writable)
744 			return -EPERM;
745 
746 		ret = __sev_platform_init_locked(&argp->error);
747 		if (ret)
748 			return ret;
749 	}
750 
751 	if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
752 		return -EFAULT;
753 
754 	data = kzalloc(sizeof(*data), GFP_KERNEL);
755 	if (!data)
756 		return -ENOMEM;
757 
758 	/* Userspace wants to query the certificate length. */
759 	if (!input.pdh_cert_address ||
760 	    !input.pdh_cert_len ||
761 	    !input.cert_chain_address)
762 		goto cmd;
763 
764 	input_pdh_cert_address = (void __user *)input.pdh_cert_address;
765 	input_cert_chain_address = (void __user *)input.cert_chain_address;
766 
767 	/* Allocate a physically contiguous buffer to store the PDH blob. */
768 	if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) {
769 		ret = -EFAULT;
770 		goto e_free;
771 	}
772 
773 	/* Allocate a physically contiguous buffer to store the cert chain blob. */
774 	if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) {
775 		ret = -EFAULT;
776 		goto e_free;
777 	}
778 
779 	pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
780 	if (!pdh_blob) {
781 		ret = -ENOMEM;
782 		goto e_free;
783 	}
784 
785 	data->pdh_cert_address = __psp_pa(pdh_blob);
786 	data->pdh_cert_len = input.pdh_cert_len;
787 
788 	cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
789 	if (!cert_blob) {
790 		ret = -ENOMEM;
791 		goto e_free_pdh;
792 	}
793 
794 	data->cert_chain_address = __psp_pa(cert_blob);
795 	data->cert_chain_len = input.cert_chain_len;
796 
797 cmd:
798 	ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, data, &argp->error);
799 
800 	/* If we query the length, FW responded with expected data. */
801 	input.cert_chain_len = data->cert_chain_len;
802 	input.pdh_cert_len = data->pdh_cert_len;
803 
804 	if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
805 		ret = -EFAULT;
806 		goto e_free_cert;
807 	}
808 
809 	if (pdh_blob) {
810 		if (copy_to_user(input_pdh_cert_address,
811 				 pdh_blob, input.pdh_cert_len)) {
812 			ret = -EFAULT;
813 			goto e_free_cert;
814 		}
815 	}
816 
817 	if (cert_blob) {
818 		if (copy_to_user(input_cert_chain_address,
819 				 cert_blob, input.cert_chain_len))
820 			ret = -EFAULT;
821 	}
822 
823 e_free_cert:
824 	kfree(cert_blob);
825 e_free_pdh:
826 	kfree(pdh_blob);
827 e_free:
828 	kfree(data);
829 	return ret;
830 }
831 
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)832 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
833 {
834 	void __user *argp = (void __user *)arg;
835 	struct sev_issue_cmd input;
836 	int ret = -EFAULT;
837 	bool writable = file->f_mode & FMODE_WRITE;
838 
839 	if (!psp_master || !psp_master->sev_data)
840 		return -ENODEV;
841 
842 	if (ioctl != SEV_ISSUE_CMD)
843 		return -EINVAL;
844 
845 	if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
846 		return -EFAULT;
847 
848 	if (input.cmd > SEV_MAX)
849 		return -EINVAL;
850 
851 	mutex_lock(&sev_cmd_mutex);
852 
853 	switch (input.cmd) {
854 
855 	case SEV_FACTORY_RESET:
856 		ret = sev_ioctl_do_reset(&input, writable);
857 		break;
858 	case SEV_PLATFORM_STATUS:
859 		ret = sev_ioctl_do_platform_status(&input);
860 		break;
861 	case SEV_PEK_GEN:
862 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
863 		break;
864 	case SEV_PDH_GEN:
865 		ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
866 		break;
867 	case SEV_PEK_CSR:
868 		ret = sev_ioctl_do_pek_csr(&input, writable);
869 		break;
870 	case SEV_PEK_CERT_IMPORT:
871 		ret = sev_ioctl_do_pek_import(&input, writable);
872 		break;
873 	case SEV_PDH_CERT_EXPORT:
874 		ret = sev_ioctl_do_pdh_export(&input, writable);
875 		break;
876 	case SEV_GET_ID:
877 		pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
878 		ret = sev_ioctl_do_get_id(&input);
879 		break;
880 	case SEV_GET_ID2:
881 		ret = sev_ioctl_do_get_id2(&input);
882 		break;
883 	default:
884 		ret = -EINVAL;
885 		goto out;
886 	}
887 
888 	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
889 		ret = -EFAULT;
890 out:
891 	mutex_unlock(&sev_cmd_mutex);
892 
893 	return ret;
894 }
895 
896 static const struct file_operations sev_fops = {
897 	.owner	= THIS_MODULE,
898 	.unlocked_ioctl = sev_ioctl,
899 };
900 
sev_platform_status(struct sev_user_data_status * data,int * error)901 int sev_platform_status(struct sev_user_data_status *data, int *error)
902 {
903 	return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
904 }
905 EXPORT_SYMBOL_GPL(sev_platform_status);
906 
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)907 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
908 {
909 	return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
910 }
911 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
912 
sev_guest_activate(struct sev_data_activate * data,int * error)913 int sev_guest_activate(struct sev_data_activate *data, int *error)
914 {
915 	return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
916 }
917 EXPORT_SYMBOL_GPL(sev_guest_activate);
918 
sev_guest_decommission(struct sev_data_decommission * data,int * error)919 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
920 {
921 	return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
922 }
923 EXPORT_SYMBOL_GPL(sev_guest_decommission);
924 
sev_guest_df_flush(int * error)925 int sev_guest_df_flush(int *error)
926 {
927 	return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
928 }
929 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
930 
sev_exit(struct kref * ref)931 static void sev_exit(struct kref *ref)
932 {
933 	misc_deregister(&misc_dev->misc);
934 	kfree(misc_dev);
935 	misc_dev = NULL;
936 }
937 
sev_misc_init(struct sev_device * sev)938 static int sev_misc_init(struct sev_device *sev)
939 {
940 	struct device *dev = sev->dev;
941 	int ret;
942 
943 	/*
944 	 * SEV feature support can be detected on multiple devices but the SEV
945 	 * FW commands must be issued on the master. During probe, we do not
946 	 * know the master hence we create /dev/sev on the first device probe.
947 	 * sev_do_cmd() finds the right master device to which to issue the
948 	 * command to the firmware.
949 	 */
950 	if (!misc_dev) {
951 		struct miscdevice *misc;
952 
953 		misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
954 		if (!misc_dev)
955 			return -ENOMEM;
956 
957 		misc = &misc_dev->misc;
958 		misc->minor = MISC_DYNAMIC_MINOR;
959 		misc->name = DEVICE_NAME;
960 		misc->fops = &sev_fops;
961 
962 		ret = misc_register(misc);
963 		if (ret)
964 			return ret;
965 
966 		kref_init(&misc_dev->refcount);
967 	} else {
968 		kref_get(&misc_dev->refcount);
969 	}
970 
971 	init_waitqueue_head(&sev->int_queue);
972 	sev->misc = misc_dev;
973 	dev_dbg(dev, "registered SEV device\n");
974 
975 	return 0;
976 }
977 
sev_dev_init(struct psp_device * psp)978 int sev_dev_init(struct psp_device *psp)
979 {
980 	struct device *dev = psp->dev;
981 	struct sev_device *sev;
982 	int ret = -ENOMEM;
983 
984 	sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
985 	if (!sev)
986 		goto e_err;
987 
988 	psp->sev_data = sev;
989 
990 	sev->dev = dev;
991 	sev->psp = psp;
992 
993 	sev->io_regs = psp->io_regs;
994 
995 	sev->vdata = (struct sev_vdata *)psp->vdata->sev;
996 	if (!sev->vdata) {
997 		ret = -ENODEV;
998 		dev_err(dev, "sev: missing driver data\n");
999 		goto e_sev;
1000 	}
1001 
1002 	psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1003 
1004 	ret = sev_misc_init(sev);
1005 	if (ret)
1006 		goto e_irq;
1007 
1008 	dev_notice(dev, "sev enabled\n");
1009 
1010 	return 0;
1011 
1012 e_irq:
1013 	psp_clear_sev_irq_handler(psp);
1014 e_sev:
1015 	devm_kfree(dev, sev);
1016 e_err:
1017 	psp->sev_data = NULL;
1018 
1019 	dev_notice(dev, "sev initialization failed\n");
1020 
1021 	return ret;
1022 }
1023 
sev_firmware_shutdown(struct sev_device * sev)1024 static void sev_firmware_shutdown(struct sev_device *sev)
1025 {
1026 	sev_platform_shutdown(NULL);
1027 
1028 	if (sev_es_tmr) {
1029 		/* The TMR area was encrypted, flush it from the cache */
1030 		wbinvd_on_all_cpus();
1031 
1032 		free_pages((unsigned long)sev_es_tmr,
1033 			   get_order(SEV_ES_TMR_SIZE));
1034 		sev_es_tmr = NULL;
1035 	}
1036 }
1037 
sev_dev_destroy(struct psp_device * psp)1038 void sev_dev_destroy(struct psp_device *psp)
1039 {
1040 	struct sev_device *sev = psp->sev_data;
1041 
1042 	if (!sev)
1043 		return;
1044 
1045 	sev_firmware_shutdown(sev);
1046 
1047 	if (sev->misc)
1048 		kref_put(&misc_dev->refcount, sev_exit);
1049 
1050 	psp_clear_sev_irq_handler(psp);
1051 }
1052 
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)1053 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1054 				void *data, int *error)
1055 {
1056 	if (!filep || filep->f_op != &sev_fops)
1057 		return -EBADF;
1058 
1059 	return sev_do_cmd(cmd, data, error);
1060 }
1061 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1062 
sev_pci_init(void)1063 void sev_pci_init(void)
1064 {
1065 	struct sev_device *sev = psp_master->sev_data;
1066 	struct page *tmr_page;
1067 	int error, rc;
1068 
1069 	if (!sev)
1070 		return;
1071 
1072 	psp_timeout = psp_probe_timeout;
1073 
1074 	if (sev_get_api_version())
1075 		goto err;
1076 
1077 	if (sev_version_greater_or_equal(0, 15) &&
1078 	    sev_update_firmware(sev->dev) == 0)
1079 		sev_get_api_version();
1080 
1081 	/* Obtain the TMR memory area for SEV-ES use */
1082 	tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1083 	if (tmr_page) {
1084 		sev_es_tmr = page_address(tmr_page);
1085 	} else {
1086 		sev_es_tmr = NULL;
1087 		dev_warn(sev->dev,
1088 			 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1089 	}
1090 
1091 	/* Initialize the platform */
1092 	rc = sev_platform_init(&error);
1093 	if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1094 		/*
1095 		 * INIT command returned an integrity check failure
1096 		 * status code, meaning that firmware load and
1097 		 * validation of SEV related persistent data has
1098 		 * failed and persistent state has been erased.
1099 		 * Retrying INIT command here should succeed.
1100 		 */
1101 		dev_dbg(sev->dev, "SEV: retrying INIT command");
1102 		rc = sev_platform_init(&error);
1103 	}
1104 
1105 	if (rc) {
1106 		dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1107 		return;
1108 	}
1109 
1110 	dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1111 		 sev->api_minor, sev->build);
1112 
1113 	return;
1114 
1115 err:
1116 	psp_master->sev_data = NULL;
1117 }
1118 
sev_pci_exit(void)1119 void sev_pci_exit(void)
1120 {
1121 	struct sev_device *sev = psp_master->sev_data;
1122 
1123 	if (!sev)
1124 		return;
1125 
1126 	sev_firmware_shutdown(sev);
1127 }
1128