Loading...
Note: File does not exist in v4.17.
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#include <linux/fs.h>
26#include <linux/fs_struct.h>
27
28#include <asm/smp.h>
29
30#include "psp-dev.h"
31#include "sev-dev.h"
32
33#define DEVICE_NAME "sev"
34#define SEV_FW_FILE "amd/sev.fw"
35#define SEV_FW_NAME_SIZE 64
36
37static DEFINE_MUTEX(sev_cmd_mutex);
38static struct sev_misc_dev *misc_dev;
39
40static int psp_cmd_timeout = 100;
41module_param(psp_cmd_timeout, int, 0644);
42MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands");
43
44static int psp_probe_timeout = 5;
45module_param(psp_probe_timeout, int, 0644);
46MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe");
47
48static char *init_ex_path;
49module_param(init_ex_path, charp, 0444);
50MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX");
51
52static bool psp_init_on_probe = true;
53module_param(psp_init_on_probe, bool, 0444);
54MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it");
55
56MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
57MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
58MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
59
60static bool psp_dead;
61static int psp_timeout;
62
63/* Trusted Memory Region (TMR):
64 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator
65 * to allocate the memory, which will return aligned memory for the specified
66 * allocation order.
67 */
68#define SEV_ES_TMR_SIZE (1024 * 1024)
69static void *sev_es_tmr;
70
71/* INIT_EX NV Storage:
72 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page
73 * allocator to allocate the memory, which will return aligned memory for the
74 * specified allocation order.
75 */
76#define NV_LENGTH (32 * 1024)
77static void *sev_init_ex_buffer;
78
79static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
80{
81 struct sev_device *sev = psp_master->sev_data;
82
83 if (sev->api_major > maj)
84 return true;
85
86 if (sev->api_major == maj && sev->api_minor >= min)
87 return true;
88
89 return false;
90}
91
92static void sev_irq_handler(int irq, void *data, unsigned int status)
93{
94 struct sev_device *sev = data;
95 int reg;
96
97 /* Check if it is command completion: */
98 if (!(status & SEV_CMD_COMPLETE))
99 return;
100
101 /* Check if it is SEV command completion: */
102 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
103 if (reg & PSP_CMDRESP_RESP) {
104 sev->int_rcvd = 1;
105 wake_up(&sev->int_queue);
106 }
107}
108
109static int sev_wait_cmd_ioc(struct sev_device *sev,
110 unsigned int *reg, unsigned int timeout)
111{
112 int ret;
113
114 ret = wait_event_timeout(sev->int_queue,
115 sev->int_rcvd, timeout * HZ);
116 if (!ret)
117 return -ETIMEDOUT;
118
119 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
120
121 return 0;
122}
123
124static int sev_cmd_buffer_len(int cmd)
125{
126 switch (cmd) {
127 case SEV_CMD_INIT: return sizeof(struct sev_data_init);
128 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex);
129 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status);
130 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr);
131 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import);
132 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export);
133 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start);
134 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data);
135 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa);
136 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish);
137 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure);
138 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate);
139 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate);
140 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission);
141 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status);
142 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg);
143 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg);
144 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start);
145 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data);
146 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa);
147 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish);
148 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start);
149 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish);
150 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data);
151 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa);
152 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret);
153 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware);
154 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id);
155 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report);
156 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel);
157 default: return 0;
158 }
159
160 return 0;
161}
162
163static void *sev_fw_alloc(unsigned long len)
164{
165 struct page *page;
166
167 page = alloc_pages(GFP_KERNEL, get_order(len));
168 if (!page)
169 return NULL;
170
171 return page_address(page);
172}
173
174static struct file *open_file_as_root(const char *filename, int flags, umode_t mode)
175{
176 struct file *fp;
177 struct path root;
178 struct cred *cred;
179 const struct cred *old_cred;
180
181 task_lock(&init_task);
182 get_fs_root(init_task.fs, &root);
183 task_unlock(&init_task);
184
185 cred = prepare_creds();
186 if (!cred)
187 return ERR_PTR(-ENOMEM);
188 cred->fsuid = GLOBAL_ROOT_UID;
189 old_cred = override_creds(cred);
190
191 fp = file_open_root(&root, filename, flags, mode);
192 path_put(&root);
193
194 revert_creds(old_cred);
195
196 return fp;
197}
198
199static int sev_read_init_ex_file(void)
200{
201 struct sev_device *sev = psp_master->sev_data;
202 struct file *fp;
203 ssize_t nread;
204
205 lockdep_assert_held(&sev_cmd_mutex);
206
207 if (!sev_init_ex_buffer)
208 return -EOPNOTSUPP;
209
210 fp = open_file_as_root(init_ex_path, O_RDONLY, 0);
211 if (IS_ERR(fp)) {
212 int ret = PTR_ERR(fp);
213
214 if (ret == -ENOENT) {
215 dev_info(sev->dev,
216 "SEV: %s does not exist and will be created later.\n",
217 init_ex_path);
218 ret = 0;
219 } else {
220 dev_err(sev->dev,
221 "SEV: could not open %s for read, error %d\n",
222 init_ex_path, ret);
223 }
224 return ret;
225 }
226
227 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL);
228 if (nread != NV_LENGTH) {
229 dev_info(sev->dev,
230 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n",
231 NV_LENGTH, nread);
232 }
233
234 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread);
235 filp_close(fp, NULL);
236
237 return 0;
238}
239
240static int sev_write_init_ex_file(void)
241{
242 struct sev_device *sev = psp_master->sev_data;
243 struct file *fp;
244 loff_t offset = 0;
245 ssize_t nwrite;
246
247 lockdep_assert_held(&sev_cmd_mutex);
248
249 if (!sev_init_ex_buffer)
250 return 0;
251
252 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600);
253 if (IS_ERR(fp)) {
254 int ret = PTR_ERR(fp);
255
256 dev_err(sev->dev,
257 "SEV: could not open file for write, error %d\n",
258 ret);
259 return ret;
260 }
261
262 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset);
263 vfs_fsync(fp, 0);
264 filp_close(fp, NULL);
265
266 if (nwrite != NV_LENGTH) {
267 dev_err(sev->dev,
268 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n",
269 NV_LENGTH, nwrite);
270 return -EIO;
271 }
272
273 dev_dbg(sev->dev, "SEV: write successful to NV file\n");
274
275 return 0;
276}
277
278static int sev_write_init_ex_file_if_required(int cmd_id)
279{
280 lockdep_assert_held(&sev_cmd_mutex);
281
282 if (!sev_init_ex_buffer)
283 return 0;
284
285 /*
286 * Only a few platform commands modify the SPI/NV area, but none of the
287 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN,
288 * PEK_CERT_IMPORT, and PDH_GEN do.
289 */
290 switch (cmd_id) {
291 case SEV_CMD_FACTORY_RESET:
292 case SEV_CMD_INIT_EX:
293 case SEV_CMD_PDH_GEN:
294 case SEV_CMD_PEK_CERT_IMPORT:
295 case SEV_CMD_PEK_GEN:
296 break;
297 default:
298 return 0;
299 }
300
301 return sev_write_init_ex_file();
302}
303
304static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
305{
306 struct psp_device *psp = psp_master;
307 struct sev_device *sev;
308 unsigned int phys_lsb, phys_msb;
309 unsigned int reg, ret = 0;
310 int buf_len;
311
312 if (!psp || !psp->sev_data)
313 return -ENODEV;
314
315 if (psp_dead)
316 return -EBUSY;
317
318 sev = psp->sev_data;
319
320 buf_len = sev_cmd_buffer_len(cmd);
321 if (WARN_ON_ONCE(!data != !buf_len))
322 return -EINVAL;
323
324 /*
325 * Copy the incoming data to driver's scratch buffer as __pa() will not
326 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
327 * physically contiguous.
328 */
329 if (data)
330 memcpy(sev->cmd_buf, data, buf_len);
331
332 /* Get the physical address of the command buffer */
333 phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0;
334 phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0;
335
336 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
337 cmd, phys_msb, phys_lsb, psp_timeout);
338
339 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data,
340 buf_len, false);
341
342 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
343 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
344
345 sev->int_rcvd = 0;
346
347 reg = cmd;
348 reg <<= SEV_CMDRESP_CMD_SHIFT;
349 reg |= SEV_CMDRESP_IOC;
350 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
351
352 /* wait for command completion */
353 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout);
354 if (ret) {
355 if (psp_ret)
356 *psp_ret = 0;
357
358 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
359 psp_dead = true;
360
361 return ret;
362 }
363
364 psp_timeout = psp_cmd_timeout;
365
366 if (psp_ret)
367 *psp_ret = reg & PSP_CMDRESP_ERR_MASK;
368
369 if (reg & PSP_CMDRESP_ERR_MASK) {
370 dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
371 cmd, reg & PSP_CMDRESP_ERR_MASK);
372 ret = -EIO;
373 } else {
374 ret = sev_write_init_ex_file_if_required(cmd);
375 }
376
377 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
378 buf_len, false);
379
380 /*
381 * Copy potential output from the PSP back to data. Do this even on
382 * failure in case the caller wants to glean something from the error.
383 */
384 if (data)
385 memcpy(data, sev->cmd_buf, buf_len);
386
387 return ret;
388}
389
390static int sev_do_cmd(int cmd, void *data, int *psp_ret)
391{
392 int rc;
393
394 mutex_lock(&sev_cmd_mutex);
395 rc = __sev_do_cmd_locked(cmd, data, psp_ret);
396 mutex_unlock(&sev_cmd_mutex);
397
398 return rc;
399}
400
401static int __sev_init_locked(int *error)
402{
403 struct sev_data_init data;
404
405 memset(&data, 0, sizeof(data));
406 if (sev_es_tmr) {
407 /*
408 * Do not include the encryption mask on the physical
409 * address of the TMR (firmware should clear it anyway).
410 */
411 data.tmr_address = __pa(sev_es_tmr);
412
413 data.flags |= SEV_INIT_FLAGS_SEV_ES;
414 data.tmr_len = SEV_ES_TMR_SIZE;
415 }
416
417 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
418}
419
420static int __sev_init_ex_locked(int *error)
421{
422 struct sev_data_init_ex data;
423
424 memset(&data, 0, sizeof(data));
425 data.length = sizeof(data);
426 data.nv_address = __psp_pa(sev_init_ex_buffer);
427 data.nv_len = NV_LENGTH;
428
429 if (sev_es_tmr) {
430 /*
431 * Do not include the encryption mask on the physical
432 * address of the TMR (firmware should clear it anyway).
433 */
434 data.tmr_address = __pa(sev_es_tmr);
435
436 data.flags |= SEV_INIT_FLAGS_SEV_ES;
437 data.tmr_len = SEV_ES_TMR_SIZE;
438 }
439
440 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error);
441}
442
443static int __sev_platform_init_locked(int *error)
444{
445 struct psp_device *psp = psp_master;
446 struct sev_device *sev;
447 int rc = 0, psp_ret = -1;
448 int (*init_function)(int *error);
449
450 if (!psp || !psp->sev_data)
451 return -ENODEV;
452
453 sev = psp->sev_data;
454
455 if (sev->state == SEV_STATE_INIT)
456 return 0;
457
458 if (sev_init_ex_buffer) {
459 init_function = __sev_init_ex_locked;
460 rc = sev_read_init_ex_file();
461 if (rc)
462 return rc;
463 } else {
464 init_function = __sev_init_locked;
465 }
466
467 rc = init_function(&psp_ret);
468 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) {
469 /*
470 * Initialization command returned an integrity check failure
471 * status code, meaning that firmware load and validation of SEV
472 * related persistent data has failed. Retrying the
473 * initialization function should succeed by replacing the state
474 * with a reset state.
475 */
476 dev_err(sev->dev, "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state.");
477 rc = init_function(&psp_ret);
478 }
479 if (error)
480 *error = psp_ret;
481
482 if (rc)
483 return rc;
484
485 sev->state = SEV_STATE_INIT;
486
487 /* Prepare for first SEV guest launch after INIT */
488 wbinvd_on_all_cpus();
489 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
490 if (rc)
491 return rc;
492
493 dev_dbg(sev->dev, "SEV firmware initialized\n");
494
495 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
496 sev->api_minor, sev->build);
497
498 return 0;
499}
500
501int sev_platform_init(int *error)
502{
503 int rc;
504
505 mutex_lock(&sev_cmd_mutex);
506 rc = __sev_platform_init_locked(error);
507 mutex_unlock(&sev_cmd_mutex);
508
509 return rc;
510}
511EXPORT_SYMBOL_GPL(sev_platform_init);
512
513static int __sev_platform_shutdown_locked(int *error)
514{
515 struct sev_device *sev = psp_master->sev_data;
516 int ret;
517
518 if (!sev || sev->state == SEV_STATE_UNINIT)
519 return 0;
520
521 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
522 if (ret)
523 return ret;
524
525 sev->state = SEV_STATE_UNINIT;
526 dev_dbg(sev->dev, "SEV firmware shutdown\n");
527
528 return ret;
529}
530
531static int sev_platform_shutdown(int *error)
532{
533 int rc;
534
535 mutex_lock(&sev_cmd_mutex);
536 rc = __sev_platform_shutdown_locked(NULL);
537 mutex_unlock(&sev_cmd_mutex);
538
539 return rc;
540}
541
542static int sev_get_platform_state(int *state, int *error)
543{
544 struct sev_user_data_status data;
545 int rc;
546
547 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
548 if (rc)
549 return rc;
550
551 *state = data.state;
552 return rc;
553}
554
555static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
556{
557 int state, rc;
558
559 if (!writable)
560 return -EPERM;
561
562 /*
563 * The SEV spec requires that FACTORY_RESET must be issued in
564 * UNINIT state. Before we go further lets check if any guest is
565 * active.
566 *
567 * If FW is in WORKING state then deny the request otherwise issue
568 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
569 *
570 */
571 rc = sev_get_platform_state(&state, &argp->error);
572 if (rc)
573 return rc;
574
575 if (state == SEV_STATE_WORKING)
576 return -EBUSY;
577
578 if (state == SEV_STATE_INIT) {
579 rc = __sev_platform_shutdown_locked(&argp->error);
580 if (rc)
581 return rc;
582 }
583
584 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
585}
586
587static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
588{
589 struct sev_user_data_status data;
590 int ret;
591
592 memset(&data, 0, sizeof(data));
593
594 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
595 if (ret)
596 return ret;
597
598 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
599 ret = -EFAULT;
600
601 return ret;
602}
603
604static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
605{
606 struct sev_device *sev = psp_master->sev_data;
607 int rc;
608
609 if (!writable)
610 return -EPERM;
611
612 if (sev->state == SEV_STATE_UNINIT) {
613 rc = __sev_platform_init_locked(&argp->error);
614 if (rc)
615 return rc;
616 }
617
618 return __sev_do_cmd_locked(cmd, NULL, &argp->error);
619}
620
621static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
622{
623 struct sev_device *sev = psp_master->sev_data;
624 struct sev_user_data_pek_csr input;
625 struct sev_data_pek_csr data;
626 void __user *input_address;
627 void *blob = NULL;
628 int ret;
629
630 if (!writable)
631 return -EPERM;
632
633 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
634 return -EFAULT;
635
636 memset(&data, 0, sizeof(data));
637
638 /* userspace wants to query CSR length */
639 if (!input.address || !input.length)
640 goto cmd;
641
642 /* allocate a physically contiguous buffer to store the CSR blob */
643 input_address = (void __user *)input.address;
644 if (input.length > SEV_FW_BLOB_MAX_SIZE)
645 return -EFAULT;
646
647 blob = kzalloc(input.length, GFP_KERNEL);
648 if (!blob)
649 return -ENOMEM;
650
651 data.address = __psp_pa(blob);
652 data.len = input.length;
653
654cmd:
655 if (sev->state == SEV_STATE_UNINIT) {
656 ret = __sev_platform_init_locked(&argp->error);
657 if (ret)
658 goto e_free_blob;
659 }
660
661 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
662
663 /* If we query the CSR length, FW responded with expected data. */
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_blob;
669 }
670
671 if (blob) {
672 if (copy_to_user(input_address, blob, input.length))
673 ret = -EFAULT;
674 }
675
676e_free_blob:
677 kfree(blob);
678 return ret;
679}
680
681void *psp_copy_user_blob(u64 uaddr, u32 len)
682{
683 if (!uaddr || !len)
684 return ERR_PTR(-EINVAL);
685
686 /* verify that blob length does not exceed our limit */
687 if (len > SEV_FW_BLOB_MAX_SIZE)
688 return ERR_PTR(-EINVAL);
689
690 return memdup_user((void __user *)uaddr, len);
691}
692EXPORT_SYMBOL_GPL(psp_copy_user_blob);
693
694static int sev_get_api_version(void)
695{
696 struct sev_device *sev = psp_master->sev_data;
697 struct sev_user_data_status status;
698 int error = 0, ret;
699
700 ret = sev_platform_status(&status, &error);
701 if (ret) {
702 dev_err(sev->dev,
703 "SEV: failed to get status. Error: %#x\n", error);
704 return 1;
705 }
706
707 sev->api_major = status.api_major;
708 sev->api_minor = status.api_minor;
709 sev->build = status.build;
710 sev->state = status.state;
711
712 return 0;
713}
714
715static int sev_get_firmware(struct device *dev,
716 const struct firmware **firmware)
717{
718 char fw_name_specific[SEV_FW_NAME_SIZE];
719 char fw_name_subset[SEV_FW_NAME_SIZE];
720
721 snprintf(fw_name_specific, sizeof(fw_name_specific),
722 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
723 boot_cpu_data.x86, boot_cpu_data.x86_model);
724
725 snprintf(fw_name_subset, sizeof(fw_name_subset),
726 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
727 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
728
729 /* Check for SEV FW for a particular model.
730 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
731 *
732 * or
733 *
734 * Check for SEV FW common to a subset of models.
735 * Ex. amd_sev_fam17h_model0xh.sbin for
736 * Family 17h Model 00h -- Family 17h Model 0Fh
737 *
738 * or
739 *
740 * Fall-back to using generic name: sev.fw
741 */
742 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
743 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
744 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
745 return 0;
746
747 return -ENOENT;
748}
749
750/* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
751static int sev_update_firmware(struct device *dev)
752{
753 struct sev_data_download_firmware *data;
754 const struct firmware *firmware;
755 int ret, error, order;
756 struct page *p;
757 u64 data_size;
758
759 if (!sev_version_greater_or_equal(0, 15)) {
760 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n");
761 return -1;
762 }
763
764 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
765 dev_dbg(dev, "No SEV firmware file present\n");
766 return -1;
767 }
768
769 /*
770 * SEV FW expects the physical address given to it to be 32
771 * byte aligned. Memory allocated has structure placed at the
772 * beginning followed by the firmware being passed to the SEV
773 * FW. Allocate enough memory for data structure + alignment
774 * padding + SEV FW.
775 */
776 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
777
778 order = get_order(firmware->size + data_size);
779 p = alloc_pages(GFP_KERNEL, order);
780 if (!p) {
781 ret = -1;
782 goto fw_err;
783 }
784
785 /*
786 * Copy firmware data to a kernel allocated contiguous
787 * memory region.
788 */
789 data = page_address(p);
790 memcpy(page_address(p) + data_size, firmware->data, firmware->size);
791
792 data->address = __psp_pa(page_address(p) + data_size);
793 data->len = firmware->size;
794
795 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
796
797 /*
798 * A quirk for fixing the committed TCB version, when upgrading from
799 * earlier firmware version than 1.50.
800 */
801 if (!ret && !sev_version_greater_or_equal(1, 50))
802 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
803
804 if (ret)
805 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
806 else
807 dev_info(dev, "SEV firmware update successful\n");
808
809 __free_pages(p, order);
810
811fw_err:
812 release_firmware(firmware);
813
814 return ret;
815}
816
817static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
818{
819 struct sev_device *sev = psp_master->sev_data;
820 struct sev_user_data_pek_cert_import input;
821 struct sev_data_pek_cert_import data;
822 void *pek_blob, *oca_blob;
823 int ret;
824
825 if (!writable)
826 return -EPERM;
827
828 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
829 return -EFAULT;
830
831 /* copy PEK certificate blobs from userspace */
832 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
833 if (IS_ERR(pek_blob))
834 return PTR_ERR(pek_blob);
835
836 data.reserved = 0;
837 data.pek_cert_address = __psp_pa(pek_blob);
838 data.pek_cert_len = input.pek_cert_len;
839
840 /* copy PEK certificate blobs from userspace */
841 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
842 if (IS_ERR(oca_blob)) {
843 ret = PTR_ERR(oca_blob);
844 goto e_free_pek;
845 }
846
847 data.oca_cert_address = __psp_pa(oca_blob);
848 data.oca_cert_len = input.oca_cert_len;
849
850 /* If platform is not in INIT state then transition it to INIT */
851 if (sev->state != SEV_STATE_INIT) {
852 ret = __sev_platform_init_locked(&argp->error);
853 if (ret)
854 goto e_free_oca;
855 }
856
857 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
858
859e_free_oca:
860 kfree(oca_blob);
861e_free_pek:
862 kfree(pek_blob);
863 return ret;
864}
865
866static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
867{
868 struct sev_user_data_get_id2 input;
869 struct sev_data_get_id data;
870 void __user *input_address;
871 void *id_blob = NULL;
872 int ret;
873
874 /* SEV GET_ID is available from SEV API v0.16 and up */
875 if (!sev_version_greater_or_equal(0, 16))
876 return -ENOTSUPP;
877
878 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
879 return -EFAULT;
880
881 input_address = (void __user *)input.address;
882
883 if (input.address && input.length) {
884 id_blob = kzalloc(input.length, GFP_KERNEL);
885 if (!id_blob)
886 return -ENOMEM;
887
888 data.address = __psp_pa(id_blob);
889 data.len = input.length;
890 } else {
891 data.address = 0;
892 data.len = 0;
893 }
894
895 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
896
897 /*
898 * Firmware will return the length of the ID value (either the minimum
899 * required length or the actual length written), return it to the user.
900 */
901 input.length = data.len;
902
903 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
904 ret = -EFAULT;
905 goto e_free;
906 }
907
908 if (id_blob) {
909 if (copy_to_user(input_address, id_blob, data.len)) {
910 ret = -EFAULT;
911 goto e_free;
912 }
913 }
914
915e_free:
916 kfree(id_blob);
917
918 return ret;
919}
920
921static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
922{
923 struct sev_data_get_id *data;
924 u64 data_size, user_size;
925 void *id_blob, *mem;
926 int ret;
927
928 /* SEV GET_ID available from SEV API v0.16 and up */
929 if (!sev_version_greater_or_equal(0, 16))
930 return -ENOTSUPP;
931
932 /* SEV FW expects the buffer it fills with the ID to be
933 * 8-byte aligned. Memory allocated should be enough to
934 * hold data structure + alignment padding + memory
935 * where SEV FW writes the ID.
936 */
937 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
938 user_size = sizeof(struct sev_user_data_get_id);
939
940 mem = kzalloc(data_size + user_size, GFP_KERNEL);
941 if (!mem)
942 return -ENOMEM;
943
944 data = mem;
945 id_blob = mem + data_size;
946
947 data->address = __psp_pa(id_blob);
948 data->len = user_size;
949
950 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
951 if (!ret) {
952 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
953 ret = -EFAULT;
954 }
955
956 kfree(mem);
957
958 return ret;
959}
960
961static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
962{
963 struct sev_device *sev = psp_master->sev_data;
964 struct sev_user_data_pdh_cert_export input;
965 void *pdh_blob = NULL, *cert_blob = NULL;
966 struct sev_data_pdh_cert_export data;
967 void __user *input_cert_chain_address;
968 void __user *input_pdh_cert_address;
969 int ret;
970
971 /* If platform is not in INIT state then transition it to INIT. */
972 if (sev->state != SEV_STATE_INIT) {
973 if (!writable)
974 return -EPERM;
975
976 ret = __sev_platform_init_locked(&argp->error);
977 if (ret)
978 return ret;
979 }
980
981 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
982 return -EFAULT;
983
984 memset(&data, 0, sizeof(data));
985
986 /* Userspace wants to query the certificate length. */
987 if (!input.pdh_cert_address ||
988 !input.pdh_cert_len ||
989 !input.cert_chain_address)
990 goto cmd;
991
992 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
993 input_cert_chain_address = (void __user *)input.cert_chain_address;
994
995 /* Allocate a physically contiguous buffer to store the PDH blob. */
996 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
997 return -EFAULT;
998
999 /* Allocate a physically contiguous buffer to store the cert chain blob. */
1000 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
1001 return -EFAULT;
1002
1003 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
1004 if (!pdh_blob)
1005 return -ENOMEM;
1006
1007 data.pdh_cert_address = __psp_pa(pdh_blob);
1008 data.pdh_cert_len = input.pdh_cert_len;
1009
1010 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
1011 if (!cert_blob) {
1012 ret = -ENOMEM;
1013 goto e_free_pdh;
1014 }
1015
1016 data.cert_chain_address = __psp_pa(cert_blob);
1017 data.cert_chain_len = input.cert_chain_len;
1018
1019cmd:
1020 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
1021
1022 /* If we query the length, FW responded with expected data. */
1023 input.cert_chain_len = data.cert_chain_len;
1024 input.pdh_cert_len = data.pdh_cert_len;
1025
1026 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
1027 ret = -EFAULT;
1028 goto e_free_cert;
1029 }
1030
1031 if (pdh_blob) {
1032 if (copy_to_user(input_pdh_cert_address,
1033 pdh_blob, input.pdh_cert_len)) {
1034 ret = -EFAULT;
1035 goto e_free_cert;
1036 }
1037 }
1038
1039 if (cert_blob) {
1040 if (copy_to_user(input_cert_chain_address,
1041 cert_blob, input.cert_chain_len))
1042 ret = -EFAULT;
1043 }
1044
1045e_free_cert:
1046 kfree(cert_blob);
1047e_free_pdh:
1048 kfree(pdh_blob);
1049 return ret;
1050}
1051
1052static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
1053{
1054 void __user *argp = (void __user *)arg;
1055 struct sev_issue_cmd input;
1056 int ret = -EFAULT;
1057 bool writable = file->f_mode & FMODE_WRITE;
1058
1059 if (!psp_master || !psp_master->sev_data)
1060 return -ENODEV;
1061
1062 if (ioctl != SEV_ISSUE_CMD)
1063 return -EINVAL;
1064
1065 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
1066 return -EFAULT;
1067
1068 if (input.cmd > SEV_MAX)
1069 return -EINVAL;
1070
1071 mutex_lock(&sev_cmd_mutex);
1072
1073 switch (input.cmd) {
1074
1075 case SEV_FACTORY_RESET:
1076 ret = sev_ioctl_do_reset(&input, writable);
1077 break;
1078 case SEV_PLATFORM_STATUS:
1079 ret = sev_ioctl_do_platform_status(&input);
1080 break;
1081 case SEV_PEK_GEN:
1082 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
1083 break;
1084 case SEV_PDH_GEN:
1085 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
1086 break;
1087 case SEV_PEK_CSR:
1088 ret = sev_ioctl_do_pek_csr(&input, writable);
1089 break;
1090 case SEV_PEK_CERT_IMPORT:
1091 ret = sev_ioctl_do_pek_import(&input, writable);
1092 break;
1093 case SEV_PDH_CERT_EXPORT:
1094 ret = sev_ioctl_do_pdh_export(&input, writable);
1095 break;
1096 case SEV_GET_ID:
1097 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
1098 ret = sev_ioctl_do_get_id(&input);
1099 break;
1100 case SEV_GET_ID2:
1101 ret = sev_ioctl_do_get_id2(&input);
1102 break;
1103 default:
1104 ret = -EINVAL;
1105 goto out;
1106 }
1107
1108 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
1109 ret = -EFAULT;
1110out:
1111 mutex_unlock(&sev_cmd_mutex);
1112
1113 return ret;
1114}
1115
1116static const struct file_operations sev_fops = {
1117 .owner = THIS_MODULE,
1118 .unlocked_ioctl = sev_ioctl,
1119};
1120
1121int sev_platform_status(struct sev_user_data_status *data, int *error)
1122{
1123 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
1124}
1125EXPORT_SYMBOL_GPL(sev_platform_status);
1126
1127int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
1128{
1129 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
1130}
1131EXPORT_SYMBOL_GPL(sev_guest_deactivate);
1132
1133int sev_guest_activate(struct sev_data_activate *data, int *error)
1134{
1135 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
1136}
1137EXPORT_SYMBOL_GPL(sev_guest_activate);
1138
1139int sev_guest_decommission(struct sev_data_decommission *data, int *error)
1140{
1141 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
1142}
1143EXPORT_SYMBOL_GPL(sev_guest_decommission);
1144
1145int sev_guest_df_flush(int *error)
1146{
1147 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
1148}
1149EXPORT_SYMBOL_GPL(sev_guest_df_flush);
1150
1151static void sev_exit(struct kref *ref)
1152{
1153 misc_deregister(&misc_dev->misc);
1154 kfree(misc_dev);
1155 misc_dev = NULL;
1156}
1157
1158static int sev_misc_init(struct sev_device *sev)
1159{
1160 struct device *dev = sev->dev;
1161 int ret;
1162
1163 /*
1164 * SEV feature support can be detected on multiple devices but the SEV
1165 * FW commands must be issued on the master. During probe, we do not
1166 * know the master hence we create /dev/sev on the first device probe.
1167 * sev_do_cmd() finds the right master device to which to issue the
1168 * command to the firmware.
1169 */
1170 if (!misc_dev) {
1171 struct miscdevice *misc;
1172
1173 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
1174 if (!misc_dev)
1175 return -ENOMEM;
1176
1177 misc = &misc_dev->misc;
1178 misc->minor = MISC_DYNAMIC_MINOR;
1179 misc->name = DEVICE_NAME;
1180 misc->fops = &sev_fops;
1181
1182 ret = misc_register(misc);
1183 if (ret)
1184 return ret;
1185
1186 kref_init(&misc_dev->refcount);
1187 } else {
1188 kref_get(&misc_dev->refcount);
1189 }
1190
1191 init_waitqueue_head(&sev->int_queue);
1192 sev->misc = misc_dev;
1193 dev_dbg(dev, "registered SEV device\n");
1194
1195 return 0;
1196}
1197
1198int sev_dev_init(struct psp_device *psp)
1199{
1200 struct device *dev = psp->dev;
1201 struct sev_device *sev;
1202 int ret = -ENOMEM;
1203
1204 if (!boot_cpu_has(X86_FEATURE_SEV)) {
1205 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
1206 return 0;
1207 }
1208
1209 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
1210 if (!sev)
1211 goto e_err;
1212
1213 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
1214 if (!sev->cmd_buf)
1215 goto e_sev;
1216
1217 psp->sev_data = sev;
1218
1219 sev->dev = dev;
1220 sev->psp = psp;
1221
1222 sev->io_regs = psp->io_regs;
1223
1224 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
1225 if (!sev->vdata) {
1226 ret = -ENODEV;
1227 dev_err(dev, "sev: missing driver data\n");
1228 goto e_buf;
1229 }
1230
1231 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1232
1233 ret = sev_misc_init(sev);
1234 if (ret)
1235 goto e_irq;
1236
1237 dev_notice(dev, "sev enabled\n");
1238
1239 return 0;
1240
1241e_irq:
1242 psp_clear_sev_irq_handler(psp);
1243e_buf:
1244 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1245e_sev:
1246 devm_kfree(dev, sev);
1247e_err:
1248 psp->sev_data = NULL;
1249
1250 dev_notice(dev, "sev initialization failed\n");
1251
1252 return ret;
1253}
1254
1255static void sev_firmware_shutdown(struct sev_device *sev)
1256{
1257 sev_platform_shutdown(NULL);
1258
1259 if (sev_es_tmr) {
1260 /* The TMR area was encrypted, flush it from the cache */
1261 wbinvd_on_all_cpus();
1262
1263 free_pages((unsigned long)sev_es_tmr,
1264 get_order(SEV_ES_TMR_SIZE));
1265 sev_es_tmr = NULL;
1266 }
1267
1268 if (sev_init_ex_buffer) {
1269 free_pages((unsigned long)sev_init_ex_buffer,
1270 get_order(NV_LENGTH));
1271 sev_init_ex_buffer = NULL;
1272 }
1273}
1274
1275void sev_dev_destroy(struct psp_device *psp)
1276{
1277 struct sev_device *sev = psp->sev_data;
1278
1279 if (!sev)
1280 return;
1281
1282 sev_firmware_shutdown(sev);
1283
1284 if (sev->misc)
1285 kref_put(&misc_dev->refcount, sev_exit);
1286
1287 psp_clear_sev_irq_handler(psp);
1288}
1289
1290int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1291 void *data, int *error)
1292{
1293 if (!filep || filep->f_op != &sev_fops)
1294 return -EBADF;
1295
1296 return sev_do_cmd(cmd, data, error);
1297}
1298EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1299
1300void sev_pci_init(void)
1301{
1302 struct sev_device *sev = psp_master->sev_data;
1303 int error, rc;
1304
1305 if (!sev)
1306 return;
1307
1308 psp_timeout = psp_probe_timeout;
1309
1310 if (sev_get_api_version())
1311 goto err;
1312
1313 if (sev_update_firmware(sev->dev) == 0)
1314 sev_get_api_version();
1315
1316 /* If an init_ex_path is provided rely on INIT_EX for PSP initialization
1317 * instead of INIT.
1318 */
1319 if (init_ex_path) {
1320 sev_init_ex_buffer = sev_fw_alloc(NV_LENGTH);
1321 if (!sev_init_ex_buffer) {
1322 dev_err(sev->dev,
1323 "SEV: INIT_EX NV memory allocation failed\n");
1324 goto err;
1325 }
1326 }
1327
1328 /* Obtain the TMR memory area for SEV-ES use */
1329 sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
1330 if (!sev_es_tmr)
1331 dev_warn(sev->dev,
1332 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1333
1334 if (!psp_init_on_probe)
1335 return;
1336
1337 /* Initialize the platform */
1338 rc = sev_platform_init(&error);
1339 if (rc)
1340 dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n",
1341 error, rc);
1342
1343 return;
1344
1345err:
1346 psp_master->sev_data = NULL;
1347}
1348
1349void sev_pci_exit(void)
1350{
1351 struct sev_device *sev = psp_master->sev_data;
1352
1353 if (!sev)
1354 return;
1355
1356 sev_firmware_shutdown(sev);
1357}