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 #include <asm/cacheflush.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 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */
47 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */
48 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */
49
50 static bool psp_dead;
51 static int psp_timeout;
52
53 /* Trusted Memory Region (TMR):
54 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator
55 * to allocate the memory, which will return aligned memory for the specified
56 * allocation order.
57 */
58 #define SEV_ES_TMR_SIZE (1024 * 1024)
59 static void *sev_es_tmr;
60
sev_version_greater_or_equal(u8 maj, u8 min)61 static inline bool sev_version_greater_or_equal(u8 maj, u8 min)
62 {
63 struct sev_device *sev = psp_master->sev_data;
64
65 if (sev->api_major > maj)
66 return true;
67
68 if (sev->api_major == maj && sev->api_minor >= min)
69 return true;
70
71 return false;
72 }
73
sev_irq_handler(int irq, void *data, unsigned int status)74 static void sev_irq_handler(int irq, void *data, unsigned int status)
75 {
76 struct sev_device *sev = data;
77 int reg;
78
79 /* Check if it is command completion: */
80 if (!(status & SEV_CMD_COMPLETE))
81 return;
82
83 /* Check if it is SEV command completion: */
84 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
85 if (reg & PSP_CMDRESP_RESP) {
86 sev->int_rcvd = 1;
87 wake_up(&sev->int_queue);
88 }
89 }
90
sev_wait_cmd_ioc(struct sev_device *sev, unsigned int *reg, unsigned int timeout)91 static int sev_wait_cmd_ioc(struct sev_device *sev,
92 unsigned int *reg, unsigned int timeout)
93 {
94 int ret;
95
96 ret = wait_event_timeout(sev->int_queue,
97 sev->int_rcvd, timeout * HZ);
98 if (!ret)
99 return -ETIMEDOUT;
100
101 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg);
102
103 return 0;
104 }
105
sev_cmd_buffer_len(int cmd)106 static int sev_cmd_buffer_len(int cmd)
107 {
108 switch (cmd) {
109 case SEV_CMD_INIT: return sizeof(struct sev_data_init);
110 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status);
111 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr);
112 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import);
113 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export);
114 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start);
115 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data);
116 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa);
117 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish);
118 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure);
119 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate);
120 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate);
121 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission);
122 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status);
123 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg);
124 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg);
125 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start);
126 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data);
127 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa);
128 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish);
129 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start);
130 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish);
131 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data);
132 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa);
133 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret);
134 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware);
135 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id);
136 default: return 0;
137 }
138
139 return 0;
140 }
141
sev_fw_alloc(unsigned long len)142 static void *sev_fw_alloc(unsigned long len)
143 {
144 struct page *page;
145
146 page = alloc_pages(GFP_KERNEL, get_order(len));
147 if (!page)
148 return NULL;
149
150 return page_address(page);
151 }
152
__sev_do_cmd_locked(int cmd, void *data, int *psp_ret)153 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
154 {
155 struct psp_device *psp = psp_master;
156 struct sev_device *sev;
157 unsigned int phys_lsb, phys_msb;
158 unsigned int reg, ret = 0;
159 int buf_len;
160
161 if (!psp || !psp->sev_data)
162 return -ENODEV;
163
164 if (psp_dead)
165 return -EBUSY;
166
167 sev = psp->sev_data;
168
169 buf_len = sev_cmd_buffer_len(cmd);
170 if (WARN_ON_ONCE(!data != !buf_len))
171 return -EINVAL;
172
173 /*
174 * Copy the incoming data to driver's scratch buffer as __pa() will not
175 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
176 * physically contiguous.
177 */
178 if (data)
179 memcpy(sev->cmd_buf, data, buf_len);
180
181 /* Get the physical address of the command buffer */
182 phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0;
183 phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0;
184
185 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
186 cmd, phys_msb, phys_lsb, psp_timeout);
187
188 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data,
189 buf_len, false);
190
191 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
192 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
193
194 sev->int_rcvd = 0;
195
196 reg = cmd;
197 reg <<= SEV_CMDRESP_CMD_SHIFT;
198 reg |= SEV_CMDRESP_IOC;
199 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
200
201 /* wait for command completion */
202 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout);
203 if (ret) {
204 if (psp_ret)
205 *psp_ret = 0;
206
207 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
208 psp_dead = true;
209
210 return ret;
211 }
212
213 psp_timeout = psp_cmd_timeout;
214
215 if (psp_ret)
216 *psp_ret = reg & PSP_CMDRESP_ERR_MASK;
217
218 if (reg & PSP_CMDRESP_ERR_MASK) {
219 dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
220 cmd, reg & PSP_CMDRESP_ERR_MASK);
221 ret = -EIO;
222 }
223
224 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
225 buf_len, false);
226
227 /*
228 * Copy potential output from the PSP back to data. Do this even on
229 * failure in case the caller wants to glean something from the error.
230 */
231 if (data)
232 memcpy(data, sev->cmd_buf, buf_len);
233
234 return ret;
235 }
236
sev_do_cmd(int cmd, void *data, int *psp_ret)237 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
238 {
239 int rc;
240
241 mutex_lock(&sev_cmd_mutex);
242 rc = __sev_do_cmd_locked(cmd, data, psp_ret);
243 mutex_unlock(&sev_cmd_mutex);
244
245 return rc;
246 }
247
__sev_platform_init_locked(int *error)248 static int __sev_platform_init_locked(int *error)
249 {
250 struct psp_device *psp = psp_master;
251 struct sev_device *sev;
252 int rc = 0;
253
254 if (!psp || !psp->sev_data)
255 return -ENODEV;
256
257 sev = psp->sev_data;
258
259 if (sev->state == SEV_STATE_INIT)
260 return 0;
261
262 if (sev_es_tmr) {
263 u64 tmr_pa;
264
265 /*
266 * Do not include the encryption mask on the physical
267 * address of the TMR (firmware should clear it anyway).
268 */
269 tmr_pa = __pa(sev_es_tmr);
270
271 sev->init_cmd_buf.flags |= SEV_INIT_FLAGS_SEV_ES;
272 sev->init_cmd_buf.tmr_address = tmr_pa;
273 sev->init_cmd_buf.tmr_len = SEV_ES_TMR_SIZE;
274 }
275
276 rc = __sev_do_cmd_locked(SEV_CMD_INIT, &sev->init_cmd_buf, error);
277 if (rc)
278 return rc;
279
280 sev->state = SEV_STATE_INIT;
281
282 /* Prepare for first SEV guest launch after INIT */
283 wbinvd_on_all_cpus();
284 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
285 if (rc)
286 return rc;
287
288 dev_dbg(sev->dev, "SEV firmware initialized\n");
289
290 return rc;
291 }
292
sev_platform_init(int *error)293 int sev_platform_init(int *error)
294 {
295 int rc;
296
297 mutex_lock(&sev_cmd_mutex);
298 rc = __sev_platform_init_locked(error);
299 mutex_unlock(&sev_cmd_mutex);
300
301 return rc;
302 }
303 EXPORT_SYMBOL_GPL(sev_platform_init);
304
__sev_platform_shutdown_locked(int *error)305 static int __sev_platform_shutdown_locked(int *error)
306 {
307 struct psp_device *psp = psp_master;
308 struct sev_device *sev;
309 int ret;
310
311 if (!psp || !psp->sev_data)
312 return 0;
313
314 sev = psp->sev_data;
315
316 if (sev->state == SEV_STATE_UNINIT)
317 return 0;
318
319 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
320 if (ret)
321 return ret;
322
323 sev->state = SEV_STATE_UNINIT;
324 dev_dbg(sev->dev, "SEV firmware shutdown\n");
325
326 return ret;
327 }
328
sev_platform_shutdown(int *error)329 static int sev_platform_shutdown(int *error)
330 {
331 int rc;
332
333 mutex_lock(&sev_cmd_mutex);
334 rc = __sev_platform_shutdown_locked(NULL);
335 mutex_unlock(&sev_cmd_mutex);
336
337 return rc;
338 }
339
sev_get_platform_state(int *state, int *error)340 static int sev_get_platform_state(int *state, int *error)
341 {
342 struct sev_user_data_status data;
343 int rc;
344
345 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
346 if (rc)
347 return rc;
348
349 *state = data.state;
350 return rc;
351 }
352
sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)353 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
354 {
355 int state, rc;
356
357 if (!writable)
358 return -EPERM;
359
360 /*
361 * The SEV spec requires that FACTORY_RESET must be issued in
362 * UNINIT state. Before we go further lets check if any guest is
363 * active.
364 *
365 * If FW is in WORKING state then deny the request otherwise issue
366 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
367 *
368 */
369 rc = sev_get_platform_state(&state, &argp->error);
370 if (rc)
371 return rc;
372
373 if (state == SEV_STATE_WORKING)
374 return -EBUSY;
375
376 if (state == SEV_STATE_INIT) {
377 rc = __sev_platform_shutdown_locked(&argp->error);
378 if (rc)
379 return rc;
380 }
381
382 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
383 }
384
sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)385 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
386 {
387 struct sev_user_data_status data;
388 int ret;
389
390 memset(&data, 0, sizeof(data));
391
392 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
393 if (ret)
394 return ret;
395
396 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
397 ret = -EFAULT;
398
399 return ret;
400 }
401
sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)402 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
403 {
404 struct sev_device *sev = psp_master->sev_data;
405 int rc;
406
407 if (!writable)
408 return -EPERM;
409
410 if (sev->state == SEV_STATE_UNINIT) {
411 rc = __sev_platform_init_locked(&argp->error);
412 if (rc)
413 return rc;
414 }
415
416 return __sev_do_cmd_locked(cmd, NULL, &argp->error);
417 }
418
sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)419 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
420 {
421 struct sev_device *sev = psp_master->sev_data;
422 struct sev_user_data_pek_csr input;
423 struct sev_data_pek_csr data;
424 void __user *input_address;
425 void *blob = NULL;
426 int ret;
427
428 if (!writable)
429 return -EPERM;
430
431 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
432 return -EFAULT;
433
434 memset(&data, 0, sizeof(data));
435
436 /* userspace wants to query CSR length */
437 if (!input.address || !input.length)
438 goto cmd;
439
440 /* allocate a physically contiguous buffer to store the CSR blob */
441 input_address = (void __user *)input.address;
442 if (input.length > SEV_FW_BLOB_MAX_SIZE)
443 return -EFAULT;
444
445 blob = kzalloc(input.length, GFP_KERNEL);
446 if (!blob)
447 return -ENOMEM;
448
449 data.address = __psp_pa(blob);
450 data.len = input.length;
451
452 cmd:
453 if (sev->state == SEV_STATE_UNINIT) {
454 ret = __sev_platform_init_locked(&argp->error);
455 if (ret)
456 goto e_free_blob;
457 }
458
459 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
460
461 /* If we query the CSR length, FW responded with expected data. */
462 input.length = data.len;
463
464 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
465 ret = -EFAULT;
466 goto e_free_blob;
467 }
468
469 if (blob) {
470 if (copy_to_user(input_address, blob, input.length))
471 ret = -EFAULT;
472 }
473
474 e_free_blob:
475 kfree(blob);
476 return ret;
477 }
478
psp_copy_user_blob(u64 uaddr, u32 len)479 void *psp_copy_user_blob(u64 uaddr, u32 len)
480 {
481 if (!uaddr || !len)
482 return ERR_PTR(-EINVAL);
483
484 /* verify that blob length does not exceed our limit */
485 if (len > SEV_FW_BLOB_MAX_SIZE)
486 return ERR_PTR(-EINVAL);
487
488 return memdup_user((void __user *)uaddr, len);
489 }
490 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
491
sev_get_api_version(void)492 static int sev_get_api_version(void)
493 {
494 struct sev_device *sev = psp_master->sev_data;
495 struct sev_user_data_status status;
496 int error = 0, ret;
497
498 ret = sev_platform_status(&status, &error);
499 if (ret) {
500 dev_err(sev->dev,
501 "SEV: failed to get status. Error: %#x\n", error);
502 return 1;
503 }
504
505 sev->api_major = status.api_major;
506 sev->api_minor = status.api_minor;
507 sev->build = status.build;
508 sev->state = status.state;
509
510 return 0;
511 }
512
sev_get_firmware(struct device *dev, const struct firmware **firmware)513 static int sev_get_firmware(struct device *dev,
514 const struct firmware **firmware)
515 {
516 char fw_name_specific[SEV_FW_NAME_SIZE];
517 char fw_name_subset[SEV_FW_NAME_SIZE];
518
519 snprintf(fw_name_specific, sizeof(fw_name_specific),
520 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
521 boot_cpu_data.x86, boot_cpu_data.x86_model);
522
523 snprintf(fw_name_subset, sizeof(fw_name_subset),
524 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
525 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
526
527 /* Check for SEV FW for a particular model.
528 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
529 *
530 * or
531 *
532 * Check for SEV FW common to a subset of models.
533 * Ex. amd_sev_fam17h_model0xh.sbin for
534 * Family 17h Model 00h -- Family 17h Model 0Fh
535 *
536 * or
537 *
538 * Fall-back to using generic name: sev.fw
539 */
540 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
541 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
542 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
543 return 0;
544
545 return -ENOENT;
546 }
547
548 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device *dev)549 static int sev_update_firmware(struct device *dev)
550 {
551 struct sev_data_download_firmware *data;
552 const struct firmware *firmware;
553 int ret, error, order;
554 struct page *p;
555 u64 data_size;
556
557 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
558 dev_dbg(dev, "No SEV firmware file present\n");
559 return -1;
560 }
561
562 /*
563 * SEV FW expects the physical address given to it to be 32
564 * byte aligned. Memory allocated has structure placed at the
565 * beginning followed by the firmware being passed to the SEV
566 * FW. Allocate enough memory for data structure + alignment
567 * padding + SEV FW.
568 */
569 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
570
571 order = get_order(firmware->size + data_size);
572 p = alloc_pages(GFP_KERNEL, order);
573 if (!p) {
574 ret = -1;
575 goto fw_err;
576 }
577
578 /*
579 * Copy firmware data to a kernel allocated contiguous
580 * memory region.
581 */
582 data = page_address(p);
583 memcpy(page_address(p) + data_size, firmware->data, firmware->size);
584
585 data->address = __psp_pa(page_address(p) + data_size);
586 data->len = firmware->size;
587
588 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
589 if (ret)
590 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
591 else
592 dev_info(dev, "SEV firmware update successful\n");
593
594 __free_pages(p, order);
595
596 fw_err:
597 release_firmware(firmware);
598
599 return ret;
600 }
601
sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)602 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
603 {
604 struct sev_device *sev = psp_master->sev_data;
605 struct sev_user_data_pek_cert_import input;
606 struct sev_data_pek_cert_import data;
607 void *pek_blob, *oca_blob;
608 int ret;
609
610 if (!writable)
611 return -EPERM;
612
613 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
614 return -EFAULT;
615
616 /* copy PEK certificate blobs from userspace */
617 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
618 if (IS_ERR(pek_blob))
619 return PTR_ERR(pek_blob);
620
621 data.reserved = 0;
622 data.pek_cert_address = __psp_pa(pek_blob);
623 data.pek_cert_len = input.pek_cert_len;
624
625 /* copy PEK certificate blobs from userspace */
626 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
627 if (IS_ERR(oca_blob)) {
628 ret = PTR_ERR(oca_blob);
629 goto e_free_pek;
630 }
631
632 data.oca_cert_address = __psp_pa(oca_blob);
633 data.oca_cert_len = input.oca_cert_len;
634
635 /* If platform is not in INIT state then transition it to INIT */
636 if (sev->state != SEV_STATE_INIT) {
637 ret = __sev_platform_init_locked(&argp->error);
638 if (ret)
639 goto e_free_oca;
640 }
641
642 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
643
644 e_free_oca:
645 kfree(oca_blob);
646 e_free_pek:
647 kfree(pek_blob);
648 return ret;
649 }
650
sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)651 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
652 {
653 struct sev_user_data_get_id2 input;
654 struct sev_data_get_id data;
655 void __user *input_address;
656 void *id_blob = NULL;
657 int ret;
658
659 /* SEV GET_ID is available from SEV API v0.16 and up */
660 if (!sev_version_greater_or_equal(0, 16))
661 return -ENOTSUPP;
662
663 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
664 return -EFAULT;
665
666 input_address = (void __user *)input.address;
667
668 if (input.address && input.length) {
669 /*
670 * The length of the ID shouldn't be assumed by software since
671 * it may change in the future. The allocation size is limited
672 * to 1 << (PAGE_SHIFT + MAX_ORDER - 1) by the page allocator.
673 * If the allocation fails, simply return ENOMEM rather than
674 * warning in the kernel log.
675 */
676 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
677 if (!id_blob)
678 return -ENOMEM;
679
680 data.address = __psp_pa(id_blob);
681 data.len = input.length;
682 } else {
683 data.address = 0;
684 data.len = 0;
685 }
686
687 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
688
689 /*
690 * Firmware will return the length of the ID value (either the minimum
691 * required length or the actual length written), return it to the user.
692 */
693 input.length = data.len;
694
695 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
696 ret = -EFAULT;
697 goto e_free;
698 }
699
700 if (id_blob) {
701 if (copy_to_user(input_address, id_blob, data.len)) {
702 ret = -EFAULT;
703 goto e_free;
704 }
705 }
706
707 e_free:
708 kfree(id_blob);
709
710 return ret;
711 }
712
sev_ioctl_do_get_id(struct sev_issue_cmd *argp)713 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
714 {
715 struct sev_data_get_id *data;
716 u64 data_size, user_size;
717 void *id_blob, *mem;
718 int ret;
719
720 /* SEV GET_ID available from SEV API v0.16 and up */
721 if (!sev_version_greater_or_equal(0, 16))
722 return -ENOTSUPP;
723
724 /* SEV FW expects the buffer it fills with the ID to be
725 * 8-byte aligned. Memory allocated should be enough to
726 * hold data structure + alignment padding + memory
727 * where SEV FW writes the ID.
728 */
729 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
730 user_size = sizeof(struct sev_user_data_get_id);
731
732 mem = kzalloc(data_size + user_size, GFP_KERNEL);
733 if (!mem)
734 return -ENOMEM;
735
736 data = mem;
737 id_blob = mem + data_size;
738
739 data->address = __psp_pa(id_blob);
740 data->len = user_size;
741
742 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
743 if (!ret) {
744 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
745 ret = -EFAULT;
746 }
747
748 kfree(mem);
749
750 return ret;
751 }
752
sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)753 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
754 {
755 struct sev_device *sev = psp_master->sev_data;
756 struct sev_user_data_pdh_cert_export input;
757 void *pdh_blob = NULL, *cert_blob = NULL;
758 struct sev_data_pdh_cert_export data;
759 void __user *input_cert_chain_address;
760 void __user *input_pdh_cert_address;
761 int ret;
762
763 /* If platform is not in INIT state then transition it to INIT. */
764 if (sev->state != SEV_STATE_INIT) {
765 if (!writable)
766 return -EPERM;
767
768 ret = __sev_platform_init_locked(&argp->error);
769 if (ret)
770 return ret;
771 }
772
773 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
774 return -EFAULT;
775
776 memset(&data, 0, sizeof(data));
777
778 /* Userspace wants to query the certificate length. */
779 if (!input.pdh_cert_address ||
780 !input.pdh_cert_len ||
781 !input.cert_chain_address)
782 goto cmd;
783
784 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
785 input_cert_chain_address = (void __user *)input.cert_chain_address;
786
787 /* Allocate a physically contiguous buffer to store the PDH blob. */
788 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
789 return -EFAULT;
790
791 /* Allocate a physically contiguous buffer to store the cert chain blob. */
792 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
793 return -EFAULT;
794
795 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
796 if (!pdh_blob)
797 return -ENOMEM;
798
799 data.pdh_cert_address = __psp_pa(pdh_blob);
800 data.pdh_cert_len = input.pdh_cert_len;
801
802 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
803 if (!cert_blob) {
804 ret = -ENOMEM;
805 goto e_free_pdh;
806 }
807
808 data.cert_chain_address = __psp_pa(cert_blob);
809 data.cert_chain_len = input.cert_chain_len;
810
811 cmd:
812 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
813
814 /* If we query the length, FW responded with expected data. */
815 input.cert_chain_len = data.cert_chain_len;
816 input.pdh_cert_len = data.pdh_cert_len;
817
818 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
819 ret = -EFAULT;
820 goto e_free_cert;
821 }
822
823 if (pdh_blob) {
824 if (copy_to_user(input_pdh_cert_address,
825 pdh_blob, input.pdh_cert_len)) {
826 ret = -EFAULT;
827 goto e_free_cert;
828 }
829 }
830
831 if (cert_blob) {
832 if (copy_to_user(input_cert_chain_address,
833 cert_blob, input.cert_chain_len))
834 ret = -EFAULT;
835 }
836
837 e_free_cert:
838 kfree(cert_blob);
839 e_free_pdh:
840 kfree(pdh_blob);
841 return ret;
842 }
843
sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)844 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
845 {
846 void __user *argp = (void __user *)arg;
847 struct sev_issue_cmd input;
848 int ret = -EFAULT;
849 bool writable = file->f_mode & FMODE_WRITE;
850
851 if (!psp_master || !psp_master->sev_data)
852 return -ENODEV;
853
854 if (ioctl != SEV_ISSUE_CMD)
855 return -EINVAL;
856
857 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
858 return -EFAULT;
859
860 if (input.cmd > SEV_MAX)
861 return -EINVAL;
862
863 mutex_lock(&sev_cmd_mutex);
864
865 switch (input.cmd) {
866
867 case SEV_FACTORY_RESET:
868 ret = sev_ioctl_do_reset(&input, writable);
869 break;
870 case SEV_PLATFORM_STATUS:
871 ret = sev_ioctl_do_platform_status(&input);
872 break;
873 case SEV_PEK_GEN:
874 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
875 break;
876 case SEV_PDH_GEN:
877 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
878 break;
879 case SEV_PEK_CSR:
880 ret = sev_ioctl_do_pek_csr(&input, writable);
881 break;
882 case SEV_PEK_CERT_IMPORT:
883 ret = sev_ioctl_do_pek_import(&input, writable);
884 break;
885 case SEV_PDH_CERT_EXPORT:
886 ret = sev_ioctl_do_pdh_export(&input, writable);
887 break;
888 case SEV_GET_ID:
889 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
890 ret = sev_ioctl_do_get_id(&input);
891 break;
892 case SEV_GET_ID2:
893 ret = sev_ioctl_do_get_id2(&input);
894 break;
895 default:
896 ret = -EINVAL;
897 goto out;
898 }
899
900 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
901 ret = -EFAULT;
902 out:
903 mutex_unlock(&sev_cmd_mutex);
904
905 return ret;
906 }
907
908 static const struct file_operations sev_fops = {
909 .owner = THIS_MODULE,
910 .unlocked_ioctl = sev_ioctl,
911 };
912
sev_platform_status(struct sev_user_data_status *data, int *error)913 int sev_platform_status(struct sev_user_data_status *data, int *error)
914 {
915 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
916 }
917 EXPORT_SYMBOL_GPL(sev_platform_status);
918
sev_guest_deactivate(struct sev_data_deactivate *data, int *error)919 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
920 {
921 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
922 }
923 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
924
sev_guest_activate(struct sev_data_activate *data, int *error)925 int sev_guest_activate(struct sev_data_activate *data, int *error)
926 {
927 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
928 }
929 EXPORT_SYMBOL_GPL(sev_guest_activate);
930
sev_guest_decommission(struct sev_data_decommission *data, int *error)931 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
932 {
933 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
934 }
935 EXPORT_SYMBOL_GPL(sev_guest_decommission);
936
sev_guest_df_flush(int *error)937 int sev_guest_df_flush(int *error)
938 {
939 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
940 }
941 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
942
sev_exit(struct kref *ref)943 static void sev_exit(struct kref *ref)
944 {
945 misc_deregister(&misc_dev->misc);
946 kfree(misc_dev);
947 misc_dev = NULL;
948 }
949
sev_misc_init(struct sev_device *sev)950 static int sev_misc_init(struct sev_device *sev)
951 {
952 struct device *dev = sev->dev;
953 int ret;
954
955 /*
956 * SEV feature support can be detected on multiple devices but the SEV
957 * FW commands must be issued on the master. During probe, we do not
958 * know the master hence we create /dev/sev on the first device probe.
959 * sev_do_cmd() finds the right master device to which to issue the
960 * command to the firmware.
961 */
962 if (!misc_dev) {
963 struct miscdevice *misc;
964
965 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
966 if (!misc_dev)
967 return -ENOMEM;
968
969 misc = &misc_dev->misc;
970 misc->minor = MISC_DYNAMIC_MINOR;
971 misc->name = DEVICE_NAME;
972 misc->fops = &sev_fops;
973
974 ret = misc_register(misc);
975 if (ret)
976 return ret;
977
978 kref_init(&misc_dev->refcount);
979 } else {
980 kref_get(&misc_dev->refcount);
981 }
982
983 init_waitqueue_head(&sev->int_queue);
984 sev->misc = misc_dev;
985 dev_dbg(dev, "registered SEV device\n");
986
987 return 0;
988 }
989
sev_dev_init(struct psp_device *psp)990 int sev_dev_init(struct psp_device *psp)
991 {
992 struct device *dev = psp->dev;
993 struct sev_device *sev;
994 int ret = -ENOMEM;
995
996 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
997 if (!sev)
998 goto e_err;
999
1000 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
1001 if (!sev->cmd_buf)
1002 goto e_sev;
1003
1004 psp->sev_data = sev;
1005
1006 sev->dev = dev;
1007 sev->psp = psp;
1008
1009 sev->io_regs = psp->io_regs;
1010
1011 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
1012 if (!sev->vdata) {
1013 ret = -ENODEV;
1014 dev_err(dev, "sev: missing driver data\n");
1015 goto e_buf;
1016 }
1017
1018 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1019
1020 ret = sev_misc_init(sev);
1021 if (ret)
1022 goto e_irq;
1023
1024 dev_notice(dev, "sev enabled\n");
1025
1026 return 0;
1027
1028 e_irq:
1029 psp_clear_sev_irq_handler(psp);
1030 e_buf:
1031 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1032 e_sev:
1033 devm_kfree(dev, sev);
1034 e_err:
1035 psp->sev_data = NULL;
1036
1037 dev_notice(dev, "sev initialization failed\n");
1038
1039 return ret;
1040 }
1041
sev_firmware_shutdown(struct sev_device *sev)1042 static void sev_firmware_shutdown(struct sev_device *sev)
1043 {
1044 sev_platform_shutdown(NULL);
1045
1046 if (sev_es_tmr) {
1047 /* The TMR area was encrypted, flush it from the cache */
1048 wbinvd_on_all_cpus();
1049
1050 free_pages((unsigned long)sev_es_tmr,
1051 get_order(SEV_ES_TMR_SIZE));
1052 sev_es_tmr = NULL;
1053 }
1054 }
1055
sev_dev_destroy(struct psp_device *psp)1056 void sev_dev_destroy(struct psp_device *psp)
1057 {
1058 struct sev_device *sev = psp->sev_data;
1059
1060 if (!sev)
1061 return;
1062
1063 sev_firmware_shutdown(sev);
1064
1065 if (sev->misc)
1066 kref_put(&misc_dev->refcount, sev_exit);
1067
1068 psp_clear_sev_irq_handler(psp);
1069 }
1070
sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, void *data, int *error)1071 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1072 void *data, int *error)
1073 {
1074 if (!filep || filep->f_op != &sev_fops)
1075 return -EBADF;
1076
1077 return sev_do_cmd(cmd, data, error);
1078 }
1079 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1080
sev_pci_init(void)1081 void sev_pci_init(void)
1082 {
1083 struct sev_device *sev = psp_master->sev_data;
1084 int error, rc;
1085
1086 if (!sev)
1087 return;
1088
1089 psp_timeout = psp_probe_timeout;
1090
1091 if (sev_get_api_version())
1092 goto err;
1093
1094 if (sev_version_greater_or_equal(0, 15) &&
1095 sev_update_firmware(sev->dev) == 0)
1096 sev_get_api_version();
1097
1098 /* Obtain the TMR memory area for SEV-ES use */
1099 sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
1100 if (sev_es_tmr)
1101 /* Must flush the cache before giving it to the firmware */
1102 clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE);
1103 else
1104 dev_warn(sev->dev,
1105 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1106
1107 /* Initialize the platform */
1108 rc = sev_platform_init(&error);
1109 if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1110 /*
1111 * INIT command returned an integrity check failure
1112 * status code, meaning that firmware load and
1113 * validation of SEV related persistent data has
1114 * failed and persistent state has been erased.
1115 * Retrying INIT command here should succeed.
1116 */
1117 dev_dbg(sev->dev, "SEV: retrying INIT command");
1118 rc = sev_platform_init(&error);
1119 }
1120
1121 if (rc) {
1122 dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1123 return;
1124 }
1125
1126 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1127 sev->api_minor, sev->build);
1128
1129 return;
1130
1131 err:
1132 psp_master->sev_data = NULL;
1133 }
1134
sev_pci_exit(void)1135 void sev_pci_exit(void)
1136 {
1137 struct sev_device *sev = psp_master->sev_data;
1138
1139 if (!sev)
1140 return;
1141
1142 sev_firmware_shutdown(sev);
1143 }
1144