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 sev_device *sev = psp_master->sev_data;
308 int ret;
309
310 if (!sev || sev->state == SEV_STATE_UNINIT)
311 return 0;
312
313 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
314 if (ret)
315 return ret;
316
317 sev->state = SEV_STATE_UNINIT;
318 dev_dbg(sev->dev, "SEV firmware shutdown\n");
319
320 return ret;
321 }
322
sev_platform_shutdown(int * error)323 static int sev_platform_shutdown(int *error)
324 {
325 int rc;
326
327 mutex_lock(&sev_cmd_mutex);
328 rc = __sev_platform_shutdown_locked(NULL);
329 mutex_unlock(&sev_cmd_mutex);
330
331 return rc;
332 }
333
sev_get_platform_state(int * state,int * error)334 static int sev_get_platform_state(int *state, int *error)
335 {
336 struct sev_user_data_status data;
337 int rc;
338
339 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
340 if (rc)
341 return rc;
342
343 *state = data.state;
344 return rc;
345 }
346
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)347 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
348 {
349 int state, rc;
350
351 if (!writable)
352 return -EPERM;
353
354 /*
355 * The SEV spec requires that FACTORY_RESET must be issued in
356 * UNINIT state. Before we go further lets check if any guest is
357 * active.
358 *
359 * If FW is in WORKING state then deny the request otherwise issue
360 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
361 *
362 */
363 rc = sev_get_platform_state(&state, &argp->error);
364 if (rc)
365 return rc;
366
367 if (state == SEV_STATE_WORKING)
368 return -EBUSY;
369
370 if (state == SEV_STATE_INIT) {
371 rc = __sev_platform_shutdown_locked(&argp->error);
372 if (rc)
373 return rc;
374 }
375
376 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
377 }
378
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)379 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
380 {
381 struct sev_user_data_status data;
382 int ret;
383
384 memset(&data, 0, sizeof(data));
385
386 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
387 if (ret)
388 return ret;
389
390 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
391 ret = -EFAULT;
392
393 return ret;
394 }
395
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)396 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
397 {
398 struct sev_device *sev = psp_master->sev_data;
399 int rc;
400
401 if (!writable)
402 return -EPERM;
403
404 if (sev->state == SEV_STATE_UNINIT) {
405 rc = __sev_platform_init_locked(&argp->error);
406 if (rc)
407 return rc;
408 }
409
410 return __sev_do_cmd_locked(cmd, NULL, &argp->error);
411 }
412
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)413 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
414 {
415 struct sev_device *sev = psp_master->sev_data;
416 struct sev_user_data_pek_csr input;
417 struct sev_data_pek_csr data;
418 void __user *input_address;
419 void *blob = NULL;
420 int ret;
421
422 if (!writable)
423 return -EPERM;
424
425 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
426 return -EFAULT;
427
428 memset(&data, 0, sizeof(data));
429
430 /* userspace wants to query CSR length */
431 if (!input.address || !input.length)
432 goto cmd;
433
434 /* allocate a physically contiguous buffer to store the CSR blob */
435 input_address = (void __user *)input.address;
436 if (input.length > SEV_FW_BLOB_MAX_SIZE)
437 return -EFAULT;
438
439 blob = kzalloc(input.length, GFP_KERNEL);
440 if (!blob)
441 return -ENOMEM;
442
443 data.address = __psp_pa(blob);
444 data.len = input.length;
445
446 cmd:
447 if (sev->state == SEV_STATE_UNINIT) {
448 ret = __sev_platform_init_locked(&argp->error);
449 if (ret)
450 goto e_free_blob;
451 }
452
453 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
454
455 /* If we query the CSR length, FW responded with expected data. */
456 input.length = data.len;
457
458 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
459 ret = -EFAULT;
460 goto e_free_blob;
461 }
462
463 if (blob) {
464 if (copy_to_user(input_address, blob, input.length))
465 ret = -EFAULT;
466 }
467
468 e_free_blob:
469 kfree(blob);
470 return ret;
471 }
472
psp_copy_user_blob(u64 uaddr,u32 len)473 void *psp_copy_user_blob(u64 uaddr, u32 len)
474 {
475 if (!uaddr || !len)
476 return ERR_PTR(-EINVAL);
477
478 /* verify that blob length does not exceed our limit */
479 if (len > SEV_FW_BLOB_MAX_SIZE)
480 return ERR_PTR(-EINVAL);
481
482 return memdup_user((void __user *)uaddr, len);
483 }
484 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
485
sev_get_api_version(void)486 static int sev_get_api_version(void)
487 {
488 struct sev_device *sev = psp_master->sev_data;
489 struct sev_user_data_status status;
490 int error = 0, ret;
491
492 ret = sev_platform_status(&status, &error);
493 if (ret) {
494 dev_err(sev->dev,
495 "SEV: failed to get status. Error: %#x\n", error);
496 return 1;
497 }
498
499 sev->api_major = status.api_major;
500 sev->api_minor = status.api_minor;
501 sev->build = status.build;
502 sev->state = status.state;
503
504 return 0;
505 }
506
sev_get_firmware(struct device * dev,const struct firmware ** firmware)507 static int sev_get_firmware(struct device *dev,
508 const struct firmware **firmware)
509 {
510 char fw_name_specific[SEV_FW_NAME_SIZE];
511 char fw_name_subset[SEV_FW_NAME_SIZE];
512
513 snprintf(fw_name_specific, sizeof(fw_name_specific),
514 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
515 boot_cpu_data.x86, boot_cpu_data.x86_model);
516
517 snprintf(fw_name_subset, sizeof(fw_name_subset),
518 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
519 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
520
521 /* Check for SEV FW for a particular model.
522 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
523 *
524 * or
525 *
526 * Check for SEV FW common to a subset of models.
527 * Ex. amd_sev_fam17h_model0xh.sbin for
528 * Family 17h Model 00h -- Family 17h Model 0Fh
529 *
530 * or
531 *
532 * Fall-back to using generic name: sev.fw
533 */
534 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
535 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
536 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
537 return 0;
538
539 return -ENOENT;
540 }
541
542 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)543 static int sev_update_firmware(struct device *dev)
544 {
545 struct sev_data_download_firmware *data;
546 const struct firmware *firmware;
547 int ret, error, order;
548 struct page *p;
549 u64 data_size;
550
551 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
552 dev_dbg(dev, "No SEV firmware file present\n");
553 return -1;
554 }
555
556 /*
557 * SEV FW expects the physical address given to it to be 32
558 * byte aligned. Memory allocated has structure placed at the
559 * beginning followed by the firmware being passed to the SEV
560 * FW. Allocate enough memory for data structure + alignment
561 * padding + SEV FW.
562 */
563 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
564
565 order = get_order(firmware->size + data_size);
566 p = alloc_pages(GFP_KERNEL, order);
567 if (!p) {
568 ret = -1;
569 goto fw_err;
570 }
571
572 /*
573 * Copy firmware data to a kernel allocated contiguous
574 * memory region.
575 */
576 data = page_address(p);
577 memcpy(page_address(p) + data_size, firmware->data, firmware->size);
578
579 data->address = __psp_pa(page_address(p) + data_size);
580 data->len = firmware->size;
581
582 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
583 if (ret)
584 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
585 else
586 dev_info(dev, "SEV firmware update successful\n");
587
588 __free_pages(p, order);
589
590 fw_err:
591 release_firmware(firmware);
592
593 return ret;
594 }
595
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)596 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
597 {
598 struct sev_device *sev = psp_master->sev_data;
599 struct sev_user_data_pek_cert_import input;
600 struct sev_data_pek_cert_import data;
601 void *pek_blob, *oca_blob;
602 int ret;
603
604 if (!writable)
605 return -EPERM;
606
607 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
608 return -EFAULT;
609
610 /* copy PEK certificate blobs from userspace */
611 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
612 if (IS_ERR(pek_blob))
613 return PTR_ERR(pek_blob);
614
615 data.reserved = 0;
616 data.pek_cert_address = __psp_pa(pek_blob);
617 data.pek_cert_len = input.pek_cert_len;
618
619 /* copy PEK certificate blobs from userspace */
620 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
621 if (IS_ERR(oca_blob)) {
622 ret = PTR_ERR(oca_blob);
623 goto e_free_pek;
624 }
625
626 data.oca_cert_address = __psp_pa(oca_blob);
627 data.oca_cert_len = input.oca_cert_len;
628
629 /* If platform is not in INIT state then transition it to INIT */
630 if (sev->state != SEV_STATE_INIT) {
631 ret = __sev_platform_init_locked(&argp->error);
632 if (ret)
633 goto e_free_oca;
634 }
635
636 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
637
638 e_free_oca:
639 kfree(oca_blob);
640 e_free_pek:
641 kfree(pek_blob);
642 return ret;
643 }
644
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)645 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
646 {
647 struct sev_user_data_get_id2 input;
648 struct sev_data_get_id data;
649 void __user *input_address;
650 void *id_blob = NULL;
651 int ret;
652
653 /* SEV GET_ID is available from SEV API v0.16 and up */
654 if (!sev_version_greater_or_equal(0, 16))
655 return -ENOTSUPP;
656
657 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
658 return -EFAULT;
659
660 input_address = (void __user *)input.address;
661
662 if (input.address && input.length) {
663 /*
664 * The length of the ID shouldn't be assumed by software since
665 * it may change in the future. The allocation size is limited
666 * to 1 << (PAGE_SHIFT + MAX_ORDER - 1) by the page allocator.
667 * If the allocation fails, simply return ENOMEM rather than
668 * warning in the kernel log.
669 */
670 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN);
671 if (!id_blob)
672 return -ENOMEM;
673
674 data.address = __psp_pa(id_blob);
675 data.len = input.length;
676 } else {
677 data.address = 0;
678 data.len = 0;
679 }
680
681 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
682
683 /*
684 * Firmware will return the length of the ID value (either the minimum
685 * required length or the actual length written), return it to the user.
686 */
687 input.length = data.len;
688
689 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
690 ret = -EFAULT;
691 goto e_free;
692 }
693
694 if (id_blob) {
695 if (copy_to_user(input_address, id_blob, data.len)) {
696 ret = -EFAULT;
697 goto e_free;
698 }
699 }
700
701 e_free:
702 kfree(id_blob);
703
704 return ret;
705 }
706
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)707 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
708 {
709 struct sev_data_get_id *data;
710 u64 data_size, user_size;
711 void *id_blob, *mem;
712 int ret;
713
714 /* SEV GET_ID available from SEV API v0.16 and up */
715 if (!sev_version_greater_or_equal(0, 16))
716 return -ENOTSUPP;
717
718 /* SEV FW expects the buffer it fills with the ID to be
719 * 8-byte aligned. Memory allocated should be enough to
720 * hold data structure + alignment padding + memory
721 * where SEV FW writes the ID.
722 */
723 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
724 user_size = sizeof(struct sev_user_data_get_id);
725
726 mem = kzalloc(data_size + user_size, GFP_KERNEL);
727 if (!mem)
728 return -ENOMEM;
729
730 data = mem;
731 id_blob = mem + data_size;
732
733 data->address = __psp_pa(id_blob);
734 data->len = user_size;
735
736 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
737 if (!ret) {
738 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
739 ret = -EFAULT;
740 }
741
742 kfree(mem);
743
744 return ret;
745 }
746
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)747 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
748 {
749 struct sev_device *sev = psp_master->sev_data;
750 struct sev_user_data_pdh_cert_export input;
751 void *pdh_blob = NULL, *cert_blob = NULL;
752 struct sev_data_pdh_cert_export data;
753 void __user *input_cert_chain_address;
754 void __user *input_pdh_cert_address;
755 int ret;
756
757 /* If platform is not in INIT state then transition it to INIT. */
758 if (sev->state != SEV_STATE_INIT) {
759 if (!writable)
760 return -EPERM;
761
762 ret = __sev_platform_init_locked(&argp->error);
763 if (ret)
764 return ret;
765 }
766
767 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
768 return -EFAULT;
769
770 memset(&data, 0, sizeof(data));
771
772 /* Userspace wants to query the certificate length. */
773 if (!input.pdh_cert_address ||
774 !input.pdh_cert_len ||
775 !input.cert_chain_address)
776 goto cmd;
777
778 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
779 input_cert_chain_address = (void __user *)input.cert_chain_address;
780
781 /* Allocate a physically contiguous buffer to store the PDH blob. */
782 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
783 return -EFAULT;
784
785 /* Allocate a physically contiguous buffer to store the cert chain blob. */
786 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
787 return -EFAULT;
788
789 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL);
790 if (!pdh_blob)
791 return -ENOMEM;
792
793 data.pdh_cert_address = __psp_pa(pdh_blob);
794 data.pdh_cert_len = input.pdh_cert_len;
795
796 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL);
797 if (!cert_blob) {
798 ret = -ENOMEM;
799 goto e_free_pdh;
800 }
801
802 data.cert_chain_address = __psp_pa(cert_blob);
803 data.cert_chain_len = input.cert_chain_len;
804
805 cmd:
806 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
807
808 /* If we query the length, FW responded with expected data. */
809 input.cert_chain_len = data.cert_chain_len;
810 input.pdh_cert_len = data.pdh_cert_len;
811
812 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
813 ret = -EFAULT;
814 goto e_free_cert;
815 }
816
817 if (pdh_blob) {
818 if (copy_to_user(input_pdh_cert_address,
819 pdh_blob, input.pdh_cert_len)) {
820 ret = -EFAULT;
821 goto e_free_cert;
822 }
823 }
824
825 if (cert_blob) {
826 if (copy_to_user(input_cert_chain_address,
827 cert_blob, input.cert_chain_len))
828 ret = -EFAULT;
829 }
830
831 e_free_cert:
832 kfree(cert_blob);
833 e_free_pdh:
834 kfree(pdh_blob);
835 return ret;
836 }
837
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)838 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
839 {
840 void __user *argp = (void __user *)arg;
841 struct sev_issue_cmd input;
842 int ret = -EFAULT;
843 bool writable = file->f_mode & FMODE_WRITE;
844
845 if (!psp_master || !psp_master->sev_data)
846 return -ENODEV;
847
848 if (ioctl != SEV_ISSUE_CMD)
849 return -EINVAL;
850
851 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
852 return -EFAULT;
853
854 if (input.cmd > SEV_MAX)
855 return -EINVAL;
856
857 mutex_lock(&sev_cmd_mutex);
858
859 switch (input.cmd) {
860
861 case SEV_FACTORY_RESET:
862 ret = sev_ioctl_do_reset(&input, writable);
863 break;
864 case SEV_PLATFORM_STATUS:
865 ret = sev_ioctl_do_platform_status(&input);
866 break;
867 case SEV_PEK_GEN:
868 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
869 break;
870 case SEV_PDH_GEN:
871 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
872 break;
873 case SEV_PEK_CSR:
874 ret = sev_ioctl_do_pek_csr(&input, writable);
875 break;
876 case SEV_PEK_CERT_IMPORT:
877 ret = sev_ioctl_do_pek_import(&input, writable);
878 break;
879 case SEV_PDH_CERT_EXPORT:
880 ret = sev_ioctl_do_pdh_export(&input, writable);
881 break;
882 case SEV_GET_ID:
883 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
884 ret = sev_ioctl_do_get_id(&input);
885 break;
886 case SEV_GET_ID2:
887 ret = sev_ioctl_do_get_id2(&input);
888 break;
889 default:
890 ret = -EINVAL;
891 goto out;
892 }
893
894 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
895 ret = -EFAULT;
896 out:
897 mutex_unlock(&sev_cmd_mutex);
898
899 return ret;
900 }
901
902 static const struct file_operations sev_fops = {
903 .owner = THIS_MODULE,
904 .unlocked_ioctl = sev_ioctl,
905 };
906
sev_platform_status(struct sev_user_data_status * data,int * error)907 int sev_platform_status(struct sev_user_data_status *data, int *error)
908 {
909 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
910 }
911 EXPORT_SYMBOL_GPL(sev_platform_status);
912
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)913 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
914 {
915 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
916 }
917 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
918
sev_guest_activate(struct sev_data_activate * data,int * error)919 int sev_guest_activate(struct sev_data_activate *data, int *error)
920 {
921 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
922 }
923 EXPORT_SYMBOL_GPL(sev_guest_activate);
924
sev_guest_decommission(struct sev_data_decommission * data,int * error)925 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
926 {
927 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
928 }
929 EXPORT_SYMBOL_GPL(sev_guest_decommission);
930
sev_guest_df_flush(int * error)931 int sev_guest_df_flush(int *error)
932 {
933 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
934 }
935 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
936
sev_exit(struct kref * ref)937 static void sev_exit(struct kref *ref)
938 {
939 misc_deregister(&misc_dev->misc);
940 kfree(misc_dev);
941 misc_dev = NULL;
942 }
943
sev_misc_init(struct sev_device * sev)944 static int sev_misc_init(struct sev_device *sev)
945 {
946 struct device *dev = sev->dev;
947 int ret;
948
949 /*
950 * SEV feature support can be detected on multiple devices but the SEV
951 * FW commands must be issued on the master. During probe, we do not
952 * know the master hence we create /dev/sev on the first device probe.
953 * sev_do_cmd() finds the right master device to which to issue the
954 * command to the firmware.
955 */
956 if (!misc_dev) {
957 struct miscdevice *misc;
958
959 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
960 if (!misc_dev)
961 return -ENOMEM;
962
963 misc = &misc_dev->misc;
964 misc->minor = MISC_DYNAMIC_MINOR;
965 misc->name = DEVICE_NAME;
966 misc->fops = &sev_fops;
967
968 ret = misc_register(misc);
969 if (ret)
970 return ret;
971
972 kref_init(&misc_dev->refcount);
973 } else {
974 kref_get(&misc_dev->refcount);
975 }
976
977 init_waitqueue_head(&sev->int_queue);
978 sev->misc = misc_dev;
979 dev_dbg(dev, "registered SEV device\n");
980
981 return 0;
982 }
983
sev_dev_init(struct psp_device * psp)984 int sev_dev_init(struct psp_device *psp)
985 {
986 struct device *dev = psp->dev;
987 struct sev_device *sev;
988 int ret = -ENOMEM;
989
990 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
991 if (!sev)
992 goto e_err;
993
994 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
995 if (!sev->cmd_buf)
996 goto e_sev;
997
998 psp->sev_data = sev;
999
1000 sev->dev = dev;
1001 sev->psp = psp;
1002
1003 sev->io_regs = psp->io_regs;
1004
1005 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
1006 if (!sev->vdata) {
1007 ret = -ENODEV;
1008 dev_err(dev, "sev: missing driver data\n");
1009 goto e_buf;
1010 }
1011
1012 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1013
1014 ret = sev_misc_init(sev);
1015 if (ret)
1016 goto e_irq;
1017
1018 dev_notice(dev, "sev enabled\n");
1019
1020 return 0;
1021
1022 e_irq:
1023 psp_clear_sev_irq_handler(psp);
1024 e_buf:
1025 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1026 e_sev:
1027 devm_kfree(dev, sev);
1028 e_err:
1029 psp->sev_data = NULL;
1030
1031 dev_notice(dev, "sev initialization failed\n");
1032
1033 return ret;
1034 }
1035
sev_firmware_shutdown(struct sev_device * sev)1036 static void sev_firmware_shutdown(struct sev_device *sev)
1037 {
1038 sev_platform_shutdown(NULL);
1039
1040 if (sev_es_tmr) {
1041 /* The TMR area was encrypted, flush it from the cache */
1042 wbinvd_on_all_cpus();
1043
1044 free_pages((unsigned long)sev_es_tmr,
1045 get_order(SEV_ES_TMR_SIZE));
1046 sev_es_tmr = NULL;
1047 }
1048 }
1049
sev_dev_destroy(struct psp_device * psp)1050 void sev_dev_destroy(struct psp_device *psp)
1051 {
1052 struct sev_device *sev = psp->sev_data;
1053
1054 if (!sev)
1055 return;
1056
1057 sev_firmware_shutdown(sev);
1058
1059 if (sev->misc)
1060 kref_put(&misc_dev->refcount, sev_exit);
1061
1062 psp_clear_sev_irq_handler(psp);
1063 }
1064
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)1065 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1066 void *data, int *error)
1067 {
1068 if (!filep || filep->f_op != &sev_fops)
1069 return -EBADF;
1070
1071 return sev_do_cmd(cmd, data, error);
1072 }
1073 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1074
sev_pci_init(void)1075 void sev_pci_init(void)
1076 {
1077 struct sev_device *sev = psp_master->sev_data;
1078 int error, rc;
1079
1080 if (!sev)
1081 return;
1082
1083 psp_timeout = psp_probe_timeout;
1084
1085 if (sev_get_api_version())
1086 goto err;
1087
1088 if (sev_version_greater_or_equal(0, 15) &&
1089 sev_update_firmware(sev->dev) == 0)
1090 sev_get_api_version();
1091
1092 /* Obtain the TMR memory area for SEV-ES use */
1093 sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE);
1094 if (sev_es_tmr)
1095 /* Must flush the cache before giving it to the firmware */
1096 clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE);
1097 else
1098 dev_warn(sev->dev,
1099 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1100
1101 /* Initialize the platform */
1102 rc = sev_platform_init(&error);
1103 if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1104 /*
1105 * INIT command returned an integrity check failure
1106 * status code, meaning that firmware load and
1107 * validation of SEV related persistent data has
1108 * failed and persistent state has been erased.
1109 * Retrying INIT command here should succeed.
1110 */
1111 dev_dbg(sev->dev, "SEV: retrying INIT command");
1112 rc = sev_platform_init(&error);
1113 }
1114
1115 if (rc) {
1116 dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1117 return;
1118 }
1119
1120 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1121 sev->api_minor, sev->build);
1122
1123 return;
1124
1125 err:
1126 psp_master->sev_data = NULL;
1127 }
1128
sev_pci_exit(void)1129 void sev_pci_exit(void)
1130 {
1131 struct sev_device *sev = psp_master->sev_data;
1132
1133 if (!sev)
1134 return;
1135
1136 sev_firmware_shutdown(sev);
1137 }
1138