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