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 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 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report);
137 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel);
138 default: return 0;
139 }
140
141 return 0;
142 }
143
__sev_do_cmd_locked(int cmd,void * data,int * psp_ret)144 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret)
145 {
146 struct psp_device *psp = psp_master;
147 struct sev_device *sev;
148 unsigned int phys_lsb, phys_msb;
149 unsigned int reg, ret = 0;
150 int buf_len;
151
152 if (!psp || !psp->sev_data)
153 return -ENODEV;
154
155 if (psp_dead)
156 return -EBUSY;
157
158 sev = psp->sev_data;
159
160 buf_len = sev_cmd_buffer_len(cmd);
161 if (WARN_ON_ONCE(!data != !buf_len))
162 return -EINVAL;
163
164 /*
165 * Copy the incoming data to driver's scratch buffer as __pa() will not
166 * work for some memory, e.g. vmalloc'd addresses, and @data may not be
167 * physically contiguous.
168 */
169 if (data)
170 memcpy(sev->cmd_buf, data, buf_len);
171
172 /* Get the physical address of the command buffer */
173 phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0;
174 phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0;
175
176 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n",
177 cmd, phys_msb, phys_lsb, psp_timeout);
178
179 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data,
180 buf_len, false);
181
182 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg);
183 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg);
184
185 sev->int_rcvd = 0;
186
187 reg = cmd;
188 reg <<= SEV_CMDRESP_CMD_SHIFT;
189 reg |= SEV_CMDRESP_IOC;
190 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg);
191
192 /* wait for command completion */
193 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout);
194 if (ret) {
195 if (psp_ret)
196 *psp_ret = 0;
197
198 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd);
199 psp_dead = true;
200
201 return ret;
202 }
203
204 psp_timeout = psp_cmd_timeout;
205
206 if (psp_ret)
207 *psp_ret = reg & PSP_CMDRESP_ERR_MASK;
208
209 if (reg & PSP_CMDRESP_ERR_MASK) {
210 dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n",
211 cmd, reg & PSP_CMDRESP_ERR_MASK);
212 ret = -EIO;
213 }
214
215 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data,
216 buf_len, false);
217
218 /*
219 * Copy potential output from the PSP back to data. Do this even on
220 * failure in case the caller wants to glean something from the error.
221 */
222 if (data)
223 memcpy(data, sev->cmd_buf, buf_len);
224
225 return ret;
226 }
227
sev_do_cmd(int cmd,void * data,int * psp_ret)228 static int sev_do_cmd(int cmd, void *data, int *psp_ret)
229 {
230 int rc;
231
232 mutex_lock(&sev_cmd_mutex);
233 rc = __sev_do_cmd_locked(cmd, data, psp_ret);
234 mutex_unlock(&sev_cmd_mutex);
235
236 return rc;
237 }
238
__sev_platform_init_locked(int * error)239 static int __sev_platform_init_locked(int *error)
240 {
241 struct psp_device *psp = psp_master;
242 struct sev_data_init data;
243 struct sev_device *sev;
244 int rc = 0;
245
246 if (!psp || !psp->sev_data)
247 return -ENODEV;
248
249 sev = psp->sev_data;
250
251 if (sev->state == SEV_STATE_INIT)
252 return 0;
253
254 memset(&data, 0, sizeof(data));
255 if (sev_es_tmr) {
256 u64 tmr_pa;
257
258 /*
259 * Do not include the encryption mask on the physical
260 * address of the TMR (firmware should clear it anyway).
261 */
262 tmr_pa = __pa(sev_es_tmr);
263
264 data.flags |= SEV_INIT_FLAGS_SEV_ES;
265 data.tmr_address = tmr_pa;
266 data.tmr_len = SEV_ES_TMR_SIZE;
267 }
268
269 rc = __sev_do_cmd_locked(SEV_CMD_INIT, &data, error);
270 if (rc)
271 return rc;
272
273 sev->state = SEV_STATE_INIT;
274
275 /* Prepare for first SEV guest launch after INIT */
276 wbinvd_on_all_cpus();
277 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error);
278 if (rc)
279 return rc;
280
281 dev_dbg(sev->dev, "SEV firmware initialized\n");
282
283 return rc;
284 }
285
sev_platform_init(int * error)286 int sev_platform_init(int *error)
287 {
288 int rc;
289
290 mutex_lock(&sev_cmd_mutex);
291 rc = __sev_platform_init_locked(error);
292 mutex_unlock(&sev_cmd_mutex);
293
294 return rc;
295 }
296 EXPORT_SYMBOL_GPL(sev_platform_init);
297
__sev_platform_shutdown_locked(int * error)298 static int __sev_platform_shutdown_locked(int *error)
299 {
300 struct sev_device *sev = psp_master->sev_data;
301 int ret;
302
303 if (sev->state == SEV_STATE_UNINIT)
304 return 0;
305
306 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error);
307 if (ret)
308 return ret;
309
310 sev->state = SEV_STATE_UNINIT;
311 dev_dbg(sev->dev, "SEV firmware shutdown\n");
312
313 return ret;
314 }
315
sev_platform_shutdown(int * error)316 static int sev_platform_shutdown(int *error)
317 {
318 int rc;
319
320 mutex_lock(&sev_cmd_mutex);
321 rc = __sev_platform_shutdown_locked(NULL);
322 mutex_unlock(&sev_cmd_mutex);
323
324 return rc;
325 }
326
sev_get_platform_state(int * state,int * error)327 static int sev_get_platform_state(int *state, int *error)
328 {
329 struct sev_user_data_status data;
330 int rc;
331
332 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error);
333 if (rc)
334 return rc;
335
336 *state = data.state;
337 return rc;
338 }
339
sev_ioctl_do_reset(struct sev_issue_cmd * argp,bool writable)340 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable)
341 {
342 int state, rc;
343
344 if (!writable)
345 return -EPERM;
346
347 /*
348 * The SEV spec requires that FACTORY_RESET must be issued in
349 * UNINIT state. Before we go further lets check if any guest is
350 * active.
351 *
352 * If FW is in WORKING state then deny the request otherwise issue
353 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.
354 *
355 */
356 rc = sev_get_platform_state(&state, &argp->error);
357 if (rc)
358 return rc;
359
360 if (state == SEV_STATE_WORKING)
361 return -EBUSY;
362
363 if (state == SEV_STATE_INIT) {
364 rc = __sev_platform_shutdown_locked(&argp->error);
365 if (rc)
366 return rc;
367 }
368
369 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error);
370 }
371
sev_ioctl_do_platform_status(struct sev_issue_cmd * argp)372 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp)
373 {
374 struct sev_user_data_status data;
375 int ret;
376
377 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error);
378 if (ret)
379 return ret;
380
381 if (copy_to_user((void __user *)argp->data, &data, sizeof(data)))
382 ret = -EFAULT;
383
384 return ret;
385 }
386
sev_ioctl_do_pek_pdh_gen(int cmd,struct sev_issue_cmd * argp,bool writable)387 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable)
388 {
389 struct sev_device *sev = psp_master->sev_data;
390 int rc;
391
392 if (!writable)
393 return -EPERM;
394
395 if (sev->state == SEV_STATE_UNINIT) {
396 rc = __sev_platform_init_locked(&argp->error);
397 if (rc)
398 return rc;
399 }
400
401 return __sev_do_cmd_locked(cmd, NULL, &argp->error);
402 }
403
sev_ioctl_do_pek_csr(struct sev_issue_cmd * argp,bool writable)404 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable)
405 {
406 struct sev_device *sev = psp_master->sev_data;
407 struct sev_user_data_pek_csr input;
408 struct sev_data_pek_csr data;
409 void __user *input_address;
410 void *blob = NULL;
411 int ret;
412
413 if (!writable)
414 return -EPERM;
415
416 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
417 return -EFAULT;
418
419 memset(&data, 0, sizeof(data));
420
421 /* userspace wants to query CSR length */
422 if (!input.address || !input.length)
423 goto cmd;
424
425 /* allocate a physically contiguous buffer to store the CSR blob */
426 input_address = (void __user *)input.address;
427 if (input.length > SEV_FW_BLOB_MAX_SIZE)
428 return -EFAULT;
429
430 blob = kmalloc(input.length, GFP_KERNEL);
431 if (!blob)
432 return -ENOMEM;
433
434 data.address = __psp_pa(blob);
435 data.len = input.length;
436
437 cmd:
438 if (sev->state == SEV_STATE_UNINIT) {
439 ret = __sev_platform_init_locked(&argp->error);
440 if (ret)
441 goto e_free_blob;
442 }
443
444 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error);
445
446 /* If we query the CSR length, FW responded with expected data. */
447 input.length = data.len;
448
449 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
450 ret = -EFAULT;
451 goto e_free_blob;
452 }
453
454 if (blob) {
455 if (copy_to_user(input_address, blob, input.length))
456 ret = -EFAULT;
457 }
458
459 e_free_blob:
460 kfree(blob);
461 return ret;
462 }
463
psp_copy_user_blob(u64 uaddr,u32 len)464 void *psp_copy_user_blob(u64 uaddr, u32 len)
465 {
466 if (!uaddr || !len)
467 return ERR_PTR(-EINVAL);
468
469 /* verify that blob length does not exceed our limit */
470 if (len > SEV_FW_BLOB_MAX_SIZE)
471 return ERR_PTR(-EINVAL);
472
473 return memdup_user((void __user *)uaddr, len);
474 }
475 EXPORT_SYMBOL_GPL(psp_copy_user_blob);
476
sev_get_api_version(void)477 static int sev_get_api_version(void)
478 {
479 struct sev_device *sev = psp_master->sev_data;
480 struct sev_user_data_status status;
481 int error = 0, ret;
482
483 ret = sev_platform_status(&status, &error);
484 if (ret) {
485 dev_err(sev->dev,
486 "SEV: failed to get status. Error: %#x\n", error);
487 return 1;
488 }
489
490 sev->api_major = status.api_major;
491 sev->api_minor = status.api_minor;
492 sev->build = status.build;
493 sev->state = status.state;
494
495 return 0;
496 }
497
sev_get_firmware(struct device * dev,const struct firmware ** firmware)498 static int sev_get_firmware(struct device *dev,
499 const struct firmware **firmware)
500 {
501 char fw_name_specific[SEV_FW_NAME_SIZE];
502 char fw_name_subset[SEV_FW_NAME_SIZE];
503
504 snprintf(fw_name_specific, sizeof(fw_name_specific),
505 "amd/amd_sev_fam%.2xh_model%.2xh.sbin",
506 boot_cpu_data.x86, boot_cpu_data.x86_model);
507
508 snprintf(fw_name_subset, sizeof(fw_name_subset),
509 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin",
510 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4);
511
512 /* Check for SEV FW for a particular model.
513 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h
514 *
515 * or
516 *
517 * Check for SEV FW common to a subset of models.
518 * Ex. amd_sev_fam17h_model0xh.sbin for
519 * Family 17h Model 00h -- Family 17h Model 0Fh
520 *
521 * or
522 *
523 * Fall-back to using generic name: sev.fw
524 */
525 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) ||
526 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) ||
527 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0))
528 return 0;
529
530 return -ENOENT;
531 }
532
533 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */
sev_update_firmware(struct device * dev)534 static int sev_update_firmware(struct device *dev)
535 {
536 struct sev_data_download_firmware *data;
537 const struct firmware *firmware;
538 int ret, error, order;
539 struct page *p;
540 u64 data_size;
541
542 if (sev_get_firmware(dev, &firmware) == -ENOENT) {
543 dev_dbg(dev, "No SEV firmware file present\n");
544 return -1;
545 }
546
547 /*
548 * SEV FW expects the physical address given to it to be 32
549 * byte aligned. Memory allocated has structure placed at the
550 * beginning followed by the firmware being passed to the SEV
551 * FW. Allocate enough memory for data structure + alignment
552 * padding + SEV FW.
553 */
554 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32);
555
556 order = get_order(firmware->size + data_size);
557 p = alloc_pages(GFP_KERNEL, order);
558 if (!p) {
559 ret = -1;
560 goto fw_err;
561 }
562
563 /*
564 * Copy firmware data to a kernel allocated contiguous
565 * memory region.
566 */
567 data = page_address(p);
568 memcpy(page_address(p) + data_size, firmware->data, firmware->size);
569
570 data->address = __psp_pa(page_address(p) + data_size);
571 data->len = firmware->size;
572
573 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error);
574 if (ret)
575 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error);
576 else
577 dev_info(dev, "SEV firmware update successful\n");
578
579 __free_pages(p, order);
580
581 fw_err:
582 release_firmware(firmware);
583
584 return ret;
585 }
586
sev_ioctl_do_pek_import(struct sev_issue_cmd * argp,bool writable)587 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable)
588 {
589 struct sev_device *sev = psp_master->sev_data;
590 struct sev_user_data_pek_cert_import input;
591 struct sev_data_pek_cert_import data;
592 void *pek_blob, *oca_blob;
593 int ret;
594
595 if (!writable)
596 return -EPERM;
597
598 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
599 return -EFAULT;
600
601 /* copy PEK certificate blobs from userspace */
602 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len);
603 if (IS_ERR(pek_blob))
604 return PTR_ERR(pek_blob);
605
606 data.reserved = 0;
607 data.pek_cert_address = __psp_pa(pek_blob);
608 data.pek_cert_len = input.pek_cert_len;
609
610 /* copy PEK certificate blobs from userspace */
611 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len);
612 if (IS_ERR(oca_blob)) {
613 ret = PTR_ERR(oca_blob);
614 goto e_free_pek;
615 }
616
617 data.oca_cert_address = __psp_pa(oca_blob);
618 data.oca_cert_len = input.oca_cert_len;
619
620 /* If platform is not in INIT state then transition it to INIT */
621 if (sev->state != SEV_STATE_INIT) {
622 ret = __sev_platform_init_locked(&argp->error);
623 if (ret)
624 goto e_free_oca;
625 }
626
627 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error);
628
629 e_free_oca:
630 kfree(oca_blob);
631 e_free_pek:
632 kfree(pek_blob);
633 return ret;
634 }
635
sev_ioctl_do_get_id2(struct sev_issue_cmd * argp)636 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp)
637 {
638 struct sev_user_data_get_id2 input;
639 struct sev_data_get_id data;
640 void __user *input_address;
641 void *id_blob = NULL;
642 int ret;
643
644 /* SEV GET_ID is available from SEV API v0.16 and up */
645 if (!sev_version_greater_or_equal(0, 16))
646 return -ENOTSUPP;
647
648 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
649 return -EFAULT;
650
651 input_address = (void __user *)input.address;
652
653 if (input.address && input.length) {
654 id_blob = kmalloc(input.length, GFP_KERNEL);
655 if (!id_blob)
656 return -ENOMEM;
657
658 data.address = __psp_pa(id_blob);
659 data.len = input.length;
660 } else {
661 data.address = 0;
662 data.len = 0;
663 }
664
665 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error);
666
667 /*
668 * Firmware will return the length of the ID value (either the minimum
669 * required length or the actual length written), return it to the user.
670 */
671 input.length = data.len;
672
673 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
674 ret = -EFAULT;
675 goto e_free;
676 }
677
678 if (id_blob) {
679 if (copy_to_user(input_address, id_blob, data.len)) {
680 ret = -EFAULT;
681 goto e_free;
682 }
683 }
684
685 e_free:
686 kfree(id_blob);
687
688 return ret;
689 }
690
sev_ioctl_do_get_id(struct sev_issue_cmd * argp)691 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp)
692 {
693 struct sev_data_get_id *data;
694 u64 data_size, user_size;
695 void *id_blob, *mem;
696 int ret;
697
698 /* SEV GET_ID available from SEV API v0.16 and up */
699 if (!sev_version_greater_or_equal(0, 16))
700 return -ENOTSUPP;
701
702 /* SEV FW expects the buffer it fills with the ID to be
703 * 8-byte aligned. Memory allocated should be enough to
704 * hold data structure + alignment padding + memory
705 * where SEV FW writes the ID.
706 */
707 data_size = ALIGN(sizeof(struct sev_data_get_id), 8);
708 user_size = sizeof(struct sev_user_data_get_id);
709
710 mem = kzalloc(data_size + user_size, GFP_KERNEL);
711 if (!mem)
712 return -ENOMEM;
713
714 data = mem;
715 id_blob = mem + data_size;
716
717 data->address = __psp_pa(id_blob);
718 data->len = user_size;
719
720 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error);
721 if (!ret) {
722 if (copy_to_user((void __user *)argp->data, id_blob, data->len))
723 ret = -EFAULT;
724 }
725
726 kfree(mem);
727
728 return ret;
729 }
730
sev_ioctl_do_pdh_export(struct sev_issue_cmd * argp,bool writable)731 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable)
732 {
733 struct sev_device *sev = psp_master->sev_data;
734 struct sev_user_data_pdh_cert_export input;
735 void *pdh_blob = NULL, *cert_blob = NULL;
736 struct sev_data_pdh_cert_export data;
737 void __user *input_cert_chain_address;
738 void __user *input_pdh_cert_address;
739 int ret;
740
741 /* If platform is not in INIT state then transition it to INIT. */
742 if (sev->state != SEV_STATE_INIT) {
743 if (!writable)
744 return -EPERM;
745
746 ret = __sev_platform_init_locked(&argp->error);
747 if (ret)
748 return ret;
749 }
750
751 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input)))
752 return -EFAULT;
753
754 memset(&data, 0, sizeof(data));
755
756 /* Userspace wants to query the certificate length. */
757 if (!input.pdh_cert_address ||
758 !input.pdh_cert_len ||
759 !input.cert_chain_address)
760 goto cmd;
761
762 input_pdh_cert_address = (void __user *)input.pdh_cert_address;
763 input_cert_chain_address = (void __user *)input.cert_chain_address;
764
765 /* Allocate a physically contiguous buffer to store the PDH blob. */
766 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE)
767 return -EFAULT;
768
769 /* Allocate a physically contiguous buffer to store the cert chain blob. */
770 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE)
771 return -EFAULT;
772
773 pdh_blob = kmalloc(input.pdh_cert_len, GFP_KERNEL);
774 if (!pdh_blob)
775 return -ENOMEM;
776
777 data.pdh_cert_address = __psp_pa(pdh_blob);
778 data.pdh_cert_len = input.pdh_cert_len;
779
780 cert_blob = kmalloc(input.cert_chain_len, GFP_KERNEL);
781 if (!cert_blob) {
782 ret = -ENOMEM;
783 goto e_free_pdh;
784 }
785
786 data.cert_chain_address = __psp_pa(cert_blob);
787 data.cert_chain_len = input.cert_chain_len;
788
789 cmd:
790 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error);
791
792 /* If we query the length, FW responded with expected data. */
793 input.cert_chain_len = data.cert_chain_len;
794 input.pdh_cert_len = data.pdh_cert_len;
795
796 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) {
797 ret = -EFAULT;
798 goto e_free_cert;
799 }
800
801 if (pdh_blob) {
802 if (copy_to_user(input_pdh_cert_address,
803 pdh_blob, input.pdh_cert_len)) {
804 ret = -EFAULT;
805 goto e_free_cert;
806 }
807 }
808
809 if (cert_blob) {
810 if (copy_to_user(input_cert_chain_address,
811 cert_blob, input.cert_chain_len))
812 ret = -EFAULT;
813 }
814
815 e_free_cert:
816 kfree(cert_blob);
817 e_free_pdh:
818 kfree(pdh_blob);
819 return ret;
820 }
821
sev_ioctl(struct file * file,unsigned int ioctl,unsigned long arg)822 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
823 {
824 void __user *argp = (void __user *)arg;
825 struct sev_issue_cmd input;
826 int ret = -EFAULT;
827 bool writable = file->f_mode & FMODE_WRITE;
828
829 if (!psp_master || !psp_master->sev_data)
830 return -ENODEV;
831
832 if (ioctl != SEV_ISSUE_CMD)
833 return -EINVAL;
834
835 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd)))
836 return -EFAULT;
837
838 if (input.cmd > SEV_MAX)
839 return -EINVAL;
840
841 mutex_lock(&sev_cmd_mutex);
842
843 switch (input.cmd) {
844
845 case SEV_FACTORY_RESET:
846 ret = sev_ioctl_do_reset(&input, writable);
847 break;
848 case SEV_PLATFORM_STATUS:
849 ret = sev_ioctl_do_platform_status(&input);
850 break;
851 case SEV_PEK_GEN:
852 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable);
853 break;
854 case SEV_PDH_GEN:
855 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable);
856 break;
857 case SEV_PEK_CSR:
858 ret = sev_ioctl_do_pek_csr(&input, writable);
859 break;
860 case SEV_PEK_CERT_IMPORT:
861 ret = sev_ioctl_do_pek_import(&input, writable);
862 break;
863 case SEV_PDH_CERT_EXPORT:
864 ret = sev_ioctl_do_pdh_export(&input, writable);
865 break;
866 case SEV_GET_ID:
867 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n");
868 ret = sev_ioctl_do_get_id(&input);
869 break;
870 case SEV_GET_ID2:
871 ret = sev_ioctl_do_get_id2(&input);
872 break;
873 default:
874 ret = -EINVAL;
875 goto out;
876 }
877
878 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))
879 ret = -EFAULT;
880 out:
881 mutex_unlock(&sev_cmd_mutex);
882
883 return ret;
884 }
885
886 static const struct file_operations sev_fops = {
887 .owner = THIS_MODULE,
888 .unlocked_ioctl = sev_ioctl,
889 };
890
sev_platform_status(struct sev_user_data_status * data,int * error)891 int sev_platform_status(struct sev_user_data_status *data, int *error)
892 {
893 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error);
894 }
895 EXPORT_SYMBOL_GPL(sev_platform_status);
896
sev_guest_deactivate(struct sev_data_deactivate * data,int * error)897 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error)
898 {
899 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error);
900 }
901 EXPORT_SYMBOL_GPL(sev_guest_deactivate);
902
sev_guest_activate(struct sev_data_activate * data,int * error)903 int sev_guest_activate(struct sev_data_activate *data, int *error)
904 {
905 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error);
906 }
907 EXPORT_SYMBOL_GPL(sev_guest_activate);
908
sev_guest_decommission(struct sev_data_decommission * data,int * error)909 int sev_guest_decommission(struct sev_data_decommission *data, int *error)
910 {
911 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error);
912 }
913 EXPORT_SYMBOL_GPL(sev_guest_decommission);
914
sev_guest_df_flush(int * error)915 int sev_guest_df_flush(int *error)
916 {
917 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error);
918 }
919 EXPORT_SYMBOL_GPL(sev_guest_df_flush);
920
sev_exit(struct kref * ref)921 static void sev_exit(struct kref *ref)
922 {
923 misc_deregister(&misc_dev->misc);
924 kfree(misc_dev);
925 misc_dev = NULL;
926 }
927
sev_misc_init(struct sev_device * sev)928 static int sev_misc_init(struct sev_device *sev)
929 {
930 struct device *dev = sev->dev;
931 int ret;
932
933 /*
934 * SEV feature support can be detected on multiple devices but the SEV
935 * FW commands must be issued on the master. During probe, we do not
936 * know the master hence we create /dev/sev on the first device probe.
937 * sev_do_cmd() finds the right master device to which to issue the
938 * command to the firmware.
939 */
940 if (!misc_dev) {
941 struct miscdevice *misc;
942
943 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL);
944 if (!misc_dev)
945 return -ENOMEM;
946
947 misc = &misc_dev->misc;
948 misc->minor = MISC_DYNAMIC_MINOR;
949 misc->name = DEVICE_NAME;
950 misc->fops = &sev_fops;
951
952 ret = misc_register(misc);
953 if (ret)
954 return ret;
955
956 kref_init(&misc_dev->refcount);
957 } else {
958 kref_get(&misc_dev->refcount);
959 }
960
961 init_waitqueue_head(&sev->int_queue);
962 sev->misc = misc_dev;
963 dev_dbg(dev, "registered SEV device\n");
964
965 return 0;
966 }
967
sev_dev_init(struct psp_device * psp)968 int sev_dev_init(struct psp_device *psp)
969 {
970 struct device *dev = psp->dev;
971 struct sev_device *sev;
972 int ret = -ENOMEM;
973
974 if (!boot_cpu_has(X86_FEATURE_SEV)) {
975 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n");
976 return 0;
977 }
978
979 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL);
980 if (!sev)
981 goto e_err;
982
983 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0);
984 if (!sev->cmd_buf)
985 goto e_sev;
986
987 psp->sev_data = sev;
988
989 sev->dev = dev;
990 sev->psp = psp;
991
992 sev->io_regs = psp->io_regs;
993
994 sev->vdata = (struct sev_vdata *)psp->vdata->sev;
995 if (!sev->vdata) {
996 ret = -ENODEV;
997 dev_err(dev, "sev: missing driver data\n");
998 goto e_buf;
999 }
1000
1001 psp_set_sev_irq_handler(psp, sev_irq_handler, sev);
1002
1003 ret = sev_misc_init(sev);
1004 if (ret)
1005 goto e_irq;
1006
1007 dev_notice(dev, "sev enabled\n");
1008
1009 return 0;
1010
1011 e_irq:
1012 psp_clear_sev_irq_handler(psp);
1013 e_buf:
1014 devm_free_pages(dev, (unsigned long)sev->cmd_buf);
1015 e_sev:
1016 devm_kfree(dev, sev);
1017 e_err:
1018 psp->sev_data = NULL;
1019
1020 dev_notice(dev, "sev initialization failed\n");
1021
1022 return ret;
1023 }
1024
sev_firmware_shutdown(struct sev_device * sev)1025 static void sev_firmware_shutdown(struct sev_device *sev)
1026 {
1027 sev_platform_shutdown(NULL);
1028
1029 if (sev_es_tmr) {
1030 /* The TMR area was encrypted, flush it from the cache */
1031 wbinvd_on_all_cpus();
1032
1033 free_pages((unsigned long)sev_es_tmr,
1034 get_order(SEV_ES_TMR_SIZE));
1035 sev_es_tmr = NULL;
1036 }
1037 }
1038
sev_dev_destroy(struct psp_device * psp)1039 void sev_dev_destroy(struct psp_device *psp)
1040 {
1041 struct sev_device *sev = psp->sev_data;
1042
1043 if (!sev)
1044 return;
1045
1046 sev_firmware_shutdown(sev);
1047
1048 if (sev->misc)
1049 kref_put(&misc_dev->refcount, sev_exit);
1050
1051 psp_clear_sev_irq_handler(psp);
1052 }
1053
sev_issue_cmd_external_user(struct file * filep,unsigned int cmd,void * data,int * error)1054 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd,
1055 void *data, int *error)
1056 {
1057 if (!filep || filep->f_op != &sev_fops)
1058 return -EBADF;
1059
1060 return sev_do_cmd(cmd, data, error);
1061 }
1062 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user);
1063
sev_pci_init(void)1064 void sev_pci_init(void)
1065 {
1066 struct sev_device *sev = psp_master->sev_data;
1067 struct page *tmr_page;
1068 int error, rc;
1069
1070 if (!sev)
1071 return;
1072
1073 psp_timeout = psp_probe_timeout;
1074
1075 if (sev_get_api_version())
1076 goto err;
1077
1078 if (sev_version_greater_or_equal(0, 15) &&
1079 sev_update_firmware(sev->dev) == 0)
1080 sev_get_api_version();
1081
1082 /* Obtain the TMR memory area for SEV-ES use */
1083 tmr_page = alloc_pages(GFP_KERNEL, get_order(SEV_ES_TMR_SIZE));
1084 if (tmr_page) {
1085 sev_es_tmr = page_address(tmr_page);
1086 } else {
1087 sev_es_tmr = NULL;
1088 dev_warn(sev->dev,
1089 "SEV: TMR allocation failed, SEV-ES support unavailable\n");
1090 }
1091
1092 /* Initialize the platform */
1093 rc = sev_platform_init(&error);
1094 if (rc && (error == SEV_RET_SECURE_DATA_INVALID)) {
1095 /*
1096 * INIT command returned an integrity check failure
1097 * status code, meaning that firmware load and
1098 * validation of SEV related persistent data has
1099 * failed and persistent state has been erased.
1100 * Retrying INIT command here should succeed.
1101 */
1102 dev_dbg(sev->dev, "SEV: retrying INIT command");
1103 rc = sev_platform_init(&error);
1104 }
1105
1106 if (rc) {
1107 dev_err(sev->dev, "SEV: failed to INIT error %#x\n", error);
1108 return;
1109 }
1110
1111 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major,
1112 sev->api_minor, sev->build);
1113
1114 return;
1115
1116 err:
1117 psp_master->sev_data = NULL;
1118 }
1119
sev_pci_exit(void)1120 void sev_pci_exit(void)
1121 {
1122 struct sev_device *sev = psp_master->sev_data;
1123
1124 if (!sev)
1125 return;
1126
1127 sev_firmware_shutdown(sev);
1128 }
1129
