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/bitfield.h> 11 #include <linux/module.h> 12 #include <linux/kernel.h> 13 #include <linux/kthread.h> 14 #include <linux/sched.h> 15 #include <linux/interrupt.h> 16 #include <linux/spinlock.h> 17 #include <linux/spinlock_types.h> 18 #include <linux/types.h> 19 #include <linux/mutex.h> 20 #include <linux/delay.h> 21 #include <linux/hw_random.h> 22 #include <linux/ccp.h> 23 #include <linux/firmware.h> 24 #include <linux/gfp.h> 25 #include <linux/cpufeature.h> 26 #include <linux/fs.h> 27 #include <linux/fs_struct.h> 28 #include <linux/psp.h> 29 30 #include <asm/smp.h> 31 #include <asm/cacheflush.h> 32 33 #include "psp-dev.h" 34 #include "sev-dev.h" 35 36 #define DEVICE_NAME "sev" 37 #define SEV_FW_FILE "amd/sev.fw" 38 #define SEV_FW_NAME_SIZE 64 39 40 static DEFINE_MUTEX(sev_cmd_mutex); 41 static struct sev_misc_dev *misc_dev; 42 43 static int psp_cmd_timeout = 100; 44 module_param(psp_cmd_timeout, int, 0644); 45 MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); 46 47 static int psp_probe_timeout = 5; 48 module_param(psp_probe_timeout, int, 0644); 49 MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); 50 51 static char *init_ex_path; 52 module_param(init_ex_path, charp, 0444); 53 MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); 54 55 static bool psp_init_on_probe = true; 56 module_param(psp_init_on_probe, bool, 0444); 57 MODULE_PARM_DESC(psp_init_on_probe, " if true, the PSP will be initialized on module init. Else the PSP will be initialized on the first command requiring it"); 58 59 MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ 60 MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ 61 MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ 62 MODULE_FIRMWARE("amd/amd_sev_fam19h_model1xh.sbin"); /* 4th gen EPYC */ 63 64 static bool psp_dead; 65 static int psp_timeout; 66 67 /* Trusted Memory Region (TMR): 68 * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator 69 * to allocate the memory, which will return aligned memory for the specified 70 * allocation order. 71 */ 72 #define SEV_ES_TMR_SIZE (1024 * 1024) 73 static void *sev_es_tmr; 74 75 /* INIT_EX NV Storage: 76 * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page 77 * allocator to allocate the memory, which will return aligned memory for the 78 * specified allocation order. 79 */ 80 #define NV_LENGTH (32 * 1024) 81 static void *sev_init_ex_buffer; 82 83 static inline bool sev_version_greater_or_equal(u8 maj, u8 min) 84 { 85 struct sev_device *sev = psp_master->sev_data; 86 87 if (sev->api_major > maj) 88 return true; 89 90 if (sev->api_major == maj && sev->api_minor >= min) 91 return true; 92 93 return false; 94 } 95 96 static void sev_irq_handler(int irq, void *data, unsigned int status) 97 { 98 struct sev_device *sev = data; 99 int reg; 100 101 /* Check if it is command completion: */ 102 if (!(status & SEV_CMD_COMPLETE)) 103 return; 104 105 /* Check if it is SEV command completion: */ 106 reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 107 if (FIELD_GET(PSP_CMDRESP_RESP, reg)) { 108 sev->int_rcvd = 1; 109 wake_up(&sev->int_queue); 110 } 111 } 112 113 static int sev_wait_cmd_ioc(struct sev_device *sev, 114 unsigned int *reg, unsigned int timeout) 115 { 116 int ret; 117 118 ret = wait_event_timeout(sev->int_queue, 119 sev->int_rcvd, timeout * HZ); 120 if (!ret) 121 return -ETIMEDOUT; 122 123 *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); 124 125 return 0; 126 } 127 128 static int sev_cmd_buffer_len(int cmd) 129 { 130 switch (cmd) { 131 case SEV_CMD_INIT: return sizeof(struct sev_data_init); 132 case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); 133 case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); 134 case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); 135 case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); 136 case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); 137 case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); 138 case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); 139 case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); 140 case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); 141 case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); 142 case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); 143 case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); 144 case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); 145 case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); 146 case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); 147 case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); 148 case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); 149 case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); 150 case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); 151 case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); 152 case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); 153 case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); 154 case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); 155 case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); 156 case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); 157 case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); 158 case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); 159 case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); 160 case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); 161 default: return 0; 162 } 163 164 return 0; 165 } 166 167 static void *sev_fw_alloc(unsigned long len) 168 { 169 struct page *page; 170 171 page = alloc_pages(GFP_KERNEL, get_order(len)); 172 if (!page) 173 return NULL; 174 175 return page_address(page); 176 } 177 178 static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) 179 { 180 struct file *fp; 181 struct path root; 182 struct cred *cred; 183 const struct cred *old_cred; 184 185 task_lock(&init_task); 186 get_fs_root(init_task.fs, &root); 187 task_unlock(&init_task); 188 189 cred = prepare_creds(); 190 if (!cred) 191 return ERR_PTR(-ENOMEM); 192 cred->fsuid = GLOBAL_ROOT_UID; 193 old_cred = override_creds(cred); 194 195 fp = file_open_root(&root, filename, flags, mode); 196 path_put(&root); 197 198 revert_creds(old_cred); 199 200 return fp; 201 } 202 203 static int sev_read_init_ex_file(void) 204 { 205 struct sev_device *sev = psp_master->sev_data; 206 struct file *fp; 207 ssize_t nread; 208 209 lockdep_assert_held(&sev_cmd_mutex); 210 211 if (!sev_init_ex_buffer) 212 return -EOPNOTSUPP; 213 214 fp = open_file_as_root(init_ex_path, O_RDONLY, 0); 215 if (IS_ERR(fp)) { 216 int ret = PTR_ERR(fp); 217 218 if (ret == -ENOENT) { 219 dev_info(sev->dev, 220 "SEV: %s does not exist and will be created later.\n", 221 init_ex_path); 222 ret = 0; 223 } else { 224 dev_err(sev->dev, 225 "SEV: could not open %s for read, error %d\n", 226 init_ex_path, ret); 227 } 228 return ret; 229 } 230 231 nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); 232 if (nread != NV_LENGTH) { 233 dev_info(sev->dev, 234 "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", 235 NV_LENGTH, nread); 236 } 237 238 dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); 239 filp_close(fp, NULL); 240 241 return 0; 242 } 243 244 static int sev_write_init_ex_file(void) 245 { 246 struct sev_device *sev = psp_master->sev_data; 247 struct file *fp; 248 loff_t offset = 0; 249 ssize_t nwrite; 250 251 lockdep_assert_held(&sev_cmd_mutex); 252 253 if (!sev_init_ex_buffer) 254 return 0; 255 256 fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); 257 if (IS_ERR(fp)) { 258 int ret = PTR_ERR(fp); 259 260 dev_err(sev->dev, 261 "SEV: could not open file for write, error %d\n", 262 ret); 263 return ret; 264 } 265 266 nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); 267 vfs_fsync(fp, 0); 268 filp_close(fp, NULL); 269 270 if (nwrite != NV_LENGTH) { 271 dev_err(sev->dev, 272 "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", 273 NV_LENGTH, nwrite); 274 return -EIO; 275 } 276 277 dev_dbg(sev->dev, "SEV: write successful to NV file\n"); 278 279 return 0; 280 } 281 282 static int sev_write_init_ex_file_if_required(int cmd_id) 283 { 284 lockdep_assert_held(&sev_cmd_mutex); 285 286 if (!sev_init_ex_buffer) 287 return 0; 288 289 /* 290 * Only a few platform commands modify the SPI/NV area, but none of the 291 * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, 292 * PEK_CERT_IMPORT, and PDH_GEN do. 293 */ 294 switch (cmd_id) { 295 case SEV_CMD_FACTORY_RESET: 296 case SEV_CMD_INIT_EX: 297 case SEV_CMD_PDH_GEN: 298 case SEV_CMD_PEK_CERT_IMPORT: 299 case SEV_CMD_PEK_GEN: 300 break; 301 default: 302 return 0; 303 } 304 305 return sev_write_init_ex_file(); 306 } 307 308 static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) 309 { 310 struct psp_device *psp = psp_master; 311 struct sev_device *sev; 312 unsigned int phys_lsb, phys_msb; 313 unsigned int reg, ret = 0; 314 int buf_len; 315 316 if (!psp || !psp->sev_data) 317 return -ENODEV; 318 319 if (psp_dead) 320 return -EBUSY; 321 322 sev = psp->sev_data; 323 324 buf_len = sev_cmd_buffer_len(cmd); 325 if (WARN_ON_ONCE(!data != !buf_len)) 326 return -EINVAL; 327 328 /* 329 * Copy the incoming data to driver's scratch buffer as __pa() will not 330 * work for some memory, e.g. vmalloc'd addresses, and @data may not be 331 * physically contiguous. 332 */ 333 if (data) 334 memcpy(sev->cmd_buf, data, buf_len); 335 336 /* Get the physical address of the command buffer */ 337 phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0; 338 phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0; 339 340 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", 341 cmd, phys_msb, phys_lsb, psp_timeout); 342 343 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, 344 buf_len, false); 345 346 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 347 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 348 349 sev->int_rcvd = 0; 350 351 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd) | SEV_CMDRESP_IOC; 352 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); 353 354 /* wait for command completion */ 355 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); 356 if (ret) { 357 if (psp_ret) 358 *psp_ret = 0; 359 360 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); 361 psp_dead = true; 362 363 return ret; 364 } 365 366 psp_timeout = psp_cmd_timeout; 367 368 if (psp_ret) 369 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); 370 371 if (FIELD_GET(PSP_CMDRESP_STS, reg)) { 372 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", 373 cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); 374 ret = -EIO; 375 } else { 376 ret = sev_write_init_ex_file_if_required(cmd); 377 } 378 379 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, 380 buf_len, false); 381 382 /* 383 * Copy potential output from the PSP back to data. Do this even on 384 * failure in case the caller wants to glean something from the error. 385 */ 386 if (data) 387 memcpy(data, sev->cmd_buf, buf_len); 388 389 return ret; 390 } 391 392 static int sev_do_cmd(int cmd, void *data, int *psp_ret) 393 { 394 int rc; 395 396 mutex_lock(&sev_cmd_mutex); 397 rc = __sev_do_cmd_locked(cmd, data, psp_ret); 398 mutex_unlock(&sev_cmd_mutex); 399 400 return rc; 401 } 402 403 static int __sev_init_locked(int *error) 404 { 405 struct sev_data_init data; 406 407 memset(&data, 0, sizeof(data)); 408 if (sev_es_tmr) { 409 /* 410 * Do not include the encryption mask on the physical 411 * address of the TMR (firmware should clear it anyway). 412 */ 413 data.tmr_address = __pa(sev_es_tmr); 414 415 data.flags |= SEV_INIT_FLAGS_SEV_ES; 416 data.tmr_len = SEV_ES_TMR_SIZE; 417 } 418 419 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); 420 } 421 422 static int __sev_init_ex_locked(int *error) 423 { 424 struct sev_data_init_ex data; 425 426 memset(&data, 0, sizeof(data)); 427 data.length = sizeof(data); 428 data.nv_address = __psp_pa(sev_init_ex_buffer); 429 data.nv_len = NV_LENGTH; 430 431 if (sev_es_tmr) { 432 /* 433 * Do not include the encryption mask on the physical 434 * address of the TMR (firmware should clear it anyway). 435 */ 436 data.tmr_address = __pa(sev_es_tmr); 437 438 data.flags |= SEV_INIT_FLAGS_SEV_ES; 439 data.tmr_len = SEV_ES_TMR_SIZE; 440 } 441 442 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); 443 } 444 445 static inline int __sev_do_init_locked(int *psp_ret) 446 { 447 if (sev_init_ex_buffer) 448 return __sev_init_ex_locked(psp_ret); 449 else 450 return __sev_init_locked(psp_ret); 451 } 452 453 static int __sev_platform_init_locked(int *error) 454 { 455 int rc = 0, psp_ret = SEV_RET_NO_FW_CALL; 456 struct psp_device *psp = psp_master; 457 struct sev_device *sev; 458 459 if (!psp || !psp->sev_data) 460 return -ENODEV; 461 462 sev = psp->sev_data; 463 464 if (sev->state == SEV_STATE_INIT) 465 return 0; 466 467 if (sev_init_ex_buffer) { 468 rc = sev_read_init_ex_file(); 469 if (rc) 470 return rc; 471 } 472 473 rc = __sev_do_init_locked(&psp_ret); 474 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { 475 /* 476 * Initialization command returned an integrity check failure 477 * status code, meaning that firmware load and validation of SEV 478 * related persistent data has failed. Retrying the 479 * initialization function should succeed by replacing the state 480 * with a reset state. 481 */ 482 dev_err(sev->dev, 483 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); 484 rc = __sev_do_init_locked(&psp_ret); 485 } 486 487 if (error) 488 *error = psp_ret; 489 490 if (rc) 491 return rc; 492 493 sev->state = SEV_STATE_INIT; 494 495 /* Prepare for first SEV guest launch after INIT */ 496 wbinvd_on_all_cpus(); 497 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error); 498 if (rc) 499 return rc; 500 501 dev_dbg(sev->dev, "SEV firmware initialized\n"); 502 503 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, 504 sev->api_minor, sev->build); 505 506 return 0; 507 } 508 509 int sev_platform_init(int *error) 510 { 511 int rc; 512 513 mutex_lock(&sev_cmd_mutex); 514 rc = __sev_platform_init_locked(error); 515 mutex_unlock(&sev_cmd_mutex); 516 517 return rc; 518 } 519 EXPORT_SYMBOL_GPL(sev_platform_init); 520 521 static int __sev_platform_shutdown_locked(int *error) 522 { 523 struct psp_device *psp = psp_master; 524 struct sev_device *sev; 525 int ret; 526 527 if (!psp || !psp->sev_data) 528 return 0; 529 530 sev = psp->sev_data; 531 532 if (sev->state == SEV_STATE_UNINIT) 533 return 0; 534 535 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); 536 if (ret) 537 return ret; 538 539 sev->state = SEV_STATE_UNINIT; 540 dev_dbg(sev->dev, "SEV firmware shutdown\n"); 541 542 return ret; 543 } 544 545 static int sev_platform_shutdown(int *error) 546 { 547 int rc; 548 549 mutex_lock(&sev_cmd_mutex); 550 rc = __sev_platform_shutdown_locked(NULL); 551 mutex_unlock(&sev_cmd_mutex); 552 553 return rc; 554 } 555 556 static int sev_get_platform_state(int *state, int *error) 557 { 558 struct sev_user_data_status data; 559 int rc; 560 561 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); 562 if (rc) 563 return rc; 564 565 *state = data.state; 566 return rc; 567 } 568 569 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) 570 { 571 int state, rc; 572 573 if (!writable) 574 return -EPERM; 575 576 /* 577 * The SEV spec requires that FACTORY_RESET must be issued in 578 * UNINIT state. Before we go further lets check if any guest is 579 * active. 580 * 581 * If FW is in WORKING state then deny the request otherwise issue 582 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. 583 * 584 */ 585 rc = sev_get_platform_state(&state, &argp->error); 586 if (rc) 587 return rc; 588 589 if (state == SEV_STATE_WORKING) 590 return -EBUSY; 591 592 if (state == SEV_STATE_INIT) { 593 rc = __sev_platform_shutdown_locked(&argp->error); 594 if (rc) 595 return rc; 596 } 597 598 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); 599 } 600 601 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) 602 { 603 struct sev_user_data_status data; 604 int ret; 605 606 memset(&data, 0, sizeof(data)); 607 608 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); 609 if (ret) 610 return ret; 611 612 if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) 613 ret = -EFAULT; 614 615 return ret; 616 } 617 618 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) 619 { 620 struct sev_device *sev = psp_master->sev_data; 621 int rc; 622 623 if (!writable) 624 return -EPERM; 625 626 if (sev->state == SEV_STATE_UNINIT) { 627 rc = __sev_platform_init_locked(&argp->error); 628 if (rc) 629 return rc; 630 } 631 632 return __sev_do_cmd_locked(cmd, NULL, &argp->error); 633 } 634 635 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) 636 { 637 struct sev_device *sev = psp_master->sev_data; 638 struct sev_user_data_pek_csr input; 639 struct sev_data_pek_csr data; 640 void __user *input_address; 641 void *blob = NULL; 642 int ret; 643 644 if (!writable) 645 return -EPERM; 646 647 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 648 return -EFAULT; 649 650 memset(&data, 0, sizeof(data)); 651 652 /* userspace wants to query CSR length */ 653 if (!input.address || !input.length) 654 goto cmd; 655 656 /* allocate a physically contiguous buffer to store the CSR blob */ 657 input_address = (void __user *)input.address; 658 if (input.length > SEV_FW_BLOB_MAX_SIZE) 659 return -EFAULT; 660 661 blob = kzalloc(input.length, GFP_KERNEL); 662 if (!blob) 663 return -ENOMEM; 664 665 data.address = __psp_pa(blob); 666 data.len = input.length; 667 668 cmd: 669 if (sev->state == SEV_STATE_UNINIT) { 670 ret = __sev_platform_init_locked(&argp->error); 671 if (ret) 672 goto e_free_blob; 673 } 674 675 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); 676 677 /* If we query the CSR length, FW responded with expected data. */ 678 input.length = data.len; 679 680 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 681 ret = -EFAULT; 682 goto e_free_blob; 683 } 684 685 if (blob) { 686 if (copy_to_user(input_address, blob, input.length)) 687 ret = -EFAULT; 688 } 689 690 e_free_blob: 691 kfree(blob); 692 return ret; 693 } 694 695 void *psp_copy_user_blob(u64 uaddr, u32 len) 696 { 697 if (!uaddr || !len) 698 return ERR_PTR(-EINVAL); 699 700 /* verify that blob length does not exceed our limit */ 701 if (len > SEV_FW_BLOB_MAX_SIZE) 702 return ERR_PTR(-EINVAL); 703 704 return memdup_user((void __user *)uaddr, len); 705 } 706 EXPORT_SYMBOL_GPL(psp_copy_user_blob); 707 708 static int sev_get_api_version(void) 709 { 710 struct sev_device *sev = psp_master->sev_data; 711 struct sev_user_data_status status; 712 int error = 0, ret; 713 714 ret = sev_platform_status(&status, &error); 715 if (ret) { 716 dev_err(sev->dev, 717 "SEV: failed to get status. Error: %#x\n", error); 718 return 1; 719 } 720 721 sev->api_major = status.api_major; 722 sev->api_minor = status.api_minor; 723 sev->build = status.build; 724 sev->state = status.state; 725 726 return 0; 727 } 728 729 static int sev_get_firmware(struct device *dev, 730 const struct firmware **firmware) 731 { 732 char fw_name_specific[SEV_FW_NAME_SIZE]; 733 char fw_name_subset[SEV_FW_NAME_SIZE]; 734 735 snprintf(fw_name_specific, sizeof(fw_name_specific), 736 "amd/amd_sev_fam%.2xh_model%.2xh.sbin", 737 boot_cpu_data.x86, boot_cpu_data.x86_model); 738 739 snprintf(fw_name_subset, sizeof(fw_name_subset), 740 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", 741 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); 742 743 /* Check for SEV FW for a particular model. 744 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h 745 * 746 * or 747 * 748 * Check for SEV FW common to a subset of models. 749 * Ex. amd_sev_fam17h_model0xh.sbin for 750 * Family 17h Model 00h -- Family 17h Model 0Fh 751 * 752 * or 753 * 754 * Fall-back to using generic name: sev.fw 755 */ 756 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || 757 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || 758 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) 759 return 0; 760 761 return -ENOENT; 762 } 763 764 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ 765 static int sev_update_firmware(struct device *dev) 766 { 767 struct sev_data_download_firmware *data; 768 const struct firmware *firmware; 769 int ret, error, order; 770 struct page *p; 771 u64 data_size; 772 773 if (!sev_version_greater_or_equal(0, 15)) { 774 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); 775 return -1; 776 } 777 778 if (sev_get_firmware(dev, &firmware) == -ENOENT) { 779 dev_dbg(dev, "No SEV firmware file present\n"); 780 return -1; 781 } 782 783 /* 784 * SEV FW expects the physical address given to it to be 32 785 * byte aligned. Memory allocated has structure placed at the 786 * beginning followed by the firmware being passed to the SEV 787 * FW. Allocate enough memory for data structure + alignment 788 * padding + SEV FW. 789 */ 790 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32); 791 792 order = get_order(firmware->size + data_size); 793 p = alloc_pages(GFP_KERNEL, order); 794 if (!p) { 795 ret = -1; 796 goto fw_err; 797 } 798 799 /* 800 * Copy firmware data to a kernel allocated contiguous 801 * memory region. 802 */ 803 data = page_address(p); 804 memcpy(page_address(p) + data_size, firmware->data, firmware->size); 805 806 data->address = __psp_pa(page_address(p) + data_size); 807 data->len = firmware->size; 808 809 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 810 811 /* 812 * A quirk for fixing the committed TCB version, when upgrading from 813 * earlier firmware version than 1.50. 814 */ 815 if (!ret && !sev_version_greater_or_equal(1, 50)) 816 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 817 818 if (ret) 819 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); 820 else 821 dev_info(dev, "SEV firmware update successful\n"); 822 823 __free_pages(p, order); 824 825 fw_err: 826 release_firmware(firmware); 827 828 return ret; 829 } 830 831 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) 832 { 833 struct sev_device *sev = psp_master->sev_data; 834 struct sev_user_data_pek_cert_import input; 835 struct sev_data_pek_cert_import data; 836 void *pek_blob, *oca_blob; 837 int ret; 838 839 if (!writable) 840 return -EPERM; 841 842 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 843 return -EFAULT; 844 845 /* copy PEK certificate blobs from userspace */ 846 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); 847 if (IS_ERR(pek_blob)) 848 return PTR_ERR(pek_blob); 849 850 data.reserved = 0; 851 data.pek_cert_address = __psp_pa(pek_blob); 852 data.pek_cert_len = input.pek_cert_len; 853 854 /* copy PEK certificate blobs from userspace */ 855 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); 856 if (IS_ERR(oca_blob)) { 857 ret = PTR_ERR(oca_blob); 858 goto e_free_pek; 859 } 860 861 data.oca_cert_address = __psp_pa(oca_blob); 862 data.oca_cert_len = input.oca_cert_len; 863 864 /* If platform is not in INIT state then transition it to INIT */ 865 if (sev->state != SEV_STATE_INIT) { 866 ret = __sev_platform_init_locked(&argp->error); 867 if (ret) 868 goto e_free_oca; 869 } 870 871 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); 872 873 e_free_oca: 874 kfree(oca_blob); 875 e_free_pek: 876 kfree(pek_blob); 877 return ret; 878 } 879 880 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) 881 { 882 struct sev_user_data_get_id2 input; 883 struct sev_data_get_id data; 884 void __user *input_address; 885 void *id_blob = NULL; 886 int ret; 887 888 /* SEV GET_ID is available from SEV API v0.16 and up */ 889 if (!sev_version_greater_or_equal(0, 16)) 890 return -ENOTSUPP; 891 892 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 893 return -EFAULT; 894 895 input_address = (void __user *)input.address; 896 897 if (input.address && input.length) { 898 /* 899 * The length of the ID shouldn't be assumed by software since 900 * it may change in the future. The allocation size is limited 901 * to 1 << (PAGE_SHIFT + MAX_ORDER) by the page allocator. 902 * If the allocation fails, simply return ENOMEM rather than 903 * warning in the kernel log. 904 */ 905 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); 906 if (!id_blob) 907 return -ENOMEM; 908 909 data.address = __psp_pa(id_blob); 910 data.len = input.length; 911 } else { 912 data.address = 0; 913 data.len = 0; 914 } 915 916 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); 917 918 /* 919 * Firmware will return the length of the ID value (either the minimum 920 * required length or the actual length written), return it to the user. 921 */ 922 input.length = data.len; 923 924 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 925 ret = -EFAULT; 926 goto e_free; 927 } 928 929 if (id_blob) { 930 if (copy_to_user(input_address, id_blob, data.len)) { 931 ret = -EFAULT; 932 goto e_free; 933 } 934 } 935 936 e_free: 937 kfree(id_blob); 938 939 return ret; 940 } 941 942 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) 943 { 944 struct sev_data_get_id *data; 945 u64 data_size, user_size; 946 void *id_blob, *mem; 947 int ret; 948 949 /* SEV GET_ID available from SEV API v0.16 and up */ 950 if (!sev_version_greater_or_equal(0, 16)) 951 return -ENOTSUPP; 952 953 /* SEV FW expects the buffer it fills with the ID to be 954 * 8-byte aligned. Memory allocated should be enough to 955 * hold data structure + alignment padding + memory 956 * where SEV FW writes the ID. 957 */ 958 data_size = ALIGN(sizeof(struct sev_data_get_id), 8); 959 user_size = sizeof(struct sev_user_data_get_id); 960 961 mem = kzalloc(data_size + user_size, GFP_KERNEL); 962 if (!mem) 963 return -ENOMEM; 964 965 data = mem; 966 id_blob = mem + data_size; 967 968 data->address = __psp_pa(id_blob); 969 data->len = user_size; 970 971 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); 972 if (!ret) { 973 if (copy_to_user((void __user *)argp->data, id_blob, data->len)) 974 ret = -EFAULT; 975 } 976 977 kfree(mem); 978 979 return ret; 980 } 981 982 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) 983 { 984 struct sev_device *sev = psp_master->sev_data; 985 struct sev_user_data_pdh_cert_export input; 986 void *pdh_blob = NULL, *cert_blob = NULL; 987 struct sev_data_pdh_cert_export data; 988 void __user *input_cert_chain_address; 989 void __user *input_pdh_cert_address; 990 int ret; 991 992 /* If platform is not in INIT state then transition it to INIT. */ 993 if (sev->state != SEV_STATE_INIT) { 994 if (!writable) 995 return -EPERM; 996 997 ret = __sev_platform_init_locked(&argp->error); 998 if (ret) 999 return ret; 1000 } 1001 1002 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1003 return -EFAULT; 1004 1005 memset(&data, 0, sizeof(data)); 1006 1007 /* Userspace wants to query the certificate length. */ 1008 if (!input.pdh_cert_address || 1009 !input.pdh_cert_len || 1010 !input.cert_chain_address) 1011 goto cmd; 1012 1013 input_pdh_cert_address = (void __user *)input.pdh_cert_address; 1014 input_cert_chain_address = (void __user *)input.cert_chain_address; 1015 1016 /* Allocate a physically contiguous buffer to store the PDH blob. */ 1017 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) 1018 return -EFAULT; 1019 1020 /* Allocate a physically contiguous buffer to store the cert chain blob. */ 1021 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) 1022 return -EFAULT; 1023 1024 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); 1025 if (!pdh_blob) 1026 return -ENOMEM; 1027 1028 data.pdh_cert_address = __psp_pa(pdh_blob); 1029 data.pdh_cert_len = input.pdh_cert_len; 1030 1031 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); 1032 if (!cert_blob) { 1033 ret = -ENOMEM; 1034 goto e_free_pdh; 1035 } 1036 1037 data.cert_chain_address = __psp_pa(cert_blob); 1038 data.cert_chain_len = input.cert_chain_len; 1039 1040 cmd: 1041 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); 1042 1043 /* If we query the length, FW responded with expected data. */ 1044 input.cert_chain_len = data.cert_chain_len; 1045 input.pdh_cert_len = data.pdh_cert_len; 1046 1047 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1048 ret = -EFAULT; 1049 goto e_free_cert; 1050 } 1051 1052 if (pdh_blob) { 1053 if (copy_to_user(input_pdh_cert_address, 1054 pdh_blob, input.pdh_cert_len)) { 1055 ret = -EFAULT; 1056 goto e_free_cert; 1057 } 1058 } 1059 1060 if (cert_blob) { 1061 if (copy_to_user(input_cert_chain_address, 1062 cert_blob, input.cert_chain_len)) 1063 ret = -EFAULT; 1064 } 1065 1066 e_free_cert: 1067 kfree(cert_blob); 1068 e_free_pdh: 1069 kfree(pdh_blob); 1070 return ret; 1071 } 1072 1073 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) 1074 { 1075 void __user *argp = (void __user *)arg; 1076 struct sev_issue_cmd input; 1077 int ret = -EFAULT; 1078 bool writable = file->f_mode & FMODE_WRITE; 1079 1080 if (!psp_master || !psp_master->sev_data) 1081 return -ENODEV; 1082 1083 if (ioctl != SEV_ISSUE_CMD) 1084 return -EINVAL; 1085 1086 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) 1087 return -EFAULT; 1088 1089 if (input.cmd > SEV_MAX) 1090 return -EINVAL; 1091 1092 mutex_lock(&sev_cmd_mutex); 1093 1094 switch (input.cmd) { 1095 1096 case SEV_FACTORY_RESET: 1097 ret = sev_ioctl_do_reset(&input, writable); 1098 break; 1099 case SEV_PLATFORM_STATUS: 1100 ret = sev_ioctl_do_platform_status(&input); 1101 break; 1102 case SEV_PEK_GEN: 1103 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); 1104 break; 1105 case SEV_PDH_GEN: 1106 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); 1107 break; 1108 case SEV_PEK_CSR: 1109 ret = sev_ioctl_do_pek_csr(&input, writable); 1110 break; 1111 case SEV_PEK_CERT_IMPORT: 1112 ret = sev_ioctl_do_pek_import(&input, writable); 1113 break; 1114 case SEV_PDH_CERT_EXPORT: 1115 ret = sev_ioctl_do_pdh_export(&input, writable); 1116 break; 1117 case SEV_GET_ID: 1118 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); 1119 ret = sev_ioctl_do_get_id(&input); 1120 break; 1121 case SEV_GET_ID2: 1122 ret = sev_ioctl_do_get_id2(&input); 1123 break; 1124 default: 1125 ret = -EINVAL; 1126 goto out; 1127 } 1128 1129 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) 1130 ret = -EFAULT; 1131 out: 1132 mutex_unlock(&sev_cmd_mutex); 1133 1134 return ret; 1135 } 1136 1137 static const struct file_operations sev_fops = { 1138 .owner = THIS_MODULE, 1139 .unlocked_ioctl = sev_ioctl, 1140 }; 1141 1142 int sev_platform_status(struct sev_user_data_status *data, int *error) 1143 { 1144 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); 1145 } 1146 EXPORT_SYMBOL_GPL(sev_platform_status); 1147 1148 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) 1149 { 1150 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); 1151 } 1152 EXPORT_SYMBOL_GPL(sev_guest_deactivate); 1153 1154 int sev_guest_activate(struct sev_data_activate *data, int *error) 1155 { 1156 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); 1157 } 1158 EXPORT_SYMBOL_GPL(sev_guest_activate); 1159 1160 int sev_guest_decommission(struct sev_data_decommission *data, int *error) 1161 { 1162 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); 1163 } 1164 EXPORT_SYMBOL_GPL(sev_guest_decommission); 1165 1166 int sev_guest_df_flush(int *error) 1167 { 1168 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); 1169 } 1170 EXPORT_SYMBOL_GPL(sev_guest_df_flush); 1171 1172 static void sev_exit(struct kref *ref) 1173 { 1174 misc_deregister(&misc_dev->misc); 1175 kfree(misc_dev); 1176 misc_dev = NULL; 1177 } 1178 1179 static int sev_misc_init(struct sev_device *sev) 1180 { 1181 struct device *dev = sev->dev; 1182 int ret; 1183 1184 /* 1185 * SEV feature support can be detected on multiple devices but the SEV 1186 * FW commands must be issued on the master. During probe, we do not 1187 * know the master hence we create /dev/sev on the first device probe. 1188 * sev_do_cmd() finds the right master device to which to issue the 1189 * command to the firmware. 1190 */ 1191 if (!misc_dev) { 1192 struct miscdevice *misc; 1193 1194 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL); 1195 if (!misc_dev) 1196 return -ENOMEM; 1197 1198 misc = &misc_dev->misc; 1199 misc->minor = MISC_DYNAMIC_MINOR; 1200 misc->name = DEVICE_NAME; 1201 misc->fops = &sev_fops; 1202 1203 ret = misc_register(misc); 1204 if (ret) 1205 return ret; 1206 1207 kref_init(&misc_dev->refcount); 1208 } else { 1209 kref_get(&misc_dev->refcount); 1210 } 1211 1212 init_waitqueue_head(&sev->int_queue); 1213 sev->misc = misc_dev; 1214 dev_dbg(dev, "registered SEV device\n"); 1215 1216 return 0; 1217 } 1218 1219 int sev_dev_init(struct psp_device *psp) 1220 { 1221 struct device *dev = psp->dev; 1222 struct sev_device *sev; 1223 int ret = -ENOMEM; 1224 1225 if (!boot_cpu_has(X86_FEATURE_SEV)) { 1226 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); 1227 return 0; 1228 } 1229 1230 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); 1231 if (!sev) 1232 goto e_err; 1233 1234 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0); 1235 if (!sev->cmd_buf) 1236 goto e_sev; 1237 1238 psp->sev_data = sev; 1239 1240 sev->dev = dev; 1241 sev->psp = psp; 1242 1243 sev->io_regs = psp->io_regs; 1244 1245 sev->vdata = (struct sev_vdata *)psp->vdata->sev; 1246 if (!sev->vdata) { 1247 ret = -ENODEV; 1248 dev_err(dev, "sev: missing driver data\n"); 1249 goto e_buf; 1250 } 1251 1252 psp_set_sev_irq_handler(psp, sev_irq_handler, sev); 1253 1254 ret = sev_misc_init(sev); 1255 if (ret) 1256 goto e_irq; 1257 1258 dev_notice(dev, "sev enabled\n"); 1259 1260 return 0; 1261 1262 e_irq: 1263 psp_clear_sev_irq_handler(psp); 1264 e_buf: 1265 devm_free_pages(dev, (unsigned long)sev->cmd_buf); 1266 e_sev: 1267 devm_kfree(dev, sev); 1268 e_err: 1269 psp->sev_data = NULL; 1270 1271 dev_notice(dev, "sev initialization failed\n"); 1272 1273 return ret; 1274 } 1275 1276 static void sev_firmware_shutdown(struct sev_device *sev) 1277 { 1278 sev_platform_shutdown(NULL); 1279 1280 if (sev_es_tmr) { 1281 /* The TMR area was encrypted, flush it from the cache */ 1282 wbinvd_on_all_cpus(); 1283 1284 free_pages((unsigned long)sev_es_tmr, 1285 get_order(SEV_ES_TMR_SIZE)); 1286 sev_es_tmr = NULL; 1287 } 1288 1289 if (sev_init_ex_buffer) { 1290 free_pages((unsigned long)sev_init_ex_buffer, 1291 get_order(NV_LENGTH)); 1292 sev_init_ex_buffer = NULL; 1293 } 1294 } 1295 1296 void sev_dev_destroy(struct psp_device *psp) 1297 { 1298 struct sev_device *sev = psp->sev_data; 1299 1300 if (!sev) 1301 return; 1302 1303 sev_firmware_shutdown(sev); 1304 1305 if (sev->misc) 1306 kref_put(&misc_dev->refcount, sev_exit); 1307 1308 psp_clear_sev_irq_handler(psp); 1309 } 1310 1311 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, 1312 void *data, int *error) 1313 { 1314 if (!filep || filep->f_op != &sev_fops) 1315 return -EBADF; 1316 1317 return sev_do_cmd(cmd, data, error); 1318 } 1319 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); 1320 1321 void sev_pci_init(void) 1322 { 1323 struct sev_device *sev = psp_master->sev_data; 1324 int error, rc; 1325 1326 if (!sev) 1327 return; 1328 1329 psp_timeout = psp_probe_timeout; 1330 1331 if (sev_get_api_version()) 1332 goto err; 1333 1334 if (sev_update_firmware(sev->dev) == 0) 1335 sev_get_api_version(); 1336 1337 /* If an init_ex_path is provided rely on INIT_EX for PSP initialization 1338 * instead of INIT. 1339 */ 1340 if (init_ex_path) { 1341 sev_init_ex_buffer = sev_fw_alloc(NV_LENGTH); 1342 if (!sev_init_ex_buffer) { 1343 dev_err(sev->dev, 1344 "SEV: INIT_EX NV memory allocation failed\n"); 1345 goto err; 1346 } 1347 } 1348 1349 /* Obtain the TMR memory area for SEV-ES use */ 1350 sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE); 1351 if (sev_es_tmr) 1352 /* Must flush the cache before giving it to the firmware */ 1353 clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE); 1354 else 1355 dev_warn(sev->dev, 1356 "SEV: TMR allocation failed, SEV-ES support unavailable\n"); 1357 1358 if (!psp_init_on_probe) 1359 return; 1360 1361 /* Initialize the platform */ 1362 rc = sev_platform_init(&error); 1363 if (rc) 1364 dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n", 1365 error, rc); 1366 1367 return; 1368 1369 err: 1370 psp_master->sev_data = NULL; 1371 } 1372 1373 void sev_pci_exit(void) 1374 { 1375 struct sev_device *sev = psp_master->sev_data; 1376 1377 if (!sev) 1378 return; 1379 1380 sev_firmware_shutdown(sev); 1381 } 1382