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