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 cmdbuff_hi, cmdbuff_lo; 313 unsigned int phys_lsb, phys_msb; 314 unsigned int reg, ret = 0; 315 int buf_len; 316 317 if (!psp || !psp->sev_data) 318 return -ENODEV; 319 320 if (psp_dead) 321 return -EBUSY; 322 323 sev = psp->sev_data; 324 325 buf_len = sev_cmd_buffer_len(cmd); 326 if (WARN_ON_ONCE(!data != !buf_len)) 327 return -EINVAL; 328 329 /* 330 * Copy the incoming data to driver's scratch buffer as __pa() will not 331 * work for some memory, e.g. vmalloc'd addresses, and @data may not be 332 * physically contiguous. 333 */ 334 if (data) 335 memcpy(sev->cmd_buf, data, buf_len); 336 337 /* Get the physical address of the command buffer */ 338 phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0; 339 phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0; 340 341 dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", 342 cmd, phys_msb, phys_lsb, psp_timeout); 343 344 print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, 345 buf_len, false); 346 347 iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 348 iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 349 350 sev->int_rcvd = 0; 351 352 reg = FIELD_PREP(SEV_CMDRESP_CMD, cmd) | SEV_CMDRESP_IOC; 353 iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); 354 355 /* wait for command completion */ 356 ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); 357 if (ret) { 358 if (psp_ret) 359 *psp_ret = 0; 360 361 dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); 362 psp_dead = true; 363 364 return ret; 365 } 366 367 psp_timeout = psp_cmd_timeout; 368 369 if (psp_ret) 370 *psp_ret = FIELD_GET(PSP_CMDRESP_STS, reg); 371 372 if (FIELD_GET(PSP_CMDRESP_STS, reg)) { 373 dev_dbg(sev->dev, "sev command %#x failed (%#010lx)\n", 374 cmd, FIELD_GET(PSP_CMDRESP_STS, reg)); 375 376 /* 377 * PSP firmware may report additional error information in the 378 * command buffer registers on error. Print contents of command 379 * buffer registers if they changed. 380 */ 381 cmdbuff_hi = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); 382 cmdbuff_lo = ioread32(sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); 383 if (cmdbuff_hi != phys_msb || cmdbuff_lo != phys_lsb) { 384 dev_dbg(sev->dev, "Additional error information reported in cmdbuff:"); 385 dev_dbg(sev->dev, " cmdbuff hi: %#010x\n", cmdbuff_hi); 386 dev_dbg(sev->dev, " cmdbuff lo: %#010x\n", cmdbuff_lo); 387 } 388 ret = -EIO; 389 } else { 390 ret = sev_write_init_ex_file_if_required(cmd); 391 } 392 393 print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, 394 buf_len, false); 395 396 /* 397 * Copy potential output from the PSP back to data. Do this even on 398 * failure in case the caller wants to glean something from the error. 399 */ 400 if (data) 401 memcpy(data, sev->cmd_buf, buf_len); 402 403 return ret; 404 } 405 406 static int sev_do_cmd(int cmd, void *data, int *psp_ret) 407 { 408 int rc; 409 410 mutex_lock(&sev_cmd_mutex); 411 rc = __sev_do_cmd_locked(cmd, data, psp_ret); 412 mutex_unlock(&sev_cmd_mutex); 413 414 return rc; 415 } 416 417 static int __sev_init_locked(int *error) 418 { 419 struct sev_data_init data; 420 421 memset(&data, 0, sizeof(data)); 422 if (sev_es_tmr) { 423 /* 424 * Do not include the encryption mask on the physical 425 * address of the TMR (firmware should clear it anyway). 426 */ 427 data.tmr_address = __pa(sev_es_tmr); 428 429 data.flags |= SEV_INIT_FLAGS_SEV_ES; 430 data.tmr_len = SEV_ES_TMR_SIZE; 431 } 432 433 return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); 434 } 435 436 static int __sev_init_ex_locked(int *error) 437 { 438 struct sev_data_init_ex data; 439 440 memset(&data, 0, sizeof(data)); 441 data.length = sizeof(data); 442 data.nv_address = __psp_pa(sev_init_ex_buffer); 443 data.nv_len = NV_LENGTH; 444 445 if (sev_es_tmr) { 446 /* 447 * Do not include the encryption mask on the physical 448 * address of the TMR (firmware should clear it anyway). 449 */ 450 data.tmr_address = __pa(sev_es_tmr); 451 452 data.flags |= SEV_INIT_FLAGS_SEV_ES; 453 data.tmr_len = SEV_ES_TMR_SIZE; 454 } 455 456 return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); 457 } 458 459 static inline int __sev_do_init_locked(int *psp_ret) 460 { 461 if (sev_init_ex_buffer) 462 return __sev_init_ex_locked(psp_ret); 463 else 464 return __sev_init_locked(psp_ret); 465 } 466 467 static int __sev_platform_init_locked(int *error) 468 { 469 int rc = 0, psp_ret = SEV_RET_NO_FW_CALL; 470 struct psp_device *psp = psp_master; 471 struct sev_device *sev; 472 473 if (!psp || !psp->sev_data) 474 return -ENODEV; 475 476 sev = psp->sev_data; 477 478 if (sev->state == SEV_STATE_INIT) 479 return 0; 480 481 if (sev_init_ex_buffer) { 482 rc = sev_read_init_ex_file(); 483 if (rc) 484 return rc; 485 } 486 487 rc = __sev_do_init_locked(&psp_ret); 488 if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { 489 /* 490 * Initialization command returned an integrity check failure 491 * status code, meaning that firmware load and validation of SEV 492 * related persistent data has failed. Retrying the 493 * initialization function should succeed by replacing the state 494 * with a reset state. 495 */ 496 dev_err(sev->dev, 497 "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); 498 rc = __sev_do_init_locked(&psp_ret); 499 } 500 501 if (error) 502 *error = psp_ret; 503 504 if (rc) 505 return rc; 506 507 sev->state = SEV_STATE_INIT; 508 509 /* Prepare for first SEV guest launch after INIT */ 510 wbinvd_on_all_cpus(); 511 rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error); 512 if (rc) 513 return rc; 514 515 dev_dbg(sev->dev, "SEV firmware initialized\n"); 516 517 dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, 518 sev->api_minor, sev->build); 519 520 return 0; 521 } 522 523 int sev_platform_init(int *error) 524 { 525 int rc; 526 527 mutex_lock(&sev_cmd_mutex); 528 rc = __sev_platform_init_locked(error); 529 mutex_unlock(&sev_cmd_mutex); 530 531 return rc; 532 } 533 EXPORT_SYMBOL_GPL(sev_platform_init); 534 535 static int __sev_platform_shutdown_locked(int *error) 536 { 537 struct sev_device *sev = psp_master->sev_data; 538 int ret; 539 540 if (!sev || sev->state == SEV_STATE_UNINIT) 541 return 0; 542 543 ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); 544 if (ret) 545 return ret; 546 547 sev->state = SEV_STATE_UNINIT; 548 dev_dbg(sev->dev, "SEV firmware shutdown\n"); 549 550 return ret; 551 } 552 553 static int sev_platform_shutdown(int *error) 554 { 555 int rc; 556 557 mutex_lock(&sev_cmd_mutex); 558 rc = __sev_platform_shutdown_locked(NULL); 559 mutex_unlock(&sev_cmd_mutex); 560 561 return rc; 562 } 563 564 static int sev_get_platform_state(int *state, int *error) 565 { 566 struct sev_user_data_status data; 567 int rc; 568 569 rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); 570 if (rc) 571 return rc; 572 573 *state = data.state; 574 return rc; 575 } 576 577 static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) 578 { 579 int state, rc; 580 581 if (!writable) 582 return -EPERM; 583 584 /* 585 * The SEV spec requires that FACTORY_RESET must be issued in 586 * UNINIT state. Before we go further lets check if any guest is 587 * active. 588 * 589 * If FW is in WORKING state then deny the request otherwise issue 590 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. 591 * 592 */ 593 rc = sev_get_platform_state(&state, &argp->error); 594 if (rc) 595 return rc; 596 597 if (state == SEV_STATE_WORKING) 598 return -EBUSY; 599 600 if (state == SEV_STATE_INIT) { 601 rc = __sev_platform_shutdown_locked(&argp->error); 602 if (rc) 603 return rc; 604 } 605 606 return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); 607 } 608 609 static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) 610 { 611 struct sev_user_data_status data; 612 int ret; 613 614 memset(&data, 0, sizeof(data)); 615 616 ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); 617 if (ret) 618 return ret; 619 620 if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) 621 ret = -EFAULT; 622 623 return ret; 624 } 625 626 static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) 627 { 628 struct sev_device *sev = psp_master->sev_data; 629 int rc; 630 631 if (!writable) 632 return -EPERM; 633 634 if (sev->state == SEV_STATE_UNINIT) { 635 rc = __sev_platform_init_locked(&argp->error); 636 if (rc) 637 return rc; 638 } 639 640 return __sev_do_cmd_locked(cmd, NULL, &argp->error); 641 } 642 643 static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) 644 { 645 struct sev_device *sev = psp_master->sev_data; 646 struct sev_user_data_pek_csr input; 647 struct sev_data_pek_csr data; 648 void __user *input_address; 649 void *blob = NULL; 650 int ret; 651 652 if (!writable) 653 return -EPERM; 654 655 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 656 return -EFAULT; 657 658 memset(&data, 0, sizeof(data)); 659 660 /* userspace wants to query CSR length */ 661 if (!input.address || !input.length) 662 goto cmd; 663 664 /* allocate a physically contiguous buffer to store the CSR blob */ 665 input_address = (void __user *)input.address; 666 if (input.length > SEV_FW_BLOB_MAX_SIZE) 667 return -EFAULT; 668 669 blob = kzalloc(input.length, GFP_KERNEL); 670 if (!blob) 671 return -ENOMEM; 672 673 data.address = __psp_pa(blob); 674 data.len = input.length; 675 676 cmd: 677 if (sev->state == SEV_STATE_UNINIT) { 678 ret = __sev_platform_init_locked(&argp->error); 679 if (ret) 680 goto e_free_blob; 681 } 682 683 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); 684 685 /* If we query the CSR length, FW responded with expected data. */ 686 input.length = data.len; 687 688 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 689 ret = -EFAULT; 690 goto e_free_blob; 691 } 692 693 if (blob) { 694 if (copy_to_user(input_address, blob, input.length)) 695 ret = -EFAULT; 696 } 697 698 e_free_blob: 699 kfree(blob); 700 return ret; 701 } 702 703 void *psp_copy_user_blob(u64 uaddr, u32 len) 704 { 705 if (!uaddr || !len) 706 return ERR_PTR(-EINVAL); 707 708 /* verify that blob length does not exceed our limit */ 709 if (len > SEV_FW_BLOB_MAX_SIZE) 710 return ERR_PTR(-EINVAL); 711 712 return memdup_user((void __user *)uaddr, len); 713 } 714 EXPORT_SYMBOL_GPL(psp_copy_user_blob); 715 716 static int sev_get_api_version(void) 717 { 718 struct sev_device *sev = psp_master->sev_data; 719 struct sev_user_data_status status; 720 int error = 0, ret; 721 722 ret = sev_platform_status(&status, &error); 723 if (ret) { 724 dev_err(sev->dev, 725 "SEV: failed to get status. Error: %#x\n", error); 726 return 1; 727 } 728 729 sev->api_major = status.api_major; 730 sev->api_minor = status.api_minor; 731 sev->build = status.build; 732 sev->state = status.state; 733 734 return 0; 735 } 736 737 static int sev_get_firmware(struct device *dev, 738 const struct firmware **firmware) 739 { 740 char fw_name_specific[SEV_FW_NAME_SIZE]; 741 char fw_name_subset[SEV_FW_NAME_SIZE]; 742 743 snprintf(fw_name_specific, sizeof(fw_name_specific), 744 "amd/amd_sev_fam%.2xh_model%.2xh.sbin", 745 boot_cpu_data.x86, boot_cpu_data.x86_model); 746 747 snprintf(fw_name_subset, sizeof(fw_name_subset), 748 "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", 749 boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); 750 751 /* Check for SEV FW for a particular model. 752 * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h 753 * 754 * or 755 * 756 * Check for SEV FW common to a subset of models. 757 * Ex. amd_sev_fam17h_model0xh.sbin for 758 * Family 17h Model 00h -- Family 17h Model 0Fh 759 * 760 * or 761 * 762 * Fall-back to using generic name: sev.fw 763 */ 764 if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || 765 (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || 766 (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) 767 return 0; 768 769 return -ENOENT; 770 } 771 772 /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ 773 static int sev_update_firmware(struct device *dev) 774 { 775 struct sev_data_download_firmware *data; 776 const struct firmware *firmware; 777 int ret, error, order; 778 struct page *p; 779 u64 data_size; 780 781 if (!sev_version_greater_or_equal(0, 15)) { 782 dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); 783 return -1; 784 } 785 786 if (sev_get_firmware(dev, &firmware) == -ENOENT) { 787 dev_dbg(dev, "No SEV firmware file present\n"); 788 return -1; 789 } 790 791 /* 792 * SEV FW expects the physical address given to it to be 32 793 * byte aligned. Memory allocated has structure placed at the 794 * beginning followed by the firmware being passed to the SEV 795 * FW. Allocate enough memory for data structure + alignment 796 * padding + SEV FW. 797 */ 798 data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32); 799 800 order = get_order(firmware->size + data_size); 801 p = alloc_pages(GFP_KERNEL, order); 802 if (!p) { 803 ret = -1; 804 goto fw_err; 805 } 806 807 /* 808 * Copy firmware data to a kernel allocated contiguous 809 * memory region. 810 */ 811 data = page_address(p); 812 memcpy(page_address(p) + data_size, firmware->data, firmware->size); 813 814 data->address = __psp_pa(page_address(p) + data_size); 815 data->len = firmware->size; 816 817 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 818 819 /* 820 * A quirk for fixing the committed TCB version, when upgrading from 821 * earlier firmware version than 1.50. 822 */ 823 if (!ret && !sev_version_greater_or_equal(1, 50)) 824 ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); 825 826 if (ret) 827 dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); 828 else 829 dev_info(dev, "SEV firmware update successful\n"); 830 831 __free_pages(p, order); 832 833 fw_err: 834 release_firmware(firmware); 835 836 return ret; 837 } 838 839 static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) 840 { 841 struct sev_device *sev = psp_master->sev_data; 842 struct sev_user_data_pek_cert_import input; 843 struct sev_data_pek_cert_import data; 844 void *pek_blob, *oca_blob; 845 int ret; 846 847 if (!writable) 848 return -EPERM; 849 850 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 851 return -EFAULT; 852 853 /* copy PEK certificate blobs from userspace */ 854 pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); 855 if (IS_ERR(pek_blob)) 856 return PTR_ERR(pek_blob); 857 858 data.reserved = 0; 859 data.pek_cert_address = __psp_pa(pek_blob); 860 data.pek_cert_len = input.pek_cert_len; 861 862 /* copy PEK certificate blobs from userspace */ 863 oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); 864 if (IS_ERR(oca_blob)) { 865 ret = PTR_ERR(oca_blob); 866 goto e_free_pek; 867 } 868 869 data.oca_cert_address = __psp_pa(oca_blob); 870 data.oca_cert_len = input.oca_cert_len; 871 872 /* If platform is not in INIT state then transition it to INIT */ 873 if (sev->state != SEV_STATE_INIT) { 874 ret = __sev_platform_init_locked(&argp->error); 875 if (ret) 876 goto e_free_oca; 877 } 878 879 ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); 880 881 e_free_oca: 882 kfree(oca_blob); 883 e_free_pek: 884 kfree(pek_blob); 885 return ret; 886 } 887 888 static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) 889 { 890 struct sev_user_data_get_id2 input; 891 struct sev_data_get_id data; 892 void __user *input_address; 893 void *id_blob = NULL; 894 int ret; 895 896 /* SEV GET_ID is available from SEV API v0.16 and up */ 897 if (!sev_version_greater_or_equal(0, 16)) 898 return -ENOTSUPP; 899 900 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 901 return -EFAULT; 902 903 input_address = (void __user *)input.address; 904 905 if (input.address && input.length) { 906 /* 907 * The length of the ID shouldn't be assumed by software since 908 * it may change in the future. The allocation size is limited 909 * to 1 << (PAGE_SHIFT + MAX_ORDER) by the page allocator. 910 * If the allocation fails, simply return ENOMEM rather than 911 * warning in the kernel log. 912 */ 913 id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); 914 if (!id_blob) 915 return -ENOMEM; 916 917 data.address = __psp_pa(id_blob); 918 data.len = input.length; 919 } else { 920 data.address = 0; 921 data.len = 0; 922 } 923 924 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); 925 926 /* 927 * Firmware will return the length of the ID value (either the minimum 928 * required length or the actual length written), return it to the user. 929 */ 930 input.length = data.len; 931 932 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 933 ret = -EFAULT; 934 goto e_free; 935 } 936 937 if (id_blob) { 938 if (copy_to_user(input_address, id_blob, data.len)) { 939 ret = -EFAULT; 940 goto e_free; 941 } 942 } 943 944 e_free: 945 kfree(id_blob); 946 947 return ret; 948 } 949 950 static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) 951 { 952 struct sev_data_get_id *data; 953 u64 data_size, user_size; 954 void *id_blob, *mem; 955 int ret; 956 957 /* SEV GET_ID available from SEV API v0.16 and up */ 958 if (!sev_version_greater_or_equal(0, 16)) 959 return -ENOTSUPP; 960 961 /* SEV FW expects the buffer it fills with the ID to be 962 * 8-byte aligned. Memory allocated should be enough to 963 * hold data structure + alignment padding + memory 964 * where SEV FW writes the ID. 965 */ 966 data_size = ALIGN(sizeof(struct sev_data_get_id), 8); 967 user_size = sizeof(struct sev_user_data_get_id); 968 969 mem = kzalloc(data_size + user_size, GFP_KERNEL); 970 if (!mem) 971 return -ENOMEM; 972 973 data = mem; 974 id_blob = mem + data_size; 975 976 data->address = __psp_pa(id_blob); 977 data->len = user_size; 978 979 ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); 980 if (!ret) { 981 if (copy_to_user((void __user *)argp->data, id_blob, data->len)) 982 ret = -EFAULT; 983 } 984 985 kfree(mem); 986 987 return ret; 988 } 989 990 static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) 991 { 992 struct sev_device *sev = psp_master->sev_data; 993 struct sev_user_data_pdh_cert_export input; 994 void *pdh_blob = NULL, *cert_blob = NULL; 995 struct sev_data_pdh_cert_export data; 996 void __user *input_cert_chain_address; 997 void __user *input_pdh_cert_address; 998 int ret; 999 1000 /* If platform is not in INIT state then transition it to INIT. */ 1001 if (sev->state != SEV_STATE_INIT) { 1002 if (!writable) 1003 return -EPERM; 1004 1005 ret = __sev_platform_init_locked(&argp->error); 1006 if (ret) 1007 return ret; 1008 } 1009 1010 if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) 1011 return -EFAULT; 1012 1013 memset(&data, 0, sizeof(data)); 1014 1015 /* Userspace wants to query the certificate length. */ 1016 if (!input.pdh_cert_address || 1017 !input.pdh_cert_len || 1018 !input.cert_chain_address) 1019 goto cmd; 1020 1021 input_pdh_cert_address = (void __user *)input.pdh_cert_address; 1022 input_cert_chain_address = (void __user *)input.cert_chain_address; 1023 1024 /* Allocate a physically contiguous buffer to store the PDH blob. */ 1025 if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) 1026 return -EFAULT; 1027 1028 /* Allocate a physically contiguous buffer to store the cert chain blob. */ 1029 if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) 1030 return -EFAULT; 1031 1032 pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); 1033 if (!pdh_blob) 1034 return -ENOMEM; 1035 1036 data.pdh_cert_address = __psp_pa(pdh_blob); 1037 data.pdh_cert_len = input.pdh_cert_len; 1038 1039 cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); 1040 if (!cert_blob) { 1041 ret = -ENOMEM; 1042 goto e_free_pdh; 1043 } 1044 1045 data.cert_chain_address = __psp_pa(cert_blob); 1046 data.cert_chain_len = input.cert_chain_len; 1047 1048 cmd: 1049 ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); 1050 1051 /* If we query the length, FW responded with expected data. */ 1052 input.cert_chain_len = data.cert_chain_len; 1053 input.pdh_cert_len = data.pdh_cert_len; 1054 1055 if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { 1056 ret = -EFAULT; 1057 goto e_free_cert; 1058 } 1059 1060 if (pdh_blob) { 1061 if (copy_to_user(input_pdh_cert_address, 1062 pdh_blob, input.pdh_cert_len)) { 1063 ret = -EFAULT; 1064 goto e_free_cert; 1065 } 1066 } 1067 1068 if (cert_blob) { 1069 if (copy_to_user(input_cert_chain_address, 1070 cert_blob, input.cert_chain_len)) 1071 ret = -EFAULT; 1072 } 1073 1074 e_free_cert: 1075 kfree(cert_blob); 1076 e_free_pdh: 1077 kfree(pdh_blob); 1078 return ret; 1079 } 1080 1081 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) 1082 { 1083 void __user *argp = (void __user *)arg; 1084 struct sev_issue_cmd input; 1085 int ret = -EFAULT; 1086 bool writable = file->f_mode & FMODE_WRITE; 1087 1088 if (!psp_master || !psp_master->sev_data) 1089 return -ENODEV; 1090 1091 if (ioctl != SEV_ISSUE_CMD) 1092 return -EINVAL; 1093 1094 if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) 1095 return -EFAULT; 1096 1097 if (input.cmd > SEV_MAX) 1098 return -EINVAL; 1099 1100 mutex_lock(&sev_cmd_mutex); 1101 1102 switch (input.cmd) { 1103 1104 case SEV_FACTORY_RESET: 1105 ret = sev_ioctl_do_reset(&input, writable); 1106 break; 1107 case SEV_PLATFORM_STATUS: 1108 ret = sev_ioctl_do_platform_status(&input); 1109 break; 1110 case SEV_PEK_GEN: 1111 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); 1112 break; 1113 case SEV_PDH_GEN: 1114 ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); 1115 break; 1116 case SEV_PEK_CSR: 1117 ret = sev_ioctl_do_pek_csr(&input, writable); 1118 break; 1119 case SEV_PEK_CERT_IMPORT: 1120 ret = sev_ioctl_do_pek_import(&input, writable); 1121 break; 1122 case SEV_PDH_CERT_EXPORT: 1123 ret = sev_ioctl_do_pdh_export(&input, writable); 1124 break; 1125 case SEV_GET_ID: 1126 pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); 1127 ret = sev_ioctl_do_get_id(&input); 1128 break; 1129 case SEV_GET_ID2: 1130 ret = sev_ioctl_do_get_id2(&input); 1131 break; 1132 default: 1133 ret = -EINVAL; 1134 goto out; 1135 } 1136 1137 if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) 1138 ret = -EFAULT; 1139 out: 1140 mutex_unlock(&sev_cmd_mutex); 1141 1142 return ret; 1143 } 1144 1145 static const struct file_operations sev_fops = { 1146 .owner = THIS_MODULE, 1147 .unlocked_ioctl = sev_ioctl, 1148 }; 1149 1150 int sev_platform_status(struct sev_user_data_status *data, int *error) 1151 { 1152 return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); 1153 } 1154 EXPORT_SYMBOL_GPL(sev_platform_status); 1155 1156 int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) 1157 { 1158 return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); 1159 } 1160 EXPORT_SYMBOL_GPL(sev_guest_deactivate); 1161 1162 int sev_guest_activate(struct sev_data_activate *data, int *error) 1163 { 1164 return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); 1165 } 1166 EXPORT_SYMBOL_GPL(sev_guest_activate); 1167 1168 int sev_guest_decommission(struct sev_data_decommission *data, int *error) 1169 { 1170 return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); 1171 } 1172 EXPORT_SYMBOL_GPL(sev_guest_decommission); 1173 1174 int sev_guest_df_flush(int *error) 1175 { 1176 return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); 1177 } 1178 EXPORT_SYMBOL_GPL(sev_guest_df_flush); 1179 1180 static void sev_exit(struct kref *ref) 1181 { 1182 misc_deregister(&misc_dev->misc); 1183 kfree(misc_dev); 1184 misc_dev = NULL; 1185 } 1186 1187 static int sev_misc_init(struct sev_device *sev) 1188 { 1189 struct device *dev = sev->dev; 1190 int ret; 1191 1192 /* 1193 * SEV feature support can be detected on multiple devices but the SEV 1194 * FW commands must be issued on the master. During probe, we do not 1195 * know the master hence we create /dev/sev on the first device probe. 1196 * sev_do_cmd() finds the right master device to which to issue the 1197 * command to the firmware. 1198 */ 1199 if (!misc_dev) { 1200 struct miscdevice *misc; 1201 1202 misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL); 1203 if (!misc_dev) 1204 return -ENOMEM; 1205 1206 misc = &misc_dev->misc; 1207 misc->minor = MISC_DYNAMIC_MINOR; 1208 misc->name = DEVICE_NAME; 1209 misc->fops = &sev_fops; 1210 1211 ret = misc_register(misc); 1212 if (ret) 1213 return ret; 1214 1215 kref_init(&misc_dev->refcount); 1216 } else { 1217 kref_get(&misc_dev->refcount); 1218 } 1219 1220 init_waitqueue_head(&sev->int_queue); 1221 sev->misc = misc_dev; 1222 dev_dbg(dev, "registered SEV device\n"); 1223 1224 return 0; 1225 } 1226 1227 int sev_dev_init(struct psp_device *psp) 1228 { 1229 struct device *dev = psp->dev; 1230 struct sev_device *sev; 1231 int ret = -ENOMEM; 1232 1233 if (!boot_cpu_has(X86_FEATURE_SEV)) { 1234 dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); 1235 return 0; 1236 } 1237 1238 sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); 1239 if (!sev) 1240 goto e_err; 1241 1242 sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0); 1243 if (!sev->cmd_buf) 1244 goto e_sev; 1245 1246 psp->sev_data = sev; 1247 1248 sev->dev = dev; 1249 sev->psp = psp; 1250 1251 sev->io_regs = psp->io_regs; 1252 1253 sev->vdata = (struct sev_vdata *)psp->vdata->sev; 1254 if (!sev->vdata) { 1255 ret = -ENODEV; 1256 dev_err(dev, "sev: missing driver data\n"); 1257 goto e_buf; 1258 } 1259 1260 psp_set_sev_irq_handler(psp, sev_irq_handler, sev); 1261 1262 ret = sev_misc_init(sev); 1263 if (ret) 1264 goto e_irq; 1265 1266 dev_notice(dev, "sev enabled\n"); 1267 1268 return 0; 1269 1270 e_irq: 1271 psp_clear_sev_irq_handler(psp); 1272 e_buf: 1273 devm_free_pages(dev, (unsigned long)sev->cmd_buf); 1274 e_sev: 1275 devm_kfree(dev, sev); 1276 e_err: 1277 psp->sev_data = NULL; 1278 1279 dev_notice(dev, "sev initialization failed\n"); 1280 1281 return ret; 1282 } 1283 1284 static void sev_firmware_shutdown(struct sev_device *sev) 1285 { 1286 sev_platform_shutdown(NULL); 1287 1288 if (sev_es_tmr) { 1289 /* The TMR area was encrypted, flush it from the cache */ 1290 wbinvd_on_all_cpus(); 1291 1292 free_pages((unsigned long)sev_es_tmr, 1293 get_order(SEV_ES_TMR_SIZE)); 1294 sev_es_tmr = NULL; 1295 } 1296 1297 if (sev_init_ex_buffer) { 1298 free_pages((unsigned long)sev_init_ex_buffer, 1299 get_order(NV_LENGTH)); 1300 sev_init_ex_buffer = NULL; 1301 } 1302 } 1303 1304 void sev_dev_destroy(struct psp_device *psp) 1305 { 1306 struct sev_device *sev = psp->sev_data; 1307 1308 if (!sev) 1309 return; 1310 1311 sev_firmware_shutdown(sev); 1312 1313 if (sev->misc) 1314 kref_put(&misc_dev->refcount, sev_exit); 1315 1316 psp_clear_sev_irq_handler(psp); 1317 } 1318 1319 int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, 1320 void *data, int *error) 1321 { 1322 if (!filep || filep->f_op != &sev_fops) 1323 return -EBADF; 1324 1325 return sev_do_cmd(cmd, data, error); 1326 } 1327 EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); 1328 1329 void sev_pci_init(void) 1330 { 1331 struct sev_device *sev = psp_master->sev_data; 1332 int error, rc; 1333 1334 if (!sev) 1335 return; 1336 1337 psp_timeout = psp_probe_timeout; 1338 1339 if (sev_get_api_version()) 1340 goto err; 1341 1342 if (sev_update_firmware(sev->dev) == 0) 1343 sev_get_api_version(); 1344 1345 /* If an init_ex_path is provided rely on INIT_EX for PSP initialization 1346 * instead of INIT. 1347 */ 1348 if (init_ex_path) { 1349 sev_init_ex_buffer = sev_fw_alloc(NV_LENGTH); 1350 if (!sev_init_ex_buffer) { 1351 dev_err(sev->dev, 1352 "SEV: INIT_EX NV memory allocation failed\n"); 1353 goto err; 1354 } 1355 } 1356 1357 /* Obtain the TMR memory area for SEV-ES use */ 1358 sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE); 1359 if (sev_es_tmr) 1360 /* Must flush the cache before giving it to the firmware */ 1361 clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE); 1362 else 1363 dev_warn(sev->dev, 1364 "SEV: TMR allocation failed, SEV-ES support unavailable\n"); 1365 1366 if (!psp_init_on_probe) 1367 return; 1368 1369 /* Initialize the platform */ 1370 rc = sev_platform_init(&error); 1371 if (rc) 1372 dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n", 1373 error, rc); 1374 1375 return; 1376 1377 err: 1378 psp_master->sev_data = NULL; 1379 } 1380 1381 void sev_pci_exit(void) 1382 { 1383 struct sev_device *sev = psp_master->sev_data; 1384 1385 if (!sev) 1386 return; 1387 1388 sev_firmware_shutdown(sev); 1389 } 1390