// SPDX-License-Identifier: GPL-2.0-only /* * AMD Secure Encrypted Virtualization (SEV) interface * * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. * * Author: Brijesh Singh */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "psp-dev.h" #include "sev-dev.h" #define DEVICE_NAME "sev" #define SEV_FW_FILE "amd/sev.fw" #define SEV_FW_NAME_SIZE 64 static DEFINE_MUTEX(sev_cmd_mutex); static struct sev_misc_dev *misc_dev; static int psp_cmd_timeout = 100; module_param(psp_cmd_timeout, int, 0644); MODULE_PARM_DESC(psp_cmd_timeout, " default timeout value, in seconds, for PSP commands"); static int psp_probe_timeout = 5; module_param(psp_probe_timeout, int, 0644); MODULE_PARM_DESC(psp_probe_timeout, " default timeout value, in seconds, during PSP device probe"); static char *init_ex_path; module_param(init_ex_path, charp, 0444); MODULE_PARM_DESC(init_ex_path, " Path for INIT_EX data; if set try INIT_EX"); static bool psp_init_on_probe = true; module_param(psp_init_on_probe, bool, 0444); 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"); MODULE_FIRMWARE("amd/amd_sev_fam17h_model0xh.sbin"); /* 1st gen EPYC */ MODULE_FIRMWARE("amd/amd_sev_fam17h_model3xh.sbin"); /* 2nd gen EPYC */ MODULE_FIRMWARE("amd/amd_sev_fam19h_model0xh.sbin"); /* 3rd gen EPYC */ static bool psp_dead; static int psp_timeout; /* Trusted Memory Region (TMR): * The TMR is a 1MB area that must be 1MB aligned. Use the page allocator * to allocate the memory, which will return aligned memory for the specified * allocation order. */ #define SEV_ES_TMR_SIZE (1024 * 1024) static void *sev_es_tmr; /* INIT_EX NV Storage: * The NV Storage is a 32Kb area and must be 4Kb page aligned. Use the page * allocator to allocate the memory, which will return aligned memory for the * specified allocation order. */ #define NV_LENGTH (32 * 1024) static void *sev_init_ex_buffer; static inline bool sev_version_greater_or_equal(u8 maj, u8 min) { struct sev_device *sev = psp_master->sev_data; if (sev->api_major > maj) return true; if (sev->api_major == maj && sev->api_minor >= min) return true; return false; } static void sev_irq_handler(int irq, void *data, unsigned int status) { struct sev_device *sev = data; int reg; /* Check if it is command completion: */ if (!(status & SEV_CMD_COMPLETE)) return; /* Check if it is SEV command completion: */ reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); if (reg & PSP_CMDRESP_RESP) { sev->int_rcvd = 1; wake_up(&sev->int_queue); } } static int sev_wait_cmd_ioc(struct sev_device *sev, unsigned int *reg, unsigned int timeout) { int ret; ret = wait_event_timeout(sev->int_queue, sev->int_rcvd, timeout * HZ); if (!ret) return -ETIMEDOUT; *reg = ioread32(sev->io_regs + sev->vdata->cmdresp_reg); return 0; } static int sev_cmd_buffer_len(int cmd) { switch (cmd) { case SEV_CMD_INIT: return sizeof(struct sev_data_init); case SEV_CMD_INIT_EX: return sizeof(struct sev_data_init_ex); case SEV_CMD_PLATFORM_STATUS: return sizeof(struct sev_user_data_status); case SEV_CMD_PEK_CSR: return sizeof(struct sev_data_pek_csr); case SEV_CMD_PEK_CERT_IMPORT: return sizeof(struct sev_data_pek_cert_import); case SEV_CMD_PDH_CERT_EXPORT: return sizeof(struct sev_data_pdh_cert_export); case SEV_CMD_LAUNCH_START: return sizeof(struct sev_data_launch_start); case SEV_CMD_LAUNCH_UPDATE_DATA: return sizeof(struct sev_data_launch_update_data); case SEV_CMD_LAUNCH_UPDATE_VMSA: return sizeof(struct sev_data_launch_update_vmsa); case SEV_CMD_LAUNCH_FINISH: return sizeof(struct sev_data_launch_finish); case SEV_CMD_LAUNCH_MEASURE: return sizeof(struct sev_data_launch_measure); case SEV_CMD_ACTIVATE: return sizeof(struct sev_data_activate); case SEV_CMD_DEACTIVATE: return sizeof(struct sev_data_deactivate); case SEV_CMD_DECOMMISSION: return sizeof(struct sev_data_decommission); case SEV_CMD_GUEST_STATUS: return sizeof(struct sev_data_guest_status); case SEV_CMD_DBG_DECRYPT: return sizeof(struct sev_data_dbg); case SEV_CMD_DBG_ENCRYPT: return sizeof(struct sev_data_dbg); case SEV_CMD_SEND_START: return sizeof(struct sev_data_send_start); case SEV_CMD_SEND_UPDATE_DATA: return sizeof(struct sev_data_send_update_data); case SEV_CMD_SEND_UPDATE_VMSA: return sizeof(struct sev_data_send_update_vmsa); case SEV_CMD_SEND_FINISH: return sizeof(struct sev_data_send_finish); case SEV_CMD_RECEIVE_START: return sizeof(struct sev_data_receive_start); case SEV_CMD_RECEIVE_FINISH: return sizeof(struct sev_data_receive_finish); case SEV_CMD_RECEIVE_UPDATE_DATA: return sizeof(struct sev_data_receive_update_data); case SEV_CMD_RECEIVE_UPDATE_VMSA: return sizeof(struct sev_data_receive_update_vmsa); case SEV_CMD_LAUNCH_UPDATE_SECRET: return sizeof(struct sev_data_launch_secret); case SEV_CMD_DOWNLOAD_FIRMWARE: return sizeof(struct sev_data_download_firmware); case SEV_CMD_GET_ID: return sizeof(struct sev_data_get_id); case SEV_CMD_ATTESTATION_REPORT: return sizeof(struct sev_data_attestation_report); case SEV_CMD_SEND_CANCEL: return sizeof(struct sev_data_send_cancel); default: return 0; } return 0; } static void *sev_fw_alloc(unsigned long len) { struct page *page; page = alloc_pages(GFP_KERNEL, get_order(len)); if (!page) return NULL; return page_address(page); } static struct file *open_file_as_root(const char *filename, int flags, umode_t mode) { struct file *fp; struct path root; struct cred *cred; const struct cred *old_cred; task_lock(&init_task); get_fs_root(init_task.fs, &root); task_unlock(&init_task); cred = prepare_creds(); if (!cred) return ERR_PTR(-ENOMEM); cred->fsuid = GLOBAL_ROOT_UID; old_cred = override_creds(cred); fp = file_open_root(&root, filename, flags, mode); path_put(&root); revert_creds(old_cred); return fp; } static int sev_read_init_ex_file(void) { struct sev_device *sev = psp_master->sev_data; struct file *fp; ssize_t nread; lockdep_assert_held(&sev_cmd_mutex); if (!sev_init_ex_buffer) return -EOPNOTSUPP; fp = open_file_as_root(init_ex_path, O_RDONLY, 0); if (IS_ERR(fp)) { int ret = PTR_ERR(fp); if (ret == -ENOENT) { dev_info(sev->dev, "SEV: %s does not exist and will be created later.\n", init_ex_path); ret = 0; } else { dev_err(sev->dev, "SEV: could not open %s for read, error %d\n", init_ex_path, ret); } return ret; } nread = kernel_read(fp, sev_init_ex_buffer, NV_LENGTH, NULL); if (nread != NV_LENGTH) { dev_info(sev->dev, "SEV: could not read %u bytes to non volatile memory area, ret %ld\n", NV_LENGTH, nread); } dev_dbg(sev->dev, "SEV: read %ld bytes from NV file\n", nread); filp_close(fp, NULL); return 0; } static int sev_write_init_ex_file(void) { struct sev_device *sev = psp_master->sev_data; struct file *fp; loff_t offset = 0; ssize_t nwrite; lockdep_assert_held(&sev_cmd_mutex); if (!sev_init_ex_buffer) return 0; fp = open_file_as_root(init_ex_path, O_CREAT | O_WRONLY, 0600); if (IS_ERR(fp)) { int ret = PTR_ERR(fp); dev_err(sev->dev, "SEV: could not open file for write, error %d\n", ret); return ret; } nwrite = kernel_write(fp, sev_init_ex_buffer, NV_LENGTH, &offset); vfs_fsync(fp, 0); filp_close(fp, NULL); if (nwrite != NV_LENGTH) { dev_err(sev->dev, "SEV: failed to write %u bytes to non volatile memory area, ret %ld\n", NV_LENGTH, nwrite); return -EIO; } dev_dbg(sev->dev, "SEV: write successful to NV file\n"); return 0; } static int sev_write_init_ex_file_if_required(int cmd_id) { lockdep_assert_held(&sev_cmd_mutex); if (!sev_init_ex_buffer) return 0; /* * Only a few platform commands modify the SPI/NV area, but none of the * non-platform commands do. Only INIT(_EX), PLATFORM_RESET, PEK_GEN, * PEK_CERT_IMPORT, and PDH_GEN do. */ switch (cmd_id) { case SEV_CMD_FACTORY_RESET: case SEV_CMD_INIT_EX: case SEV_CMD_PDH_GEN: case SEV_CMD_PEK_CERT_IMPORT: case SEV_CMD_PEK_GEN: break; default: return 0; } return sev_write_init_ex_file(); } static int __sev_do_cmd_locked(int cmd, void *data, int *psp_ret) { struct psp_device *psp = psp_master; struct sev_device *sev; unsigned int phys_lsb, phys_msb; unsigned int reg, ret = 0; int buf_len; if (!psp || !psp->sev_data) return -ENODEV; if (psp_dead) return -EBUSY; sev = psp->sev_data; buf_len = sev_cmd_buffer_len(cmd); if (WARN_ON_ONCE(!data != !buf_len)) return -EINVAL; /* * Copy the incoming data to driver's scratch buffer as __pa() will not * work for some memory, e.g. vmalloc'd addresses, and @data may not be * physically contiguous. */ if (data) memcpy(sev->cmd_buf, data, buf_len); /* Get the physical address of the command buffer */ phys_lsb = data ? lower_32_bits(__psp_pa(sev->cmd_buf)) : 0; phys_msb = data ? upper_32_bits(__psp_pa(sev->cmd_buf)) : 0; dev_dbg(sev->dev, "sev command id %#x buffer 0x%08x%08x timeout %us\n", cmd, phys_msb, phys_lsb, psp_timeout); print_hex_dump_debug("(in): ", DUMP_PREFIX_OFFSET, 16, 2, data, buf_len, false); iowrite32(phys_lsb, sev->io_regs + sev->vdata->cmdbuff_addr_lo_reg); iowrite32(phys_msb, sev->io_regs + sev->vdata->cmdbuff_addr_hi_reg); sev->int_rcvd = 0; reg = cmd; reg <<= SEV_CMDRESP_CMD_SHIFT; reg |= SEV_CMDRESP_IOC; iowrite32(reg, sev->io_regs + sev->vdata->cmdresp_reg); /* wait for command completion */ ret = sev_wait_cmd_ioc(sev, ®, psp_timeout); if (ret) { if (psp_ret) *psp_ret = 0; dev_err(sev->dev, "sev command %#x timed out, disabling PSP\n", cmd); psp_dead = true; return ret; } psp_timeout = psp_cmd_timeout; if (psp_ret) *psp_ret = reg & PSP_CMDRESP_ERR_MASK; if (reg & PSP_CMDRESP_ERR_MASK) { dev_dbg(sev->dev, "sev command %#x failed (%#010x)\n", cmd, reg & PSP_CMDRESP_ERR_MASK); ret = -EIO; } else { ret = sev_write_init_ex_file_if_required(cmd); } print_hex_dump_debug("(out): ", DUMP_PREFIX_OFFSET, 16, 2, data, buf_len, false); /* * Copy potential output from the PSP back to data. Do this even on * failure in case the caller wants to glean something from the error. */ if (data) memcpy(data, sev->cmd_buf, buf_len); return ret; } static int sev_do_cmd(int cmd, void *data, int *psp_ret) { int rc; mutex_lock(&sev_cmd_mutex); rc = __sev_do_cmd_locked(cmd, data, psp_ret); mutex_unlock(&sev_cmd_mutex); return rc; } static int __sev_init_locked(int *error) { struct sev_data_init data; memset(&data, 0, sizeof(data)); if (sev_es_tmr) { /* * Do not include the encryption mask on the physical * address of the TMR (firmware should clear it anyway). */ data.tmr_address = __pa(sev_es_tmr); data.flags |= SEV_INIT_FLAGS_SEV_ES; data.tmr_len = SEV_ES_TMR_SIZE; } return __sev_do_cmd_locked(SEV_CMD_INIT, &data, error); } static int __sev_init_ex_locked(int *error) { struct sev_data_init_ex data; memset(&data, 0, sizeof(data)); data.length = sizeof(data); data.nv_address = __psp_pa(sev_init_ex_buffer); data.nv_len = NV_LENGTH; if (sev_es_tmr) { /* * Do not include the encryption mask on the physical * address of the TMR (firmware should clear it anyway). */ data.tmr_address = __pa(sev_es_tmr); data.flags |= SEV_INIT_FLAGS_SEV_ES; data.tmr_len = SEV_ES_TMR_SIZE; } return __sev_do_cmd_locked(SEV_CMD_INIT_EX, &data, error); } static int __sev_platform_init_locked(int *error) { struct psp_device *psp = psp_master; struct sev_device *sev; int rc = 0, psp_ret = -1; int (*init_function)(int *error); if (!psp || !psp->sev_data) return -ENODEV; sev = psp->sev_data; if (sev->state == SEV_STATE_INIT) return 0; if (sev_init_ex_buffer) { init_function = __sev_init_ex_locked; rc = sev_read_init_ex_file(); if (rc) return rc; } else { init_function = __sev_init_locked; } rc = init_function(&psp_ret); if (rc && psp_ret == SEV_RET_SECURE_DATA_INVALID) { /* * Initialization command returned an integrity check failure * status code, meaning that firmware load and validation of SEV * related persistent data has failed. Retrying the * initialization function should succeed by replacing the state * with a reset state. */ dev_err(sev->dev, "SEV: retrying INIT command because of SECURE_DATA_INVALID error. Retrying once to reset PSP SEV state."); rc = init_function(&psp_ret); } if (error) *error = psp_ret; if (rc) return rc; sev->state = SEV_STATE_INIT; /* Prepare for first SEV guest launch after INIT */ wbinvd_on_all_cpus(); rc = __sev_do_cmd_locked(SEV_CMD_DF_FLUSH, NULL, error); if (rc) return rc; dev_dbg(sev->dev, "SEV firmware initialized\n"); dev_info(sev->dev, "SEV API:%d.%d build:%d\n", sev->api_major, sev->api_minor, sev->build); return 0; } int sev_platform_init(int *error) { int rc; mutex_lock(&sev_cmd_mutex); rc = __sev_platform_init_locked(error); mutex_unlock(&sev_cmd_mutex); return rc; } EXPORT_SYMBOL_GPL(sev_platform_init); static int __sev_platform_shutdown_locked(int *error) { struct sev_device *sev = psp_master->sev_data; int ret; if (!sev || sev->state == SEV_STATE_UNINIT) return 0; ret = __sev_do_cmd_locked(SEV_CMD_SHUTDOWN, NULL, error); if (ret) return ret; sev->state = SEV_STATE_UNINIT; dev_dbg(sev->dev, "SEV firmware shutdown\n"); return ret; } static int sev_platform_shutdown(int *error) { int rc; mutex_lock(&sev_cmd_mutex); rc = __sev_platform_shutdown_locked(NULL); mutex_unlock(&sev_cmd_mutex); return rc; } static int sev_get_platform_state(int *state, int *error) { struct sev_user_data_status data; int rc; rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, error); if (rc) return rc; *state = data.state; return rc; } static int sev_ioctl_do_reset(struct sev_issue_cmd *argp, bool writable) { int state, rc; if (!writable) return -EPERM; /* * The SEV spec requires that FACTORY_RESET must be issued in * UNINIT state. Before we go further lets check if any guest is * active. * * If FW is in WORKING state then deny the request otherwise issue * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET. * */ rc = sev_get_platform_state(&state, &argp->error); if (rc) return rc; if (state == SEV_STATE_WORKING) return -EBUSY; if (state == SEV_STATE_INIT) { rc = __sev_platform_shutdown_locked(&argp->error); if (rc) return rc; } return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, NULL, &argp->error); } static int sev_ioctl_do_platform_status(struct sev_issue_cmd *argp) { struct sev_user_data_status data; int ret; memset(&data, 0, sizeof(data)); ret = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS, &data, &argp->error); if (ret) return ret; if (copy_to_user((void __user *)argp->data, &data, sizeof(data))) ret = -EFAULT; return ret; } static int sev_ioctl_do_pek_pdh_gen(int cmd, struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; int rc; if (!writable) return -EPERM; if (sev->state == SEV_STATE_UNINIT) { rc = __sev_platform_init_locked(&argp->error); if (rc) return rc; } return __sev_do_cmd_locked(cmd, NULL, &argp->error); } static int sev_ioctl_do_pek_csr(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_pek_csr input; struct sev_data_pek_csr data; void __user *input_address; void *blob = NULL; int ret; if (!writable) return -EPERM; if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; memset(&data, 0, sizeof(data)); /* userspace wants to query CSR length */ if (!input.address || !input.length) goto cmd; /* allocate a physically contiguous buffer to store the CSR blob */ input_address = (void __user *)input.address; if (input.length > SEV_FW_BLOB_MAX_SIZE) return -EFAULT; blob = kzalloc(input.length, GFP_KERNEL); if (!blob) return -ENOMEM; data.address = __psp_pa(blob); data.len = input.length; cmd: if (sev->state == SEV_STATE_UNINIT) { ret = __sev_platform_init_locked(&argp->error); if (ret) goto e_free_blob; } ret = __sev_do_cmd_locked(SEV_CMD_PEK_CSR, &data, &argp->error); /* If we query the CSR length, FW responded with expected data. */ input.length = data.len; if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { ret = -EFAULT; goto e_free_blob; } if (blob) { if (copy_to_user(input_address, blob, input.length)) ret = -EFAULT; } e_free_blob: kfree(blob); return ret; } void *psp_copy_user_blob(u64 uaddr, u32 len) { if (!uaddr || !len) return ERR_PTR(-EINVAL); /* verify that blob length does not exceed our limit */ if (len > SEV_FW_BLOB_MAX_SIZE) return ERR_PTR(-EINVAL); return memdup_user((void __user *)uaddr, len); } EXPORT_SYMBOL_GPL(psp_copy_user_blob); static int sev_get_api_version(void) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_status status; int error = 0, ret; ret = sev_platform_status(&status, &error); if (ret) { dev_err(sev->dev, "SEV: failed to get status. Error: %#x\n", error); return 1; } sev->api_major = status.api_major; sev->api_minor = status.api_minor; sev->build = status.build; sev->state = status.state; return 0; } static int sev_get_firmware(struct device *dev, const struct firmware **firmware) { char fw_name_specific[SEV_FW_NAME_SIZE]; char fw_name_subset[SEV_FW_NAME_SIZE]; snprintf(fw_name_specific, sizeof(fw_name_specific), "amd/amd_sev_fam%.2xh_model%.2xh.sbin", boot_cpu_data.x86, boot_cpu_data.x86_model); snprintf(fw_name_subset, sizeof(fw_name_subset), "amd/amd_sev_fam%.2xh_model%.1xxh.sbin", boot_cpu_data.x86, (boot_cpu_data.x86_model & 0xf0) >> 4); /* Check for SEV FW for a particular model. * Ex. amd_sev_fam17h_model00h.sbin for Family 17h Model 00h * * or * * Check for SEV FW common to a subset of models. * Ex. amd_sev_fam17h_model0xh.sbin for * Family 17h Model 00h -- Family 17h Model 0Fh * * or * * Fall-back to using generic name: sev.fw */ if ((firmware_request_nowarn(firmware, fw_name_specific, dev) >= 0) || (firmware_request_nowarn(firmware, fw_name_subset, dev) >= 0) || (firmware_request_nowarn(firmware, SEV_FW_FILE, dev) >= 0)) return 0; return -ENOENT; } /* Don't fail if SEV FW couldn't be updated. Continue with existing SEV FW */ static int sev_update_firmware(struct device *dev) { struct sev_data_download_firmware *data; const struct firmware *firmware; int ret, error, order; struct page *p; u64 data_size; if (!sev_version_greater_or_equal(0, 15)) { dev_dbg(dev, "DOWNLOAD_FIRMWARE not supported\n"); return -1; } if (sev_get_firmware(dev, &firmware) == -ENOENT) { dev_dbg(dev, "No SEV firmware file present\n"); return -1; } /* * SEV FW expects the physical address given to it to be 32 * byte aligned. Memory allocated has structure placed at the * beginning followed by the firmware being passed to the SEV * FW. Allocate enough memory for data structure + alignment * padding + SEV FW. */ data_size = ALIGN(sizeof(struct sev_data_download_firmware), 32); order = get_order(firmware->size + data_size); p = alloc_pages(GFP_KERNEL, order); if (!p) { ret = -1; goto fw_err; } /* * Copy firmware data to a kernel allocated contiguous * memory region. */ data = page_address(p); memcpy(page_address(p) + data_size, firmware->data, firmware->size); data->address = __psp_pa(page_address(p) + data_size); data->len = firmware->size; ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); /* * A quirk for fixing the committed TCB version, when upgrading from * earlier firmware version than 1.50. */ if (!ret && !sev_version_greater_or_equal(1, 50)) ret = sev_do_cmd(SEV_CMD_DOWNLOAD_FIRMWARE, data, &error); if (ret) dev_dbg(dev, "Failed to update SEV firmware: %#x\n", error); else dev_info(dev, "SEV firmware update successful\n"); __free_pages(p, order); fw_err: release_firmware(firmware); return ret; } static int sev_ioctl_do_pek_import(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_pek_cert_import input; struct sev_data_pek_cert_import data; void *pek_blob, *oca_blob; int ret; if (!writable) return -EPERM; if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; /* copy PEK certificate blobs from userspace */ pek_blob = psp_copy_user_blob(input.pek_cert_address, input.pek_cert_len); if (IS_ERR(pek_blob)) return PTR_ERR(pek_blob); data.reserved = 0; data.pek_cert_address = __psp_pa(pek_blob); data.pek_cert_len = input.pek_cert_len; /* copy PEK certificate blobs from userspace */ oca_blob = psp_copy_user_blob(input.oca_cert_address, input.oca_cert_len); if (IS_ERR(oca_blob)) { ret = PTR_ERR(oca_blob); goto e_free_pek; } data.oca_cert_address = __psp_pa(oca_blob); data.oca_cert_len = input.oca_cert_len; /* If platform is not in INIT state then transition it to INIT */ if (sev->state != SEV_STATE_INIT) { ret = __sev_platform_init_locked(&argp->error); if (ret) goto e_free_oca; } ret = __sev_do_cmd_locked(SEV_CMD_PEK_CERT_IMPORT, &data, &argp->error); e_free_oca: kfree(oca_blob); e_free_pek: kfree(pek_blob); return ret; } static int sev_ioctl_do_get_id2(struct sev_issue_cmd *argp) { struct sev_user_data_get_id2 input; struct sev_data_get_id data; void __user *input_address; void *id_blob = NULL; int ret; /* SEV GET_ID is available from SEV API v0.16 and up */ if (!sev_version_greater_or_equal(0, 16)) return -ENOTSUPP; if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; input_address = (void __user *)input.address; if (input.address && input.length) { /* * The length of the ID shouldn't be assumed by software since * it may change in the future. The allocation size is limited * to 1 << (PAGE_SHIFT + MAX_ORDER - 1) by the page allocator. * If the allocation fails, simply return ENOMEM rather than * warning in the kernel log. */ id_blob = kzalloc(input.length, GFP_KERNEL | __GFP_NOWARN); if (!id_blob) return -ENOMEM; data.address = __psp_pa(id_blob); data.len = input.length; } else { data.address = 0; data.len = 0; } ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, &data, &argp->error); /* * Firmware will return the length of the ID value (either the minimum * required length or the actual length written), return it to the user. */ input.length = data.len; if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { ret = -EFAULT; goto e_free; } if (id_blob) { if (copy_to_user(input_address, id_blob, data.len)) { ret = -EFAULT; goto e_free; } } e_free: kfree(id_blob); return ret; } static int sev_ioctl_do_get_id(struct sev_issue_cmd *argp) { struct sev_data_get_id *data; u64 data_size, user_size; void *id_blob, *mem; int ret; /* SEV GET_ID available from SEV API v0.16 and up */ if (!sev_version_greater_or_equal(0, 16)) return -ENOTSUPP; /* SEV FW expects the buffer it fills with the ID to be * 8-byte aligned. Memory allocated should be enough to * hold data structure + alignment padding + memory * where SEV FW writes the ID. */ data_size = ALIGN(sizeof(struct sev_data_get_id), 8); user_size = sizeof(struct sev_user_data_get_id); mem = kzalloc(data_size + user_size, GFP_KERNEL); if (!mem) return -ENOMEM; data = mem; id_blob = mem + data_size; data->address = __psp_pa(id_blob); data->len = user_size; ret = __sev_do_cmd_locked(SEV_CMD_GET_ID, data, &argp->error); if (!ret) { if (copy_to_user((void __user *)argp->data, id_blob, data->len)) ret = -EFAULT; } kfree(mem); return ret; } static int sev_ioctl_do_pdh_export(struct sev_issue_cmd *argp, bool writable) { struct sev_device *sev = psp_master->sev_data; struct sev_user_data_pdh_cert_export input; void *pdh_blob = NULL, *cert_blob = NULL; struct sev_data_pdh_cert_export data; void __user *input_cert_chain_address; void __user *input_pdh_cert_address; int ret; /* If platform is not in INIT state then transition it to INIT. */ if (sev->state != SEV_STATE_INIT) { if (!writable) return -EPERM; ret = __sev_platform_init_locked(&argp->error); if (ret) return ret; } if (copy_from_user(&input, (void __user *)argp->data, sizeof(input))) return -EFAULT; memset(&data, 0, sizeof(data)); /* Userspace wants to query the certificate length. */ if (!input.pdh_cert_address || !input.pdh_cert_len || !input.cert_chain_address) goto cmd; input_pdh_cert_address = (void __user *)input.pdh_cert_address; input_cert_chain_address = (void __user *)input.cert_chain_address; /* Allocate a physically contiguous buffer to store the PDH blob. */ if (input.pdh_cert_len > SEV_FW_BLOB_MAX_SIZE) return -EFAULT; /* Allocate a physically contiguous buffer to store the cert chain blob. */ if (input.cert_chain_len > SEV_FW_BLOB_MAX_SIZE) return -EFAULT; pdh_blob = kzalloc(input.pdh_cert_len, GFP_KERNEL); if (!pdh_blob) return -ENOMEM; data.pdh_cert_address = __psp_pa(pdh_blob); data.pdh_cert_len = input.pdh_cert_len; cert_blob = kzalloc(input.cert_chain_len, GFP_KERNEL); if (!cert_blob) { ret = -ENOMEM; goto e_free_pdh; } data.cert_chain_address = __psp_pa(cert_blob); data.cert_chain_len = input.cert_chain_len; cmd: ret = __sev_do_cmd_locked(SEV_CMD_PDH_CERT_EXPORT, &data, &argp->error); /* If we query the length, FW responded with expected data. */ input.cert_chain_len = data.cert_chain_len; input.pdh_cert_len = data.pdh_cert_len; if (copy_to_user((void __user *)argp->data, &input, sizeof(input))) { ret = -EFAULT; goto e_free_cert; } if (pdh_blob) { if (copy_to_user(input_pdh_cert_address, pdh_blob, input.pdh_cert_len)) { ret = -EFAULT; goto e_free_cert; } } if (cert_blob) { if (copy_to_user(input_cert_chain_address, cert_blob, input.cert_chain_len)) ret = -EFAULT; } e_free_cert: kfree(cert_blob); e_free_pdh: kfree(pdh_blob); return ret; } static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg) { void __user *argp = (void __user *)arg; struct sev_issue_cmd input; int ret = -EFAULT; bool writable = file->f_mode & FMODE_WRITE; if (!psp_master || !psp_master->sev_data) return -ENODEV; if (ioctl != SEV_ISSUE_CMD) return -EINVAL; if (copy_from_user(&input, argp, sizeof(struct sev_issue_cmd))) return -EFAULT; if (input.cmd > SEV_MAX) return -EINVAL; mutex_lock(&sev_cmd_mutex); switch (input.cmd) { case SEV_FACTORY_RESET: ret = sev_ioctl_do_reset(&input, writable); break; case SEV_PLATFORM_STATUS: ret = sev_ioctl_do_platform_status(&input); break; case SEV_PEK_GEN: ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PEK_GEN, &input, writable); break; case SEV_PDH_GEN: ret = sev_ioctl_do_pek_pdh_gen(SEV_CMD_PDH_GEN, &input, writable); break; case SEV_PEK_CSR: ret = sev_ioctl_do_pek_csr(&input, writable); break; case SEV_PEK_CERT_IMPORT: ret = sev_ioctl_do_pek_import(&input, writable); break; case SEV_PDH_CERT_EXPORT: ret = sev_ioctl_do_pdh_export(&input, writable); break; case SEV_GET_ID: pr_warn_once("SEV_GET_ID command is deprecated, use SEV_GET_ID2\n"); ret = sev_ioctl_do_get_id(&input); break; case SEV_GET_ID2: ret = sev_ioctl_do_get_id2(&input); break; default: ret = -EINVAL; goto out; } if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd))) ret = -EFAULT; out: mutex_unlock(&sev_cmd_mutex); return ret; } static const struct file_operations sev_fops = { .owner = THIS_MODULE, .unlocked_ioctl = sev_ioctl, }; int sev_platform_status(struct sev_user_data_status *data, int *error) { return sev_do_cmd(SEV_CMD_PLATFORM_STATUS, data, error); } EXPORT_SYMBOL_GPL(sev_platform_status); int sev_guest_deactivate(struct sev_data_deactivate *data, int *error) { return sev_do_cmd(SEV_CMD_DEACTIVATE, data, error); } EXPORT_SYMBOL_GPL(sev_guest_deactivate); int sev_guest_activate(struct sev_data_activate *data, int *error) { return sev_do_cmd(SEV_CMD_ACTIVATE, data, error); } EXPORT_SYMBOL_GPL(sev_guest_activate); int sev_guest_decommission(struct sev_data_decommission *data, int *error) { return sev_do_cmd(SEV_CMD_DECOMMISSION, data, error); } EXPORT_SYMBOL_GPL(sev_guest_decommission); int sev_guest_df_flush(int *error) { return sev_do_cmd(SEV_CMD_DF_FLUSH, NULL, error); } EXPORT_SYMBOL_GPL(sev_guest_df_flush); static void sev_exit(struct kref *ref) { misc_deregister(&misc_dev->misc); kfree(misc_dev); misc_dev = NULL; } static int sev_misc_init(struct sev_device *sev) { struct device *dev = sev->dev; int ret; /* * SEV feature support can be detected on multiple devices but the SEV * FW commands must be issued on the master. During probe, we do not * know the master hence we create /dev/sev on the first device probe. * sev_do_cmd() finds the right master device to which to issue the * command to the firmware. */ if (!misc_dev) { struct miscdevice *misc; misc_dev = kzalloc(sizeof(*misc_dev), GFP_KERNEL); if (!misc_dev) return -ENOMEM; misc = &misc_dev->misc; misc->minor = MISC_DYNAMIC_MINOR; misc->name = DEVICE_NAME; misc->fops = &sev_fops; ret = misc_register(misc); if (ret) return ret; kref_init(&misc_dev->refcount); } else { kref_get(&misc_dev->refcount); } init_waitqueue_head(&sev->int_queue); sev->misc = misc_dev; dev_dbg(dev, "registered SEV device\n"); return 0; } int sev_dev_init(struct psp_device *psp) { struct device *dev = psp->dev; struct sev_device *sev; int ret = -ENOMEM; if (!boot_cpu_has(X86_FEATURE_SEV)) { dev_info_once(dev, "SEV: memory encryption not enabled by BIOS\n"); return 0; } sev = devm_kzalloc(dev, sizeof(*sev), GFP_KERNEL); if (!sev) goto e_err; sev->cmd_buf = (void *)devm_get_free_pages(dev, GFP_KERNEL, 0); if (!sev->cmd_buf) goto e_sev; psp->sev_data = sev; sev->dev = dev; sev->psp = psp; sev->io_regs = psp->io_regs; sev->vdata = (struct sev_vdata *)psp->vdata->sev; if (!sev->vdata) { ret = -ENODEV; dev_err(dev, "sev: missing driver data\n"); goto e_buf; } psp_set_sev_irq_handler(psp, sev_irq_handler, sev); ret = sev_misc_init(sev); if (ret) goto e_irq; dev_notice(dev, "sev enabled\n"); return 0; e_irq: psp_clear_sev_irq_handler(psp); e_buf: devm_free_pages(dev, (unsigned long)sev->cmd_buf); e_sev: devm_kfree(dev, sev); e_err: psp->sev_data = NULL; dev_notice(dev, "sev initialization failed\n"); return ret; } static void sev_firmware_shutdown(struct sev_device *sev) { sev_platform_shutdown(NULL); if (sev_es_tmr) { /* The TMR area was encrypted, flush it from the cache */ wbinvd_on_all_cpus(); free_pages((unsigned long)sev_es_tmr, get_order(SEV_ES_TMR_SIZE)); sev_es_tmr = NULL; } if (sev_init_ex_buffer) { free_pages((unsigned long)sev_init_ex_buffer, get_order(NV_LENGTH)); sev_init_ex_buffer = NULL; } } void sev_dev_destroy(struct psp_device *psp) { struct sev_device *sev = psp->sev_data; if (!sev) return; sev_firmware_shutdown(sev); if (sev->misc) kref_put(&misc_dev->refcount, sev_exit); psp_clear_sev_irq_handler(psp); } int sev_issue_cmd_external_user(struct file *filep, unsigned int cmd, void *data, int *error) { if (!filep || filep->f_op != &sev_fops) return -EBADF; return sev_do_cmd(cmd, data, error); } EXPORT_SYMBOL_GPL(sev_issue_cmd_external_user); void sev_pci_init(void) { struct sev_device *sev = psp_master->sev_data; int error, rc; if (!sev) return; psp_timeout = psp_probe_timeout; if (sev_get_api_version()) goto err; if (sev_update_firmware(sev->dev) == 0) sev_get_api_version(); /* If an init_ex_path is provided rely on INIT_EX for PSP initialization * instead of INIT. */ if (init_ex_path) { sev_init_ex_buffer = sev_fw_alloc(NV_LENGTH); if (!sev_init_ex_buffer) { dev_err(sev->dev, "SEV: INIT_EX NV memory allocation failed\n"); goto err; } } /* Obtain the TMR memory area for SEV-ES use */ sev_es_tmr = sev_fw_alloc(SEV_ES_TMR_SIZE); if (sev_es_tmr) /* Must flush the cache before giving it to the firmware */ clflush_cache_range(sev_es_tmr, SEV_ES_TMR_SIZE); else dev_warn(sev->dev, "SEV: TMR allocation failed, SEV-ES support unavailable\n"); if (!psp_init_on_probe) return; /* Initialize the platform */ rc = sev_platform_init(&error); if (rc) dev_err(sev->dev, "SEV: failed to INIT error %#x, rc %d\n", error, rc); return; err: psp_master->sev_data = NULL; } void sev_pci_exit(void) { struct sev_device *sev = psp_master->sev_data; if (!sev) return; sev_firmware_shutdown(sev); }