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Diffstat (limited to '')
| -rw-r--r-- | drivers/crypto/ccp/sev-dev.c | 1370 |
1 files changed, 1370 insertions, 0 deletions
diff --git a/drivers/crypto/ccp/sev-dev.c b/drivers/crypto/ccp/sev-dev.c new file mode 100644 index 000000000..b8e02c3a1 --- /dev/null +++ b/drivers/crypto/ccp/sev-dev.c @@ -0,0 +1,1370 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * AMD Secure Encrypted Virtualization (SEV) interface + * + * Copyright (C) 2016,2019 Advanced Micro Devices, Inc. + * + * Author: Brijesh Singh <brijesh.singh@amd.com> + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/kthread.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/spinlock.h> +#include <linux/spinlock_types.h> +#include <linux/types.h> +#include <linux/mutex.h> +#include <linux/delay.h> +#include <linux/hw_random.h> +#include <linux/ccp.h> +#include <linux/firmware.h> +#include <linux/gfp.h> +#include <linux/cpufeature.h> +#include <linux/fs.h> +#include <linux/fs_struct.h> + +#include <asm/smp.h> +#include <asm/cacheflush.h> + +#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) +{ + int rc = 0, psp_ret = SEV_RET_NO_FW_CALL; + struct psp_device *psp = psp_master; + int (*init_function)(int *error); + struct sev_device *sev; + + 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); +} |