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Diffstat (limited to 'lib/efi_loader/efi_variable_tee.c')
-rw-r--r--lib/efi_loader/efi_variable_tee.c1011
1 files changed, 1011 insertions, 0 deletions
diff --git a/lib/efi_loader/efi_variable_tee.c b/lib/efi_loader/efi_variable_tee.c
new file mode 100644
index 00000000000..8b6b0a39086
--- /dev/null
+++ b/lib/efi_loader/efi_variable_tee.c
@@ -0,0 +1,1011 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * EFI variable service via OP-TEE
+ *
+ * Copyright (C) 2019 Linaro Ltd. <sughosh.ganu@linaro.org>
+ * Copyright (C) 2019 Linaro Ltd. <ilias.apalodimas@linaro.org>
+ * Copyright 2022-2023 Arm Limited and/or its affiliates <open-source-office@arm.com>
+ *
+ * Authors:
+ * Abdellatif El Khlifi <abdellatif.elkhlifi@arm.com>
+ */
+
+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+#include <arm_ffa.h>
+#endif
+#include <cpu_func.h>
+#include <dm.h>
+#include <efi.h>
+#include <efi_api.h>
+#include <efi_loader.h>
+#include <efi_variable.h>
+#include <malloc.h>
+#include <mapmem.h>
+#include <mm_communication.h>
+#include <tee.h>
+
+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+/* MM return codes */
+#define MM_SUCCESS (0)
+#define MM_NOT_SUPPORTED (-1)
+#define MM_INVALID_PARAMETER (-2)
+#define MM_DENIED (-3)
+#define MM_NO_MEMORY (-5)
+
+static const char *mm_sp_svc_uuid = MM_SP_UUID;
+static u16 mm_sp_id;
+#endif
+
+extern struct efi_var_file __efi_runtime_data *efi_var_buf;
+static efi_uintn_t max_buffer_size; /* comm + var + func + data */
+static efi_uintn_t max_payload_size; /* func + data */
+
+struct mm_connection {
+ struct udevice *tee;
+ u32 session;
+};
+
+/**
+ * get_connection() - Retrieve OP-TEE session for a specific UUID.
+ *
+ * @conn: session buffer to fill
+ * Return: status code
+ */
+static int get_connection(struct mm_connection *conn)
+{
+ static const struct tee_optee_ta_uuid uuid = PTA_STMM_UUID;
+ struct udevice *tee = NULL;
+ struct tee_open_session_arg arg;
+ int rc = -ENODEV;
+
+ tee = tee_find_device(tee, NULL, NULL, NULL);
+ if (!tee)
+ goto out;
+
+ memset(&arg, 0, sizeof(arg));
+ tee_optee_ta_uuid_to_octets(arg.uuid, &uuid);
+ rc = tee_open_session(tee, &arg, 0, NULL);
+ if (rc)
+ goto out;
+
+ /* Check the internal OP-TEE result */
+ if (arg.ret != TEE_SUCCESS) {
+ rc = -EIO;
+ goto out;
+ }
+
+ conn->tee = tee;
+ conn->session = arg.session;
+
+ return 0;
+out:
+ return rc;
+}
+
+/**
+ * optee_mm_communicate() - Pass a buffer to StandaloneMM running in OP-TEE
+ *
+ * @comm_buf: locally allocted communcation buffer
+ * @dsize: buffer size
+ * Return: status code
+ */
+static efi_status_t optee_mm_communicate(void *comm_buf, ulong dsize)
+{
+ ulong buf_size;
+ efi_status_t ret;
+ struct efi_mm_communicate_header *mm_hdr;
+ struct mm_connection conn = { NULL, 0 };
+ struct tee_invoke_arg arg;
+ struct tee_param param[2];
+ struct tee_shm *shm = NULL;
+ int rc;
+
+ if (!comm_buf)
+ return EFI_INVALID_PARAMETER;
+
+ mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
+ buf_size = mm_hdr->message_len + sizeof(efi_guid_t) + sizeof(size_t);
+
+ if (dsize != buf_size)
+ return EFI_INVALID_PARAMETER;
+
+ rc = get_connection(&conn);
+ if (rc) {
+ log_err("Unable to open OP-TEE session (err=%d)\n", rc);
+ return EFI_UNSUPPORTED;
+ }
+
+ if (tee_shm_register(conn.tee, comm_buf, buf_size, 0, &shm)) {
+ log_err("Unable to register shared memory\n");
+ tee_close_session(conn.tee, conn.session);
+ return EFI_UNSUPPORTED;
+ }
+
+ memset(&arg, 0, sizeof(arg));
+ arg.func = PTA_STMM_CMDID_COMMUNICATE;
+ arg.session = conn.session;
+
+ memset(param, 0, sizeof(param));
+ param[0].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INOUT;
+ param[0].u.memref.size = buf_size;
+ param[0].u.memref.shm = shm;
+ param[1].attr = TEE_PARAM_ATTR_TYPE_VALUE_OUTPUT;
+
+ rc = tee_invoke_func(conn.tee, &arg, 2, param);
+ tee_shm_free(shm);
+ tee_close_session(conn.tee, conn.session);
+ if (rc)
+ return EFI_DEVICE_ERROR;
+ if (arg.ret == TEE_ERROR_EXCESS_DATA)
+ log_err("Variable payload too large\n");
+ if (arg.ret != TEE_SUCCESS)
+ return EFI_DEVICE_ERROR;
+
+ switch (param[1].u.value.a) {
+ case ARM_SVC_SPM_RET_SUCCESS:
+ ret = EFI_SUCCESS;
+ break;
+
+ case ARM_SVC_SPM_RET_INVALID_PARAMS:
+ ret = EFI_INVALID_PARAMETER;
+ break;
+
+ case ARM_SVC_SPM_RET_DENIED:
+ ret = EFI_ACCESS_DENIED;
+ break;
+
+ case ARM_SVC_SPM_RET_NO_MEMORY:
+ ret = EFI_OUT_OF_RESOURCES;
+ break;
+
+ default:
+ ret = EFI_ACCESS_DENIED;
+ }
+
+ return ret;
+}
+
+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+/**
+ * ffa_notify_mm_sp() - Announce there is data in the shared buffer
+ *
+ * Notify the MM partition in the trusted world that
+ * data is available in the shared buffer.
+ * This is a blocking call during which trusted world has exclusive access
+ * to the MM shared buffer.
+ *
+ * Return:
+ *
+ * 0 on success
+ */
+static int ffa_notify_mm_sp(void)
+{
+ struct ffa_send_direct_data msg = {0};
+ int ret;
+ int sp_event_ret;
+ struct udevice *dev;
+
+ ret = uclass_first_device_err(UCLASS_FFA, &dev);
+ if (ret) {
+ log_err("EFI: Cannot find FF-A bus device, notify MM SP failure\n");
+ return ret;
+ }
+
+ msg.data0 = CONFIG_FFA_SHARED_MM_BUF_OFFSET; /* x3 */
+
+ ret = ffa_sync_send_receive(dev, mm_sp_id, &msg, 1);
+ if (ret)
+ return ret;
+
+ sp_event_ret = msg.data0; /* x3 */
+
+ switch (sp_event_ret) {
+ case MM_SUCCESS:
+ ret = 0;
+ break;
+ case MM_NOT_SUPPORTED:
+ ret = -EINVAL;
+ break;
+ case MM_INVALID_PARAMETER:
+ ret = -EPERM;
+ break;
+ case MM_DENIED:
+ ret = -EACCES;
+ break;
+ case MM_NO_MEMORY:
+ ret = -EBUSY;
+ break;
+ default:
+ ret = -EACCES;
+ }
+
+ return ret;
+}
+
+/**
+ * ffa_discover_mm_sp_id() - Query the MM partition ID
+ *
+ * Use the FF-A driver to get the MM partition ID.
+ * If multiple partitions are found, use the first one.
+ * This is a boot time function.
+ *
+ * Return:
+ *
+ * 0 on success
+ */
+static int ffa_discover_mm_sp_id(void)
+{
+ u32 count = 0;
+ int ret;
+ struct ffa_partition_desc *descs;
+ struct udevice *dev;
+
+ ret = uclass_first_device_err(UCLASS_FFA, &dev);
+ if (ret) {
+ log_err("EFI: Cannot find FF-A bus device, MM SP discovery failure\n");
+ return ret;
+ }
+
+ /* Ask the driver to fill the buffer with the SPs info */
+ ret = ffa_partition_info_get(dev, mm_sp_svc_uuid, &count, &descs);
+ if (ret) {
+ log_err("EFI: Failure in querying SPs info (%d), MM SP discovery failure\n", ret);
+ return ret;
+ }
+
+ /* MM SPs found , use the first one */
+
+ mm_sp_id = descs[0].info.id;
+
+ log_info("EFI: MM partition ID 0x%x\n", mm_sp_id);
+
+ return 0;
+}
+
+/**
+ * ffa_mm_communicate() - Exchange EFI services data with the MM partition using FF-A
+ * @comm_buf: locally allocated communication buffer used for rx/tx
+ * @dsize: communication buffer size
+ *
+ * Issue a door bell event to notify the MM partition (SP) running in OP-TEE
+ * that there is data to read from the shared buffer.
+ * Communication with the MM SP is performed using FF-A transport.
+ * On the event, MM SP can read the data from the buffer and
+ * update the MM shared buffer with response data.
+ * The response data is copied back to the communication buffer.
+ *
+ * Return:
+ *
+ * EFI status code
+ */
+static efi_status_t ffa_mm_communicate(void *comm_buf, ulong comm_buf_size)
+{
+ ulong tx_data_size;
+ int ffa_ret;
+ efi_status_t efi_ret;
+ struct efi_mm_communicate_header *mm_hdr;
+ void *virt_shared_buf;
+
+ if (!comm_buf)
+ return EFI_INVALID_PARAMETER;
+
+ /* Discover MM partition ID at boot time */
+ if (!mm_sp_id && ffa_discover_mm_sp_id()) {
+ log_err("EFI: Failure to discover MM SP ID at boot time, FF-A MM comms failure\n");
+ return EFI_UNSUPPORTED;
+ }
+
+ mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
+ tx_data_size = mm_hdr->message_len + sizeof(efi_guid_t) + sizeof(size_t);
+
+ if (comm_buf_size != tx_data_size || tx_data_size > CONFIG_FFA_SHARED_MM_BUF_SIZE)
+ return EFI_INVALID_PARAMETER;
+
+ /* Copy the data to the shared buffer */
+
+ virt_shared_buf = map_sysmem((phys_addr_t)CONFIG_FFA_SHARED_MM_BUF_ADDR, 0);
+ memcpy(virt_shared_buf, comm_buf, tx_data_size);
+
+ /*
+ * The secure world might have cache disabled for
+ * the device region used for shared buffer (which is the case for Optee).
+ * In this case, the secure world reads the data from DRAM.
+ * Let's flush the cache so the DRAM is updated with the latest data.
+ */
+#ifdef CONFIG_ARM64
+ invalidate_dcache_all();
+#endif
+
+ /* Announce there is data in the shared buffer */
+
+ ffa_ret = ffa_notify_mm_sp();
+
+ switch (ffa_ret) {
+ case 0: {
+ ulong rx_data_size;
+ /* Copy the MM SP response from the shared buffer to the communication buffer */
+ rx_data_size = ((struct efi_mm_communicate_header *)virt_shared_buf)->message_len +
+ sizeof(efi_guid_t) +
+ sizeof(size_t);
+
+ if (rx_data_size > comm_buf_size) {
+ efi_ret = EFI_OUT_OF_RESOURCES;
+ break;
+ }
+
+ memcpy(comm_buf, virt_shared_buf, rx_data_size);
+ efi_ret = EFI_SUCCESS;
+ break;
+ }
+ case -EINVAL:
+ efi_ret = EFI_DEVICE_ERROR;
+ break;
+ case -EPERM:
+ efi_ret = EFI_INVALID_PARAMETER;
+ break;
+ case -EACCES:
+ efi_ret = EFI_ACCESS_DENIED;
+ break;
+ case -EBUSY:
+ efi_ret = EFI_OUT_OF_RESOURCES;
+ break;
+ default:
+ efi_ret = EFI_ACCESS_DENIED;
+ }
+
+ unmap_sysmem(virt_shared_buf);
+ return efi_ret;
+}
+
+/**
+ * get_mm_comms() - detect the available MM transport
+ *
+ * Make sure the FF-A bus is probed successfully
+ * which means FF-A communication with secure world works and ready
+ * for use.
+ *
+ * If FF-A bus is not ready, use OPTEE comms.
+ *
+ * Return:
+ *
+ * MM_COMMS_FFA or MM_COMMS_OPTEE
+ */
+static enum mm_comms_select get_mm_comms(void)
+{
+ struct udevice *dev;
+ int ret;
+
+ ret = uclass_first_device_err(UCLASS_FFA, &dev);
+ if (ret) {
+ log_debug("EFI: Cannot find FF-A bus device, trying Optee comms\n");
+ return MM_COMMS_OPTEE;
+ }
+
+ return MM_COMMS_FFA;
+}
+#endif
+
+/**
+ * mm_communicate() - Adjust the communication buffer to the MM SP and send
+ * it to OP-TEE
+ *
+ * @comm_buf: locally allocated communication buffer
+ * @dsize: buffer size
+ *
+ * The SP (also called partition) can be any MM SP such as StandAlonneMM or smm-gateway.
+ * The comm_buf format is the same for both partitions.
+ * When using the u-boot OP-TEE driver, StandAlonneMM is supported.
+ * When using the u-boot FF-A driver, any MM SP is supported.
+ *
+ * Return: status code
+ */
+static efi_status_t mm_communicate(u8 *comm_buf, efi_uintn_t dsize)
+{
+ efi_status_t ret;
+ struct efi_mm_communicate_header *mm_hdr;
+ struct smm_variable_communicate_header *var_hdr;
+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+ enum mm_comms_select mm_comms;
+#endif
+
+ dsize += MM_COMMUNICATE_HEADER_SIZE + MM_VARIABLE_COMMUNICATE_SIZE;
+ mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
+ var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data;
+
+#if CONFIG_IS_ENABLED(ARM_FFA_TRANSPORT)
+ mm_comms = get_mm_comms();
+ if (mm_comms == MM_COMMS_FFA)
+ ret = ffa_mm_communicate(comm_buf, dsize);
+ else
+ ret = optee_mm_communicate(comm_buf, dsize);
+#else
+ ret = optee_mm_communicate(comm_buf, dsize);
+#endif
+
+ if (ret != EFI_SUCCESS) {
+ log_err("%s failed!\n", __func__);
+ return ret;
+ }
+
+ return var_hdr->ret_status;
+}
+
+/**
+ * setup_mm_hdr() - Allocate a buffer for StandAloneMM and initialize the
+ * header data.
+ *
+ * @dptr: pointer address of the corresponding StandAloneMM
+ * function
+ * @payload_size: buffer size
+ * @func: standAloneMM function number
+ * @ret: EFI return code
+ * Return: buffer or NULL
+ */
+static u8 *setup_mm_hdr(void **dptr, efi_uintn_t payload_size,
+ efi_uintn_t func, efi_status_t *ret)
+{
+ const efi_guid_t mm_var_guid = EFI_MM_VARIABLE_GUID;
+ struct efi_mm_communicate_header *mm_hdr;
+ struct smm_variable_communicate_header *var_hdr;
+ u8 *comm_buf;
+
+ /* In the init function we initialize max_buffer_size with
+ * get_max_payload(). So skip the test if max_buffer_size is initialized
+ * StandAloneMM will perform similar checks and drop the buffer if it's
+ * too long
+ */
+ if (max_buffer_size && max_buffer_size <
+ (MM_COMMUNICATE_HEADER_SIZE +
+ MM_VARIABLE_COMMUNICATE_SIZE +
+ payload_size)) {
+ *ret = EFI_INVALID_PARAMETER;
+ return NULL;
+ }
+
+ comm_buf = calloc(1, MM_COMMUNICATE_HEADER_SIZE +
+ MM_VARIABLE_COMMUNICATE_SIZE +
+ payload_size);
+ if (!comm_buf) {
+ *ret = EFI_OUT_OF_RESOURCES;
+ return NULL;
+ }
+
+ mm_hdr = (struct efi_mm_communicate_header *)comm_buf;
+ guidcpy(&mm_hdr->header_guid, &mm_var_guid);
+ mm_hdr->message_len = MM_VARIABLE_COMMUNICATE_SIZE + payload_size;
+
+ var_hdr = (struct smm_variable_communicate_header *)mm_hdr->data;
+ var_hdr->function = func;
+ if (dptr)
+ *dptr = var_hdr->data;
+ *ret = EFI_SUCCESS;
+
+ return comm_buf;
+}
+
+/**
+ * get_max_payload() - Get variable payload size from StandAloneMM.
+ *
+ * @size: size of the variable in storage
+ * Return: status code
+ */
+efi_status_t EFIAPI get_max_payload(efi_uintn_t *size)
+{
+ struct smm_variable_payload_size *var_payload = NULL;
+ efi_uintn_t payload_size;
+ u8 *comm_buf = NULL;
+ efi_status_t ret;
+
+ if (!size) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ payload_size = sizeof(*var_payload);
+ comm_buf = setup_mm_hdr((void **)&var_payload, payload_size,
+ SMM_VARIABLE_FUNCTION_GET_PAYLOAD_SIZE, &ret);
+ if (!comm_buf)
+ goto out;
+
+ ret = mm_communicate(comm_buf, payload_size);
+ if (ret != EFI_SUCCESS)
+ goto out;
+
+ /* Make sure the buffer is big enough for storing variables */
+ if (var_payload->size < MM_VARIABLE_ACCESS_HEADER_SIZE + 0x20) {
+ ret = EFI_DEVICE_ERROR;
+ goto out;
+ }
+ *size = var_payload->size;
+ /*
+ * There seems to be a bug in EDK2 miscalculating the boundaries and
+ * size checks, so deduct 2 more bytes to fulfill this requirement. Fix
+ * it up here to ensure backwards compatibility with older versions
+ * (cf. StandaloneMmPkg/Drivers/StandaloneMmCpu/AArch64/EventHandle.c.
+ * sizeof (EFI_MM_COMMUNICATE_HEADER) instead the size minus the
+ * flexible array member).
+ *
+ * size is guaranteed to be > 2 due to checks on the beginning.
+ */
+ *size -= 2;
+out:
+ free(comm_buf);
+ return ret;
+}
+
+/*
+ * StMM can store internal attributes and properties for variables, i.e enabling
+ * R/O variables
+ */
+static efi_status_t set_property_int(const u16 *variable_name,
+ efi_uintn_t name_size,
+ const efi_guid_t *vendor,
+ struct var_check_property *var_property)
+{
+ struct smm_variable_var_check_property *smm_property;
+ efi_uintn_t payload_size;
+ u8 *comm_buf = NULL;
+ efi_status_t ret;
+
+ payload_size = sizeof(*smm_property) + name_size;
+ if (payload_size > max_payload_size) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+ comm_buf = setup_mm_hdr((void **)&smm_property, payload_size,
+ SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_SET,
+ &ret);
+ if (!comm_buf)
+ goto out;
+
+ guidcpy(&smm_property->guid, vendor);
+ smm_property->name_size = name_size;
+ memcpy(&smm_property->property, var_property,
+ sizeof(smm_property->property));
+ memcpy(smm_property->name, variable_name, name_size);
+
+ ret = mm_communicate(comm_buf, payload_size);
+
+out:
+ free(comm_buf);
+ return ret;
+}
+
+static efi_status_t get_property_int(const u16 *variable_name,
+ efi_uintn_t name_size,
+ const efi_guid_t *vendor,
+ struct var_check_property *var_property)
+{
+ struct smm_variable_var_check_property *smm_property;
+ efi_uintn_t payload_size;
+ u8 *comm_buf = NULL;
+ efi_status_t ret;
+
+ memset(var_property, 0, sizeof(*var_property));
+ payload_size = sizeof(*smm_property) + name_size;
+ if (payload_size > max_payload_size) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+ comm_buf = setup_mm_hdr((void **)&smm_property, payload_size,
+ SMM_VARIABLE_FUNCTION_VAR_CHECK_VARIABLE_PROPERTY_GET,
+ &ret);
+ if (!comm_buf)
+ goto out;
+
+ guidcpy(&smm_property->guid, vendor);
+ smm_property->name_size = name_size;
+ memcpy(smm_property->name, variable_name, name_size);
+
+ ret = mm_communicate(comm_buf, payload_size);
+ /*
+ * Currently only R/O property is supported in StMM.
+ * Variables that are not set to R/O will not set the property in StMM
+ * and the call will return EFI_NOT_FOUND. We are setting the
+ * properties to 0x0 so checking against that is enough for the
+ * EFI_NOT_FOUND case.
+ */
+ if (ret == EFI_NOT_FOUND)
+ ret = EFI_SUCCESS;
+ if (ret != EFI_SUCCESS)
+ goto out;
+ memcpy(var_property, &smm_property->property, sizeof(*var_property));
+
+out:
+ free(comm_buf);
+ return ret;
+}
+
+efi_status_t efi_get_variable_int(const u16 *variable_name,
+ const efi_guid_t *vendor,
+ u32 *attributes, efi_uintn_t *data_size,
+ void *data, u64 *timep)
+{
+ struct var_check_property var_property;
+ struct smm_variable_access *var_acc;
+ efi_uintn_t payload_size;
+ efi_uintn_t name_size;
+ efi_uintn_t tmp_dsize;
+ u8 *comm_buf = NULL;
+ efi_status_t ret, tmp;
+
+ if (!variable_name || !vendor || !data_size) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ /* Check payload size */
+ name_size = u16_strsize(variable_name);
+ if (name_size > max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ /* Trim output buffer size */
+ tmp_dsize = *data_size;
+ if (name_size + tmp_dsize >
+ max_payload_size - MM_VARIABLE_ACCESS_HEADER_SIZE) {
+ tmp_dsize = max_payload_size -
+ MM_VARIABLE_ACCESS_HEADER_SIZE -
+ name_size;
+ }
+
+ /* Get communication buffer and initialize header */
+ payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + tmp_dsize;
+ comm_buf = setup_mm_hdr((void **)&var_acc, payload_size,
+ SMM_VARIABLE_FUNCTION_GET_VARIABLE, &ret);
+ if (!comm_buf)
+ goto out;
+
+ /* Fill in contents */
+ guidcpy(&var_acc->guid, vendor);
+ var_acc->data_size = tmp_dsize;
+ var_acc->name_size = name_size;
+ var_acc->attr = attributes ? *attributes : 0;
+ memcpy(var_acc->name, variable_name, name_size);
+
+ /* Communicate */
+ ret = mm_communicate(comm_buf, payload_size);
+ if (ret != EFI_SUCCESS && ret != EFI_BUFFER_TOO_SMALL)
+ goto out;
+
+ /* Update with reported data size for trimmed case */
+ *data_size = var_acc->data_size;
+ /*
+ * UEFI > 2.7 needs the attributes set even if the buffer is
+ * smaller
+ */
+ if (attributes) {
+ tmp = get_property_int(variable_name, name_size, vendor,
+ &var_property);
+ if (tmp != EFI_SUCCESS) {
+ ret = tmp;
+ goto out;
+ }
+ *attributes = var_acc->attr;
+ if (var_property.property &
+ VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)
+ *attributes |= EFI_VARIABLE_READ_ONLY;
+ }
+
+ /* return if ret is EFI_BUFFER_TOO_SMALL */
+ if (ret != EFI_SUCCESS)
+ goto out;
+
+ if (data)
+ memcpy(data, (u8 *)var_acc->name + var_acc->name_size,
+ var_acc->data_size);
+ else
+ ret = EFI_INVALID_PARAMETER;
+
+out:
+ free(comm_buf);
+ return ret;
+}
+
+efi_status_t efi_get_next_variable_name_int(efi_uintn_t *variable_name_size,
+ u16 *variable_name,
+ efi_guid_t *guid)
+{
+ struct smm_variable_getnext *var_getnext;
+ efi_uintn_t payload_size;
+ efi_uintn_t out_name_size;
+ efi_uintn_t in_name_size;
+ u8 *comm_buf = NULL;
+ efi_status_t ret;
+
+ if (!variable_name_size || !variable_name || !guid) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ out_name_size = *variable_name_size;
+ in_name_size = u16_strsize(variable_name);
+
+ if (out_name_size < in_name_size) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ if (in_name_size > max_payload_size - MM_VARIABLE_GET_NEXT_HEADER_SIZE) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ /* Trim output buffer size */
+ if (out_name_size > max_payload_size - MM_VARIABLE_GET_NEXT_HEADER_SIZE)
+ out_name_size = max_payload_size - MM_VARIABLE_GET_NEXT_HEADER_SIZE;
+
+ payload_size = MM_VARIABLE_GET_NEXT_HEADER_SIZE + out_name_size;
+ comm_buf = setup_mm_hdr((void **)&var_getnext, payload_size,
+ SMM_VARIABLE_FUNCTION_GET_NEXT_VARIABLE_NAME,
+ &ret);
+ if (!comm_buf)
+ goto out;
+
+ /* Fill in contents */
+ guidcpy(&var_getnext->guid, guid);
+ var_getnext->name_size = out_name_size;
+ memcpy(var_getnext->name, variable_name, in_name_size);
+ memset((u8 *)var_getnext->name + in_name_size, 0x0,
+ out_name_size - in_name_size);
+
+ /* Communicate */
+ ret = mm_communicate(comm_buf, payload_size);
+ if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) {
+ /* Update with reported data size for trimmed case */
+ *variable_name_size = var_getnext->name_size;
+ }
+ if (ret != EFI_SUCCESS)
+ goto out;
+
+ guidcpy(guid, &var_getnext->guid);
+ memcpy(variable_name, var_getnext->name, var_getnext->name_size);
+
+out:
+ free(comm_buf);
+ return ret;
+}
+
+efi_status_t efi_set_variable_int(const u16 *variable_name,
+ const efi_guid_t *vendor, u32 attributes,
+ efi_uintn_t data_size, const void *data,
+ bool ro_check)
+{
+ efi_status_t ret, alt_ret = EFI_SUCCESS;
+ struct var_check_property var_property;
+ struct smm_variable_access *var_acc;
+ efi_uintn_t payload_size;
+ efi_uintn_t name_size;
+ u8 *comm_buf = NULL;
+ bool ro;
+
+ if (!variable_name || variable_name[0] == 0 || !vendor) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+ if (data_size > 0 && !data) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+ /* Check payload size */
+ name_size = u16_strsize(variable_name);
+ payload_size = MM_VARIABLE_ACCESS_HEADER_SIZE + name_size + data_size;
+ if (payload_size > max_payload_size) {
+ ret = EFI_INVALID_PARAMETER;
+ goto out;
+ }
+
+ /*
+ * Allocate the buffer early, before switching to RW (if needed)
+ * so we won't need to account for any failures in reading/setting
+ * the properties, if the allocation fails
+ */
+ comm_buf = setup_mm_hdr((void **)&var_acc, payload_size,
+ SMM_VARIABLE_FUNCTION_SET_VARIABLE, &ret);
+ if (!comm_buf)
+ goto out;
+
+ ro = !!(attributes & EFI_VARIABLE_READ_ONLY);
+ attributes &= EFI_VARIABLE_MASK;
+
+ /*
+ * The API has the ability to override RO flags. If no RO check was
+ * requested switch the variable to RW for the duration of this call
+ */
+ ret = get_property_int(variable_name, name_size, vendor,
+ &var_property);
+ if (ret != EFI_SUCCESS)
+ goto out;
+
+ if (var_property.property & VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY) {
+ /* Bypass r/o check */
+ if (!ro_check) {
+ var_property.property &= ~VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY;
+ ret = set_property_int(variable_name, name_size, vendor, &var_property);
+ if (ret != EFI_SUCCESS)
+ goto out;
+ } else {
+ ret = EFI_WRITE_PROTECTED;
+ goto out;
+ }
+ }
+
+ /* Fill in contents */
+ guidcpy(&var_acc->guid, vendor);
+ var_acc->data_size = data_size;
+ var_acc->name_size = name_size;
+ var_acc->attr = attributes;
+ memcpy(var_acc->name, variable_name, name_size);
+ memcpy((u8 *)var_acc->name + name_size, data, data_size);
+
+ /* Communicate */
+ ret = mm_communicate(comm_buf, payload_size);
+ if (ret != EFI_SUCCESS)
+ alt_ret = ret;
+
+ if (ro && !(var_property.property & VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY)) {
+ var_property.revision = VAR_CHECK_VARIABLE_PROPERTY_REVISION;
+ var_property.property |= VAR_CHECK_VARIABLE_PROPERTY_READ_ONLY;
+ var_property.attributes = attributes;
+ var_property.minsize = 1;
+ var_property.maxsize = var_acc->data_size;
+ ret = set_property_int(variable_name, name_size, vendor, &var_property);
+ }
+
+ if (alt_ret != EFI_SUCCESS)
+ goto out;
+
+ if (!u16_strcmp(variable_name, u"PK"))
+ alt_ret = efi_init_secure_state();
+out:
+ free(comm_buf);
+ return alt_ret == EFI_SUCCESS ? ret : alt_ret;
+}
+
+efi_status_t efi_query_variable_info_int(u32 attributes,
+ u64 *max_variable_storage_size,
+ u64 *remain_variable_storage_size,
+ u64 *max_variable_size)
+{
+ struct smm_variable_query_info *mm_query_info;
+ efi_uintn_t payload_size;
+ efi_status_t ret;
+ u8 *comm_buf;
+
+ if (!max_variable_storage_size ||
+ !remain_variable_storage_size ||
+ !max_variable_size || !attributes)
+ return EFI_INVALID_PARAMETER;
+
+ payload_size = sizeof(*mm_query_info);
+ comm_buf = setup_mm_hdr((void **)&mm_query_info, payload_size,
+ SMM_VARIABLE_FUNCTION_QUERY_VARIABLE_INFO,
+ &ret);
+ if (!comm_buf)
+ goto out;
+
+ mm_query_info->attr = attributes;
+ ret = mm_communicate(comm_buf, payload_size);
+ if (ret != EFI_SUCCESS)
+ goto out;
+ *max_variable_storage_size = mm_query_info->max_variable_storage;
+ *remain_variable_storage_size =
+ mm_query_info->remaining_variable_storage;
+ *max_variable_size = mm_query_info->max_variable_size;
+
+out:
+ free(comm_buf);
+ return ret;
+}
+
+/**
+ * efi_query_variable_info() - get information about EFI variables
+ *
+ * This function implements the QueryVariableInfo() runtime service.
+ *
+ * See the Unified Extensible Firmware Interface (UEFI) specification for
+ * details.
+ *
+ * @attributes: bitmask to select variables to be
+ * queried
+ * @maximum_variable_storage_size: maximum size of storage area for the
+ * selected variable types
+ * @remaining_variable_storage_size: remaining size of storage are for the
+ * selected variable types
+ * @maximum_variable_size: maximum size of a variable of the
+ * selected type
+ * Return: status code
+ */
+efi_status_t EFIAPI __efi_runtime
+efi_query_variable_info_runtime(u32 attributes, u64 *max_variable_storage_size,
+ u64 *remain_variable_storage_size,
+ u64 *max_variable_size)
+{
+ return EFI_UNSUPPORTED;
+}
+
+/**
+ * efi_set_variable_runtime() - runtime implementation of SetVariable()
+ *
+ * @variable_name: name of the variable
+ * @guid: vendor GUID
+ * @attributes: attributes of the variable
+ * @data_size: size of the buffer with the variable value
+ * @data: buffer with the variable value
+ * Return: status code
+ */
+static efi_status_t __efi_runtime EFIAPI
+efi_set_variable_runtime(u16 *variable_name, const efi_guid_t *guid,
+ u32 attributes, efi_uintn_t data_size,
+ const void *data)
+{
+ return EFI_UNSUPPORTED;
+}
+
+/**
+ * efi_variables_boot_exit_notify() - notify ExitBootServices() is called
+ */
+void efi_variables_boot_exit_notify(void)
+{
+ efi_status_t ret;
+ u8 *comm_buf;
+ loff_t len;
+ struct efi_var_file *var_buf;
+
+ comm_buf = setup_mm_hdr(NULL, 0,
+ SMM_VARIABLE_FUNCTION_EXIT_BOOT_SERVICE, &ret);
+ if (comm_buf)
+ ret = mm_communicate(comm_buf, 0);
+ else
+ ret = EFI_NOT_FOUND;
+
+ if (ret != EFI_SUCCESS)
+ log_err("Unable to notify the MM partition for ExitBootServices\n");
+ free(comm_buf);
+
+ ret = efi_var_collect(&var_buf, &len, EFI_VARIABLE_RUNTIME_ACCESS);
+ if (ret != EFI_SUCCESS)
+ log_err("Can't populate EFI variables. No runtime variables will be available\n");
+ else
+ efi_var_buf_update(var_buf);
+ free(var_buf);
+
+ /* Update runtime service table */
+ efi_runtime_services.query_variable_info =
+ efi_query_variable_info_runtime;
+ efi_runtime_services.get_variable = efi_get_variable_runtime;
+ efi_runtime_services.get_next_variable_name =
+ efi_get_next_variable_name_runtime;
+ efi_runtime_services.set_variable = efi_set_variable_runtime;
+ efi_update_table_header_crc32(&efi_runtime_services.hdr);
+}
+
+/**
+ * efi_init_variables() - initialize variable services
+ *
+ * Return: status code
+ */
+efi_status_t efi_init_variables(void)
+{
+ efi_status_t ret;
+
+ /* Create a cached copy of the variables that will be enabled on ExitBootServices() */
+ ret = efi_var_mem_init();
+ if (ret != EFI_SUCCESS)
+ return ret;
+
+ ret = get_max_payload(&max_payload_size);
+ if (ret != EFI_SUCCESS)
+ return ret;
+
+ max_buffer_size = MM_COMMUNICATE_HEADER_SIZE +
+ MM_VARIABLE_COMMUNICATE_SIZE +
+ max_payload_size;
+
+ ret = efi_init_secure_state();
+ if (ret != EFI_SUCCESS)
+ return ret;
+
+ return EFI_SUCCESS;
+}
generated by cgit v1.2.3 (git 2.0.4) at 2025-07-26 06:42:37 +0000