efi_selftest: add tests for setvariableRT

Since we support SetVariableRT now add the relevant tests

- Search for the RTStorageVolatile and VarToFile variables after EBS
- Try to update with invalid variales (BS, RT only)
- Try to write a variable bigger than our backend storage
- Write a variable that fits and check VarToFile has been updated
  correclty
- Append to the variable and check VarToFile changes
- Try to delete VarToFile which is write protected
- Try to add/delete runtime variables
- Verify VarToFile contains a valid file format

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

lib/efi_selftest/efi_selftest_variables_runtime.c

@@ -10,6 +10,8 @@
  */
 
 #include <efi_selftest.h>
+#include <efi_variable.h>
+#include <u-boot/crc.h>
 
 #define EFI_ST_MAX_DATA_SIZE 16
 #define EFI_ST_MAX_VARNAME_SIZE 40
@@ -17,6 +19,8 @@
 static struct efi_boot_services *boottime;
 static struct efi_runtime_services *runtime;
 static const efi_guid_t guid_vendor0 = EFI_GLOBAL_VARIABLE_GUID;
+static const efi_guid_t __efi_runtime_data efi_rt_var_guid =
+						U_BOOT_EFI_RT_VAR_FILE_GUID;
 
 /*
  * Setup unit test.
@@ -41,15 +45,18 @@ static int setup(const efi_handle_t img_handle,
 static int execute(void)
 {
 	efi_status_t ret;
-	efi_uintn_t len;
+	efi_uintn_t len, avail, append_len = 17;
 	u32 attr;
 	u8 v[16] = {0x5d, 0xd1, 0x5e, 0x51, 0x5a, 0x05, 0xc7, 0x0c,
 		    0x35, 0x4a, 0xae, 0x87, 0xa5, 0xdf, 0x0f, 0x65,};
+	u8 v2[CONFIG_EFI_VAR_BUF_SIZE];
 	u8 data[EFI_ST_MAX_DATA_SIZE];
+	u8 data2[CONFIG_EFI_VAR_BUF_SIZE];
 	u16 varname[EFI_ST_MAX_VARNAME_SIZE];
 	efi_guid_t guid;
 	u64 max_storage, rem_storage, max_size;
 
+	memset(v2, 0x1, sizeof(v2));
 	ret = runtime->query_variable_info(EFI_VARIABLE_BOOTSERVICE_ACCESS,
 					   &max_storage, &rem_storage,
 					   &max_size);
@@ -63,11 +70,210 @@ static int execute(void)
 				    EFI_VARIABLE_RUNTIME_ACCESS,
 				    3, v + 4);
 	if (IS_ENABLED(CONFIG_EFI_RT_VOLATILE_STORE)) {
+		efi_uintn_t prev_len, delta;
+		struct efi_var_entry *var;
+		struct efi_var_file *hdr;
+
 		/* At runtime only non-volatile variables may be set. */
 		if (ret != EFI_INVALID_PARAMETER) {
 			efi_st_error("SetVariable failed\n");
 			return EFI_ST_FAILURE;
 		}
+
+		/* runtime atttribute must be set */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    3, v + 4);
+		if (ret != EFI_INVALID_PARAMETER) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		len = sizeof(data);
+		ret = runtime->get_variable(u"RTStorageVolatile",
+					    &efi_rt_var_guid,
+					    &attr, &len, data);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("GetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		if (len != sizeof(EFI_VAR_FILE_NAME) ||
+		    memcmp(data, EFI_VAR_FILE_NAME, sizeof(EFI_VAR_FILE_NAME))) {
+			data[len - 1] = 0;
+			efi_st_error("RTStorageVolatile = %s\n", data);
+			return EFI_ST_FAILURE;
+		}
+
+		len = sizeof(data2);
+		ret = runtime->get_variable(u"VarToFile", &efi_rt_var_guid,
+					    &attr, &len, data2);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("GetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+		/*
+		 * VarToFile size must change once a variable is inserted
+		 * Store it now, we'll use it later
+		 */
+		prev_len = len;
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    sizeof(v2),
+					    v2);
+		/*
+		 * This will try to update VarToFile as well and must fail,
+		 * without changing or deleting VarToFile
+		 */
+		if (ret != EFI_OUT_OF_RESOURCES) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+		len = sizeof(data2);
+		ret = runtime->get_variable(u"VarToFile", &efi_rt_var_guid,
+					    &attr, &len, data2);
+		if (ret != EFI_SUCCESS || prev_len != len) {
+			efi_st_error("Get/SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Add an 8byte aligned variable */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    sizeof(v), v);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Delete it by setting the attrs to 0 */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    0, sizeof(v), v);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Add it back */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    sizeof(v), v);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Delete it again by setting the size to 0 */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    0, NULL);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Delete it again and make sure it's not there */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    0, NULL);
+		if (ret != EFI_NOT_FOUND) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/*
+		 * Add a non-aligned variable
+		 * VarToFile updates must include efi_st_var0
+		 */
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    9, v + 4);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+		var = efi_var_mem_find(&guid_vendor0, u"efi_st_var0", NULL);
+		if (!var) {
+			efi_st_error("GetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+		delta = efi_var_entry_len(var);
+		len = sizeof(data2);
+		ret = runtime->get_variable(u"VarToFile", &efi_rt_var_guid,
+					    &attr, &len, data2);
+		if (ret != EFI_SUCCESS || prev_len + delta != len) {
+			efi_st_error("Get/SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/*
+		 * Append on an existing variable must update VarToFile
+		 * Our variable entries are 8-byte aligned.
+		 * Adding a single byte will fit on the existing space
+		 */
+		prev_len = len;
+		avail = efi_var_entry_len(var) -
+			(sizeof(u16) * (u16_strlen(var->name) + 1) + sizeof(*var)) -
+			var->length;
+		if (avail >= append_len)
+			delta = 0;
+		else
+			delta = ALIGN(append_len - avail, 8);
+		ret = runtime->set_variable(u"efi_st_var0", &guid_vendor0,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_APPEND_WRITE |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    append_len, v2);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+		len = sizeof(data2);
+		ret = runtime->get_variable(u"VarToFile", &efi_rt_var_guid,
+					    &attr, &len, data2);
+		if (ret != EFI_SUCCESS) {
+			efi_st_error("GetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
+		if (prev_len + delta != len) {
+			efi_st_error("Unexpected VarToFile size");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Make sure that variable contains a valid file */
+		hdr = (struct efi_var_file *)data2;
+		if (hdr->magic != EFI_VAR_FILE_MAGIC ||
+		    len != hdr->length ||
+		    hdr->crc32 != crc32(0, (u8 *)((uintptr_t)data2 + sizeof(struct efi_var_file)),
+					len - sizeof(struct efi_var_file))) {
+			efi_st_error("VarToFile invalid header\n");
+			return EFI_ST_FAILURE;
+		}
+
+		/* Variables that are BS, RT and volatile are RO after EBS */
+		ret = runtime->set_variable(u"VarToFile", &efi_rt_var_guid,
+					    EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					    EFI_VARIABLE_RUNTIME_ACCESS |
+					    EFI_VARIABLE_NON_VOLATILE,
+					    sizeof(v), v);
+		if (ret != EFI_WRITE_PROTECTED) {
+			efi_st_error("Get/SetVariable failed\n");
+			return EFI_ST_FAILURE;
+		}
 	} else {
 		if (ret != EFI_UNSUPPORTED) {
 			efi_st_error("SetVariable failed\n");