efi_selftest: provide initrddump test tool

Provide an UEFI application to save the initial RAM disk provided by U-Boot
via the Load File2 protocol.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>

lib/efi_selftest/Makefile

@@ -14,6 +14,8 @@ CFLAGS_efi_selftest_miniapp_exit.o := $(CFLAGS_EFI) -Os -ffreestanding
 CFLAGS_REMOVE_efi_selftest_miniapp_exit.o := $(CFLAGS_NON_EFI)
 CFLAGS_efi_selftest_miniapp_return.o := $(CFLAGS_EFI) -Os -ffreestanding
 CFLAGS_REMOVE_efi_selftest_miniapp_return.o := $(CFLAGS_NON_EFI)
+CFLAGS_initrddump_exit.o := $(CFLAGS_EFI) -Os -ffreestanding
+CFLAGS_REMOVE_initrddump.o := $(CFLAGS_NON_EFI)
 
 obj-y += \
 efi_selftest.o \
@@ -82,6 +84,10 @@ ifeq ($(CONFIG_GENERATE_ACPI_TABLE),)
 always += dtbdump.efi
 endif
 
+ifdef CONFIG_EFI_LOAD_FILE2_INITRD
+always += initrddump.efi
+endif
+
 $(obj)/efi_miniapp_file_image_exception.h: $(obj)/efi_selftest_miniapp_exception.efi
 	$(obj)/../../tools/file2include $(obj)/efi_selftest_miniapp_exception.efi > \
 	$(obj)/efi_miniapp_file_image_exception.h

lib/efi_selftest/efi_selftest_console.c

@@ -46,11 +46,10 @@ static void mac(void *pointer, u16 **buf)
 /*
  * printx() - print hexadecimal number to an u16 string
  *
- * @pointer:	pointer
+ * @p:		value to print
  * @prec:	minimum number of digits to print
  * @buf:	pointer to buffer address,
  *		on return position of terminating zero word
- * @size:	size of value to be printed in bytes
  */
 static void printx(u64 p, int prec, u16 **buf)
 {

lib/efi_selftest/initrddump.c

+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2020, Heinrich Schuchardt <xypron.glpk@gmx.de>
+ *
+ * initrddump.efi saves the initial RAM disk provided via the
+ * EFI_LOAD_FILE2_PROTOCOL.
+ */
+
+#include <common.h>
+#include <efi_api.h>
+#include <efi_load_initrd.h>
+
+#define BUFFER_SIZE 64
+#define ESC 0x17
+
+#define efi_size_in_pages(size) (((size) + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT)
+
+static struct efi_system_table *systable;
+static struct efi_boot_services *bs;
+static struct efi_simple_text_output_protocol *cerr;
+static struct efi_simple_text_output_protocol *cout;
+static struct efi_simple_text_input_protocol *cin;
+static const efi_guid_t loaded_image_guid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
+static const efi_guid_t guid_simple_file_system_protocol =
+					EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
+static const efi_guid_t load_file2_guid = EFI_LOAD_FILE2_PROTOCOL_GUID;
+static efi_handle_t handle;
+
+/*
+ * Device path defined by Linux to identify the handle providing the
+ * EFI_LOAD_FILE2_PROTOCOL used for loading the initial ramdisk.
+ */
+static const struct efi_initrd_dp initrd_dp = {
+	.vendor = {
+		{
+		   DEVICE_PATH_TYPE_MEDIA_DEVICE,
+		   DEVICE_PATH_SUB_TYPE_VENDOR_PATH,
+		   sizeof(initrd_dp.vendor),
+		},
+		EFI_INITRD_MEDIA_GUID,
+	},
+	.end = {
+		DEVICE_PATH_TYPE_END,
+		DEVICE_PATH_SUB_TYPE_END,
+		sizeof(initrd_dp.end),
+	}
+};
+
+/**
+ * print() - print string
+ *
+ * @string:	text
+ */
+static void print(u16 *string)
+{
+	cout->output_string(cout, string);
+}
+
+/**
+ * error() - print error string
+ *
+ * @string:	error text
+ */
+static void error(u16 *string)
+{
+	cout->set_attribute(cout, EFI_LIGHTRED | EFI_BACKGROUND_BLACK);
+	print(string);
+	cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
+}
+
+/*
+ * printx() - print hexadecimal number
+ *
+ * @val:	value to print;
+ * @prec:	minimum number of digits to print
+ */
+static void printx(u64 val, u32 prec)
+{
+	int i;
+	u16 c;
+	u16 buf[16];
+	u16 *pos = buf;
+
+	for (i = 2 * sizeof(val) - 1; i >= 0; --i) {
+		c = (val >> (4 * i)) & 0x0f;
+		if (c || pos != buf || !i || i < prec) {
+			c += '0';
+			if (c > '9')
+				c += 'a' - '9' - 1;
+			*pos++ = c;
+		}
+	}
+	*pos = 0;
+	print(buf);
+}
+
+/**
+ * efi_input_yn() - get answer to yes/no question
+ *
+ * Return:
+ * y or Y
+ *     EFI_SUCCESS
+ * n or N
+ *     EFI_ACCESS_DENIED
+ * ESC
+ *     EFI_ABORTED
+ */
+static efi_status_t efi_input_yn(void)
+{
+	struct efi_input_key key = {0};
+	efi_uintn_t index;
+	efi_status_t ret;
+
+	/* Drain the console input */
+	ret = cin->reset(cin, true);
+	for (;;) {
+		ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
+		if (ret != EFI_SUCCESS)
+			continue;
+		ret = cin->read_key_stroke(cin, &key);
+		if (ret != EFI_SUCCESS)
+			continue;
+		switch (key.scan_code) {
+		case 0x17: /* Escape */
+			return EFI_ABORTED;
+		default:
+			break;
+		}
+		/* Convert to lower case */
+		switch (key.unicode_char | 0x20) {
+		case 'y':
+			return EFI_SUCCESS;
+		case 'n':
+			return EFI_ACCESS_DENIED;
+		default:
+			break;
+		}
+	}
+}
+
+/**
+ * efi_input() - read string from console
+ *
+ * @buffer:		input buffer
+ * @buffer_size:	buffer size
+ * Return:		status code
+ */
+static efi_status_t efi_input(u16 *buffer, efi_uintn_t buffer_size)
+{
+	struct efi_input_key key = {0};
+	efi_uintn_t index;
+	efi_uintn_t pos = 0;
+	u16 outbuf[2] = L" ";
+	efi_status_t ret;
+
+	/* Drain the console input */
+	ret = cin->reset(cin, true);
+	*buffer = 0;
+	for (;;) {
+		ret = bs->wait_for_event(1, &cin->wait_for_key, &index);
+		if (ret != EFI_SUCCESS)
+			continue;
+		ret = cin->read_key_stroke(cin, &key);
+		if (ret != EFI_SUCCESS)
+			continue;
+		switch (key.scan_code) {
+		case 0x17: /* Escape */
+			print(L"\r\nAborted\r\n");
+			return EFI_ABORTED;
+		default:
+			break;
+		}
+		switch (key.unicode_char) {
+		case 0x08: /* Backspace */
+			if (pos) {
+				buffer[pos--] = 0;
+				print(L"\b \b");
+			}
+			break;
+		case 0x0a: /* Linefeed */
+		case 0x0d: /* Carriage return */
+			print(L"\r\n");
+			return EFI_SUCCESS;
+		default:
+			break;
+		}
+		/* Ignore surrogate codes */
+		if (key.unicode_char >= 0xD800 && key.unicode_char <= 0xDBFF)
+			continue;
+		if (key.unicode_char >= 0x20 &&
+		    pos < buffer_size - 1) {
+			*outbuf = key.unicode_char;
+			buffer[pos++] = key.unicode_char;
+			buffer[pos] = 0;
+			print(outbuf);
+		}
+	}
+}
+
+/**
+ * skip_whitespace() - skip over leading whitespace
+ *
+ * @pos:	UTF-16 string
+ * Return:	pointer to first non-whitespace
+ */
+static u16 *skip_whitespace(u16 *pos)
+{
+	for (; *pos && *pos <= 0x20; ++pos)
+		;
+	return pos;
+}
+
+/**
+ * starts_with() - check if @string starts with @keyword
+ *
+ * @string:	string to search for keyword
+ * @keyword:	keyword to be searched
+ * Return:	true fi @string starts with the keyword
+ */
+static bool starts_with(u16 *string, u16 *keyword)
+{
+	for (; *keyword; ++string, ++keyword) {
+		if (*string != *keyword)
+			return false;
+	}
+	return true;
+}
+
+/**
+ * do_help() - print help
+ */
+static void do_help(void)
+{
+	error(L"load          - show length and CRC32 of initial RAM disk\r\n");
+	error(L"save <initrd> - save initial RAM disk to file\r\n");
+	error(L"exit          - exit the shell\r\n");
+}
+
+/**
+ * get_initrd() - read initial RAM disk via EFI_LOAD_FILE2_PROTOCOL
+ *
+ * @initrd:		on return buffer with initial RAM disk
+ * @initrd_size:	size of initial RAM disk
+ * Return:		status code
+ */
+static efi_status_t get_initrd(void **initrd, efi_uintn_t *initrd_size)
+{
+	struct efi_device_path *dp = (struct efi_device_path *)&initrd_dp;
+	struct efi_load_file_protocol *load_file2_prot;
+	u64 buffer;
+	efi_handle_t handle;
+	efi_status_t ret;
+
+	*initrd = NULL;
+	*initrd_size = 0;
+	ret = bs->locate_device_path(&load_file2_guid, &dp, &handle);
+	if (ret != EFI_SUCCESS) {
+		error(L"Load File2 protocol not found\r\n");
+		return ret;
+	}
+	ret = bs->handle_protocol(handle, &load_file2_guid,
+				 (void **)&load_file2_prot);
+	ret = load_file2_prot->load_file(load_file2_prot, dp, false,
+					 initrd_size, NULL);
+	if (ret != EFI_BUFFER_TOO_SMALL) {
+		error(L"Load File2 protocol does not provide file length\r\n");
+		return EFI_LOAD_ERROR;
+	}
+	ret = bs->allocate_pages(EFI_ALLOCATE_ANY_PAGES, EFI_LOADER_DATA,
+				 efi_size_in_pages(*initrd_size), &buffer);
+	if (ret != EFI_SUCCESS) {
+		error(L"Out of memory\r\n");
+		return ret;
+	}
+	*initrd = (void *)buffer;
+	ret = load_file2_prot->load_file(load_file2_prot, dp, false,
+					 initrd_size, *initrd);
+	if (ret != EFI_SUCCESS) {
+		error(L"Load File2 protocol failed to provide file\r\n");
+		bs->free_pages(buffer, efi_size_in_pages(*initrd_size));
+		return EFI_LOAD_ERROR;
+	}
+	return ret;
+}
+
+/**
+ * do_load() - load initial RAM disk and display CRC32 and length
+ *
+ * @filename:	file name
+ * Return:	status code
+ */
+static efi_status_t do_load(void)
+{
+	void *initrd;
+	efi_uintn_t initrd_size;
+	u32 crc32;
+	efi_uintn_t ret;
+
+	ret =  get_initrd(&initrd, &initrd_size);
+	if (ret != EFI_SUCCESS)
+		return ret;
+	print(L"length: 0x");
+	printx(initrd_size, 1);
+	print(L"\r\n");
+
+	ret = bs->calculate_crc32(initrd, initrd_size, &crc32);
+	if (ret != EFI_SUCCESS) {
+		error(L"Calculating CRC32 failed\r\n");
+		return EFI_LOAD_ERROR;
+	}
+	print(L"crc32: 0x");
+	printx(crc32, 8);
+	print(L"\r\n");
+
+	return EFI_SUCCESS;
+}
+
+/**
+ * do_save() - save initial RAM disk
+ *
+ * @filename:	file name
+ * Return:	status code
+ */
+static efi_status_t do_save(u16 *filename)
+{
+	struct efi_loaded_image *loaded_image;
+	struct efi_simple_file_system_protocol *file_system;
+	struct efi_file_handle *root, *file;
+	void *initrd;
+	efi_uintn_t initrd_size;
+	efi_uintn_t ret;
+
+	ret = get_initrd(&initrd, &initrd_size);
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	filename = skip_whitespace(filename);
+
+	ret = bs->open_protocol(handle, &loaded_image_guid,
+				(void **)&loaded_image, NULL, NULL,
+				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
+	if (ret != EFI_SUCCESS) {
+		error(L"Loaded image protocol not found\r\n");
+		goto out;
+	}
+
+	/* Open the simple file system protocol */
+	ret = bs->open_protocol(loaded_image->device_handle,
+				&guid_simple_file_system_protocol,
+				(void **)&file_system, NULL, NULL,
+				EFI_OPEN_PROTOCOL_GET_PROTOCOL);
+	if (ret != EFI_SUCCESS) {
+		error(L"Failed to open simple file system protocol\r\n");
+		goto out;
+	}
+
+	/* Open volume */
+	ret = file_system->open_volume(file_system, &root);
+	if (ret != EFI_SUCCESS) {
+		error(L"Failed to open volume\r\n");
+		goto out;
+	}
+	/* Check if file already exists */
+	ret = root->open(root, &file, filename, EFI_FILE_MODE_READ, 0);
+	if (ret == EFI_SUCCESS) {
+		file->close(file);
+		print(L"Overwrite existing file (y/n)? ");
+		ret = efi_input_yn();
+		print(L"\r\n");
+		if (ret != EFI_SUCCESS) {
+			root->close(root);
+			error(L"Aborted by user\r\n");
+			goto out;
+		}
+	}
+
+	/* Create file */
+	ret = root->open(root, &file, filename,
+			 EFI_FILE_MODE_READ | EFI_FILE_MODE_WRITE |
+			 EFI_FILE_MODE_CREATE, EFI_FILE_ARCHIVE);
+	if (ret == EFI_SUCCESS) {
+		/* Write file */
+		ret = file->write(file, &initrd_size, initrd);
+		if (ret != EFI_SUCCESS) {
+			error(L"Failed to write file\r\n");
+		} else {
+			print(filename);
+			print(L" written\r\n");
+		}
+		file->close(file);
+	} else {
+		error(L"Failed to open file\r\n");
+	}
+	root->close(root);
+
+out:
+	if (initrd)
+		bs->free_pages((uintptr_t)initrd,
+			       efi_size_in_pages(initrd_size));
+	return ret;
+}
+
+/**
+ * efi_main() - entry point of the EFI application.
+ *
+ * @handle:	handle of the loaded image
+ * @systab:	system table
+ * @return:	status code
+ */
+efi_status_t EFIAPI efi_main(efi_handle_t image_handle,
+			     struct efi_system_table *systab)
+{
+	handle = image_handle;
+	systable = systab;
+	cerr = systable->std_err;
+	cout = systable->con_out;
+	cin = systable->con_in;
+	bs = systable->boottime;
+
+	cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
+	cout->clear_screen(cout);
+	cout->set_attribute(cout, EFI_WHITE | EFI_BACKGROUND_BLACK);
+	print(L"INITRD Dump\r\n========\r\n\r\n");
+	cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
+
+	for (;;) {
+		u16 command[BUFFER_SIZE];
+		u16 *pos;
+		efi_uintn_t ret;
+
+		print(L"=> ");
+		ret = efi_input(command, sizeof(command));
+		if (ret == EFI_ABORTED)
+			break;
+		pos = skip_whitespace(command);
+		if (starts_with(pos, L"exit"))
+			break;
+		else if (starts_with(pos, L"load"))
+			do_load();
+		else if (starts_with(pos, L"save "))
+			do_save(pos + 5);
+		else
+			do_help();
+	}
+
+	cout->set_attribute(cout, EFI_LIGHTGRAY | EFI_BACKGROUND_BLACK);
+	cout->clear_screen(cout);
+	return EFI_SUCCESS;
+}