Hi Heinrich,
On Sun, Jan 17, 2021 at 07:48:18AM +0100, Heinrich Schuchardt wrote:
> 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.g...@gmx.de>
> ---
> lib/efi_selftest/Makefile | 6 +
> lib/efi_selftest/initrddump.c | 378 ++++++++++++++++++++++++++++++++++
> 2 files changed, 384 insertions(+)
> create mode 100644 lib/efi_selftest/initrddump.c
>
> diff --git a/lib/efi_selftest/Makefile b/lib/efi_selftest/Makefile
> index fa3dc66baa..7d6ea30102 100644
> --- a/lib/efi_selftest/Makefile
> +++ b/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
> diff --git a/lib/efi_selftest/initrddump.c b/lib/efi_selftest/initrddump.c
> new file mode 100644
> index 0000000000..e0d578d440
> --- /dev/null
> +++ b/lib/efi_selftest/initrddump.c
> @@ -0,0 +1,378 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2020, Heinrich Schuchardt <xypron.g...@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),
> + }
> +};
> +
> +/**
> + * error() - print error string
> + *
> + * @string: error text
> + */
> +static void error(u16 *string)
> +{
> + cout->set_attribute(cout, EFI_LIGHTRED | EFI_BACKGROUND_BLACK);
> + cout->output_string(cout, string);
> + cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
> +}
> +
> +/**
> + * 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 */
> + cout->output_string(cout, L"\nAborted\n");
> + return EFI_ABORTED;
> + default:
> + break;
> + }
> + switch (key.unicode_char) {
> + case 0x08: /* Backspace */
> + if (pos) {
> + buffer[pos--] = 0;
> + cout->output_string(cout, L"\b \b");
> + }
> + break;
> + case 0x0a: /* Linefeed */
> + case 0x0d: /* Carriage return */
> + cout->output_string(cout, L"\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;
> + cout->output_string(cout, 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"save <initrd> - save initial RAM disk to file\n");
> + error(L"exit - exit the shell\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\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\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\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\n");
> + bs->free_pages(buffer, efi_size_in_pages(*initrd_size));
> + return EFI_LOAD_ERROR;
> + }
> + return ret;
> +}
> +
> +/**
> + * 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\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\n");
> + goto out;
> + }
> +
> + /* Open volume */
> + ret = file_system->open_volume(file_system, &root);
> + if (ret != EFI_SUCCESS) {
> + error(L"Failed to open volume\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);
> + cout->output_string(cout, L"Overwrite existing file (y/n)? ");
> + ret = efi_input_yn();
> + cout->output_string(cout, L"\n");
> + if (ret != EFI_SUCCESS) {
> + root->close(root);
> + error(L"Aborted by user\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\n");
> + } else {
> + cout->output_string(cout, filename);
> + cout->output_string(cout, L" written\n");
> + }
> + file->close(file);
> + } else {
> + error(L"Failed to open file\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);
> + cout->output_string(cout, L"INITRD Dump\n========\n\n");
> + cout->set_attribute(cout, EFI_LIGHTBLUE | EFI_BACKGROUND_BLACK);
> +
> + for (;;) {
> + u16 command[BUFFER_SIZE];
> + u16 *pos;
> + efi_uintn_t ret;
> +
> + cout->output_string(cout, 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"save "))
> + do_save(pos + 5);
> + else
> + do_help();
> + }
> +
> + cout->set_attribute(cout, EFI_LIGHTGRAY | EFI_BACKGROUND_BLACK);
> + cout->clear_screen(cout);
> + return EFI_SUCCESS;
> +}
> --
> 2.29.2
>
I guess we can use this in the selftests for initrd loading in the future
right?
This seems to be covering most of the protocol usage, so the self-test could
be something like 'download file' -> check md5sum/sha256(or similar) of the
saved file against the one we loaded.
Acked-by: Ilias Apalodimas <ilias.apalodi...@linaro.org>
