| // 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 *)(uintptr_t)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; |
| } |