diff options
Diffstat (limited to 'lib/efi_loader/initrddump.c')
| -rw-r--r-- | lib/efi_loader/initrddump.c | 514 |
1 files changed, 514 insertions, 0 deletions
diff --git a/lib/efi_loader/initrddump.c b/lib/efi_loader/initrddump.c new file mode 100644 index 00000000000..98721069816 --- /dev/null +++ b/lib/efi_loader/initrddump.c @@ -0,0 +1,514 @@ +// 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. + * + * Specifying 'nocolor' as load option data suppresses colored output and + * clearing of the screen. + */ + +#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; +static bool nocolor; + +/* + * 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), + } +}; + +/** + * color() - set foreground color + * + * @color: foreground color + */ +static void color(u8 color) +{ + if (!nocolor) + cout->set_attribute(cout, color | EFI_BACKGROUND_BLACK); +} + +/** + * print() - print string + * + * @string: text + */ +static void print(u16 *string) +{ + cout->output_string(cout, string); +} + +/** + * cls() - clear screen + */ +static void cls(void) +{ + if (nocolor) + print(u"\r\n"); + else + cout->clear_screen(cout); +} + +/** + * error() - print error string + * + * @string: error text + */ +static void error(u16 *string) +{ + color(EFI_LIGHTRED); + print(string); + color(EFI_LIGHTBLUE); +} + +/* + * 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_drain_input() - drain console input + */ +static void efi_drain_input(void) +{ + cin->reset(cin, true); +} + +/** + * 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; + + 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] = u" "; + efi_status_t ret; + + *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(u"\r\nAborted\r\n"); + return EFI_ABORTED; + default: + break; + } + switch (key.unicode_char) { + case 0x08: /* Backspace */ + if (pos) { + buffer[pos--] = 0; + print(u"\b \b"); + } + break; + case 0x0a: /* Linefeed */ + case 0x0d: /* Carriage return */ + print(u"\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 if @string starts with the keyword + */ +static bool starts_with(u16 *string, u16 *keyword) +{ + if (!string || !keyword) + return false; + + for (; *keyword; ++string, ++keyword) { + if (*string != *keyword) + return false; + } + return true; +} + +/** + * do_help() - print help + */ +static void do_help(void) +{ + error(u"load - show length and CRC32 of initial RAM disk\r\n"); + error(u"save <initrd> - save initial RAM disk to file\r\n"); + error(u"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(u"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(u"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(u"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(u"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(u"length: 0x"); + printx(initrd_size, 1); + print(u"\r\n"); + + ret = bs->calculate_crc32(initrd, initrd_size, &crc32); + if (ret != EFI_SUCCESS) { + error(u"Calculating CRC32 failed\r\n"); + return EFI_LOAD_ERROR; + } + print(u"crc32: 0x"); + printx(crc32, 8); + print(u"\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(u"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(u"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(u"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); + efi_drain_input(); + print(u"Overwrite existing file (y/n)? "); + ret = efi_input_yn(); + print(u"\r\n"); + if (ret != EFI_SUCCESS) { + root->close(root); + error(u"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(u"Failed to write file\r\n"); + } else { + print(filename); + print(u" written\r\n"); + } + file->close(file); + } else { + error(u"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; +} + +/** + * get_load_options() - get load options + * + * Return: load options or NULL + */ +u16 *get_load_options(void) +{ + efi_status_t ret; + struct efi_loaded_image *loaded_image; + + ret = bs->open_protocol(handle, &loaded_image_guid, + (void **)&loaded_image, NULL, NULL, + EFI_OPEN_PROTOCOL_GET_PROTOCOL); + if (ret != EFI_SUCCESS) { + error(u"Loaded image protocol not found\r\n"); + return NULL; + } + + if (!loaded_image->load_options_size || !loaded_image->load_options) + return NULL; + + return loaded_image->load_options; +} + +/** + * 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) +{ + u16 *load_options; + + handle = image_handle; + systable = systab; + cerr = systable->std_err; + cout = systable->con_out; + cin = systable->con_in; + bs = systable->boottime; + load_options = get_load_options(); + + if (starts_with(load_options, u"nocolor")) + nocolor = true; + + color(EFI_WHITE); + cls(); + print(u"INITRD Dump\r\n===========\r\n\r\n"); + color(EFI_LIGHTBLUE); + + for (;;) { + u16 command[BUFFER_SIZE]; + u16 *pos; + efi_uintn_t ret; + + efi_drain_input(); + print(u"=> "); + ret = efi_input(command, sizeof(command)); + if (ret == EFI_ABORTED) + break; + pos = skip_whitespace(command); + if (starts_with(pos, u"exit")) + break; + else if (starts_with(pos, u"load")) + do_load(); + else if (starts_with(pos, u"save ")) + do_save(pos + 5); + else + do_help(); + } + + color(EFI_LIGHTGRAY); + cls(); + + return EFI_SUCCESS; +} |