/* Copyright 2018 The Chromium OS Authors. All rights reserved. * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. * * A reference implementation for AP (and supporting images) firmware updater. */ #include #include #include #include #include #include #include #include "2common.h" #include "2rsa.h" #include "crossystem.h" #include "fmap.h" #include "futility.h" #include "host_misc.h" #include "updater.h" #include "utility.h" #include "util_misc.h" #include "vb2_common.h" #include "vb2_struct.h" #define COMMAND_BUFFER_SIZE 256 #define RETURN_ON_FAILURE(x) do {int r = (x); if (r) return r;} while (0); #define FLASHROM_OUTPUT_WP_PATTERN "write protect is " #define REMOVE_WP_URL "https://goo.gl/ces83U" /* System environment values. */ static const char * const FWACT_A = "A", * const FWACT_B = "B", * const STR_REV = "rev", * const FLASHROM_OUTPUT_WP_ENABLED = FLASHROM_OUTPUT_WP_PATTERN "enabled", * const FLASHROM_OUTPUT_WP_DISABLED = FLASHROM_OUTPUT_WP_PATTERN "disabled"; /* flashrom programmers. */ static const char * const PROG_HOST = "host", * const PROG_EC = "ec", * const PROG_PD = "ec:dev=1"; static const char ROOTKEY_HASH_DEV[] = "b11d74edd286c144e1135b49e7f0bc20cf041f10"; enum wp_state { WP_DISABLED, WP_ENABLED, }; enum target_type { TARGET_SELF, TARGET_UPDATE, }; enum active_slot { SLOT_UNKNOWN = -1, SLOT_A = 0, SLOT_B, }; enum flashrom_ops { FLASHROM_READ, FLASHROM_WRITE, FLASHROM_WP_STATUS, }; enum rootkey_compat_result { ROOTKEY_COMPAT_OK, ROOTKEY_COMPAT_ERROR, ROOTKEY_COMPAT_REKEY, ROOTKEY_COMPAT_REKEY_TO_DEV, }; /* * Helper function to create a new temporary file. * All files created will be removed by updater_remove_all_temp_files(). * Returns the path of new file, or NULL on failure. */ const char *updater_create_temp_file(struct updater_config *cfg) { struct tempfile *new_temp; char new_path[] = P_tmpdir "/fwupdater.XXXXXX"; int fd; fd = mkstemp(new_path); if (fd < 0) { ERROR("Failed to create new temp file in %s\n", new_path); return NULL; } close(fd); new_temp = (struct tempfile *)malloc(sizeof(*new_temp)); if (new_temp) new_temp->filepath = strdup(new_path); if (!new_temp || !new_temp->filepath) { remove(new_path); free(new_temp); ERROR("Failed to allocate buffer for new temp file.\n"); return NULL; } VB2_DEBUG("Created new temporary file: %s.\n", new_path); new_temp->next = cfg->tempfiles; cfg->tempfiles = new_temp; return new_temp->filepath; } /* * Helper function to remove all files created by create_temp_file(). * This is intended to be called only once at end of program execution. */ static void updater_remove_all_temp_files(struct updater_config *cfg) { struct tempfile *tempfiles = cfg->tempfiles; while (tempfiles != NULL) { struct tempfile *target = tempfiles; VB2_DEBUG("Remove temporary file: %s.\n", target->filepath); remove(target->filepath); free(target->filepath); tempfiles = target->next; free(target); } cfg->tempfiles = NULL; } /* * Strip a string (usually from shell execution output) by removing all the * trailing characters in pattern. If pattern is NULL, match by space type * characters (space, new line, tab, ... etc). */ static void strip(char *s, const char *pattern) { int len; assert(s); len = strlen(s); while (len-- > 0) { if (pattern) { if (!strchr(pattern, s[len])) break; } else { if (!isascii(s[len]) || !isspace(s[len])) break; } s[len] = '\0'; } } /* * Executes a command on current host and returns stripped command output. * If the command has failed (exit code is not zero), returns an empty string. * The caller is responsible for releasing the returned string. */ char *host_shell(const char *command) { /* Currently all commands we use do not have large output. */ char buf[COMMAND_BUFFER_SIZE]; int result; FILE *fp = popen(command, "r"); VB2_DEBUG("%s\n", command); buf[0] = '\0'; if (!fp) { VB2_DEBUG("Execution error for %s.\n", command); return strdup(buf); } if (fgets(buf, sizeof(buf), fp)) strip(buf, NULL); result = pclose(fp); if (!WIFEXITED(result) || WEXITSTATUS(result) != 0) { VB2_DEBUG("Execution failure with exit code %d: %s\n", WEXITSTATUS(result), command); /* * Discard all output if command failed, for example command * syntax failure may lead to garbage in stdout. */ buf[0] = '\0'; } return strdup(buf); } /* An helper function to return "mainfw_act" system property. */ static int host_get_mainfw_act(void) { char buf[VB_MAX_STRING_PROPERTY]; if (!VbGetSystemPropertyString("mainfw_act", buf, sizeof(buf))) return SLOT_UNKNOWN; if (strcmp(buf, FWACT_A) == 0) return SLOT_A; else if (strcmp(buf, FWACT_B) == 0) return SLOT_B; return SLOT_UNKNOWN; } /* A helper function to return the "tpm_fwver" system property. */ static int host_get_tpm_fwver(void) { return VbGetSystemPropertyInt("tpm_fwver"); } /* A helper function to return the "hardware write protection" status. */ static int host_get_wp_hw(void) { /* wpsw refers to write protection 'switch', not 'software'. */ int v = VbGetSystemPropertyInt("wpsw_cur"); /* wpsw_cur may be not available, especially in recovery mode. */ if (v < 0) v = VbGetSystemPropertyInt("wpsw_boot"); return v; } /* A helper function to return "fw_vboot2" system property. */ static int host_get_fw_vboot2(void) { return VbGetSystemPropertyInt("fw_vboot2"); } /* A help function to get $(mosys platform version). */ static int host_get_platform_version(void) { char *result = host_shell("mosys platform version"); long rev = -1; /* Result should be 'revN' */ if (strncmp(result, STR_REV, strlen(STR_REV)) == 0) rev = strtol(result + strlen(STR_REV), NULL, 0); /* we should never have negative or extremely large versions, * but clamp just to be sure */ if (rev < 0) rev = 0; if (rev > INT_MAX) rev = INT_MAX; VB2_DEBUG("Raw data = [%s], parsed version is %ld\n", result, rev); free(result); return rev; } /* * A helper function to invoke flashrom(8) command. * Returns 0 if success, non-zero if error. */ static int host_flashrom(enum flashrom_ops op, const char *image_path, const char *programmer, int verbose, const char *section_name, const char *extra) { char *command, *result; const char *op_cmd, *dash_i = "-i", *postfix = ""; int r; switch (verbose) { case 0: postfix = " >/dev/null 2>&1"; break; case 1: break; case 2: postfix = "-V"; break; case 3: postfix = "-V -V"; break; default: postfix = "-V -V -V"; break; } if (!section_name || !*section_name) { dash_i = ""; section_name = ""; } switch (op) { case FLASHROM_READ: op_cmd = "-r"; assert(image_path); break; case FLASHROM_WRITE: op_cmd = "-w"; assert(image_path); break; case FLASHROM_WP_STATUS: op_cmd = "--wp-status"; assert(image_path == NULL); image_path = ""; /* grep is needed because host_shell only returns 1 line. */ postfix = " 2>/dev/null | grep \"" \ FLASHROM_OUTPUT_WP_PATTERN "\""; break; default: assert(0); return -1; } if (!extra) extra = ""; /* TODO(hungte) In future we should link with flashrom directly. */ ASPRINTF(&command, "flashrom %s %s -p %s %s %s %s %s", op_cmd, image_path, programmer, dash_i, section_name, extra, postfix); if (verbose) INFO("Executing: %s\n", command); if (op != FLASHROM_WP_STATUS) { r = system(command); free(command); if (r) ERROR("Error code: %d\n", r); return r; } result = host_shell(command); strip(result, NULL); free(command); VB2_DEBUG("wp-status: %s\n", result); if (strstr(result, FLASHROM_OUTPUT_WP_ENABLED)) r = WP_ENABLED; else if (strstr(result, FLASHROM_OUTPUT_WP_DISABLED)) r = WP_DISABLED; else r = -1; free(result); return r; } /* Helper function to return write protection status via given programmer. */ static int host_get_wp(const char *programmer) { return host_flashrom(FLASHROM_WP_STATUS, NULL, programmer, 0, NULL, NULL); } /* Helper function to return host software write protection status. */ static int host_get_wp_sw(void) { return host_get_wp(PROG_HOST); } /* * Gets the system property by given type. * If the property was not loaded yet, invoke the property getter function * and cache the result. * Returns the property value. */ int get_system_property(enum system_property_type property_type, struct updater_config *cfg) { struct system_property *prop; assert(property_type < SYS_PROP_MAX); prop = &cfg->system_properties[property_type]; if (!prop->initialized) { prop->initialized = 1; prop->value = prop->getter(); } return prop->value; } static void print_system_properties(struct updater_config *cfg) { int i; /* * There may be error messages when fetching properties from active * system, so we want to peek at them first and then print out. */ VB2_DEBUG("Scanning system properties...\n"); for (i = 0; i < SYS_PROP_MAX; i++) { get_system_property((enum system_property_type)i, cfg); } printf("System properties: ["); for (i = 0; i < SYS_PROP_MAX; i++) { printf("%d,", get_system_property((enum system_property_type)i, cfg)); } printf("]\n"); } /* * Overrides the return value of a system property. * After invoked, next call to get_system_property(type, cfg) will return * the given value. */ static void override_system_property(enum system_property_type property_type, struct updater_config *cfg, int value) { struct system_property *prop; assert(property_type < SYS_PROP_MAX); prop = &cfg->system_properties[property_type]; prop->initialized = 1; prop->value = value; } /* * Overrides system properties from a given list. * The list should be string of integers eliminated by comma and/or space. * For example, "1 2 3" and "1,2,3" both overrides first 3 properties. * To skip some properties you have to use comma, for example * "1, , 3" will only override the first and 3rd properties. * Invalid characters and fields will be ignored. * * The current implementation is only for unit testing. * In future we may extend this with name=value so users can use it easily on * actual systems. */ static void override_properties_from_list(const char *override_list, struct updater_config *cfg) { const char *s = override_list; char *e, c; int i = 0, wait_comma = 0; long int v; VB2_DEBUG("Input is <%s>\n", override_list); for (c = *s; c; c = *++s) { if (c == ',') { if (!wait_comma) i++; wait_comma = 0; } if (!isascii(c) || !(isdigit(c) || c == '-')) continue; if (i >= SYS_PROP_MAX) { ERROR("Too many fields (max is %d): %s.\n", SYS_PROP_MAX, override_list); return; } v = strtol(s, &e, 0); s = e - 1; VB2_DEBUG("property[%d].value = %ld\n", i, v); override_system_property((enum system_property_type)i, cfg, v); wait_comma = 1; i++; } } /* Gets the value (setting) of specified quirks from updater configuration. */ int get_config_quirk(enum quirk_types quirk, const struct updater_config *cfg) { assert(quirk < QUIRK_MAX); return cfg->quirks[quirk].value; } /* Prints the name and description from all supported quirks. */ void updater_list_config_quirks(const struct updater_config *cfg) { const struct quirk_entry *entry = cfg->quirks; int i; printf("Supported quirks:\n"); for (i = 0; i < QUIRK_MAX; i++, entry++) { printf(" '%s': %s (default: %d)\n", entry->name, entry->help ? entry->help : "(no description)", get_config_quirk((enum quirk_types)i, cfg)); } } /* * Applies a quirk if applicable (the value should be non-zero). * Returns 0 on success, otherwise failure. */ static int try_apply_quirk(enum quirk_types quirk, struct updater_config *cfg) { const struct quirk_entry *entry = cfg->quirks + quirk; assert(quirk < QUIRK_MAX); if (!entry->value) return 0; if (!entry->apply) { ERROR("<%s> not implemented.\n", entry->name); return -1; } VB2_DEBUG("Applying quirk <%s>.\n", entry->name); return entry->apply(cfg); } /* * Initialize the updater_config quirks from a list of settings. * Returns 0 on success, otherwise failure. */ static int setup_config_quirks(const char *quirks, struct updater_config *cfg) { /* * The list should be in NAME[=VALUE],... * Value defaults to 1 if not specified. */ int r = 0; char *buf = strdup(quirks); char *token; token = strtok(buf, ", "); for (; token; token = strtok(NULL, ", ")) { const char *name = token; char *equ = strchr(token, '='); int i, value = 1; struct quirk_entry *entry = cfg->quirks; if (equ) { *equ = '\0'; value = strtol(equ + 1, NULL, 0); } VB2_DEBUG("Looking for quirk <%s=%d>.\n", name, value); for (i = 0; i < QUIRK_MAX; i++, entry++) { if (strcmp(name, entry->name)) continue; entry->value = value; VB2_DEBUG("Set quirk %s to %d.\n", entry->name, value); break; } if (i >= QUIRK_MAX) { ERROR("Unknown quirk: %s\n", name); r++; } } free(buf); return r; } /* * Finds a firmware section by given name in the firmware image. * If successful, return zero and *section argument contains the address and * size of the section; otherwise failure. */ int find_firmware_section(struct firmware_section *section, const struct firmware_image *image, const char *section_name) { FmapAreaHeader *fah = NULL; uint8_t *ptr; section->data = NULL; section->size = 0; ptr = fmap_find_by_name( image->data, image->size, image->fmap_header, section_name, &fah); if (!ptr) return -1; section->data = (uint8_t *)ptr; section->size = fah->area_size; return 0; } /* * Returns true if the given FMAP section exists in the firmware image. */ static int firmware_section_exists(const struct firmware_image *image, const char *section_name) { struct firmware_section section; find_firmware_section(§ion, image, section_name); return section.data != NULL; } /* * Checks if the section is filled with given character. * If section size is 0, return 0. If section is not empty, return non-zero if * the section is filled with same character c, otherwise 0. */ static int section_is_filled_with(const struct firmware_section *section, uint8_t c) { uint32_t i; if (!section->size) return 0; for (i = 0; i < section->size; i++) if (section->data[i] != c) return 0; return 1; } /* * Loads the firmware information from an FMAP section in loaded firmware image. * The section should only contain ASCIIZ string as firmware version. * If successful, the return value is zero and *version points to a newly * allocated string as firmware version (caller must free it); otherwise * failure. */ static int load_firmware_version(struct firmware_image *image, const char *section_name, char **version) { struct firmware_section fwid; find_firmware_section(&fwid, image, section_name); if (fwid.size) { *version = strndup((const char*)fwid.data, fwid.size); /* * For 'system current' images, the version string may contain * invalid characters that we do want to strip. */ strip(*version, "\xff"); return 0; } *version = strdup(""); return -1; } /* * Loads a firmware image from file. * If archive is provided and file_name is a relative path, read the file from * archive. * Returns 0 on success, otherwise failure. */ int load_firmware_image(struct firmware_image *image, const char *file_name, struct archive *archive) { if (!file_name) { ERROR("No file name given\n"); return -1; } VB2_DEBUG("Load image file from %s...\n", file_name); if (!archive_has_entry(archive, file_name)) { ERROR("Does not exist: %s\n", file_name); return -1; } if (archive_read_file(archive, file_name, &image->data, &image->size) != VB2_SUCCESS) { ERROR("Failed to load %s\n", file_name); return -1; } VB2_DEBUG("Image size: %d\n", image->size); assert(image->data); image->file_name = strdup(file_name); image->fmap_header = fmap_find(image->data, image->size); if (!image->fmap_header) { ERROR("Invalid image file (missing FMAP): %s\n", file_name); return -1; } if (!firmware_section_exists(image, FMAP_RO_FRID)) { ERROR("Does not look like VBoot firmware image: %s\n", file_name); return -1; } load_firmware_version(image, FMAP_RO_FRID, &image->ro_version); if (firmware_section_exists(image, FMAP_RW_FWID_A)) { char **a = &image->rw_version_a, **b = &image->rw_version_b; load_firmware_version(image, FMAP_RW_FWID_A, a); load_firmware_version(image, FMAP_RW_FWID_B, b); } else if (firmware_section_exists(image, FMAP_RW_FWID)) { char **a = &image->rw_version_a, **b = &image->rw_version_b; load_firmware_version(image, FMAP_RW_FWID, a); load_firmware_version(image, FMAP_RW_FWID, b); } else { ERROR("Unsupported VBoot firmware (no RW ID): %s\n", file_name); } return 0; } /* * Loads the active system firmware image (usually from SPI flash chip). * Returns 0 if success, non-zero if error. */ int load_system_firmware(struct updater_config *cfg, struct firmware_image *image) { const char *tmp_file = updater_create_temp_file(cfg); if (!tmp_file) return -1; RETURN_ON_FAILURE(host_flashrom( FLASHROM_READ, tmp_file, image->programmer, cfg->verbosity, NULL, NULL)); return load_firmware_image(image, tmp_file, NULL); } /* * Frees the allocated resource from a firmware image object. */ void free_firmware_image(struct firmware_image *image) { /* * The programmer is not allocated by load_firmware_image and must be * preserved explicitly. */ const char *programmer = image->programmer; free(image->data); free(image->file_name); free(image->ro_version); free(image->rw_version_a); free(image->rw_version_b); memset(image, 0, sizeof(*image)); image->programmer = programmer; } /* * Decides which target in RW firmware to manipulate. * The `target` argument specifies if we want to know "the section to be * update" (TARGET_UPDATE), or "the (active) section * to check" (TARGET_SELF). * Returns the section name if success, otherwise NULL. */ static const char *decide_rw_target(struct updater_config *cfg, enum target_type target, int is_vboot2) { const char *a = FMAP_RW_SECTION_A, *b = FMAP_RW_SECTION_B; int slot = get_system_property(SYS_PROP_MAINFW_ACT, cfg); /* In vboot1, always update B and check content with A. */ if (!is_vboot2) return target == TARGET_UPDATE ? b : a; switch (slot) { case SLOT_A: return target == TARGET_UPDATE ? b : a; case SLOT_B: return target == TARGET_UPDATE ? a : b; } return NULL; } /* * Sets any needed system properties to indicate system should try the new * firmware on next boot. * The `target` argument is an FMAP section name indicating which to try. * Returns 0 if success, non-zero if error. */ static int set_try_cookies(struct updater_config *cfg, const char *target, int is_vboot2) { int tries = 6; const char *slot; /* EC Software Sync needs few more reboots. */ if (cfg->ec_image.data) tries += 2; /* Find new slot according to target (section) name. */ if (strcmp(target, FMAP_RW_SECTION_A) == 0) slot = FWACT_A; else if (strcmp(target, FMAP_RW_SECTION_B) == 0) slot = FWACT_B; else { ERROR("Unknown target: %s\n", target); return -1; } if (cfg->emulation) { INFO("(emulation) Setting try_next to %s, try_count to %d.\n", slot, tries); return 0; } if (is_vboot2 && VbSetSystemPropertyString("fw_try_next", slot)) { ERROR("Failed to set fw_try_next to %s.\n", slot); return -1; } if (VbSetSystemPropertyInt("fw_try_count", tries)) { ERROR("Failed to set fw_try_count to %d.\n", tries); return -1; } return 0; } /* * Emulates writing to firmware. * Returns 0 if success, non-zero if error. */ static int emulate_write_firmware(const char *filename, const struct firmware_image *image, const char *section_name) { struct firmware_image to_image = {0}; struct firmware_section from, to; int errorcnt = 0; from.data = image->data; from.size = image->size; if (load_firmware_image(&to_image, filename, NULL)) { ERROR("Cannot load image from %s.\n", filename); return -1; } if (section_name) { find_firmware_section(&from, image, section_name); if (!from.data) { ERROR("No section %s in source image %s.\n", section_name, image->file_name); errorcnt++; } find_firmware_section(&to, &to_image, section_name); if (!to.data) { ERROR("No section %s in destination image %s.\n", section_name, filename); errorcnt++; } } else if (image->size != to_image.size) { ERROR("Image size is different (%s:%d != %s:%d)\n", image->file_name, image->size, to_image.file_name, to_image.size); errorcnt++; } else { to.data = to_image.data; to.size = to_image.size; } if (!errorcnt) { size_t to_write = VB2_MIN(to.size, from.size); assert(from.data && to.data); VB2_DEBUG("Writing %zu bytes\n", to_write); memcpy(to.data, from.data, to_write); } if (!errorcnt && vb2_write_file( filename, to_image.data, to_image.size)) { ERROR("Failed writing to file: %s\n", filename); errorcnt++; } free_firmware_image(&to_image); return errorcnt; } /* * Writes a section from given firmware image to system firmware. * If section_name is NULL, write whole image. * Returns 0 if success, non-zero if error. */ static int write_firmware(struct updater_config *cfg, const struct firmware_image *image, const char *section_name) { const char *tmp_file = updater_create_temp_file(cfg); const char *tmp_diff_file = NULL; const char *programmer = image->programmer; char *extra = NULL; int r; if (!tmp_file) return -1; if (cfg->emulation) { INFO("(emulation) Writing %s from %s to %s (emu=%s).\n", section_name ? section_name : "whole image", image->file_name, programmer, cfg->emulation); return emulate_write_firmware( cfg->emulation, image, section_name); } if (vb2_write_file(tmp_file, image->data, image->size) != VB2_SUCCESS) { ERROR("Cannot write temporary file for output: %s\n", tmp_file); return -1; } if (cfg->fast_update && image == &cfg->image && cfg->image_current.data) { tmp_diff_file = updater_create_temp_file(cfg); if (vb2_write_file(tmp_diff_file, cfg->image_current.data, cfg->image_current.size) != VB2_SUCCESS) { ERROR("Cannot write temporary file for diff image\n"); return -1; } ASPRINTF(&extra, "--noverify --diff=%s", tmp_diff_file); } r = host_flashrom(FLASHROM_WRITE, tmp_file, programmer, cfg->verbosity + 1, section_name, extra); free(extra); return r; } /* * Returns True if we should start the update process for given image. */ static int has_valid_update(struct updater_config *cfg, const struct firmware_image *image, const char *section_name, int is_host) { if (!image->data) { VB2_DEBUG("No data in <%s> image.\n", image->programmer); return 0; } if (section_name && !firmware_section_exists(image, section_name)) { VB2_DEBUG("Image %s<%s> does not have section %s.\n", image->file_name, image->programmer, section_name); return 0; } /* Currently only host emulation is supported. */ if (cfg->emulation && !is_host) { INFO("(emulation) Update %s from %s to %s (%d bytes), " "skipped for non-host targets in emulation.\n", section_name ? section_name : "whole image", image->file_name, image->programmer, image->size); return 0; } return 1; } /* * Write a section from given firmware image to system firmware if possible. * If section_name is NULL, write whole image. If the image has no data or if * the section does not exist, ignore and return success. * Returns 0 if success, non-zero if error. */ static int write_optional_firmware(struct updater_config *cfg, const struct firmware_image *image, const char *section_name, int check_programmer_wp, int is_host) { if (!has_valid_update(cfg, image, section_name, is_host)) return 0; /* * EC & PD may have different WP settings and we want to write * only if it is OK. */ if (check_programmer_wp && get_system_property(SYS_PROP_WP_HW, cfg) == WP_ENABLED && host_get_wp(image->programmer) == WP_ENABLED) { ERROR("Target %s is write protected, skip updating.\n", image->programmer); return 0; } return write_firmware(cfg, image, section_name); } /* * Preserves (copies) the given section (by name) from image_from to image_to. * The offset may be different, and the section data will be directly copied. * If the section does not exist on either images, return as failure. * If the source section is larger, contents on destination be truncated. * If the source section is smaller, the remaining area is not modified. * Returns 0 if success, non-zero if error. */ int preserve_firmware_section(const struct firmware_image *image_from, struct firmware_image *image_to, const char *section_name) { struct firmware_section from, to; find_firmware_section(&from, image_from, section_name); find_firmware_section(&to, image_to, section_name); if (!from.data || !to.data) { VB2_DEBUG("Cannot find section %.*s: from=%p, to=%p\n", FMAP_NAMELEN, section_name, from.data, to.data); return -1; } if (from.size > to.size) { WARN("Section %.*s is truncated after updated.\n", FMAP_NAMELEN, section_name); } /* Use memmove in case if we need to deal with sections that overlap. */ memmove(to.data, from.data, VB2_MIN(from.size, to.size)); return 0; } /* * Finds the GBB (Google Binary Block) header on a given firmware image. * Returns a pointer to valid GBB header, or NULL on not found. */ const struct vb2_gbb_header *find_gbb(const struct firmware_image *image) { struct firmware_section section; struct vb2_gbb_header *gbb_header; find_firmware_section(§ion, image, FMAP_RO_GBB); gbb_header = (struct vb2_gbb_header *)section.data; if (!futil_valid_gbb_header(gbb_header, section.size, NULL)) { ERROR("Cannot find GBB in image: %s.\n", image->file_name); return NULL; } return gbb_header; } /* * Preserve the GBB contents from image_from to image_to. * HWID is always preserved, and flags are preserved only if preserve_flags set. * Returns 0 if success, otherwise -1 if GBB header can't be found or if HWID is * too large. */ static int preserve_gbb(const struct firmware_image *image_from, struct firmware_image *image_to, int preserve_flags) { const struct vb2_gbb_header *gbb_from; struct vb2_gbb_header *gbb_to; gbb_from = find_gbb(image_from); /* We do want to change GBB contents later. */ gbb_to = (struct vb2_gbb_header *)find_gbb(image_to); if (!gbb_from || !gbb_to) return -1; /* Preserve flags (for non-factory mode). */ if (preserve_flags) gbb_to->flags = gbb_from->flags; /* Preserve HWID. */ return futil_set_gbb_hwid( gbb_to, (const char *)gbb_from + gbb_from->hwid_offset); } /* * Preserves the regions locked by Intel management engine. */ static int preserve_management_engine(struct updater_config *cfg, const struct firmware_image *image_from, struct firmware_image *image_to) { struct firmware_section section; find_firmware_section(§ion, image_from, FMAP_SI_ME); if (!section.data) { VB2_DEBUG("Skipped because no section %s.\n", FMAP_SI_ME); return 0; } if (section_is_filled_with(§ion, 0xFF)) { VB2_DEBUG("ME is probably locked - preserving %s.\n", FMAP_SI_DESC); return preserve_firmware_section( image_from, image_to, FMAP_SI_DESC); } return try_apply_quirk(QUIRK_UNLOCK_ME_FOR_UPDATE, cfg); } /* Preserve firmware sections by FMAP area flags. */ static int preserve_fmap_sections(struct firmware_image *from, struct firmware_image *to, int *count) { int i, errcnt = 0; FmapHeader *fmap = to->fmap_header; FmapAreaHeader *ah = (FmapAreaHeader*)( (uint8_t *)fmap + sizeof(FmapHeader)); *count = 0; for (i = 0; i < fmap->fmap_nareas; i++, ah++) { if (!(ah->area_flags & FMAP_AREA_PRESERVE)) continue; /* Warning: area_name 'may' not end with NUL. */ if (!firmware_section_exists(from, ah->area_name)) { VB2_DEBUG("FMAP area does not exist in source: %.*s\n", FMAP_NAMELEN, ah->area_name); continue; } VB2_DEBUG("Preserve FMAP area: %.*s\n", FMAP_NAMELEN, ah->area_name); errcnt += preserve_firmware_section(from, to, ah->area_name); (*count)++; } return errcnt; } /* * Preserve old images without "preserve" information in FMAP. * We have to use the legacy hard-coded list of names. */ static int preserve_known_sections(struct firmware_image *from, struct firmware_image *to) { int errcnt = 0, i; const char * const names[] = { "RW_PRESERVE", /* Only octopus fw branch is using this. */ "RO_VPD", "RW_VPD", "SMMSTORE", "RW_NVRAM", "RW_ELOG", }; for (i = 0; i < ARRAY_SIZE(names); i++) { if (!firmware_section_exists(from, names[i])) continue; VB2_DEBUG("Preserve firmware section: %s\n", names[i]); errcnt += preserve_firmware_section(from, to, names[i]); } return errcnt; } /* * Preserves the critical sections from the current (active) firmware. * Currently preserved sections: GBB (HWID and flags), x86 ME, and any firmware * sections with FMAP_AREA_PRESERVE flag set (or a list of known names). * Returns 0 if success, non-zero if error. */ static int preserve_images(struct updater_config *cfg) { int errcnt = 0, found; struct firmware_image *from = &cfg->image_current, *to = &cfg->image; errcnt += preserve_gbb(from, to, !cfg->factory_update); errcnt += preserve_management_engine(cfg, from, to); errcnt += preserve_fmap_sections(from, to, &found); if (!found) errcnt += preserve_known_sections(from, to); return errcnt; } /* * Compares if two sections have same size and data. * Returns 0 if given sections are the same, otherwise non-zero. */ static int compare_section(const struct firmware_section *a, const struct firmware_section *b) { if (a->size != b->size) return a->size - b->size; return memcmp(a->data, b->data, a->size); } /* * Returns if the images are different (should be updated) in given section. * If the section contents are the same or if the section does not exist on both * images, return value is 0 (no need to update). Otherwise the return value is * non-zero, indicating an update should be performed. * If section_name is NULL, compare whole images. */ static int section_needs_update(const struct firmware_image *image_from, const struct firmware_image *image_to, const char *section_name) { struct firmware_section from, to; if (!section_name) { if (image_from->size != image_to->size) return -1; return memcmp(image_from->data, image_to->data, image_to->size); } find_firmware_section(&from, image_from, section_name); find_firmware_section(&to, image_to, section_name); return compare_section(&from, &to); } /* * Returns true if the write protection is enabled on current system. */ static int is_write_protection_enabled(struct updater_config *cfg) { /* Default to enabled. */ int wp = get_system_property(SYS_PROP_WP_HW, cfg); if (wp == WP_DISABLED) return wp; /* For error or enabled, check WP SW. */ wp = get_system_property(SYS_PROP_WP_SW, cfg); /* Consider all errors as enabled. */ if (wp != WP_DISABLED) return WP_ENABLED; return wp; } /* * Checks if the given firmware images are compatible with current platform. * In current implementation (following Chrome OS style), we assume the platform * is identical to the name before a dot (.) in firmware version. * Returns 0 for success, otherwise failure. */ static int check_compatible_platform(struct updater_config *cfg) { int len; struct firmware_image *image_from = &cfg->image_current, *image_to = &cfg->image; const char *from_dot = strchr(image_from->ro_version, '.'), *to_dot = strchr(image_to->ro_version, '.'); if (!from_dot || !to_dot) { VB2_DEBUG("Missing dot (from=%p, to=%p)\n", from_dot, to_dot); return -1; } len = from_dot - image_from->ro_version + 1; VB2_DEBUG("Platform: %*.*s\n", len, len, image_from->ro_version); return strncmp(image_from->ro_version, image_to->ro_version, len); } /* * Returns a valid root key from GBB header, or NULL on failure. */ static const struct vb2_packed_key *get_rootkey( const struct vb2_gbb_header *gbb) { struct vb2_packed_key *key = NULL; key = (struct vb2_packed_key *)((uint8_t *)gbb + gbb->rootkey_offset); if (!packed_key_looks_ok(key, gbb->rootkey_size)) { ERROR("Invalid root key.\n"); return NULL; } return key; } /* * Returns a keyblock key from given image section, or NULL on failure. */ static const struct vb2_keyblock *get_keyblock( const struct firmware_image *image, const char *section_name) { struct firmware_section section; find_firmware_section(§ion, image, section_name); /* A keyblock must be followed by a vb2_fw_preamble. */ if (section.size < sizeof(struct vb2_keyblock) + sizeof(struct vb2_fw_preamble)) { ERROR("Invalid section: %s\n", section_name); return NULL; } return (const struct vb2_keyblock *)section.data; } /* * Duplicates a keyblock and returns the duplicated block. * The caller must free the returned keyblock after being used. */ static struct vb2_keyblock *dupe_keyblock(const struct vb2_keyblock *block) { struct vb2_keyblock *new_block; new_block = (struct vb2_keyblock *)malloc(block->keyblock_size); assert(new_block); memcpy(new_block, block, block->keyblock_size); return new_block; } /* * Verifies if keyblock is signed with given key. * Returns 0 on success, otherwise failure. */ static int verify_keyblock(const struct vb2_keyblock *block, const struct vb2_packed_key *sign_key) { int r; uint8_t workbuf[VB2_FIRMWARE_WORKBUF_RECOMMENDED_SIZE]; struct vb2_workbuf wb; struct vb2_public_key key; struct vb2_keyblock *new_block; if (block->keyblock_signature.sig_size == 0) { ERROR("Keyblock is not signed.\n"); return -1; } vb2_workbuf_init(&wb, workbuf, sizeof(workbuf)); if (VB2_SUCCESS != vb2_unpack_key(&key, sign_key)) { ERROR("Invalid signing key.\n"); return -1; } /* * vb2_verify_keyblock will destroy the signature inside keyblock * so we have to verify with a local copy. */ new_block = dupe_keyblock(block); r = vb2_verify_keyblock(new_block, new_block->keyblock_size, &key, &wb); free(new_block); if (r != VB2_SUCCESS) { ERROR("Failed verifying keyblock.\n"); return -1; } return 0; } /* * Gets the data key and firmware version from a section on firmware image. * The section should contain a vb2_keyblock and a vb2_fw_preamble immediately * after keyblock so we can decode and save the data key and firmware version * into argument `data_key_version` and `firmware_version`. * Returns 0 for success, otherwise failure. */ static int get_key_versions(const struct firmware_image *image, const char *section_name, unsigned int *data_key_version, unsigned int *firmware_version) { const struct vb2_keyblock *keyblock = get_keyblock(image, section_name); const struct vb2_fw_preamble *pre; if (!keyblock) return -1; *data_key_version = keyblock->data_key.key_version; pre = (struct vb2_fw_preamble *)((uint8_t*)keyblock + keyblock->keyblock_size); *firmware_version = pre->firmware_version; VB2_DEBUG("%s: data key version = %d, firmware version = %d\n", image->file_name, *data_key_version, *firmware_version); return 0; } /* * Checks if the root key in ro_image can verify vblocks in rw_image. * Returns 0 for success, otherwise failure. */ static enum rootkey_compat_result check_compatible_root_key( const struct firmware_image *ro_image, const struct firmware_image *rw_image) { const struct vb2_gbb_header *gbb = find_gbb(ro_image); const struct vb2_packed_key *rootkey; const struct vb2_keyblock *keyblock; if (!gbb) return ROOTKEY_COMPAT_ERROR; rootkey = get_rootkey(gbb); if (!rootkey) return ROOTKEY_COMPAT_ERROR; /* Assume VBLOCK_A and VBLOCK_B are signed in same way. */ keyblock = get_keyblock(rw_image, FMAP_RW_VBLOCK_A); if (!keyblock) return ROOTKEY_COMPAT_ERROR; if (verify_keyblock(keyblock, rootkey) != 0) { const struct vb2_gbb_header *gbb_rw = find_gbb(rw_image); const struct vb2_packed_key *rootkey_rw = NULL; int is_same_key = 0, to_dev = 0; /* * Try harder to provide more info. * packed_key_sha1_string uses static buffer so don't call * it twice in args list of one expression. */ if (gbb_rw) rootkey_rw = get_rootkey(gbb_rw); if (rootkey_rw) { if (rootkey->key_offset == rootkey_rw->key_offset && rootkey->key_size == rootkey_rw->key_size && memcmp(rootkey, rootkey_rw, rootkey->key_size + rootkey->key_offset) == 0) is_same_key = 1; if (strcmp(packed_key_sha1_string(rootkey_rw), ROOTKEY_HASH_DEV) == 0) to_dev = 1; } INFO("Current (RO) firmware image has root key: %s\n", packed_key_sha1_string(rootkey)); if (is_same_key) { ERROR("Rootkey is same as target (RW) image. \n" "Maybe RW corrupted?"); return ROOTKEY_COMPAT_ERROR; } WARN("Target (RW) image is signed by root key: %s%s\n", rootkey_rw ? packed_key_sha1_string(rootkey_rw) : "", to_dev ? " (DEV/unsigned)" : ""); return to_dev ? ROOTKEY_COMPAT_REKEY_TO_DEV : ROOTKEY_COMPAT_REKEY; } return ROOTKEY_COMPAT_OK; } /* * Returns 1 if a given file (cbfs_entry_name) exists inside a particular CBFS * section of an image file, otherwise 0. */ static int cbfs_file_exists(const char *image_file, const char *section_name, const char *cbfs_entry_name) { char *cmd; int r; ASPRINTF(&cmd, "cbfstool '%s' print -r %s 2>/dev/null | grep -q '^%s '", image_file, section_name, cbfs_entry_name); r = system(cmd); free(cmd); return !r; } static int cbfs_extract_file(const char *image_file, const char *section_name, const char *cbfs_entry_name, const char *output_name) { char *cmd; int r; ASPRINTF(&cmd, "cbfstool '%s' extract -r %s -n '%s' -f '%s' " "2>/dev/null", image_file, section_name, cbfs_entry_name, output_name); r = system(cmd); free(cmd); return r; } /* * Returns non-zero if the RW_LEGACY needs to be updated, otherwise 0. */ static int legacy_needs_update(struct updater_config *cfg) { int has_from, has_to; const char * const tag = "cros_allow_auto_update"; const char *section = FMAP_RW_LEGACY; const char *tmp_path = updater_create_temp_file(cfg); VB2_DEBUG("Checking %s contents...\n", FMAP_RW_LEGACY); if (!tmp_path || vb2_write_file(tmp_path, cfg->image.data, cfg->image.size)) { ERROR("Failed to create temporary file for image contents.\n"); return 0; } has_to = cbfs_file_exists(tmp_path, section, tag); has_from = cbfs_file_exists(tmp_path, section, tag); if (!has_from || !has_to) { VB2_DEBUG("Current legacy firmware has%s updater tag (%s) and " "target firmware has%s updater tag, won't update.\n", has_from ? "" : " no", tag, has_to ? "" : " no"); return 0; } return section_needs_update( &cfg->image_current, &cfg->image, FMAP_RW_LEGACY); } /* * Checks if the given firmware image is signed with a key that won't be * blocked by TPM's anti-rollback detection. * Returns 0 for success, otherwise failure. */ static int do_check_compatible_tpm_keys(struct updater_config *cfg, const struct firmware_image *rw_image) { unsigned int data_key_version = 0, firmware_version = 0, tpm_data_key_version = 0, tpm_firmware_version = 0; int tpm_fwver = 0; /* Fail if the given image does not look good. */ if (get_key_versions(rw_image, FMAP_RW_VBLOCK_A, &data_key_version, &firmware_version) != 0) return -1; /* The stored tpm_fwver can be 0 (b/116298359#comment3). */ tpm_fwver = get_system_property(SYS_PROP_TPM_FWVER, cfg); if (tpm_fwver < 0) { ERROR("Invalid tpm_fwver: %d.\n", tpm_fwver); return -1; } tpm_data_key_version = tpm_fwver >> 16; tpm_firmware_version = tpm_fwver & 0xffff; VB2_DEBUG("TPM: data_key_version = %d, firmware_version = %d\n", tpm_data_key_version, tpm_firmware_version); if (tpm_data_key_version > data_key_version) { ERROR("Data key version rollback detected (%d->%d).\n", tpm_data_key_version, data_key_version); return -1; } if (tpm_firmware_version > firmware_version) { ERROR("Firmware version rollback detected (%d->%d).\n", tpm_firmware_version, firmware_version); return -1; } return 0; } /* * Wrapper for do_check_compatible_tpm_keys. * Will return 0 if do_check_compatible_tpm_keys success or if cfg.force_update * is set; otherwise non-zero. */ static int check_compatible_tpm_keys(struct updater_config *cfg, const struct firmware_image *rw_image) { int r = do_check_compatible_tpm_keys(cfg, rw_image); if (!r) return r; if (!cfg->force_update) { ERROR("Add --force if you want to waive TPM checks.\n"); return r; } WARN("TPM KEYS CHECK IS WAIVED BY --force. YOU ARE ON YOUR OWN.\n"); return 0; } /* * Returns True if the system has EC software sync enabled. */ static int is_ec_software_sync_enabled(struct updater_config *cfg) { const struct vb2_gbb_header *gbb; /* Check if current system has disabled software sync or no support. */ if (!(VbGetSystemPropertyInt("vdat_flags") & VBSD_EC_SOFTWARE_SYNC)) { INFO("EC Software Sync is not available.\n"); return 0; } /* Check if the system has been updated to disable software sync. */ gbb = find_gbb(&cfg->image); if (!gbb) { WARN("Invalid AP firmware image.\n"); return 0; } if (gbb->flags & VB2_GBB_FLAG_DISABLE_EC_SOFTWARE_SYNC) { INFO("EC Software Sync will be disabled in next boot.\n"); return 0; } return 1; } /* * Schedules an EC RO software sync (in next boot) if applicable. */ static int ec_ro_software_sync(struct updater_config *cfg) { const char *tmp_path = updater_create_temp_file(cfg); const char *ec_ro_path = updater_create_temp_file(cfg); uint8_t *ec_ro_data; uint32_t ec_ro_len; int is_same_ec_ro; struct firmware_section ec_ro_sec; if (!tmp_path || !ec_ro_path || vb2_write_file(tmp_path, cfg->image.data, cfg->image.size)) { ERROR("Failed to create temporary file for image contents.\n"); return 1; } find_firmware_section(&ec_ro_sec, &cfg->ec_image, "EC_RO"); if (!ec_ro_sec.data || !ec_ro_sec.size) { ERROR("EC image has invalid section '%s'.\n", "EC_RO"); return 1; } if (cbfs_extract_file(tmp_path, FMAP_RO_SECTION, "ec_ro", ec_ro_path) || !cbfs_file_exists(tmp_path, FMAP_RO_SECTION, "ec_ro.hash")) { INFO("No valid EC RO for software sync in AP firmware.\n"); return 1; } if (vb2_read_file(ec_ro_path, &ec_ro_data, &ec_ro_len) != VB2_SUCCESS) { ERROR("Failed to read EC RO.\n"); return 1; } is_same_ec_ro = (ec_ro_len <= ec_ro_sec.size && memcmp(ec_ro_sec.data, ec_ro_data, ec_ro_len) == 0); free(ec_ro_data); if (!is_same_ec_ro) { /* TODO(hungte) If change AP RO is not a problem (hash will be * different, which may be a problem to factory and HWID), or if * we can be be sure this is for developers, extract EC RO and * update AP RO CBFS to trigger EC RO sync with new EC. */ ERROR("The EC RO contents specified from AP (--image) and EC " "(--ec_image) firmware images are different, cannot " "update by EC RO software sync.\n"); return 1; } VbSetSystemPropertyInt("try_ro_sync", 1); return 0; } /* * Returns True if EC is running in RW. */ static int is_ec_in_rw(void) { char buf[VB_MAX_STRING_PROPERTY]; return (VbGetSystemPropertyString("ecfw_act", buf, sizeof(buf)) && strcasecmp(buf, "RW") == 0); } /* * Update EC (RO+RW) in most reliable way. * * Some EC will reset TCPC when doing sysjump, and will make rootfs unavailable * if the system was boot from USB, or other unexpected issues even if the * system was boot from internal disk. To prevent that, try to partial update * only RO and expect EC software sync to update RW later, or perform EC RO * software sync. * * Returns 0 if success, non-zero if error. */ static int update_ec_firmware(struct updater_config *cfg) { const char *ec_ro = "EC_RO"; struct firmware_image *ec_image = &cfg->ec_image; /* TODO(hungte) Check if we have EC RO in AP image without --ec_image */ if (!has_valid_update(cfg, ec_image, NULL, 0)) return 0; if (!firmware_section_exists(ec_image, ec_ro)) { INFO("EC image does not have section '%s'.\n", ec_ro); } else if (!is_ec_software_sync_enabled(cfg)) { /* Message already printed. */ } else if (is_ec_in_rw()) { WARN("EC Software Sync detected, will only update EC RO. " "The contents in EC RW will be updated after reboot.\n"); return write_optional_firmware(cfg, ec_image, ec_ro, 1, 0); } else if (ec_ro_software_sync(cfg) == 0) { INFO("EC RO and RW should be updated after reboot.\n"); return 0; } /* Do full update. */ WARN("Update EC RO+RW and may cause unexpected error later. " "See http://crbug.com/782427#c4 for more information.\n"); return write_optional_firmware(cfg, ec_image, NULL, 1, 0); } const char * const updater_error_messages[] = { [UPDATE_ERR_DONE] = "Done (no error)", [UPDATE_ERR_NEED_RO_UPDATE] = "RO changed and no WP. Need full update.", [UPDATE_ERR_NO_IMAGE] = "No image to update; try specify with -i.", [UPDATE_ERR_SYSTEM_IMAGE] = "Cannot load system active firmware.", [UPDATE_ERR_INVALID_IMAGE] = "The given firmware image is not valid.", [UPDATE_ERR_SET_COOKIES] = "Failed writing system flags to try update.", [UPDATE_ERR_WRITE_FIRMWARE] = "Failed writing firmware.", [UPDATE_ERR_PLATFORM] = "Your system platform is not compatible.", [UPDATE_ERR_TARGET] = "No valid RW target to update. Abort.", [UPDATE_ERR_ROOT_KEY] = "RW signed by incompatible root key " "(different from RO).", [UPDATE_ERR_TPM_ROLLBACK] = "RW not usable due to TPM anti-rollback.", [UPDATE_ERR_UNKNOWN] = "Unknown error.", }; /* * The main updater for "Try-RW update", to update only one RW section * and try if it can boot properly on reboot. * This was also known as --mode=autoupdate,--wp=1 in legacy updater. * Returns UPDATE_ERR_DONE if success, otherwise error. */ static enum updater_error_codes update_try_rw_firmware( struct updater_config *cfg, struct firmware_image *image_from, struct firmware_image *image_to, int wp_enabled) { const char *target; int has_update = 1; int is_vboot2 = get_system_property(SYS_PROP_FW_VBOOT2, cfg); preserve_gbb(image_from, image_to, 1); if (!wp_enabled && section_needs_update( image_from, image_to, FMAP_RO_SECTION)) return UPDATE_ERR_NEED_RO_UPDATE; INFO("Checking compatibility...\n"); if (check_compatible_root_key(image_from, image_to)) return UPDATE_ERR_ROOT_KEY; if (check_compatible_tpm_keys(cfg, image_to)) return UPDATE_ERR_TPM_ROLLBACK; VB2_DEBUG("Firmware %s vboot2.\n", is_vboot2 ? "is" : "is NOT"); target = decide_rw_target(cfg, TARGET_SELF, is_vboot2); if (target == NULL) { ERROR("TRY-RW update needs system to boot in RW firmware.\n"); return UPDATE_ERR_TARGET; } INFO("Checking %s contents...\n", target); if (!firmware_section_exists(image_to, target)) { ERROR("Cannot find section '%s' on firmware image: %s\n", target, image_to->file_name); return UPDATE_ERR_INVALID_IMAGE; } if (!cfg->force_update) has_update = section_needs_update(image_from, image_to, target); if (has_update) { target = decide_rw_target(cfg, TARGET_UPDATE, is_vboot2); STATUS("TRY-RW UPDATE: Updating %s to try on reboot.\n", target); if (write_firmware(cfg, image_to, target)) return UPDATE_ERR_WRITE_FIRMWARE; if (set_try_cookies(cfg, target, is_vboot2)) return UPDATE_ERR_SET_COOKIES; } else { /* Clear trial cookies for vboot1. */ if (!is_vboot2 && !cfg->emulation) VbSetSystemPropertyInt("fwb_tries", 0); } /* Do not fail on updating legacy. */ if (legacy_needs_update(cfg)) { has_update = 1; STATUS("LEGACY UPDATE: Updating %s.\n", FMAP_RW_LEGACY); write_firmware(cfg, image_to, FMAP_RW_LEGACY); } if (!has_update) STATUS("NO UPDATE: No need to update.\n"); return UPDATE_ERR_DONE; } /* * The main updater for "RW update". * This was also known as --mode=recovery, --wp=1 in legacy updater. * Returns UPDATE_ERR_DONE if success, otherwise error. */ static enum updater_error_codes update_rw_firmware( struct updater_config *cfg, struct firmware_image *image_from, struct firmware_image *image_to) { STATUS("RW UPDATE: Updating RW sections (%s, %s, %s, and %s).\n", FMAP_RW_SECTION_A, FMAP_RW_SECTION_B, FMAP_RW_SHARED, FMAP_RW_LEGACY); INFO("Checking compatibility...\n"); if (check_compatible_root_key(image_from, image_to)) return UPDATE_ERR_ROOT_KEY; if (check_compatible_tpm_keys(cfg, image_to)) return UPDATE_ERR_TPM_ROLLBACK; /* * TODO(hungte) Speed up by flashing multiple sections in one * command, or provide diff file. */ if (write_firmware(cfg, image_to, FMAP_RW_SECTION_A) || write_firmware(cfg, image_to, FMAP_RW_SECTION_B) || write_firmware(cfg, image_to, FMAP_RW_SHARED) || write_optional_firmware(cfg, image_to, FMAP_RW_LEGACY, 0, 1)) return UPDATE_ERR_WRITE_FIRMWARE; return UPDATE_ERR_DONE; } /* * The main updater for "Legacy update". * This is equivalent to --mode=legacy. * Returns UPDATE_ERR_DONE if success, otherwise error. */ static enum updater_error_codes update_legacy_firmware( struct updater_config *cfg, struct firmware_image *image_to) { STATUS("LEGACY UPDATE: Updating firmware %s.\n", FMAP_RW_LEGACY); if (write_firmware(cfg, image_to, FMAP_RW_LEGACY)) return UPDATE_ERR_WRITE_FIRMWARE; return UPDATE_ERR_DONE; } /* * The main updater for "Full update". * This was also known as "--mode=factory" or "--mode=recovery, --wp=0" in * legacy updater. * Returns UPDATE_ERR_DONE if success, otherwise error. */ static enum updater_error_codes update_whole_firmware( struct updater_config *cfg, struct firmware_image *image_to) { STATUS("FULL UPDATE: Updating whole firmware image(s), RO+RW.\n"); if (preserve_images(cfg)) VB2_DEBUG("Failed to preserve some sections - ignore.\n"); INFO("Checking compatibility...\n"); if (!cfg->force_update) { /* Check if the image_to itself is broken */ enum rootkey_compat_result r = check_compatible_root_key( image_to, image_to); if (r != ROOTKEY_COMPAT_OK) { ERROR("Target image does not look valid. \n" "Add --force if you really want to use it."); return UPDATE_ERR_ROOT_KEY; } /* Check if the system is going to re-key. */ r = check_compatible_root_key(&cfg->image_current, image_to); /* We only allow re-key to non-dev keys. */ switch (r) { case ROOTKEY_COMPAT_OK: break; case ROOTKEY_COMPAT_REKEY: INFO("Will change firmware signing key.\n"); break; case ROOTKEY_COMPAT_REKEY_TO_DEV: ERROR("Re-key to DEV is not allowed. \n" "Add --force if you really want to do that."); return UPDATE_ERR_ROOT_KEY; default: return UPDATE_ERR_ROOT_KEY; } } if (check_compatible_tpm_keys(cfg, image_to)) return UPDATE_ERR_TPM_ROLLBACK; /* FMAP may be different so we should just update all. */ if (write_firmware(cfg, image_to, NULL) || update_ec_firmware(cfg) || write_optional_firmware(cfg, &cfg->pd_image, NULL, 1, 0)) return UPDATE_ERR_WRITE_FIRMWARE; return UPDATE_ERR_DONE; } /* * The main updater to update system firmware using the configuration parameter. * Returns UPDATE_ERR_DONE if success, otherwise failure. */ enum updater_error_codes update_firmware(struct updater_config *cfg) { int wp_enabled, done = 0; enum updater_error_codes r = UPDATE_ERR_UNKNOWN; struct firmware_image *image_from = &cfg->image_current, *image_to = &cfg->image; if (!image_to->data) return UPDATE_ERR_NO_IMAGE; if (try_apply_quirk(QUIRK_DAISY_SNOW_DUAL_MODEL, cfg)) return UPDATE_ERR_PLATFORM; STATUS("Target image: %s (RO:%s, RW/A:%s, RW/B:%s).\n", image_to->file_name, image_to->ro_version, image_to->rw_version_a, image_to->rw_version_b); if (try_apply_quirk(QUIRK_MIN_PLATFORM_VERSION, cfg)) return UPDATE_ERR_PLATFORM; if (!image_from->data) { /* * TODO(hungte) Read only RO_SECTION, VBLOCK_A, VBLOCK_B, * RO_VPD, RW_VPD, RW_NVRAM, RW_LEGACY. */ INFO("Loading current system firmware...\n"); if (load_system_firmware(cfg, image_from) != 0) return UPDATE_ERR_SYSTEM_IMAGE; } STATUS("Current system: %s (RO:%s, RW/A:%s, RW/B:%s).\n", image_from->file_name, image_from->ro_version, image_from->rw_version_a, image_from->rw_version_b); if (cfg->check_platform && check_compatible_platform(cfg)) return UPDATE_ERR_PLATFORM; wp_enabled = is_write_protection_enabled(cfg); STATUS("Write protection: %d (%s; HW=%d, SW=%d).\n", wp_enabled, wp_enabled ? "enabled" : "disabled", get_system_property(SYS_PROP_WP_HW, cfg), get_system_property(SYS_PROP_WP_SW, cfg)); if (try_apply_quirk(QUIRK_ENLARGE_IMAGE, cfg)) return UPDATE_ERR_SYSTEM_IMAGE; if (try_apply_quirk(QUIRK_EVE_SMM_STORE, cfg)) return UPDATE_ERR_INVALID_IMAGE; if (debugging_enabled) print_system_properties(cfg); if (cfg->legacy_update) return update_legacy_firmware(cfg, image_to); if (cfg->try_update) { r = update_try_rw_firmware(cfg, image_from, image_to, wp_enabled); if (r == UPDATE_ERR_NEED_RO_UPDATE) WARN("%s\n", updater_error_messages[r]); else done = 1; } if (!done) { r = wp_enabled ? update_rw_firmware(cfg, image_from, image_to) : update_whole_firmware(cfg, image_to); } /* Providing more hints for what to do on failure. */ if (r == UPDATE_ERR_ROOT_KEY && wp_enabled) ERROR("To change keys in RO area, you must first remove " "write protection ( " REMOVE_WP_URL " ).\n"); return r; } /* * Allocates and initializes a updater_config object with default values. * Returns the newly allocated object, or NULL on error. */ struct updater_config *updater_new_config() { struct system_property *props; struct updater_config *cfg = (struct updater_config *)calloc( 1, sizeof(struct updater_config)); if (!cfg) return cfg; cfg->image.programmer = PROG_HOST; cfg->image_current.programmer = PROG_HOST; cfg->ec_image.programmer = PROG_EC; cfg->pd_image.programmer = PROG_PD; cfg->check_platform = 1; props = cfg->system_properties; props[SYS_PROP_MAINFW_ACT].getter = host_get_mainfw_act; props[SYS_PROP_TPM_FWVER].getter = host_get_tpm_fwver; props[SYS_PROP_FW_VBOOT2].getter = host_get_fw_vboot2; props[SYS_PROP_PLATFORM_VER].getter = host_get_platform_version; props[SYS_PROP_WP_HW].getter = host_get_wp_hw; props[SYS_PROP_WP_SW].getter = host_get_wp_sw; updater_register_quirks(cfg); return cfg; } /* * Saves everything from stdin to given output file. * Returns 0 on success, otherwise failure. */ static int save_from_stdin(const char *output) { FILE *in = stdin, *out = fopen(output, "wb"); char buffer[4096]; size_t sz; assert(in); if (!out) return -1; while (!feof(in)) { sz = fread(buffer, 1, sizeof(buffer), in); if (fwrite(buffer, 1, sz, out) != sz) { fclose(out); return -1; } } fclose(out); return 0; } /* * Setup quirks for updating current image. * * Quirks must be loaded after image loaded because we use image contents to * decide default quirks to load. Also, we have to load default quirks first so * user can override them using command line. * * Returns 0 on success, otherwise number of failures. */ static int updater_setup_quirks(struct updater_config *cfg, const struct updater_config_arguments *arg) { int errorcnt = 0; const char *quirks = updater_get_default_quirks(cfg); if (quirks) errorcnt += !!setup_config_quirks(quirks, cfg); if (arg->quirks) errorcnt += !!setup_config_quirks(arg->quirks, cfg); return errorcnt; } /* * Loads images into updater configuration. * Returns 0 on success, otherwise number of failures. */ static int updater_load_images(struct updater_config *cfg, const struct updater_config_arguments *arg, const char *image, const char *ec_image, const char *pd_image) { int errorcnt = 0; struct archive *ar = cfg->archive; if (!cfg->image.data && image) { if (image && strcmp(image, "-") == 0) { INFO("Reading image from stdin...\n"); image = updater_create_temp_file(cfg); if (image) errorcnt += !!save_from_stdin(image); } errorcnt += !!load_firmware_image(&cfg->image, image, ar); if (!errorcnt) errorcnt += updater_setup_quirks(cfg, arg); } if (arg->host_only) return errorcnt; if (!cfg->ec_image.data && ec_image) errorcnt += !!load_firmware_image(&cfg->ec_image, ec_image, ar); if (!cfg->pd_image.data && pd_image) errorcnt += !!load_firmware_image(&cfg->pd_image, pd_image, ar); return errorcnt; } /* * Writes a firmware image to specified file. * Returns 0 on success, otherwise failure. */ static int updater_output_image(const struct firmware_image *image, const char *fname, const char *root) { int r = 0; char *fpath; if (!image->data) return 0; ASPRINTF(&fpath, "%s/%s", root, fname); r = vb2_write_file(fpath, image->data, image->size); if (r) ERROR("Failed writing firmware image to: %s\n", fpath); else printf("Firmware image saved in: %s\n", fpath); free(fpath); return !!r; } /* * Applies white label information to an existing model config. * Returns 0 on success, otherwise failure. */ static int updater_apply_white_label(struct updater_config *cfg, struct model_config *model, const char *signature_id) { const char *tmp_image = NULL; assert(model->is_white_label); if (!signature_id) { if (cfg->image_current.data) { tmp_image = updater_create_temp_file(cfg); if (!tmp_image) return 1; if (vb2_write_file(tmp_image, cfg->image_current.data, cfg->image_current.size)) { ERROR("Failed writing temporary image file.\n"); return 1; } } else { INFO("Loading system firmware for white label...\n"); load_system_firmware(cfg, &cfg->image_current); tmp_image = cfg->image_current.file_name; } if (!tmp_image) { ERROR("Failed to get system current firmware\n"); return 1; } } return !!model_apply_white_label( model, cfg->archive, signature_id, tmp_image); } /* * Setup what the updater has to do against an archive. * Returns number of failures, or 0 on success. */ static int updater_setup_archive( struct updater_config *cfg, const struct updater_config_arguments *arg, struct manifest *manifest, int is_factory) { int errorcnt = 0; struct archive *ar = cfg->archive; const struct model_config *model; if (arg->do_manifest) { assert(!arg->image); print_json_manifest(manifest); /* No additional error. */ return errorcnt; } model = manifest_find_model(manifest, arg->model); if (!model) return ++errorcnt; /* Load images now so we can get quirks in WL checks. */ errorcnt += updater_load_images( cfg, arg, model->image, model->ec_image, model->pd_image); if (model->is_white_label && !manifest->has_keyset) { /* * Developers running unsigned updaters (usually local build) * won't be able match any white label tags. */ WARN("No keysets found - this is probably a local build of \n" "unsigned firmware updater. Skip applying white label."); } else if (model->is_white_label) { /* * It is fine to fail in updater_apply_white_label for factory * mode so we are not checking the return value; instead we * verify if the patches do contain new root key. */ updater_apply_white_label(cfg, (struct model_config *)model, arg->signature_id); if (!model->patches.rootkey) { if (is_factory || is_write_protection_enabled(cfg) || get_config_quirk(QUIRK_ALLOW_EMPTY_WLTAG, cfg)) { WARN("No VPD for white label.\n"); } else { ERROR("Need VPD set for white label.\n"); return ++errorcnt; } } } errorcnt += patch_image_by_model(&cfg->image, model, ar); return errorcnt; } /* * Helper function to setup an allocated updater_config object. * Returns number of failures, or 0 on success. */ int updater_setup_config(struct updater_config *cfg, const struct updater_config_arguments *arg, int *do_update) { int errorcnt = 0; int check_single_image = 0, check_wp_disabled = 0; int do_output = 0; const char *archive_path = arg->archive; /* Setup values that may change output or decision of other argument. */ cfg->verbosity = arg->verbosity; cfg->fast_update = arg->fast_update; cfg->factory_update = arg->is_factory; if (arg->force_update) cfg->force_update = 1; /* Check incompatible options and return early. */ if (arg->do_manifest) { if (!!arg->archive == !!arg->image) { ERROR("--manifest needs either -a or -i\n"); return ++errorcnt; } if (arg->archive && (arg->ec_image || arg->pd_image)) { ERROR("--manifest for archive (-a) does not accept \n" "additional images (--ec_image, --pd_image)."); return ++errorcnt; } *do_update = 0; } if (arg->repack || arg->unpack) { if (!arg->archive) { ERROR("--{re,un}pack needs --archive.\n"); return ++errorcnt; } *do_update = 0; } /* Setup update mode. */ if (arg->try_update) cfg->try_update = 1; if (arg->mode) { if (strcmp(arg->mode, "autoupdate") == 0) { cfg->try_update = 1; } else if (strcmp(arg->mode, "recovery") == 0) { cfg->try_update = 0; } else if (strcmp(arg->mode, "legacy") == 0) { cfg->legacy_update = 1; } else if (strcmp(arg->mode, "factory") == 0 || strcmp(arg->mode, "factory_install") == 0) { cfg->factory_update = 1; } else if (strcmp(arg->mode, "output") == 0) { do_output = 1; } else { errorcnt++; ERROR("Invalid mode: %s\n", arg->mode); } } if (cfg->factory_update) { /* factory_update must be processed after arg->mode. */ check_wp_disabled = 1; cfg->try_update = 0; } /* Setup properties and fields that do not have external dependency. */ if (arg->programmer) { check_single_image = 1; cfg->image.programmer = arg->programmer; cfg->image_current.programmer = arg->programmer; VB2_DEBUG("AP (host) programmer changed to %s.\n", arg->programmer); } if (arg->sys_props) override_properties_from_list(arg->sys_props, cfg); if (arg->write_protection) { /* arg->write_protection must be done after arg->sys_props. */ int r = strtol(arg->write_protection, NULL, 0); override_system_property(SYS_PROP_WP_HW, cfg, r); override_system_property(SYS_PROP_WP_SW, cfg, r); } /* Set up archive and load images. */ if (arg->emulation) { /* Process emulation file first. */ cfg->emulation = arg->emulation; VB2_DEBUG("Using file %s for emulation.\n", arg->emulation); errorcnt += !!load_firmware_image( &cfg->image_current, arg->emulation, NULL); } /* Always load images specified from command line directly. */ errorcnt += updater_load_images( cfg, arg, arg->image, arg->ec_image, arg->pd_image); if (!archive_path) archive_path = "."; cfg->archive = archive_open(archive_path); if (!cfg->archive) { ERROR("Failed to open archive: %s\n", archive_path); return ++errorcnt; } /* Process archives which may not have valid contents. */ if (arg->repack || arg->unpack) { const char *work_name = arg->repack ? arg->repack : arg->unpack; struct archive *from, *to, *work; work = archive_open(work_name); if (arg->repack) { from = work; to = cfg->archive; } else { to = work; from = cfg->archive; } if (!work) { ERROR("Failed to open: %s\n", work_name); return ++errorcnt; } errorcnt += !!archive_copy(from, to); /* TODO(hungte) Update manifest after copied. */ archive_close(work); return errorcnt; } /* Load images from archive. */ if (arg->archive) { struct manifest *m = new_manifest_from_archive(cfg->archive); if (m) { errorcnt += updater_setup_archive( cfg, arg, m, cfg->factory_update); delete_manifest(m); } else { ERROR("Failure in archive: %s\n", arg->archive); ++errorcnt; } } else if (arg->do_manifest) { char name[] = "default"; struct model_config model = { .name = name, .image = arg->image, .ec_image = arg->ec_image, .pd_image = arg->pd_image, }; struct manifest manifest = { .num = 1, .models = &model, }; assert(model.image); print_json_manifest(&manifest); } /* * Images should be loaded now (either in first updater_load_images or * second call from updater_setup_archive) and quirks should be loaded. * For invocation without image, we want to get quirks now. */ if (!cfg->image.data && arg->quirks) errorcnt += !!setup_config_quirks(arg->quirks, cfg); /* Additional checks. */ if (check_single_image && (cfg->ec_image.data || cfg->pd_image.data)) { errorcnt++; ERROR("EC/PD images are not supported in current mode.\n"); } if (check_wp_disabled && is_write_protection_enabled(cfg)) { errorcnt++; ERROR("Please remove write protection for factory mode \n" "( " REMOVE_WP_URL " )."); } if (!errorcnt && do_output) { const char *r = arg->output_dir; if (!r) r = "."; /* TODO(hungte) Remove bios.bin when migration is done. */ errorcnt += updater_output_image(&cfg->image, "bios.bin", r); errorcnt += updater_output_image(&cfg->image, "image.bin", r); errorcnt += updater_output_image(&cfg->ec_image, "ec.bin", r); errorcnt += updater_output_image(&cfg->pd_image, "pd.bin", r); *do_update = 0; } return errorcnt; } /* * Releases all resources in an updater configuration object. */ void updater_delete_config(struct updater_config *cfg) { assert(cfg); free_firmware_image(&cfg->image); free_firmware_image(&cfg->image_current); free_firmware_image(&cfg->ec_image); free_firmware_image(&cfg->pd_image); updater_remove_all_temp_files(cfg); if (cfg->archive) archive_close(cfg->archive); free(cfg); }