diff options
Diffstat (limited to 'src/shared/bootspec.c')
-rw-r--r-- | src/shared/bootspec.c | 665 |
1 files changed, 665 insertions, 0 deletions
diff --git a/src/shared/bootspec.c b/src/shared/bootspec.c new file mode 100644 index 0000000..7e276f1 --- /dev/null +++ b/src/shared/bootspec.c @@ -0,0 +1,665 @@ +/* SPDX-License-Identifier: LGPL-2.1+ */ + +#include <stdio.h> +#include <linux/magic.h> + +#include "sd-id128.h" + +#include "alloc-util.h" +#include "blkid-util.h" +#include "bootspec.h" +#include "conf-files.h" +#include "def.h" +#include "device-nodes.h" +#include "efivars.h" +#include "env-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "parse-util.h" +#include "path-util.h" +#include "stat-util.h" +#include "string-util.h" +#include "strv.h" +#include "virt.h" + +static void boot_entry_free(BootEntry *entry) { + assert(entry); + + free(entry->id); + free(entry->path); + free(entry->title); + free(entry->show_title); + free(entry->version); + free(entry->machine_id); + free(entry->architecture); + strv_free(entry->options); + free(entry->kernel); + free(entry->efi); + strv_free(entry->initrd); + free(entry->device_tree); +} + +static int boot_entry_load(const char *path, BootEntry *entry) { + _cleanup_(boot_entry_free) BootEntry tmp = {}; + _cleanup_fclose_ FILE *f = NULL; + unsigned line = 1; + char *b, *c; + int r; + + assert(path); + assert(entry); + + c = endswith_no_case(path, ".conf"); + if (!c) { + log_error("Invalid loader entry filename: %s", path); + return -EINVAL; + } + + b = basename(path); + tmp.id = strndup(b, c - b); + if (!tmp.id) + return log_oom(); + + tmp.path = strdup(path); + if (!tmp.path) + return log_oom(); + + f = fopen(path, "re"); + if (!f) + return log_error_errno(errno, "Failed to open \"%s\": %m", path); + + for (;;) { + _cleanup_free_ char *buf = NULL, *field = NULL; + const char *p; + + r = read_line(f, LONG_LINE_MAX, &buf); + if (r == 0) + break; + if (r == -ENOBUFS) + return log_error_errno(r, "%s:%u: Line too long", path, line); + if (r < 0) + return log_error_errno(r, "%s:%u: Error while reading: %m", path, line); + + line++; + + if (IN_SET(*strstrip(buf), '#', '\0')) + continue; + + p = buf; + r = extract_first_word(&p, &field, " \t", 0); + if (r < 0) { + log_error_errno(r, "Failed to parse config file %s line %u: %m", path, line); + continue; + } + if (r == 0) { + log_warning("%s:%u: Bad syntax", path, line); + continue; + } + + if (streq(field, "title")) + r = free_and_strdup(&tmp.title, p); + else if (streq(field, "version")) + r = free_and_strdup(&tmp.version, p); + else if (streq(field, "machine-id")) + r = free_and_strdup(&tmp.machine_id, p); + else if (streq(field, "architecture")) + r = free_and_strdup(&tmp.architecture, p); + else if (streq(field, "options")) + r = strv_extend(&tmp.options, p); + else if (streq(field, "linux")) + r = free_and_strdup(&tmp.kernel, p); + else if (streq(field, "efi")) + r = free_and_strdup(&tmp.efi, p); + else if (streq(field, "initrd")) + r = strv_extend(&tmp.initrd, p); + else if (streq(field, "devicetree")) + r = free_and_strdup(&tmp.device_tree, p); + else { + log_notice("%s:%u: Unknown line \"%s\"", path, line, field); + continue; + } + if (r < 0) + return log_error_errno(r, "%s:%u: Error while reading: %m", path, line); + } + + *entry = tmp; + tmp = (BootEntry) {}; + return 0; +} + +void boot_config_free(BootConfig *config) { + size_t i; + + assert(config); + + free(config->default_pattern); + free(config->timeout); + free(config->editor); + free(config->auto_entries); + free(config->auto_firmware); + + free(config->entry_oneshot); + free(config->entry_default); + + for (i = 0; i < config->n_entries; i++) + boot_entry_free(config->entries + i); + free(config->entries); +} + +static int boot_loader_read_conf(const char *path, BootConfig *config) { + _cleanup_fclose_ FILE *f = NULL; + unsigned line = 1; + int r; + + assert(path); + assert(config); + + f = fopen(path, "re"); + if (!f) { + if (errno == ENOENT) + return 0; + + return log_error_errno(errno, "Failed to open \"%s\": %m", path); + } + + for (;;) { + _cleanup_free_ char *buf = NULL, *field = NULL; + const char *p; + + r = read_line(f, LONG_LINE_MAX, &buf); + if (r == 0) + break; + if (r == -ENOBUFS) + return log_error_errno(r, "%s:%u: Line too long", path, line); + if (r < 0) + return log_error_errno(r, "%s:%u: Error while reading: %m", path, line); + + line++; + + if (IN_SET(*strstrip(buf), '#', '\0')) + continue; + + p = buf; + r = extract_first_word(&p, &field, " \t", 0); + if (r < 0) { + log_error_errno(r, "Failed to parse config file %s line %u: %m", path, line); + continue; + } + if (r == 0) { + log_warning("%s:%u: Bad syntax", path, line); + continue; + } + + if (streq(field, "default")) + r = free_and_strdup(&config->default_pattern, p); + else if (streq(field, "timeout")) + r = free_and_strdup(&config->timeout, p); + else if (streq(field, "editor")) + r = free_and_strdup(&config->editor, p); + else if (streq(field, "auto-entries")) + r = free_and_strdup(&config->auto_entries, p); + else if (streq(field, "auto-firmware")) + r = free_and_strdup(&config->auto_firmware, p); + else if (streq(field, "console-mode")) + r = free_and_strdup(&config->console_mode, p); + else { + log_notice("%s:%u: Unknown line \"%s\"", path, line, field); + continue; + } + if (r < 0) + return log_error_errno(r, "%s:%u: Error while reading: %m", path, line); + } + + return 1; +} + +static int boot_entry_compare(const BootEntry *a, const BootEntry *b) { + return str_verscmp(a->id, b->id); +} + +static int boot_entries_find(const char *dir, BootEntry **ret_entries, size_t *ret_n_entries) { + _cleanup_strv_free_ char **files = NULL; + char **f; + int r; + BootEntry *array = NULL; + size_t n_allocated = 0, n = 0; + + assert(dir); + assert(ret_entries); + assert(ret_n_entries); + + r = conf_files_list(&files, ".conf", NULL, 0, dir, NULL); + if (r < 0) + return log_error_errno(r, "Failed to list files in \"%s\": %m", dir); + + STRV_FOREACH(f, files) { + if (!GREEDY_REALLOC0(array, n_allocated, n + 1)) + return log_oom(); + + r = boot_entry_load(*f, array + n); + if (r < 0) + continue; + + n++; + } + + typesafe_qsort(array, n, boot_entry_compare); + + *ret_entries = array; + *ret_n_entries = n; + + return 0; +} + +static bool find_nonunique(BootEntry *entries, size_t n_entries, bool *arr) { + size_t i, j; + bool non_unique = false; + + assert(entries || n_entries == 0); + assert(arr || n_entries == 0); + + for (i = 0; i < n_entries; i++) + arr[i] = false; + + for (i = 0; i < n_entries; i++) + for (j = 0; j < n_entries; j++) + if (i != j && streq(boot_entry_title(entries + i), + boot_entry_title(entries + j))) + non_unique = arr[i] = arr[j] = true; + + return non_unique; +} + +static int boot_entries_uniquify(BootEntry *entries, size_t n_entries) { + char *s; + size_t i; + int r; + bool arr[n_entries]; + + assert(entries || n_entries == 0); + + /* Find _all_ non-unique titles */ + if (!find_nonunique(entries, n_entries, arr)) + return 0; + + /* Add version to non-unique titles */ + for (i = 0; i < n_entries; i++) + if (arr[i] && entries[i].version) { + r = asprintf(&s, "%s (%s)", boot_entry_title(entries + i), entries[i].version); + if (r < 0) + return -ENOMEM; + + free_and_replace(entries[i].show_title, s); + } + + if (!find_nonunique(entries, n_entries, arr)) + return 0; + + /* Add machine-id to non-unique titles */ + for (i = 0; i < n_entries; i++) + if (arr[i] && entries[i].machine_id) { + r = asprintf(&s, "%s (%s)", boot_entry_title(entries + i), entries[i].machine_id); + if (r < 0) + return -ENOMEM; + + free_and_replace(entries[i].show_title, s); + } + + if (!find_nonunique(entries, n_entries, arr)) + return 0; + + /* Add file name to non-unique titles */ + for (i = 0; i < n_entries; i++) + if (arr[i]) { + r = asprintf(&s, "%s (%s)", boot_entry_title(entries + i), entries[i].id); + if (r < 0) + return -ENOMEM; + + free_and_replace(entries[i].show_title, s); + } + + return 0; +} + +static int boot_entries_select_default(const BootConfig *config) { + int i; + + assert(config); + + if (config->entry_oneshot) + for (i = config->n_entries - 1; i >= 0; i--) + if (streq(config->entry_oneshot, config->entries[i].id)) { + log_debug("Found default: id \"%s\" is matched by LoaderEntryOneShot", + config->entries[i].id); + return i; + } + + if (config->entry_default) + for (i = config->n_entries - 1; i >= 0; i--) + if (streq(config->entry_default, config->entries[i].id)) { + log_debug("Found default: id \"%s\" is matched by LoaderEntryDefault", + config->entries[i].id); + return i; + } + + if (config->default_pattern) + for (i = config->n_entries - 1; i >= 0; i--) + if (fnmatch(config->default_pattern, config->entries[i].id, FNM_CASEFOLD) == 0) { + log_debug("Found default: id \"%s\" is matched by pattern \"%s\"", + config->entries[i].id, config->default_pattern); + return i; + } + + if (config->n_entries > 0) + log_debug("Found default: last entry \"%s\"", config->entries[config->n_entries - 1].id); + else + log_debug("Found no default boot entry :("); + + return config->n_entries - 1; /* -1 means "no default" */ +} + +int boot_entries_load_config(const char *esp_path, BootConfig *config) { + const char *p; + int r; + + assert(esp_path); + assert(config); + + p = strjoina(esp_path, "/loader/loader.conf"); + r = boot_loader_read_conf(p, config); + if (r < 0) + return r; + + p = strjoina(esp_path, "/loader/entries"); + r = boot_entries_find(p, &config->entries, &config->n_entries); + if (r < 0) + return r; + + r = boot_entries_uniquify(config->entries, config->n_entries); + if (r < 0) + return log_error_errno(r, "Failed to uniquify boot entries: %m"); + + if (is_efi_boot()) { + r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderEntryOneShot", &config->entry_oneshot); + if (r < 0 && r != -ENOENT) + return log_error_errno(r, "Failed to read EFI var \"LoaderEntryOneShot\": %m"); + + r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderEntryDefault", &config->entry_default); + if (r < 0 && r != -ENOENT) + return log_error_errno(r, "Failed to read EFI var \"LoaderEntryDefault\": %m"); + } + + config->default_entry = boot_entries_select_default(config); + return 0; +} + +/********************************************************************************/ + +static int verify_esp( + const char *p, + bool searching, + bool unprivileged_mode, + uint32_t *ret_part, + uint64_t *ret_pstart, + uint64_t *ret_psize, + sd_id128_t *ret_uuid) { +#if HAVE_BLKID + _cleanup_(blkid_free_probep) blkid_probe b = NULL; + _cleanup_free_ char *node = NULL; + const char *v; +#endif + uint64_t pstart = 0, psize = 0; + struct stat st, st2; + const char *t2; + struct statfs sfs; + sd_id128_t uuid = SD_ID128_NULL; + uint32_t part = 0; + bool relax_checks; + int r; + + assert(p); + + relax_checks = getenv_bool("SYSTEMD_RELAX_ESP_CHECKS") > 0; + + /* Non-root user can only check the status, so if an error occured in the following, it does not cause any + * issues. Let's also, silence the error messages. */ + + if (!relax_checks) { + if (statfs(p, &sfs) < 0) { + /* If we are searching for the mount point, don't generate a log message if we can't find the path */ + if (errno == ENOENT && searching) + return -ENOENT; + + return log_full_errno(unprivileged_mode && errno == EACCES ? LOG_DEBUG : LOG_ERR, errno, + "Failed to check file system type of \"%s\": %m", p); + } + + if (!F_TYPE_EQUAL(sfs.f_type, MSDOS_SUPER_MAGIC)) { + if (searching) + return -EADDRNOTAVAIL; + + log_error("File system \"%s\" is not a FAT EFI System Partition (ESP) file system.", p); + return -ENODEV; + } + } + + if (stat(p, &st) < 0) + return log_full_errno(unprivileged_mode && errno == EACCES ? LOG_DEBUG : LOG_ERR, errno, + "Failed to determine block device node of \"%s\": %m", p); + + if (major(st.st_dev) == 0) { + log_error("Block device node of %p is invalid.", p); + return -ENODEV; + } + + t2 = strjoina(p, "/.."); + r = stat(t2, &st2); + if (r < 0) + return log_full_errno(unprivileged_mode && errno == EACCES ? LOG_DEBUG : LOG_ERR, errno, + "Failed to determine block device node of parent of \"%s\": %m", p); + + if (st.st_dev == st2.st_dev) { + log_error("Directory \"%s\" is not the root of the EFI System Partition (ESP) file system.", p); + return -ENODEV; + } + + /* In a container we don't have access to block devices, skip this part of the verification, we trust the + * container manager set everything up correctly on its own. Also skip the following verification for non-root user. */ + if (detect_container() > 0 || unprivileged_mode || relax_checks) + goto finish; + +#if HAVE_BLKID + r = device_path_make_major_minor(S_IFBLK, st.st_dev, &node); + if (r < 0) + return log_error_errno(r, "Failed to format major/minor device path: %m"); + errno = 0; + b = blkid_new_probe_from_filename(node); + if (!b) + return log_error_errno(errno ?: ENOMEM, "Failed to open file system \"%s\": %m", p); + + blkid_probe_enable_superblocks(b, 1); + blkid_probe_set_superblocks_flags(b, BLKID_SUBLKS_TYPE); + blkid_probe_enable_partitions(b, 1); + blkid_probe_set_partitions_flags(b, BLKID_PARTS_ENTRY_DETAILS); + + errno = 0; + r = blkid_do_safeprobe(b); + if (r == -2) { + log_error("File system \"%s\" is ambiguous.", p); + return -ENODEV; + } else if (r == 1) { + log_error("File system \"%s\" does not contain a label.", p); + return -ENODEV; + } else if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe file system \"%s\": %m", p); + + errno = 0; + r = blkid_probe_lookup_value(b, "TYPE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe file system type \"%s\": %m", p); + if (!streq(v, "vfat")) { + log_error("File system \"%s\" is not FAT.", p); + return -ENODEV; + } + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_SCHEME", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition scheme \"%s\": %m", p); + if (!streq(v, "gpt")) { + log_error("File system \"%s\" is not on a GPT partition table.", p); + return -ENODEV; + } + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_TYPE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition type UUID \"%s\": %m", p); + if (!streq(v, "c12a7328-f81f-11d2-ba4b-00a0c93ec93b")) { + log_error("File system \"%s\" has wrong type for an EFI System Partition (ESP).", p); + return -ENODEV; + } + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_UUID", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition entry UUID \"%s\": %m", p); + r = sd_id128_from_string(v, &uuid); + if (r < 0) { + log_error("Partition \"%s\" has invalid UUID \"%s\".", p, v); + return -EIO; + } + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_NUMBER", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition number \"%s\": m", p); + r = safe_atou32(v, &part); + if (r < 0) + return log_error_errno(r, "Failed to parse PART_ENTRY_NUMBER field."); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_OFFSET", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition offset \"%s\": %m", p); + r = safe_atou64(v, &pstart); + if (r < 0) + return log_error_errno(r, "Failed to parse PART_ENTRY_OFFSET field."); + + errno = 0; + r = blkid_probe_lookup_value(b, "PART_ENTRY_SIZE", &v, NULL); + if (r != 0) + return log_error_errno(errno ?: EIO, "Failed to probe partition size \"%s\": %m", p); + r = safe_atou64(v, &psize); + if (r < 0) + return log_error_errno(r, "Failed to parse PART_ENTRY_SIZE field."); +#endif + +finish: + if (ret_part) + *ret_part = part; + if (ret_pstart) + *ret_pstart = pstart; + if (ret_psize) + *ret_psize = psize; + if (ret_uuid) + *ret_uuid = uuid; + + return 0; +} + +int find_esp_and_warn( + const char *path, + bool unprivileged_mode, + char **ret_path, + uint32_t *ret_part, + uint64_t *ret_pstart, + uint64_t *ret_psize, + sd_id128_t *ret_uuid) { + + int r; + + /* This logs about all errors except: + * + * -ENOKEY → when we can't find the partition + * -EACCESS → when unprivileged_mode is true, and we can't access something + */ + + if (path) { + r = verify_esp(path, false, unprivileged_mode, ret_part, ret_pstart, ret_psize, ret_uuid); + if (r < 0) + return r; + + goto found; + } + + path = getenv("SYSTEMD_ESP_PATH"); + if (path) { + if (!path_is_valid(path) || !path_is_absolute(path)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "$SYSTEMD_ESP_PATH does not refer to absolute path, refusing to use it: %s", + path); + + /* Note: when the user explicitly configured things with an env var we won't validate the mount + * point. After all we want this to be useful for testing. */ + goto found; + } + + FOREACH_STRING(path, "/efi", "/boot", "/boot/efi") { + + r = verify_esp(path, true, unprivileged_mode, ret_part, ret_pstart, ret_psize, ret_uuid); + if (r >= 0) + goto found; + if (!IN_SET(r, -ENOENT, -EADDRNOTAVAIL)) /* This one is not it */ + return r; + } + + /* No logging here */ + return -ENOKEY; + +found: + if (ret_path) { + char *c; + + c = strdup(path); + if (!c) + return log_oom(); + + *ret_path = c; + } + + return 0; +} + +int find_default_boot_entry( + const char *esp_path, + char **esp_where, + BootConfig *config, + const BootEntry **e) { + + _cleanup_free_ char *where = NULL; + int r; + + assert(config); + assert(e); + + r = find_esp_and_warn(esp_path, false, &where, NULL, NULL, NULL, NULL); + if (r < 0) + return r; + + r = boot_entries_load_config(where, config); + if (r < 0) + return log_error_errno(r, "Failed to load bootspec config from \"%s/loader\": %m", where); + + if (config->default_entry < 0) + return log_error_errno(SYNTHETIC_ERRNO(ENOENT), + "No entry suitable as default, refusing to guess."); + + *e = &config->entries[config->default_entry]; + log_debug("Found default boot entry in file \"%s\"", (*e)->path); + + if (esp_where) + *esp_where = TAKE_PTR(where); + + return 0; +} |