diff options
Diffstat (limited to 'src/sysupdate/sysupdate-resource.c')
-rw-r--r-- | src/sysupdate/sysupdate-resource.c | 639 |
1 files changed, 639 insertions, 0 deletions
diff --git a/src/sysupdate/sysupdate-resource.c b/src/sysupdate/sysupdate-resource.c new file mode 100644 index 0000000..035bea9 --- /dev/null +++ b/src/sysupdate/sysupdate-resource.c @@ -0,0 +1,639 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <fcntl.h> +#include <sys/stat.h> +#include <unistd.h> + +#include "alloc-util.h" +#include "blockdev-util.h" +#include "chase-symlinks.h" +#include "device-util.h" +#include "dirent-util.h" +#include "env-util.h" +#include "fd-util.h" +#include "fileio.h" +#include "glyph-util.h" +#include "gpt.h" +#include "hexdecoct.h" +#include "import-util.h" +#include "macro.h" +#include "process-util.h" +#include "sort-util.h" +#include "string-table.h" +#include "sysupdate-cache.h" +#include "sysupdate-instance.h" +#include "sysupdate-pattern.h" +#include "sysupdate-resource.h" +#include "sysupdate.h" +#include "utf8.h" + +void resource_destroy(Resource *rr) { + assert(rr); + + free(rr->path); + strv_free(rr->patterns); + + for (size_t i = 0; i < rr->n_instances; i++) + instance_free(rr->instances[i]); + free(rr->instances); +} + +static int resource_add_instance( + Resource *rr, + const char *path, + const InstanceMetadata *f, + Instance **ret) { + + Instance *i; + int r; + + assert(rr); + assert(path); + assert(f); + assert(f->version); + + if (!GREEDY_REALLOC(rr->instances, rr->n_instances + 1)) + return log_oom(); + + r = instance_new(rr, path, f, &i); + if (r < 0) + return r; + + rr->instances[rr->n_instances++] = i; + + if (ret) + *ret = i; + + return 0; +} + +static int resource_load_from_directory( + Resource *rr, + mode_t m) { + + _cleanup_(closedirp) DIR *d = NULL; + int r; + + assert(rr); + assert(IN_SET(rr->type, RESOURCE_TAR, RESOURCE_REGULAR_FILE, RESOURCE_DIRECTORY, RESOURCE_SUBVOLUME)); + assert(IN_SET(m, S_IFREG, S_IFDIR)); + + d = opendir(rr->path); + if (!d) { + if (errno == ENOENT) { + log_debug("Directory %s does not exist, not loading any resources.", rr->path); + return 0; + } + + return log_error_errno(errno, "Failed to open directory '%s': %m", rr->path); + } + + for (;;) { + _cleanup_(instance_metadata_destroy) InstanceMetadata extracted_fields = INSTANCE_METADATA_NULL; + _cleanup_free_ char *joined = NULL; + Instance *instance; + struct dirent *de; + struct stat st; + + errno = 0; + de = readdir_no_dot(d); + if (!de) { + if (errno != 0) + return log_error_errno(errno, "Failed to read directory '%s': %m", rr->path); + break; + } + + switch (de->d_type) { + + case DT_UNKNOWN: + break; + + case DT_DIR: + if (m != S_IFDIR) + continue; + + break; + + case DT_REG: + if (m != S_IFREG) + continue; + break; + + default: + continue; + } + + if (fstatat(dirfd(d), de->d_name, &st, AT_NO_AUTOMOUNT) < 0) { + if (errno == ENOENT) /* Gone by now? */ + continue; + + return log_error_errno(errno, "Failed to stat %s/%s: %m", rr->path, de->d_name); + } + + if ((st.st_mode & S_IFMT) != m) + continue; + + r = pattern_match_many(rr->patterns, de->d_name, &extracted_fields); + if (r < 0) + return log_error_errno(r, "Failed to match pattern: %m"); + if (r == 0) + continue; + + joined = path_join(rr->path, de->d_name); + if (!joined) + return log_oom(); + + r = resource_add_instance(rr, joined, &extracted_fields, &instance); + if (r < 0) + return r; + + /* Inherit these from the source, if not explicitly overwritten */ + if (instance->metadata.mtime == USEC_INFINITY) + instance->metadata.mtime = timespec_load(&st.st_mtim) ?: USEC_INFINITY; + + if (instance->metadata.mode == MODE_INVALID) + instance->metadata.mode = st.st_mode & 0775; /* mask out world-writability and suid and stuff, for safety */ + } + + return 0; +} + +static int resource_load_from_blockdev(Resource *rr) { + _cleanup_(fdisk_unref_contextp) struct fdisk_context *c = NULL; + _cleanup_(fdisk_unref_tablep) struct fdisk_table *t = NULL; + size_t n_partitions; + int r; + + assert(rr); + + c = fdisk_new_context(); + if (!c) + return log_oom(); + + r = fdisk_assign_device(c, rr->path, /* readonly= */ true); + if (r < 0) + return log_error_errno(r, "Failed to open device '%s': %m", rr->path); + + if (!fdisk_is_labeltype(c, FDISK_DISKLABEL_GPT)) + return log_error_errno(SYNTHETIC_ERRNO(EHWPOISON), "Disk %s has no GPT disk label, not suitable.", rr->path); + + r = fdisk_get_partitions(c, &t); + if (r < 0) + return log_error_errno(r, "Failed to acquire partition table: %m"); + + n_partitions = fdisk_table_get_nents(t); + for (size_t i = 0; i < n_partitions; i++) { + _cleanup_(instance_metadata_destroy) InstanceMetadata extracted_fields = INSTANCE_METADATA_NULL; + _cleanup_(partition_info_destroy) PartitionInfo pinfo = PARTITION_INFO_NULL; + Instance *instance; + + r = read_partition_info(c, t, i, &pinfo); + if (r < 0) + return r; + if (r == 0) /* not assigned */ + continue; + + /* Check if partition type matches */ + if (rr->partition_type_set && !sd_id128_equal(pinfo.type, rr->partition_type)) + continue; + + /* A label of "_empty" means "not used so far" for us */ + if (streq_ptr(pinfo.label, "_empty")) { + rr->n_empty++; + continue; + } + + r = pattern_match_many(rr->patterns, pinfo.label, &extracted_fields); + if (r < 0) + return log_error_errno(r, "Failed to match pattern: %m"); + if (r == 0) + continue; + + r = resource_add_instance(rr, pinfo.device, &extracted_fields, &instance); + if (r < 0) + return r; + + instance->partition_info = pinfo; + pinfo = (PartitionInfo) PARTITION_INFO_NULL; + + /* Inherit data from source if not configured explicitly */ + if (!instance->metadata.partition_uuid_set) { + instance->metadata.partition_uuid = instance->partition_info.uuid; + instance->metadata.partition_uuid_set = true; + } + + if (!instance->metadata.partition_flags_set) { + instance->metadata.partition_flags = instance->partition_info.flags; + instance->metadata.partition_flags_set = true; + } + + if (instance->metadata.read_only < 0) + instance->metadata.read_only = instance->partition_info.read_only; + } + + return 0; +} + +static int download_manifest( + const char *url, + bool verify_signature, + char **ret_buffer, + size_t *ret_size) { + + _cleanup_free_ char *buffer = NULL, *suffixed_url = NULL; + _cleanup_(close_pairp) int pfd[2] = { -1, -1 }; + _cleanup_fclose_ FILE *manifest = NULL; + size_t size = 0; + pid_t pid; + int r; + + assert(url); + assert(ret_buffer); + assert(ret_size); + + /* Download a SHA256SUMS file as manifest */ + + r = import_url_append_component(url, "SHA256SUMS", &suffixed_url); + if (r < 0) + return log_error_errno(r, "Failed to append SHA256SUMS to URL: %m"); + + if (pipe2(pfd, O_CLOEXEC) < 0) + return log_error_errno(errno, "Failed to allocate pipe: %m"); + + log_info("%s Acquiring manifest file %s%s", special_glyph(SPECIAL_GLYPH_DOWNLOAD), + suffixed_url, special_glyph(SPECIAL_GLYPH_ELLIPSIS)); + + r = safe_fork("(sd-pull)", FORK_RESET_SIGNALS|FORK_DEATHSIG|FORK_LOG, &pid); + if (r < 0) + return r; + if (r == 0) { + /* Child */ + + const char *cmdline[] = { + "systemd-pull", + "raw", + "--direct", /* just download the specified URL, don't download anything else */ + "--verify", verify_signature ? "signature" : "no", /* verify the manifest file */ + suffixed_url, + "-", /* write to stdout */ + NULL + }; + + pfd[0] = safe_close(pfd[0]); + + r = rearrange_stdio(-1, pfd[1], STDERR_FILENO); + if (r < 0) { + log_error_errno(r, "Failed to rearrange stdin/stdout: %m"); + _exit(EXIT_FAILURE); + } + + (void) unsetenv("NOTIFY_SOCKET"); + execv(pull_binary_path(), (char *const*) cmdline); + log_error_errno(errno, "Failed to execute %s tool: %m", pull_binary_path()); + _exit(EXIT_FAILURE); + }; + + pfd[1] = safe_close(pfd[1]); + + /* We'll first load the entire manifest into memory before parsing it. That's because the + * systemd-pull tool can validate the download only after its completion, but still pass the data to + * us as it runs. We thus need to check the return value of the process *before* parsing, to be + * reasonably safe. */ + + manifest = fdopen(pfd[0], "r"); + if (!manifest) + return log_error_errno(errno, "Failed allocate FILE object for manifest file: %m"); + + TAKE_FD(pfd[0]); + + r = read_full_stream(manifest, &buffer, &size); + if (r < 0) + return log_error_errno(r, "Failed to read manifest file from child: %m"); + + manifest = safe_fclose(manifest); + + r = wait_for_terminate_and_check("(sd-pull)", pid, WAIT_LOG); + if (r < 0) + return r; + if (r != 0) + return -EPROTO; + + *ret_buffer = TAKE_PTR(buffer); + *ret_size = size; + + return 0; +} + +static int resource_load_from_web( + Resource *rr, + bool verify, + Hashmap **web_cache) { + + size_t manifest_size = 0, left = 0; + _cleanup_free_ char *buf = NULL; + const char *manifest, *p; + size_t line_nr = 1; + WebCacheItem *ci; + int r; + + assert(rr); + + ci = web_cache ? web_cache_get_item(*web_cache, rr->path, verify) : NULL; + if (ci) { + log_debug("Manifest web cache hit for %s.", rr->path); + + manifest = (char*) ci->data; + manifest_size = ci->size; + } else { + log_debug("Manifest web cache miss for %s.", rr->path); + + r = download_manifest(rr->path, verify, &buf, &manifest_size); + if (r < 0) + return r; + + manifest = buf; + } + + if (memchr(manifest, 0, manifest_size)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Manifest file has embedded NUL byte, refusing."); + if (!utf8_is_valid_n(manifest, manifest_size)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Manifest file is not valid UTF-8, refusing."); + + p = manifest; + left = manifest_size; + + while (left > 0) { + _cleanup_(instance_metadata_destroy) InstanceMetadata extracted_fields = INSTANCE_METADATA_NULL; + _cleanup_free_ char *fn = NULL; + _cleanup_free_ void *h = NULL; + Instance *instance; + const char *e; + size_t hlen; + + /* 64 character hash + separator + filename + newline */ + if (left < 67) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Corrupt manifest at line %zu, refusing.", line_nr); + + if (p[0] == '\\') + return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), "File names with escapes not supported in manifest at line %zu, refusing.", line_nr); + + r = unhexmem(p, 64, &h, &hlen); + if (r < 0) + return log_error_errno(r, "Failed to parse digest at manifest line %zu, refusing.", line_nr); + + p += 64, left -= 64; + + if (*p != ' ') + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Missing space separator at manifest line %zu, refusing.", line_nr); + p++, left--; + + if (!IN_SET(*p, '*', ' ')) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Missing binary/text input marker at manifest line %zu, refusing.", line_nr); + p++, left--; + + e = memchr(p, '\n', left); + if (!e) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Truncated manifest file at line %zu, refusing.", line_nr); + if (e == p) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Empty filename specified at manifest line %zu, refusing.", line_nr); + + fn = strndup(p, e - p); + if (!fn) + return log_oom(); + + if (!filename_is_valid(fn)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Invalid filename specified at manifest line %zu, refusing.", line_nr); + if (string_has_cc(fn, NULL)) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "Filename contains control characters at manifest line %zu, refusing.", line_nr); + + r = pattern_match_many(rr->patterns, fn, &extracted_fields); + if (r < 0) + return log_error_errno(r, "Failed to match pattern: %m"); + if (r > 0) { + _cleanup_free_ char *path = NULL; + + r = import_url_append_component(rr->path, fn, &path); + if (r < 0) + return log_error_errno(r, "Failed to build instance URL: %m"); + + r = resource_add_instance(rr, path, &extracted_fields, &instance); + if (r < 0) + return r; + + assert(hlen == sizeof(instance->metadata.sha256sum)); + + if (instance->metadata.sha256sum_set) { + if (memcmp(instance->metadata.sha256sum, h, hlen) != 0) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), "SHA256 sum parsed from filename and manifest don't match at line %zu, refusing.", line_nr); + } else { + memcpy(instance->metadata.sha256sum, h, hlen); + instance->metadata.sha256sum_set = true; + } + } + + left -= (e - p) + 1; + p = e + 1; + + line_nr++; + } + + if (!ci && web_cache) { + r = web_cache_add_item(web_cache, rr->path, verify, manifest, manifest_size); + if (r < 0) + log_debug_errno(r, "Failed to add manifest '%s' to cache, ignoring: %m", rr->path); + else + log_debug("Added manifest '%s' to cache.", rr->path); + } + + return 0; +} + +static int instance_cmp(Instance *const*a, Instance *const*b) { + int r; + + assert(a); + assert(b); + assert(*a); + assert(*b); + assert((*a)->metadata.version); + assert((*b)->metadata.version); + + /* Newest version at the beginning */ + r = strverscmp_improved((*a)->metadata.version, (*b)->metadata.version); + if (r != 0) + return -r; + + /* Instances don't have to be uniquely named (uniqueness on partition tables is not enforced at all, + * and since we allow multiple matching patterns not even in directories they are unique). Hence + * let's order by path as secondary ordering key. */ + return path_compare((*a)->path, (*b)->path); +} + +int resource_load_instances(Resource *rr, bool verify, Hashmap **web_cache) { + int r; + + assert(rr); + + switch (rr->type) { + + case RESOURCE_TAR: + case RESOURCE_REGULAR_FILE: + r = resource_load_from_directory(rr, S_IFREG); + break; + + case RESOURCE_DIRECTORY: + case RESOURCE_SUBVOLUME: + r = resource_load_from_directory(rr, S_IFDIR); + break; + + case RESOURCE_PARTITION: + r = resource_load_from_blockdev(rr); + break; + + case RESOURCE_URL_FILE: + case RESOURCE_URL_TAR: + r = resource_load_from_web(rr, verify, web_cache); + break; + + default: + assert_not_reached(); + } + if (r < 0) + return r; + + typesafe_qsort(rr->instances, rr->n_instances, instance_cmp); + return 0; +} + +Instance* resource_find_instance(Resource *rr, const char *version) { + Instance key = { + .metadata.version = (char*) version, + }, *k = &key; + + Instance **found; + found = typesafe_bsearch(&k, rr->instances, rr->n_instances, instance_cmp); + if (!found) + return NULL; + + return *found; +} + +int resource_resolve_path( + Resource *rr, + const char *root, + const char *node) { + + _cleanup_free_ char *p = NULL; + dev_t d; + int r; + + assert(rr); + + if (rr->path_auto) { + + /* NB: we don't actually check the backing device of the root fs "/", but of "/usr", in order + * to support environments where the root fs is a tmpfs, and the OS itself placed exclusively + * in /usr/. */ + + if (rr->type != RESOURCE_PARTITION) + return log_error_errno(SYNTHETIC_ERRNO(EOPNOTSUPP), + "Automatic root path discovery only supported for partition resources."); + + if (node) { /* If --image= is specified, directly use the loopback device */ + r = free_and_strdup_warn(&rr->path, node); + if (r < 0) + return r; + + return 0; + } + + if (root) + return log_error_errno(SYNTHETIC_ERRNO(EPERM), + "Block device is not allowed when using --root= mode."); + + r = get_block_device_harder("/usr/", &d); + + } else if (rr->type == RESOURCE_PARTITION) { + _cleanup_close_ int fd = -1, real_fd = -1; + _cleanup_free_ char *resolved = NULL; + struct stat st; + + r = chase_symlinks(rr->path, root, CHASE_PREFIX_ROOT, &resolved, &fd); + if (r < 0) + return log_error_errno(r, "Failed to resolve '%s': %m", rr->path); + + if (fstat(fd, &st) < 0) + return log_error_errno(errno, "Failed to stat '%s': %m", resolved); + + if (S_ISBLK(st.st_mode) && root) + return log_error_errno(SYNTHETIC_ERRNO(EPERM), "When using --root= or --image= access to device nodes is prohibited."); + + if (S_ISREG(st.st_mode) || S_ISBLK(st.st_mode)) { + /* Not a directory, hence no need to find backing block device for the path */ + free_and_replace(rr->path, resolved); + return 0; + } + + if (!S_ISDIR(st.st_mode)) + return log_error_errno(SYNTHETIC_ERRNO(ENOTDIR), "Target path '%s' does not refer to regular file, directory or block device, refusing.", rr->path); + + if (node) { /* If --image= is specified all file systems are backed by the same loopback device, hence shortcut things. */ + r = free_and_strdup_warn(&rr->path, node); + if (r < 0) + return r; + + return 0; + } + + real_fd = fd_reopen(fd, O_RDONLY|O_CLOEXEC|O_DIRECTORY); + if (real_fd < 0) + return log_error_errno(real_fd, "Failed to convert O_PATH file descriptor for %s to regular file descriptor: %m", rr->path); + + r = get_block_device_harder_fd(fd, &d); + + } else if (RESOURCE_IS_FILESYSTEM(rr->type) && root) { + _cleanup_free_ char *resolved = NULL; + + r = chase_symlinks(rr->path, root, CHASE_PREFIX_ROOT, &resolved, NULL); + if (r < 0) + return log_error_errno(r, "Failed to resolve '%s': %m", rr->path); + + free_and_replace(rr->path, resolved); + return 0; + } else + return 0; /* Otherwise assume there's nothing to resolve */ + + if (r < 0) + return log_error_errno(r, "Failed to determine block device of file system: %m"); + + r = block_get_whole_disk(d, &d); + if (r < 0) + return log_error_errno(r, "Failed to find whole disk device for partition backing file system: %m"); + if (r == 0) + return log_error_errno(SYNTHETIC_ERRNO(EINVAL), + "File system is not placed on a partition block device, cannot determine whole block device backing root file system."); + + r = devname_from_devnum(S_IFBLK, d, &p); + if (r < 0) + return r; + + if (rr->path) + log_info("Automatically discovered block device '%s' from '%s'.", p, rr->path); + else + log_info("Automatically discovered root block device '%s'.", p); + + free_and_replace(rr->path, p); + return 1; +} + +static const char *resource_type_table[_RESOURCE_TYPE_MAX] = { + [RESOURCE_URL_FILE] = "url-file", + [RESOURCE_URL_TAR] = "url-tar", + [RESOURCE_TAR] = "tar", + [RESOURCE_PARTITION] = "partition", + [RESOURCE_REGULAR_FILE] = "regular-file", + [RESOURCE_DIRECTORY] = "directory", + [RESOURCE_SUBVOLUME] = "subvolume", +}; + +DEFINE_STRING_TABLE_LOOKUP(resource_type, ResourceType); |