From: Yu Watanabe Date: Thu, 31 Dec 2020 23:48:52 +0000 (+0900) Subject: util: move unit-file.[ch] to src/basic X-Git-Tag: v248-rc1~304^2~29 X-Git-Url: http://git-history.diyao.me/?a=commitdiff_plain;h=af182ae1dc35a48276e9fe0aaa9454377b4a667b;p=systemd%2F.git util: move unit-file.[ch] to src/basic As basic/path-lookup.[ch] depend on them. --- diff --git a/src/basic/meson.build b/src/basic/meson.build index d791f77c65..c7d6872fbf 100644 --- a/src/basic/meson.build +++ b/src/basic/meson.build @@ -244,6 +244,8 @@ basic_sources = files(''' unaligned.h unit-def.c unit-def.h + unit-file.c + unit-file.h unit-name.c unit-name.h user-util.c diff --git a/src/basic/unit-file.c b/src/basic/unit-file.c new file mode 100644 index 0000000000..f27352905d --- /dev/null +++ b/src/basic/unit-file.c @@ -0,0 +1,601 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include "sd-id128.h" + +#include "dirent-util.h" +#include "fd-util.h" +#include "fs-util.h" +#include "macro.h" +#include "path-lookup.h" +#include "set.h" +#include "special.h" +#include "stat-util.h" +#include "string-util.h" +#include "strv.h" +#include "unit-file.h" + +bool unit_type_may_alias(UnitType type) { + return IN_SET(type, + UNIT_SERVICE, + UNIT_SOCKET, + UNIT_TARGET, + UNIT_DEVICE, + UNIT_TIMER, + UNIT_PATH); +} + +bool unit_type_may_template(UnitType type) { + return IN_SET(type, + UNIT_SERVICE, + UNIT_SOCKET, + UNIT_TARGET, + UNIT_TIMER, + UNIT_PATH); +} + +int unit_symlink_name_compatible(const char *symlink, const char *target, bool instance_propagation) { + _cleanup_free_ char *template = NULL; + int r, un_type1, un_type2; + + un_type1 = unit_name_classify(symlink); + + /* The straightforward case: the symlink name matches the target and we have a valid unit */ + if (streq(symlink, target) && + (un_type1 & (UNIT_NAME_PLAIN | UNIT_NAME_INSTANCE))) + return 1; + + r = unit_name_template(symlink, &template); + if (r == -EINVAL) + return 0; /* Not a template */ + if (r < 0) + return r; + + un_type2 = unit_name_classify(target); + + /* An instance name points to a target that is just the template name */ + if (un_type1 == UNIT_NAME_INSTANCE && + un_type2 == UNIT_NAME_TEMPLATE && + streq(template, target)) + return 1; + + /* foo@.target.requires/bar@.service: instance will be propagated */ + if (instance_propagation && + un_type1 == UNIT_NAME_TEMPLATE && + un_type2 == UNIT_NAME_TEMPLATE && + streq(template, target)) + return 1; + + return 0; +} + +int unit_validate_alias_symlink_and_warn(const char *filename, const char *target) { + const char *src, *dst; + _cleanup_free_ char *src_instance = NULL, *dst_instance = NULL; + UnitType src_unit_type, dst_unit_type; + int src_name_type, dst_name_type; + + /* Check if the *alias* symlink is valid. This applies to symlinks like + * /etc/systemd/system/dbus.service → dbus-broker.service, but not to .wants or .requires symlinks + * and such. Neither does this apply to symlinks which *link* units, i.e. symlinks to outside of the + * unit lookup path. + * + * -EINVAL is returned if the something is wrong with the source filename or the source unit type is + * not allowed to symlink, + * -EXDEV if the target filename is not a valid unit name or doesn't match the source. + */ + + src = basename(filename); + dst = basename(target); + + /* src checks */ + + src_name_type = unit_name_to_instance(src, &src_instance); + if (src_name_type < 0) + return log_notice_errno(src_name_type, + "%s: not a valid unit name \"%s\": %m", filename, src); + + src_unit_type = unit_name_to_type(src); + assert(src_unit_type >= 0); /* unit_name_to_instance() checked the suffix already */ + + if (!unit_type_may_alias(src_unit_type)) + return log_notice_errno(SYNTHETIC_ERRNO(EINVAL), + "%s: symlinks are not allowed for units of this type, rejecting.", + filename); + + if (src_name_type != UNIT_NAME_PLAIN && + !unit_type_may_template(src_unit_type)) + return log_notice_errno(SYNTHETIC_ERRNO(EINVAL), + "%s: templates not allowed for %s units, rejecting.", + filename, unit_type_to_string(src_unit_type)); + + /* dst checks */ + + dst_name_type = unit_name_to_instance(dst, &dst_instance); + if (dst_name_type < 0) + return log_notice_errno(dst_name_type == -EINVAL ? SYNTHETIC_ERRNO(EXDEV) : dst_name_type, + "%s points to \"%s\" which is not a valid unit name: %m", + filename, dst); + + if (!(dst_name_type == src_name_type || + (src_name_type == UNIT_NAME_INSTANCE && dst_name_type == UNIT_NAME_TEMPLATE))) + return log_notice_errno(SYNTHETIC_ERRNO(EXDEV), + "%s: symlink target name type \"%s\" does not match source, rejecting.", + filename, dst); + + if (dst_name_type == UNIT_NAME_INSTANCE) { + assert(src_instance); + assert(dst_instance); + if (!streq(src_instance, dst_instance)) + return log_notice_errno(SYNTHETIC_ERRNO(EXDEV), + "%s: unit symlink target \"%s\" instance name doesn't match, rejecting.", + filename, dst); + } + + dst_unit_type = unit_name_to_type(dst); + if (dst_unit_type != src_unit_type) + return log_notice_errno(SYNTHETIC_ERRNO(EXDEV), + "%s: symlink target \"%s\" has incompatible suffix, rejecting.", + filename, dst); + + return 0; +} + +#define FOLLOW_MAX 8 + +static int unit_ids_map_get( + Hashmap *unit_ids_map, + const char *unit_name, + const char **ret_fragment_path) { + + /* Resolve recursively until we hit an absolute path, i.e. a non-aliased unit. + * + * We distinguish the case where unit_name was not found in the hashmap at all, and the case where + * some symlink was broken. + * + * If a symlink target points to an instance name, then we also check for the template. */ + + const char *id = NULL; + int r; + + for (unsigned n = 0; n < FOLLOW_MAX; n++) { + const char *t = hashmap_get(unit_ids_map, id ?: unit_name); + if (!t) { + _cleanup_free_ char *template = NULL; + + if (!id) + return -ENOENT; + + r = unit_name_template(id, &template); + if (r == -EINVAL) + return -ENXIO; /* we failed to find the symlink target */ + if (r < 0) + return log_error_errno(r, "Failed to determine template name for %s: %m", id); + + t = hashmap_get(unit_ids_map, template); + if (!t) + return -ENXIO; + + /* We successfully switched from instanced name to a template, let's continue */ + } + + if (path_is_absolute(t)) { + if (ret_fragment_path) + *ret_fragment_path = t; + return 0; + } + + id = t; + } + + return -ELOOP; +} + +static bool lookup_paths_mtime_exclude(const LookupPaths *lp, const char *path) { + /* Paths that are under our exclusive control. Users shall not alter those directly. */ + + return streq_ptr(path, lp->generator) || + streq_ptr(path, lp->generator_early) || + streq_ptr(path, lp->generator_late) || + streq_ptr(path, lp->transient) || + streq_ptr(path, lp->persistent_control) || + streq_ptr(path, lp->runtime_control); +} + +#define HASH_KEY SD_ID128_MAKE(4e,86,1b,e3,39,b3,40,46,98,5d,b8,11,34,8f,c3,c1) + +bool lookup_paths_timestamp_hash_same(const LookupPaths *lp, uint64_t timestamp_hash, uint64_t *ret_new) { + struct siphash state; + + siphash24_init(&state, HASH_KEY.bytes); + + char **dir; + STRV_FOREACH(dir, (char**) lp->search_path) { + struct stat st; + + if (lookup_paths_mtime_exclude(lp, *dir)) + continue; + + /* Determine the latest lookup path modification time */ + if (stat(*dir, &st) < 0) { + if (errno == ENOENT) + continue; + + log_debug_errno(errno, "Failed to stat %s, ignoring: %m", *dir); + continue; + } + + siphash24_compress_usec_t(timespec_load(&st.st_mtim), &state); + } + + uint64_t updated = siphash24_finalize(&state); + if (ret_new) + *ret_new = updated; + if (updated != timestamp_hash) + log_debug("Modification times have changed, need to update cache."); + return updated == timestamp_hash; +} + +int unit_file_build_name_map( + const LookupPaths *lp, + uint64_t *cache_timestamp_hash, + Hashmap **unit_ids_map, + Hashmap **unit_names_map, + Set **path_cache) { + + /* Build two mappings: any name → main unit (i.e. the end result of symlink resolution), unit name → + * all aliases (i.e. the entry for a given key is a a list of all names which point to this key). The + * key is included in the value iff we saw a file or symlink with that name. In other words, if we + * have a key, but it is not present in the value for itself, there was an alias pointing to it, but + * the unit itself is not loadable. + * + * At the same, build a cache of paths where to find units. The non-const parameters are for input + * and output. Existing contents will be freed before the new contents are stored. + */ + + _cleanup_hashmap_free_ Hashmap *ids = NULL, *names = NULL; + _cleanup_set_free_free_ Set *paths = NULL; + uint64_t timestamp_hash; + char **dir; + int r; + + /* Before doing anything, check if the timestamp hash that was passed is still valid. + * If yes, do nothing. */ + if (cache_timestamp_hash && + lookup_paths_timestamp_hash_same(lp, *cache_timestamp_hash, ×tamp_hash)) + return 0; + + /* The timestamp hash is now set based on the mtimes from before when we start reading files. + * If anything is modified concurrently, we'll consider the cache outdated. */ + + if (path_cache) { + paths = set_new(&path_hash_ops_free); + if (!paths) + return log_oom(); + } + + STRV_FOREACH(dir, (char**) lp->search_path) { + struct dirent *de; + _cleanup_closedir_ DIR *d = NULL; + + d = opendir(*dir); + if (!d) { + if (errno != ENOENT) + log_warning_errno(errno, "Failed to open \"%s\", ignoring: %m", *dir); + continue; + } + + FOREACH_DIRENT_ALL(de, d, log_warning_errno(errno, "Failed to read \"%s\", ignoring: %m", *dir)) { + char *filename; + _cleanup_free_ char *_filename_free = NULL, *simplified = NULL; + const char *suffix, *dst = NULL; + bool valid_unit_name; + + valid_unit_name = unit_name_is_valid(de->d_name, UNIT_NAME_ANY); + + /* We only care about valid units and dirs with certain suffixes, let's ignore the + * rest. */ + if (!valid_unit_name && + !ENDSWITH_SET(de->d_name, ".wants", ".requires", ".d")) + continue; + + filename = path_join(*dir, de->d_name); + if (!filename) + return log_oom(); + + if (paths) { + r = set_consume(paths, filename); + if (r < 0) + return log_oom(); + /* We will still use filename below. This is safe because we know the set + * holds a reference. */ + } else + _filename_free = filename; /* Make sure we free the filename. */ + + if (!valid_unit_name) + continue; + assert_se(suffix = strrchr(de->d_name, '.')); + + /* search_path is ordered by priority (highest first). If the name is already mapped + * to something (incl. itself), it means that we have already seen it, and we should + * ignore it here. */ + if (hashmap_contains(ids, de->d_name)) + continue; + + dirent_ensure_type(d, de); + if (de->d_type == DT_LNK) { + /* We don't explicitly check for alias loops here. unit_ids_map_get() which + * limits the number of hops should be used to access the map. */ + + _cleanup_free_ char *target = NULL; + + r = readlinkat_malloc(dirfd(d), de->d_name, &target); + if (r < 0) { + log_warning_errno(r, "Failed to read symlink %s/%s, ignoring: %m", + *dir, de->d_name); + continue; + } + + const bool is_abs = path_is_absolute(target); + if (lp->root_dir || !is_abs) { + char *target_abs = path_join(is_abs ? lp->root_dir : *dir, target); + if (!target_abs) + return log_oom(); + + free_and_replace(target, target_abs); + } + + /* Get rid of "." and ".." components in target path */ + r = chase_symlinks(target, lp->root_dir, CHASE_NOFOLLOW | CHASE_NONEXISTENT, &simplified, NULL); + if (r < 0) { + log_warning_errno(r, "Failed to resolve symlink %s pointing to %s, ignoring: %m", + filename, target); + continue; + } + + /* Check if the symlink goes outside of our search path. + * If yes, it's a linked unit file or mask, and we don't care about the target name. + * Let's just store the link destination directly. + * If not, let's verify that it's a good symlink. */ + char *tail = path_startswith_strv(simplified, lp->search_path); + if (tail) { + bool self_alias; + + dst = basename(simplified); + self_alias = streq(dst, de->d_name); + + if (is_path(tail)) + log_full(self_alias ? LOG_DEBUG : LOG_WARNING, + "Suspicious symlink %s→%s, treating as alias.", + filename, simplified); + + r = unit_validate_alias_symlink_and_warn(filename, simplified); + if (r < 0) + continue; + + if (self_alias) { + /* A self-alias that has no effect */ + log_debug("%s: self-alias: %s/%s → %s, ignoring.", + __func__, *dir, de->d_name, dst); + continue; + } + + log_debug("%s: alias: %s/%s → %s", __func__, *dir, de->d_name, dst); + } else { + dst = simplified; + + log_debug("%s: linked unit file: %s/%s → %s", __func__, *dir, de->d_name, dst); + } + + } else { + dst = filename; + log_debug("%s: normal unit file: %s", __func__, dst); + } + + r = hashmap_put_strdup(&ids, de->d_name, dst); + if (r < 0) + return log_warning_errno(r, "Failed to add entry to hashmap (%s→%s): %m", + de->d_name, dst); + } + } + + /* Let's also put the names in the reverse db. */ + const char *dummy, *src; + HASHMAP_FOREACH_KEY(dummy, src, ids) { + const char *dst; + + r = unit_ids_map_get(ids, src, &dst); + if (r < 0) + continue; + + if (null_or_empty_path(dst) != 0) + continue; + + /* Do not treat instance symlinks that point to the template as aliases */ + if (unit_name_is_valid(basename(dst), UNIT_NAME_TEMPLATE) && + unit_name_is_valid(src, UNIT_NAME_INSTANCE)) + continue; + + r = string_strv_hashmap_put(&names, basename(dst), src); + if (r < 0) + return log_warning_errno(r, "Failed to add entry to hashmap (%s→%s): %m", + basename(dst), src); + } + + if (cache_timestamp_hash) + *cache_timestamp_hash = timestamp_hash; + + hashmap_free_and_replace(*unit_ids_map, ids); + hashmap_free_and_replace(*unit_names_map, names); + if (path_cache) + set_free_and_replace(*path_cache, paths); + + return 1; +} + +int unit_file_find_fragment( + Hashmap *unit_ids_map, + Hashmap *unit_name_map, + const char *unit_name, + const char **ret_fragment_path, + Set **ret_names) { + + const char *fragment = NULL; + _cleanup_free_ char *template = NULL, *instance = NULL; + _cleanup_set_free_free_ Set *names = NULL; + char **t, **nnn; + int r, name_type; + + /* Finds a fragment path, and returns the set of names: + * if we have …/foo.service and …/foo-alias.service→foo.service, + * and …/foo@.service and …/foo-alias@.service→foo@.service, + * and …/foo@inst.service, + * this should return: + * foo.service → …/foo.service, {foo.service, foo-alias.service}, + * foo-alias.service → …/foo.service, {foo.service, foo-alias.service}, + * foo@.service → …/foo@.service, {foo@.service, foo-alias@.service}, + * foo-alias@.service → …/foo@.service, {foo@.service, foo-alias@.service}, + * foo@bar.service → …/foo@.service, {foo@bar.service, foo-alias@bar.service}, + * foo-alias@bar.service → …/foo@.service, {foo@bar.service, foo-alias@bar.service}, + * foo-alias@inst.service → …/foo@inst.service, {foo@inst.service, foo-alias@inst.service}. + */ + + name_type = unit_name_to_instance(unit_name, &instance); + if (name_type < 0) + return name_type; + + names = set_new(&string_hash_ops); + if (!names) + return -ENOMEM; + + /* The unit always has its own name if it's not a template. */ + if (IN_SET(name_type, UNIT_NAME_PLAIN, UNIT_NAME_INSTANCE)) { + r = set_put_strdup(&names, unit_name); + if (r < 0) + return r; + } + + /* First try to load fragment under the original name */ + r = unit_ids_map_get(unit_ids_map, unit_name, &fragment); + if (r < 0 && !IN_SET(r, -ENOENT, -ENXIO)) + return log_debug_errno(r, "Cannot load unit %s: %m", unit_name); + + if (fragment) { + /* Add any aliases of the original name to the set of names */ + nnn = hashmap_get(unit_name_map, basename(fragment)); + STRV_FOREACH(t, nnn) { + if (name_type == UNIT_NAME_INSTANCE && unit_name_is_valid(*t, UNIT_NAME_TEMPLATE)) { + char *inst; + + r = unit_name_replace_instance(*t, instance, &inst); + if (r < 0) + return log_debug_errno(r, "Cannot build instance name %s+%s: %m", *t, instance); + + if (!streq(unit_name, inst)) + log_debug("%s: %s has alias %s", __func__, unit_name, inst); + + log_info("%s: %s+%s → %s", __func__, *t, instance, inst); + r = set_consume(names, inst); + } else { + if (!streq(unit_name, *t)) + log_debug("%s: %s has alias %s", __func__, unit_name, *t); + + r = set_put_strdup(&names, *t); + } + if (r < 0) + return r; + } + } + + if (!fragment && name_type == UNIT_NAME_INSTANCE) { + /* Look for a fragment under the template name */ + + r = unit_name_template(unit_name, &template); + if (r < 0) + return log_debug_errno(r, "Failed to determine template name: %m"); + + r = unit_ids_map_get(unit_ids_map, template, &fragment); + if (r < 0 && !IN_SET(r, -ENOENT, -ENXIO)) + return log_debug_errno(r, "Cannot load template %s: %m", template); + + if (fragment) { + /* Add any aliases of the original name to the set of names */ + nnn = hashmap_get(unit_name_map, basename(fragment)); + STRV_FOREACH(t, nnn) { + _cleanup_free_ char *inst = NULL; + const char *inst_fragment = NULL; + + r = unit_name_replace_instance(*t, instance, &inst); + if (r < 0) + return log_debug_errno(r, "Cannot build instance name %s+%s: %m", template, instance); + + /* Exclude any aliases that point in some other direction. */ + r = unit_ids_map_get(unit_ids_map, inst, &inst_fragment); + if (r < 0 && !IN_SET(r, -ENOENT, -ENXIO)) + return log_debug_errno(r, "Cannot find instance fragment %s: %m", inst); + + if (inst_fragment && + !streq(basename(inst_fragment), basename(fragment))) { + log_debug("Instance %s has fragment %s and is not an alias of %s.", + inst, inst_fragment, unit_name); + continue; + } + + if (!streq(unit_name, inst)) + log_debug("%s: %s has alias %s", __func__, unit_name, inst); + r = set_consume(names, TAKE_PTR(inst)); + if (r < 0) + return r; + } + } + } + + *ret_fragment_path = fragment; + *ret_names = TAKE_PTR(names); + + // FIXME: if instance, consider any unit names with different template name + return 0; +} + +static const char * const rlmap[] = { + "emergency", SPECIAL_EMERGENCY_TARGET, + "-b", SPECIAL_EMERGENCY_TARGET, + "rescue", SPECIAL_RESCUE_TARGET, + "single", SPECIAL_RESCUE_TARGET, + "-s", SPECIAL_RESCUE_TARGET, + "s", SPECIAL_RESCUE_TARGET, + "S", SPECIAL_RESCUE_TARGET, + "1", SPECIAL_RESCUE_TARGET, + "2", SPECIAL_MULTI_USER_TARGET, + "3", SPECIAL_MULTI_USER_TARGET, + "4", SPECIAL_MULTI_USER_TARGET, + "5", SPECIAL_GRAPHICAL_TARGET, + NULL +}; + +static const char * const rlmap_initrd[] = { + "emergency", SPECIAL_EMERGENCY_TARGET, + "rescue", SPECIAL_RESCUE_TARGET, + NULL +}; + +const char* runlevel_to_target(const char *word) { + const char * const *rlmap_ptr; + size_t i; + + if (!word) + return NULL; + + if (in_initrd()) { + word = startswith(word, "rd."); + if (!word) + return NULL; + } + + rlmap_ptr = in_initrd() ? rlmap_initrd : rlmap; + + for (i = 0; rlmap_ptr[i]; i += 2) + if (streq(word, rlmap_ptr[i])) + return rlmap_ptr[i+1]; + + return NULL; +} diff --git a/src/basic/unit-file.h b/src/basic/unit-file.h new file mode 100644 index 0000000000..5463b0ab13 --- /dev/null +++ b/src/basic/unit-file.h @@ -0,0 +1,61 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ +#pragma once + +#include + +#include "hashmap.h" +#include "time-util.h" +#include "unit-name.h" + +typedef enum UnitFileState UnitFileState; +typedef enum UnitFileScope UnitFileScope; +typedef struct LookupPaths LookupPaths; + +enum UnitFileState { + UNIT_FILE_ENABLED, + UNIT_FILE_ENABLED_RUNTIME, + UNIT_FILE_LINKED, + UNIT_FILE_LINKED_RUNTIME, + UNIT_FILE_ALIAS, + UNIT_FILE_MASKED, + UNIT_FILE_MASKED_RUNTIME, + UNIT_FILE_STATIC, + UNIT_FILE_DISABLED, + UNIT_FILE_INDIRECT, + UNIT_FILE_GENERATED, + UNIT_FILE_TRANSIENT, + UNIT_FILE_BAD, + _UNIT_FILE_STATE_MAX, + _UNIT_FILE_STATE_INVALID = -1 +}; + +enum UnitFileScope { + UNIT_FILE_SYSTEM, + UNIT_FILE_GLOBAL, + UNIT_FILE_USER, + _UNIT_FILE_SCOPE_MAX, + _UNIT_FILE_SCOPE_INVALID = -1 +}; + +bool unit_type_may_alias(UnitType type) _const_; +bool unit_type_may_template(UnitType type) _const_; + +int unit_symlink_name_compatible(const char *symlink, const char *target, bool instance_propagation); +int unit_validate_alias_symlink_and_warn(const char *filename, const char *target); + +bool lookup_paths_timestamp_hash_same(const LookupPaths *lp, uint64_t timestamp_hash, uint64_t *ret_new); +int unit_file_build_name_map( + const LookupPaths *lp, + uint64_t *cache_timestamp_hash, + Hashmap **unit_ids_map, + Hashmap **unit_names_map, + Set **path_cache); + +int unit_file_find_fragment( + Hashmap *unit_ids_map, + Hashmap *unit_name_map, + const char *unit_name, + const char **ret_fragment_path, + Set **ret_names); + +const char* runlevel_to_target(const char *rl); diff --git a/src/shared/meson.build b/src/shared/meson.build index 62270d9fd1..c56da5791d 100644 --- a/src/shared/meson.build +++ b/src/shared/meson.build @@ -252,8 +252,6 @@ shared_sources = files(''' udev-util.h uid-range.c uid-range.h - unit-file.c - unit-file.h user-record-nss.c user-record-nss.h user-record-show.c diff --git a/src/shared/unit-file.c b/src/shared/unit-file.c deleted file mode 100644 index f27352905d..0000000000 --- a/src/shared/unit-file.c +++ /dev/null @@ -1,601 +0,0 @@ -/* SPDX-License-Identifier: LGPL-2.1-or-later */ - -#include "sd-id128.h" - -#include "dirent-util.h" -#include "fd-util.h" -#include "fs-util.h" -#include "macro.h" -#include "path-lookup.h" -#include "set.h" -#include "special.h" -#include "stat-util.h" -#include "string-util.h" -#include "strv.h" -#include "unit-file.h" - -bool unit_type_may_alias(UnitType type) { - return IN_SET(type, - UNIT_SERVICE, - UNIT_SOCKET, - UNIT_TARGET, - UNIT_DEVICE, - UNIT_TIMER, - UNIT_PATH); -} - -bool unit_type_may_template(UnitType type) { - return IN_SET(type, - UNIT_SERVICE, - UNIT_SOCKET, - UNIT_TARGET, - UNIT_TIMER, - UNIT_PATH); -} - -int unit_symlink_name_compatible(const char *symlink, const char *target, bool instance_propagation) { - _cleanup_free_ char *template = NULL; - int r, un_type1, un_type2; - - un_type1 = unit_name_classify(symlink); - - /* The straightforward case: the symlink name matches the target and we have a valid unit */ - if (streq(symlink, target) && - (un_type1 & (UNIT_NAME_PLAIN | UNIT_NAME_INSTANCE))) - return 1; - - r = unit_name_template(symlink, &template); - if (r == -EINVAL) - return 0; /* Not a template */ - if (r < 0) - return r; - - un_type2 = unit_name_classify(target); - - /* An instance name points to a target that is just the template name */ - if (un_type1 == UNIT_NAME_INSTANCE && - un_type2 == UNIT_NAME_TEMPLATE && - streq(template, target)) - return 1; - - /* foo@.target.requires/bar@.service: instance will be propagated */ - if (instance_propagation && - un_type1 == UNIT_NAME_TEMPLATE && - un_type2 == UNIT_NAME_TEMPLATE && - streq(template, target)) - return 1; - - return 0; -} - -int unit_validate_alias_symlink_and_warn(const char *filename, const char *target) { - const char *src, *dst; - _cleanup_free_ char *src_instance = NULL, *dst_instance = NULL; - UnitType src_unit_type, dst_unit_type; - int src_name_type, dst_name_type; - - /* Check if the *alias* symlink is valid. This applies to symlinks like - * /etc/systemd/system/dbus.service → dbus-broker.service, but not to .wants or .requires symlinks - * and such. Neither does this apply to symlinks which *link* units, i.e. symlinks to outside of the - * unit lookup path. - * - * -EINVAL is returned if the something is wrong with the source filename or the source unit type is - * not allowed to symlink, - * -EXDEV if the target filename is not a valid unit name or doesn't match the source. - */ - - src = basename(filename); - dst = basename(target); - - /* src checks */ - - src_name_type = unit_name_to_instance(src, &src_instance); - if (src_name_type < 0) - return log_notice_errno(src_name_type, - "%s: not a valid unit name \"%s\": %m", filename, src); - - src_unit_type = unit_name_to_type(src); - assert(src_unit_type >= 0); /* unit_name_to_instance() checked the suffix already */ - - if (!unit_type_may_alias(src_unit_type)) - return log_notice_errno(SYNTHETIC_ERRNO(EINVAL), - "%s: symlinks are not allowed for units of this type, rejecting.", - filename); - - if (src_name_type != UNIT_NAME_PLAIN && - !unit_type_may_template(src_unit_type)) - return log_notice_errno(SYNTHETIC_ERRNO(EINVAL), - "%s: templates not allowed for %s units, rejecting.", - filename, unit_type_to_string(src_unit_type)); - - /* dst checks */ - - dst_name_type = unit_name_to_instance(dst, &dst_instance); - if (dst_name_type < 0) - return log_notice_errno(dst_name_type == -EINVAL ? SYNTHETIC_ERRNO(EXDEV) : dst_name_type, - "%s points to \"%s\" which is not a valid unit name: %m", - filename, dst); - - if (!(dst_name_type == src_name_type || - (src_name_type == UNIT_NAME_INSTANCE && dst_name_type == UNIT_NAME_TEMPLATE))) - return log_notice_errno(SYNTHETIC_ERRNO(EXDEV), - "%s: symlink target name type \"%s\" does not match source, rejecting.", - filename, dst); - - if (dst_name_type == UNIT_NAME_INSTANCE) { - assert(src_instance); - assert(dst_instance); - if (!streq(src_instance, dst_instance)) - return log_notice_errno(SYNTHETIC_ERRNO(EXDEV), - "%s: unit symlink target \"%s\" instance name doesn't match, rejecting.", - filename, dst); - } - - dst_unit_type = unit_name_to_type(dst); - if (dst_unit_type != src_unit_type) - return log_notice_errno(SYNTHETIC_ERRNO(EXDEV), - "%s: symlink target \"%s\" has incompatible suffix, rejecting.", - filename, dst); - - return 0; -} - -#define FOLLOW_MAX 8 - -static int unit_ids_map_get( - Hashmap *unit_ids_map, - const char *unit_name, - const char **ret_fragment_path) { - - /* Resolve recursively until we hit an absolute path, i.e. a non-aliased unit. - * - * We distinguish the case where unit_name was not found in the hashmap at all, and the case where - * some symlink was broken. - * - * If a symlink target points to an instance name, then we also check for the template. */ - - const char *id = NULL; - int r; - - for (unsigned n = 0; n < FOLLOW_MAX; n++) { - const char *t = hashmap_get(unit_ids_map, id ?: unit_name); - if (!t) { - _cleanup_free_ char *template = NULL; - - if (!id) - return -ENOENT; - - r = unit_name_template(id, &template); - if (r == -EINVAL) - return -ENXIO; /* we failed to find the symlink target */ - if (r < 0) - return log_error_errno(r, "Failed to determine template name for %s: %m", id); - - t = hashmap_get(unit_ids_map, template); - if (!t) - return -ENXIO; - - /* We successfully switched from instanced name to a template, let's continue */ - } - - if (path_is_absolute(t)) { - if (ret_fragment_path) - *ret_fragment_path = t; - return 0; - } - - id = t; - } - - return -ELOOP; -} - -static bool lookup_paths_mtime_exclude(const LookupPaths *lp, const char *path) { - /* Paths that are under our exclusive control. Users shall not alter those directly. */ - - return streq_ptr(path, lp->generator) || - streq_ptr(path, lp->generator_early) || - streq_ptr(path, lp->generator_late) || - streq_ptr(path, lp->transient) || - streq_ptr(path, lp->persistent_control) || - streq_ptr(path, lp->runtime_control); -} - -#define HASH_KEY SD_ID128_MAKE(4e,86,1b,e3,39,b3,40,46,98,5d,b8,11,34,8f,c3,c1) - -bool lookup_paths_timestamp_hash_same(const LookupPaths *lp, uint64_t timestamp_hash, uint64_t *ret_new) { - struct siphash state; - - siphash24_init(&state, HASH_KEY.bytes); - - char **dir; - STRV_FOREACH(dir, (char**) lp->search_path) { - struct stat st; - - if (lookup_paths_mtime_exclude(lp, *dir)) - continue; - - /* Determine the latest lookup path modification time */ - if (stat(*dir, &st) < 0) { - if (errno == ENOENT) - continue; - - log_debug_errno(errno, "Failed to stat %s, ignoring: %m", *dir); - continue; - } - - siphash24_compress_usec_t(timespec_load(&st.st_mtim), &state); - } - - uint64_t updated = siphash24_finalize(&state); - if (ret_new) - *ret_new = updated; - if (updated != timestamp_hash) - log_debug("Modification times have changed, need to update cache."); - return updated == timestamp_hash; -} - -int unit_file_build_name_map( - const LookupPaths *lp, - uint64_t *cache_timestamp_hash, - Hashmap **unit_ids_map, - Hashmap **unit_names_map, - Set **path_cache) { - - /* Build two mappings: any name → main unit (i.e. the end result of symlink resolution), unit name → - * all aliases (i.e. the entry for a given key is a a list of all names which point to this key). The - * key is included in the value iff we saw a file or symlink with that name. In other words, if we - * have a key, but it is not present in the value for itself, there was an alias pointing to it, but - * the unit itself is not loadable. - * - * At the same, build a cache of paths where to find units. The non-const parameters are for input - * and output. Existing contents will be freed before the new contents are stored. - */ - - _cleanup_hashmap_free_ Hashmap *ids = NULL, *names = NULL; - _cleanup_set_free_free_ Set *paths = NULL; - uint64_t timestamp_hash; - char **dir; - int r; - - /* Before doing anything, check if the timestamp hash that was passed is still valid. - * If yes, do nothing. */ - if (cache_timestamp_hash && - lookup_paths_timestamp_hash_same(lp, *cache_timestamp_hash, ×tamp_hash)) - return 0; - - /* The timestamp hash is now set based on the mtimes from before when we start reading files. - * If anything is modified concurrently, we'll consider the cache outdated. */ - - if (path_cache) { - paths = set_new(&path_hash_ops_free); - if (!paths) - return log_oom(); - } - - STRV_FOREACH(dir, (char**) lp->search_path) { - struct dirent *de; - _cleanup_closedir_ DIR *d = NULL; - - d = opendir(*dir); - if (!d) { - if (errno != ENOENT) - log_warning_errno(errno, "Failed to open \"%s\", ignoring: %m", *dir); - continue; - } - - FOREACH_DIRENT_ALL(de, d, log_warning_errno(errno, "Failed to read \"%s\", ignoring: %m", *dir)) { - char *filename; - _cleanup_free_ char *_filename_free = NULL, *simplified = NULL; - const char *suffix, *dst = NULL; - bool valid_unit_name; - - valid_unit_name = unit_name_is_valid(de->d_name, UNIT_NAME_ANY); - - /* We only care about valid units and dirs with certain suffixes, let's ignore the - * rest. */ - if (!valid_unit_name && - !ENDSWITH_SET(de->d_name, ".wants", ".requires", ".d")) - continue; - - filename = path_join(*dir, de->d_name); - if (!filename) - return log_oom(); - - if (paths) { - r = set_consume(paths, filename); - if (r < 0) - return log_oom(); - /* We will still use filename below. This is safe because we know the set - * holds a reference. */ - } else - _filename_free = filename; /* Make sure we free the filename. */ - - if (!valid_unit_name) - continue; - assert_se(suffix = strrchr(de->d_name, '.')); - - /* search_path is ordered by priority (highest first). If the name is already mapped - * to something (incl. itself), it means that we have already seen it, and we should - * ignore it here. */ - if (hashmap_contains(ids, de->d_name)) - continue; - - dirent_ensure_type(d, de); - if (de->d_type == DT_LNK) { - /* We don't explicitly check for alias loops here. unit_ids_map_get() which - * limits the number of hops should be used to access the map. */ - - _cleanup_free_ char *target = NULL; - - r = readlinkat_malloc(dirfd(d), de->d_name, &target); - if (r < 0) { - log_warning_errno(r, "Failed to read symlink %s/%s, ignoring: %m", - *dir, de->d_name); - continue; - } - - const bool is_abs = path_is_absolute(target); - if (lp->root_dir || !is_abs) { - char *target_abs = path_join(is_abs ? lp->root_dir : *dir, target); - if (!target_abs) - return log_oom(); - - free_and_replace(target, target_abs); - } - - /* Get rid of "." and ".." components in target path */ - r = chase_symlinks(target, lp->root_dir, CHASE_NOFOLLOW | CHASE_NONEXISTENT, &simplified, NULL); - if (r < 0) { - log_warning_errno(r, "Failed to resolve symlink %s pointing to %s, ignoring: %m", - filename, target); - continue; - } - - /* Check if the symlink goes outside of our search path. - * If yes, it's a linked unit file or mask, and we don't care about the target name. - * Let's just store the link destination directly. - * If not, let's verify that it's a good symlink. */ - char *tail = path_startswith_strv(simplified, lp->search_path); - if (tail) { - bool self_alias; - - dst = basename(simplified); - self_alias = streq(dst, de->d_name); - - if (is_path(tail)) - log_full(self_alias ? LOG_DEBUG : LOG_WARNING, - "Suspicious symlink %s→%s, treating as alias.", - filename, simplified); - - r = unit_validate_alias_symlink_and_warn(filename, simplified); - if (r < 0) - continue; - - if (self_alias) { - /* A self-alias that has no effect */ - log_debug("%s: self-alias: %s/%s → %s, ignoring.", - __func__, *dir, de->d_name, dst); - continue; - } - - log_debug("%s: alias: %s/%s → %s", __func__, *dir, de->d_name, dst); - } else { - dst = simplified; - - log_debug("%s: linked unit file: %s/%s → %s", __func__, *dir, de->d_name, dst); - } - - } else { - dst = filename; - log_debug("%s: normal unit file: %s", __func__, dst); - } - - r = hashmap_put_strdup(&ids, de->d_name, dst); - if (r < 0) - return log_warning_errno(r, "Failed to add entry to hashmap (%s→%s): %m", - de->d_name, dst); - } - } - - /* Let's also put the names in the reverse db. */ - const char *dummy, *src; - HASHMAP_FOREACH_KEY(dummy, src, ids) { - const char *dst; - - r = unit_ids_map_get(ids, src, &dst); - if (r < 0) - continue; - - if (null_or_empty_path(dst) != 0) - continue; - - /* Do not treat instance symlinks that point to the template as aliases */ - if (unit_name_is_valid(basename(dst), UNIT_NAME_TEMPLATE) && - unit_name_is_valid(src, UNIT_NAME_INSTANCE)) - continue; - - r = string_strv_hashmap_put(&names, basename(dst), src); - if (r < 0) - return log_warning_errno(r, "Failed to add entry to hashmap (%s→%s): %m", - basename(dst), src); - } - - if (cache_timestamp_hash) - *cache_timestamp_hash = timestamp_hash; - - hashmap_free_and_replace(*unit_ids_map, ids); - hashmap_free_and_replace(*unit_names_map, names); - if (path_cache) - set_free_and_replace(*path_cache, paths); - - return 1; -} - -int unit_file_find_fragment( - Hashmap *unit_ids_map, - Hashmap *unit_name_map, - const char *unit_name, - const char **ret_fragment_path, - Set **ret_names) { - - const char *fragment = NULL; - _cleanup_free_ char *template = NULL, *instance = NULL; - _cleanup_set_free_free_ Set *names = NULL; - char **t, **nnn; - int r, name_type; - - /* Finds a fragment path, and returns the set of names: - * if we have …/foo.service and …/foo-alias.service→foo.service, - * and …/foo@.service and …/foo-alias@.service→foo@.service, - * and …/foo@inst.service, - * this should return: - * foo.service → …/foo.service, {foo.service, foo-alias.service}, - * foo-alias.service → …/foo.service, {foo.service, foo-alias.service}, - * foo@.service → …/foo@.service, {foo@.service, foo-alias@.service}, - * foo-alias@.service → …/foo@.service, {foo@.service, foo-alias@.service}, - * foo@bar.service → …/foo@.service, {foo@bar.service, foo-alias@bar.service}, - * foo-alias@bar.service → …/foo@.service, {foo@bar.service, foo-alias@bar.service}, - * foo-alias@inst.service → …/foo@inst.service, {foo@inst.service, foo-alias@inst.service}. - */ - - name_type = unit_name_to_instance(unit_name, &instance); - if (name_type < 0) - return name_type; - - names = set_new(&string_hash_ops); - if (!names) - return -ENOMEM; - - /* The unit always has its own name if it's not a template. */ - if (IN_SET(name_type, UNIT_NAME_PLAIN, UNIT_NAME_INSTANCE)) { - r = set_put_strdup(&names, unit_name); - if (r < 0) - return r; - } - - /* First try to load fragment under the original name */ - r = unit_ids_map_get(unit_ids_map, unit_name, &fragment); - if (r < 0 && !IN_SET(r, -ENOENT, -ENXIO)) - return log_debug_errno(r, "Cannot load unit %s: %m", unit_name); - - if (fragment) { - /* Add any aliases of the original name to the set of names */ - nnn = hashmap_get(unit_name_map, basename(fragment)); - STRV_FOREACH(t, nnn) { - if (name_type == UNIT_NAME_INSTANCE && unit_name_is_valid(*t, UNIT_NAME_TEMPLATE)) { - char *inst; - - r = unit_name_replace_instance(*t, instance, &inst); - if (r < 0) - return log_debug_errno(r, "Cannot build instance name %s+%s: %m", *t, instance); - - if (!streq(unit_name, inst)) - log_debug("%s: %s has alias %s", __func__, unit_name, inst); - - log_info("%s: %s+%s → %s", __func__, *t, instance, inst); - r = set_consume(names, inst); - } else { - if (!streq(unit_name, *t)) - log_debug("%s: %s has alias %s", __func__, unit_name, *t); - - r = set_put_strdup(&names, *t); - } - if (r < 0) - return r; - } - } - - if (!fragment && name_type == UNIT_NAME_INSTANCE) { - /* Look for a fragment under the template name */ - - r = unit_name_template(unit_name, &template); - if (r < 0) - return log_debug_errno(r, "Failed to determine template name: %m"); - - r = unit_ids_map_get(unit_ids_map, template, &fragment); - if (r < 0 && !IN_SET(r, -ENOENT, -ENXIO)) - return log_debug_errno(r, "Cannot load template %s: %m", template); - - if (fragment) { - /* Add any aliases of the original name to the set of names */ - nnn = hashmap_get(unit_name_map, basename(fragment)); - STRV_FOREACH(t, nnn) { - _cleanup_free_ char *inst = NULL; - const char *inst_fragment = NULL; - - r = unit_name_replace_instance(*t, instance, &inst); - if (r < 0) - return log_debug_errno(r, "Cannot build instance name %s+%s: %m", template, instance); - - /* Exclude any aliases that point in some other direction. */ - r = unit_ids_map_get(unit_ids_map, inst, &inst_fragment); - if (r < 0 && !IN_SET(r, -ENOENT, -ENXIO)) - return log_debug_errno(r, "Cannot find instance fragment %s: %m", inst); - - if (inst_fragment && - !streq(basename(inst_fragment), basename(fragment))) { - log_debug("Instance %s has fragment %s and is not an alias of %s.", - inst, inst_fragment, unit_name); - continue; - } - - if (!streq(unit_name, inst)) - log_debug("%s: %s has alias %s", __func__, unit_name, inst); - r = set_consume(names, TAKE_PTR(inst)); - if (r < 0) - return r; - } - } - } - - *ret_fragment_path = fragment; - *ret_names = TAKE_PTR(names); - - // FIXME: if instance, consider any unit names with different template name - return 0; -} - -static const char * const rlmap[] = { - "emergency", SPECIAL_EMERGENCY_TARGET, - "-b", SPECIAL_EMERGENCY_TARGET, - "rescue", SPECIAL_RESCUE_TARGET, - "single", SPECIAL_RESCUE_TARGET, - "-s", SPECIAL_RESCUE_TARGET, - "s", SPECIAL_RESCUE_TARGET, - "S", SPECIAL_RESCUE_TARGET, - "1", SPECIAL_RESCUE_TARGET, - "2", SPECIAL_MULTI_USER_TARGET, - "3", SPECIAL_MULTI_USER_TARGET, - "4", SPECIAL_MULTI_USER_TARGET, - "5", SPECIAL_GRAPHICAL_TARGET, - NULL -}; - -static const char * const rlmap_initrd[] = { - "emergency", SPECIAL_EMERGENCY_TARGET, - "rescue", SPECIAL_RESCUE_TARGET, - NULL -}; - -const char* runlevel_to_target(const char *word) { - const char * const *rlmap_ptr; - size_t i; - - if (!word) - return NULL; - - if (in_initrd()) { - word = startswith(word, "rd."); - if (!word) - return NULL; - } - - rlmap_ptr = in_initrd() ? rlmap_initrd : rlmap; - - for (i = 0; rlmap_ptr[i]; i += 2) - if (streq(word, rlmap_ptr[i])) - return rlmap_ptr[i+1]; - - return NULL; -} diff --git a/src/shared/unit-file.h b/src/shared/unit-file.h deleted file mode 100644 index 5463b0ab13..0000000000 --- a/src/shared/unit-file.h +++ /dev/null @@ -1,61 +0,0 @@ -/* SPDX-License-Identifier: LGPL-2.1-or-later */ -#pragma once - -#include - -#include "hashmap.h" -#include "time-util.h" -#include "unit-name.h" - -typedef enum UnitFileState UnitFileState; -typedef enum UnitFileScope UnitFileScope; -typedef struct LookupPaths LookupPaths; - -enum UnitFileState { - UNIT_FILE_ENABLED, - UNIT_FILE_ENABLED_RUNTIME, - UNIT_FILE_LINKED, - UNIT_FILE_LINKED_RUNTIME, - UNIT_FILE_ALIAS, - UNIT_FILE_MASKED, - UNIT_FILE_MASKED_RUNTIME, - UNIT_FILE_STATIC, - UNIT_FILE_DISABLED, - UNIT_FILE_INDIRECT, - UNIT_FILE_GENERATED, - UNIT_FILE_TRANSIENT, - UNIT_FILE_BAD, - _UNIT_FILE_STATE_MAX, - _UNIT_FILE_STATE_INVALID = -1 -}; - -enum UnitFileScope { - UNIT_FILE_SYSTEM, - UNIT_FILE_GLOBAL, - UNIT_FILE_USER, - _UNIT_FILE_SCOPE_MAX, - _UNIT_FILE_SCOPE_INVALID = -1 -}; - -bool unit_type_may_alias(UnitType type) _const_; -bool unit_type_may_template(UnitType type) _const_; - -int unit_symlink_name_compatible(const char *symlink, const char *target, bool instance_propagation); -int unit_validate_alias_symlink_and_warn(const char *filename, const char *target); - -bool lookup_paths_timestamp_hash_same(const LookupPaths *lp, uint64_t timestamp_hash, uint64_t *ret_new); -int unit_file_build_name_map( - const LookupPaths *lp, - uint64_t *cache_timestamp_hash, - Hashmap **unit_ids_map, - Hashmap **unit_names_map, - Set **path_cache); - -int unit_file_find_fragment( - Hashmap *unit_ids_map, - Hashmap *unit_name_map, - const char *unit_name, - const char **ret_fragment_path, - Set **ret_names); - -const char* runlevel_to_target(const char *rl);