diff options
Diffstat (limited to 'src/shared/userdb.c')
| -rw-r--r-- | src/shared/userdb.c | 1471 |
1 files changed, 1471 insertions, 0 deletions
diff --git a/src/shared/userdb.c b/src/shared/userdb.c new file mode 100644 index 0000000..4974ad0 --- /dev/null +++ b/src/shared/userdb.c @@ -0,0 +1,1471 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <sys/auxv.h> + +#include "conf-files.h" +#include "dirent-util.h" +#include "dlfcn-util.h" +#include "errno-util.h" +#include "fd-util.h" +#include "format-util.h" +#include "missing_syscall.h" +#include "parse-util.h" +#include "set.h" +#include "socket-util.h" +#include "strv.h" +#include "user-record-nss.h" +#include "user-util.h" +#include "userdb-dropin.h" +#include "userdb.h" +#include "varlink.h" + +DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(link_hash_ops, void, trivial_hash_func, trivial_compare_func, Varlink, varlink_unref); + +typedef enum LookupWhat { + LOOKUP_USER, + LOOKUP_GROUP, + LOOKUP_MEMBERSHIP, + _LOOKUP_WHAT_MAX, +} LookupWhat; + +struct UserDBIterator { + LookupWhat what; + UserDBFlags flags; + Set *links; + bool nss_covered:1; + bool nss_iterating:1; + bool dropin_covered:1; + bool synthesize_root:1; + bool synthesize_nobody:1; + bool nss_systemd_blocked:1; + char **dropins; + size_t current_dropin; + int error; + unsigned n_found; + sd_event *event; + UserRecord *found_user; /* when .what == LOOKUP_USER */ + GroupRecord *found_group; /* when .what == LOOKUP_GROUP */ + + char *found_user_name, *found_group_name; /* when .what == LOOKUP_MEMBERSHIP */ + char **members_of_group; + size_t index_members_of_group; + char *filter_user_name, *filter_group_name; +}; + +UserDBIterator* userdb_iterator_free(UserDBIterator *iterator) { + if (!iterator) + return NULL; + + set_free(iterator->links); + strv_free(iterator->dropins); + + switch (iterator->what) { + + case LOOKUP_USER: + user_record_unref(iterator->found_user); + + if (iterator->nss_iterating) + endpwent(); + + break; + + case LOOKUP_GROUP: + group_record_unref(iterator->found_group); + + if (iterator->nss_iterating) + endgrent(); + + break; + + case LOOKUP_MEMBERSHIP: + free(iterator->found_user_name); + free(iterator->found_group_name); + strv_free(iterator->members_of_group); + free(iterator->filter_user_name); + free(iterator->filter_group_name); + + if (iterator->nss_iterating) + endgrent(); + + break; + + default: + assert_not_reached(); + } + + sd_event_unref(iterator->event); + + if (iterator->nss_systemd_blocked) + assert_se(userdb_block_nss_systemd(false) >= 0); + + return mfree(iterator); +} + +static UserDBIterator* userdb_iterator_new(LookupWhat what, UserDBFlags flags) { + UserDBIterator *i; + + assert(what >= 0); + assert(what < _LOOKUP_WHAT_MAX); + + i = new(UserDBIterator, 1); + if (!i) + return NULL; + + *i = (UserDBIterator) { + .what = what, + .flags = flags, + .synthesize_root = !FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE), + .synthesize_nobody = !FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE), + }; + + return i; +} + +static int userdb_iterator_block_nss_systemd(UserDBIterator *iterator) { + int r; + + assert(iterator); + + if (iterator->nss_systemd_blocked) + return 0; + + r = userdb_block_nss_systemd(true); + if (r < 0) + return r; + + iterator->nss_systemd_blocked = true; + return 1; +} + +struct user_group_data { + JsonVariant *record; + bool incomplete; +}; + +static void user_group_data_release(struct user_group_data *d) { + json_variant_unref(d->record); +} + +static int userdb_on_query_reply( + Varlink *link, + JsonVariant *parameters, + const char *error_id, + VarlinkReplyFlags flags, + void *userdata) { + + UserDBIterator *iterator = ASSERT_PTR(userdata); + int r; + + if (error_id) { + log_debug("Got lookup error: %s", error_id); + + if (STR_IN_SET(error_id, + "io.systemd.UserDatabase.NoRecordFound", + "io.systemd.UserDatabase.ConflictingRecordFound")) + r = -ESRCH; + else if (streq(error_id, "io.systemd.UserDatabase.ServiceNotAvailable")) + r = -EHOSTDOWN; + else if (streq(error_id, "io.systemd.UserDatabase.EnumerationNotSupported")) + r = -EOPNOTSUPP; + else if (streq(error_id, VARLINK_ERROR_TIMEOUT)) + r = -ETIMEDOUT; + else + r = -EIO; + + goto finish; + } + + switch (iterator->what) { + + case LOOKUP_USER: { + _cleanup_(user_group_data_release) struct user_group_data user_data = {}; + + static const JsonDispatch dispatch_table[] = { + { "record", _JSON_VARIANT_TYPE_INVALID, json_dispatch_variant, offsetof(struct user_group_data, record), 0 }, + { "incomplete", JSON_VARIANT_BOOLEAN, json_dispatch_boolean, offsetof(struct user_group_data, incomplete), 0 }, + {} + }; + _cleanup_(user_record_unrefp) UserRecord *hr = NULL; + + assert_se(!iterator->found_user); + + r = json_dispatch(parameters, dispatch_table, NULL, 0, &user_data); + if (r < 0) + goto finish; + + if (!user_data.record) { + r = log_debug_errno(SYNTHETIC_ERRNO(EIO), "Reply is missing record key"); + goto finish; + } + + hr = user_record_new(); + if (!hr) { + r = -ENOMEM; + goto finish; + } + + r = user_record_load(hr, user_data.record, USER_RECORD_LOAD_REFUSE_SECRET|USER_RECORD_PERMISSIVE); + if (r < 0) + goto finish; + + if (!hr->service) { + r = log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "User record does not carry service information, refusing."); + goto finish; + } + + hr->incomplete = user_data.incomplete; + + /* We match the root user by the name since the name is our primary key. We match the nobody + * use by UID though, since the name might differ on OSes */ + if (streq_ptr(hr->user_name, "root")) + iterator->synthesize_root = false; + if (hr->uid == UID_NOBODY) + iterator->synthesize_nobody = false; + + iterator->found_user = TAKE_PTR(hr); + iterator->n_found++; + + /* More stuff coming? then let's just exit cleanly here */ + if (FLAGS_SET(flags, VARLINK_REPLY_CONTINUES)) + return 0; + + /* Otherwise, let's remove this link and exit cleanly then */ + r = 0; + goto finish; + } + + case LOOKUP_GROUP: { + _cleanup_(user_group_data_release) struct user_group_data group_data = {}; + + static const JsonDispatch dispatch_table[] = { + { "record", _JSON_VARIANT_TYPE_INVALID, json_dispatch_variant, offsetof(struct user_group_data, record), 0 }, + { "incomplete", JSON_VARIANT_BOOLEAN, json_dispatch_boolean, offsetof(struct user_group_data, incomplete), 0 }, + {} + }; + _cleanup_(group_record_unrefp) GroupRecord *g = NULL; + + assert_se(!iterator->found_group); + + r = json_dispatch(parameters, dispatch_table, NULL, 0, &group_data); + if (r < 0) + goto finish; + + if (!group_data.record) { + r = log_debug_errno(SYNTHETIC_ERRNO(EIO), "Reply is missing record key"); + goto finish; + } + + g = group_record_new(); + if (!g) { + r = -ENOMEM; + goto finish; + } + + r = group_record_load(g, group_data.record, USER_RECORD_LOAD_REFUSE_SECRET|USER_RECORD_PERMISSIVE); + if (r < 0) + goto finish; + + if (!g->service) { + r = log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Group record does not carry service information, refusing."); + goto finish; + } + + g->incomplete = group_data.incomplete; + + if (streq_ptr(g->group_name, "root")) + iterator->synthesize_root = false; + if (g->gid == GID_NOBODY) + iterator->synthesize_nobody = false; + + iterator->found_group = TAKE_PTR(g); + iterator->n_found++; + + if (FLAGS_SET(flags, VARLINK_REPLY_CONTINUES)) + return 0; + + r = 0; + goto finish; + } + + case LOOKUP_MEMBERSHIP: { + struct membership_data { + const char *user_name; + const char *group_name; + } membership_data = {}; + + static const JsonDispatch dispatch_table[] = { + { "userName", JSON_VARIANT_STRING, json_dispatch_user_group_name, offsetof(struct membership_data, user_name), JSON_RELAX }, + { "groupName", JSON_VARIANT_STRING, json_dispatch_user_group_name, offsetof(struct membership_data, group_name), JSON_RELAX }, + {} + }; + + assert(!iterator->found_user_name); + assert(!iterator->found_group_name); + + r = json_dispatch(parameters, dispatch_table, NULL, 0, &membership_data); + if (r < 0) + goto finish; + + iterator->found_user_name = mfree(iterator->found_user_name); + iterator->found_group_name = mfree(iterator->found_group_name); + + iterator->found_user_name = strdup(membership_data.user_name); + if (!iterator->found_user_name) { + r = -ENOMEM; + goto finish; + } + + iterator->found_group_name = strdup(membership_data.group_name); + if (!iterator->found_group_name) { + r = -ENOMEM; + goto finish; + } + + iterator->n_found++; + + if (FLAGS_SET(flags, VARLINK_REPLY_CONTINUES)) + return 0; + + r = 0; + goto finish; + } + + default: + assert_not_reached(); + } + +finish: + /* If we got one ESRCH, let that win. This way when we do a wild dump we won't be tripped up by bad + * errors if at least one connection ended cleanly */ + if (r == -ESRCH || iterator->error == 0) + iterator->error = -r; + + assert_se(set_remove(iterator->links, link) == link); + link = varlink_unref(link); + return 0; +} + +static int userdb_connect( + UserDBIterator *iterator, + const char *path, + const char *method, + bool more, + JsonVariant *query) { + + _cleanup_(varlink_unrefp) Varlink *vl = NULL; + int r; + + assert(iterator); + assert(path); + assert(method); + + r = varlink_connect_address(&vl, path); + if (r < 0) + return log_debug_errno(r, "Unable to connect to %s: %m", path); + + varlink_set_userdata(vl, iterator); + + if (!iterator->event) { + r = sd_event_new(&iterator->event); + if (r < 0) + return log_debug_errno(r, "Unable to allocate event loop: %m"); + } + + r = varlink_attach_event(vl, iterator->event, SD_EVENT_PRIORITY_NORMAL); + if (r < 0) + return log_debug_errno(r, "Failed to attach varlink connection to event loop: %m"); + + (void) varlink_set_description(vl, path); + + r = varlink_bind_reply(vl, userdb_on_query_reply); + if (r < 0) + return log_debug_errno(r, "Failed to bind reply callback: %m"); + + if (more) + r = varlink_observe(vl, method, query); + else + r = varlink_invoke(vl, method, query); + if (r < 0) + return log_debug_errno(r, "Failed to invoke varlink method: %m"); + + r = set_ensure_consume(&iterator->links, &link_hash_ops, TAKE_PTR(vl)); + if (r < 0) + return log_debug_errno(r, "Failed to add varlink connection to set: %m"); + return r; +} + +static int userdb_start_query( + UserDBIterator *iterator, + const char *method, + bool more, + JsonVariant *query, + UserDBFlags flags) { + + _cleanup_(strv_freep) char **except = NULL, **only = NULL; + _cleanup_(closedirp) DIR *d = NULL; + const char *e; + int r, ret = 0; + + assert(iterator); + assert(method); + + if (FLAGS_SET(flags, USERDB_EXCLUDE_VARLINK)) + return -ENOLINK; + + e = getenv("SYSTEMD_BYPASS_USERDB"); + if (e) { + r = parse_boolean(e); + if (r > 0) + return -ENOLINK; + if (r < 0) { + except = strv_split(e, ":"); + if (!except) + return -ENOMEM; + } + } + + e = getenv("SYSTEMD_ONLY_USERDB"); + if (e) { + only = strv_split(e, ":"); + if (!only) + return -ENOMEM; + } + + /* First, let's talk to the multiplexer, if we can */ + if ((flags & (USERDB_AVOID_MULTIPLEXER|USERDB_EXCLUDE_DYNAMIC_USER|USERDB_EXCLUDE_NSS|USERDB_EXCLUDE_DROPIN|USERDB_DONT_SYNTHESIZE)) == 0 && + !strv_contains(except, "io.systemd.Multiplexer") && + (!only || strv_contains(only, "io.systemd.Multiplexer"))) { + _cleanup_(json_variant_unrefp) JsonVariant *patched_query = json_variant_ref(query); + + r = json_variant_set_field_string(&patched_query, "service", "io.systemd.Multiplexer"); + if (r < 0) + return log_debug_errno(r, "Unable to set service JSON field: %m"); + + r = userdb_connect(iterator, "/run/systemd/userdb/io.systemd.Multiplexer", method, more, patched_query); + if (r >= 0) { + iterator->nss_covered = true; /* The multiplexer does NSS */ + iterator->dropin_covered = true; /* It also handles drop-in stuff */ + return 0; + } + } + + d = opendir("/run/systemd/userdb/"); + if (!d) { + if (errno == ENOENT) + return -ESRCH; + + return -errno; + } + + FOREACH_DIRENT(de, d, return -errno) { + _cleanup_(json_variant_unrefp) JsonVariant *patched_query = NULL; + _cleanup_free_ char *p = NULL; + bool is_nss, is_dropin; + + if (streq(de->d_name, "io.systemd.Multiplexer")) /* We already tried this above, don't try this again */ + continue; + + if (FLAGS_SET(flags, USERDB_EXCLUDE_DYNAMIC_USER) && + streq(de->d_name, "io.systemd.DynamicUser")) + continue; + + /* Avoid NSS is this is requested. Note that we also skip NSS when we were asked to skip the + * multiplexer, since in that case it's safer to do NSS in the client side emulation below + * (and when we run as part of systemd-userdbd.service we don't want to talk to ourselves + * anyway). */ + is_nss = streq(de->d_name, "io.systemd.NameServiceSwitch"); + if ((flags & (USERDB_EXCLUDE_NSS|USERDB_AVOID_MULTIPLEXER)) && is_nss) + continue; + + /* Similar for the drop-in service */ + is_dropin = streq(de->d_name, "io.systemd.DropIn"); + if ((flags & (USERDB_EXCLUDE_DROPIN|USERDB_AVOID_MULTIPLEXER)) && is_dropin) + continue; + + if (strv_contains(except, de->d_name)) + continue; + + if (only && !strv_contains(only, de->d_name)) + continue; + + p = path_join("/run/systemd/userdb/", de->d_name); + if (!p) + return -ENOMEM; + + patched_query = json_variant_ref(query); + r = json_variant_set_field_string(&patched_query, "service", de->d_name); + if (r < 0) + return log_debug_errno(r, "Unable to set service JSON field: %m"); + + r = userdb_connect(iterator, p, method, more, patched_query); + if (is_nss && r >= 0) /* Turn off fallback NSS + dropin if we found the NSS/dropin service + * and could connect to it */ + iterator->nss_covered = true; + if (is_dropin && r >= 0) + iterator->dropin_covered = true; + + if (ret == 0 && r < 0) + ret = r; + } + + if (set_isempty(iterator->links)) + return ret < 0 ? ret : -ESRCH; /* propagate last error we saw if we couldn't connect to anything. */ + + /* We connected to some services, in this case, ignore the ones we failed on */ + return 0; +} + +static int userdb_process( + UserDBIterator *iterator, + UserRecord **ret_user_record, + GroupRecord **ret_group_record, + char **ret_user_name, + char **ret_group_name) { + + int r; + + assert(iterator); + + for (;;) { + if (iterator->what == LOOKUP_USER && iterator->found_user) { + if (ret_user_record) + *ret_user_record = TAKE_PTR(iterator->found_user); + else + iterator->found_user = user_record_unref(iterator->found_user); + + if (ret_group_record) + *ret_group_record = NULL; + if (ret_user_name) + *ret_user_name = NULL; + if (ret_group_name) + *ret_group_name = NULL; + + return 0; + } + + if (iterator->what == LOOKUP_GROUP && iterator->found_group) { + if (ret_group_record) + *ret_group_record = TAKE_PTR(iterator->found_group); + else + iterator->found_group = group_record_unref(iterator->found_group); + + if (ret_user_record) + *ret_user_record = NULL; + if (ret_user_name) + *ret_user_name = NULL; + if (ret_group_name) + *ret_group_name = NULL; + + return 0; + } + + if (iterator->what == LOOKUP_MEMBERSHIP && iterator->found_user_name && iterator->found_group_name) { + if (ret_user_name) + *ret_user_name = TAKE_PTR(iterator->found_user_name); + else + iterator->found_user_name = mfree(iterator->found_user_name); + + if (ret_group_name) + *ret_group_name = TAKE_PTR(iterator->found_group_name); + else + iterator->found_group_name = mfree(iterator->found_group_name); + + if (ret_user_record) + *ret_user_record = NULL; + if (ret_group_record) + *ret_group_record = NULL; + + return 0; + } + + if (set_isempty(iterator->links)) { + if (iterator->error == 0) + return -ESRCH; + + return -abs(iterator->error); + } + + if (!iterator->event) + return -ESRCH; + + r = sd_event_run(iterator->event, UINT64_MAX); + if (r < 0) + return r; + } +} + +static int synthetic_root_user_build(UserRecord **ret) { + return user_record_build( + ret, + JSON_BUILD_OBJECT(JSON_BUILD_PAIR("userName", JSON_BUILD_CONST_STRING("root")), + JSON_BUILD_PAIR("uid", JSON_BUILD_UNSIGNED(0)), + JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(0)), + JSON_BUILD_PAIR("homeDirectory", JSON_BUILD_CONST_STRING("/root")), + JSON_BUILD_PAIR("disposition", JSON_BUILD_CONST_STRING("intrinsic")))); +} + +static int synthetic_nobody_user_build(UserRecord **ret) { + return user_record_build( + ret, + JSON_BUILD_OBJECT(JSON_BUILD_PAIR("userName", JSON_BUILD_CONST_STRING(NOBODY_USER_NAME)), + JSON_BUILD_PAIR("uid", JSON_BUILD_UNSIGNED(UID_NOBODY)), + JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(GID_NOBODY)), + JSON_BUILD_PAIR("shell", JSON_BUILD_CONST_STRING(NOLOGIN)), + JSON_BUILD_PAIR("locked", JSON_BUILD_BOOLEAN(true)), + JSON_BUILD_PAIR("disposition", JSON_BUILD_CONST_STRING("intrinsic")))); +} + +int userdb_by_name(const char *name, UserDBFlags flags, UserRecord **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_(json_variant_unrefp) JsonVariant *query = NULL; + int r; + + if (!valid_user_group_name(name, VALID_USER_RELAX)) + return -EINVAL; + + r = json_build(&query, JSON_BUILD_OBJECT( + JSON_BUILD_PAIR("userName", JSON_BUILD_STRING(name)))); + if (r < 0) + return r; + + iterator = userdb_iterator_new(LOOKUP_USER, flags); + if (!iterator) + return -ENOMEM; + + r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetUserRecord", false, query, flags); + if (r >= 0) { + r = userdb_process(iterator, ret, NULL, NULL, NULL); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && !iterator->dropin_covered) { + r = dropin_user_record_by_name(name, NULL, flags, ret); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && !iterator->nss_covered) { + /* Make sure the NSS lookup doesn't recurse back to us. */ + + r = userdb_iterator_block_nss_systemd(iterator); + if (r >= 0) { + /* Client-side NSS fallback */ + r = nss_user_record_by_name(name, !FLAGS_SET(flags, USERDB_SUPPRESS_SHADOW), ret); + if (r >= 0) + return r; + } + } + + if (!FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE)) { + if (streq(name, "root")) + return synthetic_root_user_build(ret); + + if (streq(name, NOBODY_USER_NAME) && synthesize_nobody()) + return synthetic_nobody_user_build(ret); + } + + return r; +} + +int userdb_by_uid(uid_t uid, UserDBFlags flags, UserRecord **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_(json_variant_unrefp) JsonVariant *query = NULL; + int r; + + if (!uid_is_valid(uid)) + return -EINVAL; + + r = json_build(&query, JSON_BUILD_OBJECT( + JSON_BUILD_PAIR("uid", JSON_BUILD_UNSIGNED(uid)))); + if (r < 0) + return r; + + iterator = userdb_iterator_new(LOOKUP_USER, flags); + if (!iterator) + return -ENOMEM; + + r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetUserRecord", false, query, flags); + if (r >= 0) { + r = userdb_process(iterator, ret, NULL, NULL, NULL); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && !iterator->dropin_covered) { + r = dropin_user_record_by_uid(uid, NULL, flags, ret); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && !iterator->nss_covered) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r >= 0) { + /* Client-side NSS fallback */ + r = nss_user_record_by_uid(uid, !FLAGS_SET(flags, USERDB_SUPPRESS_SHADOW), ret); + if (r >= 0) + return r; + } + } + + if (!FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE)) { + if (uid == 0) + return synthetic_root_user_build(ret); + + if (uid == UID_NOBODY && synthesize_nobody()) + return synthetic_nobody_user_build(ret); + } + + return r; +} + +int userdb_all(UserDBFlags flags, UserDBIterator **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + int r, qr; + + assert(ret); + + iterator = userdb_iterator_new(LOOKUP_USER, flags); + if (!iterator) + return -ENOMEM; + + qr = userdb_start_query(iterator, "io.systemd.UserDatabase.GetUserRecord", true, NULL, flags); + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && (qr < 0 || !iterator->nss_covered)) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r < 0) + return r; + + setpwent(); + iterator->nss_iterating = true; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && (qr < 0 || !iterator->dropin_covered)) { + r = conf_files_list_nulstr( + &iterator->dropins, + ".user", + NULL, + CONF_FILES_REGULAR|CONF_FILES_FILTER_MASKED, + USERDB_DROPIN_DIR_NULSTR("userdb")); + if (r < 0) + log_debug_errno(r, "Failed to find user drop-ins, ignoring: %m"); + } + + /* propagate IPC error, but only if there are no drop-ins */ + if (qr < 0 && + !iterator->nss_iterating && + strv_isempty(iterator->dropins)) + return qr; + + *ret = TAKE_PTR(iterator); + return 0; +} + +int userdb_iterator_get(UserDBIterator *iterator, UserRecord **ret) { + int r; + + assert(iterator); + assert(iterator->what == LOOKUP_USER); + + if (iterator->nss_iterating) { + struct passwd *pw; + + /* If NSS isn't covered elsewhere, let's iterate through it first, since it probably contains + * the more traditional sources, which are probably good to show first. */ + + pw = getpwent(); + if (pw) { + _cleanup_free_ char *buffer = NULL; + bool incomplete = false; + struct spwd spwd; + + if (streq_ptr(pw->pw_name, "root")) + iterator->synthesize_root = false; + if (pw->pw_uid == UID_NOBODY) + iterator->synthesize_nobody = false; + + if (!FLAGS_SET(iterator->flags, USERDB_SUPPRESS_SHADOW)) { + r = nss_spwd_for_passwd(pw, &spwd, &buffer); + if (r < 0) { + log_debug_errno(r, "Failed to acquire shadow entry for user %s, ignoring: %m", pw->pw_name); + incomplete = ERRNO_IS_PRIVILEGE(r); + } + } else { + r = -EUCLEAN; + incomplete = true; + } + + r = nss_passwd_to_user_record(pw, r >= 0 ? &spwd : NULL, ret); + if (r < 0) + return r; + + if (ret) + (*ret)->incomplete = incomplete; + + iterator->n_found++; + return r; + } + + if (errno != 0) + log_debug_errno(errno, "Failure to iterate NSS user database, ignoring: %m"); + + iterator->nss_iterating = false; + endpwent(); + } + + for (; iterator->dropins && iterator->dropins[iterator->current_dropin]; iterator->current_dropin++) { + const char *i = iterator->dropins[iterator->current_dropin]; + _cleanup_free_ char *fn = NULL; + uid_t uid; + char *e; + + /* Next, let's add in the static drop-ins, which are quick to retrieve */ + + r = path_extract_filename(i, &fn); + if (r < 0) + return r; + + e = endswith(fn, ".user"); /* not actually a .user file? Then skip to next */ + if (!e) + continue; + + *e = 0; /* Chop off suffix */ + + if (parse_uid(fn, &uid) < 0) /* not a UID .user file? Then skip to next */ + continue; + + r = dropin_user_record_by_uid(uid, i, iterator->flags, ret); + if (r < 0) { + log_debug_errno(r, "Failed to parse user record for UID " UID_FMT ", ignoring: %m", uid); + continue; /* If we failed to parse this record, let's suppress it from enumeration, + * and continue with the next record. Maybe someone is dropping it files + * and only partially wrote this one. */ + } + + iterator->current_dropin++; /* make sure on the next call of userdb_iterator_get() we continue with the next dropin */ + iterator->n_found++; + return 0; + } + + /* Then, let's return the users provided by varlink IPC */ + r = userdb_process(iterator, ret, NULL, NULL, NULL); + if (r < 0) { + + /* Finally, synthesize root + nobody if not done yet */ + if (iterator->synthesize_root) { + iterator->synthesize_root = false; + iterator->n_found++; + return synthetic_root_user_build(ret); + } + + if (iterator->synthesize_nobody) { + iterator->synthesize_nobody = false; + iterator->n_found++; + return synthetic_nobody_user_build(ret); + } + + /* if we found at least one entry, then ignore errors and indicate that we reached the end */ + if (iterator->n_found > 0) + return -ESRCH; + } + + return r; +} + +static int synthetic_root_group_build(GroupRecord **ret) { + return group_record_build( + ret, + JSON_BUILD_OBJECT(JSON_BUILD_PAIR("groupName", JSON_BUILD_CONST_STRING("root")), + JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(0)), + JSON_BUILD_PAIR("disposition", JSON_BUILD_CONST_STRING("intrinsic")))); +} + +static int synthetic_nobody_group_build(GroupRecord **ret) { + return group_record_build( + ret, + JSON_BUILD_OBJECT(JSON_BUILD_PAIR("groupName", JSON_BUILD_CONST_STRING(NOBODY_GROUP_NAME)), + JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(GID_NOBODY)), + JSON_BUILD_PAIR("disposition", JSON_BUILD_CONST_STRING("intrinsic")))); +} + +int groupdb_by_name(const char *name, UserDBFlags flags, GroupRecord **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_(json_variant_unrefp) JsonVariant *query = NULL; + int r; + + if (!valid_user_group_name(name, VALID_USER_RELAX)) + return -EINVAL; + + r = json_build(&query, JSON_BUILD_OBJECT( + JSON_BUILD_PAIR("groupName", JSON_BUILD_STRING(name)))); + if (r < 0) + return r; + + iterator = userdb_iterator_new(LOOKUP_GROUP, flags); + if (!iterator) + return -ENOMEM; + + r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetGroupRecord", false, query, flags); + if (r >= 0) { + r = userdb_process(iterator, NULL, ret, NULL, NULL); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && !(iterator && iterator->dropin_covered)) { + r = dropin_group_record_by_name(name, NULL, flags, ret); + if (r >= 0) + return r; + } + + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && !(iterator && iterator->nss_covered)) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r >= 0) { + r = nss_group_record_by_name(name, !FLAGS_SET(flags, USERDB_SUPPRESS_SHADOW), ret); + if (r >= 0) + return r; + } + } + + if (!FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE)) { + if (streq(name, "root")) + return synthetic_root_group_build(ret); + + if (streq(name, NOBODY_GROUP_NAME) && synthesize_nobody()) + return synthetic_nobody_group_build(ret); + } + + return r; +} + +int groupdb_by_gid(gid_t gid, UserDBFlags flags, GroupRecord **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_(json_variant_unrefp) JsonVariant *query = NULL; + int r; + + if (!gid_is_valid(gid)) + return -EINVAL; + + r = json_build(&query, JSON_BUILD_OBJECT( + JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(gid)))); + if (r < 0) + return r; + + iterator = userdb_iterator_new(LOOKUP_GROUP, flags); + if (!iterator) + return -ENOMEM; + + r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetGroupRecord", false, query, flags); + if (r >= 0) { + r = userdb_process(iterator, NULL, ret, NULL, NULL); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && !(iterator && iterator->dropin_covered)) { + r = dropin_group_record_by_gid(gid, NULL, flags, ret); + if (r >= 0) + return r; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && !(iterator && iterator->nss_covered)) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r >= 0) { + r = nss_group_record_by_gid(gid, !FLAGS_SET(flags, USERDB_SUPPRESS_SHADOW), ret); + if (r >= 0) + return r; + } + } + + if (!FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE)) { + if (gid == 0) + return synthetic_root_group_build(ret); + + if (gid == GID_NOBODY && synthesize_nobody()) + return synthetic_nobody_group_build(ret); + } + + return r; +} + +int groupdb_all(UserDBFlags flags, UserDBIterator **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + int r, qr; + + assert(ret); + + iterator = userdb_iterator_new(LOOKUP_GROUP, flags); + if (!iterator) + return -ENOMEM; + + qr = userdb_start_query(iterator, "io.systemd.UserDatabase.GetGroupRecord", true, NULL, flags); + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && (qr < 0 || !iterator->nss_covered)) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r < 0) + return r; + + setgrent(); + iterator->nss_iterating = true; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && (qr < 0 || !iterator->dropin_covered)) { + r = conf_files_list_nulstr( + &iterator->dropins, + ".group", + NULL, + CONF_FILES_REGULAR|CONF_FILES_FILTER_MASKED, + USERDB_DROPIN_DIR_NULSTR("userdb")); + if (r < 0) + log_debug_errno(r, "Failed to find group drop-ins, ignoring: %m"); + } + + if (qr < 0 && + !iterator->nss_iterating && + strv_isempty(iterator->dropins)) + return qr; + + *ret = TAKE_PTR(iterator); + return 0; +} + +int groupdb_iterator_get(UserDBIterator *iterator, GroupRecord **ret) { + int r; + + assert(iterator); + assert(iterator->what == LOOKUP_GROUP); + + if (iterator->nss_iterating) { + struct group *gr; + + errno = 0; + gr = getgrent(); + if (gr) { + _cleanup_free_ char *buffer = NULL; + bool incomplete = false; + struct sgrp sgrp; + + if (streq_ptr(gr->gr_name, "root")) + iterator->synthesize_root = false; + if (gr->gr_gid == GID_NOBODY) + iterator->synthesize_nobody = false; + + if (!FLAGS_SET(iterator->flags, USERDB_SUPPRESS_SHADOW)) { + r = nss_sgrp_for_group(gr, &sgrp, &buffer); + if (r < 0) { + log_debug_errno(r, "Failed to acquire shadow entry for group %s, ignoring: %m", gr->gr_name); + incomplete = ERRNO_IS_PRIVILEGE(r); + } + } else { + r = -EUCLEAN; + incomplete = true; + } + + r = nss_group_to_group_record(gr, r >= 0 ? &sgrp : NULL, ret); + if (r < 0) + return r; + + if (ret) + (*ret)->incomplete = incomplete; + + iterator->n_found++; + return r; + } + + if (errno != 0) + log_debug_errno(errno, "Failure to iterate NSS group database, ignoring: %m"); + + iterator->nss_iterating = false; + endgrent(); + } + + for (; iterator->dropins && iterator->dropins[iterator->current_dropin]; iterator->current_dropin++) { + const char *i = iterator->dropins[iterator->current_dropin]; + _cleanup_free_ char *fn = NULL; + gid_t gid; + char *e; + + r = path_extract_filename(i, &fn); + if (r < 0) + return r; + + e = endswith(fn, ".group"); + if (!e) + continue; + + *e = 0; /* Chop off suffix */ + + if (parse_gid(fn, &gid) < 0) + continue; + + r = dropin_group_record_by_gid(gid, i, iterator->flags, ret); + if (r < 0) { + log_debug_errno(r, "Failed to parse group record for GID " GID_FMT ", ignoring: %m", gid); + continue; + } + + iterator->current_dropin++; + iterator->n_found++; + return 0; + } + + r = userdb_process(iterator, NULL, ret, NULL, NULL); + if (r < 0) { + if (iterator->synthesize_root) { + iterator->synthesize_root = false; + iterator->n_found++; + return synthetic_root_group_build(ret); + } + + if (iterator->synthesize_nobody) { + iterator->synthesize_nobody = false; + iterator->n_found++; + return synthetic_nobody_group_build(ret); + } + + /* if we found at least one entry, then ignore errors and indicate that we reached the end */ + if (iterator->n_found > 0) + return -ESRCH; + } + + return r; +} + +static void discover_membership_dropins(UserDBIterator *i, UserDBFlags flags) { + int r; + + r = conf_files_list_nulstr( + &i->dropins, + ".membership", + NULL, + CONF_FILES_REGULAR|CONF_FILES_BASENAME|CONF_FILES_FILTER_MASKED, + USERDB_DROPIN_DIR_NULSTR("userdb")); + if (r < 0) + log_debug_errno(r, "Failed to find membership drop-ins, ignoring: %m"); +} + +int membershipdb_by_user(const char *name, UserDBFlags flags, UserDBIterator **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_(json_variant_unrefp) JsonVariant *query = NULL; + int r, qr; + + assert(ret); + + if (!valid_user_group_name(name, VALID_USER_RELAX)) + return -EINVAL; + + r = json_build(&query, JSON_BUILD_OBJECT( + JSON_BUILD_PAIR("userName", JSON_BUILD_STRING(name)))); + if (r < 0) + return r; + + iterator = userdb_iterator_new(LOOKUP_MEMBERSHIP, flags); + if (!iterator) + return -ENOMEM; + + iterator->filter_user_name = strdup(name); + if (!iterator->filter_user_name) + return -ENOMEM; + + qr = userdb_start_query(iterator, "io.systemd.UserDatabase.GetMemberships", true, query, flags); + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && (qr < 0 || !iterator->nss_covered)) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r < 0) + return r; + + setgrent(); + iterator->nss_iterating = true; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && (qr < 0 || !iterator->dropin_covered)) + discover_membership_dropins(iterator, flags); + + if (qr < 0 && + !iterator->nss_iterating && + strv_isempty(iterator->dropins)) + return qr; + + *ret = TAKE_PTR(iterator); + return 0; +} + +int membershipdb_by_group(const char *name, UserDBFlags flags, UserDBIterator **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_(json_variant_unrefp) JsonVariant *query = NULL; + int r, qr; + + assert(ret); + + if (!valid_user_group_name(name, VALID_USER_RELAX)) + return -EINVAL; + + r = json_build(&query, JSON_BUILD_OBJECT( + JSON_BUILD_PAIR("groupName", JSON_BUILD_STRING(name)))); + if (r < 0) + return r; + + iterator = userdb_iterator_new(LOOKUP_MEMBERSHIP, flags); + if (!iterator) + return -ENOMEM; + + iterator->filter_group_name = strdup(name); + if (!iterator->filter_group_name) + return -ENOMEM; + + qr = userdb_start_query(iterator, "io.systemd.UserDatabase.GetMemberships", true, query, flags); + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && (qr < 0 || !iterator->nss_covered)) { + _cleanup_(group_record_unrefp) GroupRecord *gr = NULL; + + r = userdb_iterator_block_nss_systemd(iterator); + if (r < 0) + return r; + + /* We ignore all errors here, since the group might be defined by a userdb native service, and we queried them already above. */ + (void) nss_group_record_by_name(name, false, &gr); + if (gr) { + iterator->members_of_group = strv_copy(gr->members); + if (!iterator->members_of_group) + return -ENOMEM; + + iterator->index_members_of_group = 0; + + iterator->found_group_name = strdup(name); + if (!iterator->found_group_name) + return -ENOMEM; + } + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && (qr < 0 || !iterator->dropin_covered)) + discover_membership_dropins(iterator, flags); + + if (qr < 0 && + strv_isempty(iterator->members_of_group) && + strv_isempty(iterator->dropins)) + return qr; + + *ret = TAKE_PTR(iterator); + return 0; +} + +int membershipdb_all(UserDBFlags flags, UserDBIterator **ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + int r, qr; + + assert(ret); + + iterator = userdb_iterator_new(LOOKUP_MEMBERSHIP, flags); + if (!iterator) + return -ENOMEM; + + qr = userdb_start_query(iterator, "io.systemd.UserDatabase.GetMemberships", true, NULL, flags); + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_NSS) && (qr < 0 || !iterator->nss_covered)) { + r = userdb_iterator_block_nss_systemd(iterator); + if (r < 0) + return r; + + setgrent(); + iterator->nss_iterating = true; + } + + if (!FLAGS_SET(flags, USERDB_EXCLUDE_DROPIN) && (qr < 0 || !iterator->dropin_covered)) + discover_membership_dropins(iterator, flags); + + if (qr < 0 && + !iterator->nss_iterating && + strv_isempty(iterator->dropins)) + return qr; + + *ret = TAKE_PTR(iterator); + return 0; +} + +int membershipdb_iterator_get( + UserDBIterator *iterator, + char **ret_user, + char **ret_group) { + + int r; + + assert(iterator); + + for (;;) { + /* If we are iterating through NSS acquire a new group entry if we haven't acquired one yet. */ + if (!iterator->members_of_group) { + struct group *g; + + if (!iterator->nss_iterating) + break; + + assert(!iterator->found_user_name); + do { + errno = 0; + g = getgrent(); + if (!g) { + if (errno != 0) + log_debug_errno(errno, "Failure during NSS group iteration, ignoring: %m"); + break; + } + + } while (iterator->filter_user_name ? !strv_contains(g->gr_mem, iterator->filter_user_name) : + strv_isempty(g->gr_mem)); + + if (g) { + r = free_and_strdup(&iterator->found_group_name, g->gr_name); + if (r < 0) + return r; + + if (iterator->filter_user_name) + iterator->members_of_group = strv_new(iterator->filter_user_name); + else + iterator->members_of_group = strv_copy(g->gr_mem); + if (!iterator->members_of_group) + return -ENOMEM; + + iterator->index_members_of_group = 0; + } else { + iterator->nss_iterating = false; + endgrent(); + break; + } + } + + assert(iterator->found_group_name); + assert(iterator->members_of_group); + assert(!iterator->found_user_name); + + if (iterator->members_of_group[iterator->index_members_of_group]) { + _cleanup_free_ char *cu = NULL, *cg = NULL; + + if (ret_user) { + cu = strdup(iterator->members_of_group[iterator->index_members_of_group]); + if (!cu) + return -ENOMEM; + } + + if (ret_group) { + cg = strdup(iterator->found_group_name); + if (!cg) + return -ENOMEM; + } + + if (ret_user) + *ret_user = TAKE_PTR(cu); + + if (ret_group) + *ret_group = TAKE_PTR(cg); + + iterator->index_members_of_group++; + return 0; + } + + iterator->members_of_group = strv_free(iterator->members_of_group); + iterator->found_group_name = mfree(iterator->found_group_name); + } + + for (; iterator->dropins && iterator->dropins[iterator->current_dropin]; iterator->current_dropin++) { + const char *i = iterator->dropins[iterator->current_dropin], *e, *c; + _cleanup_free_ char *un = NULL, *gn = NULL; + + e = endswith(i, ".membership"); + if (!e) + continue; + + c = memchr(i, ':', e - i); + if (!c) + continue; + + un = strndup(i, c - i); + if (!un) + return -ENOMEM; + if (iterator->filter_user_name) { + if (!streq(un, iterator->filter_user_name)) + continue; + } else if (!valid_user_group_name(un, VALID_USER_RELAX)) + continue; + + c++; /* skip over ':' */ + gn = strndup(c, e - c); + if (!gn) + return -ENOMEM; + if (iterator->filter_group_name) { + if (!streq(gn, iterator->filter_group_name)) + continue; + } else if (!valid_user_group_name(gn, VALID_USER_RELAX)) + continue; + + iterator->current_dropin++; + iterator->n_found++; + + if (ret_user) + *ret_user = TAKE_PTR(un); + if (ret_group) + *ret_group = TAKE_PTR(gn); + + return 0; + } + + r = userdb_process(iterator, NULL, NULL, ret_user, ret_group); + if (r < 0 && iterator->n_found > 0) + return -ESRCH; + + return r; +} + +int membershipdb_by_group_strv(const char *name, UserDBFlags flags, char ***ret) { + _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; + _cleanup_strv_free_ char **members = NULL; + int r; + + assert(name); + assert(ret); + + r = membershipdb_by_group(name, flags, &iterator); + if (r < 0) + return r; + + for (;;) { + _cleanup_free_ char *user_name = NULL; + + r = membershipdb_iterator_get(iterator, &user_name, NULL); + if (r == -ESRCH) + break; + if (r < 0) + return r; + + r = strv_consume(&members, TAKE_PTR(user_name)); + if (r < 0) + return r; + } + + strv_sort(members); + strv_uniq(members); + + *ret = TAKE_PTR(members); + return 0; +} + +int userdb_block_nss_systemd(int b) { + _cleanup_(dlclosep) void *dl = NULL; + int (*call)(bool b); + + /* Note that we might be called from libnss_systemd.so.2 itself, but that should be fine, really. */ + + dl = dlopen(ROOTLIBDIR "/libnss_systemd.so.2", RTLD_LAZY|RTLD_NODELETE); + if (!dl) { + /* If the file isn't installed, don't complain loudly */ + log_debug("Failed to dlopen(libnss_systemd.so.2), ignoring: %s", dlerror()); + return 0; + } + + call = (int (*)(bool b)) dlsym(dl, "_nss_systemd_block"); + if (!call) + /* If the file is installed but lacks the symbol we expect, things are weird, let's complain */ + return log_debug_errno(SYNTHETIC_ERRNO(ELIBBAD), + "Unable to find symbol _nss_systemd_block in libnss_systemd.so.2: %s", dlerror()); + + return call(b); +} |