| /* SPDX-License-Identifier: LGPL-2.1+ */ |
| |
| #include <sys/auxv.h> |
| |
| #include "dirent-util.h" |
| #include "errno-util.h" |
| #include "fd-util.h" |
| #include "group-record-nss.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.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; |
| Set *links; |
| bool nss_covered:1; |
| bool nss_iterating:1; |
| bool synthesize_root:1; |
| bool synthesize_nobody:1; |
| int error; |
| int nss_lock; |
| 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; |
| }; |
| |
| UserDBIterator* userdb_iterator_free(UserDBIterator *iterator) { |
| if (!iterator) |
| return NULL; |
| |
| set_free(iterator->links); |
| |
| 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); |
| |
| if (iterator->nss_iterating) |
| endgrent(); |
| |
| break; |
| |
| default: |
| assert_not_reached("Unexpected state?"); |
| } |
| |
| sd_event_unref(iterator->event); |
| safe_close(iterator->nss_lock); |
| |
| return mfree(iterator); |
| } |
| |
| static UserDBIterator* userdb_iterator_new(LookupWhat what) { |
| UserDBIterator *i; |
| |
| assert(what >= 0); |
| assert(what < _LOOKUP_WHAT_MAX); |
| |
| i = new(UserDBIterator, 1); |
| if (!i) |
| return NULL; |
| |
| *i = (UserDBIterator) { |
| .what = what, |
| .nss_lock = -1, |
| }; |
| |
| return i; |
| } |
| |
| 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 = userdata; |
| int r; |
| |
| assert(iterator); |
| |
| 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, 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_const_string, offsetof(struct membership_data, user_name), JSON_SAFE }, |
| { "groupName", JSON_VARIANT_STRING, json_dispatch_const_string, offsetof(struct membership_data, group_name), JSON_SAFE }, |
| {} |
| }; |
| |
| 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("unexpected lookup"); |
| } |
| |
| 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_allocated(&iterator->links, &link_hash_ops); |
| if (r < 0) |
| return log_debug_errno(r, "Failed to allocate set: %m"); |
| |
| r = set_put(iterator->links, vl); |
| if (r < 0) |
| return log_debug_errno(r, "Failed to add varlink connection to set: %m"); |
| |
| TAKE_PTR(vl); |
| 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; |
| struct dirent *de; |
| const char *e; |
| int r, ret = 0; |
| |
| assert(iterator); |
| assert(method); |
| |
| 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_AVOID_DYNAMIC_USER|USERDB_AVOID_NSS|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 */ |
| 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; |
| |
| if (streq(de->d_name, "io.systemd.Multiplexer")) /* We already tried this above, don't try this again */ |
| continue; |
| |
| if (FLAGS_SET(flags, USERDB_AVOID_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_AVOID_NSS|USERDB_AVOID_MULTIPLEXER)) && is_nss) |
| 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 if we found the NSS service and could connect |
| * to it */ |
| iterator->nss_covered = true; |
| |
| if (ret == 0 && r < 0) |
| ret = r; |
| } |
| |
| if (set_isempty(iterator->links)) |
| return ret; /* 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_STRING("root")), |
| JSON_BUILD_PAIR("uid", JSON_BUILD_UNSIGNED(0)), |
| JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(0)), |
| JSON_BUILD_PAIR("homeDirectory", JSON_BUILD_STRING("/root")), |
| JSON_BUILD_PAIR("disposition", JSON_BUILD_STRING("intrinsic")))); |
| } |
| |
| static int synthetic_nobody_user_build(UserRecord **ret) { |
| return user_record_build( |
| ret, |
| JSON_BUILD_OBJECT(JSON_BUILD_PAIR("userName", JSON_BUILD_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_STRING(NOLOGIN)), |
| JSON_BUILD_PAIR("locked", JSON_BUILD_BOOLEAN(true)), |
| JSON_BUILD_PAIR("disposition", JSON_BUILD_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_compat(name)) |
| 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); |
| 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_AVOID_NSS) && !(iterator && iterator->nss_covered)) { |
| /* Make sure the NSS lookup doesn't recurse back to us. (EBUSY is fine here, it just means we |
| * already took the lock from our thread, which is totally OK.) */ |
| r = userdb_nss_compat_disable(); |
| if (r >= 0 || r == -EBUSY) { |
| iterator->nss_lock = r; |
| |
| /* Client-side NSS fallback */ |
| r = nss_user_record_by_name(name, 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); |
| 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_AVOID_NSS) && !(iterator && iterator->nss_covered)) { |
| r = userdb_nss_compat_disable(); |
| if (r >= 0 || r == -EBUSY) { |
| iterator->nss_lock = r; |
| |
| /* Client-side NSS fallback */ |
| r = nss_user_record_by_uid(uid, 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; |
| |
| assert(ret); |
| |
| iterator = userdb_iterator_new(LOOKUP_USER); |
| if (!iterator) |
| return -ENOMEM; |
| |
| iterator->synthesize_root = iterator->synthesize_nobody = !FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE); |
| |
| r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetUserRecord", true, NULL, flags); |
| |
| if (!FLAGS_SET(flags, USERDB_AVOID_NSS) && (r < 0 || !iterator->nss_covered)) { |
| iterator->nss_lock = userdb_nss_compat_disable(); |
| if (iterator->nss_lock < 0 && iterator->nss_lock != -EBUSY) |
| return iterator->nss_lock; |
| |
| setpwent(); |
| iterator->nss_iterating = true; |
| } else if (r < 0) |
| return r; |
| |
| *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; |
| |
| 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); |
| } |
| |
| r = nss_passwd_to_user_record(pw, r >= 0 ? &spwd : NULL, ret); |
| if (r < 0) |
| return r; |
| |
| if (ret) |
| (*ret)->incomplete = incomplete; |
| return r; |
| } |
| |
| if (errno != 0) |
| log_debug_errno(errno, "Failure to iterate NSS user database, ignoring: %m"); |
| |
| iterator->nss_iterating = false; |
| endpwent(); |
| } |
| |
| r = userdb_process(iterator, ret, NULL, NULL, NULL); |
| |
| if (r < 0) { |
| 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 (r < 0 && 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_STRING("root")), |
| JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(0)), |
| JSON_BUILD_PAIR("disposition", JSON_BUILD_STRING("intrinsic")))); |
| } |
| |
| static int synthetic_nobody_group_build(GroupRecord **ret) { |
| return group_record_build( |
| ret, |
| JSON_BUILD_OBJECT(JSON_BUILD_PAIR("groupName", JSON_BUILD_STRING(NOBODY_GROUP_NAME)), |
| JSON_BUILD_PAIR("gid", JSON_BUILD_UNSIGNED(GID_NOBODY)), |
| JSON_BUILD_PAIR("disposition", JSON_BUILD_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_compat(name)) |
| 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); |
| 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_AVOID_NSS) && !(iterator && iterator->nss_covered)) { |
| r = userdb_nss_compat_disable(); |
| if (r >= 0 || r == -EBUSY) { |
| iterator->nss_lock = r; |
| |
| r = nss_group_record_by_name(name, 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); |
| 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_AVOID_NSS) && !(iterator && iterator->nss_covered)) { |
| r = userdb_nss_compat_disable(); |
| if (r >= 0 || r == -EBUSY) { |
| iterator->nss_lock = r; |
| |
| r = nss_group_record_by_gid(gid, 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; |
| |
| assert(ret); |
| |
| iterator = userdb_iterator_new(LOOKUP_GROUP); |
| if (!iterator) |
| return -ENOMEM; |
| |
| iterator->synthesize_root = iterator->synthesize_nobody = !FLAGS_SET(flags, USERDB_DONT_SYNTHESIZE); |
| |
| r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetGroupRecord", true, NULL, flags); |
| |
| if (!FLAGS_SET(flags, USERDB_AVOID_NSS) && (r < 0 || !iterator->nss_covered)) { |
| iterator->nss_lock = userdb_nss_compat_disable(); |
| if (iterator->nss_lock < 0 && iterator->nss_lock != -EBUSY) |
| return iterator->nss_lock; |
| |
| setgrent(); |
| iterator->nss_iterating = true; |
| } if (r < 0) |
| return r; |
| |
| *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; |
| |
| 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); |
| } |
| |
| r = nss_group_to_group_record(gr, r >= 0 ? &sgrp : NULL, ret); |
| if (r < 0) |
| return r; |
| |
| if (ret) |
| (*ret)->incomplete = incomplete; |
| return r; |
| } |
| |
| if (errno != 0) |
| log_debug_errno(errno, "Failure to iterate NSS group database, ignoring: %m"); |
| |
| iterator->nss_iterating = false; |
| endgrent(); |
| } |
| |
| 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 (r < 0 && iterator->n_found > 0) |
| return -ESRCH; |
| |
| return r; |
| } |
| |
| 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; |
| |
| assert(ret); |
| |
| if (!valid_user_group_name_compat(name)) |
| 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); |
| if (!iterator) |
| return -ENOMEM; |
| |
| r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetMemberships", true, query, flags); |
| if ((r >= 0 && iterator->nss_covered) || FLAGS_SET(flags, USERDB_AVOID_NSS)) |
| goto finish; |
| |
| iterator->nss_lock = userdb_nss_compat_disable(); |
| if (iterator->nss_lock < 0 && iterator->nss_lock != -EBUSY) |
| return iterator->nss_lock; |
| |
| iterator->filter_user_name = strdup(name); |
| if (!iterator->filter_user_name) |
| return -ENOMEM; |
| |
| setgrent(); |
| iterator->nss_iterating = true; |
| |
| r = 0; |
| |
| finish: |
| if (r >= 0) |
| *ret = TAKE_PTR(iterator); |
| return r; |
| } |
| |
| 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; |
| _cleanup_(group_record_unrefp) GroupRecord *gr = NULL; |
| int r; |
| |
| assert(ret); |
| |
| if (!valid_user_group_name_compat(name)) |
| 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); |
| if (!iterator) |
| return -ENOMEM; |
| |
| r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetMemberships", true, query, flags); |
| if ((r >= 0 && iterator->nss_covered) || FLAGS_SET(flags, USERDB_AVOID_NSS)) |
| goto finish; |
| |
| iterator->nss_lock = userdb_nss_compat_disable(); |
| if (iterator->nss_lock < 0 && iterator->nss_lock != -EBUSY) |
| return iterator->nss_lock; |
| |
| /* 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, &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; |
| } |
| |
| r = 0; |
| |
| finish: |
| if (r >= 0) |
| *ret = TAKE_PTR(iterator); |
| |
| return r; |
| } |
| |
| int membershipdb_all(UserDBFlags flags, UserDBIterator **ret) { |
| _cleanup_(userdb_iterator_freep) UserDBIterator *iterator = NULL; |
| int r; |
| |
| assert(ret); |
| |
| iterator = userdb_iterator_new(LOOKUP_MEMBERSHIP); |
| if (!iterator) |
| return -ENOMEM; |
| |
| r = userdb_start_query(iterator, "io.systemd.UserDatabase.GetMemberships", true, NULL, flags); |
| if ((r >= 0 && iterator->nss_covered) || FLAGS_SET(flags, USERDB_AVOID_NSS)) |
| goto finish; |
| |
| iterator->nss_lock = userdb_nss_compat_disable(); |
| if (iterator->nss_lock < 0 && iterator->nss_lock != -EBUSY) |
| return iterator->nss_lock; |
| |
| setgrent(); |
| iterator->nss_iterating = true; |
| |
| r = 0; |
| |
| finish: |
| if (r >= 0) |
| *ret = TAKE_PTR(iterator); |
| |
| return r; |
| } |
| |
| int membershipdb_iterator_get( |
| UserDBIterator *iterator, |
| char **ret_user, |
| char **ret_group) { |
| |
| int r; |
| |
| assert(iterator); |
| |
| for (;;) { |
| /* If we are iteratring 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); |
| } |
| |
| 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; |
| } |
| |
| static int userdb_thread_sockaddr(struct sockaddr_un *ret_sa, socklen_t *ret_salen) { |
| static const uint8_t |
| k1[16] = { 0x35, 0xc1, 0x1f, 0x41, 0x59, 0xc6, 0xa0, 0xf9, 0x33, 0x4b, 0x17, 0x3d, 0xb9, 0xf6, 0x14, 0xd9 }, |
| k2[16] = { 0x6a, 0x11, 0x4c, 0x37, 0xe5, 0xa3, 0x8c, 0xa6, 0x93, 0x55, 0x64, 0x8c, 0x93, 0xee, 0xa1, 0x7b }; |
| |
| struct siphash sh; |
| uint64_t x, y; |
| pid_t tid; |
| void *p; |
| |
| assert(ret_sa); |
| assert(ret_salen); |
| |
| /* This calculates an AF_UNIX socket address in the abstract namespace whose existence works as an |
| * indicator whether to emulate NSS records for complex user records that are also available via the |
| * varlink protocol. The name of the socket is picked in a way so that: |
| * |
| * → it is per-thread (by hashing from the TID) |
| * |
| * → is not guessable for foreign processes (by hashing from the — hopefully secret — AT_RANDOM |
| * value every process gets passed from the kernel |
| * |
| * By using a socket the NSS emulation can be nicely turned off for limited amounts of time only, |
| * simply controlled by the lifetime of the fd itself. By using an AF_UNIX socket in the abstract |
| * namespace the lock is automatically cleaned up when the process dies abnormally. |
| * |
| */ |
| |
| p = ULONG_TO_PTR(getauxval(AT_RANDOM)); |
| if (!p) |
| return -EIO; |
| |
| tid = gettid(); |
| |
| siphash24_init(&sh, k1); |
| siphash24_compress(p, 16, &sh); |
| siphash24_compress(&tid, sizeof(tid), &sh); |
| x = siphash24_finalize(&sh); |
| |
| siphash24_init(&sh, k2); |
| siphash24_compress(p, 16, &sh); |
| siphash24_compress(&tid, sizeof(tid), &sh); |
| y = siphash24_finalize(&sh); |
| |
| *ret_sa = (struct sockaddr_un) { |
| .sun_family = AF_UNIX, |
| }; |
| |
| sprintf(ret_sa->sun_path + 1, "userdb-%016" PRIx64 "%016" PRIx64, x, y); |
| *ret_salen = offsetof(struct sockaddr_un, sun_path) + 1 + 7 + 32; |
| |
| return 0; |
| } |
| |
| int userdb_nss_compat_is_enabled(void) { |
| _cleanup_close_ int fd = -1; |
| union sockaddr_union sa; |
| socklen_t salen; |
| int r; |
| |
| /* Tests whether the NSS compatibility logic is currently turned on for the invoking thread. Returns |
| * true if NSS compatibility is turned on, i.e. whether NSS records shall be synthesized from complex |
| * user records. */ |
| |
| r = userdb_thread_sockaddr(&sa.un, &salen); |
| if (r < 0) |
| return r; |
| |
| fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0); |
| if (fd < 0) |
| return -errno; |
| |
| /* Try to connect(). This doesn't do anything really, except that it checks whether the socket |
| * address is bound at all. */ |
| if (connect(fd, &sa.sa, salen) < 0) { |
| if (errno == ECONNREFUSED) /* the socket is not bound, hence NSS emulation shall be done */ |
| return true; |
| |
| return -errno; |
| } |
| |
| return false; |
| } |
| |
| int userdb_nss_compat_disable(void) { |
| _cleanup_close_ int fd = -1; |
| union sockaddr_union sa; |
| socklen_t salen; |
| int r; |
| |
| /* Turn off the NSS compatibility logic for the invoking thread. By default NSS records are |
| * synthesized for all complex user records looked up via NSS. If this call is invoked this is |
| * disabled for the invoking thread, but only for it. A caller that natively supports the varlink |
| * user record protocol may use that to turn off the compatibility for NSS lookups. */ |
| |
| r = userdb_thread_sockaddr(&sa.un, &salen); |
| if (r < 0) |
| return r; |
| |
| fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0); |
| if (fd < 0) |
| return -errno; |
| |
| if (bind(fd, &sa.sa, salen) < 0) { |
| if (errno == EADDRINUSE) /* lock already taken, convert this into a recognizable error */ |
| return -EBUSY; |
| |
| return -errno; |
| } |
| |
| return TAKE_FD(fd); |
| } |