| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <endian.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <pwd.h> |
| #include <security/_pam_macros.h> |
| #include <security/pam_ext.h> |
| #include <security/pam_misc.h> |
| #include <security/pam_modules.h> |
| #include <security/pam_modutil.h> |
| #include <sys/file.h> |
| #include <sys/stat.h> |
| #include <sys/sysmacros.h> |
| #include <sys/types.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "audit-util.h" |
| #include "bus-common-errors.h" |
| #include "bus-error.h" |
| #include "bus-internal.h" |
| #include "bus-locator.h" |
| #include "cgroup-setup.h" |
| #include "errno-util.h" |
| #include "fd-util.h" |
| #include "fileio.h" |
| #include "format-util.h" |
| #include "fs-util.h" |
| #include "hostname-util.h" |
| #include "locale-util.h" |
| #include "login-util.h" |
| #include "macro.h" |
| #include "pam-util.h" |
| #include "parse-util.h" |
| #include "path-util.h" |
| #include "percent-util.h" |
| #include "process-util.h" |
| #include "rlimit-util.h" |
| #include "socket-util.h" |
| #include "stdio-util.h" |
| #include "strv.h" |
| #include "terminal-util.h" |
| #include "user-util.h" |
| #include "userdb.h" |
| |
| #define LOGIN_SLOW_BUS_CALL_TIMEOUT_USEC (2*USEC_PER_MINUTE) |
| |
| static int parse_argv( |
| pam_handle_t *handle, |
| int argc, const char **argv, |
| const char **class, |
| const char **type, |
| const char **desktop, |
| bool *debug) { |
| |
| unsigned i; |
| |
| assert(argc >= 0); |
| assert(argc == 0 || argv); |
| |
| for (i = 0; i < (unsigned) argc; i++) { |
| const char *p; |
| |
| if ((p = startswith(argv[i], "class="))) { |
| if (class) |
| *class = p; |
| |
| } else if ((p = startswith(argv[i], "type="))) { |
| if (type) |
| *type = p; |
| |
| } else if ((p = startswith(argv[i], "desktop="))) { |
| if (desktop) |
| *desktop = p; |
| |
| } else if (streq(argv[i], "debug")) { |
| if (debug) |
| *debug = true; |
| |
| } else if ((p = startswith(argv[i], "debug="))) { |
| int k; |
| |
| k = parse_boolean(p); |
| if (k < 0) |
| pam_syslog(handle, LOG_WARNING, "Failed to parse debug= argument, ignoring: %s", p); |
| else if (debug) |
| *debug = k; |
| |
| } else |
| pam_syslog(handle, LOG_WARNING, "Unknown parameter '%s', ignoring", argv[i]); |
| } |
| |
| return 0; |
| } |
| |
| static int acquire_user_record( |
| pam_handle_t *handle, |
| UserRecord **ret_record) { |
| |
| _cleanup_(user_record_unrefp) UserRecord *ur = NULL; |
| const char *username = NULL, *json = NULL; |
| _cleanup_free_ char *field = NULL; |
| int r; |
| |
| assert(handle); |
| |
| r = pam_get_user(handle, &username, NULL); |
| if (r != PAM_SUCCESS) { |
| pam_syslog(handle, LOG_ERR, "Failed to get user name: %s", pam_strerror(handle, r)); |
| return r; |
| } |
| |
| if (isempty(username)) { |
| pam_syslog(handle, LOG_ERR, "User name not valid."); |
| return PAM_SERVICE_ERR; |
| } |
| |
| /* If pam_systemd_homed (or some other module) already acquired the user record we can reuse it |
| * here. */ |
| field = strjoin("systemd-user-record-", username); |
| if (!field) |
| return pam_log_oom(handle); |
| |
| r = pam_get_data(handle, field, (const void**) &json); |
| if (!IN_SET(r, PAM_SUCCESS, PAM_NO_MODULE_DATA)) { |
| pam_syslog(handle, LOG_ERR, "Failed to get PAM user record data: %s", pam_strerror(handle, r)); |
| return r; |
| } |
| if (r == PAM_SUCCESS && json) { |
| _cleanup_(json_variant_unrefp) JsonVariant *v = NULL; |
| |
| /* Parse cached record */ |
| r = json_parse(json, JSON_PARSE_SENSITIVE, &v, NULL, NULL); |
| if (r < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to parse JSON user record: %s", strerror_safe(r)); |
| return PAM_SERVICE_ERR; |
| } |
| |
| ur = user_record_new(); |
| if (!ur) |
| return pam_log_oom(handle); |
| |
| r = user_record_load(ur, v, USER_RECORD_LOAD_REFUSE_SECRET|USER_RECORD_PERMISSIVE); |
| if (r < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to load user record: %s", strerror_safe(r)); |
| return PAM_SERVICE_ERR; |
| } |
| |
| /* Safety check if cached record actually matches what we are looking for */ |
| if (!streq_ptr(username, ur->user_name)) { |
| pam_syslog(handle, LOG_ERR, "Acquired user record does not match user name."); |
| return PAM_SERVICE_ERR; |
| } |
| } else { |
| _cleanup_free_ char *formatted = NULL; |
| |
| /* Request the record ourselves */ |
| r = userdb_by_name(username, 0, &ur); |
| if (r < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to get user record: %s", strerror_safe(r)); |
| return PAM_USER_UNKNOWN; |
| } |
| |
| r = json_variant_format(ur->json, 0, &formatted); |
| if (r < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to format user JSON: %s", strerror_safe(r)); |
| return PAM_SERVICE_ERR; |
| } |
| |
| /* And cache it for everyone else */ |
| r = pam_set_data(handle, field, formatted, pam_cleanup_free); |
| if (r < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to set PAM user record data '%s': %s", |
| field, pam_strerror(handle, r)); |
| return r; |
| } |
| |
| TAKE_PTR(formatted); |
| } |
| |
| if (!uid_is_valid(ur->uid)) { |
| pam_syslog(handle, LOG_ERR, "Acquired user record does not have a UID."); |
| return PAM_SERVICE_ERR; |
| } |
| |
| if (ret_record) |
| *ret_record = TAKE_PTR(ur); |
| |
| return PAM_SUCCESS; |
| } |
| |
| static bool display_is_local(const char *display) { |
| assert(display); |
| |
| return |
| display[0] == ':' && |
| display[1] >= '0' && |
| display[1] <= '9'; |
| } |
| |
| static int socket_from_display(const char *display, char **path) { |
| size_t k; |
| char *f, *c; |
| |
| assert(display); |
| assert(path); |
| |
| if (!display_is_local(display)) |
| return -EINVAL; |
| |
| k = strspn(display+1, "0123456789"); |
| |
| f = new(char, STRLEN("/tmp/.X11-unix/X") + k + 1); |
| if (!f) |
| return -ENOMEM; |
| |
| c = stpcpy(f, "/tmp/.X11-unix/X"); |
| memcpy(c, display+1, k); |
| c[k] = 0; |
| |
| *path = f; |
| |
| return 0; |
| } |
| |
| static int get_seat_from_display(const char *display, const char **seat, uint32_t *vtnr) { |
| union sockaddr_union sa; |
| socklen_t sa_len; |
| _cleanup_free_ char *p = NULL, *sys_path = NULL, *tty = NULL; |
| _cleanup_close_ int fd = -1; |
| struct ucred ucred; |
| int v, r; |
| dev_t display_ctty; |
| |
| assert(display); |
| assert(vtnr); |
| |
| /* We deduce the X11 socket from the display name, then use |
| * SO_PEERCRED to determine the X11 server process, ask for |
| * the controlling tty of that and if it's a VC then we know |
| * the seat and the virtual terminal. Sounds ugly, is only |
| * semi-ugly. */ |
| |
| r = socket_from_display(display, &p); |
| if (r < 0) |
| return r; |
| r = sockaddr_un_set_path(&sa.un, p); |
| if (r < 0) |
| return r; |
| sa_len = r; |
| |
| fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0); |
| if (fd < 0) |
| return -errno; |
| |
| if (connect(fd, &sa.sa, sa_len) < 0) |
| return -errno; |
| |
| r = getpeercred(fd, &ucred); |
| if (r < 0) |
| return r; |
| |
| r = get_ctty_devnr(ucred.pid, &display_ctty); |
| if (r < 0) |
| return r; |
| |
| if (asprintf(&sys_path, "/sys/dev/char/%d:%d", major(display_ctty), minor(display_ctty)) < 0) |
| return -ENOMEM; |
| r = readlink_value(sys_path, &tty); |
| if (r < 0) |
| return r; |
| |
| v = vtnr_from_tty(tty); |
| if (v < 0) |
| return v; |
| else if (v == 0) |
| return -ENOENT; |
| |
| if (seat) |
| *seat = "seat0"; |
| *vtnr = (uint32_t) v; |
| |
| return 0; |
| } |
| |
| static int export_legacy_dbus_address( |
| pam_handle_t *handle, |
| const char *runtime) { |
| |
| const char *s; |
| _cleanup_free_ char *t = NULL; |
| int r = PAM_BUF_ERR; |
| |
| /* We need to export $DBUS_SESSION_BUS_ADDRESS because various applications will not connect |
| * correctly to the bus without it. This setting matches what dbus.socket does for the user |
| * session using 'systemctl --user set-environment'. We want to have the same configuration |
| * in processes started from the PAM session. |
| * |
| * The setting of the address is guarded by the access() check because it is also possible to compile |
| * dbus without --enable-user-session, in which case this socket is not used, and |
| * $DBUS_SESSION_BUS_ADDRESS should not be set. An alternative approach would to not do the access() |
| * check here, and let applications try on their own, by using "unix:path=%s/bus;autolaunch:". But we |
| * expect the socket to be present by the time we do this check, so we can just as well check once |
| * here. */ |
| |
| s = strjoina(runtime, "/bus"); |
| if (access(s, F_OK) < 0) |
| return PAM_SUCCESS; |
| |
| if (asprintf(&t, DEFAULT_USER_BUS_ADDRESS_FMT, runtime) < 0) |
| return pam_log_oom(handle); |
| |
| r = pam_misc_setenv(handle, "DBUS_SESSION_BUS_ADDRESS", t, 0); |
| if (r != PAM_SUCCESS) { |
| pam_syslog(handle, LOG_ERR, "Failed to set bus variable: %s", pam_strerror(handle, r)); |
| return r; |
| } |
| |
| return PAM_SUCCESS; |
| } |
| |
| static int append_session_memory_max(pam_handle_t *handle, sd_bus_message *m, const char *limit) { |
| uint64_t val; |
| int r; |
| |
| if (isempty(limit)) |
| return PAM_SUCCESS; |
| |
| if (streq(limit, "infinity")) { |
| r = sd_bus_message_append(m, "(sv)", "MemoryMax", "t", UINT64_MAX); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| return PAM_SUCCESS; |
| } |
| |
| r = parse_permyriad(limit); |
| if (r >= 0) { |
| r = sd_bus_message_append(m, "(sv)", "MemoryMaxScale", "u", UINT32_SCALE_FROM_PERMYRIAD(r)); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| return PAM_SUCCESS; |
| } |
| |
| r = parse_size(limit, 1024, &val); |
| if (r >= 0) { |
| r = sd_bus_message_append(m, "(sv)", "MemoryMax", "t", val); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| return PAM_SUCCESS; |
| } |
| |
| pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.memory_max, ignoring: %s", limit); |
| return PAM_SUCCESS; |
| } |
| |
| static int append_session_runtime_max_sec(pam_handle_t *handle, sd_bus_message *m, const char *limit) { |
| usec_t val; |
| int r; |
| |
| /* No need to parse "infinity" here, it will be set by default later in scope_init() */ |
| if (isempty(limit) || streq(limit, "infinity")) |
| return PAM_SUCCESS; |
| |
| r = parse_sec(limit, &val); |
| if (r >= 0) { |
| r = sd_bus_message_append(m, "(sv)", "RuntimeMaxUSec", "t", (uint64_t) val); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| } else |
| pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.runtime_max_sec: %s, ignoring.", limit); |
| |
| return PAM_SUCCESS; |
| } |
| |
| static int append_session_tasks_max(pam_handle_t *handle, sd_bus_message *m, const char *limit) { |
| uint64_t val; |
| int r; |
| |
| /* No need to parse "infinity" here, it will be set unconditionally later in manager_start_scope() */ |
| if (isempty(limit) || streq(limit, "infinity")) |
| return PAM_SUCCESS; |
| |
| r = safe_atou64(limit, &val); |
| if (r >= 0) { |
| r = sd_bus_message_append(m, "(sv)", "TasksMax", "t", val); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| } else |
| pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.tasks_max, ignoring: %s", limit); |
| |
| return PAM_SUCCESS; |
| } |
| |
| static int append_session_cg_weight(pam_handle_t *handle, sd_bus_message *m, const char *limit, const char *field) { |
| uint64_t val; |
| int r; |
| |
| if (isempty(limit)) |
| return PAM_SUCCESS; |
| |
| r = cg_weight_parse(limit, &val); |
| if (r >= 0) { |
| r = sd_bus_message_append(m, "(sv)", field, "t", val); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| } else if (streq(field, "CPUWeight")) |
| pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.cpu_weight, ignoring: %s", limit); |
| else |
| pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.io_weight, ignoring: %s", limit); |
| |
| return PAM_SUCCESS; |
| } |
| |
| static const char* getenv_harder(pam_handle_t *handle, const char *key, const char *fallback) { |
| const char *v; |
| |
| assert(handle); |
| assert(key); |
| |
| /* Looks for an environment variable, preferably in the environment block associated with the |
| * specified PAM handle, falling back to the process' block instead. Why check both? Because we want |
| * to permit configuration of session properties from unit files that invoke PAM services, so that |
| * PAM services don't have to be reworked to set systemd-specific properties, but these properties |
| * can still be set from the unit file Environment= block. */ |
| |
| v = pam_getenv(handle, key); |
| if (!isempty(v)) |
| return v; |
| |
| /* We use secure_getenv() here, since we might get loaded into su/sudo, which are SUID. Ideally |
| * they'd clean up the environment before invoking foreign code (such as PAM modules), but alas they |
| * currently don't (to be precise, they clean up the environment they pass to their children, but |
| * not their own environ[]). */ |
| v = secure_getenv(key); |
| if (!isempty(v)) |
| return v; |
| |
| return fallback; |
| } |
| |
| static int update_environment(pam_handle_t *handle, const char *key, const char *value) { |
| int r; |
| |
| assert(handle); |
| assert(key); |
| |
| /* Updates the environment, but only if there's actually a value set. Also, log about errors */ |
| |
| if (isempty(value)) |
| return PAM_SUCCESS; |
| |
| r = pam_misc_setenv(handle, key, value, 0); |
| if (r != PAM_SUCCESS) |
| pam_syslog(handle, LOG_ERR, "Failed to set environment variable %s: %s", key, pam_strerror(handle, r)); |
| |
| return r; |
| } |
| |
| static bool validate_runtime_directory(pam_handle_t *handle, const char *path, uid_t uid) { |
| struct stat st; |
| |
| assert(handle); |
| assert(path); |
| |
| /* Some extra paranoia: let's not set $XDG_RUNTIME_DIR if the directory we'd set it to isn't actually |
| * set up properly for us. This is supposed to provide a careful safety net for supporting su/sudo |
| * type transitions: in that case the UID changes, but the session and thus the user owning it |
| * doesn't change. Since the $XDG_RUNTIME_DIR lifecycle is bound to the session's user being logged |
| * in at least once we should be particularly careful when setting the environment variable, since |
| * otherwise we might end up setting $XDG_RUNTIME_DIR to some directory owned by the wrong user. */ |
| |
| if (!path_is_absolute(path)) { |
| pam_syslog(handle, LOG_ERR, "Provided runtime directory '%s' is not absolute.", path); |
| goto fail; |
| } |
| |
| if (lstat(path, &st) < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to stat() runtime directory '%s': %s", path, strerror_safe(errno)); |
| goto fail; |
| } |
| |
| if (!S_ISDIR(st.st_mode)) { |
| pam_syslog(handle, LOG_ERR, "Runtime directory '%s' is not actually a directory.", path); |
| goto fail; |
| } |
| |
| if (st.st_uid != uid) { |
| pam_syslog(handle, LOG_ERR, "Runtime directory '%s' is not owned by UID " UID_FMT ", as it should.", path, uid); |
| goto fail; |
| } |
| |
| return true; |
| |
| fail: |
| pam_syslog(handle, LOG_WARNING, "Not setting $XDG_RUNTIME_DIR, as the directory is not in order."); |
| return false; |
| } |
| |
| static int pam_putenv_and_log(pam_handle_t *handle, const char *e, bool debug) { |
| int r; |
| |
| assert(handle); |
| assert(e); |
| |
| r = pam_putenv(handle, e); |
| if (r != PAM_SUCCESS) { |
| pam_syslog(handle, LOG_ERR, "Failed to set PAM environment variable %s: %s", e, pam_strerror(handle, r)); |
| return r; |
| } |
| |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "PAM environment variable %s set based on user record.", e); |
| |
| return PAM_SUCCESS; |
| } |
| |
| static int apply_user_record_settings(pam_handle_t *handle, UserRecord *ur, bool debug) { |
| char **i; |
| int r; |
| |
| assert(handle); |
| assert(ur); |
| |
| if (ur->umask != MODE_INVALID) { |
| umask(ur->umask); |
| |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Set user umask to %04o based on user record.", ur->umask); |
| } |
| |
| STRV_FOREACH(i, ur->environment) { |
| _cleanup_free_ char *n = NULL; |
| const char *e; |
| |
| assert_se(e = strchr(*i, '=')); /* environment was already validated while parsing JSON record, this thus must hold */ |
| |
| n = strndup(*i, e - *i); |
| if (!n) |
| return pam_log_oom(handle); |
| |
| if (pam_getenv(handle, n)) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "PAM environment variable $%s already set, not changing based on record.", *i); |
| continue; |
| } |
| |
| r = pam_putenv_and_log(handle, *i, debug); |
| if (r != PAM_SUCCESS) |
| return r; |
| } |
| |
| if (ur->email_address) { |
| if (pam_getenv(handle, "EMAIL")) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "PAM environment variable $EMAIL already set, not changing based on user record."); |
| } else { |
| _cleanup_free_ char *joined = NULL; |
| |
| joined = strjoin("EMAIL=", ur->email_address); |
| if (!joined) |
| return pam_log_oom(handle); |
| |
| r = pam_putenv_and_log(handle, joined, debug); |
| if (r != PAM_SUCCESS) |
| return r; |
| } |
| } |
| |
| if (ur->time_zone) { |
| if (pam_getenv(handle, "TZ")) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "PAM environment variable $TZ already set, not changing based on user record."); |
| } else if (!timezone_is_valid(ur->time_zone, LOG_DEBUG)) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Time zone specified in user record is not valid locally, not setting $TZ."); |
| } else { |
| _cleanup_free_ char *joined = NULL; |
| |
| joined = strjoin("TZ=:", ur->time_zone); |
| if (!joined) |
| return pam_log_oom(handle); |
| |
| r = pam_putenv_and_log(handle, joined, debug); |
| if (r != PAM_SUCCESS) |
| return r; |
| } |
| } |
| |
| if (ur->preferred_language) { |
| if (pam_getenv(handle, "LANG")) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "PAM environment variable $LANG already set, not changing based on user record."); |
| } else if (locale_is_installed(ur->preferred_language) <= 0) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Preferred language specified in user record is not valid or not installed, not setting $LANG."); |
| } else { |
| _cleanup_free_ char *joined = NULL; |
| |
| joined = strjoin("LANG=", ur->preferred_language); |
| if (!joined) |
| return pam_log_oom(handle); |
| |
| r = pam_putenv_and_log(handle, joined, debug); |
| if (r != PAM_SUCCESS) |
| return r; |
| } |
| } |
| |
| if (nice_is_valid(ur->nice_level)) { |
| if (nice(ur->nice_level) < 0) |
| pam_syslog(handle, LOG_ERR, "Failed to set nice level to %i, ignoring: %s", ur->nice_level, strerror_safe(errno)); |
| else if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Nice level set, based on user record."); |
| } |
| |
| for (int rl = 0; rl < _RLIMIT_MAX; rl++) { |
| |
| if (!ur->rlimits[rl]) |
| continue; |
| |
| r = setrlimit_closest(rl, ur->rlimits[rl]); |
| if (r < 0) |
| pam_syslog(handle, LOG_ERR, "Failed to set resource limit %s, ignoring: %s", rlimit_to_string(rl), strerror_safe(r)); |
| else if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Resource limit %s set, based on user record.", rlimit_to_string(rl)); |
| } |
| |
| return PAM_SUCCESS; |
| } |
| |
| static int configure_runtime_directory( |
| pam_handle_t *handle, |
| UserRecord *ur, |
| const char *rt) { |
| |
| int r; |
| |
| assert(handle); |
| assert(ur); |
| assert(rt); |
| |
| if (!validate_runtime_directory(handle, rt, ur->uid)) |
| return PAM_SUCCESS; |
| |
| r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", rt, 0); |
| if (r != PAM_SUCCESS) { |
| pam_syslog(handle, LOG_ERR, "Failed to set runtime dir: %s", pam_strerror(handle, r)); |
| return r; |
| } |
| |
| return export_legacy_dbus_address(handle, rt); |
| } |
| |
| _public_ PAM_EXTERN int pam_sm_open_session( |
| pam_handle_t *handle, |
| int flags, |
| int argc, const char **argv) { |
| |
| _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; |
| _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *reply = NULL; |
| const char |
| *id, *object_path, *runtime_path, |
| *service = NULL, |
| *tty = NULL, *display = NULL, |
| *remote_user = NULL, *remote_host = NULL, |
| *seat = NULL, |
| *type = NULL, *class = NULL, |
| *class_pam = NULL, *type_pam = NULL, *cvtnr = NULL, *desktop = NULL, *desktop_pam = NULL, |
| *memory_max = NULL, *tasks_max = NULL, *cpu_weight = NULL, *io_weight = NULL, *runtime_max_sec = NULL; |
| _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; |
| _cleanup_(user_record_unrefp) UserRecord *ur = NULL; |
| int session_fd = -1, existing, r; |
| bool debug = false, remote; |
| uint32_t vtnr = 0; |
| uid_t original_uid; |
| |
| assert(handle); |
| |
| if (parse_argv(handle, |
| argc, argv, |
| &class_pam, |
| &type_pam, |
| &desktop_pam, |
| &debug) < 0) |
| return PAM_SESSION_ERR; |
| |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "pam-systemd initializing"); |
| |
| r = acquire_user_record(handle, &ur); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| /* Make most of this a NOP on non-logind systems */ |
| if (!logind_running()) |
| goto success; |
| |
| /* Make sure we don't enter a loop by talking to |
| * systemd-logind when it is actually waiting for the |
| * background to finish start-up. If the service is |
| * "systemd-user" we simply set XDG_RUNTIME_DIR and |
| * leave. */ |
| |
| (void) pam_get_item(handle, PAM_SERVICE, (const void**) &service); |
| if (streq_ptr(service, "systemd-user")) { |
| char rt[STRLEN("/run/user/") + DECIMAL_STR_MAX(uid_t)]; |
| |
| xsprintf(rt, "/run/user/"UID_FMT, ur->uid); |
| r = configure_runtime_directory(handle, ur, rt); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| goto success; |
| } |
| |
| /* Otherwise, we ask logind to create a session for us */ |
| |
| (void) pam_get_item(handle, PAM_XDISPLAY, (const void**) &display); |
| (void) pam_get_item(handle, PAM_TTY, (const void**) &tty); |
| (void) pam_get_item(handle, PAM_RUSER, (const void**) &remote_user); |
| (void) pam_get_item(handle, PAM_RHOST, (const void**) &remote_host); |
| |
| seat = getenv_harder(handle, "XDG_SEAT", NULL); |
| cvtnr = getenv_harder(handle, "XDG_VTNR", NULL); |
| type = getenv_harder(handle, "XDG_SESSION_TYPE", type_pam); |
| class = getenv_harder(handle, "XDG_SESSION_CLASS", class_pam); |
| desktop = getenv_harder(handle, "XDG_SESSION_DESKTOP", desktop_pam); |
| |
| tty = strempty(tty); |
| |
| if (strchr(tty, ':')) { |
| /* A tty with a colon is usually an X11 display, placed there to show up in utmp. We rearrange things |
| * and don't pretend that an X display was a tty. */ |
| if (isempty(display)) |
| display = tty; |
| tty = NULL; |
| |
| } else if (streq(tty, "cron")) { |
| /* cron is setting PAM_TTY to "cron" for some reason (the commit carries no information why, but |
| * probably because it wants to set it to something as pam_time/pam_access/… require PAM_TTY to be set |
| * (as they otherwise even try to update it!) — but cron doesn't actually allocate a TTY for its forked |
| * off processes.) */ |
| type = "unspecified"; |
| class = "background"; |
| tty = NULL; |
| |
| } else if (streq(tty, "ssh")) { |
| /* ssh has been setting PAM_TTY to "ssh" (for the same reason as cron does this, see above. For further |
| * details look for "PAM_TTY_KLUDGE" in the openssh sources). */ |
| type ="tty"; |
| class = "user"; |
| tty = NULL; /* This one is particularly sad, as this means that ssh sessions — even though usually |
| * associated with a pty — won't be tracked by their tty in logind. This is because ssh |
| * does the PAM session registration early for new connections, and registers a pty only |
| * much later (this is because it doesn't know yet if it needs one at all, as whether to |
| * register a pty or not is negotiated much later in the protocol). */ |
| |
| } else |
| /* Chop off leading /dev prefix that some clients specify, but others do not. */ |
| tty = skip_dev_prefix(tty); |
| |
| /* If this fails vtnr will be 0, that's intended */ |
| if (!isempty(cvtnr)) |
| (void) safe_atou32(cvtnr, &vtnr); |
| |
| if (!isempty(display) && !vtnr) { |
| if (isempty(seat)) |
| (void) get_seat_from_display(display, &seat, &vtnr); |
| else if (streq(seat, "seat0")) |
| (void) get_seat_from_display(display, NULL, &vtnr); |
| } |
| |
| if (seat && !streq(seat, "seat0") && vtnr != 0) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Ignoring vtnr %"PRIu32" for %s which is not seat0", vtnr, seat); |
| vtnr = 0; |
| } |
| |
| if (isempty(type)) |
| type = !isempty(display) ? "x11" : |
| !isempty(tty) ? "tty" : "unspecified"; |
| |
| if (isempty(class)) |
| class = streq(type, "unspecified") ? "background" : "user"; |
| |
| remote = !isempty(remote_host) && !is_localhost(remote_host); |
| |
| (void) pam_get_data(handle, "systemd.memory_max", (const void **)&memory_max); |
| (void) pam_get_data(handle, "systemd.tasks_max", (const void **)&tasks_max); |
| (void) pam_get_data(handle, "systemd.cpu_weight", (const void **)&cpu_weight); |
| (void) pam_get_data(handle, "systemd.io_weight", (const void **)&io_weight); |
| (void) pam_get_data(handle, "systemd.runtime_max_sec", (const void **)&runtime_max_sec); |
| |
| /* Talk to logind over the message bus */ |
| |
| r = pam_acquire_bus_connection(handle, &bus); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| if (debug) { |
| pam_syslog(handle, LOG_DEBUG, "Asking logind to create session: " |
| "uid="UID_FMT" pid="PID_FMT" service=%s type=%s class=%s desktop=%s seat=%s vtnr=%"PRIu32" tty=%s display=%s remote=%s remote_user=%s remote_host=%s", |
| ur->uid, getpid_cached(), |
| strempty(service), |
| type, class, strempty(desktop), |
| strempty(seat), vtnr, strempty(tty), strempty(display), |
| yes_no(remote), strempty(remote_user), strempty(remote_host)); |
| pam_syslog(handle, LOG_DEBUG, "Session limits: " |
| "memory_max=%s tasks_max=%s cpu_weight=%s io_weight=%s runtime_max_sec=%s", |
| strna(memory_max), strna(tasks_max), strna(cpu_weight), strna(io_weight), strna(runtime_max_sec)); |
| } |
| |
| r = bus_message_new_method_call(bus, &m, bus_login_mgr, "CreateSession"); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| r = sd_bus_message_append(m, "uusssssussbss", |
| (uint32_t) ur->uid, |
| 0, |
| service, |
| type, |
| class, |
| desktop, |
| seat, |
| vtnr, |
| tty, |
| display, |
| remote, |
| remote_user, |
| remote_host); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| r = sd_bus_message_open_container(m, 'a', "(sv)"); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| r = append_session_memory_max(handle, m, memory_max); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = append_session_runtime_max_sec(handle, m, runtime_max_sec); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = append_session_tasks_max(handle, m, tasks_max); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = append_session_cg_weight(handle, m, cpu_weight, "CPUWeight"); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = append_session_cg_weight(handle, m, io_weight, "IOWeight"); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = sd_bus_message_close_container(m); |
| if (r < 0) |
| return pam_bus_log_create_error(handle, r); |
| |
| r = sd_bus_call(bus, m, LOGIN_SLOW_BUS_CALL_TIMEOUT_USEC, &error, &reply); |
| if (r < 0) { |
| if (sd_bus_error_has_name(&error, BUS_ERROR_SESSION_BUSY)) { |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Not creating session: %s", bus_error_message(&error, r)); |
| |
| /* We are already in a session, don't do anything */ |
| goto success; |
| } else { |
| pam_syslog(handle, LOG_ERR, "Failed to create session: %s", bus_error_message(&error, r)); |
| return PAM_SESSION_ERR; |
| } |
| } |
| |
| r = sd_bus_message_read(reply, |
| "soshusub", |
| &id, |
| &object_path, |
| &runtime_path, |
| &session_fd, |
| &original_uid, |
| &seat, |
| &vtnr, |
| &existing); |
| if (r < 0) |
| return pam_bus_log_parse_error(handle, r); |
| |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "Reply from logind: " |
| "id=%s object_path=%s runtime_path=%s session_fd=%d seat=%s vtnr=%u original_uid=%u", |
| id, object_path, runtime_path, session_fd, seat, vtnr, original_uid); |
| |
| r = update_environment(handle, "XDG_SESSION_ID", id); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| if (original_uid == ur->uid) { |
| /* Don't set $XDG_RUNTIME_DIR if the user we now authenticated for does not match the |
| * original user of the session. We do this in order not to result in privileged apps |
| * clobbering the runtime directory unnecessarily. */ |
| |
| r = configure_runtime_directory(handle, ur, runtime_path); |
| if (r != PAM_SUCCESS) |
| return r; |
| } |
| |
| /* Most likely we got the session/type/class from environment variables, but might have gotten the data |
| * somewhere else (for example PAM module parameters). Let's now update the environment variables, so that this |
| * data is inherited into the session processes, and programs can rely on them to be initialized. */ |
| |
| r = update_environment(handle, "XDG_SESSION_TYPE", type); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = update_environment(handle, "XDG_SESSION_CLASS", class); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = update_environment(handle, "XDG_SESSION_DESKTOP", desktop); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = update_environment(handle, "XDG_SEAT", seat); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| if (vtnr > 0) { |
| char buf[DECIMAL_STR_MAX(vtnr)]; |
| sprintf(buf, "%u", vtnr); |
| |
| r = update_environment(handle, "XDG_VTNR", buf); |
| if (r != PAM_SUCCESS) |
| return r; |
| } |
| |
| r = pam_set_data(handle, "systemd.existing", INT_TO_PTR(!!existing), NULL); |
| if (r != PAM_SUCCESS) { |
| pam_syslog(handle, LOG_ERR, "Failed to install existing flag: %s", pam_strerror(handle, r)); |
| return r; |
| } |
| |
| if (session_fd >= 0) { |
| session_fd = fcntl(session_fd, F_DUPFD_CLOEXEC, 3); |
| if (session_fd < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to dup session fd: %m"); |
| return PAM_SESSION_ERR; |
| } |
| |
| r = pam_set_data(handle, "systemd.session-fd", FD_TO_PTR(session_fd), NULL); |
| if (r != PAM_SUCCESS) { |
| pam_syslog(handle, LOG_ERR, "Failed to install session fd: %s", pam_strerror(handle, r)); |
| safe_close(session_fd); |
| return r; |
| } |
| } |
| |
| success: |
| r = apply_user_record_settings(handle, ur, debug); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| /* Let's release the D-Bus connection, after all the session might live quite a long time, and we are |
| * not going to use the bus connection in that time, so let's better close before the daemon kicks us |
| * off because we are not processing anything. */ |
| (void) pam_release_bus_connection(handle); |
| return PAM_SUCCESS; |
| } |
| |
| _public_ PAM_EXTERN int pam_sm_close_session( |
| pam_handle_t *handle, |
| int flags, |
| int argc, const char **argv) { |
| |
| const void *existing = NULL; |
| bool debug = false; |
| const char *id; |
| int r; |
| |
| assert(handle); |
| |
| if (parse_argv(handle, |
| argc, argv, |
| NULL, |
| NULL, |
| NULL, |
| &debug) < 0) |
| return PAM_SESSION_ERR; |
| |
| if (debug) |
| pam_syslog(handle, LOG_DEBUG, "pam-systemd shutting down"); |
| |
| /* Only release session if it wasn't pre-existing when we |
| * tried to create it */ |
| (void) pam_get_data(handle, "systemd.existing", &existing); |
| |
| id = pam_getenv(handle, "XDG_SESSION_ID"); |
| if (id && !existing) { |
| _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL; |
| _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL; |
| |
| /* Before we go and close the FIFO we need to tell logind that this is a clean session |
| * shutdown, so that it doesn't just go and slaughter us immediately after closing the fd */ |
| |
| r = pam_acquire_bus_connection(handle, &bus); |
| if (r != PAM_SUCCESS) |
| return r; |
| |
| r = bus_call_method(bus, bus_login_mgr, "ReleaseSession", &error, NULL, "s", id); |
| if (r < 0) { |
| pam_syslog(handle, LOG_ERR, "Failed to release session: %s", bus_error_message(&error, r)); |
| return PAM_SESSION_ERR; |
| } |
| } |
| |
| /* Note that we are knowingly leaking the FIFO fd here. This way, logind can watch us die. If we |
| * closed it here it would not have any clue when that is completed. Given that one cannot really |
| * have multiple PAM sessions open from the same process this means we will leak one FD at max. */ |
| |
| return PAM_SUCCESS; |
| } |
