#include <sys/file.h>
#include <pwd.h>
#include <endian.h>
+#include <sys/capability.h>
#include <security/pam_modules.h>
#include <security/_pam_macros.h>
bool *create_session,
bool *kill_session,
bool *kill_user,
- bool *keep_root,
- char ***controllers) {
+ char ***controllers,
+ char ***reset_controllers,
+ char ***kill_only_users,
+ char ***kill_exclude_users) {
unsigned i;
- bool controller_set = false;
+ bool reset_controller_set = false;
+ bool kill_exclude_users_set = false;
assert(argc >= 0);
assert(argc == 0 || argv);
if (kill_user)
*kill_user = k;
- } else if (startswith(argv[i], "keep-root=")) {
- if ((k = parse_boolean(argv[i] + 10)) < 0) {
- pam_syslog(handle, LOG_ERR, "Failed to parse keep-root= argument.");
- return k;
- }
-
- if (keep_root)
- *keep_root = k;
-
} else if (startswith(argv[i], "controllers=")) {
if (controllers) {
*controllers = l;
}
- controller_set = true;
+ } else if (startswith(argv[i], "reset-controllers=")) {
+
+ if (reset_controllers) {
+ char **l;
+
+ if (!(l = strv_split(argv[i] + 18, ","))) {
+ pam_syslog(handle, LOG_ERR, "Out of memory.");
+ return -ENOMEM;
+ }
+
+ strv_free(*reset_controllers);
+ *reset_controllers = l;
+ }
+
+ reset_controller_set = true;
+
+ } else if (startswith(argv[i], "kill-only-users=")) {
+
+ if (kill_only_users) {
+ char **l;
+
+ if (!(l = strv_split(argv[i] + 16, ","))) {
+ pam_syslog(handle, LOG_ERR, "Out of memory.");
+ return -ENOMEM;
+ }
+
+ strv_free(*kill_only_users);
+ *kill_only_users = l;
+ }
+
+ } else if (startswith(argv[i], "kill-exclude-users=")) {
+
+ if (kill_exclude_users) {
+ char **l;
+
+ if (!(l = strv_split(argv[i] + 19, ","))) {
+ pam_syslog(handle, LOG_ERR, "Out of memory.");
+ return -ENOMEM;
+ }
+
+ strv_free(*kill_exclude_users);
+ *kill_exclude_users = l;
+ }
+
+ kill_exclude_users_set = true;
} else {
pam_syslog(handle, LOG_ERR, "Unknown parameter '%s'.", argv[i]);
}
}
-#if 0
- if (!controller_set && controllers) {
+ if (!reset_controller_set && reset_controllers) {
char **l;
if (!(l = strv_new("cpu", NULL))) {
return -ENOMEM;
}
- *controllers = l;
+ *reset_controllers = l;
}
-#endif
if (controllers)
strv_remove(*controllers, "name=systemd");
+ if (reset_controllers)
+ strv_remove(*reset_controllers, "name=systemd");
+
if (kill_session && *kill_session && kill_user)
*kill_user = true;
+ if (!kill_exclude_users_set && kill_exclude_users) {
+ char **l;
+
+ if (!(l = strv_new("root", NULL))) {
+ pam_syslog(handle, LOG_ERR, "Out of memory");
+ return -ENOMEM;
+ }
+
+ *kill_exclude_users = l;
+ }
+
return 0;
}
* as the filesystems in question should be local, and only
* locally accessible, and most likely even tmpfs. */
- if (flock(fd, LOCK_EX) < 0)
+ if (flock(fd, LOCK_EX) < 0) {
+ close_nointr_nofail(fd);
return -errno;
+ }
return fd;
}
/* First attempt: let's use the session ID of the audit
* system, if it is available. */
- if (read_one_line_file("/proc/self/sessionid", &s) >= 0) {
- uint32_t u;
- int r;
+ if (have_effective_cap(CAP_AUDIT_CONTROL) > 0)
+ if (read_one_line_file("/proc/self/sessionid", &s) >= 0) {
+ uint32_t u;
+ int r;
- r = safe_atou32(s, &u);
- free(s);
+ r = safe_atou32(s, &u);
+ free(s);
- if (r >= 0 && u != (uint32_t) -1 && u > 0) {
- *mode = SESSION_ID_AUDIT;
- return (uint64_t) u;
+ if (r >= 0 && u != (uint32_t) -1 && u > 0) {
+ *mode = SESSION_ID_AUDIT;
+ return (uint64_t) u;
+ }
}
- }
/* Second attempt, use our own counter. */
if ((fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-session")) >= 0) {
ssize_t r;
/* We do a bit of endianess swapping here, just to be
- * sure. /var should be machine specific anyway, and
- * /var/run even mounted from tmpfs, so this
- * byteswapping should really not be necessary. But
- * then again, you never know, so let's avoid any
- * risk. */
+ * sure. /run should be machine specific anyway, and
+ * even mounted from tmpfs, so this byteswapping
+ * should really not be necessary. But then again, you
+ * never know, so let's avoid any risk. */
if (loop_read(fd, &counter, sizeof(counter), false) != sizeof(counter))
counter = 1;
/* Last attempt, pick a random value */
return (uint64_t) random_ull();
}
+
static int get_user_data(
pam_handle_t *handle,
const char **ret_username,
assert(ret_username);
assert(ret_pw);
- if (read_one_line_file("/proc/self/loginuid", &s) >= 0) {
- uint32_t u;
+ if (have_effective_cap(CAP_AUDIT_CONTROL) > 0) {
+ /* Only use audit login uid if we are executed with
+ * sufficient capabilities so that pam_loginuid could
+ * do its job. If we are lacking the CAP_AUDIT_CONTROL
+ * capabality we most likely are being run in a
+ * container and /proc/self/loginuid is useless since
+ * it probably contains a uid of the host system. */
+
+ if (read_one_line_file("/proc/self/loginuid", &s) >= 0) {
+ uint32_t u;
- r = safe_atou32(s, &u);
- free(s);
+ r = safe_atou32(s, &u);
+ free(s);
- if (r >= 0 && u != (uint32_t) -1 && u > 0) {
- have_loginuid = true;
- pw = pam_modutil_getpwuid(handle, u);
+ if (r >= 0 && u != (uint32_t) -1 && u > 0) {
+ have_loginuid = true;
+ pw = pam_modutil_getpwuid(handle, u);
+ }
}
}
return PAM_SUCCESS;
}
+static int reset_group(
+ pam_handle_t *handle,
+ const char *controller) {
+
+ int r;
+
+ assert(handle);
+
+ if ((r = cg_attach(controller, "/", 0)) < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to reset cgroup for controller %s: %s", controller, strerror(-r));
+ return PAM_SESSION_ERR;
+ }
+
+ return PAM_SUCCESS;
+}
+
_public_ PAM_EXTERN int pam_sm_open_session(
pam_handle_t *handle,
int flags,
char *buf = NULL;
int lock_fd = -1;
bool create_session = true;
- char **controllers = NULL, **c;
+ char **controllers = NULL, **reset_controllers = NULL, **c;
+ char *cgroup_user_tree = NULL;
assert(handle);
if (sd_booted() <= 0)
return PAM_SUCCESS;
- if (parse_argv(handle, argc, argv, &create_session, NULL, NULL, NULL, &controllers) < 0)
+ if (parse_argv(handle,
+ argc, argv,
+ &create_session, NULL, NULL,
+ &controllers, &reset_controllers,
+ NULL, NULL) < 0)
return PAM_SESSION_ERR;
if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS)
goto finish;
+ if ((r = cg_get_user_path(&cgroup_user_tree)) < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to determine user cgroup tree: %s", strerror(-r));
+ r = PAM_SYSTEM_ERR;
+ goto finish;
+ }
+
if (safe_mkdir(RUNTIME_DIR "/user", 0755, 0, 0) < 0) {
pam_syslog(handle, LOG_ERR, "Failed to create runtime directory: %m");
r = PAM_SYSTEM_ERR;
goto finish;
}
- /* Create /var/run/$USER */
+ /* Create /run/user/$USER */
free(buf);
if (asprintf(&buf, RUNTIME_DIR "/user/%s", username) < 0) {
r = PAM_BUF_ERR;
}
}
- r = asprintf(&buf, "/user/%s/%s", username, id);
+ r = asprintf(&buf, "%s/%s/%s", cgroup_user_tree, username, id);
} else
- r = asprintf(&buf, "/user/%s/master", username);
+ r = asprintf(&buf, "%s/%s/master", cgroup_user_tree, username);
if (r < 0) {
r = PAM_BUF_ERR;
STRV_FOREACH(c, controllers)
create_user_group(handle, *c, buf, pw, true, false);
+ STRV_FOREACH(c, reset_controllers)
+ reset_group(handle, *c);
+
r = PAM_SUCCESS;
finish:
close_nointr_nofail(lock_fd);
strv_free(controllers);
+ strv_free(reset_controllers);
+
+ free(cgroup_user_tree);
return r;
}
return !!remains;
}
+static bool check_user_lists(
+ pam_handle_t *handle,
+ uid_t uid,
+ char **kill_only_users,
+ char **kill_exclude_users) {
+
+ const char *name = NULL;
+ char **l;
+
+ assert(handle);
+
+ if (uid == 0)
+ name = "root"; /* Avoid obvious NSS requests, to suppress network traffic */
+ else {
+ struct passwd *pw;
+
+ if ((pw = pam_modutil_getpwuid(handle, uid)))
+ name = pw->pw_name;
+ }
+
+ STRV_FOREACH(l, kill_exclude_users) {
+ uint32_t id;
+
+ if (safe_atou32(*l, &id) >= 0)
+ if ((uid_t) id == uid)
+ return false;
+
+ if (name && streq(name, *l))
+ return false;
+ }
+
+ if (strv_isempty(kill_only_users))
+ return true;
+
+ STRV_FOREACH(l, kill_only_users) {
+ uint32_t id;
+
+ if (safe_atou32(*l, &id) >= 0)
+ if ((uid_t) id == uid)
+ return true;
+
+ if (name && streq(name, *l))
+ return true;
+ }
+
+ return false;
+}
+
_public_ PAM_EXTERN int pam_sm_close_session(
pam_handle_t *handle,
int flags,
const char *username = NULL;
bool kill_session = false;
bool kill_user = false;
- bool keep_root = true;
int lock_fd = -1, r;
char *session_path = NULL, *nosession_path = NULL, *user_path = NULL;
const char *id;
struct passwd *pw;
const void *created = NULL;
- char **controllers = NULL, **c;
+ char **controllers = NULL, **c, **kill_only_users = NULL, **kill_exclude_users = NULL;
+ char *cgroup_user_tree = NULL;
assert(handle);
if (sd_booted() <= 0)
return PAM_SUCCESS;
- if (parse_argv(handle, argc, argv, NULL, &kill_session, &kill_user, &keep_root, &controllers) < 0)
+ if (parse_argv(handle,
+ argc, argv,
+ NULL, &kill_session, &kill_user,
+ &controllers, NULL,
+ &kill_only_users, &kill_exclude_users) < 0)
return PAM_SESSION_ERR;
if ((r = get_user_data(handle, &username, &pw)) != PAM_SUCCESS)
goto finish;
+ if ((r = cg_get_user_path(&cgroup_user_tree)) < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to determine user cgroup tree: %s", strerror(-r));
+ r = PAM_SYSTEM_ERR;
+ goto finish;
+ }
+
if ((lock_fd = open_file_and_lock(RUNTIME_DIR "/user/.pam-systemd-lock")) < 0) {
pam_syslog(handle, LOG_ERR, "Failed to lock runtime directory: %m");
r = PAM_SYSTEM_ERR;
}
/* We are probably still in some session/user dir. Move ourselves out of the way as first step */
- if ((r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, "/user", 0)) < 0)
+ if ((r = cg_attach(SYSTEMD_CGROUP_CONTROLLER, cgroup_user_tree, 0)) < 0)
pam_syslog(handle, LOG_ERR, "Failed to move us away: %s", strerror(-r));
STRV_FOREACH(c, controllers)
- if ((r = cg_attach(*c, "/user", 0)) < 0)
+ if ((r = cg_attach(*c, cgroup_user_tree, 0)) < 0)
pam_syslog(handle, LOG_ERR, "Failed to move us away in %s hierarchy: %s", *c, strerror(-r));
- if (asprintf(&user_path, "/user/%s", username) < 0) {
+ if (asprintf(&user_path, "%s/%s", cgroup_user_tree, username) < 0) {
r = PAM_BUF_ERR;
goto finish;
}
if ((id = pam_getenv(handle, "XDG_SESSION_ID")) && created) {
- if (asprintf(&session_path, "/user/%s/%s", username, id) < 0 ||
- asprintf(&nosession_path, "/user/%s/master", username) < 0) {
+ if (asprintf(&session_path, "%s/%s/%s", cgroup_user_tree, username, id) < 0 ||
+ asprintf(&nosession_path, "%s/%s/master", cgroup_user_tree, username) < 0) {
r = PAM_BUF_ERR;
goto finish;
}
- if (kill_session && (pw->pw_uid != 0 || !keep_root)) {
+ if (kill_session && check_user_lists(handle, pw->pw_uid, kill_only_users, kill_exclude_users)) {
pam_syslog(handle, LOG_INFO, "Killing remaining processes of user session %s of %s.", id, username);
/* Kill processes in session cgroup, and delete it */
pam_syslog(handle, LOG_ERR, "Failed to determine whether a session remains: %s", strerror(-r));
/* Kill user processes not attached to any session */
- if (kill_user && r == 0 && (pw->pw_uid != 0 || !keep_root)) {
+ if (kill_user && r == 0 && check_user_lists(handle, pw->pw_uid, kill_only_users, kill_exclude_users)) {
/* Kill user cgroup */
if ((r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, user_path, true)) < 0)
free(user_path);
strv_free(controllers);
+ strv_free(kill_exclude_users);
+ strv_free(kill_only_users);
+
+ free(cgroup_user_tree);
return r;
}
~ianmdlvl / elogind.git / blobdiff