based on the <varname>$DISPLAY</varname> variable.</para>
</refsect1>
+ <refsect1>
+ <title>Session limits</title>
+
+ <para>PAM modules earlier in the stack, that is those that come before <command>pam_systemd.so</command>,
+ can set session scope limits using the PAM context objects. The data for these objects is provided as NUL-terminated C strings
+ and maps directly to the respective unit resource control directives. Note that these limits apply to individual sessions of the user,
+ they do not apply to all user processes as a combined whole. In particular, the per-user <command>user@.service</command> unit instance,
+ which runs the <command>systemd --user</command> manager process and its children, and is tracked outside of any session, being shared
+ by all the user's sessions, is not covered by these limits.
+ </para>
+
+ <para> See
+ <citerefentry><refentrytitle>systemd.resource-control</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information about the resources.
+ Also, see <citerefentry><refentrytitle>pam_set_data</refentrytitle><manvolnum>3</manvolnum></citerefentry> for additional information about how to set
+ the context objects.
+ </para>
+
+ <variablelist>
+ <varlistentry>
+ <term><varname>systemd.memory_max</varname></term>
+
+ <listitem><para>Sets unit <varname>MemoryMax=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.tasks_max</varname></term>
+
+ <listitem><para>Sets unit <varname>TasksMax=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.cpu_weight</varname></term>
+
+ <listitem><para>Sets unit <varname>CPUWeight=</varname>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><varname>systemd.io_weight</varname></term>
+
+ <listitem><para>Sets unit <varname>IOWeight=</varname>.</para></listitem>
+ </varlistentry>
+ </variablelist>
+
+ <para>Example data as can be provided from an another PAM module:
+ <programlisting>
+pam_set_data(handle, "systemd.memory_max", (void *)"200M", cleanup);
+pam_set_data(handle, "systemd.tasks_max", (void *)"50", cleanup);
+pam_set_data(handle, "systemd.cpu_weight", (void *)"100", cleanup);
+pam_set_data(handle, "systemd.io_weight", (void *)"340", cleanup);
+ </programlisting>
+ </para>
+
+ </refsect1>
+
<refsect1>
<title>Example</title>
#include "terminal-util.h"
#include "util.h"
#include "path-util.h"
+#include "cgroup-util.h"
static int parse_argv(
pam_handle_t *handle,
return r;
}
+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 0;
+
+ if (streq(limit, "infinity")) {
+ r = sd_bus_message_append(m, "(sv)", "MemoryMax", "t", (uint64_t)-1);
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
+ return r;
+ }
+ } else {
+ r = parse_percent(limit);
+ if (r >= 0) {
+ r = sd_bus_message_append(m, "(sv)", "MemoryMaxScale", "u", (uint32_t) (((uint64_t) UINT32_MAX * r) / 100U));
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
+ return r;
+ }
+ } else {
+ r = parse_size(limit, 1024, &val);
+ if (r >= 0) {
+ r = sd_bus_message_append(m, "(sv)", "MemoryMax", "t", val);
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
+ return r;
+ }
+ } else
+ pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.limit: %s, ignoring.", limit);
+ }
+ }
+
+ return 0;
+}
+
+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 0;
+
+ r = safe_atou64(limit, &val);
+ if (r >= 0) {
+ r = sd_bus_message_append(m, "(sv)", "TasksMax", "t", val);
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
+ return r;
+ }
+ } else
+ pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.limit: %s, ignoring.", limit);
+
+ return 0;
+}
+
+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)) {
+ r = cg_weight_parse(limit, &val);
+ if (r >= 0) {
+ r = sd_bus_message_append(m, "(sv)", field, "t", val);
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
+ return r;
+ }
+ } else if (streq(field, "CPUWeight"))
+ pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.cpu_weight: %s, ignoring.", limit);
+ else
+ pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.io_weight: %s, ignoring.", limit);
+ }
+
+ return 0;
+}
+
_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 *reply = NULL;
+ _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *reply = NULL;
const char
*username, *id, *object_path, *runtime_path,
*service = NULL,
*remote_user = NULL, *remote_host = NULL,
*seat = NULL,
*type = NULL, *class = NULL,
- *class_pam = NULL, *type_pam = NULL, *cvtnr = NULL, *desktop = NULL;
+ *class_pam = NULL, *type_pam = NULL, *cvtnr = NULL, *desktop = NULL,
+ *memory_max = NULL, *tasks_max = NULL, *cpu_weight = NULL, *io_weight = NULL;
_cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
int session_fd = -1, existing, r;
bool debug = false, remote;
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);
+
/* Talk to logind over the message bus */
r = sd_bus_open_system(&bus);
return PAM_SESSION_ERR;
}
- if (debug)
+ 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",
pw->pw_uid, getpid_cached(),
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",
+ strna(memory_max), strna(tasks_max), strna(cpu_weight), strna(io_weight));
+ }
+
+ r = sd_bus_message_new_method_call(
+ bus,
+ &m,
+ "org.freedesktop.login1",
+ "/org/freedesktop/login1",
+ "org.freedesktop.login1.Manager",
+ "CreateSession");
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to create CreateSession method call: %s", strerror(-r));
+ return PAM_SESSION_ERR;
+ }
+
+ r = sd_bus_message_append(m, "uusssssussbss",
+ (uint32_t) pw->pw_uid,
+ (uint32_t) getpid_cached(),
+ service,
+ type,
+ class,
+ desktop,
+ seat,
+ vtnr,
+ tty,
+ display,
+ remote,
+ remote_user,
+ remote_host);
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
+ return PAM_SESSION_ERR;
+ }
+
+ r = sd_bus_message_open_container(m, 'a', "(sv)");
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to open message container: %s", strerror(-r));
+ return PAM_SYSTEM_ERR;
+ }
+
+ r = append_session_memory_max(handle, m, memory_max);
+ if (r < 0)
+ return PAM_SESSION_ERR;
+
+ r = append_session_tasks_max(handle, m, tasks_max);
+ if (r < 0)
+ return PAM_SESSION_ERR;
+
+ r = append_session_cg_weight(handle, m, cpu_weight, "CPUWeight");
+ if (r < 0)
+ return PAM_SESSION_ERR;
+
+ r = append_session_cg_weight(handle, m, io_weight, "IOWeight");
+ if (r < 0)
+ return PAM_SESSION_ERR;
+
+ r = sd_bus_message_close_container(m);
+ if (r < 0) {
+ pam_syslog(handle, LOG_ERR, "Failed to close message container: %s", strerror(-r));
+ return PAM_SYSTEM_ERR;
+ }
- r = sd_bus_call_method(bus,
- "org.freedesktop.login1",
- "/org/freedesktop/login1",
- "org.freedesktop.login1.Manager",
- "CreateSession",
- &error,
- &reply,
- "uusssssussbssa(sv)",
- (uint32_t) pw->pw_uid,
- (uint32_t) getpid_cached(),
- service,
- type,
- class,
- desktop,
- seat,
- vtnr,
- tty,
- display,
- remote,
- remote_user,
- remote_host,
- 0);
+ r = sd_bus_call(bus, m, 0, &error, &reply);
if (r < 0) {
if (sd_bus_error_has_name(&error, BUS_ERROR_SESSION_BUSY)) {
pam_syslog(handle, LOG_DEBUG, "Cannot create session: %s", bus_error_message(&error, r));
projects / thirdparty / systemd.git / commitdiff
