systemd A monkey with a typewriter Zbigniew Jędrzejewski-Szmek zbyszek@in.waw.pl sd_bus_creds_get_pid 3 sd_bus_creds_get_pid sd_bus_creds_get_tid sd_bus_creds_get_uid sd_bus_creds_get_gid sd_bus_creds_get_comm sd_bus_creds_get_tid_comm sd_bus_creds_get_exe sd_bus_creds_get_cmdline sd_bus_creds_get_cgroup sd_bus_creds_get_unit sd_bus_creds_get_user_unit sd_bus_creds_get_slice sd_bus_creds_get_session sd_bus_creds_get_owner_uid sd_bus_creds_has_effective_cap sd_bus_creds_has_permitted_cap sd_bus_creds_has_inheritable_cap sd_bus_creds_has_bounding_cap sd_bus_creds_get_selinux_context sd_bus_creds_get_audit_session_id sd_bus_creds_get_audit_login_uid sd_bus_creds_get_unique_name sd_bus_creds_get_well_known_names sd_bus_creds_get_connection_name Retrieve fields from a credentials object #include <systemd/sd-bus.h> int sd_bus_creds_get_pid sd_bus_creds *c pid_t *pid int sd_bus_creds_get_tid sd_bus_creds *c pid_t *tid int sd_bus_creds_get_pid sd_bus_creds *c uid_t *uid int sd_bus_creds_get_gid sd_bus_creds *c gid_t *gid int sd_bus_creds_get_comm sd_bus_creds *c const char **comm int sd_bus_creds_get_tid_comm sd_bus_creds *c const char **comm int sd_bus_creds_get_exe sd_bus_creds *c const char **exe int sd_bus_creds_get_cmdline sd_bus_creds *c char ***cmdline int sd_bus_creds_get_cgroup sd_bus_creds *c const char **cgroup int sd_bus_creds_get_unit sd_bus_creds *c const char **unit int sd_bus_creds_get_user_unit sd_bus_creds *c const char **unit int sd_bus_creds_get_slice sd_bus_creds *c const char **slice int sd_bus_creds_get_session sd_bus_creds *c const char **slice int sd_bus_creds_get_owner_uid sd_bus_creds *c uid_t *uid int sd_bus_creds_has_effective_cap sd_bus_creds *c int capability int sd_bus_creds_has_permitted_cap sd_bus_creds *c int capability int sd_bus_creds_has_inheritable_cap sd_bus_creds *c int capability int sd_bus_creds_has_bounding_cap sd_bus_creds *c int capability int sd_bus_creds_get_selinux_context sd_bus_creds *c const char **context int sd_bus_creds_get_audit_session_id sd_bus_creds *c uint32_t *sessionid int sd_bus_creds_get_audit_login_uid sd_bus_creds *c uid_t *loginuid int sd_bus_creds_get_unique_name sd_bus_creds *c const char **name int sd_bus_creds_get_well_known_names sd_bus_creds *c char ***name int sd_bus_creds_get_connection_name sd_bus_creds *c const char **name These functions return information from an sd_bus_creds object. It may be created with sd_bus_creds_new_from_pid3, in which case it will describe the specified process, or it may be created by sd_bus_get_owner_creds3, in which case it will describe the process at the other endpoint of a connection. sd_bus_creds_get_pid() will retrieve the PID (process identifier). sd_bus_creds_get_tid() will retrieve the TID (thread identifier). sd_bus_creds_get_uid() will retrieve the numeric UID (user identifier). sd_bus_creds_get_gid() will retrieve the numeric GID (group identifier). sd_bus_creds_get_comm() will retrieve the comm field (truncated name of the executable, as stored in /proc/pid/comm). sd_bus_creds_get_tid_comm() will retrieve the comm field of the thread (as stored in /proc/pid/task/tid/comm). sd_bus_creds_get_exe() will retrieve the path to the program (as stored in the /proc/pid/exe link, but with (deleted) suffix removed). sd_bus_creds_get_cmdline() will retrieve an array of command line arguments (as stored in /proc/pid/cmdline). sd_bus_creds_get_cgroup() will retrieve the cgroup path. See cgroups.txt. sd_bus_creds_get_unit() will retrieve the systemd unit name (in the system instance of systemd) that the process is part of. See systemd.unit5. sd_bus_creds_get_user_unit() will retrieve the systemd unit name (in the user instance of systemd) that the process is part of. See systemd.unit5. sd_bus_creds_get_slice() will retrieve the systemd slice (a unit in the system instance of systemd) that the process is part of. See systemd.slice5. sd_bus_creds_get_session() will retrieve the logind session that the process is part of. See systemd-logind.service8. sd_bus_creds_get_owner_uid() will retrieve the numeric UID (user identifier) of the user who owns the slice that the process is part of. See systemd.slice5 . sd_bus_creds_has_effective_cap() will check whether the capability specified by capability was set in the effective capabilities mask. A positive return value means that is was set, zero means that it was not set, and a negative return value signifies an error. See capabilities7 and Capabilities= and CapabilityBoundingSet= settings in systemd.exec5. sd_bus_creds_has_permitted_cap() is similar to sd_bus_creds_has_effective_cap(), but will check the permitted capabilities mask. sd_bus_creds_has_inheritable_cap() is similar to sd_bus_creds_has_effective_cap(), but will check the inheritable capabilities mask. sd_bus_creds_has_bounding_cap() is similar to sd_bus_creds_has_effective_cap(), but will check the bounding capabilities mask. sd_bus_creds_get_selinux_context() will retrieve the SELinux security context (label) of the process. sd_bus_creds_get_audit_session_id() will retrieve the audit session identifier of the process. sd_bus_creds_get_audit_login_uid() will retrieve the audit user login identifier (the identifier of the user who is "responsible" for the session). sd_bus_creds_get_unique_name() will retrieve the D-Bus unique name. See The D-Bus specification. sd_bus_creds_get_well_known_names() will retrieve the set of D-Bus well-known names. See The D-Bus specification. sd_bus_creds_get_connection_name() will retrieve a descriptive name of the bus connection of the peer. This name is useful to discern multiple bus connections by the same peer, and may be altered by the peer with the sd_bus_set_name()3 call. All functions that take a const char** parameter will store the answer there as an address of a NUL-terminated string. It will be valid as long as c remains valid, and should not be freed or modified by the caller. All functions that take a char*** parameter will store the answer there as an address of a an array of strings. Each invidividual string is NUL-terminated, and the array is NULL-terminated as a whole. It will be valid as long as c remains valid, and should not be freed or modified by the caller. On success, these calls return 0 or a positive integer. On failure, these calls return a negative errno-style error code. Returned errors may indicate the following problems: -ENODATA Given field is not available in c. -ENOENT Given field is not specified for the sender. This will be returned by sd_bus_get_unit(), sd_bus_get_user_unit(), sd_bus_get_slice(), sd_bus_get_session(), and sd_bus_get_name_creds_uid() if the sender is not part of a systemd system unit, systemd user unit, systemd slice, logind session, or a systemd user session. -ENXIO An error occurred in parsing cgroup paths. libsystemd might be out of sync with the running systemd version. -EINVAL Specified pointer parameter is NULL. -ENOMEM Memory allocation failed. sd_bus_open_user() and other functions described here are available as a shared library, which can be compiled and linked to with the libsystemd pkg-config1 file. systemd1, sd-bus3, fork2, execve2, credentials7, free3, proc5, systemd.journal-fields7