sd_bus_query_sender_creds(3) — Linux manual page


SD_BUS_Q...DER_CREDS(3) sd_bus_query_sender_credsSD_BUS_Q...DER_CREDS(3)

NAME         top

       sd_bus_query_sender_creds, sd_bus_query_sender_privilege - Query
       bus message sender credentials/privileges

SYNOPSIS         top

       #include <systemd/sd-bus.h>

       int sd_bus_query_sender_creds(sd_bus_message *m, uint64_t mask,
                                     sd_bus_creds **creds);

       sd_bus_error* sd_bus_query_sender_privilege(sd_bus_message *m,
                                                   int capability);

DESCRIPTION         top

       sd_bus_query_sender_creds() returns the credentials of the
       message m. The mask parameter is a combo of SD_BUS_CREDS_* flags
       that indicate which credential info the caller is interested in.
       See sd_bus_creds_new_from_pid(3) for a list of possible flags.
       First, this message checks if the requested credentials are
       attached to the message itself. If not, but the message contains
       the pid of the sender and the caller specified the
       SD_BUS_CREDS_AUGMENT flag, this function tries to figure out the
       missing credentials via other means (starting from the pid). If
       the pid isn't available but the message has a sender, this
       function calls sd_bus_get_name_creds(3) to get the requested
       credentials. If the message has no sender (when a direct
       connection is used), this function calls
       sd_bus_get_owner_creds(3) to get the requested credentials. On
       success, the requested credentials are stored in creds. Ownership
       of the credentials object in creds is transferred to the caller
       and should be freed by calling sd_bus_creds_unref(3).

       sd_bus_query_sender_privilege() checks if the message m has the
       requested privileges. If capability is a non-negative integer,
       this function checks if the message has the capability with the
       same value. See capabilities(7) for a list of capabilities. If
       capability is a negative integer, this function returns whether
       the sender of the message runs as the same user as the receiver
       of the message, or if the sender of the message runs as root and
       the receiver of the message does not run as root. On success and
       if the message has the requested privileges, this function
       returns a positive integer. If the message does not have the
       requested privileges, this function returns zero.

RETURN VALUE         top

       On success, these functions return a non-negative integer. On
       failure, they return a negative errno-style error code.

       Returned errors may indicate the following problems:

           The message m or an output parameter is NULL.

           Added in version 246.

           The bus of m is not connected.

           Added in version 246.

           The bus of m was created in a different process, library or
           module instance.

           Added in version 246.

           The message m is not sealed.

           Added in version 246.

NOTES         top

       Functions described here are available as a shared library, which
       can be compiled against and linked to with the
       libsystemd pkg-config(1) file.

       The code described here uses getenv(3), which is declared to be
       not multi-thread-safe. This means that the code calling the
       functions described here must not call setenv(3) from a parallel
       thread. It is recommended to only do calls to setenv() from an
       early phase of the program when no other threads have been

HISTORY         top

       sd_bus_query_sender_creds() and sd_bus_query_sender_privilege()
       were added in version 246.

SEE ALSO         top

       systemd(1), sd-bus(3), sd_bus_creds_new_from_pid(3),
       sd_bus_get_name_creds(3), sd_bus_get_owner_creds(3),
       sd_bus_creds_unref(3), capabilities(7)

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨⟩.  If you have
       a bug report for this manual page, see
       This page was obtained from the project's upstream Git repository
       ⟨⟩ on 2023-12-22.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2023-12-22.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

systemd 255                                      SD_BUS_Q...DER_CREDS(3)

Pages that refer to this page: sd-bus(3)sd_bus_add_object(3)systemd.directives(7)systemd.index(7)