| SD_BUS_QUERY_SENDER_CREDS(3) | sd_bus_query_sender_creds | SD_BUS_QUERY_SENDER_CREDS(3) |
.SH "NAME" sd_bus_query_sender_creds, sd_bus_query_sender_privilege
- Query bus message sender credentials/privileges
.SH "SYNOPSIS"
#include <systemd/sd-bus.h>
.HP 720u int
sd_bus_query_sender_creds(sd_bus_message *m,
uint64_t mask,
sd_bus_creds **creds);
.HP 1056u sd_bus_error*
sd_bus_query_sender_privilege(sd_bus_message *m,
int capability);
.SH "DESCRIPTION"
.PP 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 is not 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).
.PP 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.
.SH "RETURN VALUE"
.PP On success, these functions return a non-negative integer. On failure,
they return a negative errno-style error code.
.SS "Errors"
.PP Returned errors may indicate the following problems:
.PP -EINVAL
The message m or an output parameter is NULL.
Added in version 246.
.RE
.PP -ENOTCONN
The bus of m is not connected.
Added in version 246.
.RE
.PP -ECHILD
The bus of m was created in a different process, library or module
instance.
Added in version 246.
.RE
.PP -EPERM
The message m is not sealed.
Added in version 246.
.RE
.SH "NOTES"
.PP Functions described here are available as a shared library, which can be
compiled against and linked to with the
libsystemd pkg-config(1) file.
.PP All functions listed here are thread-agnostic and only a single thread
may operate on a given object at any given time. Different threads may
access the same object at different times. Multiple independent objects may
be used from different threads in parallel.
.PP 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 started.
.SH "HISTORY"
.PP sd_bus_query_sender_creds() and
sd_bus_query_sender_privilege() were added in version 246.
.SH "SEE ALSO"
.PP 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)
| systemd 262.2 |