Struct Credentials 

pub struct Credentials {

    pub uid: uid_t,
    pub gid: gid_t,
    pub euid: uid_t,
    pub egid: gid_t,
    pub saved_uid: uid_t,
    pub saved_gid: gid_t,
    pub groups: Vec<gid_t>,
    pub fsuid: uid_t,
    pub fsgid: gid_t,
    pub cap_permitted: Capabilities,
    pub cap_effective: Capabilities,
    pub cap_inheritable: Capabilities,
    pub cap_bounding: Capabilities,
    pub cap_ambient: Capabilities,
    pub securebits: SecureBits,
    pub security_state: TaskAttrs,
}

Fields

uid: uid_t

gid: gid_t

euid: uid_t

egid: gid_t

saved_uid: uid_t

saved_gid: gid_t

groups: Vec<gid_t>

fsuid: uid_t

See https://man7.org/linux/man-pages/man2/setfsuid.2.html

fsgid: gid_t

See https://man7.org/linux/man-pages/man2/setfsgid.2.html

cap_permitted: Capabilities

From https://man7.org/linux/man-pages/man7/capabilities.7.html

This is a limiting superset for the effective capabilities that the thread may assume. It is also a limiting superset for the capabilities that may be added to the inheritable set by a thread that does not have the CAP_SETPCAP capability in its effective set.

If a thread drops a capability from its permitted set, it can never reacquire that capability (unless it execve(2)s either a set-user-ID-root program, or a program whose associated file capabilities grant that capability).

cap_effective: Capabilities

From https://man7.org/linux/man-pages/man7/capabilities.7.html

This is the set of capabilities used by the kernel to perform permission checks for the thread.

cap_inheritable: Capabilities

From https://man7.org/linux/man-pages/man7/capabilities.7.html

This is a set of capabilities preserved across an execve(2). Inheritable capabilities remain inheritable when executing any program, and inheritable capabilities are added to the permitted set when executing a program that has the corresponding bits set in the file inheritable set.

Because inheritable capabilities are not generally preserved across execve(2) when running as a non-root user, applications that wish to run helper programs with elevated capabilities should consider using ambient capabilities, described below.

cap_bounding: Capabilities

From https://man7.org/linux/man-pages/man7/capabilities.7.html

The capability bounding set is a mechanism that can be used to limit the capabilities that are gained during execve(2).

Since Linux 2.6.25, this is a per-thread capability set. In older kernels, the capability bounding set was a system wide attribute shared by all threads on the system.

cap_ambient: Capabilities

From https://man7.org/linux/man-pages/man7/capabilities.7.html

This is a set of capabilities that are preserved across an execve(2) of a program that is not privileged. The ambient capability set obeys the invariant that no capability can ever be ambient if it is not both permitted and inheritable.

Executing a program that changes UID or GID due to the set-user-ID or set-group-ID bits or executing a program that has any file capabilities set will clear the ambient set.

securebits: SecureBits

From https://man7.org/linux/man-pages/man7/capabilities.7.html

Starting with kernel 2.6.26, and with a kernel in which file capabilities are enabled, Linux implements a set of per-thread securebits flags that can be used to disable special handling of capabilities for UID 0 (root).

The securebits flags can be modified and retrieved using the prctl(2) PR_SET_SECUREBITS and PR_GET_SECUREBITS operations. The CAP_SETPCAP capability is required to modify the flags.

security_state: TaskAttrs

The SELinux security state of the task.

Implementations

impl Credentials

pub fn root() -> Arc<Self>

Creates a set of credentials with all possible permissions and capabilities.

pub fn with_ids(uid: uid_t, gid: gid_t) -> Credentials

Creates a set of credentials with the given uid and gid. If the uid is 0, the credentials will grant superuser access.

pub fn is_in_group(&self, gid: gid_t) -> bool

pub fn set_securebits(&mut self, securebits: SecureBits) -> Result<(), Errno>

Updates the securebits field, taking into account *_LOCKED bits.

pub fn exec(&mut self, prev: &Credentials) -> bool

pub fn as_fscred(&self) -> FsCred

pub fn euid_as_fscred(&self) -> FsCred

pub fn uid_as_fscred(&self) -> FsCred

pub fn update_capabilities(&mut self, prev: &Credentials)

Adjusts the capability sets (permitted, effective, and ambient) of these credentials to reflect changes in user IDs (UID, EUID, Saved UID, or FSUID) from a previous state.

This method compares the current state of these credentials against the prev credentials to implement the Linux security model rules for UID transitions (as described in capabilities(7) under “Effect of user ID changes on capabilities”). It is typically called when preparing a new set of Credentials during setuid() family syscalls or during exec after UID/GID bits have been applied.

Trait Implementations

impl Clone for Credentials

fn clone(&self) -> Credentials

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Credentials

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<Credentials> for FsCred

fn from(c: Credentials) -> Self

Converts to this type from the input type.