Struct sequoia_openpgp::types::Features

pub struct Features(_);

Describes the features supported by an OpenPGP implementation.

The feature flags are defined in Section 5.2.3.24 of RFC 4880, and Section 5.2.3.25 of RFC 4880bis.

The feature flags are set by the user’s OpenPGP implementation to signal to any senders what features the implementation supports.

A note on equality

PartialEq compares the serialized form of the two feature sets. If you prefer to compare two feature sets for semantic equality, you should use Features::normalized_eq. The difference between semantic equality and serialized equality is that semantic equality ignores differences in the amount of padding.

Examples

use sequoia_openpgp as openpgp;
use openpgp::cert::prelude::*;
use openpgp::policy::StandardPolicy;

let p = &StandardPolicy::new();

match cert.with_policy(p, None)?.primary_userid()?.features() {
    Some(features) => {
        println!("Certificate holder's supported features:");
        assert!(features.supports_mdc());
        assert!(!features.supports_aead());
    }
    None => {
        println!("Certificate Holder did not specify any features.");
    }
}

Implementations

impl Features

pub fn new<B>(bytes: B) -> Self where
    B: AsRef<[u8]>, 

Creates a new instance from bytes.

This does not remove any trailing padding from bytes.

pub fn empty() -> Self

Returns an empty feature set.

pub fn sequoia() -> Self

Returns a feature set describing Sequoia’s capabilities.

pub fn normalized_eq(&self, other: &Self) -> bool

Compares two feature sets for semantic equality.

Features’ implementation of PartialEq compares two feature sets for serialized equality. That is, the PartialEq implementation considers two feature sets to not be equal if they have different amounts of padding. This comparison function ignores padding.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let a = Features::new(&[0x1]);
let b = Features::new(&[0x1, 0x0]);

assert!(a != b);
assert!(a.normalized_eq(&b));

pub fn get(&self, bit: usize) -> bool

Returns whether the specified feature flag is set.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

// Feature flags 0 and 2.
let f = Features::new(&[0x5]);

assert!(f.get(0));
assert!(! f.get(1));
assert!(f.get(2));
assert!(! f.get(3));
assert!(! f.get(8));
assert!(! f.get(80));

pub fn set(self, bit: usize) -> Self

Sets the specified feature flag.

This also clears any padding (trailing NUL bytes).

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::empty().set(0).set(2);

assert!(f.get(0));
assert!(! f.get(1));
assert!(f.get(2));
assert!(! f.get(3));

pub fn clear(self, bit: usize) -> Self

Clears the specified feature flag.

This also clears any padding (trailing NUL bytes).

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::empty().set(0).set(2).clear(2);

assert!(f.get(0));
assert!(! f.get(1));
assert!(! f.get(2));
assert!(! f.get(3));

pub fn supports_mdc(&self) -> bool

Returns whether the MDC feature flag is set.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::empty();

assert!(! f.supports_mdc());

pub fn set_mdc(self) -> Self

Sets the MDC feature flag.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::empty().set_mdc();

assert!(f.supports_mdc());

pub fn clear_mdc(self) -> Self

Clears the MDC feature flag.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::new(&[0x1]);
assert!(f.supports_mdc());

let f = f.clear_mdc();
assert!(! f.supports_mdc());

pub fn supports_aead(&self) -> bool

Returns whether the AEAD feature flag is set.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::empty();

assert!(! f.supports_aead());

pub fn set_aead(self) -> Self

Sets the AEAD feature flag.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::empty().set_aead();

assert!(f.supports_aead());

pub fn clear_aead(self) -> Self

Clears the AEAD feature flag.

Examples

use sequoia_openpgp as openpgp;
use openpgp::types::Features;

let f = Features::new(&[0x2]);
assert!(f.supports_aead());

let f = f.clear_aead();
assert!(! f.supports_aead());

Trait Implementations

impl Clone for Features

fn clone(&self) -> Features

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Features

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

Formats the value using the given formatter.

impl Hash for Features

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl Ord for Features

fn cmp(&self, other: &Features) -> Ordering

This method returns an Ordering between self and other.

#[must_use]

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<Features> for Features

fn eq(&self, other: &Features) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Features) -> bool

This method tests for !=.

impl PartialOrd<Features> for Features

fn partial_cmp(&self, other: &Features) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

#[must_use]

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use]

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use]

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use]

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for Features

impl StructuralEq for Features

impl StructuralPartialEq for Features