Struct sequoia_openpgp::packet::signature::subpacket::CLOCK_SKEW_TOLERANCE

pub struct CLOCK_SKEW_TOLERANCE { /* private fields */ }

The default amount of tolerance to use when comparing some timestamps.

Used by Subpacket::signature_alive.

When determining whether a timestamp generated on another machine is valid now, we need to account for clock skew. (Note: you don’t normally need to consider clock skew when evaluating a signature’s validity at some time in the past.)

We tolerate half an hour of skew based on the following anecdote: In 2019, a developer using Sequoia in a Windows VM running inside of Virtual Box on Mac OS X reported that he typically observed a few minutes of clock skew and occasionally saw over 20 minutes of clock skew.

Note: when new messages override older messages, and their signatures are evaluated at some arbitrary point in time, an application may not see a consistent state if it uses a tolerance. Consider an application that has two messages and wants to get the current message at time te:

• t0: message 0
• te: “get current message”
• t1: message 1

If te is close to t1, then t1 may be considered valid, which is probably not what you want.

Methods from Deref<Target = Duration>

pub const SECOND: Duration = Duration::from_secs(1)

pub const MILLISECOND: Duration = Duration::from_millis(1)

pub const MICROSECOND: Duration = Duration::from_micros(1)

pub const NANOSECOND: Duration = Duration::from_nanos(1)

pub const ZERO: Duration = Duration::from_nanos(0)

pub const MAX: Duration = Duration::new(u64::MAX, NANOS_PER_SEC - 1)

pub fn is_zero(&self) -> bool

Returns true if this Duration spans no time.

Examples

use std::time::Duration;

assert!(Duration::ZERO.is_zero());
assert!(Duration::new(0, 0).is_zero());
assert!(Duration::from_nanos(0).is_zero());
assert!(Duration::from_secs(0).is_zero());

assert!(!Duration::new(1, 1).is_zero());
assert!(!Duration::from_nanos(1).is_zero());
assert!(!Duration::from_secs(1).is_zero());

pub fn as_secs(&self) -> u64

Returns the number of whole seconds contained by this Duration.

The returned value does not include the fractional (nanosecond) part of the duration, which can be obtained using subsec_nanos.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_secs(), 5);

To determine the total number of seconds represented by the Duration, use as_secs in combination with subsec_nanos:

use std::time::Duration;

let duration = Duration::new(5, 730023852);

assert_eq!(5.730023852,
           duration.as_secs() as f64
           + duration.subsec_nanos() as f64 * 1e-9);

pub fn subsec_millis(&self) -> u32

Returns the fractional part of this Duration, in whole milliseconds.

This method does not return the length of the duration when represented by milliseconds. The returned number always represents a fractional portion of a second (i.e., it is less than one thousand).

Examples

use std::time::Duration;

let duration = Duration::from_millis(5432);
assert_eq!(duration.as_secs(), 5);
assert_eq!(duration.subsec_millis(), 432);

pub fn subsec_micros(&self) -> u32

Returns the fractional part of this Duration, in whole microseconds.

This method does not return the length of the duration when represented by microseconds. The returned number always represents a fractional portion of a second (i.e., it is less than one million).

Examples

use std::time::Duration;

let duration = Duration::from_micros(1_234_567);
assert_eq!(duration.as_secs(), 1);
assert_eq!(duration.subsec_micros(), 234_567);

pub fn subsec_nanos(&self) -> u32

Returns the fractional part of this Duration, in nanoseconds.

This method does not return the length of the duration when represented by nanoseconds. The returned number always represents a fractional portion of a second (i.e., it is less than one billion).

Examples

use std::time::Duration;

let duration = Duration::from_millis(5010);
assert_eq!(duration.as_secs(), 5);
assert_eq!(duration.subsec_nanos(), 10_000_000);

pub fn as_millis(&self) -> u128

Returns the total number of whole milliseconds contained by this Duration.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_millis(), 5730);

pub fn as_micros(&self) -> u128

Returns the total number of whole microseconds contained by this Duration.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_micros(), 5730023);

pub fn as_nanos(&self) -> u128

Returns the total number of nanoseconds contained by this Duration.

Examples

use std::time::Duration;

let duration = Duration::new(5, 730023852);
assert_eq!(duration.as_nanos(), 5730023852);

pub fn as_secs_f64(&self) -> f64

Returns the number of seconds contained by this Duration as f64.

The returned value does include the fractional (nanosecond) part of the duration.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.as_secs_f64(), 2.7);

pub fn as_secs_f32(&self) -> f32

Returns the number of seconds contained by this Duration as f32.

The returned value does include the fractional (nanosecond) part of the duration.

Examples

use std::time::Duration;

let dur = Duration::new(2, 700_000_000);
assert_eq!(dur.as_secs_f32(), 2.7);

Trait Implementations

impl Deref for CLOCK_SKEW_TOLERANCE

type Target = Duration

The resulting type after dereferencing.

fn deref(&self) -> &Duration

Dereferences the value.

impl LazyStatic for CLOCK_SKEW_TOLERANCE