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#![cfg_attr(docsrs, feature(doc_cfg))]
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#![doc = include_str!("../README.md")]
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// @@ begin lint list maintained by maint/add_warning @@
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#![allow(renamed_and_removed_lints)] // @@REMOVE_WHEN(ci_arti_stable)
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#![allow(unknown_lints)] // @@REMOVE_WHEN(ci_arti_nightly)
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#![warn(missing_docs)]
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#![warn(noop_method_call)]
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#![warn(unreachable_pub)]
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#![warn(clippy::all)]
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#![deny(clippy::await_holding_lock)]
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#![deny(clippy::cargo_common_metadata)]
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#![deny(clippy::cast_lossless)]
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#![deny(clippy::checked_conversions)]
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#![warn(clippy::cognitive_complexity)]
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#![deny(clippy::debug_assert_with_mut_call)]
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#![deny(clippy::exhaustive_enums)]
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#![deny(clippy::exhaustive_structs)]
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#![deny(clippy::expl_impl_clone_on_copy)]
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#![deny(clippy::fallible_impl_from)]
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#![deny(clippy::implicit_clone)]
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#![deny(clippy::large_stack_arrays)]
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#![warn(clippy::manual_ok_or)]
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#![deny(clippy::missing_docs_in_private_items)]
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#![warn(clippy::needless_borrow)]
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#![warn(clippy::needless_pass_by_value)]
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#![warn(clippy::option_option)]
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#![deny(clippy::print_stderr)]
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#![deny(clippy::print_stdout)]
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#![warn(clippy::rc_buffer)]
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#![deny(clippy::ref_option_ref)]
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#![warn(clippy::semicolon_if_nothing_returned)]
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#![warn(clippy::trait_duplication_in_bounds)]
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#![deny(clippy::unchecked_time_subtraction)]
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#![deny(clippy::unnecessary_wraps)]
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#![warn(clippy::unseparated_literal_suffix)]
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#![deny(clippy::unwrap_used)]
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#![deny(clippy::mod_module_files)]
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#![allow(clippy::let_unit_value)] // This can reasonably be done for explicitness
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#![allow(clippy::uninlined_format_args)]
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#![allow(clippy::significant_drop_in_scrutinee)] // arti/-/merge_requests/588/#note_2812945
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#![allow(clippy::result_large_err)] // temporary workaround for arti#587
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#![allow(clippy::needless_raw_string_hashes)] // complained-about code is fine, often best
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#![allow(clippy::needless_lifetimes)] // See arti#1765
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#![allow(mismatched_lifetime_syntaxes)] // temporary workaround for arti#2060
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#![allow(clippy::collapsible_if)] // See arti#2342
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#![deny(clippy::unused_async)]
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//! <!-- @@ end lint list maintained by maint/add_warning @@ -->
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use std::time;
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use thiserror::Error;
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pub mod signed;
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pub mod timed;
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/// An error that can occur when checking whether a Timebound object is
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/// currently valid.
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#[derive(Debug, Clone, Error, PartialEq, Eq)]
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#[non_exhaustive]
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pub enum TimeValidityError {
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    /// The object is not yet valid
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    #[error("Object will not be valid for {}", humantime::format_duration(*.0))]
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    NotYetValid(time::Duration),
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    /// The object is expired
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    #[error("Object has been expired for {}", humantime::format_duration(*.0))]
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    Expired(time::Duration),
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    /// The object isn't timely, and we don't know why, or won't say.
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    #[error("Object is not currently valid")]
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    Unspecified,
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}
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/// A Timebound object is one that is only valid for a given range of time.
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///
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/// It's better to wrap things in a TimeBound than to give them an is_valid()
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/// valid method, so that you can make sure that nobody uses the object before
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/// checking it.
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pub trait Timebound<T>: Sized {
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    /// An error type that's returned when the object is _not_ timely.
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    type Error;
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    /// Check whether this object is valid at a given time.
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    ///
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    /// Return Ok if the object is valid, and an error if the object is not.
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    fn is_valid_at(&self, t: &time::SystemTime) -> Result<(), Self::Error>;
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    /// Return the underlying object without checking whether it's valid.
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    fn dangerously_assume_timely(self) -> T;
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    /// Unwrap this Timebound object if it is valid at a given time.
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    fn check_valid_at(self, t: &time::SystemTime) -> Result<T, Self::Error> {
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        self.is_valid_at(t)?;
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        Ok(self.dangerously_assume_timely())
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    }
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    /// Unwrap this Timebound object if it is valid now.
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    fn check_valid_now(self) -> Result<T, Self::Error> {
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        self.check_valid_at(&time::SystemTime::now())
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    }
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    /// Unwrap this object if it is valid at the provided time t.
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    /// If no time is provided, check the object at the current time.
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    fn check_valid_at_opt(self, t: Option<time::SystemTime>) -> Result<T, Self::Error> {
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        match t {
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            Some(when) => self.check_valid_at(&when),
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            None => self.check_valid_now(),
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        }
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    }
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}
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/// A cryptographically signed object that can be validated without
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/// additional public keys.
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///
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/// It's better to wrap things in a SelfSigned than to give them an is_valid()
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/// method, so that you can make sure that nobody uses the object before
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/// checking it.  It's better to wrap things in a SelfSigned than to check
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/// them immediately, since you might want to defer the signature checking
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/// operation to another thread.
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pub trait SelfSigned<T>: Sized {
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    /// An error type that's returned when the object is _not_ well-signed.
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    type Error;
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    /// Check the signature on this object
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    fn is_well_signed(&self) -> Result<(), Self::Error>;
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    /// Return the underlying object without checking its signature.
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    fn dangerously_assume_wellsigned(self) -> T;
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    /// Unwrap this object if the signature is valid
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    fn check_signature(self) -> Result<T, Self::Error> {
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        self.is_well_signed()?;
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        Ok(self.dangerously_assume_wellsigned())
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    }
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}
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/// A cryptographically signed object that needs an external public
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/// key to validate it.
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pub trait ExternallySigned<T>: Sized {
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    /// The type of the public key object.
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    ///
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    /// You can use a tuple or a vector here if the object is signed
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    /// with multiple keys.
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    type Key: ?Sized;
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    /// A type that describes what keys are missing for this object.
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    type KeyHint;
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    /// An error type that's returned when the object is _not_ well-signed.
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    type Error;
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    /// Check whether k is the right key for this object.  If not, return
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    /// an error describing what key would be right.
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    ///
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    /// This function is allowed to return 'true' for a bad key, but never
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    /// 'false' for a good key.
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    fn key_is_correct(&self, k: &Self::Key) -> Result<(), Self::KeyHint>;
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    /// Check the signature on this object
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    fn is_well_signed(&self, k: &Self::Key) -> Result<(), Self::Error>;
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    /// Unwrap this object without checking any signatures on it.
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    fn dangerously_assume_wellsigned(self) -> T;
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    /// Unwrap this object if it's correctly signed by a provided key.
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    fn check_signature(self, k: &Self::Key) -> Result<T, Self::Error> {
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        self.is_well_signed(k)?;
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        Ok(self.dangerously_assume_wellsigned())
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    }
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}