1
#![cfg_attr(docsrs, feature(doc_cfg))]
2
#![doc = include_str!("../README.md")]
3
// @@ begin lint list maintained by maint/add_warning @@
4
#![allow(renamed_and_removed_lints)] // @@REMOVE_WHEN(ci_arti_stable)
5
#![allow(unknown_lints)] // @@REMOVE_WHEN(ci_arti_nightly)
6
#![warn(missing_docs)]
7
#![warn(noop_method_call)]
8
#![warn(unreachable_pub)]
9
#![warn(clippy::all)]
10
#![deny(clippy::await_holding_lock)]
11
#![deny(clippy::cargo_common_metadata)]
12
#![deny(clippy::cast_lossless)]
13
#![deny(clippy::checked_conversions)]
14
#![warn(clippy::cognitive_complexity)]
15
#![deny(clippy::debug_assert_with_mut_call)]
16
#![deny(clippy::exhaustive_enums)]
17
#![deny(clippy::exhaustive_structs)]
18
#![deny(clippy::expl_impl_clone_on_copy)]
19
#![deny(clippy::fallible_impl_from)]
20
#![deny(clippy::implicit_clone)]
21
#![deny(clippy::large_stack_arrays)]
22
#![warn(clippy::manual_ok_or)]
23
#![deny(clippy::missing_docs_in_private_items)]
24
#![warn(clippy::needless_borrow)]
25
#![warn(clippy::needless_pass_by_value)]
26
#![warn(clippy::option_option)]
27
#![deny(clippy::print_stderr)]
28
#![deny(clippy::print_stdout)]
29
#![warn(clippy::rc_buffer)]
30
#![deny(clippy::ref_option_ref)]
31
#![warn(clippy::semicolon_if_nothing_returned)]
32
#![warn(clippy::trait_duplication_in_bounds)]
33
#![deny(clippy::unchecked_time_subtraction)]
34
#![deny(clippy::unnecessary_wraps)]
35
#![warn(clippy::unseparated_literal_suffix)]
36
#![deny(clippy::unwrap_used)]
37
#![deny(clippy::mod_module_files)]
38
#![allow(clippy::let_unit_value)] // This can reasonably be done for explicitness
39
#![allow(clippy::uninlined_format_args)]
40
#![allow(clippy::significant_drop_in_scrutinee)] // arti/-/merge_requests/588/#note_2812945
41
#![allow(clippy::result_large_err)] // temporary workaround for arti#587
42
#![allow(clippy::needless_raw_string_hashes)] // complained-about code is fine, often best
43
#![allow(clippy::needless_lifetimes)] // See arti#1765
44
#![allow(mismatched_lifetime_syntaxes)] // temporary workaround for arti#2060
45
#![deny(clippy::unused_async)]
46
//! <!-- @@ end lint list maintained by maint/add_warning @@ -->
47

            
48
use std::time;
49
use thiserror::Error;
50

            
51
pub mod signed;
52
pub mod timed;
53

            
54
/// An error that can occur when checking whether a Timebound object is
55
/// currently valid.
56
#[derive(Debug, Clone, Error, PartialEq, Eq)]
57
#[non_exhaustive]
58
pub enum TimeValidityError {
59
    /// The object is not yet valid
60
    #[error("Object will not be valid for {}", humantime::format_duration(*.0))]
61
    NotYetValid(time::Duration),
62
    /// The object is expired
63
    #[error("Object has been expired for {}", humantime::format_duration(*.0))]
64
    Expired(time::Duration),
65
    /// The object isn't timely, and we don't know why, or won't say.
66
    #[error("Object is not currently valid")]
67
    Unspecified,
68
}
69

            
70
/// A Timebound object is one that is only valid for a given range of time.
71
///
72
/// It's better to wrap things in a TimeBound than to give them an is_valid()
73
/// valid method, so that you can make sure that nobody uses the object before
74
/// checking it.
75
pub trait Timebound<T>: Sized {
76
    /// An error type that's returned when the object is _not_ timely.
77
    type Error;
78

            
79
    /// Check whether this object is valid at a given time.
80
    ///
81
    /// Return Ok if the object is valid, and an error if the object is not.
82
    fn is_valid_at(&self, t: &time::SystemTime) -> Result<(), Self::Error>;
83

            
84
    /// Return the underlying object without checking whether it's valid.
85
    fn dangerously_assume_timely(self) -> T;
86

            
87
    /// Unwrap this Timebound object if it is valid at a given time.
88
666
    fn check_valid_at(self, t: &time::SystemTime) -> Result<T, Self::Error> {
89
666
        self.is_valid_at(t)?;
90
658
        Ok(self.dangerously_assume_timely())
91
666
    }
92

            
93
    /// Unwrap this Timebound object if it is valid now.
94
8
    fn check_valid_now(self) -> Result<T, Self::Error> {
95
8
        self.check_valid_at(&time::SystemTime::now())
96
8
    }
97

            
98
    /// Unwrap this object if it is valid at the provided time t.
99
    /// If no time is provided, check the object at the current time.
100
6
    fn check_valid_at_opt(self, t: Option<time::SystemTime>) -> Result<T, Self::Error> {
101
6
        match t {
102
2
            Some(when) => self.check_valid_at(&when),
103
4
            None => self.check_valid_now(),
104
        }
105
6
    }
106
}
107

            
108
/// A cryptographically signed object that can be validated without
109
/// additional public keys.
110
///
111
/// It's better to wrap things in a SelfSigned than to give them an is_valid()
112
/// method, so that you can make sure that nobody uses the object before
113
/// checking it.  It's better to wrap things in a SelfSigned than to check
114
/// them immediately, since you might want to defer the signature checking
115
/// operation to another thread.
116
pub trait SelfSigned<T>: Sized {
117
    /// An error type that's returned when the object is _not_ well-signed.
118
    type Error;
119
    /// Check the signature on this object
120
    fn is_well_signed(&self) -> Result<(), Self::Error>;
121
    /// Return the underlying object without checking its signature.
122
    fn dangerously_assume_wellsigned(self) -> T;
123

            
124
    /// Unwrap this object if the signature is valid
125
834
    fn check_signature(self) -> Result<T, Self::Error> {
126
834
        self.is_well_signed()?;
127
824
        Ok(self.dangerously_assume_wellsigned())
128
834
    }
129
}
130

            
131
/// A cryptographically signed object that needs an external public
132
/// key to validate it.
133
pub trait ExternallySigned<T>: Sized {
134
    /// The type of the public key object.
135
    ///
136
    /// You can use a tuple or a vector here if the object is signed
137
    /// with multiple keys.
138
    type Key: ?Sized;
139

            
140
    /// A type that describes what keys are missing for this object.
141
    type KeyHint;
142

            
143
    /// An error type that's returned when the object is _not_ well-signed.
144
    type Error;
145

            
146
    /// Check whether k is the right key for this object.  If not, return
147
    /// an error describing what key would be right.
148
    ///
149
    /// This function is allowed to return 'true' for a bad key, but never
150
    /// 'false' for a good key.
151
    fn key_is_correct(&self, k: &Self::Key) -> Result<(), Self::KeyHint>;
152

            
153
    /// Check the signature on this object
154
    fn is_well_signed(&self, k: &Self::Key) -> Result<(), Self::Error>;
155

            
156
    /// Unwrap this object without checking any signatures on it.
157
    fn dangerously_assume_wellsigned(self) -> T;
158

            
159
    /// Unwrap this object if it's correctly signed by a provided key.
160
18
    fn check_signature(self, k: &Self::Key) -> Result<T, Self::Error> {
161
18
        self.is_well_signed(k)?;
162
16
        Ok(self.dangerously_assume_wellsigned())
163
18
    }
164
}