latchkey 0.4.0

Sans-IO sign-in building blocks and policy: Argon2id passwords, TOTP, recovery codes, passkeys, tokens, sealing, cookies, lockout, rate limits and sign-in flows as pure state machines
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253

//! The app's settings take effect: non-default code sizes, attempt budgets, lifetimes and
//! TOTP parameters, driven through the flows by the in-memory app.
#![allow(
    clippy::unwrap_used,
    clippy::expect_used,
    clippy::panic,
    clippy::indexing_slicing
)]

mod common;

use common::{App, Browser, ORIGIN, OWNER, PASSWORD, cheap, code_of};
use latchkey::error::InvalidRequestReason;
use latchkey::flow::email_link::EmailLink;
use latchkey::flow::sign_in::SignIn;
use latchkey::flow::{self, LinkKind};
use latchkey::totp;
use latchkey::{Config, ConfigBuilder, Error};
use time::Duration;

fn builder() -> ConfigBuilder {
    Config::builder(OWNER, ORIGIN).password_params(cheap())
}

#[test]
fn an_eight_digit_email_code_with_three_attempts_and_a_two_minute_link() {
    let mut app = App::with_config(
        builder()
            .email_code_digits(8)
            .email_code_attempts(3)
            .link_ttl(Duration::minutes(2)),
    );
    let mut browser = Browser::default();
    app.setup_owner(&mut browser);
    app.advance(Duration::minutes(2));
    let mut tv = Browser::default();
    app.request_email_link(&mut tv, OWNER);
    let mail = app.mail.last().unwrap().clone();
    let code = mail.code.as_ref().unwrap().expose_secret().to_owned();
    assert_eq!(code.len(), 8);
    assert!(code.bytes().all(|b| b.is_ascii_digit()));
    assert!(mail.text().contains(&code));
    let two = Some(app.now + Duration::minutes(2));
    assert_eq!(mail.expires_at, two);
    assert!(
        app.email_codes
            .values()
            .all(|request| Some(request.expires_at) == two)
    );

    // Three wrong guesses (one of them only 6 digits long) end the request and its link.
    let wrong = if code == "00000000" {
        "00000001"
    } else {
        "00000000"
    };
    for (attempt, guess) in [&code[..6], wrong, wrong].into_iter().enumerate() {
        assert_eq!(
            app.redeem_email_code(&mut tv, guess).err(),
            Some(Error::SignInFailed)
        );
        assert_eq!(app.email_codes.len(), usize::from(attempt < 2), "{attempt}");
    }
    assert_eq!(
        app.redeem_email_code(&mut tv, &code).err(),
        Some(Error::SignInFailed),
        "the request is dead"
    );
    assert_eq!(
        app.redeem_email_link(&mut Browser::default(), &mail.link_token().unwrap())
            .err(),
        Some(Error::SignInFailed),
        "and so is its link"
    );
}

#[test]
fn a_two_minute_link_and_its_code_expire_after_two_minutes() {
    let mut app = App::with_config(builder().link_ttl(Duration::minutes(2)));
    let mut browser = Browser::default();
    app.setup_owner(&mut browser);
    app.advance(Duration::minutes(2));

    let mut tv = Browser::default();
    app.request_email_link(&mut tv, OWNER);
    let code = app.mail.last().unwrap().code.clone().unwrap();
    app.advance(Duration::minutes(2) - Duration::seconds(1));
    assert!(matches!(
        app.redeem_email_code(&mut tv, code.expose_secret()),
        Ok(EmailLink::SecondFactor { .. })
    ));

    app.advance(Duration::minutes(2));
    let mut phone = Browser::default();
    app.request_email_link(&mut phone, OWNER);
    let mail = app.mail.last().unwrap().clone();
    app.advance(Duration::minutes(2));
    assert_eq!(
        app.redeem_email_code(&mut phone, mail.code.as_ref().unwrap().expose_secret())
            .err(),
        Some(Error::SignInFailed)
    );
    assert_eq!(
        app.redeem_email_link(&mut phone, &mail.link_token().unwrap())
            .err(),
        Some(Error::SignInFailed)
    );
}

#[test]
fn eight_digit_totp_with_a_sixty_second_step() {
    let mut app = App::with_config(builder().totp_digits(8).totp_step(60));
    let params = app.config.totp_params();
    assert_eq!((params.digits(), params.step_secs()), (8, 60));
    let mut browser = Browser::default();
    let (secret, _) = app.setup_owner(&mut browser);

    let enrolment = totp::enrolment(&secret, "Home", OWNER, params).unwrap();
    assert!(enrolment.otpauth_url.contains("digits=8"));
    assert!(enrolment.otpauth_url.contains("period=60"));

    app.advance(Duration::seconds(60));
    let mut laptop = Browser::default();
    app.password_step(&mut laptop, OWNER, PASSWORD).unwrap();
    // A 6-digit code from an authenticator still on the defaults is not a TOTP code here.
    let six = secret
        .code_at(app.now, totp::TotpParams::default())
        .unwrap();
    assert_eq!(
        app.code_step(&mut laptop, &six).err(),
        Some(Error::SignInFailed)
    );
    let eight = secret.code_at(app.now, params).unwrap();
    assert_eq!(eight.len(), 8);
    assert!(matches!(
        app.code_step(&mut laptop, &eight),
        Ok(SignIn::SignedIn { .. })
    ));
    let step = app.rows[&app.owner_id()].last_step.unwrap();
    let unix = u64::try_from(app.now.unix_timestamp()).unwrap();
    assert_eq!(step.get(), unix / 60, "steps count 60-second periods");
}

#[test]
fn sixteen_recovery_codes_at_setup_and_when_regenerated() {
    let mut app = App::with_config(builder().recovery_code_count(16));
    let mut browser = Browser::default();
    let (_, codes) = app.setup_owner(&mut browser);
    assert_eq!(codes.len(), 16);
    assert_eq!(app.rows[&app.owner_id()].recovery.len(), 16);

    let client = app.client(&browser, None);
    let step = flow::regenerate_recovery_codes(
        &app.config,
        app.owner_id(),
        &client,
        app.now,
        &mut app.rng,
    );
    assert_eq!(step.state.len(), 16);
    let new = step.state;
    app.apply(step.effects, &mut browser).unwrap();
    let mut laptop = Browser::default();
    app.password_step(&mut laptop, OWNER, PASSWORD).unwrap();
    assert!(app.code_step(&mut laptop, &code_of(&new, 15)).is_ok());
}

#[test]
fn a_longer_minimum_password_is_enforced() {
    // PASSWORD has 28 characters.
    let mut app = App::with_config(builder().password_min_len(30));
    let mut browser = Browser::default();
    app.request_setup(&mut browser);
    let token = app.mail.last().unwrap().link_token().unwrap();
    app.redeem_setup(&mut browser, LinkKind::Setup, &token)
        .unwrap();
    assert_eq!(
        app.setup_password(&mut browser, PASSWORD).err(),
        Some(Error::InvalidRequest(
            InvalidRequestReason::PasswordTooShort
        ))
    );
    assert!(
        app.setup_password(&mut browser, "correct horse battery staple again")
            .is_ok()
    );
}

#[test]
fn out_of_range_settings_are_refused() {
    use latchkey::error::ConfigReason;
    let refused = |builder: ConfigBuilder, reason| {
        assert_eq!(builder.build().err(), Some(Error::Config(reason)));
    };
    refused(
        builder().email_code_digits(5),
        ConfigReason::EmailCodeDigits,
    );
    refused(
        builder().email_code_digits(11),
        ConfigReason::EmailCodeDigits,
    );
    refused(
        builder().email_code_attempts(0),
        ConfigReason::EmailCodeAttempts,
    );
    refused(
        builder().email_code_attempts(21),
        ConfigReason::EmailCodeAttempts,
    );
    refused(
        builder().recovery_code_count(3),
        ConfigReason::RecoveryCodeCount,
    );
    refused(
        builder().recovery_code_count(33),
        ConfigReason::RecoveryCodeCount,
    );
    refused(builder().totp_digits(7), ConfigReason::TotpDigits);
    refused(builder().totp_step(10), ConfigReason::TotpStep);
    refused(builder().totp_step(121), ConfigReason::TotpStep);
    refused(builder().totp_skew(4), ConfigReason::TotpSkew);
    refused(builder().password_min_len(7), ConfigReason::PasswordLength);
    refused(
        builder().password_max_len(2000),
        ConfigReason::PasswordLength,
    );
    refused(
        builder().password_min_len(100).password_max_len(64),
        ConfigReason::PasswordLength,
    );
    refused(
        builder().display_name_max_len(0),
        ConfigReason::DisplayNameLength,
    );
    refused(
        builder().display_name_max_len(1001),
        ConfigReason::DisplayNameLength,
    );
    // The edges are allowed.
    for ok in [
        builder().email_code_digits(10).email_code_attempts(20),
        builder().email_code_digits(6).email_code_attempts(1),
        builder().recovery_code_count(4),
        builder().recovery_code_count(32),
        builder().totp_digits(8).totp_step(15).totp_skew(0),
        builder().totp_step(120).totp_skew(3),
        builder().password_min_len(8).password_max_len(64),
        builder().display_name_max_len(1),
    ] {
        assert!(ok.build().is_ok());
    }
}