open_envault/crypto/
util.rs

1//! Small time helpers: SOPS metadata timestamps are RFC 3339, second
2//! precision, UTC (`time.RFC3339` in Go).
3
4use std::time::{SystemTime, UNIX_EPOCH};
5
6/// Seconds since the Unix epoch.
7fn unix_seconds() -> i64 {
8    SystemTime::now()
9        .duration_since(UNIX_EPOCH)
10        .map(|d| d.as_secs() as i64)
11        .unwrap_or(0)
12}
13
14/// Civil (year, month, day) from days since the Unix epoch.
15fn civil_from_days(z: i64) -> (i64, u32, u32) {
16    let z = z + 719_468;
17    let era = if z >= 0 { z } else { z - 146_096 } / 146_097;
18    let doe = (z - era * 146_097) as u64;
19    let yoe = (doe - doe / 1460 + doe / 36_524 - doe / 146_096) / 365;
20    let y = yoe as i64 + era * 400;
21    let doy = doe - (365 * yoe + yoe / 4 - yoe / 100);
22    let mp = (5 * doy + 2) / 153;
23    let d = (doy - (153 * mp + 2) / 5 + 1) as u32;
24    let m = if mp < 10 { mp + 3 } else { mp - 9 } as u32;
25    (if m <= 2 { y + 1 } else { y }, m, d)
26}
27
28fn pad2(n: i64) -> String {
29    if n < 10 {
30        format!("0{n}")
31    } else {
32        n.to_string()
33    }
34}
35
36/// Current UTC time as `YYYY-MM-DDTHH:MM:SSZ` (SOPS `time.RFC3339`).
37pub fn rfc3339_now() -> String {
38    let secs = unix_seconds();
39    let days = secs.div_euclid(86_400);
40    let rem = secs.rem_euclid(86_400);
41    let (h, m, s) = (rem / 3600, (rem % 3600) / 60, rem % 60);
42    let (y, mo, d) = civil_from_days(days);
43    format!(
44        "{:04}-{}-{}T{}:{}:{}Z",
45        y,
46        pad2(mo as i64),
47        pad2(d as i64),
48        pad2(h),
49        pad2(m),
50        pad2(s)
51    )
52}
53
54/// Current UTC date as `YYYY-MM-DD` (for generated key headers).
55pub fn date_utc_today() -> String {
56    let days = unix_seconds().div_euclid(86_400);
57    let (y, mo, d) = civil_from_days(days);
58    format!("{:04}-{:02}-{:02}", y, mo, d)
59}
60
61#[cfg(test)]
62mod tests {
63    use super::*;
64
65    #[test]
66    fn timestamp_shape() {
67        let s = rfc3339_now();
68        assert_eq!(s.len(), 20, "{s}");
69        assert!(s.ends_with('Z'));
70        assert_eq!(&s[4..5], "-");
71        assert_eq!(&s[10..11], "T");
72    }
73}
open_envault/crypto/util.rs

open_envault/crypto/
util.rs
