arcana/hash/
sha224.rs

1//! SHA-224 hash function (FIPS 180-4).
2//!
3//! Same as SHA-256 but with different initial values, truncated to
4//! 224 bits (28 bytes). Used in some government profiles and
5//! FIPS-constrained environments.
6
7use super::sha256::Sha256;
8use crate::Hasher;
9
10const H0_224: [u32; 8] = [
11    0xc1059ed8, 0x367cd507, 0x3070dd17, 0xf70e5939, 0xffc00b31, 0x68581511, 0x64f98fa7, 0xbefa4fa4,
12];
13
14/// SHA-224 hasher (FIPS 180-4). 224-bit output, 64-byte blocks.
15///
16/// SHA-224 reuses the SHA-256 compression function with different
17/// IV constants and a truncated output.
18#[derive(Clone)]
19pub struct Sha224 {
20    inner: Sha256,
21}
22
23impl Hasher for Sha224 {
24    const OUTPUT_LEN: usize = 28;
25    const BLOCK_LEN: usize = 64;
26
27    fn new() -> Self {
28        Self {
29            inner: Sha256::new_with_iv(H0_224),
30        }
31    }
32
33    fn update(&mut self, data: &[u8]) {
34        self.inner.update(data);
35    }
36
37    fn finalize(self) -> Vec<u8> {
38        let mut out = vec![0u8; 28];
39        self.finalize_into(&mut out);
40        out
41    }
42
43    fn finalize_into(self, out: &mut [u8]) {
44        let mut full = [0u8; 32];
45        self.inner.finalize_into(&mut full);
46        let len = out.len().min(28);
47        out[..len].copy_from_slice(&full[..len]);
48    }
49}
50
51#[cfg(test)]
52mod tests {
53    use super::*;
54    use crate::Hasher;
55
56    #[test]
57    fn test_sha224_empty() {
58        let digest = Sha224::hash(b"");
59        let expected: [u8; 28] = [
60            0xd1, 0x4a, 0x02, 0x8c, 0x2a, 0x3a, 0x2b, 0xc9, 0x47, 0x61, 0x02, 0xbb, 0x28, 0x82, 0x34, 0xc4, 0x15, 0xa2,
61            0xb0, 0x1f, 0x82, 0x8e, 0xa6, 0x2a, 0xc5, 0xb3, 0xe4, 0x2f,
62        ];
63        assert_eq!(&digest[..], &expected[..]);
64    }
65
66    #[test]
67    fn test_sha224_abc() {
68        let digest = Sha224::hash(b"abc");
69        let expected: [u8; 28] = [
70            0x23, 0x09, 0x7d, 0x22, 0x34, 0x05, 0xd8, 0x22, 0x86, 0x42, 0xa4, 0x77, 0xbd, 0xa2, 0x55, 0xb3, 0x2a, 0xad,
71            0xbc, 0xe4, 0xbd, 0xa0, 0xb3, 0xf7, 0xe3, 0x6c, 0x9d, 0xa7,
72        ];
73        assert_eq!(&digest[..], &expected[..]);
74    }
75}
arcana/hash/sha224.rs

arcana/hash/
sha224.rs
