rns_crypto/
hmac.rs

1use hmac::Mac;
2
3#[derive(Clone)]
4pub struct HmacSha256 {
5    inner: hmac::Hmac<sha2::Sha256>,
6}
7
8impl HmacSha256 {
9    pub fn new(key: &[u8]) -> Self {
10        HmacSha256 {
11            inner: hmac::Hmac::<sha2::Sha256>::new_from_slice(key)
12                .expect("HMAC accepts any key length"),
13        }
14    }
15
16    pub fn update(&mut self, data: &[u8]) {
17        self.inner.update(data);
18    }
19
20    pub fn finalize(&self) -> [u8; 32] {
21        self.inner.clone().finalize().into_bytes().into()
22    }
23}
24
25pub fn hmac_sha256(key: &[u8], data: &[u8]) -> [u8; 32] {
26    let mut h = HmacSha256::new(key);
27    h.update(data);
28    h.finalize()
29}
30
31#[cfg(test)]
32mod tests {
33    use super::*;
34
35    fn hex_to_bytes(hex: &str) -> alloc::vec::Vec<u8> {
36        (0..hex.len())
37            .step_by(2)
38            .map(|i| u8::from_str_radix(&hex[i..i + 2], 16).unwrap())
39            .collect()
40    }
41
42    #[test]
43    fn test_hmac_rfc4231_test1() {
44        let key = hex_to_bytes("0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b");
45        let data = b"Hi There";
46        let expected =
47            hex_to_bytes("b0344c61d8db38535ca8afceaf0bf12b881dc200c9833da726e9376c2e32cff7");
48        assert_eq!(hmac_sha256(&key, data).to_vec(), expected);
49    }
50
51    #[test]
52    fn test_hmac_rfc4231_test2() {
53        let key = b"Jefe";
54        let data = b"what do ya want for nothing?";
55        let expected =
56            hex_to_bytes("5bdcc146bf60754e6a042426089575c75a003f089d2739839dec58b964ec3843");
57        assert_eq!(hmac_sha256(key, data).to_vec(), expected);
58    }
59
60    #[test]
61    fn test_hmac_empty_msg() {
62        let key = b"secret";
63        let result = hmac_sha256(key, b"");
64        assert_eq!(result.len(), 32);
65    }
66
67    #[test]
68    fn test_hmac_long_key() {
69        let key = [0xAA; 131];
70        let data = b"Test Using Larger Than Block-Size Key - Hash Key First";
71        let expected =
72            hex_to_bytes("60e431591ee0b67f0d8a26aacbf5b77f8e0bc6213728c5140546040f0ee37f54");
73        assert_eq!(hmac_sha256(&key, data).to_vec(), expected);
74    }
75
76    #[test]
77    fn test_hmac_incremental() {
78        let key = b"key";
79        let data = b"hello world";
80        let expected = hmac_sha256(key, data);
81
82        let mut h = HmacSha256::new(key);
83        h.update(b"hello ");
84        h.update(b"world");
85        assert_eq!(h.finalize(), expected);
86    }
87}
rns_crypto/hmac.rs

rns_crypto/
hmac.rs
