crylib 0.2.0

a collection of cryptographic functions
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

/// The Hash-based Message Authentication Code algorithm.
///
/// HMAC was designed by Mihir Bellare, Ran Canetti, and Hugo Krawczyk.
use crate::hash::{BlockHasher, BufHasher};

pub struct Hmac<const H_LEN: usize, const B_LEN: usize, H>
where
    H: BlockHasher<H_LEN, B_LEN>,
{
    state: H,
    opad: [u8; B_LEN],
}

impl<const H_LEN: usize, const B_LEN: usize, H> Hmac<H_LEN, B_LEN, H>
where
    H: BlockHasher<H_LEN, B_LEN>,
{
    pub fn new(key: &[u8]) -> Self {
        let mut ipad = [0x36; B_LEN];
        let mut opad = [0x5c; B_LEN];
        for ((ipad_byte, opad_byte), key_byte) in ipad.iter_mut().zip(opad.iter_mut()).zip(key) {
            *ipad_byte ^= key_byte;
            *opad_byte ^= key_byte;
        }

        let mut state = H::new();
        state.update(&ipad);
        Self { state, opad }
    }

    pub fn update(&mut self, block: &[u8; B_LEN]) {
        self.state.update(block);
    }

    pub fn finish_with(self, msg: &[u8]) -> [u8; H_LEN] {
        let inner_hash = self.state.finish_with(msg);
        outer_finish::<H_LEN, B_LEN, H>(&self.opad, &inner_hash)
    }

    pub fn finish(self) -> [u8; H_LEN] {
        let inner_hash = self.state.finish();
        outer_finish::<H_LEN, B_LEN, H>(&self.opad, &inner_hash)
    }

    pub fn auth(key: &[u8], msg: &[u8]) -> [u8; H_LEN] {
        let state = Self::new(key);
        state.finish_with(msg)
    }
}

impl<const H_LEN: usize, const B_LEN: usize, H> Hmac<H_LEN, B_LEN, BufHasher<H_LEN, B_LEN, H>>
where
    H: BlockHasher<H_LEN, B_LEN>,
{
    pub fn update_with(&mut self, msg: &[u8]) {
        self.state.update_with(msg)
    }
}

fn outer_finish<const H_LEN: usize, const B_LEN: usize, H>(
    opad: &[u8; B_LEN],
    inner_hash: &[u8; H_LEN],
) -> [u8; H_LEN]
where
    H: BlockHasher<H_LEN, B_LEN>,
{
    let mut hasher = H::new();
    hasher.update(opad);
    hasher.finish_with(inner_hash)
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::hash::{Sha256, Sha512};
    // test vectors from https://datatracker.ietf.org/doc/html/rfc4231

    #[test]
    fn hmac() {
        let key = [
            0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
            0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
        ];
        let msg = [0x48, 0x69, 0x20, 0x54, 0x68, 0x65, 0x72, 0x65];
        let mac_sha256 = [
            0xb0, 0x34, 0x4c, 0x61, 0xd8, 0xdb, 0x38, 0x53, 0x5c, 0xa8, 0xaf, 0xce, 0xaf, 0x0b,
            0xf1, 0x2b, 0x88, 0x1d, 0xc2, 0x00, 0xc9, 0x83, 0x3d, 0xa7, 0x26, 0xe9, 0x37, 0x6c,
            0x2e, 0x32, 0xcf, 0xf7,
        ];
        assert_eq!(
            Hmac::<{ Sha256::HASH_SIZE }, { Sha256::BLOCK_SIZE }, Sha256>::auth(&key, &msg),
            mac_sha256
        );
        let mac_sha512 = [
            0x87, 0xaa, 0x7c, 0xde, 0xa5, 0xef, 0x61, 0x9d, 0x4f, 0xf0, 0xb4, 0x24, 0x1a, 0x1d,
            0x6c, 0xb0, 0x23, 0x79, 0xf4, 0xe2, 0xce, 0x4e, 0xc2, 0x78, 0x7a, 0xd0, 0xb3, 0x05,
            0x45, 0xe1, 0x7c, 0xde, 0xda, 0xa8, 0x33, 0xb7, 0xd6, 0xb8, 0xa7, 0x02, 0x03, 0x8b,
            0x27, 0x4e, 0xae, 0xa3, 0xf4, 0xe4, 0xbe, 0x9d, 0x91, 0x4e, 0xeb, 0x61, 0xf1, 0x70,
            0x2e, 0x69, 0x6c, 0x20, 0x3a, 0x12, 0x68, 0x54,
        ];
        assert_eq!(
            Hmac::<{ Sha512::HASH_SIZE }, { Sha512::BLOCK_SIZE }, Sha512>::auth(&key, &msg),
            mac_sha512
        );

        let msg = [
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
        ];
        let key = [
            0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
            0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        ];
        let mac_sha256 = [
            0x77, 0x3e, 0xa9, 0x1e, 0x36, 0x80, 0x0e, 0x46, 0x85, 0x4d, 0xb8, 0xeb, 0xd0, 0x91,
            0x81, 0xa7, 0x29, 0x59, 0x09, 0x8b, 0x3e, 0xf8, 0xc1, 0x22, 0xd9, 0x63, 0x55, 0x14,
            0xce, 0xd5, 0x65, 0xfe,
        ];
        assert_eq!(
            Hmac::<{ Sha256::HASH_SIZE }, { Sha256::BLOCK_SIZE }, Sha256>::auth(&key, &msg),
            mac_sha256
        );
        let mac_sha512 = [
            0xfa, 0x73, 0xb0, 0x08, 0x9d, 0x56, 0xa2, 0x84, 0xef, 0xb0, 0xf0, 0x75, 0x6c, 0x89,
            0x0b, 0xe9, 0xb1, 0xb5, 0xdb, 0xdd, 0x8e, 0xe8, 0x1a, 0x36, 0x55, 0xf8, 0x3e, 0x33,
            0xb2, 0x27, 0x9d, 0x39, 0xbf, 0x3e, 0x84, 0x82, 0x79, 0xa7, 0x22, 0xc8, 0x06, 0xb4,
            0x85, 0xa4, 0x7e, 0x67, 0xc8, 0x07, 0xb9, 0x46, 0xa3, 0x37, 0xbe, 0xe8, 0x94, 0x26,
            0x74, 0x27, 0x88, 0x59, 0xe1, 0x32, 0x92, 0xfb,
        ];
        assert_eq!(
            Hmac::<{ Sha512::HASH_SIZE }, { Sha512::BLOCK_SIZE }, Sha512>::auth(&key, &msg),
            mac_sha512
        );
    }

    #[test]
    fn update_with() {
        let msg = [
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
            0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd, 0xdd,
        ];
        let key = [
            0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
            0xaa, 0xaa, 0xaa, 0xaa, 0xaa, 0xaa,
        ];
        let mac_sha256 = [
            0x77, 0x3e, 0xa9, 0x1e, 0x36, 0x80, 0x0e, 0x46, 0x85, 0x4d, 0xb8, 0xeb, 0xd0, 0x91,
            0x81, 0xa7, 0x29, 0x59, 0x09, 0x8b, 0x3e, 0xf8, 0xc1, 0x22, 0xd9, 0x63, 0x55, 0x14,
            0xce, 0xd5, 0x65, 0xfe,
        ];
        let mut hmac = Hmac::<
            { Sha256::HASH_SIZE },
            { Sha256::BLOCK_SIZE },
            BufHasher<{ Sha256::HASH_SIZE }, { Sha256::BLOCK_SIZE }, Sha256>,
        >::new(&key);
        for block in msg.chunks(3) {
            hmac.update_with(block);
        }
        let mac = hmac.finish();
        assert_eq!(mac, mac_sha256);
        let mac_sha512 = [
            0xfa, 0x73, 0xb0, 0x08, 0x9d, 0x56, 0xa2, 0x84, 0xef, 0xb0, 0xf0, 0x75, 0x6c, 0x89,
            0x0b, 0xe9, 0xb1, 0xb5, 0xdb, 0xdd, 0x8e, 0xe8, 0x1a, 0x36, 0x55, 0xf8, 0x3e, 0x33,
            0xb2, 0x27, 0x9d, 0x39, 0xbf, 0x3e, 0x84, 0x82, 0x79, 0xa7, 0x22, 0xc8, 0x06, 0xb4,
            0x85, 0xa4, 0x7e, 0x67, 0xc8, 0x07, 0xb9, 0x46, 0xa3, 0x37, 0xbe, 0xe8, 0x94, 0x26,
            0x74, 0x27, 0x88, 0x59, 0xe1, 0x32, 0x92, 0xfb,
        ];
        let mut hmac = Hmac::<
            { Sha512::HASH_SIZE },
            { Sha512::BLOCK_SIZE },
            BufHasher<{ Sha512::HASH_SIZE }, { Sha512::BLOCK_SIZE }, Sha512>,
        >::new(&key);
        for block in msg.chunks(3) {
            hmac.update_with(block);
        }
        let mac = hmac.finish();
        assert_eq!(mac, mac_sha512);
        assert_eq!(mac, mac_sha512);
    }
}