pq-mayo 0.4.0

MAYO post-quantum signature scheme
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

// SPDX-License-Identifier: Apache-2.0 OR MIT

//! MAYO verifying (public) key.

use crate::error::Error;
use crate::mayo_signature::Signature;
use crate::params::MayoParameter;
use crate::signing_key::SigningKey;
use crate::verify::mayo_verify;
use core::marker::PhantomData;

/// A MAYO verifying key (compact public key).
#[derive(Clone)]
pub struct VerifyingKey<P: MayoParameter> {
    pub(crate) bytes: Vec<u8>,
    pub(crate) _marker: PhantomData<P>,
}

impl<P: MayoParameter> AsRef<[u8]> for VerifyingKey<P> {
    fn as_ref(&self) -> &[u8] {
        &self.bytes
    }
}

impl<P: MayoParameter> TryFrom<&[u8]> for VerifyingKey<P> {
    type Error = Error;

    fn try_from(bytes: &[u8]) -> Result<Self, Self::Error> {
        if bytes.len() != P::CPK_BYTES {
            return Err(Error::InvalidKeyLength {
                expected: P::CPK_BYTES,
                got: bytes.len(),
            });
        }
        Ok(Self {
            bytes: bytes.to_vec(),
            _marker: PhantomData,
        })
    }
}

impl<P: MayoParameter> TryFrom<Vec<u8>> for VerifyingKey<P> {
    type Error = Error;

    fn try_from(bytes: Vec<u8>) -> Result<Self, Self::Error> {
        if bytes.len() != P::CPK_BYTES {
            return Err(Error::InvalidKeyLength {
                expected: P::CPK_BYTES,
                got: bytes.len(),
            });
        }
        Ok(Self {
            bytes,
            _marker: PhantomData,
        })
    }
}

impl<P: MayoParameter> TryFrom<&Vec<u8>> for VerifyingKey<P> {
    type Error = Error;

    fn try_from(bytes: &Vec<u8>) -> Result<Self, Self::Error> {
        Self::try_from(bytes.as_slice())
    }
}

impl<P: MayoParameter> TryFrom<Box<[u8]>> for VerifyingKey<P> {
    type Error = Error;

    fn try_from(bytes: Box<[u8]>) -> Result<Self, Self::Error> {
        if bytes.len() != P::CPK_BYTES {
            return Err(Error::InvalidKeyLength {
                expected: P::CPK_BYTES,
                got: bytes.len(),
            });
        }
        Ok(Self {
            bytes: bytes.into_vec(),
            _marker: PhantomData,
        })
    }
}

impl<P: MayoParameter> PartialEq for VerifyingKey<P> {
    fn eq(&self, other: &Self) -> bool {
        self.bytes == other.bytes
    }
}

impl<P: MayoParameter> Eq for VerifyingKey<P> {}

impl<P: MayoParameter> core::fmt::Debug for VerifyingKey<P> {
    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
        f.debug_struct("VerifyingKey")
            .field("variant", &P::NAME)
            .field("bytes", &hex::encode(&self.bytes))
            .finish()
    }
}

impl<P: MayoParameter> From<&SigningKey<P>> for VerifyingKey<P> {
    fn from(sk: &SigningKey<P>) -> Self {
        Self {
            bytes: sk.cpk.clone(),
            _marker: PhantomData,
        }
    }
}

impl<P: MayoParameter> signature::Verifier<Signature<P>> for VerifyingKey<P> {
    fn verify(&self, msg: &[u8], signature: &Signature<P>) -> Result<(), signature::Error> {
        mayo_verify::<P>(msg, signature.as_ref(), &self.bytes).map_err(Into::into)
    }
}

#[cfg(feature = "serde")]
impl<P: MayoParameter> serde::Serialize for VerifyingKey<P> {
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer,
    {
        serdect::slice::serialize_hex_lower_or_bin(&self.bytes, serializer)
    }
}

#[cfg(feature = "serde")]
impl<'de, P: MayoParameter> serde::Deserialize<'de> for VerifyingKey<P> {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        let bytes = serdect::slice::deserialize_hex_or_bin_vec(deserializer)?;
        Self::try_from(bytes).map_err(serde::de::Error::custom)
    }
}