ssh_key/public/
ed25519.rs

1//! Ed25519 public keys.
2//!
3//! Edwards Digital Signature Algorithm (EdDSA) over Curve25519.
4
5use crate::{Error, Result};
6use core::fmt;
7use encoding::{CheckedSum, Decode, Encode, Reader, Writer};
8
9/// Ed25519 public key.
10///
11/// Encodings for Ed25519 public keys are described in [RFC8709 § 4]:
12///
13/// > The "ssh-ed25519" key format has the following encoding:
14/// >
15/// > **string** "ssh-ed25519"
16/// >
17/// > **string** key
18/// >
19/// > Here, 'key' is the 32-octet public key described in RFC8032
20///
21/// [RFC8709 § 4]: https://datatracker.ietf.org/doc/html/rfc8709#section-4
22#[derive(Copy, Clone, Debug, Eq, Hash, PartialEq, PartialOrd, Ord)]
23pub struct Ed25519PublicKey(pub [u8; Self::BYTE_SIZE]);
24
25impl Ed25519PublicKey {
26    /// Size of an Ed25519 public key in bytes.
27    pub const BYTE_SIZE: usize = 32;
28}
29
30impl AsRef<[u8; Self::BYTE_SIZE]> for Ed25519PublicKey {
31    fn as_ref(&self) -> &[u8; Self::BYTE_SIZE] {
32        &self.0
33    }
34}
35
36impl Decode for Ed25519PublicKey {
37    type Error = Error;
38
39    fn decode(reader: &mut impl Reader) -> Result<Self> {
40        let mut bytes = [0u8; Self::BYTE_SIZE];
41        reader.read_prefixed(|reader| reader.read(&mut bytes))?;
42        Ok(Self(bytes))
43    }
44}
45
46impl Encode for Ed25519PublicKey {
47    fn encoded_len(&self) -> encoding::Result<usize> {
48        [4, Self::BYTE_SIZE].checked_sum()
49    }
50
51    fn encode(&self, writer: &mut impl Writer) -> encoding::Result<()> {
52        self.0.as_slice().encode(writer)?;
53        Ok(())
54    }
55}
56
57impl TryFrom<&[u8]> for Ed25519PublicKey {
58    type Error = Error;
59
60    fn try_from(bytes: &[u8]) -> Result<Self> {
61        Ok(Self(bytes.try_into()?))
62    }
63}
64
65impl fmt::Display for Ed25519PublicKey {
66    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
67        write!(f, "{self:X}")
68    }
69}
70
71impl fmt::LowerHex for Ed25519PublicKey {
72    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
73        for byte in self.as_ref() {
74            write!(f, "{byte:02x}")?;
75        }
76        Ok(())
77    }
78}
79
80impl fmt::UpperHex for Ed25519PublicKey {
81    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
82        for byte in self.as_ref() {
83            write!(f, "{byte:02X}")?;
84        }
85        Ok(())
86    }
87}
88
89#[cfg(feature = "ed25519")]
90impl TryFrom<Ed25519PublicKey> for ed25519_dalek::VerifyingKey {
91    type Error = Error;
92
93    fn try_from(key: Ed25519PublicKey) -> Result<ed25519_dalek::VerifyingKey> {
94        ed25519_dalek::VerifyingKey::try_from(&key)
95    }
96}
97
98#[cfg(feature = "ed25519")]
99impl TryFrom<&Ed25519PublicKey> for ed25519_dalek::VerifyingKey {
100    type Error = Error;
101
102    fn try_from(key: &Ed25519PublicKey) -> Result<ed25519_dalek::VerifyingKey> {
103        ed25519_dalek::VerifyingKey::from_bytes(key.as_ref()).map_err(|_| Error::Crypto)
104    }
105}
106
107#[cfg(feature = "ed25519")]
108impl From<ed25519_dalek::VerifyingKey> for Ed25519PublicKey {
109    fn from(key: ed25519_dalek::VerifyingKey) -> Ed25519PublicKey {
110        Ed25519PublicKey::from(&key)
111    }
112}
113
114#[cfg(feature = "ed25519")]
115impl From<&ed25519_dalek::VerifyingKey> for Ed25519PublicKey {
116    fn from(key: &ed25519_dalek::VerifyingKey) -> Ed25519PublicKey {
117        Ed25519PublicKey(key.to_bytes())
118    }
119}
ssh_key/public/ed25519.rs

ssh_key/public/
ed25519.rs
