1use ed25519_dalek::Verifier;
2
3use crate::Error;
4use crate::Fingerprint;
5use crate::Signature;
6use crate::UntrustedComment;
7use crate::IO;
8use crate::PK_ALGO;
9use crate::VERIFYING_KEY_BYTES_LEN;
10
11pub struct VerifyingKey {
13 pub(crate) verifying_key: ed25519_dalek::VerifyingKey,
14 pub(crate) fingerprint: Fingerprint,
15 pub(crate) comment: Option<String>,
16}
17
18impl VerifyingKey {
19 pub fn verify(&self, message: &[u8], signature: &Signature) -> Result<(), Error> {
21 self.verifying_key
22 .verify(message, &signature.signature)
23 .map_err(|_| Error::Verification)
24 }
25
26 pub fn fingerprint(&self) -> &Fingerprint {
28 &self.fingerprint
29 }
30}
31
32impl IO for VerifyingKey {
33 fn get_comment(&self) -> UntrustedComment {
34 match self.comment.as_ref() {
35 Some(s) => UntrustedComment::String(s),
36 None => UntrustedComment::Fingerprint("public key", self.fingerprint),
37 }
38 }
39
40 fn to_bytes(&self) -> Vec<u8> {
41 let mut bytes = Vec::with_capacity(VERIFYING_KEY_BYTES_LEN);
42 bytes.extend_from_slice(PK_ALGO.as_bytes());
43 bytes.extend_from_slice(&self.fingerprint[..]);
44 bytes.extend_from_slice(self.verifying_key.as_bytes());
45 bytes
46 }
47
48 fn from_bytes(bytes: &[u8], comment: Option<String>) -> Result<Self, Error> {
49 let algo =
50 std::str::from_utf8(bytes.get(..2).ok_or(Error::Format)?).map_err(|_| Error::Format)?;
51 if algo != PK_ALGO {
52 return Err(Error::Algorithm);
53 }
54 const FINGERPRINT_OFFSET: usize = 2;
55 const VERIFYING_KEY_OFFSET: usize = FINGERPRINT_OFFSET + Fingerprint::LEN;
56 let fingerprint: Fingerprint = bytes
57 .get(FINGERPRINT_OFFSET..VERIFYING_KEY_OFFSET)
58 .ok_or(Error::Format)?
59 .try_into()?;
60 let verifying_key: ed25519_dalek::VerifyingKey = bytes
61 .get(VERIFYING_KEY_OFFSET..)
62 .ok_or(Error::Format)?
63 .try_into()
64 .map_err(|_| Error::Format)?;
65 Ok(Self {
66 verifying_key,
67 fingerprint,
68 comment,
69 })
70 }
71}