twizzler_security/keys/
sig.rs

1use core::fmt::Display;
2
3#[cfg(feature = "log")]
4use log::error;
5use p256::ecdsa::Signature as EcdsaSignature;
6
7use crate::{SecurityError, SigningScheme};
8
9const MAX_SIG_SIZE: usize = 128;
10
11#[derive(Copy, Clone, Debug, PartialEq, Eq)]
12pub struct Signature {
13    //TODO: could just replace this as a heapless vec
14    buf: [u8; MAX_SIG_SIZE],
15    pub len: usize,
16    scheme: SigningScheme,
17}
18
19impl Signature {
20    fn as_bytes(&self) -> &[u8] {
21        &self.buf[0..self.len]
22    }
23}
24
25impl Display for Signature {
26    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
27        write!(
28            f,
29            "Signature(scheme: {:?}, len: {}, bytes: ",
30            self.scheme, self.len
31        )?;
32        for byte in &self.buf[0..self.len] {
33            write!(f, "{:02x}", byte)?;
34        }
35        write!(f, ")")
36    }
37}
38
39impl From<EcdsaSignature> for Signature {
40    fn from(value: EcdsaSignature) -> Self {
41        let mut buf = [0_u8; MAX_SIG_SIZE];
42        let binding = value.to_bytes();
43        let slice = binding.as_slice();
44        buf[0..slice.len()].copy_from_slice(slice);
45
46        Self {
47            buf,
48            len: slice.len(),
49            scheme: SigningScheme::Ecdsa,
50        }
51    }
52}
53
54impl TryFrom<&Signature> for EcdsaSignature {
55    type Error = SecurityError;
56    fn try_from(value: &Signature) -> Result<Self, Self::Error> {
57        if value.scheme != SigningScheme::Ecdsa {
58            #[cfg(feature = "log")]
59            error!("Cannot convert Signature to EcdsaSignature due to scheme mismatch. SigningScheme: {:?}", value.scheme);
60            return Err(SecurityError::InvalidScheme);
61        }
62
63        Ok(EcdsaSignature::from_slice(value.as_bytes()).map_err(|_e| {
64            #[cfg(feature = "log")]
65            error!("Failed to construct a EcdsaSignature due to: {:?}", _e);
66            SecurityError::SignatureMismatch
67        })?)
68    }
69}
twizzler_security/keys/sig.rs

twizzler_security/keys/
sig.rs
