examples-features/ctap: Add support for sign and attest
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
diff --git a/examples-features/ctap.rs b/examples-features/ctap.rs
index 176c5c5..f0eb32c 100644
--- a/examples-features/ctap.rs
+++ b/examples-features/ctap.rs
@@ -22,6 +22,7 @@
use libtock::println;
use libtock::result::TockResult;
use libtock::syscalls;
+use p256::ecdsa::{signature::Signer, SigningKey};
use p256::elliptic_curve::ff::PrimeField;
use p256::{Scalar, SecretKey};
use subtle::{Choice, ConditionallySelectable};
@@ -311,18 +312,47 @@
fn attest(
&mut self,
- _id: &Self::CredentialId,
- _data: &[u8],
+ id: &Self::CredentialId,
+ data: &[u8],
) -> Option<Signature<Self::SignatureBuffer>> {
- unimplemented!();
+ // TODO: Should attest be different then sign?
+ let attest = {
+ let secret_key = SecretKey::from_bytes(id.get_mac()).unwrap();
+
+ let signer = SigningKey::from(&secret_key);
+
+ let sig = signer.sign(data);
+
+ let mut r: [u8; 32] = [0; 32];
+ r.clone_from_slice(&sig.r().as_ref().to_bytes());
+ let mut s: [u8; 32] = [0; 32];
+ s.clone_from_slice(&sig.s().as_ref().to_bytes());
+
+ Signature::nistp256(r, s)
+ };
+
+ Some(attest)
}
fn sign(
&mut self,
- _id: &Self::CredentialId,
- _data: &[u8],
+ id: &Self::CredentialId,
+ data: &[u8],
) -> Option<Signature<Self::SignatureBuffer>> {
- unimplemented!();
+ let attest = {
+ let secret_key = SecretKey::from_bytes(id.get_mac()).unwrap();
+ let signer = SigningKey::from(&secret_key);
+ let sig = signer.sign(data);
+
+ let mut r: [u8; 32] = [0; 32];
+ r.clone_from_slice(&sig.r().as_ref().to_bytes());
+ let mut s: [u8; 32] = [0; 32];
+ s.clone_from_slice(&sig.s().as_ref().to_bytes());
+
+ Signature::nistp256(r, s)
+ };
+
+ Some(attest)
}
fn start_timeout(&mut self) {
