add Display impl for SignatureNoiseMessage and update related error handling

Author: lucasbalieiro

sv2/codec-sv2/src/error.rs

@@ -78,7 +78,14 @@ impl fmt::Display for Error {
             ),
             MissingBytes(u) => write!(f, "Missing `{u}` Noise bytes"),
             #[cfg(feature = "noise_sv2")]
-            NoiseSv2Error(e) => write!(f, "Noise SV2 Error: `{e:?}`"),
+            NoiseSv2Error(e) => match e {
+                NoiseError::InvalidCertificate(msg) => {
+                    write!(f, "Invalid Certificate: {}", msg)
+                }
+                other => {
+                    write!(f, "Noise SV2 Error: {:?}", other)
+                }
+            },
             #[cfg(feature = "noise_sv2")]
             NotInHandShakeState => write!(
                 f,

sv2/noise-sv2/src/error.rs

@@ -6,6 +6,8 @@ use alloc::vec::Vec;
 
 use aes_gcm::Error as AesGcm;
 
+use crate::signature_message::SignatureNoiseMessage;
+
 /// Noise protocol error handling.
 #[derive(Debug, PartialEq, Eq)]
 pub enum Error {
@@ -31,7 +33,7 @@ pub enum Error {
     InvalidCipherState,
 
     /// Provided certificate is invalid or cannot be verified.
-    InvalidCertificate([u8; 74]),
+    InvalidCertificate(SignatureNoiseMessage),
 
     /// A raw public key is invalid or cannot be parsed.
     InvalidRawPublicKey,

sv2/noise-sv2/src/initiator.rs

@@ -396,7 +396,7 @@ impl Initiator {
             };
             Ok(codec)
         } else {
-            Err(Error::InvalidCertificate(plaintext))
+            Err(Error::InvalidCertificate(plaintext.into()))
         }
     }
 

sv2/noise-sv2/src/signature_message.rs

@@ -22,6 +22,7 @@
 // validity period.
 
 use core::convert::TryInto;
+use core::fmt;
 
 use secp256k1::{hashes::sha256, schnorr::Signature, Keypair, Message, Secp256k1, XOnlyPublicKey};
 
@@ -32,6 +33,7 @@ use secp256k1::{hashes::sha256, schnorr::Signature, Keypair, Message, Secp256k1,
 ///
 /// This structure ensures that messages are authenticated and valid only within
 /// a specified time window, using Schnorr signatures over the `secp256k1` elliptic curve.
+#[derive(Debug, PartialEq, Eq)]
 pub struct SignatureNoiseMessage {
     // Version of the protocol being used.
     pub version: u16,
@@ -43,6 +45,23 @@ pub struct SignatureNoiseMessage {
     pub signature: [u8; 64],
 }
 
+impl fmt::Display for SignatureNoiseMessage {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // write header
+        write!(
+            f,
+            "SignatureNoiseMessage {{ version: {}, valid_from: {}, not_valid_after: {}, signature: ",
+            self.version, self.valid_from, self.not_valid_after
+        )?;
+
+        // write signature as hex manually
+        for byte in &self.signature {
+            write!(f, "{:02x}", byte)?;
+        }
+
+        write!(f, " }}")
+    }
+}
 impl From<[u8; 74]> for SignatureNoiseMessage {
     // Converts a 74-byte array into a [`SignatureNoiseMessage`].
     //