From 6a42c4bd22b5f4c987652b1e8ff7b182881fbb4c Mon Sep 17 00:00:00 2001
From: Carlos Medeiros <carlos.medeiros@zondax.ch>
Date: Fri, 28 Feb 2025 09:58:17 +0000
Subject: [PATCH] add function to compute ed25519 pubkey

---
 bolos-impl/Cargo.toml            |  2 +-
 bolos-impl/src/crypto/ecfp256.rs | 19 +++++++++++++++++++
 bolos-mock/src/crypto/ecfp256.rs | 23 ++++++-----------------
 3 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/bolos-impl/Cargo.toml b/bolos-impl/Cargo.toml
index cc6b3a4..ee4641a 100644
--- a/bolos-impl/Cargo.toml
+++ b/bolos-impl/Cargo.toml
@@ -11,7 +11,7 @@ edition = "2018"
 bolos-common = { version = "0.1", path = "../bolos-common" }
 bolos-sys = { version = "0.1", path = "../bolos-sys" }
 zemu-sys = { version = "0.1", path = "../zemu" }
-
+ed25519-dalek = { version = "2.1.1", default-features = false }
 cfg-if = "1.0.0"
 no-std-compat = { version = "0.4" }
 
diff --git a/bolos-impl/src/crypto/ecfp256.rs b/bolos-impl/src/crypto/ecfp256.rs
index 04acc39..338e0eb 100644
--- a/bolos-impl/src/crypto/ecfp256.rs
+++ b/bolos-impl/src/crypto/ecfp256.rs
@@ -143,6 +143,25 @@ impl AsRef<[u8]> for PublicKey {
     }
 }
 
+pub fn public_from_bytes_ed25519(
+    bytes: &[u8; 32],
+    out: &mut MaybeUninit<PublicKey>,
+) -> Result<(), Error> {
+    use ed25519_dalek::{SigningKey, VerifyingKey};
+
+    // Initialize the PublicKey struct with the appropriate data
+    unsafe {
+        let out_ptr = out.as_mut_ptr();
+        (*out_ptr).0.W[0] = 0x02; // Add prefix for compressed format
+        (*out_ptr).0.W[1..33]
+            .copy_from_slice(&SigningKey::from_bytes(bytes).verifying_key().to_bytes());
+        (*out_ptr).0.W_len = 33; // Length includes the prefix byte
+        (*out_ptr).0.curve = Curve::Ed25519 as u32;
+    }
+
+    Ok(())
+}
+
 pub struct SecretKey<const B: usize> {
     mode: Mode,
     curve: Curve,
diff --git a/bolos-mock/src/crypto/ecfp256.rs b/bolos-mock/src/crypto/ecfp256.rs
index 4327f3d..f68b006 100644
--- a/bolos-mock/src/crypto/ecfp256.rs
+++ b/bolos-mock/src/crypto/ecfp256.rs
@@ -114,12 +114,7 @@ impl<const B: usize> SecretKey<B> {
         rand_chacha7::ChaCha8Rng::from_seed(seed)
     }
 
-    pub fn new(
-        _: Mode,
-        curve: Curve,
-        path: BIP32Path<B>,
-        ed25519_secret_key_bytes: Option<[u8; 32]>,
-    ) -> Self {
+    pub fn new(_: Mode, curve: Curve, path: BIP32Path<B>) -> Self {
         let bytes = match curve {
             Curve::Secp256K1 => {
                 let secret = k256::ecdsa::SigningKey::random(&mut Self::rng8(path));
@@ -132,17 +127,11 @@ impl<const B: usize> SecretKey<B> {
                 *secret.to_bytes().as_ref()
             }
             Curve::Ed25519 => {
-                if let Some(bytes) = ed25519_secret_key_bytes {
-                    let secret = ed25519_dalek::SigningKey::from_bytes(&bytes);
-                    secret.to_bytes()
-                } else {
-                    // Generate random bytes using the path if no bytes provided
-                    let mut bytes = [0u8; 32];
-                    let mut rng = Self::rng8(path);
-                    use rand_chacha8::rand_core::RngCore;
-                    rng.fill_bytes(&mut bytes);
-                    bytes
-                }
+                let mut bytes = [0u8; 32];
+                let mut rng = Self::rng8(path);
+                use rand_chacha8::rand_core::RngCore;
+                rng.fill_bytes(&mut bytes);
+                bytes
             }
             Curve::Stark256 => {
                 panic!("invalid curve passed to ecfp256 new")