16 files changed, 210 insertions, 12 deletions
diff --git a/core/src/async_utils/backoff.rs b/core/src/async_util/backoff.rs
index f7e131d..a231229 100644
--- a/core/src/async_utils/backoff.rs
+++ b/core/src/async_util/backoff.rs
@@ -12,7 +12,7 @@ use smol::Timer;
 /// # Examples
 ///
 /// ```
-/// use karyons_core::async_utils::Backoff;
+/// use karyons_core::async_util::Backoff;
 ///
 ///  async {
 ///     let backoff = Backoff::new(300, 3000);
diff --git a/core/src/async_utils/condvar.rs b/core/src/async_util/condvar.rs
index 814f78f..7396d0d 100644
--- a/core/src/async_utils/condvar.rs
+++ b/core/src/async_util/condvar.rs
@@ -8,7 +8,7 @@ use std::{
 
 use smol::lock::MutexGuard;
 
-use crate::utils::random_16;
+use crate::util::random_16;
 
 /// CondVar is an async version of <https://doc.rust-lang.org/std/sync/struct.Condvar.html>
 ///
@@ -19,7 +19,7 @@ use crate::utils::random_16;
 ///
 /// use smol::lock::Mutex;
 ///
-/// use karyons_core::async_utils::CondVar;
+/// use karyons_core::async_util::CondVar;
 ///
 ///  async {
 ///     
diff --git a/core/src/async_utils/condwait.rs b/core/src/async_util/condwait.rs
index e31fac3..cd4b269 100644
--- a/core/src/async_utils/condwait.rs
+++ b/core/src/async_util/condwait.rs
@@ -9,7 +9,7 @@ use super::CondVar;
 ///```
 /// use std::sync::Arc;
 ///
-/// use karyons_core::async_utils::CondWait;
+/// use karyons_core::async_util::CondWait;
 ///
 ///  async {
 ///     let cond_wait = Arc::new(CondWait::new());
diff --git a/core/src/async_utils/mod.rs b/core/src/async_util/mod.rs
index c871bad..c871bad 100644
--- a/core/src/async_utils/mod.rs
+++ b/core/src/async_util/mod.rs
diff --git a/core/src/async_utils/select.rs b/core/src/async_util/select.rs
index 9fe3c77..8f2f7f6 100644
--- a/core/src/async_utils/select.rs
+++ b/core/src/async_util/select.rs
@@ -12,7 +12,7 @@ use smol::future::Future;
 /// ```
 /// use std::future;
 ///
-/// use karyons_core::async_utils::{select, Either};
+/// use karyons_core::async_util::{select, Either};
 ///
 ///  async {
 ///     let fut1 = future::pending::<String>();
diff --git a/core/src/async_utils/task_group.rs b/core/src/async_util/task_group.rs
index afc9648..3fc0cb7 100644
--- a/core/src/async_utils/task_group.rs
+++ b/core/src/async_util/task_group.rs
@@ -14,7 +14,7 @@ use super::{select, CondWait, Either};
 ///
 /// use std::sync::Arc;
 ///
-/// use karyons_core::async_utils::TaskGroup;
+/// use karyons_core::async_util::TaskGroup;
 ///
 /// async {
 ///
diff --git a/core/src/async_utils/timeout.rs b/core/src/async_util/timeout.rs
index 7c55e1b..6ab35c4 100644
--- a/core/src/async_utils/timeout.rs
+++ b/core/src/async_util/timeout.rs
@@ -13,7 +13,7 @@ use crate::{error::Error, Result};
 /// ```
 /// use std::{future, time::Duration};
 ///
-/// use karyons_core::async_utils::timeout;
+/// use karyons_core::async_util::timeout;
 ///
 /// async {
 ///     let fut = future::pending::<()>();
diff --git a/core/src/error.rs b/core/src/error.rs
index 63b45d3..7c547c4 100644
--- a/core/src/error.rs
+++ b/core/src/error.rs
@@ -7,12 +7,18 @@ pub enum Error {
     #[error(transparent)]
     IO(#[from] std::io::Error),
 
+    #[error("TryInto Error: {0}")]
+    TryInto(&'static str),
+
     #[error("Timeout Error")]
     Timeout,
 
     #[error("Path Not Found Error: {0}")]
     PathNotFound(&'static str),
 
+    #[error(transparent)]
+    Ed25519(#[from] ed25519_dalek::ed25519::Error),
+
     #[error("Channel Send Error: {0}")]
     ChannelSend(String),
 
diff --git a/core/src/event.rs b/core/src/event.rs
index 0503e88..f2c5510 100644
--- a/core/src/event.rs
+++ b/core/src/event.rs
@@ -12,7 +12,7 @@ use smol::{
     lock::Mutex,
 };
 
-use crate::{utils::random_16, Result};
+use crate::{util::random_16, Result};
 
 pub type ArcEventSys<T> = Arc<EventSys<T>>;
 pub type WeakEventSys<T> = Weak<EventSys<T>>;
diff --git a/core/src/key_pair.rs b/core/src/key_pair.rs
new file mode 100644
index 0000000..4016351
--- /dev/null
+++ b/core/src/key_pair.rs
@@ -0,0 +1,189 @@
+use ed25519_dalek::{Signer as _, Verifier as _};
+use rand::rngs::OsRng;
+
+use crate::{error::Error, Result};
+
+/// key cryptography type
+pub enum KeyPairType {
+    Ed25519,
+}
+
+/// A Public key
+pub struct PublicKey(PublicKeyInner);
+
+/// A Secret key
+pub struct SecretKey(Vec<u8>);
+
+impl PublicKey {
+    pub fn as_bytes(&self) -> &[u8] {
+        self.0.as_bytes()
+    }
+
+    /// Verify a signature on a message with this public key.
+    pub fn verify(&self, msg: &[u8], signature: &[u8]) -> Result<()> {
+        self.0.verify(msg, signature)
+    }
+}
+
+impl PublicKey {
+    pub fn from_bytes(kp_type: &KeyPairType, pk: &[u8]) -> Result<Self> {
+        Ok(Self(PublicKeyInner::from_bytes(kp_type, pk)?))
+    }
+}
+
+/// A KeyPair.
+#[derive(Clone)]
+pub struct KeyPair(KeyPairInner);
+
+impl KeyPair {
+    /// Generate a new random keypair.
+    pub fn generate(kp_type: &KeyPairType) -> Self {
+        Self(KeyPairInner::generate(kp_type))
+    }
+
+    /// Sign a message using the private key.
+    pub fn sign(&self, msg: &[u8]) -> Vec<u8> {
+        self.0.sign(msg)
+    }
+
+    /// Get the public key of this keypair.
+    pub fn public(&self) -> PublicKey {
+        self.0.public()
+    }
+
+    /// Get the secret key of this keypair.
+    pub fn secret(&self) -> SecretKey {
+        self.0.secret()
+    }
+}
+
+/// An extension trait, adding essential methods to all [`KeyPair`] types.
+trait KeyPairExt {
+    /// Sign a message using the private key.
+    fn sign(&self, msg: &[u8]) -> Vec<u8>;
+
+    /// Get the public key of this keypair.
+    fn public(&self) -> PublicKey;
+
+    /// Get the secret key of this keypair.
+    fn secret(&self) -> SecretKey;
+}
+
+#[derive(Clone)]
+enum KeyPairInner {
+    Ed25519(Ed25519KeyPair),
+}
+
+impl KeyPairInner {
+    fn generate(kp_type: &KeyPairType) -> Self {
+        match kp_type {
+            KeyPairType::Ed25519 => Self::Ed25519(Ed25519KeyPair::generate()),
+        }
+    }
+}
+
+impl KeyPairExt for KeyPairInner {
+    fn sign(&self, msg: &[u8]) -> Vec<u8> {
+        match self {
+            KeyPairInner::Ed25519(kp) => kp.sign(msg),
+        }
+    }
+
+    fn public(&self) -> PublicKey {
+        match self {
+            KeyPairInner::Ed25519(kp) => kp.public(),
+        }
+    }
+
+    fn secret(&self) -> SecretKey {
+        match self {
+            KeyPairInner::Ed25519(kp) => kp.secret(),
+        }
+    }
+}
+
+#[derive(Clone)]
+struct Ed25519KeyPair(ed25519_dalek::SigningKey);
+
+impl Ed25519KeyPair {
+    fn generate() -> Self {
+        Self(ed25519_dalek::SigningKey::generate(&mut OsRng))
+    }
+}
+
+impl KeyPairExt for Ed25519KeyPair {
+    fn sign(&self, msg: &[u8]) -> Vec<u8> {
+        self.0.sign(msg).to_bytes().to_vec()
+    }
+
+    fn public(&self) -> PublicKey {
+        PublicKey(PublicKeyInner::Ed25519(Ed25519PublicKey(
+            self.0.verifying_key(),
+        )))
+    }
+
+    fn secret(&self) -> SecretKey {
+        SecretKey(self.0.to_bytes().to_vec())
+    }
+}
+
+/// An extension trait, adding essential methods to all [`PublicKey`] types.
+trait PublicKeyExt {
+    fn as_bytes(&self) -> &[u8];
+
+    /// Verify a signature on a message with this public key.
+    fn verify(&self, msg: &[u8], signature: &[u8]) -> Result<()>;
+}
+
+enum PublicKeyInner {
+    Ed25519(Ed25519PublicKey),
+}
+
+impl PublicKeyInner {
+    pub fn from_bytes(kp_type: &KeyPairType, pk: &[u8]) -> Result<Self> {
+        match kp_type {
+            KeyPairType::Ed25519 => Ok(Self::Ed25519(Ed25519PublicKey::from_bytes(pk)?)),
+        }
+    }
+}
+
+impl PublicKeyExt for PublicKeyInner {
+    fn as_bytes(&self) -> &[u8] {
+        match self {
+            Self::Ed25519(pk) => pk.as_bytes(),
+        }
+    }
+
+    fn verify(&self, msg: &[u8], signature: &[u8]) -> Result<()> {
+        match self {
+            Self::Ed25519(pk) => pk.verify(msg, signature),
+        }
+    }
+}
+
+struct Ed25519PublicKey(ed25519_dalek::VerifyingKey);
+
+impl Ed25519PublicKey {
+    pub fn from_bytes(pk: &[u8]) -> Result<Self> {
+        let pk_bytes: [u8; 32] = pk
+            .try_into()
+            .map_err(|_| Error::TryInto("Failed to convert slice to [u8; 32]"))?;
+
+        Ok(Self(ed25519_dalek::VerifyingKey::from_bytes(&pk_bytes)?))
+    }
+}
+
+impl PublicKeyExt for Ed25519PublicKey {
+    fn as_bytes(&self) -> &[u8] {
+        self.0.as_bytes()
+    }
+
+    fn verify(&self, msg: &[u8], signature: &[u8]) -> Result<()> {
+        let sig_bytes: [u8; 64] = signature
+            .try_into()
+            .map_err(|_| Error::TryInto("Failed to convert slice to [u8; 64]"))?;
+        self.0
+            .verify(msg, &ed25519_dalek::Signature::from_bytes(&sig_bytes))?;
+        Ok(())
+    }
+}
diff --git a/core/src/lib.rs b/core/src/lib.rs
index 67e6610..276ed89 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -1,19 +1,22 @@
 /// A set of helper tools and functions.
-pub mod utils;
+pub mod util;
 
 /// A module containing async utilities that work with the
 /// [`smol`](https://github.com/smol-rs/smol) async runtime.
-pub mod async_utils;
+pub mod async_util;
 
 /// Represents karyons's Core Error.
 pub mod error;
 
-/// [`event::EventSys`] Implementation
+/// [`event::EventSys`] implementation.
 pub mod event;
 
 /// A simple publish-subscribe system [`Read More`](./pubsub/struct.Publisher.html)
 pub mod pubsub;
 
+/// A cryptographic key pair
+pub mod key_pair;
+
 use smol::Executor as SmolEx;
 use std::sync::Arc;
 
diff --git a/core/src/pubsub.rs b/core/src/pubsub.rs
index 4cc0ab7..306d42f 100644
--- a/core/src/pubsub.rs
+++ b/core/src/pubsub.rs
@@ -3,7 +3,7 @@ use std::{collections::HashMap, sync::Arc};
 use log::error;
 use smol::lock::Mutex;
 
-use crate::{utils::random_16, Result};
+use crate::{util::random_16, Result};
 
 pub type ArcPublisher<T> = Arc<Publisher<T>>;
 pub type SubscriptionID = u16;
diff --git a/core/src/utils/decode.rs b/core/src/util/decode.rs
index a8a6522..a8a6522 100644
--- a/core/src/utils/decode.rs
+++ b/core/src/util/decode.rs
diff --git a/core/src/utils/encode.rs b/core/src/util/encode.rs
index 7d1061b..7d1061b 100644
--- a/core/src/utils/encode.rs
+++ b/core/src/util/encode.rs
diff --git a/core/src/utils/mod.rs b/core/src/util/mod.rs
index a3c3f50..a3c3f50 100644
--- a/core/src/utils/mod.rs
+++ b/core/src/util/mod.rs
diff --git a/core/src/utils/path.rs b/core/src/util/path.rs
index 2cd900a..2cd900a 100644
--- a/core/src/utils/path.rs
+++ b/core/src/util/path.rs