refactor: 将 DTLS 本地依赖迁移到 libs 目录

libs/dtls/src/curve/mod.rs

@@ -0,0 +1,17 @@
+pub mod named_curve;
+
+// https://www.iana.org/assignments/tls-parameters/tls-parameters.xhtml#tls-parameters-10
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+pub enum EllipticCurveType {
+    NamedCurve = 0x03,
+    Unsupported,
+}
+
+impl From<u8> for EllipticCurveType {
+    fn from(val: u8) -> Self {
+        match val {
+            0x03 => EllipticCurveType::NamedCurve,
+            _ => EllipticCurveType::Unsupported,
+        }
+    }
+}

libs/dtls/src/curve/named_curve.rs

@@ -0,0 +1,83 @@
+use rand_core::OsRng; // requires 'getrandom' feature
+
+use crate::error::*;
+
+// https://www.iana.org/assignments/tls-parameters/tls-parameters.xml#tls-parameters-8
+#[repr(u16)]
+#[derive(Copy, Clone, PartialEq, Eq, Debug)]
+pub enum NamedCurve {
+    Unsupported = 0x0000,
+    P256 = 0x0017,
+    P384 = 0x0018,
+    X25519 = 0x001d,
+}
+
+impl From<u16> for NamedCurve {
+    fn from(val: u16) -> Self {
+        match val {
+            0x0017 => NamedCurve::P256,
+            0x0018 => NamedCurve::P384,
+            0x001d => NamedCurve::X25519,
+            _ => NamedCurve::Unsupported,
+        }
+    }
+}
+
+pub(crate) enum NamedCurvePrivateKey {
+    EphemeralSecretP256(p256::ecdh::EphemeralSecret),
+    EphemeralSecretP384(p384::ecdh::EphemeralSecret),
+    StaticSecretX25519(x25519_dalek::StaticSecret),
+}
+
+pub struct NamedCurveKeypair {
+    pub(crate) curve: NamedCurve,
+    pub(crate) public_key: Vec<u8>,
+    pub(crate) private_key: NamedCurvePrivateKey,
+}
+
+fn elliptic_curve_keypair(curve: NamedCurve) -> Result<NamedCurveKeypair> {
+    let (public_key, private_key) = match curve {
+        NamedCurve::P256 => {
+            let secret_key = p256::ecdh::EphemeralSecret::random(&mut OsRng);
+            let public_key = p256::EncodedPoint::from(secret_key.public_key());
+            (
+                public_key.as_bytes().to_vec(),
+                NamedCurvePrivateKey::EphemeralSecretP256(secret_key),
+            )
+        }
+        NamedCurve::P384 => {
+            let secret_key = p384::ecdh::EphemeralSecret::random(&mut OsRng);
+            let public_key = p384::EncodedPoint::from(secret_key.public_key());
+            (
+                public_key.as_bytes().to_vec(),
+                NamedCurvePrivateKey::EphemeralSecretP384(secret_key),
+            )
+        }
+        NamedCurve::X25519 => {
+            let secret_key = x25519_dalek::StaticSecret::random_from_rng(OsRng);
+            let public_key = x25519_dalek::PublicKey::from(&secret_key);
+            (
+                public_key.as_bytes().to_vec(),
+                NamedCurvePrivateKey::StaticSecretX25519(secret_key),
+            )
+        }
+        _ => return Err(Error::ErrInvalidNamedCurve),
+    };
+
+    Ok(NamedCurveKeypair {
+        curve,
+        public_key,
+        private_key,
+    })
+}
+
+impl NamedCurve {
+    pub fn generate_keypair(&self) -> Result<NamedCurveKeypair> {
+        match *self {
+            NamedCurve::X25519 => elliptic_curve_keypair(NamedCurve::X25519),
+            NamedCurve::P256 => elliptic_curve_keypair(NamedCurve::P256),
+            NamedCurve::P384 => elliptic_curve_keypair(NamedCurve::P384),
+            _ => Err(Error::ErrInvalidNamedCurve),
+        }
+    }
+}