fix(ext/node): export JWK public key (#25239)

Fixes https://github.com/denoland/deno/issues/18928

Signed-off-by: Divy Srivastava <dj.srivastava23@gmail.com>

1 files changed, 78 insertions, 0 deletions

diff --git a/ext/node/ops/crypto/keys.rs b/ext/node/ops/crypto/keys.rs
index eccd08564..7334fb8eb 100644
--- a/ext/node/ops/crypto/keys.rs
+++ b/ext/node/ops/crypto/keys.rs
@@ -235,6 +235,16 @@ impl RsaPssPrivateKey {
   }
 }
 
+impl EcPublicKey {
+  pub fn to_jwk(&self) -> Result<elliptic_curve::JwkEcKey, AnyError> {
+    match self {
+      EcPublicKey::P224(_) => Err(type_error("Unsupported JWK EC curve: P224")),
+      EcPublicKey::P256(key) => Ok(key.to_jwk()),
+      EcPublicKey::P384(key) => Ok(key.to_jwk()),
+    }
+  }
+}
+
 impl EcPrivateKey {
   /// Derives the public key from the private key.
   pub fn to_public_key(&self) -> EcPublicKey {
@@ -848,7 +858,63 @@ fn parse_rsa_pss_params(
   Ok(details)
 }
 
+use base64::prelude::BASE64_URL_SAFE_NO_PAD;
+
+fn bytes_to_b64(bytes: &[u8]) -> String {
+  BASE64_URL_SAFE_NO_PAD.encode(bytes)
+}
+
 impl AsymmetricPublicKey {
+  fn export_jwk(&self) -> Result<deno_core::serde_json::Value, AnyError> {
+    match self {
+      AsymmetricPublicKey::Ec(key) => {
+        let jwk = key.to_jwk()?;
+        Ok(deno_core::serde_json::json!(jwk))
+      }
+      AsymmetricPublicKey::X25519(key) => {
+        let bytes = key.as_bytes();
+        let jwk = deno_core::serde_json::json!({
+            "kty": "OKP",
+            "crv": "X25519",
+            "x": bytes_to_b64(bytes),
+        });
+        Ok(jwk)
+      }
+      AsymmetricPublicKey::Ed25519(key) => {
+        let bytes = key.to_bytes();
+        let jwk = deno_core::serde_json::json!({
+            "kty": "OKP",
+            "crv": "Ed25519",
+            "x": bytes_to_b64(&bytes),
+        });
+        Ok(jwk)
+      }
+      AsymmetricPublicKey::Rsa(key) => {
+        let n = key.n();
+        let e = key.e();
+
+        let jwk = deno_core::serde_json::json!({
+            "kty": "RSA",
+            "n": bytes_to_b64(&n.to_bytes_be()),
+            "e": bytes_to_b64(&e.to_bytes_be()),
+        });
+        Ok(jwk)
+      }
+      AsymmetricPublicKey::RsaPss(key) => {
+        let n = key.key.n();
+        let e = key.key.e();
+
+        let jwk = deno_core::serde_json::json!({
+            "kty": "RSA",
+            "n": bytes_to_b64(&n.to_bytes_be()),
+            "e": bytes_to_b64(&e.to_bytes_be()),
+        });
+        Ok(jwk)
+      }
+      _ => Err(type_error("jwk export not implemented for this key type")),
+    }
+  }
+
   fn export_der(&self, typ: &str) -> Result<Box<[u8]>, AnyError> {
     match typ {
       "pkcs1" => match self {
@@ -1849,6 +1915,18 @@ pub fn op_node_export_secret_key_b64url(
 }
 
 #[op2]
+#[serde]
+pub fn op_node_export_public_key_jwk(
+  #[cppgc] handle: &KeyObjectHandle,
+) -> Result<deno_core::serde_json::Value, AnyError> {
+  let public_key = handle
+    .as_public_key()
+    .ok_or_else(|| type_error("key is not an asymmetric public key"))?;
+
+  public_key.export_jwk()
+}
+
+#[op2]
 #[string]
 pub fn op_node_export_public_key_pem(
   #[cppgc] handle: &KeyObjectHandle,