refactor(serde_v8): split ZeroCopyBuf into JsBuffer and ToJsBuffer (#19566)

`ZeroCopyBuf` was convenient to use, but sometimes it did hide details
that some copies were necessary in certain cases. Also it made it way to easy
for the caller to pass around and convert into different values. This commit
splits `ZeroCopyBuf` into `JsBuffer` (an array buffer coming from V8) and
`ToJsBuffer` (a Rust buffer that will be converted into a V8 array buffer).

As a result some magical conversions were removed (they were never used)
limiting the API surface and preparing for changes in #19534.

1 files changed, 27 insertions, 18 deletions

diff --git a/ext/crypto/shared.rs b/ext/crypto/shared.rs
index 4ecb35dc2..109f51fa1 100644
--- a/ext/crypto/shared.rs
+++ b/ext/crypto/shared.rs
@@ -5,7 +5,8 @@ use std::borrow::Cow;
 use deno_core::error::custom_error;
 use deno_core::error::type_error;
 use deno_core::error::AnyError;
-use deno_core::ZeroCopyBuf;
+use deno_core::JsBuffer;
+use deno_core::ToJsBuffer;
 use elliptic_curve::sec1::ToEncodedPoint;
 use rsa::pkcs1::DecodeRsaPrivateKey;
 use rsa::pkcs1::EncodeRsaPublicKey;
@@ -46,19 +47,27 @@ pub enum EcNamedCurve {
   P521,
 }
 
-#[derive(Serialize, Deserialize)]
+#[derive(Deserialize)]
 #[serde(rename_all = "lowercase", tag = "type", content = "data")]
-pub enum RawKeyData {
-  Secret(ZeroCopyBuf),
-  Private(ZeroCopyBuf),
-  Public(ZeroCopyBuf),
+pub enum V8RawKeyData {
+  Secret(JsBuffer),
+  Private(JsBuffer),
+  Public(JsBuffer),
 }
 
-impl RawKeyData {
+#[derive(Serialize)]
+#[serde(rename_all = "lowercase", tag = "type", content = "data")]
+pub enum RustRawKeyData {
+  Secret(ToJsBuffer),
+  Private(ToJsBuffer),
+  Public(ToJsBuffer),
+}
+
+impl V8RawKeyData {
   pub fn as_rsa_public_key(&self) -> Result<Cow<'_, [u8]>, AnyError> {
     match self {
-      RawKeyData::Public(data) => Ok(Cow::Borrowed(data)),
-      RawKeyData::Private(data) => {
+      V8RawKeyData::Public(data) => Ok(Cow::Borrowed(data)),
+      V8RawKeyData::Private(data) => {
         let private_key = RsaPrivateKey::from_pkcs1_der(data)
           .map_err(|_| type_error("expected valid private key"))?;
 
@@ -75,55 +84,55 @@ impl RawKeyData {
 
   pub fn as_rsa_private_key(&self) -> Result<&[u8], AnyError> {
     match self {
-      RawKeyData::Private(data) => Ok(data),
+      V8RawKeyData::Private(data) => Ok(data),
       _ => Err(type_error("expected private key")),
     }
   }
 
   pub fn as_secret_key(&self) -> Result<&[u8], AnyError> {
     match self {
-      RawKeyData::Secret(data) => Ok(data),
+      V8RawKeyData::Secret(data) => Ok(data),
       _ => Err(type_error("expected secret key")),
     }
   }
 
   pub fn as_ec_public_key_p256(&self) -> Result<p256::EncodedPoint, AnyError> {
     match self {
-      RawKeyData::Public(data) => {
+      V8RawKeyData::Public(data) => {
         // public_key is a serialized EncodedPoint
         p256::EncodedPoint::from_bytes(data)
           .map_err(|_| type_error("expected valid public EC key"))
       }
-      RawKeyData::Private(data) => {
+      V8RawKeyData::Private(data) => {
         let signing_key = p256::SecretKey::from_pkcs8_der(data)
           .map_err(|_| type_error("expected valid private EC key"))?;
         Ok(signing_key.public_key().to_encoded_point(false))
       }
       // Should never reach here.
-      RawKeyData::Secret(_) => unreachable!(),
+      V8RawKeyData::Secret(_) => unreachable!(),
     }
   }
 
   pub fn as_ec_public_key_p384(&self) -> Result<p384::EncodedPoint, AnyError> {
     match self {
-      RawKeyData::Public(data) => {
+      V8RawKeyData::Public(data) => {
         // public_key is a serialized EncodedPoint
         p384::EncodedPoint::from_bytes(data)
           .map_err(|_| type_error("expected valid public EC key"))
       }
-      RawKeyData::Private(data) => {
+      V8RawKeyData::Private(data) => {
         let signing_key = p384::SecretKey::from_pkcs8_der(data)
           .map_err(|_| type_error("expected valid private EC key"))?;
         Ok(signing_key.public_key().to_encoded_point(false))
       }
       // Should never reach here.
-      RawKeyData::Secret(_) => unreachable!(),
+      V8RawKeyData::Secret(_) => unreachable!(),
     }
   }
 
   pub fn as_ec_private_key(&self) -> Result<&[u8], AnyError> {
     match self {
-      RawKeyData::Private(data) => Ok(data),
+      V8RawKeyData::Private(data) => Ok(data),
       _ => Err(type_error("expected private key")),
     }
   }