* Move ffi type container to boring-additions

* Use boring::derive for EC and ED instead of own implementation

boring-additions/src/evp/mod.rs

@@ -0,0 +1,3 @@
+mod types;
+
+pub use types::*;

boring-additions/src/evp/types.rs

@@ -0,0 +1,60 @@
+use std::{
+    ops::{Deref, DerefMut},
+    ptr::NonNull,
+};
+
+use foreign_types::{ForeignType, ForeignTypeRef, Opaque};
+
+pub struct EvpPkeyCtxRef(Opaque);
+
+unsafe impl ForeignTypeRef for EvpPkeyCtxRef {
+    type CType = boring_sys::EVP_PKEY_CTX;
+}
+
+unsafe impl Sync for EvpPkeyCtxRef {}
+unsafe impl Send for EvpPkeyCtxRef {}
+
+unsafe impl Sync for EvpPkeyCtx {}
+unsafe impl Send for EvpPkeyCtx {}
+
+pub struct EvpPkeyCtx(NonNull<boring_sys::EVP_PKEY_CTX>);
+unsafe impl ForeignType for EvpPkeyCtx {
+    type CType = boring_sys::EVP_PKEY_CTX;
+
+    type Ref = EvpPkeyCtxRef;
+
+    unsafe fn from_ptr(ptr: *mut Self::CType) -> Self {
+        Self(NonNull::new_unchecked(ptr))
+    }
+
+    fn as_ptr(&self) -> *mut Self::CType {
+        self.0.as_ptr()
+    }
+}
+impl Drop for EvpPkeyCtx {
+    fn drop(&mut self) {
+        unsafe {
+            boring_sys::EVP_PKEY_CTX_free(self.0.as_ptr());
+        }
+    }
+}
+
+impl core::fmt::Debug for EvpPkeyCtx {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_tuple("EvpPkeyCtx").field(&self.0).finish()
+    }
+}
+
+impl Deref for EvpPkeyCtx {
+    type Target = EvpPkeyCtxRef;
+
+    fn deref(&self) -> &EvpPkeyCtxRef {
+        unsafe { EvpPkeyCtxRef::from_ptr(self.as_ptr()) }
+    }
+}
+
+impl DerefMut for EvpPkeyCtx {
+    fn deref_mut(&mut self) -> &mut EvpPkeyCtxRef {
+        unsafe { EvpPkeyCtxRef::from_ptr_mut(self.as_ptr()) }
+    }
+}