From 369f87f657778822337ac8be88987b702fbc58c5 Mon Sep 17 00:00:00 2001
From: Tony Arcieri <bascule@gmail.com>
Date: Sat, 25 Apr 2026 09:51:40 -0600
Subject: [PATCH] pkcs8: impl `Decode`/`EncodePrivateKey` for
 `PrivateKeyInfoOwned`

---
 pkcs8/src/lib.rs              |  2 +-
 pkcs8/src/private_key_info.rs | 42 ++++++++++++++++++++++++++++-------
 2 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/pkcs8/src/lib.rs b/pkcs8/src/lib.rs
index 0ebde2cd0..6153e67dd 100644
--- a/pkcs8/src/lib.rs
+++ b/pkcs8/src/lib.rs
@@ -89,7 +89,7 @@ pub use spki::{
 
 #[cfg(feature = "alloc")]
 pub use {
-    crate::{private_key_info::PrivateKeyInfoOwned, traits::EncodePrivateKey},
+    crate::{private_key_info::allocating::PrivateKeyInfoOwned, traits::EncodePrivateKey},
     der::{Document, SecretDocument},
     spki::EncodePublicKey,
 };
diff --git a/pkcs8/src/private_key_info.rs b/pkcs8/src/private_key_info.rs
index 6b68e3524..09d96045f 100644
--- a/pkcs8/src/private_key_info.rs
+++ b/pkcs8/src/private_key_info.rs
@@ -377,10 +377,6 @@ where
 /// [`PrivateKeyInfo`] with [`AnyRef`] algorithm parameters, and `&[u8]` key.
 pub type PrivateKeyInfoRef<'a> = PrivateKeyInfo<AnyRef<'a>, &'a OctetStringRef, BitStringRef<'a>>;
 
-/// [`PrivateKeyInfo`] with [`Any`] algorithm parameters, and `Box<[u8]>` key.
-#[cfg(feature = "alloc")]
-pub type PrivateKeyInfoOwned = PrivateKeyInfo<Any, OctetString, BitString>;
-
 /// [`BitStringLike`] marks object that will act like a `BitString`.
 ///
 /// It will allow to get a [`BitStringRef`] that points back to the underlying bytes.
@@ -396,15 +392,39 @@ impl BitStringLike for BitStringRef<'_> {
 }
 
 #[cfg(feature = "alloc")]
-mod allocating {
+pub(crate) mod allocating {
     use super::*;
+    use crate::{DecodePrivateKey, EncodePrivateKey};
     use alloc::borrow::ToOwned;
     use core::borrow::Borrow;
     use der::referenced::*;
 
-    impl BitStringLike for BitString {
-        fn as_bit_string(&self) -> BitStringRef<'_> {
-            BitStringRef::from(self)
+    #[cfg(feature = "pem")]
+    use der::DecodePem;
+
+    /// [`PrivateKeyInfo`] with [`Any`] algorithm parameters, and `Box<[u8]>` key.
+    pub type PrivateKeyInfoOwned = PrivateKeyInfo<Any, OctetString, BitString>;
+
+    impl DecodePrivateKey for PrivateKeyInfoOwned {
+        fn from_pkcs8_der(bytes: &[u8]) -> Result<Self> {
+            Ok(Self::from_der(bytes)?)
+        }
+
+        #[cfg(feature = "pem")]
+        fn from_pkcs8_pem(pem: &str) -> Result<Self> {
+            Ok(Self::from_pem(pem)?)
+        }
+    }
+
+    impl EncodePrivateKey for PrivateKeyInfoOwned {
+        fn to_pkcs8_der(&self) -> Result<SecretDocument> {
+            self.try_into()
+        }
+    }
+
+    impl EncodePrivateKey for PrivateKeyInfoRef<'_> {
+        fn to_pkcs8_der(&self) -> Result<SecretDocument> {
+            self.try_into()
         }
     }
 
@@ -429,4 +449,10 @@ mod allocating {
             }
         }
     }
+
+    impl BitStringLike for BitString {
+        fn as_bit_string(&self) -> BitStringRef<'_> {
+            BitStringRef::from(self)
+        }
+    }
 }