pkcs8: replace subtle with ctutils

pkcs8/Cargo.toml

@@ -21,9 +21,9 @@ der = { version = "0.8.0-rc.12", features = ["oid"] }
 spki = "0.8"
 
 # optional dependencies
-rand_core = { version = "0.10", optional = true, default-features = false }
+ctutils = { version = "0.4", optional = true }
 pkcs5 = { version = "0.8", optional = true, features = ["rand_core"] }
-subtle = { version = "2", optional = true, default-features = false }
+rand_core = { version = "0.10", optional = true, default-features = false }
 
 [dev-dependencies]
 hex-literal = "1"

pkcs8/src/private_key_info.rs

@@ -9,23 +9,20 @@ use der::{
 };
 use spki::AlgorithmIdentifier;
 
+#[cfg(feature = "ctutils")]
+use ctutils::{Choice, CtEq};
+#[cfg(feature = "pem")]
+use der::pem::PemLabel;
 #[cfg(feature = "alloc")]
 use der::{
     SecretDocument,
     asn1::{Any, BitString, OctetString},
 };
-
 #[cfg(feature = "encryption")]
 use {
     crate::EncryptedPrivateKeyInfoRef, der::zeroize::Zeroizing, pkcs5::pbes2, rand_core::CryptoRng,
 };
 
-#[cfg(feature = "pem")]
-use der::pem::PemLabel;
-
-#[cfg(feature = "subtle")]
-use subtle::{Choice, ConstantTimeEq};
-
 /// Context-specific tag number for attributes.
 const ATTRIBUTES_TAG: TagNumber = TagNumber(0);
 
@@ -336,8 +333,8 @@ impl<Params, Key, PubKey> PemLabel for PrivateKeyInfo<Params, Key, PubKey> {
     const PEM_LABEL: &'static str = "PRIVATE KEY";
 }
 
-#[cfg(feature = "subtle")]
-impl<Params, Key, PubKey> ConstantTimeEq for PrivateKeyInfo<Params, Key, PubKey>
+#[cfg(feature = "ctutils")]
+impl<Params, Key, PubKey> CtEq for PrivateKeyInfo<Params, Key, PubKey>
 where
     Params: Eq,
     Key: PartialEq + AsRef<[u8]>,
@@ -353,7 +350,7 @@ where
     }
 }
 
-#[cfg(feature = "subtle")]
+#[cfg(feature = "ctutils")]
 impl<Params, Key, PubKey> Eq for PrivateKeyInfo<Params, Key, PubKey>
 where
     Params: Eq,
@@ -362,7 +359,7 @@ where
 {
 }
 
-#[cfg(feature = "subtle")]
+#[cfg(feature = "ctutils")]
 impl<Params, Key, PubKey> PartialEq for PrivateKeyInfo<Params, Key, PubKey>
 where
     Params: Eq,

pkcs8/tests/private_key.rs

@@ -194,7 +194,7 @@ fn encode_ed25519_der_v1() {
 }
 
 #[test]
-#[cfg(all(feature = "alloc", feature = "subtle"))]
+#[cfg(all(feature = "alloc", feature = "ctutils"))]
 fn encode_ed25519_der_v2() {
     let private_key = PrivateKeyInfoRef::try_from(ED25519_DER_V2_EXAMPLE).unwrap();
     let private_der = private_key.to_der().unwrap();