Move behind compile-time feature

apps/desktop/desktop_native/fido2_client/Cargo.toml

@@ -5,10 +5,14 @@ license = { workspace = true }
 version = { workspace = true }
 publish = { workspace = true }
 
+[features]
+default = []
+ctap-hid-fido2 = ["dep:ctap-hid-fido2", "dep:pinentry", "dep:secrecy"]
+
 [dependencies]
 base64 = { workspace = true }
-ctap-hid-fido2 = "3.5.1"
-pinentry = "0.5.0"
+ctap-hid-fido2 = { version = "3.5.1", optional = true }
+pinentry = { version = "0.5.0", optional = true}
 serde = { workspace = true, features = ["derive"] }
-secrecy = "0.8.0"
+secrecy = { version = "0.8.0", optional = true }
 sha2 = { workspace = true }

apps/desktop/desktop_native/fido2_client/src/ctap_hid_fido2.rs

@@ -11,6 +11,12 @@ use crate::{
     PublicKeyCredentialRequestOptions,
 };
 
+/// Depending on the platform API, the platform MAY do this for you, or may require you to do it manually.
+fn prf_to_hmac(prf_salt: &[u8]) -> [u8; 32] {
+    use sha2::Digest;
+    sha2::Sha256::digest(&[b"WebAuthn PRF".as_slice(), &[0], prf_salt].concat()).into()
+}
+
 fn get_pin() -> Option<String> {
     if let Some(mut input) = PassphraseInput::with_default_binary() {
         input

apps/desktop/desktop_native/fido2_client/src/lib.rs

@@ -1,20 +1,13 @@
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
+#[cfg(feature = "ctap-hid-fido2")]
 mod ctap_hid_fido2;
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
+#[cfg(feature = "ctap-hid-fido2")]
 use ctap_hid_fido2::*;
 
-#[cfg(not(all(target_os = "linux", target_env = "gnu")))]
+#[cfg(not(feature = "ctap-hid-fido2"))]
 mod unimplemented;
-#[cfg(not(all(target_os = "linux", target_env = "gnu")))]
+#[cfg(not(feature = "ctap-hid-fido2"))]
 use unimplemented::*;
 
-#[cfg(all(target_os = "linux", target_env = "gnu"))]
-/// Depending on the platform API, the platform MAY do this for you, or may require you to do it manually.
-fn prf_to_hmac(prf_salt: &[u8]) -> [u8; 32] {
-    use sha2::Digest;
-    sha2::Sha256::digest(&[b"WebAuthn PRF".as_slice(), &[0], prf_salt].concat()).into()
-}
-
 #[derive(Debug, PartialEq, Clone)]
 pub enum UserVerification {
     Discouraged,