keyfork-derive-path-data: initial commit

Cargo.lock

@@ -893,6 +893,13 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "keyfork-derive-path-data"
+version = "0.1.0"
+dependencies = [
+ "keyfork-derive-util",
+]
+
 [[package]]
 name = "keyfork-derive-util"
 version = "0.1.0"
@@ -954,6 +961,7 @@ version = "0.1.0"
 dependencies = [
  "bincode",
  "hex-literal",
+ "keyfork-derive-path-data",
  "keyfork-derive-util",
  "keyfork-frame",
  "keyfork-mnemonic-util",

Cargo.toml

@@ -3,9 +3,10 @@
 resolver = "2"
 members = [
     "keyfork",
-    "keyfork-derive-util",
     "keyfork-derive-key",
     "keyfork-derive-openpgp",
+    "keyfork-derive-path-data",
+    "keyfork-derive-util",
     "keyfork-frame",
     "keyfork-mnemonic-util",
     "keyfork-plumbing",

keyfork-derive-path-data/Cargo.toml

@@ -0,0 +1,9 @@
+[package]
+name = "keyfork-derive-path-data"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+keyfork-derive-util = { version = "0.1.0", path = "../keyfork-derive-util", default-features = false }

keyfork-derive-path-data/src/lib.rs

@@ -0,0 +1,26 @@
+use keyfork_derive_util::{DerivationPath, DerivationIndex};
+
+pub static OPENPGP: DerivationIndex = DerivationIndex::new_unchecked(7366512, true);
+
+pub enum Target {
+    OpenPGP(DerivationIndex),
+}
+
+impl std::fmt::Display for Target {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::OpenPGP(account) => {
+                write!(f, "OpenPGP key (account {account})")
+            }
+        }
+    }
+}
+
+/// Determine the closest [`Target`] for the given path. This method is intended to be used by
+/// `keyforkd` to provide an optional textual prompt to what a client is attempting to derive.
+pub fn guess_target(path: &DerivationPath) -> Option<Target> {
+    Some(match Vec::from_iter(path.iter())[..] {
+        [t, index] if t == &OPENPGP => Target::OpenPGP(index.clone()),
+        _ => return None,
+    })
+}

keyfork-derive-util/src/index.rs

@@ -25,11 +25,16 @@ impl DerivationIndex {
     /// # Errors
     ///
     /// Returns an error if the index is larger than the hardened flag.
-    pub fn new(index: u32, hardened: bool) -> Result<Self> {
+    pub const fn new(index: u32, hardened: bool) -> Result<Self> {
         if index & (0b1 << 31) > 0 {
             return Err(Error::IndexTooLarge(index));
         }
-        Ok(Self(index | (u32::from(hardened) << 31)))
+        Ok(Self(index | ((hardened as u32) << 31)))
+    }
+
+    #[doc(hidden)]
+    pub const fn new_unchecked(index: u32, hardened: bool) -> Self {
+        Self(index | ((hardened as u32) << 31))
     }
 
     /*
@@ -39,6 +44,10 @@ impl DerivationIndex {
     }
     */
 
+    pub fn inner(&self) -> u32 {
+        self.0
+    }
+
     pub(crate) fn to_bytes(&self) -> [u8; 4] {
         self.0.to_be_bytes()
     }

keyforkd/Cargo.toml

@@ -28,6 +28,7 @@ tower = { version = "0.4.13", features = ["tokio", "util"] }
 # Personally audited
 thiserror = "1.0.47"
 serde = { version = "1.0.186", features = ["derive"] }
+keyfork-derive-path-data = { version = "0.1.0", path = "../keyfork-derive-path-data" }
 
 [dev-dependencies]
 hex-literal = "0.4.1"

keyforkd/src/service.rs

@@ -1,7 +1,9 @@
 use std::{future::Future, pin::Pin, sync::Arc, task::Poll};
 
 use keyfork_derive_util::request::{DerivationError, DerivationRequest, DerivationResponse};
+use keyfork_derive_path_data::guess_target;
 use tower::Service;
+use tracing::info;
 
 // NOTE: All values implemented in Keyforkd must implement Clone with low overhead, either by
 // using an Arc or by having a small signature. This is because Service<T> takes &mut self.
@@ -50,6 +52,14 @@ impl Service<DerivationRequest> for Keyforkd {
             if len < 2 {
                 return Err(KeyforkdRequestError::InvalidDerivationLength(len));
             }
+
+            #[cfg(feature = "tracing")]
+            if let Some(target) = guess_target(req.path()) {
+                info!("Deriving path: {target}");
+            } else {
+                info!("Deriving path: {}", req.path());
+            }
+
             req.derive_with_master_seed((*seed).clone())
                 .map_err(KeyforkdRequestError::from)
         })