From d142ae6117cd664d8e471ceb16b85c904f3f2352 Mon Sep 17 00:00:00 2001
From: frijolo <frijolin@proton.me>
Date: Sun, 15 Mar 2026 19:59:41 +0100
Subject: [PATCH 1/2] feat: expose custom transport API via from_transport()

Add a public BitBox::from_transport() that accepts any communication::ReadWrite
implementation and performs the U2F-HID framing internally. This lets callers
delegate raw USB I/O to platform-specific code (e.g. Android, where USB access
requires Java APIs unavailable to hidapi) by implementing only the ReadWrite
trait over their transport.

- Make the communication module public to expose the ReadWrite trait and Error.
- Remove the feature gate on FIRMWARE_CMD so from_transport (available without
  the usb/wasm/simulator features) can perform the framing.
---
 src/communication.rs |  1 -
 src/lib.rs           | 34 +++++++++++++++++++++++++---------
 2 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/src/communication.rs b/src/communication.rs
index 393148d..7be601f 100644
--- a/src/communication.rs
+++ b/src/communication.rs
@@ -6,7 +6,6 @@ use crate::util::Threading;
 use async_trait::async_trait;
 use thiserror::Error;
 
-#[cfg(any(feature = "wasm", feature = "usb", feature = "simulator"))]
 pub const FIRMWARE_CMD: u8 = 0x80 + 0x40 + 0x01;
 
 #[derive(Error, Debug)]
diff --git a/src/lib.rs b/src/lib.rs
index e837f27..e3968e5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -51,6 +51,7 @@ pub use util::Threading;
 use communication::HwwCommunication;
 
 pub use communication::Product;
+pub use communication::{Error as CommunicationError, ReadWrite};
 
 const OP_I_CAN_HAS_HANDSHAEK: u8 = b'h';
 const OP_HER_COMEZ_TEH_HANDSHAEK: u8 = b'H';
@@ -86,6 +87,25 @@ impl<R: Runtime> BitBox<R> {
         })
     }
 
+    /// Creates a new BitBox instance from a custom transport.
+    ///
+    /// The `transport` is a raw byte channel to the device (HID reports); this method wraps it
+    /// in the U2F-HID framing layer internally, so callers only need to implement
+    /// [`ReadWrite`] over their platform-specific transport.
+    ///
+    /// This enables use cases where USB I/O must be delegated to platform-specific code
+    /// (e.g., Android, where USB access requires Java APIs unavailable to `hidapi`).
+    pub async fn from_transport(
+        transport: Box<dyn communication::ReadWrite>,
+        noise_config: Box<dyn NoiseConfig>,
+    ) -> Result<BitBox<R>, Error> {
+        let comm = Box::new(communication::U2fHidCommunication::from(
+            transport,
+            communication::FIRMWARE_CMD,
+        ));
+        Self::from(comm, noise_config).await
+    }
+
     /// Creates a new BitBox instance. The provided noise config determines how the pairing
     /// information is persisted. Use `usb::get_any_bitbox02()` to find a BitBox02 HID device.
     ///
@@ -96,11 +116,7 @@ impl<R: Runtime> BitBox<R> {
         device: hidapi::HidDevice,
         noise_config: Box<dyn NoiseConfig>,
     ) -> Result<BitBox<R>, Error> {
-        let comm = Box::new(communication::U2fHidCommunication::from(
-            Box::new(crate::usb::HidDevice::new(device)),
-            communication::FIRMWARE_CMD,
-        ));
-        Self::from(comm, noise_config).await
+        Self::from_transport(Box::new(crate::usb::HidDevice::new(device)), noise_config).await
     }
 
     #[cfg(feature = "simulator")]
@@ -108,11 +124,11 @@ impl<R: Runtime> BitBox<R> {
         endpoint: Option<&str>,
         noise_config: Box<dyn NoiseConfig>,
     ) -> Result<BitBox<R>, Error> {
-        let comm = Box::new(communication::U2fHidCommunication::from(
+        Self::from_transport(
             crate::simulator::try_connect::<R>(endpoint).await?,
-            communication::FIRMWARE_CMD,
-        ));
-        Self::from(comm, noise_config).await
+            noise_config,
+        )
+        .await
     }
 
     /// Invokes the device unlock and pairing.

From 7ce956c254ab6e2011f29b9bdb22bc83384bec8f Mon Sep 17 00:00:00 2001
From: Marko Bencun <marko@shiftcrypto.ch>
Date: Sat, 18 Jul 2026 03:30:48 +0200
Subject: [PATCH 2/2] bump version to 0.13.0

---
 CHANGELOG-rust.md | 3 +++
 Cargo.lock        | 2 +-
 Cargo.toml        | 2 +-
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG-rust.md b/CHANGELOG-rust.md
index 3e0b446..c3775e4 100644
--- a/CHANGELOG-rust.md
+++ b/CHANGELOG-rust.md
@@ -2,6 +2,9 @@
 
 ## [Unreleased]
 
+## 0.13.0
+- Add `BitBox::from_transport()`
+
 ## 0.12.1
 - Serialize public API calls that talk to the device to avoid interleaving request/response
   sequences and breaking the device communication state.
diff --git a/Cargo.lock b/Cargo.lock
index 0c8bb7c..a4a0770 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -126,7 +126,7 @@ checksum = "32637268377fc7b10a8c6d51de3e7fba1ce5dd371a96e342b34e6078db558e7f"
 
 [[package]]
 name = "bitbox-api"
-version = "0.12.1"
+version = "0.13.0"
 dependencies = [
  "async-trait",
  "base32",
diff --git a/Cargo.toml b/Cargo.toml
index 1a88103..c4c7de3 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 name = "bitbox-api"
 authors = ["Marko Bencun <benma@bitbox.swiss>"]
-version = "0.12.1"
+version = "0.13.0"
 homepage = "https://bitbox.swiss/"
 repository = "https://github.com/BitBoxSwiss/bitbox-api-rs/"
 readme = "README-rust.md"