Use of heap feature for simpler code

.cargo/config.toml

@@ -5,5 +5,5 @@ runner = "speculos -a=1 --model=nanosp"
 target = "nanosplus"
 
 [unstable]
-build-std = ["core"]
+build-std = ["core", "alloc"]
 build-std-features = ["compiler-builtins-mem"]

Cargo.toml

@@ -1,15 +1,15 @@
 [package]
 name = "app-boilerplate-rust"
-version = "1.3.0"
+version = "1.4.0"
 authors = ["yhql", "agrojean-ledger"]
 edition = "2021"
 
 [dependencies]
-ledger_device_sdk = "1.9.2"
+ledger_device_sdk = { version="1.10.1", features = ["heap"] }
 include_gif = "1.1.0"
 serde = {version="1.0.192", default_features = false, features = ["derive"]}
 serde-json-core = { git = "https://github.com/rust-embedded-community/serde-json-core"}
-hex = { version = "0.4.3", default-features = false, features = ["serde"] }
+hex = { version = "0.4.3", default-features = false, features = ["serde", "alloc"] }
 numtoa = "0.2.4"
 
 [profile.release]
@@ -26,9 +26,6 @@ flags = "0"
 path = ["44'/1'"]
 name = "Rust Boilerplate"
 
-[package.metadata.ledger.nanos]
-icon = "crab.gif"
-
 [package.metadata.ledger.nanox]
 icon = "crab_14x14.gif"
 
@@ -39,4 +36,4 @@ icon = "crab_14x14.gif"
 icon = "crab_32x32.gif"
 
 [package.metadata.ledger.flex]
-icon = "crab_40x40.gif"
+icon = "crab_40x40.gif"

README.md

@@ -2,7 +2,9 @@
 
 ![Rule enforcer](https://github.com/LedgerHQ/app-boilerplate-rust/actions/workflows/guidelines_enforcer.yml/badge.svg) ![Build and tests](https://github.com/LedgerHQ/app-boilerplate-rust/actions/workflows/build_and_functional_tests.yml/badge.svg)
 
-This is a boilerplate application written in Rust which can be forked to start a new project for the Ledger Nano S/X/SP, Stax and Flex devices.
+This is a boilerplate application written in Rust which can be forked to start a new project for the Ledger Nano X/SP, Stax and Flex devices.
+
+:warning: Nano S is not supported
 
 * Implements standard features (display address, transaction signature...),
 * Has functional tests using [Ragger](https://github.com/LedgerHQ/ragger),
@@ -82,7 +84,7 @@ Now that you have followed the [prerequisites](#prerequisites) guide, you can bu
 cargo ledger build nanox
 ```
 
-This command will build the app for the Nano X, but you can use any supported device (`nanos`, `nanox`, `nanosplus`)
+This command will build the app for the Nano X, but you can use any supported device (`nanox`, `nanosplus`, `stax`, `flex`)
 
 ### Loading
 
@@ -94,7 +96,7 @@ This command will build the app for the Nano X, but you can use any supported de
 cargo ledger build nanox --load
 ```
 
-As for the build command, you can replace `nanos` with `nanox` or `nanosplus`.
+As for the build command, you can replace `nanox` with `nanosplus`, `stax` or `flex`.
 
 ## Test
 
@@ -111,7 +113,7 @@ pip install -r tests/requirements.txt
 * Run the functional tests :
 
 ```shell
-pytest tests/ --tb=short -v --device {nanos | nanosp | nanox}
+pytest tests/ --tb=short -v --device {nanosp | nanox | stax | flex}
 ```
 
 ### Emulator

ledger_app.toml

@@ -1,7 +1,7 @@
 [app]
 build_directory = "./"
 sdk = "Rust"
-devices = ["nanos", "nanox", "nanos+", "stax", "flex"]
+devices = ["nanox", "nanos+", "stax", "flex"]
 
 [tests]
 pytest_directory = "./tests/"

src/app_ui/address.rs

@@ -16,7 +16,7 @@
  *****************************************************************************/
 
 use crate::AppSW;
-use core::str::from_utf8_mut;
+use alloc::format;
 
 #[cfg(not(any(target_os = "stax", target_os = "flex")))]
 use ledger_device_sdk::ui::{
@@ -34,21 +34,16 @@ use include_gif::include_gif;
 const DISPLAY_ADDR_BYTES_LEN: usize = 20;
 
 pub fn ui_display_pk(addr: &[u8]) -> Result<bool, AppSW> {
- let mut addr_hex = [0u8; DISPLAY_ADDR_BYTES_LEN * 2 + 2];
- addr_hex[..2].copy_from_slice("0x".as_bytes());
- hex::encode_to_slice(
- &addr[addr.len() - DISPLAY_ADDR_BYTES_LEN..],
- &mut addr_hex[2..],
- )
- .unwrap();
- let addr_hex = from_utf8_mut(&mut addr_hex).unwrap();
- addr_hex[2..].make_ascii_uppercase();
+ let addr_hex = format!(
+ "0x{}",
+ hex::encode(&addr[addr.len() - DISPLAY_ADDR_BYTES_LEN..]).to_uppercase()
+ );
 
  #[cfg(not(any(target_os = "stax", target_os = "flex")))]
  {
  let my_field = [Field {
  name: "Address",
- value: addr_hex,
+ value: addr_hex.as_str(),
  }];
 
  let my_review = MultiFieldReview::new(
@@ -72,6 +67,6 @@ pub fn ui_display_pk(addr: &[u8]) -> Result<bool, AppSW> {
  Ok(NbglAddressReview::new()
  .glyph(&FERRIS)
  .verify_str("Verify CRAB address")
- .show(addr_hex))
+ .show(&addr_hex))
  }
 }

src/app_ui/sign.rs

@@ -15,7 +15,6 @@
  * limitations under the License.
  *****************************************************************************/
 use crate::handlers::sign_tx::Tx;
-use crate::utils::concatenate;
 use crate::AppSW;
 
 #[cfg(not(any(target_os = "stax", target_os = "flex")))]
@@ -31,9 +30,7 @@ use include_gif::include_gif;
 #[cfg(any(target_os = "stax", target_os = "flex"))]
 use ledger_device_sdk::nbgl::{Field, NbglGlyph, NbglReview};
 
-use numtoa::NumToA;
-
-const MAX_COIN_LENGTH: usize = 10;
+use alloc::format;
 
 /// Displays a transaction and returns true if user approved it.
 ///
@@ -43,31 +40,18 @@ const MAX_COIN_LENGTH: usize = 10;
 ///
 /// * `tx` - Transaction to be displayed for validation
 pub fn ui_display_tx(tx: &Tx) -> Result<bool, AppSW> {
- // Generate string for amount
- let mut numtoa_buf = [0u8; 20];
- let mut value_buf = [0u8; 20 + MAX_COIN_LENGTH + 1];
-
- let value_str = concatenate(
- &[tx.coin, " ", tx.value.numtoa_str(10, &mut numtoa_buf)],
- &mut value_buf,
- )
- .map_err(|_| AppSW::TxDisplayFail)?; // Fails if value_buf is too small
-
- // Generate destination address string in hexadecimal format.
- let mut to_str = [0u8; 42];
- to_str[..2].copy_from_slice("0x".as_bytes());
- hex::encode_to_slice(tx.to, &mut to_str[2..]).unwrap();
- to_str[2..].make_ascii_uppercase();
+ let value_str = format!("{} {}", tx.coin, tx.value);
+ let to_str = format!("0x{}", hex::encode(tx.to).to_uppercase());
 
  // Define transaction review fields
  let my_fields = [
  Field {
  name: "Amount",
- value: value_str,
+ value: value_str.as_str(),
  },
  Field {
  name: "Destination",
- value: core::str::from_utf8(&to_str).unwrap(),
+ value: to_str.as_str(),
  },
  Field {
  name: "Memo",

src/handlers/sign_tx.rs

@@ -17,6 +17,7 @@
 use crate::app_ui::sign::ui_display_tx;
 use crate::utils::Bip32Path;
 use crate::AppSW;
+use alloc::vec::Vec;
 use ledger_device_sdk::ecc::{Secp256k1, SeedDerive};
 use ledger_device_sdk::hash::{sha3::Keccak256, HashInit};
 use ledger_device_sdk::io::Comm;
@@ -38,24 +39,21 @@ pub struct Tx<'a> {
 }
 
 pub struct TxContext {
- raw_tx: [u8; MAX_TRANSACTION_LEN], // raw transaction serialized
- raw_tx_len: usize, // length of raw transaction
+ raw_tx: Vec<u8>,
  path: Bip32Path,
 }
 
 // Implement constructor for TxInfo with default values
 impl TxContext {
  pub fn new() -> TxContext {
  TxContext {
- raw_tx: [0u8; MAX_TRANSACTION_LEN],
- raw_tx_len: 0,
+ raw_tx: Vec::new(),
  path: Default::default(),
  }
  }
  // Implement reset for TxInfo
  fn reset(&mut self) {
- self.raw_tx = [0u8; MAX_TRANSACTION_LEN];
- self.raw_tx_len = 0;
+ self.raw_tx.clear();
  self.path = Default::default();
  }
 }
@@ -78,22 +76,20 @@ pub fn handler_sign_tx(
  // Next chunks, append data to raw_tx and return or parse
  // the transaction if it is the last chunk.
  } else {
- if ctx.raw_tx_len + data.len() > MAX_TRANSACTION_LEN {
+ if ctx.raw_tx.len() + data.len() > MAX_TRANSACTION_LEN {
  return Err(AppSW::TxWrongLength);
  }
 
  // Append data to raw_tx
- ctx.raw_tx[ctx.raw_tx_len..ctx.raw_tx_len + data.len()].copy_from_slice(data);
- ctx.raw_tx_len += data.len();
+ ctx.raw_tx.extend(data);
 
  // If we expect more chunks, return
  if more {
  Ok(())
  // Otherwise, try to parse the transaction
  } else {
  // Try to deserialize the transaction
- let (tx, _): (Tx, usize) =
- from_slice(&ctx.raw_tx[..ctx.raw_tx_len]).map_err(|_| AppSW::TxParsingFail)?;
+ let (tx, _): (Tx, usize) = from_slice(&ctx.raw_tx).map_err(|_| AppSW::TxParsingFail)?;
  // Display transaction. If user approves
  // the transaction, sign it. Otherwise,
  // return a "deny" status word.
@@ -110,7 +106,7 @@ fn compute_signature_and_append(comm: &mut Comm, ctx: &mut TxContext) -> Result<
  let mut keccak256 = Keccak256::new();
  let mut message_hash: [u8; 32] = [0u8; 32];
 
- let _ = keccak256.hash(&ctx.raw_tx[..ctx.raw_tx_len], &mut message_hash);
+ let _ = keccak256.hash(&ctx.raw_tx, &mut message_hash);
 
  let (sig, siglen, parity) = Secp256k1::derive_from_path(ctx.path.as_ref())
  .deterministic_sign(&message_hash)

src/main.rs

@@ -42,9 +42,12 @@ use ledger_device_sdk::io::{ApduHeader, Comm, Event, Reply, StatusWords};
 #[cfg(feature = "pending_review_screen")]
 #[cfg(not(any(target_os = "stax", target_os = "flex")))]
 use ledger_device_sdk::ui::gadgets::display_pending_review;
-#[cfg(not(any(target_os = "stax", target_os = "flex")))]
+
 ledger_device_sdk::set_panic!(ledger_device_sdk::exiting_panic);
 
+// Required for using String, Vec, format!...
+extern crate alloc;
+
 #[cfg(any(target_os = "stax", target_os = "flex"))]
 use ledger_device_sdk::nbgl::init_comm;