Merge pull request #603 from devrandom/no_std_devrandom

no_std support, keeping MSRV

.github/workflows/rust.yml

@@ -13,14 +13,17 @@ jobs:
             env:
               DO_COV: true
               AS_DEPENDENCY: true
+              DO_NO_STD: true
           - rust: beta
             env:
               AS_DEPENDENCY: true
+              DO_NO_STD: true
           - rust: nightly
             env:
               DO_FUZZ: true
               DO_BENCH: true
               AS_DEPENDENCY: true
+              DO_NO_STD: true
           - rust: 1.29.0
             env:
               AS_DEPENDENCY: true
@@ -54,3 +57,24 @@ jobs:
           override: true
       - name: Create Doc
         run: cargo doc
+  Embedded:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Set up QEMU
+        run: sudo apt update && sudo apt install qemu-system-arm gcc-arm-none-eabi
+      - name: Checkout Toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          override: true
+          components: rust-src
+          target: thumbv7m-none-eabi
+      - name: Run
+        env:
+          RUSTFLAGS: "-C link-arg=-Tlink.x"
+          CARGO_TARGET_THUMBV7M_NONE_EABI_RUNNER: "qemu-system-arm -cpu cortex-m3 -machine mps2-an385 -m 1G -nographic -semihosting-config enable=on,target=native -kernel"
+        run: cd embedded && cargo run --target thumbv7m-none-eabi
+

Cargo.toml

@@ -12,7 +12,7 @@ readme = "README.md"
 
 
 [features]
-default = [ "secp-recovery" ]
+default = [ "std", "secp-recovery" ]
 base64 = [ "base64-compat" ]
 fuzztarget = []
 unstable = []
@@ -21,14 +21,24 @@ use-serde = ["serde", "bitcoin_hashes/serde", "secp256k1/serde"]
 secp-lowmemory = ["secp256k1/lowmemory"]
 secp-recovery = ["secp256k1/recovery"]
 
+# At least one of std, no-std must be enabled.
+#
+# The no-std feature doesn't disable std - you need to turn off the std feature for that by disabling default.
+# Instead no-std enables additional features required for this crate to be usable without std.
+# As a result, both can be enabled without conflict.
+std = ["secp256k1/std", "bitcoin_hashes/std", "bech32/std"]
+no-std = ["hashbrown", "core2/alloc", "bitcoin_hashes/alloc"]
+
 [dependencies]
-bech32 = "0.8.0"
-bitcoin_hashes = "0.9.6"
-secp256k1 = "0.20.2"
+bech32 = { version = "0.8.1", default-features = false }
+bitcoin_hashes = { version = "0.10.0", default-features = false }
+secp256k1 = { version = "0.20.2", default-features = false }
+core2 = { version = "0.3.0", optional = true, default-features = false }
 
 base64-compat = { version = "1.0.0", optional = true }
 bitcoinconsensus = { version = "0.19.0-3", optional = true }
 serde = { version = "1", features = [ "derive" ], optional = true }
+hashbrown = { version = "0.8", optional = true }
 
 [dev-dependencies]
 serde_json = "<1.0.45"
@@ -37,3 +47,10 @@ secp256k1 = { version = "0.20.0", features = [ "recovery", "rand-std" ] }
 bincode = "1.3.1"
 # We need to pin ryu (transitive dep from serde_json) to stay compatible with Rust 1.22.0
 ryu = "<1.0.5"
+
+[[example]]
+name = "bip32"
+
+[[example]]
+name = "handshake"
+required-features = ["std"]

contrib/test.sh

@@ -1,6 +1,12 @@
 #!/bin/sh -ex
 
-FEATURES="base64 bitcoinconsensus use-serde rand"
+FEATURES="base64 bitcoinconsensus use-serde rand secp-recovery"
+
+# Use toolchain if explicitly specified
+if [ -n "$TOOLCHAIN" ]
+then
+    alias cargo="cargo +$TOOLCHAIN"
+fi
 
 pin_common_verions() {
     cargo generate-lockfile --verbose
@@ -10,7 +16,7 @@ pin_common_verions() {
 }
 
 # Pin `cc` for Rust 1.29
-if [ -n "$PIN_VERSIONS" ]; then
+if [ "$PIN_VERSIONS" = true ]; then
     pin_common_verions
     cargo update -p byteorder --precise "1.3.4"
 fi
@@ -21,20 +27,43 @@ then
 fi
 
 
-# Use toolchain if explicitly specified
-if [ -n "$TOOLCHAIN" ]
-then
-    alias cargo="cargo +$TOOLCHAIN"
-fi
+echo "********* Testing std *************"
+# Test without any features other than std first
+cargo test --verbose --no-default-features --features="std"
 
-# Test without any features first
-cargo test --verbose --no-default-features
+echo "********* Testing default *************"
 # Then test with the default features
 cargo test --verbose
 
+if [ "$DO_NO_STD" = true ]
+then
+echo "********* Testing no-std build *************"
+  # Build no_std, to make sure that cfg(test) doesn't hide any issues
+  cargo build --verbose --features="no-std" --no-default-features
+
+  # Build std + no_std, to make sure they are not incompatible
+  cargo build --verbose --features="no-std"
+
+  # Test no_std
+  cargo test --verbose --features="no-std" --no-default-features
+
+  # Build all features
+  cargo build --verbose --features="no-std $FEATURES" --no-default-features
+
+  # Build specific features
+  for feature in ${FEATURES}
+  do
+      cargo build --verbose --features="no-std $feature"
+  done
+
+  cargo run --example bip32 L1HKVVLHXiUhecWnwFYF6L3shkf1E12HUmuZTESvBXUdx3yqVP1D
+  cargo run --no-default-features --features no-std --example bip32 L1HKVVLHXiUhecWnwFYF6L3shkf1E12HUmuZTESvBXUdx3yqVP1D
+fi
+
 # Test each feature
 for feature in ${FEATURES}
 do
+    echo "********* Testing "$feature" *************"
     cargo test --verbose --features="$feature"
 done
 
@@ -55,7 +84,7 @@ then
 fi
 
 # Use as dependency if told to
-if [ -n "$AS_DEPENDENCY" ]
+if [ "$AS_DEPENDENCY" = true ]
 then
     cargo new dep_test
     cd dep_test

embedded/Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+authors = ["Riccardo Casatta <riccardo@casatta.it>", "Dev Random <c1.devrandom@niftybox.net>"]
+edition = "2018"
+readme = "README.md"
+name = "embedded"
+version = "0.1.0"
+
+[dependencies]
+cortex-m = "0.6.0"
+cortex-m-rt = "0.6.10"
+cortex-m-semihosting = "0.3.3"
+panic-halt = "0.2.0"
+alloc-cortex-m = "0.4.1"
+bitcoin = { path="../", default-features = false, features = ["no-std", "secp-lowmemory"] }
+
+[[bin]]
+name = "embedded"
+test = false
+bench = false
+
+[profile.release]
+codegen-units = 1 # better optimizations
+debug = true # symbols are nice and they don't increase the size on Flash
+lto = true # better optimizations

embedded/README.md

@@ -0,0 +1,25 @@
+# Running
+
+To run the embedded test, first prepare your environment:
+
+```shell
+sudo ./scripts/install-deps
+rustup target add thumbv7m-none-eabi
+```
+
+Then:
+
+```shell
+source ./scripts/env.sh && cargo run --target thumbv7m-none-eabi
+```
+
+Output should be something like:
+
+```text
+heap size 524288
+secp buf size 66240
+Seed WIF: L1HKVVLHXiUhecWnwFYF6L3shkf1E12HUmuZTESvBXUdx3yqVP1D
+Address: bc1qpx9t9pzzl4qsydmhyt6ctrxxjd4ep549np9993
+```
+
+Note that this heap size is required because of the amount of stack used by libsecp256k1 when initializing a context.

embedded/memory.x

@@ -0,0 +1,5 @@
+MEMORY
+{
+  FLASH : ORIGIN = 0x00000000, LENGTH = 512K
+  RAM : ORIGIN = 0x20000000, LENGTH = 512K
+}

embedded/scripts/env.sh

@@ -0,0 +1,2 @@
+export RUSTFLAGS="-C link-arg=-Tlink.x"
+export CARGO_TARGET_THUMBV7M_NONE_EABI_RUNNER="qemu-system-arm -cpu cortex-m3 -machine mps2-an385 -m 1G -nographic -semihosting-config enable=on,target=native -kernel"

embedded/scripts/install-deps

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+apt install gcc-arm-none-eabi qemu-system-arm gdb-multiarch

embedded/src/main.rs

@@ -0,0 +1,76 @@
+#![feature(alloc_error_handler)]
+#![feature(panic_info_message)]
+#![no_std]
+#![no_main]
+
+extern crate alloc;
+extern crate bitcoin;
+
+use alloc::string::ToString;
+use alloc::vec;
+use core::alloc::Layout;
+use core::panic::PanicInfo;
+
+use alloc_cortex_m::CortexMHeap;
+// use panic_halt as _;
+use bitcoin::{Address, Network, PrivateKey};
+use bitcoin::secp256k1::ffi::types::AlignedType;
+use bitcoin::secp256k1::Secp256k1;
+
+use cortex_m::asm;
+use cortex_m_rt::entry;
+use cortex_m_semihosting::{debug, hprintln};
+
+// this is the allocator the application will use
+#[global_allocator]
+static ALLOCATOR: CortexMHeap = CortexMHeap::empty();
+
+const HEAP_SIZE: usize = 1024 * 512; // 512 KB
+
+#[entry]
+fn main() -> ! {
+    hprintln!("heap size {}", HEAP_SIZE).unwrap();
+
+    unsafe { ALLOCATOR.init(cortex_m_rt::heap_start() as usize, HEAP_SIZE) }
+
+    let size = Secp256k1::preallocate_size();
+    hprintln!("secp buf size {}", size*16).unwrap();
+
+    // Load a private key
+    let raw = "L1HKVVLHXiUhecWnwFYF6L3shkf1E12HUmuZTESvBXUdx3yqVP1D";
+    let pk = PrivateKey::from_wif(raw).unwrap();
+    hprintln!("Seed WIF: {}", pk).unwrap();
+
+    let mut buf_ful = vec![AlignedType::zeroed(); size];
+    let secp = Secp256k1::preallocated_new(&mut buf_ful).unwrap();
+
+    // Derive address
+    let pubkey = pk.public_key(&secp);
+    let address = Address::p2wpkh(&pubkey, Network::Bitcoin).unwrap();
+    hprintln!("Address: {}", address).unwrap();
+
+    assert_eq!(address.to_string(), "bc1qpx9t9pzzl4qsydmhyt6ctrxxjd4ep549np9993".to_string());
+    // exit QEMU
+    // NOTE do not run this on hardware; it can corrupt OpenOCD state
+    debug::exit(debug::EXIT_SUCCESS);
+
+    loop {}
+}
+
+// define what happens in an Out Of Memory (OOM) condition
+#[alloc_error_handler]
+fn alloc_error(_layout: Layout) -> ! {
+    hprintln!("alloc error").unwrap();
+    debug::exit(debug::EXIT_FAILURE);
+    asm::bkpt();
+
+    loop {}
+}
+
+#[inline(never)]
+#[panic_handler]
+fn panic(info: &PanicInfo) -> ! {
+    hprintln!("panic {:?}", info.message()).unwrap();
+    debug::exit(debug::EXIT_FAILURE);
+    loop {}
+}

examples/bip32.rs

@@ -10,6 +10,7 @@ use bitcoin::util::bip32::ExtendedPubKey;
 use bitcoin::util::bip32::DerivationPath;
 use bitcoin::util::bip32::ChildNumber;
 use bitcoin::util::address::Address;
+use bitcoin::secp256k1::ffi::types::AlignedType;
 
 fn main() {
     // This example derives root xprv
@@ -36,7 +37,9 @@ fn main() {
     let seed = wif.to_bytes();
 
     // we need secp256k1 context for key derivation
-    let secp = Secp256k1::new();
+    let mut buf: Vec<AlignedType> = Vec::new();
+    buf.resize(Secp256k1::preallocate_size(), AlignedType::zeroed());
+    let secp = Secp256k1::preallocated_new(buf.as_mut_slice()).unwrap();
 
     // calculate root key from seed
     let root = ExtendedPrivKey::new_master(network, &seed).unwrap();

src/blockdata/block.rs

@@ -20,6 +20,8 @@
 //! these blocks and the blockchain.
 //!
 
+use prelude::*;
+
 use core::fmt;
 
 use util;
@@ -308,6 +310,7 @@ impl fmt::Display for Bip34Error {
     }
 }
 
+#[cfg(feature = "std")]
 impl ::std::error::Error for Bip34Error {}
 
 #[cfg(test)]

src/blockdata/constants.rs

@@ -19,9 +19,11 @@
 //! single transaction
 //!
 
+use prelude::*;
+
 use core::default::Default;
 
-use hashes::hex::FromHex;
+use hashes::hex::{HexIterator, Error as HexError};
 use hashes::sha256d;
 use blockdata::opcodes;
 use blockdata::script;
@@ -84,8 +86,11 @@ fn bitcoin_genesis_tx() -> Transaction {
     });
 
     // Outputs
+    let script_bytes: Result<Vec<u8>, HexError> =
+        HexIterator::new("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f").unwrap()
+            .collect();
     let out_script = script::Builder::new()
-        .push_slice(&Vec::from_hex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f").unwrap())
+        .push_slice(script_bytes.unwrap().as_slice())
         .push_opcode(opcodes::all::OP_CHECKSIG)
         .into_script();
     ret.output.push(TxOut {

src/blockdata/opcodes.rs

@@ -22,6 +22,8 @@
 
 #[cfg(feature = "serde")] use serde;
 
+#[cfg(feature = "serde")] use prelude::*;
+
 use core::{fmt, convert::From};
 
 // Note: I am deliberately not implementing PartialOrd or Ord on the