Add a lightning-wasm-bindings crate and generation code 2021-01-wasm-bindings
authorMatt Corallo <git@bluematt.me>
Tue, 5 Jan 2021 19:03:44 +0000 (14:03 -0500)
committerMatt Corallo <git@bluematt.me>
Tue, 5 Jan 2021 19:03:44 +0000 (14:03 -0500)
genbindings.sh
lightning-wasm-bindings/Cargo.toml [new file with mode: 0644]
lightning-wasm-bindings/src/bitcoin/mod.rs [new file with mode: 0644]
lightning-wasm-bindings/src/bitcoin/network.rs [new file with mode: 0644]
lightning-wasm-bindings/src/c_types/mod.rs [new file with mode: 0644]

index da8a1c15a5c06e9fd1b39772eb9899e5fe0cc0d2..8ff8861961cf6030798cbf94695a7847a0d26b53 100755 (executable)
@@ -8,24 +8,40 @@ set -x
 # First build the latest c-bindings-gen binary
 cd c-bindings-gen && cargo build && cd ..
 
-# Then wipe all the existing C bindings (because we're being run in the right directory)
-# note that we keep the few manually-generated files first:
-mv lightning-c-bindings/src/c_types/mod.rs ./
-mv lightning-c-bindings/src/bitcoin ./
-
-rm -rf lightning-c-bindings/src
-
-mkdir -p lightning-c-bindings/src/c_types/
-mv ./mod.rs lightning-c-bindings/src/c_types/
-mv ./bitcoin lightning-c-bindings/src/
-
-# Finally, run the c-bindings-gen binary, building fresh bindings.
-SRC="$(pwd)/lightning/src"
-OUT="$(pwd)/lightning-c-bindings/src"
-OUT_TEMPL="$(pwd)/lightning-c-bindings/src/c_types/derived.rs"
-OUT_F="$(pwd)/lightning-c-bindings/include/rust_types.h"
-OUT_CPP="$(pwd)/lightning-c-bindings/include/lightningpp.hpp"
-RUST_BACKTRACE=1 ./c-bindings-gen/target/debug/c-bindings-gen $SRC/ $OUT/ lightning $OUT_TEMPL $OUT_F $OUT_CPP "#[no_mangle]" "#[repr(C)]"
+for FOLDER in "lightning-c-bindings" "lightning-wasm-bindings"; do
+       # Then wipe all the existing C bindings (because we're being run in the right directory)
+       # note that we keep the few manually-generated files first:
+       mv $FOLDER/src/c_types/mod.rs ./
+       mv $FOLDER/src/bitcoin ./
+
+       rm -rf $FOLDER/src
+
+       mkdir -p $FOLDER/src/c_types/
+       mv ./mod.rs $FOLDER/src/c_types/
+       mv ./bitcoin $FOLDER/src/
+
+       # Finally, run the c-bindings-gen binary, building fresh bindings.
+       SRC="$(pwd)/lightning/src"
+       OUT="$(pwd)/$FOLDER/src"
+       OUT_TEMPL="$(pwd)/$FOLDER/src/c_types/derived.rs"
+       if [ "$FOLDER" = "lightning-c-bindings" ]; then
+               OUT_F="$(pwd)/$FOLDER/include/rust_types.h"
+               OUT_CPP="$(pwd)/$FOLDER/include/lightningpp.hpp"
+               FN_ATTR="#[no_mangle]"
+               STRUCT_ATTR="#[repr(C)]"
+       else
+               # WASM bindings don't care about C++ headers
+               OUT_F="/dev/null"
+               OUT_CPP="/dev/null"
+               FN_ATTR="#[wasm_bindgen::prelude::wasm_bindgen]"
+               STRUCT_ATTR="#[wasm_bindgen::prelude::wasm_bindgen]"
+       fi
+       RUST_BACKTRACE=1 ./c-bindings-gen/target/debug/c-bindings-gen $SRC/ $OUT/ lightning $OUT_TEMPL $OUT_F $OUT_CPP "$FN_ATTR" "$STRUCT_ATTR"
+
+       pushd $FOLDER
+       cargo build
+       popd
+done
 
 # Now cd to lightning-c-bindings, build the generated bindings, and call cbindgen to build a C header file
 PATH="$PATH:~/.cargo/bin"
diff --git a/lightning-wasm-bindings/Cargo.toml b/lightning-wasm-bindings/Cargo.toml
new file mode 100644 (file)
index 0000000..093ef0c
--- /dev/null
@@ -0,0 +1,23 @@
+[package]
+name = "lightning-wasm-bindings"
+version = "0.0.1"
+authors = ["Matt Corallo"]
+license = "Apache-2.0"
+edition = "2018"
+description = """
+Utilities to fetch the chain from Bitcoin Core REST/RPC Interfaces and feed them into Rust Lightning.
+"""
+
+[lib]
+name = "ldk"
+crate-type = ["cdylib"]
+
+[dependencies]
+bitcoin = "0.24"
+lightning = { version = "0.0.12", path = "../lightning" }
+wasm-bindgen = "0.2"
+
+# We eventually want to join the root workspace, but for now, the bindings generation is
+# a bit brittle and we don't want to hold up other developers from making changes just
+# because they break the bindings
+[workspace]
diff --git a/lightning-wasm-bindings/src/bitcoin/mod.rs b/lightning-wasm-bindings/src/bitcoin/mod.rs
new file mode 100644 (file)
index 0000000..a61610b
--- /dev/null
@@ -0,0 +1 @@
+pub mod network;
diff --git a/lightning-wasm-bindings/src/bitcoin/network.rs b/lightning-wasm-bindings/src/bitcoin/network.rs
new file mode 100644 (file)
index 0000000..13799c0
--- /dev/null
@@ -0,0 +1,18 @@
+use bitcoin::network::constants::Network as BitcoinNetwork;
+
+#[repr(C)]
+pub enum Network {
+       Bitcoin,
+       Testnet,
+       Regtest,
+}
+
+impl Network {
+       pub(crate) fn into_bitcoin(&self) -> BitcoinNetwork {
+               match self {
+                       Network::Bitcoin => BitcoinNetwork::Bitcoin,
+                       Network::Testnet => BitcoinNetwork::Testnet,
+                       Network::Regtest => BitcoinNetwork::Regtest,
+               }
+       }
+}
diff --git a/lightning-wasm-bindings/src/c_types/mod.rs b/lightning-wasm-bindings/src/c_types/mod.rs
new file mode 100644 (file)
index 0000000..4e032a0
--- /dev/null
@@ -0,0 +1,315 @@
+pub mod derived;
+
+use bitcoin::Script as BitcoinScript;
+use bitcoin::Transaction as BitcoinTransaction;
+use bitcoin::hashes::Hash;
+use bitcoin::secp256k1::key::PublicKey as SecpPublicKey;
+use bitcoin::secp256k1::key::SecretKey as SecpSecretKey;
+use bitcoin::secp256k1::Signature as SecpSignature;
+use bitcoin::secp256k1::Error as SecpError;
+
+use std::convert::TryInto; // Bindings need at least rustc 1.34
+
+use wasm_bindgen::prelude::wasm_bindgen;
+
+#[wasm_bindgen]
+#[derive(Clone)]
+pub struct PublicKey {
+       pub compressed_form: [u8; 33],
+}
+impl PublicKey {
+       pub(crate) fn from_rust(pk: &SecpPublicKey) -> Self {
+               Self {
+                       compressed_form: pk.serialize(),
+               }
+       }
+       pub(crate) fn into_rust(&self) -> SecpPublicKey {
+               SecpPublicKey::from_slice(&self.compressed_form).unwrap()
+       }
+       pub(crate) fn is_null(&self) -> bool { self.compressed_form[..] == [0; 33][..] }
+       pub(crate) fn null() -> Self { Self { compressed_form: [0; 33] } }
+}
+
+#[wasm_bindgen]
+pub struct SecretKey {
+       pub bytes: [u8; 32],
+}
+impl SecretKey {
+       // from_rust isn't implemented for a ref since we just return byte array refs directly
+       pub(crate) fn from_rust(sk: SecpSecretKey) -> Self {
+               let mut bytes = [0; 32];
+               bytes.copy_from_slice(&sk[..]);
+               Self { bytes }
+       }
+       pub(crate) fn into_rust(&self) -> SecpSecretKey {
+               SecpSecretKey::from_slice(&self.bytes).unwrap()
+       }
+}
+
+#[wasm_bindgen]
+pub struct Signature {
+       pub compact_form: [u8; 64],
+}
+impl Signature {
+       pub(crate) fn from_rust(pk: &SecpSignature) -> Self {
+               Self {
+                       compact_form: pk.serialize_compact(),
+               }
+       }
+       pub(crate) fn into_rust(&self) -> SecpSignature {
+               SecpSignature::from_compact(&self.compact_form).unwrap()
+       }
+       // The following are used for Option<Signature> which we support, but don't use anymore
+       #[allow(unused)] pub(crate) fn is_null(&self) -> bool { self.compact_form[..] == [0; 64][..] }
+       #[allow(unused)] pub(crate) fn null() -> Self { Self { compact_form: [0; 64] } }
+}
+
+#[wasm_bindgen]
+pub enum Secp256k1Error {
+       IncorrectSignature,
+       InvalidMessage,
+       InvalidPublicKey,
+       InvalidSignature,
+       InvalidSecretKey,
+       InvalidRecoveryId,
+       InvalidTweak,
+       NotEnoughMemory,
+       CallbackPanicked,
+}
+impl Secp256k1Error {
+       pub(crate) fn from_rust(err: SecpError) -> Self {
+               match err {
+                       SecpError::IncorrectSignature => Secp256k1Error::IncorrectSignature,
+                       SecpError::InvalidMessage => Secp256k1Error::InvalidMessage,
+                       SecpError::InvalidPublicKey => Secp256k1Error::InvalidPublicKey,
+                       SecpError::InvalidSignature => Secp256k1Error::InvalidSignature,
+                       SecpError::InvalidSecretKey => Secp256k1Error::InvalidSecretKey,
+                       SecpError::InvalidRecoveryId => Secp256k1Error::InvalidRecoveryId,
+                       SecpError::InvalidTweak => Secp256k1Error::InvalidTweak,
+                       SecpError::NotEnoughMemory => Secp256k1Error::NotEnoughMemory,
+               }
+       }
+}
+
+#[wasm_bindgen]
+/// A serialized transaction, in (pointer, length) form.
+///
+/// This type optionally owns its own memory, and thus the semantics around access change based on
+/// the `data_is_owned` flag. If `data_is_owned` is set, you must call `Transaction_free` to free
+/// the underlying buffer before the object goes out of scope. If `data_is_owned` is not set, any
+/// access to the buffer after the scope in which the object was provided to you is invalid. eg,
+/// access after you return from the call in which a `!data_is_owned` `Transaction` is provided to
+/// you would be invalid.
+///
+/// Note that, while it may change in the future, because transactions on the Rust side are stored
+/// in a deserialized form, all `Transaction`s generated on the Rust side will have `data_is_owned`
+/// set. Similarly, while it may change in the future, all `Transaction`s you pass to Rust may have
+/// `data_is_owned` either set or unset at your discretion.
+pub struct Transaction {
+       /// This is non-const for your convenience, an object passed to Rust is never written to.
+       pub data: *mut u8,
+       pub datalen: usize,
+       pub data_is_owned: bool,
+}
+impl Transaction {
+       pub(crate) fn into_bitcoin(&self) -> BitcoinTransaction {
+               if self.datalen == 0 { panic!("0-length buffer can never represent a valid Transaction"); }
+               ::bitcoin::consensus::encode::deserialize(unsafe { std::slice::from_raw_parts(self.data, self.datalen) }).unwrap()
+       }
+       pub(crate) fn from_vec(v: Vec<u8>) -> Self {
+               let datalen = v.len();
+               let data = Box::into_raw(v.into_boxed_slice());
+               Self {
+                       data: unsafe { (*data).as_mut_ptr() },
+                       datalen,
+                       data_is_owned: true,
+               }
+       }
+}
+impl Drop for Transaction {
+       fn drop(&mut self) {
+               if self.data_is_owned && self.datalen != 0 {
+                       let _ = derived::CVec_u8Z { data: self.data as *mut u8, datalen: self.datalen };
+               }
+       }
+}
+#[no_mangle]
+pub extern "C" fn Transaction_free(_res: Transaction) { }
+
+pub(crate) fn bitcoin_to_C_outpoint(outpoint: ::bitcoin::blockdata::transaction::OutPoint) -> crate::chain::transaction::OutPoint {
+       crate::chain::transaction::OutPoint_new(ThirtyTwoBytes { data: outpoint.txid.into_inner() }, outpoint.vout.try_into().unwrap())
+}
+
+#[wasm_bindgen]
+#[derive(Clone)]
+/// A transaction output including a scriptPubKey and value.
+/// This type *does* own its own memory, so must be free'd appropriately.
+pub struct TxOut {
+       pub script_pubkey: derived::CVec_u8Z,
+       pub value: u64,
+}
+
+impl TxOut {
+       pub(crate) fn into_rust(mut self) -> ::bitcoin::blockdata::transaction::TxOut {
+               ::bitcoin::blockdata::transaction::TxOut {
+                       script_pubkey: self.script_pubkey.into_rust().into(),
+                       value: self.value,
+               }
+       }
+       pub(crate) fn from_rust(txout: ::bitcoin::blockdata::transaction::TxOut) -> Self {
+               Self {
+                       script_pubkey: derived::CVec_u8Z::from(txout.script_pubkey.into_bytes()),
+                       value: txout.value
+               }
+       }
+}
+#[no_mangle]
+pub extern "C" fn TxOut_free(_res: TxOut) { }
+
+#[wasm_bindgen]
+pub struct u8slice {
+       pub data: *const u8,
+       pub datalen: usize
+}
+impl u8slice {
+       pub(crate) fn from_slice(s: &[u8]) -> Self {
+               Self {
+                       data: s.as_ptr(),
+                       datalen: s.len(),
+               }
+       }
+       pub(crate) fn to_slice(&self) -> &[u8] {
+               if self.datalen == 0 { return &[]; }
+               unsafe { std::slice::from_raw_parts(self.data, self.datalen) }
+       }
+}
+
+#[wasm_bindgen]
+#[derive(Copy, Clone)]
+/// Arbitrary 32 bytes, which could represent one of a few different things. You probably want to
+/// look up the corresponding function in rust-lightning's docs.
+pub struct ThirtyTwoBytes {
+       pub data: [u8; 32],
+}
+impl ThirtyTwoBytes {
+       pub(crate) fn null() -> Self {
+               Self { data: [0; 32] }
+       }
+}
+
+#[wasm_bindgen]
+pub struct ThreeBytes { pub data: [u8; 3], }
+#[wasm_bindgen]
+#[derive(Clone)]
+pub struct FourBytes { pub data: [u8; 4], }
+#[wasm_bindgen]
+#[derive(Clone)]
+pub struct TenBytes { pub data: [u8; 10], }
+#[wasm_bindgen]
+#[derive(Clone)]
+pub struct SixteenBytes { pub data: [u8; 16], }
+
+pub(crate) struct VecWriter(pub Vec<u8>);
+impl lightning::util::ser::Writer for VecWriter {
+       fn write_all(&mut self, buf: &[u8]) -> Result<(), ::std::io::Error> {
+               self.0.extend_from_slice(buf);
+               Ok(())
+       }
+       fn size_hint(&mut self, size: usize) {
+               self.0.reserve_exact(size);
+       }
+}
+pub(crate) fn serialize_obj<I: lightning::util::ser::Writeable>(i: &I) -> derived::CVec_u8Z {
+       let mut out = VecWriter(Vec::new());
+       i.write(&mut out).unwrap();
+       derived::CVec_u8Z::from(out.0)
+}
+pub(crate) fn deserialize_obj<I: lightning::util::ser::Readable>(s: u8slice) -> Result<I, lightning::ln::msgs::DecodeError> {
+       I::read(&mut s.to_slice())
+}
+pub(crate) fn deserialize_obj_arg<A, I: lightning::util::ser::ReadableArgs<A>>(s: u8slice, args: A) -> Result<I, lightning::ln::msgs::DecodeError> {
+       I::read(&mut s.to_slice(), args)
+}
+
+#[wasm_bindgen]
+#[derive(Copy, Clone)]
+/// A Rust str object, ie a reference to a UTF8-valid string.
+/// This is *not* null-terminated so cannot be used directly as a C string!
+pub struct Str {
+       pub chars: *const u8,
+       pub len: usize
+}
+impl Into<Str> for &'static str {
+       fn into(self) -> Str {
+               Str { chars: self.as_ptr(), len: self.len() }
+       }
+}
+impl Into<&'static str> for Str {
+       fn into(self) -> &'static str {
+               if self.len == 0 { return ""; }
+               std::str::from_utf8(unsafe { std::slice::from_raw_parts(self.chars, self.len) }).unwrap()
+       }
+}
+
+// Note that the C++ headers memset(0) all the Templ types to avoid deallocation!
+// Thus, they must gracefully handle being completely null in _free.
+
+// TODO: Integer/bool primitives should avoid the pointer indirection for underlying types
+// everywhere in the containers.
+
+pub union CResultPtr<O, E> {
+       pub result: *mut O,
+       pub err: *mut E,
+}
+pub struct CResultTempl<O, E> {
+       pub contents: CResultPtr<O, E>,
+       pub result_ok: bool,
+}
+impl<O, E> CResultTempl<O, E> {
+       pub(crate) extern "C" fn ok(o: O) -> Self {
+               CResultTempl {
+                       contents: CResultPtr {
+                               result: Box::into_raw(Box::new(o)),
+                       },
+                       result_ok: true,
+               }
+       }
+       pub(crate) extern "C" fn err(e: E) -> Self {
+               CResultTempl {
+                       contents: CResultPtr {
+                               err: Box::into_raw(Box::new(e)),
+                       },
+                       result_ok: false,
+               }
+       }
+}
+impl<O, E> Drop for CResultTempl<O, E> {
+       fn drop(&mut self) {
+               if self.result_ok {
+                       if unsafe { !self.contents.result.is_null() } {
+                               unsafe { Box::from_raw(self.contents.result) };
+                       }
+               } else if unsafe { !self.contents.err.is_null() } {
+                       unsafe { Box::from_raw(self.contents.err) };
+               }
+       }
+}
+
+/// Utility to make it easy to set a pointer to null and get its original value in line.
+pub(crate) trait TakePointer<T> {
+       fn take_ptr(&mut self) -> T;
+}
+impl<T> TakePointer<*const T> for *const T {
+       fn take_ptr(&mut self) -> *const T {
+               let ret = *self;
+               *self = std::ptr::null();
+               ret
+       }
+}
+impl<T> TakePointer<*mut T> for *mut T {
+       fn take_ptr(&mut self) -> *mut T {
+               let ret = *self;
+               *self = std::ptr::null_mut();
+               ret
+       }
+}