git.delta.rocks / unique-network / refs/commits / e137eba0a7ea

1// Copyright 2019-2022 Unique Network (Gibraltar) Ltd.2// This file is part of Unique Network.34// Unique Network is free software: you can redistribute it and/or modify5// it under the terms of the GNU General Public License as published by6// the Free Software Foundation, either version 3 of the License, or7// (at your option) any later version.89// Unique Network is distributed in the hope that it will be useful,10// but WITHOUT ANY WARRANTY; without even the implied warranty of11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the12// GNU General Public License for more details.1314// You should have received a copy of the GNU General Public License15// along with Unique Network. If not, see <http://www.gnu.org/licenses/>.1617//! Implementation of EVM RLP reader/writer1819#![allow(dead_code)]2021#[cfg(not(feature = "std"))]22use alloc::vec::Vec;23use evm_core::ExitError;24use primitive_types::{H160, U256};2526use crate::{27	execution::{Error, ResultWithPostInfo, WithPostDispatchInfo},28	types::{string, self},29};30use crate::execution::Result;3132const ABI_ALIGNMENT: usize = 32;3334/// View into RLP data, which provides method to read typed items from it35#[derive(Clone)]36pub struct AbiReader<'i> {37	buf: &'i [u8],38	subresult_offset: usize,39	offset: usize,40}41impl<'i> AbiReader<'i> {42	/// Start reading RLP buffer, assuming there is no padding bytes43	pub fn new(buf: &'i [u8]) -> Self {44		Self {45			buf,46			subresult_offset: 0,47			offset: 0,48		}49	}50	/// Start reading RLP buffer, parsing first 4 bytes as selector51	pub fn new_call(buf: &'i [u8]) -> Result<(types::bytes4, Self)> {52		if buf.len() < 4 {53			return Err(Error::Error(ExitError::OutOfOffset));54		}55		let mut method_id = [0; 4];56		method_id.copy_from_slice(&buf[0..4]);5758		Ok((59			method_id,60			Self {61				buf,62				subresult_offset: 4,63				offset: 4,64			},65		))66	}6768	fn read_pad<const S: usize>(69		buf: &[u8],70		offset: usize,71		pad_start: usize,72		pad_size: usize,73		block_start: usize,74		block_size: usize,75	) -> Result<[u8; S]> {76		if buf.len() - offset < ABI_ALIGNMENT {77			return Err(Error::Error(ExitError::OutOfOffset));78		}79		let mut block = [0; S];80		// Verify padding is empty81		if !buf[pad_start..pad_size].iter().all(|&v| v == 0) {82			return Err(Error::Error(ExitError::InvalidRange));83		}84		block.copy_from_slice(&buf[block_start..block_size]);85		Ok(block)86	}8788	fn read_padleft<const S: usize>(&mut self) -> Result<[u8; S]> {89		let offset = self.offset;90		self.offset += ABI_ALIGNMENT;91		Self::read_pad(92			self.buf,93			offset,94			offset,95			offset + ABI_ALIGNMENT - S,96			offset + ABI_ALIGNMENT - S,97			offset + ABI_ALIGNMENT,98		)99	}100101	fn read_padright<const S: usize>(&mut self) -> Result<[u8; S]> {102		let offset = self.offset;103		self.offset += ABI_ALIGNMENT;104		Self::read_pad(105			self.buf,106			offset,107			offset + S,108			offset + ABI_ALIGNMENT,109			offset,110			offset + S,111		)112	}113114	/// Read [`H160`] at current position, then advance115	pub fn address(&mut self) -> Result<H160> {116		Ok(H160(self.read_padleft()?))117	}118119	/// Read [`bool`] at current position, then advance120	pub fn bool(&mut self) -> Result<bool> {121		let data: [u8; 1] = self.read_padleft()?;122		match data[0] {123			0 => Ok(false),124			1 => Ok(true),125			_ => Err(Error::Error(ExitError::InvalidRange)),126		}127	}128129	/// Read [`[u8; 4]`] at current position, then advance130	pub fn bytes4(&mut self) -> Result<[u8; 4]> {131		self.read_padright()132	}133134	/// Read [`Vec<u8>`] at current position, then advance135	pub fn bytes(&mut self) -> Result<Vec<u8>> {136		let mut subresult = self.subresult()?;137		let length = subresult.uint32()? as usize;138		if subresult.buf.len() < subresult.offset + length {139			return Err(Error::Error(ExitError::OutOfOffset));140		}141		Ok(subresult.buf[subresult.offset..subresult.offset + length].into())142	}143144	/// Read [`string`] at current position, then advance145	pub fn string(&mut self) -> Result<string> {146		string::from_utf8(self.bytes()?).map_err(|_| Error::Error(ExitError::InvalidRange))147	}148149	/// Read [`u8`] at current position, then advance150	pub fn uint8(&mut self) -> Result<u8> {151		Ok(self.read_padleft::<1>()?[0])152	}153154	/// Read [`u32`] at current position, then advance155	pub fn uint32(&mut self) -> Result<u32> {156		Ok(u32::from_be_bytes(self.read_padleft()?))157	}158159	/// Read [`u128`] at current position, then advance160	pub fn uint128(&mut self) -> Result<u128> {161		Ok(u128::from_be_bytes(self.read_padleft()?))162	}163164	/// Read [`U256`] at current position, then advance165	pub fn uint256(&mut self) -> Result<U256> {166		let buf: [u8; 32] = self.read_padleft()?;167		Ok(U256::from_big_endian(&buf))168	}169170	/// Read [`u64`] at current position, then advance171	pub fn uint64(&mut self) -> Result<u64> {172		Ok(u64::from_be_bytes(self.read_padleft()?))173	}174175	/// Read [`usize`] at current position, then advance176	#[deprecated = "dangerous, as usize may have different width in wasm and native execution"]177	pub fn read_usize(&mut self) -> Result<usize> {178		Ok(usize::from_be_bytes(self.read_padleft()?))179	}180181	/// Slice recursive buffer, advance one word for buffer offset182	fn subresult(&mut self) -> Result<AbiReader<'i>> {183		let offset = self.uint32()? as usize;184		if offset + self.subresult_offset > self.buf.len() {185			return Err(Error::Error(ExitError::InvalidRange));186		}187		Ok(AbiReader {188			buf: self.buf,189			subresult_offset: offset + self.subresult_offset,190			offset: offset + self.subresult_offset,191		})192	}193194	/// Is this parser reached end of buffer?195	pub fn is_finished(&self) -> bool {196		self.buf.len() == self.offset197	}198}199200/// Writer for RLP encoded data201#[derive(Default)]202pub struct AbiWriter {203	static_part: Vec<u8>,204	dynamic_part: Vec<(usize, AbiWriter)>,205	had_call: bool,206}207impl AbiWriter {208	/// Initialize internal buffers for output data, assuming no padding required209	pub fn new() -> Self {210		Self::default()211	}212	/// Initialize internal buffers, inserting method selector at beginning213	pub fn new_call(method_id: u32) -> Self {214		let mut val = Self::new();215		val.static_part.extend(&method_id.to_be_bytes());216		val.had_call = true;217		val218	}219220	fn write_padleft(&mut self, block: &[u8]) {221		assert!(block.len() <= ABI_ALIGNMENT);222		self.static_part223			.extend(&[0; ABI_ALIGNMENT][0..ABI_ALIGNMENT - block.len()]);224		self.static_part.extend(block);225	}226227	fn write_padright(&mut self, bytes: &[u8]) {228		assert!(bytes.len() <= ABI_ALIGNMENT);229		self.static_part.extend(bytes);230		self.static_part231			.extend(&[0; ABI_ALIGNMENT][0..ABI_ALIGNMENT - bytes.len()]);232	}233234	/// Write [`H160`] to end of buffer235	pub fn address(&mut self, address: &H160) {236		self.write_padleft(&address.0)237	}238239	/// Write [`bool`] to end of buffer240	pub fn bool(&mut self, value: &bool) {241		self.write_padleft(&[if *value { 1 } else { 0 }])242	}243244	/// Write [`u8`] to end of buffer245	pub fn uint8(&mut self, value: &u8) {246		self.write_padleft(&[*value])247	}248249	/// Write [`u32`] to end of buffer250	pub fn uint32(&mut self, value: &u32) {251		self.write_padleft(&u32::to_be_bytes(*value))252	}253254	/// Write [`u128`] to end of buffer255	pub fn uint128(&mut self, value: &u128) {256		self.write_padleft(&u128::to_be_bytes(*value))257	}258259	/// Write [`U256`] to end of buffer260	pub fn uint256(&mut self, value: &U256) {261		let mut out = [0; 32];262		value.to_big_endian(&mut out);263		self.write_padleft(&out)264	}265266	/// Write [`usize`] to end of buffer267	#[deprecated = "dangerous, as usize may have different width in wasm and native execution"]268	pub fn write_usize(&mut self, value: &usize) {269		self.write_padleft(&usize::to_be_bytes(*value))270	}271272	/// Append recursive data, writing pending offset at end of buffer273	pub fn write_subresult(&mut self, result: Self) {274		self.dynamic_part.push((self.static_part.len(), result));275		// Empty block, to be filled later276		self.write_padleft(&[]);277	}278279	fn memory(&mut self, value: &[u8]) {280		let mut sub = Self::new();281		sub.uint32(&(value.len() as u32));282		for chunk in value.chunks(ABI_ALIGNMENT) {283			sub.write_padright(chunk);284		}285		self.write_subresult(sub);286	}287288	/// Append recursive [`str`] at end of buffer289	pub fn string(&mut self, value: &str) {290		self.memory(value.as_bytes())291	}292293	/// Append recursive [`[u8]`] at end of buffer294	pub fn bytes(&mut self, value: &[u8]) {295		self.memory(value)296	}297298	/// Finish writer, concatenating all internal buffers299	pub fn finish(mut self) -> Vec<u8> {300		for (static_offset, part) in self.dynamic_part {301			let part_offset = self.static_part.len() - self.had_call.then(|| 4).unwrap_or(0);302303			let encoded_dynamic_offset = usize::to_be_bytes(part_offset);304			self.static_part[static_offset + ABI_ALIGNMENT - encoded_dynamic_offset.len()305				..static_offset + ABI_ALIGNMENT]306				.copy_from_slice(&encoded_dynamic_offset);307			self.static_part.extend(part.finish())308		}309		self.static_part310	}311}312313/// [`AbiReader`] implements reading of many types, but it should314/// be limited to types defined in spec315///316/// As this trait can't be made sealed,317/// instead of having `impl AbiRead for T`, we have `impl AbiRead<T> for AbiReader`318pub trait AbiRead<T> {319	/// Read item from current position, advanding decoder320	fn abi_read(&mut self) -> Result<T>;321}322323macro_rules! impl_abi_readable {324	($ty:ty, $method:ident) => {325		impl AbiRead<$ty> for AbiReader<'_> {326			fn abi_read(&mut self) -> Result<$ty> {327				self.$method()328			}329		}330	};331}332333impl_abi_readable!(u8, uint8);334impl_abi_readable!(u32, uint32);335impl_abi_readable!(u64, uint64);336impl_abi_readable!(u128, uint128);337impl_abi_readable!(U256, uint256);338impl_abi_readable!([u8; 4], bytes4);339impl_abi_readable!(H160, address);340impl_abi_readable!(Vec<u8>, bytes);341impl_abi_readable!(bool, bool);342impl_abi_readable!(string, string);343344mod sealed {345	/// Not all types can be placed in vec, i.e `Vec<u8>` is restricted, `bytes` should be used instead346	pub trait CanBePlacedInVec {}347}348349impl sealed::CanBePlacedInVec for U256 {}350impl sealed::CanBePlacedInVec for string {}351impl sealed::CanBePlacedInVec for H160 {}352353impl<R: sealed::CanBePlacedInVec> AbiRead<Vec<R>> for AbiReader<'_>354where355	Self: AbiRead<R>,356{357	fn abi_read(&mut self) -> Result<Vec<R>> {358		let mut sub = self.subresult()?;359		let size = sub.uint32()? as usize;360		sub.subresult_offset = sub.offset;361		let mut out = Vec::with_capacity(size);362		for _ in 0..size {363			out.push(<Self as AbiRead<R>>::abi_read(&mut sub)?);364		}365		Ok(out)366	}367}368369macro_rules! impl_tuples {370	($($ident:ident)+) => {371		impl<$($ident),+> sealed::CanBePlacedInVec for ($($ident,)+) {}372		impl<$($ident),+> AbiRead<($($ident,)+)> for AbiReader<'_>373		where374			$(Self: AbiRead<$ident>),+375		{376			fn abi_read(&mut self) -> Result<($($ident,)+)> {377				let mut subresult = self.subresult()?;378				Ok((379					$(<Self as AbiRead<$ident>>::abi_read(&mut subresult)?,)+380				))381			}382		}383		#[allow(non_snake_case)]384		impl<$($ident),+> AbiWrite for &($($ident,)+)385		where386			$($ident: AbiWrite,)+387		{388			fn abi_write(&self, writer: &mut AbiWriter) {389				let ($($ident,)+) = self;390				$($ident.abi_write(writer);)+391			}392		}393	};394}395396impl_tuples! {A}397impl_tuples! {A B}398impl_tuples! {A B C}399impl_tuples! {A B C D}400impl_tuples! {A B C D E}401impl_tuples! {A B C D E F}402impl_tuples! {A B C D E F G}403impl_tuples! {A B C D E F G H}404impl_tuples! {A B C D E F G H I}405impl_tuples! {A B C D E F G H I J}406407/// For questions about inability to provide custom implementations,408/// see [`AbiRead`]409pub trait AbiWrite {410	/// Write value to end of specified encoder411	fn abi_write(&self, writer: &mut AbiWriter);412	/// Specialization for [`crate::solidity_interface`] implementation,413	/// see comment in `impl AbiWrite for ResultWithPostInfo`414	fn to_result(&self) -> ResultWithPostInfo<AbiWriter> {415		let mut writer = AbiWriter::new();416		self.abi_write(&mut writer);417		Ok(writer.into())418	}419}420421/// This particular AbiWrite implementation should be split to another trait,422/// which only implements `to_result`, but due to lack of specialization feature423/// in stable Rust, we can't have blanket impl of this trait `for T where T: AbiWrite`,424/// so here we abusing default trait methods for it425impl<T: AbiWrite> AbiWrite for ResultWithPostInfo<T> {426	fn abi_write(&self, _writer: &mut AbiWriter) {427		debug_assert!(false, "shouldn't be called, see comment")428	}429	fn to_result(&self) -> ResultWithPostInfo<AbiWriter> {430		match self {431			Ok(v) => Ok(WithPostDispatchInfo {432				post_info: v.post_info.clone(),433				data: {434					let mut out = AbiWriter::new();435					v.data.abi_write(&mut out);436					out437				},438			}),439			Err(e) => Err(e.clone()),440		}441	}442}443444macro_rules! impl_abi_writeable {445	($ty:ty, $method:ident) => {446		impl AbiWrite for $ty {447			fn abi_write(&self, writer: &mut AbiWriter) {448				writer.$method(&self)449			}450		}451	};452}453454impl_abi_writeable!(u8, uint8);455impl_abi_writeable!(u32, uint32);456impl_abi_writeable!(u128, uint128);457impl_abi_writeable!(U256, uint256);458impl_abi_writeable!(H160, address);459impl_abi_writeable!(bool, bool);460impl_abi_writeable!(&str, string);461impl AbiWrite for &string {462	fn abi_write(&self, writer: &mut AbiWriter) {463		writer.string(self)464	}465}466impl AbiWrite for &Vec<u8> {467	fn abi_write(&self, writer: &mut AbiWriter) {468		writer.bytes(self)469	}470}471472impl AbiWrite for () {473	fn abi_write(&self, _writer: &mut AbiWriter) {}474}475476/// Helper macros to parse reader into variables477#[deprecated]478#[macro_export]479macro_rules! abi_decode {480	($reader:expr, $($name:ident: $typ:ident),+ $(,)?) => {481		$(482			let $name = $reader.$typ()?;483		)+484	}485}486487/// Helper macros to construct RLP-encoded buffer488#[deprecated]489#[macro_export]490macro_rules! abi_encode {491	($($typ:ident($value:expr)),* $(,)?) => {{492		#[allow(unused_mut)]493		let mut writer = ::evm_coder::abi::AbiWriter::new();494		$(495			writer.$typ($value);496		)*497		writer498	}};499	(call $val:expr; $($typ:ident($value:expr)),* $(,)?) => {{500		#[allow(unused_mut)]501		let mut writer = ::evm_coder::abi::AbiWriter::new_call($val);502		$(503			writer.$typ($value);504		)*505		writer506	}}507}508509#[cfg(test)]510pub mod test {511	use crate::{512		abi::AbiRead,513		types::{string, uint256},514	};515516	use super::{AbiReader, AbiWriter};517	use hex_literal::hex;518519	#[test]520	fn dynamic_after_static() {521		let mut encoder = AbiWriter::new();522		encoder.bool(&true);523		encoder.string("test");524		let encoded = encoder.finish();525526		let mut encoder = AbiWriter::new();527		encoder.bool(&true);528		// Offset to subresult529		encoder.uint32(&(32 * 2));530		// Len of "test"531		encoder.uint32(&4);532		encoder.write_padright(&[b't', b'e', b's', b't']);533		let alternative_encoded = encoder.finish();534535		assert_eq!(encoded, alternative_encoded);536537		let mut decoder = AbiReader::new(&encoded);538		assert_eq!(decoder.bool().unwrap(), true);539		assert_eq!(decoder.string().unwrap(), "test");540	}541542	#[test]543	fn mint_sample() {544		let (call, mut decoder) = AbiReader::new_call(&hex!(545			"546				50bb4e7f547				000000000000000000000000ad2c0954693c2b5404b7e50967d3481bea432374548				0000000000000000000000000000000000000000000000000000000000000001549				0000000000000000000000000000000000000000000000000000000000000060550				0000000000000000000000000000000000000000000000000000000000000008551				5465737420555249000000000000000000000000000000000000000000000000552			"553		))554		.unwrap();555		assert_eq!(call, u32::to_be_bytes(0x50bb4e7f));556		assert_eq!(557			format!("{:?}", decoder.address().unwrap()),558			"0xad2c0954693c2b5404b7e50967d3481bea432374"559		);560		assert_eq!(decoder.uint32().unwrap(), 1);561		assert_eq!(decoder.string().unwrap(), "Test URI");562	}563564	#[test]565	fn mint_bulk() {566		let (call, mut decoder) = AbiReader::new_call(&hex!(567			"568				36543006569				00000000000000000000000053744e6da587ba10b32a2554d2efdcd985bc27a3 // address570				0000000000000000000000000000000000000000000000000000000000000040 // offset of (uint256, string)[]571				0000000000000000000000000000000000000000000000000000000000000003 // length of (uint256, string)[]572573				0000000000000000000000000000000000000000000000000000000000000060 // offset of first elem574				00000000000000000000000000000000000000000000000000000000000000e0 // offset of second elem575				0000000000000000000000000000000000000000000000000000000000000160 // offset of third elem576577				0000000000000000000000000000000000000000000000000000000000000001 // first token id?   					#60578				0000000000000000000000000000000000000000000000000000000000000040 // offset of string579				000000000000000000000000000000000000000000000000000000000000000a // size of string580				5465737420555249203000000000000000000000000000000000000000000000 // string581582				000000000000000000000000000000000000000000000000000000000000000b // second token id? Why ==11?			#e0583				0000000000000000000000000000000000000000000000000000000000000040 // offset of string584				000000000000000000000000000000000000000000000000000000000000000a // size of string585				5465737420555249203100000000000000000000000000000000000000000000 // string586587				000000000000000000000000000000000000000000000000000000000000000c // third token id?  Why ==12?			#160588				0000000000000000000000000000000000000000000000000000000000000040 // offset of string589				000000000000000000000000000000000000000000000000000000000000000a // size of string590				5465737420555249203200000000000000000000000000000000000000000000 // string591			"592		))593		.unwrap();594		assert_eq!(call, u32::to_be_bytes(0x36543006));595		let _ = decoder.address().unwrap();596		let data =597			<AbiReader<'_> as AbiRead<Vec<(uint256, string)>>>::abi_read(&mut decoder).unwrap();598		assert_eq!(599			data,600			vec![601				(1.into(), "Test URI 0".to_string()),602				(11.into(), "Test URI 1".to_string()),603				(12.into(), "Test URI 2".to_string())604			]605		);606	}607}