git.delta.rocks / unique-network / refs/commits / 2e0d1a668d33

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)]2021mod traits;22pub use traits::*;23mod impls;2425#[cfg(test)]26mod test;2728#[cfg(not(feature = "std"))]29use alloc::vec::Vec;30use evm_core::ExitError;31use primitive_types::{H160, U256};3233use crate::{34	execution::{Result, Error},35	types::*,36};3738const ABI_ALIGNMENT: usize = 32;3940/// View into RLP data, which provides method to read typed items from it41#[derive(Clone)]42pub struct AbiReader<'i> {43	buf: &'i [u8],44	subresult_offset: usize,45	offset: usize,46}47impl<'i> AbiReader<'i> {48	/// Start reading RLP buffer, assuming there is no padding bytes49	pub fn new(buf: &'i [u8]) -> Self {50		Self {51			buf,52			subresult_offset: 0,53			offset: 0,54		}55	}56	/// Start reading RLP buffer, parsing first 4 bytes as selector57	pub fn new_call(buf: &'i [u8]) -> Result<(bytes4, Self)> {58		if buf.len() < 4 {59			return Err(Error::Error(ExitError::OutOfOffset));60		}61		let mut method_id = [0; 4];62		method_id.copy_from_slice(&buf[0..4]);6364		Ok((65			method_id,66			Self {67				buf,68				subresult_offset: 4,69				offset: 4,70			},71		))72	}7374	fn read_pad<const S: usize>(75		buf: &[u8],76		offset: usize,77		pad_start: usize,78		pad_size: usize,79		block_start: usize,80		block_size: usize,81	) -> Result<[u8; S]> {82		if buf.len() - offset < ABI_ALIGNMENT {83			return Err(Error::Error(ExitError::OutOfOffset));84		}85		let mut block = [0; S];86		let is_pad_zeroed = buf[pad_start..pad_size].iter().all(|&v| v == 0);87		if !is_pad_zeroed {88			return Err(Error::Error(ExitError::InvalidRange));89		}90		block.copy_from_slice(&buf[block_start..block_size]);91		Ok(block)92	}9394	fn read_padleft<const S: usize>(&mut self) -> Result<[u8; S]> {95		let offset = self.offset;96		self.offset += ABI_ALIGNMENT;97		Self::read_pad(98			self.buf,99			offset,100			offset,101			offset + ABI_ALIGNMENT - S,102			offset + ABI_ALIGNMENT - S,103			offset + ABI_ALIGNMENT,104		)105	}106107	fn read_padright<const S: usize>(&mut self) -> Result<[u8; S]> {108		let offset = self.offset;109		self.offset += ABI_ALIGNMENT;110		Self::read_pad(111			self.buf,112			offset,113			offset + S,114			offset + ABI_ALIGNMENT,115			offset,116			offset + S,117		)118	}119120	/// Read [`H160`] at current position, then advance121	pub fn address(&mut self) -> Result<H160> {122		Ok(H160(self.read_padleft()?))123	}124125	/// Read [`bool`] at current position, then advance126	pub fn bool(&mut self) -> Result<bool> {127		let data: [u8; 1] = self.read_padleft()?;128		match data[0] {129			0 => Ok(false),130			1 => Ok(true),131			_ => Err(Error::Error(ExitError::InvalidRange)),132		}133	}134135	/// Read [`[u8; 4]`] at current position, then advance136	pub fn bytes4(&mut self) -> Result<[u8; 4]> {137		self.read_padright()138	}139140	/// Read [`Vec<u8>`] at current position, then advance141	pub fn bytes(&mut self) -> Result<Vec<u8>> {142		let mut subresult = self.subresult(None)?;143		let length = subresult.uint32()? as usize;144		if subresult.buf.len() < subresult.offset + length {145			return Err(Error::Error(ExitError::OutOfOffset));146		}147		Ok(subresult.buf[subresult.offset..subresult.offset + length].into())148	}149150	/// Read [`string`] at current position, then advance151	pub fn string(&mut self) -> Result<string> {152		string::from_utf8(self.bytes()?).map_err(|_| Error::Error(ExitError::InvalidRange))153	}154155	/// Read [`u8`] at current position, then advance156	pub fn uint8(&mut self) -> Result<u8> {157		Ok(self.read_padleft::<1>()?[0])158	}159160	/// Read [`u32`] at current position, then advance161	pub fn uint32(&mut self) -> Result<u32> {162		Ok(u32::from_be_bytes(self.read_padleft()?))163	}164165	/// Read [`u128`] at current position, then advance166	pub fn uint128(&mut self) -> Result<u128> {167		Ok(u128::from_be_bytes(self.read_padleft()?))168	}169170	/// Read [`U256`] at current position, then advance171	pub fn uint256(&mut self) -> Result<U256> {172		let buf: [u8; 32] = self.read_padleft()?;173		Ok(U256::from_big_endian(&buf))174	}175176	/// Read [`u64`] at current position, then advance177	pub fn uint64(&mut self) -> Result<u64> {178		Ok(u64::from_be_bytes(self.read_padleft()?))179	}180181	/// Read [`usize`] at current position, then advance182	#[deprecated = "dangerous, as usize may have different width in wasm and native execution"]183	pub fn read_usize(&mut self) -> Result<usize> {184		Ok(usize::from_be_bytes(self.read_padleft()?))185	}186187	/// Slice recursive buffer, advance one word for buffer offset188	/// If `size` is [`None`] then [`Self::offset`] and [`Self::subresult_offset`] evals from [`Self::buf`].189	fn subresult(&mut self, size: Option<usize>) -> Result<AbiReader<'i>> {190		let subresult_offset = self.subresult_offset;191		let offset = if let Some(size) = size {192			self.offset += size;193			self.subresult_offset += size;194			0195		} else {196			self.uint32()? as usize197		};198199		if offset + self.subresult_offset > self.buf.len() {200			return Err(Error::Error(ExitError::InvalidRange));201		}202203		let new_offset = offset + subresult_offset;204		Ok(AbiReader {205			buf: self.buf,206			subresult_offset: new_offset,207			offset: new_offset,208		})209	}210211	/// Is this parser reached end of buffer?212	pub fn is_finished(&self) -> bool {213		self.buf.len() == self.offset214	}215}216217/// Writer for RLP encoded data218#[derive(Default)]219pub struct AbiWriter {220	static_part: Vec<u8>,221	dynamic_part: Vec<(usize, AbiWriter)>,222	had_call: bool,223	is_dynamic: bool,224}225impl AbiWriter {226	/// Initialize internal buffers for output data, assuming no padding required227	pub fn new() -> Self {228		Self::default()229	}230231	/// Initialize internal buffers with data size232	pub fn new_dynamic(is_dynamic: bool) -> Self {233		Self {234			is_dynamic,235			..Default::default()236		}237	}238	/// Initialize internal buffers, inserting method selector at beginning239	pub fn new_call(method_id: u32) -> Self {240		let mut val = Self::new();241		val.static_part.extend(&method_id.to_be_bytes());242		val.had_call = true;243		val244	}245246	fn write_padleft(&mut self, block: &[u8]) {247		assert!(block.len() <= ABI_ALIGNMENT);248		self.static_part249			.extend(&[0; ABI_ALIGNMENT][0..ABI_ALIGNMENT - block.len()]);250		self.static_part.extend(block);251	}252253	fn write_padright(&mut self, block: &[u8]) {254		assert!(block.len() <= ABI_ALIGNMENT);255		self.static_part.extend(block);256		self.static_part257			.extend(&[0; ABI_ALIGNMENT][0..ABI_ALIGNMENT - block.len()]);258	}259260	/// Write [`H160`] to end of buffer261	pub fn address(&mut self, address: &H160) {262		self.write_padleft(&address.0)263	}264265	/// Write [`bool`] to end of buffer266	pub fn bool(&mut self, value: &bool) {267		self.write_padleft(&[if *value { 1 } else { 0 }])268	}269270	/// Write [`u8`] to end of buffer271	pub fn uint8(&mut self, value: &u8) {272		self.write_padleft(&[*value])273	}274275	/// Write [`u32`] to end of buffer276	pub fn uint32(&mut self, value: &u32) {277		self.write_padleft(&u32::to_be_bytes(*value))278	}279280	/// Write [`u128`] to end of buffer281	pub fn uint128(&mut self, value: &u128) {282		self.write_padleft(&u128::to_be_bytes(*value))283	}284285	/// Write [`U256`] to end of buffer286	pub fn uint256(&mut self, value: &U256) {287		let mut out = [0; 32];288		value.to_big_endian(&mut out);289		self.write_padleft(&out)290	}291292	/// Write [`usize`] to end of buffer293	#[deprecated = "dangerous, as usize may have different width in wasm and native execution"]294	pub fn write_usize(&mut self, value: &usize) {295		self.write_padleft(&usize::to_be_bytes(*value))296	}297298	/// Append recursive data, writing pending offset at end of buffer299	pub fn write_subresult(&mut self, result: Self) {300		self.dynamic_part.push((self.static_part.len(), result));301		// Empty block, to be filled later302		self.write_padleft(&[]);303	}304305	fn memory(&mut self, value: &[u8]) {306		let mut sub = Self::new();307		sub.uint32(&(value.len() as u32));308		for chunk in value.chunks(ABI_ALIGNMENT) {309			sub.write_padright(chunk);310		}311		self.write_subresult(sub);312	}313314	/// Append recursive [`str`] at end of buffer315	pub fn string(&mut self, value: &str) {316		self.memory(value.as_bytes())317	}318319	/// Append recursive [`[u8]`] at end of buffer320	pub fn bytes(&mut self, value: &[u8]) {321		self.memory(value)322	}323324	/// Finish writer, concatenating all internal buffers325	pub fn finish(mut self) -> Vec<u8> {326		for (static_offset, part) in self.dynamic_part {327			let part_offset = self.static_part.len()328				- if self.had_call { 4 } else { 0 }329				- if self.is_dynamic { ABI_ALIGNMENT } else { 0 };330331			let encoded_dynamic_offset = usize::to_be_bytes(part_offset);332			let start = static_offset + ABI_ALIGNMENT - encoded_dynamic_offset.len();333			let stop = static_offset + ABI_ALIGNMENT;334			self.static_part[start..stop].copy_from_slice(&encoded_dynamic_offset);335			self.static_part.extend(part.finish())336		}337		self.static_part338	}339}