Inspiration

What it does

Running ethereum bytecode in eosio smart contract

How I built it

There are two related repositories:

https://github.com/learnforpractice/eos-with-evm

https://github.com/learnforpractice/evm4eosio

The source code in evm4eosio/evm4eos will used to generate a wasm file named ethereum_vm.wasm that can be deploy to a eosio based network.

The same source code in evm4eosio/evm4eos will also generate a shared library named evm4eos which will used to implement intrinsic functions.

The source code have three API functions:

int evm_execute(const char *raw_trx, size_t raw_trx_size, const char *sender_address, size_t sender_address_size);

int evm_get_account_id(uint64_t account, const char* arbitrary_string, size_t arbitrary_string_size, char* hash, size_t hash_size);

int evm_recover_key(const uint8_t* _sig, uint32_t _sig_size, const uint8_t* _message, uint32_t _message_len, uint8_t* _serialized_public_key, uint32_t _serialized_public_key_size);

evm_execute and evm_get_account_id implemented in evm4eosio/evm4eos/main.cpp

evm_recover_key implemented in evm4eosio/libdevcrypto/Common.cpp

These functions can be configured to implemented as intrinsic functions which can be called by wasm code or compile directly in WASM bytecode with the following cmake variables to improve performance.

USE_INTRINSIC_EVM_EXECUTE

USE_INTRINSIC_EVM_GET_ACCOUNT_ID

USE_INTRINSIC_EVM_RECOVER_KEY

The source code of https://github.com/learnforpractice/eos-with-evm is a fork of eosio source code that have the above three intrinsic function implemented.

Challenges I ran into

Compile EVM source code to WASM

Accomplishments that I'm proud of

Abstracting vm api functions from eosio which allow compile C++ smart contract to native code without changes.

What I learned

Security > Usability > Maintainability > Simplicity > Performance

What's next for evm4eos

Bug Fixes & Continue to improve evm performance and some other things.

Built With

• aleth
• boost
• eosio
• ethash
• secp256k1