ethereum.forks.bpo1.vm.precompiled_contracts.ripemd160

Ethereum Virtual Machine (EVM) RIPEMD160 PRECOMPILED CONTRACT.

.. contents:: Table of Contents :backlinks: none :local:

Introduction

Implementation of the RIPEMD160 precompiled contract.

ripemd160

Writes the ripemd160 hash to output.

Parameters

evm : The current EVM frame.

def ripemd160(​evm: Evm​) -> None:
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    """
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    Writes the ripemd160 hash to output.
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    Parameters
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    ----------
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    evm :
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        The current EVM frame.
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    """
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    data = evm.message.data
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    # GAS
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    word_count = ceil32(Uint(len(data))) // Uint(32)
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    charge_gas(
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        evm,
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        GAS_PRECOMPILE_RIPEMD160_BASE
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        + GAS_PRECOMPILE_RIPEMD160_PER_WORD * word_count,
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    )
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    # OPERATION
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    hash_bytes = hashlib.new("ripemd160", data).digest()
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    padded_hash = left_pad_zero_bytes(hash_bytes, 32)
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    evm.output = padded_hash