nimbus-eth1/nimbus/evm/precompiles.nim

766 lines
22 KiB
Nim

# Nimbus
# Copyright (c) 2018-2024 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
# http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or
# http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed except
# according to those terms.
import
std/[macros],
results,
"."/[types, blake2b_f, blscurve],
./interpreter/[gas_meter, gas_costs, utils/utils_numeric],
eth/[common, keys],
chronicles,
nimcrypto/[ripemd, sha2, utils],
bncurve/[fields, groups],
stew/assign2,
../common/evmforks,
../core/eip4844,
./modexp,
./evm_errors,
./computation
type
PrecompileAddresses* = enum
# Frontier to Spurious Dragron
paEcRecover = 0x01,
paSha256 = 0x02,
paRipeMd160 = 0x03,
paIdentity = 0x04,
# Byzantium and Constantinople
paModExp = 0x05,
paEcAdd = 0x06,
paEcMul = 0x07,
paPairing = 0x08,
# Istanbul
paBlake2bf = 0x09,
# Cancun
paPointEvaluation = 0x0A,
# Prague (EIP-2537)
paBlsG1Add = 0x0b,
paBlsG1Mul = 0x0c,
paBlsG1MultiExp = 0x0d,
paBlsG2Add = 0x0e,
paBlsG2Mul = 0x0f,
paBlsG2MultiExp = 0x10,
paBlsPairing = 0x11,
paBlsMapG1 = 0x12,
paBlsMapG2 = 0x13
SigRes = object
msgHash: array[32, byte]
sig: Signature
# ------------------------------------------------------------------------------
# Private functions
# ------------------------------------------------------------------------------
func getMaxPrecompileAddr(fork: EVMFork): PrecompileAddresses =
if fork < FkByzantium: paIdentity
elif fork < FkIstanbul: paPairing
elif fork < FkCancun: paBlake2bf
elif fork < FkPrague: paPointEvaluation
else: PrecompileAddresses.high
func validPrecompileAddr(addrByte, maxPrecompileAddr: byte): bool =
(addrByte in PrecompileAddresses.low.byte .. maxPrecompileAddr)
func validPrecompileAddr(addrByte: byte, fork: EVMFork): bool =
let maxPrecompileAddr = getMaxPrecompileAddr(fork)
validPrecompileAddr(addrByte, maxPrecompileAddr.byte)
func getSignature(c: Computation): EvmResult[SigRes] =
# input is Hash, V, R, S
template data: untyped = c.msg.data
var bytes: array[65, byte] # will hold R[32], S[32], V[1], in that order
let maxPos = min(data.high, 127)
# if we don't have at minimum 64 bytes, there can be no valid V
if maxPos < 63:
return err(prcErr(PrcInvalidSig))
let v = data[63]
# check if V[32] is 27 or 28
if not (v.int in 27..28):
return err(prcErr(PrcInvalidSig))
for x in 32..<63:
if data[x] != 0:
return err(prcErr(PrcInvalidSig))
bytes[64] = v - 27
# if there is more data for R and S, copy it. Else, defaulted zeroes are
# used for R and S
if maxPos >= 64:
# Copy message data to buffer
bytes[0..(maxPos-64)] = data[64..maxPos]
let sig = Signature.fromRaw(bytes).valueOr:
return err(prcErr(PrcInvalidSig))
var res = SigRes(sig: sig)
# extract message hash, only need to copy when there is a valid signature
assign(res.msgHash, data.toOpenArray(0, 31))
ok(res)
func simpleDecode(dst: var FQ2, src: openArray[byte]): bool {.noinit.} =
# bypassing FQ2.fromBytes
# because we want to check `value > modulus`
result = false
if dst.c1.fromBytes(src.toOpenArray(0, 31)) and
dst.c0.fromBytes(src.toOpenArray(32, 63)):
result = true
template simpleDecode(dst: var FQ, src: openArray[byte]): bool =
fromBytes(dst, src)
func getPoint[T: G1|G2](_: typedesc[T], data: openArray[byte]): EvmResult[Point[T]] =
when T is G1:
const nextOffset = 32
var px, py: FQ
else:
const nextOffset = 64
var px, py: FQ2
if not px.simpleDecode(data.toOpenArray(0, nextOffset - 1)):
return err(prcErr(PrcInvalidPoint))
if not py.simpleDecode(data.toOpenArray(nextOffset, nextOffset * 2 - 1)):
return err(prcErr(PrcInvalidPoint))
if px.isZero() and py.isZero():
ok(T.zero())
else:
var ap: AffinePoint[T]
if not ap.init(px, py):
return err(prcErr(PrcInvalidPoint))
ok(ap.toJacobian())
func getFR(data: openArray[byte]): EvmResult[FR] =
var res: FR
if not res.fromBytes2(data):
return err(prcErr(PrcInvalidPoint))
ok(res)
# ------------------------------------------------------------------------------
# Precompiles functions
# ------------------------------------------------------------------------------
func ecRecover(c: Computation): EvmResultVoid =
? c.gasMeter.consumeGas(
GasECRecover,
reason="ECRecover Precompile")
let
sig = ? c.getSignature()
pubkey = recover(sig.sig, SkMessage(sig.msgHash)).valueOr:
return err(prcErr(PrcInvalidSig))
c.output.setLen(32)
assign(c.output.toOpenArray(12, 31), pubkey.toCanonicalAddress())
ok()
func sha256(c: Computation): EvmResultVoid =
let
wordCount = wordCount(c.msg.data.len)
gasFee = GasSHA256 + wordCount.GasInt * GasSHA256Word
? c.gasMeter.consumeGas(gasFee, reason="SHA256 Precompile")
assign(c.output, sha2.sha256.digest(c.msg.data).data)
ok()
func ripemd160(c: Computation): EvmResultVoid =
let
wordCount = wordCount(c.msg.data.len)
gasFee = GasRIPEMD160 + wordCount.GasInt * GasRIPEMD160Word
? c.gasMeter.consumeGas(gasFee, reason="RIPEMD160 Precompile")
c.output.setLen(32)
assign(c.output.toOpenArray(12, 31), ripemd.ripemd160.digest(c.msg.data).data)
ok()
func identity(c: Computation): EvmResultVoid =
let
wordCount = wordCount(c.msg.data.len)
gasFee = GasIdentity + wordCount.GasInt * GasIdentityWord
? c.gasMeter.consumeGas(gasFee, reason="Identity Precompile")
assign(c.output, c.msg.data)
ok()
func modExpFee(c: Computation,
baseLen, expLen, modLen: UInt256,
fork: EVMFork): EvmResult[GasInt] =
template data: untyped {.dirty.} =
c.msg.data
func mulComplexity(x: UInt256): UInt256 =
## Estimates the difficulty of Karatsuba multiplication
if x <= 64.u256: x * x
elif x <= 1024.u256: x * x div 4.u256 + 96.u256 * x - 3072.u256
else: x * x div 16.u256 + 480.u256 * x - 199680.u256
func mulComplexityEIP2565(x: UInt256): UInt256 =
# gas = ceil(x div 8) ^ 2
result = x + 7
result = result div 8
result = result * result
let adjExpLen = block:
let
baseL = baseLen.safeInt
expL = expLen.safeInt
first32 = if baseL.uint64 + expL.uint64 < high(int32).uint64 and baseL < data.len:
data.rangeToPadded[:UInt256](96 + baseL, 95 + baseL + expL, min(expL, 32))
else:
0.u256
if expLen <= 32:
if first32.isZero(): 0.u256
else: first32.log2.u256 # highest-bit in exponent
else:
if not first32.isZero:
8.u256 * (expLen - 32.u256) + first32.log2.u256
else:
8.u256 * (expLen - 32.u256)
template gasCalc(comp, divisor: untyped): untyped =
(
max(modLen, baseLen).comp *
max(adjExpLen, 1.u256)
) div divisor
# EIP2565: modExp gas cost
let gasFee = if fork >= FkBerlin: gasCalc(mulComplexityEIP2565, GasQuadDivisorEIP2565)
else: gasCalc(mulComplexity, GasQuadDivisor)
if gasFee > high(GasInt).u256:
return err(gasErr(OutOfGas))
var res = gasFee.truncate(GasInt)
# EIP2565: modExp gas cost
if fork >= FkBerlin and res < 200.GasInt:
res = 200.GasInt
ok(res)
func modExp(c: Computation, fork: EVMFork = FkByzantium): EvmResultVoid =
## Modular exponentiation precompiled contract
## Yellow Paper Appendix E
## EIP-198 - https://github.com/ethereum/EIPs/blob/master/EIPS/eip-198.md
# Parsing the data
template data: untyped {.dirty.} =
c.msg.data
let # lengths Base, Exponent, Modulus
baseL = data.rangeToPadded[:UInt256](0, 31, 32)
expL = data.rangeToPadded[:UInt256](32, 63, 32)
modL = data.rangeToPadded[:UInt256](64, 95, 32)
baseLen = baseL.safeInt
expLen = expL.safeInt
modLen = modL.safeInt
let gasFee = ? modExpFee(c, baseL, expL, modL, fork)
? c.gasMeter.consumeGas(gasFee, reason="ModExp Precompile")
if baseLen == 0 and modLen == 0:
# This is a special case where expLength can be very big.
c.output = @[]
return ok()
const maxSize = int32.high.u256
if baseL > maxSize or expL > maxSize or modL > maxSize:
return err(prcErr(PrcInvalidParam))
# TODO:
# add EVM special case:
# - modulo <= 1: return zero
# - exp == zero: return one
let output = modExp(
data.rangeToPadded(96, baseLen),
data.rangeToPadded(96 + baseLen, expLen),
data.rangeToPadded(96 + baseLen + expLen, modLen)
)
# maximum output len is the same as modLen
# if it less than modLen, it will be zero padded at left
if output.len >= modLen:
assign(c.output, output.toOpenArray(output.len-modLen, output.len-1))
else:
c.output = newSeq[byte](modLen)
assign(c.output.toOpenArray(c.output.len-output.len, c.output.len-1), output)
ok()
func bn256ecAdd(c: Computation, fork: EVMFork = FkByzantium): EvmResultVoid =
let gasFee = if fork < FkIstanbul: GasECAdd else: GasECAddIstanbul
? c.gasMeter.consumeGas(gasFee, reason = "ecAdd Precompile")
var
input: array[128, byte]
output: array[64, byte]
# Padding data
let len = min(c.msg.data.len, 128) - 1
input[0..len] = c.msg.data[0..len]
var p1 = ? G1.getPoint(input.toOpenArray(0, 63))
var p2 = ? G1.getPoint(input.toOpenArray(64, 127))
var apo = (p1 + p2).toAffine()
if isSome(apo):
# we can discard here because we supply proper buffer
discard apo.get().toBytes(output)
assign(c.output, output)
ok()
func bn256ecMul(c: Computation, fork: EVMFork = FkByzantium): EvmResultVoid =
let gasFee = if fork < FkIstanbul: GasECMul else: GasECMulIstanbul
? c.gasMeter.consumeGas(gasFee, reason="ecMul Precompile")
var
input: array[96, byte]
output: array[64, byte]
# Padding data
let len = min(c.msg.data.len, 96) - 1
input[0..len] = c.msg.data[0..len]
var p1 = ? G1.getPoint(input.toOpenArray(0, 63))
var fr = ? getFR(input.toOpenArray(64, 95))
var apo = (p1 * fr).toAffine()
if isSome(apo):
# we can discard here because we supply buffer of proper size
discard apo.get().toBytes(output)
assign(c.output, output)
ok()
func bn256ecPairing(c: Computation, fork: EVMFork = FkByzantium): EvmResultVoid =
let msglen = c.msg.data.len
if msglen mod 192 != 0:
return err(prcErr(PrcInvalidParam))
let numPoints = GasInt msglen div 192
let gasFee = if fork < FkIstanbul:
GasECPairingBase + numPoints * GasECPairingPerPoint
else:
GasECPairingBaseIstanbul + numPoints * GasECPairingPerPointIstanbul
? c.gasMeter.consumeGas(gasFee, reason="ecPairing Precompile")
var output: array[32, byte]
if msglen == 0:
# we can discard here because we supply buffer of proper size
discard BNU256.one().toBytes(output)
else:
# Calculate number of pairing pairs
let count = msglen div 192
# Pairing accumulator
var acc = FQ12.one()
for i in 0..<count:
let s = i * 192
# Loading AffinePoint[G1], bytes from [0..63]
var p1 = ? G1.getPoint(c.msg.data.toOpenArray(s, s + 63))
# Loading AffinePoint[G2], bytes from [64..191]
var p2 = ? G2.getPoint(c.msg.data.toOpenArray(s + 64, s + 191))
# Accumulate pairing result
acc = acc * pairing(p1, p2)
if acc == FQ12.one():
# we can discard here because we supply buffer of proper size
discard BNU256.one().toBytes(output)
assign(c.output, output)
ok()
func blake2bf(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if len(input) == blake2FInputLength:
let gasFee = GasInt(beLoad32(input, 0))
? c.gasMeter.consumeGas(gasFee, reason="blake2bf Precompile")
var output: array[64, byte]
if not blake2b_F(input, output):
return err(prcErr(PrcInvalidParam))
else:
assign(c.output, output)
ok()
func blsG1Add(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if input.len != 256:
return err(prcErr(PrcInvalidParam))
? c.gasMeter.consumeGas(Bls12381G1AddGas, reason="blsG1Add Precompile")
var a, b: BLS_G1
if not a.decodePoint(input.toOpenArray(0, 127)):
return err(prcErr(PrcInvalidPoint))
if not b.decodePoint(input.toOpenArray(128, 255)):
return err(prcErr(PrcInvalidPoint))
a.add b
c.output = newSeq[byte](128)
if not encodePoint(a, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
func blsG1Mul(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if input.len != 160:
return err(prcErr(PrcInvalidParam))
? c.gasMeter.consumeGas(Bls12381G1MulGas, reason="blsG1Mul Precompile")
var a: BLS_G1
if not a.decodePoint(input.toOpenArray(0, 127)):
return err(prcErr(PrcInvalidPoint))
var scalar: BLS_SCALAR
if not scalar.fromBytes(input.toOpenArray(128, 159)):
return err(prcErr(PrcInvalidParam))
a.mul(scalar)
c.output = newSeq[byte](128)
if not encodePoint(a, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
const
Bls12381MultiExpDiscountTable = [
1200, 888, 764, 641, 594, 547, 500, 453, 438, 423,
408, 394, 379, 364, 349, 334, 330, 326, 322, 318,
314, 310, 306, 302, 298, 294, 289, 285, 281, 277,
273, 269, 268, 266, 265, 263, 262, 260, 259, 257,
256, 254, 253, 251, 250, 248, 247, 245, 244, 242,
241, 239, 238, 236, 235, 233, 232, 231, 229, 228,
226, 225, 223, 222, 221, 220, 219, 219, 218, 217,
216, 216, 215, 214, 213, 213, 212, 211, 211, 210,
209, 208, 208, 207, 206, 205, 205, 204, 203, 202,
202, 201, 200, 199, 199, 198, 197, 196, 196, 195,
194, 193, 193, 192, 191, 191, 190, 189, 188, 188,
187, 186, 185, 185, 184, 183, 182, 182, 181, 180,
179, 179, 178, 177, 176, 176, 175, 174
]
func calcBlsMultiExpGas(K: GasInt, gasCost: GasInt): GasInt =
# Calculate G1 point, scalar value pair length
if K == 0:
# Return 0 gas for small input length
return 0.GasInt
const dLen = Bls12381MultiExpDiscountTable.len
# Lookup discount value for G1 point, scalar value pair length
let discount = if K < dLen: GasInt Bls12381MultiExpDiscountTable[K-1]
else: GasInt Bls12381MultiExpDiscountTable[dLen-1]
# Calculate gas and return the result
result = (K * gasCost * discount) div 1000
func blsG1MultiExp(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
const L = 160
if (input.len == 0) or ((input.len mod L) != 0):
return err(prcErr(PrcInvalidParam))
let
K = input.len div L
gas = calcBlsMultiExpGas(GasInt K, Bls12381G1MulGas)
? c.gasMeter.consumeGas(gas, reason="blsG1MultiExp Precompile")
var
p: BLS_G1
s: BLS_SCALAR
acc: BLS_G1
# Decode point scalar pairs
for i in 0..<K:
let off = L * i
# Decode G1 point
if not p.decodePoint(input.toOpenArray(off, off+127)):
return err(prcErr(PrcInvalidPoint))
# Decode scalar value
if not s.fromBytes(input.toOpenArray(off+128, off+159)):
return err(prcErr(PrcInvalidParam))
p.mul(s)
if i == 0:
acc = p
else:
acc.add(p)
c.output = newSeq[byte](128)
if not encodePoint(acc, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
func blsG2Add(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if input.len != 512:
return err(prcErr(PrcInvalidParam))
? c.gasMeter.consumeGas(Bls12381G2AddGas, reason="blsG2Add Precompile")
var a, b: BLS_G2
if not a.decodePoint(input.toOpenArray(0, 255)):
return err(prcErr(PrcInvalidPoint))
if not b.decodePoint(input.toOpenArray(256, 511)):
return err(prcErr(PrcInvalidPoint))
a.add b
c.output = newSeq[byte](256)
if not encodePoint(a, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
func blsG2Mul(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if input.len != 288:
return err(prcErr(PrcInvalidParam))
? c.gasMeter.consumeGas(Bls12381G2MulGas, reason="blsG2Mul Precompile")
var a: BLS_G2
if not a.decodePoint(input.toOpenArray(0, 255)):
return err(prcErr(PrcInvalidPoint))
var scalar: BLS_SCALAR
if not scalar.fromBytes(input.toOpenArray(256, 287)):
return err(prcErr(PrcInvalidParam))
a.mul(scalar)
c.output = newSeq[byte](256)
if not encodePoint(a, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
func blsG2MultiExp(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
const L = 288
if (input.len == 0) or ((input.len mod L) != 0):
return err(prcErr(PrcInvalidParam))
let
K = input.len div L
gas = calcBlsMultiExpGas(GasInt K, Bls12381G2MulGas)
? c.gasMeter.consumeGas(gas, reason="blsG2MultiExp Precompile")
var
p: BLS_G2
s: BLS_SCALAR
acc: BLS_G2
# Decode point scalar pairs
for i in 0..<K:
let off = L * i
# Decode G1 point
if not p.decodePoint(input.toOpenArray(off, off+255)):
return err(prcErr(PrcInvalidPoint))
# Decode scalar value
if not s.fromBytes(input.toOpenArray(off+256, off+287)):
return err(prcErr(PrcInvalidParam))
p.mul(s)
if i == 0:
acc = p
else:
acc.add(p)
c.output = newSeq[byte](256)
if not encodePoint(acc, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
func blsPairing(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
const L = 384
if (input.len == 0) or ((input.len mod L) != 0):
return err(prcErr(PrcInvalidParam))
let
K = input.len div L
gas = Bls12381PairingBaseGas + K.GasInt * Bls12381PairingPerPairGas
? c.gasMeter.consumeGas(gas, reason="blsG2Pairing Precompile")
var
g1: BLS_G1P
g2: BLS_G2P
acc: BLS_ACC
# Decode pairs
for i in 0..<K:
let off = L * i
# Decode G1 point
if not g1.decodePoint(input.toOpenArray(off, off+127)):
return err(prcErr(PrcInvalidPoint))
# Decode G2 point
if not g2.decodePoint(input.toOpenArray(off+128, off+383)):
return err(prcErr(PrcInvalidPoint))
# 'point is on curve' check already done,
# Here we need to apply subgroup checks.
if not g1.subgroupCheck:
return err(prcErr(PrcInvalidPoint))
if not g2.subgroupCheck:
return err(prcErr(PrcInvalidPoint))
# Update pairing engine with G1 and G2 points
if i == 0:
acc = millerLoop(g1, g2)
else:
acc.mul(millerLoop(g1, g2))
c.output = newSeq[byte](32)
if acc.check():
c.output[^1] = 1.byte
ok()
func blsMapG1(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if input.len != 64:
return err(prcErr(PrcInvalidParam))
? c.gasMeter.consumeGas(Bls12381MapG1Gas, reason="blsMapG1 Precompile")
var fe: BLS_FE
if not fe.decodeFE(input):
return err(prcErr(PrcInvalidPoint))
let p = fe.mapFPToG1()
c.output = newSeq[byte](128)
if not encodePoint(p, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
func blsMapG2(c: Computation): EvmResultVoid =
template input: untyped =
c.msg.data
if input.len != 128:
return err(prcErr(PrcInvalidParam))
? c.gasMeter.consumeGas(Bls12381MapG2Gas, reason="blsMapG2 Precompile")
var fe: BLS_FE2
if not fe.decodeFE(input):
return err(prcErr(PrcInvalidPoint))
let p = fe.mapFPToG2()
c.output = newSeq[byte](256)
if not encodePoint(p, c.output):
return err(prcErr(PrcInvalidPoint))
ok()
proc pointEvaluation(c: Computation): EvmResultVoid =
# Verify p(z) = y given commitment that corresponds to the polynomial p(x) and a KZG proof.
# Also verify that the provided commitment matches the provided versioned_hash.
# The data is encoded as follows: versioned_hash | z | y | commitment | proof |
template input: untyped =
c.msg.data
? c.gasMeter.consumeGas(POINT_EVALUATION_PRECOMPILE_GAS,
reason = "EIP-4844 Point Evaluation Precompile")
pointEvaluation(input).isOkOr:
return err(prcErr(PrcValidationError))
# return a constant
c.output = @PointEvaluationResult
ok()
# ------------------------------------------------------------------------------
# Public functions
# ------------------------------------------------------------------------------
iterator activePrecompiles*(fork: EVMFork): EthAddress =
var res: EthAddress
let maxPrecompileAddr = getMaxPrecompileAddr(fork)
for c in PrecompileAddresses.low..maxPrecompileAddr:
if validPrecompileAddr(c.byte, maxPrecompileAddr.byte):
res[^1] = c.byte
yield res
func activePrecompilesList*(fork: EVMFork): seq[EthAddress] =
for address in activePrecompiles(fork):
result.add address
proc execPrecompiles*(c: Computation, fork: EVMFork): bool =
for i in 0..18:
if c.msg.codeAddress[i] != 0:
return false
let lb = c.msg.codeAddress[19]
if not validPrecompileAddr(lb, fork):
return false
let precompile = PrecompileAddresses(lb)
let res = case precompile
of paEcRecover: ecRecover(c)
of paSha256: sha256(c)
of paRipeMd160: ripemd160(c)
of paIdentity: identity(c)
of paModExp: modExp(c, fork)
of paEcAdd: bn256ecAdd(c, fork)
of paEcMul: bn256ecMul(c, fork)
of paPairing: bn256ecPairing(c, fork)
of paBlake2bf: blake2bf(c)
of paPointEvaluation: pointEvaluation(c)
of paBlsG1Add: blsG1Add(c)
of paBlsG1Mul: blsG1Mul(c)
of paBlsG1MultiExp: blsG1MultiExp(c)
of paBlsG2Add: blsG2Add(c)
of paBlsG2Mul: blsG2Mul(c)
of paBlsG2MultiExp: blsG2MultiExp(c)
of paBlsPairing: blsPairing(c)
of paBlsMapG1: blsMapG1(c)
of paBlsMapG2: blsMapG2(c)
if res.isErr:
if res.error.code == EvmErrorCode.OutOfGas:
c.setError(EVMC_OUT_OF_GAS, $res.error.code, true)
else:
if fork >= FkByzantium and precompile > paIdentity:
c.setError(EVMC_PRECOMPILE_FAILURE, $res.error.code, true)
else:
# swallow any other precompiles errors
debug "execPrecompiles validation error", errCode = $res.error.code
true