op-program: define as go module, de-duplicate preimage ABI bindings

op-preimage/hints.go

@@ -43,7 +43,9 @@ func NewHintReader(rw io.ReadWriter) *HintReader {
 	return &HintReader{rw: rw}
 }
 
-func (hr *HintReader) NextHint(router func(hint string) error) error {
+type HintHandler func(hint string) error
+
+func (hr *HintReader) NextHint(router HintHandler) error {
 	var length uint32
 	if err := binary.Read(hr.rw, binary.BigEndian, &length); err != nil {
 		if err == io.EOF {

op-preimage/oracle.go

@@ -44,8 +44,9 @@ type OracleServer struct {
 func NewOracleServer(rw io.ReadWriter) *OracleServer {
 	return &OracleServer{rw: rw}
 }
+type PreimageGetter func(key [32]byte) ([]byte, error)
 
-func (o *OracleServer) NextPreimageRequest(getPreimage func(key [32]byte) ([]byte, error)) error {
+func (o *OracleServer) NextPreimageRequest(getPreimage PreimageGetter) error {
 	var key [32]byte
 	if _, err := io.ReadFull(o.rw, key[:]); err != nil {
 		if err == io.EOF {

op-program/client/boot.go

@@ -5,7 +5,7 @@ import (
 	"encoding/json"
 
 	"github.com/ethereum-optimism/optimism/op-node/rollup"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/params"
 )

op-program/client/boot_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 
 	"github.com/ethereum-optimism/optimism/op-node/chaincfg"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/stretchr/testify/require"

op-program/client/l1/hints.go

@@ -3,7 +3,7 @@ package l1
 import (
 	"github.com/ethereum/go-ethereum/common"
 
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 const (

op-program/client/l1/oracle.go

@@ -9,7 +9,7 @@ import (
 
 	"github.com/ethereum-optimism/optimism/op-node/eth"
 	"github.com/ethereum-optimism/optimism/op-program/client/mpt"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 type Oracle interface {

op-program/client/l1/oracle_test.go

@@ -16,7 +16,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-node/eth"
 	"github.com/ethereum-optimism/optimism/op-node/testutils"
 	"github.com/ethereum-optimism/optimism/op-program/client/mpt"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 // testBlock tests that the given block with receipts can be passed through the preimage oracle.

op-program/client/l2/hints.go

@@ -3,7 +3,7 @@ package l2
 import (
 	"github.com/ethereum/go-ethereum/common"
 
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 const (

op-program/client/l2/oracle.go

@@ -9,7 +9,7 @@ import (
 
 	"github.com/ethereum-optimism/optimism/op-node/eth"
 	"github.com/ethereum-optimism/optimism/op-program/client/mpt"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 // StateOracle defines the high-level API used to retrieve L2 state data pre-images

op-program/client/l2/oracle_test.go

@@ -16,7 +16,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-node/eth"
 	"github.com/ethereum-optimism/optimism/op-node/testutils"
 	"github.com/ethereum-optimism/optimism/op-program/client/mpt"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 func mockPreimageOracle(t *testing.T) (po *PreimageOracle, hintsMock *mock.Mock, preimages map[common.Hash][]byte) {

op-program/client/program.go

@@ -17,7 +17,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-program/client/l1"
 	"github.com/ethereum-optimism/optimism/op-program/client/l2"
 	oppio "github.com/ethereum-optimism/optimism/op-program/io"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 // Main executes the client program in a detached context and exits the current process.

op-program/go.mod

+module github.com/ethereum-optimism/optimism/op-program
+
+go 1.20
+
+// Note: optimism, op-preimage, are replaced with local monorepo dependencies.
+// go-ethereum is replaced with the remote op-geth dependency.
+require (
+	github.com/ethereum-optimism/optimism v0.0.0
+	github.com/ethereum-optimism/optimism/op-preimage v0.0.0
+	github.com/ethereum/go-ethereum v1.11.6
+	github.com/hashicorp/golang-lru/v2 v2.0.1
+	github.com/stretchr/testify v1.8.2
+	github.com/urfave/cli v1.22.9
+)
+
+require (
+	github.com/DataDog/zstd v1.5.2 // indirect
+	github.com/VictoriaMetrics/fastcache v1.10.0 // indirect
+	github.com/benbjohnson/clock v1.3.0 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/btcsuite/btcd v0.23.3 // indirect
+	github.com/btcsuite/btcd/btcec/v2 v2.2.0 // indirect
+	github.com/btcsuite/btcd/btcutil v1.1.0 // indirect
+	github.com/btcsuite/btcd/chaincfg/chainhash v1.0.1 // indirect
+	github.com/btcsuite/btclog v0.0.0-20170628155309-84c8d2346e9f // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/cockroachdb/errors v1.9.1 // indirect
+	github.com/cockroachdb/logtags v0.0.0-20230118201751-21c54148d20b // indirect
+	github.com/cockroachdb/pebble v0.0.0-20230209160836-829675f94811 // indirect
+	github.com/cockroachdb/redact v1.1.3 // indirect
+	github.com/containerd/cgroups v1.1.0 // indirect
+	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
+	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/davidlazar/go-crypto v0.0.0-20200604182044-b73af7476f6c // indirect
+	github.com/deckarep/golang-set/v2 v2.1.0 // indirect
+	github.com/decred/dcrd/crypto/blake256 v1.0.0 // indirect
+	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.1.0 // indirect
+	github.com/docker/go-units v0.5.0 // indirect
+	github.com/edsrzf/mmap-go v1.1.0 // indirect
+	github.com/elastic/gosigar v0.14.2 // indirect
+	github.com/fjl/memsize v0.0.1 // indirect
+	github.com/flynn/noise v1.0.0 // indirect
+	github.com/francoispqt/gojay v1.2.13 // indirect
+	github.com/fsnotify/fsnotify v1.6.0 // indirect
+	github.com/gballet/go-libpcsclite v0.0.0-20191108122812-4678299bea08 // indirect
+	github.com/getsentry/sentry-go v0.18.0 // indirect
+	github.com/go-ole/go-ole v1.2.6 // indirect
+	github.com/go-stack/stack v1.8.1 // indirect
+	github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 // indirect
+	github.com/godbus/dbus/v5 v5.1.0 // indirect
+	github.com/gofrs/flock v0.8.1 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang-jwt/jwt/v4 v4.4.2 // indirect
+	github.com/golang/mock v1.6.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/golang/snappy v0.0.5-0.20220116011046-fa5810519dcb // indirect
+	github.com/google/gopacket v1.1.19 // indirect
+	github.com/google/pprof v0.0.0-20230207041349-798e818bf904 // indirect
+	github.com/google/uuid v1.3.0 // indirect
+	github.com/gorilla/websocket v1.5.0 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/hashicorp/go-bexpr v0.1.11 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/hashicorp/golang-lru v0.5.5-0.20210104140557-80c98217689d // indirect
+	github.com/holiman/bloomfilter/v2 v2.0.3 // indirect
+	github.com/holiman/uint256 v1.2.2-0.20230321075855-87b91420868c // indirect
+	github.com/huin/goupnp v1.1.0 // indirect
+	github.com/ipfs/go-cid v0.3.2 // indirect
+	github.com/ipfs/go-datastore v0.6.0 // indirect
+	github.com/ipfs/go-ds-leveldb v0.5.0 // indirect
+	github.com/ipfs/go-log/v2 v2.5.1 // indirect
+	github.com/jackpal/go-nat-pmp v1.0.2 // indirect
+	github.com/jbenet/go-temp-err-catcher v0.1.0 // indirect
+	github.com/jbenet/goprocess v0.1.4 // indirect
+	github.com/klauspost/compress v1.15.15 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.3 // indirect
+	github.com/koron/go-ssdp v0.0.3 // indirect
+	github.com/kr/pretty v0.3.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/libp2p/go-buffer-pool v0.1.0 // indirect
+	github.com/libp2p/go-cidranger v1.1.0 // indirect
+	github.com/libp2p/go-flow-metrics v0.1.0 // indirect
+	github.com/libp2p/go-libp2p v0.25.1 // indirect
+	github.com/libp2p/go-libp2p-asn-util v0.2.0 // indirect
+	github.com/libp2p/go-libp2p-pubsub v0.9.3 // indirect
+	github.com/libp2p/go-libp2p-testing v0.12.0 // indirect
+	github.com/libp2p/go-mplex v0.7.0 // indirect
+	github.com/libp2p/go-msgio v0.3.0 // indirect
+	github.com/libp2p/go-nat v0.1.0 // indirect
+	github.com/libp2p/go-netroute v0.2.1 // indirect
+	github.com/libp2p/go-reuseport v0.2.0 // indirect
+	github.com/libp2p/go-yamux/v4 v4.0.0 // indirect
+	github.com/marten-seemann/tcp v0.0.0-20210406111302-dfbc87cc63fd // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.17 // indirect
+	github.com/mattn/go-runewidth v0.0.14 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/miekg/dns v1.1.50 // indirect
+	github.com/mikioh/tcpinfo v0.0.0-20190314235526-30a79bb1804b // indirect
+	github.com/mikioh/tcpopt v0.0.0-20190314235656-172688c1accc // indirect
+	github.com/minio/sha256-simd v1.0.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/mitchellh/pointerstructure v1.2.1 // indirect
+	github.com/mr-tron/base58 v1.2.0 // indirect
+	github.com/multiformats/go-base32 v0.1.0 // indirect
+	github.com/multiformats/go-base36 v0.2.0 // indirect
+	github.com/multiformats/go-multiaddr v0.8.0 // indirect
+	github.com/multiformats/go-multiaddr-dns v0.3.1 // indirect
+	github.com/multiformats/go-multiaddr-fmt v0.1.0 // indirect
+	github.com/multiformats/go-multibase v0.1.1 // indirect
+	github.com/multiformats/go-multicodec v0.8.1 // indirect
+	github.com/multiformats/go-multihash v0.2.1 // indirect
+	github.com/multiformats/go-multistream v0.4.1 // indirect
+	github.com/multiformats/go-varint v0.0.7 // indirect
+	github.com/olekukonko/tablewriter v0.0.5 // indirect
+	github.com/onsi/ginkgo/v2 v2.8.1 // indirect
+	github.com/opencontainers/runtime-spec v1.0.2 // indirect
+	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/prometheus/client_golang v1.14.0 // indirect
+	github.com/prometheus/client_model v0.3.0 // indirect
+	github.com/prometheus/common v0.39.0 // indirect
+	github.com/prometheus/procfs v0.9.0 // indirect
+	github.com/quic-go/qpack v0.4.0 // indirect
+	github.com/quic-go/qtls-go1-18 v0.2.0 // indirect
+	github.com/quic-go/qtls-go1-19 v0.2.0 // indirect
+	github.com/quic-go/qtls-go1-20 v0.1.0 // indirect
+	github.com/quic-go/quic-go v0.32.0 // indirect
+	github.com/quic-go/webtransport-go v0.5.1 // indirect
+	github.com/raulk/go-watchdog v1.3.0 // indirect
+	github.com/rivo/uniseg v0.4.3 // indirect
+	github.com/rogpeppe/go-internal v1.9.0 // indirect
+	github.com/rs/cors v1.8.2 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/shirou/gopsutil v3.21.11+incompatible // indirect
+	github.com/spaolacci/murmur3 v1.1.0 // indirect
+	github.com/status-im/keycard-go v0.2.0 // indirect
+	github.com/stretchr/objx v0.5.0 // indirect
+	github.com/syndtr/goleveldb v1.0.1-0.20220614013038-64ee5596c38a // indirect
+	github.com/tklauser/go-sysconf v0.3.10 // indirect
+	github.com/tklauser/numcpus v0.5.0 // indirect
+	github.com/tyler-smith/go-bip39 v1.1.0 // indirect
+	github.com/urfave/cli/v2 v2.17.2-0.20221006022127-8f469abc00aa // indirect
+	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
+	github.com/yusufpapurcu/wmi v1.2.2 // indirect
+	go.uber.org/atomic v1.10.0 // indirect
+	go.uber.org/dig v1.16.1 // indirect
+	go.uber.org/fx v1.19.1 // indirect
+	go.uber.org/multierr v1.9.0 // indirect
+	go.uber.org/zap v1.24.0 // indirect
+	golang.org/x/crypto v0.8.0 // indirect
+	golang.org/x/exp v0.0.0-20230213192124-5e25df0256eb // indirect
+	golang.org/x/mod v0.9.0 // indirect
+	golang.org/x/net v0.9.0 // indirect
+	golang.org/x/sync v0.1.0 // indirect
+	golang.org/x/sys v0.7.0 // indirect
+	golang.org/x/term v0.7.0 // indirect
+	golang.org/x/text v0.9.0 // indirect
+	golang.org/x/time v0.0.0-20220922220347-f3bd1da661af // indirect
+	golang.org/x/tools v0.7.0 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+	gopkg.in/natefinch/lumberjack.v2 v2.0.0 // indirect
+	gopkg.in/natefinch/npipe.v2 v2.0.0-20160621034901-c1b8fa8bdcce // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+	lukechampine.com/blake3 v1.1.7 // indirect
+	nhooyr.io/websocket v1.8.7 // indirect
+)
+
+replace (
+	github.com/ethereum-optimism/optimism v0.0.0 => ../
+	github.com/ethereum-optimism/optimism/op-preimage v0.0.0 => ../op-preimage
+	github.com/ethereum/go-ethereum v1.11.6 => github.com/ethereum-optimism/op-geth v1.101106.0-rc.2
+)

op-program/host/host.go

@@ -20,7 +20,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-program/host/kvstore"
 	"github.com/ethereum-optimism/optimism/op-program/host/prefetcher"
 	oppio "github.com/ethereum-optimism/optimism/op-program/io"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	opservice "github.com/ethereum-optimism/optimism/op-service"
 	opclient "github.com/ethereum-optimism/optimism/op-service/client"
 	"github.com/ethereum/go-ethereum/common"

op-program/host/host_test.go

@@ -13,7 +13,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-program/host/config"
 	"github.com/ethereum-optimism/optimism/op-program/host/kvstore"
 	"github.com/ethereum-optimism/optimism/op-program/io"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/log"
 	"github.com/stretchr/testify/require"

op-program/host/kvstore/local.go

@@ -27,7 +27,7 @@ var (
 )
 
 func (s *LocalPreimageSource) Get(key common.Hash) ([]byte, error) {
-	switch key {
+	switch [32]byte(key) {
 	case l1HeadKey:
 		return s.config.L1Head.Bytes(), nil
 	case l2HeadKey:

op-program/host/kvstore/local_test.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/ethereum-optimism/optimism/op-node/chaincfg"
 	"github.com/ethereum-optimism/optimism/op-program/host/config"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/stretchr/testify/require"

op-program/host/kvstore/splitter.go

 package kvstore
 
 import (
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 )
 
@@ -19,7 +19,7 @@ func NewPreimageSourceSplitter(local PreimageSource, global PreimageSource) *Pre
 	}
 }
 
-func (s *PreimageSourceSplitter) Get(key common.Hash) ([]byte, error) {
+func (s *PreimageSourceSplitter) Get(key [32]byte) ([]byte, error) {
 	if key[0] == byte(preimage.LocalKeyType) {
 		return s.local(key)
 	}

op-program/host/kvstore/splitter_test.go

@@ -3,7 +3,7 @@ package kvstore
 import (
 	"testing"
 
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/stretchr/testify/require"
 )

op-program/host/prefetcher/prefetcher.go

@@ -11,7 +11,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-program/client/l2"
 	"github.com/ethereum-optimism/optimism/op-program/client/mpt"
 	"github.com/ethereum-optimism/optimism/op-program/host/kvstore"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/types"

op-program/host/prefetcher/prefetcher_test.go

@@ -19,7 +19,7 @@ import (
 	"github.com/ethereum-optimism/optimism/op-program/client/l2"
 	"github.com/ethereum-optimism/optimism/op-program/client/mpt"
 	"github.com/ethereum-optimism/optimism/op-program/host/kvstore"
-	"github.com/ethereum-optimism/optimism/op-program/preimage"
+	"github.com/ethereum-optimism/optimism/op-preimage"
 )
 
 func TestNoHint(t *testing.T) {

op-program/preimage/hints.go

-package preimage
-
-import (
-	"encoding/binary"
-	"fmt"
-	"io"
-)
-
-// HintWriter writes hints to an io.Writer (e.g. a special file descriptor, or a debug log),
-// for a pre-image oracle service to prepare specific pre-images.
-type HintWriter struct {
-	rw io.ReadWriter
-}
-
-var _ Hinter = (*HintWriter)(nil)
-
-func NewHintWriter(rw io.ReadWriter) *HintWriter {
-	return &HintWriter{rw: rw}
-}
-
-func (hw *HintWriter) Hint(v Hint) {
-	hint := v.Hint()
-	var hintBytes []byte
-	hintBytes = binary.BigEndian.AppendUint32(hintBytes, uint32(len(hint)))
-	hintBytes = append(hintBytes, []byte(hint)...)
-	_, err := hw.rw.Write(hintBytes)
-	if err != nil {
-		panic(fmt.Errorf("failed to write pre-image hint: %w", err))
-	}
-	_, err = hw.rw.Read([]byte{0})
-	if err != nil {
-		panic(fmt.Errorf("failed to read pre-image hint ack: %w", err))
-	}
-}
-
-// HintReader reads the hints of HintWriter and passes them to a router for preparation of the requested pre-images.
-// Onchain the written hints are no-op.
-type HintReader struct {
-	rw io.ReadWriter
-}
-
-func NewHintReader(rw io.ReadWriter) *HintReader {
-	return &HintReader{rw: rw}
-}
-
-type HintHandler func(hint string) error
-
-func (hr *HintReader) NextHint(router HintHandler) error {
-	var length uint32
-	if err := binary.Read(hr.rw, binary.BigEndian, &length); err != nil {
-		if err == io.EOF {
-			return io.EOF
-		}
-		return fmt.Errorf("failed to read hint length prefix: %w", err)
-	}
-	payload := make([]byte, length)
-	if length > 0 {
-		if _, err := io.ReadFull(hr.rw, payload); err != nil {
-			return fmt.Errorf("failed to read hint payload (length %d): %w", length, err)
-		}
-	}
-	if err := router(string(payload)); err != nil {
-		// write back on error to unblock the HintWriter
-		_, _ = hr.rw.Write([]byte{0})
-		return fmt.Errorf("failed to handle hint: %w", err)
-	}
-	if _, err := hr.rw.Write([]byte{0}); err != nil {
-		return fmt.Errorf("failed to write trailing no-op byte to unblock hint writer: %w", err)
-	}
-	return nil
-}

op-program/preimage/hints_test.go

-package preimage
-
-import (
-	"bytes"
-	"crypto/rand"
-	"errors"
-	"io"
-	"sync"
-	"testing"
-	"time"
-
-	"github.com/stretchr/testify/require"
-)
-
-type rawHint string
-
-func (rh rawHint) Hint() string {
-	return string(rh)
-}
-
-func TestHints(t *testing.T) {
-	// Note: pretty much every string is valid communication:
-	// length, payload, 0. Worst case you run out of data, or allocate too much.
-	testHint := func(hints ...string) {
-		a, b := bidirectionalPipe()
-		var wg sync.WaitGroup
-		wg.Add(2)
-
-		go func() {
-			hw := NewHintWriter(a)
-			for _, h := range hints {
-				hw.Hint(rawHint(h))
-			}
-			wg.Done()
-		}()
-
-		got := make(chan string, len(hints))
-		go func() {
-			defer wg.Done()
-			hr := NewHintReader(b)
-			for i := 0; i < len(hints); i++ {
-				err := hr.NextHint(func(hint string) error {
-					got <- hint
-					return nil
-				})
-				if err == io.EOF {
-					break
-				}
-				require.NoError(t, err)
-			}
-		}()
-		if waitTimeout(&wg) {
-			t.Error("hint read/write stuck")
-		}
-
-		require.Equal(t, len(hints), len(got), "got all hints")
-		for _, h := range hints {
-			require.Equal(t, h, <-got, "hints match")
-		}
-	}
-
-	t.Run("empty hint", func(t *testing.T) {
-		testHint("")
-	})
-	t.Run("hello world", func(t *testing.T) {
-		testHint("hello world")
-	})
-	t.Run("zero byte", func(t *testing.T) {
-		testHint(string([]byte{0}))
-	})
-	t.Run("many zeroes", func(t *testing.T) {
-		testHint(string(make([]byte, 1000)))
-	})
-	t.Run("random data", func(t *testing.T) {
-		dat := make([]byte, 1000)
-		_, _ = rand.Read(dat[:])
-		testHint(string(dat))
-	})
-	t.Run("multiple hints", func(t *testing.T) {
-		testHint("give me header a", "also header b", "foo bar")
-	})
-	t.Run("unexpected EOF", func(t *testing.T) {
-		var buf bytes.Buffer
-		hw := NewHintWriter(&buf)
-		hw.Hint(rawHint("hello"))
-		_, _ = buf.Read(make([]byte, 1)) // read one byte so it falls short, see if it's detected
-		hr := NewHintReader(&buf)
-		err := hr.NextHint(func(hint string) error { return nil })
-		require.ErrorIs(t, err, io.ErrUnexpectedEOF)
-	})
-	t.Run("cb error", func(t *testing.T) {
-		a, b := bidirectionalPipe()
-		var wg sync.WaitGroup
-		wg.Add(2)
-
-		go func() {
-			hw := NewHintWriter(a)
-			hw.Hint(rawHint("one"))
-			hw.Hint(rawHint("two"))
-			wg.Done()
-		}()
-		go func() {
-			defer wg.Done()
-			hr := NewHintReader(b)
-			cbErr := errors.New("fail")
-			err := hr.NextHint(func(hint string) error { return cbErr })
-			require.ErrorIs(t, err, cbErr)
-			var readHint string
-			err = hr.NextHint(func(hint string) error {
-				readHint = hint
-				return nil
-			})
-			require.NoError(t, err)
-			require.Equal(t, readHint, "two")
-		}()
-		if waitTimeout(&wg) {
-			t.Error("read/write hint stuck")
-		}
-	})
-}
-
-// waitTimeout returns true iff wg.Wait timed out
-func waitTimeout(wg *sync.WaitGroup) bool {
-	done := make(chan struct{})
-	go func() {
-		wg.Wait()
-		close(done)
-	}()
-	select {
-	case <-time.After(time.Second * 30):
-		return true
-	case <-done:
-		return false
-	}
-}

op-program/preimage/iface.go

-package preimage
-
-import (
-	"encoding/binary"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-type Key interface {
-	// PreimageKey changes the Key commitment into a
-	// 32-byte type-prefixed preimage key.
-	PreimageKey() common.Hash
-}
-
-type Oracle interface {
-	// Get the full pre-image of a given pre-image key.
-	// This returns no error: the client state-transition
-	// is invalid if there is any missing pre-image data.
-	Get(key Key) []byte
-}
-
-type OracleFn func(key Key) []byte
-
-func (fn OracleFn) Get(key Key) []byte {
-	return fn(key)
-}
-
-// KeyType is the key-type of a pre-image, used to prefix the pre-image key with.
-type KeyType byte
-
-const (
-	// The zero key type is illegal to use, ensuring all keys are non-zero.
-	_ KeyType = 0
-	// LocalKeyType is for input-type pre-images, specific to the local program instance.
-	LocalKeyType KeyType = 1
-	// Keccak256KeyType is for keccak256 pre-images, for any global shared pre-images.
-	Keccak256KeyType KeyType = 2
-)
-
-// LocalIndexKey is a key local to the program, indexing a special program input.
-type LocalIndexKey uint64
-
-func (k LocalIndexKey) PreimageKey() (out common.Hash) {
-	out[0] = byte(LocalKeyType)
-	binary.BigEndian.PutUint64(out[24:], uint64(k))
-	return
-}
-
-// Keccak256Key wraps a keccak256 hash to use it as a typed pre-image key.
-type Keccak256Key common.Hash
-
-func (k Keccak256Key) PreimageKey() (out common.Hash) {
-	out = common.Hash(k)            // copy the keccak hash
-	out[0] = byte(Keccak256KeyType) // apply prefix
-	return
-}
-
-func (k Keccak256Key) String() string {
-	return common.Hash(k).String()
-}
-
-func (k Keccak256Key) TerminalString() string {
-	return common.Hash(k).String()
-}
-
-// Hint is an interface to enable any program type to function as a hint,
-// when passed to the Hinter interface, returning a string representation
-// of what data the host should prepare pre-images for.
-type Hint interface {
-	Hint() string
-}
-
-// Hinter is an interface to write hints to the host.
-// This may be implemented as a no-op or logging hinter
-// if the program is executing in a read-only environment
-// where the host is expected to have all pre-images ready.
-type Hinter interface {
-	Hint(v Hint)
-}
-
-type HinterFn func(v Hint)
-
-func (fn HinterFn) Hint(v Hint) {
-	fn(v)
-}

op-program/preimage/oracle.go

-package preimage
-
-import (
-	"encoding/binary"
-	"fmt"
-	"io"
-
-	"github.com/ethereum/go-ethereum/common"
-)
-
-// OracleClient implements the Oracle by writing the pre-image key to the given stream,
-// and reading back a length-prefixed value.
-type OracleClient struct {
-	rw io.ReadWriter
-}
-
-func NewOracleClient(rw io.ReadWriter) *OracleClient {
-	return &OracleClient{rw: rw}
-}
-
-var _ Oracle = (*OracleClient)(nil)
-
-func (o *OracleClient) Get(key Key) []byte {
-	h := key.PreimageKey()
-	if _, err := o.rw.Write(h[:]); err != nil {
-		panic(fmt.Errorf("failed to write key %s (%T) to pre-image oracle: %w", key, key, err))
-	}
-
-	var length uint64
-	if err := binary.Read(o.rw, binary.BigEndian, &length); err != nil {
-		panic(fmt.Errorf("failed to read pre-image length of key %s (%T) from pre-image oracle: %w", key, key, err))
-	}
-	payload := make([]byte, length)
-	if _, err := io.ReadFull(o.rw, payload); err != nil {
-		panic(fmt.Errorf("failed to read pre-image payload (length %d) of key %s (%T) from pre-image oracle: %w", length, key, key, err))
-	}
-
-	return payload
-}
-
-// OracleServer serves the pre-image requests of the OracleClient, implementing the same protocol as the onchain VM.
-type OracleServer struct {
-	rw io.ReadWriter
-}
-
-func NewOracleServer(rw io.ReadWriter) *OracleServer {
-	return &OracleServer{rw: rw}
-}
-
-type PreimageGetter func(key common.Hash) ([]byte, error)
-
-func (o *OracleServer) NextPreimageRequest(getPreimage PreimageGetter) error {
-	var key common.Hash
-	if _, err := io.ReadFull(o.rw, key[:]); err != nil {
-		if err == io.EOF {
-			return io.EOF
-		}
-		return fmt.Errorf("failed to read requested pre-image key: %w", err)
-	}
-	value, err := getPreimage(key)
-	if err != nil {
-		return fmt.Errorf("failed to serve pre-image %s request: %w", key, err)
-	}
-
-	if err := binary.Write(o.rw, binary.BigEndian, uint64(len(value))); err != nil {
-		return fmt.Errorf("failed to write length-prefix %d: %w", len(value), err)
-	}
-	if len(value) == 0 {
-		return nil
-	}
-	if _, err := o.rw.Write(value); err != nil {
-		return fmt.Errorf("failed to write pre-image value (%d long): %w", len(value), err)
-	}
-	return nil
-}

op-program/preimage/oracle_test.go

-package preimage
-
-import (
-	"bytes"
-	"crypto/rand"
-	"fmt"
-	"io"
-	"sync"
-	"testing"
-
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/crypto"
-	"github.com/stretchr/testify/require"
-)
-
-type readWritePair struct {
-	io.Reader
-	io.Writer
-}
-
-func bidirectionalPipe() (a, b io.ReadWriter) {
-	ar, bw := io.Pipe()
-	br, aw := io.Pipe()
-	return readWritePair{Reader: ar, Writer: aw}, readWritePair{Reader: br, Writer: bw}
-}
-
-func TestOracle(t *testing.T) {
-	testPreimage := func(preimages ...[]byte) {
-		a, b := bidirectionalPipe()
-		cl := NewOracleClient(a)
-		srv := NewOracleServer(b)
-
-		preimageByHash := make(map[common.Hash][]byte)
-		for _, p := range preimages {
-			k := Keccak256Key(crypto.Keccak256Hash(p))
-			preimageByHash[k.PreimageKey()] = p
-		}
-		for _, p := range preimages {
-			k := Keccak256Key(crypto.Keccak256Hash(p))
-
-			var wg sync.WaitGroup
-			wg.Add(2)
-
-			go func(k Key, p []byte) {
-				result := cl.Get(k)
-				wg.Done()
-				expected := preimageByHash[k.PreimageKey()]
-				require.True(t, bytes.Equal(expected, result), "need correct preimage %x, got %x", expected, result)
-			}(k, p)
-
-			go func() {
-				err := srv.NextPreimageRequest(func(key common.Hash) ([]byte, error) {
-					dat, ok := preimageByHash[key]
-					if !ok {
-						return nil, fmt.Errorf("cannot find %s", key)
-					}
-					return dat, nil
-				})
-				wg.Done()
-				require.NoError(t, err)
-			}()
-			wg.Wait()
-		}
-	}
-	t.Run("empty preimage", func(t *testing.T) {
-		testPreimage([]byte{})
-	})
-	t.Run("nil preimage", func(t *testing.T) {
-		testPreimage(nil)
-	})
-	t.Run("zero", func(t *testing.T) {
-		testPreimage([]byte{0})
-	})
-	t.Run("multiple", func(t *testing.T) {
-		testPreimage([]byte("tx from alice"), []byte{0x13, 0x37}, []byte("tx from bob"))
-	})
-	t.Run("zeroes", func(t *testing.T) {
-		testPreimage(make([]byte, 1000))
-	})
-	t.Run("random", func(t *testing.T) {
-		dat := make([]byte, 1000)
-		_, _ = rand.Read(dat[:])
-		testPreimage(dat)
-	})
-}