ipld-eth-server/pkg/ipfs/ipld/shared.go

152 lines
4.0 KiB
Go

// VulcanizeDB
// Copyright © 2019 Vulcanize
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
package ipld
import (
"bytes"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core/rawdb"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/rlp"
"github.com/ethereum/go-ethereum/trie"
"github.com/ipfs/go-cid"
mh "github.com/multiformats/go-multihash"
)
// IPLD Codecs for Ethereum
// See the authoritative document:
// https://github.com/multiformats/multicodec/blob/master/table.csv
const (
RawBinary = 0x55
MEthHeader = 0x90
MEthHeaderList = 0x91
MEthTxTrie = 0x92
MEthTx = 0x93
MEthTxReceiptTrie = 0x94
MEthTxReceipt = 0x95
MEthStateTrie = 0x96
MEthAccountSnapshot = 0x97
MEthStorageTrie = 0x98
MBitcoinHeader = 0xb0
MBitcoinTx = 0xb1
)
// RawdataToCid takes the desired codec and a slice of bytes
// and returns the proper cid of the object.
func RawdataToCid(codec uint64, rawdata []byte, multiHash uint64) (cid.Cid, error) {
c, err := cid.Prefix{
Codec: codec,
Version: 1,
MhType: multiHash,
MhLength: -1,
}.Sum(rawdata)
if err != nil {
return cid.Cid{}, err
}
return c, nil
}
// keccak256ToCid takes a keccak256 hash and returns its cid based on
// the codec given.
func keccak256ToCid(codec uint64, h []byte) cid.Cid {
buf, err := mh.Encode(h, mh.KECCAK_256)
if err != nil {
panic(err)
}
return cid.NewCidV1(codec, mh.Multihash(buf))
}
// commonHashToCid takes a go-ethereum common.Hash and returns its
// cid based on the codec given,
func commonHashToCid(codec uint64, h common.Hash) cid.Cid {
mhash, err := mh.Encode(h[:], mh.KECCAK_256)
if err != nil {
panic(err)
}
return cid.NewCidV1(codec, mhash)
}
// sha256ToCid takes a sha246 hash and returns its cid based on the
// codec given
func sha256ToCid(codec uint64, h []byte) cid.Cid {
hash, err := mh.Encode(h, mh.DBL_SHA2_256)
if err != nil {
panic(err)
}
return cid.NewCidV1(codec, hash)
}
// getRLP encodes the given object to RLP returning its bytes.
func getRLP(object interface{}) []byte {
buf := new(bytes.Buffer)
if err := rlp.Encode(buf, object); err != nil {
panic(err)
}
return buf.Bytes()
}
// localTrie wraps a go-ethereum trie and its underlying memory db.
// It contributes to the creation of the trie node objects.
type localTrie struct {
keys [][]byte
db ethdb.Database
trie *trie.Trie
}
// newLocalTrie initializes and returns a localTrie object
func newLocalTrie() *localTrie {
var err error
lt := &localTrie{}
lt.db = rawdb.NewMemoryDatabase()
lt.trie, err = trie.New(common.Hash{}, trie.NewDatabase(lt.db))
if err != nil {
panic(err)
}
return lt
}
// add receives the index of an object and its rawdata value
// and includes it into the localTrie
func (lt *localTrie) add(idx int, rawdata []byte) {
key, err := rlp.EncodeToBytes(uint(idx))
if err != nil {
panic(err)
}
lt.keys = append(lt.keys, key)
if err := lt.db.Put(key, rawdata); err != nil {
panic(err)
}
lt.trie.Update(key, rawdata)
}
// rootHash returns the computed trie root.
// Useful for sanity checks on parsed data.
func (lt *localTrie) rootHash() []byte {
return lt.trie.Hash().Bytes()
}
// getKeys returns the stored keys of the memory database
// of the localTrie for further processing.
func (lt *localTrie) getKeys() [][]byte {
return lt.keys
}