github.com/zhiqiangxu/go-ethereum@v1.9.16-0.20210824055606-be91cfdebc48/core/types/bloom9.go (about) 1 // Copyright 2014 The go-ethereum Authors 2 // This file is part of the go-ethereum library. 3 // 4 // The go-ethereum library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-ethereum library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. 16 17 package types 18 19 import ( 20 "fmt" 21 "math/big" 22 23 "github.com/zhiqiangxu/go-ethereum/common/hexutil" 24 "github.com/zhiqiangxu/go-ethereum/crypto" 25 ) 26 27 type bytesBacked interface { 28 Bytes() []byte 29 } 30 31 const ( 32 // BloomByteLength represents the number of bytes used in a header log bloom. 33 BloomByteLength = 256 34 35 // BloomBitLength represents the number of bits used in a header log bloom. 36 BloomBitLength = 8 * BloomByteLength 37 ) 38 39 // Bloom represents a 2048 bit bloom filter. 40 type Bloom [BloomByteLength]byte 41 42 // BytesToBloom converts a byte slice to a bloom filter. 43 // It panics if b is not of suitable size. 44 func BytesToBloom(b []byte) Bloom { 45 var bloom Bloom 46 bloom.SetBytes(b) 47 return bloom 48 } 49 50 // SetBytes sets the content of b to the given bytes. 51 // It panics if d is not of suitable size. 52 func (b *Bloom) SetBytes(d []byte) { 53 if len(b) < len(d) { 54 panic(fmt.Sprintf("bloom bytes too big %d %d", len(b), len(d))) 55 } 56 copy(b[BloomByteLength-len(d):], d) 57 } 58 59 // Add adds d to the filter. Future calls of Test(d) will return true. 60 func (b *Bloom) Add(d *big.Int) { 61 bin := new(big.Int).SetBytes(b[:]) 62 bin.Or(bin, bloom9(d.Bytes())) 63 b.SetBytes(bin.Bytes()) 64 } 65 66 // Big converts b to a big integer. 67 func (b Bloom) Big() *big.Int { 68 return new(big.Int).SetBytes(b[:]) 69 } 70 71 func (b Bloom) Bytes() []byte { 72 return b[:] 73 } 74 75 func (b Bloom) Test(test *big.Int) bool { 76 return BloomLookup(b, test) 77 } 78 79 func (b Bloom) TestBytes(test []byte) bool { 80 return b.Test(new(big.Int).SetBytes(test)) 81 82 } 83 84 // MarshalText encodes b as a hex string with 0x prefix. 85 func (b Bloom) MarshalText() ([]byte, error) { 86 return hexutil.Bytes(b[:]).MarshalText() 87 } 88 89 // UnmarshalText b as a hex string with 0x prefix. 90 func (b *Bloom) UnmarshalText(input []byte) error { 91 return hexutil.UnmarshalFixedText("Bloom", input, b[:]) 92 } 93 94 func CreateBloom(receipts Receipts) Bloom { 95 bin := new(big.Int) 96 for _, receipt := range receipts { 97 bin.Or(bin, LogsBloom(receipt.Logs)) 98 } 99 100 return BytesToBloom(bin.Bytes()) 101 } 102 103 func LogsBloom(logs []*Log) *big.Int { 104 bin := new(big.Int) 105 for _, log := range logs { 106 bin.Or(bin, bloom9(log.Address.Bytes())) 107 for _, b := range log.Topics { 108 bin.Or(bin, bloom9(b[:])) 109 } 110 } 111 112 return bin 113 } 114 115 func bloom9(b []byte) *big.Int { 116 b = crypto.Keccak256(b) 117 118 r := new(big.Int) 119 120 for i := 0; i < 6; i += 2 { 121 t := big.NewInt(1) 122 b := (uint(b[i+1]) + (uint(b[i]) << 8)) & 2047 123 r.Or(r, t.Lsh(t, b)) 124 } 125 126 return r 127 } 128 129 var Bloom9 = bloom9 130 131 func BloomLookup(bin Bloom, topic bytesBacked) bool { 132 bloom := bin.Big() 133 cmp := bloom9(topic.Bytes()) 134 135 return bloom.And(bloom, cmp).Cmp(cmp) == 0 136 }