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Updated ethash

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This commit is contained in:
obscuren
2015-03-14 16:42:05 +01:00
parent 387f6bba3e
commit 95711bc2dd
30 changed files with 1254 additions and 597 deletions
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296
Godeps/_workspace/src/github.com/ethereum/ethash/ethash.go generated vendored
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@@ -1,3 +1,13 @@
/*
###################################################################################
###################################################################################
#################### ####################
#################### EDIT AND YOU SHALL FEEL MY WRATH - jeff ####################
#################### ####################
###################################################################################
###################################################################################
*/
package ethash
/*
@@ -11,8 +21,8 @@ import "C"
import (
"bytes"
"encoding/binary"
"fmt"
"io/ioutil"
"log"
"math/big"
"math/rand"
"os"
@@ -21,25 +31,26 @@ import (
"time"
"unsafe"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/pow"
)
var tt256 = new(big.Int).Exp(big.NewInt(2), big.NewInt(256), big.NewInt(0))
var minDifficulty = new(big.Int).Exp(big.NewInt(2), big.NewInt(256), big.NewInt(0))
var powlogger = logger.NewLogger("POW")
type DAG struct {
SeedBlockNum uint64
dag unsafe.Pointer // full GB of memory for dag
file bool
type ParamsAndCache struct {
params *C.ethash_params
cache *C.ethash_cache
Epoch uint64
}
type ParamsAndCache struct {
params *C.ethash_params
cache *C.ethash_cache
SeedBlockNum uint64
type DAG struct {
dag unsafe.Pointer // full GB of memory for dag
file bool
paramsAndCache *ParamsAndCache
}
type Ethash struct {
@@ -48,10 +59,9 @@ type Ethash struct {
chainManager pow.ChainManager
dag *DAG
paramsAndCache *ParamsAndCache
nextdag unsafe.Pointer
ret *C.ethash_return_value
dagMutex *sync.Mutex
cacheMutex *sync.Mutex
dagMutex *sync.RWMutex
cacheMutex *sync.RWMutex
}
func parseNonce(nonce []byte) (uint64, error) {
@@ -65,151 +75,212 @@ func parseNonce(nonce []byte) (uint64, error) {
const epochLength uint64 = 30000
func GetSeedBlockNum(blockNum uint64) uint64 {
var seedBlockNum uint64 = 0
if blockNum > epochLength {
seedBlockNum = ((blockNum - 1) / epochLength) * epochLength
func makeParamsAndCache(chainManager pow.ChainManager, blockNum uint64) (*ParamsAndCache, error) {
if blockNum >= epochLength*2048 {
return nil, fmt.Errorf("block number is out of bounds (value %v, limit is %v)", blockNum, epochLength*2048)
}
return seedBlockNum
}
/*
XXX THIS DOESN'T WORK!! NEEDS FIXING
blockEpoch will underflow and wrap around causing massive issues
func GetSeedBlockNum(blockNum uint64) uint64 {
var seedBlockNum uint64 = 0
if blockNum > epochLength {
seedBlockNum = ((blockNum - 1) / epochLength) * epochLength
}
return seedBlockNum
}
*/
func makeParamsAndCache(chainManager pow.ChainManager, blockNum uint64) *ParamsAndCache {
seedBlockNum := GetSeedBlockNum(blockNum)
paramsAndCache := &ParamsAndCache{
params: new(C.ethash_params),
cache: new(C.ethash_cache),
SeedBlockNum: seedBlockNum,
params: new(C.ethash_params),
cache: new(C.ethash_cache),
Epoch: blockNum / epochLength,
}
C.ethash_params_init(paramsAndCache.params, C.uint32_t(seedBlockNum))
C.ethash_params_init(paramsAndCache.params, C.uint32_t(uint32(blockNum)))
paramsAndCache.cache.mem = C.malloc(paramsAndCache.params.cache_size)
seedHash := chainManager.GetBlockByNumber(seedBlockNum).SeedHash()
log.Println("Making Cache")
seedHash, err := GetSeedHash(blockNum)
if err != nil {
return nil, err
}
powlogger.Infoln("Making Cache")
start := time.Now()
C.ethash_mkcache(paramsAndCache.cache, paramsAndCache.params, (*C.uint8_t)(unsafe.Pointer(&seedHash[0])))
log.Println("Took:", time.Since(start))
powlogger.Infoln("Took:", time.Since(start))
return paramsAndCache
return paramsAndCache, nil
}
func (pow *Ethash) updateCache() {
func (pow *Ethash) UpdateCache(force bool) error {
pow.cacheMutex.Lock()
seedNum := GetSeedBlockNum(pow.chainManager.CurrentBlock().NumberU64())
if pow.paramsAndCache.SeedBlockNum != seedNum {
pow.paramsAndCache = makeParamsAndCache(pow.chainManager, pow.chainManager.CurrentBlock().NumberU64())
thisEpoch := pow.chainManager.CurrentBlock().NumberU64()
if force || pow.paramsAndCache.Epoch != thisEpoch {
var err error
pow.paramsAndCache, err = makeParamsAndCache(pow.chainManager, pow.chainManager.CurrentBlock().NumberU64())
if err != nil {
panic(err)
}
}
pow.cacheMutex.Unlock()
return nil
}
func makeDAG(p *ParamsAndCache) *DAG {
d := &DAG{
dag: C.malloc(p.params.full_size),
SeedBlockNum: p.SeedBlockNum,
dag: C.malloc(p.params.full_size),
file: false,
paramsAndCache: p,
}
donech := make(chan string)
go func() {
t := time.NewTicker(5 * time.Second)
tstart := time.Now()
done:
for {
select {
case <-t.C:
powlogger.Infof("... still generating DAG (%v) ...\n", time.Since(tstart).Seconds())
case str := <-donech:
powlogger.Infof("... %s ...\n", str)
break done
}
}
}()
C.ethash_compute_full_data(d.dag, p.params, p.cache)
donech <- "DAG generation completed"
return d
}
func (pow *Ethash) writeDagToDisk(dag *DAG, seedNum uint64) *os.File {
data := C.GoBytes(unsafe.Pointer(dag.dag), C.int(pow.paramsAndCache.params.full_size))
func (pow *Ethash) writeDagToDisk(dag *DAG, epoch uint64) *os.File {
if epoch > 2048 {
panic(fmt.Errorf("Epoch must be less than 2048 (is %v)", epoch))
}
data := C.GoBytes(unsafe.Pointer(dag.dag), C.int(dag.paramsAndCache.params.full_size))
file, err := os.Create("/tmp/dag")
if err != nil {
panic(err)
}
num := make([]byte, 8)
binary.BigEndian.PutUint64(num, seedNum)
dataEpoch := make([]byte, 8)
binary.BigEndian.PutUint64(dataEpoch, epoch)
file.Write(num)
file.Write(dataEpoch)
file.Write(data)
return file
}
func (pow *Ethash) UpdateDAG() {
pow.cacheMutex.Lock()
pow.dagMutex.Lock()
blockNum := pow.chainManager.CurrentBlock().NumberU64()
if blockNum >= epochLength*2048 {
// This will crash in the 2030s or 2040s
panic(fmt.Errorf("Current block number is out of bounds (value %v, limit is %v)", blockNum, epochLength*2048))
}
seedNum := GetSeedBlockNum(pow.chainManager.CurrentBlock().NumberU64())
if pow.dag == nil || pow.dag.SeedBlockNum != seedNum {
pow.dagMutex.Lock()
defer pow.dagMutex.Unlock()
thisEpoch := blockNum / epochLength
if pow.dag == nil || pow.dag.paramsAndCache.Epoch != thisEpoch {
if pow.dag != nil && pow.dag.dag != nil {
C.free(pow.dag.dag)
pow.dag.dag = nil
}
if pow.dag != nil && pow.dag.paramsAndCache.cache.mem != nil {
C.free(pow.dag.paramsAndCache.cache.mem)
pow.dag.paramsAndCache.cache.mem = nil
}
// Make the params and cache for the DAG
paramsAndCache, err := makeParamsAndCache(pow.chainManager, blockNum)
if err != nil {
panic(err)
}
// TODO: On non-SSD disks, loading the DAG from disk takes longer than generating it in memory
pow.paramsAndCache = paramsAndCache
path := path.Join("/", "tmp", "dag")
pow.dag = nil
log.Println("Generating dag")
powlogger.Infoln("Retrieving DAG")
start := time.Now()
file, err := os.Open(path)
if err != nil {
log.Printf("No dag found in '%s'. Generating new dago(takes a while)...", path)
pow.dag = makeDAG(pow.paramsAndCache)
file = pow.writeDagToDisk(pow.dag, seedNum)
powlogger.Infof("No DAG found. Generating new DAG in '%s' (this takes a while)...\n", path)
pow.dag = makeDAG(paramsAndCache)
file = pow.writeDagToDisk(pow.dag, thisEpoch)
pow.dag.file = true
} else {
data, err := ioutil.ReadAll(file)
if err != nil {
panic(err)
powlogger.Infof("DAG load err: %v\n", err)
}
num := binary.BigEndian.Uint64(data[0:8])
if num < seedNum {
log.Printf("Old found. Generating new dag (takes a while)...")
pow.dag = makeDAG(pow.paramsAndCache)
file = pow.writeDagToDisk(pow.dag, seedNum)
if len(data) < 8 {
powlogger.Infof("DAG in '%s' is less than 8 bytes, it must be corrupted. Generating new DAG (this takes a while)...\n", path)
pow.dag = makeDAG(paramsAndCache)
file = pow.writeDagToDisk(pow.dag, thisEpoch)
pow.dag.file = true
} else {
data = data[8:]
pow.dag = &DAG{
dag: unsafe.Pointer(&data[0]),
file: true,
SeedBlockNum: pow.paramsAndCache.SeedBlockNum,
dataEpoch := binary.BigEndian.Uint64(data[0:8])
if dataEpoch < thisEpoch {
powlogger.Infof("DAG in '%s' is stale. Generating new DAG (this takes a while)...\n", path)
pow.dag = makeDAG(paramsAndCache)
file = pow.writeDagToDisk(pow.dag, thisEpoch)
pow.dag.file = true
} else if dataEpoch > thisEpoch {
// FIXME
panic(fmt.Errorf("Saved DAG in '%s' reports to be from future epoch %v (current epoch is %v)\n", path, dataEpoch, thisEpoch))
} else if len(data) != (int(paramsAndCache.params.full_size) + 8) {
powlogger.Infof("DAG in '%s' is corrupted. Generating new DAG (this takes a while)...\n", path)
pow.dag = makeDAG(paramsAndCache)
file = pow.writeDagToDisk(pow.dag, thisEpoch)
pow.dag.file = true
} else {
data = data[8:]
pow.dag = &DAG{
dag: unsafe.Pointer(&data[0]),
file: true,
paramsAndCache: paramsAndCache,
}
}
}
}
log.Println("Took:", time.Since(start))
powlogger.Infoln("Took:", time.Since(start))
file.Close()
}
pow.dagMutex.Unlock()
pow.cacheMutex.Unlock()
}
func New(chainManager pow.ChainManager) *Ethash {
paramsAndCache, err := makeParamsAndCache(chainManager, chainManager.CurrentBlock().NumberU64())
if err != nil {
panic(err)
}
return &Ethash{
turbo: true,
paramsAndCache: makeParamsAndCache(chainManager, chainManager.CurrentBlock().NumberU64()),
paramsAndCache: paramsAndCache,
chainManager: chainManager,
dag: nil,
cacheMutex: new(sync.Mutex),
dagMutex: new(sync.Mutex),
cacheMutex: new(sync.RWMutex),
dagMutex: new(sync.RWMutex),
}
}
func (pow *Ethash) DAGSize() uint64 {
return uint64(pow.paramsAndCache.params.full_size)
return uint64(pow.dag.paramsAndCache.params.full_size)
}
func (pow *Ethash) CacheSize() uint64 {
return uint64(pow.paramsAndCache.params.cache_size)
}
func (pow *Ethash) GetSeedHash(blockNum uint64) []byte {
seednum := GetSeedBlockNum(blockNum)
return pow.chainManager.GetBlockByNumber(seednum).SeedHash()
func GetSeedHash(blockNum uint64) ([]byte, error) {
if blockNum >= epochLength*2048 {
return nil, fmt.Errorf("block number is out of bounds (value %v, limit is %v)", blockNum, epochLength*2048)
}
epoch := blockNum / epochLength
seedHash := make([]byte, 32)
var i uint64
for i = 0; i < 32; i++ {
seedHash[i] = 0
}
for i = 0; i < epoch; i++ {
seedHash = crypto.Sha3(seedHash)
}
return seedHash, nil
}
func (pow *Ethash) Stop() {
@@ -224,17 +295,18 @@ func (pow *Ethash) Stop() {
if pow.dag.dag != nil && !pow.dag.file {
C.free(pow.dag.dag)
}
if pow.dag != nil && pow.dag.paramsAndCache != nil && pow.dag.paramsAndCache.cache.mem != nil {
C.free(pow.dag.paramsAndCache.cache.mem)
pow.dag.paramsAndCache.cache.mem = nil
}
pow.dag.dag = nil
}
func (pow *Ethash) Search(block pow.Block, stop <-chan struct{}) (uint64, []byte, []byte) {
//pow.UpdateDAG()
pow.UpdateDAG()
// Not very elegant, multiple mining instances are not supported
//pow.dagMutex.Lock()
//pow.cacheMutex.Lock()
//defer pow.cacheMutex.Unlock()
//defer pow.dagMutex.Unlock()
pow.dagMutex.RLock()
defer pow.dagMutex.RUnlock()
r := rand.New(rand.NewSource(time.Now().UnixNano()))
miningHash := block.HashNoNonce()
@@ -246,7 +318,7 @@ func (pow *Ethash) Search(block pow.Block, stop <-chan struct{}) (uint64, []byte
nonce := uint64(r.Int63())
cMiningHash := (*C.uint8_t)(unsafe.Pointer(&miningHash[0]))
target := new(big.Int).Div(tt256, diff)
target := new(big.Int).Div(minDifficulty, diff)
var ret C.ethash_return_value
for {
@@ -262,14 +334,17 @@ func (pow *Ethash) Search(block pow.Block, stop <-chan struct{}) (uint64, []byte
hashes := ((float64(1e9) / float64(elapsed)) * float64(i-starti)) / 1000
pow.HashRate = int64(hashes)
C.ethash_full(&ret, pow.dag.dag, pow.paramsAndCache.params, cMiningHash, C.uint64_t(nonce))
C.ethash_full(&ret, pow.dag.dag, pow.dag.paramsAndCache.params, cMiningHash, C.uint64_t(nonce))
result := ethutil.Bytes2Big(C.GoBytes(unsafe.Pointer(&ret.result[0]), C.int(32)))
// TODO: disagrees with the spec https://github.com/ethereum/wiki/wiki/Ethash#mining
if result.Cmp(target) <= 0 {
mixDigest := C.GoBytes(unsafe.Pointer(&ret.mix_hash[0]), C.int(32))
return nonce, mixDigest, pow.GetSeedHash(block.NumberU64())
seedHash, err := GetSeedHash(block.NumberU64()) // This seedhash is useless
if err != nil {
panic(err)
}
return nonce, mixDigest, seedHash
}
nonce += 1
@@ -283,32 +358,41 @@ func (pow *Ethash) Search(block pow.Block, stop <-chan struct{}) (uint64, []byte
}
func (pow *Ethash) Verify(block pow.Block) bool {
// Make sure the SeedHash is set correctly
if bytes.Compare(block.SeedHash(), pow.GetSeedHash(block.NumberU64())) != 0 {
return false
}
return pow.verify(block.HashNoNonce(), block.MixDigest(), block.Difficulty(), block.NumberU64(), block.Nonce())
}
func (pow *Ethash) verify(hash []byte, mixDigest []byte, difficulty *big.Int, blockNum uint64, nonce uint64) bool {
// First check: make sure header, mixDigest, nonce are correct without hitting the DAG
// Make sure the block num is valid
if blockNum >= epochLength*2048 {
powlogger.Infoln(fmt.Sprintf("Block number exceeds limit, invalid (value is %v, limit is %v)",
blockNum, epochLength*2048))
return false
}
// First check: make sure header, mixDigest, nonce are correct without hitting the cache
// This is to prevent DOS attacks
chash := (*C.uint8_t)(unsafe.Pointer(&hash[0]))
cnonce := C.uint64_t(nonce)
target := new(big.Int).Div(tt256, difficulty)
target := new(big.Int).Div(minDifficulty, difficulty)
var pAc *ParamsAndCache
// If its an old block (doesn't use the current cache)
// get the cache for it but don't update (so we don't need the mutex)
// Otherwise, it's the current block or a future.
// Otherwise, it's the current block or a future block.
// If current, updateCache will do nothing.
if GetSeedBlockNum(blockNum) < pow.paramsAndCache.SeedBlockNum {
pAc = makeParamsAndCache(pow.chainManager, blockNum)
if blockNum/epochLength < pow.paramsAndCache.Epoch {
var err error
// If we can't make the params for some reason, this block is invalid
pAc, err = makeParamsAndCache(pow.chainManager, blockNum)
if err != nil {
powlogger.Infoln(err)
return false
}
} else {
pow.updateCache()
pow.cacheMutex.Lock()
defer pow.cacheMutex.Unlock()
pow.UpdateCache(false)
pow.cacheMutex.RLock()
defer pow.cacheMutex.RUnlock()
pAc = pow.paramsAndCache
}