Remove the awesome, ever misunderstood entropy mixing

This commit is contained in:
Gustav Simonsson 2015-04-02 17:02:56 +02:00
parent 58d6ec689f
commit 9918b6c84e
4 changed files with 15 additions and 64 deletions

@ -118,7 +118,7 @@ func (ks keyStorePassphrase) GetKeyAddresses() (addresses [][]byte, err error) {
func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
authArray := []byte(auth)
salt := randentropy.GetEntropyMixed(32)
salt := randentropy.GetEntropyCSPRNG(32)
derivedKey, err := scrypt.Key(authArray, salt, scryptN, scryptr, scryptp, scryptdkLen)
if err != nil {
return err
@ -133,7 +133,7 @@ func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
return err
}
iv := randentropy.GetEntropyMixed(aes.BlockSize) // 16
iv := randentropy.GetEntropyCSPRNG(aes.BlockSize) // 16
AES256CBCEncrypter := cipher.NewCBCEncrypter(AES256Block, iv)
cipherText := make([]byte, len(toEncrypt))
AES256CBCEncrypter.CryptBlocks(cipherText, toEncrypt)

@ -2,12 +2,8 @@ package randentropy
import (
crand "crypto/rand"
"encoding/binary"
"github.com/ethereum/go-ethereum/crypto/sha3"
"io"
"os"
"strings"
"time"
)
var Reader io.Reader = &randEntropy{}
@ -16,7 +12,7 @@ type randEntropy struct {
}
func (*randEntropy) Read(bytes []byte) (n int, err error) {
readBytes := GetEntropyMixed(len(bytes))
readBytes := GetEntropyCSPRNG(len(bytes))
copy(bytes, readBytes)
return len(bytes), nil
}
@ -29,40 +25,6 @@ func Sha3(data []byte) []byte {
return d.Sum(nil)
}
// TODO: verify. this needs to be audited
// we start with crypt/rand, then XOR in additional entropy from OS
func GetEntropyMixed(n int) []byte {
startTime := time.Now().UnixNano()
// for each source, we take SHA3 of the source and use it as seed to math/rand
// then read bytes from it and XOR them onto the bytes read from crypto/rand
mainBuff := GetEntropyCSPRNG(n)
// 1. OS entropy sources
startTimeBytes := make([]byte, 32)
binary.PutVarint(startTimeBytes, startTime)
startTimeHash := Sha3(startTimeBytes)
mixBytes(mainBuff, startTimeHash)
pid := os.Getpid()
pidBytes := make([]byte, 32)
binary.PutUvarint(pidBytes, uint64(pid))
pidHash := Sha3(pidBytes)
mixBytes(mainBuff, pidHash)
osEnv := os.Environ()
osEnvBytes := []byte(strings.Join(osEnv, ""))
osEnvHash := Sha3(osEnvBytes)
mixBytes(mainBuff, osEnvHash)
// not all OS have hostname in env variables
osHostName, err := os.Hostname()
if err != nil {
osHostNameBytes := []byte(osHostName)
osHostNameHash := Sha3(osHostNameBytes)
mixBytes(mainBuff, osHostNameHash)
}
return mainBuff
}
func GetEntropyCSPRNG(n int) []byte {
mainBuff := make([]byte, n)
_, err := io.ReadFull(crand.Reader, mainBuff)
@ -71,14 +33,3 @@ func GetEntropyCSPRNG(n int) []byte {
}
return mainBuff
}
func mixBytes(buff []byte, mixBuff []byte) []byte {
bytesToMix := len(buff)
if bytesToMix > 32 {
bytesToMix = 32
}
for i := 0; i < bytesToMix; i++ {
buff[i] ^= mixBuff[i]
}
return buff
}

@ -59,7 +59,7 @@ func GenerateKeyPair() ([]byte, []byte) {
const seckey_len = 32
var pubkey []byte = make([]byte, pubkey_len)
var seckey []byte = randentropy.GetEntropyMixed(seckey_len)
var seckey []byte = randentropy.GetEntropyCSPRNG(seckey_len)
var pubkey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&pubkey[0]))
var seckey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&seckey[0]))
@ -99,7 +99,7 @@ func GeneratePubKey(seckey []byte) ([]byte, error) {
}
func Sign(msg []byte, seckey []byte) ([]byte, error) {
nonce := randentropy.GetEntropyMixed(32)
nonce := randentropy.GetEntropyCSPRNG(32)
var sig []byte = make([]byte, 65)
var recid C.int

@ -14,7 +14,7 @@ const SigSize = 65 //64+1
func Test_Secp256_00(t *testing.T) {
var nonce []byte = randentropy.GetEntropyMixed(32) //going to get bitcoins stolen!
var nonce []byte = randentropy.GetEntropyCSPRNG(32) //going to get bitcoins stolen!
if len(nonce) != 32 {
t.Fatal()
@ -52,7 +52,7 @@ func Test_Secp256_01(t *testing.T) {
//test size of messages
func Test_Secp256_02s(t *testing.T) {
pubkey, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
if sig == nil {
@ -75,7 +75,7 @@ func Test_Secp256_02s(t *testing.T) {
//test signing message
func Test_Secp256_02(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
if sig == nil {
t.Fatal("Signature nil")
@ -98,7 +98,7 @@ func Test_Secp256_02(t *testing.T) {
//test pubkey recovery
func Test_Secp256_02a(t *testing.T) {
pubkey1, seckey1 := GenerateKeyPair()
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey1)
if sig == nil {
@ -127,7 +127,7 @@ func Test_Secp256_02a(t *testing.T) {
func Test_Secp256_03(t *testing.T) {
_, seckey := GenerateKeyPair()
for i := 0; i < TESTS; i++ {
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
@ -143,7 +143,7 @@ func Test_Secp256_03(t *testing.T) {
func Test_Secp256_04(t *testing.T) {
for i := 0; i < TESTS; i++ {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
@ -166,7 +166,7 @@ func Test_Secp256_04(t *testing.T) {
// -SIPA look at this
func randSig() []byte {
sig := randentropy.GetEntropyMixed(65)
sig := randentropy.GetEntropyCSPRNG(65)
sig[32] &= 0x70
sig[64] %= 4
return sig
@ -174,7 +174,7 @@ func randSig() []byte {
func Test_Secp256_06a_alt0(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
if sig == nil {
@ -205,12 +205,12 @@ func Test_Secp256_06a_alt0(t *testing.T) {
func Test_Secp256_06b(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := randentropy.GetEntropyMixed(32)
msg := randentropy.GetEntropyCSPRNG(32)
sig, _ := Sign(msg, seckey)
fail_count := 0
for i := 0; i < TESTS; i++ {
msg = randentropy.GetEntropyMixed(32)
msg = randentropy.GetEntropyCSPRNG(32)
pubkey2, _ := RecoverPubkey(msg, sig)
if bytes.Equal(pubkey1, pubkey2) == true {
t.Fail()