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Merge branch 'Gustav-Simonsson-align_key_and_ecdsa_nonce_entropy' int…
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…o develop
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obscuren committed Feb 13, 2015
2 parents 95cfaa1 + 12b2d57 commit 49a739c
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Showing 6 changed files with 105 additions and 125 deletions.
15 changes: 3 additions & 12 deletions crypto/key_store_passphrase.go
Original file line number Diff line number Diff line change
Expand Up @@ -68,10 +68,10 @@ import (
"code.google.com/p/go.crypto/scrypt"
"crypto/aes"
"crypto/cipher"
crand "crypto/rand"
"encoding/hex"
"encoding/json"
"errors"
"github.com/ethereum/go-ethereum/crypto/randentropy"
"io"
"os"
"path"
Expand Down Expand Up @@ -116,7 +116,7 @@ func (ks keyStorePassphrase) GetKeyAddresses() (addresses [][]byte, err error) {

func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
authArray := []byte(auth)
salt := GetEntropyCSPRNG(32)
salt := randentropy.GetEntropyMixed(32)
derivedKey, err := scrypt.Key(authArray, salt, scryptN, scryptr, scryptp, scryptdkLen)
if err != nil {
return err
Expand All @@ -131,7 +131,7 @@ func (ks keyStorePassphrase) StoreKey(key *Key, auth string) (err error) {
return err
}

iv := GetEntropyCSPRNG(aes.BlockSize) // 16
iv := randentropy.GetEntropyMixed(aes.BlockSize) // 16
AES256CBCEncrypter := cipher.NewCBCEncrypter(AES256Block, iv)
cipherText := make([]byte, len(toEncrypt))
AES256CBCEncrypter.CryptBlocks(cipherText, toEncrypt)
Expand Down Expand Up @@ -196,12 +196,3 @@ func DecryptKey(ks keyStorePassphrase, keyAddr []byte, auth string) (keyBytes []
}
return keyBytes, keyId, err
}

func GetEntropyCSPRNG(n int) []byte {
mainBuff := make([]byte, n)
_, err := io.ReadFull(crand.Reader, mainBuff)
if err != nil {
panic("key generation: reading from crypto/rand failed: " + err.Error())
}
return mainBuff
}
8 changes: 4 additions & 4 deletions crypto/key_store_test.go
Original file line number Diff line number Diff line change
@@ -1,15 +1,15 @@
package crypto

import (
crand "crypto/rand"
"github.com/ethereum/go-ethereum/crypto/randentropy"
"reflect"
"testing"
)

func TestKeyStorePlain(t *testing.T) {
ks := NewKeyStorePlain(DefaultDataDir())
pass := "" // not used but required by API
k1, err := ks.GenerateNewKey(crand.Reader, pass)
k1, err := ks.GenerateNewKey(randentropy.Reader, pass)
if err != nil {
t.Fatal(err)
}
Expand Down Expand Up @@ -37,7 +37,7 @@ func TestKeyStorePlain(t *testing.T) {
func TestKeyStorePassphrase(t *testing.T) {
ks := NewKeyStorePassphrase(DefaultDataDir())
pass := "foo"
k1, err := ks.GenerateNewKey(crand.Reader, pass)
k1, err := ks.GenerateNewKey(randentropy.Reader, pass)
if err != nil {
t.Fatal(err)
}
Expand All @@ -63,7 +63,7 @@ func TestKeyStorePassphrase(t *testing.T) {
func TestKeyStorePassphraseDecryptionFail(t *testing.T) {
ks := NewKeyStorePassphrase(DefaultDataDir())
pass := "foo"
k1, err := ks.GenerateNewKey(crand.Reader, pass)
k1, err := ks.GenerateNewKey(randentropy.Reader, pass)
if err != nil {
t.Fatal(err)
}
Expand Down
84 changes: 84 additions & 0 deletions crypto/randentropy/rand_entropy.go
Original file line number Diff line number Diff line change
@@ -0,0 +1,84 @@
package randentropy

import (
crand "crypto/rand"
"encoding/binary"
"github.com/ethereum/go-ethereum/crypto/sha3"
"io"
"os"
"strings"
"time"
)

var Reader io.Reader = &randEntropy{}

type randEntropy struct {
}

func (*randEntropy) Read(bytes []byte) (n int, err error) {
readBytes := GetEntropyMixed(len(bytes))
copy(bytes, readBytes)
return len(bytes), nil
}

// TODO: copied from crypto.go , move to sha3 package?
func Sha3(data []byte) []byte {
d := sha3.NewKeccak256()
d.Write(data)

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)
if err != nil {
panic("reading from crypto/rand failed: " + err.Error())
}
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
}
5 changes: 3 additions & 2 deletions crypto/secp256k1/secp256.go
Original file line number Diff line number Diff line change
Expand Up @@ -15,6 +15,7 @@ import "C"
import (
"bytes"
"errors"
"github.com/ethereum/go-ethereum/crypto/randentropy"
"unsafe"
)

Expand Down Expand Up @@ -68,7 +69,7 @@ func GenerateKeyPair() ([]byte, []byte) {
const seckey_len = 32

var pubkey []byte = make([]byte, pubkey_len)
var seckey []byte = RandByte(seckey_len)
var seckey []byte = randentropy.GetEntropyMixed(seckey_len)

var pubkey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&pubkey[0]))
var seckey_ptr *C.uchar = (*C.uchar)(unsafe.Pointer(&seckey[0]))
Expand Down Expand Up @@ -124,7 +125,7 @@ int secp256k1_ecdsa_sign_compact(const unsigned char *msg, int msglen,
*/

func Sign(msg []byte, seckey []byte) ([]byte, error) {
nonce := RandByte(32)
nonce := randentropy.GetEntropyMixed(32)

var sig []byte = make([]byte, 65)
var recid C.int
Expand Down
97 changes: 0 additions & 97 deletions crypto/secp256k1/secp256_rand.go

This file was deleted.

21 changes: 11 additions & 10 deletions crypto/secp256k1/secp256_test.go
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@ package secp256k1
import (
"bytes"
"fmt"
"github.com/ethereum/go-ethereum/crypto/randentropy"
"log"
"testing"
)
Expand All @@ -12,7 +13,7 @@ const SigSize = 65 //64+1

func Test_Secp256_00(t *testing.T) {

var nonce []byte = RandByte(32) //going to get bitcoins stolen!
var nonce []byte = randentropy.GetEntropyMixed(32) //going to get bitcoins stolen!

if len(nonce) != 32 {
t.Fatal()
Expand Down Expand Up @@ -50,7 +51,7 @@ func Test_Secp256_01(t *testing.T) {
//test size of messages
func Test_Secp256_02s(t *testing.T) {
pubkey, seckey := GenerateKeyPair()
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)
if sig == nil {
Expand All @@ -73,7 +74,7 @@ func Test_Secp256_02s(t *testing.T) {
//test signing message
func Test_Secp256_02(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey)
if sig == nil {
t.Fatal("Signature nil")
Expand All @@ -96,7 +97,7 @@ func Test_Secp256_02(t *testing.T) {
//test pubkey recovery
func Test_Secp256_02a(t *testing.T) {
pubkey1, seckey1 := GenerateKeyPair()
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey1)

if sig == nil {
Expand Down Expand Up @@ -125,7 +126,7 @@ func Test_Secp256_02a(t *testing.T) {
func Test_Secp256_03(t *testing.T) {
_, seckey := GenerateKeyPair()
for i := 0; i < TESTS; i++ {
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)

Expand All @@ -141,7 +142,7 @@ func Test_Secp256_03(t *testing.T) {
func Test_Secp256_04(t *testing.T) {
for i := 0; i < TESTS; i++ {
pubkey1, seckey := GenerateKeyPair()
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey)
CompactSigTest(sig)

Expand All @@ -164,15 +165,15 @@ func Test_Secp256_04(t *testing.T) {
// -SIPA look at this

func randSig() []byte {
sig := RandByte(65)
sig := randentropy.GetEntropyMixed(65)
sig[32] &= 0x70
sig[64] %= 4
return sig
}

func Test_Secp256_06a_alt0(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey)

if sig == nil {
Expand Down Expand Up @@ -203,12 +204,12 @@ func Test_Secp256_06a_alt0(t *testing.T) {

func Test_Secp256_06b(t *testing.T) {
pubkey1, seckey := GenerateKeyPair()
msg := RandByte(32)
msg := randentropy.GetEntropyMixed(32)
sig, _ := Sign(msg, seckey)

fail_count := 0
for i := 0; i < TESTS; i++ {
msg = RandByte(32)
msg = randentropy.GetEntropyMixed(32)
pubkey2, _ := RecoverPubkey(msg, sig)
if bytes.Equal(pubkey1, pubkey2) == true {
t.Fail()
Expand Down

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