// buf[m] = hash(cnt++ || buf[m] || buf[other])
// # Extract output from buffer.
// return buf[sCost-1]
-func B(h hash.Hash, passwd, salt []byte, sCost, tCost int) []byte {
+func B(h hash.Hash, passwd, salt []byte, sCost, tCost uint64) []byte {
var cnt uint64
intBuf := make([]byte, 8)
- buf := make([][]byte, sCost)
+ hSize := uint64(h.Size())
+ buf := make([]byte, 0, sCost*hSize)
// Expand input into buffer
binary.BigEndian.PutUint64(intBuf, cnt)
cnt++
h.Write(intBuf)
h.Write(passwd)
h.Write(salt)
- buf[0] = h.Sum(nil)
- var m int
+ buf = h.Sum(buf)
+ var m uint64
for m = 1; m < sCost; m++ {
binary.BigEndian.PutUint64(intBuf, cnt)
cnt++
h.Reset()
h.Write(intBuf)
- h.Write(buf[m-1])
- buf[m] = h.Sum(nil)
+ h.Write(buf[(m-1)*hSize : m*hSize])
+ buf = h.Sum(buf)
}
// Mix buffer contents
var prev []byte
- var i int
+ var i uint64
+ var neigh uint64
bi := big.NewInt(0)
bs := big.NewInt(int64(sCost))
biBuf := make([]byte, 0, h.Size())
- var other int
- for t := 0; t < tCost; t++ {
+ for t := uint64(0); t < tCost; t++ {
for m = 0; m < sCost; m++ {
// Hash last and current blocks
if m == 0 {
- prev = buf[len(buf)-1]
+ prev = buf[(sCost-1)*hSize:]
} else {
- prev = buf[m-1]
+ prev = buf[(m-1)*hSize : m*hSize]
}
binary.BigEndian.PutUint64(intBuf, cnt)
cnt++
h.Reset()
h.Write(intBuf)
h.Write(prev)
- h.Write(buf[m])
- buf[m] = h.Sum(buf[m][:0])
+ h.Write(buf[m*hSize : (m+1)*hSize])
+ buf = h.Sum(buf[:m*hSize])
// Hash in pseudorandomly chosen blocks
for i = 0; i < delta; i++ {
h.Reset()
h.Write(intBuf)
h.Write(salt)
- binary.BigEndian.PutUint64(intBuf, uint64(t))
+ binary.BigEndian.PutUint64(intBuf, t)
h.Write(intBuf)
- binary.BigEndian.PutUint64(intBuf, uint64(m))
+ binary.BigEndian.PutUint64(intBuf, m)
h.Write(intBuf)
- binary.BigEndian.PutUint64(intBuf, uint64(i))
+ binary.BigEndian.PutUint64(intBuf, i)
h.Write(intBuf)
biBuf = h.Sum(biBuf[:0])
bi.SetBytes(biBuf)
bi.Mod(bi, bs)
- other = int(bi.Uint64())
binary.BigEndian.PutUint64(intBuf, cnt)
cnt++
h.Reset()
h.Write(intBuf)
- h.Write(buf[m])
- h.Write(buf[other])
- buf[m] = h.Sum(buf[m][:0])
+ h.Write(buf[m*hSize : (m+1)*hSize])
+ neigh = bi.Uint64()
+ h.Write(buf[neigh*hSize : (neigh+1)*hSize])
+ buf = h.Sum(buf[:m*hSize])
}
}
}
// Extract output from buffer
- return buf[sCost-1]
+ return buf[(sCost-1)*hSize:]
}
// This function adds additional functionality over pure B(): ability to