Support obfuscated2

mtglib/internal/obfuscated2/pools.go

@@ -0,0 +1,22 @@
+package obfuscated2
+
+import (
+	"crypto/sha256"
+	"hash"
+	"sync"
+)
+
+var sha256HasherPool = sync.Pool{
+	New: func() interface{} {
+		return sha256.New()
+	},
+}
+
+func acquireSha256Hasher() hash.Hash {
+	return sha256HasherPool.Get().(hash.Hash)
+}
+
+func releaseSha256Hasher(h hash.Hash) {
+	h.Reset()
+	sha256HasherPool.Put(h)
+}