func main() {  
    scmKey := decode(scmKey)
    salt := decode(salt)
 
    maskkey := pbkdf2.Key([]byte("password"), salt, rounds, 32, sha1.New)
 
    // AES-ECB-256_decrypt(k=maskkey, scm_key) = scr_key
    a, err := aes.NewCipher(maskkey)
    if err != nil {
        log.Fatal(err)
    }
    for i := 0; i < len(scmKey); i += a.BlockSize() {
        a.Decrypt(scmKey[i:i+a.BlockSize()], scmKey[i:i+a.BlockSize()])
    }
 
    // HMAC-SHA1(k=maskkey, scm_key) == sch_mac
    h := sha1.Sum(maskkey)
    mac := hmac.New(sha1.New, h[:])
    mac.Write(scmKey)
    expectedMAC := mac.Sum(nil)
 
    fmt.Print(hex.Dump(expectedMAC))
}