pearson.go

func pearson(msg, iv []byte, bytecount int) []byte {
	var h byte
	hh := make([]byte, bytecount)
	for j := 0; j < bytecount; j++ {
		h = iv[(int(msg[0])+j)%256]
		for i := 1; i < len(msg); i++ {
			h = iv[h^msg[i]]
		}
		hh[j] = h
	}
	return hh
}

func scramble(seed []byte) []byte {
	ss := make([]byte, 256)
	for i := 0; i < 256; i++ {
		ss[i] = byte(i)
	}
	j := 0
	for i := 0; i < 256; i++ {
		j = (j + int(ss[i]) + int(seed[i%len(seed)])) % 256
		ss[i], ss[j] = ss[j], ss[i]
	}
	return ss
}