From c4aec144256e3f27fedd8f8de03e10cc08eecab8 Mon Sep 17 00:00:00 2001 From: Mateusz Zalega Date: Thu, 22 Oct 2015 22:41:18 +0200 Subject: Initial --- crc32.cc | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 crc32.cc (limited to 'crc32.cc') diff --git a/crc32.cc b/crc32.cc new file mode 100644 index 0000000..558d4ef --- /dev/null +++ b/crc32.cc @@ -0,0 +1,37 @@ +/* + * Author: Copyright (C) Andrzej Surowiec 2012 + * + * + * This file is part of Nitrokey. + * + * Nitrokey is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * any later version. + * + * Nitrokey is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Nitrokey. If not, see . + */ + +#include "crc32.h" + + +uint32_t Crc32 (uint32_t Crc, uint32_t Data) +{ +int i; + + Crc = Crc ^ Data; + + for (i = 0; i < 32; i++) + if (Crc & 0x80000000) + Crc = (Crc << 1) ^ 0x04C11DB7; // Polynomial used in STM32 + else + Crc = (Crc << 1); + + return (Crc); +} -- cgit v1.2.1