@@ -25,10 +25,12 @@
 #import "OFArray.h"
 #import "OFDictionary.h"
 #import "OFFile.h"
 #import "OFInflateStream.h"
 #import "OFInflate64Stream.h"
+
+#import "crc32.h"
 
 #import "OFChecksumFailedException.h"
 #import "OFInvalidArgumentException.h"
 #import "OFInvalidFormatException.h"
 #import "OFNotImplementedException.h"
@@ -36,12 +38,10 @@
 #import "OFOutOfRangeException.h"
 #import "OFReadFailedException.h"
 #import "OFSeekFailedException.h"
 #import "OFUnsupportedVersionException.h"
 
-#define CRC32_MAGIC 0xEDB88320
-
 /*
  * FIXME: Current limitations:
  *  - Split archives are not supported.
  *  - Write support is missing.
  *  - The ZIP has to be a file on the local file system.
@@ -114,23 +114,10 @@
 	*size -= 8;
 
 	return field;
 }
 
-static uint32_t
-calculateCRC32(uint32_t crc, uint8_t *bytes, size_t length)
-{
-	for (size_t i = 0; i < length; i++) {
-		crc ^= bytes[i];
-
-		for (uint8_t j = 0; j < 8; j++)
-			crc = (crc >> 1) ^ (CRC32_MAGIC & (~(crc & 1) + 1));
-	}
-
-	return crc;
-}
-
 static void
 seekOrThrowInvalidFormat(OFSeekableStream *stream,
     of_offset_t offset, int whence)
 {
 	@try {
@@ -561,15 +548,15 @@
 		ret = [_decompressedStream readIntoBuffer: buffer
 						   length: min];
 		_size -= ret;
 	}
 
-	_CRC32 = calculateCRC32(_CRC32, buffer, ret);
+	_CRC32 = of_crc32(_CRC32, buffer, ret);
 
 	return ret;
 }
 
 - (void)close
 {
 	_closed = true;
 }
 @end