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paul-delange/TGDFileHash.c

Created October 3, 2013 11:26
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TGDFileHash.c
/*
* TGDFileHash.c
* TagAdA: Tagging Advanced Application
*
* Copyright © 2008-2010 The TagAdA Team. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
//---------------------------------------------------------
// Includes
//---------------------------------------------------------
// Header file
#include "TGDFileHash.h"
// Standard library
#include <stdint.h>
#include <stdio.h>
// Cryptography
#include <CommonCrypto/CommonDigest.h>
//---------------------------------------------------------
// Other declarations
//---------------------------------------------------------
#pragma mark -
#pragma mark Private types definitions
// Function pointer types for functions used in the computation
// of a cryptographic hash.
typedef int (*TGDHashInitFunction) (uint8_t *hashObjectPointer[]);
typedef int (*TGDHashUpdateFunction) (uint8_t *hashObjectPointer[],
const void *data,
CC_LONG len);
typedef int (*TGDHashFinalFunction) (unsigned char *md,
uint8_t *hashObjectPointer[]);
// Structure used to describe a hash computation context.
typedef struct _TGDHashComputationContext {
TGDHashInitFunction initFunction;
TGDHashUpdateFunction updateFunction;
TGDHashFinalFunction finalFunction;
size_t digestLength;
uint8_t **hashObjectPointer;
} TGDHashComputationContext;
#pragma mark -
#pragma mark Private functions declarations
static CFStringRef _TGDFileHashCreateWithPath(CFStringRef filePath,
size_t chunkSizeForReadingData,
TGDHashComputationContext *context);
typedef struct {
CC_LONG crc;
} CC_CRC32_CTX;
static int CC_CRC32_Init(CC_CRC32_CTX *c);
static int CC_CRC32_Update(CC_CRC32_CTX *c, const uint8_t *data, CC_LONG len);
static int CC_CRC32_Final(unsigned char *md, CC_CRC32_CTX *c);
#define CC_CRC32_DIGEST_LENGTH 4
#pragma mark -
#pragma mark Handy preprocessor macros
// From <CommonCrypto/CommonDigest.h>:
// - same context struct is used for SHA224 and SHA256;
// - same context struct is used for SHA384 and SHA512.
#define CC_SHA224_CTX CC_SHA256_CTX
#define CC_SHA384_CTX CC_SHA512_CTX
// Macro to easily setup a TGDHashComputationContext given
// a hash algorithm name.
#define TGDHashComputationContextDeclare(context, hashAlgorithmName) \
CC_##hashAlgorithmName##_CTX hashObjectFor##hashAlgorithmName; \
TGDHashComputationContext context = { \
(TGDHashInitFunction)&CC_##hashAlgorithmName##_Init, \
(TGDHashUpdateFunction)&CC_##hashAlgorithmName##_Update, \
(TGDHashFinalFunction)&CC_##hashAlgorithmName##_Final, \
CC_##hashAlgorithmName##_DIGEST_LENGTH, \
(uint8_t **)&hashObjectFor##hashAlgorithmName \
}
// Macro used in TGDFileHashCreateWithPath to easily add more cases
// to the switch block with just the hash algorithm name.
#define TGDFileHashCreateWithPath_CaseHashAlgorithmBranch( \
hashAlgorithmName \
) \
\
case TGDHashAlgorithm##hashAlgorithmName: \
do { \
TGDHashComputationContextDeclare(hashComputationContext, \
hashAlgorithmName); \
return _TGDFileHashCreateWithPath(filePath, \
chunkSizeForReadingData, \
&hashComputationContext); \
} while(false)
// Macro used in TGDFileHashCreateWithPath to easily add more cases
// to the switch block with just the hash algorithm name.
#define TGDFileChecksumCreateWithPath_CaseChecksumAlgorithmBranch( \
hashAlgorithmName \
) \
\
case TGDChecksumAlgorithm##hashAlgorithmName: \
do { \
TGDHashComputationContextDeclare(hashComputationContext, \
hashAlgorithmName); \
return _TGDFileHashCreateWithPath(filePath, \
chunkSizeForReadingData, \
&hashComputationContext); \
} while(false)
//---------------------------------------------------------
// Functions definitions
//---------------------------------------------------------
#pragma mark -
#pragma mark Functions definitions
CFStringRef TGDFileHashCreateWithPath(CFStringRef filePath,
size_t chunkSizeForReadingData,
TGDHashAlgorithm hashAlgorithm) {
switch (hashAlgorithm) {
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(MD2);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(MD4);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(MD5);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(SHA1);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(SHA224);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(SHA256);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(SHA384);
TGDFileHashCreateWithPath_CaseHashAlgorithmBranch(SHA512);
TGDFileChecksumCreateWithPath_CaseChecksumAlgorithmBranch(CRC32);
default:
break;
}
return NULL;
}
static CFStringRef _TGDFileHashCreateWithPath(CFStringRef filePath,
size_t chunkSizeForReadingData,
TGDHashComputationContext *context) {
// Declare needed variables and buffers
CFStringRef result = NULL;
CFReadStreamRef readStream = NULL;
unsigned char digest[context->digestLength];
char hash[2 * context->digestLength + 1];
// Get the file URL
CFURLRef fileURL =
CFURLCreateWithFileSystemPath(kCFAllocatorDefault,
(CFStringRef)filePath,
kCFURLPOSIXPathStyle,
(Boolean)false);
if (!fileURL) goto done;
// Create and open the read stream
readStream = CFReadStreamCreateWithFile(kCFAllocatorDefault,
(CFURLRef)fileURL);
if (!readStream) goto done;
bool didSucceed = (bool)CFReadStreamOpen(readStream);
if (!didSucceed) goto done;
// Initialize the hash object
(*context->initFunction)(context->hashObjectPointer);
// Make sure chunkSizeForReadingData is valid
if (!chunkSizeForReadingData) {
chunkSizeForReadingData = TGDFileHashDefaultChunkSizeForReadingData;
}
// Feed the data to the hash object
bool hasMoreData = true;
while (hasMoreData) {
uint8_t buffer[chunkSizeForReadingData];
CFIndex readBytesCount = CFReadStreamRead(readStream,
(UInt8 *)buffer,
(CFIndex)sizeof(buffer));
if (readBytesCount == -1) break;
if (readBytesCount == 0) {
hasMoreData = false;
continue;
}
(*context->updateFunction)(context->hashObjectPointer,
(const void *)buffer,
(CC_LONG)readBytesCount);
}
// Check if the read operation succeeded
didSucceed = !hasMoreData;
// Compute the hash digest
(*context->finalFunction)(digest, context->hashObjectPointer);
// Abort if the read operation failed
if (!didSucceed) goto done;
// Compute the string result
for (size_t i = 0; i < context->digestLength; ++i) {
snprintf(hash + (2 * i), 3, "%02x", (int)(digest[i]));
}
result = CFStringCreateWithCString(kCFAllocatorDefault,
(const char *)hash,
kCFStringEncodingUTF8);
done:
if (readStream) {
CFReadStreamClose(readStream);
CFRelease(readStream);
}
if (fileURL) {
CFRelease(fileURL);
}
return result;
}
static CC_LONG crc32_tbl[256] =
{
0x00000000L, 0x77073096L, 0xEE0E612CL, 0x990951BAL, 0x076DC419L,
0x706AF48FL, 0xE963A535L, 0x9E6495A3L, 0x0EDB8832L, 0x79DCB8A4L,
0xE0D5E91EL, 0x97D2D988L, 0x09B64C2BL, 0x7EB17CBDL, 0xE7B82D07L,
0x90BF1D91L, 0x1DB71064L, 0x6AB020F2L, 0xF3B97148L, 0x84BE41DEL,
0x1ADAD47DL, 0x6DDDE4EBL, 0xF4D4B551L, 0x83D385C7L, 0x136C9856L,
0x646BA8C0L, 0xFD62F97AL, 0x8A65C9ECL, 0x14015C4FL, 0x63066CD9L,
0xFA0F3D63L, 0x8D080DF5L, 0x3B6E20C8L, 0x4C69105EL, 0xD56041E4L,
0xA2677172L, 0x3C03E4D1L, 0x4B04D447L, 0xD20D85FDL, 0xA50AB56BL,
0x35B5A8FAL, 0x42B2986CL, 0xDBBBC9D6L, 0xACBCF940L, 0x32D86CE3L,
0x45DF5C75L, 0xDCD60DCFL, 0xABD13D59L, 0x26D930ACL, 0x51DE003AL,
0xC8D75180L, 0xBFD06116L, 0x21B4F4B5L, 0x56B3C423L, 0xCFBA9599L,
0xB8BDA50FL, 0x2802B89EL, 0x5F058808L, 0xC60CD9B2L, 0xB10BE924L,
0x2F6F7C87L, 0x58684C11L, 0xC1611DABL, 0xB6662D3DL, 0x76DC4190L,
0x01DB7106L, 0x98D220BCL, 0xEFD5102AL, 0x71B18589L, 0x06B6B51FL,
0x9FBFE4A5L, 0xE8B8D433L, 0x7807C9A2L, 0x0F00F934L, 0x9609A88EL,
0xE10E9818L, 0x7F6A0DBBL, 0x086D3D2DL, 0x91646C97L, 0xE6635C01L,
0x6B6B51F4L, 0x1C6C6162L, 0x856530D8L, 0xF262004EL, 0x6C0695EDL,
0x1B01A57BL, 0x8208F4C1L, 0xF50FC457L, 0x65B0D9C6L, 0x12B7E950L,
0x8BBEB8EAL, 0xFCB9887CL, 0x62DD1DDFL, 0x15DA2D49L, 0x8CD37CF3L,
0xFBD44C65L, 0x4DB26158L, 0x3AB551CEL, 0xA3BC0074L, 0xD4BB30E2L,
0x4ADFA541L, 0x3DD895D7L, 0xA4D1C46DL, 0xD3D6F4FBL, 0x4369E96AL,
0x346ED9FCL, 0xAD678846L, 0xDA60B8D0L, 0x44042D73L, 0x33031DE5L,
0xAA0A4C5FL, 0xDD0D7CC9L, 0x5005713CL, 0x270241AAL, 0xBE0B1010L,
0xC90C2086L, 0x5768B525L, 0x206F85B3L, 0xB966D409L, 0xCE61E49FL,
0x5EDEF90EL, 0x29D9C998L, 0xB0D09822L, 0xC7D7A8B4L, 0x59B33D17L,
0x2EB40D81L, 0xB7BD5C3BL, 0xC0BA6CADL, 0xEDB88320L, 0x9ABFB3B6L,
0x03B6E20CL, 0x74B1D29AL, 0xEAD54739L, 0x9DD277AFL, 0x04DB2615L,
0x73DC1683L, 0xE3630B12L, 0x94643B84L, 0x0D6D6A3EL, 0x7A6A5AA8L,
0xE40ECF0BL, 0x9309FF9DL, 0x0A00AE27L, 0x7D079EB1L, 0xF00F9344L,
0x8708A3D2L, 0x1E01F268L, 0x6906C2FEL, 0xF762575DL, 0x806567CBL,
0x196C3671L, 0x6E6B06E7L, 0xFED41B76L, 0x89D32BE0L, 0x10DA7A5AL,
0x67DD4ACCL, 0xF9B9DF6FL, 0x8EBEEFF9L, 0x17B7BE43L, 0x60B08ED5L,
0xD6D6A3E8L, 0xA1D1937EL, 0x38D8C2C4L, 0x4FDFF252L, 0xD1BB67F1L,
0xA6BC5767L, 0x3FB506DDL, 0x48B2364BL, 0xD80D2BDAL, 0xAF0A1B4CL,
0x36034AF6L, 0x41047A60L, 0xDF60EFC3L, 0xA867DF55L, 0x316E8EEFL,
0x4669BE79L, 0xCB61B38CL, 0xBC66831AL, 0x256FD2A0L, 0x5268E236L,
0xCC0C7795L, 0xBB0B4703L, 0x220216B9L, 0x5505262FL, 0xC5BA3BBEL,
0xB2BD0B28L, 0x2BB45A92L, 0x5CB36A04L, 0xC2D7FFA7L, 0xB5D0CF31L,
0x2CD99E8BL, 0x5BDEAE1DL, 0x9B64C2B0L, 0xEC63F226L, 0x756AA39CL,
0x026D930AL, 0x9C0906A9L, 0xEB0E363FL, 0x72076785L, 0x05005713L,
0x95BF4A82L, 0xE2B87A14L, 0x7BB12BAEL, 0x0CB61B38L, 0x92D28E9BL,
0xE5D5BE0DL, 0x7CDCEFB7L, 0x0BDBDF21L, 0x86D3D2D4L, 0xF1D4E242L,
0x68DDB3F8L, 0x1FDA836EL, 0x81BE16CDL, 0xF6B9265BL, 0x6FB077E1L,
0x18B74777L, 0x88085AE6L, 0xFF0F6A70L, 0x66063BCAL, 0x11010B5CL,
0x8F659EFFL, 0xF862AE69L, 0x616BFFD3L, 0x166CCF45L, 0xA00AE278L,
0xD70DD2EEL, 0x4E048354L, 0x3903B3C2L, 0xA7672661L, 0xD06016F7L,
0x4969474DL, 0x3E6E77DBL, 0xAED16A4AL, 0xD9D65ADCL, 0x40DF0B66L,
0x37D83BF0L, 0xA9BCAE53L, 0xDEBB9EC5L, 0x47B2CF7FL, 0x30B5FFE9L,
0xBDBDF21CL, 0xCABAC28AL, 0x53B39330L, 0x24B4A3A6L, 0xBAD03605L,
0xCDD70693L, 0x54DE5729L, 0x23D967BFL, 0xB3667A2EL, 0xC4614AB8L,
0x5D681B02L, 0x2A6F2B94L, 0xB40BBE37L, 0xC30C8EA1L, 0x5A05DF1BL,
0x2D02EF8DL
};
int CC_CRC32_Init(CC_CRC32_CTX *c) {
c->crc = 0xFFFFFFFFL;
return 0;
}
int CC_CRC32_Update(CC_CRC32_CTX *c, const uint8_t *data, CC_LONG len) {
CC_LONG crc = c->crc;
for(CC_LONG i=0; i<len;i++) {
crc = (crc>>8) ^ crc32_tbl[(crc&0xFF) ^ *data++];
}
c->crc = crc;
return 0;
}
int CC_CRC32_Final(unsigned char *md, CC_CRC32_CTX *c) {
CC_LONG crc = c->crc;
crc = crc ^ 0xFFFFFFFFL;
md[0] = (crc & 0xff000000UL) >> 24;
md[1] = (crc & 0x00ff0000UL) >> 16;
md[2] = (crc & 0x0000ff00UL) >> 8;
md[3] = (crc & 0x000000ffUL) ;
return 0;
}
Raw
TGDFileHash.h
/*
* TGDFileHash.h
* TagAdA: Tagging Advanced Application
*
* Copyright © 2008-2010 The TagAdA Team. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
#ifndef TGDFILEHASH_H
#define TGDFILEHASH_H
//---------------------------------------------------------
// Includes
//---------------------------------------------------------
// CoreFoundation
#include <CoreFoundation/CoreFoundation.h>
//---------------------------------------------------------
// Other declarations
//---------------------------------------------------------
#pragma mark -
#pragma mark Constants and types definitions
// In bytes
#define TGDFileHashDefaultChunkSizeForReadingData 4096
// TGDHashAlgorithm
enum {
TGDHashAlgorithmMD2 = 0,
TGDHashAlgorithmMD4,
TGDHashAlgorithmMD5,
TGDHashAlgorithmSHA1,
TGDHashAlgorithmSHA224,
TGDHashAlgorithmSHA256,
TGDHashAlgorithmSHA384,
TGDHashAlgorithmSHA512,
TGDChecksumAlgorithmCRC32
};
typedef unsigned int TGDHashAlgorithm;
//---------------------------------------------------------
// Function declaration
//---------------------------------------------------------
#pragma mark -
#pragma mark Function declaration
extern CFStringRef TGDFileHashCreateWithPath(CFStringRef filePath,
size_t chunkSizeForReadingData,
TGDHashAlgorithm hashAlgorithm);
#endif
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