我試圖使用DES
加密來加密密碼(不要問爲什麼DES,我知道它不太安全)。我在iOS中第一次這樣做,因此不得不依賴另一篇關於如何去做的文章。EXC_BAD_ACCESS CCCrypt上的代碼2
當我運行加密時,它返回null,與解密已加密的字符串(我使用在線工具進行加密)相同。當我放置一個斷點來看看發生了什麼,它停在CCCrypt
提到EXC_BAD_ACCESS (Code 2)
。
我試過使用不同的CCOptions,但它總是返回相同的東西。 任何提示發生了什麼問題? iv字符串是否必需?
我用下面的NSString類別進行加密或解密的字符串 -
#import "NSString+DES.h"
@implementation NSString(DES)
- (NSString*) encryptDES: (NSString *) key
{
const void *vplainText;
size_t plainTextBufferSize;
plainTextBufferSize = [self length];
vplainText = (const void *) [self UTF8String];
CCCryptorStatus ccStatus;
uint8_t *bufferPtr = NULL;
size_t bufferPtrSize = 0;
size_t *movedBytes;
bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);
bufferPtr = malloc(bufferPtrSize * sizeof(uint8_t));
memset((void *)bufferPtr, 0x0, bufferPtrSize);
// memset((void *) iv, 0x0, (size_t) sizeof(iv));
//NSString *initVec = @"init Vec";
const void *vkey = (const void *) [key UTF8String];
//const void *vinitVec = (const void *) [initVec UTF8String];
ccStatus = CCCrypt(kCCEncrypt,
kCCAlgorithmDES,
kCCOptionPKCS7Padding | kCCOptionECBMode,
vkey,
kCCKeySizeDES,
NULL,
vplainText,
plainTextBufferSize,
(void *)bufferPtr,
bufferPtrSize,
movedBytes);
NSString *result;
NSData *myData = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes];
result = [myData base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
return result;
}
- (NSString *) decryptDES: (NSString *) key
{
const void *vplainText;
size_t plainTextBufferSize;
plainTextBufferSize = [self length];
vplainText = (const void *) [self UTF8String];
CCCryptorStatus ccStatus;
uint8_t *bufferPtr = NULL;
size_t bufferPtrSize = 0;
size_t *movedBytes;
bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);
bufferPtr = malloc(bufferPtrSize * sizeof(uint8_t));
memset((void *)bufferPtr, 0x0, bufferPtrSize);
// memset((void *) iv, 0x0, (size_t) sizeof(iv));
//NSString *initVec = @"init Vec";
const void *vkey = (const void *) [key UTF8String];
//const void *vinitVec = (const void *) [initVec UTF8String];
ccStatus = CCCrypt(kCCDecrypt,
kCCAlgorithmDES,
kCCOptionPKCS7Padding | kCCOptionECBMode,
vkey, //"123456789", //key
kCCKeySizeDES,
NULL,// vinitVec, //"init Vec", //iv,
vplainText, //"Your Name", //plainText,
plainTextBufferSize,
(void *)bufferPtr,
bufferPtrSize,
movedBytes);
NSString *result;
NSData *myData = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes];
result = [myData base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
return result;
}
@end
更新:
我已經檢查了幾個地方,並改變了代碼一點點,加密工作,但沒有使用正確的值解密。
例如,當我使用YourName
string和12345
爲重點,我得到Fu2sK61e7l5rkXRhAKjPWA==
作爲加密密碼,但解密返回+54qWCYTB5LkdARDZjAow==
,而不是YourName
。
更新的代碼:
#import "NSString+DES.h"
@implementation NSString(DES)
- (NSString*) encryptDES: (NSString *) key
{
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
NSData *stringData = [self dataUsingEncoding:NSUTF8StringEncoding];
size_t numBytesEncrypted = 0;
size_t bufferSize = stringData.length + kCCBlockSizeDES;
void *buffer = malloc(bufferSize);
CCCryptorStatus result = CCCrypt(kCCEncrypt, kCCAlgorithmDES, kCCOptionPKCS7Padding,
keyData.bytes, kCCKeySizeDES,
NULL,
stringData.bytes, stringData.length,
buffer, bufferSize,
&numBytesEncrypted);
NSData *output = [NSData dataWithBytes:buffer length:numBytesEncrypted];
free(buffer);
if(result == kCCSuccess)
{
NSString *resultStr = [output base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
return resultStr;
} else {
NSLog(@"Failed DES encrypt...");
return nil;
}
}
- (NSString *) decryptDES: (NSString *) key
{
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
NSData *stringData = [[NSData alloc] initWithBase64EncodedString:self options:0];
size_t numBytesEncrypted = 0;
size_t bufferSize = stringData.length + kCCBlockSizeDES;
void *buffer = malloc(bufferSize);
CCCryptorStatus result = CCCrypt(kCCDecrypt, kCCAlgorithmDES, kCCOptionPKCS7Padding,
keyData.bytes, kCCKeySizeDES,
NULL,
stringData.bytes, stringData.length,
buffer, bufferSize,
&numBytesEncrypted);
NSData *output = [NSData dataWithBytes:buffer length:numBytesEncrypted];
free(buffer);
if(result == kCCSuccess)
{
NSString *resultStr = [output base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
return resultStr;
} else {
NSLog(@"Failed DES decrypt...");
return nil;
}
}
@end
@Bhavin'ccStatus = CCCrypt(...);'是這裏的罪魁禍首。 – noob
ok ..你檢查這個鏈接... http://stackoverflow.com/questions/11717193/exc-bad-access-code-2 –
ECB模式不使用iv。 – zaph