iOS系統方法進行AES對稱式加密

廢話不多說，直接上代碼：

標頭檔：

#import @class NSString;@interface NSData (Encryption)- (NSData *)AES256ParmEncryptWithKey:(NSString *)key;   //加密- (NSData *)AES256ParmDecryptWithKey:(NSString *)key;   //解密@end

.m實現檔案：

#import "Encryption.h"#import @implementation NSData (Encryption)- (NSData *)AES256ParmEncryptWithKey:(NSString *)key   //加密{    char keyPtr[kCCKeySizeAES256+1];    bzero(keyPtr, sizeof(keyPtr));    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];    NSUInteger dataLength = [self length];    size_t bufferSize = dataLength + kCCBlockSizeAES128;    void *buffer = malloc(bufferSize);    size_t numBytesEncrypted = 0;    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128,                                          kCCOptionPKCS7Padding | kCCOptionECBMode,                                          keyPtr, kCCBlockSizeAES128,                                          NULL,                                          [self bytes], dataLength,                                          buffer, bufferSize,                                          &numBytesEncrypted);    if (cryptStatus == kCCSuccess) {        return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];    }    free(buffer);    return nil;}- (NSData *)AES256ParmDecryptWithKey:(NSString *)key   //解密{    char keyPtr[kCCKeySizeAES256+1];    bzero(keyPtr, sizeof(keyPtr));    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];    NSUInteger dataLength = [self length];    size_t bufferSize = dataLength + kCCBlockSizeAES128;    void *buffer = malloc(bufferSize);    size_t numBytesDecrypted = 0;    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128,                                          kCCOptionPKCS7Padding | kCCOptionECBMode,                                          keyPtr, kCCBlockSizeAES128,                                          NULL,                                          [self bytes], dataLength,                                          buffer, bufferSize,                                          &numBytesDecrypted);    if (cryptStatus == kCCSuccess) {        return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];    }    free(buffer);    return nil;}