有个项目用过AES128 （CBC）的加密，当时搜索了很久的资料，基本不能使用。这里我自己写了一个可以用的 代码如下：
（PS：这个方法写的还有些瑕疵 不过已经足够正常使用了，有机会的话 会写的好看一点。。。转发要标注出处哦）
这是.h
1 // 2 // AES128CBC_No_Padding_Unit.h 3 // 4 // 5 // Created by apple on 14-5-13. 6 // Copyright (c) 2014年 akforsure. All rights reserved. 7 // 8 9 #import <Foundation/Foundation.h> 10 11 @interface AES128CBC_No_Padding_Unit : NSObject 12 /** 13 * AES128加密 14 * 15 * @param plainText 原文 16 * 17 * @return 加密好的字符串 18 */ 19 + (NSString *)AES128Encrypt:(NSString *)plainText; 20 /** 21 * AES128解密 22 * 23 * @param encryptText 密文 24 * 25 * @return 明文 26 */ 27 + (NSString *)AES128Decrypt:(NSString *)encryptText; 28 @end
这是.m
1 // 2 // AES128CBC_No_Padding_Unit.m 3 // 4 // 5 // Created by apple on 14-5-13. 6 // Copyright (c) 2014年 akforsure. All rights reserved. 7 // 8 9 #import "AES128CBC_No_Padding_Unit.h" 10 #import <CommonCrypto/CommonCryptor.h> 11 #import "GTMBase64.h" 12 @implementation AES128CBC_No_Padding_Unit 13 + (NSString *)AES128Encrypt:(NSString *)plainText 14 { 15 char keyPtr[kCCKeySizeAES128+1]; 16 memset(keyPtr, 0, sizeof(keyPtr)); 17 [AESKEY getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; 18 19 char ivPtr[kCCBlockSizeAES128+1]; 20 memset(ivPtr, 0, sizeof(ivPtr)); 21 [AESIV getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding]; 22 23 NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding]; 24 NSUInteger dataLength = [data length]; 25 26 int diff = kCCKeySizeAES128 - (dataLength % kCCKeySizeAES128); 27 int newSize = 0; 28 29 if(diff > 0) 30 { 31 newSize = dataLength + diff; 32 } 33 34 char dataPtr[newSize]; 35 memcpy(dataPtr, [data bytes], [data length]); 36 for(int i = 0; i < diff; i++) 37 { 38 dataPtr[i + dataLength] = 0x00; 39 } 40 41 size_t bufferSize = newSize + kCCBlockSizeAES128; 42 void *buffer = malloc(bufferSize); 43 memset(buffer, 0, bufferSize); 44 45 size_t numBytesCrypted = 0; 46 47 CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, 48 kCCAlgorithmAES128, 49 0x0000, //这里用的 NoPadding的填充方式 50 //除此以外还有 kCCOptionPKCS7Padding 和 kCCOptionECBMode 51 keyPtr, 52 kCCKeySizeAES128, 53 ivPtr, 54 dataPtr, 55 sizeof(dataPtr), 56 buffer, 57 bufferSize, 58 &numBytesCrypted); 59 60 if (cryptStatus == kCCSuccess) { 61 NSData *resultData = [NSData dataWithBytesNoCopy:buffer length:numBytesCrypted]; 62 return [GTMBase64 stringByEncodingData:resultData]; 63 } 64 free(buffer); 65 return nil; 66 } 67 68 + (NSString *)AES128Decrypt:(NSString *)encryptText 69 { 70 char keyPtr[kCCKeySizeAES128 + 1]; 71 memset(keyPtr, 0, sizeof(keyPtr)); 72 [AESKEY getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; 73 74 char ivPtr[kCCBlockSizeAES128 + 1]; 75 memset(ivPtr, 0, sizeof(ivPtr)); 76 [AESIV getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding]; 77 78 NSData *data = [GTMBase64 decodeData:[encryptText dataUsingEncoding:NSUTF8StringEncoding]]; 79 NSUInteger dataLength = [data length]; 80 size_t bufferSize = dataLength + kCCBlockSizeAES128; 81 void *buffer = malloc(bufferSize); 82 83 size_t numBytesCrypted = 0; 84 CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, 85 kCCAlgorithmAES128, 86 0x0000, 87 keyPtr, 88 kCCBlockSizeAES128, 89 ivPtr, 90 [data bytes], 91 dataLength, 92 buffer, 93 bufferSize, 94 &numBytesCrypted); 95 if (cryptStatus == kCCSuccess) { 96 NSData *resultData = [NSData dataWithBytesNoCopy:buffer length:numBytesCrypted]; 97 return [[[NSString alloc] initWithData:resultData encoding:NSUTF8StringEncoding] autorelease]; 98 } 99 free(buffer); 100 return nil; 101 } 102 103 @end