iOS之加密的三种方法

  1 //需要导入   #import <CommonCrypto/CommonCryptor.h> 
  2 
  3 ==============MD5加密============ 
  4 
  5 NSString *str = @"加密的内容"; 
  6 
  7         //转换成C语言的字符串 
  8 
  9         const char *cStr=[str UTF8String]; 
 10 
 11         //MD5加密的结果是128位，需要开辟一个16字节的空间 
 12 
 13         unsigned char result[16]; 
 14 
 15         //调用加密函数 
 16 
 17         CC_MD5(cStr, (unsigned int)strlen(cStr), result); 
 18 
 19         //通过上面这个方法获取的MD5是一个16个字符的数组，需要转换成32位的MD5值 
 20 
 21         NSMutableString *string = [NSMutableString stringWithCapacity:10]; 
 22 
 23         for (int i=; i<16; i++) { 
 24 
 25             [string appendString:[NSString stringWithFormat:@"%02x",result[i]]]; 
 26 
 27         } 
 28 
 29         NSLog(@"MD5加密:%@",string); 
 30 
 31  
 32 
 33 ===============base64加密解密============= 
 34 
 35 //ios7 以后提供了base64的转码方式 
 36 
 37         //加密 
 38 
 39         NSString *pass=@"加密的内容"; 
 40 
 41         NSData *passData=[pass dataUsingEncoding:NSUTF8StringEncoding]; 
 42 
 43         NSString *result = [passData base64EncodedStringWithOptions:NSDataBase64EncodingEndLineWithLineFeed]; 
 44 
 45         NSLog(@"base64加密:%@",result); 
 46 
 47          
 48 
 49         //解密 
 50 
 51         NSData *decodeData = [[NSData alloc]initWithBase64EncodedString:result options:]; 
 52 
 53         NSString *decodeStr = [[NSString alloc]initWithData:decodeData encoding:NSUTF8StringEncoding]; 
 54 
 55         NSLog(@"base64解密:%@",decodeStr); 
 56 
 57  
 58 
 59 ================AES加密解密=============== 
 60 
 61 //新建一个NSData类,写入一下两个方法 
 62 
 63 //加密方法 
 64 
 65 - (NSData*)AES256EncryptWithKey:(NSString*)key { 
 66 
 67      
 68 
 69     char keyPtr[kCCKeySizeAES256 + 1]; // room for terminator (unused) 
 70 
 71     bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding) 
 72 
 73      
 74 
 75     [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; 
 76 
 77      
 78 
 79     NSUInteger dataLength = [self length]; 
 80 
 81      
 82 
 83     size_t bufferSize           = dataLength + kCCBlockSizeAES128; 
 84 
 85     void* buffer                = malloc(bufferSize); 
 86 
 87      
 88 
 89     size_t numBytesEncrypted    = ; 
 90 
 91     CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, 
 92 
 93                                           keyPtr, kCCKeySizeAES256, 
 94 
 95                                           NULL /* initialization vector (optional) */, 
 96 
 97                                           [self bytes], dataLength, /* input */ 
 98 
 99                                           buffer, bufferSize, /* output */ 
100 
101                                           &numBytesEncrypted); 
102 
103      
104 
105     if (cryptStatus == kCCSuccess) { 
106 
107         return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted]; 
108 
109     } 
110 
111      
112 
113     free(buffer); 
114 
115     return nil; 
116 
117 } 
118 
119 //解密方法 
120 
121 - (NSData*)AES256DecryptWithKey:(NSString*)key { 
122 
123      
124 
125     char keyPtr[kCCKeySizeAES256 + 1]; // room for terminator (unused) 
126 
127     bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding) 
128 
129      
130 
131     // fetch key data 
132 
133     [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; 
134 
135      
136 
137     NSUInteger dataLength = [self length]; 
138 
139      
140 
141     size_t bufferSize           = dataLength + kCCBlockSizeAES128; 
142 
143     void* buffer                = malloc(bufferSize); 
144 
145      
146 
147     size_t numBytesDecrypted    = ; 
148 
149     CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, 
150 
151                                           keyPtr, kCCKeySizeAES256, 
152 
153                                           NULL /* initialization vector (optional) */, 
154 
155                                           [self bytes], dataLength, /* input */ 
156 
157                                           buffer, bufferSize, /* output */ 
158 
159                                           &numBytesDecrypted); 
160 
161      
162 
163     if (cryptStatus == kCCSuccess) { 
164 
165         return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted]; 
166 
167     } 
168 
169      
170 
171     free(buffer); //free the buffer; 
172 
173  
174 
175 在另外的类里面调用上面NSData里面的方法 
176 
177 //==========AES加密解密============= 
178 
179         NSString *key = @"mykey";//钥匙 
180 
181         NSString *secret = @"加密内容";//准备加密的内容 
182 
183         NSData *plain = [secret dataUsingEncoding:NSUTF8StringEncoding]; 
184 
185         NSData *ciper = [plain AES256EncryptWithKey:key]; 
186 
187         NSLog(@"AES加密%@",ciper); 
188 
189         //解密 
190 
191         plain = [ciper AES256DecryptWithKey:key]; 
192 
193          NSLog(@"AES解密:%@",[[NSString alloc]initWithData:plain encoding:NSUTF8StringEncoding]);