下面我将用代码来阐述其使用方法。 首先我们创建一个NSData的类扩展,命名为AES,创建完如果对的话应该是这样的NSData+AES然后导入如下头文件
#import <CommonCrypto/CommonDigest.h>#import <CommonCrypto/CommonCryptor.h>
再增加加解密的方法,方便外部文件的调用,写完.h文件如下
#import <Foundation/Foundation.h> #import <CommonCrypto/CommonDigest.h> #import <CommonCrypto/CommonCryptor.h> @interface NSData (AES)//加密 - (NSData *) AES256_Encrypt:(NSString *)key;//解密 - (NSData *) AES256_Decrypt:(NSString *)key;//追加64编码 - (NSString *)newStringInBase64FromData;//同上64编码 + (NSString*)base64encode:(NSString*)str;@end
.m文件中依次实现这几个方法,具体如下
#import "NSData+AES.h" static char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";@implementation NSData (AES)//加密 - (NSData *) AES256_Encrypt:(NSString *)key{
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;
}//解密 - (NSData *) AES256_Decrypt:(NSString *)key{
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;
}//追加64编码 - (NSString *)newStringInBase64FromData { NSMutableString *dest = [[NSMutableString alloc] initWithString:@""]; unsigned char * working = (unsigned char *)[self bytes]; int srcLen = (int)[self length]; for (int i=0; i<srcLen; i += 3) { for (int nib=0; nib<4; nib++) { int byt = (nib == 0)?0:nib-1; int ix = (nib+1)*2; if (i+byt >= srcLen) break; unsigned char curr = ((working[i+byt] << (8-ix)) & 0x3F); if (i+nib < srcLen) curr |= ((working[i+nib] >> ix) & 0x3F);
[dest appendFormat:@"%c", base64[curr]];
}
} return dest;
}
+ (NSString*)base64encode:(NSString*)str
{ if ([str length] == 0) return @""; const char *source = [str UTF8String]; int strlength = (int)strlen(source); char *characters = malloc(((strlength + 2) / 3) * 4); if (characters == NULL) return nil; NSUInteger length = 0; NSUInteger i = 0; while (i < strlength) { char buffer[3] = {0,0,0}; short bufferLength = 0; while (bufferLength < 3 && i < strlength)
buffer[bufferLength++] = source[i++];
characters[length++] = base64[(buffer[0] & 0xFC) >> 2];
characters[length++] = base64[((buffer[0] & 0x03) << 4) | ((buffer[1] & 0xF0) >> 4)]; if (bufferLength > 1)
characters[length++] = base64[((buffer[1] & 0x0F) << 2) | ((buffer[2] & 0xC0) >> 6)]; else characters[length++] = '='; if (bufferLength > 2)
characters[length++] = base64[buffer[2] & 0x3F]; else characters[length++] = '=';
} NSString *g = [[NSString alloc] initWithBytesNoCopy:characters length:length encoding:NSASCIIStringEncoding freeWhenDone:YES]; return g;
}@end
AES+Base64的加密方式到此已经结束了,下面讲一下单纯的AES字符串加密的。
和上面的基本上差不多,写一个NSString的类扩展,命名为AES,创建完如果对的话应该是这样的NSString+AES导入如下头文件
#import "NSData+AES.h"
同样的把加解密的方法写在.h文件中,写完如下
#import <Foundation/Foundation.h> #import "NSData+AES.h" @interface NSString (AES)//加密 - (NSString *) AES256_Encrypt:(NSString *)key;//解密 - (NSString *) AES256_Decrypt:(NSString *)key;@end
.m实现方法
//加密- (NSString *) AES256_Encrypt:(NSString *)key{ const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding]; NSData *data = [NSData dataWithBytes:cstr length:self.length]; //对数据进行加密
NSData *result = [data AES256_Encrypt:key]; //转换为2进制字符串
if (result && result.length > 0) {
Byte *datas = (Byte*)[result bytes]; NSMutableString *output = [NSMutableString stringWithCapacity:result.length * 2]; for(int i = 0; i < result.length; i++){
[output appendFormat:@"%02x", datas[i]];
} return output;
} return nil;
}//解密- (NSString *) AES256_Decrypt:(NSString *)key{ //转换为2进制Data
NSMutableData *data = [NSMutableData dataWithCapacity:self.length / 2]; unsigned char whole_byte; char byte_chars[3] = {'\0','\0','\0'}; int i; for (i=0; i < [self length] / 2; i++) {
byte_chars[0] = [self characterAtIndex:i*2];
byte_chars[1] = [self characterAtIndex:i*2+1];
whole_byte = strtol(byte_chars, NULL, 16);
[data appendBytes:&whole_byte length:1];
} //对数据进行解密
NSData* result = [data AES256_Decrypt:key]; if (result && result.length > 0) { return [[NSString alloc] initWithData:result encoding:NSUTF8StringEncoding];
} return nil;
}
到此我们加密的文件基本上都已经OK了,下面我们来简单的的使用一下,具体如下:
#import "ViewController.h" #import "NSString+AES.h" @interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {
[super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib.
//字符串加密 NSString *key = @"12345678";//Key是和后台约定的key哦,不然无法解密....
NSString *secret = @"aes Bison base64"; NSLog(@"字符串加密---%@",[secret AES256_Encrypt:key]); //字符串解密 NSLog(@"字符串解密---%@",[[secret AES256_Encrypt:key] AES256_Decrypt:key]);
//NSData加密+base64
NSData *plain = [secret dataUsingEncoding:NSUTF8StringEncoding]; NSData *cipher = [plain AES256_Encrypt:key]; NSLog(@"NSData加密+base64++++%@",[cipher newStringInBase64FromData]); //解密
plain = [cipher AES256_Decrypt:key]; NSLog(@"NSData解密+base64++++%@", [[NSString alloc] initWithData:plain encoding:NSUTF8StringEncoding]);
}@end
运行得到打印的结果如下:
2016-03-30 17:31:55.686 AES_256[14242:198853] 字符串加密---07815ca46d20acc3ba4e43d6930c7537496e851a36dbeac34fa30c5796089b02
2016-03-30 17:31:55.687 AES_256[14242:198853] 字符串解密---aes Bison base64
2016-03-30 17:31:55.687 AES_256[14242:198853] NSData加密+base64++++B4FcpG0grMO6TkPWkwx1N0luhRo22+rDT6MMV5YImwI
2016-03-30 17:31:55.687 AES_256[14242:198853] NSData解密+base64++++aes Bison base64
##值得注意的是Key是和后台约定的key哦,不然无法解密….
demo下载地址 https://github.com/AllLuckly/LBAES/tree/master
转载于:https://my.oschina.net/u/2562364/blog/669205