标签：.com range nta tables 文件 www malloc ase res
基于64个可打印的字符来表示二进制数据的方法。
Base64编码：
- (NSString *)encode:(NSString *)string { //先将string转换成data NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding]; NSData *base64Data = [data base64EncodedDataWithOptions:0]; NSString *baseString = [[NSString alloc]initWithData:base64Data encoding:NSUTF8StringEncoding]; return baseString; }
Base64解码：
- (NSString *)dencode:(NSString *)base64String { //NSData *base64data = [string dataUsingEncoding:NSUTF8StringEncoding]; NSData *data = [[NSData alloc]initWithBase64EncodedString:base64String options:NSDataBase64DecodingIgnoreUnknownCharacters]; NSString *string = [[NSString alloc]initWithData:data encoding:NSUTF8StringEncoding]; return string; }
MD5加密是从一段字符串中通过相应特征生成一段32位的数字字母混合码。对输入信息生成唯一的固定的128位散列值（32个字符），即128个0和1的二进制位，而在实际应用开发中，通常是以16进制输出的，所以正好就是32位的16进制。MD5主要特点是 不可逆，相同数据的MD5值肯定一样。
（1）一定要和后台开发人员约定好，MD5加密的位数是16位还是32位(大多数都是32位的)，16位的可以通过32位的转换得到。
（2）MD5加密区分 大小写，使用时要和后台约定好。
MD5解密网站:http://www.cmd5.com/
加密方法：
#import@interface MD5Encrypt : NSObject // MD5加密 /* *由于MD5加密是不可逆的,多用来进行验证 */ // 32位小写 +(NSString *)MD5ForLower32Bate:(NSString *)str; // 32位大写 +(NSString *)MD5ForUpper32Bate:(NSString *)str; // 16为大写 +(NSString *)MD5ForUpper16Bate:(NSString *)str; // 16位小写 +(NSString *)MD5ForLower16Bate:(NSString *)str; @end
#import "MD5Encrypt.h" #import <CommonCrypto/CommonDigest.h> @implementation MD5Encrypt #pragma mark - 32位 小写 +(NSString *)MD5ForLower32Bate:(NSString *)str{ //要进行UTF8的转码 const char* input = [str UTF8String]; unsigned char result[CC_MD5_DIGEST_LENGTH]; CC_MD5(input, (CC_LONG)strlen(input), result); NSMutableString *digest = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH * 2]; for (NSInteger i = 0; i < CC_MD5_DIGEST_LENGTH; i++) { [digest appendFormat:@"%02x", result[i]]; } return digest; } #pragma mark - 32位 大写 +(NSString *)MD5ForUpper32Bate:(NSString *)str{ //要进行UTF8的转码 const char* input = [str UTF8String]; unsigned char result[CC_MD5_DIGEST_LENGTH]; CC_MD5(input, (CC_LONG)strlen(input), result); NSMutableString *digest = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH * 2]; for (NSInteger i = 0; i < CC_MD5_DIGEST_LENGTH; i++) { [digest appendFormat:@"%02X", result[i]]; } return digest; } #pragma mark - 16位 大写 +(NSString *)MD5ForUpper16Bate:(NSString *)str{ NSString *md5Str = [self MD5ForUpper32Bate:str]; NSString *string; for (int i=0; i<24; i++) { string=[md5Str substringWithRange:NSMakeRange(8, 16)]; } return string; } #pragma mark - 16位 小写 +(NSString *)MD5ForLower16Bate:(NSString *)str{ NSString *md5Str = [self MD5ForLower32Bate:str]; NSString *string; for (int i=0; i<24; i++) { string=[md5Str substringWithRange:NSMakeRange(8, 16)]; } return string; } @end
AES:高级加密标准(Advanced Encryption Standard)
加密步骤: 字符串经过AES加密得到NSData类型数据，然后在对加密后的NSData数据进行Base64转码，得出最终的字符串
解密步骤: 对要解密的字符串进行Base64解码得到NSData类型数据，然后对NSData数据经过AES解密，得出原字符串
//创建一个基于NSObject的AESUtility类 #import <Foundation/Foundation.h> @interface AESUtility : NSObject + (NSString *)EncryptString:(NSString *)sourceStr; + (NSString *)DecryptString:(NSString *)secretStr; @end
#import "AESUtility.h" #import <CommonCrypto/CommonDigest.h> #import <CommonCrypto/CommonCryptor.h> //加密与解密的秘钥，保持与后台的秘钥相同 static NSString *key = @"12345678"; @implementation AESUtility + (NSString *)EncryptString:(NSString *)sourceStr { char keyPtr[kCCKeySizeAES256 + 1]; bzero(keyPtr, sizeof(keyPtr)); [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; NSData *sourceData = [sourceStr dataUsingEncoding:NSUTF8StringEncoding]; NSUInteger dataLength = [sourceData length]; size_t buffersize = dataLength + kCCBlockSizeAES128; void *buffer = malloc(buffersize); size_t numBytesEncrypted = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding | kCCOptionECBMode, keyPtr, kCCBlockSizeAES128, NULL, [sourceData bytes], dataLength, buffer, buffersize, &numBytesEncrypted); if (cryptStatus == kCCSuccess) { NSData *encryptData = [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted]; //对加密后的二进制数据进行base64转码 return [encryptData base64EncodedStringWithOptions:NSDataBase64EncodingEndLineWithLineFeed]; } else { free(buffer); return nil; } } + (NSString *)DecryptString:(NSString *)secretStr { //先对加密的字符串进行base64解码 NSData *decodeData = [[NSData alloc] initWithBase64EncodedString:secretStr options:NSDataBase64DecodingIgnoreUnknownCharacters]; char keyPtr[kCCKeySizeAES256 + 1]; bzero(keyPtr, sizeof(keyPtr)); [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; NSUInteger dataLength = [decodeData length]; size_t bufferSize = dataLength + kCCBlockSizeAES128; void *buffer = malloc(bufferSize); size_t numBytesDecrypted = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding | kCCOptionECBMode, keyPtr, kCCBlockSizeAES128, NULL, [decodeData bytes], dataLength, buffer, bufferSize, &numBytesDecrypted); if (cryptStatus == kCCSuccess) { NSData *data = [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted]; NSString *result = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; return result; } else { free(buffer); return nil; } } @end
注意点：
1. 加密与解密的秘钥key，需要与后台协商共同定义，保持与后台的秘钥相同，也可以通过接口从后台获得；
2. 导入头文件：#import <CommonCrypto/CommonDigest.h>和#import <CommonCrypto/CommonCryptor.h>
标签：.com range nta tables 文件 www malloc ase res
原文地址：https://www.cnblogs.com/Blueleaf-tech/p/9807826.html
