介绍：
Objective-c实现MD5和SHA1算法相对还是比较简单的，可以直接调用系统的C/C++共享库来实现调用
MD5即Message Digest Algorithm 5（信息-摘要算法 5），用于确保信息传输完整一致。是计算机广泛使用的杂凑算法之一
SHA即Secure Hash Algorithm（安全散列算法) 是美国国家安全局 (NSA) 设计，美国国家标准与技术研究院 (NIST) 发布的一系列密码散列函数。
链接：http://m.111cn.net/art-53370.htm
使用方式如下:
MD5加密方式
-(NSString *) md5
{
const char *cStr = [self UTF8String];
unsigned char digest[CC_MD5_DIGEST_LENGTH];
CC_MD5( cStr, strlen(cStr), digest );
NSMutableString *output = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH * 2];
for(int i = 0; i < CC_MD5_DIGEST_LENGTH; i++)
[output appendFormat:@"%02x", digest[i]];
return output;
}
SHA1加密方式
- (NSString*) sha1
{
const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
NSData *data = [NSData dataWithBytes:cstr length:self.length];
uint8_t digest[CC_SHA1_DIGEST_LENGTH];
CC_SHA1(data.bytes, data.length, digest);
NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];
for(int i = 0; i < CC_SHA1_DIGEST_LENGTH; i++)
[output appendFormat:@"%02x", digest[i]];
return output;
}
当然也可以结合BASE64来使用,这里的BASE64编码使用 GTMBase64实现，需要导入
//结合base64的sha1加密
- (NSString *) sha1_base64
{
const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
NSData *data = [NSData dataWithBytes:cstr length:self.length];
uint8_t digest[CC_SHA1_DIGEST_LENGTH];
CC_SHA1(data.bytes, data.length, digest);
NSData * base64 = [[NSData alloc]initWithBytes:digest length:CC_SHA1_DIGEST_LENGTH];
base64 = [GTMBase64 encodeData:base64];
NSString * output = [[NSString alloc] initWithData:base64 encoding:NSUTF8StringEncoding];
return output;
}
//结合base64的md5加密
- (NSString *) md5_base64
{
const char *cStr = [self UTF8String];
unsigned char digest[CC_MD5_DIGEST_LENGTH];
CC_MD5( cStr, strlen(cStr), digest );
NSData * base64 = [[NSData alloc]initWithBytes:digest length:CC_MD5_DIGEST_LENGTH];
base64 = [GTMBase64 encodeData:base64];
NSString * output = [[NSString alloc] initWithData:base64 encoding:NSUTF8StringEncoding];
return output;
}
例子一：通过类扩展NSString，实现完整功能，全部代码
@interface NSString (encrypto)
- (NSString *) md5;
- (NSString *) sha1;
- (NSString *) sha1_base64;
- (NSString *) md5_base64;
- (NSString *) base64;
@end
@implementation NSString (encrypto)
- (NSString*) sha1
{
const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
NSData *data = [NSData dataWithBytes:cstr length:self.length];
uint8_t digest[CC_SHA1_DIGEST_LENGTH];
CC_SHA1(data.bytes, data.length, digest);
NSMutableString* output = [NSMutableString stringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];
for(int i = 0; i < CC_SHA1_DIGEST_LENGTH; i++)
[output appendFormat:@"%02x", digest[i]];
return output;
}
-(NSString *) md5
{
const char *cStr = [self UTF8String];
unsigned char digest[CC_MD5_DIGEST_LENGTH];
CC_MD5( cStr, strlen(cStr), digest );
NSMutableString *output = [NSMutableString stringWithCapacity:CC_MD5_DIGEST_LENGTH * 2];
for(int i = 0; i < CC_MD5_DIGEST_LENGTH; i++)
[output appendFormat:@"%02x", digest[i]];
return output;
}
- (NSString *) sha1_base64
{
const char *cstr = [self cStringUsingEncoding:NSUTF8StringEncoding];
NSData *data = [NSData dataWithBytes:cstr length:self.length];
uint8_t digest[CC_SHA1_DIGEST_LENGTH];
CC_SHA1(data.bytes, data.length, digest);
NSData * base64 = [[NSData alloc]initWithBytes:digest length:CC_SHA1_DIGEST_LENGTH];
base64 = [GTMBase64 encodeData:base64];
NSString * output = [[NSString alloc] initWithData:base64 encoding:NSUTF8StringEncoding];
return output;
}
- (NSString *) md5_base64
{
const char *cStr = [self UTF8String];
unsigned char digest[CC_MD5_DIGEST_LENGTH];
CC_MD5( cStr, strlen(cStr), digest );
NSData * base64 = [[NSData alloc]initWithBytes:digest length:CC_MD5_DIGEST_LENGTH];
base64 = [GTMBase64 encodeData:base64];
NSString * output = [[NSString alloc] initWithData:base64 encoding:NSUTF8StringEncoding];
return output;
}
- (NSString *) base64
{
NSData * data = [self dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];
data = [GTMBase64 encodeData:data];
NSString * output = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
return output;
}
@end
注意：
1.实现时候不要忘记导入CC相关的库的头文件
CommonCrypto/CommonDigest.h
2.在实现时还需要依赖这三个文件：GTMBase64.h GTMBase64.m GTMDefines.h
这三个文件的链接：
第一个：http://code.google.com/p/google-toolbox-for-mac/source/browse/trunk/Foundation/?r=87
第二个： gtmbase64.zip
例子二：通过类扩展NSString，实现完整功能，全部代码
.h文件
#import <Foundation/Foundation.h>
@interface NSString (Hash)
@property (readonly) NSString *md5String;
@property (readonly) NSString *sha1String;
@property (readonly) NSString *sha256String;
@property (readonly) NSString *sha512String;
- (NSString *)hmacSHA1StringWithKey:(NSString *)key;
- (NSString *)hmacSHA256StringWithKey:(NSString *)key;
- (NSString *)hmacSHA512StringWithKey:(NSString *)key;
@end
.m文件
//
// NSString+Hash.m
//
// Created by Tom Corwine on 5/30/12.
//
#import "NSString+hash.h"
#import <CommonCrypto/CommonDigest.h>
#import <CommonCrypto/CommonHMAC.h>
@implementation NSString (Hash)
- (NSString *)md5String
{
const char *string = self.UTF8String;
int length = (int)strlen(string);
unsigned char bytes[CC_MD5_DIGEST_LENGTH];
CC_MD5(string, length, bytes);
return [self stringFromBytes:bytes length:CC_MD5_DIGEST_LENGTH];
}
- (NSString *)sha1String
{
const char *string = self.UTF8String;
int length = (int)strlen(string);
unsigned char bytes[CC_SHA1_DIGEST_LENGTH];
CC_SHA1(string, length, bytes);
return [self stringFromBytes:bytes length:CC_SHA1_DIGEST_LENGTH];
}
- (NSString *)sha256String
{
const char *string = self.UTF8String;
int length = (int)strlen(string);
unsigned char bytes[CC_SHA256_DIGEST_LENGTH];
CC_SHA256(string, length, bytes);
return [self stringFromBytes:bytes length:CC_SHA256_DIGEST_LENGTH];
}
- (NSString *)sha512String
{
const char *string = self.UTF8String;
int length = (int)strlen(string);
unsigned char bytes[CC_SHA512_DIGEST_LENGTH];
CC_SHA512(string, length, bytes);
return [self stringFromBytes:bytes length:CC_SHA512_DIGEST_LENGTH];
}
- (NSString *)hmacSHA1StringWithKey:(NSString *)key
{
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
NSData *messageData = [self dataUsingEncoding:NSUTF8StringEncoding];
NSMutableData *mutableData = [NSMutableData dataWithLength:CC_SHA1_DIGEST_LENGTH];
CCHmac(kCCHmacAlgSHA1, keyData.bytes, keyData.length, messageData.bytes, messageData.length, mutableData.mutableBytes);
return [self stringFromBytes:(unsigned char *)mutableData.bytes length:mutableData.length];
}
- (NSString *)hmacSHA256StringWithKey:(NSString *)key
{
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
NSData *messageData = [self dataUsingEncoding:NSUTF8StringEncoding];
NSMutableData *mutableData = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];
CCHmac(kCCHmacAlgSHA256, keyData.bytes, keyData.length, messageData.bytes, messageData.length, mutableData.mutableBytes);
return [self stringFromBytes:(unsigned char *)mutableData.bytes length:mutableData.length];
}
- (NSString *)hmacSHA512StringWithKey:(NSString *)key
{
NSData *keyData = [key dataUsingEncoding:NSUTF8StringEncoding];
NSData *messageData = [self dataUsingEncoding:NSUTF8StringEncoding];
NSMutableData *mutableData = [NSMutableData dataWithLength:CC_SHA512_DIGEST_LENGTH];
CCHmac(kCCHmacAlgSHA512, keyData.bytes, keyData.length, messageData.bytes, messageData.length, mutableData.mutableBytes);
return [self stringFromBytes:(unsigned char *)mutableData.bytes length:mutableData.length];
}
#pragma mark - Helpers
- (NSString *)stringFromBytes:(unsigned char *)bytes length:(int)length
{
NSMutableString *mutableString = @"".mutableCopy;
for (int i = 0; i < length; i++)
[mutableString appendFormat:@"%02x", bytes[i]];
return [NSString stringWithString:mutableString];
}
@end
