iOS開發之Objective-c的MD5/SHA1加密算法的實作

原文位址：點選打開連結

Objective-c實作MD5和SHA1算法相對還是比較簡單的，可以直接調用系統的C/C++共享庫來實作調用

MD5即MessageDigest Algorithm 5（資訊-摘要算法 5），用于確定資訊傳輸完整一緻。是計算機廣泛使用的雜湊算法之一

SHA即SecureHash Algorithm（安全雜湊演算法) 是美國國家安全局(NSA) 設計，美國國家标準與技術研究院 (NIST) 釋出的一系列密碼散列函數。

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 = [NSMutableStringstringWithCapacity: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 = [selfcStringUsingEncoding:NSUTF8StringEncoding];

    NSData*data = [NSDatadataWithBytes:cstr length:self.length];

    uint8_t digest[CC_SHA1_DIGEST_LENGTH];

    CC_SHA1(data.bytes, data.length, digest);

    NSMutableString*output = [NSMutableStringstringWithCapacity:CC_SHA1_DIGEST_LENGTH * 2];

    for(int i = 0; i <CC_SHA1_DIGEST_LENGTH; i++)

        [output appendFormat:@"%02x",digest[i]];

    return output;

}

當然也可以結合BASE64來使用,這裡的BASE64編碼使用 GTMBase64實作，需要導入

- (NSString*) sha1_base64

{

    const char *cstr = [selfcStringUsingEncoding:NSUTF8StringEncoding];

    NSData*data = [NSDatadataWithBytes:cstr length:self.length];

    uint8_t digest[CC_SHA1_DIGEST_LENGTH];

    CC_SHA1(data.bytes, data.length, digest);

    NSData* base64 = [[NSDataalloc]initWithBytes:digest length:CC_SHA1_DIGEST_LENGTH];

    base64 = [GTMBase64 encodeData:base64];

    NSString* output = [[NSStringalloc] 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 = [[NSDataalloc]initWithBytes:digest length:CC_MD5_DIGEST_LENGTH];

    base64 = [GTMBase64 encodeData:base64];

    NSString* output = [[NSStringalloc] initWithData:base64 encoding:NSUTF8StringEncoding];

    return output;

}

通過拓展NSString，實作完整功能，全部代碼

@interface NSString(encrypto)

- (NSString*) md5;

- (NSString*) sha1;

- (NSString*) sha1_base64;

- (NSString*) md5_base64;

- (NSString*) base64;

@end

@implementation NSString(encrypto)

- (NSString*)sha1

{

    const char *cstr = [selfcStringUsingEncoding:NSUTF8StringEncoding];

    NSData*data = [NSDatadataWithBytes:cstr length:self.length];

    uint8_t digest[CC_SHA1_DIGEST_LENGTH];

    CC_SHA1(data.bytes, data.length, digest);

    NSMutableString*output = [NSMutableStringstringWithCapacity: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 = [NSMutableStringstringWithCapacity: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 = [selfcStringUsingEncoding:NSUTF8StringEncoding];

    NSData*data = [NSDatadataWithBytes:cstr length:self.length];

    uint8_t digest[CC_SHA1_DIGEST_LENGTH];

    CC_SHA1(data.bytes, data.length, digest);

    NSData* base64 = [[NSDataalloc]initWithBytes:digest length:CC_SHA1_DIGEST_LENGTH];

    base64 = [GTMBase64 encodeData:base64];

    NSString* output = [[NSStringalloc] 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 = [[NSDataalloc]initWithBytes:digest length:CC_MD5_DIGEST_LENGTH];

    base64 = [GTMBase64 encodeData:base64];

    NSString* output = [[NSStringalloc] initWithData:base64 encoding:NSUTF8StringEncoding];

    return output;

}

- (NSString*) base64

{   

    NSData* data = [self dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES];

    data = [GTMBase64 encodeData:data];

    NSString* output = [[NSStringalloc] initWithData:data encoding:NSUTF8StringEncoding];

    return output;

}

@end

實作時候不要忘記導入CC相關的庫的頭檔案

CommonCrypto/CommonDigest.h