MD5/SHA1/Hmac_SHA1

#import <CommonCrypto/CommonDigest.h>

+ (NSString *) md5:(NSString *) input {
    const char *cStr = [input UTF8String];
    unsigned char digest[CC_MD5_DIGEST_LENGTH];
    CC_MD5( cStr, (unsigned int)strlen(cStr), digest ); // This is the md5 call
    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:(NSString *)input{
     NSData *data = [input dataUsingEncoding:NSUTF8StringEncoding];

    uint8_t digest[CC_SHA1_DIGEST_LENGTH];

    CC_SHA1(data.bytes, (unsigned int)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;
}

//额外添加了base64转码
+(NSString *)Base_HmacSha1:(NSString *)key data:(NSString *)data{
　　const char *cKey = [key cStringUsingEncoding:NSASCIIStringEncoding];
　　const char *cData = [data cStringUsingEncoding:NSASCIIStringEncoding];
　　//Sha256:
　　// unsigned char cHMAC[CC_SHA256_DIGEST_LENGTH];
　　//CCHmac(kCCHmacAlgSHA256, cKey, strlen(cKey), cData, strlen(cData), cHMAC);

　　//sha1
　　unsigned char cHMAC[CC_SHA1_DIGEST_LENGTH];
　　CCHmac(kCCHmacAlgSHA1, cKey, strlen(cKey), cData, strlen(cData), cHMAC);

　　NSData *HMAC = [[NSData alloc] initWithBytes:cHMAC length:sizeof(cHMAC)];

　　//将加密结果进行一次BASE64编码。
　　NSString *hash = [HMAC base64EncodedStringWithOptions:0];
　　return hash;
}