ios - 在 iOS 中生成 SHA256

Question

我尝试使用 Arcane 在 iOS 中生成 SHA256具有以下数据的库:

字符串:Amount=50&BillerID=59&ChannelID=2&Context=34|check|test&ReturnURL=https://uat.myfatoora.com/ReceiptPOC.aspx&TxnRefNum=000000000020003&UserName=DCS
key :71DD0F73AFFBB47825FF9864DDE95F3B
结果是 409dc622b3bef5c9fc46e45c3210111fcb4536d3a55833316fe0dc8154b3ea34
我认为这是正确的。但是，Windows 对应方使用以下代码生成 SHA256:

Windows Phone Source Code:

public static string HmacSha256(string secretKey, string value)
    {
        var msg = CryptographicBuffer.ConvertStringToBinary(value, BinaryStringEncoding.Utf8);
        byte[] convertedHash = new byte[secretKey.Length / 2];

        for (int i = 0; i < secretKey.Length / 2; i++)
        {
            convertedHash[i] = (byte)Int32.Parse(secretKey.Substring(i * 2, 2), System.Globalization.NumberStyles.HexNumber);
        }

        // Create HMAC.
        var objMacProv = MacAlgorithmProvider.OpenAlgorithm(MacAlgorithmNames.HmacSha256);
        CryptographicHash hash = objMacProv.CreateHash(convertedHash.AsBuffer());

        hash.Append(msg);
        return CryptographicBuffer.EncodeToHexString(hash.GetValueAndReset());

    }

结果是: 94a20ca39c8487c7763823ec9c918d9e38ae83cb741439f6d129bcdef9edba73这与我得到的不同。有人可以帮我解决这个问题，让我知道上面的代码在做什么以及如何在 iOS 中复制它。

编辑:

 iOS Source code

 let key = self.md5(string: "71DD0F73AFFBB47825FF9864DDE95F3B")

    let hash = HMAC.SHA256(str, key: key)

Answer 1

这里的关键是您需要将您的 secret (一个十六进制字符串)转换为 NSData。换句话说，NSData字节流会“看起来”像 secret 。

这应该做你想要的:

    // Hex string to NSData conversion from here http://stackoverflow.com/questions/7317860/converting-hex-nsstring-to-nsdata
    NSString *secret = @"71DD0F73AFFBB47825FF9864DDE95F3B";
    NSData *dataIn = [@"Amount=50&BillerID=59&ChannelID=2&Context=34|check|test&ReturnURL=https://uat.myfatoora.com/ReceiptPOC.aspx&TxnRefNum=000000000020003&UserName=DCS" dataUsingEncoding:NSUTF8StringEncoding];
    NSMutableData *macOut = [NSMutableData dataWithLength:CC_SHA256_DIGEST_LENGTH];

    secret = [secret stringByReplacingOccurrencesOfString:@" " withString:@""];
    NSMutableData *secretData = [[NSMutableData alloc] init];
    unsigned char whole_byte;
    char byte_chars[3] = {'\0','\0','\0'};
    int i;
    for (i=0; i < [secret length]/2; i++) {
        byte_chars[0] = [secret characterAtIndex:i*2];
        byte_chars[1] = [secret characterAtIndex:i*2+1];
        whole_byte = strtol(byte_chars, NULL, 16);
        [secretData appendBytes:&whole_byte length:1];
    }

    CCHmac(kCCHmacAlgSHA256, secretData.bytes, secretData.length, dataIn.bytes, dataIn.length, macOut.mutableBytes);

    NSMutableString *stringOut = [NSMutableString stringWithCapacity:macOut.length];
    const unsigned char *macOutBytes = macOut.bytes;

    for (NSInteger i=0; i<macOut.length; ++i) {
        [stringOut appendFormat:@"%02x", macOutBytes[i]];
    }

    NSLog(@"dataIn: %@", dataIn);
    NSLog(@"macOut: %@", macOut);
    NSLog(@"stringOut: %@", stringOut);

输出:

2016-09-27 20:18:54.181 JKS[27562:5321334] dataIn: <416d6f75 6e743d35 30264269 6c6c6572 49443d35 39264368 616e6e65 6c49443d 3226436f 6e746578 743d3334 7c636865 636b7c74 65737426 52657475 726e5552 4c3d6874 7470733a 2f2f7561 742e6d79 6661746f 6f72612e 636f6d2f 52656365 69707450 4f432e61 73707826 54786e52 65664e75 6d3d3030 30303030 30303030 32303030 33265573 65724e61 6d653d44 4353>

2016-09-27 20:18:54.181 JKS[27562:5321334] macOut: <94a20ca3 9c8487c7 763823ec 9c918d9e 38ae83cb 741439f6 d129bcde f9edba73>

2016-09-27 20:18:54.181 JKS[27562:5321334] stringOut: 94a20ca39c8487c7763823ec9c918d9e38ae83cb741439f6d129bcdef9edba73

Updated with Swift (code should be cleaned up)

// http://stackoverflow.com/questions/29799361/generate-a-hmac-swift-sdk8-3-using-cchmac
func generateHMAC(key: String, data: String) -> String {
    let keyData = key.dataFromHexadecimalString()! as NSData
    let dataIn = data.data(using: .utf8)! as NSData
    var result: [CUnsignedChar]
    result = Array(repeating: 0, count: Int(CC_SHA256_DIGEST_LENGTH))
    CCHmac(CCHmacAlgorithm(kCCHmacAlgSHA256), keyData.bytes, keyData.length, dataIn.bytes, dataIn.length, &result)

    let hash = NSMutableString()
    for val in result {
        hash.appendFormat("%02hhx", val)
    }

    return hash as String
}

您可以使用此扩展将十六进制字符串转换为 Data

// Modified slightly http://stackoverflow.com/questions/26501276/converting-hex-string-to-nsdata-in-swift
extension String {

    func dataFromHexadecimalString() -> Data? {
        var data = Data(capacity: characters.count / 2)

        let regex = try! NSRegularExpression(pattern: "[0-9a-f]{1,2}", options: .caseInsensitive)
        regex.enumerateMatches(in: self, options: [], range: NSMakeRange(0, characters.count)) { match, flags, stop in
            let byteString = (self as NSString).substring(with: match!.range)
            var num = UInt8(byteString, radix: 16)
            data.append(&num!, count: 1)
        }

        return data
    }
}

并使用做类似的事情:

    let secret = "71DD0F73AFFBB47825FF9864DDE95F3B"
    let value = "Amount=50&BillerID=59&ChannelID=2&Context=34|check|test&ReturnURL=https://uat.myfatoora.com/ReceiptPOC.aspx&TxnRefNum=000000000020003&UserName=DCS"

    print("\(generateHMAC(key: secret, data: value))")

你的输出应该是 94a20ca39c8487c7763823ec9c918d9e38ae83cb741439f6d129bcdef9edba73

您将需要 #import <CommonCrypto/CommonCrypto.h>在您的桥接头中。