此问题与RFC6238中指定的TOTP有关：https://tools.ietf.org/html/rfc6238#section-1.2。
我将实施RFC6238以生成 10位 TOTP密码，稍后将在POST请求中使用该密码。 TOTP的样本输入和输出应该是这样的：
示例输入：
共享密钥：“ninja@example.comHDECHALLENGE003”（不带双引号）
使用的哈希函数：HMAC-SHA-512
T0 = 0，Timestep = 30秒（根据RFC6238中的规定）
预计10位数的TOTP
示例输出：
TOTP成功生成：1773133250，时间为星期一，2014年3月17日15:20:51 GMT
base64编码的POST授权用户名/密码请求：bmluamFAZXhhbXBsZS5jb206MTc3MzEzMzI1MA ==
（我已将示例POST授权解码为'ninja@example.com:1773133250'因此我可以说示例TOTP输出为1773133250）
根据rfc6238规范尝试制作自己的脚本后，我无法获得与上述示例输入相同的输出。我尝试使用在线提供的其他可用在线TOTP模块（主要是在Python中），以发现它们生成的输出与我创建的脚本相同。最后，我尝试了RFC6238示例中给出的Java代码，并得出了与我的脚本相同的结果，即：
尝试输入：
六角编码为HMAC512种子： “6E696E6A61406578616D706C652E636F6D4844454348414C4C454E4745303033” + “6E696E6A61406578616D706C652E636F6D4844454348414C4C454E4745303033”;
输入的时间是1395069651L，表示样本输出中收到的时间
尝试的结果（自定义脚本，其他Python模块的相同输出以及RFC6238文档中给出的Java实现）：
生成TOTP：0490867067
这是我第一次尝试在Python中生成TOTP时使用的代码：
# Mission/Task Description:
# * For the "password", provide an 10-digit time-based one time password conforming to RFC6238 TOTP.
#
# ** You have to read RFC6238 (and the errata too!) and get a correct one time password by yourself.
# ** TOTP's "Time Step X" is 30 seconds. "T0" is 0.
# ** Use HMAC-SHA-512 for the hash function, instead of the default HMAC-SHA-1.
# ** Token shared secret is the userid followed by ASCII string value "HDECHALLENGE003" (not including double quotations).
#
# *** For example, if the userid is "ninja@example.com", the token shared secret is "ninja@example.comHDECHALLENGE003".
# *** For example, if the userid is "ninjasamuraisumotorishogun@example.com", the token shared secret is "ninjasamuraisumotorishogun@example.comHDECHALLENGE003"
#
import hmac
import hashlib
import time
import sys
import struct
userid = "ninja@example.com"
secret_suffix = "HDECHALLENGE003"
shared_secret = userid+secret_suffix
timestep = 30
T0 = 0
def HOTP(K, C, digits=10):
"""HTOP:
K is the shared key
C is the counter value
digits control the response length
"""
K_bytes = K.encode()
C_bytes = struct.pack(">Q", C)
hmac_sha512 = hmac.new(key = K_bytes, msg=C_bytes, digestmod=hashlib.sha512).hexdigest()
return Truncate(hmac_sha512)[-digits:]
def Truncate(hmac_sha512):
"""truncate sha512 value"""
offset = int(hmac_sha512[-1], 16)
binary = int(hmac_sha512[(offset *2):((offset*2)+8)], 16) & 0x7FFFFFFF
return str(binary)
def TOTP(K, digits=10, timeref = 0, timestep = 30):
"""TOTP, time-based variant of HOTP
digits control the response length
the C in HOTP is replaced by ( (currentTime - timeref) / timestep )
"""
C = int ( 1395069651 - timeref ) // timestep
return HOTP(K, C, digits = digits)
passwd = TOTP("ninja@example.comHDECHALLENGE003ninja@example.comHDECHALLENGE003", 10, T0, timestep).zfill(10)
print passwd
这是Java中的第二个代码，它本质上是RFC6238中的Java实现的修改版本：
/**
Copyright (c) 2011 IETF Trust and the persons identified as
authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, is permitted pursuant to, and subject to the license
terms contained in, the Simplified BSD License set forth in Section
4.c of the IETF Trust's Legal Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info).
*/
import java.lang.reflect.UndeclaredThrowableException;
import java.security.GeneralSecurityException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.math.BigInteger;
import java.util.TimeZone;
import java.util.Calendar;
/**
* This is an example implementation of the OATH
* TOTP algorithm.
* Visit www.openauthentication.org for more information.
*
* @author Johan Rydell, PortWise, Inc.
*/
public class TOTP {
private TOTP() {}
/**
* This method uses the JCE to provide the crypto algorithm.
* HMAC computes a Hashed Message Authentication Code with the
* crypto hash algorithm as a parameter.
*
* @param crypto: the crypto algorithm (HmacSHA1, HmacSHA256,
* HmacSHA512)
* @param keyBytes: the bytes to use for the HMAC key
* @param text: the message or text to be authenticated
*/
private static byte[] hmac_sha(String crypto, byte[] keyBytes,
byte[] text){
try {
Mac hmac;
hmac = Mac.getInstance(crypto);
SecretKeySpec macKey =
new SecretKeySpec(keyBytes, "RAW");
hmac.init(macKey);
return hmac.doFinal(text);
} catch (GeneralSecurityException gse) {
throw new UndeclaredThrowableException(gse);
}
}
/**
* This method converts a HEX string to Byte[]
*
* @param hex: the HEX string
*
* @return: a byte array
*/
private static byte[] hexStr2Bytes(String hex){
// Adding one byte to get the right conversion
// Values starting with "0" can be converted
byte[] bArray = new BigInteger("10" + hex,16).toByteArray();
// Copy all the REAL bytes, not the "first"
byte[] ret = new byte[bArray.length - 1];
for (int i = 0; i < ret.length; i++)
ret[i] = bArray[i+1];
return ret;
}
private static final long[] DIGITS_POWER
// 0 1 2 3 4 5 6 7 8 9 10
= {1,10,100,1000,10000,100000,1000000,10000000,100000000,1000000000,10000000000L};
/**
* This method generates a TOTP value for the given
* set of parameters.
*
* @param key: the shared secret, HEX encoded
* @param time: a value that reflects a time
* @param returnDigits: number of digits to return
*
* @return: a numeric String in base 10 that includes
* {@link truncationDigits} digits
*/
public static String generateTOTP(String key,
String time,
String returnDigits){
return generateTOTP(key, time, returnDigits, "HmacSHA1");
}
/**
* This method generates a TOTP value for the given
* set of parameters.
*
* @param key: the shared secret, HEX encoded
* @param time: a value that reflects a time
* @param returnDigits: number of digits to return
*
* @return: a numeric String in base 10 that includes
* {@link truncationDigits} digits
*/
public static String generateTOTP256(String key,
String time,
String returnDigits){
return generateTOTP(key, time, returnDigits, "HmacSHA256");
}
/**
* This method generates a TOTP value for the given
* set of parameters.
*
* @param key: the shared secret, HEX encoded
* @param time: a value that reflects a time
* @param returnDigits: number of digits to return
*
* @return: a numeric String in base 10 that includes
* {@link truncationDigits} digits
*/
public static String generateTOTP512(String key,
String time,
String returnDigits){
return generateTOTP(key, time, returnDigits, "HmacSHA512");
}
/**
* This method generates a TOTP value for the given
* set of parameters.
*
* @param key: the shared secret, HEX encoded
* @param time: a value that reflects a time
* @param returnDigits: number of digits to return
* @param crypto: the crypto function to use
*
* @return: a numeric String in base 10 that includes
* {@link truncationDigits} digits
*/
public static String generateTOTP(String key,
String time,
String returnDigits,
String crypto){
int codeDigits = Integer.decode(returnDigits).intValue();
String result = null;
// Using the counter
// First 8 bytes are for the movingFactor
// Compliant with base RFC 4226 (HOTP)
while (time.length() < 16 )
time = "0" + time;
// Get the HEX in a Byte[]
byte[] msg = hexStr2Bytes(time);
byte[] k = hexStr2Bytes(key);
byte[] hash = hmac_sha(crypto, k, msg);
// put selected bytes into result int
int offset = hash[hash.length - 1] & 0xf;
int binary =
((hash[offset] & 0x7f) << 24) |
((hash[offset + 1] & 0xff) << 16) |
((hash[offset + 2] & 0xff) << 8) |
(hash[offset + 3] & 0xff);
long otp = binary % DIGITS_POWER[codeDigits];
result = Long.toString(otp);
while (result.length() < codeDigits) {
result = "0" + result;
}
return result;
}
public static void main(String[] args) {
// Seed for HMAC-SHA1 - 20 bytes
String seed = "3132333435363738393031323334353637383930";
// Seed for HMAC-SHA256 - 32 bytes
String seed32 = "3132333435363738393031323334353637383930" +
"313233343536373839303132";
// Seed for HMAC-SHA512 - 64 bytes
String seed64 = "6E696E6A61406578616D706C652E636F6D4844454348414C4C454E4745303033";
//NOTE: this is the 16-bit/hex encoded representation of "ninja@example.comHDECHALLENGE003"
String seednew = "6E696E6A61406578616D706C652E636F6D4844454348414C4C454E4745303033" +
"6E696E6A61406578616D706C652E636F6D4844454348414C4C454E4745303033";
long T0 = 0;
long X = 30;
long current = System.currentTimeMillis()/1000;
System.out.println(current);
long testTime[] = {59L, 1234567890L,1395069651L};
String steps = "0";
DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
df.setTimeZone(TimeZone.getTimeZone("UTC"));
try {
System.out.println(
"+---------------+-----------------------+" +
"------------------+--------+--------+");
System.out.println(
"| Time(sec) | Time (UTC format) " +
"| Value of T(Hex) | TOTP | Mode |");
System.out.println(
"+---------------+-----------------------+" +
"------------------+--------+--------+");
for (int i=0; i<testTime.length; i++) {
long T = (testTime[i] - T0)/X;
steps = Long.toHexString(T).toUpperCase();
while (steps.length() < 16) steps = "0" + steps;
String fmtTime = String.format("%1$-11s", testTime[i]);
String utcTime = df.format(new Date(testTime[i]*1000));
System.out.print("| " + fmtTime + " | " + utcTime +
" | " + steps + " |");
System.out.println(generateTOTP(seed, steps, "8",
"HmacSHA1") + "| SHA1 |");
System.out.print("| " + fmtTime + " | " + utcTime +
" | " + steps + " |");
System.out.println(generateTOTP(seed32, steps, "8",
"HmacSHA256") + "| SHA256 |");
System.out.print("| " + fmtTime + " | " + utcTime +
" | " + steps + " |");
System.out.println(generateTOTP(seed64, steps, "10",
"HmacSHA256") + "| SHA256 |");
System.out.print("| " + fmtTime + " | " + utcTime +
" | " + steps + " |");
System.out.println(generateTOTP(seednew, steps, "10",
"HmacSHA512") + "| SHA512 |");
System.out.println(
"+---------------+-----------------------+" +
"------------------+--------+--------+");
}
}catch (final Exception e){
System.out.println("Error : " + e);
}
}
}
请注意，对于修改后的RFC Java代码，输出将是testTime []数组中列出的几个日期/时间的输出，但是任务的示例输入中的目标GMT也包含在此处。在我的Ubuntu中进行的测试显示了与我的Python脚本相同的结果。
我相信我已遵循任务给出的指示。我使用实际的RFC给定Java代码来发现它没有生成与任务中给出的输出相同的输出。我联系了该任务的提供者，询问是否存在错误，但他们说这是正确的。
也许我在这里遗漏了一些东西，例如任务提供者实际加密共享密钥的方式？
答案 0 :(得分：0)
您确定TOTP 1773133250是正确的吗？由于您的机密只有32个字节，因此您是否确定返回1773133250的提供程序正在构建与您相同的64字节机密？
在您的代码中，您将32字节的机密并串联在一起以获得64字节。
我正在使用FusionAuth-2FA Java库，如果将32个字节的密码连接在一起以获得一个64字节的密码，则会得到与您相同的结果。
我已经阅读了RFC，但对于我来说，尚不清楚实现者是否需要将机密扩展到特定字节大小。
可能是您的代码正确，而1773133250是一个令人不快的听证会。
这是我的测试代码：
@Test
public void stackOverflow_42546493() {
// Mon, 17 Mar 2014 15:20:51 GMT
ZonedDateTime date = ZonedDateTime.of(2014, 3, 17, 15, 20, 51, 0, ZoneId.of("GMT"));
long seconds = date.toEpochSecond();
assert seconds == 1395069651L;
long timeStep = seconds / 30;
// Your shared key in a 32 byte string
String rawSecret = "ninja@example.comHDECHALLENGE003";
String rawSecret64 = rawSecret + rawSecret; // 64 bytes
// Using 32 byte secret
String code = TwoFactor.calculateVerificationCode(rawSecret, timeStep, Algorithm.HmacSHA512, 10);
assert code.equals("1264436375");
// Using 64 byte secret
String code = TwoFactor.calculateVerificationCode(rawSecret64, timeStep, Algorithm.HmacSHA512, 10);
assert code.equals("0490867067");
}