/**
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?javax.crypto.Mac;
import?javax.crypto.spec.SecretKeySpec;
import?java.math.BigInteger;

/**
?*?This?an?example?implementation?of?OCRA.?Visit?www.openauthentication.org?for
?*?more?information.
?*?
?*?@author?Johan?Rydell?PortWise
?*/
public?class?OCRA?{
	private?OCRA（）?{
	}

	/**
	?*?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_sha1（String?crypto?byte[]?keyBytes?byte[]?text）?{
		Mac?hmac?=?null;
		try?{
			hmac?=?Mac.getInstance（crypto）;
			SecretKeySpec?macKey?=?new?SecretKeySpec（keyBytes?“RAW“）;

			hmac.init（macKey）;
			return?hmac.doFinal（text）;
		}?catch?（Exception?e）?{
			e.printStackTrace（）;
		}
		return?null;
	}

	private?static?final?int[]?DIGITS_POWER
	//?0?1?2?3?4?5?6?7?8
	=?{?1?10?100?1000?10000?100000?1000000?10000000?100000000?};

	/**
	?*?This?method?converts?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];
		System.arraycopy（bArray?1?ret?0?ret.length）;
		return?ret;
	}

	/**
	?*?This?method?generates?an?OCRA?HOTP?value?for?the?given?set?of?parameters.
	?*?
	?*?@param?ocraSuite
	?*????????????the?OCRA?Suite
	?*?@param?key
	?*????????????the?shared?secret?HEX?encoded
	?*?@param?counter
	?*????????????the?counter?that?changes?on?a?per?use?basis?HEX?encoded
	?*?@param?question
	?*????????????the?challenge?question?HEX?encoded
	?*?@param?password
	?*????????????a?password?that?can?be?used?HEX?encoded
	?*?@param?sessionInformation
	?*????????????Static?information?that?identifies?the?current?session?Hex
	?*????????????encoded
	?*?@param?timeStamp
	?*????????????a?value?that?reflects?a?time
	?*?
	?*?@return?A?numeric?String?in?base?10?that?includes
	?*?????????{@link?truncationDigits}?digits
	?*/
	static?public?String?generateOCRA（String?ocraSuite?String?key
			String?counte

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2017-12-12?17:23??OTPProject\
?????文件?????????307??2011-12-16?11:39??OTPProject\.classpath
?????目錄???????????0??2017-12-12?17:23??__MACOSX\
?????目錄???????????0??2017-12-12?17:23??__MACOSX\OTPProject\
?????文件?????????212??2011-12-16?11:39??__MACOSX\OTPProject\._.classpath
?????文件?????????386??2011-12-06?18:26??OTPProject\.project
?????文件?????????212??2011-12-06?18:26??__MACOSX\OTPProject\._.project
?????目錄???????????0??2017-12-12?17:23??OTPProject\src\
?????文件????????8298??2011-12-07?09:21??OTPProject\src\OCRA.java
?????目錄???????????0??2017-12-12?17:23??__MACOSX\OTPProject\src\
?????文件?????????212??2011-12-07?09:21??__MACOSX\OTPProject\src\._OCRA.java
?????目錄???????????0??2017-12-12?17:23??OTPProject\src\org\
?????目錄???????????0??2017-12-12?17:23??OTPProject\src\org\openauthentication\
?????目錄???????????0??2017-12-12?17:23??OTPProject\src\org\openauthentication\otp\
?????文件????????6473??2011-12-06?18:32??OTPProject\src\org\openauthentication\otp\OneTimePasswordAlgorithm.java
?????目錄???????????0??2017-12-12?17:23??__MACOSX\OTPProject\src\org\
?????目錄???????????0??2017-12-12?17:23??__MACOSX\OTPProject\src\org\openauthentication\
?????目錄???????????0??2017-12-12?17:23??__MACOSX\OTPProject\src\org\openauthentication\otp\
?????文件?????????212??2011-12-06?18:32??__MACOSX\OTPProject\src\org\openauthentication\otp\._OneTimePasswordAlgorithm.java
?????文件????????1083??2011-12-07?09:21??OTPProject\src\org\openauthentication\otp\OTPTest.java
?????文件?????????212??2011-12-07?09:21??__MACOSX\OTPProject\src\org\openauthentication\otp\._OTPTest.java
?????文件?????????176??2017-12-12?17:23??__MACOSX\OTPProject\src\org\openauthentication\._otp
?????文件?????????176??2017-12-12?17:23??__MACOSX\OTPProject\src\org\._openauthentication
?????文件?????????176??2017-12-12?17:23??__MACOSX\OTPProject\src\._org
?????文件???????10931??2011-12-07?09:30??OTPProject\src\TestOCRA.java
?????文件?????????212??2011-12-07?09:30??__MACOSX\OTPProject\src\._TestOCRA.java
?????文件????????7675??2011-12-07?09:15??OTPProject\src\TOTP.java
?????文件?????????212??2011-12-07?09:15??__MACOSX\OTPProject\src\._TOTP.java
?????文件?????????176??2017-12-12?17:23??__MACOSX\OTPProject\._src
?????文件?????????176??2017-12-12?17:23??__MACOSX\._OTPProject