java版的SHA-1

http://www.diybl.com/　2007-2-6 　网络　点击: 　[ 评论 ]

/**
* This Java Class consists the server side for the wondeful JavaScript library 'sha1.js'. I wrote it because I basically needed
* some cheap client/server login authentication by the usual key/data system. Besides, I got the creeps watching the password
* posted unencrypted via http requests. This class makes sure that if your client is using the 'sha1.js' to encrypt the password
* with a key sent by the server, you can always repeat the encrypting on the server side (using the same key) and compare the
* encrypted strings. Since anyone who is trapping the http requests can actually send you the same encrypted string, I suggest
* you use the client's IP address as the base for the key generation. Since IP address spoofing is not a problem, this authentication
* method is not a very secured solution. If you need a full proof solution use ssl. However, this one, sure beats nothing.
* Feel free to do with it whatever you want
* This Class is an Abstract Class, to make sure you do not create any new instances of it. It does not throw any exceptions and
* the code is much more 'C' like than pure object oriented. There are no implemented interfaces and no inheritance in use. In fact, it
* is written as close as possible to the original JavaScript code. I did not test tweaking the instance variables but if you do change
* them, make sure to apply the same change in the 'sha1.js' library or you won't get the same encrypted strings.
* You can call each one of the 6 work methods by using something like: SHA1.hex_hmac_sha1("key", "data");
* They are the only public methods. All are public and static. You have no reason to call the private ones anyway.
* The 'sha1.js' is a JavaScript implementation of the Secure Hash Algorithm, SHA-1, as defined in FIPS PUB 180-1.
* JavaScript Version 2.1 Copyright Paul Johnston 2000 - 2002. Other contributors to JavaScript version: Greg Holt,
* Andrew Kepert, Ydnar, Lostinet Distributed under the BSD License
* See <a href="http://pajhome.org.uk/crypt/md5">http://pajhome.org.uk/crypt/md5</a> for details.
* Author: T.N.Silverman (C.T.Xm - SiA Riga, LV) <a href="mailto:tnsilver@ctcm.com">mailto:tnsilver@ctxm.com</a>
* Creation date: (3/27/2004 5:57:00 PM)
* Don't forget to visit my company, CTXM site at <a href="http://www.ctxm.com">http://www.ctxm.com</a> where you will find reference to all of the games this code is used in.
*/
public abstract class SHA1 {
private static final boolean hexcase = false;/* hex output format. false - lowercase; true - uppercase */
private static final String b64pad = "="; /* base-64 pad character. "=" for strict RFC compliance */
private static final int chrsz = 8; /* bits per input character. 8 - ASCII; 16 - Unicode */
/**
* This is one of the functions you'll usually want to call
* It take a string arguments and returns either hex or base-64 encoded strings
* Creation date: (3/27/2004 6:05:10 PM)
* @author T.N.Silverman
* @version 1.0.0
* @return java.lang.String
* @param key java.lang.String
* @param data java.lang.String
*/
public static String b64_hmac_sha1(String key, String data) {
return binb2b64(core_hmac_sha1(key, data));
}
/**
* This is one of the functions you'll usually want to call
* It take a string argument and returns either hex or base-64 encoded strings
* Creation date: (3/27/2004 6:05:10 PM)
* @author T.N.Silverman
* @version 1.0.0
* @return java.lang.String
* @param s java.lang.String
*/
public static String b64_sha1(String s) {
s = (s==null) ? "" : s;
return binb2b64(core_sha1(str2binb(s), s.length() * chrsz));
}
/**
* Convert an array of big-endian words to a base-64 string
* Creation date: (3/27/2004 6:05:10 PM)
* @author T.N.Silverman
* @version 1.0.0
* @return java.lang.String
* @param binarray int[]
*/
private static String binb2b64(int[] binarray) {
String tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
String str = "";
binarray = strechBinArray(binarray, binarray.length * 4);
for (int i = 0; i < binarray.length * 4; i += 3) {
int triplet =
(((binarray[i >> 2] >> 8 * (3 - i % 4)) & 0xFF) << 16)
| (((binarray[i + 1 >> 2] >> 8 * (3 - (i + 1) % 4)) & 0xFF) << 8)
| ((binarray[i + 2 >> 2] >> 8 * (3 - (i + 2) % 4)) & 0xFF);
for (int j = 0; j < 4; j++) {
if (i * 8 + j * 6 > binarray.length * 32)
str += b64pad;
else
str += tab.charAt((triplet >> 6 * (3 - j)) & 0x3F);
}
}
return cleanB64Str(str);
}
/**
* Convert an array of big-endian words to a hex string.
* Creation date: (3/27/2004 6:05:10 PM)
* @author T.N.Silverman
* @version 1.0.0
* @return java.lang.String
* @param binarray int[]
*/
private static String binb2hex(int[] binarray) {
String hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";
String str = "";
for (int i = 0; i < binarray.length * 4; i++) {
char a = (char) hex_tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8 + 4)) & 0xF);
char b = (char) hex_tab.charAt((binarray[i >> 2] >> ((3 - i % 4) * 8))