HASH FUNCTION IN JAVA
i need help!!
i have to create a program in java in which i want to compare passwords by using hash function.More specifically,the parameters of hash should be like this hash(password,salt).
which is the library that i have to use and how can i call it in main function?
thank you!
plz respond as soon as possible!
The same way you would call it in any other method :) You should start with the JCE develop guide and go from there. The more reading you can do on cryptography the better. If you understand the concepts, the Java code will become easier to write.
http://download.oracle.com/javase/6/docs/technotes/guides/security/crypto/CryptoSpec.html#MDEx
Similar Messages
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How to encrypt password with hash function in Java?
Hello, everybody!
I will need to store user passwords in a database, but for stronger security I want to store these passwords hashed, so I know I will need a column for the password and for the salt value.
So, I'd like that you indicate me a very good article or tutorial (preferable from Sun) that shows me how to use Java to encrypt and decrypt passwords with hash. It doesn't necessarily need to deal with database. I can implement this part myself after seeing how Java manage encryption with hash functions.
Thank you very much.
MarcosI will tell you more precisely what I want to get better for you to help me.
As I said I implemented in .NET what I need to implement in Java now. In my
database I have a table with this structure (I omitted that columns that are not
necessary to our discussion):
CREATE TABLE EMPLOYEES
ID NOT NULL PRIMARY KEY,
PASSWORD VARCHAR(40), -- password encrypted
HASH_SALT VARCHAR(10) -- salt value used to encrypt password
So, in the table I have a column to store the password encrypted and a column to
store the salt value.
Below is a little utility class (in C#) that I use to generate the salt and
the hashed password.
public static class PasswordUtilities
public static string GenerateSalt()
RNGCryptoServiceProvider encoder = new RNGCryptoServiceProvider();
byte[] buffer = new byte[5];
encoder.GetBytes(buffer);
return Convert.ToBase64String(buffer);
public static string EncryptPassword(string password, string salt)
string encryptedPassword =
FormsAuthentication.HashPasswordForStoringInConfigFile(
password + salt, "SHA1");
return encryptedPassword;
}As you can see, the class is fairly simple. It only has two methods: one to
generate the salt value that will be used to encrypt the password and another
one to encrypt the password. The method HashPasswordForStoringInConfigFile of
the FormsAuthentication class is what really hash the password with the salt
value. This class belongs to the .NET library, so we can't see its source code,
but it doesn't matter for our discussion as I know that we can implement
something similar in Java.
Below is a little sample code showing the use of the utility class above to
encrypt a password.
public class Encrypt
public static void Main(string args[])
string password = "Secret";
string salt = PasswordUtilities.GenerateSalt();
string encryptedPassword = PasswordUtilities.EncryptPassword(password, salt);
// now I store 'encryptedPassword' in the PASSWORD column and 'salt'
// in the HASH_SALT column in the EMPLOYEES table.
}To verify if a password is correct I can use the code below:
public class VerifyPassword
public static void Main(string args[])
string password = GetPasswordFromUser();
// Let's assume that employee is an instance that corresponds to a row
// in the database and the properties HashSalt and Password correspond
// to the HASH_SALT and PASSWORD columns respectively.
Employee employee = GetEmployeeFromDatabase(1);
string salt = employee.HashSalt;
string encryptedPassword = PasswordUtilities.EncryptPassword(password, salt);
bool passwordMatch = employee.Password.Equals(encryptedPassword);
System.Console.WriteLine(passwordMatch);
}The only thing that interest me in this discussion is the PasswordUtilities class.
As you saw its code is in C#, using the .NET framework libraries.
What I want is to have this same little class coded in Java, to generate the salt
value and to encrypt the password passed in using salt value generated. If you could
help me to do that with articles that have what I want or with code that already do
that I would really appreciate.
Thank you in advance.
Marcos -
Simply i want to save a password entered to a java program and save it in a MySQL database
Here I want to encrypt that password and save it in the database.... I prefer one way hash function encryption because it fulfills my need.
SHA-1 is the best in java now as I read from a article, is it?
What I need is that if someone can post a complete code which uses SHA-1 (if it is the best preferred one).
I've tried some codes published in the web but didn't work
one code worked very well but when I entered characters like "@#$%%" it failed.
Thank You!!!797241 wrote:
I've search using your key terms and got a good code that works ("java sha-1 example")
thanks for that
I didn't got that when i was searchingHard to believe.
So suggesting that working link was enough though you've put some other annoying comment tooIt is considered extremely bad mannered just to ask for code. If you have presented code that has problems and ask for help in fixing the problems you will normally get help but just to ask for code implies you are very lazy.
thanks for that too
I would rather prefer if you would have written "You are not going to get an answer, get the hell out of here!!!"Now that would have invoked the wrath of the moderators!
P.S. Just using a SHA-1 digest is insecure as the result is open to a dictionary attack. You should use a randomly seeded digest with both the random value and digest value being stored in the database. -
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Hi, I need to know the algorithm of the Hash Function that is used by Java in its HashMap, Properties, etc... classes.
Can I get it somewhere or is it private? I need it for documentation purposes.
Thanks!
SigurdHi.
You can download the source for the entire JDK from the usual download locations, so you can see the details of the implementation there. If you're looking for a higher level description, I don't know where you'd find that, other than a few pages which document general ways to get well distributed hashes; look at http://java.sun.com/developer/Books/effectivejava/Chapter3.pdf for an example of this - a chapter from the mighty Joshua Bloch's 'Effective Java'.
Regards,
Lance -
Hash function not use MessageDigest
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implements Cloneable {
public SHA();
public int engineGetLength(); // returns 20
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public void engineUpdate(byte[] buffer, int offset, int length);
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public void engineReset();
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To use it:
import java.security.*;
SHA state = new SHA(); // pass argument (0) if you want the deprecated SHA-0 algorithm instead of SHA-1
byte b = ...;
state.engineUpdate(b);
byte[] buffer = ...;
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public String validation(String a, Container container) {
//write your code here
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Check these things :
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10.10.0.55
sapmnt
trans
edixiin
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I am new to XI. I was working on Message mapping in intergration repository.
To map the source messages to target messages, we do graphical kind of mapping like drag and drop.
There are some functions aavilable at the bottom like concatehate, trim and etc. which we use if we need to modify the source message and map to target.
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To get more understanding on mapping go thro this link(PDF File)
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regards,
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Message was edited by: Venkataramanan -
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hello
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Now we need replicate the same in CRM. For this we need to create KB, Version & write a variant function in Java class in SCE. In that variant function we need to call a function module and get the customer master / Business partner value as similar to ECC process described above.
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Is there any object(like context etc.) that IPC server-side and Webapps share?
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How to access C/C++ functions in Java using existing .dll library
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I am having well written API in C/C++.This C/C++ files are made into *.dll files.The api are working fine.
I wan't access the C/C++ api functions in Java., just using System.LoadLibrary("*.dll").Is it possible.I kindly request you to suggest some examples and how to do this.
Its Urgent !.
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V K LALIn general you cannot simply access dlls that have already been written. The DLLs called using JNI must conform to JNI calling standards.
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Hi there,
What I want to do is: calling a stored procedure OR function from Java with a String-variable as input and receiving a geometry (SDO_GEOMETRY).
I’m facing currently the problem of calling a stored function on oracle 11g from Java using JPA (EclipseLink), Spring 2.5.6 returning an MDSYS.SDO_GEOMETRY object.
I’ve tried to call a stored procedure with MDSYS.SDO_GEOMETRY as an output parameter instead, but with no success.
The function’s signature looks like this:
CREATE or REPLACE
FUNCTION GET_GEO_BRD_FUNCTION(p_geo_brd_id IN VARCHAR2) RETURN MDSYS.SDO_GEOMETRY AS
sdo_geom MDSYS.SDO_GEOMETRY := null;
BEGIN
/* do some fancy stuff on the database side */
SELECT sp_geom
INTO sdo_geom
FROM geo_brd WHERE id = p_geo_brd_id;
RETURN sdo_geom;
END;
The calling code looks like this:
MyClass extends JpaDaoSupport{
/** logger */
protected static final ILogger LOG = LogFactory.getLogger(MyClass.class);
* {@inheritDoc}
* @see com.example.MyClass#calculateGeometry(java.lang.String)
@Override
public JGeometry calculateGeometry(final String id) {
JGeometry geometry = null;
final JpaCallback action = new JpaCallback() {
@Override
public Object doInJpa(final EntityManager em) throws PersistenceException {
final Session session = JpaHelper.getEntityManager(em).getActiveSession();
final StoredFunctionCall functionCall = new StoredFunctionCall();
functionCall.setProcedureName("GET_GEO_BRD_FUNCTION");
functionCall.addNamedArgument("p_geo_brd_id");
functionCall.setResult("sdo_geom", Oracle.sql.STRUCT.class);
final ValueReadQuery query = new ValueReadQuery();
query.setCall(functionCall);
query.addArgument("p_geo_brd_id");
final ArrayList args = new ArrayList();
args.add("2e531e62-2105-4522-978a-ab8baf19e273");// hardcoded for test
final Object result = session.executeQuery(query, args);
return result;
final STRUCT result = (STRUCT) this.getJpaTemplate().execute(action);
try {
geometry = JGeometry.load(result);
} catch (final SQLException e) {
MyClass.LOG.error("Error loading JGeometry from STRUCT.", e);
return null;
return geometry;
And when I execute the query I get the following error:
Internal Exception: java.sql.SQLException: ORA-06550: Row 1, Column 13:
PLS-00382: expression is of wrong type
ORA-06550: Row 1, Column 7:
PL/SQL: Statement ignored
Error Code: 6550
Call: BEGIN ? := GET_GEO_BRD_FUNCTION(p_geo_brd_id=>?); END;
bind => [=> sdo_geom, 2e531e62-2105-4522-978a-ab8baf19e273]
Query: ValueReadQuery()
So I thought may be let's try it with a stored procedure instead...
The procedure looks like this:
CREATE or REPLACE
PROCEDURE GET_GEO_BRD_PROCEDURE(p_geo_brd_id IN VARCHAR2, sdo_geom OUT MDSYS.SDO_GEOMETRY) AS
BEGIN
/* do some fancy stuff on the database side */
SELECT sp_geom
INTO sdo_geom
from geo_brd where id = p_geo_brd_id;
END;
The calling Java code in case of the stored procedure looks like this (only the content of the JPACallback has changed):
@Override
public Object doInJpa(final EntityManager em) throws PersistenceException {
final Session session = JpaHelper.getEntityManager(em).getActiveSession();
final StoredProcedureCall spCall = new StoredProcedureCall();
spCall.setProcedureName("GET_GEO_BRD_PROCEDURE");
spCall.addNamedArgument("p_geo_brd_id", "p_geo_brd_id", String.class);
spCall.addNamedOutputArgument("sdo_geom", "sdo_geom", OracleTypes.STRUCT);
final ValueReadQuery query = new ValueReadQuery();
query.setCall(spCall);
query.addArgument("p_geo_brd_id"); // input
final List args = new ArrayList();
args.add("2e531e62-2105-4522-978a-ab8baf19e273");// hardcoded for test
final Object result = session.executeQuery(query, args);
return result;
And when I execute the query I get the following error:
java.sql.SQLException: ORA-06550: Row 1, Column 13:
PLS-00306: wrong number or types of arguments in call to 'GET_GEO_BRD_PROCEDURE'
ORA-06550: Row 1, Column 7:
PL/SQL: Statement ignored
So both exceptions look quite similar.
I guess in both cases the exception description leads to the assumption, that the wrong type for the return value / output parameter is used…
So - how can a receive a MDSYS_SDO_GEOMETRY object from a stored procedure or stored function in Java ?
What is wrong in the Java code?
Thank you in advance for any suggestions!
Yours,
Chris
Edited by: user3938161 on 20.12.2011 07:46
Edited by: user3938161 on Dec 20, 2011 8:06 AM: added variable declaration of JGeometry geometry in source codeThanks, that did the trick! ;-)
Here is now the code for stored procedure and function for anybody else encountering the same troubles... (be aware of the parameter order and/or naming!)
Code for stored functions:
final JpaCallback action = new JpaCallback() {
@Override
public Object doInJpa(final EntityManager em) throws PersistenceException {
final Session session = JpaHelper.getEntityManager(em).getActiveSession();
* Using CallableStatement for stored functions
STRUCT st = null;
CallableStatement cs = null;
final DatabaseLogin login = session.getLogin();
final Connection _conn = (Connection) login.connectToDatasource(session.getDatasourceLogin().buildAccessor(), session);
try {
try {
cs = _conn.prepareCall("{? = call GET_GEO_BRD_FUNCTION(?)}");
cs.registerOutParameter(1, OracleTypes.STRUCT, "MDSYS.SDO_GEOMETRY");
cs.setString(2, "2e531e62-2105-4522-978a-ab8baf19e273");//TODO: hardcoded for test
cs.execute();
} catch (final SQLException e) {
MyClass.LOG.error("An exception occured calling the stored procedure", e);
if (cs != null) {
//reading geometry from the database
try {
st = (STRUCT) cs.getObject(1);
} catch (final SQLException e) {
MyClass.LOG.error("An exception occured converting the query result to oracle.sql.STRUCT", e);
} finally {
try {
if (_conn != null && !_conn.isClosed()) {
_conn.close();
} catch (final SQLException e) {
MyClass.LOG.error("An exception occured on closing the database connection.", e);
return st;
final STRUCT result = (STRUCT) this.getJpaTemplate().execute(action);
The code for stored procedure solution:
final JpaCallback action = new JpaCallback() {
@Override
public Object doInJpa(final EntityManager em) throws PersistenceException {
final Session session = JpaHelper.getEntityManager(em).getActiveSession();
* Using CallableStatement for stored procedure
STRUCT st = null;
CallableStatement cs = null;
final DatabaseLogin login = session.getLogin();
final Connection _conn = (Connection) login.connectToDatasource(session.getDatasourceLogin().buildAccessor(), session);
try {
try {
cs = _conn.prepareCall("{call GET_GEO_BRD_PROCEDURE(?,?)}");
cs.setString("p_geo_brd_id", "2e531e62-2105-4522-978a-ab8baf19e273");
cs.registerOutParameter("sdo_geom", OracleTypes.STRUCT, "MDSYS.SDO_GEOMETRY");
cs.execute();
} catch (final SQLException e) {
MyClass.LOG.error("An exception occured calling the stored procedure", e);
if (cs != null) {
//reading geometry from the database
try {
st = (STRUCT) cs.getObject("sdo_geom");
} catch (final SQLException e) {
MyClass.LOG.error("An exception occured converting the query result to oracle.sql.STRUCT", e);
} finally {
try {
if (_conn != null && !_conn.isClosed()) {
_conn.close();
} catch (final SQLException e) {
MyClass.LOG.error("An exception occured on closing the database connection.", e);
return st;
final STRUCT result = (STRUCT) this.getJpaTemplate().execute(action); -
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Sir/Madem
I'm new in java. I have just started learning java.
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Sir/Madem
I'm new in java. I have just started learning java.
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Hi!
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